JP5811525B2 - Adhesive composition and adhesive sheet - Google Patents

Description

  The present invention relates to an adhesive composition and an adhesive sheet.

  Curing systems mainly used for photocuring include curing by radicals and curing by cations. In the curing by radicals, a photo radical generator and a radical polymerizable resin such as a (meth) acrylate resin are used. The photo radical generator generates radicals by light irradiation, and the radical polymerizable resin is cured by the radicals. In this curing by radicals, generally, the obtained adhesive force is low, curing shrinkage is large, and heat resistance is poor. In the curing with cations, a photoacid generator and a cationic polymerizable resin such as an epoxy resin are used. The photoacid generator generates an acid by light irradiation, and the cationic polymerizable resin is cured by the acid. Curing with this cation provides high adhesion and small cure shrinkage, but generates acid and thus has the problem of causing corrosion of metal foils and the like.

  As one means for solving the problem of curing due to radicals and cations as described above, research on curing by anions using a photobase generator that generates a basic compound by light irradiation has been conducted in recent years. For curing with anions, a photobase generator and a base polymerizable resin such as an epoxy resin are used. However, conventional photobase generators have poor basic compound generation efficiency, and the generated basic compound is a primary or secondary amine, so the basicity is low, and the base polymerizability of an epoxy resin or the like is low. It does not have catalytic activity to fully cure the resin.

  Then, when this inventor researched, it discovered that the said problem could be solved according to a specific base generator (refer patent document 1). According to this base generator, a base having a catalytic activity capable of sufficiently curing the base polymerizable resin can be generated by light irradiation and heating. In addition, in patent document 1, this inventor makes this photosensitive resin composition for pattern formation contain this base generator.

JP 2010-106233 A

  By the way, in general, a photo-curing type adhesive composition is required to have a long working life and a property that can be cured at a low temperature without generating an acid that corrodes the adherend. A photo-curing adhesive composition having such properties has not been known so far.

  The present invention has been made in view of the above circumstances, and is cured at a low temperature without generating an acid, and has a workability that can be adjusted for a usable time, and has a good workability. It is to provide a landing sheet.

  Specifically, the present invention provides the following.

(1) A base generator that generates a base by heating after light irradiation, a curable compound having at least one epoxy group in the molecule, and a thermoplastic resin having a glass transition temperature (Tg) of −10 to 30 ° C. The adhesive is characterized in that the content of the thermoplastic resin is 37 to 80 parts by mass with respect to 100 parts by mass of the total amount of the curable compound and the thermoplastic resin. Agent composition.

  (2) The adhesive composition according to (1), wherein the base generator generates a base having at least two or more amino groups.

  (3) The adhesive composition according to (1) or (2), wherein the curable compound is an epoxy resin.

（式中、Ｒ^１及びＲ^２は、それぞれ独立に水素原子又は１価の有機基を表す。Ｒ^１及びＲ^２は、それらが結合して環状構造を形成していてもよい。ただし、Ｒ^１及びＲ^２のうち、少なくとも１つは１価の有機基を表す。Ｒ^３〜Ｒ^６は、それぞれ独立に水素原子、ハロゲン原子又は有機基を表す。Ｒ^３〜Ｒ^６は、それらの２つ以上が結合して環状構造を形成していてもよい。） (4) The said base generator is an adhesive composition in any one of (1)-(3) represented by the following general formula (I).

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a monovalent organic group. R ¹ and R ² may combine with each other to form a cyclic structure. ^At least one of R ¹ and R ² represents a monovalent organic group, R ^{3 to} R ⁶ each independently represents a hydrogen atom, a halogen atom or an organic group, and R ^{3 to} R ⁶ represent 2 of them. Two or more may combine to form a cyclic structure.)

  (5) An adhesive sheet having at least an adhesive layer comprising the adhesive composition according to any one of (1) to (4).

  According to the adhesive composition of the present invention, the adhesive composition can be cured at a low temperature without generating an acid, and the working life can be adjusted, and the workability is good. And an adhesive sheet can be provided.

  Hereinafter, specific embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and may be implemented with appropriate modifications within the scope of the object of the present invention. Can do.

[Adhesive composition]
The adhesive composition of the present invention has a base generator that generates a base by heating after light irradiation, a curable compound having at least one epoxy group in the molecule, and a glass transition temperature (Tg) of −. A thermoplastic resin having a temperature of 10 to 30 ° C., and the content of the thermoplastic resin is 37 to 80 parts by mass with respect to 100 parts by mass of the total amount of the curable compound and the thermoplastic resin. It is characterized by that. Hereinafter, the base generator, the curable compound, the thermoplastic resin, and other components will be described in order.

<Base generator>
The base generator contained in the adhesive composition of the present invention generates a base by heating after light irradiation. Such a base generator is not particularly limited. For example, a base generator represented by the following general formula (I) is preferable. This base generator is described in, for example, Patent Document 1 described above.

  The base generator represented by the general formula (I) is a kind of photobase generator, and generation of a base is promoted by appropriately heating after light irradiation. The base generator represented by the general formula (I) can efficiently generate a base with a small amount of light irradiation by combining light irradiation and heating. The photobase generator refers to an agent that does not exhibit activity under normal conditions of normal temperature and pressure, but generates a base when light is applied as an external stimulus.

Since the base generator represented by the above general formula (I) has the above specific structure, (—CH═CH—C (═O) —) in the general formula (I) is irradiated with light. The moiety isomerizes to the cis isomer and is further cyclized by heating to produce the base amine, NHR ¹ R ² . And the epoxy group is ring-opened by the produced amine, and addition polymerization with the amine occurs.

In the general formula (I), R ¹ and R ² are each independently a hydrogen atom or a monovalent organic group, and at least one of R ¹ and R ² is a monovalent organic group. NHR ¹ R ² is a base (in the present invention, “basic substance” is simply referred to as a base), but R ¹ and R ² are each an organic group that does not contain an amino group. Is preferred. If R ¹ and R ² contain an amino group, the base generator itself becomes a base and reacts with an epoxy group, which may impair stability over time.

  Examples of the monovalent organic group include a saturated or unsaturated alkyl group, a saturated or unsaturated cycloalkyl group, an aryl group, an aralkyl group, a saturated or unsaturated halogenated alkyl group, and the like. These organic groups may contain a bond or substituent other than a hydrocarbon group such as a hetero atom in the organic group, and may be linear or branched.

R ¹ and R ² may be bonded to each other to form a cyclic structure. The cyclic structure is a combination of two or more selected from the group consisting of saturated or unsaturated alicyclic hydrocarbons, heterocycles, and condensed rings, and the alicyclic hydrocarbons, heterocycles, and condensed rings. It may be a structure.

The bond other than the hydrocarbon group in the organic group of R ¹ and R ² is not particularly limited, and examples thereof include an ether bond, a thioether bond, a carbonyl bond, a thiocarbonyl bond, an ester bond, an amide bond, and a urethane. Examples include a bond, an imino bond (—N═C (—R) —, —C (═NR) —, where R is a hydrogen atom or a monovalent organic group), a carbonate bond, a sulfonyl bond, and the like.

The substituent other than the hydrocarbon group in the organic group of R ¹ and R ² is not particularly limited, and examples thereof include a halogen atom, a hydroxyl group, a mercapto group, a cyano group, a silyl group, a silanol group, and an alkoxy group. , Alkoxycarbonyl group, nitro group, carboxyl group, acyl group, acyloxy group, sulfino group, sulfo group, saturated or unsaturated alkyl ether group, saturated or unsaturated alkyl thioether group, aryl ether group, aryl thioether group, amino group ( —NH ₂ , —NHR, —NRR ′: Here, R and R ′ are each independently a hydrocarbon group. These groups may be linear, branched or cyclic.

Since the produced amine is NHR ¹ R ^2, it is a primary amine or a secondary amine. The amine includes an aliphatic amine and an aromatic amine, respectively.

  Examples of the aliphatic primary amine include methylamine, ethylamine, propylamine, isopropylamine, n-butylamine, sec-butylamine, tert-butylamine, pentylamine, isoamylamine, tert-pentylamine, cyclopentylamine, hexylamine, Examples include cyclohexylamine, heptylamine, cycloheptaneamine, octylamine, 2-octaneamine, 2,4,4-trimethylpentan-2-amine, and cyclooctylamine.

  Examples of the aromatic primary amine include aniline, 2-aminophenol, 3-aminophenol, 4-aminophenol and the like.

  Examples of the aliphatic secondary amine include dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, ethylmethylamine, aziridine, azetidine, pyrrolidine, piperidine, azepane, azocan, methylaziridine, dimethylaziridine, and methylazetidine. Dimethyl azetidine, trimethyl azetidine, methyl pyrrolidine, dimethyl pyrrolidine, trimethyl pyrrolidine, tetramethyl pyrrolidine, methyl piperidine, dimethyl piperidine, trimethyl piperidine, tetramethyl piperidine, pentamethyl piperidine, etc., among them alicyclic amine Is preferred.

  Examples of the aromatic secondary amine include methylaniline, diphenylamine, N-phenyl-1-naphthylamine and the like.

Further, the NHR ¹ R ^{2 to be} generated is not only a base such as monoamine having only one NH group capable of forming an amide bond, but also two or more NH groups capable of forming an amide bond such as diamine, triamine, and tetraamine. In the present invention, it is preferably diamine or more from the viewpoint of the physical properties of the addition-polymerized cured product and the adhesive strength after curing.

When the generated NHR ¹ R ² is a base having two or more NH groups, it has an NH group capable of forming an amide bond at one or more terminals of R ¹ and / or R ^{2 in} the general formula (I). Examples include a structure in which a photolatent site that generates a base by light irradiation and heating is further bonded. The photolatent site includes a residue excluding R ¹ and / or R ² in the general formula (I) at one or more terminals of R ¹ and / or R ^{2 in} the general formula (I). Furthermore, the structure which has couple | bonded is mentioned.

  Examples of amines higher than diamine include ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8- Linear aliphatic alkylene diamines such as octanediamine, 1,9-nonanediamine, 1,10-decanediamine; 1-butyl-1,2-ethanediamine, 1,1-dimethyl-1,4-butanediamine, 1 -Ethyl-1,4-butanediamine, 1,2-dimethyl-1,4-butanediamine, 1,3-dimethyl-1,4-butanediamine, 1,4-dimethyl-1,4-butanediamine, 2 Branched aliphatic alkylenediamines such as 1,3-dimethyl-1,4-butanediamine; cyclohexanediamine, methylcyclohexanediamine, Cycloaliphatic diamines such as holondiamine, norbornanedimethylamine, tricyclodecanedimethylamine, mensendiamine; p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylenediamine, 4,4′- Aromatic diamines such as diaminodiphenylmethane; triamines such as benzenetriamine, melamine and 2,4,6-triaminopyrimidine; tetraamines such as 2,4,5,6-tetraaminopyrimidine and the like.

  More preferably, the base generated from the base generator is a primary diamine from the viewpoint of moisture permeability barrier properties, and the primary diamine is an aliphatic alkylene diamine having 1 to 6 carbon atoms or an aromatic diamine. An aromatic diamine having 2 or less rings and 1 or less carbon atoms in the side chain.

As the base generator that generates a base by heating after light irradiation, a base generator represented by the following general formula (II) is particularly preferable.

^{Wherein, R 11} is an alkylene group having 1 to 6 carbon atoms, or ^{a -C-R} 12 -C-. R ¹² is a phenylene group or a naphthylene group, and is preferably a phenylene group. R ^{3 to} R ¹⁰ are each independently a hydrogen atom, a halogen atom or an organic group.

A method for synthesizing the base generator represented by the general formula (II) will be described with reference to the base generator represented by the following general formula (III) in which R ¹¹ is an n-hexylene group. In addition, the synthesis | combining method of the base generator represented by the said general formula (II) is not limited to this, It can synthesize | combine by several conventionally well-known methods.

  The base generator represented by the general formula (III) can be synthesized, for example, by the following method. First, ethoxycarbonylmethyl (triphenyl) phosphonium bromide and 2-hydroxy-4-methoxybenzaldehyde are dissolved in methanol, and a methanol solution of potassium carbonate is slowly added dropwise thereto and stirred. After confirming the completion of the reaction by TLC, filtration is performed, potassium carbonate is removed, and the mixture is concentrated under reduced pressure. After concentration, an aqueous sodium hydroxide solution is added and stirred. After completion of the reaction, triphenylphosphine oxide is removed by filtration, and then concentrated hydrochloric acid is added dropwise to make the reaction solution acidic. The precipitate is collected by filtration and washed with a small amount of chloroform to give 2-hydroxy-4-methoxycinnamic acid. Next, the 2-hydroxy-4-methoxycinnamic acid obtained above was dissolved in dehydrated tetrahydrofuran under a nitrogen atmosphere, and 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride was dissolved in an ice bath. Add. Thereafter, 1,6-diaminohexane is added and stirred overnight. After completion of the reaction, the reaction solution is concentrated and dissolved in water. Extraction with chloroform, washing with an aqueous solution of hydrogen carbonate, hydrochloric acid and saturated saline, drying with sodium sulfate, and concentration can be performed to obtain a base generator represented by the above general formula (III). it can. The synthesized base generator represented by the general formula (III) generates 1,6-diaminohexane as a base.

Thus, a base generator that generates a desired base can be easily synthesized. For example, when 1,4-diaminobutane is to be generated as a base, a base generator represented by the above general formula (II) in which R ¹¹ is an n-butylene group may be synthesized. In the above synthesis method, 1,4-diaminobutane may be added instead of 1,6-diaminohexane.

R ^{3 to} R ^{6 in} the general formula (I) and R ^{3 to} R ¹⁰ in the general formula (II) are each independently a hydrogen atom, a halogen, or a monovalent organic group. Here, two or more of R ^{3 to} R ^{6 in} the general formula (I) may be bonded to form a cyclic structure, and may include a bond of a hetero atom. Further, two or more of R ^{3 to} R ^{6 in} the general formula (II) or two or more of R ^{7 to} R ¹⁰ may be bonded to form a cyclic structure, and include a bond of a hetero atom. May be. Examples of halogen include fluorine, chlorine, bromine and the like. The monovalent organic group is not particularly limited, and examples thereof include a saturated or unsaturated alkyl group, a saturated or unsaturated cycloalkyl group, an aryl group, an aralkyl group, and a saturated or unsaturated halogenated alkyl group. These organic groups may contain a bond or substituent other than a hydrocarbon group such as a hetero atom in the organic group, and may be linear or branched.

The bond other than the hydrocarbon group in the organic group represented by R ^{3 to} R ⁶ of the general formula (I) or R ^{3 to} R ¹⁰ of the general formula (II) is not particularly limited, and may be an ether bond, Examples include a thioether bond, a carbonyl bond, a thiocarbonyl bond, an ester bond, an amide bond, a urethane bond, a carbonate bond, and a sulfonyl bond.

Substituents other than the hydrocarbon group in the organic groups of R ^{3 to} R ⁶ of the general formula (I) and R ^{3 to} R ¹⁰ of the general formula (II) are not particularly limited. Halogen atom, hydroxyl group, mercapto group, cyano group, silyl group, silanol group, alkoxy group, alkoxycarbonyl group, nitro group, carboxyl group, acyl group, acyloxy group, sulfino group, sulfo group, saturated or unsaturated alkyl ether group, Saturated or unsaturated alkyl thioether group, aryl ether group, aryl thioether group, amino group (—NH ₂ , —NHR, —NRR ′: where R and R ′ are each independently a hydrocarbon group), etc. . These groups may be linear, branched or cyclic. Among these, halogen atoms, hydroxyl groups, mercapto groups, cyano groups, silyl groups, silanol groups, alkoxy groups, alkoxycarbonyl groups, nitro groups, acyl groups, acyloxy groups, saturated or unsaturated alkyl ether groups, saturated or unsaturated groups. Saturated alkyl thioether groups, aryl ether groups, and aryl thioether groups are preferred.

Further, two or more of R ^{3 to} R ^{6 in} the general formula (I), two or more of R ^{3 to} R ^{6 in} the general formula (II), and R ^{7 to} R ^{10 in} the general formula (II) Two or more may combine to form a ring structure to form a ring structure. The cyclic structure is a combination of two or more selected from the group consisting of saturated or unsaturated alicyclic hydrocarbons, heterocycles, and condensed rings, and the alicyclic hydrocarbons, heterocycles, and condensed rings. It may be a structure. For example, R ³ to R ⁶ are formed by combining two or more of them, naphthalene share atoms of the benzene ring of R ³ to R ⁶ are attached, anthracene, phenanthrene, and fused ring indene You may do it.

Moreover, it is possible to adjust the wavelength of light to be absorbed by introducing one or more substituents into R ^{3 to} R ⁶ of the general formula (I) and R ^{3 to} R ¹⁰ of the general formula (II). It is also possible to absorb a desired wavelength by introducing a substituent. For example, the absorption wavelength can be shifted to a longer wavelength by introducing a substituent that extends the conjugated chain of the aromatic ring.

  Guidance on what substituents should be introduced in order to shift the absorption wavelength to the desired wavelength depends on the Interpretation of the Ultraviolet Natural Products (AI Scott 1964) and the spectrum of organic compounds. A table described in the identification method 5th edition (RM Silverstein 1993) is cited as a reference.

Specifically, R ^{3 to} R ^{6 in} the general formula (I) and R ^{3 to} R ^{10 in} the general formula (II) are specifically an alkyl group having 1 to 10 carbon atoms and a cycloalkyl group having 4 to 13 carbon atoms. A cycloalkenyl group having 4 to 13 carbon atoms, an aryloxyalkyl group having 7 to 16 carbon atoms (-ROAr), an aralkyl group having 7 to 20 carbon atoms, an alkyl group having 2 to 11 carbon atoms having a cyano group, and a hydroxyl group. An alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an amide group having 2 to 11 carbon atoms, an alkylthio group having 1 to 10 carbon atoms (-SR), an acyl group having 1 to 10 carbon atoms, Ester group having 2 to 11 carbon atoms, aryl group having 6 to 20 carbon atoms, electron donating group and / or electron withdrawing group substituted aryl group having 6 to 20 carbon atoms, electron donating group and / or electron withdrawing A benzyl group, a cyano group, Fine methylthio group (-SCH ₃₎ or the like are preferable. The alkyl moiety may be linear, branched or cyclic. Further, R ³ to R ⁶ are formed by combining two or more of them, naphthalene share atoms of the benzene ring of R ³ to R ⁶ are attached, anthracene, phenanthrene, and fused ring indene In this case, the absorption wavelength is preferable from the viewpoint of increasing the wavelength.

  The structure represented by the general formulas (I) and (II) is a trans isomer and / or a cis isomer, and only the trans isomer may be used, or a mixture of the trans isomer and the cis isomer may be used.

  In general, a photobase generator decomposes its chemical structure upon light irradiation and generates a base (amine). However, the base generator contained in the adhesive composition of the present invention is heated by light irradiation. Generate a base. For example, in the base generators represented by the above general formulas (I) and (II), when irradiated with light, a cis-trans mutation occurs, and the phenolic hydroxyl group moiety disappears upon heating, resulting in a base. Will occur. That is, if it is not heated after irradiation with light, a base is not generated. Therefore, even if it coexists with a curable compound having at least one epoxy group in the molecule described later, the curing reaction does not proceed. Therefore, since the storage stability of the curable compound does not decrease, it is not necessary to adjust the progress of curing with a curing retarder as in the case of using a photoacid generator, for example. Since a hydrophilic material is used for the curing retarder, the hydrophilic material remains in the cured product, causing a decrease in moisture permeability barrier properties. When a base generator that does not generate odor is used, such a fear does not occur. In addition, in curing with radicals or curing with cations, curing proceeds immediately after light irradiation, so the pot life is short and inferior in workability, but in the adhesive composition of the present invention, by heating after light irradiation. Since it contains a base generator that generates a base, the pot life can be adjusted by adjusting the heating after light irradiation, and the workability is improved. This is an advantage of using the composition of the present invention as an adhesive.

  The content of the photobase generator in the resin composition of the present invention is preferably 10 to 200 parts by mass, and more preferably 10 to 150 parts by mass with respect to 100 parts by mass of the curable compound described later. When the content of the photobase generator is less than 10 parts by mass, the generated base is less than the equivalent, and curing may not proceed sufficiently. Exceeding 200 parts by mass is not preferable because excessive bases are generated by light irradiation, and some bases may not react with the functional groups of the curable compound, and sufficient adhesive strength may not be obtained. .

<Curable compound>
The adhesive composition of the present invention contains a curable compound having at least one epoxy group in the molecule. According to the curable compound having at least one epoxy group in the molecule, a cured product having high adhesive strength can be obtained.

  The curable compound having at least one epoxy group in the molecule is not particularly limited, and examples thereof include bisphenol type epoxy resins such as bisphenol A type epoxy resin and bisphenol F type epoxy resin, and phenol novolac type epoxy resins. , Novolak type epoxy resin such as cresol novolac type epoxy resin, aliphatic epoxy resin, cycloaliphatic epoxy resin, polyfunctional epoxy resin, biphenyl type epoxy resin, glycidyl ether type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type Examples include epoxy resins, alcohol-type epoxy resins such as hydrogenated bisphenol A-type epoxy resins, rubber-modified epoxy resins, urethane-modified epoxy resins, and epoxy group-containing acrylic resins. You may use these individually or in combination of 2 or more types. Among these, epoxy resins are preferable, and bisphenol-type epoxy resins such as bisphenol A-type epoxy resin and bisphenol F-type epoxy resin are widely available in grades with different molecular weights. It is more preferable in that it can be set. In addition, the epoxy resin having a triazine nucleus in the skeleton forms a uniform film when applied (100 ° C., 10 minutes) after applying a coating solution comprising an adhesive composition containing the epoxy resin, It is preferable in terms of facilitating peeling from the release PET when the temperature reaches room temperature.

  The curable compound preferably has high reactivity and low epoxy equivalent in order to achieve curing in a short time. For example, the epoxy equivalent is 100 to 500 g / eq. It is preferable to be within the range. Here, the epoxy equivalent is the number of grams of a resin containing 1 gram equivalent of an epoxy group measured by a method according to JIS K7236.

  As a commercial item of the said sclerosing | hardenable compound, for example, "EPICLON EXA-835LV", "EPICLON 850S", "EPICLON N740", "EPICLON EXA-830CRP", "EPICLON EXA-830LVP", "EPICLON" by DIC Corporation “HP-820”, “jER 828”, “jER 806”, “jER 1001”, “jER 801N”, “jER 807”, “jER 152”, “jER 604”, “jER 630” manufactured by Mitsubishi Chemical Corporation , “JER 871”, “jER YX8000”, “jER YX8034”, “jER YX4000”, “Acryset BPA-328” manufactured by Nippon Shokubai Co., Ltd., “TEPIC SP” manufactured by Nissan Chemical Co., Ltd., manufactured by ADEKA Corporation E P4100 series, EP4000 series, EPU series, Daicel Chemical Industries Co., Ltd. Celoxide side series, Eporide series, EHPE series, Toto Kasei Co., Ltd. YD series, YDF series, YDCN series, YDB series, Nagase ChemteX Corporation Examples include the Denacol series manufactured by the company and the Epolite series manufactured by Kyoeisha Chemical Co., Ltd.

  The mass average molecular weight of the curable compound is preferably within the range of 100 to 1000, for example. If the mass average molecular weight of the curable compound is less than 100, the film physical properties of the cured product may be reduced, and if it exceeds 1000, it may be difficult to handle because it is highly viscous or solid. is there. Here, the mass average molecular weight is a value in terms of polystyrene when measured by gel permeation chromatography (GPC).

<Thermoplastic resin>
As for the thermoplastic resin contained in the adhesive composition of this invention, glass transition temperature (Tg) is -10-30 degreeC, and it is preferable that it is 0-30 degreeC. The kind of the thermoplastic resin is not particularly limited, and for example, acrylic resin, polyester resin, urethane resin, polyamide resin, silicone resin, natural rubber, polyether, polycarbonate, polyvinyl ether, polyvinyl chloride, ethylene -Various general-purpose pressure-sensitive adhesives such as vinyl acetate copolymer and polyvinyl acetate. You may use these individually or in combination of 2 or more types. In the adhesive composition of the present invention, an acrylic resin and a polyester resin are materials that are widely used in the field of pressure-sensitive adhesive materials, and are preferable because the pressure-sensitive adhesive force to a base material can be appropriately controlled. .

  The acrylic resin is not particularly limited, and examples thereof include polymers and copolymers of (meth) acrylic acid and / or various derivatives thereof. (Meth) acrylic acid derivatives include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic Aromatic groups such as (meth) acrylic acid alkyl esters such as lauryl acid, (meth) acrylic acid hydroxyl ethyl, (meth) acrylic acid hydroxyl alkyl esters such as hydroxyl propyl, and (meth) acrylic acid benzyl (Meth) acrylic acid ester containing, (meth) acrylic acid amide such as dimethyl (meth) acrylic acid amide, (meth) acrylic acid ester containing imide group such as imide acrylate TO-1492 (manufactured by Toagosei Co., Ltd.), Contains an epoxy group such as glycidyl (meth) acrylate ( Data), and acrylic acid esters. Moreover, the said copolymer also includes the copolymer of the said (meth) acrylic acid and / or its various derivatives, acrylonitrile, styrene, a butadiene, an allyl derivative, etc. Among these, those having an epoxy group are preferable from the viewpoint of adhesiveness. The introduction of the epoxy group can be performed by using a (meth) acryl compound containing an epoxy group. In addition, the mixture of the polymer which has an epoxy group, and the polymer which does not have may be sufficient.

  As a polyester resin, the polyester resin which consists of a reaction product of a polyhydric carboxylic acid component and a polyhydric alcohol component is mentioned, for example. Examples of the polyvalent carboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid, and paraphenylene dicarboxylic acid; and trivalent or higher aromatics such as trimellitic acid. Polyvalent carboxylic acid; cycloaliphatic polycarboxylic acid containing 5-membered or 6-membered ring such as cyclohexanedicarboxylic acid; aliphatic polycarboxylic acid such as succinic acid, glutaric acid, adipic acid, suberic acid, dodecanedioic acid Etc. You may use these individually or in combination of 2 or more types. Examples of the polyhydric alcohol component include aliphatic diols such as ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and neopentyl glycol; Trihydric or higher polyhydric alcohols such as trimethylolpropane and pentaerythritol; alicyclic diols such as 1,4-cyclohexanedimethanol; polyhydric alcohols having an ether structure such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol; Examples thereof include polyester polyol, polycarbonate polyol, polymer polyol, and rosinol. You may use these individually or in combination of 2 or more types.

  The thermoplastic resin preferably has a mass average molecular weight in the range of 10,000 to 1,000,000, and more preferably 15,000 to 850,000. When the mass average molecular weight of the thermoplastic resin exceeds 1,000,000, the compatibility with the curable compound may be deteriorated. Here, the mass average molecular weight is a value in terms of polystyrene when measured by gel permeation chromatography (GPC).

In the adhesive composition of this invention , the said thermoplastic resin is contained in the ratio of 37-80 mass parts with respect to 100 mass parts of total amounts of the said sclerosing | hardenable compound and this thermoplastic resin . If it is the said range, it can be made to peel easily from a peeling film after solvent drying. In addition, since it is adhesive paste generate | occur | produced with respect to a peeling film as it is less than 37 mass parts, it is unpreferable. Moreover, when it exceeds 80 mass parts, the adhesive strength at the time of hardening will become inadequate.

  Conventional epoxy adhesives that do not contain a thermoplastic resin are generally in liquid form, resulting in uneven thickness at the time of application, the appearance of the joint end being lowered due to the protrusion of the adhesive, and curing is completed. It was necessary to fix with a tool, and the bonding work had to be complicated. However, according to the adhesive composition of the present invention, since the thermoplastic resin having the glass transition temperature is contained in the specific amount, the form after drying the solvent is not liquid, and the conventional epoxy system A pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer that can be easily peeled off from a release film at room temperature can be formed without causing troublesome work in adhesion such as a pressure-sensitive adhesive.

<Others>
The resin composition of the present invention may contain various additives such as an adhesion improver such as a coupling agent and a leveling agent, for example, as long as the object of the present invention is not impaired. For example, a silane coupling agent may be used in combination in order to improve interfacial adhesion. By using together with a silane coupling agent having a functional group capable of reacting with an epoxy group such as an amino group, an epoxy group, a mercapto group, a phenolic hydroxyl group, or a carboxyl group, the strength of the cured product and the adhesion to the adherend can be improved. Further improvement can be achieved. Further, a tackifier resin may be used in combination to increase the adhesive strength, a filler may be used in combination to improve the shear adhesive strength, or a photosensitizer may be used in combination to improve the photosensitivity. Good.

  In addition, when the silane coupling agent which has a functional group which can react with an epoxy group is used, the intensity | strength of hardened | cured material and the adhesiveness to a to-be-adhered body can further be improved. Examples of the functional group capable of reacting with the epoxy group include a primary amino group, a secondary amino group, a tertiary amino group, a mercapto group, an epoxy group, and a carboxyl group. Specifically, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) ) Aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane, Amino group-containing silanes such as γ-anilinopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, etc. No Lukapto group-containing silanes, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxy Epoxy bond-containing silanes such as silane, β-carboxyethyltriethoxysilane, β-carboxyethylphenylbis (2-methoxyethoxy) silane, N-β- (N-carboxymethylaminoethyl) -γ-aminopropyltri Examples thereof include carboxysilanes such as methoxysilane. You may use these individually or in combination of 2 or more types.

  The silane coupling agent is preferably contained in an amount of 0.1 to 12 parts by weight, more preferably 0.5 to 10 parts by weight, based on a total of 100 parts by weight of the curable compound and the thermoplastic resin. preferable.

  Examples of the tackifier resin include rosin resins, modified rosin resins, terpene resins, terpene phenol resins, aromatic modified terpene resins, C5 or C9 petroleum resins, coumarone resins, and the like. In particular, when the adherend is a polyolefin, high adhesive strength can be exhibited by using a rosin resin or a petroleum resin in combination.

  Examples of the filler include inorganic hollow bodies such as silica, clay, glass balloon, alumina balloon, and ceramic balloon, organic spherical bodies such as nylon beads, acrylic beads, and silicon beads, and organic hollow bodies such as vinylidene chloride balloons and acrylic balloons. And single fibers made of glass, polyester, rayon, nylon, cellulose, acetate and the like.

  Examples of the photosensitizer include anthracene, perylene, coronene, tetracene, benzanthracene, phenothiazine, flavin, acridine, ketocoumarin, thioxanthone derivatives, benzophenone, acetophenone, 2-chlorothioxanthone, and 2,4-dimethylthioxanthone. 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, isopropylthioxanthone and the like.

  Moreover, the adhesive composition of this invention may contain the solvent. When a solvent is contained, coatability can be improved. The solvent is not particularly limited, and examples thereof include aromatic hydrocarbon compounds, saturated or unsaturated hydrocarbon compounds, ethers, ketones, and esters. You may use these individually or in combination of 2 or more types.

  Furthermore, the adhesive composition of the present invention is a colorant such as a pigment or a dye, an inorganic filler such as calcium carbonate, talc, silica, alumina, aluminum hydroxide, silver, etc., as long as the properties of the present invention are not impaired. Conductive particles, flame retardant, boric acid ester and phosphoric acid ester, inorganic acid, organic acid and other preservatives, organic fillers such as acrylic rubber and silicone rubber, polyimide resin, polyamide resin, bisphenol A type phenoxy resin General-purpose phenoxy resins such as bisphenol F type phenoxy resin, bisphenol A / bisphenol F copolymer type phenoxy resin, polymers such as polymethacrylate resins, polyacrylate resins, polyvinyl butyral resin, SBS resin and its modified epoxy resin, and heat Plastic elastomers, plasticizers, organic solvents, antioxidants, antifoaming agents, caps Coupling agent, a leveling agent, may be appropriate amount of additives such as rheology control agents. By these additions, a composition having excellent resin strength, adhesive strength, flame retardancy, thermal conductivity, storage stability, workability, and the like, and a cured product thereof can be obtained.

(Light irradiation)
The adhesive composition of the present invention is cured by heating after light irradiation. The light used for the light irradiation is not particularly limited, and examples thereof include microwaves, infrared rays, visible rays, ultraviolet rays, X-rays, and γ rays. Among these, ultraviolet rays that are particularly easy to handle and can obtain relatively high energy are more preferable.

As irradiation light, the light of the wavelength range of 200-450 nm is preferable, and the light of the wavelength range of 300-450 nm is more preferable. The light source is not particularly limited, and for example, a high pressure mercury lamp, an ultra high pressure mercury lamp, a carbon arc lamp, a mercury vapor arc, a fluorescent lamp, an argon glow lamp, a halogen lamp, an incandescent lamp, a low pressure mercury lamp, a flash UV lamp, deep UV A lamp, a xenon lamp, a tungsten filament lamp, sunlight, etc. are mentioned. Using these light sources, the adhesive composition is cured by irradiating light so that the integrated light amount is in the range of 0.5 to 6 J / cm ² , preferably 1 to 6 J / cm ^2. Can do. If the integrated light amount is less than 0.5 J / cm ² , curing may be insufficient, and if it is less than 6 J / cm ² , the working time may be long, which is not preferable.

[Adhesive sheet]
The pressure-sensitive adhesive sheet of the present invention has at least a pressure-sensitive adhesive layer made of the above-mentioned pressure-sensitive adhesive composition. That is, the adhesive sheet of the present invention may have a configuration in which an adhesive layer is formed on a substrate as in, for example, a substrate / adhesive layer / release film, or a release. The structure may be a base-less double-sided adhesive sheet such as film / adhesive layer / release film. Since the above adhesive composition has tackiness before light irradiation, when it is formed into a sheet, it is laminated on a substrate such as a release-treated substrate or a release film, and the other surface is the same. It is preferable to laminate and coat with a release film or the like as a protective material that has been subjected to a release treatment. Hereinafter, the substrate, the release film, and the adhesive sheet will be described in order. In addition, the term “adhesive” means to include both adhesion and adhesion, and “adhesion” usually means temporary bonding assuming peeling, and “bonding” usually means permanent bonding that does not assume peeling. It is a concept that includes.

<Base material>
In the adhesive sheet of the present invention, the base material is not particularly limited, and an appropriate material such as a woven fabric, a knitted fabric, a non-woven fabric, or a film can be selected. It is preferable that it is transparent. Here, “transparent” does not necessarily need to be colorless and transparent, and may be colored and transparent, and means that the light transmittance in the visible region (380 to 780 nm) is 80% or more. The light transmittance can be measured (based on JIS-Z8701) using a commercially available spectrophotometer, for example, UV-3100PC manufactured by Shimadzu Corporation. When a material that does not transmit light is selected as the base material, the adhesive layer formed on the base material is irradiated with light from the adhesive layer side, and another base material is laminated from above. Then, it becomes possible to make it adhere by heating. In addition, since a base generator does not generate | occur | produce an acid, use of metal foil base materials, such as aluminum and copper, is also possible.

  The substrate is not particularly limited as long as it has necessary strength and flexibility, and preferably has the above-described light transmittance, and can be appropriately selected. Generally, a synthetic resin film is used. Synthetic resin film materials include polyester resins, polypropylene resins, polyvinyl chloride resins, fluorine resins, polystyrene resins, poly (meth) acrylic resins, cellulose resins, polycarbonate resins, polyamide resins, Known resins such as polyolefin resins, polyester resins, polyvinyl alcohol resins, polyimide resins, phenol resins, polyurethane resins and the like can be mentioned. These can be used alone or in combination of two or more. Moreover, a single layer may be sufficient and the laminated body of two or more layers may be sufficient. From the viewpoint of mechanical strength, a uniaxially stretched or biaxially stretched film is preferred. In the present invention, among the synthetic resins, it is particularly preferable to use a polyester-based resin or a polycarbonate-based resin from the viewpoints of transparency, heat resistance, dimensional stability, rigidity, flexibility, suitability for stacking, price, and the like.

  Examples of the polyester-based resin include polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate, polyarylate, polytetramethylene terephthalate, etc. Among them, from the viewpoint of ease of handling, low cost, etc. Polyethylene terephthalate is particularly preferred.

  The thickness of a base material is not specifically limited, According to a use, it can select suitably. Usually, it is about 12-250 micrometers, Preferably it is 25-250 micrometers. If it is the said range, mechanical strength is sufficient, it is hard to produce a curvature, a slack, a fracture | rupture, etc., workability | operativity is favorable, and it is also possible to supply and process in a continuous belt shape. If the thickness exceeds the above-mentioned thickness, excessive performance may increase the cost.

  The formation method of a base material is not specifically limited, For example, conventionally well-known film forming methods, such as a solution casting method, a melt extrusion method, and a calender method, can be used. Moreover, you may use the commercially available base material previously formed into a film form by the said method.

  In addition, in order to improve the wettability of the base material, one or both surfaces thereof are known such as corona discharge treatment, plasma treatment, ozone treatment, flame treatment, primer treatment, pre-heat treatment, dust removal treatment, vapor deposition treatment, alkali treatment, etc. Easy adhesion treatment may be performed.

<Peeling film>
In the pressure-sensitive adhesive sheet of the present invention, a release film may be provided on one or both surfaces of the pressure-sensitive adhesive layer made of the above-mentioned pressure-sensitive adhesive composition. In the adhesive sheet of the present invention, the release film is made of a release member having releasability, has a function of protecting the surface of the adhesive layer, and is peeled and removed during use. The release member is not particularly limited as long as it has the necessary strength and flexibility. For example, a film made of a resin such as polyethylene terephthalate, polypropylene, or polyethylene, or a foamed film thereof, silicone-based, fluorine-based, long Examples thereof include those subjected to release treatment with a release agent such as a chain alkyl group-containing carbamate. Although the thickness of a peeling film is not specifically limited, Preferably it is 12-188 micrometers.

[Method for producing adhesive sheet]
The manufacturing method of the adhesive sheet | seat using the adhesive composition of this invention is not specifically limited, A conventionally well-known method can be used. Here, the case where it is an adhesive sheet of the structure by which the adhesive layer which consists of the said adhesive composition is formed on the said peeling film is demonstrated. First, the photobase generator, the curable compound, the thermoplastic resin, and if necessary, various additives and an organic solvent are mixed and stirred, and then defoamed to form a coating solution for film formation. To prepare. Next, the entire surface of the release liquid is coated on the release-treated surface of the release film with an applicator or the like to form an adhesive layer. Then, the adhesive sheet of the present invention can be formed by drying and further laminating the release treatment surface of the release film on the adhesive layer surface.

  If the adhesive composition is solid or if the viscosity is so high that it is unsuitable for coating even if it has fluidity, it is diluted with a solvent as appropriate and dried after coating to remove the solvent. It is good to remove. In the case of a liquid that is fluid to the extent that the adhesive composition can be applied, no solvent is required.

  The method for applying the adhesive layer forming coating solution on the release film is not particularly limited, and a conventionally known method can be used. Examples of the forming method by printing include a gravure printing method, a flexographic printing method, and an offset printing method. Examples of the coating method include roll coating, reverse coating, comma coating, knife coating, die coating, and gravure coating.

  The thickness of the adhesive layer is not particularly limited and can be appropriately selected. Preferably it is 0.1-500 micrometers, More preferably, it is 1-250 micrometers. If it is the said range, adhesive physical property will be stabilized. In addition, when the thickness is less than 1 μm, the adhesiveness of the adhesive sheet may be affected by the surface unevenness of the joining member, and when it exceeds 500 μm, the curing does not proceed sufficiently or the curing time is long. There is a case.

  Although the thickness of the adhesive sheet | seat of this invention is not specifically limited, It is preferable that it is 1-500 micrometers, and it is more preferable that it is 10-300 micrometers. If it is the said range, since it has moderate softness | flexibility, handling becomes easy.

  In the pressure-sensitive adhesive sheet of the present invention, the pressure-sensitive adhesive composition is a base curable type (anion curable type), and no acid is generated. Therefore, even if the deposition target is a metal or the like, there is no risk of corrosion, and the deposition target can be selected over a wide range.

  Moreover, the adhesive sheet of the present invention does not cure even when heated to about 150 ° C. before light irradiation. Therefore, long-term storage in a sheet state is possible, and the storage period as an unused product can be extended.

(Curing)
After the above-mentioned adhesive sheet is attached to the object to be adhered, heating is performed for subsequent curing. The heating temperature is preferably 30 ° C. or higher, and more preferably 60 to 100 ° C. in consideration of the adhesive application. Moreover, if heating time is 60-100 degreeC, for example, it will harden | cure by heating about 1 hour.

  Since the adhesive sheet of the present invention is not cured until it is heated before light irradiation, the pot life can be adjusted and the workability is excellent. And after light irradiation, hardening progresses rapidly at the low temperature of 100 degrees C or less. For this reason, the adhesiveness to a location with poor heat resistance is possible. In addition, since it hardens only by heating if it is irradiated with light in advance, it is also possible to apply a substrate that does not transmit light, and there is no need to consider light transmission even in relation to the object to be deposited. It exhibits excellent effects that could not be achieved with the adhesive sheet.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention does not receive a restriction | limiting at all by these description.

<Synthesis Example 1: Base Generator A>
15 mL of methanol was placed in a 100 mL flask, and 2.00 g of potassium carbonate was added thereto. Next, 10 mL of methanol was placed in a 50 mL flask, and 2.67 g (6.2 mmol) of ethoxycarbonylmethyl (triphenyl) phosphonium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.) and 2-hydroxy-4-methoxybenzaldehyde (Tokyo Chemical Industry) 945 mg (6.2 mmol) (manufactured by Kogyo Co., Ltd.) was added and dissolved, and then the well-stirred methanol solution of potassium carbonate was slowly added dropwise. And after stirring for 3 hours, completion | finish of reaction was confirmed by TLC. Subsequently, potassium carbonate was removed by filtration, and the filtrate was concentrated under reduced pressure. After concentration, 50 mL of 1N aqueous sodium hydroxide solution was added and stirred for 1 hour. After completion of the reaction, triphenylphosphine oxide was removed by filtration, and concentrated hydrochloric acid was added dropwise to acidify the reaction solution. The precipitate was collected by filtration and washed with a small amount of chloroform to obtain 1.00 g of 2-hydroxy-4-methoxycinnamic acid. Subsequently, 619 mg (3.19 mmol) of 2-hydroxy-4-methoxycinnamic acid was dissolved in 10 mL of dehydrated tetrahydrofuran in a 100 mL three-necked flask under a nitrogen atmosphere, and 1-ethyl-3- (3- Dimethylaminopropyl) carbodiimide hydrochloride (manufactured by Tokyo Chemical Industry Co., Ltd.) 0.73 g (3.83 mmol, 1.2 eq) was added. After 30 minutes, 176 mg (1.52 mmol, 0.95 eq) of hexanediamine (manufactured by Tokyo Chemical Industry Co., Ltd.) was added, followed by stirring overnight. After completion of the reaction, the reaction solution was concentrated and dissolved in water. After extraction with chloroform, the mixture was washed with an aqueous hydrogen carbonate solution, 1N hydrochloric acid and saturated brine, dried over sodium sulfate, and concentrated to obtain 264 mg of base generator A.

<Example 1>
11 parts by mass of curable compound (trade name “Epicron EXA-835LV”, bisphenol F type epoxy resin, solid content: 100%, epoxy equivalent: 160 to 170 g / eq., Mass average molecular weight: 320 to 340, manufactured by DIC) And a curable compound (trade name “Acryset BPA-328”, acrylic rubber-dispersed bisphenol A type epoxy resin, solid content: 100%, epoxy equivalent: 220 to 240 g / eq., Mass average molecular weight: 360 to 380, acrylic Rubber: 20 phr containing, 15 parts by mass, manufactured by Nippon Shokubai Co., Ltd., curable compound (trade name “TEPIC SP”, trivalent epoxy compound having triazine nucleus in skeleton, solid content: 100%, epoxy equivalent: 105 g / eq , Mass average molecular weight: 300, about 2μ powder, manufactured by Nissan Chemical Co., Ltd.) 37 parts by mass and thermoplastic resin ( Product name “Taisan Resin SG-P3”, epoxy group-containing acrylonitrile resin, solid content: 15%, epoxy equivalent: 4760 g / eq., Mass average molecular weight: 850,000, Tg: 12 ° C., manufactured by Nagase ChemteX Corporation) 37 mass And 35 parts by mass of photobase generator A (generated base: hexanediamine) were mixed and stirred using a stirrer (product name “TK Homodisper 2.5 type”, manufactured by PRIMIX). The film formation coating liquid was prepared by defoaming.

  The film is formed on the release-treated surface of a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, film thickness: 38 μm, manufactured by Tosero). The coating solution was applied using an applicator so that the thickness after coating was 100 μm, and then dried at 100 ° C. for 20 minutes in a drying oven to form a film. Next, a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, a film thickness: 38 μm, manufactured by Tosero Co., Ltd.) is applied to the obtained film surface. The surface was affixed at room temperature using a 2 kg roller to obtain an adhesive sheet having an adhesive layer composed of the adhesive composition of Example 1.

<Example 2>
Curing compound (trade name “Epicron EXA-835LV”, bisphenol F type epoxy resin, solid content: 100%, epoxy equivalent: 160 to 170 g / eq., Mass average molecular weight: 320 to 340, manufactured by DIC) 20 parts by mass And 24 parts by mass of a thermoplastic resin (trade name “Byron 300”, polymer polyester resin, solid content: 100%, mass average molecular weight: 23000, Tg: 7 ° C., manufactured by Toyobo Co., Ltd.), and photobase generator A (Generated base: Hexanediamine) 12.4 parts by mass and 56 parts by mass of methyl ethyl ketone were mixed and stirred using a stirrer (product name “TK Homodisper 2.5”, manufactured by PRIMIX). The adhesive layer having the adhesive layer composed of the adhesive composition of Example 2 was prepared in the same manner as in Example 1 except that the film-forming coating solution was prepared by defoaming. I got a job.

<Example 3>
Curing compound (trade name “Epicron EXA-835LV”, bisphenol F type epoxy resin, solid content: 100%, epoxy equivalent: 160 to 170 g / eq., Mass average molecular weight: 320 to 340, manufactured by DIC) 20 parts by mass And thermoplastic resin (trade name “Taisan Resin SG-P3”, epoxy group-containing acrylonitrile resin, solid content: 15%, epoxy equivalent: 4750 g / eq., Mass average molecular weight: 850,000, Tg: 12 ° C., Nagase 80 parts by mass of Chemtex Co., Ltd. and 12.4 parts by mass of photobase generator A (generated base: hexanediamine) were mixed with a stirrer (product name “TK Homo Disper 2.5”), PRIMIX In the same manner as in Example 1, except that the film-forming coating solution was prepared by defoaming and mixing and stirring using Thus, an adhesive sheet having an adhesive layer was obtained.

<Example 4>
Curable compound (trade name “Epicron EXA-850S”, bisphenol A type epoxy resin, solid content: 100%, epoxy equivalent: 183 to 193 g / eq., Mass average molecular weight: 368 to 388, manufactured by DIC) 20 parts by mass And 24 parts by mass of a thermoplastic resin (trade name “Byron 300”, polymer polyester resin, solid content: 100%, mass average molecular weight: 23000, Tg: 7 ° C., manufactured by Toyobo Co., Ltd.), and photobase generator A (Generated base: hexanediamine) 10.7 parts by mass and 56 parts by mass of methyl ethyl ketone were mixed and stirred using a stirrer (product name “TK Homodisper 2.5”, manufactured by PRIMIX). The adhesive sheet having the adhesive layer composed of the adhesive composition of Example 4 was prepared in the same manner as in Example 1 except that the coating liquid for film formation was prepared by defoaming. Got.

<Comparative Example 1>
100 parts by mass of curable compound (trade name “Epicron EXA-835LV”, bisphenol F type epoxy resin, solid content: 100%, epoxy equivalent: 160 to 170 g / eq., Mass average molecular weight: 320 to 340, manufactured by DIC) And 62 parts by mass of photobase generator A (generated base: hexanediamine) were mixed and stirred using a stirrer (product name “TK. Homodisper 2.5 type”, manufactured by PRIMIX) An adhesive sheet having an adhesive layer made of the adhesive composition of Comparative Example 1 was prepared in the same manner as in Example 1, except that a film-forming coating solution was prepared by degassing. Obtained.

<Comparative Example 2>
Curing compound (trade name “Epicron EXA-835LV”, bisphenol F type epoxy resin, solid content: 100%, epoxy equivalent: 160 to 170 g / eq., Mass average molecular weight: 320 to 340, manufactured by DIC) 20 parts by mass And 24 parts by mass of a thermoplastic resin (trade name “Byron 200”, polymer polyester resin, solid content: 100%, mass average molecular weight: 17000, Tg: 67 ° C., manufactured by Toyobo Co., Ltd.), and photobase generator A (Generated base: Hexanediamine) 12.4 parts by mass and 56 parts by mass of methyl ethyl ketone were mixed and stirred using a stirrer (product name “TK Homodisper 2.5”, manufactured by PRIMIX). The adhesive having an adhesive layer made of the adhesive composition of Comparative Example 2 was prepared in the same manner as in Example 1 except that the coating liquid for film formation was prepared by defoaming. A sheet was obtained.

<Comparative Example 3>
60 parts by mass of curable compound (trade name “Epicron EXA-835LV”, bisphenol F type epoxy resin, solid content: 100%, epoxy equivalent: 160 to 170 g / eq., Mass average molecular weight: 320 to 340, manufactured by DIC) And 10 parts by mass of a thermoplastic resin (trade name “Byron 300”, polymer polyester resin, solid content: 100%, mass average molecular weight: 23000, Tg: 7 ° C., manufactured by Toyobo Co., Ltd.), and photobase generator A (Generated base: Hexanediamine) 37.2 parts by mass and 35 parts by mass of methyl ethyl ketone were mixed and stirred using a stirrer (product name “TK Homodisper 2.5”, manufactured by PRIMIX). In the same manner as in Example 1 except that a film-forming coating solution was prepared by defoaming, an adhesive layer having an adhesive layer composed of the adhesive composition of Comparative Example 3 was used. I got a job.

[Check glue residue]
One release film of the adhesive sheet having the adhesive layer composed of the adhesive compositions of Examples 1 to 4 and Comparative Examples 1 to 3 is peeled off, and the presence or absence of adhesive residue on the release film is visually observed. Confirmed. The results are shown in Table 1. The evaluation criteria are as follows. ○: No adhesive residue, Δ: Slight adhesive residue, ×: Adhesive residue remaining.

  As shown in Table 1, in the adhesive sheet having the adhesive layer composed of the adhesive compositions of Examples 1 to 4 and Comparative Example 2, no adhesive residue was observed, In the adhesive sheet having an adhesive layer composed of the adhesive compositions of Comparative Examples 1 and 3, considerable adhesive residue was observed.

<Example 5>
Same as Example 1 on the release treatment surface of a release film (trade name: SP-PET-03, polyester film having a release treatment with a silicone release agent on one side, film thickness: 38 μm, manufactured by Tosero) The film-forming coating solution was applied using an applicator so that the thickness after coating was 100 μm, and then dried in a drying oven at 100 ° C. for 20 minutes to form a film. Next, a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, a film thickness: 38 μm, manufactured by Tosero Co., Ltd.) is applied to the obtained film surface. The surfaces were laminated to obtain an adhesive sheet having an adhesive layer composed of the adhesive composition of Example 5.

<Example 6>
Same as Example 2 on the release treatment surface of a release film (trade name: SP-PET-03, polyester film having a release treatment with a silicone release agent on one side, film thickness: 38 μm, manufactured by Tosero) The film-forming coating solution was applied using an applicator so that the thickness after coating was 100 μm, and then dried in a drying oven at 100 ° C. for 20 minutes to form a film. Next, a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, a film thickness: 38 μm, manufactured by Tosero Co., Ltd.) is applied to the obtained film surface. The surfaces were laminated to obtain an adhesive sheet having an adhesive layer composed of the adhesive composition of Example 6.

<Example 7>
Same as Example 3 on the release treatment surface of a release film (trade name: SP-PET-03, polyester film having a release treatment with a silicone release agent on one side, film thickness: 38 μm, manufactured by Tosero) The film-forming coating solution was applied using an applicator so that the thickness after coating was 100 μm, and then dried in a drying oven at 100 ° C. for 20 minutes to form a film. Next, a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, a film thickness: 38 μm, manufactured by Tosero Co., Ltd.) is applied to the obtained film surface. The surfaces were laminated to obtain an adhesive sheet having an adhesive layer composed of the adhesive composition of Example 7.

<Example 8>
Same as Example 4 on the release treatment surface of a release film (trade name: SP-PET-03, polyester film having a release treatment with a silicone release agent on one side, film thickness: 38 μm, manufactured by Tosero) The film-forming coating solution was applied using an applicator so that the thickness after coating was 100 μm, and then dried in a drying oven at 100 ° C. for 20 minutes to form a film. Next, a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, a film thickness: 38 μm, manufactured by Tosero Co., Ltd.) is applied to the obtained film surface. The surfaces were laminated to obtain an adhesive sheet having an adhesive layer composed of the adhesive composition of Example 8.

<Comparative Example 4>
Same as Comparative Example 1 on the release-treated surface of a release film (trade name: SP-PET-03, polyester film having a release treatment with a silicone release agent on one side, film thickness: 38 μm, manufactured by Tosero) The film-forming coating solution was applied using an applicator so that the thickness after coating was 100 μm, and then dried in a drying oven at 100 ° C. for 20 minutes to form a film. Next, a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, a film thickness: 38 μm, manufactured by Tosero Co., Ltd.) is applied to the obtained film surface. The surfaces were laminated to obtain an adhesive sheet having an adhesive layer composed of the adhesive composition of Comparative Example 4.

<Comparative Example 5>
Same as Comparative Example 2 on the release-treated surface of a release film (trade name: SP-PET-03, polyester film having a release treatment with a silicone release agent on one side, film thickness: 38 μm, manufactured by Tosero) The film-forming coating solution was applied using an applicator so that the thickness after coating was 100 μm, and then dried in a drying oven at 100 ° C. for 20 minutes to form a film. Next, a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, a film thickness: 38 μm, manufactured by Tosero Co., Ltd.) is applied to the obtained film surface. The surfaces were laminated to obtain an adhesive sheet having an adhesive layer composed of the adhesive composition of Comparative Example 5.

<Comparative Example 6>
Same as Comparative Example 3 on the release-treated surface of a release film (trade name: SP-PET-03, polyester film having a release treatment with a silicone release agent on one side, film thickness: 38 μm, manufactured by Tosero) The film-forming coating solution was applied using an applicator so that the thickness after coating was 100 μm, and then dried in a drying oven at 100 ° C. for 20 minutes to form a film. Next, a release film (trade name: SP-PET-03, a polyester film having a release treatment with a silicone-based release agent on one side, a film thickness: 38 μm, manufactured by Tosero Co., Ltd.) is applied to the obtained film surface. The surfaces were laminated to obtain an adhesive sheet having an adhesive layer composed of the adhesive composition of Comparative Example 6.

[Measurement of shear adhesive strength]
After cutting the adhesive sheet which has an adhesive layer which consists of adhesive composition of Examples 5-8 and Comparative Examples 4-6 into 10 mm x 10 mm, the peeling film of one side is peeled off, and glass It bonded together to the board (width 15mm x length 50mm x thickness 3mm). Next, the release film on the other side is peeled off to expose the adhesive surface, and then an ultraviolet irradiation device (product name “DRE-10 / 12QN”, using an H bulb, manufactured by Fusion UV Systems Japan) is applied to the surface. Then, ultraviolet rays were irradiated so that the light intensity was 2000 mJ in the wavelength region of 300 to 370 nm. Then, the glass plate of the same size as the above was pressure-bonded to the adhesive surface irradiated with ultraviolet rays using a 2 kg roller. And after heating at 100 degreeC in a drying oven for 1 hour, it hardened | cured for 1 day and measured on the conditions (based on JISK6850) of measurement temperature 23 degreeC and a pulling speed of 50 mm / min. The results are shown in Table 2.

  As shown in Table 2, the adhesive sheet having an adhesive layer composed of the adhesive compositions of Examples 5 to 8 showed good adhesive strength. On the other hand, the adhesive sheet having the adhesive layer composed of the adhesive compositions of Comparative Examples 4 and 6 has adhesive residue on the release film and good adhesiveness to the glass plate. The state of transition to the adhesive layer was not achieved. Moreover, the adhesive sheet which has the adhesive layer which consists of an adhesive composition of the comparative example 5 was a state which does not have adhesiveness with respect to a glass plate. This is presumably because the Tg of the polyester resin is high.

Claims (4)

A base generator represented by the following general formula (I) that generates a base by heating after light irradiation, a curable compound having at least one epoxy group in the molecule, and a glass transition temperature (Tg) of −10 A thermoplastic resin having a temperature of -30 ° C,
Content of the said thermoplastic resin is 37-80 mass parts with respect to 100 mass parts of total amounts of the said sclerosing | hardenable compound and this thermoplastic resin, The adhesive composition characterized by the above-mentioned.

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a monovalent organic group. R ¹ and R ² may combine with each other to form a cyclic structure. ^At least one of R ¹ and R ² represents a monovalent organic group, R ^{3 to} R ⁶ each independently represents a hydrogen atom, a halogen atom or an organic group, and R ^{3 to} R ⁶ represent 2 of them. Two or more may combine to form a cyclic structure.)   The pressure-sensitive adhesive composition according to claim 1, wherein the base generator generates a base having at least two amino groups.   The adhesive composition according to claim 1 or 2, wherein the curable compound is an epoxy resin. An adhesive sheet having at least an adhesive layer comprising the adhesive composition according to any one of claims 1 to 3 .