JP2015185772A - Back sheet for solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a back sheet for a solar cell module, which is excellent in adhesion to a filler used for a solar cell and in weather resistance, maintains electric output characteristic, and has a satisfactory appearance, not only in an environment where it is actually used as a solar cell but also in a case of an enhancement test in a high temperature high humidity atmosphere conducted to evaluate the solar cell module.SOLUTION: In a back sheet for a solar cell module in which an adhesive layer is formed, the adhesive layer is formed from an adhesive for a back sheet, containing polymer containing an unsaturated double bond having at the terminal of a side chain an ethylenic unsaturated double bond and having a molecular weight distribution (weight average molecular weight/number average molecular weight) of 1.5 to 6.0.

Description

  The present invention relates to a back sheet for a solar cell module. More specifically, the present invention relates to a solar cell module backsheet, a solar cell module having a solar cell module backsheet, and a solar cell having the solar cell module.

  Since the solar cell module is mainly used outdoors, its material and structure are required to have durability and weather resistance. In particular, the solar cell module backsheet is required to have a weather resistance and a low water vapor transmission rate, that is, excellent moisture barrier properties. Furthermore, since it is necessary to maintain the performance of a solar cell for about 20 years, in order to evaluate the durability of the solar cell, for example, an accelerated test in a high-temperature and high-humidity atmosphere at 85 ° C. and a relative humidity of 85% Has been done.

  Conventionally, an ethylene-vinyl acetate copolymer (hereinafter referred to as EVA) has been used as a filler for a solar cell module backsheet because it has weather resistance and flame retardancy (for example, Patent Document 1 and 2). Moreover, since it is excellent in electrical insulation as a back seat | sheet for solar cell modules, polyester films, such as a polyethylene terephthalate, are used (for example, refer patent documents 3-6). However, the polyester film used in the solar cell module backsheet and EVA used as a filler are excellent in adhesiveness during the production of solar cells, but the adhesiveness decreases with time. There are drawbacks.

  Moreover, the stain | pollution | contamination by the coloring resin layer currently formed in the sheet | seat for back surface protection for solar cells adhering to the fluororesin sheet | seat used when laminating a solar cell module does not stand out on the surface of a fluororesin sheet For this reason, a solar cell back surface protection sheet having a multilayer colored layer in which a transparent layer and a colored layer are laminated from the side that adheres to the sealing material has been proposed (see, for example, Patent Document 7). However, this solar cell back surface protection sheet originally requires a transparent layer that may not be used, and the transparent layer remains attached to the fluororesin sheet.

  Therefore, in recent years, it is used not only in an environment actually used as a solar cell but also in a solar cell even when an accelerated test is performed in a high-temperature and high-humidity atmosphere studied when evaluating a solar cell module. Development of a back sheet for a solar cell module that is excellent in adhesiveness and weather resistance to a filler, maintains electric output characteristics, and has a good appearance is desired.

Japanese National Patent Publication No. 08-500214 Japanese translation of PCT publication No. 2002-520820 JP 2001-1111073 A Japanese Patent Laid-Open No. 2002-100788 JP 2002-134771 A JP 2002-026354 A JP 2011-222947 A

  The present invention has been made in view of the above prior art, and performs not only an environment actually used as a solar cell but also an accelerated test in a high-temperature and high-humidity atmosphere considered when evaluating a solar cell module. Even if it is a case, it aims at providing the solar cell module backsheet which is excellent in the adhesiveness and weather resistance with respect to the filler used for a solar cell, maintaining an electrical output characteristic, and having a favorable external appearance. .

  The present invention is not limited to the environment actually used as a solar cell, but also to a solar cell even when an accelerated test is performed in a high-temperature and high-humidity atmosphere studied when evaluating a solar cell module. An object of the present invention is to provide a solar cell module having a back sheet for a solar cell module that has excellent adhesion and weather resistance to the used filler, maintains electric output characteristics, and has a good appearance.

  The present invention is used not only in an environment actually used as a solar cell, but also in a solar cell, even when an accelerated test is performed in a high-temperature and high-humidity atmosphere studied when evaluating a solar cell module. An object of the present invention is to provide a solar cell having a back sheet for a solar cell module that is excellent in adhesiveness and weather resistance with respect to the filler, maintains electric output characteristics, and has a good appearance.

The present invention
(1) A solar cell module backsheet formed with an adhesive layer, wherein the adhesive layer has an ethylenically unsaturated double bond at the end of a side chain, and has a molecular weight distribution (weight average molecular weight / A backsheet for a solar cell module, characterized in that it is formed of an adhesive for backsheet containing an unsaturated double bond-containing polymer having a number average molecular weight) of 1.5 to 6.0,
(2) The unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain is at least one selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer Unsaturated double bond-containing polymer, carboxyl group and / or polymer obtained by reacting a polymer obtained by polymerizing a monomer component containing the monomer and a monomer having a carboxyl group and / or a hydroxyl group A polymer obtained by polymerizing a monomer component containing a monomer having a hydroxyl group and at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer; An unsaturated double bond-containing polymer obtained by reaction, a polymer obtained by polymerizing a monomer component containing a monomer having a carboxyl group and / or a hydroxyl group, and an isocyanate group-containing monomer are reacted. An unsaturated double bond-containing polymer, a polymer obtained by polymerizing a monomer component containing an isocyanate group-containing monomer, and a monomer having a carboxyl group and / or a hydroxyl group. Unsaturated double bond-containing polymer, unsaturated double bond-containing polymer obtained by polymerizing a monomer component containing (meth) acrylic acid (vinyloxyalkoxy) alkyl, and a monomer having an acid anhydride group At least one selected from the group consisting of a polymer obtained by polymerizing a monomer component containing a polymer and an unsaturated double bond-containing polymer obtained by reacting a monomer having a hydroxyl group. The back sheet for a solar cell module according to (1), which is a kind of unsaturated double bond-containing polymer,
(3) The solar cell module having the solar cell module backsheet described in (1) or (2), and (4) the solar cell module described in (3). It is related with the solar cell.

  The back sheet for a solar cell module of the present invention is a case where not only the environment actually used as a solar cell but also an accelerated test in a high-temperature and high-humidity atmosphere studied when evaluating the solar cell module. In addition, it has excellent adhesion and weather resistance to the filler used in the solar cell, maintains an electrical output characteristic, and has an excellent effect of having a good appearance.

  The solar cell module of the present invention can be used not only in an environment where it is actually used as a solar cell, but also in a case where an accelerated test is performed in a high-temperature and high-humidity atmosphere studied when evaluating the solar cell module. It has excellent adhesion and weather resistance to fillers used in batteries, maintains electrical output characteristics, and has an excellent effect of having a good appearance.

  The solar cell of the present invention is used not only in an environment where it is actually used, but also in a solar cell even when an accelerated test is performed in a high-temperature and high-humidity atmosphere that is considered when evaluating solar cell modules. It has excellent adhesion and weather resistance to the filler, maintains an electrical output characteristic, and has an excellent effect of having a good appearance.

It is a schematic sectional drawing which shows one embodiment of the solar cell module backsheet of this invention. It is a schematic sectional drawing which shows another one embodiment of the solar cell module backsheet of this invention.

  The solar cell module backsheet of the present invention is a solar cell module backsheet in which an adhesive layer is formed, and the adhesive layer has an ethylenically unsaturated double bond at the end of the side chain, and has a molecular weight. It is formed with the adhesive for backsheets containing the unsaturated double bond containing polymer whose distribution (weight average molecular weight / number average molecular weight) is 1.5-6.0.

  In the present invention, the unsaturated double bond-containing polymer means a polymer having a vinyl group.

An unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain is, for example,
(A) a polymer obtained by polymerizing a monomer component containing at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer, and a carboxyl group And / or an unsaturated double bond-containing polymer obtained by reacting with a monomer having a hydroxyl group (hereinafter referred to as polymer A),
(B) A polymer obtained by polymerizing a monomer component containing a monomer having a carboxyl group and / or a hydroxyl group, and selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer An unsaturated double bond-containing polymer obtained by reacting with at least one monomer obtained (hereinafter referred to as polymer B),
(C) An unsaturated double obtained by reacting a polymer obtained by polymerizing a monomer component containing a monomer having a carboxyl group and / or a hydroxyl group with an isocyanate group-containing monomer. Bond-containing polymer (hereinafter referred to as polymer C),
(D) Unsaturated double obtained by reacting a polymer obtained by polymerizing a monomer component containing an isocyanate group-containing monomer with a monomer having a carboxyl group and / or a hydroxyl group A bond-containing polymer (hereinafter referred to as polymer D),
(E) an unsaturated double bond-containing polymer (hereinafter referred to as polymer E) obtained by polymerizing a monomer component containing (meth) acrylic acid (vinyloxyalkoxy) alkyl;
(F) Contains unsaturated double bond obtained by reacting a polymer obtained by polymerizing a monomer component containing a monomer having an acid anhydride group and a monomer having a hydroxyl group Polymer (hereinafter referred to as polymer F)
These unsaturated double bond-containing polymers may be used alone or in combination of two or more.

  In the present specification, “(meth) acrylic acid” means acrylic acid and / or methacrylic acid, “(meth) acrylate” means acrylate and / or methacrylate, and “(meth) acryloyl” means acryloyl. And / or methacryloyl.

(A) Polymer A
As described above, the polymer A is obtained by polymerizing a monomer component containing at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer. It is obtained by reacting a polymer obtained with a monomer having a carboxyl group and / or a hydroxyl group.

  Examples of the epoxy group-containing monomer include alkyl groups such as glycidyl acrylate, glycidyl methacrylate, β-methylglycidyl acrylate, β-methylglycidyl methacrylate, β-ethylglycidyl acrylate, and β-ethylglycidyl methacrylate. (Meth) acrylic acid β-alkylglycidyl, allyl acrylate, allyl methacrylate, vinyl benzyl glycidyl ether, allyl (glycidyl) ether, 3-acryloyloxymethyl oxetane, 3-methacryloyloxymethyl oxetane 3-methyl-3-acryloyloxymethyloxetane, 3-methyl-3-methacryloyloxymethyloxetane, 3-ethyl-3-acryloyloxymethyloxetane, 3-ethyl-3-methacryloyloxime Examples include thioxetane, (3,4-epoxycyclohexyl) methyl acrylate, methyl (3,4-epoxycyclohexyl) methyl methacrylate, and vinylcyclohexene oxide, but the present invention is not limited to such examples. Absent. These epoxy group-containing monomers may be used alone or in combination of two or more. Among these epoxy group-containing monomers, glycidyl (meth) acrylate is preferable from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance.

  Examples of the oxazoline group-containing monomer include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, Examples include 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, and 2-isopropenyl-5-ethyl-2-oxazoline. It is not limited to only. These oxazoline group-containing monomers may be used alone or in combination of two or more. Among these oxazoline group-containing monomers, 2-vinyl-2-oxazoline is preferable from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance.

  The epoxy group-containing monomer and the oxazoline group-containing monomer may be used alone or in combination. The monomer component may be composed of only at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer, Other monomers may be included as long as the object of the present invention is not inhibited.

  Examples of the other monomer include a monomer having a carboxyl group, an acidic phosphate ester monomer, a monomer having a group having active hydrogen, a (meth) acrylic acid ester, and a nitrogen atom. Monomers, monomers having two or more polymerizable double bonds, aromatic monomers, monomers having halogen atoms, vinyl ester monomers, vinyl ether monomers, etc. However, the present invention is not limited to such examples. These monomers may be used alone or in combination of two or more.

  Examples of the monomer having a carboxyl group include aliphatic monocarboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, and maleic anhydride, but the present invention is not limited to such examples. Absent. These monomers having a carboxyl group may be used alone or in combination of two or more.

  Examples of acidic phosphate ester monomers include 2-acryloyloxymethyl acid phosphate, 2-methacryloyloxymethyl acid phosphate, 2-acryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, and the like. The present invention is not limited to such examples. These acidic phosphate ester monomers may be used alone or in combination of two or more.

  Examples of the monomer having a group having active hydrogen include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, and hydroxybutyl methacrylate. Hydroxyl group-containing (meth) acrylate ester; α-hydroxymethyl acrylate ester such as methyl α-hydroxymethyl acrylate and ethyl α-hydroxymethyl acrylate; carbon of alkyl group such as caprolactone-modified 2-hydroxyethyl (meth) acrylate Examples thereof include hydroxyl group-containing (meth) acrylic acid esters having 1 to 4 carbon atoms, such as caprolactone-modified hydroxyalkyl (meth) acrylate having 1 to 4 carbon atoms, but the present invention is limited to such examples only. Something No. These monomers having a group having active hydrogen may be used alone or in combination of two or more.

  Examples of (meth) acrylic acid esters include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, and n-acrylate. Alkyl (meth) acrylates having 1 to 8 carbon atoms in alkyl groups such as -butyl, n-butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate Cycloalkyl (meth) acrylate having 3 to 8 carbon atoms of cycloalkyl group such as isobornyl acrylate, isobornyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate; cyclohexylmethyl acrylate, methacrylic acid The number of carbon atoms of the alkyl group such as cyclohexylmethyl, cyclohexylethyl acrylate, cyclohexylethyl methacrylate, cyclohexylpropyl acrylate, cyclohexylpropyl methacrylate, 4-methylcyclohexylmethyl acrylate, 4-methylcyclohexylmethyl methacrylate is 1 to 8 carbon atoms. And cycloalkylalkyl (meth) acrylate having 3 to 8 carbon atoms in the cycloalkyl group, and the like. However, the present invention is not limited to such examples. These (meth) acrylic acid esters may be used alone or in combination of two or more.

  Examples of the monomer having a nitrogen atom include (meth) acrylamide such as acrylamide and methacrylamide, N, N′-dimethylaminoethyl acrylate, N, N′-dimethylaminoethyl methacrylate, and N, N acrylic acid. -Nitrogen atom-containing (meth) acrylic acid esters such as diethylaminoethyl, N, N-diethylaminoethyl methacrylate, acrylic imide, methacrylic imide, etc. are mentioned, but the present invention is not limited to such examples only. Absent. These monomers having a nitrogen atom may be used alone or in combination of two or more.

  Examples of the monomer having two or more polymerizable double bonds include ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate, tripropylene glycol diacrylate, and tripropylene glycol. Examples include dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, and the like, but the present invention is not limited to such examples. These monomers having two or more polymerizable double bonds may be used alone or in combination of two or more.

  Examples of the aromatic monomer include styrene compounds such as styrene and α-methylstyrene, but the present invention is not limited to such examples. These aromatic monomers may be used alone or in combination of two or more.

  Examples of the monomer having a halogen atom include vinyl chloride, but the present invention is not limited to such examples. Only one type of monomer having a halogen atom may be used, or two or more types may be used in combination.

  Examples of the vinyl ester monomer include vinyl acetate, but the present invention is not limited to such examples. Only one type of vinyl ester monomer may be used, or two or more types may be used in combination.

  Examples of the vinyl ether monomer include butyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, and the like, but the present invention is not limited to such examples. These vinyl ether monomers may be used alone or in combination of two or more.

  In addition, from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance, the other monomers include UV-absorbing groups such as benzotriazole monomers, benzophenone monomers, and triazine monomers. A monomer having a UV-stable group may be included. Examples of the monomer having an ultraviolet absorbing group include, for example, Otsuka Chemical Co., Ltd., trade name: RUVA93 [2- (2′-hydroxy-5′-methacryloyloxyethylphenyl) -2H-benzotriazole], Osaka Organic It can be easily obtained commercially as a product name: BP-1A manufactured by Chemical Industry Co., Ltd. Examples of the monomer having a UV-stable group include ADEKA such as ADEKA Corporation, trade names: ADK STAB LA-82, ADK STAB LA-87 [2,2,6,6-hexamethyl-4-piperidyl methacrylate], and the like. It can be easily obtained commercially as a stub series.

The monomer component may contain acrylic acid having a basic structure of bisarylfluorene from the viewpoint of improving hydrolysis resistance and insulation resistance. Acrylic acid having bisarylfluorene as a basic structure is commercially easily available as, for example, Osaka Gas Chemical Co., Ltd., trade names: Ogsol EA-0200, Ogsol EA-0200, Ogsol EA-0500, Ogsol EA-1000, etc. Can be obtained. Examples of the monomer component include cyclohexyl alkyl ester of (meth) acrylic acid, dicyclopentenyl (meth) acrylic acid, dicyclopentenyloxyethyl (meth) as disclosed in JP-A-2002-69130. Acrylic acid, dicyclopentanyl (meth) acrylic acid, tricyclo [5.2.1.0 ^2.6 ] dec-8-yl (meth) acrylic acid, terpene (meth) acrylic acid, and the like can also be contained.

  The content of at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer in the monomer component is a viewpoint of improving adhesiveness, weather resistance and blocking resistance. Therefore, it is preferably 0.5% by mass or more, more preferably 1% by mass or more, further preferably 3% by mass or more, particularly preferably 5% by mass or more, and the upper limit is 100% by mass.

  When polymerizing the monomer component, a chain transfer agent may be used as necessary from the viewpoint of suppressing an increase in molecular weight distribution and gelation. Examples of chain transfer agents include alkyl mercaptans such as n-butyl mercaptan, tert-butyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan, 1,2-dimercaptoethane, and γ-mercaptopropyltrimethoxysilane. However, the present invention is not limited to such examples. These chain transfer agents may be used alone or in combination of two or more. Among these chain transfer agents, mercaptocarboxylic acids, mercaptocarboxylic acid esters, alkyl mercaptans are obtained because they are easily available, have excellent anti-crosslinking properties, and have a low degree of decrease in polymerization rate. Compounds having a mercapto group such as mercaptoalcohols, aromatic mercaptans and mercaptoisocyanurates are preferred.

  The amount of the chain transfer agent may be appropriately set according to the composition of the monomer component, the polymerization conditions such as the polymerization temperature, the molecular weight of the target polymer, etc., and is not particularly limited, but the weight average molecular weight is several thousand to When obtaining tens of thousands of polymers, the amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass per 100 parts by mass of the monomer component.

  Examples of the method for polymerizing the monomer component include a solution polymerization method, a bulk polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method, but the present invention is limited only to such examples. It is not a thing.

  When the monomer component is polymerized by a solution polymerization method, examples of the solvent include aromatic solvents such as toluene and xylene; alcohol solvents such as isopropyl alcohol and n-butyl alcohol; propylene glycol methyl ether and dipropylene glycol methyl. Ether solvents such as ether, ethyl cellosolve, butyl cellosolve; ester solvents such as ethyl acetate, butyl acetate, cellosolve acetate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diacetone alcohol; amide solvents such as dimethylformamide However, the present invention is not limited to such examples. These solvents may be used alone or in combination of two or more. The amount of the solvent may be appropriately determined in consideration of the polymerization conditions, the composition of the monomer components, the concentration of the resulting polymer, and the like.

  A polymerization initiator can be used when the monomer component is polymerized. Examples of the polymerization initiator include 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile), tert-butylperoxy-2-ethylhexano And 2,2′-azobisisobutyronitrile, benzoyl peroxide, di-tert-butyl peroxide, and the like, but the present invention is not limited to such examples. These polymerization initiators may be used alone or in combination of two or more. The amount of the polymerization initiator may be appropriately set according to the desired physical properties of the polymer to be obtained, but is usually preferably 0.01 to 50 parts by mass, more preferably 100 parts by mass of the monomer component. 0.05 to 20 parts by mass.

  The polymerization conditions for polymerizing the monomer components may be set as appropriate according to the polymerization method, and are not particularly limited. The polymerization temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that the polymerization reaction of a monomer component may be completed. Moreover, it is preferable that the atmosphere in superposition | polymerization is inert gas, such as nitrogen gas and argon gas, for example.

  Next, the weight obtained by polymerizing the monomer component containing at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer as described above. The coalescence is reacted with a monomer having a carboxyl group and / or a hydroxyl group.

  Examples of the monomer having a carboxyl group and / or a hydroxyl group include a monomer having a carboxyl group, a monomer having a hydroxyl group, and a monomer having a carboxyl group and a hydroxyl group. These monomers may be used alone or in combination of two or more.

  Examples of the monomer having a carboxyl group include aliphatic monocarboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, and maleic anhydride, but the present invention is not limited to such examples. Absent. These monomers having a carboxyl group may be used alone or in combination of two or more.

  Examples of the monomer having a hydroxyl group include carbons of alkyl groups such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, and hydroxybutyl methacrylate. 1 to 4 (meth) acrylic acid hydroxyalkyl; caprolactone-modified 2-hydroxyethyl acrylate, caprolactone-modified 2-hydroxyethyl methacrylate and other alkyl groups having 1 to 4 carbon atoms such as caprolactone-modified hydroxyalkyl (meth) acrylate Hydroxyl group-containing (meth) acrylic acid ester having 1 to 4 carbon atoms of alkyl group; methyl α-hydroxymethyl acrylate, methyl α-hydroxymethyl methacrylate, α-hydroxymethyl acrylic acid Chill, alpha-hydroxy number of carbon atoms in each alkyl group such as methyl ethyl methacrylate but like 1-4 alpha-hydroxyalkyl alkyl acrylate, the present invention is not limited only to those exemplified. These monomers having a hydroxyl group may be used alone or in combination of two or more. Caprolactone-modified hydroxy (meth) acrylate can be easily obtained commercially, for example, as trade name: Plaxel FM1, Plaxel FM1D, Plaxel FM2D, Plaxel FM3, Plaxel FA1DM, Plaxel FA2D manufactured by Daicel Chemical Industries, Ltd. it can.

  Among the monomers having a carboxyl group and / or a hydroxyl group, (meth) acrylic acid is preferable from the viewpoint of improving adhesiveness, weather resistance and blocking resistance.

  The ratio of the polymer to the monomer having a carboxyl group and / or a hydroxyl group is such that the monomer having a carboxyl group and / or a hydroxyl group per mole of the total amount of the epoxy group and the oxazoline group possessed by the polymer. It is desirable to adjust the total amount of the carboxyl group and the hydroxyl group to be preferably 0.1 to 3 mol, more preferably 0.5 to 1.5 mol.

  When reacting the polymer with a monomer having a carboxyl group and / or a hydroxyl group, it is preferable to add an esterification catalyst, a polymerization inhibitor, or the like to the monomer having a carboxyl group and / or a hydroxyl group.

  Examples of the esterification catalyst include organic acid metal salts such as zinc octenoate, phosphonium compounds such as triphenylphosphine, tetraphenylphosphonium chloride, tetraphenylphosphonium bromide, tetraphenylphosphonium iodide, and tetrabutylphosphonium bromide. However, the present invention is not limited to such examples. These esterification catalysts may be used alone or in combination of two or more.

  Since the amount of the esterification catalyst varies depending on the type of the esterification catalyst, it cannot be determined unconditionally, but is usually preferably 0.01 to 5 parts by mass, more preferably 0.1 to 5 parts by mass per 100 parts by mass of the polymer. 3 parts by mass.

  Examples of the polymerization inhibitor include methoxyphenol; quinones such as hydroquinone, benzoquinone, and p-tert-butylcatechol, but the present invention is not limited to such examples. These polymerization inhibitors may be used alone or in combination of two or more.

  The amount of the polymerization inhibitor improves the yield, suppresses the polymerization of the monomer having a carboxyl group and / or a hydroxyl group, and maintains the reactivity with the polymer, so that the carboxyl group and / or the hydroxyl group is maintained. Preferably it is 0.01-10000 ppm, More preferably, it is 0.1-7000 ppm, More preferably, it is 1-5000 ppm with respect to the monomer which has this.

  The reaction between the polymer and a monomer having a carboxyl group and / or a hydroxyl group is carried out, for example, by adding a monomer having a carboxyl group and / or a hydroxyl group to the reaction mixture from which the polymer is obtained. be able to.

  The reaction conditions for reacting the polymer with a monomer having a carboxyl group and / or a hydroxyl group may be appropriately set according to the reaction method, and are not particularly limited. The reaction temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that reaction may be completed. The atmosphere during the reaction is not particularly limited and may be air, for example, an inert gas such as nitrogen gas or argon gas, or a mixed gas of oxygen and inert gas. There may be.

  As described above, the polymer A is obtained by reacting the polymer with a monomer having a carboxyl group and / or a hydroxyl group. The lower limit of the weight average molecular weight of the polymer A is preferably 4000 or more, more preferably 5000 or more, further preferably 7000 or more, and the upper limit is preferably 1,000,000 or less, more preferably 600,000 or less, Preferably it is 400,000 or less. The weight average molecular weight is a value when measured by gel permeation chromatography (GPC) with a polystyrene standard.

  The acid value or hydroxyl value of the polymer A (nonvolatile component) is preferably 0.1 to 200 mgKOH / g, more preferably 1 to 100 mgKOH / g, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance. More preferably, it is 3-60 mgKOH / g.

(B) Polymer B
As described above, the polymer B includes a polymer obtained by polymerizing a monomer component containing a monomer having a carboxyl group and / or a hydroxyl group, an epoxy group-containing monomer, and an oxazoline group-containing monomer. It is obtained by reacting with at least one monomer selected from the group consisting of monomers.

  Examples of the monomer having a carboxyl group and / or a hydroxyl group include the same monomers as those having a carboxyl group and / or a hydroxyl group used in preparing the polymer A. More specifically, examples of the monomer having a carboxyl group and / or a hydroxyl group include a monomer having a carboxyl group, a monomer having a hydroxyl group, and a monomer having a carboxyl group and a hydroxyl group. These monomers may be used alone or in combination of two or more.

  Examples of the monomer having a carboxyl group include aliphatic monocarboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, and maleic anhydride, but the present invention is not limited to such examples. Absent. These monomers having a carboxyl group may be used alone or in combination of two or more.

  Examples of the monomer having a hydroxyl group include carbons of alkyl groups such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, and hydroxybutyl methacrylate. 1 to 4 (meth) acrylic acid hydroxyalkyl; caprolactone-modified 2-hydroxyethyl acrylate, caprolactone-modified 2-hydroxyethyl methacrylate and other alkyl groups having 1 to 4 carbon atoms such as caprolactone-modified hydroxyalkyl (meth) acrylate Hydroxyl group-containing (meth) acrylic acid ester having 1 to 4 carbon atoms of alkyl group; methyl α-hydroxymethyl acrylate, methyl α-hydroxymethyl methacrylate, α-hydroxymethyl acrylic acid Chill, alpha-hydroxy number of carbon atoms in each alkyl group such as methyl ethyl methacrylate but like 1-4 alpha-hydroxyalkyl alkyl acrylate, the present invention is not limited only to those exemplified. These monomers having a hydroxyl group may be used alone or in combination of two or more. Caprolactone-modified hydroxy (meth) acrylate can be easily obtained commercially, for example, as trade name: Plaxel FM1, Plaxel FM1D, Plaxel FM2D, Plaxel FM3, Plaxel FA1DM, Plaxel FA2D manufactured by Daicel Chemical Industries, Ltd. it can.

  Among monomers having a carboxyl group and / or a hydroxyl group, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance, a hydroxyl group-containing (meth) acrylic acid ester preferably having an alkyl group having 1 to 18 carbon atoms More preferably, the hydroxyl group-containing (meth) acrylic acid ester having 1 to 12 carbon atoms in the alkyl group, even more preferably the hydroxyl group-containing (meth) acrylic acid ester having 1 to 6 carbon atoms in the alkyl group, more preferably alkyl. It is a hydroxyl group-containing (meth) acrylic acid ester having 1 to 4 carbon atoms.

  The monomer component may contain other monomers as long as the object of the present invention is not impaired. Other monomers include, for example, acidic phosphate ester monomers, (meth) acrylic acid esters, monomers having an epoxy group, monomers having a nitrogen atom, two or more polymerizable doubles Examples include a monomer having a bond, an aromatic monomer, a monomer having a halogen atom, a vinyl ester monomer, and a vinyl ether monomer, but the present invention is limited only to such examples. It is not something. These monomers may be used alone or in combination of two or more.

  The acidic phosphate ester monomer, (meth) acrylic acid ester, monomer having nitrogen atom, monomer having two or more polymerizable double bonds, aromatic monomer, halogen atom Examples of the monomer, vinyl ester monomer, and vinyl ether monomer that are included are the same as the other monomers used in preparing the polymer A.

  Examples of the monomer having an epoxy group include epoxy group-containing (meth) acrylic acid esters such as glycidyl acrylate and glycidyl methacrylate, but the present invention is not limited to such examples. . These monomers having an epoxy group may be used alone or in combination of two or more.

  Among the other monomers, from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance, (meth) acrylic acid esters are preferable, and (meth) acrylic acid alkyl and (meth) acrylic acid cycloalkyl are more preferable. preferable.

  In addition, from the viewpoint of improving weather resistance and blocking resistance, the other monomer may be a monomer having an ultraviolet absorbing group such as a benzotriazole monomer, a benzophenone monomer, or a triazine monomer. A monomer; a monomer having an ultraviolet-stable group may be included. Examples of the monomer having a UV-absorbing group and the monomer having a UV-stable group are the same as those used in preparing the polymer A.

  The monomer component may contain acrylic acid having a basic structure of bisarylfluorene from the viewpoint of improving hydrolysis resistance and insulation resistance. Examples of the acrylic acid having bisarylfluorene as a basic structure are the same as those used in preparing the polymer A.

  The content of the monomer having a carboxyl group and / or a hydroxyl group in the monomer component is preferably 0.5% by mass or more, more preferably 1% by mass or more, and further preferably from the viewpoint of improving adhesiveness. It is 3% by mass or more, particularly preferably 5% by mass or more, and the upper limit is 100% by mass.

  When polymerizing the monomer component, a chain transfer agent may be used as necessary from the viewpoint of suppressing an increase in molecular weight distribution and gelation. Examples of the chain transfer agent are the same as those used in preparing the polymer A.

  The amount of the chain transfer agent may be appropriately set according to the composition of the monomer component, the polymerization conditions such as the polymerization temperature, the molecular weight of the target polymer, etc., and is not particularly limited, but the weight average molecular weight is several thousand to When obtaining tens of thousands of polymers, the amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass per 100 parts by mass of the monomer component.

  Examples of the method for polymerizing the monomer component include a solution polymerization method, a bulk polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method, but the present invention is limited only to such examples. It is not a thing.

  Examples of the solvent used when the monomer component is polymerized by the solution polymerization method are the same as those used when the polymer A is prepared.

  A polymerization initiator can be used when the monomer component is polymerized. As a polymerization initiator, the same thing as used when preparing the said polymer A is illustrated. The amount of the polymerization initiator may be appropriately set according to the desired physical properties of the polymer to be obtained. Usually, it is preferably 0.05 to 30 parts by mass, more preferably 100 parts by mass of the monomer component. 0.15 to 10 parts by mass.

  The polymerization conditions for polymerizing the monomer components may be set as appropriate according to the polymerization method, and are not particularly limited. The polymerization temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that the polymerization reaction of a monomer component may be completed. Moreover, it is preferable that the atmosphere in superposition | polymerization is inert gas, such as nitrogen gas and argon gas, for example.

  Next, a polymer obtained by polymerizing a monomer component containing a monomer having a carboxyl group and / or a hydroxyl group as described above, an epoxy group-containing monomer, and an oxazoline group-containing monomer And at least one monomer selected from the group consisting of:

  The epoxy group-containing monomer and the oxazoline group-containing monomer may be used alone or in combination of two or more.

  Examples of the epoxy group-containing monomer include alkyl groups such as glycidyl acrylate, glycidyl methacrylate, β-methylglycidyl acrylate, β-methylglycidyl methacrylate, β-ethylglycidyl acrylate, and β-ethylglycidyl methacrylate. (Meth) acrylic acid β-alkylglycidyl, allyl acrylate, allyl methacrylate, vinyl benzyl glycidyl ether, allyl (glycidyl) ether, 3-acryloyloxymethyl oxetane, 3-methacryloyloxymethyl oxetane 3-methyl-3-acryloyloxymethyloxetane, 3-methyl-3-methacryloyloxymethyloxetane, 3-ethyl-3-acryloyloxymethyloxetane, 3-ethyl-3-methacryloyloxime Examples include thioxetane, (3,4-epoxycyclohexyl) methyl acrylate, methyl (3,4-epoxycyclohexyl) methyl methacrylate, and vinylcyclohexene oxide, but the present invention is not limited to such examples. Absent. These epoxy group-containing monomers may be used alone or in combination of two or more. Among these epoxy group-containing monomers, glycidyl (meth) acrylate is preferable from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance.

  Examples of the oxazoline group-containing monomer include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, Examples include 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, and 2-isopropenyl-5-ethyl-2-oxazoline. It is not limited to only. These oxazoline group-containing monomers may be used alone or in combination of two or more. Among these oxazoline group-containing monomers, 2-vinyl-2-oxazoline is preferable from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance.

  The reaction of the polymer with at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer can be carried out, for example, by adding epoxy to the reaction mixture from which the polymer is obtained. It can be performed by adding at least one monomer selected from the group consisting of a group-containing monomer and an oxazoline group-containing monomer.

  The reaction conditions for reacting the polymer with at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer are appropriately set according to the reaction method. There is no particular limitation. The reaction temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that reaction may be completed. The atmosphere during the reaction is not particularly limited and may be air, for example, an inert gas such as nitrogen gas or argon gas, or a mixed gas of oxygen and inert gas. There may be.

  Polymer B is obtained by reacting the polymer with at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer as described above. The lower limit of the weight average molecular weight of the polymer B is preferably 4000 or more, more preferably 5000 or more, and further preferably 7000 or more. The upper limit is preferably 1,000,000 or less, more preferably 600,000 or less, Preferably it is 400,000 or less. The weight average molecular weight is a value when measured by gel permeation chromatography (GPC) with a polystyrene standard.

  The acid value or hydroxyl value of the polymer B (nonvolatile content) is preferably 0.1 to 200 mgKOH / g, more preferably 1 to 100 mgKOH / g, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance. More preferably, it is 3-60 mgKOH / g.

(C) Polymer C
As described above, the polymer C is obtained by reacting a polymer obtained by polymerizing a monomer component containing a monomer having a carboxyl group and / or a hydroxyl group with an isocyanate group-containing monomer. can get.

  Examples of the monomer having a carboxyl group and / or a hydroxyl group include the same monomers as those having a carboxyl group and / or a hydroxyl group used in preparing the polymer A. More specifically, examples of the monomer having a carboxyl group and / or a hydroxyl group include a monomer having a carboxyl group, a monomer having a hydroxyl group, and a monomer having a carboxyl group and a hydroxyl group. These monomers may be used alone or in combination of two or more.

  Examples of the monomer having a carboxyl group include aliphatic monocarboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, and maleic anhydride, but the present invention is not limited to such examples. Absent. These monomers having a carboxyl group may be used alone or in combination of two or more.

  Examples of the monomer having a hydroxyl group include carbons of alkyl groups such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, and hydroxybutyl methacrylate. 1 to 4 (meth) acrylic acid hydroxyalkyl; caprolactone-modified 2-hydroxyethyl acrylate, caprolactone-modified 2-hydroxyethyl methacrylate and other alkyl groups having 1 to 4 carbon atoms such as caprolactone-modified hydroxyalkyl (meth) acrylate Hydroxyl group-containing (meth) acrylic acid ester having 1 to 4 carbon atoms of alkyl group; methyl α-hydroxymethyl acrylate, methyl α-hydroxymethyl methacrylate, α-hydroxymethyl acrylic acid Chill, alpha-hydroxy number of carbon atoms in each alkyl group such as methyl ethyl methacrylate but like 1-4 alpha-hydroxyalkyl alkyl acrylate, the present invention is not limited only to those exemplified. These monomers having a hydroxyl group may be used alone or in combination of two or more. Caprolactone-modified hydroxy (meth) acrylate can be easily obtained commercially, for example, as trade name: Plaxel FM1, Plaxel FM1D, Plaxel FM2D, Plaxel FM3, Plaxel FA1DM, Plaxel FA2D manufactured by Daicel Chemical Industries, Ltd. it can.

  Among monomers having a carboxyl group and / or a hydroxyl group, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance, a hydroxyl group-containing (meth) acrylic acid ester preferably having an alkyl group having 1 to 18 carbon atoms More preferably, the hydroxyl group-containing (meth) acrylic acid ester having 1 to 12 carbon atoms in the alkyl group, even more preferably the hydroxyl group-containing (meth) acrylic acid ester having 1 to 6 carbon atoms in the alkyl group, more preferably alkyl. It is a hydroxyl group-containing (meth) acrylic acid ester having 1 to 4 carbon atoms.

  The monomer component may contain other monomers as long as the object of the present invention is not impaired. Other monomers include, for example, acidic phosphate ester monomers, (meth) acrylic acid esters, monomers having an epoxy group, monomers having a nitrogen atom, two or more polymerizable doubles Examples include a monomer having a bond, an aromatic monomer, a monomer having a halogen atom, a vinyl ester monomer, and a vinyl ether monomer, but the present invention is limited only to such examples. It is not something. These monomers may be used alone or in combination of two or more.

  The acidic phosphate ester monomer, (meth) acrylic acid ester, monomer having nitrogen atom, monomer having two or more polymerizable double bonds, aromatic monomer, halogen atom Examples of the monomer, vinyl ester monomer, and vinyl ether monomer that are included are the same as the other monomers used in preparing the polymer A.

  Examples of the monomer having an epoxy group include epoxy group-containing (meth) acrylic acid esters such as glycidyl acrylate and glycidyl methacrylate, but the present invention is not limited to such examples. . These monomers having an epoxy group may be used alone or in combination of two or more.

  Among the other monomers, from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance, (meth) acrylic acid esters are preferable, and (meth) acrylic acid alkyl and (meth) acrylic acid cycloalkyl are more preferable. preferable.

  In addition, from the viewpoint of improving weather resistance and blocking resistance, the other monomer may be a monomer having an ultraviolet absorbing group such as a benzotriazole monomer, a benzophenone monomer, or a triazine monomer. A monomer; a monomer having an ultraviolet-stable group may be included. Examples of the monomer having a UV-absorbing group and the monomer having a UV-stable group are the same as those used in preparing the polymer A.

  The monomer component may contain acrylic acid having a basic structure of bisarylfluorene from the viewpoint of improving hydrolysis resistance and insulation resistance. Examples of the acrylic acid having bisarylfluorene as a basic structure are the same as those used in preparing the polymer A.

  The content of the monomer having a carboxyl group and / or a hydroxyl group in the monomer component is preferably 0.5% by mass or more, more preferably 1% by mass or more, and further preferably from the viewpoint of improving adhesiveness. It is 3% by mass or more, particularly preferably 5% by mass or more, and the upper limit is 100% by mass.

  When polymerizing the monomer component, a chain transfer agent may be used as necessary from the viewpoint of suppressing an increase in molecular weight distribution and gelation. Examples of the chain transfer agent are the same as those used in preparing the polymer A.

  The amount of the chain transfer agent may be appropriately set according to the composition of the monomer component, the polymerization conditions such as the polymerization temperature, the molecular weight of the target polymer, etc., and is not particularly limited, but the weight average molecular weight is several thousand to When obtaining tens of thousands of polymers, the amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass per 100 parts by mass of the monomer component.

  Examples of the method for polymerizing the monomer component include a solution polymerization method, a bulk polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method, but the present invention is limited only to such examples. It is not a thing.

  Examples of the solvent used when the monomer component is polymerized by the solution polymerization method are the same as those used when the polymer A is prepared.

  A polymerization initiator can be used when the monomer component is polymerized. As a polymerization initiator, the same thing as used when preparing the said polymer A is illustrated. The amount of the polymerization initiator may be appropriately set according to the desired physical properties of the polymer to be obtained. Usually, it is preferably 0.05 to 30 parts by mass, more preferably 100 parts by mass of the monomer component. 0.15 to 10 parts by mass.

  The polymerization conditions for polymerizing the monomer components may be set as appropriate according to the polymerization method, and are not particularly limited. The polymerization temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that the polymerization reaction of a monomer component may be completed. Moreover, it is preferable that the atmosphere in superposition | polymerization is inert gas, such as nitrogen gas and argon gas, for example.

  Next, the polymer obtained by polymerizing the monomer component containing the monomer having a carboxyl group and / or a hydroxyl group as described above is reacted with the isocyanate group-containing monomer.

  Examples of the isocyanate group-containing monomer include acryloyloxymethyl isocyanate, methacryloyloxymethyl isocyanate, 2-acryloyloxyethyl isocyanate, 2-methacryloyloxyethyl isocyanate, 3-acryloyloxypropyl isocyanate, and 3-methacryloyloxypropyl isocyanate. Examples of the alkyl group include (meth) acryloyloxyalkyl isocyanate having 1 to 4 carbon atoms and 3-isopropenyl-α, α-dimethylbenzyl isocyanate, but the present invention is not limited to such examples. . These monomers having a carboxyl group may be used alone or in combination of two or more.

  A catalyst is preferably used when the polymer and the isocyanate group-containing monomer are reacted.

  Examples of the catalyst include dialkyltin dicarboxylates such as dibutyltin dilaurate, dibutyltin dineodecanoate, and dibutyltin diacetate, but the present invention is not limited to such examples. Since the amount of the catalyst varies depending on the type and the like, it cannot be determined unconditionally. 0 to 1 part by mass.

  The reaction between the polymer and the isocyanate group-containing monomer can be performed, for example, by adding an isocyanate group-containing monomer to the reaction mixture from which the polymer is obtained.

  The ratio of the polymer and the isocyanate group-containing monomer is the equivalent ratio of the carboxyl group and / or hydroxyl group of the polymer to the isocyanate group of the isocyanate group-containing monomer (equivalent of NCO group / carboxyl group and The total equivalent weight of the hydroxyl groups) is preferably adjusted to be 0.1 to 5, more preferably 0.2 to 3.

  The reaction conditions for reacting the polymer with the isocyanate group-containing monomer are not particularly limited, and may be set as appropriate according to the reaction method. The reaction temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that reaction may be completed. The atmosphere during the reaction is not particularly limited and may be air, for example, an inert gas such as nitrogen gas or argon gas, or a mixed gas of oxygen and inert gas. There may be.

  The polymer C is obtained by reacting the polymer with the isocyanate group-containing monomer as described above. The lower limit of the weight average molecular weight of the polymer C is preferably 4000 or more, more preferably 5000 or more, further preferably 7000 or more, and the upper limit is preferably 1,000,000 or less, more preferably 600,000 or less, Preferably it is 400,000 or less. The weight average molecular weight is a value when measured by gel permeation chromatography (GPC) with a polystyrene standard.

  In addition, the hydroxyl value of the polymer C (nonvolatile content) is preferably 0.4 to 200 mgKOH / g, more preferably 1 to 100 KOH / g, and still more preferably, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance. Is 3-60 mg KOH / g.

(D) Polymer D
As described above, the polymer D is obtained by reacting a polymer obtained by polymerizing a monomer component containing an isocyanate group-containing monomer with a monomer having a carboxyl group and / or a hydroxyl group. Obtained by.

  As an isocyanate group containing monomer, the thing similar to the isocyanate group containing monomer used when preparing the said polymer C is illustrated. More specifically, for example, alkyl groups such as acryloyloxymethyl isocyanate, methacryloyloxymethyl isocyanate, 2-acryloyloxyethyl isocyanate, 2-methacryloyloxyethyl isocyanate, 3-acryloyloxypropyl isocyanate, 3-methacryloyloxypropyl isocyanate, etc. Examples thereof include (meth) acryloyloxyalkyl isocyanate having 1 to 4 carbon atoms and 3-isopropenyl-α, α-dimethylbenzyl isocyanate, but the present invention is not limited only to such examples. These monomers having a carboxyl group may be used alone or in combination of two or more.

  The monomer component may contain other monomers as long as the object of the present invention is not impaired. Other monomers include, for example, acidic phosphate ester monomers, (meth) acrylic acid esters, monomers having nitrogen atoms, monomers having two or more polymerizable double bonds, aromatics Examples include group-based monomers, monomers having halogen atoms, vinyl ester monomers, vinyl ether monomers, and the like, but the present invention is not limited to such examples. These monomers may be used alone or in combination of two or more.

  Acid phosphate ester monomer, (meth) acrylic acid ester, monomer having epoxy group, monomer having nitrogen atom, monomer having two or more polymerizable double bonds, aromatic Examples of the monomer, the monomer having a halogen atom, the vinyl ester monomer and the vinyl ether monomer are the same as other monomers used in preparing the polymer A. The

  Among the other monomers, from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance, (meth) acrylic acid esters are preferable, and (meth) acrylic acid alkyl and (meth) acrylic acid cycloalkyl are more preferable. preferable.

  In addition, from the viewpoint of improving weather resistance and blocking resistance, the other monomer may be a monomer having an ultraviolet absorbing group such as a benzotriazole monomer, a benzophenone monomer, or a triazine monomer. A monomer; a monomer having an ultraviolet-stable group may be included. Examples of the monomer having a UV-absorbing group and the monomer having a UV-stable group are the same as those used in preparing the polymer A.

  The monomer component may contain acrylic acid having a basic structure of bisarylfluorene from the viewpoint of improving hydrolysis resistance and insulation resistance. Examples of the acrylic acid having bisarylfluorene as a basic structure are the same as those used in preparing the polymer A.

  The content of the isocyanate group-containing monomer in the monomer component is preferably 0.5% by mass or more, more preferably 1% by mass or more, further preferably 3% by mass or more, from the viewpoint of improving adhesiveness. Especially preferably, it is 5 mass% or more, and the upper limit is 100 mass%.

  When polymerizing the monomer component, a chain transfer agent may be used as necessary from the viewpoint of suppressing an increase in molecular weight distribution and gelation. Examples of the chain transfer agent are the same as those used in preparing the polymer A.

  The amount of the chain transfer agent may be appropriately set according to the composition of the monomer component, the polymerization conditions such as the polymerization temperature, the molecular weight of the target polymer, etc., and is not particularly limited, but the weight average molecular weight is several thousand to When obtaining tens of thousands of polymers, the amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass per 100 parts by mass of the monomer component.

  Examples of the method for polymerizing the monomer component include a solution polymerization method, a bulk polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method, but the present invention is limited only to such examples. It is not a thing.

  Examples of the solvent used when the monomer component is polymerized by the solution polymerization method are the same as those used when the polymer A is prepared.

  A polymerization initiator can be used when the monomer component is polymerized. As a polymerization initiator, the same thing as used when preparing the said polymer A is illustrated. The amount of the polymerization initiator may be appropriately set according to the desired physical properties of the polymer to be obtained. Usually, it is preferably 0.05 to 30 parts by mass, more preferably 100 parts by mass of the monomer component. 0.15 to 10 parts by mass.

  The polymerization conditions for polymerizing the monomer components may be set as appropriate according to the polymerization method, and are not particularly limited. The polymerization temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that the polymerization reaction of a monomer component may be completed. Moreover, it is preferable that the atmosphere in superposition | polymerization is inert gas, such as nitrogen gas and argon gas, for example.

  Next, the polymer obtained by polymerizing the monomer component containing the isocyanate group-containing monomer as described above is reacted with a monomer having a carboxyl group and / or a hydroxyl group.

  Examples of the monomer having a carboxyl group and / or a hydroxyl group include the same monomers as those having a carboxyl group and / or a hydroxyl group used in preparing the polymer A. More specifically, examples of the monomer having a carboxyl group and / or a hydroxyl group include a monomer having a carboxyl group, a monomer having a hydroxyl group, and a monomer having a carboxyl group and a hydroxyl group. These monomers may be used alone or in combination of two or more.

  Examples of the monomer having a carboxyl group include aliphatic monocarboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, and maleic anhydride, but the present invention is not limited to such examples. Absent. These monomers having a carboxyl group may be used alone or in combination of two or more.

  Examples of the monomer having a hydroxyl group include carbons of alkyl groups such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, and hydroxybutyl methacrylate. 1 to 4 (meth) acrylic acid hydroxyalkyl; caprolactone-modified 2-hydroxyethyl acrylate, caprolactone-modified 2-hydroxyethyl methacrylate and other alkyl groups having 1 to 4 carbon atoms such as caprolactone-modified hydroxyalkyl (meth) acrylate Hydroxyl group-containing (meth) acrylic acid ester having 1 to 4 carbon atoms of alkyl group; methyl α-hydroxymethyl acrylate, methyl α-hydroxymethyl methacrylate, α-hydroxymethyl acrylic acid Chill, alpha-hydroxy number of carbon atoms in each alkyl group such as methyl ethyl methacrylate but like 1-4 alpha-hydroxyalkyl alkyl acrylate, the present invention is not limited only to those exemplified. These monomers having a hydroxyl group may be used alone or in combination of two or more. Caprolactone-modified hydroxy (meth) acrylate can be easily obtained commercially, for example, as trade name: Plaxel FM1, Plaxel FM1D, Plaxel FM2D, Plaxel FM3, Plaxel FA1DM, Plaxel FA2D manufactured by Daicel Chemical Industries, Ltd. it can.

  Among monomers having a carboxyl group and / or a hydroxyl group, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance, a hydroxyl group-containing (meth) acrylic acid ester preferably having an alkyl group having 1 to 18 carbon atoms More preferably, the hydroxyl group-containing (meth) acrylic acid ester having 1 to 12 carbon atoms in the alkyl group, even more preferably the hydroxyl group-containing (meth) acrylic acid ester having 1 to 6 carbon atoms in the alkyl group, more preferably alkyl. It is a hydroxyl group-containing (meth) acrylic acid ester having 1 to 4 carbon atoms.

  When the polymer is reacted with a monomer having a carboxyl group and / or a hydroxyl group, a catalyst is preferably used.

  Examples of the catalyst include dialkyltin dicarboxylates such as dibutyltin dilaurate, dibutyltin dineodecanoate, and dibutyltin diacetate, but the present invention is not limited to such examples. Since the amount of the catalyst varies depending on the type and the like, it cannot be determined unconditionally, but usually, per 100 parts by mass of the monomer having a carboxyl group and / or a hydroxyl group, preferably 0.005 to 5 parts by mass, More preferably, it is 0.01-3 mass parts.

  The reaction between the polymer and a monomer having a carboxyl group and / or a hydroxyl group is carried out, for example, by adding a monomer having a carboxyl group and / or a hydroxyl group to the reaction mixture from which the polymer is obtained. be able to.

  The ratio between the polymer and the monomer having a carboxyl group and / or a hydroxyl group is equivalent to the carboxyl group and / or the hydroxyl group of the polymer and the isocyanate group of the monomer having a carboxyl group and / or a hydroxyl group. The ratio (equivalent of NCO group / total equivalent of carboxyl group and hydroxyl group) is preferably adjusted to be 0.1 to 5, more preferably 0.2 to 3.

  The reaction conditions for reacting the polymer with a monomer having a carboxyl group and / or a hydroxyl group may be appropriately set according to the reaction method, and are not particularly limited. The reaction temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that reaction may be completed. The atmosphere during the reaction is not particularly limited and may be air, for example, an inert gas such as nitrogen gas or argon gas, or a mixed gas of oxygen and inert gas. There may be.

  As described above, the polymer D is obtained by reacting the polymer with a monomer having a carboxyl group and / or a hydroxyl group. The lower limit of the weight average molecular weight of the polymer D is preferably 4000 or more, more preferably 5000 or more, further preferably 7000 or more, and the upper limit is preferably 1 million or less, more preferably 600,000 or less, Preferably it is 400,000 or less. The weight average molecular weight is a value when measured by gel permeation chromatography (GPC) with a polystyrene standard.

  Further, the hydroxyl value of the polymer D (nonvolatile component) is preferably 0.4 to 200 mgKOH / g, more preferably 1 to 100 KOH / g, and further preferably, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance. Is 3-60 mg KOH / g.

(E) Polymer E
As described above, the polymer E is obtained by polymerizing a monomer component containing (meth) acrylic acid (vinyloxyalkoxy) alkyl.

  Examples of (meth) acrylic acid (vinyloxyalkoxy) alkyl include, for example, methyl (vinyloxymethoxy) acrylate, methyl (vinyloxymethoxy) methacrylate, ethyl (vinyloxyethoxy) methacrylate, and methacrylic acid (vinyloxyethoxy). (Meth) acrylic acid (vinyloxyalkoxy) alkyl having 1 to 4 carbon atoms of an alkoxy group such as ethyl and 1 to 4 carbon atoms of an alkyl group can be mentioned. It is not limited. In addition, (meth) acrylic acid (vinyloxyalkoxy) alkyl can be easily obtained commercially as, for example, manufactured by Nippon Shokubai Co., Ltd., product number: VEEA [2- (2-vinyloxyethoxy) ethyl acrylate]. be able to.

  The monomer component may contain other monomers as long as the object of the present invention is not impaired. Other monomers include, for example, a monomer having a carboxyl group, an acidic phosphate monomer, a monomer having a group having active hydrogen, a (meth) acrylic acid ester, and a monomer having an epoxy group. Monomer, monomer having nitrogen atom, monomer having two or more polymerizable double bonds, aromatic monomer, monomer having halogen atom, vinyl ester monomer, vinyl ether Although a monomer etc. are mentioned, this invention is not limited only to this illustration.

  The acidic phosphate ester monomer, (meth) acrylic acid ester, monomer having nitrogen atom, monomer having two or more polymerizable double bonds, aromatic monomer, halogen atom Examples of the monomer, vinyl ester monomer, and vinyl ether monomer that are included are the same as the other monomers used in preparing the polymer A. Moreover, as the monomer which has the said epoxy group, the same thing as the other monomer used when preparing the said polymer C is illustrated.

  Among the other monomers, vinyl ether monomers are preferable, and alkyl vinyl ethers having 1 to 8 carbon atoms and alkyl groups such as butyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, and the like. The cycloalkyl vinyl ether of -12 is more preferable, and the alkyl vinyl ether whose alkyl group has 4-8 carbon atoms is more preferable.

  In addition, from the viewpoint of improving adhesiveness, weather resistance, and blocking resistance, the other monomers include UV-absorbing groups such as benzotriazole monomers, benzophenone monomers, and triazine monomers. A monomer having a UV-stable group may be included. Examples of the monomer having a UV-absorbing group and the monomer having a UV-stable group are the same as those used in preparing the polymer A.

  In addition, the monomer component may contain acrylic acid having bisarylfluorene as a basic structure from the viewpoint of improving adhesiveness, hydrolysis resistance, and insulation resistance. Examples of the acrylic acid having bisarylfluorene as a basic structure are the same as those used in preparing the polymer A.

  The content of (meth) acrylic acid (vinyloxyalkoxy) alkyl in the monomer component is preferably 0.5% by mass or more, more preferably 1% by mass or more, and further preferably 3 from the viewpoint of improving adhesiveness. The upper limit is 100% by mass or more, particularly preferably 5% by mass or more.

  When polymerizing the monomer component, a chain transfer agent may be used as necessary from the viewpoint of suppressing an increase in molecular weight distribution and gelation. Examples of the chain transfer agent are the same as those used in preparing the polymer A.

  The amount of the chain transfer agent may be appropriately set according to the composition of the monomer component, the polymerization conditions such as the polymerization temperature, the molecular weight of the target polymer, etc., and is not particularly limited, but the weight average molecular weight is several thousand to When obtaining tens of thousands of polymers, the amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass per 100 parts by mass of the monomer component.

  Examples of the polymerization method of the monomer component include a solution polymerization method, a bulk polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method, but the present invention is limited only to such examples. is not.

  When the monomer component is polymerized by a solution polymerization method, examples of the solvent include aromatic solvents such as toluene and xylene; alcohol solvents such as isopropyl alcohol and n-butyl alcohol; propylene glycol methyl ether and dipropylene glycol methyl. Ether solvents such as ether, ethyl cellosolve, butyl cellosolve; ester solvents such as ethyl acetate, butyl acetate, cellosolve acetate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diacetone alcohol; amide solvents such as dimethylformamide However, the present invention is not limited to such examples. These solvents may be used alone or in combination of two or more. The amount of the solvent may be appropriately determined in consideration of the polymerization conditions, the composition of the monomer components, the concentration of the resulting polymer, and the like.

  The polymerization of the monomer component can be performed by an ionic polymerization method such as a cationic polymerization method. Examples of the polymerization initiator used in the cationic polymerization include heteropoly acid, perchloric acid, sulfuric acid, phosphoric acid, p-toluenesulfonic acid, picrylsulfonic acid, trifluoromethanesulfonic acid, trichloroacetic acid, trifluoroacetic acid and the like. Protonic acid, boron trifluoride, aluminum bromide, aluminum chloride, antimony pentachloride, ferric chloride, tin tetrachloride, titanium tetrachloride, mercury chloride, zinc chloride and other Lewis acids, iodine, triphenylchloromethane, etc. Although mentioned, this invention is not limited only to this illustration.

  The heteropolyacid has, for example, a Keggin structure having an atom such as tungsten, molybdenum, or vanadium at the center of the acid, and the heteroatom is an atom such as phosphorus, silicon, germanium, titanium, zirconium, boron, arsenic, or cobalt. Polyacid. Examples of the heteropoly acid include phosphotungstic acid, silicotungstic acid, phosphomolybdic acid, silicomolybdic acid, borotungstic acid, boromolybdic acid, cobalt molybdic acid, cobalt tungstic acid, arsenic tungstic acid, germanium tungstic acid, and phosphororib. Examples include detungstic acid and boro-rib tungstic acid, but the present invention is not limited to such examples. Among these, phosphotungstic acid is preferable because it is uncolored, has high solubility in organic solvents, and is excellent in polymerization initiation ability.

  The amount of the polymerization initiator is preferably 1 ppm to 30% by mass, more preferably 5 ppm, based on the monomer component, from the viewpoint of allowing the polymerization reaction to be quickly performed and the polymerization reaction to be easily controlled. -20% by mass, more preferably 10 ppm to 10% by mass.

  The polymerization conditions for polymerizing the monomer components may be set as appropriate according to the polymerization method, and are not particularly limited. The polymerization temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that the polymerization reaction of a monomer component may be completed. Moreover, it is preferable that the atmosphere in superposition | polymerization is inert gas, such as nitrogen gas and argon gas, for example.

  After the monomer component is polymerized, the polymerization reaction may be stopped by adding a polymerization reaction terminator to the obtained reaction mixture, if necessary. Examples of the polymerization reaction terminator include organic bases such as amines such as ammonia and triethylamine, and inorganic bases such as sodium hydroxide and potassium hydroxide, but the present invention is not limited to such examples only. Absent.

  Polymer E is obtained by polymerizing the monomer components as described above. The lower limit of the weight average molecular weight of the polymer E is preferably 4000 or more, more preferably 5000 or more, further preferably 7000 or more, and the upper limit is preferably 1,000,000 or less, more preferably 600,000 or less, Preferably it is 400,000 or less. The weight average molecular weight is a value when measured by gel permeation chromatography (GPC) with a polystyrene standard.

  Further, the hydroxyl value of the polymer E (nonvolatile content) is preferably 0.4 to 200 mgKOH / g, more preferably 1 to 100 KOH / g, and still more preferably, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance. Is 3-60 mg KOH / g.

(F) Polymer F
As described above, the polymer F is obtained by reacting a polymer obtained by polymerizing a monomer component containing a monomer having an acid anhydride group with a monomer having a hydroxyl group. It is done.

  Examples of the monomer having an acid anhydride group include an unsaturated carboxylic acid anhydride and an aromatic carboxylic acid anhydride. These monomers having an acid anhydride group are each used alone. Two or more types may be used in combination.

  As the unsaturated carboxylic acid anhydride, examples of the monomer having an acid anhydride group include unsaturated carboxylic acid anhydrides such as maleic anhydride, butenyl succinic anhydride, tetrahydrophthalic anhydride, and citraconic anhydride. Although mentioned, this invention is not limited only to this illustration. These unsaturated carboxylic acid anhydrides may be used alone or in combination of two or more.

  Examples of the aromatic carboxylic acid anhydride include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, naphthalic anhydride, and the like, but the present invention is not limited to such examples. . These aromatic carboxylic acid anhydrides may be used alone or in combination of two or more.

  Among the monomers having an acid anhydride group, maleic anhydride and phthalic anhydride are preferable from the viewpoint of improving adhesion, weather resistance, and blocking resistance.

  The monomer component may contain other monomers as long as the object of the present invention is not impaired. Other monomers include, for example, a monomer having active hydrogen, an acidic phosphate ester monomer, a (meth) acrylic ester, a monomer having an epoxy group, a monomer having a nitrogen atom, Monomers having two or more polymerizable double bonds, aromatic monomers, monomers having a halogen atom, vinyl ester monomers, vinyl ether monomers, etc. may be mentioned. Is not limited to such examples. These monomers may be used alone or in combination of two or more. Examples of these monomers are the same as those exemplified above.

  Among the other monomers, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance, a monomer having active hydrogen, (meth) acrylic acid ester is preferable, alkyl (meth) acrylate and ( More preferred is cycloalkyl (meth) acrylate.

  In addition, from the viewpoint of improving weather resistance and blocking resistance, the other monomer may be a monomer having an ultraviolet absorbing group such as a benzotriazole monomer, a benzophenone monomer, or a triazine monomer. A monomer; a monomer having an ultraviolet-stable group may be included. Examples of the monomer having a UV-absorbing group and the monomer having a UV-stable group are the same as those used in preparing the polymer A.

  The monomer component may contain acrylic acid having a basic structure of bisarylfluorene from the viewpoint of improving hydrolysis resistance and insulation resistance. Examples of the acrylic acid having bisarylfluorene as a basic structure are the same as those used in preparing the polymer A.

  The content of the monomer having a carboxyl group or an acid anhydride group in the monomer component is preferably 0.5% by mass or more, more preferably 1% by mass or more, and still more preferably, from the viewpoint of improving adhesiveness. Is 3% by mass or more, particularly preferably 5% by mass or more, and the upper limit is 100% by mass.

  When polymerizing the monomer component, a chain transfer agent may be used as necessary from the viewpoint of suppressing an increase in molecular weight distribution and gelation. Examples of the chain transfer agent are the same as those used in preparing the polymer A.

  The amount of the chain transfer agent may be appropriately set according to the composition of the monomer component, the polymerization conditions such as the polymerization temperature, the molecular weight of the target polymer, etc., and is not particularly limited, but the weight average molecular weight is several thousand to When obtaining tens of thousands of polymers, the amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass per 100 parts by mass of the monomer component.

  Examples of the method for polymerizing the monomer component include a solution polymerization method, a bulk polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method, but the present invention is limited only to such examples. It is not a thing.

  Examples of the solvent used when the monomer component is polymerized by the solution polymerization method are the same as those used when the polymer A is prepared.

  A polymerization initiator can be used when the monomer component is polymerized. As a polymerization initiator, the same thing as used when preparing the said polymer A is illustrated. The amount of the polymerization initiator may be appropriately set according to the desired physical properties of the polymer to be obtained. Usually, it is preferably 0.05 to 30 parts by mass, more preferably 100 parts by mass of the monomer component. 0.15 to 10 parts by mass.

  The polymerization conditions for polymerizing the monomer components may be set as appropriate according to the polymerization method, and are not particularly limited. The polymerization temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that the polymerization reaction of a monomer component may be completed. Moreover, it is preferable that the atmosphere in superposition | polymerization is inert gas, such as nitrogen gas and argon gas, for example.

  Next, the polymer obtained by polymerizing the monomer component containing a monomer having a carboxyl group or an acid anhydride group as described above is reacted with a monomer having a hydroxyl group.

  Examples of the monomer having a hydroxyl group include carbons of alkyl groups such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, and hydroxybutyl methacrylate. 1 to 4 (meth) acrylic acid hydroxyalkyl; caprolactone-modified 2-hydroxyethyl acrylate, caprolactone-modified 2-hydroxyethyl methacrylate and other alkyl groups having 1 to 4 carbon atoms such as caprolactone-modified hydroxyalkyl (meth) acrylate Hydroxyl group-containing (meth) acrylic acid ester having 1 to 4 carbon atoms of alkyl group; methyl α-hydroxymethyl acrylate, methyl α-hydroxymethyl methacrylate, α-hydroxymethyl acrylic acid Chill, alpha-hydroxy number of carbon atoms in each alkyl group such as methyl ethyl methacrylate but like 1-4 alpha-hydroxyalkyl alkyl acrylate, the present invention is not limited only to those exemplified. These monomers having a hydroxyl group may be used alone or in combination of two or more. Caprolactone-modified hydroxy (meth) acrylate can be easily obtained commercially, for example, as trade name: Plaxel FM1, Plaxel FM1D, Plaxel FM2D, Plaxel FM3, Plaxel FA1DM, Plaxel FA2D manufactured by Daicel Chemical Industries, Ltd. it can.

  The reaction between the polymer and the monomer having a hydroxyl group can be performed, for example, by adding a monomer having a hydroxyl group to the reaction mixture from which the polymer is obtained.

  The reaction conditions for reacting the polymer with a monomer having a hydroxyl group may be appropriately set according to the reaction method, and are not particularly limited. The reaction temperature is preferably selected from the range of room temperature to 200 ° C, more preferably 40 to 140 ° C. What is necessary is just to set reaction time suitably so that reaction may be completed. The atmosphere during the reaction is not particularly limited and may be air, for example, an inert gas such as nitrogen gas or argon gas, or a mixed gas of oxygen and inert gas. There may be.

  By reacting the polymer with a monomer having a hydroxyl group as described above, the polymer F is obtained. The lower limit of the weight average molecular weight of the polymer F is preferably 4000 or more, more preferably 5000 or more, and further preferably 7000 or more. The upper limit is preferably 1,000,000 or less, more preferably 600,000 or less, Preferably it is 400,000 or less. The weight average molecular weight is a value when measured by gel permeation chromatography (GPC) with a polystyrene standard.

  The acid value or hydroxyl value of the polymer F (nonvolatile content) is preferably 0.1 to 200 mgKOH / g, more preferably 1 to 100 mgKOH / g, from the viewpoint of improving adhesiveness, weather resistance and blocking resistance. More preferably, it is 3-60 mgKOH / g.

The hydroxyl value of the unsaturated double bond-containing polymer means the amount (mg) of potassium hydroxide corresponding to the hydroxyl group contained in 1 g of the thermally decomposable polymer, and the unsaturated double bond-containing polymer. This is the amount (mg) of potassium hydroxide (KOH) required to acetylate the hydroxyl group contained in 1 g. The hydroxyl value of the unsaturated double bond-containing polymer is, for example, a thermally decomposable polymer prepared by polymerizing a monomer component containing 1% by mass of 2-hydroxyethyl methacrylate as a hydroxyl group-containing monomer. Taking an example, the hydroxyl value of the unsaturated double bond-containing polymer has the formula:
[Hydroxyl value of unsaturated double bond-containing polymer]
= [0.01 / 130 (molecular weight of 2-hydroxyethyl methacrylate)] x 56100 = 4.3 mgKOH / g
Can be determined based on

  In the present invention, the content of the ethylenically unsaturated double bond present at the end of the side chain per molecule of the unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain is From the viewpoint of improving the property, weather resistance and blocking resistance, 0.1 mol% or more is preferable, 1 mol% or more is more preferable, and 2.5 mol% or more is more preferable. The upper limit of the content of the ethylenically unsaturated double bond at the end of the side chain of the polymer is not particularly limited, but is usually 30 mol% or less.

  In the present invention, the molecular weight distribution (weight average molecular weight / number average molecular weight) of an unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain is only in the environment actually used as a solar cell. In addition, even when accelerated tests are conducted in a high-temperature and high-humidity atmosphere, which is considered when evaluating solar cell modules, it has excellent adhesion and weather resistance to fillers used in solar cells, and electrical output characteristics. From the viewpoint of obtaining a solar cell module backsheet having a good appearance, it is 1.5 or more, preferably 1.8 or more, more preferably 2.0 or more, and is actually used as a solar cell. Not only in the environment where the solar cell module is evaluated, but also in a high-temperature and high-humidity atmosphere that is considered when evaluating solar cell modules. From the viewpoint of obtaining a back sheet for a solar cell module having excellent adhesion and weather resistance to the resulting filler, maintaining electrical output characteristics, and having a good appearance, preferably 6.0 or less, more preferably 5.5 or less. Is 5.0 or less.

  For example, when the glass transition temperature of an unsaturated double bond-containing polymer (non-volatile component) having an ethylenically unsaturated double bond at the end of the side chain is less than 100 ° C., the ethylenically unsaturated group is present at the end of the side chain. From the viewpoint of improving the weather resistance, the weight average molecular weight of the unsaturated double bond-containing polymer having a saturated double bond is preferably 4000 or more, more preferably 5000 or more, and even more preferably 7000 or more. From the viewpoint of improving, it is preferably 1,000,000 or less, more preferably 600,000, still more preferably 400,000 or less, and still more preferably 60,000 or less. In this case, the glass transition temperature of the unsaturated double bond-containing polymer (nonvolatile component) having an ethylenically unsaturated double bond at the end of the side chain is preferably −30 ° C. or higher from the viewpoint of improving the weather resistance. More preferably, it is −15 ° C. or higher, more preferably −5 ° C. or higher, and preferably 98 ° C. or lower, more preferably 90 ° C. or lower, from the viewpoint of improving the adhesive strength.

  For example, when the glass transition temperature of an unsaturated double bond-containing polymer (nonvolatile component) having an ethylenically unsaturated double bond at the end of the side chain is 100 ° C. or higher, the ethylenically unsaturated group is present at the end of the side chain. The weight average molecular weight of the unsaturated double bond-containing polymer having a saturated double bond is not only determined in the environment where it is actually used as a solar cell, but also in a high-temperature and high-humidity atmosphere considered when evaluating solar cell modules. Even when an accelerated test is performed, it is preferably 4000 or more, more preferably 5000 or more, and even more preferably 7000 or more, from the viewpoint of improving the adhesiveness to the filler used in the solar cell, thereby improving the adhesive force. From the viewpoint of achieving the above, it is preferably 1,000,000 or less, more preferably 600,000 or less, further preferably 400,000 or less, and still more preferably 60,000 or less. In this case, the glass transition temperature of the unsaturated double bond-containing polymer (nonvolatile component) having an ethylenically unsaturated double bond at the end of the side chain is preferably 105 ° C. or higher from the viewpoint of improving blocking properties. Preferably it is 110 degreeC or more, From a viewpoint of improving adhesive force, Preferably it is 130 degrees C or less, More preferably, it is 125 degrees C or less, More preferably, it is 120 degrees C or less.

In the present invention, the glass transition temperature of the unsaturated double bond-containing polymer (nonvolatile content) is the single component contained in the monomer component used as the raw material of the unsaturated double bond-containing polymer (nonvolatile content). From the glass transition temperature (Tg) (absolute temperature: K) of the homopolymer consisting of the monomer and the mass fraction of the monomer, the formula (I):
1 / Tg = W ₁ / Tg ₁ + W ₂ / Tg ₂ + W ₃ / Tg ₃ +... + W _n / Tg _n (I)
[Wherein Tg is the glass transition temperature (K) of the thermally decomposable polymer to be obtained, W ₁ , W ₂ , W ₃ ... W _n is the mass fraction of each monomer, _{Tg 1, Tg 2, Tg 3} ···· Tg n are respectively the glass transition temperature (K) of a homopolymer composed of a monomer corresponding to the mass fraction of each monomer]
It can obtain | require based on the Formula of Fox (Fox) represented by these. The glass transition temperature of the thermally decomposable polymer (nonvolatile component) can also be measured by DSC (differential scanning calorimeter), DTA (differential thermal analyzer), and TMA (thermomechanical analyzer).

  Among the methods for measuring the glass transition temperature of these unsaturated double bond-containing polymers (nonvolatile content), from the viewpoint of convenience of resin design, the glass transition temperature of the thermally decomposable polymer (nonvolatile content) is mainly The glass transition temperature determined based on the formula (I) is used.

  In the following examples and the like, the glass transition temperature of the unsaturated double bond-containing polymer (nonvolatile content) is the mass fraction of each monomer in all the monomer components used in the polymerization and this. The glass transition temperature calculated | required from the glass transition temperature of the homopolymer of the monomer corresponding to is meant.

  For monomers with unknown glass transition temperature, such as special monomers and polyfunctional monomers, the total content of monomers with unknown glass transition temperature in the monomer component is 10%. If it is less than or equal to%, the glass transition temperature can be determined using only monomers whose glass transition temperature is known. In addition, when the total content of monomers with unknown glass transition temperature in the monomer component exceeds 10% by mass, the glass transition of the thermally decomposable polymer obtained by polymerizing the monomer component It is determined by measuring the temperature by differential scanning calorimetry (DSC), differential calorimetry (DTA), thermomechanical analysis (TMA) or the like.

  For example, Kyozo Kitaoka, “Introduction to Synthetic Resins for Paints”, First Edition, Kobunshi Publishing Co., Ltd., May 1974; edited by the Society of Polymer Science, “Polymer Data Handbook” (Basics) ”, first edition, Bafukan Co., Ltd., January 1986;“ Functional Chemicals Catalog ”, Kyoeisha Chemical Co., Ltd., October 2004, and the like. The glass transition temperature of the homopolymer is, for example, 130 ° C. for a homopolymer of methacrylic acid, 55 ° C. for a homopolymer of 2-hydroxyethyl methacrylate, 18 ° C. for a homopolymer of dimethylaminoethyl methacrylate, and n-butyl methacrylate. 20 ° C. for homopolymer of cyclohexyl methacrylate, 83 ° C. for homopolymer of cyclohexyl methacrylate, 180 ° C. for homopolymer of isobornyl methacrylate, 60 ° C. for homopolymer of tetrahydrofurfuryl methacrylate, homopolymer of 2-ethylhexyl acrylate Then, it is -70 degreeC.

  As described above, the adhesive for backsheet of the present invention contains an unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain. The content of the unsaturated double bond-containing polymer (nonvolatile component) having an ethylenically unsaturated double bond at the end of the side chain in the backsheet adhesive is preferably from the viewpoint of improving adhesiveness and weather resistance. It is 5-80 mass%, More preferably, it is 5-60 mass%. The content of the unsaturated double bond-containing polymer (nonvolatile content) in the backsheet adhesive can be adjusted by adjusting the amount of the organic solvent contained in the backsheet adhesive. Examples of the organic solvent include organic solvents used when preparing the polymer A, but the present invention is not limited by the type of the organic solvent.

  Note that the non-volatile content of the adhesive for the backsheet may be composed only of an unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain, but this hinders the object of the present invention. If it is in the range which does not carry out, the other polymer may be contained.

  The adhesive for backsheet of the present invention may contain a curing agent from the viewpoint of improving hydrolysis resistance and insulation resistance.

  Examples of the curing agent include (block) polyisocyanate compounds, epoxy resins, oxazoline group-containing resins, aminoplast resins, and the like, but the present invention is not limited to such examples. These curing agents may be used alone or in combination of two or more. Among the curing agents, at least one monomer selected from the group consisting of a (block) polyisocyanate compound, an epoxy resin, and an oxazoline group-containing resin is preferable from the viewpoint of curability and weather resistance. ) Polyisocyanate compounds are more preferred.

  The (block) polyisocyanate compound means a polyisocyanate compound and / or a block polyisocyanate compound.

  Examples of the polyisocyanate compound include compounds having at least two isocyanate groups in the molecule. Specific examples of the polyisocyanate compound include tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), lysine diisocyanate, trimethylhexamethylene diisocyanate, Polyisocyanates such as 1,3-bis (isocyanatomethyl) cyclohexane, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate; modified polyisocyanates such as adducts, burettes and isocyanurates of these polyisocyanates (Derivatives) and the like can be mentioned, but the present invention is not limited to such examples.

  The block polyisocyanate compound crosslinks the adhesive by heating, but has properties and adhesiveness that improve storage stability at room temperature. In addition, the block polyisocyanate compound is not only used in an environment actually used as a solar cell, but also in a case where an accelerated test is performed in a high-temperature and high-humidity atmosphere studied when evaluating a solar cell module. It is further excellent in adhesion to the filler used in the battery. The block polyisocyanate compound is usually one in which the isocyanate group of the polyisocyanate compound is blocked with a blocking agent. Examples of the blocking agent include ε-caprolactam, phenol, cresol, oxime, alcohol, and the like, but the present invention is not limited to such examples. Among the block polyisocyanate compounds, a non-yellowing polyisocyanate compound having no isocyanate group directly bonded to an aromatic ring is preferable from the viewpoint of preventing yellowing of the adhesive layer.

  (Block) Polyisocyanate compounds are, for example, manufactured by Sumika Bayer Urethane Co., Ltd., trade names: Death Module N3200, Death Module N3300, Death Module BL3175, Death Module N3400, Death Module N3600, Death Module VPLS2102, Sumidur BL3575MPA / X: Asahi Kasei Chemicals Co., Ltd., trade name: Duranate E-402-90T, Duranate E-405-80T, Duranate TPA-B80E, Duranate SBN-70D, Duranate MF-B60X, Duranate MF-K60X, etc. It can be easily obtained.

  The amount of the (block) polyisocyanate compound is not particularly limited. For example, the amount of isocyanate groups in the (block) polyisocyanate compound per mole of hydroxyl groups in the unsaturated double bond-containing polymer is preferably from the viewpoint of improving the hydrolysis resistance and insulation resistance of the adhesive layer. 0.6 mol or more, more preferably 0.8 mol or more, and prevents the adhesive layer from foaming due to the reaction of unreacted isocyanate groups with moisture in the air and also prevents whitening. Therefore, the amount is preferably 10 mol or less, more preferably 8 mol or less.

  Examples of the epoxy resin include Japan Epoxy Resin Co., Ltd., trade names: Epicoat 828, Epicoat 1001X70, Epicoat 815; Asahi Denka Kogyo Co., Ltd., trade name: Adeka Resin EP-4100. Is not limited to such examples.

  Examples of the oxazoline group-containing resin include those manufactured by Nippon Shokubai Co., Ltd., trade names: Epocross K-2000 series, Epocross WS-500, Epocross WS-700, etc., but the present invention is limited to such examples. It is not something.

  An aminoplast resin is an addition condensate of a compound having an amino group such as melamine or guanamine with formaldehyde, and is also called an amino resin.

  Examples of aminoplast resins include dimethylol melamine, trimethylol melamine, tetramethylol melamine, pentamethylol melamine, hexamethylol melamine, fully alkyl methylated melamine, fully alkyl butylated melamine, fully alkyl isobutylated melamine, completely Melamine resins such as alkyl mixed etherified melamine, methylol group methylated melamine, imino group methylated melamine, methylol group mixed etherified melamine, imino group mixed etherified melamine; butylated benzoguanamine, methyl / ethyl mixed alkyl Benzoguanamine, methyl / butyl mixed alkylated benzoguanamine, guanamine resins such as butylated glycoluril, and the like, but the present invention is limited only to such examples. Not to.

  Aminoplast resins are commercially available, for example, as Mitsui Cytec Co., Ltd., trade names: Cymel 1128, Cymel 303, My Coat 506, Cymel 232, Cymel 235, Cymel 771, Cymel 325, Cymel 272, Cymel 254, Cymel 1170, and the like. Can be easily obtained.

  The amount of aminoplast resin is not particularly limited. The mass ratio of the solid content of the unsaturated double bond-containing polymer and the aminoplast resin (unsaturated double bond-containing polymer / aminoplast resin) is preferably 6/4 or more from the viewpoint of improving adhesiveness. From the viewpoint of improving the hydrolysis resistance and adhesion of the adhesive layer, it is preferably 9/1 or less.

  Since the amount of the curing agent varies depending on the type of the curing agent and the like, it cannot be determined unconditionally. However, normally, 100 mass of an unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain. From the viewpoint of hydrolysis resistance and insulation resistance of the adhesive layer per part, preferably 1 part by mass or more, more preferably 3 parts by mass or more, and from the viewpoint of improving adhesiveness, preferably 60 parts by mass or less. More preferably, it is 50 mass parts or less, More preferably, it is 30 mass parts or less.

  The adhesive for backsheets of the present invention can be cured under various curing conditions depending on the application and the type of curing agent used in the adhesive for backsheet. The backsheet adhesive of the present invention can be used as a room temperature curing type, a heat curing type, an ultraviolet curing type, or an electron beam curing type. Moreover, there is no limitation in particular in the quantity of a hardening | curing agent, its addition method, a dispersion method, etc. For example, in the case where an unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain has a plurality of hydroxyl groups in one molecule, depending on the unsaturated double bond-containing polymer The amount of the curing agent may be adjusted, or an addition method, a dispersion method, etc. may be selected.

  In the backsheet adhesive of the present invention, if necessary, for promoting the crosslinking reaction between the unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain and the curing agent. A curing catalyst may be included. Although there is no limitation in particular as a curing catalyst, For example, when using a (block) polyisocyanate compound, dibutyltin dilaurate, a tertiary amine, etc. are preferable. Further, when an aminoplast resin is used, an acidic or basic curing catalyst is preferable.

  Moreover, you may contain an additive etc. in the adhesive agent for backsheets of this invention. Examples of the additive include additives generally used in resin compositions that form films and coating films. Specific examples of additives include leveling agents; inorganic fine particles such as colloidal silica and alumina sol; organic fine particles such as polymethyl methacrylate; antifoaming agents; anti-sagging agents; silane coupling agents; titanium white, composite oxides Pigments such as pigments, carbon black, organic pigments, and pigment intermediates; pigment dispersants; antioxidants such as phosphorus antioxidants and phenolic antioxidants; viscosity modifiers; UV stabilizers; metal deactivators; Peroxide decomposer; Flame retardant; Reinforcing agent; Plasticizer; Lubricant; Rust preventive agent; Fluorescent brightener; Organic and inorganic UV absorbers; Inorganic heat absorber; Organic and inorganic Examples include flame retardants; organic and inorganic antistatic agents; and dehydrating agents such as methyl orthoformate, but the present invention is not limited to such examples.

  Note that the amounts of the curing catalyst, the solvent, and the additive vary depending on the type of the curing catalyst, and cannot be determined unconditionally. Therefore, it is preferable to appropriately adjust according to the properties required for the adhesive layer.

  In the present invention, from the viewpoint of improving adhesiveness, examples of the backsheet adhesive include polyester resins, modified polyolefin resins, ethylene-vinyl acetate copolymer (EVA), polyvinyl butyral (PVB), and silicone resins. Further, a thermoplastic resin such as vinyl chloride resin, polyurethane, and amino group-containing resin, and a tackifier may be contained.

  Examples of the tackifier include rosin tackifiers; rosin ester tackifiers, terpene tackifiers, terpene phenol tackifiers, saturated hydrocarbon resins, coumarone tackifiers, Coumarone indene tackifier, styrene resin tackifier, xylene resin tackifier, phenol resin tackifier, petroleum resin tackifier, etc. Each agent may be used alone or in combination of two or more.

  The amount of tackifier may be appropriately adjusted according to the desired tackiness, and is not particularly limited, but from the viewpoint of improving the tackiness to the adherend per 100 parts by mass of the unsaturated double bond-containing polymer. The amount is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, and preferably 200 parts by mass or less, more preferably 150 parts by mass or less, from the viewpoint of suppressing a decrease in adhesive strength.

  Examples of the adherend to which the adhesive for backsheet of the present invention can be applied include, for example, an adherend comprising a polymer obtained by polymerizing a monomer component containing a carboxylic acid vinyl ester, polyester An adherend composed of polycarbonate, an adherend composed of polycarbonate, an adherend composed of fluororesin, an adherend composed of (meth) acrylic resin, and the like are included, but the present invention is limited only to such examples. is not. Among these adherends, polyester base materials and fluororesin base materials are preferable from the viewpoint of weather resistance and cost.

  The adhesive for back sheets of this invention has the advantage that it can be used conveniently for the to-be-adhered body which consists of a polymer obtained by polymerizing the monomer component containing carboxylic acid vinyl ester. Examples of the vinyl carboxylate include vinyl acetate, vinyl monochloroacetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprylate, vinyl caprate, vinyl laurate, vinyl myristate, vinyl palmitate, and vinyl stearate. Saturated aliphatic carboxylic acid vinyl esters which may have a substituent such as halogen atoms such as vinyl pivalate and vinyl octylate; alicyclic carboxylic acid vinyl esters such as cyclohexyl vinyl carboxylate; divinyl adipate; Examples thereof include unsaturated aliphatic carboxylic acid vinyl esters such as (meth) vinyl acrylate, vinyl crotonate, and vinyl sorbate; and aromatic carboxylic acid vinyl esters such as vinyl benzoate and vinyl cinnamate. Limited to illustration only Not intended to be.

  When the adhesive for backsheet of the present invention is used for an adherend comprising a polymer obtained by polymerizing a monomer component containing a vinyl carboxylate, the adhesive for backsheet of the present invention is used. There is an advantage that the agent and the adherend can be firmly bonded. The reason why the adhesive for backsheet of the present invention and the adherend can be firmly bonded is not clear, but is probably the side chain contained in the adhesive for backsheet of the present invention. Based on the fact that the unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the terminal is cleaved to form a chemical bond with the ester group of the adherend. Conceivable.

  Further, in the present invention, in addition to the above-mentioned adherend, in view of heat resistance, strength physical properties, electrical insulation, hydrolysis resistance, etc., polyolefin resin, polyamide resin, polyarylate resin, etc. An adherend made of a resin can be used.

  Examples of the form of the adherend include a molded body formed into a predetermined shape including a film, a plate, and the like, but the present invention is not limited to such an example. A suitable adherend in the present invention includes a film made of a resin containing an ethylene-vinyl acetate copolymer.

  Applications of adherends include, for example, solar cell encapsulants, agricultural resin films, construction civil engineering resin sheets, automotive exterior parts, food packaging paper, laminated materials with a paper-coated resin surface, artificial grass The present invention is not limited only to such illustrations.

  In addition, by applying the backsheet adhesive of the present invention to a backsheet used for a solar cell module, a backsheet for a solar cell module in which an adhesive layer made of the backsheet adhesive is formed is manufactured. Can do. In the back sheet for a solar cell module on which the adhesive layer is formed, the surface on which the adhesive layer is formed is a surface to be bonded to the filler constituting the solar cell module. As a back sheet, what is normally used for a solar cell should just be used, and this invention is not limited by the kind of the said back sheet.

  Examples of the filler include ethylene-vinyl acetate copolymer (EVA), polyvinyl butyral, silicone resin, vinyl chloride resin, polyurethane, and the like, but the present invention is not limited to such examples. Among these, an ethylene-vinyl acetate copolymer (EVA) is preferable from the viewpoint of weather resistance and flame retardancy and from the viewpoint of increasing the adhesive strength. The thickness after drying of the adhesive layer made of the adhesive for backsheet of the present invention formed on the surface to be bonded to the filler constituting the solar cell module is preferably 0 from the viewpoint of adhesion and weather resistance. .1 μm or more, more preferably 0.3 μm or more, further preferably 1 μm or more, and from the viewpoint of embrittlement prevention, preferably 100 μm or less, more preferably 50 μm or less, still more preferably 30 μm or less, and even more preferably 10 μm or less. It is.

  FIG. 1 is a schematic cross-sectional view showing the configuration of a back sheet for a solar cell module in which the substrate is bonded with an adhesive. FIG. 1 has the simplest structure of a solar cell module backsheet. The two base materials 1 and 1 are bonded together with an adhesive 2. The base materials 1 and 1 may be base materials made of the same material, or may be base materials made of different materials.

  Examples of the adhesive 2 include an adhesive for a back sheet of the present invention, an adhesive for a back sheet other than the adhesive for a back sheet of the present invention, a polyester adhesive, a polyurethane adhesive, a polycarbonate adhesive, and the like. However, the present invention is not limited to such examples. The adhesive 2 is preferably the backsheet adhesive of the present invention from the viewpoints of adhesiveness and weather resistance. An adhesive layer 4 made of the adhesive for backsheet of the present invention is formed on one surface of the two substrates 1 and 1.

  The adhesive for backsheets of the present invention is not only the environment actually used as a solar cell, but also when performing an accelerated test in a high-temperature and high-humidity atmosphere that is considered when evaluating solar cell modules. It exhibits excellent effects such as excellent adhesion and weather resistance to fillers used in solar cells, maintaining electrical output characteristics, and making it difficult to cause poor appearance of the backsheet.

  FIG. 2 is a schematic cross-sectional view showing another embodiment when the barrier layer 3 is interposed in the solar cell module backsheet. In FIG. 2, adhesives 2 and 2 are applied to one surface of each of the two substrates 1 and 1, and an adhesive layer formed by the adhesives 2 and 2 on the two substrates 1 and 1 The two base materials 1 and 1 are integrated with a barrier layer 3 such as a gas barrier layer interposed therebetween, and the backsheet adhesive of the present invention is bonded to the surface to be bonded to the filler constituting the solar cell module. An adhesive layer 4 made of an agent is formed. Also in the solar cell module backsheet of this embodiment, since the adhesive layer 4 made of the backsheet adhesive of the present invention is formed, not only the environment actually used as a solar cell, but also the solar cell module. Even when an accelerated test is conducted in a high-temperature and high-humidity atmosphere, which is considered when evaluating the back sheet, it has excellent adhesion and weather resistance to fillers used in solar cells, maintains electrical output characteristics, and back sheet An excellent effect that it is difficult to cause poor appearance is exhibited.

  Among the back sheet shown in FIG. 1 and the back sheet shown in FIG. 2, the back sheet shown in FIG. 1 is preferable from the viewpoint of cost reduction.

  Examples of the gas barrier layer 3 shown in FIG. 2 include a vapor deposition substrate on which an oxide such as a metal foil, a metal vapor deposition film, and an oxide vapor deposition film is vapor-deposited.

  Examples of the metal foil include an aluminum foil. As a metal vapor deposition film, metal vapor deposition films, such as an aluminum vapor deposition film which vapor-deposited metals, such as aluminum, to a polyester film and a polyolefin-type stretched film, for example are mentioned.

  Examples of the oxide vapor-deposited film include a film obtained by vapor-depositing aluminum oxide, silicon dioxide, tin oxide, magnesium oxide, indium oxide, and complex oxides thereof on a polyester film, and is transparent and has a gas barrier such as oxygen and water vapor. The thing which has property etc. are mentioned. In these, the film which vapor-deposited silicon dioxide on the polyester film and the film which vapor-deposited aluminum oxide on the polyester film are preferable.

  In the oxide vapor deposition film, the thickness of a suitable oxide vapor deposition layer varies depending on the type and composition of the oxide, but in general, from the viewpoint of forming a uniform oxide vapor deposition layer, preferably 5 nm or more, more preferably Is 10 nm or more, and is preferably 300 nm or less, more preferably 150 nm or less, from the viewpoint of imparting flexibility and preventing cracks from being generated by external stress.

  Examples of the method for forming an oxide deposition layer include a vacuum deposition method, a thin film formation method such as a sputtering method, an ion plating method, and a plasma vapor deposition method (CVD). However, the present invention is not limited to such examples.

  Before applying the backsheet adhesive of the present invention to the adherend, from the viewpoint of improving the adhesive strength between the backsheet adhesive of the present invention and the adherend, organic peroxide is applied to the surface of the adherend. It is preferable to apply an object, to include the organic peroxide in the adhesive for backsheet of the present invention, or to previously include the organic peroxide in the adherend. In particular, when an adherend composed of a polymer obtained by polymerizing a monomer component containing a carboxylic acid vinyl ester is used as the adherend, an organic peroxide is formed on the surface of the adherend. The adhesive strength between the backsheet adhesive of the present invention and the adherend can be improved by applying the above-described organic peroxide or including the organic peroxide in the backsheet adhesive of the present invention.

  Examples of the organic peroxide include diacyl peroxides such as dibenzoyl peroxide, diisobutyl peroxide, ditrimethoxyhexanoyl peroxide, dilauroyl peroxide, disuccinic acid peroxide, di (methylbenzoyl) peroxide, and diisononyl peroxide. Oxides; ketone peroxides such as methyl ethyl ketone peroxide, cyclohexane peroxide, acetylacetone peroxide; tert-butylperoxyneodecanoate, tert-butylperoxybenzoate, tert-butylperoxyneoheptanoate, tert-butylperoxide Oxypivalate, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxyisobutyrate, te t-butylperoxyacetate, tert-butylperoxyisononanoate, tert-hexylperoxypivalate, tert-hexylperoxy-2-ethylhexanoate, tert-hexylperoxyisopropylmonocarbonate, tetramethylbutyl Alkyl peroxyesters such as peroxyethylhexanoate and 2,5-dimethyl-2,5-di (ethylhexanoylperoxy) hexanoate; di-n-propylperoxycarbonate, tert-butylperoxy-2-ethylhexyl Carbonate, diisopropylperoxycarbonate, di (4-tert-butylcyclohexyl) peroxycarbonate, di (2-ethylhexyl) peroxydicarbonate, disec-butylperoxydi -Bonate, tert-butylperoxy-2-ethylhexyl carbonate, tert-butylperoxyisopropyl carbonate, 1,6-bis (tert-butylperoxycarboxy) hexane, bis (4-tert-butylcyclohexyl) peroxydicarbonate, Peroxycarbonates such as tert-amylperoxy-2-ethylhexyl carbonate, di (sec-butyl) peroxydicarbonate; dicumyl peroxide, tert-butylperoxy-2-ethylhexyl carbonate, di (isopropyl) peroxycarbonate , Di (4-tert-butylcyclohexyl) peroxycarbonate, di (2-ethylhexyl) peroxydicarbonate, di (sec-butyl) peroxydicar Tert-butylperoxy-2-ethylhexyl carbonate, tert-butylperoxyisopropyl carbonate, 1,6-bis (tert-butylperoxycarboxy) hexane, bis (4-tert-butylcyclohexyl) peroxydicarbonate, Although dialkyl peroxides, such as tert-amyl peroxy-2-ethylhexyl carbonate, are mentioned, this invention is not limited only to this illustration. These organic peroxides may be used alone or in combination of two or more.

When applying the organic peroxide to the surface of the adherend, if necessary, the organic peroxide may be dissolved in an organic solvent to a desired concentration, and the resulting solution may be applied to the adherend. . The coating amount (solid content) of the organic peroxide on the adherend cannot be unconditionally determined because it varies depending on the type of the organic peroxide, but is usually about 0.01 to 1 g / m ^2. It is preferable that When the organic peroxide is contained in the backsheet adhesive of the present invention, the organic peroxide content in the backsheet adhesive of the present invention varies depending on the type of the organic peroxide, etc. However, it is usually preferably about 0.01 to 10% by mass.

  Further, from the viewpoint of stabilizing and improving the gas barrier property of the adhesive for backsheet of the present invention, for example, an undercoat layer composed of an acrylic polyol, an isocyanate compound and a silane compound may be provided on the adherend, An overcoat layer composed of a portion of polyvinyl alcohol or a completely saponified product and a silane compound may be provided on the deposited layer of the product.

  The back sheet adhesive of the present invention is applied on the adherend by a method such as gravure coating, roll coating, bar coating, reverse coating, etc. so that the film thickness after drying is 0.1 to 20 μm. Then, after bonding another substrate on the substrate by a method such as dry lamination, an adhesive layer made of an adhesive for the back sheet is formed on the surface to be bonded to the filler constituting the solar cell module. Thus, a solar cell module can be manufactured. At this time, the substrate may be subjected to a surface treatment for improving adhesiveness such as corona treatment, flame treatment, and plasma treatment, if necessary. For example, when a base material made of a fluororesin is used as the base material, it is preferable to perform plasma treatment or the like on the base material.

  The solar cell module in which the adhesive for backsheet of the present invention is used is not only an environment actually used as a solar cell, but also an accelerated test in a high-temperature and high-humidity atmosphere that is considered when evaluating the solar cell module. Even when it is carried out, it has excellent adhesion and weather resistance to the filler used in the solar cell, maintains electric output characteristics, and has an excellent effect that it is difficult to cause poor appearance of the backsheet.

  The solar cell module using the backsheet adhesive of the present invention can be easily configured, for example, by replacing the backsheet adhesive of the present invention as a backsheet in a commonly used solar cell module. it can. Moreover, the solar cell of this invention can be easily comprised by replacing a solar cell module with the solar cell module of this invention in the solar cell generally used, for example.

  Therefore, the adhesive for backsheets of this invention can be used conveniently as an adhesive for solar cell modules for bonding together the backsheet and filler used for the module for solar cells. The back sheet in which the adhesive layer made of the back sheet adhesive of the present invention is formed on the surface to be bonded to the filler constituting the solar cell module can be suitably used as the back sheet for the solar cell module. . The solar cell module having this solar cell module backsheet can be suitably used for solar cells.

  EXAMPLES Next, although this invention is demonstrated further in detail based on an Example, this invention is not limited only to this Example.

The following were used as the substrate or filler.
<Base material 1>
Teijin DuPont Films Co., Ltd., trade name: Tetron U298W [white polyethylene terephthalate (hereinafter referred to as PET) film]
<Substrate 2>
Product name: Tech Barrier (silicon dioxide vapor-deposited PET film), manufactured by Mitsubishi Plastics, Inc.
<Base material 3>
Product name: Lumirror X10S (heat-resistant oligomer PET film), manufactured by Toray Industries, Inc.
<Filler>
Product name: Fast cure, product number: RC02B (EVA sheet having a thickness of 400 μm), manufactured by Mitsui Chemicals Fabro Co., Ltd.

Production Example 1
In a 500 milliliter flask equipped with a stirrer, a dripping port, a thermometer, a cooling tube and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, 2.3 g of 2-hydroxyethyl methacrylate, 5.0 g of methyl methacrylate, 40.0 g of butyl acrylate, 23.8 g of cyclohexyl methacrylate, 2- (2-vinyloxyethoxy) ethyl acrylate [manufactured by Nippon Shokubai Co., Ltd.] , Product number: VEEA] 4.0 g, butyl methacrylate 24.9 g and a mixture of 2,2′-azobis (2,4-dimethylvaleronitrile) 9.8 g as a polymerization initiator was added dropwise over 3 hours, and after completion of the dropwise addition Then, by further heating for 2 hours, the unsaturated double bond-containing polymer solution (hereinafter referred to as “non-volatile content” of the unsaturated double bond-containing polymer having an allyl group at the end of the side chain is 49.9% by mass) Polymer 1 solution) was obtained. The obtained unsaturated double bond-containing polymer (hereinafter referred to as polymer 1) has a hydroxyl value of 10 mgKOH / g, a weight average molecular weight of 8,000, a molecular weight distribution of 2.2, and a glass transition temperature of The temperature was 0 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 1 was 3.0 mol%.

  In the following Examples and Comparative Examples, the weight average molecular weight, molecular weight distribution, and content of side chains having carbon-carbon double bonds of the unsaturated double bond-containing polymers were measured based on the following methods. .

(Weight average molecular weight)
The weight average molecular weight and molecular weight distribution of the polymer are values measured by gel permeation chromatography (GPC) with polystyrene standards. More specifically, the weight average molecular weight and the number average molecular weight of the polymer are determined by gel permeation chromatography [manufactured by Tosoh Corporation, product number: HLC-8320GPC, column: TSKgel Super Multipore HZ-M. The molecular weight distribution was determined by dividing the weight average molecular weight of the polymer by the number average molecular weight of the polymer.

[Content of side chain having carbon-carbon double bond]
The polymer (solution state) is added to excess hexane, re-precipitation is performed, and the generated precipitate is taken out and dried at a temperature of 40 ° C. under a reduced pressure of 1.33 hPa for 12 hours to remove volatile components. A powder sample was obtained.

Next, 30 mg of the powder sample obtained above was dissolved in 1 g of deuterated chloroform, and ¹ H of the polymer was obtained with a nuclear magnetic resonance apparatus (manufactured by Varian, model name: Unity plus 400, 400 Hz) using the obtained solution. -NMR was measured, and the content of the side chain having a carbon-carbon double bond was determined based on the intensity ratio between the protons of the vinyl group around 5.5 ppm and around 6.0 ppm and the other protons.

Production Example 2
Into a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas introduction port, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to about 80 ° C. while stirring. . In this flask, caprolactone-modified hydroxy methacrylate [Daicel Chemical Industries, Ltd., trade name: Plaxel FM1] 8.7 g, methyl methacrylate 10.0 g, cyclohexyl methacrylate 23.0 g, glycidyl methacrylate 10.0 g, butyl methacrylate 47.3 g 2,2,6,6-hexamethyl-4-piperidyl methacrylate [manufactured by ADEKA, trade name: ADK STAB LA87] 1.0 g and 2,2′-azobis (2,4-dimethylvaleronitrile as a polymerization initiator) ) After dropping a mixture of 0.6 g into the flask over 3 hours, the mixture was further heated for 2 hours to prepare a polymer solution. The solid content of the polymer contained in the obtained polymer solution was 50.0% by mass, and the weight average molecular weight of the polymer was 39000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 5.1 g of acrylic acid, 0.7 g of zinc octenoate as an esterification catalyst, and 4-hydroxy-2 as a polymerization inhibitor. A mixture of 0.01 g of 2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having a non-volatile content of 49.9% by mass of the unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain ( Hereinafter, the polymer 2 solution) was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 2) has a hydroxyl value of 20 mg KOH / g, a weight average molecular weight of 40,000, a molecular weight distribution of 4.0, and a glass transition temperature of The content of the side chain having a carbon-carbon double bond in the polymer 2 was 10.4 mol%.

Production Example 3
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, 1.2 g of 2-hydroxyethyl methacrylate, 40.0 g of methyl methacrylate, 3.6 g of cyclohexyl methacrylate, 4.0 g of acrylic acid, 51.2 g of butyl methacrylate and 2,2′-azobis ( A mixture of 1.8 g of 2,4-dimethylvaleronitrile) was continuously dropped into the flask over 3 hours, and then heated for another 2 hours to prepare a polymer solution. The solid content of the polymer contained in the obtained polymer solution was 50.1% by mass, and the weight average molecular weight of the polymer was 29000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 7.9 g of glycidyl methacrylate, 0.7 g of zinc octenoate as an esterification catalyst, and 4-hydroxy-2 as a polymerization inhibitor. A mixture of 0.01 g of 2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After the completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having an unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain is 50.0% by mass ( Hereinafter, the polymer 3 solution) was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 3) has a hydroxyl value of 5 mg KOH / g, a weight average molecular weight of 30000, a molecular weight distribution of 2.1, and a glass transition temperature of It was 55 ° C., and the content of side chains having a carbon-carbon double bond in Polymer 3 was 6.6 mol%.

Production Example 4
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In the flask, 18.0 g of 2-hydroxyethyl methacrylate, caprolactone-modified hydroxy methacrylate [manufactured by Daicel Chemical Industries, Ltd., trade name: Plaxel FM1] 17.3 g, 3.0 g of methyl methacrylate, 16.2 g of cyclohexyl methacrylate, isobol Nil methacrylate 30.0 g, butyl methacrylate 8.5 g, 2- (2′-hydroxy-5′-methacryloyloxyethylphenyl) -2H-benzotriazole [manufactured by Otsuka Chemical Co., Ltd., trade name: RUVA93] 7.0 g and A mixture of 0.7 g of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was dropped into the flask over 3 hours and then heated for another 2 hours, whereby the polymer solid content was 50. A 0.0% by weight solution was obtained. The weight average molecular weight of the obtained polymer was 59000.

Next, 19.6 g of 2-acryloyloxyethyl isocyanate and 19.6 g of butyl acetate were charged into the flask, and the resulting mixture was stirred while blowing a mixed gas in which nitrogen gas and air were mixed at a volume ratio of 2: 1. The flask was heated to 80 ° C. Thereafter, 0.03 g of dibutyltin dilaurate as a catalyst was added to the flask, reacted at 80 ° C. for 3 hours, and then subjected to a Fourier transform infrared spectrophotometer (FT-IR) to have a wave number of 2273 cm ⁻¹ derived from an isocyanate group. Of the unsaturated double bond containing 50.2 mass% of the unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain (hereinafter referred to as polymer). 4 solution). The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 4) has a hydroxyl value of 40 mgKOH / g, a weight average molecular weight of 60000, a molecular weight distribution of 4.1, and a glass transition temperature of It was 75 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 4 was 25.1 mol%.

Production Example 5
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, 2.3 g of 2-hydroxyethyl methacrylate, 10.0 g of methyl methacrylate, 30.6 g of cyclohexyl methacrylate, 15.1 g of butyl methacrylate, 2.0 g of acrylic acid, 40.0 g of isobornyl methacrylate and a polymerization initiator. As follows, a mixture of 12.0 g of 2,2′-azobis (2,4-dimethylvaleronitrile) was continuously dropped into the flask over 3 hours, and further heated for 2 hours to prepare a polymer solution. . The solid content of the polymer contained in the obtained polymer solution was 50.2% by mass, and the weight average molecular weight of the polymer was 6500.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 3.9 g of glycidyl methacrylate, 0.7 g of zinc octenoate as an esterification catalyst, and 4-hydroxy-2 as a polymerization inhibitor. A mixture of 0.01 g of 2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having a non-volatile content of 50.3% by mass of the unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain ( Hereinafter, the polymer 5 solution) was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 5) has a hydroxyl value of 10 mg KOH / g, a weight average molecular weight of 7000, a molecular weight distribution of 2.0, and a glass transition temperature of It was 105 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 5 was 4.5 mol%.

Production Example 6
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, 13.2 g of 2-hydroxyethyl methacrylate, caprolactone-modified hydroxy methacrylate [manufactured by Daicel Chemical Industries, Ltd., trade name: Plaxel FM1] 19.2 g, 10.0 g of methyl methacrylate, 20.0 g of 2-ethylhexyl acrylate, A mixture of 18.9 g of cyclohexyl methacrylate, 18.8 g of butyl methacrylate and 1.0 g of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was dropped into the flask over 3 hours. By heating for a time, a solution having a polymer solid content of 49.9% by mass was obtained. The weight average molecular weight of the obtained polymer was 18000.

Next, 4.2 g of 2-acryloyloxyethyl isocyanate and 4.2 g of butyl acetate were charged into the flask, and the resulting mixture was stirred while blowing a mixed gas in which nitrogen gas and air were mixed at a volume ratio of 2: 1. The flask was heated to 80 ° C. Thereafter, 0.03 g of dibutyltin dilaurate as a catalyst was added to the flask, reacted at 80 ° C. for 3 hours, and then subjected to a Fourier transform infrared spectrophotometer (FT-IR) to have a wave number of 2273 cm ⁻¹ derived from an isocyanate group. Of the unsaturated double bond containing 50.0% by mass of the unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain (hereinafter referred to as polymer). 6 solution). The obtained unsaturated double bond-containing polymer (hereinafter referred to as polymer 6) has a hydroxyl value of 80 mgKOH / g, a weight average molecular weight of 90000, a molecular weight distribution of 3.6, and a glass transition temperature of It was 9 ° C., and the content of side chains having a carbon-carbon double bond in Polymer 6 was 4.3 mol%.

Production Example 7
Into a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas introduction port, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to about 80 ° C. while stirring. . In this flask, 9.3 g of 2-hydroxyethyl methacrylate, 10.0 g of methyl methacrylate, 20.0 g of butyl acrylate, 11.6 g of cyclohexyl methacrylate, 18.0 g of glycidyl methacrylate, 31.1 g of butyl methacrylate and 2,2 as a polymerization initiator A mixture of 0.4 g of '-azobis (2,4-dimethylvaleronitrile) was dropped into the flask over 3 hours, and then heated for another 2 hours to prepare a polymer solution. The solid content of the polymer contained in the obtained polymer solution was 49.9% by mass, and the weight average molecular weight of the polymer was 64,000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 9.13 g of acrylic acid, 0.7 g of zinc octenoate as an esterification catalyst, and 4-hydroxy-2 as a polymerization inhibitor. A mixture of 0.01 g of 2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having a non-volatile content of 49.9% by mass of the unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain ( Hereinafter, the polymer 7 solution) was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 7) has a hydroxyl value of 40 mgKOH / g, a weight average molecular weight of 70000, a molecular weight distribution of 1.6, and a glass transition temperature of It was 20 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 7 was 17.1 mol%.

Production Example 8
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, caprolactone-modified hydroxymethacrylate [Daicel Chemical Industries, trade name: Plaxel FM1] 6.5 g, methylmethacrylate 30.0 g, cyclohexyl methacrylate 40.2 g,
A mixture of 22.8 g of butyl methacrylate and 0.6 g of acrylic acid and 0.5 g of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was continuously dropped into the flask over 3 hours. A polymer solution was prepared by further heating for 2 hours. The solid content of the polymer contained in the obtained polymer solution was 49.9% by mass, and the weight average molecular weight of the polymer was 84000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 1.2 g of glycidyl methacrylate, 0.7 g of zinc octenoate as an esterification catalyst, and 4-hydroxy-2 as a polymerization inhibitor. A mixture of 0.01 g of 2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After the completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having an unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain is 50.0% by mass ( Hereinafter, the polymer 8 solution) was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 8) has a hydroxyl value of 15 mg KOH / g, a weight average molecular weight of 84000, a molecular weight distribution of 4.2, and a glass transition temperature of It was 65 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 8 was 1.1 mol%.

Production Example 9
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, 1.2 g of 2-hydroxyethyl methacrylate, 39.0 g of methyl methacrylate, 10.5 g of cyclohexyl methacrylate, 8.3 g of butyl methacrylate, 30.0 g of isobornyl methacrylate, 10.0 g of maleic anhydride, 2,2, From 1.0 g of 6,6-hexamethyl-4-piperidyl methacrylate [manufactured by ADEKA, trade name: ADK STAB LA87] and 0.5 g of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator The resulting mixture was continuously dropped into the flask over 3 hours, and then heated for another 2 hours to prepare a polymer solution. The solid content of the polymer contained in the obtained polymer solution was 50.0% by mass, and the weight average molecular weight of the polymer was 59000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 90 ° C., 13.3 g of 2-hydroxyethyl methacrylate, 0.5 g of triethylamine as a catalyst, and 4-hydroxy 2,2 as a polymerization inhibitor. A mixture of 0.01 g of 6,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 10 minutes. After completion of the dropwise addition, the reaction is further continued for 7 hours, whereby the unsaturated double bond-containing polymer solution having an unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain is 50.0% by mass ( Hereinafter, the polymer 9 solution) was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 9) has a hydroxyl value of 5 mg KOH / g, a weight average molecular weight of 61,000, a molecular weight distribution of 1.9, and a glass transition temperature of It was 115 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 9 was 13.4 mol%.

Production Example 10
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, 9.3 g of 2-hydroxyethyl methacrylate, 20.0 g of methyl methacrylate, 5.0 g of butyl acrylate, 40.0 g of 2-ethylhexyl acrylate, 5.3 g of cyclohexyl methacrylate, 13.4 g of butyl methacrylate, 7 of acrylic acid 7 A mixture of 0.02 g and 0.06 g of 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was continuously dropped into the flask over 3 hours, and then heated for another 2 hours, A polymer solution was prepared. The solid content of the polymer contained in the obtained polymer solution was 50.0% by mass, and the weight average molecular weight of the polymer was 180,000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 13.8 g of glycidyl methacrylate, 0.7 g of zinc octenoate as an esterification catalyst, and 4-hydroxy-2 as a polymerization inhibitor. A mixture of 0.01 g of 2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After the completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having an unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain is 50.0% by mass ( Hereinafter, the polymer 10 solution) was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 10) has a hydroxyl value of 20 mg KOH / g, a weight average molecular weight of 200,000, a molecular weight distribution of 2.2, and a glass transition temperature of It was −10 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 10 was 11.1 mol%.

Production Example 11
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, 10.1 g of 2-hydroxyethyl methacrylate, 30.0 g of methyl methacrylate, 10.0 g of butyl acrylate, 35.2 g of cyclohexyl methacrylate, 14.7 g of butyl methacrylate and 2,2′-azobis (2, A 4-dimethylvaleronitrile) 0.04 g mixture was dropped into the flask over 3 hours and then heated for 2 hours to obtain a solution having a polymer solid content of 49.9% by mass. The weight average molecular weight of the obtained polymer was 240000.

Next, 8.5 g of 2-acryloyloxyethyl isocyanate and 8.5 g of butyl acetate were charged into the flask, and the resulting mixture was stirred while blowing a mixed gas in which nitrogen gas and air were mixed at a volume ratio of 2: 1. The flask was heated to 80 ° C. Thereafter, 0.03 g of dibutyltin dilaurate as a catalyst was added to the flask, reacted at 80 ° C. for 3 hours, and then subjected to a Fourier transform infrared spectrophotometer (FT-IR) to have a wave number of 2273 cm ⁻¹ derived from an isocyanate group. Of the unsaturated double bond containing 50.0% by mass of the unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain (hereinafter referred to as polymer). 11 solution). The obtained unsaturated double bond-containing polymer (hereinafter referred to as polymer 11) has a hydroxyl value of 10 mgKOH / g, a weight average molecular weight of 250,000, a molecular weight distribution of 2.1, and a glass transition temperature of It was 55 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 11 was 7.8 mol%.

Production Example 12
Into a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas introduction port, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to about 80 ° C. while stirring. . In this flask, 0.9 g of 2-hydroxyethyl methacrylate, 50.0 g of methyl methacrylate, 20.3 g of cyclohexyl methacrylate, 10.0 g of glycidyl methacrylate, 8.8 g of butyl methacrylate, 10.0 g of isobornyl methacrylate and 2 as a polymerization initiator. A mixture of 0.10 g of 2,2′-azobis (2,4-dimethylvaleronitrile) was dropped into the flask over 3 hours and then heated for another 2 hours to prepare a polymer solution. The solid content of the polymer contained in the obtained polymer solution was 49.9% by mass, and the weight average molecular weight of the polymer was 120,000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 5.1 g of acrylic acid, 0.7 g of zinc octenoate as an esterification catalyst, and 4-hydroxy-2 as a polymerization inhibitor. A mixture of 0.01 g of 2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having a non-volatile content of 49.9% by mass of the unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain ( Hereinafter, the polymer 12 solution) was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 12) has a hydroxyl value of 40 mg KOH / g, a weight average molecular weight of 130,000, a molecular weight distribution of 2.2, and a glass transition temperature of It was 90 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 12 was 8.7 mol%.

Production Example 13
In a 500 milliliter flask equipped with a stirrer, a dripping port, a thermometer, a cooling tube and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, caprolactone-modified hydroxymethacrylate [Daicel Chemical Industries, trade name: Plaxel FM1] 8.6 g, methyl methacrylate 10.0 g, cyclohexyl methacrylate 24.6 g, butyl methacrylate 5.8 g, isobornyl methacrylate 50 1.0 g, 2- (2-vinyloxyethoxy) ethyl acrylate [manufactured by Nippon Shokubai Co., Ltd., product number: VEEA] 1.0 g, and 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator 0.4 g of the mixture was added dropwise over 3 hours, and after completion of the addition, the mixture was further heated for 2 hours, whereby the unsaturated double bond-containing polymer having an allyl group at the end of the side chain had a nonvolatile content of 50.1. An unsaturated double bond-containing polymer solution (hereinafter referred to as polymer 13 solution) having a mass% was obtained. The resulting unsaturated double bond-containing polymer (hereinafter referred to as polymer 13) has a hydroxyl value of 20 mg KOH / g, a weight average molecular weight of 130,000, a molecular weight distribution of 4.3, and a glass transition temperature of The temperature was 110 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 13 was 1.0 mol%.

Production Example 14
In a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas inlet, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to 80 ° C. while stirring. In this flask, 15.1 g of 2-hydroxyethyl methacrylate, 20.0 g of methyl methacrylate, 10.0 g of butyl acrylate, 20.0 g of 2-ethylhexyl acrylate, 4.2 g of cyclohexyl methacrylate, 30.7 g of butyl methacrylate and a polymerization initiator. As a polymer solution, a mixture of 0.02 g of 2,2′-azobis (2,4-dimethylvaleronitrile) was continuously dropped into the flask over 3 hours and then heated for another 2 hours. . The solid content of the polymer contained in the obtained polymer solution was 50.0% by mass, and the weight average molecular weight of the polymer was 500,000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 6.4 g of 2-acryloyloxyethyl isocyanate, 0.7 g of zinc octenoate as an esterification catalyst, and 4 as a polymerization inhibitor. A mixture of 0.01 g of -hydroxy 2,2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After the completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having an unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain is 50.0% by mass ( Hereinafter, the polymer 14 solution) was obtained. The obtained unsaturated double bond-containing polymer (hereinafter referred to as polymer 14) has a hydroxyl value of 10 mgKOH / g, a weight average molecular weight of 510000, a molecular weight distribution of 2.0, and a glass transition temperature of It was 5 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 14 was 5.6 mol%.

Production Example 15
Into a 500 ml flask equipped with a stirrer, a dripping port, a thermometer, a cooling pipe and a nitrogen gas introduction port, 100 g of butyl acetate was charged, nitrogen gas was introduced, and butyl acetate was heated to about 80 ° C. while stirring. . In this flask, 2.3 g of 2-hydroxyethyl methacrylate, 10.0 g of methyl methacrylate, 11.1 g of cyclohexyl methacrylate, 17.0 g of glycidyl methacrylate, 9.6 g of butyl methacrylate, 50.0 g of isobornyl methacrylate and 2 as a polymerization initiator. A mixture of 0.02 g of 2,2′-azobis (2,4-dimethylvaleronitrile) was dropped into the flask over 3 hours and then heated for another 2 hours to prepare a polymer solution. The solid content of the polymer contained in the obtained polymer solution was 49.9% by mass, and the weight average molecular weight of the polymer was 490000.

  Next, while blowing nitrogen gas and oxygen gas into the flask, the internal temperature of the flask was raised to 110 ° C., 8.6 g of acrylic acid, 0.7 g of zinc octenoate as an esterification catalyst, and 4-hydroxy-2 as a polymerization inhibitor. A mixture of 0.01 g of 2,6,6-tetramethylpiperidine-1-oxyl was dropped into the flask over 30 minutes. After the completion of the dropwise addition, the reaction is further continued for 6 hours, whereby the unsaturated double bond-containing polymer solution having an unsaturated double bond-containing polymer having an acryloyl group at the end of the side chain is 50.0% by mass ( Hereinafter, the polymer 15 solution was obtained. The obtained unsaturated double bond-containing polymer (hereinafter referred to as polymer 15) has a hydroxyl value of 10 mgKOH / g, a weight average molecular weight of 510000, a molecular weight distribution of 2.0, and a glass transition temperature of It was 110 ° C., and the content of side chains having a carbon-carbon double bond in the polymer 15 was 20.1 mol%.

Production Example 16
In a 500 milliliter flask equipped with a stirrer, a dripping port, a thermometer, a condenser tube and a nitrogen gas inlet, 15 g of 2-hydroxyethyl methacrylate, 20.0 g of methyl methacrylate, 2 g of glycidyl methacrylate, 63 g of n-butyl methacrylate and toluene 100 g was charged, nitrogen gas was introduced, the temperature was raised to 100 ° C. with stirring, 0.3 g of azobisisobutyronitrile was added, the polymerization reaction was carried out for 2 hours, and 0.07 g of azobisisobutyronitrile was further added. The polymerization reaction was carried out for 2 hours.

  Next, 0.03 g of hydroquinone, 0.8 g of dimethylbenzylamine and 1 g of acrylic acid are added to the flask and heated with stirring at 100 ° C. for 15 hours to confirm that the acid value is 2 mgKOH / g or less. As a result, an unsaturated double bond-containing polymer solution (hereinafter referred to as polymer 16 solution) having a solid content of 50.0% by mass was obtained. The obtained polymer (hereinafter referred to as polymer 16) has a hydroxyl value of 73 mgKOH / g, a number average molecular weight of 22,000, a molecular weight distribution of 1.3, a glass transition temperature of 40 ° C. The content rate of the side chain having a carbon-carbon double bond in the polymer 16 was 1.8 mol%.

Example 1
Polymer 1 solution and polyisocyanate curing at a ratio of 3 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 1 solution obtained in Production Example 1. Into the container, 8 parts by mass of spherical particles [manufactured by Nippon Shokubai Co., Ltd., cross-linked polymethyl methacrylate particles, average particle size: 6 μm] are added, and the non-volatile content concentration becomes 20% by mass with ethyl acetate. The adhesive agent 1 was obtained by diluting.

Example 2
60 parts by mass of titanium oxide [Ishihara Sangyo Co., Ltd., trade name: CR-90-2] is added as a colorant to 100 parts by mass of the polymer 2 solution obtained in Production Example 2, and dispersed for 1 hour with a paint shaker. To obtain a dispersion.

  To 160 parts by mass of the dispersion obtained above, 6 parts by mass of a polyisocyanate curing agent [Asahi Kasei Chemicals Corporation, trade name: Duranate TPA-B80E] and spherical particles [manufactured by Nippon Shokubai Co., Ltd., crosslinked polymethyl methacrylate] Particles, average particle diameter: 6 μm] 8 parts by mass were added, and further, ethyl acetate was added so that the nonvolatile content was 20% by mass, whereby adhesive 2 was obtained.

Example 3
The polymer 3 solution and the polyisocyanate cured at a ratio of 12 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 3 solution obtained in Production Example 3. Into the container, 3 parts by weight of spherical particles (manufactured by Nippon Shokubai Co., Ltd., cross-linked polymethyl methacrylate particles, average particle size: 6 μm) are added, and the non-volatile content concentration is made 20% by mass with ethyl acetate. The adhesive agent 3 was obtained by diluting.

Example 4
The polymer 4 solution and the polyisocyanate cured at a ratio of 10 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 4 solution obtained in Production Example 4. Adhesive 4 was obtained by putting the agent in a container and diluting with ethyl acetate so that the non-volatile content concentration was 20% by mass.

Example 5
Polymer 5 solution and polyisocyanate curing at a ratio of 6 parts by mass of polyisocyanate curing agent [Asahi Kasei Chemicals Co., Ltd., trade name: Duranate TPA-B80E] per 100 parts by mass of polymer 5 solution obtained in Production Example 5. Into the container, 6 parts by mass of spherical particles (manufactured by Nippon Shokubai Co., Ltd., cross-linked polymethyl methacrylate particles, average particle size: 6 μm) are added, and the non-volatile content concentration becomes 20% by mass with ethyl acetate. The adhesive 5 was obtained.

Example 6
The polymer 6 solution and the polyisocyanate cured at a ratio of 19 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 6 solution obtained in Production Example 6. Into the container, 5 parts by weight of spherical particles (manufactured by Nippon Shokubai Co., Ltd., cross-linked polymethyl methacrylate particles, average particle size: 6 μm) are added, and the non-volatile content with ethyl acetate is 20% by weight. The adhesive agent 6 was obtained by diluting.

Example 7
The polymer 7 solution and the polyisocyanate cured at a ratio of 36 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, trade name: Duranate TPA-B80E] per 100 parts by mass of the polymer 7 solution obtained in Production Example 7. Into the container, 3 parts by weight of spherical particles (manufactured by Nippon Shokubai Co., Ltd., cross-linked polymethyl methacrylate particles, average particle size: 6 μm) are added, and the non-volatile content concentration is made 20% by mass with ethyl acetate. The adhesive agent 7 was obtained by diluting.

Example 8
To 100 parts by mass of the polymer 8 solution obtained in Production Example 8, 24 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, trade name: Duranate TPA-B80E] and spherical particles [manufactured by Nippon Shokubai Co., Ltd., Cross-linked polymethyl methacrylate particles, average particle size: 6 μm] 2 parts by mass were added, and further, ethyl acetate was added so that the nonvolatile content was 20% by mass, thereby obtaining an adhesive 8.

Example 9
60 parts by mass of titanium oxide (trade name: CR-90-2, manufactured by Ishihara Sangyo Co., Ltd.) is added as a colorant to 100 parts by mass of the polymer 9 solution obtained in Production Example 9, and dispersed for 1 hour using a paint shaker. To obtain a dispersion.

  10 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Co., Ltd., trade name: Duranate TPA-B80E] is added to 160 parts by mass of the dispersion liquid obtained above, and the nonvolatile content concentration becomes 20% by mass with ethyl acetate. By diluting as described above, an adhesive 9 was obtained.

Example 10
Polymer 10 solution and polyisocyanate curing at a ratio of 6 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 10 solution obtained in Production Example 10. Into the container, 10 parts by mass of spherical particles (manufactured by Nippon Shokubai Co., Ltd., cross-linked polymethyl methacrylate particles, average particle size: 6 μm) are added, and the non-volatile concentration in ethyl acetate is 20% by mass. The adhesive agent 10 was obtained by diluting.

Example 11
The polymer 11 solution and the polyisocyanate cured at a ratio of 6 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 11 solution obtained in Production Example 11. Into the container, 5 parts by weight of spherical particles (manufactured by Nippon Shokubai Co., Ltd., cross-linked polymethyl methacrylate particles, average particle size: 6 μm) are added, and the non-volatile content with ethyl acetate is 20% by weight. The adhesive agent 11 was obtained by diluting.

Example 12
The polymer 12 solution and the polyisocyanate cured at a ratio of 72 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 12 solution obtained in Production Example 12. The adhesive agent 12 was obtained by putting an agent in a container and diluting it with ethyl acetate so that a non volatile matter density | concentration might be 20 mass%.

Example 13
60 parts by mass of titanium oxide [manufactured by Ishihara Sangyo Co., Ltd., trade name: CR-90-2] as a colorant is added to 100 parts by mass of the polymer 13 solution obtained in Production Example 13, and dispersed for 1 hour with a paint shaker. To obtain a dispersion.

  To 160 parts by mass of the dispersion obtained above, 6 parts by mass of a polyisocyanate curing agent [Asahi Kasei Chemicals Corporation, trade name: Duranate TPA-B80E] and spherical particles [manufactured by Nippon Shokubai Co., Ltd., crosslinked polymethyl methacrylate] Particles, average particle diameter: 6 μm] 3 parts by mass were added, and further, ethyl acetate was added so that the nonvolatile content was 20% by mass, whereby an adhesive 13 was obtained.

Example 14
The polymer 14 solution and the polyisocyanate cured at a ratio of 3 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 14 solution obtained in Production Example 14. Into the container, 10 parts by mass of spherical particles (manufactured by Nippon Shokubai Co., Ltd., cross-linked polymethyl methacrylate particles, average particle size: 6 μm) are added, and the non-volatile concentration in ethyl acetate is 20% by mass. The adhesive agent 14 was obtained by diluting.

Example 15
Polymer 15 solution and polyisocyanate curing at a ratio of 9 parts by mass of a polyisocyanate curing agent [Asahi Kasei Chemicals Co., Ltd., trade name: Duranate TPA-B80E] per 100 parts by mass of the polymer 15 solution obtained in Production Example 15. Adhesive 15 was obtained by placing the agent in a container and diluting with ethyl acetate to a non-volatile content concentration of 20% by mass.

Comparative Example 1
The polymer 16 solution and the polyisocyanate cured at a ratio of 44 parts by mass of a polyisocyanate curing agent [manufactured by Asahi Kasei Chemicals Corporation, product name: Duranate TPA-B80E] per 100 parts by mass of the polymer 16 solution obtained in Production Example 16. The adhesive 16 was obtained by putting the agent in a container and diluting with ethyl acetate so that the non-volatile content concentration was 20% by mass.

Experimental example (Preparation of back sheet for solar cell module)
Using the adhesive shown in Table 1, the adhesive is applied to the substrate 1 so that the coating amount after drying is 1 g / m ^2, and dried at 100 ° C. for 1 minute to form an adhesive layer. I let you. Thereafter, in order from the filler side to the base materials 1 to 3, the surface of the base material 1 on which the adhesive layer is not formed is overlapped with the adhesive X, so that the base material 1 / adhesive X / base material 2 By laminating in the order of / adhesive X / base material 3 and laminating by a dry laminating method, a laminate was obtained. The obtained laminated body was cured at 50 ° C. for 5 days to produce a back sheet for a solar cell module.

As the adhesive X, a main component of a polyester-based adhesive (manufactured by Dainippon Ink and Chemicals, product number: LX703VL) and a polyisocyanate curing agent (manufactured by Dainippon Ink and Chemicals, product number: KE90). The coating amount after drying of the adhesive X was adjusted to 10 g / m ² .

  Next, the physical properties of the solar cell module backsheet obtained above were examined by the following methods. The results are shown in Table 1.

1. Blocking resistance The back sheet for a solar cell module obtained above was cut into a width of 5 cm and a length of 20 cm, and the surface on which the adhesive layer surface of the cut sheet was formed and an untreated heat-resistant oligomer PET film [Toray ( Co., Ltd., trade name: Lumirror X10S] (hereinafter referred to as untreated PET film), a weight of 5 kg is placed on the resulting laminate, and this laminate is placed in an oven at a temperature of 40 ° C. And kept for 24 hours. Then, the laminated body was taken out from the oven, the adhesive layer of the laminated body was visually observed, and blocking resistance was evaluated based on the following evaluation criteria.

(Evaluation criteria)
A: The adhesive layer is not transferred to the untreated PET film.
X: The adhesive layer is transferred to an untreated PET film.

2. Adhesiveness One sheet obtained by cutting the back sheet obtained above to a width of 60 mm and a length of 200 mm, and an EVA sheet (manufactured by Mitsui Chemicals Fabro, product number: RC02B, thickness: 400 μm) are a width of 60 mm and a length. One sheet cut to 90 mm and tempered glass (width: 10 mm, length: 100 mm, thickness: 3 mm) were prepared.

  A laminated body was obtained by superimposing the back sheet / EVA sheet / tempered glass plate in this order so that the surface of the back sheet for solar cell module to be evaluated was in contact with the EVA sheet.

  Next, using the solar cell vacuum laminator, the laminate obtained above was heated to 150 ° C., evacuated for 5 minutes, and then subjected to pressure bonding for 3 minutes to prepare a sample.

  In an atmosphere where the temperature is 23 ° C. and the relative humidity is 65%, the tempered glass plate and EVA sheet of the unbonded portion of the sample obtained above are respectively attached to the upper and lower clips of the autograph (manufactured by Shimadzu Corporation). The peeling strength (initial value) at a crosshead speed of 300 mm / min with a width of 25 mm was measured by sandwiching and 180-degree peeling method, and the adhesiveness was evaluated based on the following evaluation criteria.

  Further, after leaving a sample different from the sample whose peel strength was measured in an atmosphere having a temperature of 85 ° C. and a relative humidity of 85% for 1000 hours, 2000 hours or 3000 hours, the peel strength was measured under the same conditions as described above. Then, the adhesiveness was evaluated based on the following evaluation criteria.

(Evaluation criteria)
EX: Peel strength of 80 N / 10 mm or more (remarkably excellent adhesion)
A: Peel strength is 40 N / 10 mm or more and less than 80 N / 10 mm (excellent adhesiveness)
B: Peel strength is 20 N / 10 mm or more and less than 40 N / 10 mm (adhesiveness is good)
C: Peel strength is 10 N / 10 mm or more and less than 20 N / 10 mm (adhesiveness is slightly good)
D: Peel strength is less than 10 N / 10 mm (adhesion is poor)

3. Weather resistance A4 size EVA sheet (made by Mitsui Chemicals Fabro Co., Ltd., product number: RC02B, thickness: 400 μm) sandwiched between A4 size tempered glass plates as a solar cell module filler. After the solar cell made of polycrystalline silicon was placed, a laminate was obtained by further providing the back sheet obtained above so that the adhesive layer was in contact with the EVA sheet.

  Next, each laminated body obtained above was heated to a temperature of 150 ° C. using a solar cell vacuum laminator, evacuated for 5 minutes, and then subjected to pressure bonding for 3 minutes to prepare a sample.

The sample is irradiated with ultraviolet rays for 100 hours or 200 hours at 100 mW / cm ² at a temperature of 60 ° C. and a relative humidity of 50% using an i-super UV tester [manufactured by Iwasaki Electric Co., Ltd., product number: SUV-W151]. Thus, a weather resistance acceleration test was conducted.

[Adhesion retention]
Using an autograph (manufactured by Shimadzu Corporation), the peel strength of the sample at a crosshead speed of 300 mm / min was measured by a 180-degree peel method, and the formula:
[Retention rate (%)]
= [(Peel strength after accelerated test) ÷ (Peel strength before accelerated test)] × 100
Based on the above, the retention rate was determined, and the adhesion retention was evaluated based on the following evaluation criteria.

(Evaluation criteria)
○: Retention rate is 60% or more.
Δ: Retention rate is 50% or more and less than 60%.
X: Retention rate is less than 50%.

[Appearance change]
While visually observing the change of the sample before and after irradiation of the sample, the yellowing degree (Δb value) of the sample was measured with a spectrophotometer [manufactured by JEOL Ltd., product number: SE-2000], Appearance change was evaluated based on the following evaluation criteria. Note that the smaller the yellowing degree (Δb value) of the sample, the smaller the change in appearance of the sample.
(Evaluation criteria)
(Double-circle): (DELTA) b is less than 2 and a float is not recognized.
A: Δb is 2 or more and less than 5, and no floating is observed.
Δ: Δb is 5 or more, and no floating is observed.
X: Floating is recognized regardless of the value of Δb.

3. Electrical output characteristics The maximum output of the sample before and after the weather resistance promotion test was measured according to JIS C8913, and the formula:
[Change rate of maximum output (%)]
= [(Maximum output after accelerated test) / (Maximum output before accelerated test)] x 100
The change rate of the maximum output was obtained based on the above, and the electrical output characteristics were evaluated based on the following evaluation criteria.

(Evaluation criteria)
A: The change rate of the maximum output is 95% or more.
A: The change rate of the maximum output is 90% or more and less than 95%.
Δ: The rate of change of the maximum output is 80% or more and less than 90%.
X: The change rate of the maximum output is less than 80%.

  From the results shown in Table 1, the back sheet adhesives obtained in each example are all excellent in blocking resistance, and in contrast to the back sheet adhesive obtained in Comparative Example 1, Adhesiveness to fillers used in solar cells, not only in the environment where they are actually used as batteries, but also in accelerated tests in hot and humid atmospheres that are considered when evaluating solar cell modules In addition, it can be seen that the weather resistance is excellent, the electrical output characteristics are maintained, and the appearance of the back sheet is excellent. Therefore, it turns out that all can use the adhesive agent for backsheets obtained in each Example suitably for a solar cell module and a solar cell.

1: Base material 2: Adhesive 3: Barrier layer 4: Adhesive layer

Claims (4)

  A back sheet for a solar cell module in which an adhesive layer is formed, the adhesive layer having an ethylenically unsaturated double bond at the end of a side chain, and a molecular weight distribution (weight average molecular weight / number average molecular weight). ) Is formed of an adhesive for backsheets containing an unsaturated double bond-containing polymer having a molecular weight of 1.5 to 6.0. A solar cell module backsheet.   The unsaturated double bond-containing polymer having an ethylenically unsaturated double bond at the end of the side chain is at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer An unsaturated double bond-containing polymer obtained by reacting a polymer obtained by polymerizing a monomer component containing a polymer with a monomer having a carboxyl group and / or a hydroxyl group, and having a carboxyl group and / or a hydroxyl group Reacting a polymer obtained by polymerizing a monomer component containing a monomer with at least one monomer selected from the group consisting of an epoxy group-containing monomer and an oxazoline group-containing monomer; An unsaturated double bond-containing polymer, a polymer obtained by polymerizing a monomer component containing a monomer having a carboxyl group and / or a hydroxyl group, and an isocyanate group-containing monomer. An unsaturated double bond-containing polymer, a polymer obtained by polymerizing a monomer component containing an isocyanate group-containing monomer, and a monomer having a carboxyl group and / or a hydroxyl group are reacted. Contains a double bond-containing polymer, an unsaturated double bond-containing polymer obtained by polymerizing a monomer component containing (meth) acrylic acid (vinyloxyalkoxy) alkyl, and a monomer having an acid anhydride group At least one selected from the group consisting of an unsaturated double bond-containing polymer obtained by reacting a polymer obtained by polymerizing the monomer component to be reacted with a monomer having a hydroxyl group. The back sheet for a solar cell module according to claim 1, which is a saturated double bond-containing polymer.   A solar cell module comprising the back sheet for a solar cell module according to claim 1.   A solar cell comprising the solar cell module according to claim 3.