WO2024058117A1

WO2024058117A1 - Resin material and resin composition

Info

Publication number: WO2024058117A1
Application number: PCT/JP2023/033033
Authority: WO
Inventors: 祐樹宮本; 秀一近藤; 晃一斉藤
Original assignee: 株式会社レゾナック
Priority date: 2022-09-12
Filing date: 2023-09-11
Publication date: 2024-03-21

Abstract

The present disclosure relates to a resin material which contains a compound A that has a (meth)acryloyl group, a compound B that has two or more thiol groups, and photoradical generator that has a 5% weight loss temperature of 200°C or more, wherein: the compound A contains a compound A-1 that has three or more (meth)acryloyl groups; and at least one of the compound A and the compound B has a disulfide bond.

Description

Resin materials and resin compositions

The present disclosure relates to resin materials and resin compositions.

Photosoftening compositions that can be softened by light irradiation are used for various purposes. For example, Patent Document 1 discloses an image forming apparatus including a recording member having a resin layer made of a photo-softening composition.

Japanese Unexamined Patent Publication No. 11-190883

Resin compositions exhibiting photosoftening properties are expected to be applied as adhesives and coating materials that provide easy peelability. The molecular structure was designed to ensure photosoftening, but there was room for improvement in terms of heat resistance. It is presumed that a photosoftening composition that can withstand heating processes can expand the range of application processes for adhesives, coating materials, and the like.

An object of the present disclosure is to provide a resin material that provides a resin composition that has excellent heat resistance and exhibits photosoftening properties. An object of the present disclosure is to provide a resin composition that exhibits excellent heat resistance and photosoftening properties.

In some aspects, the present disclosure provides the following [1] to [6].
[1] Contains a compound A having a (meth)acryloyl group, a compound B having two or more thiol groups, and a photoradical generator having a 5% weight loss temperature of 200°C or higher, wherein the compound A is , a resin material comprising a compound A-1 having three or more (meth)acryloyl groups, wherein at least one of the compound A and the compound B has a disulfide bond in the molecule.
[2] The resin material according to [1], wherein the compound A further contains a compound A-2 having two (meth)acryloyl groups.
[3] The radical generator is a compound that gives benzoyl radicals upon light irradiation, and the ratio of the number of moles of the benzoyl radical to the number of moles of the compound A-1 is 21/20 or more, [1] or The resin material according to [2].
[4] Contains a reaction product of a compound A having a (meth)acryloyl group and a compound B having two or more thiol groups, and a photoradical generator having a 5% weight loss temperature of 200°C or higher. A resin composition, wherein the compound A includes a compound A-1 having three or more (meth)acryloyl groups, and at least one of the compound A and the compound B has a disulfide bond in the molecule.
[5] The resin composition according to [4], wherein the compound A further contains a compound A-2 having two (meth)acryloyl groups.
[6] The radical generator is a compound that gives benzoyl radicals upon light irradiation, and the ratio of the number of moles of the benzoyl radical to the number of moles of the compound A-1 is 21/20 or more, [4] or The resin composition according to [5].

According to the present disclosure, it is possible to provide a resin material that provides a resin composition that has excellent heat resistance and exhibits photosoftening properties. According to the present disclosure, it is possible to provide a resin composition that has excellent heat resistance and exhibits photosoftening properties.

It is a figure showing the test piece produced for adhesion strength evaluation. 1 is a graph showing the results of photoresponsive evaluation of storage modulus G' of a resin composition. It is a graph showing the photoresponsive evaluation results of tan δ of the resin composition. 3 is a photograph showing the appearance of a resin composition after light irradiation, in which (A) shows the results of Example 1, (B) shows the results of Example 2, and (C) shows the results of Example 3. It is a graph showing adhesive force measurement results. The results of storage modulus, loss modulus, and tan δ at high temperatures of Example 3 and Comparative Example 1 are shown, (A) shows the results of Example 3, and (B) shows the results of Comparative Example 1. It is a photograph showing the appearance of the shear test piece after adhesion strength measurement, (a) shows the appearance of the shear test piece before measurement, (b) shows the peeling state of the sample that has not been exposed to light, and (c) shows the peeling state of the sample that has not been exposed to light. The peeled state after irradiation is shown, and (d) shows the appearance of the shear test piece shown in (c) after cleaning.

Hereinafter, embodiments of the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments.

In this specification, the term "process" is used not only to refer to an independent process, but also to include any process that achieves the intended effect even if it cannot be clearly distinguished from other processes. It will be done. A numerical range indicated using "~" indicates a range that includes the numerical values written before and after "~" as the minimum and maximum values, respectively.

In this specification, the content of each component in the resin material or resin composition means the total amount of the plurality of substances, unless otherwise specified, when there are multiple substances corresponding to each component. Unless otherwise specified, the illustrated materials may be used alone or in combination of two or more.

In the numerical ranges described step by step in this specification, the upper limit or lower limit of the numerical range of one step may be replaced with the upper limit or lower limit of the numerical range of another step. In the numerical ranges described in this specification, the upper limit or lower limit of the numerical range may be replaced with the value shown in the Examples. "A or B" may include either A or B, or may include both. In this specification, a "(meth)acryloyl group" is a methacryloyl group or an acryloyl group. In this specification, "weight average molecular weight" and "number average molecular weight" are polystyrene equivalent values determined by gel permeation chromatography (GPC) using a standard polystyrene calibration curve. As used herein, "room temperature" means 25±10°C.

As used herein, "photosoftening" means the property of softening upon irradiation with light. The softening property includes, for example, a decrease in elastic modulus and an increase in loss tangent (tan δ). In this specification, "softened resin composition" refers to a resin composition in which the elastic modulus has decreased, a loss tangent (tan δ) has increased, etc., based on the resin composition before light irradiation. means. A resin composition exhibiting photosoftening property means a composition that gives a gel-like material or a liquid material by being softened by light irradiation.

The resin material according to the present embodiment contains a compound A having a (meth)acryloyl group, a compound B having two or more thiol groups, and a photoradical generator having a 5% weight loss temperature of 200°C or higher. do. At least one of Compound A and Compound B has a disulfide bond (-SS-) in the molecule.

Compound A includes compound A-1 having three or more (meth)acryloyl groups. Compound A-1 is a compound having three or more groups in one molecule of one or more types selected from the group consisting of methacryloyl groups and acryloyl groups. The upper limit of the number of (meth)acryloyl groups in compound A-1 may be, for example, 10 or less, 8 or less, 6 or less, or 4 or less per molecule. Compound A-1 may be a compound having three (meth)acryloyl groups.

The molecular weight or weight average molecular weight of compound A-1 may be 150 or more, 500 or more, or 1000 or more, and may be 50000 or less, 10000 or less, or 2000 or less.

Compound A-1 is, for example, a compound having a trimethylolpropane skeleton and three or more (meth)acryloyl groups, or a compound having a pentaerythritol skeleton and three or more (meth)acryloyl groups. and a compound having an isocyanurate skeleton and three or more (meth)acryloyl groups.

Compound A-1 having a trimethylolpropane skeleton may be, for example, a compound represented by the following formula (a1).

In formula (a1), R ¹ represents a hydrogen atom or a methyl group, and L ¹ represents an alkylene group. n1, n2 and n3 each independently represent an integer of 0 or 1 or more. A plurality of R ¹ 's may be the same or different. The number of carbon atoms in the alkylene group represented by L ¹ may be 2 or more, 10 or less, 6 or less, or 3 or less. The alkylene group represented by L ¹ may be, for example, an ethylene group (-CH ₂ -CH ₂ -). When there is a plurality of L ¹ 's, each may be the same or different. The sum n1+n2+n3 of n1, n2, and n3 may be, for example, 0 or more, 6 or more, 27 or less, 20 or less, or 9.

Commercially available products of compound A-1 having three (meth)acryloyl groups include FANCRYL FA-133A (manufactured by Showa Denko Materials Co., Ltd.), FA-132A, FA-137A, FA-133M, FA- 137M (all manufactured by Showa Denko Materials Co., Ltd.), NK Ester A-TMPT, NK Ester A-TMPT-9EO, NK Ester AT-20E, NK Ester A-GLY-3E, NK Ester A-GLY-9E, NK Ester A-GLY-20E, NK Ester A-9300 (all manufactured by Shin-Nakamura Chemical Co., Ltd.) TMPTA, EBECRYL160S, OTA480 (all manufactured by Daicel Ornyx Co., Ltd.) Viscoat #295, Viscoat #300 (all manufactured by Osaka Organic Co., Ltd.) Chemical Industry Co., Ltd.), EBECRYL4513, EBECRYL8465, EBECRYL9260, EBECRYL8701, KRM8667, and KRM8296 (all manufactured by Daicel Ornyx Corporation). Commercially available compounds A-1 having four or more (meth)acryloyl groups include EBECRYL4265, EBECRYL4587, EBECRYL4666, EBECRYL8210, EBECRYL8606, EBECRYL1290, EBECRYL5129, EBECRYL8254, EBECRYL RYL8301R, KRM8200, KRM8904, KRM8452, EBECRYL220 (all Daicel Ornyx Co., Ltd.), NK Ester A-TMMT, NK Ester ATM-35E, NK Ester AD-TMP, NK Ester A-DPH, NK Ester A-9550, NK Ester A-DPH-12E, and NK Ester TPOA-50 (all manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), etc.

Compound A may further contain compound A-2 having two (meth)acryloyl groups. Compound A-2 is a compound having two of one or more groups selected from the group consisting of methacryloyl groups and acryloyl groups. Compound A-2 further contains a linking group that links the two (meth)acryloyl groups.

The molecular weight or weight average molecular weight of compound A-2 may be 150 or more, 500 or more, or 1000 or more, and may be 50000 or less, 10000 or less, or 2000 or less.

Compound A-2 may be, for example, a compound represented by the following formula (a2).

In formula (a2), R ² represents a hydrogen atom or a methyl group. L ² represents an alkylene group. A plurality of R ² 's may be the same or different. The number of carbon atoms in the alkylene group represented by L ² may be 2 or more, 10 or less, 6 or less, or 3 or less. The alkylene group represented by L ² may be, for example, an ethylene group (-CH ₂ -CH ₂ -). m represents an integer of 1 or more. m may be 2 or more or 3 or more. The upper limit of m may be, for example, 10 or less, 8 or less, 6 or less, or 5 or less. When there is a plurality of ^L2 's, each of them may be the same or different.

Commercially available products of compound A-2 include, for example, Fancryl FA-220 (manufactured by Showa Denko Materials Co., Ltd.), NK Ester HD-N, NK Ester NOD-N, NK Ester DOD-N, NK Ester NPG, and NK Ester. Ester 701, NK Ester 2G, NK Ester 3G, NK Ester 4G, NK Ester 9G, NK Ester 14G, NK Ester 23G, NK Ester 9PG, NK Ester DCP, NK Ester BPE-80N, NK Ester BPE-100, NK Ester BPE -200, NK Ester BPE-500, NK Ester BPE-900, NK Ester BPE-1300N, NK Ester A-HD-N, NK Ester A-NOD-N, NK Ester A-DOD-N, NK Ester A-NPG -N, NK Ester 701A, NK Ester A-200, NK Ester A-400, NK Ester A-600, NK Ester A-1000, NK Ester APG-200, NK Ester APG-400, NK Ester APG-700, NK Ester A-PTMG65, NK Ester A-DCP, NK Ester ABE-300, NK Ester A-BPE-4, NK Ester A-BPE-10, NK Ester A-BPE-20 (all manufactured by Shin-Nakamura Chemical Co., Ltd.) ), EBECRYL210, EBECRYL230, EBECRYL270, EBECRYL4858, EBECRYL8402, EBECRYL8804, EBECRYL8807, EBECRYL9270, EBECRYL8191, Shiko ^TM UV-2000B, Shiko TM UV-3000B, Shiko ^TM UV-3200B, Shiko ^TM UV-3300B, Shiko ^TM UV ^- 3310B, Examples include Shiko ^TM UV-3500BA, Shiko ^TM UV-3520EA, Shiko ^TM UV-3700B, and Shiko ^TM UV-6640B (all manufactured by Mitsubishi Chemical Corporation).

The content of compound A (total content of compound A-1 and compound A-2) may be 1% by mass or more, 3% by mass or more, or 5% by mass or more, based on the total amount of the resin material, It may be 99% by weight or less, 97% by weight or less, or 95% by weight or less.

The content of compound A-1 may be 1% by mass or more, 3% by mass or more, or 5% by mass or more, and 90% by mass or less, 50% by mass or less, or 15% by mass, based on the total amount of the resin material. % or less.

The content of compound A-2 may be 1% by mass or more, 3% by mass or more, or 5% by mass or more, and 99% by mass or less, 97% by mass or less, or 95% by mass, based on the total amount of the resin material. % or less.

The ratio of the number of moles of compound A-1 to the total number of moles of compound A (the total number of moles of compound A-1 and compound A-2) is 0.05 or more, 0.1 or more, or 0.2 or more. It may be 0.5 or less, 0.4 or less, or 0.3 or less. When the ratio of the number of moles of compound A-1 to the total number of moles of compound A is 0.5 or less, the photosoftening property is further improved. When the ratio of the number of moles of Compound A-1 to the total number of moles of Compound A is 0.05 or more, thermoplasticity is further reduced and mechanical properties at high temperatures are further improved.

When compound A has a disulfide bond in the molecule, the number of disulfide bonds in compound A-1 or compound A-2 may be, for example, 1 to 1000 or 4 to 50.

Compound B is a compound having two or more thiol groups (-SH) in one molecule. The upper limit of the number of thiol groups of compound B per molecule may be, for example, 10 or less, 8 or less, 6 or less, 4 or less, or 3 or less. Compound B may be a compound having two thiol groups.

When compound B has a disulfide bond in the molecule, the number of disulfide bonds in compound B may be, for example, 1 to 1000 or 4 to 50.

The molecular weight or weight average molecular weight of compound B may be 100 or more, 1000 or more, or 3000 or more, and may be 50000 or less, 30000 or less, or 10000 or less.

Compound B has a linear molecular chain and a terminal group, and may be a compound (for example, a polymer or oligomer) having a disulfide bond in the molecular chain. In this case, the terminal group in compound B may be a thiol group. When Compound B is such a compound, it becomes even easier to form a cured product having excellent photosoftening properties. The molecular chain in compound B may contain a disulfide bond and a polyether chain, or may consist of a disulfide bond and a polyether chain.

Compound B may be, for example, a compound (compound (1)) represented by formula (1): HS-(A-S-S) _p -A-SH. In the formula, A represents a polyether chain. A plurality of A's may be the same or different. p represents an integer of 1 or more. p may be, for example, 1 or more, 4 or more, and 1000 or less. Compound B may be a chain-extended compound of compound (1).

The polyether chain as A may be, for example, a polyoxyalkylene chain. The polyether chain as A may be, for example, a group represented by -A ¹ -O-A ² -O-A ³ -. A ¹ to A ³ may each independently be an alkylene group, and may be an alkylene group having 1 to 2 carbon atoms (eg, methylene group, ethylene group). Examples of the polyether chain as A include -CH ₂ CH ₂ -O-CH ₂ -O-CH ₂ CH ₂ -.

Commercially available products of Compound B include, for example, Thiokol LP series (dithiol having a disulfide bond, manufactured by Toray Fine Chemical Co., Ltd.). Compound B may be used alone or in combination of two or more. Compound B can also be obtained by converting the reactive functional group of a starting compound having a reactive functional group and a disulfide bond at its terminal into a thiol group. Examples of the reactive functional group in the raw material compound include a carboxy group and a hydroxy group. Examples of the raw material compound having a reactive functional group and a disulfide bond at the terminal include 3,3'-dithiodipropionic acid, dithiodiethanol, and cystamine.

The content of compound B may be 1% by mass or more, 3% by mass or more, 5% by mass or more, 30% by mass or more, or 50% by mass or more, and 99% by mass or less, based on the total mass of the resin material. , 97% by mass or less, or 95% by mass or less.

The ratio of the number of moles of the thiol group in compound B to the number of moles of the (meth)acryloyl group in compound A may be, for example, 0.90 or more, or 0.95 or more, and 1.1 or less, or It may be 1.05 or less. When the ratio of the number of moles of thiol group in compound B to the number of moles of (meth)acryloyl group in compound A is within the above-mentioned range, the decrease in photosoftening property is further suppressed, and the resin composition is Deterioration in storage stability is also further suppressed.

A photo-radical generator is a component that generates radicals when irradiated with light. As the photoradical generator, for example, a component used as a photopolymerization initiator can be used. Photo-radical generators include hydrogen-extracting photo-radical polymerization initiators that generate radicals by extracting hydrogen from other molecules when irradiated with light, and intramolecular photo-radical polymerization initiators that generate two radicals by photo-cleaving itself upon irradiation with light. Examples include cleavable photoradical polymerization initiators. The photo-radical generator may be an intramolecularly cleavable photo-radical polymerization initiator since it provides better photo-softening properties.

Examples of the hydrogen abstraction type photoradical generator include hexaarylbisimidazole (HABI) compounds, benzophenone compounds, thioxanthone compounds, fluorenone compounds, α-diketone compounds, and the like.

Intramolecular cleavage type photoradical generators include benzyl ketal photoradical generators, α-aminoalkylphenone photoradical generators, α-hydroxyalkylphenone photoradical generators, and α-hydroxyacetophenone photoradical generators. , acylphosphine oxide photoradical generators, and the like.

The 5% weight loss temperature of the photoradical generator is 200°C or higher. The 5% weight loss temperature is the temperature at which the mass of the sample decreases by 5% from the initial value in thermogravimetric analysis in which changes in the mass of the sample are measured while increasing the temperature. The 5% weight loss temperature of the photoradical generator may be 210° C. or higher, 220° C. or higher, 230° C. or higher, 240° C. or higher, or 250° C. or higher, since the heat resistance of the resin composition is further improved. The temperature may be 340°C or lower, 330°C or lower, 320°C or lower, 310°C or lower, or 300°C or lower.

Examples of the photoradical generator having a 5% weight loss temperature of 200°C or higher include 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one. (5% weight loss temperature: 204°C), 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propan-1-one (5% weight loss temperature: 220°C), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (5% weight loss temperature: 248°C), 2-dimethylamino-2 -(4-Methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one (5% weight loss temperature: 248°C), bis(2,4,6-trimethylbenzoyl) -phenylphosphine oxide (5% weight loss temperature: 241°C), 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (5% weight loss temperature: 253°C), and polymers thereof.

The photo-radical generator is an α-aminoalkylphenone-based photo-radical generator from the viewpoint of further suppressing curing inhibition, further suppressing the decrease in storage modulus during curing, and solubility in resin components. and may be 2-(dimethylamino)-2-(4-methylbenzyl)-1-[4-morpholin-4-yl-phenyl)butan-1-one.

The photo-radical generator has even better photo-softening properties, so it may be a compound that generates two or more monoradicals per molecule of the photo-radical generator when irradiated with light, but does not generate diradicals. Examples of such photoradical generators include 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, and 2-hydroxy-2-methyl-1-phenyl. -Propan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy -2-Methyl-1-propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-dimethylamino-2-(4-methyl-benzyl) -1-(4-morpholin-4-yl-phenyl)-butan-1-one, and 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide.

The photoradical generator may be a compound that provides benzoyl radicals upon irradiation with light. A compound that provides benzoyl radicals upon irradiation with light is a compound that is cleaved by photoreaction to produce benzoyl radicals. Examples of compounds that give benzoyl radicals when irradiated with light include 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, and 2-hydroxy-2-methyl-1- Phenyl-propan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2- Hydroxy-2-methyl-1-propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-dimethylamino-2-(4-methyl-benzyl )-1-(4-morpholin-4-yl-phenyl)-butan-1-one, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, and bis(2,4,6-trimethylbenzoyl)- Examples include phenylphosphine oxide.

The content of the photoradical generator may be 3% by mass or more, 5% by mass or more, or 10% by mass or more, and 30% by mass or less, 20% by mass or less, or 15% by mass, based on the total amount of the resin material. % or less.

The ratio of the number of moles of the photoradical generator to the number of moles of compound A-1 is 1 or more, 1.5 or more, 2 or more, 3 or more, 5 or more, 8 or more, 10 or more, since the photosoftening property is further improved. or more, 12 or more, 14 or more, or 16 or more. The ratio of the number of moles of the photoradical generator to the number of moles of compound A-1 is, for example, 20 or less, 18 or less, 16 or less, 14 or less, 12 or less, 10 or less, 8 or less, 6 or less, 4 or less, or 2 It may be the following.

The ratio of the number of moles of the photoradical generator to the number of moles of compound B is 0.2 or more, 0.5 or more, 0.7 or more, 0.9 or more, or 1. It may be 1 or more. The ratio of the number of moles of the photoradical generator to the number of moles of compound B may be 3.0 or less, 2.0 or less, or 1.5 or less.

The ratio of the number of moles of benzoyl radical to the number of moles of compound A-1 may be 21/20 or more, since the photosoftening property is further improved. The ratio of the number of moles of benzoyl radical to the number of moles of compound A-1 may be 2 or more, 3 or more, or 4 or more, since the photosoftening property is further improved. The ratio of the number of moles of benzoyl radical to the number of moles of compound A-1 may be, for example, 20 or less, 15 or less, 12 or less, 10 or less, 8 or less, 6 or less, 4 or less, or 2 or less.

The resin material may further contain a catalyst. By further including a catalyst, the reaction between compound A and compound B is further promoted. Examples of the catalyst include amine compounds and phosphorus compounds.

The amine compound may be, for example, a tertiary amine compound or a secondary amine compound. Examples of amine compounds include dicyandiamide, trimethylamine, triethylamine, tripropylamine, tributylamine, tri-n-octylamine, dimethylethylamine, dimethylpropylamine, dimethylbutylmian, dimethyl-n-octylamine, 1,4-diazabicyclo [2.2.2] Octane, 1,8-diazabicyclo[5.4.0]undec-7-ene, benzyldimethylamine, 4-methyl-N,N-dimethylbenzylamine, 2,4,6-tris (dimethylaminomethyl)phenol and 4-dimethylaminopyridine.

The catalyst is 1,8-diazabicyclo[5.4.0]undec-7-ene or a salt thereof, as it facilitates rapid curing at room temperature and makes it easier to control open time. It may be a phosphorus compound.

The content of the catalyst may be 0.02% by mass or more, 0.1% by mass or more, or 1% by mass or more, and 3% by mass or less, 2.5% by mass or less, based on the total amount of the resin material. Or it may be 2% by mass or less.

The resin material may further contain components (other components) that do not correspond to the compound A, the compound B, the photoradical generator, and the catalyst. Other ingredients include, for example, tackifiers such as plasticizers and tackifiers, adhesion improvers such as antioxidants, leuco dyes, sensitizers, and coupling agents, polymerization inhibitors, light stabilizers, and quenchers. Additives include foaming agents, fillers, chain transfer agents, thixotropy agents, flame retardants, mold release agents, surfactants, lubricants, antistatic agents, and the like. Known additives can be used as these additives. When the resin material contains other components, the total amount of the other components is 0 to 95% by mass, 0.01 to 50% by mass, or 0.1 to 10% by mass based on the total amount of the resin material. It may be %.

The resin material may be used as a varnish made of a resin material diluted with a solvent. Examples of the solvent include aromatic hydrocarbons such as toluene, xylene, mesitylene, cumene, and p-cymene; aliphatic hydrocarbons such as hexane and heptane; cyclic alkanes such as methylcyclohexane; and tetrahydrofuran and 1,4-dioxane. Cyclic ethers; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone; esters such as methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolactone; Examples include carbonic acid esters such as ethylene carbonate and propylene carbonate; amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone (NMP). The solid content in the varnish, that is, the total content other than the solvent in the varnish, is 10 to 95% by mass, or 15 to 70% by mass, or 20 to 50% by mass, based on the total mass of the varnish. It's good to be there.

The resin material can be prepared, for example, by a method that includes a step of mixing or kneading the above-mentioned components. Mixing and kneading can be carried out using an appropriate combination of dispersing machines such as a conventional stirrer, a sieve machine, a three-roll mill, a ball mill, and a bead mill.

The resin composition according to the present embodiment contains a reaction product of Compound A and Compound B, and a photoradical generator whose 5% weight loss temperature is 200° C. or higher. The resin composition according to this embodiment is a cured product of the resin material described above. Specific embodiments of Compound A, Compound B, and the photoradical generator are the same as those described for the resin material.

Examples of the method for obtaining the resin composition include the method of reacting the resin materials described above. The reaction temperature of the resin material may be, for example, 0 to 200°C, 30 to 150°C, or 60 to 100°C. The time for maintaining the above reaction temperature may be, for example, 0.1 to 168 hours, 72 hours or less, 24 hours or less, 12 hours or less, 6 hours or less, 4 hours or less, 3 hours or less, or 2 hours or less. It may be.

More specifically, the reaction product of Compound A and Compound B is formed by a Michael addition reaction between the (meth)acryloyl group in Compound A and the thiol group in Compound B.

The reaction product of compound A and compound B has a structure represented by formula (I): *-C(=O)-CHR-CH ₂ -S-* and a disulfide bond. In formula (I), R represents a hydrogen atom or a methyl group, and * represents a bond. Disulfide bonds may be present in the main chain and/or side chain of the reaction product. A disulfide bond may be present in the main chain of the reaction product since the photosoftening property is further improved.

The reaction product of compound A and compound B may include a compound having a structure represented by the following formula (x1).

In formula (x1), R ¹ , L ¹ , n1, n2 and n3 have the same meanings as in formula (a1), A and p have the same meanings as in formula (1), and * indicates a bond. In formula (x1), a plurality of R ¹ , L ¹ , A and p may be the same or different from each other.

The reaction product of compound A and compound B may include a compound having a structure represented by the following formula (x2).

In formula (x2), R ² , L ² , and m have the same meanings as in formula (a2), A and p have the same meanings as in formula (1), and * indicates a bond. In formula (x2), a plurality of R ² , A and p may be the same or different.

The number average molecular weight Mn of the resin composition may be 1000 or more, 2000 or more, 3000 or more, 5000 or more, 6000 or more, or 6500 or more, and may be 200000 or less, 100000 or less, or 50000 or less.

The weight average molecular weight Mw of the resin composition is 1,000 or more, 3,000 or more, 5,000 or more, 10,000 or more, 15,000 or more, 20,000 or more, 25,000 or more, 30,000 or more, or 40,000 or more, and 1,000,000 or less, 400,000 or less, or 100,000 or less.

The storage modulus G' of the resin composition may be 1 kPa or more, 10 kPa or more, or 100 kPa or more, and may be 100000 kPa or less, 10000 kPa or less, or 2000 kPa or less.

The storage modulus G' of the resin composition can be measured by the method described in the Examples below.

The 5% weight loss temperature T _d5% of the resin composition may be 210°C or higher, 220°C or higher, 230°C or higher, 240°C or higher, or 250°C or higher, since the resin composition has better heat resistance. , 310°C or less, 300°C or less, 290°C or less, 280°C or less, or 270°C or less. The 5% weight loss temperature T _d5% of the resin composition can be measured by the method described in the Examples below.

The shear adhesive strength of the resin composition at 25°C may be 10 N/cm ² or more, 20 N/cm ² or more, or 50 N/cm ² or more, and the shear adhesive strength of the resin composition at 100°C may be 10 N/cm 2 or more, or 50 N/cm 2 or more. cm ² or more, or 20 N/cm ² or more, and 50 N/cm ² or less. The shear adhesive strength of the resin composition can be measured by the method described in Examples below.

The resin composition has the property of being softened by light irradiation. The light used for light irradiation may be, for example, light containing light with a wavelength of 365 nm or 405 nm. By irradiating with such light, the resin composition can be softened. The exposure amount of light irradiation may be, for example, 1000 mJ/cm ² or more. In this specification, the exposure amount means the product of illuminance (mW/cm ² ) and irradiation time (seconds). The light may be irradiated directly onto the object to be irradiated, or may be irradiated through glass or the like. The light source used for light irradiation is not particularly limited, and includes, for example, an LED lamp, a mercury lamp (low pressure, high pressure, ultra-high pressure, etc.), a metal halide lamp, an excimer lamp, a xenon lamp, and the like. Among these, the light source used for light irradiation may be an LED lamp, a mercury lamp, or a metal halide lamp.

By irradiating the resin composition with light, the photoradical generator in the resin composition cleaves the disulfide bond (-SS-) in the reaction product of compound A and compound B. As a result, crosslinking of the reaction product of Compound A and Compound B is reduced, or the molecular weight of the reaction product of Compound A and Compound B is lowered and softened. Since the resin composition is softened by light irradiation, it can also be called a photo-softening composition.

The number average molecular weight Mn of the resin composition (photosoftened product) after light irradiation may be 100,000 or less, 50,000 or less, 20,000 or less, 10,000 or less, 1,000 or more, 3,000 or more, 5,000 or more, or 5,500 or more. .

The weight average molecular weight Mw of the photosoftened material may be 300,000 or less, 150,000 or less, 60,000 or less, 60,000 or less, or 30,000 or less, 10,000 or more, or 15,000 or more It may be.

The Mn and Mw of the photosoftened product can be measured by the method described in the Examples below.

The storage modulus G' of the photosoftened material is usually lower than the storage modulus G' of the resin composition. The storage modulus G' of the photosoftened material may be 8 kPa or less, 5 kPa or less, 3 kPa or less, or 1 kPa or less, and may be 0.001 kPa or more, or 0.005 kPa or more.

The loss modulus G'' of the photosoftened material is 0.10 kPa or more, 0.20 kPa or more, 0.30 kPa or more, 0.50 kPa or more, 0.70 kPa or more, 1.0 kPa or more, 3.0 kPa or more, or 5. It may be 0 kPa or more, 10 kPa or less, 5 kPa or less, 3 kPa or less, or 1 kPa or less.

The loss tangent tan δ of the photosoftened material may be 1.0 or more, 1.2 or more, 1.5 or more, 1.8 or more, or 2.0 or more, and 45 or less, 35 or less, 25 or less, 15 or less. , 5 or less, or 1.5 or less. The loss tangent tan δ is expressed as the ratio of the loss modulus G'' to the storage modulus G' (G''/G').

The storage modulus G', loss modulus G'', and tan δ of the photosoftened product can be measured by the method described in the Examples below.

The resin composition can be formed into various shapes. For example, a cured product formed into a film can be used as a film. A cured product formed into a block can be used as a block. The method of forming a membranous (film-like) or block-like cured product is not particularly limited, and any known method can be applied.

The resin materials and resin compositions can be used, for example, as adhesives, adhesives, coating materials, protective materials, and pick-up materials for parts and materials. The adhesive can be used, for example, as an adhesive that can be peeled off without destroying the adherend after temporarily fixing the adherend to the base material. Adhesives containing resin materials or resin compositions have excellent heat resistance, and therefore exhibit adhesive strength even at high temperatures of 100°C. Therefore, an adhesive containing a resin material or a resin composition can also be used as an adhesive that can withstand a high temperature process and then be peeled off by irradiation with light at room temperature.

The adhesive composition according to this embodiment contains compound A having a (meth)acryloyl group, compound B having two or more thiol groups, and a photoradical generator having a 5% weight loss temperature of 200°C or higher. In this adhesive composition, compound A includes compound A-1 having three or more (meth)acryloyl groups, and at least one of compound A and compound B has a disulfide bond in the molecule. In this adhesive composition, the specific aspects of compound A, compound B, the photoradical generator, and other components can be those described above.

The adhesive composition can form a cured product of the adhesive composition through the reaction of Compound A and Compound B, and can act as an adhesive layer for bonding two or more adherends. The reaction conditions for Compound A and Compound B may be as described above.

The cured product of the adhesive composition has photosoftening properties. Therefore, the cured product of the adhesive composition can be separated from two or more adherends without destroying them by light irradiation. The softened material remaining on the adherend can be removed with a solvent if necessary. The conditions for light irradiation may be the conditions described above.

The adherend may be, for example, a fine structure, a fragile adherend, or an adherend that is vulnerable to physical stress. Examples of the fine structures include microchannels, fine wiring, and microbumps. Examples of easily breakable adherends include ultra-thin wafers and glass. Examples of adherends that are vulnerable to physical stress include soft tissues and cells.

The adhesive body of one embodiment includes a first adherend, a second adherend, and an adhesive layer that adheres the first adherend and the second adherend to each other. The adhesive layer contains a cured adhesive composition. The adhesive body can be manufactured by a method including a step of bonding a first adherend and a second adherend together via an adhesive composition. The curing conditions may be the reaction conditions described above. Even after enduring a high temperature process, the bonded body can be separated by light irradiation.

A method for separating adherends according to one embodiment includes a step of irradiating the adhesive layer of the adhesive body with light to separate the first adherend and the second adherend. Since the adhesive layer contains the cured product of the photocurable composition described above, by irradiating it with light, the cured product of the photocurable composition is melted and the adherends can be easily separated from each other. can do. The adherends can be separated by light irradiation even after enduring high temperature processes.

In the method for separating adherends, the type of light, light source, etc. when irradiating light may be the same as above.

Hereinafter, the present disclosure will be specifically explained with reference to Examples, but the present disclosure is not limited to these Examples.

1-1. Test Materials The materials used in the synthesis were the purchased materials as they were.
Thiokol LP-55 (manufactured by Toray Fine Chemical Co., Ltd., SH%=1.8%) was used as a compound having two or more thiol groups. Polyethylene glycol diacrylate (Fancryl FA-220; manufactured by Showa Denko Materials Co., Ltd.) was used as a compound having two (meth)acryloyl groups. As a compound having three or more (meth)acryloyl groups, trimethylolpropane triacrylate (Fancryl FA-133; manufactured by Showa Denko Materials Co., Ltd.) was used. 2,4,6-trisdimethylaminomethylphenol (ADEKA Hardener EHC-30; manufactured by ADEKA Corporation) was used as a curing catalyst. As a photoradical generator, 2-(dimethylamino)-2-(4-methylbenzyl)-1-[4-morpholin-4-yl-phenyl)butan-1-one (Omnirad-379EG; IGM Resins B.V. (manufactured by Co., Ltd., 5% weight loss temperature: 248°C) was used.

1-2. Preparation of resin composition and film for evaluation The materials were mixed in a 100 mL plastic ointment pot, heated at 95°C for 1 hour, and then stirred at a rotation speed of 2000 rpm using a rotational revolution stirrer (Awatori Rentaro ARE-310; manufactured by Shinky Co., Ltd.). The mixture was stirred for 3 minutes to complete the blending. The resulting composition along with a spacer of the desired film thickness was sandwiched between the release surfaces of two pieces of release PET (Film Biner DB-50 (manufactured by Fujimori Industries Co., Ltd.)), and after curing at room temperature for one week, the composition was released. The film obtained by peeling off the mold film was used as a specimen for various evaluations. The completion of the reaction was confirmed from the infrared absorption spectrum measurement results, and the reaction was considered complete when the integral value of the peak derived from the double bond of the acrylic group near 810 cm ^-1 decreased by 95% or more compared to the unpolymerized state. .

1-3. Light Irradiation For UV irradiation, a UV irradiation device (manufactured by Panasonic Devices SUNX Co., Ltd., power supply: Aicure UJ30, 365 nm LED head: ANUJ6186, 405 nm LED head: ANUJ6189) was used. The irradiation conditions were measured using a luminometer UIT-250 (manufactured by Ushio Inc.) using receivers for 365 nm and 405 nm, respectively.

1-4. Mechanical property evaluation A glass stage for microscopic observation and an 8mm disposable rotor were used as options for the viscoelasticity measuring device (manufactured by TA Instruments, product name: DHR-2), as described in "1-3. Light irradiation" from the bottom of the glass stage. By irradiating the evaluation sample with light using a UV irradiation device, changes in viscoelasticity in response to light irradiation were evaluated. Measurements were performed with a gap between the stage and rotor of 500±200 μm, a frequency of 1 Hz, and a displacement of 1%. For the measurement, a 500±200 μm thick film obtained by the method of “1-2. Preparation of resin composition and evaluation film” was punched out into a cylindrical shape with a diameter of 8 mm. The temperature dependence of viscoelasticity was measured by replacing the glass stage for microscope observation with a Peltier plate.

1-5. Adhesive force evaluation As shown in Figure 1, the resin composition obtained by the method of "1-2. Preparation of resin composition and evaluation film" has an adhesive area of a circle with a diameter of 10 to 13 mm, and an adhesive layer thickness of 100±. A shear test piece was obtained by sandwiching it between two glass slides (S-1112; manufactured by Matsunami Glass Industries Co., Ltd.) or two polycarbonate plates so that the thickness was 20 μm, and allowing it to stand at room temperature for one week.

Completion of curing was confirmed by infrared absorption spectroscopy, and curing was determined to be complete when the integral value of the peak of the acrylic group near 810 cm ⁻¹ decreased by 95% or more compared to the unreacted state.

The shear adhesive strength of the obtained shear test piece was measured using Autograph AGS-X manufactured by Shimadzu Corporation in an environment of 25° C. and 100° C. at a tensile rate of 10 mm/min.

1-6. GPC measurement Molecular weight was measured by gel permeation chromatography (GPC) using Chromaster manufactured by Hi-Tech Science Co., Ltd., with a column of GL-A130-S, GL-A150-S, GL-A160-S and a detector of RI. The measurement was carried out at a temperature of 35°C. A THF (tetrahydrofuran) solution with a sample concentration of 1 wt% was prepared and used as a sample for GPC. Molecular weight conversion values were calculated using a calibration curve using standard polystyrene molecules. A film with a film thickness of 500 ± 100 μm obtained by the method of “1-2. Preparation of resin composition and evaluation film” was sandwiched between two glass slides (S-1111; manufactured by Matsunami Glass Industries Co., Ltd.), and the wavelength A viscous liquid photomelted by irradiation with 365 nm or 405 nm LED light at an illuminance of 1000 mW/cm ² for 120 seconds was used as a sample.

1-7. Thermogravimetric/differential thermal analysis (TG-DTA)
For thermogravimetric/differential thermal analysis, EXSTAR TG/DTA 7200 manufactured by SII Nano Technology Co., Ltd. was used. Approximately 10 mg of the film sample obtained by the method of "1-2. Preparation of resin composition and evaluation film" was collected in a sample pan, and heated from room temperature to approximately 300°C for 10 minutes while flowing nitrogen gas at a flow rate of 300 ML/min. The temperature was raised at a rate of °C/min, and a 5% weight loss temperature was confirmed.

2-1. Characteristics of Resin Composition A linear resin composition was synthesized by Michael addition of polysulfide, which is a terminal difunctional thiol (molecular weight approximately 3700) having a disulfide bond in the chain, and polyethylene glycol diacrylate. This was used as the resin composition of Comparative Example 1. A crosslinking site was provided by substituting a part of the diacrylate in the composition of the resin composition of Comparative Example 1 with polyethylene glycol triacrylate. The resin compositions thus obtained were designated as Examples 1 to 4. The raw materials, thiol group (mercapto group) and acrylic group, were blended in a molar ratio of 1:1.

We investigated how (1) the distance between crosslinking points (amount of crosslinking and crosslinking density) and (2) the amount of Omnirad-379EG in the resin composition affect changes in mechanical properties due to photodecomposition. investigated.

First, the distance between crosslinking points (the amount of crosslinking and the crosslinking density) of the resin composition was investigated. According to the blending amounts in Tables 2 and 3, the blending amount of Omnirad-379 was fixed, and the distance between crosslinking points (crosslinking amount and crosslinking density) was adjusted by adjusting the blending amounts of diacrylate and triacrylate. Table 2 shows the material molar ratio, distance between crosslinking points, and finger touch test results for each formulation. Table 3 shows the weight ratio of each formulation.

The curing method was carried out with reference to previous reports on the reaction between thiol groups and acrylic groups. By blending 2 parts by weight of 2,4,6-trisdimethylaminomethylphenol (ADEKA Hardener EHC-30; manufactured by ADEKA Co., Ltd.) as a catalyst, the Michael addition reaction between the thiol group and the acrylic group was allowed to proceed at room temperature. . The curing rate was calculated from the measurement results of the infrared absorption spectrum. Polymerization was considered complete when the integral value of the peak of the acrylic group near 810 cm ⁻¹ in the measurement results of the infrared absorption spectrum decreased by 95% or more compared to the unpolymerized state. Since a trifunctional monomer was used as a crosslinking site, the distance between crosslinking points Mc was calculated by considering one molecule of triacrylate itself as a crosslinking point and excluding the influence of plasticity such as a photoradical generator. Table 4 shows the results of evaluating the mechanical properties and photosoftening properties of the obtained resin composition.

The obtained resin composition exhibited low elasticity of 1 MPa or less because polysulfide containing polyether chains was used as a raw material.

As shown in Tables 2 to 4, as the molar ratio and weight ratio of triacrylate (shortening the distance between crosslinking points and increasing crosslinking density) increases, an increase in storage modulus and a decrease in tan δ and tack are observed. Ta.

When films made of the resin compositions of Examples 1 to 4 and Comparative Example 1 were laminated, the presence or absence of adhesion between the films, so-called tackiness, was checked. As a result, tack disappeared in a film made of a resin composition in which the molar ratio of triacrylate to polysulfide was 33.3% or more and the distance between crosslinking points was about 8000 g/mol or less.

Since the resin composition of the example has a crosslinked structure, it is expected to have an effect of improving heat-resistant creep property. Furthermore, since the resin compositions of Examples have a crosslinked structure, they are expected to have the effect of improving chemical resistance and heat aging resistance. Therefore, the resin composition of the example can be suitably used as an engineering plastic, for example. The 5% weight loss temperature of the resin composition did not vary greatly depending on the distance between crosslinking points, suggesting that the radical generator and the structure of the resin were the controlling factors.

Next, the photosoftening properties of the resin compositions of Examples 1 to 4 and Comparative Example 1 were evaluated. The resin compositions of Examples 1 to 4 and Comparative Example 1 were irradiated with LED light with a wavelength of 405 nm for 2 seconds at 500 mW/cm ² every 10 seconds, and the viscoelasticity was measured. The results are shown in FIGS. 2 and 3. FIG. 2 shows the results of evaluating the photoresponsiveness of G' of the resin composition, and shows the results of repeated irradiation with LED light with a wavelength of 405 nm for 2 seconds at 500 mW/cm ² every 10 seconds starting 10 seconds after the start of the measurement. FIG. 3 shows the tan δ photoresponsive evaluation results of the resin composition, and shows the results of repeated irradiation with LED light with a wavelength of 405 nm for 2 seconds at 500 mW/cm ² every 10 seconds from 10 seconds after the start of measurement. The resin compositions of Examples exhibited photosoftening properties. FIG. 4 is a photograph showing the appearance of the resin composition after light irradiation, in which (A) shows the results of Example 1, (B) shows the results of Example 2, and (C) shows the results of Example 3. Regarding the resin composition of Example 1 in which the molar ratio of triacrylate to polysulfide was 66.7%, the tan δ after irradiation with 30 J/cm ² light was around 1, and the resin composition became gel-like. The resin compositions of Examples 3 and 4, in which the molar ratio of triacrylate to polysulfide was 13.3% or less, were particularly excellent in photosoftening properties. In the resin compositions of Examples 3 and 4, when the irradiation dose was 2,000 mJ/cm ² or more, the tan δ exceeded 2.0, indicating a liquid state, and the storage modulus was 10,000 Pa or less.

When the resin composition after photosoftening was subjected to GPC measurement, a negative correlation was confirmed between the number average molecular weight of the resin composition after photosoftening and the amount of the photoradical generator compounded. On the other hand, a positive correlation was confirmed between the weight average molecular weight of the photosoftened resin composition and the viscosity of the photosoftened resin composition, and the amount of triacrylate (crosslinking amount).

It is estimated that among the radicals generated from Omnirad-379EG, benzoyl radicals contribute to the cleavage of disulfide bonds, so it is thought that 2 moles of Omnirad-379EG cleaves 1 mole of disulfide bonds. In other words, the number of moles of molecular chain terminals newly generated in the resin composition due to photosoftening is equivalent to the number of moles of the photoradical generator. Since the number of molecular chain terminals is inversely proportional to the number average molecular weight, it is considered that a negative correlation was confirmed between the number average molecular weight of the resin composition after photosoftening and the amount of the photoradical generator compounded.

If the phenomenon of softening of a resin composition is regarded as destruction of the network structure, it is thought that a photo-softening resin composition liquefies only after all crosslinks are severed. In other words, in order to liquefy by photosoftening, it is expected that at least the number of bonds to be broken must exceed the number of crosslinking points. When the molar ratio of the photoradical generator and the triacrylate is 2:1, the cutting point equals the crosslinking point, so it is considered that the formulation is on the borderline of whether or not it liquefies due to photosoftening. The molar ratio in Example 1 is 66.7 moles of triacrylate to 120 moles of photoradical generator, and the number of bonds broken is estimated to be 60.0 moles with respect to 66.7 moles of crosslinking points. Although No. 1 exhibits photosoftening properties, it is expected to have a composition that is difficult to liquefy. In fact, although the resin composition of Example 1 after being irradiated with light showed photosoftening properties, it remained in a gel-like state and was not liquefied. In the resin compositions other than Example 1, since bonds exceeding the number of crosslinking points were sufficiently severed, liquefaction due to photosoftening was observed. It has been suggested that the degree of photosoftening can be adjusted by, for example, the amount of crosslinking in the resin composition and the amount of photoradical generator blended.

An assumed reaction formula for photosoftening of the resin composition is shown in Scheme 3. Scheme 3 shows a reaction in which a benzoyl radical contributes to the cleavage of a disulfide bond, and a reaction in which a thiyl radical undergoes an exchange reaction with a disulfide in the molecule, resulting in cyclization.
Scheme 3:

2-2. Characteristics as an adhesive due to photosoftening Among the resin compositions obtained in “2-1. Characteristics of resin composition”, the resin composition of Example 3 in which the molar ratio of triacrylate to polysulfide was 13.3% The properties of the adhesive as an adhesive were evaluated. The adhesive force measurement results are shown in Table 5 and FIG.

The shear adhesive strength of the resin composition of Example 3 before light irradiation was 86 N/cm ² at 25°C on a polycarbonate base material, and the resin composition exhibited adhesive strength comparable to general OCR (Optical Clear Resin) at 25°C. was confirmed. The shear adhesive strength of the resin composition of Example 3 before light irradiation was 26 N/cm ² even in a high temperature environment of 100°C. As described above, the resin composition of Example 3 exhibited adhesive strength without being softened by heating. The shear adhesive strength of the resin composition of Example 3 after photosoftening was measured according to the following procedure. First, a resin portion of a shear test piece prepared using the resin composition of Example 3 was irradiated with an LED lamp (illuminance: 1000 mW/cm ² ) having a wavelength of 405 nm for 5 seconds. The obtained resin composition of Example 3 after being irradiated with light shifted due to a slight force when it was installed and fixed in an autograph for measuring adhesive strength. There was no peak in the measured value of the shear adhesive force of the resin composition of Example 3 after irradiation with light, and the value was below noise and could not be measured. That is, it can be said that in the resin composition of Example 3 after light irradiation, the shear adhesive force and the stress applied to the base material were extremely close to zero.

FIG. 6 shows the results of storage modulus, loss modulus, and tan δ at high temperatures of Example 3 and Comparative Example 1, with (A) showing the results of Example 3 and (B) showing the results of Comparative Example 1. Before light irradiation, no decrease in storage modulus was observed in the resin composition of Example 3 even on the high temperature side. In the resin composition of Comparative Example 1, the storage modulus decreased on the high temperature side, and softening due to heat was confirmed.

Figure 7 shows the appearance of a shear test piece prepared using the resin composition of Example 3 after measuring adhesive strength, (a) shows the appearance of the shear test piece before measurement, and (b) shows the appearance of the shear test piece before measurement. FIG. 3(c) shows the peeled state of an unirradiated sample, FIG. 3(c) shows the peeled state after light irradiation, and FIG. 3(d) shows the appearance of the shear test piece shown in FIG. The sample before photosoftening, which had a polycarbonate plate with high adhesive strength as the adherend, had cohesive failure of the cured material remaining on both sides of the adherend, and the sample after photosoftening had liquid remaining on both sides of the adherend. was. The liquid after photosoftening has high cleaning properties, and by washing with acetone flowing for several seconds, it was confirmed that residues were removed from the glass surface.

From the above results, the resin materials and resin compositions of Examples can be applied to fine structures such as microchannels, fine wiring, microbumps, etc., fragile ultra-thin wafers, glass, extremely soft tissues, cells, etc. It is expected that this adhesive will be used as an easily removable adhesive that can be used to temporarily attach adherends that are vulnerable to physical stress to some kind of base material and then peel them off without damaging the adherend. The resin composition of the example exhibits sufficient adhesive strength even at a high temperature of 100°C, so it can be used, for example, as a high-performance temporary adhesive that can withstand a high-temperature process and then be peeled off by light irradiation at room temperature. It is expected that it will be applied as a.

Claims

A compound A having a (meth)acryloyl group,
Compound B having two or more thiol groups,
A photoradical generator having a 5% weight loss temperature of 200°C or higher,
The compound A includes a compound A-1 having three or more (meth)acryloyl groups,
A resin material in which at least one of the compound A and the compound B has a disulfide bond in the molecule.
The resin material according to claim 1, wherein the compound A further contains a compound A-2 having two (meth)acryloyl groups.
The radical generator is a compound that gives benzoyl radicals when irradiated with light,
The resin material according to claim 1 or 2, wherein the ratio of the number of moles of the benzoyl radical to the number of moles of the compound A-1 is 21/20 or more.
A reaction product of a compound A having a (meth)acryloyl group and a compound B having two or more thiol groups,
A photoradical generator having a 5% weight loss temperature of 200°C or higher,
The compound A includes a compound A-1 having three or more (meth)acryloyl groups,
A resin composition in which at least one of the compound A and the compound B has a disulfide bond in the molecule.
The resin composition according to claim 4, wherein the compound A further contains a compound A-2 having two (meth)acryloyl groups.
the radical generator is a compound that gives a benzoyl radical upon irradiation with light,
The resin composition according to claim 4, wherein the ratio of the number of moles of the benzoyl radical to the number of moles of the compound A-1 is 21/20 or more.