JP2013095759A - Polyurethane adhesive composition for resin glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyurethane adhesive composition for resin glass, with which a glass adherend can be bonded to a poorly-adhesive adherend without conducting surface preparation, and which possesses excellent adhesion after curing at the normal temperature.SOLUTION: The polyurethane adhesive composition for resin glass includes: a preliminary composition including an urethane prepolymer obtained by making a mixture of a polyether triol and a polyether diol, with a number average molecular weight of 1,000 to 7,000, and 4,4'-MDI react with each other while maintaining the ratio (NCO group)/(OH group) at 1.1 to 2.5; an adhesion imparting agent A obtained by addition of 3-(N-phenyl)aminopropyltrimethoxysilane to the biuret body of HDI while maintaining the ratio (NCO group)/(NH group) at 1.5/1.0 to 9.0/1.0; and an organic tin compound, wherein 2 to 10 pts.mass of the adhesion imparting agent A is contained with respect to 100 pts.mass of the urethane prepolymer, and 0.001 to 0.5 pts.mass of the organic tin compound is contained with respect to 100 pts.mass of the urethane prepolymer.

Description

  The present invention relates to a polyurethane adhesive composition for resin glass.

  Conventionally, various polyurethane resin compositions using moisture curing have been widely used as sealing materials, adhesives and the like in various fields such as automobiles and buildings. In particular, such a polyurethane resin composition is generally bonded when used as an adhesive for adhering a glass adherend to a painted adherend, such as attachment of a window glass to a vehicle body in the manufacture of a vehicle. Prior to the application of the agent, a different primer containing a solution of one or two or more silanes is applied to an adherend or glass adherend coated.

  For example, in the operation of assembling a vehicle, when a window glass such as a front window or a rear window is adhered to the vehicle, a different primer containing a solution of one or more silanes is applied to the window before the adhesive is applied to the window glass. It is applied to glass. And after apply | coating an adhesive agent to the window glass by which primer processing was carried out, a window glass is attached to a vehicle.

  In the operation of assembling the vehicle, the primer is manually applied to the vehicle body side in most cases, but since the solvent contained in the primer is a volatile organic solvent (VOC), the VOC is an assembly line worker. Reduction of VOC has been demanded from the viewpoints of impact on the environment and impact on the environment. In addition, when the primer adheres to a part other than the part to be applied in the work place, the worker on the assembly line is exposed to extra chemicals, and the repair requires extra effort and cost, which is not desirable. Therefore, there has been a demand for a one-component moisture-curable urethane composition that can adhere a glass adherend to a coated adherend without using a primer.

  In addition, organic resin glass is used to reduce the weight, but resin glass is an adherend that is very difficult to adhere due to poor slipping, and conventional polyurethane resin compositions have such difficult adhesion. The adhesiveness to the kimono has not been studied. Therefore, in the conventional one-component moisture-curable polyurethane resin composition, a primer layer must be formed in order to stably adhere the adherend to the hardly adherent adherend (for example, Patent Documents). 1).

JP 2001-323214 A

  Therefore, it is possible to have a stable and high adhesion without heat treatment even after curing at room temperature, without performing primer treatment to form a primer layer on difficult-to-adhere adherends such as painted adherends. The appearance of a polyurethane adhesive composition for resin glass that can be made is eagerly desired.

  In view of the above problems, the present invention is capable of adhering a glass adherend to a hardly adherent adherend without performing a ground treatment, and for resin glass having excellent adhesion even after curing at room temperature. An object is to provide a polyurethane adhesive composition.

  In order to solve the above-mentioned object, the present inventors have conducted intensive research on the adhesiveness of a one-part moisture-curable polyurethane adhesive composition to a difficult-to-adhere adherend. As a result, a pre-composition comprising a urethane prepolymer obtained by reacting a mixture of polyether triol and polyether diol with 4,4'-diphenylmethane diisocyanate in a predetermined range with socyanate groups / hydroxy groups (NCO groups / OH groups). In the composition containing the specific adhesion imparting agent A and the organic tin compound, when the contents of the adhesion imparting agent A and the organic tin compound are in a specific relationship, The present inventors have found that a polyurethane adhesive composition for resin glass that can have excellent adhesiveness without performing primer treatment or the like can be provided, and the present invention has been completed.

That is, this invention is made | formed based on the said knowledge, and provides the following (1).
(1) A range in which an equivalent ratio of an isocyanate group to a hydroxyl group is 1.1 to 2.5 in a mixture of a polyether triol having a number average molecular weight of 1,000 or more and 7,000 or less and a polyether diol, and 4,4′-diphenylmethane diisocyanate A pre-composition comprising a urethane prepolymer obtained by reacting within,
The equivalent ratio of 3- (N-phenyl) aminopropyltrimethoxysilane and hexamethylene diisocyanate biuret is between 1.5 / 1.0 and 9.0 / 1.0. An adhesion-imparting agent A obtained by adding
An organic tin compound,
The content of the adhesion-imparting agent A is 2 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the urethane prepolymer,
Content of the said organic tin compound is 0.001 mass part or more and 0.5 mass part or less with respect to 100 mass parts of said urethane prepolymers, The polyurethane adhesive composition for resin glass characterized by the above-mentioned.

  ADVANTAGE OF THE INVENTION According to this invention, a glass adherend can be adhere | attached, without performing a surface treatment with respect to a to-be-adhered adherend, and it can have the outstanding adhesiveness after hardening at normal temperature.

  The present invention will be described in detail below. The present invention is not limited by the following modes for carrying out the invention (hereinafter referred to as embodiments). In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the constituent elements disclosed in the following embodiments can be appropriately combined.

  The polyurethane adhesive composition for resin glass according to the present embodiment (hereinafter referred to as “the composition of the present embodiment”) is a mixture of polyether triol having a number average molecular weight of 1000 or more and 7000 or less and polyether diol. , 4'-diphenylmethane diisocyanate, a pre-composition comprising a urethane prepolymer obtained by reacting an isocyanate group and a hydroxyl group in an equivalent ratio of 1.1 to 2.5, and 3- (N-phenyl) Adhesion obtained by adding aminopropyltrimethoxysilane and hexamethylene diisocyanate biuret in an equivalent ratio of isocyanate group to amino group of 1.5 / 1.0 or more and 9.0 / 1.0 or less. Including an imparting agent A and an organic tin compound, and the content of the adhesion imparting agent A is 100 parts by mass of the urethane prepolymer. 2 parts by mass or more and 10 parts by mass or less, and the content of the organotin compound is 0.001 part by mass or more and 0.5 parts by mass or less with respect to 100 parts by mass of the urethane prepolymer. .

<Preliminary composition>
(Urethane prepolymer)
The urethane prepolymer blended in the preliminary composition contained in the composition of the present embodiment (hereinafter also referred to as “the urethane prepolymer used in the present embodiment”) has a number average molecular weight of 1,000 to 7,000. A mixture of ether triol and polyether diol is reacted with 4,4′-diphenylmethane diisocyanate within an equivalent ratio of isocyanate group to hydroxyl group (NCO group / OH group) of 1.1 or more and 2.5 or less. It is obtained.

  The polyether triol used to synthesize the urethane prepolymer used in the present embodiment (hereinafter also referred to as “polyether triol used in the present embodiment”) has a number average molecular weight of 1000 to 7000. From the point of being excellent in the viscosity of the composition of this embodiment obtained and the physical property of the hardened | cured material of a composition, Preferably it is 2000-5000.

  Specific examples of the polyether triol include polyoxypropylene triol, polyoxyethylene triol, polytetramethylene triol, polyethylene triol, polypropylene triol, and polyoxybutylene triol. Among these, polyoxypropylene triol and polyoxyethylene triol are preferable from the viewpoint of balance between physical properties and cost. As the polyether triol used in the present embodiment, the polyether triol may be used alone or in combination of two or more.

  The polyether diol used to synthesize the urethane prepolymer used in the present embodiment (hereinafter also referred to as “polyether diol used in the present embodiment”) has a number average molecular weight of 1000 to 7000. From the point of being excellent in the viscosity of the composition of this embodiment obtained and the physical property of the hardened | cured material of a composition, Preferably it is 2000-5000.

  Specific examples of the polyether diol include polypropylene ether diol, polyethylene ether diol, polytetramethylene glycol, polyethylene glycol, polypropylene glycol, polyoxypropylene glycol, and polyoxybutylene glycol. Among these, polypropylene ether diol and polyethylene ether diol are preferable from the viewpoint of good balance between physical properties and cost. In the polyether diol used in the present embodiment, the above polyether diol may be used alone or in combination of two or more.

The polyisocyanate compound used when synthesizing the urethane prepolymer used in the present embodiment is 4,4′-diphenylmethane diisocyanate (4,4′-MDI). Examples of the polyisocyanate compound include TDI (for example, 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI)), MDI (for example, 2,2 '-Diphenylmethane diisocyanate (2,2'-MDI), 4,4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diisocyanate (2,4'-MDI)), 1,4- Phenylene diisocyanate, polymethylene polyphenylene polyisocyanate, xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), tolidine diisocyanate (TODI), 1,5-naphthalene diisocyanate (NDI), triphenylmethane triisocyanate, etc. Aromatic polyisocyanates; aliphatic polyisocyanates such as hexamethylene diisocyanate (HDI), trimethylhexamethylene diisocyanate (TMHDI), lysine diisocyanate, norbornane diisocyanate methyl (NBDI), ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate; Alicyclic polyisocyanates such as transcyclohexane-1,4-diisocyanate, isophorone diisocyanate (IPDI), bis (isocyanatemethyl) cyclohexane (H ₆ XDI), dicyclohexylmethane diisocyanate (H ₁₂ MDI); these carbodiimide-modified polyisocyanates These isocyanurate-modified polyisocyanates and the like.

  Among the polyisocyanate compounds, 4,4'-MDI is used as the polyisocyanate compound used when synthesizing the urethane prepolymer used in the present embodiment from the viewpoint of easy availability and low cost.

  In the production of the urethane prepolymer used in the present embodiment, the amount of the polyether triol and polyether diol and 4,4′-MDI is the amount of NCO group of 4,4′-MDI and the OH of the above mixture. The mixing is performed so that the equivalent ratio of groups (NCO group / OH group) is in the range of 1.1 to 2.5, more preferably 1.5 to 2.2, and more preferably 1 .5 or more and 2.0 or less. NCO group / OH group means the ratio (equivalent ratio) of isocyanate groups in the polyisocyanate compound per hydroxyl group in the polyol compound. When the equivalence ratio is in such a range, the viscosity of the obtained urethane prepolymer becomes appropriate, and the composition becomes more difficult to foam. If the NCO group / OH group is within this range, the resulting composition of the present embodiment will have good adhesion and crosslink density, the resulting urethane prepolymer will have an appropriate viscosity, and the cured product will be less likely to foam, It is preferable because the cured product does not become brittle.

  The urethane prepolymer used in the present embodiment is not particularly limited for its production. For example, in the urethane prepolymer, a polyol compound and a polyisocyanate compound are mixed and dehydrated, and then the molten 4,4′-MDI has an equivalent ratio of the NCO group of 4,4′-MDI to the OH group of the above mixture. It can be obtained by adding an amount that falls within the range and stirring while replacing with nitrogen.

  The preliminary composition contained in the composition of the present embodiment (hereinafter also referred to as “preliminary composition used in the present embodiment”) may contain a filler, a plasticizer, and the like in addition to the urethane prepolymer. Good.

  The filler blended in the preliminary composition used in the present embodiment is not particularly limited. For example, calcium carbonate, aluminum hydroxide, carbon black, white carbon, silica, glass, kaolin, talc (magnesium silicate), Fumed silica, precipitated silica, silicic anhydride, hydrous silicic acid, clay, calcined clay, glass, bentonite, glass fiber, asbestos, glass filament, crushed quartz, diatomaceous earth, aluminum silicate, zinc oxide, magnesium oxide, oxidation Inorganic fillers such as titanium or surface treated products thereof; carbonates, organic bentonite, high styrene resin, coumarone-indene resin, phenol resin, formaldehyde resin, modified melamine resin, cyclized rubber, lignin, ebonite powder, shellac, Cork powder, bone meal, wood Organic fillers such as cellulose powder, coconut palm, wood pulp; inorganic pigments such as lamp black, titanium white, bengara, titanium yellow, zinc white, red lead, cobalt blue, iron black, aluminum powder and neozabon black RE And organic pigments such as Neo Black RE, Orazole Black CN, Orazole Black Ba (all manufactured by Ciba Geigy) and Spiron Blue 2BH (manufactured by Hodogaya Chemical Co., Ltd.). Of these, carbon black and calcium carbonate are preferably used in order to impart desired characteristics. These carbon black and calcium carbonate are not particularly limited, and commercially available products can be used. For example, carbon black includes N110, N220, N330, N550, N770, etc., or a mixture thereof according to the American Society for Testing Materials standard, and calcium carbonate includes heavy calcium carbonate, precipitated calcium carbonate, and the like. Among these, heavy calcium carbonate is preferable from the viewpoint of imparting deep part curability to the composition of the present embodiment to be obtained. These fillers can be used singly or in combination of two or more.

  The amount of the carbon black blended is 100 parts by mass with respect to 100 parts by mass of the urethane prepolymer in that the obtained composition of the present embodiment has sufficient mechanical strength and can impart viscosity and thixotropy excellent in handleability. It is preferably 10 to 100 parts by mass. 20 to 90 mass parts is more preferable at the point which is excellent by this characteristic.

  The blending amount of the calcium carbonate is 2 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the urethane prepolymer in that the deep part curability of the composition of the present embodiment to be obtained is good. preferable. From the point which is excellent by this characteristic, 3 to 20 mass parts is more preferable.

  The plasticizer blended in the preliminary composition used in this embodiment is not particularly limited, but phthalic acid derivatives such as dibutyl phthalate, dioctyl phthalate, diisodecyl phthalate, dioctyl phthalate, tetrahydrophthalic acid, azelaic acid, maleic acid , Derivatives of trimellitic acid, isophthalic acid, adipic acid, itaconic acid, citric acid and the like.

  The blending amount of the plasticizer is 3 with respect to 100 parts by mass of the urethane prepolymer from the viewpoint that the obtained composition of the present embodiment has an appropriate flexibility and has a viscosity excellent in handleability. It is preferable that it is not less than 40 parts by mass. From the point which is excellent by this characteristic, 5 to 30 mass parts is more preferable.

  The production method of the preliminary composition used in the present embodiment is not particularly limited, and is not particularly limited as long as the blending amount of each component does not deviate from the purpose of the present embodiment. A urethane prepolymer, a filler, A preliminary composition used in the present embodiment can be obtained by adding a plasticizer and stirring under reduced pressure.

<Adhesion imparting agent A>
The adhesion-imparting agent A is a biuret body of 3- (N-phenyl) aminopropyltrimethoxysilane having a structure represented by the following formula (a) and hexamethylene diisocyanate having a structure represented by the following formula (b) ( It is an isocyanate silane compound that is a reaction product with a biuret of HDI. The adhesion-imparting agent A comprises 3- (N-phenyl) aminopropyltrimethoxysilane and a biuret of HDI having an isocyanate group / amino group (NCO group / NH group) of 1.5 / 1.0 or more and 9.0. It is obtained by adding within the range of /1.0 or less. NCO group / NH group refers to the ratio of isocyanate groups in HDI per amino group in 3- (N-phenyl) aminopropyltrimethoxysilane.

  The NCO group / NH group reacts with 3- (N-phenyl) aminopropyltrimethoxysilane and HDI biuret so that it falls within the range of 1.5 / 1.0 to 9.0 / 1.0. However, it is preferably 1.5 / 1.0 to 6.0 / 1.0, and more preferably 3.0 / 1.0 to 6.0 / 1.0. If the NCO group / NH group is within the above range, the adhesion of the adhesion-imparting agent A is sufficiently exhibited. At this time, an unreacted HDI biuret body may remain.

  The content of the adhesion-imparting agent A is preferably 2 parts by mass or more and 10 parts by mass or less, more preferably 3 parts by mass or more and 8 parts by mass or less, and still more preferably 5 with respect to 100 parts by mass of the urethane prepolymer. It is not less than 8 parts by mass.

  The average molecular weight of the adhesion-imparting agent A is preferably 600 to 2000, more preferably 600 to 1800, and still more preferably 600 to 1500.

  The production of the adhesion-imparting agent A can be carried out in the same manner as in the production of ordinary polyurethane. For example, 3- (N-phenyl) aminopropyltrimethoxysilane and HDI biuret in the above-mentioned equivalent ratio It can be performed by stirring at room temperature. Moreover, the urethanation catalyst, such as the below-mentioned organotin compound, organic bismuth, and amine, etc. can also be used as needed.

<Organic tin compound>
Since the organotin compound contained in the composition of the present embodiment catalyzes the reaction between the isocyanate group of the urethane prepolymer and the active hydrogen on the surface of the adherend, the composition of the present embodiment comprises a difficult-to-adhere coating plate, etc. Excellent adhesion to various adherends.

  The content of the organic tin compound is preferably 0.001 parts by mass or more and 0.5 parts by mass or less, more preferably 0.0010 parts by mass or more and 0.05 parts by mass with respect to 100 parts by mass of the preliminary composition. Or less, more preferably 0.002 parts by mass or more and 0.03 parts by mass or less. When the content of the organic tin compound is within the above range, the adhesiveness to various adherends such as a hardly adhesive coating plate is excellent.

  The organotin compound contained in the composition of the present embodiment is not particularly limited as long as it is a compound having an organic group. For example, divalent tin carboxylates such as tin octylate and tin naphthenate, dioctyltin Dilaurate, dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, dibutyltin dioctoate, stannous octate, dibutyltin diacetylacetonate, dioctyltin maleate dibutyltin oxide, dioctyltin oxide, dibutyltin benzoate, dibutyltin mercaptide, Examples thereof include tetravalent tin carboxylates such as dibutyltin thiocarboxylate, dioctyltin mercaptide and dioctyltin thiocarboxylate, a reaction product of dibutyltin oxide and phthalate; dibutyltin diacetylacetonate and the like. These organotin compounds may be used alone or in combination of two or more. Among these, dioctyltin dilaurate is preferable from the viewpoint of excellent adhesion to a hardly adhesive coating plate or the like.

  The organotin compound contained in the composition of the present embodiment may be used alone or in combination of two or more.

<Organic solvent>
In addition to the above components, the composition of this embodiment can contain an organic solvent in order to improve ease of preparation and workability of the coating process. The organic solvent is not particularly limited as long as it is inert to the above components and has an appropriate volatility. Specific examples of the organic solvent include methyl ethyl ketone, dimethylacetamide, acetone, ethyl acetate, butyl acetate, cellosolve acetate, mineral spirit, toluene, xylene, n-hexane, isohexane, methylene chloride, tetrahydrofuran, ethyl ether, dioxane. Etc. Among these organic solvents, toluene, mineral spirit, and methyl ethyl ketone are preferable. These organic solvents are preferably used after sufficiently dried. In the composition of this embodiment, 1 type of the said organic solvent may be used, and 2 or more types may be used together. The organic solvent may not be used from the viewpoint of VOC reduction.

  The composition of the present embodiment includes a urethane prepolymer, an adhesion-imparting agent A in which a biuret of 3- (N-phenyl) aminopropyltrimethoxysilane and HDI is added at a ratio of NCO / NH = 3/1, In addition to the organic tin compound, other additives besides the organic solvent can be contained as necessary within the range not impairing the object of the present invention. Other additives include, for example, ultraviolet absorbers, thickeners, stabilizers, reinforcing agents, curing catalysts, plasticizers, dispersants, solvents, antioxidants, anti-aging agents, pigments, thixotropic agents, dyes, Examples thereof include an antistatic agent, a flame retardant, an adhesion imparting agent, and a dispersant.

  Examples of the ultraviolet absorber include Siasolv (Cyasorb UV24 Light Absorber, manufactured by American Cyanamid Co., Ltd.), Ubinul (Uvinul D-49, D-50, N-35, N-539, manufactured by General Aniline Co., Ltd.), and the like. . These are effective in shielding or absorbing ultraviolet light and visible light and improving light resistance. Examples of the stabilizer include diethyl malonate.

  Although the manufacturing method of the composition of this embodiment is not specifically limited, Specifically, for example, the compound (A) is dissolved in an organic solvent and added to the preliminary composition, and the organotin compound is further added. It is preferable to sufficiently knead under reduced pressure to obtain a one-component moisture-curable urethane composition that is the composition of the present embodiment.

  Thus, the composition of this embodiment contains an organic resin glass by containing a preliminary composition containing a urethane prepolymer, the compound (A), and an organic tin compound in the above-described range. Adhere resin glass adherends without applying surface treatment to adherents with poor adhesion such as highly solid paints, acid rain resistant paints, and easy-to-adhere paints that have been painted with easy maintenance paints. And can have excellent adhesion even after curing at room temperature.

  In other words, due to recent technological innovation, optimization of materials, etc., simplification and shortening of the manufacturing process, etc., the properties required for a one-component moisture-curing urethane composition are being advanced, and the conventional one-component No moisture curable urethane composition satisfies the above-mentioned high adhesion level without forming a primer on the hardly adherent adherend as described above, and further improves the adhesion to various adherends. Is required. In this regard, the composition of the present embodiment has excellent adhesiveness even if a primer is not formed on an adherend that is difficult to adhere. For this reason, the composition of the embodiment can be used as an adhesive for adhering to automobile paint and glass, and can adhere a window glass to a vehicle without using a primer, and exhibits a stable and strong adhesive force. It can be used as an adhesive.

  The composition, the application conditions, and the like of the present embodiment are not particularly limited. However, since the composition has excellent characteristics as described above, the composition of the automobile such as an adhesive used for bonding the vehicle body and the window glass is used. In addition to the field, it is suitably used as an adhesive for so-called hard-to-adhere coating plates coated with high solid paint, acid rain-resistant paint, easy maintenance paint, and the like.

  Hereinafter, the composition of the present embodiment will be specifically described by way of examples. However, this embodiment is not limited to these.

<Synthesis of urethane prepolymer>
750 g of polyoxypropylene triol (trade name: Exenol 5030, number average molecular weight of about 5000, manufactured by Asahi Glass Co., Ltd.), which is a polyether triol, and polyoxypropylene diol (trade name: Exenol 2020, number of about 2000), which is a polyether diol. , Manufactured by Asahi Glass Co., Ltd.) at a mass ratio of 70/30, the mixture was dehydrated at 120 ° C. under reduced pressure, and then melted 4,4′-diphenylmethane diisocyanate (trade name: Isonate 125M, manufactured by Mitsui Takeda Urethane Co., Ltd.) 4 The amount of NCO group of 4,4'-diphenylmethane diisocyanate and the OH group of the above mixture was 1.7 so that the urethane prepolymer was obtained after mixing and stirring at 80 ° C. for 24 hours during nitrogen substitution. The NCO group content of the obtained urethane prepolymer was 1.1% by mass in the total amount of the urethane prepolymer.

<Preparation of preliminary composition>
The urethane prepolymer thus obtained was added with plasticizer, carbon black, calcium carbonate, and morpholine catalyst in the amounts shown in Table 1 and mixed under vacuum for 1 hour using a mixer to prepare a preliminary composition. Obtained.

<Synthesis of adhesion promoter A>
While stirring 100 g of a biuret body of HDI (trade name: D165N, NCO group: 23.4% by mass, manufactured by Takeda Pharmaceutical Co., Ltd.), the NCO group / NH group was 3/1 in an N ₂ gas stream. Adhesion-imparting agent A (average molecular weight: 720, NCO group: 12) by reacting 26 g of (N-phenyl) aminopropyltrimethoxysilane (trade name: Y9669, manufactured by Nihon Unicar Co., Ltd.) while being dropped onto a biuret body of HDI. 0.1% by mass).
<Synthesis of adhesion imparting agents B to D>
Similar to the adhesion-imparting agent A, HDI biuret and 3- (N-phenyl) aminopropyltrimethoxysilane were mixed with NCO groups / NH groups of 1.5 / 1.0, 6.0 / 1.0. The adhesion imparting agents B to D were synthesized so as to be 9.0 / 1.0.

<Production of one-component moisture-curing urethane composition>
Each component shown in Table 1 was blended in the addition amount (part by mass) shown in the same table, and these were uniformly mixed to prepare each one-component moisture-curable urethane composition shown in Table 1. Table 1 shows the addition amount (parts by mass) of each component in each Example and Comparative Example.

<Evaluation>
The adhesiveness and foaming resistance of each obtained one-component moisture-curable urethane composition were evaluated according to the following methods. The results are shown in Table 1.

<Adhesiveness to difficult-to-adhere substrates>
A one-part moisture-curing urethane composition was directly applied to a resin glass coated with a siloxane resin at a thickness of 3 mm without using a primer to prepare a test specimen. This specimen was allowed to stand for 168 hours in an atmosphere of 20 ° C. ± 2 ° C. and 60 RH% ± 10 RH%. One end of the cured product of the one-part moisture-curing urethane composition formed on the test body was held and peeled 180 degrees, and the fracture state was observed. The cohesive failure of the cured product is CF (the numerical value is the area (%) where the cohesive failure of the cured product occurs relative to the area of the part where the cured product is peeled), and the interface peeling between the coated plate / cured product is AF (the numerical value The area (%) where interfacial peeling between the coated plate / cured product occurred relative to the area of the part from which the cured product was peeled. The results are shown in Table 1.

<Foaming resistance>
The state of the internal void | hole after peeling the hardened | cured material of the one-component moisture hardening type urethane composition apply | coated to resin glass was observed. When the one-component moisture-curing urethane composition is cured, CO ₂ is generated by the reaction, but there is a possibility that voids are formed inside the cured product due to CO ₂ . The more voids are inside the cured product, the more the cured product does not have a sufficient adhesion area with respect to the resin glass, so the adhesive strength decreases. The results are shown in Table 1.

Each component shown in Table 1 is as follows.
・ Plasticizer: Diisononyl phthalate (DINP), manufactured by Mitsubishi Chemical Corporation ・ Carbon black: Elf Tech 8, manufactured by Cabot Corporation ・ Calcium carbonate: Heavy calcium carbonate, trade name “SB Blue”, manufactured by Shiraishi Calcium ・ Morpholine catalyst : U-CAT 660M, manufactured by San Apro, organotin catalyst: Neostan U-810, manufactured by Nitto Kasei Kogyo Co., Ltd., organic bismuth catalyst: Neostan U-600, manufactured by Nitto Kasei Kogyo Co., Ltd.

As is clear from the results shown in Table 1, the cured products of the one-part moisture-curable urethane compositions of Examples 1 to 9 all exhibit cohesive failure (CF) with respect to the resin glass coated with the siloxane resin, and are high. It had adhesiveness. In addition, bubbles due to CO ₂ generated during curing were not observed inside the cured product, and the foam resistance was good. On the other hand, the cured products of the one-component moisture-curing urethane compositions of Comparative Examples 1 to 4 all show interfacial fracture (AF) with respect to the resin glass coated with the siloxane resin, or the cured product is cured when cured. Bubbles due to the generated CO ₂ were observed. Therefore, the cured products of the one-component moisture-curable urethane compositions of Comparative Examples 1 to 4 have insufficient adhesion to the resin glass coated with the siloxane resin or poor foam resistance.

  Therefore, a composition containing a specific amount of a specific adhesion-imparting agent A and an organotin compound in a urethane prepolymer adheres a glass adherend without subjecting the difficult-to-adhere adherend to a ground treatment. It has been found that it has excellent adhesion even after curing at room temperature.

  As mentioned above, the polyurethane adhesive composition for resin glass of this invention is excellent in adhesiveness with glass, a metal, a plastics, a coated steel plate etc., without using a primer. Therefore, the polyurethane adhesive composition for resin glass according to the present invention is applied with an adhesive used for bonding a vehicle body and a window glass, a high solid paint, an acid rain-resistant paint, an easy-maintenance paint, etc. It is very useful as an adhesive.

Claims (1)

A mixture of a polyether triol having a number average molecular weight of 1000 or more and 7000 or less and polyether diol is reacted with 4,4′-diphenylmethane diisocyanate within an equivalent ratio of isocyanate group to hydroxyl group of 1.1 or more and 2.5 or less. A pre-composition comprising a urethane prepolymer obtained by
The equivalent ratio of 3- (N-phenyl) aminopropyltrimethoxysilane and hexamethylene diisocyanate biuret is between 1.5 / 1.0 and 9.0 / 1.0. An adhesion-imparting agent A obtained by adding
An organic tin compound,
The content of the adhesion-imparting agent A is 2 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the urethane prepolymer,
Content of the said organic tin compound is 0.001 mass part or more and 0.5 mass part or less with respect to 100 mass parts of said urethane prepolymers, The polyurethane adhesive composition for resin glass characterized by the above-mentioned.