WO2024029315A1 - Method for producing (meth)acrylic resin and method for producing adhesive composition - Google Patents

Method for producing (meth)acrylic resin and method for producing adhesive composition Download PDF

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Publication number
WO2024029315A1
WO2024029315A1 PCT/JP2023/026014 JP2023026014W WO2024029315A1 WO 2024029315 A1 WO2024029315 A1 WO 2024029315A1 JP 2023026014 W JP2023026014 W JP 2023026014W WO 2024029315 A1 WO2024029315 A1 WO 2024029315A1
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meth
group
acrylic resin
adhesive layer
producing
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PCT/JP2023/026014
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French (fr)
Japanese (ja)
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耕治 直田
佑哉 今井
晃暉 丸野
一博 佐々木
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株式会社レゾナック
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F8/00—Chemical modification by after-treatment
    • C08F8/30—Introducing nitrogen atoms or nitrogen-containing groups
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/62—Polymers of compounds having carbon-to-carbon double bonds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
    • C08G59/18—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
    • C08G59/40—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing characterised by the curing agents used
    • C08G59/62—Alcohols or phenols
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J163/00—Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J175/00—Adhesives based on polyureas or polyurethanes; Adhesives based on derivatives of such polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26

Definitions

  • the content of the present disclosure relates to a method for producing a (meth)acrylic resin used in a pressure-sensitive adhesive composition and a method for producing a pressure-sensitive adhesive composition.
  • Adhesive compositions used in the adhesive layer of removable adhesive sheets include those containing resins in which UV (ultraviolet rays) curable ethylenically unsaturated groups are introduced into the side chains of (meth)acrylic resins.
  • Such an adhesive composition undergoes a crosslinking reaction and is cured by UV irradiation, resulting in a decrease in adhesive strength.
  • Patent Document 1 Japanese Unexamined Patent Application Publication No. 2018-138682 describes a living radical polymerization polymer having a molecular weight distribution (Mw/Mn) of 1.05 to 2.5, particularly a living radical polymerization polymer using an organic tellurium polymerization initiator.
  • An adhesive tape containing a (meth)acrylic polymer in which a polymerizable group that can be cured by ultraviolet rays is introduced into the side chain of the polymer obtained by the method is described.
  • a dicing/die bond integrated film is used, which is a film in which a dicing tape, which is a removable adhesive sheet, and a die bond (adhesive layer) are integrated.
  • This film is used, for example, by attaching an adhesive layer to the back surface of a semiconductor wafer and attaching an adhesive layer derived from a dicing tape to a dicing ring. Thereafter, the semiconductor wafer is diced using a dicing blade to obtain individualized semiconductor chips.
  • the adhesive layer derived from the dicing tape is required to have high adhesion to the adhesive layer and the dicing ring in the dicing process, but in the semiconductor chip pickup process, adhesive residue (adhesive residue) is left on each semiconductor chip. It is required to be able to easily pick up semiconductor chips with adhesive pieces. If the adhesion of the adhesive layer to the adhesive layer is insufficient, the high-speed rotation of the dicing blade will cause peeling between the adhesive layers and break the adhesive layer, resulting in broken edges of the adhesive layer. A scattering phenomenon (DAF (Die Attach Film) flying) occurs. If the adhesive force of the adhesive layer to the dicing ring is insufficient, a phenomenon in which the dicing ring peels off from the adhesive layer (ring peeling) occurs due to the flow of cutting water.
  • DAF Die Attach Film
  • stealth dicing has been attracting attention as a dicing method that does not use a dicing blade.
  • a laser beam is focused inside the wafer to form a starting point (modified layer) for dividing the wafer, a removable adhesive sheet is attached to the back of the wafer, and this sheet is cooled and expanded. , obtain singulated semiconductor chips.
  • the wafer and adhesive layer are separated into pieces by cooling expansion.
  • the outer periphery of the adhesive layer may break due to the impact and stress during expansion, causing the phenomenon of scattering of pieces (DAF flying) or the adhesion. Peeling between the edge of the chip with the adhesive and the adhesive layer (chip edge peeling) may occur, causing problems in subsequent steps.
  • the adhesive layer used in the dicing/die-bonding integrated film has high adhesion to the adhesive layer and can be easily peeled off from the adhesive layer without leaving any adhesive residue after UV irradiation. Characteristics that are not required for releasable pressure-sensitive adhesive sheets are required. Therefore, it is difficult to apply the acrylic pressure-sensitive adhesive conventionally used in removable pressure-sensitive adhesive sheets to a dicing/die-bonding integrated film as is.
  • the present disclosure has sufficient adhesion to the adhesive layer, and when the adhesive sheet is peeled off from the adhesive layer after UV irradiation, excellent peelability is obtained and no adhesive remains.
  • a manufacturing method capable of obtaining a (meth)acrylic resin or a pressure-sensitive adhesive composition containing a (meth)acrylic resin that can provide a pressure-sensitive adhesive layer that is difficult to peel.
  • the present inventors used a copolymer obtained by reversible addition fragmentation chain transfer (RAFT) polymerization of a hydroxy group-containing (meth)acrylate and an alkyl (meth)acrylate with an isocyanato group-containing ethylenically unsaturated compound. It has been found that a modified polymer can be suitably used in the adhesive layer of a dicing/die-bonding integrated film.
  • RAFT reversible addition fragmentation chain transfer
  • a copolymer is obtained by polymerizing a raw material monomer group (M) containing a hydroxy group-containing (meth)acrylate (m-1) and an alkyl (meth)acrylate (m-2) by reversible addition-fragmentation chain transfer (RAFT).
  • An isocyanato group-containing ethylenically unsaturated compound (a) is added to a part of the side chain hydroxyl groups of the copolymer (A-0) to produce a (meth)acrylic resin (A) having an ethylenically unsaturated group.
  • Step (ii) of obtaining A method for producing a (meth)acrylic resin containing [2] The method for producing a (meth)acrylic resin according to [1], wherein the raw material monomer group (M) further contains a carboxy group-containing monomer (m-3). [3] The (meth)acrylic resin according to [1] or [2], wherein the (meth)acrylic resin (A) having an ethylenically unsaturated group has a molecular weight distribution (Mw/Mn) of 2.4 to 10.0. Production method.
  • a (meth)acrylic resin (A) having an ethylenically unsaturated group obtained by the production method according to any one of [1] to [3], a photopolymerization initiator (B), and a crosslinking agent (C) A method for producing an adhesive composition, comprising the step (iii) of mixing. [5] The method for producing an adhesive composition according to [4], wherein the crosslinking agent (C) is at least one selected from the group consisting of polyisocyanates and polyepoxy compounds. [6] [4] or [5] A method for producing an adhesive layer, comprising a step of forming a crosslinked structure in the adhesive composition obtained by the production method according to [5].
  • a method for producing a pressure-sensitive adhesive sheet comprising applying the pressure-sensitive adhesive composition obtained by the production method according to [4] or [5] to a sheet-like base material to prepare a pressure-sensitive adhesive layer.
  • a method for producing a pressure-sensitive adhesive sheet comprising a step of forming a crosslinked structure in the pressure-sensitive adhesive layer obtained by the method according to [7].
  • [10] [4] or [5] A method for producing an integrated dicing and die bonding film, the method comprising applying the pressure-sensitive adhesive composition obtained by the production method according to [5] to an adhesive layer.
  • the (meth)acrylic resin obtained by the method of the present disclosure in the adhesive layer of the dicing/die-bonding integrated film, it has sufficient adhesion to the adhesive layer and is sticky after UV irradiation.
  • the sheet is peeled off from the adhesive layer, it is possible to obtain an adhesive layer that exhibits excellent peelability and is less likely to leave adhesive residue.
  • (meth)acrylic means methacrylic or acrylic
  • (meth)acrylate means acrylate or methacrylate
  • (meth)acryloyloxy means acryloyloxy or methacryloyloxy. do.
  • weight average molecular weight and “number average molecular weight” are measured at room temperature (23°C) using gel permeation chromatography (GPC) under the following conditions, and a standard polystyrene calibration curve is used.
  • GPC gel permeation chromatography
  • glass transition temperature refers to the temperature of a sample taken from -100°C to 200°C at a heating rate of 10°C/min using a differential scanning calorimeter (DSC). Differential scanning calorimetry was performed while changing the temperature, and this is the observed temperature at which endotherm begins due to glass transition. If two or more endothermic onset temperatures are observed, Tg is the simple average value of the two or more endothermic onset temperatures.
  • a method for producing a (meth)acrylic resin (A) having an ethylenically unsaturated group includes hydroxyl group-containing (meth)acrylate (m-1), and A copolymer (A-0) is obtained by subjecting a raw material monomer group (M) containing an alkyl (meth)acrylate (m-2) to reversible addition-fragmentation chain transfer (RAFT) polymerization.
  • RAFT addition-fragmentation chain transfer
  • the raw material monomer group (M) may contain a carboxy group-containing monomer (m-3).
  • the copolymer (A-0) is prepared by combining a hydroxy group-containing (meth)acrylate (m-1) and an alkyl (meth)acrylate (m-2) in the presence of a reversible addition-fragmentation chain transfer agent (RAFT agent), It can also be obtained by RAFT polymerizing a raw material monomer group (M) optionally containing a carboxy group-containing monomer (m-3).
  • RAFT polymerization refers to radical polymerization performed in the presence of a RAFT agent.
  • RAFT polymerization is a type of living radical polymerization.
  • Living radical polymerization is generally known as a polymerization method capable of obtaining a polymer with a small molecular weight distribution, and specific examples thereof include atom transfer radical polymerization, organic tellurium-mediated radical polymerization, RAFT polymerization, and the like.
  • RAFT polymerization does not use halogens or heavy metals, so it has a low environmental impact and is suitable for semiconductor applications.
  • the copolymer (A-0) obtained by RAFT polymerization has a more appropriate molecular weight distribution than (meth)acrylic copolymers obtained by other living radical polymerizations.
  • the adhesive composition produced using the (meth)acrylic resin (A) obtained from the copolymer (A-0) has excellent wettability to the adhesive layer and high adhesion to the adhesive layer. have power. This is because the low molecular weight component of the (meth)acrylic resin (A) contributes to the wettability and fluidity of the adhesive composition. If the molecular weight distribution of the (meth)acrylic copolymer is too narrow, the resulting pressure-sensitive adhesive composition will have low fluidity and wettability with respect to the adhesive layer, and sufficient adhesion will not be obtained.
  • a solution polymerization method As the polymerization method, a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, a suspension polymerization method, an alternating copolymerization method, etc. can be used. Among these polymerization methods, in consideration of the addition reaction in step (ii), it is preferable to use the solution polymerization method in terms of ease of reaction.
  • the hydroxy group-containing (meth)acrylate (m-1) is not particularly limited as long as it has a hydroxy group and a (meth)acryloyloxy group.
  • hydroxyalkyl (meth)acrylates such as acrylate; (meth)acrylates having an aromatic ring and a hydroxyl group such as hydroxyphenyl (meth)acrylate and 2-hydroxy-3-phenoxypropyl (meth)acrylate;
  • hydroxyalkyl (meth)acrylates are preferred, hydroxyalkyl (meth)acrylates in which the hydroxyalkyl group has 1 to 6 carbon atoms are more preferred, and 2-hydroxyethyl More preferred are (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate.
  • the content of the hydroxy group-containing (meth)acrylate (m-1) is preferably 5 to 50 mol%, more preferably 10 to 40 mol%, based on 100 mol% of the raw material monomer group (M). , more preferably 15 to 35 mol%.
  • the content of the hydroxy group-containing (meth)acrylate (m-1) is 5 mol% or more, the (meth)acrylic resin (A) has sufficient hydroxy groups and the amount of crosslinking with the crosslinking agent (C) is Therefore, it is possible to obtain an adhesive layer having sufficient cohesive force.
  • reaction points for introducing ethylenically unsaturated groups can be secured, and better peelability can be obtained when the pressure-sensitive adhesive sheet is peeled off from the adherend after UV irradiation.
  • the content of the hydroxy group-containing (meth)acrylate (m-1) is 50 mol% or less, unintended progress of reaction in the adhesive composition can be suppressed, resulting in good storage stability. It is.
  • alkyl (meth)acrylate (m-2) The alkyl (meth)acrylate (m-2) is not particularly limited as long as it does not have a hydroxy group or a carboxy group and has an alkyl group and a (meth)acryloyloxy group.
  • the alkyl group in the alkyl (meth)acrylate (m-2) may be substituted.
  • the substituent include alkoxy groups such as methoxy and ethoxy groups.
  • alkyl (meth)acrylates and alicyclic alkyl (meth)acrylates in which the alkyl group has 1 to 20 carbon atoms are preferred, and methyl (meth)acrylate, Ethyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, ) acrylate and dicyclopentanyl (meth)acrylate are more preferred.
  • the content of alkyl (meth)acrylate (m-2) is preferably 10 to 94 mol%, more preferably 30 to 85 mol%, and further Preferably it is 50 to 80 mol%.
  • the content of alkyl (meth)acrylate (m-2) is 10 mol% or more, excellent adhesiveness can be obtained.
  • the content of alkyl (meth)acrylate (m-2) is 94 mol% or less, a sufficient content of hydroxyl groups and ethylenically unsaturated groups in the (meth)acrylic resin (A) can be ensured. Therefore, an adhesive layer having well-balanced physical properties can be obtained from the viewpoint of the cohesive force of the adhesive layer and the peelability of the adhesive sheet after UV irradiation.
  • the carboxyl group-containing monomer (m-3) is not particularly limited as long as it does not have a hydroxyl group and has a carboxyl group and an ethylenically unsaturated group.
  • unsaturated monobasic acids such as (meth)acrylic acid, crotonic acid, vinylbenzoic acid, ⁇ -haloalkyl, alkoxyl, halogen, nitro, or cyano substituted products of acrylic acid, and unsaturated dibasic acids such as itaconic acid. can be mentioned.
  • (meth)acrylic acid is preferred from the viewpoint of ease of production of the adhesive.
  • the content of the carboxy group-containing monomer (m-3) is preferably 0.1 to 0.1 to 100 mol% of the raw material monomer group (M).
  • the content is 10 mol%, more preferably 0.5 to 8.0 mol%, even more preferably 1.0 to 5.0 mol%.
  • the content of the carboxy group-containing monomer (m-3) is 0.1 mol% or more, a sufficient amount of crosslinking can be ensured when the crosslinking agent (C) is a polyepoxy compound. , sufficient cohesive force of the adhesive can be obtained.
  • the raw material monomer group (M) may contain monomers (m-4) other than (m-1) to (m-3).
  • monomers (m-4) include dienes such as butadiene and dicyclopentadiene, styrenes, unsaturated dicarboxylic acid diesters, and other vinyl compounds.
  • styrenes include styrene, ⁇ -, o-, m-, or p-alkyl derivatives of styrene.
  • unsaturated dicarboxylic acid diesters include diethyl citraconate, diethyl maleate, diethyl fumarate, diethyl itaconate, and the like.
  • vinyl compounds include norbornene (bicyclo[2.2.1]hept-2-ene), 5-methylbicyclo[2.2.1]hept-2-ene, 5-ethylbicyclo[ 2.2.1] hept-2-ene, tetracyclo[4.4.0.1 2,5 . 1 7,10 ] dodec-3-ene, 8-methyltetracyclo[4.4.0.1 2,5 . 1 7,10 ] dodec-3-ene, 8-ethyltetracyclo[4.4.0.1 2,5 .
  • RAFT agent Reversible addition-fragmentation chain transfer agent
  • any known RAFT agent can be used without particular limitation.
  • sulfur-based compounds trithiocarbonate, dithioester, dithiocarbonate, and dithiocarbamate
  • formula (1), formula (2), formula (3), or formula (4) are preferred.
  • R 1a and R 1b are the same or different and represent a hydrogen atom, a hydrocarbon group, a carboxy group, or a cyano group, and R 1c is substituted with a cyano group, a cyano group, or a carboxy group.
  • R2 represents a saturated or unsaturated aliphatic hydrocarbon group that may be substituted with a carboxy group, or a phenyl group that may be substituted; Indicates a hydrocarbon group or an optionally substituted benzyl group.
  • R 3a and R 3b are the same or different and represent a hydrogen atom, a hydrocarbon group, or a cyano group, and R 3c is a carboxy group, an acetoxymethyl group, a cyano group, or a carboxy group. represents a hydrocarbon group that may be substituted, and R 4 represents a hydrocarbon group.
  • R 5a and R 5b are the same or different and are a hydrogen atom, a hydrocarbon group, a carboxy group which may be substituted with a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms, or a cyano (R 5c represents a hydrocarbon group which may be substituted with an alkoxy group, and R 6 represents a hydrocarbon group.)
  • R 7a and R 7b are the same or different and represent a hydrogen atom or a hydrocarbon group
  • R 7c is a cyano group
  • R 8 and R 9 are the same or different, It may represent a hydrocarbon group, or R 8 and R 9 may combine to form a pyrazole ring which may be substituted with a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms or a chlorine atom.
  • the hydrocarbon group represented by R 1a and R 1b includes, for example, a straight chain, branched or cyclic, saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, Among these, straight chain, branched or cyclic, saturated or unsaturated hydrocarbon groups having 1 to 12 carbon atoms are preferred.
  • the hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a cyclohexyl group, a dodecyl group, an octadecyl group, etc.
  • the saturated or unsaturated aliphatic hydrocarbon group represented by R 1c is, for example, a linear, branched or cyclic saturated or unsaturated aliphatic hydrocarbon group having 1 to 20 carbon atoms. Hydrogen groups are mentioned, and among them, linear, branched or cyclic, saturated or unsaturated aliphatic hydrocarbon groups having 1 to 12 carbon atoms are preferred.
  • Examples of the aliphatic hydrocarbon group include carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, cyclohexyl group, dodecyl group, and octadecyl group.
  • Examples include 1 to 20 linear, branched, or cyclic saturated aliphatic hydrocarbon groups.
  • 1 to 3 hydrogen atoms of the saturated or unsaturated aliphatic hydrocarbon group represented by R 1c may be substituted with a carboxy group or a cyano group, and the carboxy group is a carbon It may be further substituted with a saturated aliphatic hydrocarbon group having 1 to 3 atoms.
  • substituents for the optionally substituted phenyl group represented by R 1c include a substituted carbamoyl group, an alkoxycarbonyl group having 2 to 5 carbon atoms which may be substituted with a hydroxy group, and a carbon atom number Examples include 3 to 5 alkenyloxycarbonyl groups.
  • the substituent of the substituted carbamoyl group examples include a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a hydroxy group or an acetyloxy group.
  • the saturated or unsaturated aliphatic hydrocarbon group represented by R 2 is, for example, a linear, branched or cyclic saturated or unsaturated aliphatic hydrocarbon group having 1 to 20 carbon atoms. Examples include hydrogen groups, and among them, aliphatic hydrocarbon groups having 1 to 12 carbon atoms are preferred.
  • Examples of the aliphatic hydrocarbon group include carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, cyclohexyl group, dodecyl group, and octadecyl group.
  • Examples include 1 to 20 linear, branched, or cyclic saturated aliphatic hydrocarbon groups.
  • 1 to 3 hydrogen atoms of the saturated or unsaturated aliphatic hydrocarbon group represented by R 2 may be substituted with a carboxy group.
  • substituents for the optionally substituted benzyl group represented by R 2 include a substituted carbamoyl group, an alkoxycarbonyl group having 2 to 5 carbon atoms which may be substituted with a hydroxy group, and a carbon atom number Examples include 3 to 5 alkenyloxycarbonyl groups.
  • substituent of the substituted carbamoyl group include a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a hydroxy group or an acetyloxy group.
  • R 1a and R 1b are the same or different and are a hydrogen atom, a hydrocarbon group having 1 to 4 carbon atoms, or a carboxy group
  • R 1c is a hydrocarbon group having 1 to 4 carbon atoms, or a phenyl group which may be substituted
  • R 2 is a linear, branched or cyclic, saturated or unsaturated aliphatic hydrocarbon group having 1 to 20 carbon atoms, or a benzyl group which may be substituted.
  • a compound represented by a certain formula (1) is preferred, in which R 1a and R 1b are a hydrogen atom, a combination of a methyl group or an ethyl group, and a carboxy group, or a hydrogen atom, and R 1c is a methyl group, an ethyl group, or a phenyl group which may be substituted, and a compound represented by formula (1) in which R 2 is a linear saturated aliphatic hydrocarbon group having 1 to 20 carbon atoms, or a benzyl group which may be substituted; More preferred.
  • the hydrocarbon group represented by R 3a , R 3b , R 3c and R 4 is, for example, a linear, branched or cyclic, saturated or unsaturated carbonized group having 1 to 20 carbon atoms. Hydrogen groups are mentioned, and among them, straight chain, branched or cyclic, saturated or unsaturated hydrocarbon groups having 1 to 12 carbon atoms are preferred.
  • hydrocarbon group examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a cyclohexyl group, a dodecyl group, an octadecyl group, etc. ⁇ 20 linear, branched or cyclic saturated aliphatic hydrocarbon groups; aryl groups with 6 to 12 carbon atoms such as phenyl groups; arylalkyl groups with 7 to 10 carbon atoms such as benzyl groups and phenethyl groups, etc. can be mentioned.
  • the hydrocarbon group which may be substituted with a cyano group or a carboxy group represented by R 3c is, for example, a hydrocarbon group in which 1 to 3 of the hydrogen atoms of the above-mentioned hydrocarbon group are cyano groups or carboxy groups. Examples include groups substituted with .
  • R 3a and R 3b are the same or different and are linear saturated hydrocarbon groups having 1 to 4 carbon atoms
  • R 3c is an aryl group
  • R 4 is an aryl group or a benzyl group.
  • a compound represented by a certain formula (2) is preferred, in which R 3a and R 3b are the same or different and are a methyl group or an ethyl group, R 3c is a phenyl group, and R 4 is a phenyl group or a benzyl group.
  • a compound represented by formula (2) is more preferred.
  • the hydrocarbon group represented by R 5a , R 5b , R 5c and R 6 is, for example, a linear, branched or cyclic, saturated or unsaturated carbonized group having 1 to 20 carbon atoms. Hydrogen groups are mentioned, and among them, straight chain, branched or cyclic, saturated or unsaturated hydrocarbon groups having 1 to 12 carbon atoms are preferred.
  • hydrocarbon group examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a cyclohexyl group, a dodecyl group, an octadecyl group, etc. ⁇ 20 linear, branched or cyclic saturated aliphatic hydrocarbon groups; aryl groups with 6 to 12 carbon atoms such as phenyl groups; arylalkyl groups with 7 to 10 carbon atoms such as benzyl groups and phenethyl groups, etc. can be mentioned.
  • the hydrocarbon group which may be substituted with an alkoxy group represented by R 5c includes, for example, a group in which 1 to 3 of the hydrogen atoms of the above-mentioned hydrocarbon group are substituted with an alkoxy group. can be mentioned.
  • the hydrocarbon group represented by R 7a , R 7b , R 8 and R 9 is, for example, a linear, branched or cyclic, saturated or unsaturated carbonized group having 1 to 20 carbon atoms. Hydrogen groups are mentioned, and among them, linear, branched or cyclic, saturated or unsaturated hydrocarbon groups having 1 to 12 carbon atoms are preferred.
  • hydrocarbon group examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a cyclohexyl group, a dodecyl group, an octadecyl group, etc. ⁇ 20 linear, branched, or cyclic saturated aliphatic hydrocarbon groups; aryl groups with 6 to 12 carbon atoms such as phenyl groups; arylalkyl groups with 7 to 10 carbon atoms such as benzyl groups and phenethyl groups, etc. can be mentioned.
  • R 8 and R 9 may form a pyrazole ring together with the nitrogen atom of formula (4).
  • the pyrazole ring may be substituted with a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms or a chlorine atom.
  • RAFT agents shown in formulas (1) to (4) When polymerization is carried out in the presence of the RAFT agents shown in formulas (1) to (4), radical species undergo a chain reaction between the sulfur atoms in the RAFT agent and the carbon atoms adjacent to the sulfur atoms, leading to polymerization. proceed.
  • RAFT agents represented by formulas (1) and (2) are preferred from the viewpoint of ease of polymerization.
  • RAFT agents are commercially available. Those that are not commercially available can be easily synthesized by known or conventional methods.
  • RAFT agents include S-cyanomethyl-S-dodecyl trithiocarbonate, 2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propanoic acid, 2- ⁇ [(2-carboxyethyl)sulfanylthiocarbonyl]sulfanyl ⁇ propane.
  • Dithioester ethyl 2-[(ethoxycarbonothioyl)thio]propionate, O-ethyl-S-(2-propoxyethyl)dithiocarbonate, O-ethyl-S-(1-cyano-1-methylethyl)dithio Dithiocarbonates such as carbonate; 2-cyano-2-propyldiethyldithiocarbamate, 2'-cyanobutan-2'-yl 4-chloro-3,5-dimethylpyrazole-1-dithiocarbamate, 2'-cyanobutane-2 Examples include dithiocarbamates such as '-yl 3,5-dimethylpyrazole-1-dithiocarbamate, cyanomethyl 3,5-dimethylpyrazole-1-dithiocarbamate, and cyanomethyl N-methyl-N-phenyldithiocarbamate.
  • trithiocarbonate and dithioester are preferred from the viewpoint of ease of polymerization of the (meth)acrylic resin (A), and 2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propanoic acid, 2- ⁇ [(2 -carboxyethyl)sulfanylthiocarbonyl]sulfanyl ⁇ propanoic acid, 2-phenyl-2-propyldithiobenzoic acid, S,S-dibenzyltrithiocarbonate, and bis ⁇ 4-[ethyl-(2-acetyloxyethyl)carbamoyl) ]benzyl ⁇ trithiocarbonate is more preferred.
  • RAFT agents may be used alone or in combination of two or more.
  • radical polymerization initiator RAFT polymerization is preferably performed in the presence of a radical polymerization initiator.
  • the radical polymerization initiator include ordinary organic radical polymerization initiators, specifically, for example, 2,2'-azobis(isobutyronitrile), 2,2'-azobis(4- methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane) -1-carbonitrile), 2,2'-azobis(2,4,4-trimethylpentane), dimethyl-2,2'-azobis(2-methylpropionate), and other azo polymerization initiators; and benzoyl Peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, t-butyl peroxybenzoate, dicumyl peroxide, 1,1-bis(t-butyl hydro
  • the radical polymerization initiators may be used alone or in combination of two or more.
  • the amount of the radical polymerization initiator used is preferably 0.001 to 5 parts by mass, more preferably 0.005 to 3 parts by mass, based on 100 parts by mass of the total amount of the raw material monomer group (M). , more preferably 0.01 to 1 part by mass.
  • solvent As the solvent used for RAFT polymerization, common solvents can be used.
  • solvents include esters such as ethyl acetate, propyl acetate, and butyl acetate; aromatic hydrocarbons such as toluene, xylene, and benzene; aliphatic hydrocarbons such as hexane and heptane; and alicyclic carbonization such as cyclohexane and methylcyclohexane.
  • Ketones such as methyl ethyl ketone and methyl isobutyl ketone
  • Glycols such as ethylene glycol, propylene glycol and dipropylene glycol
  • Glycol ethers such as methyl cellosolve, propylene glycol monomethyl ether and dipropylene glycol monomethyl ether
  • ethylene glycol diacetate and propylene glycol examples include glycol esters such as monomethyl ether acetate.
  • the solvents may be used alone or in combination of two or more.
  • reaction temperature for RAFT polymerization depends on the type of radical polymerization initiator used, but is usually 30°C to 130°C, preferably 40°C to 120°C, more preferably 50°C to 110°C. preferable. When the temperature during RAFT polymerization is 30° C. or higher, a sufficient reaction rate can be obtained. When the temperature during RAFT polymerization is 130° C. or lower, there is little risk during production.
  • the reaction time for RAFT polymerization depends on the raw material monomer group (M) used, the RAFT agent, and the type of radical polymerization initiator, but is usually 3 to 30 hours, preferably 4 to 20 hours. , more preferably from 5 hours to 15 hours.
  • the reaction time is 3 hours or more, the copolymer (A-0) can be produced from the raw material monomer group (M) with an appropriate degree of polymerization, and when the reaction time is 30 hours or less, the copolymer (A-0) can be produced efficiently. Manufacturing can be carried out.
  • the (meth)acrylic resin (A) is an ethylenically unsaturated compound containing an isocyanato group in a part of the side chain hydroxyl group derived from the hydroxyl group-containing (meth)acrylate (m-1) possessed by the copolymer (A-0). Obtained by adding (a).
  • the isocyanato group-containing ethylenically unsaturated compound (a) is added to all of the side chain hydroxy groups of the copolymer (A-0), there will be no reaction sites with the crosslinking agent (C) described below, so the addition will be carried out only on the side chains. Only part of the hydroxyl group.
  • (Meth)acrylic resin (A) has ethylenically unsaturated groups in its side chains, so compared to (meth)acrylic copolymers with ethylenically unsaturated groups introduced at the ends, the molecular chain between crosslinking points is The length is relatively short, and the adhesive force can be greatly reduced after UV irradiation.
  • a pressure-sensitive adhesive sheet using (meth)acrylic resin (A) has excellent releasability from an adherend.
  • the adhesive composition manufactured using the methacrylic resin (A) has excellent adhesion to the adhesive layer. have Therefore, the adhesive composition manufactured using the (meth)acrylic resin (A) is suitably used in the adhesive layer of the dicing/die-bonding integrated film.
  • the molecular weight distribution (Mw/Mn) of the (meth)acrylic resin (A) is preferably 2.4 or more, more preferably 2.5 or more, and still more preferably 3.0 or more.
  • the molecular weight distribution of the (meth)acrylic resin (A) is preferably 10.0 or less, more preferably 6.0 or less, still more preferably 5.8 or less, even more preferably 5.6 or less. Any combination of these lower limit values and upper limit values may be used.
  • the molecular weight distribution of the (meth)acrylic resin (A) is preferably 2.4 to 10.0, more preferably 2.4 to 6.0, still more preferably 2.5 to 5.8, even more preferably 3. It is 0 to 5.6.
  • the molecular weight distribution is 2.4 or more, the wettability of the pressure-sensitive adhesive composition containing the (meth)acrylic resin (A) is improved, and the adhesiveness to the adherend, especially the adhesive layer, is good.
  • the molecular weight distribution is 10.0 or less, the (meth)acrylic resin (A) in the high molecular weight region falls within an appropriate range, making it easy to control the viscosity of the adhesive composition, and the (meth)acrylic resin (A) in the low molecular weight region falls within an appropriate range. ) By keeping the acrylic resin (A) within an appropriate range, adhesive residue is suppressed when the adhesive sheet is peeled off from the adherend.
  • the weight average molecular weight (Mw) of the (meth)acrylic resin (A) is preferably 100,000 or more, more preferably 150,000 or more, still more preferably 200,000 or more, even more preferably 300,000 or more.
  • the weight average molecular weight of the (meth)acrylic resin (A) is preferably 800,000 or less, more preferably 700,000 or less, even more preferably 650,000 or less. Any combination of these lower limit values and upper limit values may be used.
  • the weight average molecular weight (Mw) of the (meth)acrylic resin (A) is preferably 100,000 to 800,000, more preferably 150,000 to 700,000, and even more preferably 200,000 to 650. ,000, more preferably 300,000 to 650,000.
  • the weight average molecular weight is 100,000 or more, the peelability after UV irradiation is improved.
  • the weight average molecular weight is 800,000 or less, the viscosity of the adhesive composition containing the (meth)acrylic resin (A) can be appropriately suppressed, and the workability of the adhesive composition can be improved.
  • the ethylenically unsaturated group equivalent of the (meth)acrylic resin (A) is preferably 100 to 3,000 g/mol, more preferably 300 to 2,500 g/mol, even more preferably 500 to 2,000 g /mol. Within the above range, the amount of crosslinking of the adhesive composition during UV irradiation is sufficient, and the adhesive sheet produced using the (meth)acrylic resin (A) has excellent properties when peeled from the adherend. Excellent peelability and pick-up of small pieces of elements can be obtained.
  • the ethylenically unsaturated group equivalent of the (meth)acrylic resin (A) is the mass of the (meth)acrylic resin (A) per mole of ethylenically unsaturated bonds.
  • the ethylenically unsaturated group equivalent of the (meth)acrylic resin (A) in one embodiment is calculated from the amount charged, assuming that each raw material used in the production of the (meth)acrylic resin (A) has reacted 100%. This is the calculated value.
  • the ethylenically unsaturated group equivalent of the (meth)acrylic resin (A) may be calculated from the amount of halogen bonded to the (meth)acrylic resin (A).
  • the amount of halogen bonded to the (meth)acrylic resin (A) can be evaluated according to JIS K 0070:1992.
  • the glass transition temperature (Tg) of the (meth)acrylic resin (A) is preferably -80°C to 0°C, more preferably -70°C to -10°C, even more preferably -60°C to -30°C. It is °C.
  • Tg glass transition temperature
  • Tg glass transition temperature
  • the acid value of the (meth)acrylic resin (A) is preferably 0.5 to 100 mgKOH/g, more preferably is 1.0 to 50 mgKOH/g, more preferably 3.0 to 25 mgKOH/g.
  • the acid value is 0.5 mgKOH/g or more, a sufficient amount of crosslinking can be ensured when a polyepoxy compound is used as the crosslinking agent (C), and a sufficient cohesive force of the adhesive layer can be ensured.
  • the acid value is 100 mgKOH/g or less, the storage stability of the adhesive composition is good.
  • the acid value is a value measured according to JIS K 0070:1992.
  • the isocyanato group-containing ethylenically unsaturated compound (a) is not particularly limited as long as it is a compound that does not have a hydroxyl group or a carboxy group and has an isocyanato group and an ethylenically unsaturated group.
  • (meth)acrylic resin (A) (meth)acryloyloxyalkyl isocyanate is preferred, and 2-isocyanatoethyl (meth)acrylate is more preferred.
  • the content of the isocyanato group-containing ethylenically unsaturated compound (a) is preferably 0.25 mol or more, more preferably 0.50 mol or more, still more preferably 1. It is 0 or more.
  • the content of the isocyanato group-containing ethylenically unsaturated compound (a) is preferably 49 mol or less, more preferably 47 mol or less, still more preferably 45 mol or less. Any combination of these lower limit values and upper limit values may be used.
  • the content of the isocyanato group-containing ethylenically unsaturated compound (a) is preferably 0.25 to 49 mol, more preferably 0.50 to 47 mol, per 100 mol of the raw material monomer group (M).
  • the content of the isocyanato group-containing ethylenically unsaturated compound (a) is 0.25 mol or more, a sufficient amount of ethylenically unsaturated groups will be introduced into the (meth)acrylic resin (A), and the pressure-sensitive adhesive sheet will be formed after UV irradiation. It is possible to obtain better releasability when peeling off from an adherend.
  • the content of the isocyanato group-containing ethylenically unsaturated compound (a) is 49 mol or less, a sufficient content of hydroxyl groups in the (meth)acrylic resin (A) can be ensured, resulting in an excellent adhesive layer. A cohesive force can be obtained.
  • the amount of unreacted isocyanato group-containing ethylenically unsaturated compound (a) can be reduced, a pressure-sensitive adhesive sheet with less adhesive residue can be obtained.
  • a known catalyst can be used as necessary.
  • a urethanization catalyst such as dibutyltin dilaurate, titanium diisopropoxy bis(ethyl acetoacetate), tetrakis(2,4-pentanedionato)zirconium, bismuth tris(2-ethylhexanoate) is used. be able to.
  • the amount of the catalyst used is 0.01 parts by mass based on the total of 100 parts by mass of the copolymer (A-0) and the isocyanato group-containing ethylenically unsaturated compound (a). It is preferably from 10 parts by weight, more preferably from 0.02 to 5 parts by weight, even more preferably from 0.03 to 1 part by weight.
  • a known polymerization inhibitor in the addition reaction in step (ii), a known polymerization inhibitor can be used as necessary.
  • Known polymerization inhibitors can be used and are not particularly limited, but examples include 4-methoxyphenol, hydroquinone, methoquinone, 2,6-di-t-butylphenol, and 2,2'-methylenebis( (4-methyl-6-t-butylphenol) and phenothiazine. Polymerization inhibitors may be used alone or in combination of two or more.
  • the amount of the polymerization inhibitor used is based on the total of 100 parts by mass of the copolymer (A-0) and the isocyanato group-containing ethylenically unsaturated compound (a). , preferably 0.005 to 5 parts by weight, more preferably 0.03 to 3 parts by weight, and even more preferably 0.05 to 1.5 parts by weight. If the amount of the polymerization inhibitor used is 0.005 parts by mass or more, gelation during the addition reaction can be prevented. On the other hand, if the amount of the polymerization inhibitor used is 5 parts by mass or less, sufficient exposure sensitivity of the (meth)acrylic resin (A) upon UV irradiation can be obtained.
  • the temperature of the addition reaction is preferably 25°C to 130°C, particularly preferably 40°C to 120°C. When the temperature of the addition reaction is 25° C. or higher, a sufficient reaction rate can be obtained. When the temperature of the addition reaction is 130° C. or lower, it is possible to prevent double bonds from being crosslinked due to radical polymerization due to heat and from forming a gelled product.
  • a gas having a polymerization inhibiting effect may be introduced into the reaction system.
  • a gas having a polymerization inhibiting effect By introducing a gas having a polymerization inhibiting effect into the reaction system, gelation during the addition reaction can be prevented.
  • gases that have a polymerization inhibiting effect include gases that contain oxygen to an extent that does not fall within the explosive range of substances in the system, such as air.
  • the adhesive composition is prepared by mixing the (meth)acrylic resin (A), the photopolymerization initiator (B), the crosslinking agent (C), and other components added as necessary (iii). It can be manufactured by a method including.
  • the pressure-sensitive adhesive composition containing the (meth)acrylic resin (A) is suitably used for removable pressure-sensitive adhesive sheets, particularly for dicing and die-bonding integrated films.
  • the method of mixing each component contained in the adhesive composition is not particularly limited. Mixing can be performed using, for example, a stirring device equipped with a stirring blade such as a homodisper or a paddle blade.
  • Photopolymerization initiator (B) examples include benzophenone, benzyl, benzoin, ⁇ -bromoacetophenone, chloroacetone, acetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, p-dimethyl Aminoacetophenone, p-dimethylaminopropiophenone, 2-chlorobenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone, Michler's ketone, benzoin methyl ether, benzoin isobutyl ether, benzoin-n-butyl ether, benzyl Methyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-(4-isopropylphenyl)-2-hydroxy
  • Examples of the photopolymerization initiator (B) include sulfide photopolymerization initiators such as diphenyl disulfide, dibenzyl disulfide, tetraethylthiuram disulfide, and tetramethylammonium monosulfide; 2,4,6-trimethylbenzoyldiphenylphosphine oxide; , acylphosphine oxides such as 4,6-trimethylbenzoylphenylethoxyphosphine oxide; quinone-based photopolymerization initiators such as benzoquinone and anthraquinone; sulfochloride-based photopolymerization initiators; and thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, etc. Also included are thioxanthone photopolymerization initiators.
  • sulfide photopolymerization initiators such as diphenyl disulfide, dibenzyl dis
  • photoinitiators (B) carbonyl photoinitiators and acylphosphine oxides are preferred from the viewpoint of solubility in the adhesive composition, and 1-hydroxycyclohexylphenyl ketone and 2,4, It is more preferable to use at least one selected from 6-trimethylbenzoyldiphenylphosphine oxide.
  • the photopolymerization initiator (B) may be used alone or in combination of two or more types.
  • the photopolymerization initiator (B) is preferably 0.1 to 5.0 parts by mass, and 0.5 to 2.0 parts by mass, based on 100 parts by mass of the (meth)acrylic resin (A). It is more preferable.
  • the content of the photopolymerization initiator (B) is 0.1 parts by mass or more based on 100 parts by mass of the (meth)acrylic resin (A)
  • the adhesive composition can be cured at a sufficiently fast curing rate during UV irradiation. Therefore, the adhesive force of the adhesive layer after UV irradiation can be sufficiently reduced.
  • the adhesive sheet having the adhesive layer containing the adhesive composition cannot be adhered.
  • the adhesive layer is peeled off after being attached to the body, the adhesive layer is less likely to remain on the adherend. Even if the content of the photopolymerization initiator (B) exceeds 5.0 parts by mass with respect to 100 parts by mass of the (meth)acrylic resin (A), no effect commensurate with the content of the photopolymerization initiator (B) is observed. Therefore, by setting the content to 5.0 parts by mass or less, the adhesive composition can be economically produced.
  • the crosslinking agent (C) is a compound having no ethylenically unsaturated bond, and is a functional compound that reacts with the hydroxy group contained in the (meth)acrylic resin (A) and/or the optionally contained functional group carboxyl group. A compound having two or more groups.
  • the crosslinking agent (C) is not particularly limited, but a compound having two or more functional groups reactive with hydroxyl groups is preferred.
  • a compound having two or more functional groups reactive with the carboxy group may be used.
  • the functional group having reactivity with a hydroxy group include an isocyanato group, an epoxy group, a carboxy group, an acid anhydride group, an aziridinyl group, and from the viewpoint of reactivity, an isocyanato group and an epoxy group are preferable. Particularly preferred is an isocyanato group.
  • the functional group having reactivity with a carboxyl group include an epoxy group, a hydroxy group, and an aziridinyl group. From the viewpoint of reactivity, an epoxy group and an aziridinyl group are preferable.
  • crosslinking agent (C) examples include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hydrogenated tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane- 4,4'-diisocyanate, isophorone diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, isocyanurate of hexamethylene diisocyanate, tetramethylxylylene diisocyanate, 1,5-naphthalene diisocyanate, tolylene diisocyanate of trimethylolpropane Adducts, polyisocyanates such as xylylene diisocyanate adducts of trimethylolpropane, triphenylmethane triisocyanate, methylenebis(4-phenylmethane)triisocyanate; 1,3-bis(N
  • crosslinking agents (C) it is preferable to use at least one selected from the group consisting of polyisocyanates and polyepoxy compounds because of its good reactivity with the (meth)acrylic resin (A). , it is more preferable to use polyisocyanate.
  • the crosslinking agent (C) may be used alone or in combination of two or more.
  • the crosslinking agent (C) is preferably 0.1 to 30 parts by weight, more preferably 0.1 to 20 parts by weight, based on 100 parts by weight of the (meth)acrylic resin (A), and The amount is more preferably .1 to 10 parts by weight, and even more preferably 0.1 to 5 parts by weight.
  • the content of the crosslinking agent (C) is 0.1 parts by mass or more based on 100 parts by mass of the (meth)acrylic resin (A)
  • a three-dimensional crosslinked structure is sufficiently formed in the adhesive composition during UV irradiation. , the adhesive force of the adhesive composition after UV irradiation can be sufficiently reduced.
  • the content of the crosslinking agent (C) is 30 parts by mass or less with respect to 100 parts by mass of the (meth)acrylic resin (A)
  • the adhesive strength of the adhesive composition before UV irradiation is good.
  • other ingredients in the method for producing an adhesive composition, other components than the (meth)acrylic resin (A), the photopolymerization initiator (B), and the crosslinking agent (C) may be mixed as necessary.
  • other components include tackifiers, solvents, and various additives.
  • tackifier As the tackifier, conventionally known tackifiers can be used without particular limitation. Examples of tackifiers include terpene-based tackifier resins, phenolic tackifier resins, rosin-based tackifier resins, aliphatic petroleum resins, aromatic petroleum resins, copolymer petroleum resins, and alicyclic petroleum resins. , xylene resin, epoxy tackifier resin, polyamide tackifier resin, ketone tackifier resin, and elastomer tackifier resin. These tackifiers may be used alone or in combination of two or more.
  • the amount added is preferably 30 parts by mass or less, more preferably 5 to 20 parts by mass, based on 100 parts by mass of the (meth)acrylic resin (A).
  • solvent can be used to dilute the adhesive composition for the purpose of adjusting the viscosity of the adhesive composition.
  • a solvent can be used to adjust the viscosity of the pressure-sensitive adhesive composition to an appropriate viscosity.
  • organic solvents such as methyl ethyl ketone, methyl isobutyl ketone, acetone, ethyl acetate, propyl acetate, tetrahydrofuran, dioxane, cyclohexanone, hexane, toluene, xylene, n-propanol, and isopropyl alcohol can be used.
  • organic solvents such as methyl ethyl ketone, methyl isobutyl ketone, acetone, ethyl acetate, propyl acetate, tetrahydrofuran, dioxane, cyclohexanone, hexane, toluene, xylene, n-propanol, and isopropyl alcohol can be used.
  • solvents may be used alone or in combination of two or more.
  • additives include plasticizers, surface lubricants, leveling agents, softeners, antioxidants, anti-aging agents, light stabilizers, ultraviolet absorbers, polymerization inhibitors, benzotriazole-based light stabilizers, and phosphorus.
  • additives include acid ester and other flame retardants, surfactants, and antistatic agents.
  • the adhesive sheet can be manufactured, for example, by the method shown below.
  • an adhesive solution is prepared by dissolving or dispersing the adhesive composition in a solvent.
  • the adhesive composition may be used as it is as an adhesive solution.
  • an adhesive solution is applied onto the base material, and if it contains a solvent, the solvent is removed by heating and drying to form an adhesive layer. Thereafter, a release sheet is laminated on the adhesive layer, if necessary. Furthermore, a pressure-sensitive adhesive sheet can be obtained by curing the obtained sheet in an oven for a certain period of time to form a crosslinked structure, if necessary.
  • the adhesive sheet can also be manufactured by the method shown below.
  • a pressure-sensitive adhesive solution is applied onto a release sheet, and if it contains a solvent, the solvent is removed by heating and drying to form a pressure-sensitive adhesive layer.
  • a release sheet having an adhesive layer is placed on the base material with the adhesive layer side facing the base material, and the adhesive layer is transferred (transferred) onto the base material.
  • a pressure-sensitive adhesive sheet can be obtained by curing the obtained sheet in an oven for a certain period of time to form a crosslinked structure, if necessary.
  • a base material having an adhesive layer is used as a base material, and the adhesive composition is applied to the adhesive layer, or the adhesive layer and the adhesive layer are laminated so as to face each other, thereby performing dicing.
  • a die bonding integrated film can be obtained.
  • a known method can be used to apply the adhesive solution onto the base material (or onto the release sheet).
  • examples include coating methods using conventional coaters, such as gravure roll coater, reverse roll coater, kiss roll coater, dip roll coater, bar coater, knife coater, spray coater, comma coater, and direct coater. It will be done.
  • Conditions for heating and drying the applied adhesive solution are not particularly limited, but heating and drying is usually carried out at 25 to 180°C, preferably 60 to 150°C, for 1 to 20 minutes, preferably 1 to 10 minutes. . By performing heat drying in the above range, the solvent contained in the adhesive solution can be removed.
  • the conditions for curing the heated and dried sheet in an oven for a certain period of time are not particularly limited, but the curing is usually carried out at 25 to 100°C, preferably 30 to 80°C, for 1 to 30 days, preferably 1 to 14 days.
  • the (meth)acrylic resin (A) can be crosslinked with the crosslinking agent (C), and the gel fraction of the adhesive layer can be adjusted to a desired range.
  • the adhesive sheet can be used as a removable adhesive sheet, for example, when manufacturing electronic components. Specifically, a removable adhesive sheet is used to fix an adherend in each step of manufacturing electronic components, and after subjecting it to various processing steps, irradiates the adherend with UV (ultraviolet light). Used for peeling from. Therefore, the adhesive sheet can be used as a backgrind tape, dicing tape, etc. when processing semiconductor wafers.
  • the adhesive sheet can also be used as a support tape for fragile members such as ultra-thin glass substrates and easily warped members such as FPC boards.
  • the adhesive sheet has excellent adhesion to the adhesive layer and excellent releasability after UV irradiation, and is therefore suitable for a dicing tape used when manufacturing a dicing/die bonding integrated film.
  • the adhesive sheet When using an adhesive sheet as a dicing tape for a wafer, the adhesive sheet is attached to the wafer on which multiple parts are formed before performing the dicing process. Next, the wafer is cut and diced into individual parts to form small element pieces (chips). Thereafter, UV irradiation is applied to the adhesive sheet pasted on each element piece. As a result, the adhesive layer is irradiated with UV light through the base material of the adhesive sheet, and the unsaturated bonds in the adhesive form a three-dimensional crosslinked structure and are cured. As a result, the adhesive force of the adhesive layer decreases. Thereafter, the adhesive sheet is peeled off from above each element piece.
  • Examples of light sources used when performing UV irradiation include high-pressure mercury lamps, ultra-high-pressure mercury lamps, carbon arc lamps, xenon lamps, metal halide lamps, chemical lamps, and black lights.
  • the amount of UV irradiation applied to the adhesive sheet is preferably 50 to 3,000 mJ/cm 2 , more preferably 100 to 600 mJ/cm 2 .
  • the adhesive layer can be cured at a sufficiently fast curing speed by UV irradiation, so the adhesive strength of the adhesive layer after UV irradiation is can be made sufficiently small.
  • (meth)acrylic resins (A) and (cA) are shown below.
  • Hydroxy group-containing (meth)acrylate (m-1) 2-Hydroxyethyl acrylate, Nippon Shokubai Co., Ltd. 2-Hydroxyethyl methacrylate, Nippon Shokubai Co., Ltd. 4-Hydroxybutyl acrylate, Osaka Organic Chemical Industry Co., Ltd.
  • RAFT agent 2- “(dodecylsulfanylthiocarbonyl)sulfanyl” propanoic acid, Fujifilm Wako Pure Chemical Industries, Ltd. Bis ⁇ 4-[ethyl-(2-hydroxyethyl)carbamoyl]benzyl ⁇ trithiocarbonate, Fujifilm Wako Pure Chemical Industries, Ltd. S,S-dibenzyltrithiocarbonate, Fujifilm Wako Pure Chemical Industries, Ltd. 2-phenyl-2-propyldithiobenzoic acid, Ouchi Shinko Chemical Co., Ltd. additive: Ethyl 2-methyl-2-n-butylterranyl-propionate, Otsuka Chemical Co., Ltd.
  • Isocyanato group-containing ethylenically unsaturated compound (a): Karenz (trademark) MOI, 2-isocyanatoethyl methacrylate, Showa Denko K.K. AOI-VM (trademark), 2-isocyanatoethyl acrylate, Showa Denko K.K.
  • (meth)acrylic resins (A) and (cA) Synthesis examples of (meth)acrylic resins (A) and (cA) are shown below.
  • the weight average molecular weight, molecular weight distribution, acid value, and glass transition temperature of the (meth)acrylic resins (A) and (cA) were measured and calculated using the methods described above.
  • the ethylenically unsaturated group equivalents of the (meth)acrylic resins (A) and (cA) were calculated from the charged amounts as described above.
  • the hydroxyl value is the mass (mg) of potassium hydroxide required to neutralize acetic acid bonded to hydroxyl groups when 1 g of resin is acetylated, according to JIS K 0070:1992.
  • Table 1 shows the weight average molecular weight, molecular weight distribution, ethylenically unsaturated group equivalent, hydroxyl value, acid value, and glass transition temperature of the (meth)acrylic resins (A) and (c
  • the temperature of the reactant was lowered to 60°C, and a mixed solution of 16.5 parts by mass (10.6 mol) of 2-isocyanatoethyl methacrylate and 0.18 parts by mass of dibutyltin dilaurate, which is a urethanization catalyst, was added through the dropping funnel. dripped. After the dropwise addition was completed, the reaction system was maintained at 70° C. for 4 hours to eliminate the isocyanate groups.
  • Synthesis Example 1 was carried out in the same manner as in Synthesis Example 1, except that ethyl 2-methyl-2-n-butylterranyl-propionate was used instead of 2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propanoic acid and the composition shown in Table 1 was used.
  • a (meth)acrylic resin (cA2) was obtained.
  • TETRAD-X N,N'-[1,3-phenylenebis(methylene)]bis[bis(oxiran-2-ylmethyl)amine] (manufactured by Mitsubishi Gas Chemical Co., Ltd., product name: TETRAD-X)
  • the (meth)acrylic resin (A) or (cA) shown in Table 2, the photopolymerization initiator (B), and the crosslinking agent (C) shown in Table 2 were placed in a plastic container in a room blocked from active rays. The indicated content (parts by mass) was added and stirred to obtain adhesive compositions (B1) to (B4) and (cB1) to (cB3).
  • the numerical values of (meth)acrylic resins (A1) to (A4) and (meth)acrylic resins (cA1) to (cA3) in Table 2 are based on the solid content of the solutions used, that is, (meth)acrylic resins (A1) to ( A4) and the amounts used (parts by mass) of (cA1) to (cA3).
  • the numerical value of the photopolymerization initiator (B) is the amount (parts by mass) of the photopolymerization initiator (B) used per 100 parts by mass of the (meth)acrylic resin (A) or (cA).
  • the numerical value of the crosslinking agent (C) is the amount (parts by mass) of the crosslinking agent (C) used per 100 parts by mass of the (meth)acrylic resin (A) or (cA).
  • Example 2-1 Preparation of adhesive sheet A silicone-based light release PET film (Toyobo Co., Ltd., product name: E7006, thickness 25 ⁇ m) was prepared as a separator, and the release-treated surface was The adhesive composition (B1) was applied using an applicator so that the thickness after curing was 20 ⁇ m, and the adhesive composition was dried by heating at 100° C. for 2 minutes to form an adhesive layer. Next, a 90 ⁇ m thick PO film was prepared as a sheet-like base material. The PO film was attached to the adhesive layer using a rubber roller so that the corona-treated surface of the PO film adhered to the exposed surface of the adhesive layer. The pressure-sensitive adhesive sheet of Example 2-1 was obtained by curing in an oven at 40° C. for 3 days to crosslink and cure the pressure-sensitive adhesive layer.
  • Example 2-2 to 2-4 and Comparative Examples 2-1 to 2-3 Production of adhesive sheets Except for using the adhesive composition shown in Table 2 instead of the adhesive composition (B1) Adhesive sheets of Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-3 were obtained in the same manner as in Example 2-1.
  • the measurement conditions were a peel angle of 30° and a tensile speed of 600 mm/min.
  • the storage of the samples and the measurement of peel strength were performed under an environment of a temperature of 23° C. and a relative humidity of 40%. Table 2 shows the results.
  • the silicon wafer after stealth dicing was polished to a thickness of 30 ⁇ m.
  • a grinder polisher device (DGP8761, DISCO Co., Ltd.) was used for polishing.
  • An adhesive layer of a dicing/die bonding integrated film was attached to the polished silicon wafer under the following conditions with the base side surface of the dicing tape facing the dicing ring. Thereafter, the BG tape was peeled off from the surface of the silicon wafer.
  • ⁇ Pasting conditions> ⁇ Packing device: DFM2800 (Disco Co., Ltd.) ⁇ Application temperature: 70°C ⁇ Application speed: 10mm/s ⁇ Application tension level: Level 6
  • the silicon wafer and the adhesive layer were diced into a plurality of chips with adhesive chips (size: 10 mm x 10 mm).
  • ⁇ Cooling expansion conditions > ⁇ Cooling temperature: -15°C ⁇ Cooling time: 120 seconds ⁇ Push-up amount: 12mm ⁇ Push-up speed: 200mm/sec ⁇ Holding time after push-up: 3 seconds ⁇ Heat shrink conditions> ⁇ Heater temperature: 220°C ⁇ Heater rotation speed: 5°/sec ⁇ Listing amount: 8mm ⁇ Tape cooling waiting time: 10 seconds
  • the adhesive layer was irradiated with ultraviolet rays from the surface of the adhesive sheet on the base material side under the following conditions. This cured the adhesive layer and reduced the adhesive force to the adhesive layer.
  • DAF jump Evaluation of processability (DAF jump) After cooling expansion and heat shrinking, DAF jump was evaluated according to the following criteria. Table 2 shows the results. A: DAF jump did not occur at all. B: DAF did not fly, but peeling or lifting was observed at the interface between the adhesive layer and the pressure-sensitive adhesive layer. C: DAF skipping occurred in at least one location.
  • the interval (kerf width) between the chips with adhesive chips after singulation was measured using a microscope.
  • the kerf width in the MD/TD direction was measured at two locations each on the outer periphery (top, bottom, left and right) of the silicon wafer and at one location in the center (total of 18 points), and the average value was determined. Evaluation was made based on the following criteria. Table 2 shows the results.
  • A The average value of the kerf width was 70 ⁇ m or more and less than 100 ⁇ m.
  • B The average value of the kerf width was 50 ⁇ m or more and less than 70 ⁇ m.
  • Kerf width is one of the important items in the stealth dicing process from the viewpoint of achieving excellent pick-up properties.
  • chip edge peeling occurred after cooling expansion and heat shrinking, and pickup failure also occurred.
  • Comparative Example 2-2 which used a (meth)acrylic resin obtained from a copolymer produced by organic tellurium radical polymerization, had a small amount of low molecular weight components and insufficient propagation of breaking stress, resulting in adhesive layer separation.
  • the gender was D.
  • a (meth)acrylic resin suitable for an adhesive composition is provided.
  • a pressure-sensitive adhesive layer formed from a pressure-sensitive adhesive composition produced using a (meth)acrylic resin can be preferably used as a pressure-sensitive adhesive layer of a removable pressure-sensitive adhesive sheet, particularly a dicing/die-bonding integrated film.

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Abstract

A method for producing a (meth)acrylic resin having an ethylenically unsaturated group comprising a step (i) that reversible addition-fragmentation chain transfer (RAFT) polymerizes a raw material monomer group (M) containing a hydroxy group-containing (meth)acrylate (m-1) and an alkyl (meth)acrylate (m-2) to obtain a copolymer (A-0) and a step (ii) that adds an isocyanate group-containing ethylenically unsaturated compound (a) to some of the side chain hydroxy groups of the copolymer (A-0) to obtain a (meth)acrylic resin.

Description

（メタ）アクリル樹脂の製造方法及び粘着剤組成物の製造方法Method for producing (meth)acrylic resin and method for producing adhesive composition
　本開示の内容は、粘着剤組成物に用いる（メタ）アクリル樹脂の製造方法、及び粘着剤組成物の製造方法に関する。 The content of the present disclosure relates to a method for producing a (meth)acrylic resin used in a pressure-sensitive adhesive composition and a method for producing a pressure-sensitive adhesive composition.
　従来、半導体の製造工程などにおいて、様々な粘着シートが用いられている。具体的には、半導体ウェハの裏面研削（バックグラインド）工程においてウェハを保護するための保護シート（バックグラインドテープ）、半導体ウェハから素子小片への切断分割（ダイシング）工程において用いられる固定用シート（ダイシングテープ）などがある。これらの粘着シートは、被着体である半導体ウェハに貼付され、所定の加工工程が終了した後に被着体から剥離される再剥離型の粘着シートである。 Conventionally, various adhesive sheets have been used in semiconductor manufacturing processes and the like. Specifically, we use protective sheets (backgrind tape) to protect wafers during the backgrinding process of semiconductor wafers, and fixing sheets ( dicing tape), etc. These adhesive sheets are removable adhesive sheets that are attached to a semiconductor wafer as an adherend and peeled off from the adherend after a predetermined processing step is completed.
　再剥離型の粘着シートの粘着剤層に用いられる粘着剤組成物としては、（メタ）アクリル樹脂の側鎖にＵＶ（紫外線）硬化が可能なエチレン性不飽和基を導入した樹脂を含むものが知られている。このような粘着剤組成物は、ＵＶ照射により架橋反応を起こして硬化し、粘着力が低下する。例えば、特許文献１（特開２０１８－１３８６８２号公報）には、分子量分布（Ｍｗ／Ｍｎ）１．０５～２．５のリビングラジカル重合ポリマー、特に、有機テルル重合開始剤を用いたリビングラジカル重合により得られたポリマーの側鎖に紫外線硬化が可能な重合性基を導入した（メタ）アクリルポリマーを含有する粘着テープが記載されている。 Adhesive compositions used in the adhesive layer of removable adhesive sheets include those containing resins in which UV (ultraviolet rays) curable ethylenically unsaturated groups are introduced into the side chains of (meth)acrylic resins. Are known. Such an adhesive composition undergoes a crosslinking reaction and is cured by UV irradiation, resulting in a decrease in adhesive strength. For example, Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2018-138682) describes a living radical polymerization polymer having a molecular weight distribution (Mw/Mn) of 1.05 to 2.5, particularly a living radical polymerization polymer using an organic tellurium polymerization initiator. An adhesive tape containing a (meth)acrylic polymer in which a polymerizable group that can be cured by ultraviolet rays is introduced into the side chain of the polymer obtained by the method is described.
特開２０１８－１３８６８２号公報Japanese Patent Application Publication No. 2018-138682
　半導体製造工程の短縮のため、再剥離型粘着シートであるダイシングテープとダイボンド（接着剤層）が一体となったフィルムであるダイシング・ダイボンド一体型フィルムが用いられる。このフィルムは、例えば、接着剤層を半導体ウェハの裏面に貼付し、ダイシングテープに由来する粘着剤層をダイシングリングに貼付することにより用いられる。その後、半導体ウェハをダイシングブレードによりダイシングして、個片化された半導体チップを得る。したがって、ダイシングテープに由来する粘着剤層は、ダイシング工程において接着剤層及びダイシングリングに対する高い粘着力が求められる一方、半導体チップのピックアップ工程では、各半導体チップへの粘着剤の残り（糊残り）がなく、接着剤片付きの半導体チップを容易にピックアップできることが求められる。粘着剤層の接着剤層に対する粘着力が不十分であると、ダイシングブレードの高速回転によって接着剤層と粘着剤層の間で剥離が生じるとともに接着剤層が破断し、接着剤層の切れ端が飛散する現象（ＤＡＦ（Ｄｉｅ　ａｔｔａｃｈ　ｆｉｌｍ）飛び）が生じる。粘着剤層のダイシングリングに対する粘着力が不十分であると、切削水の水流によってダイシングリングが粘着剤層から剥離する現象（リング剥がれ）が生じる。 In order to shorten the semiconductor manufacturing process, a dicing/die bond integrated film is used, which is a film in which a dicing tape, which is a removable adhesive sheet, and a die bond (adhesive layer) are integrated. This film is used, for example, by attaching an adhesive layer to the back surface of a semiconductor wafer and attaching an adhesive layer derived from a dicing tape to a dicing ring. Thereafter, the semiconductor wafer is diced using a dicing blade to obtain individualized semiconductor chips. Therefore, the adhesive layer derived from the dicing tape is required to have high adhesion to the adhesive layer and the dicing ring in the dicing process, but in the semiconductor chip pickup process, adhesive residue (adhesive residue) is left on each semiconductor chip. It is required to be able to easily pick up semiconductor chips with adhesive pieces. If the adhesion of the adhesive layer to the adhesive layer is insufficient, the high-speed rotation of the dicing blade will cause peeling between the adhesive layers and break the adhesive layer, resulting in broken edges of the adhesive layer. A scattering phenomenon (DAF (Die Attach Film) flying) occurs. If the adhesive force of the adhesive layer to the dicing ring is insufficient, a phenomenon in which the dicing ring peels off from the adhesive layer (ring peeling) occurs due to the flow of cutting water.
　近年、ダイシングブレードを用いないダイシング方法として、ステルスダイシングが注目されている。ステルスダイシングでは、レーザ光をウェハ内部に集光させて、分割するための起点（改質層）を形成し、ウェハの裏面に再剥離型粘着シートを貼付し、このシートを冷却エキスパンドすることによって、個片化された半導体チップを得る。ステルスダイシングにおいてダイシング・ダイボンド一体型フィルムを用いる場合、冷却エキスパンドによってウェハ及び接着剤層が個片化される。冷却エキスパンド工程においても粘着剤層の粘着力が不十分であると、エキスパンド時の衝撃及び応力により、接着剤層の外周部が破断し、切れ端が飛散する現象（ＤＡＦ飛び）が生じたり、接着剤片付きチップの端部と粘着剤層との剥離（チップエッジ剥離）が生じ、その後の工程に不具合が発生する場合がある。 In recent years, stealth dicing has been attracting attention as a dicing method that does not use a dicing blade. In stealth dicing, a laser beam is focused inside the wafer to form a starting point (modified layer) for dividing the wafer, a removable adhesive sheet is attached to the back of the wafer, and this sheet is cooled and expanded. , obtain singulated semiconductor chips. When using a dicing/die-bonding integrated film in stealth dicing, the wafer and adhesive layer are separated into pieces by cooling expansion. If the adhesive strength of the adhesive layer is insufficient even during the cooling expansion process, the outer periphery of the adhesive layer may break due to the impact and stress during expansion, causing the phenomenon of scattering of pieces (DAF flying) or the adhesion. Peeling between the edge of the chip with the adhesive and the adhesive layer (chip edge peeling) may occur, causing problems in subsequent steps.
　このように、ダイシング・ダイボンド一体型フィルムに用いられる粘着剤層には、接着剤層に対する高い粘着力を有し、ＵＶ照射後には糊残りなく接着剤層から容易に剥離できるという、他の再剥離型粘着シートでは要求されない特性が求められる。したがって、従来再剥離型粘着シートに用いられているアクリル系粘着剤をダイシング・ダイボンド一体型フィルムにそのまま適用することは困難である。 In this way, the adhesive layer used in the dicing/die-bonding integrated film has high adhesion to the adhesive layer and can be easily peeled off from the adhesive layer without leaving any adhesive residue after UV irradiation. Characteristics that are not required for releasable pressure-sensitive adhesive sheets are required. Therefore, it is difficult to apply the acrylic pressure-sensitive adhesive conventionally used in removable pressure-sensitive adhesive sheets to a dicing/die-bonding integrated film as is.
　本開示は、接着剤層に対して十分な粘着力を有し、かつ、ＵＶ照射した後に粘着シートを接着剤層から剥離する際には、優れた剥離性が得られるとともに、糊残りが発生しにくい粘着剤層を提供することができる（メタ）アクリル樹脂又は（メタ）アクリル樹脂を含む粘着剤組成物を得ることができる製造方法を提供する。 The present disclosure has sufficient adhesion to the adhesive layer, and when the adhesive sheet is peeled off from the adhesive layer after UV irradiation, excellent peelability is obtained and no adhesive remains. Provided is a manufacturing method capable of obtaining a (meth)acrylic resin or a pressure-sensitive adhesive composition containing a (meth)acrylic resin that can provide a pressure-sensitive adhesive layer that is difficult to peel.
　本発明者らは、ヒドロキシ基含有（メタ）アクリレート、及びアルキル（メタ）アクリレートを可逆的付加開裂連鎖移動（ＲＡＦＴ）重合することにより得られた共重合体をイソシアナト基含有エチレン性不飽和化合物により変性したポリマーが、ダイシング・ダイボンド一体型フィルムの粘着剤層に好適に用いられることを見出した。 The present inventors used a copolymer obtained by reversible addition fragmentation chain transfer (RAFT) polymerization of a hydroxy group-containing (meth)acrylate and an alkyl (meth)acrylate with an isocyanato group-containing ethylenically unsaturated compound. It has been found that a modified polymer can be suitably used in the adhesive layer of a dicing/die-bonding integrated film.
　すなわち、本開示は次の態様を含む。
［１］
　ヒドロキシ基含有（メタ）アクリレート（ｍ－１）、及びアルキル（メタ）アクリレート（ｍ－２）を含有する原料モノマー群（Ｍ）を可逆的付加開裂連鎖移動（ＲＡＦＴ）重合して、共重合体（Ａ－０）を得る工程（ｉ）と、
　前記共重合体（Ａ－０）が有する側鎖ヒドロキシ基の一部にイソシアナト基含有エチレン性不飽和化合物（ａ）を付加して、エチレン性不飽和基を有する（メタ）アクリル樹脂（Ａ）を得る工程（ｉｉ）と、
を含む（メタ）アクリル樹脂の製造方法。
［２］
　前記原料モノマー群（Ｍ）が、カルボキシ基含有単量体（ｍ－３）をさらに含有する［１］に記載の（メタ）アクリル樹脂の製造方法。
［３］
　前記エチレン性不飽和基を有する（メタ）アクリル樹脂（Ａ）の分子量分布（Ｍｗ／Ｍｎ）が２．４～１０．０である［１］又は［２］に記載の（メタ）アクリル樹脂の製造方法。
［４］
　［１］～［３］のいずれかに記載の製造方法により得られる、エチレン性不飽和基を有する（メタ）アクリル樹脂（Ａ）と、光重合開始剤（Ｂ）と、架橋剤（Ｃ）とを混合する工程（ｉｉｉ）を含む粘着剤組成物の製造方法。
［５］
　前記架橋剤（Ｃ）が、ポリイソシアネート、及びポリエポキシ化合物からなる群から選択される少なくとも一種である［４］に記載の粘着剤組成物の製造方法。
［６］
　［４］又は［５］に記載の製造方法により得られる粘着剤組成物に架橋構造を形成させる工程を含む粘着剤層の製造方法。
［７］
　［４］又は［５］に記載の製造方法により得られる粘着剤組成物をシート状の基材に塗布して粘着剤層を作製することを含む粘着シートの製造方法。
［８］
　［７］に記載の製造方法により得られる粘着剤層に架橋構造を形成させる工程を含む粘着シートの製造方法。
［９］
　［８］に記載の製造方法により得られる、架橋構造を形成された粘着剤層に接着剤層を積層することを含むダイシング・ダイボンディング一体型フィルムの製造方法。
［１０］
　［４］又は［５］に記載の製造方法により得られる粘着剤組成物を接着剤層に塗布することを含むダイシング・ダイボンディング一体型フィルムの製造方法。 That is, the present disclosure includes the following aspects.
[1]
A copolymer is obtained by polymerizing a raw material monomer group (M) containing a hydroxy group-containing (meth)acrylate (m-1) and an alkyl (meth)acrylate (m-2) by reversible addition-fragmentation chain transfer (RAFT). Step (i) of obtaining (A-0);
An isocyanato group-containing ethylenically unsaturated compound (a) is added to a part of the side chain hydroxyl groups of the copolymer (A-0) to produce a (meth)acrylic resin (A) having an ethylenically unsaturated group. Step (ii) of obtaining
A method for producing a (meth)acrylic resin containing.
[2]
The method for producing a (meth)acrylic resin according to [1], wherein the raw material monomer group (M) further contains a carboxy group-containing monomer (m-3).
[3]
The (meth)acrylic resin according to [1] or [2], wherein the (meth)acrylic resin (A) having an ethylenically unsaturated group has a molecular weight distribution (Mw/Mn) of 2.4 to 10.0. Production method.
[4]
A (meth)acrylic resin (A) having an ethylenically unsaturated group obtained by the production method according to any one of [1] to [3], a photopolymerization initiator (B), and a crosslinking agent (C) A method for producing an adhesive composition, comprising the step (iii) of mixing.
[5]
The method for producing an adhesive composition according to [4], wherein the crosslinking agent (C) is at least one selected from the group consisting of polyisocyanates and polyepoxy compounds.
[6]
[4] or [5] A method for producing an adhesive layer, comprising a step of forming a crosslinked structure in the adhesive composition obtained by the production method according to [5].
[7]
A method for producing a pressure-sensitive adhesive sheet, comprising applying the pressure-sensitive adhesive composition obtained by the production method according to [4] or [5] to a sheet-like base material to prepare a pressure-sensitive adhesive layer.
[8]
A method for producing a pressure-sensitive adhesive sheet, comprising a step of forming a crosslinked structure in the pressure-sensitive adhesive layer obtained by the method according to [7].
[9]
A method for producing a dicing/die bonding integrated film obtained by the production method according to [8], which includes laminating an adhesive layer on an adhesive layer formed with a crosslinked structure.
[10]
[4] or [5] A method for producing an integrated dicing and die bonding film, the method comprising applying the pressure-sensitive adhesive composition obtained by the production method according to [5] to an adhesive layer.
　本開示の方法により得られた（メタ）アクリル樹脂をダイシング・ダイボンド一体型フィルムの粘着剤層に用いることにより、接着剤層に対して十分な粘着力を有し、かつ、ＵＶ照射した後に粘着シートを接着剤層から剥離する際には、優れた剥離性が得られるとともに、糊残りが発生しにくい粘着剤層を提供することができる。 By using the (meth)acrylic resin obtained by the method of the present disclosure in the adhesive layer of the dicing/die-bonding integrated film, it has sufficient adhesion to the adhesive layer and is sticky after UV irradiation. When the sheet is peeled off from the adhesive layer, it is possible to obtain an adhesive layer that exhibits excellent peelability and is less likely to leave adhesive residue.
　以下、本発明の実施形態について詳細に説明する。ただし、本発明は、以下に示す実施形態に限定されるものではない。 Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments shown below.
　本明細書では、数値範囲について「～」を使用する場合には、両端の数値は、それぞれ上限値及び下限値であり、数値範囲に含まれる。 In this specification, when "~" is used for a numerical range, the numerical values at both ends are the upper limit and lower limit, respectively, and are included in the numerical range.
　本明細書において、「（メタ）アクリル」は、メタクリル又はアクリルを意味し、「（メタ）アクリレート」は、アクリレート又はメタクリレートを意味し、「（メタ）アクリロイルオキシ」はアクリロイルオキシ又はメタクリロイルオキシを意味する。 As used herein, "(meth)acrylic" means methacrylic or acrylic, "(meth)acrylate" means acrylate or methacrylate, and "(meth)acryloyloxy" means acryloyloxy or methacryloyloxy. do.
　本明細書において「重量平均分子量」及び「数平均分子量」は、ゲルパーミエーションクロマトグラフィー（ＧＰＣ：ｇｅｌ　ｐｅｒｍｅａｔｉｏｎ　ｃｈｒｏｍａｔｏｇｒａｐｈｙ）を用いて下記条件にて常温（２３℃）で測定し、標準ポリスチレン検量線を用いて求めた値とする。
　装置：Ｓｈｏｄｅｘ（商標）　ＧＰＣ－１０１（昭和電工株式会社）
　カラム：Ｓｈｏｄｅｘ（商標）　ＬＦ－８０４（昭和電工株式会社）
　カラム温度：４０℃
　試料：試料の０．２質量％テトラヒドロフラン溶液
　流量：１ｍＬ／分
　溶離液：テトラヒドロフラン
　検出器：Ｓｈｏｄｅｘ（商標）　ＲＩ－７１Ｓ（昭和電工株式会社） In this specification, "weight average molecular weight" and "number average molecular weight" are measured at room temperature (23°C) using gel permeation chromatography (GPC) under the following conditions, and a standard polystyrene calibration curve is used. The value obtained using
Equipment: Shodex (trademark) GPC-101 (Showa Denko K.K.)
Column: Shodex (trademark) LF-804 (Showa Denko K.K.)
Column temperature: 40℃
Sample: 0.2% by mass solution of sample in tetrahydrofuran Flow rate: 1 mL/min Eluent: Tetrahydrofuran Detector: Shodex (trademark) RI-71S (Showa Denko K.K.)
　本明細書において「ガラス転移温度（Ｔｇ）」は、１０ｍｇの試料を採取し、示差走査熱量計（ＤＳＣ）を用いて、１０℃／分の昇温速度で－１００℃から２００℃まで試料の温度を変化させて示差走査熱量測定を行い、観察されたガラス転移による吸熱開始温度である。吸熱開始温度が２つ以上観察された場合は、Ｔｇは２つ以上の吸熱開始温度の単純平均値である。 In this specification, "glass transition temperature (Tg)" refers to the temperature of a sample taken from -100°C to 200°C at a heating rate of 10°C/min using a differential scanning calorimeter (DSC). Differential scanning calorimetry was performed while changing the temperature, and this is the observed temperature at which endotherm begins due to glass transition. If two or more endothermic onset temperatures are observed, Tg is the simple average value of the two or more endothermic onset temperatures.
［エチレン性不飽和基を有する（メタ）アクリル樹脂（Ａ）の製造方法］
　エチレン性不飽和基を有する（メタ）アクリル樹脂（Ａ）（以下、単に「（メタ）アクリル樹脂（Ａ）」という）の製造方法は、ヒドロキシ基含有（メタ）アクリレート（ｍ－１）、及びアルキル（メタ）アクリレート（ｍ－２）を含有する原料モノマー群（Ｍ）を可逆的付加開裂連鎖移動（ＲＡＦＴ：Ｒｅｖｅｒｓｉｂｌｅ　Ａｄｄｉｔｉｏｎ－Ｆｒａｇｍｅｎｔａｔｉｏｎ　ｃｈａｉｎ　Ｔｒａｎｓｆｅｒ）重合して、共重合体（Ａ－０）を得る工程（ｉ）と、共重合体（Ａ－０）が有する側鎖ヒドロキシ基の一部にイソシアナト基含有エチレン性不飽和化合物（ａ）を付加して（メタ）アクリル樹脂（Ａ）を得る工程（ｉｉ）と、を含む。原料モノマー群（Ｍ）は、カルボキシ基含有単量体（ｍ－３）を含有してもよい。 [Method for producing (meth)acrylic resin (A) having ethylenically unsaturated group]
A method for producing a (meth)acrylic resin (A) having an ethylenically unsaturated group (hereinafter simply referred to as "(meth)acrylic resin (A)") includes hydroxyl group-containing (meth)acrylate (m-1), and A copolymer (A-0) is obtained by subjecting a raw material monomer group (M) containing an alkyl (meth)acrylate (m-2) to reversible addition-fragmentation chain transfer (RAFT) polymerization. Step (i) and a step of adding an isocyanato group-containing ethylenically unsaturated compound (a) to a part of the side chain hydroxy groups of the copolymer (A-0) to obtain a (meth)acrylic resin (A) (ii). The raw material monomer group (M) may contain a carboxy group-containing monomer (m-3).
＜工程（ｉ）＞
　共重合体（Ａ－０）は、可逆的付加開裂連鎖移動剤（ＲＡＦＴ剤）の存在下、ヒドロキシ基含有（メタ）アクリレート（ｍ－１）、及びアルキル（メタ）アクリレート（ｍ－２）、並びに任意選択的にカルボキシ基含有単量体（ｍ－３）を含有する原料モノマー群（Ｍ）をＲＡＦＴ重合することにより得られる。本明細書において、ＲＡＦＴ重合とは、ＲＡＦＴ剤の存在下で行われるラジカル重合を意味する。ＲＡＦＴ重合は、リビングラジカル重合の一種である。リビングラジカル重合は、分子量分布の小さいポリマーを得ることのできる重合方法として一般的に知られており、その具体例として、原子移動ラジカル重合、有機テルル介在ラジカル重合、ＲＡＦＴ重合等が挙げられる。これらのうち、ＲＡＦＴ重合は、ハロゲン及び重金属を使用しないため、環境負荷が低く、半導体用途に好適である。いかなる理論に拘束される訳ではないが、ＲＡＦＴ重合により得られた共重合体（Ａ－０）は、他のリビングラジカル重合により得られる（メタ）アクリル共重合体に比べて分子量分布が適切であるため、共重合体（Ａ－０）から得られた（メタ）アクリル樹脂（Ａ）を用いて製造された粘着剤組成物は、接着剤層に対する濡れ性に優れ、接着剤層に対する高い密着力を有する。これは、粘着剤組成物の濡れ性、及び流動性に（メタ）アクリル樹脂（Ａ）の低分子量成分が寄与しているためである。（メタ）アクリル共重合体の分子量分布が狭すぎる場合、得られる粘着剤組成物の流動性及び接着剤層に対する濡れ性は低く、十分な密着力が得られない。 <Step (i)>
The copolymer (A-0) is prepared by combining a hydroxy group-containing (meth)acrylate (m-1) and an alkyl (meth)acrylate (m-2) in the presence of a reversible addition-fragmentation chain transfer agent (RAFT agent), It can also be obtained by RAFT polymerizing a raw material monomer group (M) optionally containing a carboxy group-containing monomer (m-3). As used herein, RAFT polymerization refers to radical polymerization performed in the presence of a RAFT agent. RAFT polymerization is a type of living radical polymerization. Living radical polymerization is generally known as a polymerization method capable of obtaining a polymer with a small molecular weight distribution, and specific examples thereof include atom transfer radical polymerization, organic tellurium-mediated radical polymerization, RAFT polymerization, and the like. Among these, RAFT polymerization does not use halogens or heavy metals, so it has a low environmental impact and is suitable for semiconductor applications. Although not bound by any theory, the copolymer (A-0) obtained by RAFT polymerization has a more appropriate molecular weight distribution than (meth)acrylic copolymers obtained by other living radical polymerizations. Therefore, the adhesive composition produced using the (meth)acrylic resin (A) obtained from the copolymer (A-0) has excellent wettability to the adhesive layer and high adhesion to the adhesive layer. have power. This is because the low molecular weight component of the (meth)acrylic resin (A) contributes to the wettability and fluidity of the adhesive composition. If the molecular weight distribution of the (meth)acrylic copolymer is too narrow, the resulting pressure-sensitive adhesive composition will have low fluidity and wettability with respect to the adhesive layer, and sufficient adhesion will not be obtained.
　重合方法として、溶液重合法、乳化重合法、塊状重合法、懸濁重合法、交互共重合法などを用いることができる。これらの重合方法の中でも、工程（ｉｉ）の付加反応を考慮すると、反応の容易さの点で溶液重合法を用いることが好ましい。 As the polymerization method, a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, a suspension polymerization method, an alternating copolymerization method, etc. can be used. Among these polymerization methods, in consideration of the addition reaction in step (ii), it is preferable to use the solution polymerization method in terms of ease of reaction.
（ヒドロキシ基含有（メタ）アクリレート（ｍ－１））
　ヒドロキシ基含有（メタ）アクリレート（ｍ－１）は、ヒドロキシ基と（メタ）アクリロイルオキシ基を有していれば、特に限定されない。具体的には、２－ヒドロキシエチル（メタ）アクリレート、３－ヒドロキシプロピル（メタ）アクリレート、２－ヒドロキシブチル（メタ）アクリレート、２，３－ジヒドロキシプロピル（メタ）アクリレート、４－ヒドロキシブチル（メタ）アクリレート等のヒドロキシアルキル（メタ）アクリレート；ヒドロキシフェニル（メタ）アクリレート、２－ヒドロキシ－３－フェノキシプロピル（メタ）アクリレート等の芳香環及びヒドロキシ基を有する（メタ）アクリレートなどが挙げられる。中でも、ＵＶ照射後の粘着シートの剥離性の観点から、ヒドロキシアルキル（メタ）アクリレートが好ましく、ヒドロキシアルキル基の炭素原子数が１～６のヒドロキシアルキル（メタ）アクリレートがより好ましく、２－ヒドロキシエチル（メタ）アクリレート、３－ヒドロキシプロピル（メタ）アクリレート、及び４－ヒドロキシブチル（メタ）アクリレートがさらに好ましい。 (Hydroxy group-containing (meth)acrylate (m-1))
The hydroxy group-containing (meth)acrylate (m-1) is not particularly limited as long as it has a hydroxy group and a (meth)acryloyloxy group. Specifically, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate Examples include hydroxyalkyl (meth)acrylates such as acrylate; (meth)acrylates having an aromatic ring and a hydroxyl group such as hydroxyphenyl (meth)acrylate and 2-hydroxy-3-phenoxypropyl (meth)acrylate; Among these, from the viewpoint of peelability of the adhesive sheet after UV irradiation, hydroxyalkyl (meth)acrylates are preferred, hydroxyalkyl (meth)acrylates in which the hydroxyalkyl group has 1 to 6 carbon atoms are more preferred, and 2-hydroxyethyl More preferred are (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate.
　ヒドロキシ基含有（メタ）アクリレート（ｍ－１）の含有量は、原料モノマー群（Ｍ）１００モル％に対して、好ましくは５～５０モル％であり、より好ましくは１０～４０モル％であり、さらに好ましくは１５～３５モル％である。ヒドロキシ基含有（メタ）アクリレート（ｍ－１）の含有量が５モル％以上であると、（メタ）アクリル樹脂（Ａ）が十分なヒドロキシ基を有し、架橋剤（Ｃ）との架橋量を確保できるため、十分な凝集力を有する粘着剤層を得ることができる。加えて、エチレン性不飽和基を導入するための反応点も確保することができ、ＵＶ照射後に粘着シートを被着体から剥離する際のより優れた剥離性を得ることができる。一方、ヒドロキシ基含有（メタ）アクリレート（ｍ－１）の含有量が５０モル％以下であると、粘着剤組成物中での意図しない反応の進行を抑制することができ、保存安定性が良好である。 The content of the hydroxy group-containing (meth)acrylate (m-1) is preferably 5 to 50 mol%, more preferably 10 to 40 mol%, based on 100 mol% of the raw material monomer group (M). , more preferably 15 to 35 mol%. When the content of the hydroxy group-containing (meth)acrylate (m-1) is 5 mol% or more, the (meth)acrylic resin (A) has sufficient hydroxy groups and the amount of crosslinking with the crosslinking agent (C) is Therefore, it is possible to obtain an adhesive layer having sufficient cohesive force. In addition, reaction points for introducing ethylenically unsaturated groups can be secured, and better peelability can be obtained when the pressure-sensitive adhesive sheet is peeled off from the adherend after UV irradiation. On the other hand, when the content of the hydroxy group-containing (meth)acrylate (m-1) is 50 mol% or less, unintended progress of reaction in the adhesive composition can be suppressed, resulting in good storage stability. It is.
（アルキル（メタ）アクリレート（ｍ－２））
　アルキル（メタ）アクリレート（ｍ－２）は、ヒドロキシ基とカルボキシ基を有さず、アルキル基と（メタ）アクリロイルオキシ基を有していれば特に限定されない。具体的には、メチル（メタ）アクリレート、エチル（メタ）アクリレート、ｎ－プロピル（メタ）アクリレート、イソプロピル（メタ）アクリレート、ｎ－ブチル（メタ）アクリレート、ｔｅｒｔ－ブチル（メタ）アクリレート、ペンチル（メタ）アクリレート、ネオペンチル（メタ）アクリレート、２－エチルヘキシル（メタ）アクリレート、イソアミル（メタ）アクリレート、ドデシル（メタ）アクリレート等のアルキル（メタ）アクリレート；及びシクロペンチル（メタ）アクリレート、シクロヘキシル（メタ）アクリレート、エチルシクロヘキシル（メタ）アクリレート、ノルボルニル（メタ）アクリレート、ジシクロペンタニル（メタ）アクリレート、イソボルニル（メタ）アクリレート、アダマンチル（メタ）アクリレート等の脂環式アルキル（メタ）アクリレートなどが挙げられる。アルキル（メタ）アクリレート（ｍ－２）中のアルキル基は置換されていてもよい。置換基としては例えば、メトキシ基、エトキシ基等のアルコキシ基が挙げられる。中でも、ＵＶ照射後の粘着シートの剥離性の観点から、アルキル基の炭素原子数が１～２０の、アルキル（メタ）アクリレート及び脂環式アルキル（メタ）アクリレートが好ましく、メチル（メタ）アクリレート、エチル（メタ）アクリレート、２－メトキシエチル（メタ）アクリレート、プロピル（メタ）アクリレート、ブチル（メタ）アクリレート、２－エチルヘキシル（メタ）アクリレート、ドデシル（メタ）アクリレート、シクロヘキシル（メタ）アクリレート、イソボルニル（メタ）アクリレート、及びジシクロペンタニル（メタ）アクリレートから選択される一種以上がより好ましい。 (Alkyl (meth)acrylate (m-2))
The alkyl (meth)acrylate (m-2) is not particularly limited as long as it does not have a hydroxy group or a carboxy group and has an alkyl group and a (meth)acryloyloxy group. Specifically, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, ) acrylate, neopentyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isoamyl (meth)acrylate, dodecyl (meth)acrylate and other alkyl (meth)acrylates; and cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, ethyl Examples include alicyclic alkyl (meth)acrylates such as cyclohexyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, isobornyl (meth)acrylate, and adamantyl (meth)acrylate. The alkyl group in the alkyl (meth)acrylate (m-2) may be substituted. Examples of the substituent include alkoxy groups such as methoxy and ethoxy groups. Among them, from the viewpoint of peelability of the pressure-sensitive adhesive sheet after UV irradiation, alkyl (meth)acrylates and alicyclic alkyl (meth)acrylates in which the alkyl group has 1 to 20 carbon atoms are preferred, and methyl (meth)acrylate, Ethyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, ) acrylate and dicyclopentanyl (meth)acrylate are more preferred.
　アルキル（メタ）アクリレート（ｍ－２）の含有量は、原料モノマー群（Ｍ）１００モル％に対して、好ましくは１０～９４モル％であり、より好ましくは３０～８５モル％であり、さらに好ましくは５０～８０モル％である。アルキル（メタ）アクリレート（ｍ－２）の含有量が１０モル％以上であると、優れた接着性を得ることができる。アルキル（メタ）アクリレート（ｍ－２）の含有量が９４モル％以下であると、（メタ）アクリル樹脂（Ａ）のヒドロキシ基及びエチレン性不飽和基の含有量を十分に確保することができるため、粘着剤層の凝集力、及びＵＶ照射後の粘着シートの剥離性の観点から、バランスの取れた物性を有する粘着剤層が得られる。 The content of alkyl (meth)acrylate (m-2) is preferably 10 to 94 mol%, more preferably 30 to 85 mol%, and further Preferably it is 50 to 80 mol%. When the content of alkyl (meth)acrylate (m-2) is 10 mol% or more, excellent adhesiveness can be obtained. When the content of alkyl (meth)acrylate (m-2) is 94 mol% or less, a sufficient content of hydroxyl groups and ethylenically unsaturated groups in the (meth)acrylic resin (A) can be ensured. Therefore, an adhesive layer having well-balanced physical properties can be obtained from the viewpoint of the cohesive force of the adhesive layer and the peelability of the adhesive sheet after UV irradiation.
（カルボキシ基含有単量体（ｍ－３））
　カルボキシ基含有単量体（ｍ－３）は、ヒドロキシ基を有さず、カルボキシ基とエチレン性不飽和基とを有するモノマーであれば特に限定されない。例えば、（メタ）アクリル酸、クロトン酸、ビニル安息香酸、アクリル酸のα位ハロアルキル、アルコキシル、ハロゲン、ニトロ、又はシアノ置換体等の不飽和一塩基酸、及びイタコン酸等の不飽和二塩基酸が挙げられる。中でも、粘着剤の製造の容易さから（メタ）アクリル酸が好ましい。 (Carboxy group-containing monomer (m-3))
The carboxyl group-containing monomer (m-3) is not particularly limited as long as it does not have a hydroxyl group and has a carboxyl group and an ethylenically unsaturated group. For example, unsaturated monobasic acids such as (meth)acrylic acid, crotonic acid, vinylbenzoic acid, α-haloalkyl, alkoxyl, halogen, nitro, or cyano substituted products of acrylic acid, and unsaturated dibasic acids such as itaconic acid. can be mentioned. Among these, (meth)acrylic acid is preferred from the viewpoint of ease of production of the adhesive.
　カルボキシ基含有単量体（ｍ－３）を用いる場合、カルボキシ基含有単量体（ｍ－３）の含有量は、原料モノマー群（Ｍ）１００モル％に対して、好ましくは０．１～１０モル％であり、より好ましくは０．５～８．０モル％であり、さらに好ましくは１．０～５．０モル％である。カルボキシ基含有単量体（ｍ－３）の含有量が０．１モル％以上であると、架橋剤（Ｃ）がポリエポキシ化合物である場合に、十分量の架橋量を確保することができ、十分な粘着剤の凝集力を得ることができる。カルボキシ基含有単量体（ｍ－３）の含有量が１０モル％以下であると、（メタ）アクリル樹脂（Ａ）のヒドロキシ基及びエチレン性不飽和基の含有量を十分に確保することができるため、粘着剤層の凝集力、及びＵＶ照射後の粘着シートの剥離性の観点から、バランスの取れた物性を有する粘着剤層が得られる。 When using the carboxy group-containing monomer (m-3), the content of the carboxy group-containing monomer (m-3) is preferably 0.1 to 0.1 to 100 mol% of the raw material monomer group (M). The content is 10 mol%, more preferably 0.5 to 8.0 mol%, even more preferably 1.0 to 5.0 mol%. When the content of the carboxy group-containing monomer (m-3) is 0.1 mol% or more, a sufficient amount of crosslinking can be ensured when the crosslinking agent (C) is a polyepoxy compound. , sufficient cohesive force of the adhesive can be obtained. When the content of the carboxy group-containing monomer (m-3) is 10 mol% or less, it is difficult to ensure a sufficient content of hydroxy groups and ethylenically unsaturated groups in the (meth)acrylic resin (A). Therefore, an adhesive layer having well-balanced physical properties can be obtained from the viewpoint of the cohesive force of the adhesive layer and the peelability of the adhesive sheet after UV irradiation.
　原料モノマー群（Ｍ）において、ヒドロキシ基含有（メタ）アクリレート（ｍ－１）とアルキル（メタ）アクリレート（ｍ－２）とカルボキシ基含有単量体（ｍ－３）のモル比は、（ｍ－１）：（ｍ－２）：（ｍ－３）＝１０～７０：３０～９０：０～１０であることが好ましく、（ｍ－１）：（ｍ－２）：（ｍ－３）＝１５～３５：６５～８５：０～５であることがより好ましい。 In the raw material monomer group (M), the molar ratio of hydroxy group-containing (meth)acrylate (m-1), alkyl (meth)acrylate (m-2) and carboxy group-containing monomer (m-3) is (m -1):(m-2):(m-3)=10-70:30-90:0-10, preferably (m-1):(m-2):(m-3) More preferably, the ratio is 15 to 35:65 to 85:0 to 5.
（その他の単量体（ｍ－４））
　原料モノマー群（Ｍ）は、（ｍ－１）～（ｍ－３）以外のその他の単量体（ｍ－４）を含有してもよい。具体例としては、ブタジエン、ジシクロペンタジエン等のジエン類、スチレン類、不飽和ジカルボン酸ジエステル、その他のビニル化合物類などが挙げられる。 (Other monomers (m-4))
The raw material monomer group (M) may contain monomers (m-4) other than (m-1) to (m-3). Specific examples include dienes such as butadiene and dicyclopentadiene, styrenes, unsaturated dicarboxylic acid diesters, and other vinyl compounds.
　スチレン類の具体例としては、スチレン、スチレンのα－、ｏ－、ｍ－、又はｐ－アルキル誘導体等が挙げられる。 Specific examples of styrenes include styrene, α-, o-, m-, or p-alkyl derivatives of styrene.
　不飽和ジカルボン酸ジエステルの具体例としては、シトラコン酸ジエチル、マレイン酸ジエチル、フマル酸ジエチル、イタコン酸ジエチル等が挙げられる。 Specific examples of unsaturated dicarboxylic acid diesters include diethyl citraconate, diethyl maleate, diethyl fumarate, diethyl itaconate, and the like.
　その他のビニル化合物類の具体例としては、ノルボルネン（ビシクロ［２．２．１］ヘプト－２－エン）、５－メチルビシクロ［２．２．１］ヘプト－２－エン、５－エチルビシクロ［２．２．１］ヘプト－２－エン、テトラシクロ［４．４．０．１２，５．１７，１０］ドデカ－３－エン、８－メチルテトラシクロ［４．４．０．１２，５．１７，１０］ドデカ－３－エン、８－エチルテトラシクロ［４．４．０．１２，５．１７，１０］ドデカ－３－エン、トリシクロ［５．２．１．０２，６］デカ－８－エン、トリシクロ［５．２．１．０２，６］デカ－３－エン、トリシクロ［４．４．０．１２，５］ウンデカ－３－エン、トリシクロ［６．２．１．０１，８］ウンデカ－９－エン、トリシクロ［６．２．１．０１，８］ウンデカ－４－エン、テトラシクロ［４．４．０．１２，５．１７，１０．０１，６］ドデカ－３－エン、８－メチルテトラシクロ［４．４．０．１２，５．１７，１０．０１，６］ドデカ－３－エン、８－エチリデンテトラシクロ［４．４．０．１２，５．１７，１２］ドデカ－３－エン、８－エチリデンテトラシクロ［４．４．０．１２，５．１７，１０．０１，６］ドデカ－３－エン、ペンタシクロ［６．５．１．１３，６．０２，７．０９，１３］ペンタデカ－４－エン、ペンタシクロ［７．４．０．１２，５．１９，１２．０８，１３］ペンタデカ－３－エン、（メタ）アクリル酸アニリド、ビニルピリジン、酢酸ビニル等が挙げられる。 Specific examples of other vinyl compounds include norbornene (bicyclo[2.2.1]hept-2-ene), 5-methylbicyclo[2.2.1]hept-2-ene, 5-ethylbicyclo[ 2.2.1] hept-2-ene, tetracyclo[4.4.0.1 2,5 . 1 7,10 ] dodec-3-ene, 8-methyltetracyclo[4.4.0.1 2,5 . 1 7,10 ] dodec-3-ene, 8-ethyltetracyclo[4.4.0.1 2,5 . 1 7,10 ] dodec-3-ene, tricyclo[5.2.1.0 2,6 ]dec-8-ene, tricyclo[5.2.1.0 2,6 ]dec-3-ene, tricyclo [4.4.0.1 2,5 ] undec-3-ene, tricyclo[6.2.1.0 1,8 ] undec-9-ene, tricyclo[6.2.1.0 1,8 ] undec-4-ene, tetracyclo[4.4.0.1 2,5 . 1 7, 10 . 0 1,6 ] dodec-3-ene, 8-methyltetracyclo[4.4.0.1 2,5 . 1 7, 10 . 0 1,6 ] dodec-3-ene, 8-ethylidene tetracyclo[4.4.0.1 2,5 . 1 7,12 ] dodec-3-ene, 8-ethylidene tetracyclo[4.4.0.1 2,5 . 1 7, 10 . 0 1,6 ] dodec-3-ene, pentacyclo[6.5.1.1 3,6 . 0 2,7 . 0 9,13 ] pentadec-4-ene, pentacyclo[7.4.0.1 2,5 . 1 9, 12 . 0 8,13 ]pentadec-3-ene, (meth)acrylic acid anilide, vinylpyridine, vinyl acetate, and the like.
（可逆的付加開裂連鎖移動剤（ＲＡＦＴ剤））
　ＲＡＦＴ剤としては、公知のものを特に制限なく使用することができる。例えば、下記式（１）、式（２）、式（３）、又は式（４）で表される硫黄系の化合物（トリチオカーボネート、ジチオエステル、ジチオカーボネート、及びジチオカルバマート）が好ましい。 (Reversible addition-fragmentation chain transfer agent (RAFT agent))
As the RAFT agent, any known RAFT agent can be used without particular limitation. For example, sulfur-based compounds (trithiocarbonate, dithioester, dithiocarbonate, and dithiocarbamate) represented by the following formula (1), formula (2), formula (3), or formula (4) are preferred.
≪トリチオカーボネート≫
（式（１）において、Ｒ１ａ及びＲ１ｂは、同一又は異なって、水素原子、炭化水素基、カルボキシ基、又はシアノ基を示し、Ｒ１ｃは、シアノ基、シアノ基若しくはカルボキシ基で置換されていてよい飽和若しくは不飽和の脂肪族炭化水素基、又は置換されていてよいフェニル基を示し、Ｒ２は、水素原子の一部がカルボキシ基で置換されていてよい飽和若しくは不飽和の脂肪族炭化水素基、又は置換されていてよいベンジル基を示す。） ≪Trithiocarbonate≫
(In formula (1), R 1a and R 1b are the same or different and represent a hydrogen atom, a hydrocarbon group, a carboxy group, or a cyano group, and R 1c is substituted with a cyano group, a cyano group, or a carboxy group. R2 represents a saturated or unsaturated aliphatic hydrocarbon group that may be substituted with a carboxy group, or a phenyl group that may be substituted; Indicates a hydrocarbon group or an optionally substituted benzyl group.)
≪ジチオエステル≫
（式（２）において、Ｒ３ａ及びＲ３ｂは、同一又は異なって、水素原子、炭化水素基、又はシアノ基を示し、Ｒ３ｃは、カルボキシ基、アセトキシメチル基、又はシアノ基若しくはカルボキシ基で置換されていてよい炭化水素基を示し、Ｒ４は、炭化水素基を示す。） ≪Dithioester≫
(In formula (2), R 3a and R 3b are the same or different and represent a hydrogen atom, a hydrocarbon group, or a cyano group, and R 3c is a carboxy group, an acetoxymethyl group, a cyano group, or a carboxy group. represents a hydrocarbon group that may be substituted, and R 4 represents a hydrocarbon group.)
≪ジチオカーボネート≫
（式（３）において、Ｒ５ａ及びＲ５ｂは、同一又は異なって、水素原子、炭化水素基、炭素原子数１～３の飽和脂肪族炭化水素基で置換されていてよいカルボキシ基、又はシアノ基を示し、Ｒ５ｃは、アルコキシ基で置換されていてよい炭化水素基を示し、Ｒ６は、炭化水素基を示す。） ≪Dithiocarbonate≫
(In formula (3), R 5a and R 5b are the same or different and are a hydrogen atom, a hydrocarbon group, a carboxy group which may be substituted with a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms, or a cyano (R 5c represents a hydrocarbon group which may be substituted with an alkoxy group, and R 6 represents a hydrocarbon group.)
≪ジチオカルバマート≫
（式（４）において、Ｒ７ａ及びＲ７ｂは、同一又は異なって、水素原子、又は炭化水素基を示し、Ｒ７ｃは、シアノ基を示し、Ｒ８及びＲ９は、同一又は異なって、炭化水素基を示すか、Ｒ８とＲ９が結合して、炭素原子数１～３の飽和脂肪族炭化水素基若しくは塩素原子で置換されていてよいピラゾール環を形成してもよい。） ≪Dithiocarbamate≫
(In formula (4), R 7a and R 7b are the same or different and represent a hydrogen atom or a hydrocarbon group, R 7c is a cyano group, R 8 and R 9 are the same or different, It may represent a hydrocarbon group, or R 8 and R 9 may combine to form a pyrazole ring which may be substituted with a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms or a chlorine atom.)
　式（１）中、Ｒ１ａ及びＲ１ｂで示される炭化水素基としては、例えば、炭素原子数１～２０の、直鎖、分岐又は環状の、飽和又は不飽和の炭化水素基が挙げられ、中でも、炭素原子数１～１２の、直鎖、分岐又は環状の、飽和又は不飽和の炭化水素基が好ましい。上記炭化水素基としては、例えば、メチル基、エチル基、ｎ－プロピル基、イソプロピル基、ｎ－ブチル基、イソブチル基、ｔｅｒｔ－ブチル基、シクロヘキシル基、ドデシル基、オクタデシル基等の炭素原子数１～２０の、直鎖、分岐又は環状の飽和脂肪族炭化水素基；フェニル基等の炭素原子数６～１２のアリール基；ベンジル基、フェネチル基等の炭素原子数７～１０のアリールアルキル基などが挙げられる。式（１）中、Ｒ１ｃで示される飽和若しくは不飽和の脂肪族炭化水素基としては、例えば、炭素原子数１～２０の、直鎖、分岐又は環状の、飽和又は不飽和の脂肪族炭化水素基が挙げられ、中でも、炭素原子数１～１２の、直鎖、分岐又は環状の、飽和又は不飽和の脂肪族炭化水素基が好ましい。上記脂肪族炭化水素基としては、例えば、メチル基、エチル基、ｎ－プロピル基、イソプロピル基、ｎ－ブチル基、イソブチル基、ｔｅｒｔ－ブチル基、シクロヘキシル基、ドデシル基、オクタデシル基等の炭素原子数１～２０の、直鎖、分岐又は環状の飽和脂肪族炭化水素基などが挙げられる。式（１）中、Ｒ１ｃで示される飽和若しくは不飽和の脂肪族炭化水素基が有する水素原子の例えば１～３個は、カルボキシ基、又はシアノ基で置換されていてよく、カルボキシ基は炭素原子数１～３の飽和脂肪族炭化水素基でさらに置換されていてよい。式（１）中、Ｒ１ｃで示される置換されていてよいフェニル基の置換基としては、置換カルバモイル基、ヒドロキシ基で置換されていてよい炭素原子数２～５のアルコキシカルボニル基、炭素原子数３～５のアルケニルオキシカルボニル基等が挙げられる。上記置換カルバモイル基の置換基としては、ヒドロキシ基又はアセチルオキシ基で置換されていてよい炭素原子数１～３の飽和脂肪族炭化水素基等が挙げられる。式（１）中、Ｒ２で示される飽和若しくは不飽和の脂肪族炭化水素基としては、例えば、炭素原子数１～２０の、直鎖、分岐又は環状の、飽和又は不飽和の脂肪族炭化水素基が挙げられ、中でも、炭素原子数１～１２の脂肪族炭化水素基が好ましい。上記脂肪族炭化水素基としては、例えば、メチル基、エチル基、ｎ－プロピル基、イソプロピル基、ｎ－ブチル基、イソブチル基、ｔｅｒｔ－ブチル基、シクロヘキシル基、ドデシル基、オクタデシル基等の炭素原子数１～２０の、直鎖、分岐又は環状の飽和脂肪族炭化水素基などが挙げられる。式（１）中、Ｒ２で示される飽和若しくは不飽和の脂肪族炭化水素基が有する水素原子の例えば１～３個は、カルボキシ基で置換されていてよい。式（１）中、Ｒ２で示される置換されていてよいベンジル基の置換基としては、置換カルバモイル基、ヒドロキシ基で置換されていてよい炭素原子数２～５のアルコキシカルボニル基、炭素原子数３～５のアルケニルオキシカルボニル基等が挙げられる。上記置換カルバモイル基の置換基としては、ヒドロキシ基又はアセチルオキシ基で置換されていてよい炭素原子数１～３の飽和脂肪族炭化水素基等が挙げられる。これらの中でも、Ｒ１ａ及びＲ１ｂが、同一又は異なって、水素原子、炭素原子数１～４の炭化水素基、又はカルボキシ基であり、Ｒ１ｃが炭素原子数１～４の炭化水素基、又は置換されていてよいフェニル基であり、Ｒ２が炭素原子数１～２０の、直鎖、分岐若しくは環状の、飽和若しくは不飽和の脂肪族炭化水素基、又は置換されていてよいベンジル基である式（１）で示される化合物が好ましく、Ｒ１ａ及びＲ１ｂが、水素原子、メチル基若しくはエチル基と、カルボキシ基との組み合わせ、又は水素原子であり、Ｒ１ｃがメチル基、エチル基、又は置換されていてよいフェニル基であり、Ｒ２が炭素原子数１～２０の直鎖の飽和脂肪族炭化水素基、又は置換されていてよいベンジル基である式（１）で示される化合物がより好ましい。 In formula (1), the hydrocarbon group represented by R 1a and R 1b includes, for example, a straight chain, branched or cyclic, saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, Among these, straight chain, branched or cyclic, saturated or unsaturated hydrocarbon groups having 1 to 12 carbon atoms are preferred. Examples of the hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a cyclohexyl group, a dodecyl group, an octadecyl group, etc. ~20 linear, branched or cyclic saturated aliphatic hydrocarbon groups; aryl groups with 6 to 12 carbon atoms such as phenyl groups; arylalkyl groups with 7 to 10 carbon atoms such as benzyl groups and phenethyl groups, etc. can be mentioned. In formula (1), the saturated or unsaturated aliphatic hydrocarbon group represented by R 1c is, for example, a linear, branched or cyclic saturated or unsaturated aliphatic hydrocarbon group having 1 to 20 carbon atoms. Hydrogen groups are mentioned, and among them, linear, branched or cyclic, saturated or unsaturated aliphatic hydrocarbon groups having 1 to 12 carbon atoms are preferred. Examples of the aliphatic hydrocarbon group include carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, cyclohexyl group, dodecyl group, and octadecyl group. Examples include 1 to 20 linear, branched, or cyclic saturated aliphatic hydrocarbon groups. In formula (1), for example, 1 to 3 hydrogen atoms of the saturated or unsaturated aliphatic hydrocarbon group represented by R 1c may be substituted with a carboxy group or a cyano group, and the carboxy group is a carbon It may be further substituted with a saturated aliphatic hydrocarbon group having 1 to 3 atoms. In formula (1), substituents for the optionally substituted phenyl group represented by R 1c include a substituted carbamoyl group, an alkoxycarbonyl group having 2 to 5 carbon atoms which may be substituted with a hydroxy group, and a carbon atom number Examples include 3 to 5 alkenyloxycarbonyl groups. Examples of the substituent of the substituted carbamoyl group include a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a hydroxy group or an acetyloxy group. In formula (1), the saturated or unsaturated aliphatic hydrocarbon group represented by R 2 is, for example, a linear, branched or cyclic saturated or unsaturated aliphatic hydrocarbon group having 1 to 20 carbon atoms. Examples include hydrogen groups, and among them, aliphatic hydrocarbon groups having 1 to 12 carbon atoms are preferred. Examples of the aliphatic hydrocarbon group include carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, cyclohexyl group, dodecyl group, and octadecyl group. Examples include 1 to 20 linear, branched, or cyclic saturated aliphatic hydrocarbon groups. In formula (1), for example, 1 to 3 hydrogen atoms of the saturated or unsaturated aliphatic hydrocarbon group represented by R 2 may be substituted with a carboxy group. In formula (1), substituents for the optionally substituted benzyl group represented by R 2 include a substituted carbamoyl group, an alkoxycarbonyl group having 2 to 5 carbon atoms which may be substituted with a hydroxy group, and a carbon atom number Examples include 3 to 5 alkenyloxycarbonyl groups. Examples of the substituent of the substituted carbamoyl group include a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a hydroxy group or an acetyloxy group. Among these, R 1a and R 1b are the same or different and are a hydrogen atom, a hydrocarbon group having 1 to 4 carbon atoms, or a carboxy group, and R 1c is a hydrocarbon group having 1 to 4 carbon atoms, or a phenyl group which may be substituted, and R 2 is a linear, branched or cyclic, saturated or unsaturated aliphatic hydrocarbon group having 1 to 20 carbon atoms, or a benzyl group which may be substituted. A compound represented by a certain formula (1) is preferred, in which R 1a and R 1b are a hydrogen atom, a combination of a methyl group or an ethyl group, and a carboxy group, or a hydrogen atom, and R 1c is a methyl group, an ethyl group, or a phenyl group which may be substituted, and a compound represented by formula (1) in which R 2 is a linear saturated aliphatic hydrocarbon group having 1 to 20 carbon atoms, or a benzyl group which may be substituted; More preferred.
　式（２）中、Ｒ３ａ、Ｒ３ｂ、Ｒ３ｃ及びＲ４で示される炭化水素基としては、例えば、炭素原子数１～２０の、直鎖、分岐又は環状の、飽和又は不飽和の炭化水素基が挙げられ、中でも、炭素原子数１～１２の、直鎖、分岐又は環状の、飽和又は不飽和の炭化水素基が好ましい。上記炭化水素基としては、例えば、メチル基、エチル基、ｎ－プロピル基、イソプロピル基、ｎ－ブチル基、イソブチル基、ｔｅｒｔ－ブチル基、シクロヘキシル基、ドデシル基、オクタデシル基等の炭素原子数１～２０の、直鎖、分岐又は環状の飽和脂肪族炭化水素基；フェニル基等の炭素原子数６～１２のアリール基；ベンジル基、フェネチル基等の炭素原子数７～１０のアリールアルキル基などが挙げられる。式（２）中、Ｒ３ｃで示されるシアノ基若しくはカルボキシ基で置換されていてよい炭化水素基としては、例えば、上述の炭化水素基が有する水素原子の１～３個がシアノ基又はカルボキシ基で置換された基等が挙げられる。これらの中でも、Ｒ３ａ及びＲ３ｂが、同一又は異なって、炭素原子数１～４の直鎖の飽和炭化水素基であり、Ｒ３ｃがアリール基であり、Ｒ４がアリール基又はベンジル基である式（２）で示される化合物が好ましく、Ｒ３ａ及びＲ３ｂが、同一又は異なって、メチル基又はエチル基であり、Ｒ３ｃがフェニル基であり、Ｒ４がフェニル基又はベンジル基である式（２）で示される化合物がより好ましい。 In formula (2), the hydrocarbon group represented by R 3a , R 3b , R 3c and R 4 is, for example, a linear, branched or cyclic, saturated or unsaturated carbonized group having 1 to 20 carbon atoms. Hydrogen groups are mentioned, and among them, straight chain, branched or cyclic, saturated or unsaturated hydrocarbon groups having 1 to 12 carbon atoms are preferred. Examples of the hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a cyclohexyl group, a dodecyl group, an octadecyl group, etc. ~20 linear, branched or cyclic saturated aliphatic hydrocarbon groups; aryl groups with 6 to 12 carbon atoms such as phenyl groups; arylalkyl groups with 7 to 10 carbon atoms such as benzyl groups and phenethyl groups, etc. can be mentioned. In formula (2), the hydrocarbon group which may be substituted with a cyano group or a carboxy group represented by R 3c is, for example, a hydrocarbon group in which 1 to 3 of the hydrogen atoms of the above-mentioned hydrocarbon group are cyano groups or carboxy groups. Examples include groups substituted with . Among these, R 3a and R 3b are the same or different and are linear saturated hydrocarbon groups having 1 to 4 carbon atoms, R 3c is an aryl group, and R 4 is an aryl group or a benzyl group. A compound represented by a certain formula (2) is preferred, in which R 3a and R 3b are the same or different and are a methyl group or an ethyl group, R 3c is a phenyl group, and R 4 is a phenyl group or a benzyl group. A compound represented by formula (2) is more preferred.
　式（３）中、Ｒ５ａ、Ｒ５ｂ、Ｒ５ｃ及びＲ６で示される炭化水素基としては、例えば、炭素原子数１～２０の、直鎖、分岐又は環状の、飽和又は不飽和の炭化水素基が挙げられ、中でも、炭素原子数１～１２の、直鎖、分岐又は環状の、飽和又は不飽和の炭化水素基が好ましい。上記炭化水素基としては、例えば、メチル基、エチル基、ｎ－プロピル基、イソプロピル基、ｎ－ブチル基、イソブチル基、ｔｅｒｔ－ブチル基、シクロヘキシル基、ドデシル基、オクタデシル基等の炭素原子数１～２０の、直鎖、分岐又は環状の飽和脂肪族炭化水素基；フェニル基等の炭素原子数６～１２のアリール基；ベンジル基、フェネチル基等の炭素原子数７～１０のアリールアルキル基などが挙げられる。式（３）中、Ｒ５ｃで示されるアルコキシ基で置換されていてよい炭化水素基としては、例えば、上述の炭化水素基が有する水素原子の１～３個がアルコキシ基で置換された基等が挙げられる。 In formula (3), the hydrocarbon group represented by R 5a , R 5b , R 5c and R 6 is, for example, a linear, branched or cyclic, saturated or unsaturated carbonized group having 1 to 20 carbon atoms. Hydrogen groups are mentioned, and among them, straight chain, branched or cyclic, saturated or unsaturated hydrocarbon groups having 1 to 12 carbon atoms are preferred. Examples of the hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a cyclohexyl group, a dodecyl group, an octadecyl group, etc. ~20 linear, branched or cyclic saturated aliphatic hydrocarbon groups; aryl groups with 6 to 12 carbon atoms such as phenyl groups; arylalkyl groups with 7 to 10 carbon atoms such as benzyl groups and phenethyl groups, etc. can be mentioned. In formula (3), the hydrocarbon group which may be substituted with an alkoxy group represented by R 5c includes, for example, a group in which 1 to 3 of the hydrogen atoms of the above-mentioned hydrocarbon group are substituted with an alkoxy group. can be mentioned.
　式（４）中、Ｒ７ａ、Ｒ７ｂ、Ｒ８及びＲ９で示される炭化水素基としては、例えば、炭素原子数１～２０の、直鎖、分岐又は環状の、飽和又は不飽和の炭化水素基が挙げられ、中でも、炭素原子数１～１２の、直鎖、分岐又は環状の、飽和又は不飽和の炭化水素基が好ましい。上記炭化水素基としては、例えば、メチル基、エチル基、ｎ－プロピル基、イソプロピル基、ｎ－ブチル基、イソブチル基、ｔｅｒｔ－ブチル基、シクロヘキシル基、ドデシル基、オクタデシル基等の炭素原子数１～２０の、直鎖、分岐又は環状の飽和脂肪族炭化水素基；フェニル基等の炭素原子数６～１２のアリール基；ベンジル基、フェネチル基等の炭素原子数７～１０のアリールアルキル基などが挙げられる。Ｒ８及びＲ９は、式（４）の窒素原子とともにピラゾール環を形成していてもよい。当該ピラゾール環は炭素原子数１～３の飽和脂肪族炭化水素基又は塩素原子で置換されていてよい。 In formula (4), the hydrocarbon group represented by R 7a , R 7b , R 8 and R 9 is, for example, a linear, branched or cyclic, saturated or unsaturated carbonized group having 1 to 20 carbon atoms. Hydrogen groups are mentioned, and among them, linear, branched or cyclic, saturated or unsaturated hydrocarbon groups having 1 to 12 carbon atoms are preferred. Examples of the hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a cyclohexyl group, a dodecyl group, an octadecyl group, etc. ~20 linear, branched, or cyclic saturated aliphatic hydrocarbon groups; aryl groups with 6 to 12 carbon atoms such as phenyl groups; arylalkyl groups with 7 to 10 carbon atoms such as benzyl groups and phenethyl groups, etc. can be mentioned. R 8 and R 9 may form a pyrazole ring together with the nitrogen atom of formula (4). The pyrazole ring may be substituted with a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms or a chlorine atom.
　式（１）～（４）に示すＲＡＦＴ剤の存在下で重合を行うと、ラジカル種がＲＡＦＴ剤中の硫黄原子とその硫黄原子に隣接する炭素原子との間で連鎖反応しながら、重合が進行する。中でも、重合容易性の観点から、式（１）及び（２）に示すＲＡＦＴ剤が好ましい。 When polymerization is carried out in the presence of the RAFT agents shown in formulas (1) to (4), radical species undergo a chain reaction between the sulfur atoms in the RAFT agent and the carbon atoms adjacent to the sulfur atoms, leading to polymerization. proceed. Among these, RAFT agents represented by formulas (1) and (2) are preferred from the viewpoint of ease of polymerization.
　ＲＡＦＴ剤の多くは、商業的に入手可能である。商業的に入手できないものは、公知乃至慣用の方法により容易に合成することができる。 Many RAFT agents are commercially available. Those that are not commercially available can be easily synthesized by known or conventional methods.
　ＲＡＦＴ剤の具体例としては、Ｓ－シアノメチル－Ｓ－ドデシルトリチオカーボネート、２－［（ドデシルスルファニルチオカルボニル）スルファニル］プロパン酸、２－｛［（２-カルボキシエチル）スルファニルチオカルボニル］スルファニル｝プロパン酸、ビス｛４－[エチル－(２－ヒドロキシエチル)カルバモイル]ベンジル｝トリチオカーボネート、４－［（２－カルボキシエチルスルファニルチオカルボニル）スルファニル］－４－シアノペンタン酸、４－シアノ－４－［（ドデシルスルファニルチオカルボニル）スルファニル］ペンタン酸、Ｓ，Ｓ－ジベンジルトリチオカーボネート、メチル４－シアノ－４－［（ドデシルスルファニルチオカルボニル）スルファニル］ペンタノエート、２－シアノ－２－プロピルドデシルトリチオカーボネート、ビス［４－（アリルオキシカルボニル）ベンジル］トリチオカーボネート、ビス［４－（２，３－ジヒドロキシプロポキシカルボニル）ベンジル］トリチオカーボネート、ビス｛４－［エチル－（２－アセチルオキシエチル）カルバモイル］ベンジル｝トリチオカーボネート、ビス［４－（２－ヒドロキシエトキシカルボニル）ベンジル］トリチオカーボネート等のトリチオカーボネート；ジチオプロピオン酸シアノエチル、ジチオプロピオン酸ベンジル、ジチオ安息香酸ベンジル、ジチオ安息香酸アセトキシエチル、２－フェニル－２－プロピルジチオ安息香酸、２－シアノ－２－プロピルジチオ安息香酸、４－シアノ－４－(フェニルカルボノチオイルチオ)ペンタン酸、Ｓ－(チオベンゾイル)チオグリコール酸等のジチオエステル；２－[(エトキシカルボノチオイル)チオ]プロピオン酸エチル、Ｏ－エチル－Ｓ－（２－プロポキシエチル）ジチオカーボネート、Ｏ－エチル－Ｓ－（１－シアノ－１－メチルエチル）ジチオカーボネート等のジチオカーボネート；２－シアノ－２－プロピルジエチルジチオカルバマート、２’－シアノブタン－２’－イル４－クロロ－３，５－ジメチルピラゾール－１－ジチオカルバマート、２’－シアノブタン－２’－イル３，５－ジメチルピラゾール－１－ジチオカルバマート、シアノメチル３，５－ジメチルピラゾール－１－ジチオカルバマート、シアノメチルＮ－メチル－Ｎ－フェニルジチオカルバマート等のジチオカルバマートなどが挙げられる。これらのうち、（メタ）アクリル樹脂（Ａ）の重合容易性の観点から、トリチオカーボネート、及びジチオエステルが好ましく、２－［（ドデシルスルファニルチオカルボニル）スルファニル］プロパン酸、２－｛［（２-カルボキシエチル）スルファニルチオカルボニル］スルファニル｝プロパン酸、２－フェニル－２－プロピルジチオ安息香酸、Ｓ，Ｓ－ジベンジルトリチオカーボネート、及びビス｛４－［エチル－（２－アセチルオキシエチル）カルバモイル］ベンジル｝トリチオカーボネートがより好ましい。 Specific examples of RAFT agents include S-cyanomethyl-S-dodecyl trithiocarbonate, 2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propanoic acid, 2-{[(2-carboxyethyl)sulfanylthiocarbonyl]sulfanyl}propane. Acid, bis{4-[ethyl-(2-hydroxyethyl)carbamoyl]benzyl}trithiocarbonate, 4-[(2-carboxyethylsulfanylthiocarbonyl)sulfanyl]-4-cyanopentanoic acid, 4-cyano-4- [(dodecylsulfanylthiocarbonyl)sulfanyl]pentanoic acid, S,S-dibenzyltrithiocarbonate, methyl 4-cyano-4-[(dodecylsulfanylthiocarbonyl)sulfanyl]pentanoate, 2-cyano-2-propyldodecyltrithio carbonate, bis[4-(allyloxycarbonyl)benzyl]trithiocarbonate, bis[4-(2,3-dihydroxypropoxycarbonyl)benzyl]trithiocarbonate, bis{4-[ethyl-(2-acetyloxyethyl) Trithiocarbonates such as carbamoyl]benzyl}trithiocarbonate, bis[4-(2-hydroxyethoxycarbonyl)benzyl]trithiocarbonate; cyanoethyl dithiopropionate, benzyl dithiopropionate, benzyl dithiobenzoate, acetoxyethyl dithiobenzoate , 2-phenyl-2-propyldithiobenzoic acid, 2-cyano-2-propyldithiobenzoic acid, 4-cyano-4-(phenylcarbonothioylthio)pentanoic acid, S-(thiobenzoyl)thioglycolic acid, etc. Dithioester; ethyl 2-[(ethoxycarbonothioyl)thio]propionate, O-ethyl-S-(2-propoxyethyl)dithiocarbonate, O-ethyl-S-(1-cyano-1-methylethyl)dithio Dithiocarbonates such as carbonate; 2-cyano-2-propyldiethyldithiocarbamate, 2'-cyanobutan-2'-yl 4-chloro-3,5-dimethylpyrazole-1-dithiocarbamate, 2'-cyanobutane-2 Examples include dithiocarbamates such as '-yl 3,5-dimethylpyrazole-1-dithiocarbamate, cyanomethyl 3,5-dimethylpyrazole-1-dithiocarbamate, and cyanomethyl N-methyl-N-phenyldithiocarbamate. . Among these, trithiocarbonate and dithioester are preferred from the viewpoint of ease of polymerization of the (meth)acrylic resin (A), and 2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propanoic acid, 2-{[(2 -carboxyethyl)sulfanylthiocarbonyl]sulfanyl}propanoic acid, 2-phenyl-2-propyldithiobenzoic acid, S,S-dibenzyltrithiocarbonate, and bis{4-[ethyl-(2-acetyloxyethyl)carbamoyl) ]benzyl}trithiocarbonate is more preferred.
　ＲＡＦＴ剤は、単独で使用してもよいし、２種以上を組み合わせて使用してもよい。 RAFT agents may be used alone or in combination of two or more.
（ラジカル重合開始剤）
　ＲＡＦＴ重合は、ラジカル重合開始剤の存在下に行うことが好ましい。ラジカル重合開始剤としては、例えば、通常の有機系ラジカル重合開始剤が挙げられ、具体的には、例えば、２，２’－アゾビス（イソブチロニトリル）、２，２’－アゾビス（４－メトキシ－２，４－ジメチルバレロニトリル）、２，２’－アゾビス（２，４－ジメチルバレロニトリル）、２，２’－アゾビス（２－メチルブチロニトリル）、１，１’－アゾビス（シクロヘキサン－１－カルボニトリル）、２，２’－アゾビス（２，４，４－トリメチルペンタン）、ジメチル－２，２’－アゾビス（２－メチルプロピオネート）等のアゾ系重合開始剤；及びベンゾイルパーオキサイド、ｔ－ブチルハイドロパーオキサイド、ジ－ｔ－ブチルパーオキサイド、ｔ－ブチルパーオキシベンゾエート、ジクミルパーオキサイド、１，１－ビス（ｔ－ブチルパーオキシ）－３，３，５－トリメチルシクロヘキサン、１，１－ビス（ｔ－ブチルパーオキシ）シクロドデカン等の過酸化物系重合開始剤などの油溶性重合開始剤が挙げられる。 (radical polymerization initiator)
RAFT polymerization is preferably performed in the presence of a radical polymerization initiator. Examples of the radical polymerization initiator include ordinary organic radical polymerization initiators, specifically, for example, 2,2'-azobis(isobutyronitrile), 2,2'-azobis(4- methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane) -1-carbonitrile), 2,2'-azobis(2,4,4-trimethylpentane), dimethyl-2,2'-azobis(2-methylpropionate), and other azo polymerization initiators; and benzoyl Peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, t-butyl peroxybenzoate, dicumyl peroxide, 1,1-bis(t-butylperoxy)-3,3,5-trimethyl Examples include oil-soluble polymerization initiators such as peroxide-based polymerization initiators such as cyclohexane and 1,1-bis(t-butylperoxy)cyclododecane.
　ラジカル重合開始剤は、単独で使用してもよいし、２種以上を組み合わせて使用してもよい。 The radical polymerization initiators may be used alone or in combination of two or more.
　ラジカル重合開始剤の使用量は、原料モノマー群（Ｍ）の総量１００質量部に対して、０．００１～５質量部であることが好ましく、０．００５～３質量部であることがより好ましく、０．０１～１質量部であることが更に好ましい。 The amount of the radical polymerization initiator used is preferably 0.001 to 5 parts by mass, more preferably 0.005 to 3 parts by mass, based on 100 parts by mass of the total amount of the raw material monomer group (M). , more preferably 0.01 to 1 part by mass.
（溶媒）
　ＲＡＦＴ重合する際に用いる溶媒としては、一般的な溶媒を用いることができる。溶媒としては、例えば、酢酸エチル、酢酸プロピル、酢酸ブチル等のエステル；トルエン、キシレン、ベンゼン等の芳香族炭化水素；ヘキサン、ヘプタン等の脂肪族炭化水素；シクロヘキサン、メチルシクロヘキサン等の脂環式炭化水素；メチルエチルケトン、メチルイソブチルケトン等のケトン；エチレングリコール、プロピレングリコール、ジプロピレングリコール等のグリコール；メチルセロソルブ、プロピレングリコールモノメチルエーテル、ジプロピレングリコールモノメチルエーテル等のグリコールエーテル；及びエチレングリコールジアセテート、プロピレングリコールモノメチルエーテルアセテート等のグリコールエステルが挙げられる。溶媒は、単独で使用してもよいし、２種以上を組み合わせて使用してもよい。 (solvent)
As the solvent used for RAFT polymerization, common solvents can be used. Examples of solvents include esters such as ethyl acetate, propyl acetate, and butyl acetate; aromatic hydrocarbons such as toluene, xylene, and benzene; aliphatic hydrocarbons such as hexane and heptane; and alicyclic carbonization such as cyclohexane and methylcyclohexane. Hydrogen; Ketones such as methyl ethyl ketone and methyl isobutyl ketone; Glycols such as ethylene glycol, propylene glycol and dipropylene glycol; Glycol ethers such as methyl cellosolve, propylene glycol monomethyl ether and dipropylene glycol monomethyl ether; and ethylene glycol diacetate and propylene glycol Examples include glycol esters such as monomethyl ether acetate. The solvents may be used alone or in combination of two or more.
（反応条件）
　ＲＡＦＴ重合の反応温度は、使用するラジカル重合開始剤の種類にもよるが、通常３０℃～１３０℃であり、４０℃～１２０℃であることが好ましく、５０℃～１１０℃であることがより好ましい。ＲＡＦＴ重合時の温度が３０℃以上であると、十分な反応速度を得ることができる。ＲＡＦＴ重合時の温度が１３０℃以下であると、製造時の危険性が少ない。 (Reaction conditions)
The reaction temperature for RAFT polymerization depends on the type of radical polymerization initiator used, but is usually 30°C to 130°C, preferably 40°C to 120°C, more preferably 50°C to 110°C. preferable. When the temperature during RAFT polymerization is 30° C. or higher, a sufficient reaction rate can be obtained. When the temperature during RAFT polymerization is 130° C. or lower, there is little risk during production.
　ＲＡＦＴ重合の反応時間は、使用する原料モノマー群（Ｍ）、ＲＡＦＴ剤、及びラジカル重合開始剤の種類にもよるが、通常３時間～３０時間であり、４時間～２０時間であることが好ましく、５時間～１５時間であることがより好ましい。反応時間が３時間以上であると、原料モノマー群（Ｍ）から共重合体（Ａ－０）を適切な重合度で製造することができ、反応時間が３０時間以下であると、効率的に製造を実施することができる。 The reaction time for RAFT polymerization depends on the raw material monomer group (M) used, the RAFT agent, and the type of radical polymerization initiator, but is usually 3 to 30 hours, preferably 4 to 20 hours. , more preferably from 5 hours to 15 hours. When the reaction time is 3 hours or more, the copolymer (A-0) can be produced from the raw material monomer group (M) with an appropriate degree of polymerization, and when the reaction time is 30 hours or less, the copolymer (A-0) can be produced efficiently. Manufacturing can be carried out.
＜工程（ｉｉ）＞
　（メタ）アクリル樹脂（Ａ）は、共重合体（Ａ－０）が有するヒドロキシ基含有（メタ）アクリレート（ｍ－１）由来の側鎖ヒドロキシ基の一部にイソシアナト基含有エチレン性不飽和化合物（ａ）を付加することにより得られる。共重合体（Ａ－０）の側鎖ヒドロキシ基の全部にイソシアナト基含有エチレン性不飽和化合物（ａ）を付加すると、後述の架橋剤（Ｃ）との反応箇所がなくなるため、付加は側鎖ヒドロキシ基の一部にとどめる。具体的には、側鎖ヒドロキシ基を１００モル％としたとき、付加反応させるのは、５.０～９９モル％であることが好ましい。イソシアナト基含有エチレン性不飽和化合物（ａ）を付加する方法としては、特に限定されず、本明細書の技術分野において公知の方法を用いることができる。（メタ）アクリル樹脂（Ａ）は、側鎖にエチレン性不飽和基を有するため、末端にエチレン性不飽和基が導入された（メタ）アクリル共重合体に比べ、架橋点間の分子鎖の長さが相対的に短く、ＵＶ照射後に粘着力を大きく低下させることができる。したがって、（メタ）アクリル樹脂（Ａ）を用いた粘着シートは、被着体からの剥離性に優れる。加えて、（メタ）アクリル樹脂（Ａ）は、適切な分子量分布を有するため、メタアクリル樹脂（Ａ）を用いて製造された粘着剤組成物は、接着剤層に対して優れた密着性を有する。したがって、（メタ）アクリル樹脂（Ａ）を用いて製造された粘着剤組成物は、ダイシング・ダイボンド一体型フィルムの粘着剤層に好適に用いられる。 <Step (ii)>
The (meth)acrylic resin (A) is an ethylenically unsaturated compound containing an isocyanato group in a part of the side chain hydroxyl group derived from the hydroxyl group-containing (meth)acrylate (m-1) possessed by the copolymer (A-0). Obtained by adding (a). When the isocyanato group-containing ethylenically unsaturated compound (a) is added to all of the side chain hydroxy groups of the copolymer (A-0), there will be no reaction sites with the crosslinking agent (C) described below, so the addition will be carried out only on the side chains. Only part of the hydroxyl group. Specifically, when the side chain hydroxy group is 100 mol %, it is preferable that 5.0 to 99 mol % is subjected to the addition reaction. The method for adding the isocyanato group-containing ethylenically unsaturated compound (a) is not particularly limited, and methods known in the technical field of this specification can be used. (Meth)acrylic resin (A) has ethylenically unsaturated groups in its side chains, so compared to (meth)acrylic copolymers with ethylenically unsaturated groups introduced at the ends, the molecular chain between crosslinking points is The length is relatively short, and the adhesive force can be greatly reduced after UV irradiation. Therefore, a pressure-sensitive adhesive sheet using (meth)acrylic resin (A) has excellent releasability from an adherend. In addition, since the (meth)acrylic resin (A) has an appropriate molecular weight distribution, the adhesive composition manufactured using the methacrylic resin (A) has excellent adhesion to the adhesive layer. have Therefore, the adhesive composition manufactured using the (meth)acrylic resin (A) is suitably used in the adhesive layer of the dicing/die-bonding integrated film.
　（メタ）アクリル樹脂（Ａ）の分子量分布（Ｍｗ／Ｍｎ）は、好ましくは２．４以上、より好ましくは２．５以上、さらに好ましくは３．０以上である。（メタ）アクリル樹脂（Ａ）の分子量分布は、好ましくは１０．０以下、より好ましくは６．０以下、さらに好ましくは５．８以下、いっそう好ましくは５．６以下である。これらの下限値と上限値の組み合わせは、いかなる組み合わせでもよい。
　（メタ）アクリル樹脂（Ａ）の分子量分布は、好ましくは２．４～１０．０、より好ましくは２．４～６．０、さらに好ましくは２．５～５．８、いっそう好ましくは３．０～５．６である。分子量分布が２．４以上であると、（メタ）アクリル樹脂（Ａ）を含む粘着剤組成物の濡れ性が向上し、被着体、特に接着剤層に対する密着性が良好である。分子量分布が１０．０以下であると、高分子量の領域の（メタ）アクリル樹脂（Ａ）が適正範囲に収まることで粘着剤組成物の粘度コントロールが容易であり、低分子量の領域の（メタ）アクリル樹脂（Ａ）が適正範囲に収まることで被着体から粘着シートを剥離した際の糊残りが抑制される。 The molecular weight distribution (Mw/Mn) of the (meth)acrylic resin (A) is preferably 2.4 or more, more preferably 2.5 or more, and still more preferably 3.0 or more. The molecular weight distribution of the (meth)acrylic resin (A) is preferably 10.0 or less, more preferably 6.0 or less, still more preferably 5.8 or less, even more preferably 5.6 or less. Any combination of these lower limit values and upper limit values may be used.
The molecular weight distribution of the (meth)acrylic resin (A) is preferably 2.4 to 10.0, more preferably 2.4 to 6.0, still more preferably 2.5 to 5.8, even more preferably 3. It is 0 to 5.6. When the molecular weight distribution is 2.4 or more, the wettability of the pressure-sensitive adhesive composition containing the (meth)acrylic resin (A) is improved, and the adhesiveness to the adherend, especially the adhesive layer, is good. When the molecular weight distribution is 10.0 or less, the (meth)acrylic resin (A) in the high molecular weight region falls within an appropriate range, making it easy to control the viscosity of the adhesive composition, and the (meth)acrylic resin (A) in the low molecular weight region falls within an appropriate range. ) By keeping the acrylic resin (A) within an appropriate range, adhesive residue is suppressed when the adhesive sheet is peeled off from the adherend.
　（メタ）アクリル樹脂（Ａ）の重量平均分子量（Ｍｗ）は、好ましくは１００,０００以上、より好ましくは１５０,０００以上、さらに好ましくは２００,０００以上、いっそう好ましくは３００,０００以上である。（メタ）アクリル樹脂（Ａ）の重量平均分子量は、好ましくは８００,０００以下、より好ましくは７００,０００以下、さらに好ましくは６５０,０００以下である。これらの下限値と上限値の組み合わせは、いかなる組み合わせでもよい。
　（メタ）アクリル樹脂（Ａ）の重量平均分子量（Ｍｗ）は、好ましくは１００,０００～８００,０００であり、より好ましくは１５０,０００～７００,０００であり、さらに好ましくは２００,０００～６５０,０００であり、いっそう好ましくは３００,０００～６５０,０００である。重量平均分子量が１００,０００以上であると、ＵＶ照射後の剥離性が向上する。重量平均分子量が８００,０００以下であると、（メタ）アクリル樹脂（Ａ）を含む粘着剤組成物の粘度を適度に抑えることができ、粘着剤組成物の作業性を高めることができる。 The weight average molecular weight (Mw) of the (meth)acrylic resin (A) is preferably 100,000 or more, more preferably 150,000 or more, still more preferably 200,000 or more, even more preferably 300,000 or more. The weight average molecular weight of the (meth)acrylic resin (A) is preferably 800,000 or less, more preferably 700,000 or less, even more preferably 650,000 or less. Any combination of these lower limit values and upper limit values may be used.
The weight average molecular weight (Mw) of the (meth)acrylic resin (A) is preferably 100,000 to 800,000, more preferably 150,000 to 700,000, and even more preferably 200,000 to 650. ,000, more preferably 300,000 to 650,000. When the weight average molecular weight is 100,000 or more, the peelability after UV irradiation is improved. When the weight average molecular weight is 800,000 or less, the viscosity of the adhesive composition containing the (meth)acrylic resin (A) can be appropriately suppressed, and the workability of the adhesive composition can be improved.
　（メタ）アクリル樹脂（Ａ）のエチレン性不飽和基当量は、好ましくは１００～３，０００ｇ／ｍｏｌであり、より好ましくは３００～２，５００ｇ／ｍｏｌであり、さらに好ましくは５００～２，０００ｇ／ｍｏｌである。上記範囲内であれば、ＵＶ照射時の粘着剤組成物の架橋量が十分であり、（メタ）アクリル樹脂（Ａ）を用いて製造された粘着シートを被着体から剥離する際の優れた剥離性、及び小片化した素子の優れたピックアップ性が得られる。本明細書において、（メタ）アクリル樹脂（Ａ）のエチレン性不飽和基当量とは、エチレン性不飽和結合のモル数当たりの（メタ）アクリル樹脂（Ａ）の質量である。一実施形態における（メタ）アクリル樹脂（Ａ）のエチレン性不飽和基当量は、（メタ）アクリル樹脂（Ａ）の製造に使用した各原料が１００％反応したと仮定して、仕込み量から算出した計算値である。（メタ）アクリル樹脂（Ａ）のエチレン性不飽和基当量は、（メタ）アクリル樹脂（Ａ）へのハロゲンの結合量から算出してもよい。（メタ）アクリル樹脂（Ａ）へのハロゲンの結合量は、ＪＩＳ　Ｋ　００７０：１９９２に準じて評価できる。 The ethylenically unsaturated group equivalent of the (meth)acrylic resin (A) is preferably 100 to 3,000 g/mol, more preferably 300 to 2,500 g/mol, even more preferably 500 to 2,000 g /mol. Within the above range, the amount of crosslinking of the adhesive composition during UV irradiation is sufficient, and the adhesive sheet produced using the (meth)acrylic resin (A) has excellent properties when peeled from the adherend. Excellent peelability and pick-up of small pieces of elements can be obtained. In this specification, the ethylenically unsaturated group equivalent of the (meth)acrylic resin (A) is the mass of the (meth)acrylic resin (A) per mole of ethylenically unsaturated bonds. The ethylenically unsaturated group equivalent of the (meth)acrylic resin (A) in one embodiment is calculated from the amount charged, assuming that each raw material used in the production of the (meth)acrylic resin (A) has reacted 100%. This is the calculated value. The ethylenically unsaturated group equivalent of the (meth)acrylic resin (A) may be calculated from the amount of halogen bonded to the (meth)acrylic resin (A). The amount of halogen bonded to the (meth)acrylic resin (A) can be evaluated according to JIS K 0070:1992.
　（メタ）アクリル樹脂（Ａ）のガラス転移温度（Ｔｇ）は、好ましくは－８０℃～０℃であり、より好ましくは－７０℃～－１０℃であり、さらに好ましくは－６０℃～－３０℃である。ガラス転移温度（Ｔｇ）が－８０℃以上であると、粘着剤組成物の凝集力が高まり、糊残りが抑制される。ガラス転移温度（Ｔｇ）が０℃以下であると、被着体加工時の十分な固定性及び接着強度が得られる。 The glass transition temperature (Tg) of the (meth)acrylic resin (A) is preferably -80°C to 0°C, more preferably -70°C to -10°C, even more preferably -60°C to -30°C. It is ℃. When the glass transition temperature (Tg) is −80° C. or higher, the cohesive force of the pressure-sensitive adhesive composition increases and adhesive residue is suppressed. When the glass transition temperature (Tg) is 0° C. or less, sufficient fixing properties and adhesive strength can be obtained during processing of adherends.
　原料モノマー群（Ｍ）がカルボキシ基含有単量体（ｍ－３）を含有する場合、（メタ）アクリル樹脂（Ａ）の酸価は、好ましくは０．５～１００ｍｇＫＯＨ／ｇであり、より好ましくは１．０～５０ｍｇＫＯＨ／ｇであり、さらに好ましくは３．０～２５ｍｇＫＯＨ／ｇである。酸価が０．５ｍｇＫＯＨ／ｇ以上であると、架橋剤（Ｃ）としてポリエポキシ化合物を用いた場合に十分な架橋量が確保でき、粘着剤層の凝集力を十分に確保することができる。酸価が１００ｍｇＫＯＨ／ｇ以下であると、粘着剤組成物の保存安定性が良好である。本明細書において酸価は、ＪＩＳ　Ｋ　００７０：１９９２に従って測定した値である。 When the raw material monomer group (M) contains a carboxyl group-containing monomer (m-3), the acid value of the (meth)acrylic resin (A) is preferably 0.5 to 100 mgKOH/g, more preferably is 1.0 to 50 mgKOH/g, more preferably 3.0 to 25 mgKOH/g. When the acid value is 0.5 mgKOH/g or more, a sufficient amount of crosslinking can be ensured when a polyepoxy compound is used as the crosslinking agent (C), and a sufficient cohesive force of the adhesive layer can be ensured. When the acid value is 100 mgKOH/g or less, the storage stability of the adhesive composition is good. In this specification, the acid value is a value measured according to JIS K 0070:1992.
（イソシアナト基含有エチレン性不飽和化合物（ａ））
　イソシアナト基含有エチレン性不飽和化合物（ａ）は、ヒドロキシ基とカルボキシ基を有さず、イソシアナト基とエチレン性不飽和基を有する化合物であれば、特に限定されない。具体的には、２－イソシアナトエチル（メタ）アクリレート、２－イソシアナトプロピル（メタ）アクリレート、３－イソシアナトプロピル（メタ）アクリレート、２－イソシアナト－１－メチルエチル（メタ）アクリレート、２－イソシアナト－１，１－ジメチルエチル（メタ）アクリレート、４－イソシアナトシクロヘキシル（メタ）アクリレート等の（メタ）アクリロイルオキシアルキルイソシアネート；２－（２－イソシアナトエチルオキシ）エチル（メタ）アクリレート；１，１－（ビス（メタ）アクリロイルオキシメチル）エチルイソシアネートなどが挙げられる。中でも、（メタ）アクリル樹脂（Ａ）の合成のし易さの観点から、（メタ）アクリロイルオキシアルキルイソシアネートが好ましく、２－イソシアナトエチル（メタ）アクリレートがより好ましい。 (Isocyanato group-containing ethylenically unsaturated compound (a))
The isocyanato group-containing ethylenically unsaturated compound (a) is not particularly limited as long as it is a compound that does not have a hydroxyl group or a carboxy group and has an isocyanato group and an ethylenically unsaturated group. Specifically, 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, 2-isocyanato-1-methylethyl (meth)acrylate, 2- (Meth)acryloyloxyalkyl isocyanate such as isocyanato-1,1-dimethylethyl (meth)acrylate, 4-isocyanatocyclohexyl (meth)acrylate; 2-(2-isocyanatoethyloxy)ethyl (meth)acrylate; 1, Examples include 1-(bis(meth)acryloyloxymethyl)ethyl isocyanate. Among these, from the viewpoint of ease of synthesis of the (meth)acrylic resin (A), (meth)acryloyloxyalkyl isocyanate is preferred, and 2-isocyanatoethyl (meth)acrylate is more preferred.
　イソシアナト基含有エチレン性不飽和化合物（ａ）の含有量は、原料モノマー群（Ｍ）１００モルに対して、好ましくは０．２５モル以上、より好ましくは０．５０モル以上、さらに好ましくは１．０以上である。イソシアナト基含有エチレン性不飽和化合物（ａ）の含有量は、好ましくは４９モルで以下、より好ましくは４７モル以下、さらに好ましくは４５モル以下である。これらの下限値と上限値の組み合わせは、いかなる組み合わせでもよい。
　イソシアナト基含有エチレン性不飽和化合物（ａ）の含有量は、原料モノマー群（Ｍ）１００モルに対して、好ましくは０．２５～４９モルであり、より好ましくは０．５０～４７モルであり、さらに好ましくは１．０～４５モルである。イソシアナト基含有エチレン性不飽和化合物（ａ）の含有量が０．２５モル以上であると、十分量のエチレン性不飽和基が（メタ）アクリル樹脂（Ａ）に導入され、ＵＶ照射後に粘着シートを被着体から剥離する際のより優れた剥離性を得ることができる。イソシアナト基含有エチレン性不飽和化合物（ａ）の含有量が４９モル以下であると、（メタ）アクリル樹脂（Ａ）のヒドロキシ基の含有量を十分に確保することができ、粘着剤層の優れた凝集力が得られる。加えて、未反応のイソシアナト基含有エチレン性不飽和化合物（ａ）の量を低減できるため、糊残りの少ない粘着シートが得られる。 The content of the isocyanato group-containing ethylenically unsaturated compound (a) is preferably 0.25 mol or more, more preferably 0.50 mol or more, still more preferably 1. It is 0 or more. The content of the isocyanato group-containing ethylenically unsaturated compound (a) is preferably 49 mol or less, more preferably 47 mol or less, still more preferably 45 mol or less. Any combination of these lower limit values and upper limit values may be used.
The content of the isocyanato group-containing ethylenically unsaturated compound (a) is preferably 0.25 to 49 mol, more preferably 0.50 to 47 mol, per 100 mol of the raw material monomer group (M). , more preferably 1.0 to 45 mol. When the content of the isocyanato group-containing ethylenically unsaturated compound (a) is 0.25 mol or more, a sufficient amount of ethylenically unsaturated groups will be introduced into the (meth)acrylic resin (A), and the pressure-sensitive adhesive sheet will be formed after UV irradiation. It is possible to obtain better releasability when peeling off from an adherend. When the content of the isocyanato group-containing ethylenically unsaturated compound (a) is 49 mol or less, a sufficient content of hydroxyl groups in the (meth)acrylic resin (A) can be ensured, resulting in an excellent adhesive layer. A cohesive force can be obtained. In addition, since the amount of unreacted isocyanato group-containing ethylenically unsaturated compound (a) can be reduced, a pressure-sensitive adhesive sheet with less adhesive residue can be obtained.
（触媒）
　工程（ｉｉ）における付加反応では、必要に応じて、公知の触媒を使用することができる。触媒としては、例えば、ジブチル錫ジラウレート、チタンジイソプロポキシビス（エチルアセトアセテート）、テトラキス(２，４－ペンタンジオナト)ジルコニウム、ビスマストリス（２－エチルヘキサノエート）等のウレタン化触媒を用いることができる。 (catalyst)
In the addition reaction in step (ii), a known catalyst can be used as necessary. As a catalyst, for example, a urethanization catalyst such as dibutyltin dilaurate, titanium diisopropoxy bis(ethyl acetoacetate), tetrakis(2,4-pentanedionato)zirconium, bismuth tris(2-ethylhexanoate) is used. be able to.
　工程（ｉｉ）において触媒を使用する場合、触媒の使用量は、共重合体（Ａ－０）とイソシアナト基含有エチレン性不飽和化合物（ａ）との合計１００質量部に対して、０．０１～１０質量部が好ましく、０．０２～５質量部がより好ましく、０．０３～１質量部がさらに好ましい。 When using a catalyst in step (ii), the amount of the catalyst used is 0.01 parts by mass based on the total of 100 parts by mass of the copolymer (A-0) and the isocyanato group-containing ethylenically unsaturated compound (a). It is preferably from 10 parts by weight, more preferably from 0.02 to 5 parts by weight, even more preferably from 0.03 to 1 part by weight.
（重合禁止剤）
　工程（ｉｉ）における付加反応では、必要に応じて、公知の重合禁止剤を使用することができる。重合禁止剤としては、公知のものを使用することができ、特に制限はされないが、例えば、４－メトキシフェノール、ヒドロキノン、メトキノン、２，６－ジ－ｔ－ブチルフェノール、２，２’－メチレンビス（４－メチル－６－ｔ－ブチルフェノール）、及びフェノチアジンが挙げられる。重合禁止剤は、単独で使用してもよいし、２種以上を組み合わせて使用してもよい。 (Polymerization inhibitor)
In the addition reaction in step (ii), a known polymerization inhibitor can be used as necessary. Known polymerization inhibitors can be used and are not particularly limited, but examples include 4-methoxyphenol, hydroquinone, methoquinone, 2,6-di-t-butylphenol, and 2,2'-methylenebis( (4-methyl-6-t-butylphenol) and phenothiazine. Polymerization inhibitors may be used alone or in combination of two or more.
　工程（ｉｉ）において重合禁止剤を使用する場合、重合禁止剤の使用量は、共重合体（Ａ－０）とイソシアナト基含有エチレン性不飽和化合物（ａ）との合計１００質量部に対して、０．００５～５質量部が好ましく、０．０３～３質量部がより好ましく、０．０５～１．５質量部がさらに好ましい。重合禁止剤の使用量が０．００５質量部以上であれば、付加反応時のゲル化を防ぐことができる。一方、重合禁止剤の使用量が５質量部以下であれば、ＵＶ照射時の（メタ）アクリル樹脂（Ａ）の十分な露光感度が得られる。 When a polymerization inhibitor is used in step (ii), the amount of the polymerization inhibitor used is based on the total of 100 parts by mass of the copolymer (A-0) and the isocyanato group-containing ethylenically unsaturated compound (a). , preferably 0.005 to 5 parts by weight, more preferably 0.03 to 3 parts by weight, and even more preferably 0.05 to 1.5 parts by weight. If the amount of the polymerization inhibitor used is 0.005 parts by mass or more, gelation during the addition reaction can be prevented. On the other hand, if the amount of the polymerization inhibitor used is 5 parts by mass or less, sufficient exposure sensitivity of the (meth)acrylic resin (A) upon UV irradiation can be obtained.
（反応条件）
　付加反応の温度は、２５℃～１３０℃であることが好ましく、４０℃～１２０℃であることが特に好ましい。付加反応の温度が２５℃以上であると、十分な反応速度を得ることができる。付加反応の温度が１３０℃以下であると、熱によるラジカル重合によって二重結合部が架橋し、ゲル化物が生じることを防止できる。 (Reaction conditions)
The temperature of the addition reaction is preferably 25°C to 130°C, particularly preferably 40°C to 120°C. When the temperature of the addition reaction is 25° C. or higher, a sufficient reaction rate can be obtained. When the temperature of the addition reaction is 130° C. or lower, it is possible to prevent double bonds from being crosslinked due to radical polymerization due to heat and from forming a gelled product.
　付加反応時には、重合禁止効果のあるガスを反応系中に導入してもよい。重合禁止効果のあるガスを反応系中に導入することにより、付加反応時のゲル化を防ぐことができる。 During the addition reaction, a gas having a polymerization inhibiting effect may be introduced into the reaction system. By introducing a gas having a polymerization inhibiting effect into the reaction system, gelation during the addition reaction can be prevented.
　重合禁止効果のあるガスとしては、系内物質の爆発範囲に入らない程度の酸素を含むガス、例えば、空気などが挙げられる。 Examples of gases that have a polymerization inhibiting effect include gases that contain oxygen to an extent that does not fall within the explosive range of substances in the system, such as air.
　重合禁止効果のあるガスと重合禁止剤とを併用すると、使用する重合禁止剤の量を低減したり、重合禁止効果を高めたりできるためより好ましい。 It is more preferable to use a polymerization inhibitor together with a gas that has a polymerization inhibiting effect because the amount of polymerization inhibitor used can be reduced and the polymerization inhibiting effect can be enhanced.
［粘着剤組成物の製造方法］
　粘着剤組成物は、（メタ）アクリル樹脂（Ａ）と、光重合開始剤（Ｂ）と、架橋剤（Ｃ）と、必要に応じて添加されるその他の成分とを混合する工程（ｉｉｉ）を含む方法により製造することができる。（メタ）アクリル樹脂（Ａ）を含む粘着剤組成物は、再剥離型粘着シート、特に、ダイシング・ダイボンド一体型フィルムに好適に用いられる。 [Method for producing adhesive composition]
The adhesive composition is prepared by mixing the (meth)acrylic resin (A), the photopolymerization initiator (B), the crosslinking agent (C), and other components added as necessary (iii). It can be manufactured by a method including. The pressure-sensitive adhesive composition containing the (meth)acrylic resin (A) is suitably used for removable pressure-sensitive adhesive sheets, particularly for dicing and die-bonding integrated films.
　粘着剤組成物に含まれる各成分を混合する方法は、特に限定されるものではない。混合は、例えば、ホモディスパー、パドル翼等の攪拌翼を取り付けた攪拌装置を用いて行うことができる。 The method of mixing each component contained in the adhesive composition is not particularly limited. Mixing can be performed using, for example, a stirring device equipped with a stirring blade such as a homodisper or a paddle blade.
＜光重合開始剤（Ｂ）＞
　光重合開始剤（Ｂ）としては、例えば、ベンゾフェノン、ベンジル、ベンゾイン、ω－ブロモアセトフェノン、クロロアセトン、アセトフェノン、２，２－ジエトキシアセトフェノン、２，２－ジメトキシ－２－フェニルアセトフェノン、ｐ－ジメチルアミノアセトフェノン、ｐ－ジメチルアミノプロピオフェノン、２－クロロベンゾフェノン、４，４’－ジクロロベンゾフェノン、４，４’－ビスジエチルアミノベンゾフェノン、ミヒラーケトン、ベンゾインメチルエーテル、ベンゾインイソブチルエーテル、ベンゾイン－ｎ－ブチルエーテル、ベンジルメチルケタール、１－ヒドロキシシクロヘキシルフェニルケトン、２－ヒドロキシ－２－メチル－１－フェニル－プロパン－１－オン、１－（４－イソプロピルフェニル）－２－ヒドロキシ－２－メチルプロパン－１－オン、メチルベンゾイルホルメート、４’－ジメチルアミノアセトフェノン、２－メチル－１－［４－（メチルチオ）フェニル］－２－モルフォリノプロパン－１－オン等のカルボニル系光重合開始剤が挙げられる。 <Photopolymerization initiator (B)>
Examples of the photopolymerization initiator (B) include benzophenone, benzyl, benzoin, ω-bromoacetophenone, chloroacetone, acetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, p-dimethyl Aminoacetophenone, p-dimethylaminopropiophenone, 2-chlorobenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone, Michler's ketone, benzoin methyl ether, benzoin isobutyl ether, benzoin-n-butyl ether, benzyl Methyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, Examples include carbonyl photopolymerization initiators such as methylbenzoylformate, 4'-dimethylaminoacetophenone, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one.
　光重合開始剤（Ｂ）としては、例えば、ジフェニルジスルフィド、ジベンジルジスルフィド、テトラエチルチウラムジスルフィド、テトラメチルアンモニウムモノスルフィド等のスルフィド系光重合開始剤；２，４，６－トリメチルベンゾイルジフェニルホスフィンオキサイド、２，４，６－トリメチルベンゾイルフェニルエトキシホスフィンオキサイド等のアシルホスフィンオキサイド；ベンゾキノン、アントラキノン等のキノン系光重合開始剤；スルホクロリド系光重合開始剤；及びチオキサントン、２－クロロチオキサントン、２－メチルチオキサントン等のチオキサントン系光重合開始剤も挙げられる。 Examples of the photopolymerization initiator (B) include sulfide photopolymerization initiators such as diphenyl disulfide, dibenzyl disulfide, tetraethylthiuram disulfide, and tetramethylammonium monosulfide; 2,4,6-trimethylbenzoyldiphenylphosphine oxide; , acylphosphine oxides such as 4,6-trimethylbenzoylphenylethoxyphosphine oxide; quinone-based photopolymerization initiators such as benzoquinone and anthraquinone; sulfochloride-based photopolymerization initiators; and thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, etc. Also included are thioxanthone photopolymerization initiators.
　これらの光重合開始剤（Ｂ）の中でも、粘着剤組成物への溶解性の点から、カルボニル系光重合開始剤、及びアシルホスフィンオキサイドが好ましく、１－ヒドロキシシクロヘキシルフェニルケトン、及び２，４，６－トリメチルベンゾイルジフェニルホスフィンオキサイドから選択される少なくとも一種を用いることがより好ましい。 Among these photoinitiators (B), carbonyl photoinitiators and acylphosphine oxides are preferred from the viewpoint of solubility in the adhesive composition, and 1-hydroxycyclohexylphenyl ketone and 2,4, It is more preferable to use at least one selected from 6-trimethylbenzoyldiphenylphosphine oxide.
　光重合開始剤（Ｂ）は、単独で使用してもよいし、２種以上を組み合わせて使用してもよい。 The photopolymerization initiator (B) may be used alone or in combination of two or more types.
　光重合開始剤（Ｂ）は、（メタ）アクリル樹脂（Ａ）１００質量部に対して、０．１～５．０質量部であることが好ましく、０．５～２．０質量部であることがより好ましい。（メタ）アクリル樹脂（Ａ）１００質量部に対する光重合開始剤（Ｂ）の含有量が０．１質量部以上であると、ＵＶ照射時に十分に速い硬化速度で粘着剤組成物を硬化させることができるため、ＵＶ照射後の粘着剤層の粘着力を十分に小さくすることができる。（メタ）アクリル樹脂（Ａ）１００質量部に対する光重合開始剤（Ｂ）の含有量が５．０質量部以下であると、粘着剤組成物を含む粘着剤層を有する粘着シートを、被着体に貼り付けた後に剥離した場合に、粘着剤層が被着体に残存しにくくなる。（メタ）アクリル樹脂（Ａ）１００質量部に対する光重合開始剤（Ｂ）の含有量が５．０質量部を超えても、光重合開始剤（Ｂ）の含有量に見合う効果が見られないため、含有量を５．０質量部以下とすることで、経済的に粘着剤組成物を製造することができる。 The photopolymerization initiator (B) is preferably 0.1 to 5.0 parts by mass, and 0.5 to 2.0 parts by mass, based on 100 parts by mass of the (meth)acrylic resin (A). It is more preferable. When the content of the photopolymerization initiator (B) is 0.1 parts by mass or more based on 100 parts by mass of the (meth)acrylic resin (A), the adhesive composition can be cured at a sufficiently fast curing rate during UV irradiation. Therefore, the adhesive force of the adhesive layer after UV irradiation can be sufficiently reduced. When the content of the photopolymerization initiator (B) is 5.0 parts by mass or less with respect to 100 parts by mass of the (meth)acrylic resin (A), the adhesive sheet having the adhesive layer containing the adhesive composition cannot be adhered. When the adhesive layer is peeled off after being attached to the body, the adhesive layer is less likely to remain on the adherend. Even if the content of the photopolymerization initiator (B) exceeds 5.0 parts by mass with respect to 100 parts by mass of the (meth)acrylic resin (A), no effect commensurate with the content of the photopolymerization initiator (B) is observed. Therefore, by setting the content to 5.0 parts by mass or less, the adhesive composition can be economically produced.
＜架橋剤（Ｃ）＞
　架橋剤（Ｃ）を混合することにより、ＵＶ照射前の粘着力とＵＶ照射後の粘着力とのバランスが良好な粘着剤組成物を得ることができる。架橋剤（Ｃ）はエチレン性不飽和結合を有さない化合物であって、（メタ）アクリル樹脂（Ａ）に含まれるヒドロキシ基及び／又は任意に含まれる官能基であるカルボキシ基と反応する官能基を２個以上有する化合物である。 <Crosslinking agent (C)>
By mixing the crosslinking agent (C), it is possible to obtain a pressure-sensitive adhesive composition with a good balance between the adhesive strength before UV irradiation and the adhesive strength after UV irradiation. The crosslinking agent (C) is a compound having no ethylenically unsaturated bond, and is a functional compound that reacts with the hydroxy group contained in the (meth)acrylic resin (A) and/or the optionally contained functional group carboxyl group. A compound having two or more groups.
　架橋剤（Ｃ）としては、特に限定されないが、ヒドロキシ基に対して反応性を有する官能基を２つ以上有する化合物が好ましい。（メタ）アクリル樹脂（Ａ）がカルボキシ基を有する場合には、カルボキシ基に対して反応性を有する官能基を２つ以上有する化合物を用いてもよい。ヒドロキシ基に対して反応性を有する官能基としては、イソシアナト基、エポキシ基、カルボキシ基、酸無水物基、アジリジニル基等が挙げられるが、反応性の観点でイソシアナト基、及びエポキシ基が好ましく、特にイソシアナト基が好ましい。カルボキシ基に対して反応性を有する官能基としては、エポキシ基、ヒドロキシ基、アジリジニル等が挙げられるが、反応性の観点でエポキシ基、及びアジリジニル基が好ましい。 The crosslinking agent (C) is not particularly limited, but a compound having two or more functional groups reactive with hydroxyl groups is preferred. When the (meth)acrylic resin (A) has a carboxy group, a compound having two or more functional groups reactive with the carboxy group may be used. Examples of the functional group having reactivity with a hydroxy group include an isocyanato group, an epoxy group, a carboxy group, an acid anhydride group, an aziridinyl group, and from the viewpoint of reactivity, an isocyanato group and an epoxy group are preferable. Particularly preferred is an isocyanato group. Examples of the functional group having reactivity with a carboxyl group include an epoxy group, a hydroxy group, and an aziridinyl group. From the viewpoint of reactivity, an epoxy group and an aziridinyl group are preferable.
　架橋剤（Ｃ）としては、例えば、２，４－トリレンジイソシアネート、２，６－トリレンジイソシアネート、水素化トリレンジイソシアネート、１，３－キシリレンジイソシアネート、１，４－キシリレンジイソシアネート、ジフェニルメタン－４，４’－ジイソシアネート、イソホロンジイソシアネート、１，３－ビス（イソシアナトメチル）シクロヘキサン、ヘキサメチレンジイソシアネートのイソシアヌレート体、テトラメチルキシリレンジイソシアネート、１，５－ナフタレンジイソシアネート、トリメチロールプロパンのトリレンジイソシアネート付加物、トリメチロールプロパンのキシリレンジイソシアネート付加物、トリフェニルメタントリイソシアネート、メチレンビス（４－フェニルメタン）トリイソシアネート等のポリイソシアネート；１，３－ビス（Ｎ，Ｎ’－ジグリシジルアミノメチル）シクロヘキサン、ビスフェノールＡ－エピクロルヒドリン型のエポキシ樹脂、Ｎ，Ｎ’－［１，３－フェニレンビス（メチレン）］ビス［ビス（オキシラン－２－イルメチル）アミン］、エチレングリコールジグリシジルエーテル、ポリエチレングリコールジグリシジルエーテル、グリセリンジグリシジルエーテル、グリセリントリグリシジルエーテル、１，６－ヘキサンジオールジグリシジルエーテル、トリメチロールプロパントリグリシジルエーテル、ソルビトールポリグリシジルエーテル、ポリグリセロールポリグリシジルエーテル、ペンタエリスリトールポリグリシジルエーテル、ジグリセロールポリグリシジルエーテル等のポリエポキシ化合物；テトラメチロールメタン－トリ－β－アジリジニルプロピオネート、トリメチロールプロパン－トリ－β－アジリジニルプロピオネート、Ｎ，Ｎ’－ジフェニルメタン－４，４’－ビス（１－アジリジンカルボキシアミド）、Ｎ，Ｎ’－ヘキサメチレン－１，６－ビス（１－アジリジンカルボキシアミド）等のアジリジン化合物；ヘキサメトキシメチルメラミン、ヘキサエトキシメチルメラミン、ヘキサプロポキシメチルメラミン、ヘキサブトキシメチルメラミン、ヘキサペンチルオキシメチルメラミン、ヘキサヘキシルオキシメチルメラミン等のメラミン化合物；エチレングリコール－ビス－［３－（２－アジリジニル）プロピオネート］、トリメチロールプロパン－トリス［３－（２－アジリジニル）プロピオネート］、トリメチロールプロパン－トリス［３－（１－アジリジニル）プロピオネート］、トリメチロールプロパン－トリス［３－（２－メチル－１－アジリジニル）プロピオネート］、テトラメチロールメタン－トリス［３－（２－アジリジニル）プロピオネート］、ペンタエリスリトール－トリス［３－（１－アジリジニル）プロピオネート］、Ｎ，Ｎ'－ジフェニルメタン－４，４'－ビス（１－アジリジンカルボキシアミド）、Ｎ，Ｎ'－ヘキサメチレン－１，６－ビス（１－アジリジンカルボキシアミド）等のアジリジニル化合物などが挙げられる。 Examples of the crosslinking agent (C) include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hydrogenated tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane- 4,4'-diisocyanate, isophorone diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, isocyanurate of hexamethylene diisocyanate, tetramethylxylylene diisocyanate, 1,5-naphthalene diisocyanate, tolylene diisocyanate of trimethylolpropane Adducts, polyisocyanates such as xylylene diisocyanate adducts of trimethylolpropane, triphenylmethane triisocyanate, methylenebis(4-phenylmethane)triisocyanate; 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane , bisphenol A-epichlorohydrin type epoxy resin, N,N'-[1,3-phenylenebis(methylene)]bis[bis(oxiran-2-ylmethyl)amine], ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether , glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether Polyepoxy compounds such as tetramethylolmethane-tri-β-aziridinylpropionate, trimethylolpropane-tri-β-aziridinylpropionate, N,N'-diphenylmethane-4,4'-bis( Aziridine compounds such as N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide); hexamethoxymethylmelamine, hexaethoxymethylmelamine, hexapropoxymethylmelamine, hexabutoxymethyl Melamine compounds such as melamine, hexapentyloxymethylmelamine, hexahexyloxymethylmelamine; ethylene glycol-bis-[3-(2-aziridinyl)propionate], trimethylolpropane-tris[3-(2-aziridinyl)propionate], Trimethylolpropane-tris[3-(1-aziridinyl)propionate], trimethylolpropane-tris[3-(2-methyl-1-aziridinyl)propionate], tetramethylolmethane-tris[3-(2-aziridinyl)propionate] ], pentaerythritol-tris[3-(1-aziridinyl)propionate], N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), N,N'-hexamethylene-1,6- Examples include aziridinyl compounds such as bis(1-aziridinecarboxamide).
　これらの架橋剤（Ｃ）の中でも、（メタ）アクリル樹脂（Ａ）との反応性が良好であることから、ポリイソシアネート、及びポリエポキシ化合物からなる群から選択される少なくとも一種を用いることが好ましく、ポリイソシアネートを用いることがより好ましい。 Among these crosslinking agents (C), it is preferable to use at least one selected from the group consisting of polyisocyanates and polyepoxy compounds because of its good reactivity with the (meth)acrylic resin (A). , it is more preferable to use polyisocyanate.
　架橋剤（Ｃ）は、単独で使用してもよいし、２種以上を組み合わせて使用してもよい。 The crosslinking agent (C) may be used alone or in combination of two or more.
　架橋剤（Ｃ）は、（メタ）アクリル樹脂（Ａ）１００質量部に対して、０．１～３０質量部であることが好ましく、０．１～２０質量部であることがより好ましく、０．１～１０質量部であることが更に好ましく、０．１～５質量部であることがいっそう好ましい。（メタ）アクリル樹脂（Ａ）１００質量部に対する架橋剤（Ｃ）の含有量が０．１質量部以上であると、ＵＶ照射時に粘着剤組成物に三次元架橋構造が十分に形成されるため、ＵＶ照射後の粘着剤組成物の粘着力を十分に小さくすることができる。（メタ）アクリル樹脂（Ａ）１００質量部に対する架橋剤（Ｃ）の含有量が３０質量部以下であると、ＵＶ照射前の粘着剤組成物の粘着力が良好である。 The crosslinking agent (C) is preferably 0.1 to 30 parts by weight, more preferably 0.1 to 20 parts by weight, based on 100 parts by weight of the (meth)acrylic resin (A), and The amount is more preferably .1 to 10 parts by weight, and even more preferably 0.1 to 5 parts by weight. When the content of the crosslinking agent (C) is 0.1 parts by mass or more based on 100 parts by mass of the (meth)acrylic resin (A), a three-dimensional crosslinked structure is sufficiently formed in the adhesive composition during UV irradiation. , the adhesive force of the adhesive composition after UV irradiation can be sufficiently reduced. When the content of the crosslinking agent (C) is 30 parts by mass or less with respect to 100 parts by mass of the (meth)acrylic resin (A), the adhesive strength of the adhesive composition before UV irradiation is good.
（他の成分）
　粘着剤組成物の製造方法では、必要に応じて、（メタ）アクリル樹脂（Ａ）、光重合開始剤（Ｂ）、及び架橋剤（Ｃ）以外の他の成分を混合してもよい。他の成分としては、例えば、粘着付与剤、溶媒、及び各種添加剤が挙げられる。 (other ingredients)
In the method for producing an adhesive composition, other components than the (meth)acrylic resin (A), the photopolymerization initiator (B), and the crosslinking agent (C) may be mixed as necessary. Examples of other components include tackifiers, solvents, and various additives.
（粘着付与剤）
　粘着付与剤としては、従来公知のものを特に限定なく使用できる。粘着付与剤としては、例えば、テルペン系粘着付与樹脂、フェノール系粘着付与樹脂、ロジン系粘着付与樹脂、脂肪族系石油樹脂、芳香族系石油樹脂、共重合系石油樹脂、脂環族系石油樹脂、キシレン樹脂、エポキシ系粘着付与樹脂、ポリアミド系粘着付与樹脂、ケトン系粘着付与樹脂、及びエラストマー系粘着付与樹脂が挙げられる。これらの粘着付与剤は、単独で使用してもよいし、２種以上を組み合わせて使用してもよい。 (Tackifier)
As the tackifier, conventionally known tackifiers can be used without particular limitation. Examples of tackifiers include terpene-based tackifier resins, phenolic tackifier resins, rosin-based tackifier resins, aliphatic petroleum resins, aromatic petroleum resins, copolymer petroleum resins, and alicyclic petroleum resins. , xylene resin, epoxy tackifier resin, polyamide tackifier resin, ketone tackifier resin, and elastomer tackifier resin. These tackifiers may be used alone or in combination of two or more.
　粘着付与剤を混合する場合、その添加量は、（メタ）アクリル樹脂（Ａ）１００質量部に対して、３０質量部以下であることが好ましく、５～２０質量部であることがより好ましい。 When a tackifier is mixed, the amount added is preferably 30 parts by mass or less, more preferably 5 to 20 parts by mass, based on 100 parts by mass of the (meth)acrylic resin (A).
（溶媒）
　溶媒は、粘着剤組成物の粘度の調整を目的として粘着剤組成物を希釈するために用いることができる。例えば、粘着剤組成物を塗工する場合には、溶媒を用いて粘着剤組成物の粘度を適切な粘度にすることができる。 (solvent)
A solvent can be used to dilute the adhesive composition for the purpose of adjusting the viscosity of the adhesive composition. For example, when applying a pressure-sensitive adhesive composition, a solvent can be used to adjust the viscosity of the pressure-sensitive adhesive composition to an appropriate viscosity.
　溶媒としては、例えば、メチルエチルケトン、メチルイソブチルケトン、アセトン、酢酸エチル、酢酸プロピル、テトラヒドロフラン、ジオキサン、シクロヘキサノン、へキサン、トルエン、キシレン、ｎ－プロパノール、イソプロピルアルコール等の有機溶媒を用いることができる。これらの溶媒は、単独で使用してもよいし、２種以上を混合して使用してもよい。 As the solvent, for example, organic solvents such as methyl ethyl ketone, methyl isobutyl ketone, acetone, ethyl acetate, propyl acetate, tetrahydrofuran, dioxane, cyclohexanone, hexane, toluene, xylene, n-propanol, and isopropyl alcohol can be used. These solvents may be used alone or in combination of two or more.
（添加剤）
　添加剤としては、例えば、可塑剤、表面潤滑剤、レベリング剤、軟化剤、酸化防止剤、老化防止剤、光安定剤、紫外線吸収剤、重合禁止剤、ベンゾトリアゾール系等の光安定剤、リン酸エステル系及びその他の難燃剤、界面活性剤、並びに帯電防止剤が挙げられる。 (Additive)
Examples of additives include plasticizers, surface lubricants, leveling agents, softeners, antioxidants, anti-aging agents, light stabilizers, ultraviolet absorbers, polymerization inhibitors, benzotriazole-based light stabilizers, and phosphorus. Examples include acid ester and other flame retardants, surfactants, and antistatic agents.
［粘着シートの製造方法］
　粘着シートは、例えば、以下に示す方法により製造することができる。 [Method for manufacturing adhesive sheet]
The adhesive sheet can be manufactured, for example, by the method shown below.
　まず、粘着剤組成物を溶媒に溶解又は分散させた粘着剤溶液を調製する。粘着剤組成物を、そのまま粘着剤溶液として使用してもよい。 First, an adhesive solution is prepared by dissolving or dispersing the adhesive composition in a solvent. The adhesive composition may be used as it is as an adhesive solution.
　次に、基材上に粘着剤溶液を塗布し、溶媒を含む場合は加熱乾燥して溶媒を除去し、粘着剤層を形成する。その後、粘着剤層上に、必要に応じて剥離シートを貼り合せる。さらに、得られたシートを必要に応じて、オーブンで一定時間養生し、架橋構造を形成させることにより、粘着シートを得ることができる。 Next, an adhesive solution is applied onto the base material, and if it contains a solvent, the solvent is removed by heating and drying to form an adhesive layer. Thereafter, a release sheet is laminated on the adhesive layer, if necessary. Furthermore, a pressure-sensitive adhesive sheet can be obtained by curing the obtained sheet in an oven for a certain period of time to form a crosslinked structure, if necessary.
　粘着シートは、以下に示す方法により製造することもできる。剥離シート上に粘着剤溶液を塗布し、溶媒を含む場合は加熱乾燥して溶媒を除去し、粘着剤層を形成する。その後、粘着剤層を有する剥離シートを基材上に、粘着剤層側の面を基材に向けて設置し、基材上に粘着剤層を転写（移着）する。さらに、得られたシートを必要に応じて、オーブンで一定時間養生し、架橋構造を形成させることにより、粘着シートを得ることができる。 The adhesive sheet can also be manufactured by the method shown below. A pressure-sensitive adhesive solution is applied onto a release sheet, and if it contains a solvent, the solvent is removed by heating and drying to form a pressure-sensitive adhesive layer. Thereafter, a release sheet having an adhesive layer is placed on the base material with the adhesive layer side facing the base material, and the adhesive layer is transferred (transferred) onto the base material. Furthermore, a pressure-sensitive adhesive sheet can be obtained by curing the obtained sheet in an oven for a certain period of time to form a crosslinked structure, if necessary.
　上記の方法において、基材として接着剤層を有する基材を用いて、接着剤層に粘着剤組成物を塗布するか、接着剤層と粘着剤層とが向かい合うように積層することにより、ダイシング・ダイボンディング一体型フィルムを得ることができる。 In the above method, a base material having an adhesive layer is used as a base material, and the adhesive composition is applied to the adhesive layer, or the adhesive layer and the adhesive layer are laminated so as to face each other, thereby performing dicing. - A die bonding integrated film can be obtained.
　粘着剤溶液を基材上に（又は剥離シート上に）塗布する方法としては、公知の方法を用いることができる。具体的には、慣用のコーター、例えば、グラビヤロールコーター、リバースロールコーター、キスロールコーター、ディップロールコーター、バーコーター、ナイフコーター、スプレーコーター、コンマコーター、ダイレクトコーター等を用いて塗布する方法が挙げられる。 A known method can be used to apply the adhesive solution onto the base material (or onto the release sheet). Specifically, examples include coating methods using conventional coaters, such as gravure roll coater, reverse roll coater, kiss roll coater, dip roll coater, bar coater, knife coater, spray coater, comma coater, and direct coater. It will be done.
　塗布した粘着剤溶液を加熱乾燥する際の条件は、特に制限されないが、通常２５～１８０℃、好ましくは６０～１５０℃にて、通常１～２０分、好ましくは１～１０分加熱乾燥を行う。上記範囲で加熱乾燥を行うことにより、粘着剤溶液に含まれる溶媒を除去することができる。加熱乾燥後のシートをオーブンで一定時間養生する条件は、特に制限されないが、通常２５～１００℃、好ましくは３０～８０℃にて通常１～３０日間、好ましくは１～１４日間養生を行う。上記条件で養生を行うことにより、（メタ）アクリル樹脂（Ａ）を架橋剤（Ｃ）により架橋させて、粘着剤層のゲル分率を所望の範囲に調整することができる。 Conditions for heating and drying the applied adhesive solution are not particularly limited, but heating and drying is usually carried out at 25 to 180°C, preferably 60 to 150°C, for 1 to 20 minutes, preferably 1 to 10 minutes. . By performing heat drying in the above range, the solvent contained in the adhesive solution can be removed. The conditions for curing the heated and dried sheet in an oven for a certain period of time are not particularly limited, but the curing is usually carried out at 25 to 100°C, preferably 30 to 80°C, for 1 to 30 days, preferably 1 to 14 days. By curing under the above conditions, the (meth)acrylic resin (A) can be crosslinked with the crosslinking agent (C), and the gel fraction of the adhesive layer can be adjusted to a desired range.
［粘着シートの用途］
　粘着シートは、再剥離型粘着シートとして、例えば、電子部品を製造する際に用いることができる。再剥離型粘着シートは、具体的には、電子部品を製造する際の各工程において、被着体を固定し、種々の加工工程に付した後に、ＵＶ（紫外線）を照射して被着体から剥離する用途に用いられる。したがって、粘着シートは、半導体ウェハを加工する際のバックグラインドテープ、ダイシングテープ等として用いることができる。粘着シートは、極薄ガラス基板等の脆弱部材、ＦＰＣ基板等の反り易い部材の支持用テープ等として用いることもできる。特に、粘着シートは、接着剤層に対する優れた粘着性とＵＶ照射後の優れた剥離性を有するため、ダイシング・ダイボンディング一体型フィルムを製造する際に用いるダイシングテープに好適である。 [Applications of adhesive sheet]
The adhesive sheet can be used as a removable adhesive sheet, for example, when manufacturing electronic components. Specifically, a removable adhesive sheet is used to fix an adherend in each step of manufacturing electronic components, and after subjecting it to various processing steps, irradiates the adherend with UV (ultraviolet light). Used for peeling from. Therefore, the adhesive sheet can be used as a backgrind tape, dicing tape, etc. when processing semiconductor wafers. The adhesive sheet can also be used as a support tape for fragile members such as ultra-thin glass substrates and easily warped members such as FPC boards. In particular, the adhesive sheet has excellent adhesion to the adhesive layer and excellent releasability after UV irradiation, and is therefore suitable for a dicing tape used when manufacturing a dicing/die bonding integrated film.
　粘着シートをウェハのダイシングテープとして用いる場合、ダイシング工程を行う前に、複数の部品が形成されているウェハに粘着シートを貼り付ける。次に、ウェハを切断して、個々の部品に切り分け（ダイシングして）、素子小片（チップ）とする。その後、各素子小片上に貼り付けられている粘着シートにＵＶを照射する。このことにより、粘着シートの基材を通して粘着剤層にＵＶが照射され、粘着剤中の不飽和結合が三次元架橋構造を形成して硬化する。その結果、粘着剤層の粘着力が低下する。その後、各素子小片上から粘着シートを剥離する。 When using an adhesive sheet as a dicing tape for a wafer, the adhesive sheet is attached to the wafer on which multiple parts are formed before performing the dicing process. Next, the wafer is cut and diced into individual parts to form small element pieces (chips). Thereafter, UV irradiation is applied to the adhesive sheet pasted on each element piece. As a result, the adhesive layer is irradiated with UV light through the base material of the adhesive sheet, and the unsaturated bonds in the adhesive form a three-dimensional crosslinked structure and are cured. As a result, the adhesive force of the adhesive layer decreases. Thereafter, the adhesive sheet is peeled off from above each element piece.
　ＵＶ照射を行う際に使用される光源としては、例えば、高圧水銀灯、超高圧水銀灯、カーボンアーク灯、キセノン灯、メタルハライドランプ、ケミカルランプ、及びブラックライトが挙げられる。 Examples of light sources used when performing UV irradiation include high-pressure mercury lamps, ultra-high-pressure mercury lamps, carbon arc lamps, xenon lamps, metal halide lamps, chemical lamps, and black lights.
　粘着シートに照射するＵＶ照射量は、５０～３，０００ｍＪ／ｃｍ２であることが好ましく、１００～６００ｍＪ／ｃｍ２であることがより好ましい。粘着シートに照射するＵＶ照射量が５０ｍＪ／ｃｍ２以上であると、ＵＶ照射することにより十分に速い硬化速度で粘着剤層を硬化させることができるため、ＵＶ照射後の粘着剤層の粘着力を十分に小さくすることができる。粘着シートに照射するＵＶ照射量を３，０００ｍＪ／ｃｍ２超にしても、それに見合う効果が得られないため、粘着シートに照射するＵＶ照射量を３，０００ｍＪ／ｃｍ２以下とすることで、被着体に対するＵＶ照射の影響を軽減しながら、経済的に粘着シートを剥離することができる。 The amount of UV irradiation applied to the adhesive sheet is preferably 50 to 3,000 mJ/cm 2 , more preferably 100 to 600 mJ/cm 2 . When the amount of UV irradiation applied to the adhesive sheet is 50 mJ/cm2 or more, the adhesive layer can be cured at a sufficiently fast curing speed by UV irradiation, so the adhesive strength of the adhesive layer after UV irradiation is can be made sufficiently small. Even if the UV irradiation amount applied to the adhesive sheet exceeds 3,000 mJ/cm 2 , commensurate effects cannot be obtained, so by setting the UV irradiation amount applied to the adhesive sheet to 3,000 mJ/cm 2 or less, The pressure-sensitive adhesive sheet can be peeled off economically while reducing the influence of UV irradiation on the adherend.
　以下、実施例及び比較例により本発明をさらに具体的に説明するが、本発明は以下の実施例に限定されるものではない。 Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.
　（メタ）アクリル樹脂（Ａ）及び（ｃＡ）の合成に用いた原料を以下に示す。
ヒドロキシ基含有（メタ）アクリレート（ｍ－１）：
　２－ヒドロキシエチルアクリレート、株式会社日本触媒、
　２－ヒドロキシエチルメタクリレート、株式会社日本触媒、
　４－ヒドロキシブチルアクリレート、大阪有機化学工業株式会社
アルキル（メタ）アクリレート（ｍ－２）：
　２－エチルヘキシルアクリレート、大阪有機化学工業株式会社、
　ｎ－ブチルアクリレート、大阪有機化学工業株式会社、
　ドデシルアクリレート、大阪有機化学工業株式会社、
　２－メトキシエチルアクリレート、大阪有機化学工業株式会社、
　エチルアクリレート、株式会社日本触媒、
　メチルメタクリレート、株式会社日本触媒
カルボキシ基含有単量体（ｍ－３）：
　アクリル酸、株式会社日本触媒、
　メタクリル酸、株式会社日本触媒
ラジカル重合開始剤：
　２，２’－アゾビス（イソブチロニトリル）、富士フイルム和光純薬株式会社
ＲＡＦＴ剤：
　２－「（ドデシルスルファニルチオカルボニル）スルファニル」プロパン酸、富士フイルム和光純薬株式会社、
　ビス｛４－[エチル－(２－ヒドロキシエチル)カルバモイル]ベンジル｝トリチオカーボネート、富士フイルム和光純薬株式会社、
　Ｓ,Ｓ－ジベンジルトリチオカーボネート、富士フイルム和光純薬株式会社、
　２－フェニル－２－プロピルジチオ安息香酸、大内新興化学工業株式会社
添加剤：
　２－メチル－２－ｎ－ブチルテラニル－プロピオン酸エチル、大塚化学株式会社
イソシアナト基含有エチレン性不飽和化合物（ａ）：
　カレンズ（商標）ＭＯＩ、２－イソシアナトエチルメタクリレート、昭和電工株式会社、
　ＡＯＩ－ＶＭ（商標）、２－イソシアナトエチルアクリレート、昭和電工株式会社 The raw materials used for the synthesis of (meth)acrylic resins (A) and (cA) are shown below.
Hydroxy group-containing (meth)acrylate (m-1):
2-Hydroxyethyl acrylate, Nippon Shokubai Co., Ltd.
2-Hydroxyethyl methacrylate, Nippon Shokubai Co., Ltd.
4-Hydroxybutyl acrylate, Osaka Organic Chemical Industry Co., Ltd. alkyl (meth)acrylate (m-2):
2-Ethylhexyl acrylate, Osaka Organic Chemical Industry Co., Ltd.
n-butyl acrylate, Osaka Organic Chemical Industry Co., Ltd.
Dodecyl acrylate, Osaka Organic Chemical Industry Co., Ltd.
2-methoxyethyl acrylate, Osaka Organic Chemical Industry Co., Ltd.
Ethyl acrylate, Nippon Shokubai Co., Ltd.
Methyl methacrylate, Nippon Shokubai Co., Ltd. carboxy group-containing monomer (m-3):
Acrylic acid, Nippon Shokubai Co., Ltd.
Methacrylic acid, Nippon Shokubai radical polymerization initiator:
2,2'-azobis(isobutyronitrile), Fujifilm Wako Pure Chemical Industries, Ltd. RAFT agent:
2- “(dodecylsulfanylthiocarbonyl)sulfanyl” propanoic acid, Fujifilm Wako Pure Chemical Industries, Ltd.
Bis{4-[ethyl-(2-hydroxyethyl)carbamoyl]benzyl}trithiocarbonate, Fujifilm Wako Pure Chemical Industries, Ltd.
S,S-dibenzyltrithiocarbonate, Fujifilm Wako Pure Chemical Industries, Ltd.
2-phenyl-2-propyldithiobenzoic acid, Ouchi Shinko Chemical Co., Ltd. additive:
Ethyl 2-methyl-2-n-butylterranyl-propionate, Otsuka Chemical Co., Ltd. Isocyanato group-containing ethylenically unsaturated compound (a):
Karenz (trademark) MOI, 2-isocyanatoethyl methacrylate, Showa Denko K.K.
AOI-VM (trademark), 2-isocyanatoethyl acrylate, Showa Denko K.K.
　（メタ）アクリル樹脂（Ａ）及び（ｃＡ）の合成例を以下に示す。（メタ）アクリル樹脂（Ａ）及び（ｃＡ）の重量平均分子量、分子量分布、酸価、及びガラス転移温度は、上述の方法にて測定、算出した。（メタ）アクリル樹脂（Ａ）及び（ｃＡ）のエチレン性不飽和基当量は、上述のとおり仕込み量から算出した。水酸基価は、ＪＩＳ　Ｋ　００７０：１９９２に従って、樹脂１ｇをアセチル化させたときに水酸基と結合した酢酸を、中和するのに要する水酸化カリウムの質量（ｍｇ）である。（メタ）アクリル樹脂（Ａ）及び（ｃＡ）の重量平均分子量、分子量分布、エチレン性不飽和基当量、水酸基価、酸価、及びガラス転移温度を表１に示す。 Synthesis examples of (meth)acrylic resins (A) and (cA) are shown below. The weight average molecular weight, molecular weight distribution, acid value, and glass transition temperature of the (meth)acrylic resins (A) and (cA) were measured and calculated using the methods described above. The ethylenically unsaturated group equivalents of the (meth)acrylic resins (A) and (cA) were calculated from the charged amounts as described above. The hydroxyl value is the mass (mg) of potassium hydroxide required to neutralize acetic acid bonded to hydroxyl groups when 1 g of resin is acetylated, according to JIS K 0070:1992. Table 1 shows the weight average molecular weight, molecular weight distribution, ethylenically unsaturated group equivalent, hydroxyl value, acid value, and glass transition temperature of the (meth)acrylic resins (A) and (cA).
［合成例１（実施例１－１）］
　攪拌機、温度調節器、還流冷却器、滴下ロート、及び温度計を付した反応装置に、２－エチルヘキシルアクリレート１３２質量部（７１．６モル）、２－ヒドロキシエチルアクリレート３３質量部（２８．４モル）、２－［（ドデシルスルファニルチオカルボニル）スルファニル］プロパン酸０．２３質量部、２，２’－アゾビス（イソブチロニトリル）０．０５質量部、及び溶媒として酢酸エチル４７１質量部を仕込んだ。加熱還流を開始した後、１０時間反応させた。次に反応物の温度を６０℃まで下げ、滴下ロートを通じて２－イソシアナトエチルメタクリレート２４．７質量部（１５．９モル）とウレタン化触媒であるジブチル錫ジラウレート０．１９質量部の混合液を滴下した。滴下終了後、反応系を７０℃で４時間保持し、イソシアナト基を消失させた。このことにより、重量平均分子量３００，０００、ガラス転移温度－５０℃、エチレン性不飽和基当量１，１８９ｇ／ｍоｌの（メタ）アクリル樹脂（Ａ１）を含む固形分３５質量％の溶液を得た。 [Synthesis Example 1 (Example 1-1)]
132 parts by mass (71.6 moles) of 2-ethylhexyl acrylate and 33 parts by mass (28.4 moles) of 2-hydroxyethyl acrylate were placed in a reaction apparatus equipped with a stirrer, a temperature regulator, a reflux condenser, a dropping funnel, and a thermometer. ), 0.23 parts by mass of 2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propanoic acid, 0.05 parts by mass of 2,2'-azobis(isobutyronitrile), and 471 parts by mass of ethyl acetate as a solvent were charged. . After starting heating under reflux, the reaction was continued for 10 hours. Next, the temperature of the reactant was lowered to 60°C, and a mixed solution of 24.7 parts by mass (15.9 mol) of 2-isocyanatoethyl methacrylate and 0.19 parts by mass of dibutyltin dilaurate, which is a urethanization catalyst, was added through the dropping funnel. dripped. After the dropwise addition was completed, the reaction system was maintained at 70° C. for 4 hours to eliminate the isocyanate groups. As a result, a solution with a solid content of 35% by mass containing a (meth)acrylic resin (A1) having a weight average molecular weight of 300,000, a glass transition temperature of -50°C, and an ethylenically unsaturated group equivalent of 1,189 g/mol was obtained. .
［合成例２～４（実施例１－２～１－４）］
　表１に示す組成を用いたこと以外は、合成例１と同様にして、（メタ）アクリル樹脂（Ａ２）～（Ａ４）を得た。 [Synthesis Examples 2 to 4 (Examples 1-2 to 1-4)]
(Meth)acrylic resins (A2) to (A4) were obtained in the same manner as Synthesis Example 1 except that the compositions shown in Table 1 were used.
［比較合成例１（比較例１－１）］
　攪拌機、温度調節器、還流冷却器、滴下ロート、及び温度計を付した反応装置に、２－エチルヘキシルアクリレート１３２質量部（７１．６モル）、２－ヒドロキシエチルアクリレート３３質量部（２８．４モル）、２，２’－アゾビス（イソブチロニトリル）０．０８質量部、及び溶媒として酢酸エチル４７１質量部を仕込んだ。加熱還流を開始した後、１０時間反応させた。次に反応物の温度を６０℃まで下げ、滴下ロートを通じて２－イソシアナトエチルメタクリレート１６．５質量部（１０．６モル）とウレタン化触媒であるジブチル錫ジラウレート０．１８質量部の混合液を滴下した。滴下終了後、反応系を７０℃で４時間保持し、イソシアナト基を消失させた。このことにより、重量平均分子量６００，０００、ガラス転移温度－４５℃、エチレン性不飽和基当量１，７０７ｇ／ｍоｌの（メタ）アクリル樹脂（ｃＡ１）を含む固形分３５質量％の溶液を得た。 [Comparative synthesis example 1 (comparative example 1-1)]
132 parts by mass (71.6 moles) of 2-ethylhexyl acrylate and 33 parts by mass (28.4 moles) of 2-hydroxyethyl acrylate were placed in a reaction apparatus equipped with a stirrer, a temperature regulator, a reflux condenser, a dropping funnel, and a thermometer. ), 0.08 parts by mass of 2,2'-azobis(isobutyronitrile), and 471 parts by mass of ethyl acetate as a solvent. After starting heating under reflux, the reaction was continued for 10 hours. Next, the temperature of the reactant was lowered to 60°C, and a mixed solution of 16.5 parts by mass (10.6 mol) of 2-isocyanatoethyl methacrylate and 0.18 parts by mass of dibutyltin dilaurate, which is a urethanization catalyst, was added through the dropping funnel. dripped. After the dropwise addition was completed, the reaction system was maintained at 70° C. for 4 hours to eliminate the isocyanate groups. As a result, a solution with a solid content of 35% by mass containing a (meth)acrylic resin (cA1) having a weight average molecular weight of 600,000, a glass transition temperature of -45°C, and an ethylenically unsaturated group equivalent of 1,707 g/mol was obtained. .
［比較合成例２（比較例１－２）］
　２－［（ドデシルスルファニルチオカルボニル）スルファニル］プロパン酸の代わりに２－メチル－２－ｎ－ブチルテラニル－プロピオン酸エチルを用い、表１に示す組成を用いたこと以外は、合成例１と同様にして、（メタ）アクリル樹脂（ｃＡ２）を得た。 [Comparative synthesis example 2 (comparative example 1-2)]
Synthesis Example 1 was carried out in the same manner as in Synthesis Example 1, except that ethyl 2-methyl-2-n-butylterranyl-propionate was used instead of 2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propanoic acid and the composition shown in Table 1 was used. A (meth)acrylic resin (cA2) was obtained.
［比較合成例３（比較例１－３）］
　表１に示す組成を用いたこと以外は、合成例１と同様にして、（メタ）アクリル樹脂（ｃＡ３）を得た。 [Comparative synthesis example 3 (comparative example 1-3)]
A (meth)acrylic resin (cA3) was obtained in the same manner as Synthesis Example 1 except that the composition shown in Table 1 was used.
　粘着剤組成物の調製に用いた原料を以下に示す。
光重合開始剤（Ｂ）：
　ＴＰＯ：２，４，６－トリメチルベンゾイルジフェニルホスフィンオキサイド（ＢＡＳＦ社、商品名：Ｌ－ＴＰＯ）
架橋剤（Ｃ）
　Ｌ－４５Ｅ：トリメチロールプロパンのトリレンジイソシアネート付加物（東ソー株式会社、商品名：コロネートＬ－４５Ｅ）、
　ＴＥＴＲＡＤ－Ｘ：Ｎ，Ｎ’－［１，３－フェニレンビス（メチレン）］ビス［ビス（オキシラン－２－イルメチル）アミン］（三菱ガス化学株式会社製、商品名：ＴＥＴＲＡＤ－Ｘ） The raw materials used for preparing the adhesive composition are shown below.
Photopolymerization initiator (B):
TPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide (BASF, trade name: L-TPO)
Crosslinking agent (C)
L-45E: tolylene diisocyanate adduct of trimethylolpropane (Tosoh Corporation, product name: Coronate L-45E),
TETRAD-X: N,N'-[1,3-phenylenebis(methylene)]bis[bis(oxiran-2-ylmethyl)amine] (manufactured by Mitsubishi Gas Chemical Co., Ltd., product name: TETRAD-X)
［粘着剤組成物の調製］
　合成例１～４及び比較合成例１～３で得た（メタ）アクリル樹脂（Ａ１）～（Ａ４）及び（ｃＡ１）～（ｃＡ３）を含む溶液に、希釈溶媒である酢酸エチルを加え、それぞれ（メタ）アクリル樹脂（Ａ１）～（Ａ４）及び（ｃＡ１）～（ｃＡ３）の含有量が３０質量％となるように調整した。この溶液を用いて、以下に示す方法により粘着剤組成物を得た。 [Preparation of adhesive composition]
Ethyl acetate as a diluting solvent was added to the solutions containing the (meth)acrylic resins (A1) to (A4) and (cA1) to (cA3) obtained in Synthesis Examples 1 to 4 and Comparative Synthesis Examples 1 to 3, respectively. The content of (meth)acrylic resins (A1) to (A4) and (cA1) to (cA3) was adjusted to 30% by mass. Using this solution, an adhesive composition was obtained by the method shown below.
　活性線の遮断された室内でプラスチック製容器に、表２に示す（メタ）アクリル樹脂（Ａ）又は（ｃＡ）と光重合開始剤（Ｂ）と架橋剤（Ｃ）とを、それぞれ表２に示す含有量（質量部）で加えて攪拌し、粘着剤組成物（Ｂ１）～（Ｂ４）及び（ｃＢ１）～（ｃＢ３）を得た。表２中の（メタ）アクリル樹脂（Ａ１）～（Ａ４）及び（メタ）アクリル（ｃＡ１）～（ｃＡ３）の数値は、用いた溶液の固形分、すなわち（メタ）アクリル樹脂（Ａ１）～（Ａ４）及び（ｃＡ１）～（ｃＡ３）の使用量（質量部）である。光重合開始剤（Ｂ）の数値は、（メタ）アクリル樹脂（Ａ）又は（ｃＡ）１００質量部に対する光重合開始剤（Ｂ）の使用量（質量部）である。架橋剤（Ｃ）の数値は、（メタ）アクリル樹脂（Ａ）又は（ｃＡ）１００質量部に対する架橋剤（Ｃ）の使用量（質量部）である。 The (meth)acrylic resin (A) or (cA) shown in Table 2, the photopolymerization initiator (B), and the crosslinking agent (C) shown in Table 2 were placed in a plastic container in a room blocked from active rays. The indicated content (parts by mass) was added and stirred to obtain adhesive compositions (B1) to (B4) and (cB1) to (cB3). The numerical values of (meth)acrylic resins (A1) to (A4) and (meth)acrylic resins (cA1) to (cA3) in Table 2 are based on the solid content of the solutions used, that is, (meth)acrylic resins (A1) to ( A4) and the amounts used (parts by mass) of (cA1) to (cA3). The numerical value of the photopolymerization initiator (B) is the amount (parts by mass) of the photopolymerization initiator (B) used per 100 parts by mass of the (meth)acrylic resin (A) or (cA). The numerical value of the crosslinking agent (C) is the amount (parts by mass) of the crosslinking agent (C) used per 100 parts by mass of the (meth)acrylic resin (A) or (cA).
［実施例２－１］粘着シートの作製
　セパレーターとして、シリコーン系の軽剥離ＰＥＴフィルム（東洋紡株式会社、品名：Ｅ７００６、厚さ２５μｍ）を用意し、離型処理が施された面に対して、アプリケーターを用いて粘着剤組成物（Ｂ１）を、硬化後の厚さが２０μｍとなるように塗布し、１００℃で２分間加熱乾燥させて、粘着剤層を形成した。次に、シート状の基材として、厚さ９０μｍのＰＯフィルムを用意した。粘着剤層の露出面にＰＯフィルムのコロナ処理面が接着するように、ＰＯフィルムを粘着剤層にゴムローラーを使用して貼り付けた。４０℃で３日間、オーブンで養生し、粘着剤層を架橋硬化させて実施例２－１の粘着シートを得た。 [Example 2-1] Preparation of adhesive sheet A silicone-based light release PET film (Toyobo Co., Ltd., product name: E7006, thickness 25 μm) was prepared as a separator, and the release-treated surface was The adhesive composition (B1) was applied using an applicator so that the thickness after curing was 20 μm, and the adhesive composition was dried by heating at 100° C. for 2 minutes to form an adhesive layer. Next, a 90 μm thick PO film was prepared as a sheet-like base material. The PO film was attached to the adhesive layer using a rubber roller so that the corona-treated surface of the PO film adhered to the exposed surface of the adhesive layer. The pressure-sensitive adhesive sheet of Example 2-1 was obtained by curing in an oven at 40° C. for 3 days to crosslink and cure the pressure-sensitive adhesive layer.
［実施例２－２～２－４及び比較例２－１～２－３］粘着シートの作製
　粘着剤組成物（Ｂ１）に代えて、表２に記載の粘着剤組成物を用いたこと以外は、実施例２－１と同様にして、実施例２－２～２－４及び比較例２－１～２－３の粘着シートを得た。 [Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-3] Production of adhesive sheets Except for using the adhesive composition shown in Table 2 instead of the adhesive composition (B1) Adhesive sheets of Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-3 were obtained in the same manner as in Example 2-1.
[ダイシング・ダイボンディング一体型フィルムの作製]
　接着剤層の両面がカバーフィルムで保護されているダイボンディングフィルム（ＦＨ－Ｄ２５Ｔ－５０、昭和電工マテリアルズ株式会社）の片面のカバーフィルムを剥離して接着剤層を露出させた。この接着剤層と、軽剥離ＰＥＴフィルムを剥離して粘着剤層を露出させた、実施例２－１～２－４及び比較例２－１～２－３の粘着シートの粘着剤層とをゴムローラーで貼り合わせた。室温で１日放置し、ダイシング・ダイボンディング一体型フィルムを得た。 [Production of integrated dicing and die bonding film]
The cover film on one side of a die bonding film (FH-D25T-50, Showa Denko Materials Co., Ltd.), in which both sides of the adhesive layer were protected by cover films, was peeled off to expose the adhesive layer. This adhesive layer and the adhesive layer of the adhesive sheets of Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-3, in which the easy-release PET film was peeled off to expose the adhesive layer, were Pasted together with a rubber roller. After being left at room temperature for one day, a dicing/die bonding integrated film was obtained.
［評価］
（１）ＵＶ照射前粘着力（３０°ピール強度）の測定
　以下のとおり、実施例及び比較例に係る粘着シートのダイボンディングフィルムに対する粘着力を３０°ピール強度を測定することによって評価した。ダイシング・ダイボンディング一体型フィルムから幅２５ｍｍ及び長さ１００ｍｍの試料を切り出した。ダイシング・ダイボンディング一体型フィルムの粘着シートが貼付されていない方のカバーフィルムを剥がし、接着剤層をポリカーボネート板に両面テープを用いて貼り付け、粘着力測定用サンプルを得た。引張試験機（ＶＰＡ-Ｈ２００、協和界面科学株式会社）を用いてダイボンディングフィルムに対する粘着シートのピール強度を測定した。測定条件は、剥離角度３０°、引張速度６００ｍｍ／分とした。なお、試料の保存及びピール強度の測定は、温度２３℃、相対湿度４０％の環境下で行った。表２に結果を示す。 [evaluation]
(1) Measurement of adhesive strength (30° peel strength) before UV irradiation As described below, the adhesive strength of the adhesive sheets of Examples and Comparative Examples to the die bonding film was evaluated by measuring the 30° peel strength. A sample with a width of 25 mm and a length of 100 mm was cut out from the dicing/die bonding integrated film. The cover film of the dicing/die bonding integrated film to which the adhesive sheet was not attached was peeled off, and the adhesive layer was attached to a polycarbonate plate using double-sided tape to obtain a sample for adhesive strength measurement. The peel strength of the adhesive sheet against the die bonding film was measured using a tensile tester (VPA-H200, Kyowa Interface Science Co., Ltd.). The measurement conditions were a peel angle of 30° and a tensile speed of 600 mm/min. Incidentally, the storage of the samples and the measurement of peel strength were performed under an environment of a temperature of 23° C. and a relative humidity of 40%. Table 2 shows the results.
（２）ＵＶ照射後粘着力（３０°ピール強度）の測定
　ダイシング・ダイボンディング一体型フィルムに対して粘着シートの基材側の面から照射量３００ｍＪ／ｃｍ２の条件で紫外線（ＵＶ）を照射し、ＵＶ照射後粘着力の測定用サンプルを得た。ＵＶ照射には、コンベヤー型紫外線照射装置（アイグラフィックス株式会社、２ＫＷランプ、８０Ｗ／ｃｍ）を用いた。その後、ＵＶ照射前粘着力（３０°ピール強度）の測定と同じ方法でダイボンディングフィルムに対する粘着シートのピール強度を測定した。表２に結果を示す。 (2) Measurement of adhesive strength (30° peel strength) after UV irradiation The dicing/die bonding integrated film is irradiated with ultraviolet rays (UV) from the base material side of the adhesive sheet at an irradiation dose of 300 mJ/cm 2 A sample for measuring adhesive strength was obtained after UV irradiation. For UV irradiation, a conveyor type ultraviolet irradiation device (I-Graphics Co., Ltd., 2KW lamp, 80W/cm) was used. Thereafter, the peel strength of the adhesive sheet with respect to the die bonding film was measured in the same manner as the measurement of the adhesive strength (30° peel strength) before UV irradiation. Table 2 shows the results.
（３）プロセス性評価
（ｉ）プロセス性評価用試料の作製
　シリコンウェハ（直径：１２インチ、厚さ：７７５μｍ）の表面に保護テープ（ＢＧテープ）を貼り付けた。その後、シリコンウェハのステルスダイシングを行った。すなわち、ＢＧテープが貼り付けられた側と反対側のシリコンウェハの面（裏面）に対して以下条件でレーザ光を照射することによって、シリコンウェハ内部に改質層を形成した。
＜ステルスダイシング条件＞
・ステルスダイシング装置：ＤＦＬ７３６１（株式会社ディスコ）
・レーザ発振器型式：Ｑスイッチ半導体励起固体レーザ
・波長：１３４２ｎｍ
・周波数：９０ｋＨｚ
・出力：１．７Ｗ
・パス数：２
・チップサイズ：１０ｍｍ×１０ｍｍ
・ダイシング速度：７００ｍｍ／秒 (3) Process performance evaluation (i) Preparation of sample for process performance evaluation A protective tape (BG tape) was attached to the surface of a silicon wafer (diameter: 12 inches, thickness: 775 μm). After that, stealth dicing of the silicon wafer was performed. That is, a modified layer was formed inside the silicon wafer by irradiating the surface (back surface) of the silicon wafer opposite to the side to which the BG tape was attached with laser light under the following conditions.
<Stealth dicing conditions>
・Stealth dicing device: DFL7361 (Disco Co., Ltd.)
・Laser oscillator type: Q-switch semiconductor pumped solid-state laser ・Wavelength: 1342nm
・Frequency: 90kHz
・Output: 1.7W
・Number of passes: 2
・Chip size: 10mm x 10mm
・Dicing speed: 700mm/sec
　ステルスダイシング後のシリコンウェハを厚さ３０μｍになるまで研磨した。研磨にはグラインダポリッシャ装置（ＤＧＰ８７６１、株式会社ディスコ）を使用した。研磨後のシリコンウェハにダイシング・ダイボンディング一体型フィルムの接着剤層を、ダイシングテープの基材側の面をダイシングリングに向けて以下条件で貼り付けた。その後、シリコンウェハの表面からＢＧテープを剥離した。
＜貼付条件＞
・貼付装置：ＤＦＭ２８００（株式会社ディスコ）
・貼付温度：７０℃
・貼付速度：１０ｍｍ／ｓ
・貼付テンションレベル：レベル６ The silicon wafer after stealth dicing was polished to a thickness of 30 μm. A grinder polisher device (DGP8761, DISCO Co., Ltd.) was used for polishing. An adhesive layer of a dicing/die bonding integrated film was attached to the polished silicon wafer under the following conditions with the base side surface of the dicing tape facing the dicing ring. Thereafter, the BG tape was peeled off from the surface of the silicon wafer.
<Pasting conditions>
・Packing device: DFM2800 (Disco Co., Ltd.)
・Application temperature: 70℃
・Application speed: 10mm/s
・Application tension level: Level 6
　次いで、ダイセパレータ（ＤＤＳ２３００、株式会社ディスコ）を使用して以下条件で冷却エキスパンドした。その後、ダイシング・ダイボンディング一体型フィルムの基材層（ＰＯフィルム）を以下の条件でヒートシュリンクさせた。これらの工程を経て、シリコンウェハ及び接着剤層を複数の接着剤片付きチップ（サイズ１０ｍｍ×１０ｍｍ）に個片化した。
＜冷却エキスパンド条件＞
・冷却温度：－１５℃
・冷却時間：１２０秒
・突上げ量：１２ｍｍ
・突上げ速度：２００ｍｍ／秒
・突上げ後の保持時間：３秒
＜ヒートシュリンク条件＞
・ヒータ温度：２２０℃
・ヒータ回転速度：５°／秒
・突上げ量：８ｍｍ
・テープ冷却待ち時間：１０秒 Then, using a die separator (DDS2300, DISCO Co., Ltd.), it was cooled and expanded under the following conditions. Thereafter, the base material layer (PO film) of the dicing/die bonding integrated film was heat-shrinked under the following conditions. Through these steps, the silicon wafer and the adhesive layer were diced into a plurality of chips with adhesive chips (size: 10 mm x 10 mm).
<Cooling expansion conditions>
・Cooling temperature: -15℃
・Cooling time: 120 seconds ・Push-up amount: 12mm
・Push-up speed: 200mm/sec ・Holding time after push-up: 3 seconds <Heat shrink conditions>
・Heater temperature: 220℃
・Heater rotation speed: 5°/sec ・Listing amount: 8mm
・Tape cooling waiting time: 10 seconds
　シリコンウェハ及び接着剤層を個片化した後、粘着剤層に対して粘着シートの基材側の面から以下の条件で紫外線照射を行った。これにより、粘着剤層を硬化させて接着剤層に対する粘着力を低下させた。
＜紫外線照射条件＞
・紫外線の照度：１００ｍＷ／ｃｍ２
・紫外線の照射量：１５０ｍＪ／ｃｍ２ After cutting the silicon wafer and the adhesive layer into pieces, the adhesive layer was irradiated with ultraviolet rays from the surface of the adhesive sheet on the base material side under the following conditions. This cured the adhesive layer and reduced the adhesive force to the adhesive layer.
<Ultraviolet irradiation conditions>
・Illuminance of ultraviolet rays: 100mW/ cm2
・Ultraviolet irradiation amount: 150mJ/ cm2
（ｉｉ）プロセス性の評価
（ＤＡＦ飛び）
　冷却エキスパンド及びヒートシュリンク後に、ＤＡＦ飛びについて以下の基準で評価した。表２に結果を示す。
　Ａ：ＤＡＦ飛びが全く発生しなかった。
　Ｂ：ＤＡＦ飛びには至らなかったが、接着剤層と粘着剤層との界面で剥離又は浮きが認められた。
　Ｃ：ＤＡＦ飛びが少なくとも一箇所で発生した。 (ii) Evaluation of processability (DAF jump)
After cooling expansion and heat shrinking, DAF jump was evaluated according to the following criteria. Table 2 shows the results.
A: DAF jump did not occur at all.
B: DAF did not fly, but peeling or lifting was observed at the interface between the adhesive layer and the pressure-sensitive adhesive layer.
C: DAF skipping occurred in at least one location.
（チップエッジ剥離）
　冷却エキスパンド及びヒートシュリンク後に、接着剤片付きチップのエッジ部における接着剤層と粘着剤層の剥離について以下の基準で評価した。表２に結果を示す。
　Ａ：エッジ部において剥離が全く見られなかった。
　Ｂ：エッジ部から１ｍｍ以上２ｍｍ未満の長さで剥離が見られた。
　Ｃ：エッジ部から２ｍｍ以上３ｍｍ未満の長さで剥離が見られた。
　Ｄ：エッジ部から３ｍｍ以上の長さで剥離が見られた。 (chip edge peeling)
After cooling expansion and heat shrinking, peeling between the adhesive layer and the pressure-sensitive adhesive layer at the edge portion of the chip with the adhesive piece was evaluated according to the following criteria. Table 2 shows the results.
A: No peeling was observed at the edge portion.
B: Peeling was observed at a length of 1 mm or more and less than 2 mm from the edge portion.
C: Peeling was observed at a length of 2 mm or more and less than 3 mm from the edge.
D: Peeling was observed at a length of 3 mm or more from the edge.
（接着剤層の分断性）
　冷却エキスパンド及びヒートシュリンク後のシリコンウェハの全面を顕微鏡で観察し、接着剤層の分断性を以下の基準で評価した。表２に結果を示す。
　Ａ：接着剤層が完全に分断されていた。
　Ｄ：接着剤層の少なくとも一箇所に分断されていない部分があった。 (Separability of adhesive layer)
The entire surface of the silicon wafer after cooling expansion and heat shrinking was observed under a microscope, and the breakability of the adhesive layer was evaluated based on the following criteria. Table 2 shows the results.
A: The adhesive layer was completely separated.
D: There was an undivided portion in at least one part of the adhesive layer.
（カーフ幅）
　個片化後の接着剤片付きチップの間隔（カーフ幅）を顕微鏡を用いて測長した。シリコンウェハ外周部（上下左右）の二箇所ずつと、中央部の一箇所についてＭＤ／ＴＤ方向のカーフ幅をそれぞれ測長（計１８点）し、その平均値を求めた。以下の基準で評価した。表２に結果を示す。
　Ｓ：カーフ幅の平均値が１００μｍ以上１５０μｍ未満であった。
　Ａ：カーフ幅の平均値が７０μｍ以上１００μｍ未満であった。
　Ｂ：カーフ幅の平均値が５０μｍ以上７０μｍ未満であった。 (kerf width)
The interval (kerf width) between the chips with adhesive chips after singulation was measured using a microscope. The kerf width in the MD/TD direction was measured at two locations each on the outer periphery (top, bottom, left and right) of the silicon wafer and at one location in the center (total of 18 points), and the average value was determined. Evaluation was made based on the following criteria. Table 2 shows the results.
S: The average value of the kerf width was 100 μm or more and less than 150 μm.
A: The average value of the kerf width was 70 μm or more and less than 100 μm.
B: The average value of the kerf width was 50 μm or more and less than 70 μm.
（ピックアップ性）
　上記の評価を実施した後、以下の条件で１００個の接着剤片付きチップをピックアップし、以下の基準で評価した。表２に結果を示す。
＜ピックアップ条件＞
・ダイボンダ装置：ＤＢ－８３０Ｐ（ファスフォードテクノロジ株式会社）
・突上げピン：ＥＪＥＣＴＯＲ　ＮＥＥＤＬＥ　ＳＥＮ２－８３－０５（直径：０．７ｍｍ、先端形状：半径３５０μｍの半球、マイクロメカニクス社）
・突き上げ高さ：２５０μｍ
・突き上げ速度：１ｍｍ／秒
・突上げピン数：９本
＜評価基準＞
　Ａ：ピックアップの成功率が１００％であった。
　Ｂ：ピックアップの成功率が８０％以上１００％未満であった。
　Ｃ：ピックアップの成功率が６０％以上８０％未満であった。 (Pickup property)
After carrying out the above evaluation, 100 adhesive-attached chips were picked up under the following conditions and evaluated according to the following criteria. Table 2 shows the results.
<Pickup conditions>
・Die bonder device: DB-830P (Fasford Technology Co., Ltd.)
- Push-up pin: EJECTOR NEEDLE SEN2-83-05 (diameter: 0.7 mm, tip shape: hemisphere with a radius of 350 μm, Micro Mechanics)
・Push-up height: 250μm
・Push-up speed: 1mm/sec ・Number of push-up pins: 9 <Evaluation criteria>
A: The success rate of pickup was 100%.
B: The success rate of pickup was 80% or more and less than 100%.
C: The success rate of pickup was 60% or more and less than 80%.
　実施例２－１～２－３に係る粘着シートを用いて作製したダイシング・ダイボンディング一体型フィルムはプロセス性評価の結果がいずれも良好であった。特に、実施例２－１、２－２、及び２－４はカーフ幅の評価が「Ｓ」であった。カーフ幅は、優れたピックアップ性を達成する観点から、ステルスダイシングのプロセスにおいて重要視される項目の一つである。一方で、いずれの比較例もカーフ幅の評価は「Ｂ」であった。加えて、いずれの比較例も冷却エキスパンド及びヒートシュリンクの後にチップエッジ剥離が発生し、ピックアップ不良も発生した。有機テルルラジカル重合により製造された共重合体から得られた（メタ）アクリル樹脂を用いた比較例２－２は、低分子量成分が少なく破断応力の伝播が不十分であったため、接着剤層分断性がＤであった。 The dicing/die bonding integrated films produced using the pressure-sensitive adhesive sheets according to Examples 2-1 to 2-3 all had good results in processability evaluation. In particular, Examples 2-1, 2-2, and 2-4 were evaluated as "S" for kerf width. Kerf width is one of the important items in the stealth dicing process from the viewpoint of achieving excellent pick-up properties. On the other hand, the evaluation of the kerf width in all comparative examples was "B". In addition, in all comparative examples, chip edge peeling occurred after cooling expansion and heat shrinking, and pickup failure also occurred. Comparative Example 2-2, which used a (meth)acrylic resin obtained from a copolymer produced by organic tellurium radical polymerization, had a small amount of low molecular weight components and insufficient propagation of breaking stress, resulting in adhesive layer separation. The gender was D.
　本開示によれば、粘着剤組成物に好適な（メタ）アクリル樹脂が提供される。（メタ）アクリル樹脂を用いて製造された粘着剤組成物により形成された粘着剤層は、再剥離型粘着シート、特にダイシング・ダイボンド一体型フィルムの粘着剤層として好ましく用いることができる。 According to the present disclosure, a (meth)acrylic resin suitable for an adhesive composition is provided. A pressure-sensitive adhesive layer formed from a pressure-sensitive adhesive composition produced using a (meth)acrylic resin can be preferably used as a pressure-sensitive adhesive layer of a removable pressure-sensitive adhesive sheet, particularly a dicing/die-bonding integrated film.

Claims (10)

  1. 　ヒドロキシ基含有（メタ）アクリレート（ｍ－１）、及びアルキル（メタ）アクリレート（ｍ－２）を含有する原料モノマー群（Ｍ）を可逆的付加開裂連鎖移動（ＲＡＦＴ）重合して、共重合体（Ａ－０）を得る工程（ｉ）と、
    　前記共重合体（Ａ－０）が有する側鎖ヒドロキシ基の一部にイソシアナト基含有エチレン性不飽和化合物（ａ）を付加して、エチレン性不飽和基を有する（メタ）アクリル樹脂（Ａ）を得る工程（ｉｉ）と、
    を含む（メタ）アクリル樹脂の製造方法。     A copolymer is obtained by polymerizing a raw material monomer group (M) containing a hydroxy group-containing (meth)acrylate (m-1) and an alkyl (meth)acrylate (m-2) by reversible addition-fragmentation chain transfer (RAFT). Step (i) of obtaining (A-0);
    An isocyanato group-containing ethylenically unsaturated compound (a) is added to a part of the side chain hydroxyl groups of the copolymer (A-0) to produce a (meth)acrylic resin (A) having an ethylenically unsaturated group. Step (ii) of obtaining
    A method for producing a (meth)acrylic resin containing.
  2. 　前記原料モノマー群（Ｍ）が、カルボキシ基含有単量体（ｍ－３）をさらに含有する請求項１に記載の（メタ）アクリル樹脂の製造方法。 The method for producing a (meth)acrylic resin according to claim 1, wherein the raw material monomer group (M) further contains a carboxy group-containing monomer (m-3).
  3. 　前記エチレン性不飽和基を有する（メタ）アクリル樹脂（Ａ）の分子量分布（Ｍｗ／Ｍｎ）が２．４～１０．０である請求項１又は２に記載の（メタ）アクリル樹脂の製造方法。 The method for producing a (meth)acrylic resin according to claim 1 or 2, wherein the (meth)acrylic resin (A) having an ethylenically unsaturated group has a molecular weight distribution (Mw/Mn) of 2.4 to 10.0. .
  4. 　請求項１又は２に記載の製造方法により得られる、エチレン性不飽和基を有する（メタ）アクリル樹脂（Ａ）と、光重合開始剤（Ｂ）と、架橋剤（Ｃ）とを混合する工程（ｉｉｉ）を含む粘着剤組成物の製造方法。 A step of mixing a (meth)acrylic resin (A) having an ethylenically unsaturated group obtained by the production method according to claim 1 or 2, a photopolymerization initiator (B), and a crosslinking agent (C). A method for producing an adhesive composition comprising (iii).
  5. 　前記架橋剤（Ｃ）が、ポリイソシアネート、及びポリエポキシ化合物からなる群から選択される少なくとも一種である請求項４に記載の粘着剤組成物の製造方法。 The method for producing an adhesive composition according to claim 4, wherein the crosslinking agent (C) is at least one selected from the group consisting of polyisocyanates and polyepoxy compounds.
  6. 　請求項４に記載の製造方法により得られる粘着剤組成物に架橋構造を形成させる工程を含む粘着剤層の製造方法。 A method for producing an adhesive layer, comprising a step of forming a crosslinked structure in the adhesive composition obtained by the production method according to claim 4.
  7. 　請求項４に記載の製造方法により得られる粘着剤組成物をシート状の基材に塗布して粘着剤層を作製することを含む粘着シートの製造方法。 A method for producing a pressure-sensitive adhesive sheet, comprising applying the pressure-sensitive adhesive composition obtained by the production method according to claim 4 to a sheet-like base material to produce a pressure-sensitive adhesive layer.
  8. 　請求項７に記載の製造方法により得られる粘着剤層に架橋構造を形成させる工程を含む粘着シートの製造方法。 A method for producing a pressure-sensitive adhesive sheet, comprising a step of forming a crosslinked structure in the pressure-sensitive adhesive layer obtained by the production method according to claim 7.
  9. 　請求項８に記載の製造方法により得られる、架橋構造を形成された粘着剤層に接着剤層を積層することを含むダイシング・ダイボンディング一体型フィルムの製造方法。 A method for producing a dicing/die bonding integrated film, which is obtained by the production method according to claim 8 and includes laminating an adhesive layer on an adhesive layer formed with a crosslinked structure.
  10. 　請求項４に記載の製造方法により得られる粘着剤組成物を接着剤層に塗布することを含むダイシング・ダイボンディング一体型フィルムの製造方法。 A method for producing a dicing/die bonding integrated film, which comprises applying an adhesive composition obtained by the production method according to claim 4 to an adhesive layer.
PCT/JP2023/026014 2022-08-03 2023-07-14 Method for producing (meth)acrylic resin and method for producing adhesive composition WO2024029315A1 (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005307097A (en) * 2004-04-26 2005-11-04 Kaneka Corp Macromonomer
JP2016145304A (en) * 2015-02-09 2016-08-12 ユニマテック株式会社 Fluorine-containing 2-block copolymer having polymerizable unsaturated group
JP2017066372A (en) * 2015-09-30 2017-04-06 日本合成化学工業株式会社 Acrylic resin, acrylic adhesive composition, adhesive sheet
WO2017061132A1 (en) * 2015-10-05 2017-04-13 リンテック株式会社 Sheet for semiconductor processing
JP2017119758A (en) * 2015-12-28 2017-07-06 綜研化学株式会社 Composition for adhesive, adhesive layer and adhesive sheet
WO2019111758A1 (en) * 2017-12-07 2019-06-13 リンテック株式会社 Sheet for workpiece processing and method for producing processed workpiece

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005307097A (en) * 2004-04-26 2005-11-04 Kaneka Corp Macromonomer
JP2016145304A (en) * 2015-02-09 2016-08-12 ユニマテック株式会社 Fluorine-containing 2-block copolymer having polymerizable unsaturated group
JP2017066372A (en) * 2015-09-30 2017-04-06 日本合成化学工業株式会社 Acrylic resin, acrylic adhesive composition, adhesive sheet
WO2017061132A1 (en) * 2015-10-05 2017-04-13 リンテック株式会社 Sheet for semiconductor processing
JP2017119758A (en) * 2015-12-28 2017-07-06 綜研化学株式会社 Composition for adhesive, adhesive layer and adhesive sheet
WO2019111758A1 (en) * 2017-12-07 2019-06-13 リンテック株式会社 Sheet for workpiece processing and method for producing processed workpiece

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