JP2015199793A - Pressure-sensitive adhesive and method for using the same, and pressure-sensitive adhesive material and method for using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure-sensitive adhesive having excellent heat resistance and releasability even when exposed to a high temperature environment.SOLUTION: The pressure-sensitive adhesive comprises a condensation resin having a polyoxyalkanediyl group or a 1,4-piperazinediyl group, and a compound containing boron. The condensation resin comprises a structural unit obtained by condensation-polymerizing a polymerizable monomer comprising: at least one monomer (A) selected from a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an ester of the carboxylic acid, and a halide of the carboxylic acid; and a monomer (B) having at least two amino groups. The monomer (B) comprises a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups, and a monomer (b2) having a 1,4-piperazinediyl group and at least two amino groups.

Description

  The present invention relates to a pressure-sensitive adhesive, a method for using the same, a pressure-sensitive adhesive material including a pressure-sensitive adhesive layer containing the pressure-sensitive adhesive, and a method for using the pressure-sensitive adhesive. The present invention relates to a method, a pressure-sensitive adhesive material including a pressure-sensitive adhesive layer containing the pressure-sensitive adhesive, and a method of using the same.

  In the semiconductor industry, there is a demand for thinner semiconductor wafers in order to cope with thinner semiconductor packages and higher chip densities. In the display industry, in order to cope with thinner and flexible displays, There is a demand for thinning a base material for forming a thin film transistor (TFT).

  However, as wafers and substrates are made thinner, handling during the manufacturing process is extremely reduced, and wafers and substrates are distorted and dimensional fluctuations occur. Is difficult. Therefore, manufacturers have proposed a method in which a thin wafer or substrate is temporarily fixed to a highly rigid support using a heat-resistant heat-resistant adhesive, and the product is peeled off from the support after the manufacturing process is completed.

  Conventionally, acrylic heat-resistant adhesives are often used as heat-resistant adhesives. Moreover, as a heat resistant adhesive, a silicone-based heat resistant adhesive is known (for example, refer to Patent Document 1 below). Furthermore, as a heat-resistant adhesive, a material that is pasted at a high temperature using a thermoplastic resin is known (for example, see Patent Document 2 below).

  As the peeling of the adhesive, mechanical peeling by lift-up or the like, dissolution peeling by a solvent, melt peeling by heating, thermal foaming peeling, or UV foaming peeling are used (for example, see Patent Documents 3 to 7 below).

JP 2009-256542 A Japanese Patent Laid-Open No. 09-74266 JP 2009-135099 A Japanese Patent No. 2965476 Japanese Patent No. 4639575 JP 2007-254580 A JP 2009-272478 A

  By the way, the acrylic heat-resistant pressure-sensitive adhesive has a problem in that the adhesiveness cannot be maintained in a high-temperature environment (for example, 200 ° C. or more), and floating or peeling occurs. In addition, the silicone-based heat-resistant adhesive has a problem that it is expensive and the object to be attached is limited (for example, the adhesiveness to a plastic material such as a polyester film or a polyimide film is low).

  When a thermoplastic resin is used to improve such heat resistance (for example, 200 ° C. or higher), a pasting temperature higher than the use temperature is required, and furthermore, a peeling temperature higher than the use temperature is required for melt peeling. There was a problem in workability. In addition, solvent cleaning may be required to remove the adhesive residue, and there is a problem in productivity.

  Furthermore, regarding mechanical peeling, if the adhesive strength is too low, it causes peeling during the process, and if the adhesive strength is too high, the adherend or the process formed on the adherend due to the peeling stress This may cause damage to objects, and is not preferable as a method for peeling an adherend having a particularly large elastic modulus.

  With regard to dissolution peeling that has improved this problem, dissolution or penetration by a solvent may cause damage to the adherend or a workpiece formed on the adherend, and the process time depends on the dissolution time. There was a problem that it was long and inferior in productivity. On the other hand, thermal foaming peeling and UV foaming peeling have restrictions on the foaming temperature and foaming efficiency of the foaming agent, and there are restrictions on application at the use temperature of the adhesive (for example, 200 ° C. or more).

  Therefore, the present invention provides a pressure-sensitive adhesive having excellent heat resistance and peelability even when exposed to a high temperature environment, a method for using the same, a pressure-sensitive adhesive provided with a pressure-sensitive adhesive layer containing the pressure-sensitive adhesive, and the use thereof It aims to provide a method.

  The pressure-sensitive adhesive according to the present invention includes a condensation resin and a compound containing boron.

  According to such a pressure-sensitive adhesive, even when the pressure-sensitive adhesive is exposed to a high temperature environment (for example, 200 ° C. or higher), excellent heat resistance is obtained, and excellent pressure-sensitive adhesiveness is maintained. Is sufficiently suppressed. Moreover, according to the said adhesive, even if it is a case where an adhesive is exposed to high temperature environment (for example, 200 degreeC or more), the outstanding peelability is obtained, and after adhere | attaching an adherend on an adhesive, an adherend Can be peeled from the adhesive.

  The condensation resin preferably has a polyoxyalkanediyl group. The condensation resin preferably has a 1,4-piperazinediyl group.

  The condensation resin includes at least one monomer (A) selected from the group consisting of a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halide of the carboxylic acid. It is preferable to have a structural unit obtained by condensation polymerization of a polymerizable monomer containing a monomer (B) having at least two amino groups.

  The monomer (B) includes a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups, and a monomer (b2) having a 1,4-piperazinediyl group and at least two amino groups. Is preferred.

  The content of the monomer (b1) in the polymerizable monomer is preferably 0.5 to 20 mol% based on the total amount of the monomer (A) and the monomer (B).

  The monomer (B) preferably includes a monomer having a cyclohexyl group and at least two amino groups.

  The monomer (A) preferably has a divalent aromatic ring group.

  The condensation resin includes at least one monomer (A) selected from the group consisting of a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halide of the carboxylic acid. It is preferable to have the derived structural unit (A) and the structural unit (B) derived from the monomer (B) having at least two amino groups.

  The structural unit (B) has a structural unit (b1) derived from a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups, a 1,4-piperazinediyl group, and at least two amino groups. And a structural unit (b2) derived from the monomer (b2).

  The content of the structural unit (b1) is preferably 0.5 to 20 mol% based on the total amount of the structural unit (A) and the structural unit (B).

  The structural unit (B) preferably includes a structural unit having a cyclohexyl group.

  The structural unit (A) preferably has a divalent aromatic ring group.

  It is preferable that at least one selected from the group consisting of the carboxylic acid and its anhydride and the monomer (B) in the monomer (A) is liquid at 25 ° C.

  The condensed resin preferably has a divalent aromatic ring group.

  The pressure-sensitive adhesive according to the present invention may be used as a heat-resistant pressure-sensitive adhesive that is affixed to an adherend and is peeled off from the adherend after being heated to 200 ° C. or higher.

  The content of the condensation resin is preferably 50% by mass or more based on the total solid content of the pressure-sensitive adhesive.

  The pressure-sensitive adhesive material according to the present invention includes a support and a pressure-sensitive adhesive layer provided on the support, and the pressure-sensitive adhesive layer contains the pressure-sensitive adhesive.

  The method of using the pressure-sensitive adhesive according to the present invention includes a sticking step of sticking the first adherend to the second adherend through the pressure-sensitive adhesive layer containing the pressure-sensitive adhesive, and the temperature of the pressure-sensitive adhesive layer is 200 ° C. A heating process for heating the first adherend and the second adherend under the above-described conditions, and the adhesive layer and the second adherend from the first adherend subjected to the heating process. And a peeling step for peeling off the body.

  In the method of using the pressure-sensitive adhesive according to the present invention, at least one of the first adherend and the second adherend may be a silicon wafer.

  The method of using the pressure-sensitive adhesive material according to the present invention includes a sticking step of sticking the pressure-sensitive adhesive layer of the pressure-sensitive adhesive material to an adherend, and heating the adherend under conditions where the temperature of the pressure-sensitive adhesive layer is 200 ° C. or higher. A heating step, and a peeling step for peeling the adhesive material from the adherend that has undergone the heating step.

  In the method for using the adhesive material according to the present invention, the adherend may be a silicon wafer.

  According to the present invention, excellent heat resistance and peelability can be obtained even when the pressure-sensitive adhesive is exposed to a high temperature environment (for example, 200 ° C. or more).

  The pressure-sensitive adhesive according to the present embodiment, a method for using the pressure-sensitive adhesive, a pressure-sensitive adhesive material including a pressure-sensitive adhesive layer containing the pressure-sensitive adhesive, and a method for using the pressure-sensitive adhesive are described below.

<Adhesive>
The pressure-sensitive adhesive according to this embodiment includes a condensation resin (I) and a compound (II) containing boron. The pressure-sensitive adhesive according to the present embodiment can be used as a heat-resistant pressure-sensitive adhesive that is affixed to an adherend and peeled off from the adherend after being heated to a high temperature (for example, 200 ° C. or higher).

((I) component: condensation resin)
The condensation resin is, for example, a resin having adhesiveness. Examples of the condensation resin include polyamide resin, polyimide resin, and polyamideimide resin. Among these, a polyamide resin is preferable from the viewpoint of excellent heat resistance.

  The condensation resin may be obtained by further modifying a polymer obtained by condensation polymerization, such as olefin-modified polyamide, alkoxysilane-modified polyamide, siloxane-modified polyimide, epoxy-modified polyamide, polycarbonate-modified polyamide, olefin-modified polyimide, siloxane. Examples include modified polyimide, epoxy-modified polyimide, polycarbonate-modified polyimide, siloxane-modified polyimide, olefin-modified polyamideimide, alkoxysilane-modified polyamideimide, siloxane-modified polyamideimide, epoxy-modified polyamideimide, epoxy-modified polyamideimide, and polycarbonate-modified polyamideimide.

  The condensed resin is, for example, at least one monomer (A) selected from the group consisting of a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halide of the carboxylic acid. And a structural unit obtained by condensation polymerization of a polymerizable monomer containing a monomer (B) having at least two amino groups. That is, the condensed resin is, for example, at least one monomer selected from the group consisting of a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halide of the carboxylic acid ( A structural unit (A) derived from A) and a structural unit (B) derived from a monomer (B) having at least two amino groups.

  The structural unit (A) derived from the monomer (A) in the condensation resin can be referred to as a monomer (A) unit, and the structural unit (B) derived from the monomer (B) is referred to as a monomer (B) unit. The condensation resin can be referred to as a condensation resin including a monomer (A) unit and a monomer (B) unit.

  The monomer (A) and monomer (B) that can form the structural unit can be confirmed, for example, by the following method. That is, a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halide of the carboxylic acid, which are generated when the structural unit is hydrolyzed, are monomer (A). It can be. Moreover, the monomer (B) can be a compound having at least two amino groups, which is produced when the structural unit is hydrolyzed.

For example, the structural unit represented by the following formula (1-1) includes a carboxylic acid represented by the following formula (A-1), an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halogen of the carboxylic acid. It can be said that it is a structural unit obtained by condensation polymerization of at least one monomer selected from the group consisting of compounds and a monomer represented by the following formula (B-1). In the formula, R ¹ and R ² represent a divalent organic group.

In addition, for example, the structural unit represented by the following formula (1-2) includes a carboxylic acid represented by the following formula (A-2) and an anhydride of the carboxylic acid represented by the following formula (A-2 ′). A structural unit obtained by condensation polymerization of at least one monomer selected from the group consisting of a product, an esterified product of the carboxylic acid and a halide of the carboxylic acid, and a monomer represented by the formula (B-1) be able to. In the formula, R ³ represents a trivalent organic group.

Furthermore, for example, the structural unit represented by the following formula (1-3) includes a carboxylic acid represented by the following formula (A-3) and an anhydride of the carboxylic acid represented by the following formula (A-3 ′). A structural unit obtained by condensation polymerization of at least one monomer selected from the group consisting of a product, an esterified product of the carboxylic acid and a halide of the carboxylic acid, and a monomer represented by the formula (B-1) be able to. In the formula, R ⁴ represents a tetravalent organic group.

  As the carboxylic acid of the monomer (A), a carboxylic acid having two carboxyl groups (monomer represented by the formula (A-1)), a carboxylic acid having three carboxyl groups (the formula (A-2)) Monomer), a carboxylic acid having four carboxyl groups (monomer represented by the formula (A-3)), and the like.

  Examples of the carboxylic acid having two carboxyl groups include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, dodecanedioic acid, Alkylene dicarboxylic acids such as tetradecanedioic acid, pentadecanedioic acid, octadecanedioic acid; phthalic acid, terephthalic acid, isophthalic acid, 5-hydroxyisophthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2, Arylenedicarboxylic acids such as 6-naphthalenedicarboxylic acid; 4-methylhexahydrophthalic acid, 3-methylhexahydrophthalic acid, 2-methylhexahydrophthalic acid, 3-ethylhexahydrophthalic acid, 2-ethylhexahydrophthalic acid , Methyl norbornane-2,3-dicarboxylic acid, methyl Such dicarboxylic acids having a cyclohexane skeleton such as norbornane-3,4-dicarboxylic acid.

  Examples of the carboxylic acid having three carboxyl groups include aromatic tricarboxylic acids such as trimellitic acid; and alicyclic tricarboxylic acids such as cyclohexane-1,2,4-tricarboxylic acid.

  Examples of carboxylic acids having four carboxyl groups include pyromellitic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,4,5-naphthalene. Tetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid, 3,3 ′, 4,4′-biphenyl ether tetracarboxylic acid, 3, 3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,5,6-pyridinetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, 4,4'-sulfonyldiphthalic acid, 1 -Trifluoromethyl-2,3,5,6-benzenetetracarboxylic acid, 2,2 ', 3,3'-biphenyltetracarboxylic acid, 2,2-bis (3,4-dicarboxypheny ) Propane, 2,2-bis (2,3-dicarboxyphenyl) propane, 1,1-bis (2,3-dicarboxyphenyl) ethane, 1,1-bis (3,4-dicarboxyphenyl) ethane Bis (2,3-dicarboxyphenyl) methane, bis (3,4-dicarboxyphenyl) methane, bis (3,4-dicarboxyphenyl) sulfone, bis (3,4-dicarboxyphenyl) ether, benzene -1,2,3,4-tetracarboxylic acid, 2,3,2 ′, 3′-benzophenone tetracarboxylic acid, 2,3,3 ′, 4′-benzophenone tetracarboxylic acid, phenanthrene-1,8,9 , 10-tetracarboxylic acid, pyrazine-2,3,5,6-tetracarboxylic acid, thiophene-2,3,4,5-tetracarboxylic acid, 2,3,3 ′, 4′-bifu Nyltetracarboxylic acid, 3,4,3 ′, 4′-biphenyltetracarboxylic acid, 2,3,2 ′, 3′-biphenyltetracarboxylic acid, bis (3,4-dicarboxyphenyl) dimethylsilane, bis ( 3,4-dicarboxyphenyl) methylphenylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 1,4-bis (3,4-dicarboxyphenyldimethylsilyl) benzene, 1,3-bis (3 , 4-Dicarboxyphenyl) -1,1,3,3-tetramethyldicyclohexane, p-phenylenebis (trimellitate), ethylenetetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, decahydronaphthalene -1,4,5,8-tetracarboxylic acid, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene -1,2,5,6-tetracarboxylic acid, cyclopentane-1,2,3,4-tetracarboxylic acid, pyrrolidine-2,3,4,5-tetracarboxylic acid, 1,2,3,4- Cyclobutanetetracarboxylic acid, bicyclo- (2,2,2) -oct (7) -ene 2,3,5,6-tetracarboxylic acid, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane 2,2-bis (4- (3,4-dicarboxyphenoxy) phenyl) hexafluoropropane, 4,4′-bis (3,4-dicarboxyphenoxy) diphenyl sulfide, 4,4 ′-(4 4′isopropylidenediphenoxy) -bis (phthalic acid), tetrahydrofuran-2,3,4,5-tetracarboxylic acid, bis (exobicyclo (2,2,1) heptane-2,3-dicarboxylic acid) ) Sulfone, 1,2,4,5-tetracarboxycyclohexane, bicyclo [2.2.2] octane-2,3: 5,6-tetracarboxylic acid, 5,5′-endo- (polysiloxane-1, 5-diyl) -bisbicyclo [2,2,1] heptane-exo-2,3-dicarboxylic acid and the like.

  As the monomer (B), a monomer having two amino groups is preferable. Monomers having two amino groups include 2,2-bis [4- (4-aminophenoxy) phenyl] propane, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-amino). Phenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, bis [4- (4-aminophenoxy) phenyl] methane, 4,4′-bis (4-amino) Phenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ketone, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 2,2′-dimethylbiphenyl-4,4′-diamine, 2,2′-bis (trifluoromethyl) ) Biphenyl-4,4′-diamine, 2,6,2 ′, 6′-tetramethyl-4,4′-diamine, 5,5′-dimethyl-2,2′-sulfonyl-biphenyl-4,4 ′ -Diamine, (4,4'-diamino) diphenyl ether, (4,4'-diamino) diphenylsulfone, (4,4'-diamino) benzophenone, (3,3'-diamino) benzophenone, (4,4'- Aromatic diamines such as diamino) diphenylmethane, (4,4′-diamino) diphenyl ether, (3,3′-diamino) diphenyl ether; alkylene diamines such as ethylene diamine and propylene diamine; polyalkylene oxides such as polyethylene oxide diamine and polypropylene oxide diamine Diamine; (4,4'-diamino) dicyclohexyl Aliphatic diamines such as tan, isophorone diamine, 1,4-bisaminopropylpiperazine, [3,4-bis (1-aminoheptyl) -6-hexylu-5- (1-octenyl)] cyclohexene, bisaminomethylnorbornene; Examples thereof include siloxane diamines such as polydimethylsiloxane diamine.

  It is preferable that at least one selected from the group consisting of the carboxylic acid and its anhydride and the monomer (B) in the monomer (A) is liquid at 25 ° C. In this case, excellent heat resistance and peelability can be easily obtained even when the pressure-sensitive adhesive is exposed to a high temperature environment. For example, for the structural unit represented by the formula (1-1), at least one of the monomer represented by the formula (A-1) and the monomer represented by the formula (B-1) is 25 ° C. It is preferably liquid. As for the structural unit represented by the formula (1-2), the monomer represented by the formula (A-2), the anhydride represented by the formula (A-2 ′), and the formula (B-1) It is preferable that at least one selected from the group consisting of monomers represented by the formula is liquid at 25 ° C. For the structural unit represented by the formula (1-3), the monomer represented by the formula (A-3), the anhydride represented by the formula (A-3 ′), and the formula (B-1) It is preferable that at least one selected from the group consisting of monomers represented by the formula is liquid at 25 ° C.

  Among the carboxylic acid and its anhydride in monomer (A), the liquid compounds at 25 ° C. include 4-methylhexahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, 2-methylhexahydrophthalic acid. Anhydride, 3-ethylhexahydrophthalic anhydride, 2-ethylhexahydrophthalic anhydride, 5,5′-endo- (polysiloxane-1,5-diyl) -bisbicyclo [2,2,1] heptane -Exo-2,3-dicarboxylic acid anhydride etc. are mentioned.

  Among the monomers (B), the liquid compounds at 25 ° C. include ethylenediamine, propylenediamine, isophoronediamine, 1,4-bis (3-aminopropyl) piperazine, [3,4-bis (1-aminoheptyl) -6. -Hexylu 5- (1-octenyl)] cyclohexene, bisaminomethylnorbornene, alkylene oxide diamine, alkyl diamine, polyalkylene oxide diamine, siloxane diamine and the like.

  Each of the monomer (A) and the monomer (B) providing the structural unit in the condensation resin may be used alone or in combination of two or more.

  The condensed resin preferably has a polyoxyalkanediyl group. The condensed resin having such a group has a low Tg and good adhesiveness at a low temperature.

Here, examples of the polyoxyalkanediyl group include a group represented by the following formula (2). In the formula, n represents an integer of 2 or more, and R ⁵ represents an alkanediyl group. A plurality of R ⁵ may be the same as or different from each other.

The alkanediyl group in R ⁵ may be linear or branched. The alkanediyl group for R ⁵ is preferably an alkanediyl group having 2 to 4 carbon atoms, and more preferably an alkanediyl group having 2 to 3 carbon atoms. Examples of the alkanediyl group in R ⁵ include an ethylene group, 1,2-propanediyl group, 1,3-propanediyl group, 1,4-butanediyl group and the like.

  As n in Formula (2), 2-70 are preferable and 6-33 are more preferable.

  Polyoxyalkanediyl groups include polyethylene oxide, polypropylene oxide, polybutylene oxide, polytetramethylene oxide, polyethylene oxide polypropylene oxide copolymer, polyethylene glycol polytetramethylene glycol copolymer, polypropylene glycol polytetramethylene glycol copolymer And a group derived from a polyalkylene oxide such as a polyethylene glycol polypropylene glycol polytetramethylene glycol copolymer, and more preferably a polyoxyethylene group and a polyoxy-1,2-propanediyl group.

  The method for introducing the polyoxyalkanediyl group into the condensation resin is not particularly limited. For example, a method for obtaining a condensation resin using a monomer having a polyoxyalkanediyl group, a polyamide resin, a polyimide resin, or a polyamideimide resin. And a method of introducing the polyoxyalkanediyl group by modifying a condensation resin such as the above.

  The condensed resin preferably has a polyoxyalkanediyl group in at least one of the structural unit (A) and the structural unit (B), and the polyoxyalkanediyl group in the structural unit (B). It is more preferable to have. That is, the structural unit (B) preferably has a structural unit (b1) derived from a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups. Moreover, it is preferable that at least one of the monomer (A) and the monomer (B) includes a monomer having a polyoxyalkanediyl group, and the monomer (B) includes a monomer having the polyoxyalkanediyl group. preferable. That is, the monomer (B) preferably includes a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups.

  Examples of the monomer (b1) include polyalkylene oxide diamines such as Jeffamine D-230 (HUNTSMAN, trade name), Jeffamine D-400 (HUNTSMAN, trade name), Jeffamine D-2000 (HUNTSMAN, trade name). Polypropylene oxide diamines such as Jeffamine D-4000 (HUNTSMAN, trade name); polypropylene oxides such as Jeffamine ED-600 (HUNTSMAN, trade name) and Jeffamine ED-900 (HUNTSMAN, trade name) Polymeric diamines; polyethylene oxide diamines such as Jeffamine EDR-148 (HUNTSMAN, trade name), Jeffamine EDR-176 (HUNTSMAN, trade name); T-403 (HUNTSMAN, trade name), Jeffamine T-3000 (HUNTSMAN, trade name), Jeffamine T-5000 (HUNTSMAN, trade name) and the like can be suitably used as triamine such. These may be used alone or in combination of two or more.

  The content of the monomer (b1) in the polymerizable monomer is preferably 0.5 to 20 mol%, more preferably 1 to 10 mol%, and further preferably 2 to 8 mol% based on the total amount of the monomer (A) and the monomer (B). preferable. That is, the content of the structural unit (b1) in the condensed resin is preferably 0.5 to 20 mol%, more preferably 1 to 10 mol%, based on the total amount of the structural unit (A) and the structural unit (B). ˜8 mol% is more preferable. According to such a condensation resin, a heat-resistant pressure-sensitive adhesive that is further excellent in adhesion to an adherend can be obtained.

  The content of the monomer (b1) in the polymerizable monomer is preferably 5 to 20 mol%, more preferably 7 to 15 mol%, still more preferably 8 to 10 mol% based on the total amount of the monomer (B). That is, the content of the structural unit (b1) in the condensed resin is preferably 5 to 20 mol%, more preferably 7 to 15 mol%, and still more preferably 8 to 10 mol% based on the total amount of the structural unit (B). According to such a condensation resin, a heat-resistant pressure-sensitive adhesive that is further excellent in adhesion to an adherend can be obtained.

  The condensation resin preferably has a 1,4-piperazinediyl group. According to such a condensation resin, excellent peelability can be easily obtained even when the pressure-sensitive adhesive is exposed to a high temperature environment (for example, 200 ° C. or more). The structural unit (B) preferably has a 1,4-piperazinediyl group. That is, the structural unit (B) preferably has a structural unit (b2) derived from a monomer (b2) having a 1,4-piperazinediyl group and at least two amino groups. The monomer (B) preferably contains a monomer (b2) having a 1,4-piperazinediyl group and at least two amino groups. According to such a structural unit (B), excellent peelability can be easily obtained even when the pressure-sensitive adhesive is exposed to a high temperature environment (for example, 200 ° C. or higher).

  The structural unit (B) includes a structural unit (b1) derived from a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups, and a monomer having a 1,4-piperazinediyl group and at least two amino groups. And a structural unit (b2) derived from (b2). The monomer (B) includes a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups, and a monomer (b2) having a 1,4-piperazinediyl group and at least two amino groups. preferable. In these cases, excellent heat resistance and peelability can be easily obtained even when the pressure-sensitive adhesive is exposed to a high temperature environment.

  The structural unit having a polyoxyalkanediyl group may further have a 1,4-piperazinediyl group, and the structural unit not having a polyoxyalkanediyl group has a 1,4-piperazinediyl group. You may do it. Further, the monomer having a polyoxyalkanediyl group may further have a 1,4-piperazinediyl group, and the monomer not having a polyoxyalkanediyl group has a 1,4-piperazinediyl group. May be.

  Examples of the structural unit having a 1,4-piperazinediyl group include 1,4-bis (ω-aminoalkyl) piperazine units. In the 1,4-bis (ω-aminoalkyl) piperazine unit, the ω-aminoalkyl group preferably has 1 to 10 carbon atoms, and more preferably 2 to 4 carbon atoms.

  The 1,4-bis (ω-aminoalkyl) piperazine unit is preferably a 1,4-bis (3-aminopropyl) piperazine unit. That is, as the monomer (b2), 1,4-bis (3-aminopropyl) piperazine is preferable.

  The content of the monomer (b2) in the polymerizable monomer is preferably 15 to 60 mol%, more preferably 20 to 50 mol%, still more preferably 25 to 45 mol%, based on the total amount of the monomer (A) and the monomer (B). The content of the structural unit (b2) having a 1,4-piperazinediyl group in the condensation resin is preferably 15 to 60 mol%, preferably 20 to 50 mol%, based on the total amount of the structural unit (A) and the structural unit (B). Is more preferable, and 25-45 mol% is still more preferable.

  The condensed resin preferably has an alicyclic structure. The condensed resin having such a group can suppress water absorption.

  Note that the structural unit having at least one of a polyoxyalkanediyl group and a 1,4-piperazinediyl group may further have an alicyclic structure, and the polyoxyalkanediyl group and the 1,4-piperazinediyl group A structural unit that does not have both may have an alicyclic structure. In addition, the monomer having at least one of a polyoxyalkanediyl group and a 1,4-piperazinediyl group may further have an alicyclic structure, and both the polyoxyalkanediyl group and the 1,4-piperazinediyl group The monomer which does not have may have an alicyclic structure.

  Here, examples of the alicyclic structure include a cyclohexyl group, a dicyclohexyl group, a methylene dicyclohexyl group, an isophorone group, and a cyclohexyldimethyl group.

  As the monomer (A) having an alicyclic structure, 1,4-dicarboxycyclohexane, cyclohexane-1,2,4-tricarboxylic acid anhydride, cyclohexane-1,2,4,5-tetracarboxylic acid dianhydride , Dicyclohexyl-3,3 ′, 4,4′-tetracarboxylic dianhydride and the like. Examples of (B) having an alicyclic structure include bis (4-aminocyclohexyl) methane, isophoronediamine, 1,3-bis (aminomethyl) cyclohexane and the like. These can be used alone or in combination.

  The content of the monomer having an alicyclic structure in the polymerizable monomer is preferably 0.5 to 40 mol%, more preferably 1 to 20 mol%, based on the total amount of the monomer (A) and the monomer (B), and 4 to 16 mol. % Is more preferable. The content of the structural unit having an alicyclic structure in the condensed resin is preferably 0.5 to 40 mol%, more preferably 1 to 20 mol%, based on the total amount of the structural unit (A) and the structural unit (B). 4-16 mol% is still more preferable. According to such a condensation resin, the water absorption rate is further suppressed, and a change in adhesive force under a high temperature environment can be further suppressed.

  The condensed resin preferably has a cyclohexyl group (cyclohexane ring), and more preferably has a cyclohexyl group in at least one of the structural unit (A) and the structural unit (B). More preferably, the structural unit (B) has a cyclohexyl group. That is, it is preferable that the monomer (B) includes a monomer having a cyclohexyl group and at least two amino groups. In this case, excellent heat resistance and peelability can be easily obtained even when the pressure-sensitive adhesive is exposed to a high temperature environment. In addition, the condensed resin preferably has a cyclohexyl group (cyclohexane ring), a polyoxyalkanediyl group, and a 1,4-piperazinediyl group in the structural unit (B).

  The condensed resin preferably has a methylenedicyclohexyl group, more preferably has a methylenedicyclohexyl group in at least one of the structural units (A) and (B). More preferably, the unit (B) has a methylenedicyclohexyl group. It is preferable that at least one of the monomer (A) and the monomer (B) includes a monomer having a methylenedicyclohexyl group, and it is more preferable that the monomer (B) includes a monomer having a methylenedicyclohexyl group. That is, the structural unit (B) preferably has a structural unit (b3) derived from a monomer (b3) having a methylenebiscyclohexyl group and at least two amino groups. The monomer (B) preferably contains a monomer (b3) having a methylenebiscyclohexyl group and at least two amino groups. Examples of the monomer (b3) include bis (4-aminocyclohexyl) methane and 1,3-bis (aminomethyl) cyclohexane, and bis (4-aminocyclohexyl) methane is preferable.

  The content of the monomer (b3) in the polymerizable monomer is preferably 4 to 28.5 mol%, more preferably 8 to 28.5 mol%, still more preferably 8 to 20 mol% based on the total amount of the monomer (B). The content of the structural unit (b3) in the condensed resin is preferably 4 to 28.5 mol%, more preferably 8 to 28.5 mol%, still more preferably 8 to 20 mol%, based on the total amount of the structural unit (B). . According to the condensation resin having a structural unit obtained by condensation polymerization of such a polymerizable monomer, a pressure-sensitive adhesive having a suppressed water absorption and further excellent storage stability can be obtained.

The condensed resin preferably has a divalent aromatic ring group, and more preferably has a divalent aromatic ring group in the structural unit (A). That is, the monomer (A) preferably has a divalent aromatic ring group. When the condensed resin has a divalent aromatic ring group, it becomes easy to obtain excellent heat resistance in a high temperature environment. Examples of the monomer having a divalent aromatic ring group include a carboxylic acid in which R ^{1 in the} formula (A-1) is a divalent aromatic ring group, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and the carboxylic acid. Examples include acid halides.

  The structural unit having at least one of a polyoxyalkanediyl group and a 1,4-piperazinediyl group may further have a divalent aromatic ring group, and the polyoxyalkanediyl group and 1,4-piperazinediyl group The structural unit that does not have both groups may have a divalent aromatic ring group. The monomer having at least one of a polyoxyalkanediyl group and a 1,4-piperazinediyl group may further have a divalent aromatic ring group, and a polyoxyalkanediyl group and a 1,4-piperazinediyl group The monomer which does not have both may have a divalent aromatic ring group.

  The condensed resin may have a benzenediyl group as a divalent aromatic ring group, and may have at least one selected from the group consisting of a phthalic acid unit, an isophthalic acid unit, and a terephthalic acid unit. . When the condensation resin has a benzenediyl group, it becomes easy to obtain excellent heat resistance in a high temperature environment.

  The content of the monomer having a divalent aromatic ring group in the polymerizable monomer is preferably 20 to 50 mol%, more preferably 30 to 50 mol%, and more preferably 40 to 50 mol based on the total amount of the monomer (A) and the monomer (B). % Is more preferable. The content of the structural unit having a divalent aromatic ring group in the condensed resin is preferably 20 to 50 mol%, more preferably 30 to 50 mol%, based on the total amount of the structural unit (A) and the structural unit (B). 40-50 mol% is still more preferable.

The weight average molecular weight of the condensation resin is preferably 10,000 to 80,000, and more preferably 20,000 to 50,000. In addition, a weight average molecular weight shows the weight average molecular weight of polystyrene conversion measured by GPC method. The measurement apparatus and measurement conditions are as follows, for example.
<Device>
Measuring device: “HPLC-L17000H series” manufactured by Hitachi, Ltd.
Column: Shodex “GPC KD-806M”
Detector: RI detector “I-7490” manufactured by Hitachi, Ltd.
Data processing: “D7000G” manufactured by Hitachi, Ltd.
<Measurement conditions>
Column temperature: 30 ° C
Developing solvent: NMP lithium phosphate bromide solution Flow rate: 1.0 ml / min
Polystyrene used: Standard polystyrene manufactured by Tosoh Corporation (TOSOH) Sample concentration: 1.0% by mass NMP solution in terms of resin solid content

  The condensed resin is, for example, at least one monomer (A) selected from the group consisting of a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halide of the carboxylic acid. And a polymerizable monomer containing a monomer (B) having at least two amino groups. Examples of the esterified product include bis (1-isopropoxyethyl) cyclohexanedicarboxylate, bis (1-isobutoxyethyl) cyclohexanedicarboxylate, and the like. Examples of the halide include isophthaloyl dichloride and terephthaloyl dichloride. The polymerizable monomer may contain other monomers such as a diisocyanate compound.

  Although it does not restrict | limit especially as the method of condensation polymerization, For example, the method of melt | dissolving the said polymerizable monomer in a solvent, and making it react by reaction temperature 0-200 degreeC and reaction time about 1 to 5 hours is employable.

  As a solvent used for the condensation polymerization, N-methylpyrrolidone, N-ethylpyrrolidone, N-methylsuccinimide, dimethylfuran, toluene, N, N′-dimethylacetamide, hexamethylenephosphoramide, dimethylsulfoxide, γ-butyrolactone Etc. Among these, N-methylpyrrolidone is preferable from the viewpoint of the solubility of the resin.

  In condensation polymerization, an accelerator such as a catalyst can be used for the purpose of accelerating the condensation reaction. As an addition amount of an accelerator, 0.1-50 mol equivalent is preferable with respect to 10 mol equivalent of polymerizable monomers. Accelerators include inorganic salts such as lithium chloride, calcium chloride, and rhodan calcium; tertiary amines such as triethylamine and pyridine; quaternary ammonium salts such as tetramethylammonium chloride, tetraethylammonium bromide, and tetra-n-butylammonium bromide. Is mentioned.

  The content of the condensation resin in the pressure-sensitive adhesive according to this embodiment is preferably 50% by mass or more and more preferably 60 to 99.9% by mass based on the total solid content of the pressure-sensitive adhesive. When the content of the condensation resin is within the above range, higher adhesiveness can be obtained while sufficiently maintaining high heat resistance. However, the content of the condensation resin can be appropriately out of the above range depending on the application.

((II) component: a compound containing boron)
The pressure-sensitive adhesive according to this embodiment contains a compound (II) containing boron. For example, the adhesive strength varies depending on the material of the first adherend or the second adherend in the method of using the pressure-sensitive adhesive described later, but the temperature applied in the heating step during the production process is 200 ° C. or higher (particularly , Exceeding 200 ° C.), it was difficult to peel off in the peeling step after the solid adhesion and the heating step at the time of product formation. Such a phenomenon is particularly remarkable when the adherend is a silicon wafer. On the other hand, although the detailed reason is unknown, the present inventor has intensively studied, and as a result, the pressure-sensitive adhesive contains a boron-containing compound, whereby a temperature of 200 ° C. or higher (particularly, a temperature exceeding 200 ° C.). It has been found that it can be peeled even if it is applied.

  As the component (II), boron carbide; boron nitride; boronic acids such as phenylboronic acid, methylboronic acid and 2-thiopheneboronic acid; boronic acid esters such as allylboronic acid pinacolate and diisopropylmethylborane; glass powder containing boron And the like.

  The component (II) may be insoluble particles in the pressure-sensitive adhesive or may be dissolved. When the component (II) is an insoluble particle or the like in the pressure-sensitive adhesive, the average particle diameter (D50) of the component (II) is preferably 4 μm or less, and more preferably 2 μm or less. When the particle diameter exceeds 4 μm, the surface is exposed or has a convex shape when the pressure-sensitive adhesive is formed, and the surface flatness is lowered. Thereby, when bonding with a to-be-adhered body, adhesiveness may fall, such as a space | gap being formed. The lower limit of the average particle diameter of the component (II) is, for example, 10 nm. The average particle size (D50) of the component (II) can be measured by, for example, a resin zeta potential / particle size measurement system.

  The content of the component (II) in the pressure-sensitive adhesive according to this embodiment is preferably 0.01 to 40% by mass and more preferably 0.01 to 20% by mass based on the total solid content of the pressure-sensitive adhesive. When the content of the component (II) is within the above range, excellent heat resistance and peelability can be easily obtained even when the pressure-sensitive adhesive is exposed to a high temperature environment.

(Other)
The pressure-sensitive adhesive according to this embodiment is a rosin resin, a terpene resin, a coumarone resin, a phenol resin, a styrene resin, an aliphatic petroleum resin, and an aromatic resin, as long as the object of the invention is not impaired in order to improve adhesion. You may contain tackifiers, such as petroleum resin and an aliphatic aromatic copolymer petroleum resin.

<Adhesive material and formation method thereof>
The pressure-sensitive adhesive material (heat-resistant pressure-sensitive adhesive material) according to the present embodiment includes a support and a pressure-sensitive adhesive layer provided on the support, and the pressure-sensitive adhesive layer contains the pressure-sensitive adhesive according to the present embodiment.

  For example, the heat resistant adhesive is prepared by preparing a heat resistant adhesive varnish containing an adhesive, a release agent, a solvent, and the like according to the present embodiment, and applying the heat resistant adhesive varnish on one surface of the support and drying it. It can be produced by forming a layer on the one surface of the support.

  In addition, the heat-resistant adhesive material is prepared, for example, by preparing a heat-resistant adhesive varnish containing an adhesive, a release agent, a solvent, and the like according to the present embodiment, and applying the heat-resistant adhesive varnish on both sides of the support and drying it. By forming the adhesive layer on both sides of the support, it can be produced as a double-sided heat-resistant adhesive.

  Furthermore, the heat-resistant adhesive material forms, for example, a pressure-sensitive adhesive layer by applying a heat-resistant adhesive varnish containing a pressure-sensitive adhesive according to the present embodiment, a release agent, a solvent and the like onto a film such as a release film and drying it, It can be produced by laminating and transferring the adhesive layer on a support.

  Such a casting method is preferable because a flat adhesive layer can be easily obtained.

  0.1-100 micrometers is preferable and, as for the thickness (for example, thickness after drying) of the adhesion layer, 1-50 micrometers is more preferable. The thickness of the pressure-sensitive adhesive layer can be appropriately adjusted according to the concentration of the pressure-sensitive adhesive in the heat-resistant pressure-sensitive adhesive varnish and the coating amount of the heat-resistant pressure-sensitive adhesive varnish.

  The solvent used in the heat-resistant adhesive varnish is not particularly limited, but a glycol solvent, a glycol ether solvent, a glycol ester solvent, and the like are preferable because the adhesive exhibits good solubility.

  Solvents include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, propylene glycol monomethyl ether, 3-methoxy-3-methyl. Examples include -1-butanol, ethylene glycol monomethyl ether acetate, PMA (propylene glycol monomethyl ether acetate), diethylene glycol monobutyl ether acetate, and diethylene glycol monoethyl ether acetate. In addition to the above, N-methylpyrrolidone, N-ethylpyrrolidone, N-methylsuccinimide, N, N′-dimethylacetamide and dimethylformamide can also be used. These solvents may be used alone or in combination of two or more.

  The material constituting the support is not particularly limited, but a material having heat resistance to a temperature of 200 ° C. or higher is preferably used. Polyester, polyimide, polyamide, polyethersulfone, polyphenylene sulfide, polyetherketone, polyetherether Examples thereof include at least one organic material selected from ketone, triacetyl cellulose, polyetherimide, polyethylene naphthalate, polypropylene, acrylic, polystyrene, and polycarbonate. In addition, a support including an inorganic material can be used. For example, glass having high transmittance is preferable.

  The adhesive layer may be a single layer or a plurality of layers. The multi-layered adhesive layer may have an adhesive layer containing the adhesive according to the present embodiment and an adhesive layer not containing the adhesive according to the present embodiment.

  As a method for forming such a multi-layer adhesive layer, for example, after forming the first adhesive layer by applying a varnish containing one adhesive on one surface of the adherend and drying it, the other A method of forming a second adhesive layer by applying and drying a varnish containing an adhesive on the first adhesive layer, applying a varnish containing one adhesive on one surface of an adherend The first adhesive layer obtained by applying the varnish containing the other adhesive on the other surface of the other adherend and the method of sticking each other together It is done.

<Usage of adhesive and usage of adhesive>
The method of using the pressure-sensitive adhesive according to the present embodiment is to temporarily attach the first adherend to the second adherend through the pressure-sensitive adhesive layer containing the pressure-sensitive adhesive (heat-resistant pressure-sensitive adhesive) according to the present embodiment. A fixing step (temporary fixing step) for fixing, a heating step for heating the first adherend and the second adherend under conditions where the temperature of the adhesive layer is high (eg, 200 ° C. or higher), and a heating step And a peeling step of peeling the pressure-sensitive adhesive layer and the second adherend from the first adherend that has undergone the above. At least one of the first adherend and the second adherend is, for example, a silicon wafer.

  The method of using the adhesive material according to the present embodiment includes an attaching step (temporary fixing step) in which the adhesive layer of the adhesive material according to this embodiment is attached to an adherend and temporarily fixed, and the temperature of the adhesive layer is high (for example, A heating step of heating the adherend under conditions of 200 ° C. or higher) and a peeling step of peeling the adhesive material from the adherend that has undergone the heating step. The adherend is, for example, a silicon wafer. Since the adhesive layer of the adhesive material (heat resistant adhesive material) according to the present embodiment can maintain adhesiveness even in a high-temperature environment, it can be used for applications including such a pasting step and a heating step.

  In the attaching step, the heat-resistant adhesive material is attached to the adherend so that the adhesive layer is disposed on the side close to the adherend. Moreover, in a sticking process, a heat resistant adhesive material can be affixed on a to-be-adhered body by pressing so that the adhesion layer and adherend of a heat-resistant adhesive material may contact | connect. If a double-sided heat-resistant adhesive material is used, a plurality of adherends can be attached. At this time, the plurality of adherends may be the same as or different from each other.

  In the attaching step, for example, the heat-resistant adhesive material and the adherend can be attached at an arbitrary temperature. For example, it can be attached at 0 to 100 ° C. from the viewpoint of appropriate adhesive expression and work efficiency. desirable.

  In the heating step, for example, the heat-resistant adhesive material and the adherend are heated. Although the heating method and the purpose of heating are not particularly limited, the adhesive layer is exposed to a temperature of 200 ° C. or higher by the heating. Usually, when a heat-resistant adhesive having low heat resistance (for example, an acrylic heat-resistant adhesive) is subjected to such a heating step, the adhesiveness is not maintained, and floating or peeling occurs. However, according to the pressure-sensitive adhesive layer containing the heat-resistant pressure-sensitive adhesive according to the present embodiment, the adhesiveness is maintained even after such a heating step, so that the occurrence of floating and peeling can be sufficiently suppressed.

  In the heating step, the heated adherend may be molded. Since the pressure-sensitive adhesive layer containing the heat-resistant pressure-sensitive adhesive according to the present embodiment is excellent in followability, even when the adherend is deformed by molding, the occurrence of lifting or peeling is sufficiently suppressed.

  Moreover, even if the said heating process may be repeated in multiple times and a heating method and the objective of a heating differ, generation | occurrence | production of a float or peeling is fully suppressed.

  Next, the peeling process after use of a heat-resistant adhesive is illustrated. In the peeling step, the heat-resistant adhesive can be lifted up and peeled off from the adherend. In addition, the adhesive layer may be integrated with one of the adherend and the support, and may be peeled off from the other of the adherend and the support, or may be peeled independently. Although there is no restriction | limiting in particular in peeling temperature, 0-200 degreeC is preferable and it is preferable to peel at 20-50 degreeC on the efficiency of work.

  Furthermore, depending on the peeling method, an additive can be added, for example, by adding a UV initiator, a UV peeling compatible material, a light absorbing material can be added to make a laser peeling compatible material, Applicable to various peeling methods.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to an Example.

(Synthesis Example 1)
43.75 parts (molar ratio) of isophthaloyl dichloride, 6.25 parts of terephthaloyl dichloride, 5 parts of polypropylene glycol diamine (JEFFAMINE (registered trademark) D-2000, manufactured by HUNTSMAN), 1,4-bis (3-aminopropyl) ) 45 parts of piperazine and 110 parts of triethylamine were added and subjected to condensation polymerization in N-methylpyrrolidone. After completion of the reaction, a polyamide resin was obtained by adding 3 times the amount of water to the reaction mixture, separating insoluble components and drying. The weight average molecular weight of this polyamide resin was 38500.

(Synthesis Example 2)
40 parts (molar ratio) of isophthaloyl dichloride, 10 parts of terephthaloyl dichloride, 5 parts of polypropylene glycol diamine (JEFFAMINE (registered trademark) D-2000, manufactured by HUNTSMAN), 40 parts of 1,4-bis (3-aminopropyl) piperazine 4,4′-diaminodicyclohexylmethane (Wandamine HM (trade name), manufactured by Shin Nippon Rika Co., Ltd.) and 110 parts of triethylamine were added and subjected to condensation polymerization in N-methylpyrrolidone. After completion of the reaction, a polyamide resin was obtained by adding 3 times the amount of water to the reaction mixture, separating insoluble components and drying. The weight average molecular weight of this polyamide resin was 41000.

(Sample preparation)
Based on the formulation shown in Table 1 and Table 2, a compound containing boron or a compound containing no boron is added to the polyamide resin obtained in Synthesis Example 1 or 2, and the solvent is adjusted so as to have a solid content of 30% by mass. N, N′-dimethylacetamide was added and stirred for 5 minutes with a high-speed rotating machine (1200 rpm) to obtain an adhesive varnish.

  In Table 1, ASF1109 (manufactured by Asahi Glass Co., Ltd.) is a compound containing boron. In Table 2, ASF1560 (manufactured by Asahi Glass Co., Ltd.) and HS-100 (manufactured by Denki Kagaku Kogyo Co., Ltd.) are compounds not containing boron. The average particle size is a particle size of D50. In Table 1, a compound having “−” as an average particle diameter is dissolved in the adhesive varnish. The addition amount shown in Table 1 and Table 2 shows content based on solid content in the adhesion layer mentioned later.

  The obtained adhesive varnish was applied to a polyimide film with a thickness of 25 μm using an applicator so that the adhesive layer after drying was 15 cm square and the thickness after drying was 25 μm, and heated at 160 ° C. for 30 minutes. And dried to produce an adhesive. Next, the obtained adhesive material is placed on a 10 μm × 10 cm glass plate having a thickness of 700 μm, and a laminator having a roll temperature of 50 ± 5 ° C. and a roll pressure of 0.3 MPa is passed at a speed of 0.4 m / min. Pasted.

(Examples and comparative examples)
Tables 1 and 2 show the compositions used in Examples and Comparative Examples and the evaluation results of the following evaluations. The evaluation method is as follows.

[Film forming ability]
Observe the surface of the pressure-sensitive adhesive layer obtained by coating, ◯ if the surface is flat, △ if there is a rugged shape on a part of the surface, and if there is a rugged shape on almost the entire surface X was evaluated.

[Attachability to wafer]
The adhesive material affixed on glass was observed visually from the glass side, and the presence or absence of the space | gap was confirmed. The case where the porosity was 10% or less was evaluated as ◯, the case where the porosity was more than 10% but not more than 30% was evaluated as Δ, and the case where the porosity was more than 30% was evaluated as ×. In addition, the porosity was calculated by the ratio with respect to the area (10 cm x 10 cm) of an adhesive material, reading the rough void area visually.

[Heat-resistant]
The adhesive material affixed to the glass was heated at 250 ° C./30 minutes in a hot air drying furnace, and the appearance of the adhesive layer was observed. The case where there was no change before and after heating was evaluated as ◯, and the case where swelling or voids was formed was evaluated as ×.

[Wafer peel strength]
The strength when peeling the adhesive material (adhesive material affixed to glass) subjected to heat resistance evaluation from the glass surface was measured. The peel strength was measured by pulling an adhesive material having a width of 10 mm at a rate of 300 mm / min in the 90 ° direction at 25 ° C. In addition, when the heat resistance evaluation was low, the wafer peel strength was not evaluated.

(Evaluation results)
In the examples, film forming ability, stickability to wafer, heat resistance, and peel strength against wafer were all good, and it was confirmed that both heat resistance and peelability could be achieved. On the other hand, in the comparative example, the heat resistance or the peel strength against the wafer was inferior, and it was confirmed that the heat resistance and the peelability were not compatible.

  As described above, by combining a specific condensation resin and a boron-containing compound, it is possible to provide a heat-resistant adhesive having both excellent heat resistance and peelability.

Claims (22)

  A pressure-sensitive adhesive comprising a condensation resin and a compound containing boron.   The pressure-sensitive adhesive according to claim 1, wherein the condensation resin has a polyoxyalkanediyl group.   The pressure-sensitive adhesive according to claim 1 or 2, wherein the condensation resin has a 1,4-piperazinediyl group.   The condensation resin is at least one monomer (A) selected from the group consisting of a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halide of the carboxylic acid; The pressure-sensitive adhesive according to any one of claims 1 to 3, comprising a structural unit obtained by condensation polymerization of a polymerizable monomer containing a monomer (B) having at least two amino groups.   The monomer (B) includes a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups, and a monomer (b2) having a 1,4-piperazinediyl group and at least two amino groups. The pressure-sensitive adhesive according to claim 4.   The pressure-sensitive adhesive according to claim 5, wherein the content of the monomer (b1) in the polymerizable monomer is 0.5 to 20 mol% based on the total amount of the monomer (A) and the monomer (B).   The pressure-sensitive adhesive according to any one of claims 4 to 6, wherein the monomer (B) includes a monomer having a cyclohexyl group and at least two amino groups.   The pressure-sensitive adhesive according to any one of claims 4 to 7, wherein the monomer (A) has a divalent aromatic ring group.   The condensation resin comprises at least one monomer (A) selected from the group consisting of a carboxylic acid having at least two carboxyl groups, an anhydride of the carboxylic acid, an esterified product of the carboxylic acid, and a halide of the carboxylic acid. The pressure-sensitive adhesive according to any one of claims 1 to 3, comprising a structural unit (A) derived from and a structural unit (B) derived from a monomer (B) having at least two amino groups.   The structural unit (B) has a structural unit (b1) derived from a monomer (b1) having a polyoxyalkanediyl group and at least two amino groups, a 1,4-piperazinediyl group, and at least two amino groups. The pressure-sensitive adhesive according to claim 9, comprising a structural unit (b2) derived from the monomer (b2).   The pressure-sensitive adhesive according to claim 10, wherein the content of the structural unit (b1) is 0.5 to 20 mol% based on the total amount of the structural unit (A) and the structural unit (B).   The pressure-sensitive adhesive according to any one of claims 9 to 11, wherein the structural unit (B) includes a structural unit having a cyclohexyl group.   The pressure-sensitive adhesive according to any one of claims 9 to 12, wherein the structural unit (A) has a divalent aromatic ring group.   The said carboxylic acid in said monomer (A), its anhydride, and at least 1 type chosen from the group which consists of said monomer (B) are liquid state at any one of Claims 4-13. Adhesive.   The pressure-sensitive adhesive according to any one of claims 1 to 14, wherein the condensed resin has a divalent aromatic ring group.   The pressure-sensitive adhesive according to any one of claims 1 to 15, which is used as a heat-resistant pressure-sensitive adhesive that is attached to an adherend and heated from 200 ° C or higher and then peeled off from the adherend.   The pressure-sensitive adhesive according to any one of claims 1 to 16, wherein the content of the condensation resin is 50% by mass or more based on the total solid content of the pressure-sensitive adhesive. A support, and an adhesive layer provided on the support,
The adhesive material in which the said adhesion layer contains the adhesive as described in any one of Claims 1-17. An attaching step of attaching the first adherend to the second adherend via the adhesive layer containing the adhesive according to any one of claims 1 to 17,
A heating step of heating the first adherend and the second adherend under conditions where the temperature of the adhesive layer is 200 ° C. or higher;
A method of using a pressure-sensitive adhesive comprising: a peeling step of peeling the pressure-sensitive adhesive layer and the second adherend from the first adherend subjected to the heating step.   The method of using an adhesive according to claim 19, wherein at least one of the first adherend and the second adherend is a silicon wafer. A sticking step of sticking the adhesive layer of the adhesive material according to claim 18 to an adherend;
A heating step of heating the adherend under conditions where the temperature of the adhesive layer is 200 ° C. or higher;
A method of using an adhesive material, comprising: a peeling step of peeling the adhesive material from the adherend that has undergone the heating step.   The method for using an adhesive material according to claim 21, wherein the adherend is a silicon wafer.