Classifications

• • 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
  • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
  • C09J11/02—Non-macromolecular additives
  • C09J11/06—Non-macromolecular additives organic
• • 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
  • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
  • C09J11/08—Macromolecular additives
• • 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
  • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
  • C09J133/02—Homopolymers or copolymers of acids; Metal or ammonium salts thereof
• • 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
  • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
  • C09J133/04—Homopolymers or copolymers of esters
  • C09J133/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical
• • 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
  • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
  • C09J133/04—Homopolymers or copolymers of esters
  • C09J133/14—Homopolymers or copolymers of esters of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen
• • 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
  • C09J143/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing boron, silicon, phosphorus, selenium, tellurium, or a metal; Adhesives based on derivatives of such polymers
  • C09J143/04—Homopolymers or copolymers of monomers containing silicon
• • 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
  • C09J7/00—Adhesives in the form of films or foils
  • C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
  • C09J7/38—Pressure-sensitive adhesives [PSA]

Definitions

• the present invention relates to an adhesive composition, a copolymer dispersion, a set, an adhesive tape, and an adhesive method.
• Adhesive tape is a typical use of adhesives.
• a layer containing an adhesive that is, an adhesive layer is formed on a base material, and the adhesive tape is attached to the articles, for example, for repairing various articles or fixing the articles to each other.
• a double-sided adhesive tape having an adhesive layer formed on both sides of a base material is used in a wide range of applications such as transportation equipment such as automobiles, home appliances, and stationery.
• an adhesive layer is formed on the surface of the substrate by applying a coating liquid in which an adhesive is dissolved or dispersed in a liquid medium onto the substrate and drying it.
• Natural rubber-based, synthetic rubber-based, and acrylic-based adhesives are widely used as adhesives, and acrylic-based adhesives are particularly characterized in that they can impart various functionalities.
• the use of water as a liquid medium has been widely studied.
• an acrylic resin emulsion pressure-sensitive adhesive compounding solution obtained by adding a volatile surfactant to an acrylic resin emulsion pressure-sensitive adhesive polymerized using a reactive surfactant is applied to a base film.
• a tape for processing a wafer which is characterized by being made of. It is described that the acrylic resin emulsion pressure-sensitive adhesive is obtained by polymerizing a monomer containing a carboxylic acid-containing vinyl compound.
• tetramethylol-tri- ⁇ -aziridinyl propionate is added to the pressure-sensitive adhesive compounding solution.
• Patent Document 2 describes a removable pressure-sensitive adhesive sheet in which the pressure-sensitive adhesive layer contains adhesive fine particles, a binder, a tack fire, and a cross-linking agent having a carbodiimide group. Further, in Examples and the like, acrylic acid is used as a monomer in the synthesis of adhesive fine particles.
• Patent Document 3 describes, in Example 1, an acrylic pressure-sensitive adhesive aqueous dispersion containing a copolymer copolymerized with a monomer containing acrylic acid and an epoxy cross-linking agent. Further, in Example 3 and the like, an acrylic pressure-sensitive adhesive aqueous dispersion containing a copolymer obtained by copolymerizing acrylic acid and a silane coupling agent and an oxazoline-based cross-linking agent is described.
• Patent Document 4 describes an emulsion obtained by emulsion polymerization of a monomer mixture containing (meth) acrylic acid alkyl ester, a carboxyl group-containing unsaturated monomer, a polyfunctional unsaturated monomer, and other unsaturated monomers, and a cross-linking agent.
• a removable aqueous pressure-sensitive adhesive composition containing the above is described.
• another unsaturated monomer a monomer having an alkoxysilyl group is exemplified.
• the cross-linking agent is at least one selected from an oxazoline-based compound, a carbodiimide-based compound, an epoxy-based compound, and an aziridine-based compound.
• Japanese Unexamined Patent Publication No. 5-171117 Japanese Unexamined Patent Publication No. 2005-126479 Japanese Unexamined Patent Publication No. 2013-189645 Japanese Unexamined Patent Publication No. 2004-256789
• Patent Documents 1 and 2 there is room for improvement in adhesive strength and holding power in a high temperature environment.
• Example 1 of Patent Document 3 has room for improvement in holding power in a high temperature environment when applied to an adhesive tape. Further, when the configuration of Example 2 or the like of Patent Document 3 is applied to an adhesive tape, there is room for improvement in the adhesive force and the holding force in a high temperature environment.
• a pressure-sensitive adhesive composition capable of forming a pressure-sensitive adhesive layer that exhibits strong adhesive strength not only at room temperature but also at high temperature and also has high holding power at high temperature.
• Another object of the present invention is to provide an adhesive tape that exhibits strong adhesive force not only at room temperature but also at high temperature and also has high holding power at high temperature.
• a pressure-sensitive adhesive composition containing a copolymer (A), a cross-linking agent (B), and an aqueous medium.
• the copolymer (A) includes a structural unit derived from the monomer (a1), a structural unit derived from the monomer (a2) having a carboxy group, and a structural unit derived from the monomer (a3) having an alkoxysilyl group.
• the monomer (a1) comprises either or both of a (meth) acrylic acid alkyl ester having only one ethylenically unsaturated bond and a hydrocarbon having only one ethylenically unsaturated bond.
• the content of the structural unit derived from the monomer (a2) in the copolymer (A) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 1.0 part by mass or more and 12 parts by mass or less.
• the content of the structural unit derived from the monomer (a3) in the copolymer (A) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 0.010 parts by mass or more and 3.5 parts by mass or less.
• the cross-linking agent (B) contains one or more selected from the group consisting of a polycarbodiimide compound, a polyepoxy compound, and a polyisocyanate compound.
• the copolymer (A) has a structural unit derived from the monomer (a4) having a hydroxy group, and the monomer (a1) of the structural unit derived from the monomer (a4) in the copolymer (A).
• the copolymer (A) contains a total of 90% by mass or more of a structural unit derived from the monomer (a1), a structural unit derived from the monomer (a2), and a structural unit derived from the monomer (a3).
• ⁇ 5> The pressure-sensitive adhesive composition according to ⁇ 1> to ⁇ 4>, wherein the glass transition point of the copolymer (A) is ⁇ 80 ° C. or higher and 30 ° C. or lower.
• ⁇ 6> The pressure-sensitive adhesive composition according to any one of ⁇ 1> to ⁇ 5>, wherein the monomer (a1) comprises a (meth) acrylic acid alkyl ester.
• ⁇ 7> The above-mentioned one of ⁇ 1> to ⁇ 6>, wherein the total content of the dialkoxysilyl group and the trialkoxysilyl group in the total alkoxysilyl group contained in the copolymer (A) is 80 mol% or more.
• Adhesive composition Adhesive composition.
• ⁇ 8> The pressure-sensitive adhesive composition according to any one of ⁇ 1> to ⁇ 7>, wherein the content of the trialkoxysilyl group in all the alkoxysilyl groups contained in the copolymer (A) is 70 mol% or more.
• the cross-linking agent (B) is a polycarbodiimide compound.
• the carbodiimide equivalent of the cross-linking agent (B) is 150 or more and 1000 or less.
• ⁇ 11> The pressure-sensitive adhesive composition according to any one of ⁇ 1> to ⁇ 8>, wherein the cross-linking agent (B) is a polyepoxy compound.
• the cross-linking agent (B) has an epoxy equivalent of 70 or more and 700 or less.
• ⁇ 13> The pressure-sensitive adhesive composition according to any one of ⁇ 1> to ⁇ 12>, wherein the total content of the copolymer (A) and the cross-linking agent (B) in the non-volatile component is 50% by mass or more.
• ⁇ 14> A copolymer dispersion used for preparing the pressure-sensitive adhesive composition according to any one of ⁇ 1> to ⁇ 13>.
• the copolymer (A) includes a structural unit derived from the monomer (a1), a structural unit derived from the monomer (a2) having a carboxy group, and a structural unit derived from the monomer (a3) having an alkoxysilyl group.
• the monomer (a1) comprises either or both of a (meth) acrylic acid alkyl ester having only one ethylenically unsaturated bond and a hydrocarbon having only one ethylenically unsaturated bond.
• the content of the structural unit derived from the monomer (a2) in the copolymer (A) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 1.0 part by mass or more and 12 parts by mass or less.
• the content of the structural unit derived from the monomer (a3) in the copolymer (A) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 0.010 parts by mass or more and 3.5 parts by mass or less.
• the copolymer dispersion liquid contains the copolymer (A) and an aqueous medium, and contains the copolymer (A) and an aqueous medium.
• the copolymer (A) includes a structural unit derived from the monomer (a1), a structural unit derived from the monomer (a2) having a carboxy group, and a structural unit derived from the monomer (a3) having an alkoxysilyl group.
• the monomer (a1) comprises either or both of a (meth) acrylic acid alkyl ester having only one ethylenically unsaturated bond and a hydrocarbon having only one ethylenically unsaturated bond.
• the content of the structural unit derived from the monomer (a2) in the copolymer (A) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 1.0 part by mass or more and 12 parts by mass or less.
• the content of the structural unit derived from the monomer (a3) in the copolymer (A) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 0.010 parts by mass or more and 3.5 parts by mass or less.
• the cross-linking agent (B) contains one or more selected from the group consisting of a polycarbodiimide compound, a polyepoxy compound, and a polyisocyanate compound.
• a set in which the content of the cross-linking agent (B) with respect to 100 parts by mass of the copolymer (A) is 0.010 parts by mass or more and 10 parts by mass or less.
• An adhesive tape comprising a base material and an adhesive layer formed on the surface of the base material.
• the adhesive layer is an adhesive tape containing a cured product of the adhesive composition according to any one of ⁇ 1> to ⁇ 13>.
• ⁇ 18> The step of applying the pressure-sensitive adhesive composition according to any one of ⁇ 1> to ⁇ 13> to the base material, and A method for producing an adhesive tape, which comprises a step of removing an aqueous medium from the pressure-sensitive adhesive composition applied to the substrate to form a pressure-sensitive adhesive layer.
• the adhesive force is defined as "the force generated by the contact between the adhesive surface of the adhesive sheet or the adhesive tape and the adherend", and means the force required when peeling off the pasted material.
• the holding force is defined as "the force with which the adhesive can withstand the displacement when the adhesive sheet or the adhesive tape is attached to the adherend and a static load is applied in the length direction", and the cohesion of the adhesive layer is defined. Represents the strength of power.
• an adhesive tape that exhibits strong adhesive force not only at room temperature but also at high temperature and also has high holding power at high temperature.
• the surface means "hail noodles”.
• (Meta) acrylic is a general term for acrylic and methacrylic
• (meth) acrylate is a general term for acrylate and methacrylate.
• Ethylene unsaturated bond refers to an ethylenically unsaturated bond having radical polymerization unless otherwise specified.
• the structural unit derived from the compound having a certain ethylenically unsaturated bond is the chemical structure of the portion other than the ethylenically unsaturated bond of the compound and its structure in the polymer. It is assumed that the chemical structure of the part other than the part corresponding to the ethylenically unsaturated bond of the unit is the same.
• the structural unit derived from acrylic acid has a structure represented by -CH 2 CH (COOH)-in the polymer.
• the compound from which a certain structural unit is derived refers to the compound having the above-mentioned relationship with the structural unit, and does not have to match the monomer used in the actual manufacturing process.
• structural units having an ionic functional group such as a carboxy group are the same regardless of whether a part of the functional group is ion-exchanged or not ion-exchanged. It is a structural unit derived from an ionic compound.
• the structural unit represented by ⁇ CH 2 C (CH 3 ) (COONa) ⁇ is also a structural unit derived from methacrylic acid.
• an ethylenically unsaturated bond may remain as a structural unit of the polymer.
• a plurality of independent ethylenically unsaturated bonds are a plurality of ethylenically unsaturated bonds that do not form conjugated diene with each other.
• the structural unit derived from divinylbenzene may be a structure having no ethylenically unsaturated bond (a form in which a portion corresponding to any ethylenically unsaturated bond is incorporated into a polymer chain). It may have a structure having an ethylenically unsaturated bond (a form in which only the portion corresponding to one of the ethylenically unsaturated bonds is incorporated into the polymer chain).
• a portion other than the chain corresponding to the ethylenically unsaturated bond for example, a functional group such as a carboxy group, a hydroxy group, an alkoxysilyl group, or an epoxy group is chemically reacted to introduce an ester structure or another functional group.
• a functional group such as a carboxy group, a hydroxy group, an alkoxysilyl group, or an epoxy group
• the chemical structure after the reaction is used as a reference.
• the saponified structural unit is not a structural unit derived from vinyl acetate but a structural unit derived from vinyl alcohol, considering the chemical structure of the polymer as a standard. do.
• the chemical structure of the structural unit derived from the monomer (a3) having an alkoxysilyl group after polymerization and obtained by the chemical reaction of the alkoxysilyl group is the structural unit derived from the monomer (a3) having an alkoxysilyl group.
• the “nonvolatile component” is a component remaining after weighing 1 g of the composition in an aluminum dish having a diameter of 5 cm and drying at 105 ° C. for 1 hour while circulating air in a dryer at 1 atm (1013 hPa).
• the form of the composition includes, but is not limited to, a solution, a dispersion, and a slurry.
• the “nonvolatile content concentration” is the mass ratio (mass%) of the non-volatile content after drying under the above conditions with respect to the mass (1 g) of the composition before drying.
• the term "adhesive" means a cured product of the pressure-sensitive adhesive composition, that is, an article obtained by removing water from the pressure-sensitive adhesive composition and curing the product.
• the pressure-sensitive adhesive is obtained by curing the pressure-sensitive adhesive composition in one embodiment by drying the pressure-sensitive adhesive composition at 100 ° C. for 3 minutes and then allowing it to stand at 40 ° C. for 3 days. It is considered that the cross-linking reaction of the pressure-sensitive adhesive composition is completed while standing at 40 ° C. for 3 days.
• the "adhesive composition coating layer” refers to a base material or the like by removing an aqueous medium from the pressure-sensitive adhesive composition coated on a base material or a release paper (hereinafter, a base material or the like). Means the layer formed in.
• the pressure-sensitive adhesive composition coating layer can be cured to obtain a pressure-sensitive adhesive layer.
• the pressure-sensitive adhesive layer is obtained by curing the pressure-sensitive adhesive composition-coated layer by allowing it to stand at 40 ° C. for 3 days.
• the adhesive layer is a layer formed by curing a pressure-sensitive adhesive composition-coated layer formed on a release paper by transferring it to a substrate such as a non-woven fabric and then allowing it to stand at 40 ° C. for 3 days. May be.
• the pressure-sensitive adhesive composition according to this embodiment contains a copolymer (A), a cross-linking agent (B), and an aqueous medium.
• the pressure-sensitive adhesive composition may contain other additives and the like.
• the copolymer (A) is a polymer of a compound having an ethylenically unsaturated bond.
• the copolymer (A) is a structural unit derived from a monomer (a1) described later, a structural unit derived from a monomer (a2) having a carboxy group, and a structural unit derived from a monomer (a3) having an alkoxysilyl group. And include.
• the copolymer (A) preferably contains at least one of a structural unit derived from the monomer (a4) having a hydroxy group and a structure derived from another compound (a6) such as a chain transfer agent. , It is more preferable to include both.
• the copolymer (A) may contain structural units derived from other monomers (a5) that do not fall under any of the monomers (a1) to (a4).
• the copolymer (A) does not have a structural unit derived from a compound having a plurality of independent ethylenically unsaturated bonds.
• the compound having a plurality of independent ethylenically unsaturated bonds include divinylbenzene and ethylene glycol dimethacrylate.
• the monomer (a1) consists of (meth) acrylic acid alkyl ester and / or a hydrocarbon having an ethylenically unsaturated bond.
• the monomer (a1) has only one ethylenically unsaturated bond.
• the monomer (a1) preferably contains a (meth) acrylic acid alkyl ester, and more preferably consists of a (meth) acrylic acid alkyl ester.
• the monomer (a1) may contain one kind of compound or may contain two or more kinds of compounds.
• examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) crylate, and tert-butyl ( Examples thereof include meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and isoboronyl (meth) acrylate.
• methyl (meth) acrylate, n-butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate are preferable because the physical properties can be easily controlled.
• hydrocarbon having an ethylenically unsaturated bond examples include styrene, ⁇ -methylstyrene, p-methylstyrene, ethylene, and propylene.
• styrene which easily generates radicals, is preferable as the hydrocarbon having an ethylenically unsaturated bond.
• the glass transition point of the copolymer (A) can be adjusted by the type and the ratio thereof contained in the structural unit derived from the monomer (a1).
• the structural unit for lowering the glass transition point of the copolymer (A) include, but are not limited to, a structural unit derived from 2-ethylhexyl acrylate and a structural unit derived from butyl acrylate.
• the structural unit for increasing the glass transition point of the copolymer (A) include, but are not limited to, a structural unit derived from methyl methacrylate and a structural unit derived from styrene.
• the monomer (a2) has a carboxy group.
• the monomer having an alkoxysilyl group that is, the monomer corresponding to the definition of the monomer (a3)
• having the carboxy group corresponds to the monomer (a3) and is the monomer (a2).
• the carboxy group may partially or completely form a salt, but the salt formation ratio is preferably 10% or less based on the number (mol number).
• the monomer (a2) preferably does not have a plurality of independent ethylenically unsaturated bonds.
• the monomer (a2) is preferably a compound having an ethylenically unsaturated bond and a carboxy group.
• Examples of compounds having an ethylenically unsaturated bond and a carboxy group include acrylic acid, methacrylic acid, crotonic acid, citraconic acid, itaconic acid, maleic acid, maleic anhydride, fumaric acid, 2-carboxyethyl acrylate oligomer, and 2-acryloyl.
• ⁇ , ⁇ -unsaturated mono or dicarboxylic acids such as oxyethyl succinic acid
• carboxyl group-containing vinyl compounds such as monohydroxyethyl (meth) phthalate and monohydroxypropyl (meth) acrylate; etc. are preferable.
• the monomer (a2) may contain one kind of compound or may contain two or more kinds of compounds.
• the monomer (a2) is preferably (meth) acrylic acid, and more preferably composed of (meth) acrylic acid.
• the mechanism for improving heat resistance by using the monomer (a2) having a carboxy group is not clear, but the present inventors presume that it is due to the following mechanism. That is, the carboxy group of the structural unit derived from the monomer (a2) reacts with the functional group of the cross-linking agent (B) described later to form an intermolecular cross-link (external cross-link), and these cross-links aggregate in the adhesive layer. It is presumed that the force is applied and the heat resistance of the adhesive layer is improved.
• the monomer (a3) has an alkoxysilyl group.
• the monomer (a3) preferably does not have a plurality of independent ethylenically unsaturated bonds, and more preferably has only one ethylenically unsaturated bond.
• the total content of the dialkoxysilyl group and the trialkoxysilyl group in the total alkoxysilyl group contained in the copolymer (A) is preferably 80 mol% or more, more preferably 90 mol% or more, and more preferably 100 mol. % Is more preferable.
• the content of the trialkoxysilyl group in the total alkoxysilyl group contained in the copolymer (A) is preferably 70 mol% or more, more preferably 80 mol% or more, and more preferably 90 mol% or more. It is more preferably 100 mol%, and particularly preferably 100 mol%. This is because the crosslink density inside the copolymer (A) is improved and the heat resistance of the adhesive layer is increased.
• the oxygen atom bonded to the silicon atom contained in the alkoxysilyl group and the alkyl group bonded via the oxygen atom are collectively referred to as "alkoxy group contained in the alkoxysilyl group".
• the trialkoxysilyl group contains three alkoxy groups.
• the total content of the ethoxy group and the methoxy group is preferably 70 mol% or more, more preferably 80 mol% or more. It is more preferably 90 mol% or more, and particularly preferably 100 mol%. This is because the reactivity of the alkoxysilyl group is improved and the crosslink density inside the copolymer (A) can be easily adjusted by the amount of the alkoxysilyl group.
• the monomer (a3) is preferably a compound having an ethylenically unsaturated bond and an alkoxysilyl group.
• a compound represented by the following general formula (1) is preferably mentioned.
• R 1 represents a methacryloxy group, an acryloxy group or a vinyl group
• R 2 to R 4 each independently have an alkoxy group having 1 to 20 carbon atoms or an alkyl group having 1 to 20 carbon atoms.
• at least one of R 2 to R 4 is an alkoxy group having 1 to 20 carbon atoms.
• n represents an integer from 0 to 20.
• n is preferably 1 to 10, more preferably 1 to 5.
• the alkoxy group having 1 to 20 carbon atoms preferably has 1 to 8 carbon atoms, more preferably 1 to 3 carbon atoms, and particularly preferably 1 or 2 carbon atoms.
• the number of carbon atoms of the alkyl group having 1 to 20 carbon atoms is preferably 1 to 8 carbon atoms, more preferably 1 to 3 carbon atoms, and particularly preferably 1 or 2 carbon atoms.
• Examples of the alkoxy group having 1 to 20 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, an octoxy group and the like.
• alkyl group having 1 to 20 carbon atoms examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, a 2-ethylhexyl group, a decyl group and a dodecyl group.
• alkyl group having 1 to 20 carbon atoms examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, a 2-ethylhexyl group, a decyl group and a dodecyl group.
• Examples thereof include a tetradecyl group, a hexadecyl group and an octadec
• Examples of the monomer represented by the general formula (1) include ⁇ and ⁇ -ethylene having a hydrolyzable alkoxysilyl group such as vinyltriethoxysilane, vinyltris ( ⁇ -methoxyethoxy) silane, and 3-methacryloxypropyltrimethoxysilane. Sexually unsaturated compounds are preferred.
• Examples of the 3-methacryloxypropyltrimethoxysilane include "KBM-503" manufactured by Shin-Etsu Chemical Co., Ltd.
• the monomer (a3) may contain only one kind of compound, or may contain two or more kinds of compounds.
• the monomer (a4) has a hydroxy group.
• the monomer having an alkoxysilyl group that is, the monomer corresponding to the definition of the monomer (a3)
• having a hydroxy group corresponds to the monomer (a3) and is the monomer (a4). Is not applicable.
• the holding power of the adhesive layer at a high temperature is further improved.
• This mechanism is not clear, but the present inventors presume that it is due to the following mechanism. That is, the hydroxy group of the structural unit derived from the monomer (a4) reacts with the alkoxysilyl group of the structural unit derived from the monomer (a3) to form an intramolecular crosslink (internal crosslink), and / or the monomer ( The hydroxy group of the structural unit derived from a4) assists in forming an intermolecular crosslink (external crosslink) by reacting with the functional group of the crosslinker (B) described later, and these crosslinks at a high temperature of the adhesive layer.
• the compound from which the monomer (a4) is derived preferably does not have a plurality of independent ethylenically unsaturated bonds, and more preferably has only one ethylenically unsaturated bond.
• the monomer (a4) is preferably a compound having an ethylenically unsaturated bond and a hydroxy group.
• the monomer (a4) is preferably a (meth) acrylate having a hydroxy group, and more preferably an alkyl (meth) acrylate having a hydroxy group, that is, a hydroxyalkyl (meth) acrylate.
• Examples of the monomer (a4) include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate. Among these, 2-hydroxyethyl (meth) acrylate is more preferable, and 2-hydroxyethyl methacrylate is further preferable.
• the monomer (a4) may contain only one kind of compound, or may contain two or more kinds of compounds.
• the monomer (a5) is a compound having an ethylenically unsaturated bond, and does not fall under any of the monomers (a1) to (a4).
• Examples of the monomer (a5) include alkylamino (meth) acrylates such as N, N-dimethylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate; vinyl formate, vinyl acetate, vinyl propionate, and versatic.
• alkylamino (meth) acrylates such as N, N-dimethylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate
• vinyl formate vinyl acetate, vinyl propionate, and versatic.
• Vinyl ester compounds such as vinyl acid acid; conjugated diolefin compounds such as butadiene, isoprene and chloroprene; amineimide group-containing vinyl compounds such as 1,1,1-trimethylaminemethacrylimide; vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; (Meta) acrylamide compounds such as meta) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide; allyl sulfonate, p-styrene sulfonic acid Radical-polymerizable UV absorbers such as 2- (2'-hydroxy-5'-methacryloyloxyethylphenyl) -2H-benzotriazole; and 1 , 2, 2, 6, 6-Pentamethyl-4-piperidyl methacrylate and the like, which have radical polymerizable properties.
• the term "other compound (a6)” refers to a structure or structure excluding structural units derived from the monomers (a1) to (a5) among the structural or structural units constituting the copolymer (A).
• the compound (a6) include a polymerization initiator and a chain transfer agent used in the synthesis step of the copolymer (A).
• the other compound (a6) unlike the monomers (a1) to (a5), the structure of the compound such as the polymerization initiator and the chain transfer agent and the other compound (a6) in the copolymer (A). ) And the above-mentioned correspondence may not be necessary.
• the content of the structural unit derived from the compound such as each monomer and the chain transfer agent in the present embodiment can be calculated by using the blending amount of each compound added for the production of the copolymer (A).
• the copolymer (A) preferably contains a total of 90% by mass or more of structural units derived from the monomer (a1), structural units derived from the monomer (a2), and structural units derived from the monomer (a3). It is more preferably contained in an amount of 95% by mass or more, and further preferably contained in an amount of 97% by mass or more. This is to suppress an increase in the glass transition point of the copolymer (A) and improve the tackiness, wettability, and adhesion of the adhesive layer.
• the content of the structural unit derived from the monomer (a2) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 1.0 part by mass or more, preferably 2.0 parts by mass or more, 3 It is more preferable that the content is 0.0 parts by mass or more. This is to improve the cohesive force of the adhesive layer and enhance the heat resistance.
• the content of the structural unit derived from the monomer (a2) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 12 parts by mass or less, preferably 8.0 parts by mass or less, preferably 6.0. It is more preferably less than the mass part. This is because the polarity of the copolymer (A) and the cohesive force of the adhesive layer are appropriately maintained, and an adhesive layer having high adhesiveness can be obtained.
• the content of the structural unit derived from the monomer (a3) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 0.010 parts by mass or more, more preferably 0.020 parts by mass or more. It is more preferably 0.030 parts by mass or more. This is to improve the cohesive force of the adhesive layer and enhance the heat resistance.
• the content of the structural unit derived from the monomer (a3) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is 3.5 parts by mass or less, preferably 2.0 parts by mass or less. It is more preferably 2 parts by mass or less, further preferably 0.60 parts by mass or less, further preferably 0.12 parts by mass or less, and particularly preferably 0.060 parts by mass or less. .. This is because an adhesive layer having high adhesiveness can be obtained by maintaining an appropriate cohesive force of the adhesive layer.
• the content of the structural unit derived from the monomer (a4) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is preferably 0.10 parts by mass or more, and preferably 0.20 parts by mass or more. It is more preferably 0.30 part by mass or more, and further preferably 0.30 part by mass or more. This is because the holding power of the adhesive layer in a high temperature environment is improved.
• the content of the structural unit derived from the monomer (a4) with respect to 100 parts by mass of the structural unit derived from the monomer (a1) is preferably 10 parts by mass or less, more preferably 5.0 parts by mass or less. , 1.5 parts by mass or less, and particularly preferably 0.60 parts by mass or less. This is to obtain an adhesive layer having sufficient adhesiveness by appropriately maintaining the polarity of the copolymer (A) and the cohesive force of the adhesive layer.
• the glass transition point (Tg) of the copolymer (A) is preferably ⁇ 80 ° C. or higher, more preferably ⁇ 65 ° C. or higher, and even more preferably ⁇ 55 ° C. or higher. This is to improve the cohesive force of the pressure-sensitive adhesive and impart more excellent heat resistance to the pressure-sensitive adhesive layer.
• the glass transition point of the copolymer (A) is preferably 30 ° C. or lower, more preferably 0 ° C. or lower, further preferably ⁇ 20 ° C. or lower, and preferably ⁇ 35 ° C. or lower. Especially preferable. This is to improve the wettability of the pressure-sensitive adhesive composition described later and to improve the adhesion of the pressure-sensitive adhesive layer to the substrate. This is also to increase the flexibility of the adhesive layer and improve the tackiness of the adhesive layer during dry use.
• the method for producing the copolymer (A) is not particularly limited, but the compound from which each structural unit constituting the copolymer (A) is derived may be polymerized as a monomer, and some or all the structural units may be polymerized. After polymerizing other compounds, it may be used as a target structural unit by introducing a functional group or the like.
• Examples of the method for producing the copolymer (A) include a method in which a monomer is emulsified in an aqueous medium and then emulsion-polymerized using a polymerization initiator.
• a chain transfer agent may be used to control the molecular weight of the copolymer and its distribution within an appropriate range.
• An emulsifier may be used to emulsify the monomer.
• the monomer may be charged in full in the reactor in advance, and in order to obtain uniform particles, a mixture containing all kinds of monomers for forming the structural unit of the copolymer (A) may be continuously or intermittently prepared. It may be polymerized while being supplied and charged.
• the polymerization temperature is not particularly limited, but is preferably 5 to 100 ° C, more preferably 50 to 90 ° C.
• the aqueous medium is water, a hydrophilic solvent, or a mixture thereof.
• the hydrophilic solvent include methanol, ethanol, isopropyl alcohol, N-methylpyrrolidone and the like.
• the aqueous medium is preferably water.
• a water to which a hydrophilic solvent is added may be used as long as the polymerization stability is not impaired.
• polymerization initiator used in the emulsion polymerization examples include persulfate-based initiators such as potassium persulfate and ammonium persulfate, and water-soluble azo-based initiators such as 2,2'-azobis (2-methylpropionamidine) dihydrochloride. Examples thereof include agents, organic peroxides such as t-butyl hydroperoxide and cumene hydroperoxide, hydrogen peroxide and the like. These polymerization initiators may be used alone or in combination.
• the amount of the polymerization initiator used is preferably 0.1 to 2% by mass with respect to the total amount of the monomers.
• a reducing agent can be used together with these polymerization initiators.
• reducing agents include reducing organic compounds such as ascorbic acid, tartaric acid, citric acid, glucose, and formaldehyde sulfoxylate metal salts, and reducing properties such as sodium thiosulfate, sodium sulfite, sodium bisulfate, and sodium metabisulfate. Inorganic compounds and the like can be mentioned.
• chain transfer agent examples include n-dodecyl mercaptan, tert-dodecyl mercaptan, n-butyl mercaptan, 2-ethylhexylthioglycolate, 2-mercaptoethanol, ⁇ -mercaptopropionic acid, methyl alcohol, n-propyl alcohol and isopropyl.
• chain transfer agent examples include, but are not limited to, alcohols, t-butyl alcohols, benzyl alcohols and the like. Only one type of chain transfer agent may be used, or two or more types may be used.
• the amount of the chain transfer agent used is preferably 0.0010 part by mass or more, preferably 0.050 part by mass, based on 100 parts by mass of the total amount of each monomer from which each structural unit is derived in the copolymer (A).
• the above is more preferable, and 0.080 parts by mass or more is further preferable. This is to form an adhesive layer having a strong adhesive force.
• the amount of the chain transfer agent used is preferably 5.0 parts by mass or less, preferably 2.0 parts by mass, based on 100 parts by mass of the total amount of each monomer from which each structural unit is derived in the copolymer (A).
• the amount is more preferably 0.50 parts by mass or less, further preferably 0.20 parts by mass or less, and particularly preferably 0.20 parts by mass or less. This is to improve the heat resistance of the adhesive layer.
• the emulsifier is not particularly limited, but specifically, an anionic surfactant such as sodium dodecylbenzene sulfonate and sodium dodecyl sulfate, and a nonionic surfactant such as polyoxyethylene alkyl ether and polyoxyethylene nonylphenyl ether. , Cationic surfactants such as diarrhealtrimethylammonium bromide and laurylpyridinium chloride, amphoteric surfactants such as laurylbedine, and other reactive surfactants. These surfactants may be used alone or in combination of two or more.
• the epoxy group may be a part of the glycidyl group.
• the cross-linking agent (B) may be a carbodiimide compound having an epoxy group. Of these, polycarbodiimide compounds and polyepoxy compounds are particularly preferable because they can impart high adhesive force and cohesive force to the pressure-sensitive adhesive.
• the cross-linking agent (B) is preferably a water-soluble or water-dispersible compound.
• polycarbodiimide compound examples include p-phenylene-bis (2,6-kisilylcarbodiimide), tetramethylene-bis (t-butylcarbodiimide), cyclohexane-1,4-bis (methylene-t-butylcarbodiimide) and the like.
• Carbodilite registered trademark, the same applies hereinafter
• V-02 "Carbodilite SV-02"
• Carbodilite V-04 Carbodilite V-10
• Carbodilite E-02 manufactured by Nisshinbo Chemical Co., Ltd.
• Examples thereof include “carbodilite E-03A” and "carbodilite E-05".
• the carbodiimide equivalent (molecular weight per carbodiimide group) of the polycarbodiimide compound is preferably 150 or more, more preferably 250 or more, further preferably 300 or more, and more preferably 350 or more. Especially preferable. This is to suppress steric hindrance in the crosslinking reaction with the copolymer (A) and improve the rate and crosslinking density of the crosslinking reaction.
• the carbodiimide equivalent (molecular weight per carbodiimide group) of the polycarbodiimide compound is preferably 1000 or less, more preferably 750 or less, and further preferably 600 or less. This is to improve the crosslinking density in the crosslinking reaction with the copolymer (A).
• polyepoxy compound examples include bisphenol A / epichlorohydrin type epoxy resin and sorbitol polyglycidyl ether (for example, “Denacol (registered trademark, the same applies hereinafter) EX-611” and “Denacol EX-612” manufactured by Nagase ChemteX Corporation. , "Denacol EX-614", “Denacol EX-614B”, “Denacol EX-622”, etc.), Polyglycerol polyglycidyl ether (for example, “Denacol EX-512", “Denacol EX-521” manufactured by Nagase ChemteX Corporation.
• Bisphenol A / epichlorohydrin type epoxy resin and sorbitol polyglycidyl ether for example, “Denacol (registered trademark, the same applies hereinafter) EX-611” and “Denacol EX-612” manufactured by Nagase ChemteX Corporation. ,
• Pentaerythritol polyglycidyl ether for example, “Denacol EX-411” manufactured by Nagase Chemtex
• Diglycerol polyglycidyl ether for example, “Denacol EX-421” manufactured by Nagase Chemtex
• Gglycerol polyglycidyl ether eg, "Denacol EX-313", “Denacol EX-314", etc. manufactured by Nagase Chemtex
• Trimethylol Propanepolyglycidyl ether for example, "Denacol EX-321” manufactured by Nagase Chemtex
• Resocinol diglycidyl ether for example, "Denacol EX-201” manufactured by Nagase Chemtex Co., Ltd.
• Neopentyl glycol diglycidyl ether for example, "Denacol EX-211” manufactured by Nagase Chemtex Co., Ltd.
• 1,6-Hexanediol diglycidyl ether eg, "Denacol EX-212" manufactured by Nagase Chemtex
• Hydrogenerated bisphenol A diglycidyl ether eg, "Denacol EX-” manufactured by Nagase Chemtex.
• Ethylene glycol diglycidyl ether eg,“ Denacol EX-810 ”,“ Denacol EX-811 ”, etc. manufactured by Nagase Chemtex
• Diethylene glycol diglycidyl ether eg,“ Denacol “manufactured by Nagase Chemtex).
• EX-850 "Denacol EX-851”, etc.
• Polyethylene glycol diglycidyl ether for example, “Denacol EX-821", “Denacol EX-830", “Denacol EX-832", “Denacol EX-832” manufactured by Nagase ChemteX Corporation.
• "Denacol EX-941", “Denacol EX-920", “Denacol EX-931”, etc.) diglycidyl aniline, diglycidylamine, N, N, N', N'-tetraglycidyl m-xylene manufactured by Sechemtex. Examples thereof include diamine, 1,3-bis (N, N'-diglycidylaminomethyl) cyclohexane and the like. Of these, the water-soluble type is preferable.
• the epoxy equivalent (molecular weight per epoxy group) of the polyepoxy compound is preferably 70 or more, and more preferably 100 or more. This is to suppress steric hindrance in the crosslinking reaction with the copolymer (A) and improve the rate and crosslinking density of the crosslinking reaction.
• the epoxy equivalent (molecular weight per epoxy group) of the polyepoxy compound is preferably 700 or less, more preferably 400 or less, further preferably 300 or less, and preferably 200 or less. Especially preferable. This is to improve the crosslinking density in the crosslinking reaction with the copolymer (A).
• polyisocyanate compound examples include toluylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, metaxylylene diisocyanate, 1,5-naphthalenedi isocyanate, hydride diphenylmethane diisocyanate, and hydride tolylene diisocyanate. , Hydroxylylene diisocyanate, isophorone diisocyanate, tetramethylxylylene diisocyanate and the like.
• burette polyisocyanate compounds such as "Sumijour N” (manufactured by Sumitomo Bayer Urethane); "Death Module IL”, “Death Module HL” (manufactured by Bayer AG), and “Coronate”.
• Polyisocyanate compounds with isocyanurate rings such as “EH” (manufactured by Nippon Urethane); Adduct polyisocyanate compounds such as "Sumijour L” (manufactured by Sumitomo Bayer Urethane) and “Coronate HL” (manufactured by Nippon Polyurethane).
• Examples thereof include self-emulsifying water-dispersed polyisocyanate compounds such as "Aquanate 100", “Aquanate 110", “Aquanate 200”, and “Aquanate 210" (manufactured by Nippon Polyurethane Co., Ltd.). Of these, a water-dispersed polyisocyanate compound is preferable. Further, a blocked isocyanate compound may be used as the polyisocyanate compound.
• the isocyanato equivalent (molecular weight per isocyanato group) of the polyisocyanate compound is preferably 60 or more, more preferably 75 or more. This is to suppress steric hindrance in the crosslinking reaction with the copolymer (A) and improve the rate and crosslinking density of the crosslinking reaction.
• the isocyanato equivalent (molecular weight per isocyanato group) of the polyisocyanate compound is preferably 500 or less, more preferably 200 or less, and further preferably 100 or less. This is to improve the crosslinking density in the crosslinking reaction with the copolymer (A).
• the content of the cross-linking agent (B) with respect to 100 parts by mass of the copolymer (A) is 0.010 parts by mass or more, preferably 0.020 parts by mass or more, preferably 0.050 parts. It is more preferably 0 parts by mass or more, further preferably 0.15 parts by mass or more, and particularly preferably 0.40 parts by mass or more. This is because the crosslink density between the particles is increased, the cohesive force of the pressure-sensitive adhesive is improved, and the strength of the pressure-sensitive adhesive layer is improved.
• the content of the cross-linking agent (B) with respect to 100 parts by mass of the copolymer (A) is 10 parts by mass or less, preferably 5.0 parts by mass or less, preferably 3.0 parts by mass. It is more preferably less than or equal to 1.0 part by mass or less. This is because the flexibility of the adhesive layer is improved and stronger adhesive force can be obtained.
• the aqueous medium is water, a hydrophilic solvent, or a mixture thereof.
• the hydrophilic solvent include methanol, ethanol, isopropyl alcohol, N-methylpyrrolidone and the like.
• the aqueous medium is preferably water.
• the aqueous medium may have the same composition as the aqueous solvent used for the polymerization of the copolymer (A), or may have a different composition.
• Additives can be optionally included in the pressure-sensitive adhesive composition.
• the timing of adding the additive is not particularly limited.
• the additive can be added simultaneously with or after mixing the copolymer (A) and the cross-linking agent (B). Further, the additive may be added to either or both solutions or dispersions in advance before mixing the copolymer (A) and the cross-linking agent (B). Examples of the additive include a pH adjuster, a tackifier and the like.
• a plasticizer, an antioxidant, a filler, a pigment, a colorant, a wetting agent, an antifoaming agent, a thickener and the like can be appropriately used.
• a general acidic substance such as an inorganic acid or an organic acid, a salt thereof, or an amphoteric salt such as an amino acid
• examples of the pH adjuster for organic acids include acetic acid, formic acid, glycolic acid, malic acid, citric acid, maleic acid, fumaric acid, malonic acid, phthalic acid, isophthalic acid, lactic acid, butyric acid, ascorbic acid, succinic acid and tartrate acid.
• Examples of the pH adjuster for the inorganic acid include boric acid, phosphoric acid, hydrochloric acid, nitric acid, nitrite, sulfuric acid, and sulfurous acid.
• examples of the salt of the acidic substance include salts of the above-mentioned organic acid or inorganic acid with sodium, potassium, ammonia, aminoethanol, diethanolamine, triethanolamine and the like.
• examples of the amino acid pH adjuster include glycine, glycylglycine, aspartic acid, aspartic acid, alanine, phenylalanine, arginine, glutamine, and glutamic acid. These pH regulators can be used alone or in combination of two or more.
• tackifier examples include rosin resin, rosin ester resin, hydrogenated rosin resin, polymerized rosin resin, ⁇ -pinene resin, ⁇ -pinene resin, terpene phenol resin, C5 distillate petroleum resin, and C9 distillate petroleum.
• examples thereof include resins, C5 and C9 distillate petroleum resins, dicyclopentadiene petroleum resins, alkylphenol resins, xylene resins, kumaron resins, kumaron inden resins and the like.
• the tackifier can be used alone or in combination of two or more.
• the non-volatile content concentration of the pressure-sensitive adhesive composition is preferably 20% by mass or more, more preferably 30% by mass or more, and further preferably 40% by mass or more. This is because a larger amount of the pressure-sensitive adhesive layer can be formed with a small amount of the pressure-sensitive adhesive composition applied. Further, the drying time of the applied pressure-sensitive adhesive composition is shortened, and the productivity is improved.
• the non-volatile content concentration of the pressure-sensitive adhesive composition is preferably 75% by mass or less, more preferably 65% by mass or less. This is to suppress gelation of the copolymer (A) in the pressure-sensitive adhesive composition.
• the total content of the copolymer (A) and the cross-linking agent (B) in the non-volatile component in the pressure-sensitive adhesive composition is preferably 50% by mass or more, more preferably 60% by mass or more, and 70% by mass. % Or more is more preferable. This is because the adhesive strength and holding power of the adhesive layer, particularly the holding power at high temperature, are improved.
• the total content of the copolymer (A) and the cross-linking agent (B) in the non-volatile component in the pressure-sensitive adhesive composition is preferably 90% by mass or less, more preferably 80% by mass or less.
• the pressure-sensitive adhesive composition of the present embodiment may be stored as a set of a plurality of agents in which the constituent components are divided into a plurality of additives.
• the copolymer dispersion liquid containing the copolymer (A) and the aqueous medium and the cross-linking agent (B) are prepared as a set, and when the pressure-sensitive adhesive composition is used, the copolymer dispersion liquid and the copolymer dispersion liquid are used.
• the pressure-sensitive adhesive composition can also be prepared by mixing the cross-linking agent (B).
• Adhesive tape is a typical use of the pressure-sensitive adhesive composition according to the present invention.
• the adhesive tape according to the present embodiment includes a base material and an adhesive layer formed on the surface of the base material.
• the adhesive layer may be formed on only one surface of the substrate, or may be formed on both surfaces. Further, in the adhesive tape of the present invention, the adhesive layer may be protected by a known release liner such as a release paper or a release PET.
• the material of the base material is not particularly limited, but examples thereof include paper, plastic, cloth, and metal.
• the base material may be a film, a woven fabric, or a non-woven fabric, and is not particularly limited, but is preferably a non-woven fabric. This is because the pressure-sensitive adhesive composition soaks into the base material and the bonding force between the pressure-sensitive adhesive layer and the base material is enhanced.
• the "base material" in the present invention is a portion to be attached to the adherend together with the adhesive layer when the adhesive tape of the present invention is used, that is, attached to the adherend, and is peeled off when the adhesive tape is used. It does not include release liners such as release paper.
• the pressure-sensitive adhesive layer contains a pressure-sensitive adhesive that is a cured product of the pressure-sensitive adhesive composition.
• the pressure-sensitive adhesive layer may contain additives and the like contained in the pressure-sensitive adhesive composition.
• the adhesive layer contains a non-volatile component of the adhesive composition.
• the thickness of the adhesive layer is preferably 10 ⁇ m or more, more preferably 30 ⁇ m or more, and even more preferably 50 ⁇ m or more. This is because the adhesive layer can be sufficiently deformed to follow the surface of the adherend.
• the thickness of the adhesive layer is preferably 200 ⁇ m or less, more preferably 100 ⁇ m or less. This is to suppress the cohesive failure of the adhesive layer.
• the adhesive layer may include two or more adhesive layers. Further, the adhesive tape of the present invention may be provided with other layers (for example, an intermediate layer, an undercoat layer, etc.) in addition to the base material and the adhesive layer as long as the effects of the present invention are not impaired.
• the method for producing the adhesive tape includes a step of applying the pressure-sensitive adhesive composition to one or both sides of the base material and a step of removing an aqueous medium from the pressure-sensitive adhesive composition applied to the base material to form a pressure-sensitive adhesive layer.
• an aqueous medium, a thickener, or the like may be appropriately added to the pressure-sensitive adhesive composition in order to adjust the viscosity of the pressure-sensitive adhesive composition.
• the pressure-sensitive adhesive composition When the pressure-sensitive adhesive composition is applied to both sides, it may be applied one side at a time, or may be applied to both sides at once.
• the pressure-sensitive adhesive composition may be continuously applied to the substrate or may be applied intermittently.
• the amount of the pressure-sensitive adhesive composition applied is not particularly limited, but is preferably 10 to 500 g / m 2 .
• the drying temperature of the pressure-sensitive adhesive composition applied to the substrate is not particularly limited, but is preferably 20 to 160 ° C. This is because an adhesive layer having sufficient adhesive force and cohesive force can be obtained.
• the adhesive tape has been described as one of the preferred uses of the pressure-sensitive adhesive composition of the present invention, but the use of the pressure-sensitive adhesive composition of the present invention is not limited to this.
• the pressure-sensitive adhesive composition of the present invention may be applied directly to a member and bonded to another member without using an adhesive tape.
• the use of the adhesive tape and the adhesive method characterized by using the adhesive tape for example, there are applications such as electric appliances, automobiles, building members, toys and the like.
• the adherend of the adhesive tape is not particularly limited, but a plastic member such as polypropylene or a metal member such as SUS or aluminum is particularly useful.
• a monomer emulsified solution containing 50 parts by mass of ion-exchanged water, 1.0 part by mass of an emulsifier, and a total of 100 parts by mass of a monomer and a chain transfer agent was added to the above-mentioned mixed solution to which the polymerization initiator was added over 4 hours. Dropped.
• the types of the monomers and chain transfer agents dropped here are as shown in Table 1, Table 2-1 and Table 2-2 in each Example and Comparative Example.
• the content of each component in 100 parts by mass of the total of the monomer and the chain transfer agent dropped here is as shown in the left column of each Example and Comparative Example of Table 1, Table 2-1 and Table 2-2. be.
• the amount of the monomer and the chain transfer agent dropped here with respect to 100 parts by mass of the monomer (a1) is as shown in the right column of each Example and Comparative Example of Table 1, Table 2-1 and Table 2-2. be.
• 20 parts by mass of a 2.5 mass% potassium persulfate aqueous solution was dropped over 4 hours.
• the reaction was carried out at 80 ° C. for 2 hours. Then, the mixed solution in the polymerization apparatus was cooled to 25 ° C. Ammonia water was added as a neutralizing agent to adjust the pH to 8.5. Further, 25 parts by mass of Super Ester E-865NT (manufactured by Arakawa Chemical Industry Co., Ltd.) was added as a tackifier, and 2.0 parts by mass of Primal ASE-60 (manufactured by Dow Chemical Co., Ltd.) was added as a thickener.
• Super Ester E-865NT manufactured by Arakawa Chemical Industry Co., Ltd.
• Primal ASE-60 manufactured by Dow Chemical Co., Ltd.
• cross-linking agent (B) or other cross-linking agent) of the type and amount shown in the left column of Table 1, Table 2-1 and Table 2-2 was added.
• a pressure-sensitive adhesive composition was obtained.
• the amount of the cross-linking agent added in the table below means "the amount of the cross-linking agent added to 100 parts by mass of the copolymer (A) (parts by mass)".
• the pressure-sensitive adhesive composition obtained in each Example and Comparative Example was applied to the release surface of a release paper (KP-8D manufactured by Hayashi Convertec Co., Ltd.).
• the applicator used a doctor blade having a coating width of 15 cm.
• the applied pressure-sensitive adhesive composition was dried at 100 ° C. for 3 minutes, the aqueous medium was removed from the pressure-sensitive adhesive composition, and a pressure-sensitive adhesive composition coating layer having a film thickness of 60 ⁇ m was formed on the release surface.
• the pressure-sensitive adhesive composition coating layer on the release surface was transferred to both sides of a non-woven fabric (base material: material: rayon) having a thickness of 40 ⁇ m and a basis weight of 14 g / m 2 cut into A4 size.
• the pressure-sensitive adhesive composition-coated layer transferred onto the non-woven fabric was cured at 40 ° C. for 3 days to form a pressure-sensitive adhesive layer.
• an adhesive tape provided with the base material and the pressure-sensitive adhesive layer formed on the surface of the base material was obtained.
• the release paper was not peeled off even after the transfer in order to prevent foreign matter from adhering to the adhesive layer.
• the ends of the bonded parts did not overlap with the ends of the polypropylene plate. That is, in this state, half of the adhesive tape on one end side in the longitudinal direction is bonded to the polypropylene plate, and half of the other end side is bonded to the release paper.
• the test is a so-called 180 ° peeling test.
• the boundary between the portion where the adhesive tape for evaluation sample was attached to the polypropylene plate and the portion where it was not attached was folded back 180 ° as a folding line.
• One end of the side to which the polypropylene plate of the adhesive tape was not attached was grasped by the chuck on the upper side of the testing machine (Tensilon RTG-1210 (manufactured by A & D Co., Ltd.)).
• the lower chuck grabbed one end of the polypropylene plate that opposes the upper chuck across the folded line.
• the adhesive tape was peeled off from the polypropylene plate at a speed of 200 mm / min, and a graph of peeling length (mm) -peeling force (N) was obtained.
• the average value (N) of the peeling force at the peeling length of 25 to 100 mm is calculated, and this value is used as the initial adhesive force. It was set to (N / 25 mm).
• peeling between the adhesive layer and the base material and cohesive failure of the adhesive layer did not occur during the test.
• the evaluation sample was left in a constant temperature bath at 80 ° C. for 30 minutes. After that, in a constant temperature bath at 80 ° C., using a testing machine (holding force tester (manufactured by Tester Sangyo Co., Ltd.)), grasp the SUS plate side chuck part of the evaluation sample with a chuck, and the SUS plate of the adhesive tape is attached. A weight of 500 g was hung at one end in the longitudinal direction of the unmatched side, and left for 24 hours. Then, the distance (mm) in which the adhesive tape was displaced vertically with respect to the SUS plate was measured.
• a testing machine holding force tester (manufactured by Tester Sangyo Co., Ltd.)
• the adhesive tape produced by using the pressure-sensitive adhesive composition according to the examples exhibits strong adhesive strength not only at room temperature but also at high temperature, and also has high holding power at high temperature. It can be seen that the adhesive layer to have is formed.
• Comparative Examples 1 to 4 and Comparative Examples 8 to 11 produced by using the pressure-sensitive adhesive composition containing no structural unit derived from the monomer (a3) having an alkoxysilyl group.
• the adhesive tape applied to the above at least one of the high temperature adhesive force and the high temperature holding force is not sufficient.
• Comparative Example 2 the blending amount of the cross-linking agent (B) in the pressure-sensitive adhesive composition is increased, but the initial adhesive strength and the high-temperature adhesive strength of the adhesive tape are lowered. Further, in Comparative Example 3 and Comparative Example 4, a polyepoxy compound was used as the cross-linking agent (B), but the high-temperature holding power or high-temperature adhesive power of the adhesive tape was insufficient. From these facts, in the structure of the copolymer (A) which does not contain the structural unit derived from the monomer (a3) having an alkoxysilyl group, the amount of the cross-linking agent (B) contained in the pressure-sensitive adhesive composition is adjusted. It can be seen that the object of the present invention cannot be achieved even if the amount is increased or the type of the functional group of the cross-linking agent (B) is changed.
• the adhesive tape according to Comparative Example 9 in which a large amount of ethylene glycol dimethacrylate is used instead of the monomer (a3) and Comparative Example 11 in which a large amount of divinylbenzene is used has insufficient initial adhesive strength. Met. Further, the adhesive tape according to Comparative Example 8 in which a small amount of ethylene glycol dimethacrylate is used instead of the monomer (a3) and Comparative Example 10 in which a small amount of divinylbenzene is used is significantly inferior in high temperature holding power.
• the adhesive tape according to Comparative Example 5 produced by using the pressure-sensitive adhesive composition containing an excess of the structural unit derived from the monomer (a3) has no initial adhesive strength and high-temperature adhesive strength. It was enough.
• the pressure-sensitive adhesive tape according to Comparative Example 7 produced by using the pressure-sensitive adhesive composition having a low content of the cross-linking agent (B) is significantly inferior in initial adhesive strength and high-temperature adhesive strength.
• an aqueous dispersion type pressure-sensitive adhesive composition capable of forming a pressure-sensitive adhesive layer that exhibits strong adhesive strength not only at room temperature but also at high temperature and also has high holding power at high temperature.
• an adhesive tape that exhibits strong adhesive force not only at room temperature but also at high temperature and also has high holding power at high temperature.

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