JP2013014664A - Multilayer adhesive article and adhesive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer adhesive article with a higher interlayer adhesive strength.SOLUTION: The multilayer adhesive article is provided with: an adhesive layer (A) formed from an adhesive composition (a) containing, as the main component, an acrylic polymer (a); an adhesive layer (B) formed from an adhesive composition (b) that contains, as the main component, an acrylic polymer (b); and an intermediate layer (C) that is positioned between the adhesive layer (A) and the adhesive layer (B). The adhesive composition (a) and the adhesive composition (b) each further contain a compound having two or more functional groups capable of reacting with active hydrogen in a molecule. The intermediate layer (C) is formed from an intermediate layer composition (c) that contains a polymer (c) obtained by polymerizing a monomer composition (c) that includes a monomer containing active hydrogen.

Description

  The present invention relates to a multilayer adhesive article and an adhesive sheet in which the multilayer adhesive article is formed into a sheet shape.

  Conventionally, pressure-sensitive adhesive tapes such as double-sided adhesive tapes have been required to have contradictory properties such as high wettability, adhesion, and high cohesive force with respect to an adherend. Furthermore, when bonding to two types of adherends having different surface characteristics, it is difficult to exert good adhesive properties on both of the adherends with a pressure-sensitive adhesive having the same composition, In many cases, it is processed in a form that balances characteristics between the two.

  In order to improve such points, by using two or more pressure-sensitive adhesives having different compositions to form a multilayer structure, adhesion to different adherends and supports, anchoring properties can be improved, Attempts have been made to control the properties by changing the composition and physical properties of the surface layer that requires strong bonding with the body and the inner layer that requires high cohesion.

  For example, Patent Document 1 discloses a pressure-sensitive adhesive tape having an adhesive layer having a multilayer structure composed of two or more compositions having different shear creep compliances. It is said to be particularly useful for diaper tapes and cloth display labels that are surface and are subject to various external stresses during use.

  However, the pressure-sensitive adhesive tape having the adhesive layer having a multilayer structure as described above has a drawback that the bonding force between the layers is weak and the layers are easily peeled off by an external stress such as a shearing force.

  In order to solve such a problem, it is composed of a plurality of superimposed layers, at least one outer layer is a pressure-sensitive adhesive layer, adjacent layers form an interface between the adjacent layers, and each of the layers Consists of a photopolymerized polymer chain matrix, which extends from one matrix of these layers through this interface into the matrix of the adjacent layer, which polymer chains are connected to each adjacent layer before polymerization. There has been proposed a pressure-sensitive adhesive tape composed of polymerized monomers that have migrated from the matrix, and the layers cannot cause delamination (see Patent Document 2).

  Also, after laminating at least two types of adhesive layers obtained by photopolymerizing a composition containing a (meth) acrylic acid alkyl ester and a photopolymerization initiator so that the compositions differ between adjacent layers, the adjacent layers The reactive functional group introduced into the molecule of the (meth) acrylic acid alkyl ester polymer that constitutes one layer of the layer, and the reactive functional group introduced into the molecule of the (meth) acrylic acid alkyl ester polymer that constitutes the other layer. A method for producing a pressure-sensitive adhesive tape in which adjacent layers are chemically bonded to each other by reaction with a functional group containing active hydrogen has been proposed (see Patent Document 3).

JP 54-139946 A Japanese Patent Publication No.2-6790 JP-A-5-105851

  However, a pressure-sensitive adhesive tape having a higher interlayer adhesion than the pressure-sensitive adhesive tapes described in Patent Documents 1 to 3 is required.

  An object of the present invention is to provide a multilayer adhesive article having a higher interlayer adhesion.

  The present inventor has intensively studied to solve the above problems. As a result, a monomer composition containing a monomer containing active hydrogen was polymerized between two adhesive layers each containing a compound having two or more functional groups capable of reacting with active hydrogen. By forming an intermediate layer from a composition containing a polymer to produce a multi-layered adhesive article, it was found that higher interlayer adhesion was developed, and the present invention was completed.

  That is, the multilayer adhesive article according to the present invention comprises an adhesive layer (A) formed from an adhesive composition (a) containing an acrylic polymer (a) as a main component, and an acrylic polymer (b). ) As a main component, a pressure-sensitive adhesive layer (B) formed from the pressure-sensitive adhesive composition (b), and an intermediate layer disposed between the pressure-sensitive adhesive layer (A) and the pressure-sensitive adhesive layer (B) (C), wherein the pressure-sensitive adhesive composition (a) and the pressure-sensitive adhesive composition (b) each further contain a compound having two or more functional groups capable of reacting with active hydrogen in the molecule, and the intermediate layer (C) is characterized in that it is formed from an intermediate layer composition (c) containing a polymer (c) obtained by polymerizing a monomer composition (c) containing a monomer containing active hydrogen. .

  In the multilayer adhesive article according to the present invention, the monomer containing active hydrogen is a monomer containing one or more functional groups selected from the group consisting of a carboxyl group, a hydroxyl group, and an amino group. Is preferred.

  In the multilayer pressure-sensitive adhesive article according to the present invention, the acrylic polymer (a) is obtained by polymerizing the monomer composition (a), and the acrylic polymer (b) is a monomer composition. The monomer composition (c) obtained by polymerizing (b) comprises a main component monomer of the monomer composition (a) and a main component of the monomer composition (b). It is preferable to contain a monomer.

  In the multilayer pressure-sensitive adhesive article according to the present invention, the monomer composition (c) includes all the monomers contained in the monomer composition (a) and the monomer composition (b). It is preferable that all the monomers contained are included.

  In the multilayer pressure-sensitive adhesive article according to the present invention, the compound having two or more functional groups capable of reacting with active hydrogen contained in the pressure-sensitive adhesive composition (a) and the pressure-sensitive adhesive composition (b) is contained in a large amount. A functional isocyanate compound is preferred.

  In the multilayer adhesive article according to the present invention, the monomer containing active hydrogen is preferably a monomer containing a hydroxyl group.

  In the multilayer adhesive article according to the present invention, it is preferable that the monomer containing active hydrogen is a monomer containing an amino group.

  In the multilayer adhesive article according to the present invention, the intermediate layer (C) includes a polymer (ca) obtained by polymerizing the monomer composition (ca), and a monomer composition (cb). 1) or more selected from the group consisting of polymers (c-b) obtained by polymerizing a polymer)), and the monomer composition (ca) comprises the monomer containing active hydrogen and The monomer composition (a) is a main component monomer, and the monomer composition (cb) includes the monomer containing active hydrogen and the monomer composition. The main component monomer (b) is preferably included.

  In the multilayer adhesive article according to the present invention, at least one selected from the group consisting of the acrylic polymer (a) and the acrylic polymer (b) contains an acid group, and the polymer ( c) preferably contains a primary to tertiary amino group.

  In the multilayer adhesive article according to the present invention, at least one selected from the group consisting of the acrylic polymer (a) and the acrylic polymer (b) contains an acid group, and the polymer ( It is preferable that at least one selected from the group consisting of c), the polymer (ca) and the polymer (cb) contains a primary to tertiary amino group.

  The pressure-sensitive adhesive sheet according to the present invention is characterized in that the multilayer pressure-sensitive adhesive article according to the present invention described above is provided as a pressure-sensitive adhesive layer.

  Since the multilayer adhesive article which concerns on this invention has the structure mentioned above, the multilayer adhesive article with a higher interlayer adhesive force can be provided. In particular, it is possible to provide a multilayer adhesive article that can suppress peeling between layers during peeling or the like.

  Hereinafter, the present invention will be specifically described.

  In the present specification, “A to B” indicating a range means that the range is A or more and B or less, and various physical properties mentioned in the present specification are in Examples described later unless otherwise specified. The value measured by the described method is meant. In the present specification, “(meth) acryl” in “(meth) acrylic acid” and the like means “acryl and / or methacryl”.

  In addition, the “main component” in the present specification means a component having the highest content ratio on a weight basis in the composition.

(I) Multilayer adhesive article A multilayer adhesive article according to the present invention comprises an adhesive layer (A) formed from an adhesive composition (a) containing an acrylic polymer (a) as a main component, and an acrylic. Between the pressure-sensitive adhesive layer (B) formed from the pressure-sensitive adhesive composition (b) containing the polymer (b) as a main component, and between the pressure-sensitive adhesive layer (A) and the pressure-sensitive adhesive layer (B). The pressure-sensitive adhesive composition (a) and the pressure-sensitive adhesive composition (b) each further contain a compound having two or more functional groups capable of reacting with active hydrogen in the molecule. The intermediate layer (C) was formed from an intermediate layer composition (c) containing a polymer (c) obtained by polymerizing a monomer composition (c) containing a monomer containing active hydrogen. Is.

  According to the said structure, the polymer (c) containing an active hydrogen in an intermediate | middle layer (C) molecule | numerates the functional group which can react with the active hydrogen in an adhesive layer (A) and an adhesive layer (B). It is considered that the interlaminar adhesive strength is increased because it has a covalent bond or interacts with a compound having two or more compounds (hereinafter, sometimes referred to as “active hydrogen-reactive polyfunctional compound”). Moreover, in the said structure, since it can produce also by superposition | polymerization methods other than photopolymerization, there are few restrictions on manufacture.

  In general, the production method of an acrylic polymer by photopolymerization such as UV polymerization is slower in production rate than solvent-based and emulsion-based methods, and does not polymerize unless it is blocked from air. It is necessary to be shielded from the air, and there are limitations such as high costs in these respects.

(I) Adhesive layer (A)
The pressure-sensitive adhesive layer (A) can be formed from a pressure-sensitive adhesive composition (a) containing the acrylic polymer (a) as a main component.

[Acrylic polymer (a)]
The acrylic polymer (a) can be obtained by polymerizing the monomer composition (a) containing (meth) acrylic acid alkyl ester as a main component. In addition, you may make the said monomer composition (a) contain the unsaturated monomer copolymerizable with the (meth) acrylic-acid alkylester if desired.

  Examples of the (meth) acrylic acid alkyl ester include (meth) acrylic acid alkyl esters having 1 to 18 carbon atoms in the alkyl group, and specifically, a compound represented by the following general formula (1): Can be mentioned.

(In general formula (1), R ¹ represents a hydrogen atom or a methyl group, and R ² represents a linear or branched alkyl group having 1 to 18 carbon atoms.)
Specific examples of R ² in the general formula (1) include, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl group, neopentyl group, Isoamyl group, hexyl group, heptyl group, octyl group, 2-ethylhexyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, A hexadecyl group, a heptadecyl group, an octadecyl group, etc. are mentioned.

  Specific examples of the (meth) acrylic acid alkyl ester represented by the general formula (1) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and (meth) acrylic acid. Isopropyl, butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, neopentyl (meth) acrylate, (meth ) Isoamyl acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, (meth) acrylic acid Nonyl, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate Undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, Examples include (meth) acrylate octadecyl. These alkyl (meth) acrylates may be used alone or in combination of two or more.

  As for carbon number of the alkyl group in the said (meth) acrylic-acid alkylester, it is more preferable that it is 2-18, and it is still more preferable that it is 4-12.

  The blending ratio of the above-mentioned (meth) acrylic acid alkyl ester is, for example, 60 to 99.5 parts by weight, preferably 70 to 99 parts by weight with respect to 100 parts by weight of the total amount of the monomer composition (a). can do.

  Examples of the unsaturated monomer include functional group-containing unsaturated monomers, such as carboxyl group-containing unsaturated monomers, sulfonic acid group-containing unsaturated monomers, and phosphate group-containing unsaturated monomers. Examples include monomers containing acidic groups such as monomers.

  Examples of the carboxyl group-containing unsaturated monomer include unsaturated carboxylic acids such as (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, cinnamic acid; monomethyl itaconate, monobutyl itaconate, 2-acryloyl Unsaturated dicarboxylic acid monoesters such as oxyethylphthalic acid; Unsaturated tricarboxylic acid monoesters such as 2-methacryloyloxyethyl trimellitic acid and 2-methacryloyloxyethyl pyromellitic acid; Carboxyethyl acrylate (β-carboxyethyl acrylate, etc.) Carboxyalkyl acrylates such as carboxypentyl acrylate; acrylic acid dimers, acrylic acid trimers; unsaturated dicarboxylic acid anhydrides such as itaconic anhydride, maleic anhydride, and fumaric anhydride.

  Examples of the sulfonic acid group-containing unsaturated monomer include styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, And (meth) acryloyloxynaphthalenesulfonic acid.

  Examples of the phosphate group-containing unsaturated monomer include 2-hydroxyethyl acryloyl phosphate.

  Examples of the functional group-containing unsaturated monomer other than the acidic group-containing monomer include hydroxyl group-containing unsaturated monomers such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 4-hydroxybutyl acrylate. Monomer; (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methoxymethyl ( Amide group-containing unsaturated monomers such as (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (meth) acrylamide; aminoethyl (meth) acrylate, N, N-dimethylamino (meth) acrylate Amino group-containing substances such as ethyl and t-butylaminoethyl (meth) acrylate Sum monomers; glycidyl group-containing unsaturated monomers such as glycidyl (meth) acrylate and methyl glycidyl (meth) acrylate; cyano group-containing unsaturated monomers such as (meth) acrylonitrile; N-cyclohexylmaleimide; Maleimide group-containing monomers such as N-isopropylmaleimide, N-laurylmaleimide, N-phenylmaleimide; N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide, N-2 -Itaconimide group-containing monomers such as ethylhexylitaconimide, N-cyclohexylitaconimide, N-laurylitaconimide; N- (meth) acryloyloxymethylenesuccinimide, N- (meth) acryloyl-6-oxyhexamethylenesuccinimide, N -(Meta) a Succinimide group-containing monomers such as liloyl-8-oxyoctamethylenesuccinimide; N-vinylpyrrolidone, N- (1-methylvinyl) pyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine , N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-vinylmorpholine, vinyl group-containing heterocyclic compounds such as (meth) acryloylmorpholine; and functionality such as 2-methacryloyloxyethyl isocyanate Monomers, other N-vinylcarboxylic acid amides and the like.

  The blending ratio of the functional group-containing unsaturated monomer is, for example, 0.5 to 12 parts by weight, preferably 1 to 10 parts by weight with respect to 100 parts by weight of the total amount of the monomer composition (a). It is.

  Examples of other unsaturated monomers include vinyl ester group-containing monomers such as vinyl acetate; aromatic unsaturated monomers such as styrene and vinyl toluene; cyclopentyl di (meth) acrylate, isobornyl (meta ) (Meth) acrylic acid alicyclic hydrocarbon ester monomers such as acrylate; alkoxy group-containing unsaturated monomers such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; ethylene, propylene, isoprene Olefin monomers such as butadiene, isobutylene; vinyl ether monomers such as vinyl ether; halogen atom-containing unsaturated monomers such as vinyl chloride; and others such as tetrahydrofurfuryl (meth) acrylate and fluorine ( Acrylic ester-based monomer containing a heterocycle such as (meth) acrylate or a halogen atom Etc. The.

  The monomer composition (a) may further contain a polyfunctional monomer. Examples of the polyfunctional monomer include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and tetraethylene glycol di (meth) acrylate. (Mono or poly) ethylene glycol di (meth) acrylate such as acrylate; (mono or poly) alkylene glycol di (meth) such as (mono or poly) propylene glycol di (meth) acrylate such as propylene glycol di (meth) acrylate ) Acrylate; neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tetramethylolmethane tri (meth) acrylate, pentaerythritol di (meth) acrylate And (meth) acrylic acid esters of polyhydric alcohols such as trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate and dipentaerythritol hexa (meth) acrylate; divinylbenzene and the like. Moreover, epoxy acrylate, polyester acrylate, urethane acrylate, etc. are mentioned as a polyfunctional monomer.

  The monomer composition (a) may further contain an alkoxysilyl group-containing vinyl monomer. Examples of the alkoxysilyl group-containing vinyl monomer include silicone (meth) acrylate monomers and silicone vinyl monomers.

  Examples of the silicone-based (meth) acrylate monomer include (meth) acryloyloxymethyl-trimethoxysilane, (meth) acryloyloxymethyl-triethoxysilane, 2- (meth) acryloyloxyethyl-trimethoxysilane, 2 -(Meth) acryloyloxyethyl-triethoxysilane, 3- (meth) acryloyloxypropyl-trimethoxysilane, 3- (meth) acryloyloxypropyl-triethoxysilane, 3- (meth) acryloyloxypropyl-tripropoxysilane , (Meth) acryloyloxyalkyl-trialkoxysilane such as 3- (meth) acryloyloxypropyl-triisopropoxysilane, 3- (meth) acryloyloxypropyl-tributoxysilane, for example, (meth) a Liloyloxymethyl-methyldimethoxysilane, (meth) acryloyloxymethyl-methyldiethoxysilane, 2- (meth) acryloyloxyethyl-methyldimethoxysilane, 2- (meth) acryloyloxyethyl-methyldiethoxysilane, 3- (Meth) acryloyloxypropyl-methyldimethoxysilane, 3- (meth) acryloyloxypropyl-methyldiethoxysilane, 3- (meth) acryloyloxypropyl-methyldipropoxysilane, 3- (meth) acryloyloxypropyl-methyldi Isopropoxysilane, 3- (meth) acryloyloxypropyl-methyldibutoxysilane, 3- (meth) acryloyloxypropyl-ethyldimethoxysilane, 3- (meth) acryloyloxypropyl-ethyl Diethoxysilane, 3- (meth) acryloyloxypropyl-ethyldipropoxysilane, 3- (meth) acryloyloxypropyl-ethyldiisopropoxysilane, 3- (meth) acryloyloxypropyl-ethyldibutoxysilane, 3- ( (Meth) acryloyloxypropyl-propyldimethoxysilane, (meth) acryloyloxyalkyl-alkyldialkoxysilane such as 3- (meth) acryloyloxypropyl-propyldiethoxysilane, and (meth) acryloyloxyalkyl-dialkyl corresponding to these (Mono) alkoxysilane etc. are mentioned.

  In addition, examples of silicone-based vinyl monomers include vinyltrialkoxysilanes such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinyltriisopropoxysilane, and vinyltributoxysilane. Vinylalkyldialkoxysilanes and vinyldialkylalkoxysilanes such as vinylmethyltrimethoxysilane, vinylmethyltriethoxysilane, β-vinylethyltrimethoxysilane, β-vinylethyltriethoxysilane, γ-vinylpropyltrimethoxysilane , Γ-vinylpropyltriethoxysilane, γ-vinylpropyltripropoxysilane, γ-vinylpropyltriisopropoxysilane, γ-vinylpropyltributoxysilane, etc. Other Kokishishiran, these correspond and (vinyl) alkyl dialkoxy silanes include (vinyl alkyl) dialkyl (mono) alkoxysilanes.

  By using an alkoxysilyl group-containing vinyl monomer, an alkoxysilyl group is introduced into the polymer chain, and a crosslinked structure can be formed by a reaction between the silyl groups. These alkoxysilyl group-containing vinyl monomers are suitably used alone or in combination.

  The blending ratio of these alkoxysilyl group-containing vinyl monomers is, for example, in the range of higher than 0 parts by weight and lower than 40 parts by weight, preferably higher than 0 parts by weight with respect to 100 parts by weight of the (meth) acrylic acid alkyl ester. Within the range of 30 parts by weight or less.

  The acrylic polymer (a) can be prepared by polymerizing the monomer composition (a) by a known or conventional polymerization method. Examples of the polymerization method of the acrylic polymer (a) include a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, and a polymerization method by active energy ray irradiation (active energy ray polymerization method). Among them, the solution polymerization method and the active energy ray polymerization method are preferable in terms of transparency, water resistance, cost, and the like, and the solution polymerization method is more preferable.

  In the polymerization of the acrylic polymer (a), various common solvents can be used. Examples of the solvent include esters such as ethyl acetate and n-butyl acetate; aromatic hydrocarbons such as toluene and benzene; aliphatic hydrocarbons such as n-hexane and n-heptane; cyclohexane and methylcyclohexane Organic solvents such as ketones such as methyl ethyl ketone and methyl isobutyl ketone. A solvent can be used individually or in combination of 2 or more types.

  In the polymerization of the acrylic polymer (a), a polymerization initiator such as a thermal polymerization initiator or a photopolymerization initiator (photoinitiator) can be used depending on the type of polymerization reaction. In addition, a polymerization initiator can be used individually or in combination of 2 or more types.

  Examples of the thermal polymerization initiator include azo-based initiators, peroxide-based polymerization initiators (eg, dibenzoyl peroxide, tert-butyl permaleate), redox-based polymerization initiators, and the like. Of these, the azo initiators disclosed in JP-A No. 2002-69411 are particularly preferable. Such an azo-based initiator is preferable because a decomposition product of the initiator hardly remains in the acrylic polymer (a) as a part that causes generation of a heat generation gas (outgas). Examples of the azo initiator include 2,2′-azobisisobutyronitrile (AIBN), 2,2′-azobis-2-methylbutyronitrile (AMBN), 2,2′-azobis (2 -Methylpropionic acid) dimethyl, 4,4'-azobis-4-cyanovaleric acid and the like. The amount of the azo initiator used is preferably 0.05 to 0.5 parts by weight with respect to 100 parts by weight in total of the monomer composition (a) constituting the acrylic polymer (a). Preferably it is 0.1-0.3 weight part.

  The acrylic polymer (a) obtained as described above is contained as a main component in the pressure-sensitive adhesive layer (A), preferably 50% by weight or more, and preferably 60% by weight or more. It is more preferable that it is contained, more preferably 70% by weight or more, and particularly preferably 80% by weight or more.

  The weight average molecular weight (Mw) of the acrylic polymer (a) is, for example, 100,000 to 3,000,000, preferably 250,000 to 1,500,000, more preferably 500,000 to 1,100,000. By setting the weight average molecular weight of the acrylic polymer (a) to 100,000 or more, the cohesive force and heat resistance are improved. On the other hand, the viscosity at the time of setting it as a solution can be made low by making the weight average molecular weight of an acrylic polymer (a) into 3 million or less.

The weight average molecular weight of the acrylic polymer (a) can be measured by a gel permeation chromatograph (GPC) method. More specifically, for example, as a GPC measuring apparatus, using the trade name “HLC-8120GPC” (manufactured by Tosoh Corporation), the following conditions: Sample concentration: about 2.0 g / L (tetrahydrofuran solution)
Sample injection volume: 20 μL
Column: Trade name “TSKgel, SuperAWM-H + superAW4000 + superAW2500” (manufactured by Tosoh Corporation)
Column size: 6.0 mmI. D. × 150mm
・ Eluent: Tetrahydrofuran (THF)
・ Flow rate: 0.4mL / min
・ Detector: Differential refractometer (RI)
Column temperature (measurement temperature): 40 ° C
And can be calculated by standard polystyrene conversion value.

[Active hydrogen reactive polyfunctional compound]
The pressure-sensitive adhesive composition (a) further contains an active hydrogen-reactive polyfunctional compound. The active hydrogen-reactive polyfunctional compound is not particularly limited as long as it has two or more functional groups capable of reacting with active hydrogen in the molecule, and examples thereof include polyfunctional isocyanate compounds and polyfunctional epoxy compounds. .

  The content of the active hydrogen-reactive polyfunctional compound is not particularly limited, but is preferably 0.01 to 50 parts by weight with respect to 100 parts by weight of the acrylic polymer (a). More preferably, it is 1 part by weight, and still more preferably 1-15 parts by weight.

  As the polyfunctional isocyanate compound, for example, lower aliphatic polyisocyanates such as 1,2-ethylene diisocyanate, 1,4-butylene diisocyanate, 1,6-hexamethylene diisocyanate; cyclopentylene diisocyanate, cyclohexylene diisocyanate, isophorone diisocyanate , Cycloaliphatic polyisocyanates such as hydrogenated tolylene diisocyanate and hydrogenated xylene diisocyanate; aromas such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate Group polyisocyanate etc. are mentioned, These may be used independently and may use 2 or more types together. Examples of the isocyanate-based crosslinking agent include trimethylolpropane / tolylene diisocyanate adduct [manufactured by Nippon Polyurethane Industry Co., Ltd., trade name “Coronate L”], trimethylolpropane / hexamethylene diisocyanate adduct [Nippon Polyurethane. Commercial products such as Kogyo Co., Ltd., trade name “Coronate HL”, trimethylolpropane / xylylene diisocyanate adduct [Mitsui Chemicals, trade name “Takenate D-110N”] can also be used.

  Examples of the polyfunctional epoxy compound include N, N, N ′, N′-tetraglycidyl-m-xylenediamine, diglycidylaniline, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, , 6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, Pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, trimethylolpropane poly In addition to lysidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris (2-hydroxyethyl) isocyanurate, resorcin diglycidyl ether, bisphenol-S-diglycidyl ether, epoxy in the molecule Examples thereof include an epoxy resin having two or more groups, and these may be used alone or in combination of two or more. Moreover, as said epoxy type crosslinking agent, commercial items, such as Mitsubishi Gas Chemical Co., Ltd. make and brand name "Tetrad C", can also be used, for example.

[Other ingredients]
The pressure-sensitive adhesive composition (a) may include other cross-linking agents, cross-linking accelerators, silane coupling agents, tackifying resins (rosin derivatives, polyterpene resins, petroleum resins, oil-soluble phenols, etc.), aging as necessary. Known additives such as inhibitors, fillers, colorants (pigments, dyes, etc.), ultraviolet absorbers, antioxidants, chain transfer agents, plasticizers, softeners, surfactants, antistatic agents, etc. It can be used within a range that does not impair the characteristics.

  Moreover, when forming an adhesive layer (A), various common solvents can also be used. The type of such a solvent is not particularly limited, and those exemplified as the solvent used in the above solution polymerization can be used.

  Examples of the crosslinking agent include a melamine crosslinking agent and a peroxide crosslinking agent, a urea crosslinking agent, a metal alkoxide crosslinking agent, a metal chelate crosslinking agent, a metal salt crosslinking agent, a carbodiimide crosslinking agent, and an oxazoline crosslinking agent. A crosslinking agent, an aziridine type crosslinking agent, an amine type crosslinking agent, etc. are mentioned. In addition, a crosslinking agent can be used individually or in combination of 2 or more types.

(II) Adhesive layer (B)
The pressure-sensitive adhesive layer (B) can be formed from a pressure-sensitive adhesive composition (b) containing the acrylic polymer (b) as a main component and the acrylic polymer (b) as a main component. The acrylic polymer (b) is obtained by polymerizing the monomer composition (b). Like the pressure-sensitive adhesive composition (a), the pressure-sensitive adhesive composition (b) is active hydrogen reactive. Contains polyfunctional compounds.

  The pressure-sensitive adhesive layer (B) may be the same composition as the pressure-sensitive adhesive layer (A) or may have a different composition, but the viewpoint of exhibiting good adhesive properties to two different adherends Therefore, it is preferable to have different compositions, and more specifically, it is preferable to use different adhesive layers each exhibiting high adhesive strength to each adherend.

  In addition, an adhesive layer (B) can be comprised within the range mentioned above about the adhesive layer (A) similarly to an adhesive layer (A), and can be produced by the same method. As a matter of course, the monomer composition (b), the acrylic polymer (b), and the pressure-sensitive adhesive composition (b) also include the monomer composition (a), the acrylic polymer (a), and the pressure-sensitive adhesive composition (b). The pressure-sensitive adhesive composition (a) can be constituted within the above-described range, and can be produced by the same method.

(III) Intermediate layer (C)
The intermediate layer (C) is disposed between the pressure-sensitive adhesive layer (A) and the pressure-sensitive adhesive layer (B), and contains a monomer containing active hydrogen (hereinafter referred to as “active hydrogen-containing monomer”). It is formed from the intermediate | middle layer composition (c) containing the polymer (c) which polymerized the monomer composition (c) containing.

  Examples of the active hydrogen-containing monomer include monomers containing one or more functional groups selected from the group consisting of a carboxyl group, a hydroxyl group and an amino group, and are selected from the group consisting of a hydroxyl group and an amino group. Preferred are monomers containing one or more functional groups.

  Examples of the monomer containing a carboxyl group include the various carboxyl group-containing unsaturated monomers described above.

  Examples of the monomer containing a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 6- (meth) acrylic acid. Hydroxyl-containing (meth) acrylic acid esters such as hydroxyhexyl, hydroxyoctyl (meth) acrylate, hydroxydecyl (meth) acrylate, hydroxylauryl (meth) acrylate, (meth) acrylic acid (4-hydroxymethylcyclohexyl); Vinyl alcohol, allyl alcohol, etc. are mentioned, These may be used independently and may use 2 or more types together.

  Among these, as the hydroxyl group-containing monomer, a hydroxyl group-containing (meth) acrylic acid ester is preferable, and 2-hydroxyethyl acrylate and 4-hydroxybutyl acrylate are more preferable.

  Examples of the monomer containing an amino group include (meth) acrylamides and allylamines.

  Examples of the (meth) acrylamides include (meth) acrylamide, N-alkyl (meth) acrylamide and the like.

  Examples of the N-alkyl (meth) acrylamide include N-ethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, Nn-butyl (meth) acrylamide, N-octylacrylamide and the like. Furthermore, the N-alkyl (meth) acrylamide includes (meth) acrylamide having an amino group such as dimethylaminoethyl (meth) acrylamide, diethylaminoethyl (meth) acrylamide, and dimethylaminopropyl (meth) acrylamide.

  The (meth) acrylamides also include various N-hydroxyalkyl (meth) acrylamides, for example. Examples of the N-hydroxyalkyl (meth) acrylamide include N-methylol (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, N- (2-hydroxypropyl) (meth) acrylamide, N- (1-hydroxypropyl) (meth) acrylamide, N- (3-hydroxypropyl) (meth) acrylamide, N- (2-hydroxybutyl) (meth) acrylamide, N- (3-hydroxybutyl) (meth) acrylamide, N- (4-hydroxybutyl) (meth) acrylamide, N-methyl-N-2-hydroxyethyl (meth) acrylamide and the like can be mentioned.

  Examples of the allylamines include allylamine, allylalkylamine, allylalkoxyamine, diallylamine and the like.

  In addition, the said monomer containing an amino group may be used independently, and may use 2 or more types together.

  The content of the active hydrogen-containing monomer in the monomer composition (c) may be appropriately changed depending on the composition of the pressure-sensitive adhesive layers (A) and (B). For example, 0.001 to 100% by weight It is preferably 0.01 to 75% by weight, more preferably 0.1 to 50% by weight, still more preferably 1 to 25% by weight, and 5 to 20% by weight. It is particularly preferred. By setting the content of the active hydrogen-containing monomer in the monomer composition (c) within the above range, the interlayer adhesive force between the pressure-sensitive adhesive layers (A) and (B) and the intermediate layer (C) is More improved.

  When the acrylic polymer (a) and / or the acrylic polymer (b) contains an acid group such as a carboxyl group, a monomer composition containing a primary to tertiary amino group is used. It is preferable to further contain in (c). As a result, the adhesive strength between the pressure-sensitive adhesive layers (A) and (B) and the intermediate layer (C) is such that the acid-base interaction between the acrylic polymer (a) and / or (b) and the polymer (c). It is thought that it becomes higher by action. In addition, the above-mentioned “1-3 primary amino group” means “primary amino group, secondary amino group or tertiary amino group”.

  In this case, the content ratio of the primary to tertiary amino group-containing monomer in the monomer composition (c) is not particularly limited, but is preferably 0.1 to 25% by weight, More preferably, it is 5% by weight, and particularly preferably 5-15% by weight.

  The primary to tertiary amino group-containing monomer is not particularly limited, and examples thereof include N, N′-diethylaminomethyl (meth) acrylate, N, N′-dimethylaminomethyl (meth) acrylate, and N, N ′. -Dialkylaminoalkyl (meth) acrylates such as dimethylaminoethyl (meth) acrylate, N, N'-dimethylaminopropyl (meth) acrylate, N, N'-diethylaminoethyl (meth) acrylate, allyl dialkylamine, allyl di Examples include alkoxyamines and the amino group-containing monomers described above, and these may be used alone or in combination of two or more.

  As monomers that can be included in the monomer composition (c) other than the active hydrogen-containing monomer and the primary to tertiary amino group-containing monomer, polymerization of acrylic polymers (a) and (b) The above-mentioned various monomers that can be used for the monomer composition (c) are included, and the monomer composition (c) includes the main component monomer of the monomer composition (a) and the main component of the monomer composition (b). It is preferable to further contain a component monomer. With such a configuration, since the affinity of the intermediate layer (C) with respect to the pressure-sensitive adhesive layer (A) and the pressure-sensitive adhesive layer (B) is increased, it is considered that the interlayer adhesion is further increased.

  The content ratio of the main component monomer of the monomer composition (a) in the monomer composition (c) is not particularly limited, but is preferably 5 to 90% by weight, and 15 to 80% by weight. % Is more preferable, and 25 to 70% by weight is particularly preferable.

  Similarly, the content ratio of the main component monomer of the monomer composition (b) in the monomer composition (c) is not particularly limited, but is preferably 5 to 90% by weight, More preferably, it is -80 weight%, It is especially preferable that it is 25-70 weight%.

  The monomer composition (c) includes a monomer composition other than the main component monomer of the monomer composition (a) and the main component monomer of the monomer composition (b). A monomer other than the main component monomer contained in (a) or a monomer other than the main component monomer contained in the monomer composition (b) may be contained. It is preferable to contain all the monomers contained in the product (a) and the monomers contained in the monomer composition (b).

  By configuring the monomer composition (c) as described above, the affinity of the intermediate layer (C) with respect to the pressure-sensitive adhesive layer (A) and the pressure-sensitive adhesive layer (B) is increased, and the interlayer adhesion is increased. It will be higher.

  The content of the polymer (c) in the intermediate layer (C) is not particularly limited, but is preferably 2 to 50% by weight, more preferably 3 to 40% by weight, and 4 to 30% by weight. It is particularly preferred that By setting it within such a range, it is considered that the interlayer adhesive strength is further increased.

  Further, the intermediate layer (C) is a polymer (ca) obtained by polymerizing the monomer composition (ca) and / or a polymer obtained by polymerizing the monomer composition (cb). It is preferable to further contain (c-b).

  The content of the active hydrogen-containing monomer in each of the monomer compositions (ca) and (cb) is preferably independently 0.1 to 25% by weight, More preferably, the content is in the range of 5 to 15% by weight.

  Further, when the acrylic polymer (a) and / or the acrylic polymer (b) contains an acid group such as a carboxyl group, the above-mentioned primary to tertiary amino group-containing monomers are used as monomers. It is preferable to further include in the composition (ca) and / or the monomer composition (cb). Thereby, the correlation adhesive force of an adhesive layer (A) and an adhesive layer (B), and an intermediate | middle layer (C) is an acrylic polymer (a) and / or an acrylic polymer (b), and a polymer ( It is thought that it becomes higher by acid-base interaction with c-a) and / or polymer (c-b).

  In this case, the content ratios of the primary to tertiary amino group-containing monomers in the monomer compositions (ca) and (cb) are each independently 0.1 to 25% by weight. It is preferably 1 to 20% by weight, more preferably 5 to 15% by weight.

  As monomers that can be included in the monomer composition (ca) other than the active hydrogen-containing monomer and the primary to tertiary amino group-containing monomer, the polymerization of the acrylic polymer (a) is possible. The various monomers mentioned above which can be used are mentioned, It is preferable that the main component monomer of monomer composition (a) is further included.

  Further, the content ratio of the main component monomer of the monomer composition (a) in the monomer composition (ca) is not particularly limited, but is preferably 5 to 95% by weight, It is more preferably 15 to 90% by weight, and particularly preferably 25 to 85% by weight.

  Furthermore, in the monomer composition (ca), in addition to the main component monomer of the monomer composition (a), the main component monomer contained in the monomer composition (a) Other monomers may be included, and it is preferable to include all the monomers contained in the monomer composition (a).

  Similarly, monomers other than active hydrogen-containing monomers and primary to tertiary amino group-containing monomers that can be included in the monomer composition (c-b) include acrylic polymers (b). The above-mentioned various monomers that can be used for the polymerization are mentioned, and it is preferable that the main component monomer of the monomer composition (b) is further included.

  Further, the content ratio of the main component monomer of the monomer composition (b) in the monomer composition (cb) is not particularly limited, but is preferably 5 to 95% by weight, It is more preferably 15 to 90% by weight, and particularly preferably 25 to 85% by weight.

  Furthermore, in the monomer composition (cb), in addition to the main component monomer of the monomer composition (b), other than the main component monomer contained in the monomer composition (b). These monomers may be contained, and it is preferable to contain all the monomers contained in the monomer composition (b).

  The contents of the acrylic polymer (ca) and the acrylic polymer (cb) in the intermediate layer (C) are not particularly limited, but are independently 1 to 50% by weight. It is preferably 5 to 45% by weight, more preferably 10 to 40% by weight.

  The polymer (c), the polymer (ca), and the polymer (cb) are, as described above, the monomer composition as in the case of the acrylic polymer (a). (C), (ca), and (cb) can be prepared by polymerizing by a known or conventional polymerization method, respectively.

  In addition, the polymer (c), the polymer (ca), and the polymer (cb) each independently have a weight average molecular weight (Mw) of, for example, 100,000 to 3,000,000. , Preferably 250,000 to 1,500,000, more preferably 500,000 to 1,100,000. By setting the weight average molecular weight of these polymers to 100,000 or more, the cohesive force and heat resistance are improved. On the other hand, by setting the weight average molecular weight of these polymers to 3 million or less, the viscosity when made into a solution can be lowered.

  In addition, the weight average molecular weight of these polymers can be measured by the gel permeation chromatograph (GPC) method mentioned above similarly to the acrylic polymer (a).

  The intermediate layer composition (c) may contain other crosslinking agents, crosslinking accelerators, silane coupling agents, tackifying resins (rosin derivatives, polyterpene resins, petroleum resins, oil-soluble phenols, etc.) as necessary. , Known additives such as anti-aging agents, fillers, colorants (pigments, dyes, etc.), ultraviolet absorbers, antioxidants, chain transfer agents, plasticizers, softeners, surfactants, antistatic agents, It can be used as long as the characteristics of the present invention are not impaired.

  Moreover, when forming an intermediate | middle layer (C), various common solvents can also be used. The type of such a solvent is not particularly limited, and those exemplified as the solvent used in the above solution polymerization can be used.

(IV) Multilayer adhesive article The multilayer adhesive article according to the present invention can be produced by laminating the above-described layers by a conventionally known method.

  Although the manufacturing method of the multilayer adhesive article which concerns on this invention is not specifically limited, For example, (i) The said adhesive composition (a) is apply | coated (coating) on a base material or a peeling liner, and as needed. Drying and / or curing to form the pressure-sensitive adhesive layer (A), (ii) applying (coating) the intermediate layer composition (c) on the formed pressure-sensitive adhesive layer (A), and Accordingly, the intermediate layer (C) is formed by drying and / or curing, and (iii) the pressure-sensitive adhesive composition (b) is applied (coated) on the formed intermediate layer (C) and necessary. Accordingly, the substrate is dried and / or cured to form the pressure-sensitive adhesive layer (B), thereby forming the base material or the release liner / pressure-sensitive adhesive layer (A) / intermediate layer (C) / pressure-sensitive adhesive layer (B). A multilayer adhesive article having

  Further, as another method, (i) the pressure-sensitive adhesive composition (a) is applied (coated) on a base material or a release liner, and dried and / or cured as necessary, and a pressure-sensitive adhesive layer ( A) is formed, (ii) The pressure-sensitive adhesive composition (b) is applied (coated) on another base material or a release liner, and dried and / or cured as necessary, and a pressure-sensitive adhesive layer ( B) is formed. (Iii) The intermediate layer composition (c) is applied (coated) on the formed pressure-sensitive adhesive layers (A) and (B), respectively. (Iv) The coated surfaces are bonded to each other. Multilayer having the structure of substrate or release liner / adhesive layer (A) / intermediate layer (C) / adhesive layer (B) / substrate or release liner by forming an intermediate layer (C) by combining An adhesive article can be produced.

  In the said manufacturing method, it is preferable to perform an aging process after forming a multilayer adhesive article as mentioned above. As conditions of an aging process, the conditions for about 1 to 5 days are mentioned at the temperature range of 40-80 degreeC, for example.

  In addition, in the multilayer adhesive article which concerns on this invention, if the intermediate | middle layer (C) is arrange | positioned between the said adhesive layer (A) and the said adhesive layer (B), it will contain further another layer. It may be. For example, another layer such as a primer may be further provided between the base material or the release liner and the pressure-sensitive adhesive layer (B), and on the pressure-sensitive adhesive layer (A) (the intermediate layer (C) and Another layer such as a release liner may be further provided on the surface opposite to the surface in contact with the surface.

  Moreover, the structure of an adhesive layer is not limited to an adhesive layer (A) / intermediate layer (C) / adhesive layer (B), For example, an adhesive layer (B) / intermediate layer (C) / adhesion The composition of the adhesive layer (A) / intermediate layer (C) / adhesive layer (B) may be used, or the adhesive layer (B) / intermediate layer (C) / adhesive layer (A) / substrate / The structure of an adhesive layer (A) / intermediate layer (C) / adhesive layer (B) may be sufficient. By adopting such a structure, the composition and physical properties of the surface layer that requires a strong bond with the adherend and the inner layer that requires a high cohesive force can be changed, and the characteristics can be easily controlled. it can.

  For the application (coating) of the pressure-sensitive adhesive compositions (a) and (b) and the intermediate layer composition (c), a known coating method can be used, and a conventional coater, for example, Gravure roll coaters, reverse roll coaters, kiss roll coaters, dip roll coaters, bar coaters, knife coaters, spray coaters, comma coaters, direct coaters and the like can be used.

  Although the thickness of an adhesive layer (A) is not specifically limited, 0.1-500 micrometers is preferable, More preferably, it is 0.5-250 micrometers, More preferably, it is 1-200 micrometers.

  Although the thickness of an adhesive layer (B) is not specifically limited, 0.1-500 micrometers is preferable, More preferably, it is 1-250 micrometers, More preferably, it is 5-200 micrometers.

  The thickness of the intermediate layer (C) is not particularly limited, but is preferably 0.001 to 100 μm, more preferably 0.01 to 50 μm, still more preferably 0.05 to 10 μm, particularly preferably 0.05 to 5 μm, most preferably Preferably it is 0.05-1 micrometer.

  The multilayer pressure-sensitive adhesive article according to the present invention can provide a multilayer pressure-sensitive adhesive article having a higher interlayer adhesive force by the above-described configuration. Specifically, the multilayer pressure-sensitive adhesive article exhibits an interlayer adhesive force of 4.0 N / 20 mm or more. An adhesive article can be provided.

(V) Adhesive sheet The adhesive sheet which concerns on this invention is equipped with the multilayer adhesive article mentioned above as an adhesive layer. For example, it can be produced by forming a multilayer adhesive article into a sheet shape by the method described above.

  The pressure-sensitive adhesive sheet according to the present invention may be a pressure-sensitive adhesive sheet with a substrate having such a pressure-sensitive adhesive layer on one side or both sides of a sheet-like base material (support), and the pressure-sensitive adhesive layer is a release sheet (release surface). It may be a sheet-like base material provided with a base material-less pressure-sensitive adhesive sheet such as a form held on the base material. The concept of the pressure-sensitive adhesive sheet herein may include what are called pressure-sensitive adhesive tapes, pressure-sensitive adhesive labels, pressure-sensitive adhesive films and the like.

  In addition, in the adhesive sheet with a substrate in a form having both sides, an adhesive layer is provided on both sides of the substrate, but these adhesive layers may be formed of an adhesive having the same composition, or adhesives having different compositions. Each may be formed with an agent.

  The pressure-sensitive adhesive layer is typically formed continuously, but is not limited to such a form. For example, the pressure-sensitive adhesive layer is formed in a regular or random pattern such as a spot or stripe. It may be. The pressure-sensitive adhesive sheet provided by the present invention may be in the form of a roll or a single sheet. Or the adhesive sheet of the form processed into various shapes may be sufficient.

  Examples of the material for forming the base material include polyolefin films such as polyethylene, polypropylene, and ethylene / propylene copolymers; polyester films such as polyethylene terephthalate; plastic films such as polyvinyl chloride; paper such as kraft paper and Japanese paper Kinds: Cloths such as cotton cloth and soft cloth; woven cloths such as polyester non-woven cloth and vinylon cloth woven cloth; metal foil.

  The plastic films may be non-stretched films or stretched (uniaxially stretched or biaxially stretched) films. The surface of the substrate on which the pressure-sensitive adhesive layer is provided may be subjected to a surface treatment such as application of a primer and corona discharge treatment.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the following examples and comparative examples. In the following description, “parts” and “%” are based on weight unless otherwise specified.

[Example 1]
(Synthesis of acrylic polymer (a))
In a reactor equipped with a thermometer, a stirrer, a nitrogen introduction tube and a reflux condenser, 229 parts of ethyl acetate, 0.2 part of azobisisobutyronitrile, 95 parts of n-butyl acrylate and 5 parts of acrylic acid were added. The solution was polymerized at 60 ° C. to obtain an acrylic polymer solution A having an acrylic polymer (a) concentration of 30% by weight. The acrylic polymer (a) had a weight average molecular weight of 750,000.

(Synthesis of acrylic polymer (b))
In a reactor equipped with a thermometer, stirrer, nitrogen inlet tube and reflux condenser, 146 parts of ethyl acetate, 0.2 part of azobisisobutyronitrile, 95 parts of 2-ethylhexyl acrylate and 5 parts of acrylic acid The solution was polymerized at 60 ° C. to obtain an acrylic polymer solution B having an acrylic polymer (b) concentration of 40% by weight. The acrylic polymer (b) had a weight average molecular weight of 670,000.

(Synthesis of acrylic polymer (c))
In a reactor equipped with a thermometer, stirrer, nitrogen inlet tube and reflux condenser, 182 parts of ethyl acetate, 0.2 part of azobisisobutyronitrile, 45 parts of 2-ethylhexyl acrylate, n-butyl acrylate 45 parts, 5 parts of 2-hydroxyethyl acrylate and 5 parts of acrylic acid were charged, and solution polymerization was performed at 60 ° C. to obtain an acrylic polymer solution C having an acrylic polymer (c) concentration of 35% by weight. . The acrylic polymer (c) had a weight average molecular weight of 690,000.

(Production of adhesive tape)
An isocyanate-based crosslinking agent (trade name “Coronate L”, manufactured by Nippon Polyurethane Industry Co., Ltd.) is added to the acrylic polymer solution A so as to be 3 parts per 100 parts of the acrylic polymer (a). The pressure-sensitive adhesive composition (a) was coated on a 25 μm-thick polyethylene terephthalate (PET) film so that the dry thickness was 20 μm, and then dried at 100 ° C. for 2 minutes to form a pressure-sensitive adhesive layer A. Was made.

  Further, an isocyanate-based crosslinking agent (trade name “Coronate L”, manufactured by Nippon Polyurethane Industry Co., Ltd.) is added to the acrylic polymer solution B so as to be 3 parts per 100 parts of the acrylic polymer (b). The adhesive composition (b) was applied onto a 38 μm-thick polyethylene terephthalate (PET) film that had been subjected to a release treatment so that the dry thickness was 20 μm, and then dried at 100 ° C. for 2 minutes. An adhesive layer B was prepared.

  Next, the acrylic polymer solution C was diluted with ethyl acetate so that the solid content concentration of the acrylic polymer (c) was 5 wt% to prepare an intermediate layer composition (c). Thereafter, the composition is applied onto the prepared pressure-sensitive adhesive layers A and B so that the total dry thickness is 0.1 μm, and the applied surfaces are bonded together to form an intermediate layer C. It was. An adhesive tape was prepared by aging at 50 ° C. for 2 days for the reaction of the isocyanate-based crosslinking agent.

[Examples 2 to 14, Comparative Example 1]
The types and amounts of monomers used for the synthesis of acrylic polymers (a) to (c), the amount of crosslinking agent, and the thickness of each pressure-sensitive adhesive layer were changed to the values described in Tables 1 and 2. Except for this, the same operation as in Example 1 was performed to prepare each adhesive tape.

Example 15
(Synthesis of acrylic polymer (a))
In a reactor equipped with a thermometer, a stirrer, a nitrogen introduction tube and a reflux condenser, 229 parts of ethyl acetate, 0.2 part of azobisisobutyronitrile, 95 parts of n-butyl acrylate and 5 parts of acrylic acid were added. The solution was polymerized at 60 ° C. to obtain an acrylic polymer solution A having an acrylic polymer (a) concentration of 30% by weight. The acrylic polymer (a) had a weight average molecular weight of 750,000.

(Synthesis of acrylic polymer (b))
In a reactor equipped with a thermometer, stirrer, nitrogen inlet tube and reflux condenser, 146 parts of ethyl acetate, 0.2 part of azobisisobutyronitrile, 95 parts of 2-ethylhexyl acrylate and 5 parts of acrylic acid The solution was polymerized at 60 ° C. to obtain an acrylic polymer solution B having an acrylic polymer (b) concentration of 40% by weight. The acrylic polymer (b) had a weight average molecular weight of 670,000.

(Synthesis of acrylic polymer (c))
In a reactor equipped with a thermometer, stirrer, nitrogen inlet tube and reflux condenser, 182 parts of ethyl acetate, 0.2 part of azobisisobutyronitrile, 45 parts of 2-ethylhexyl acrylate, n-butyl acrylate 45 parts, 5 parts of 2-hydroxyethyl acrylate and 5 parts of acrylic acid were charged, and solution polymerization was performed at 60 ° C. to obtain an acrylic polymer solution C having an acrylic polymer (c) concentration of 35% by weight. . The acrylic polymer (c) had a weight average molecular weight of 690,000.

(Synthesis of acrylic polymer (ca))
In a reactor equipped with a thermometer, a stirrer, a nitrogen inlet tube and a reflux condenser, 182 parts of ethyl acetate, 0.2 part of azobisisobutyronitrile, 90 parts of n-butyl acrylate, 2-hydroxyethyl acrylate 5 parts and 5 parts of acrylic acid were charged, and solution polymerization was performed at 60 ° C. to obtain an acrylic polymer solution C ′ having an acrylic polymer (ca) concentration of 35% by weight. The acrylic polymer (ca) had a weight average molecular weight of 720,000.

(Synthesis of acrylic polymer (cb))
In a reactor equipped with a thermometer, stirrer, nitrogen inlet tube and reflux condenser, 182 parts of ethyl acetate, 0.2 part of azobisisobutyronitrile, 90 parts of 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate 5 parts and 5 parts of acrylic acid were charged, and solution polymerization was performed at 60 ° C. to obtain an acrylic polymer solution C ″ having an acrylic polymer (cb) concentration of 35% by weight.

  The acrylic polymer (cb) had a weight average molecular weight of 680,000.

(Production of adhesive tape)
An isocyanate-based crosslinking agent (trade name “Coronate L”, manufactured by Nippon Polyurethane Industry Co., Ltd.) is added to the acrylic polymer solution A so as to be 3 parts per 100 parts of the acrylic polymer (a). The pressure-sensitive adhesive composition (a) was coated on a 25 μm-thick polyethylene terephthalate (PET) film so that the dry thickness was 20 μm, and then dried at 100 ° C. for 2 minutes to form a pressure-sensitive adhesive layer A. Was made.

  Further, an isocyanate-based crosslinking agent (trade name “Coronate L”, manufactured by Nippon Polyurethane Industry Co., Ltd.) is added to the acrylic polymer solution B so as to be 3 parts per 100 parts of the acrylic polymer (b). The adhesive composition (b) was applied onto a 38 μm-thick polyethylene terephthalate (PET) film that had been subjected to a release treatment so that the dry thickness was 20 μm, and then dried at 100 ° C. for 2 minutes. An adhesive layer B was prepared.

  Next, the acrylic polymer solution C, the acrylic polymer solution C ′ and the acrylic polymer solution C ″ are mixed at a weight ratio of 1: 1: 1, and the mixture is mixed with the acrylic polymer (c ), Diluted with ethyl acetate so that the total solids concentration of the acrylic polymer (ca) and acrylic polymer (cb) is 5 wt%, to produce an intermediate layer composition (c) did. Thereafter, the composition is applied onto the prepared pressure-sensitive adhesive layers A and B so that the total dry thickness is 0.1 μm, and the applied surfaces are bonded together to form an intermediate layer C. It was. An adhesive tape was prepared by aging at 50 ° C. for 2 days for the reaction of the isocyanate-based crosslinking agent.

[Examples 16 to 24]
Types and amounts of monomers used for the synthesis of acrylic polymers (a) to (c), (ca) and (cb), amounts of crosslinking agent, and thickness of each pressure-sensitive adhesive layer Except that the thickness was changed to the values described in Tables 3 and 4, the same operation as in Example 15 was performed to prepare each adhesive tape.

[Examples 25 to 28]
The types and amounts of monomers used for the synthesis of acrylic polymers (a) to (c), the amount of crosslinking agent, and the thickness of each pressure-sensitive adhesive layer were changed to the values shown in Table 5. Except for the above, the same operation as in Example 1 was performed to prepare each adhesive tape.

Example 29
Instead of the acrylic polymer solution C, the same operation as in Example 23 was performed except that a 5% by weight (solid content) aqueous solution of polyallylamine (trade name “PAA-15C”, manufactured by Nittobo) was used. An adhesive tape was prepared.

Example 30
Instead of the acrylic polymer solution C, the same operation as in Example 23 was performed except that a 5% by weight (solid content) aqueous solution of polyallylamine (trade name “PAA-03”, manufactured by Nittobo) was used. An adhesive tape was prepared.

Example 31
Instead of the acrylic polymer solution C, the same operation as in Example 23 was performed except that a 5% by weight (solid content) aqueous solution of polyallylamine (trade name “PAA-1112”, manufactured by Nittobo) was used. An adhesive tape was prepared.

[Example 32]
Instead of the acrylic polymer solution C, the same operation as in Example 23 was performed except that a 5% by weight (solid content) aqueous solution of polydiallylamine (trade name “PAS-21”, manufactured by Nittobo) was used. An adhesive tape was prepared.

Example 33
Example 23 except that 5% by weight (solid content) aqueous solution of a diallylamine acetate / sulfur dioxide copolymer (trade name “PAS-92A”, manufactured by Nittobo Co., Ltd.) was used in place of the acrylic polymer solution C. The same operation was performed to produce an adhesive tape.

Example 34
Example 23 except that 5% by weight (solid content) aqueous solution of diallylamine hydrochloride / maleic acid copolymer (trade name “PAS-410C”, manufactured by Nittobo Co., Ltd.) was used in place of the acrylic polymer solution C. The same operation was performed to produce an adhesive tape.

Example 35
Implemented except that 5% by weight (solid content) aqueous solution of diallyldimethylammonium chloride / acrylamide copolymer (trade name “PAS-J-81L”, manufactured by Nittobo) was used in place of the acrylic polymer solution C. The same operation as in Example 23 was performed to produce an adhesive tape.

〔Evaluation method〕
(1) Throwing force (interlayer adhesion)
As a primer, trade name “RC-1017” manufactured by Lord Far East Incorporated was spread on a 38 μm-thick polyethylene terephthalate (PET) film with a waste cloth, and allowed to dry at room temperature for 30 minutes. The release liner covering the surface of the adhesive tape is peeled off, and this primer-treated PET film is attached to the tape and backed, and a laminator (two rolls, temperature 80 ° C., pressure 0.3 MPa, rotation speed 0.5 m / min. 2 round trips) and aged overnight. This was cut into a size of 20 mm in width and 80 mm in length to produce a test piece. Using double-sided tape, primer-treated PET affixed to the surface layer side is affixed to a coated plate with double-sided tape, and in accordance with JIS Z0237, the tensile force is peeled off from the bulk side at a pulling speed of 300 mm / min at a pulling angle of 180 degrees. (Interlayer adhesion) (N / 20 mm width) was measured.

  Tables 1 to 6 show the measurement results of the anchoring force (interlayer adhesive force) of each pressure-sensitive adhesive tape obtained in the above-described Examples and Comparative Examples.

Abbreviations in Tables 1 to 5 are as follows.
n-BA; n-butyl acrylate 2-EHA; 2-ethylhexyl acrylate i-NA; isononyl acrylate acrylate; 2-HEA acrylate; 2-hydroxyethyl acrylate 4-HBA; 4-hydroxybutyl acrylate DMAEA; dimethyl Aminoethyl acrylate DMAPAA; Dimethylaminopropylacrylamide C / L; Isocyanate-based crosslinking agent (trade name “Coronate L”, manufactured by Nippon Polyurethane Industry Co., Ltd.)
The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  Since the multilayer adhesive article according to the present invention has a high interlayer adhesion, it can be suitably used for various adhesive sheets.

Claims (11)

A pressure-sensitive adhesive layer (A) formed from a pressure-sensitive adhesive composition (a) containing an acrylic polymer (a) as a main component;
A pressure-sensitive adhesive layer (B) formed from a pressure-sensitive adhesive composition (b) containing the acrylic polymer (b) as a main component;
An intermediate layer (C) disposed between the pressure-sensitive adhesive layer (A) and the pressure-sensitive adhesive layer (B),
The pressure-sensitive adhesive composition (a) and the pressure-sensitive adhesive composition (b) each further contain a compound having two or more functional groups capable of reacting with active hydrogen in the molecule,
The intermediate layer (C) is formed from an intermediate layer composition (c) containing a polymer (c) obtained by polymerizing a monomer composition (c) containing a monomer containing active hydrogen. Sticky article.   The multilayer adhesive article according to claim 1, wherein the monomer containing active hydrogen is a monomer containing one or more functional groups selected from the group consisting of a carboxyl group, a hydroxyl group, and an amino group. . The acrylic polymer (a) is obtained by polymerizing the monomer composition (a),
The acrylic polymer (b) is obtained by polymerizing the monomer composition (b),
The monomer composition (c) includes a main component monomer of the monomer composition (a) and a main component monomer of the monomer composition (b). Or the multilayer adhesive article of 2.   The monomer composition (c) includes all monomers contained in the monomer composition (a) and all monomers contained in the monomer composition (b). The multilayer adhesive article according to claim 3.   The said compound which has two or more functional groups in a molecule | numerator which can be reacted with an active hydrogen contained in an adhesive composition (a) and an adhesive composition (b) is a polyfunctional isocyanate compound. The multilayer adhesive article according to any one of 4.   The multilayer adhesive article according to any one of claims 1 to 5, wherein the monomer containing active hydrogen is a monomer containing a hydroxyl group.   The multilayer adhesive article according to any one of claims 1 to 5, wherein the monomer containing active hydrogen is a monomer containing an amino group. The intermediate layer (C) includes a polymer (ca) obtained by polymerizing the monomer composition (ca), and a polymer (c-) obtained by polymerizing the monomer composition (cb). further containing one or more selected from the group consisting of b),
The monomer composition (ca) includes the monomer containing active hydrogen and the main component monomer of the monomer composition (a),
The monomer composition (cb) includes any one of the monomers containing active hydrogen and the main monomer of the monomer composition (b). 2. The multilayer adhesive article according to item 1. At least one selected from the group consisting of the acrylic polymer (a) and the acrylic polymer (b) contains an acid group,
The multilayer adhesive article according to any one of claims 1 to 8, wherein the polymer (c) contains a primary to tertiary amino group. At least one selected from the group consisting of the acrylic polymer (a) and the acrylic polymer (b) contains an acid group,
9. At least one selected from the group consisting of the polymer (c), the polymer (ca), and the polymer (cb) contains a primary to tertiary amino group. A multilayer adhesive article as described in 1.   The adhesive sheet provided with the multilayer adhesive article of any one of Claims 1-10 as an adhesive layer.