WO2012120921A1 - 水分散型粘着剤組成物および粘着シート - Google Patents
水分散型粘着剤組成物および粘着シート Download PDFInfo
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- 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
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- 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]
- C09J7/381—Pressure-sensitive adhesives [PSA] based on macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
- C09J7/385—Acrylic polymers
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
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- 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
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- 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
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- 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
- C09J7/20—Adhesives in the form of films or foils characterised by their carriers
- C09J7/22—Plastics; Metallised plastics
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- 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
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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
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/10—Esters
- C08F220/12—Esters of monohydric alcohols or phenols
- C08F220/16—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms
- C08F220/18—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms with acrylic or methacrylic acids
- C08F220/1808—C8-(meth)acrylate, e.g. isooctyl (meth)acrylate or 2-ethylhexyl (meth)acrylate
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/09—Carboxylic acids; Metal salts thereof; Anhydrides thereof
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L33/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides or nitriles thereof; Compositions of derivatives of such polymers
- C08L33/04—Homopolymers or copolymers of esters
- C08L33/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, which oxygen atoms are present only as part of the carboxyl radical
- C08L33/08—Homopolymers or copolymers of acrylic acid esters
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- 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
- C09J133/08—Homopolymers or copolymers of acrylic acid esters
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- 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
- C09J2301/00—Additional features of adhesives in the form of films or foils
- C09J2301/30—Additional features of adhesives in the form of films or foils characterized by the chemical, physicochemical or physical properties of the adhesive or the carrier
- C09J2301/302—Additional features of adhesives in the form of films or foils characterized by the chemical, physicochemical or physical properties of the adhesive or the carrier the adhesive being pressure-sensitive, i.e. tacky at temperatures inferior to 30°C
Definitions
- the present invention relates to a pressure-sensitive adhesive (also referred to as pressure-sensitive adhesive, hereinafter the same) composition in which an acrylic polymer is dispersed in an aqueous solvent, and a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition.
- a pressure-sensitive adhesive also referred to as pressure-sensitive adhesive, hereinafter the same
- This application claims priority based on Japanese Patent Application No. 2011-052078 filed on Mar. 9, 2011, the entire contents of which are incorporated herein by reference.
- An aqueous pressure-sensitive adhesive composition using an aqueous solvent as a main dispersion medium or solvent is desirable from the viewpoint of reducing the burden on the environment as compared with a solvent-type pressure-sensitive adhesive composition using an organic solvent as a medium. For this reason, also when manufacturing an adhesive sheet, it is desirable to reduce the usage-amount of a solvent-type adhesive composition and to form an adhesive layer mainly with an aqueous adhesive composition.
- Examples of such an aqueous pressure-sensitive adhesive composition include a pressure-sensitive adhesive composition containing an acrylic polymer as a pressure-sensitive adhesive component in an aqueous medium (for example, an emulsion-type pressure-sensitive adhesive composition in which a pressure-sensitive adhesive component is dispersed in an aqueous medium). It has been.
- Patent documents 1 and 2 are mentioned as technical literature about a water dispersion type acrylic adhesive.
- the pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed mainly of an aqueous pressure-sensitive adhesive composition has fine irregularities (mainly in the air bubbles) on the surface like a foam, compared to a pressure-sensitive adhesive sheet using a solvent-type pressure-sensitive adhesive composition.
- the adhesiveness (rough surface adhesiveness) to the adherend (for example, polyurethane foam) having a tendency to occur) tends to be insufficient.
- the water-dispersed pressure-sensitive adhesive composition provided by the present invention comprises an acrylic polymer pA X and an acrylic polymer pA Y in a mass ratio (pA X : pA Y ) 100: 6 to 100: 35.
- the polymer pA X contains an alkyl (meth) acrylate M1 X having 1 to 18 carbon atoms in the alkyl group as a main monomer (main monomer component; monomer occupying 50% by mass or more of all monomer components).
- the polymer pA Y has a weight average molecular weight Mw (referred to a weight average molecular weight based on standard polystyrene based on gel permeation chromatography (GPC)) of 1 ⁇ 10 3 to 50 ⁇ 10 3 .
- the polymer pA Y has a glass transition temperature (Tg) of ⁇ 15 ° C. or lower.
- the polymer pA Y has a copolymer composition including at least an alkyl (meth) acrylate M1 Y having 1 to 18 carbon atoms in the alkyl group and a functional group-containing monomer M2 Y as monomers constituting the polymer. .
- Functionality N of the monomer M2 Y derived contained in the polymer pA Y is per the polymer pA Y 100 g, or less larger and 0.50mol than 0.12 mol.
- C ab the fact that the number of carbon atoms is in the range of a to b may be expressed as “C ab ”.
- an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms may be referred to as “C 1-18 alkyl (meth) acrylate”.
- Such a water-dispersed pressure-sensitive adhesive composition contains two types of polymers pA X and pA Y in the above-mentioned predetermined proportions, and the weight average molecular weight Mw of the polymer pA Y is relatively small, 1 ⁇ 10 3 to 50 ⁇ 10 3.
- the pressure-sensitive adhesive layer formed from the composition is Even when the pressure-sensitive adhesive sheet is attached to a difficult-to-adhere adherend (eg, a foam such as urethane foam) having irregularities on the surface, it has good adhesion (adhesion reliability) to the adherend. ).
- a difficult-to-adhere adherend eg, a foam such as urethane foam
- the said adhesive sheet is equipped with the adhesive layer formed from the aqueous adhesive composition, it is preferable on environmental health. Further, the pressure-sensitive adhesive sheet may have sufficient holding power, terminal peeling prevention property, and repulsion resistance.
- the monomer M2 Y it can be preferably used at least one kind of carboxyl group-containing monomer.
- a PSA composition comprising a polymer pA Y of such a copolymer composition, the pressure-sensitive adhesive sheet showing a better performance can be realized.
- the polymer pA X is tetrahydrofuran (THF) soluble matter having a weight average molecular weight Mw (based on GPC, refers to weight average molecular weight of standard polystyrene.) Is preferably 30 ⁇ 10 4 ⁇ 100 ⁇ 10 4.
- a PSA composition comprising a polymer pA X such Mw, pressure-sensitive adhesive sheet showing a better performance can be realized.
- the polymer pA X has a copolymer composition containing at least 50% by mass (typically 50 to 99% by mass) of 2-ethylhexyl acrylate, and the polymer pA Y has at least 50% of butyl acrylate. It has a copolymer composition containing mass% (typically 50 to 95 mass%). According to such an embodiment, a pressure-sensitive adhesive sheet that exhibits better performance can be realized.
- the pressure-sensitive adhesive composition further comprises 5 to 40 parts by mass of a tackifier with respect to 100 parts by mass of the polymer pA X.
- a pressure-sensitive adhesive sheet exhibiting better pressure-sensitive adhesive properties (for example, a pressure-sensitive adhesive having further improved one or more properties among rough surface adhesion, holding power, terminal peeling prevention and repulsion resistance) Sheet) can be realized.
- a rosin resin is exemplified as a particularly preferable tackifier.
- the pressure-sensitive adhesive formed from the water-dispersed pressure-sensitive adhesive composition has a gel fraction (mass ratio of insoluble ethyl acetate) of 20 to 55%. According to the pressure-sensitive adhesive composition, a pressure-sensitive adhesive sheet with a better performance balance can be realized.
- a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed from any pressure-sensitive adhesive composition disclosed herein.
- Such a pressure-sensitive adhesive sheet has excellent rough surface adhesion, and may have good holding power, terminal peeling prevention property, and repulsion resistance.
- the pressure-sensitive adhesive composition disclosed herein is an aqueous dispersion (typically an aqueous emulsion) containing two kinds of acrylic polymers pA X and pA Y in an aqueous solvent.
- the total amount of these pA X and pA Y preferably occupies 40% by mass or more of the nonvolatile content (adhesive layer forming component, hereinafter also referred to as “adhesive”) contained in the above-mentioned adhesive composition. More preferably, it occupies at least mass%. If the mass ratio of the acrylic polymer in the pressure-sensitive adhesive is too small, the balance of the pressure-sensitive adhesive properties may be easily lost.
- the proportion of the total amount of pA X and pA Y in the pressure-sensitive adhesive may be substantially 100% by mass, but is typically 95% by mass or less, and usually 90% by mass or less (for example, 85% by mass). % Or less). If the mass proportion of the acrylic polymer in the pressure-sensitive adhesive is too large, the balance of the pressure-sensitive adhesive properties may be easily lost.
- the blending ratio (pA X : pA Y ) of the polymer pA X and the polymer pA Y is 100: 6 to 100: 35 (preferably 100: 8 to 100: 35, for example, 100: 10 to 100: 30) on a mass basis. To the extent. If the amount of pA Y with respect to pA X is too small, sufficient rough surface adhesion may not be realized. When the amount of pA Y is too large, edge peel resistance holding power or terminal may become lower.
- polymer pA functional group-containing monomer constituting the Y M2 Y-derived functional groups N is, per the polymer pA Y 100 g, greater than 0.12mol and 0.50mol less (e.g., 0.13 mol to 0.47 mol).
- N is too small, sufficient rough surface adhesion may not be obtained in the pressure-sensitive adhesive sheet having the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition.
- the repulsion resistance may decrease. If N is too large, the terminal peeling prevention property tends to decrease.
- the low-temperature characteristics for example, rough surface adhesiveness in a low-temperature environment, tack, etc.
- N (mol / 100 g) is the total amount of all monomers constituting the polymer pA Y , W T (g), the compounding amount of the functional group-containing monomer M2 Y is W M2Y (g), and the molecular weight of the monomer M2 Y the M W (M2Y) (g / mol), when the number of functional groups contained in one molecule of the monomer M2 Y is n, can be calculated by the following formula (I).
- examples of the functional group contributing to n include a carboxyl group, a hydroxyl group, an amide group, an amino group, a glycidyl group, a maleimide group, an itaconimide group, a succinimide group, a sulfonic acid group, a phosphoric acid group, an isocyanate group, and an alkoxy group.
- a carboxyl group a hydroxyl group, an amide group, an amino group, a glycidyl group, a maleimide group, an itaconimide group, a succinimide group, a sulfonic acid group, a phosphoric acid group, an isocyanate group, and an alkoxy group.
- alkoxysilyl group and the like include a carboxyl group, a hydroxyl group, an amide group, an amino group, a glycidyl group, a maleimide group, an itaconimide group, a succinimide
- the reason why the effect disclosed herein is achieved when the number of functional groups contained in the polymer pA Y is in the desired range is not clear, but the following may be considered, for example. That is, when the elastic modulus of the pressure-sensitive adhesive is lowered, the pressure-sensitive adhesive tends to be easily deformed along fine irregularities on the rough surface. Therefore, lowering the elastic modulus of the pressure-sensitive adhesive can be an effective means for improving rough surface adhesion.
- a technique for reducing the elastic modulus a technique of blending a low molecular weight polymer can be considered. However, the blending of such a low molecular weight polymer can be a factor for reducing the cohesiveness and repulsion resistance of the pressure-sensitive adhesive.
- This polymer pA X is typically based on C 1-18 alkyl (meth) acrylate (monomer M1 X ).
- the ratio (copolymerization ratio) of the C 1-18 alkyl (meth) acrylate (monomer M1 X ) in the total amount of monomers constituting the polymer pA X (hereinafter sometimes referred to as “total monomer component”) is typically For example, it may be 50% by mass or more, for example, 60% by mass or more (typically 60 to 99.9% by mass).
- the content ratio of the monomer M1 X is 70% by mass or more (typically 70 to 99.9% by mass) of the total monomer components, for example, 80% by mass or more (typically 80 to 99.99%). 9% by mass). Further, the content ratio of the monomer M1 X may be 90% by mass or more (typically 90 to 99% by mass) of the total monomer components.
- Such an acrylic polymer can be synthesized by polymerizing (typically emulsion polymerization) a predetermined monomer material. Usually, the monomer composition in the monomer raw material generally corresponds to the copolymer composition (copolymerization ratio) of an acrylic polymer obtained by polymerizing the monomer raw material.
- (meth) acrylate means acrylate and methacrylate comprehensively.
- (meth) acryloyl refers to acryloyl and methacryloyl, and “(meth) acryl” refers to acryl and methacryl generically.
- C 1-18 alkyl (meth) acrylates represented by the following formula (II) can be used.
- CH 2 C (R 1 ) COOR 2 (II) (Wherein R 1 is a hydrogen atom or a methyl group, and R 2 is a C 1-18 alkyl group.)
- C 1-18 alkyl (meth) acrylate examples include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (Meth) acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, n-pentyl (meth) acrylate, isoamyl (meth) acrylate, neopentyl (meth) acrylate, n-hexyl (meth) acrylate, n -Heptyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl (meth)
- 70 mass% or more of the total monomer components constituting the polymer pA X is in the C 2-14 alkyl (meth) acrylate Yes , preferably C 2-10 alkyl (meth) acrylate (eg C 4-10 alkyl acrylate).
- C 2-10 alkyl (meth) acrylate eg C 4-10 alkyl acrylate
- one or both of butyl acrylate (BA) and 2-ethylhexyl acrylate (2EHA) in total is 70% by mass or more (typically 70 to 99% by mass) of the total monomer components, more preferably 80% by mass.
- a monomer composition containing the above typically 80 to 98% by mass
- monomer M1 x consists essentially of one or both of BA and 2EHA.
- the polymer pA X is preferably copolymerized with one or more functional group-containing monomers M2 X.
- the total copolymerization ratio of the functional group-containing monomer M2 X is 12% by mass or less (typically 0.1 to 12% by mass, for example, 0.5 to 12% by mass) of the total monomer components. Usually, it is more preferably 10% by mass or less (typically 0.5 to 10% by mass; for example, 1 to 8% by mass). If the amount of the functional group-containing monomer used is too small, the cohesive force (holding force) may be insufficient. If the amount of the functional group-containing monomer used is too large, the cohesive force becomes too high, and the adhesive properties (for example, adhesive strength) may tend to be reduced.
- the functional group-containing monomer includes at least one radically polymerizable functional group (typically, an ethylenically unsaturated group such as a (meth) acryloyl group or a vinyl group) and another functional group in one molecule.
- radically polymerizable functional group typically, an ethylenically unsaturated group such as a (meth) acryloyl group or a vinyl group
- another functional group in one molecule typically, an ethylenically unsaturated group such as a (meth) acryloyl group or a vinyl group
- Various monomers having them can be preferably used.
- Such functional group-containing monomers include carboxyl group-containing monomers and acid anhydrides thereof.
- Specific examples of the carboxyl group-containing monomer include unsaturated monocarboxylic acids such as acrylic acid (AA), methacrylic acid (MAA), crotonic acid and cinnamic acid; monomethyl itaconate, monobutyl itaconate, 2-acryloxyethylphthalate Unsaturated dicarboxylic acid monoesters such as acids; Unsaturated dicarboxylic acids such as itaconic acid, maleic acid, fumaric acid and citraconic acid; Unsaturated tricarboxylic acids such as 2-methacryloxyethyl trimellitic acid and 2-methacryloxyethyl pyromellitic acid Acid monoesters; carboxyalkyl acrylates such as carboxyethyl acrylate ( ⁇ -carboxyethyl acrylate), carboxypentyl acrylate, etc .; acrylic acid oligomers such as
- hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate; (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-methylol (meth) acrylamide Amide group-containing monomers such as N-methylolpropane (meth) acrylamide and N-vinylcarboxylic acid amide; aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) Acryle Amino group-containing monomers such as 2-hydroxyethyl (me
- functional group-containing monomers include alkoxysilyl group-containing monomers such as silicone (meth) acrylate monomers and silicone vinyl monomers.
- silicone-based (meth) acrylate monomer examples include (meth) acryloxymethyltrimethoxysilane, (meth) acryloxymethyltriethoxysilane, 2- (meth) acryloxyethyltrimethoxysilane, 2- (meth) Acryloxyethyltriethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3- (meth) acryloxypropyltripropoxysilane, 3- (meth) acryloxy (Meth) acryloxyalkyltrialkoxysilanes such as propyltriisopropoxysilane and 3- (meth) acryloxypropyltributoxysilane; (meth) acryloxymethylmethyldimethoxysilane, (meth) acryloxymethylmethyldiethoxysilane 2- (meth) acryloxyethylmethyldimethoxysilane; (
- silicone-based vinyl monomers include vinyltrialkoxysilanes such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinyltriisopropoxysilane, and vinyltributoxysilane; Silane and vinyldialkylalkoxysilane; vinylmethyltrimethoxysilane, vinylmethyltriethoxysilane, ⁇ -vinylethyltrimethoxysilane, ⁇ -vinylethyltriethoxysilane, ⁇ -vinylpropyltrimethoxysilane, ⁇ -vinylpropyltriethoxysilane Vinylalkyltrialkoxysilanes such as ⁇ -vinylpropyltripropoxysilane, ⁇ -vinylpropyltriisopropoxysilane, ⁇ -vinylpropyltributoxysilane; Corresponding to these (vinyl) alkyl dialkoxy silane or (vinyl alkyl
- the functional group-containing monomer M2 X used as a component of the polymer pA X for example, one or more selected from monomer or acid anhydride having a carboxyl group It can be preferably used.
- Substantially all of the functional group-containing monomer M2 X may be a carboxyl group-containing monomer.
- Particularly preferred examples of the carboxyl group-containing monomer include AA and MAA. One of these may be used alone, or AA and MAA may be used in combination at any ratio.
- AA and MAA are copolymerized in the polymer pA X.
- a pressure-sensitive adhesive sheet having more excellent repulsion resistance can be realized.
- the mass ratio of AA to MAA (AA: MAA) can be, for example, in the range of about 1:10 to 10: 1, and is usually about 1: 4 to 4: 1 (eg, 1: 2 to 2: 1). ) Is preferable.
- the amount of copolymerization (the total amount when a plurality of types of carboxyl group-containing monomers are used) is, for example, 12% by mass or less (typically 0. 1 to 12% by mass, for example 0.5 to 12% by mass, is appropriate, and usually 10% by mass or less (typically 0.5 to 10% by mass, for example 0.5 to 5% by mass). Is appropriate).
- the functional group-containing monomer M2 X constituting the polymer pA X includes an alkoxysilyl group-containing monomer.
- an alkoxysilyl group is introduced into the polymer chain, and a crosslinked structure can be formed by a reaction between them.
- Copolymerization of such an alkoxysilyl group-containing monomer can be an advantageous technique for realizing a pressure-sensitive adhesive sheet that can achieve both a high level of rough surface adhesion and cohesion (holding force).
- the copolymerization amount (the total amount when a plurality of types of alkoxysilyl group-containing monomers are used) is, for example, 0.2% by mass or less (typical) Is suitably 0.001 to 0.2% by mass), usually 0.1% by mass or less (typically 0.005 to 0.1% by mass, for example, 0.01 to 0.001%). (05% by mass) is appropriate.
- the functional group-containing monomer M2 X is in the polymer pA X, and one or more selected from monomer or acid anhydride having a carboxyl group, one or two selected from alkoxysilyl group-containing monomer Including at least seeds.
- Substantially all of the functional group-containing monomer M2 X may be a polymer pA X composed of one or both of AA and MAA and a silicone-based (meth) acrylate monomer.
- the polymer pA X may be copolymerized with another monomer (copolymerizable monomer) M3 X copolymerizable with the monomer M1 X as an optional component.
- copolymerizable monomers include alkyl (meth) acrylates having 19 or more carbon atoms; vinyl esters such as vinyl acetate; aromatic unsaturated monomers such as styrene and vinyltoluene; cyclopentyl (meth) acrylate, isobornyl ( (Meth) acrylates of alicyclic alcohols such as (meth) acrylates; olefinic monomers such as ethylene, propylene, isoprene, butadiene and isobutylene; vinyl ether monomers such as vinyl ether; N-vinylpyrrolidone, N- (1-methylvinyl) Pyrrolidone, N-vinyl pyridine, N-vinyl piperid
- a polyfunctional compound having two or more radically polymerizable functional groups typically, ethylenically unsaturated groups such as (meth) acryloyl groups and vinyl groups
- Ionic monomer typically, ethylenically unsaturated groups such as (meth) acryloyl groups and vinyl groups
- polyfunctional monomers include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetraethylene glycol di (meth) (Mono or poly) ethylene glycol di (meth) acrylate such as acrylate; (mono or poly) alkylene glycol di (meth) such as (mono or poly) propylene glycol di (meth) acrylate such as propylene glycol di (meth) acrylate ) Acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane Li (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythri
- Copolymerization proportion of the copolymerizable monomer M3 X in the polymer pA X is a total, 39.5% by weight or less based on the whole monomer components (typically 30 wt% or less, for example 20 wt% or less) and appropriate to Usually, it is preferably 10% by mass or less (for example, 5% by mass or less).
- the copolymer composition may contain substantially no copolymerizable monomer M3 X (for example, the copolymerization ratio of M3 X is less than 0.5% by mass).
- a method by polymerizing such monomers to form a polymer pA X it can be a known or conventional polymerization method can be preferably used among others emulsion polymerization method.
- Aqueous emulsion polymer pA X obtained by such a method can be used as such in the formation of the water-dispersed PSA composition.
- a monomer supply method when emulsion polymerization is performed a batch charging method, a continuous supply (dropping) method, a divided supply (dropping) method, or the like that supplies all monomer raw materials at one time can be appropriately employed.
- the container may be supplied all at once, continuously or divided.
- the polymerization temperature can be appropriately selected according to the type of monomer used, the type of polymerization initiator, and the like, and can be, for example, about 20 ° C. to 100 ° C. (typically 40 ° C. to 80 ° C.).
- the polymerization initiator used in the polymerization can be appropriately selected from known or commonly used polymerization initiators according to the type of polymerization method.
- an azo polymerization initiator can be preferably used in the emulsion polymerization method.
- Specific examples of the azo polymerization initiator include 2,2′-azobisisobutyronitrile (AIBN), 2,2′-azobis (2-methylpropionamidine) disulfate, 2,2′-azobis ( 2-Amidinopropane) dihydrochloride, 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2′-azobis (N, N′-dimethyleneisobutyl) Amidine), 2,2′-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2, 2'-azobis (2,4-
- polymerization initiator examples include persulfates such as potassium persulfate and ammonium persulfate; benzoyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, t-butyl peroxybenzoate, dicumyl Initiates peroxides such as peroxide, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclododecane, hydrogen peroxide Agents; substituted ethane initiators such as phenyl substituted ethane; carbonyl initiators such as aromatic carbonyl compounds; and the like.
- persulfates such as potassium persulfate and ammonium persulfate
- benzoyl peroxide t-butyl hydroperoxide
- di-t-butyl peroxide t-butyl peroxybenzoate
- Still another example of the polymerization initiator includes a redox initiator based on a combination of a peroxide and a reducing agent.
- redox initiators include a combination of a peroxide (hydrogen peroxide solution and the like) and ascorbic acid, a combination of a persulfate and sodium bisulfite, and the like.
- Such polymerization initiators can be used alone or in combination of two or more.
- the amount of the polymerization initiator is, for example, from the range of about 0.005 to 1 parts by weight with respect to all monomer components 100 parts by mass (typically 0.01 to 1 part by weight) used for the synthesis of pA X You can choose.
- chain transfer agents which can also be grasped as molecular weight regulators or polymerization degree regulators
- a chain transfer agent may be one or more selected from mercaptans such as n-lauryl mercaptan, tert-lauryl mercaptan, glycidyl mercaptan, 2-mercaptoethanol and the like. Of these, use of n-lauryl mercaptan is preferred.
- the amount of the chain transfer agent based on the total monomer components 100 parts by weight used in the synthesis of pA X, can be, for example, about 0.001 to 0.5 parts by mass. The amount used may be about 0.02 to 0.05 parts by mass.
- the polymerization reaction in emulsion form which acrylic polymer pA X is dispersed in water is obtained.
- the aqueous emulsion of the polymer pA X in the art disclosed herein can be preferably used which has been subjected to appropriate post-processing to the polymerization reaction mixture or the reaction mixture.
- emulsion polymerization polymerization method other than the method e.g., solution polymerization, photopolymerization, bulk polymerization, etc.
- the post-treatment can include, for example, an operation of adjusting the pH of the emulsion liquid phase to about 7 to 9 (for example, about 7 to 8) with a base (ammonia water or the like) or an acid.
- an emulsifier can be used if necessary.
- the emulsifier any of anionic, nonionic, and cationic types can be used. Usually, the use of an anionic or nonionic emulsifier is preferred.
- Such emulsifiers are, for example, or when the monomer material by emulsion polymerization to synthesize the polymer pA X, an acrylic polymer pA X obtained in other ways can be preferably used in such case to be dispersed in water .
- anionic emulsifiers include sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzene sulfonate, sodium polyoxyethylene alkyl ether sulfate, ammonium polyoxyethylene alkyl phenyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate and the like.
- nonionic emulsifiers include polyoxyethylene alkyl ether and polyoxyethylene alkyl phenyl ether.
- a radical polymerizable emulsifier (reactive emulsifier) having a structure in which a radical polymerizable group (propenyl group or the like) is introduced into these anionic or nonionic emulsifiers may be used. Or you may use only the emulsifier which does not have this radically polymerizable group.
- Such emulsifiers can be used alone or in combination of two or more.
- the amount of the emulsifier used is not particularly limited as long as it is an amount used to prepare the acrylic polymer in the form of an emulsion. Usually, it is appropriate to select from a range of, for example, about 0.2 to 10 parts by mass (preferably 0.5 to 5 parts by mass) per 100 parts by mass of the acrylic polymer.
- Polymer pA X has a weight average molecular weight Mw of the THF-soluble matter is preferably in the range about of 30 ⁇ 10 4 ⁇ 100 ⁇ 10 4. If Mw is too small, the cohesive force of the resulting pressure-sensitive adhesive layer may tend to decrease. In addition, a structure in which a low molecular weight polymer pA Y forms a domain in a matrix of the polymer pA X is difficult to be realized, and rough surface adhesion may be deteriorated.
- the weight average molecular weight Mw of the polymer pA X shall be adopted measured values according to the following methods. ⁇ Method of measuring the Mw of the polymer pA X> A sample of the acrylic polymer pA X to be measured is immersed in THF at 23 ° C. for 7 days to elute the THF soluble component. The THF-insoluble matter is removed by filtration, and the resulting filtrate is concentrated or diluted with THF as necessary to prepare a THF solution containing the THF-soluble matter at a concentration of about 0.1 to 0.3% by mass. .
- a weight average molecular weight Mw based on a standard polystyrene is obtained from a filtrate obtained by filtering this THF solution with a filter having an average pore diameter of 0.45 ⁇ m by a gel permeation chromatography (GPC) apparatus.
- GPC gel permeation chromatography
- a model “HLC-8320GPC” column: TSKgel GMH-H (S)
- S TSKgel GMH-H
- the sample of the acrylic polymer pA X, a polymer pA X obtained by emulsion polymerization drying may be used those obtained by.
- This polymer pA Y is an acrylic polymer having a relatively low molecular weight (specifically, a weight average molecular weight Mw in the range of about 1 ⁇ 10 3 to 50 ⁇ 10 3 ), and is a C 1-18 alkyl ( It has a copolymer composition containing (meth) acrylate M1 Y and functional group-containing monomer M2 Y.
- the “functional group-containing monomer M2 Y ” is used to include not only monomers but also oligomers (typically dimers (dimers) and trimers (trimers)).
- the Mw of the polymer pA Y is preferably about 1.5 ⁇ 10 3 to 9 ⁇ 10 3 , more preferably about 2 ⁇ 10 3 to 8 ⁇ 10 3 , and further preferably about 2 ⁇ 10 3 to 5 ⁇ 10 3 . is there. If the Mw of the polymer pA Y is too small, the cohesive force of the resulting pressure-sensitive adhesive layer is lowered. If Mw is too large, the rough surface adhesion may not be sufficiently improved.
- the weight average molecular weight Mw of the acrylic polymer pA Y a value measured according to the following method is adopted.
- ⁇ Method for Measuring Mw of Polymer pA Y To prepare a measurement solution containing a concentration of about 0.1 to 0.3% by mass (e.g., 0.2 wt%) in the measurement target serving acrylic polymer pA Y 10mM-LiBr + 10mM phosphoric acid / DMF (diluent) .
- a weight average molecular weight Mw based on a standard polystyrene is determined by a GPC apparatus for a filtrate obtained by filtering the THF solution with a filter having an average pore diameter of 0.45 ⁇ m.
- a model “HLC-8120GPC” manufactured by Tosoh Corporation or an apparatus having an accuracy equivalent to this can be used.
- Mw of the polymer pA Y can be measured by applying the Mw measurement conditions described in the examples described later.
- a polymerization reaction liquid typically, a solution containing the polymer pA Y at a concentration of 20% by mass or more
- What was diluted and prepared can be used.
- the standard polystyrene is used for the soluble matter extracted by immersing the polymer pA Y in THF at 23 ° C. for 7 days.
- the reference weight average molecular weight Mw shall be obtained.
- the polymer pA Y in the technology disclosed herein has a Tg of ⁇ 15 ° C. or less (typically ⁇ 70 ° C. to ⁇ 15 ° C., preferably ⁇ 60 ° C. to ⁇ 15 ° C., for example, ⁇ 50 ° C. to ⁇ 20 ° C. About) can be preferably employed. If the Tg of the polymer pA Y is too high, the effect of improving the rough surface adhesive strength is likely to be inadequate.
- Tg is determined from the Fox equation based on the Tg of the homopolymer of each monomer constituting the polymer pA Y and the mass fraction of the monomer (copolymerization ratio based on mass). Value.
- Tg of the homopolymer the value described in known materials is adopted. In the technique disclosed here, the following values are specifically used as the Tg of the homopolymer.
- Tg of the homopolymer for those other than those described above.
- PAM200 (trade name) 0 ° C M5600 (trade name) 12 ° C M5300 (trade name) -35 °C
- the value obtained by the following method is adopted as the Tg of the homopolymer. That is, a target monomer is solution polymerized to synthesize a homopolymer having a weight average molecular weight of 5 ⁇ 10 4 to 10 ⁇ 10 4 , and the obtained homopolymer solution is cast and dried on a release liner to prepare a test sample. To do. For this test sample, the temperature was changed from ⁇ 80 ° C. to 280 ° C. at a rate of temperature increase of 10 ° C./min using a differential scanning calorimeter (DSC), model “DSC 6220” manufactured by SII Nano Technology Co., Ltd. Differential scanning calorimetry is performed, and the initial endothermic start temperature is defined as Tg of the homopolymer.
- DSC differential scanning calorimeter
- the proportion of M1 Y in the total monomer components constituting the polymer pA Y can be, for example, 30% by mass or more, and is usually appropriately 50% by mass or more.
- the ratio of M1 Y is about 60 to 95% by mass (more preferably about 70 to 95% by mass, for example, about 70 to 92% by mass). If the amount of M1 Y is too small, the balance of adhesive properties may be easily lost.
- the C 1-18 alkyl (meth) acrylate as a monomer M1 Y exemplified C 1-18 alkyl as a monomer M1 X that may be used in the preparation of a polymer pA X (meth) acrylate (preferably C 2-14 alkyl ( Monomers similar to (meth) acrylates such as C 2-10 alkyl (meth) acrylates can be used.
- Such C 1-18 alkyl (meth) acrylates can be used alone or in combination of two or more.
- the proportion of M2 Y in the total monomer components constituting the polymer pA Y is disclosed here as the number of functional groups derived from M2 Y (typically the number of carboxyl groups) N contained per 100 g of the polymer pA Y. It can be appropriately selected so as to be within a preferable numerical range.
- the ratio of M2 Y can typically be about 5 to 40% by mass of the total monomer components (preferably about 7 to 37% by mass, for example about 7 to 35% by mass). More preferably, the content is 5 to 30% by mass (typically 8 to 30% by mass).
- the amount of M2 Y is too small, in the pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed from the water-dispersed pressure-sensitive adhesive composition containing the polymer pA Y , rough surface adhesion, repulsion resistance, holding power, terminal peeling At least one of the preventive properties may be insufficient. If the amount of M2 Y is too large, sufficient rough surface adhesion may not be realized.
- 70 to 95% by mass (for example, 70 to 92% by mass) of the total monomer components constituting the polymer pA Y is C 2-14 alkyl (meth) acrylate, preferably C 2-10 alkyl (meth) acrylate (eg C 4-10 alkyl acrylate).
- monomer M1 Y consists essentially of one or both of BA and 2EHA. The use ratio of BA and 2EHA is not particularly limited.
- the same functional group-containing monomer as exemplified as the monomer M2 X that can be used for the preparation of the polymer pA X can be used.
- Such functional group-containing monomers can be used alone or in combination of two or more.
- the monomer M2 Y comprises at least a carboxyl group-containing monomer.
- the carboxyl group-containing monomers exemplified as the monomer M2 X which can be used in the preparation of the polymer pA X as a monomer M2 Y, preferably acrylic acid, methacrylic acid and acrylic acid oligomers (typically dimers), such as Can be used.
- preferred examples of the carboxyl group-containing monomer include acrylic acid and acrylic acid dimer (for example, trade name “Aronix M5600” manufactured by Toagosei Co., Ltd. or its equivalent). These carboxyl group-containing unsaturated compounds can be used alone or in combination of two or more.
- substantially all of the monomer M2 Y is a carboxyl group-containing monomer.
- a polymer pA Y in which the monomer M2 Y includes one or both of acrylic acid and an acrylic acid oligomer (typically acrylic acid dimer) can be preferably employed.
- the number N of functional groups derived from the carboxyl group-containing monomer M2 Y contained in the polymer pA Y is greater than 0.12 mol and less than or equal to 0.50 mol per 100 g of the polymer pA Y (typically 0.13 mol to 0 .47 mol), and may be 0.15 mol to 0.40 mol (eg, 0.16 mol to 0.37 mol).
- N of the functional groups derived from the carboxyl group-containing monomer M2 Y is too small, it may be difficult to obtain a sufficient rough surface adhesion improving effect, or the repulsion resistance may be insufficient.
- N is too large, the terminal peeling prevention property tends to be lowered, and the low temperature characteristics may be easily lowered. Further, the number calorific value during polymerization, the burden of temperature control for the production of polymers pA Y having a Mw of preferred ranges described above may sometimes increase.
- the polymer pA Y in addition to the aforementioned monomers, as an optional component, a monomer M1 X and other copolymerizable monomer (copolymerizable monomer) M3 Y may be copolymerized.
- a copolymerizable monomer a copolymerizable monomer similar to that exemplified as the monomer M3 X that can be used for the preparation of the polymer pA X can be used.
- Such functional group-containing monomers can be used alone or in combination of two or more.
- Copolymerization proportion of the copolymerizable monomer M3 Y in the polymer pA Y is the sum, 35 wt% or less based on the whole monomer components (typically 30 wt% or less, for example 20 wt% or less) suitable to be Usually, it is preferably 10% by mass or less (for example, 5% by mass or less).
- the copolymer composition may contain substantially no copolymerizable monomer M3 Y (for example, the copolymerization ratio of M3 Y is less than 0.5% by mass).
- Polymerization of these monomers typically polymerization under an inert gas atmosphere such as nitrogen gas
- Polymerization of these monomers to form the polymer pA Y includes known or conventional polymerization methods (emulsion polymerization, bulk polymerization (bulk polymerization)). , Photopolymerization, solution polymerization, etc.) can be used.
- emulsion polymerization As a preferable polymerization method from the viewpoint of reducing environmental load, emulsion polymerization and bulk polymerization may be mentioned.
- the polymer pA Y is obtained in the form of an emulsion, and this form of pA Y is preferred because it can be easily mixed with an aqueous emulsion of the polymer pA X.
- the solution polymerization is advantageous in that the molecular weight of the polymer pA Y accurately and easily adjusted.
- the aforementioned batch charging method, continuous supply (dropping) method, divided supply (dropping) method, etc. can be appropriately employed.
- a part or all (typically all) of the monomer may be dissolved or dispersed in a solvent in advance, and the solution may be supplied into the reaction vessel all at once, continuously or dividedly.
- the polymerization temperature can be appropriately selected according to the type of monomer used, the type of polymerization initiator, and the like, and can be, for example, about 20 ° C. to 100 ° C. (typically 40 ° C. to 80 ° C.).
- the polymerization time (reaction time) can be, for example, 1 to 12 hours (typically 4 to 12 hours).
- the polymerization initiator a known or commonly used polymerization initiator can be used without particular limitation.
- the above-described polymerization initiator can be appropriately selected and used.
- a polymerization initiator can be used individually by 1 type or in combination of 2 or more types.
- the amount of the polymerization initiator can be appropriately adjusted so that the polymer pA Y having a desired Mw can be obtained.
- it can be selected from a range of about 0.01 to 10 parts by mass (typically 0.05 to 5 parts by mass) with respect to 100 parts by mass of all monomer components used for the synthesis of the polymer pA Y.
- chain transfer agents which can also be grasped as molecular weight regulators or polymerization degree regulators
- a chain transfer agent may be one or more selected from mercaptans such as n-lauryl mercaptan, tert-lauryl mercaptan, glycidyl mercaptan, 2-mercaptoethanol and the like. Of these, tert-lauryl mercaptan is preferably used.
- the amount of the chain transfer agent used can be appropriately adjusted so as to obtain a polymer pA Y having a desired Mw.
- the amount of the chain transfer agent used relative to 100 parts by mass of all monomer components used in the synthesis of pA Y can be, for example, about 0.1 to 30 parts by mass.
- the amount used may be about 1 to 30 parts by mass, or about 5 to 30 parts by mass (for example, 10 to 30 parts by mass).
- a suitable organic solvent in the reaction vessel e.g., A small amount of toluene, xylene, benzene, etc.
- This approach may be preferably employed in the case of the bulk polymerization the synthesis of the acrylic polymer pA Y.
- an aqueous emulsion comprising a pA X and pA Y.
- a polymer pA Y in a form substantially free of volatile components is obtained by bulk polymerization or photopolymerization, etc.
- (1) The polymer pA Y is directly added to an aqueous emulsion of pA X and stirred and mixed.
- the pA Y when the polymer pA Y is synthesized by solution polymerization or when a small amount of an organic solvent is added for the purpose of facilitating the removal of the contents after bulk polymerization as described above, the pA Y in a form containing an organic solvent.
- the copolymerization ratio of the C 2-18 alkyl (meth) acrylate in the polymer pA X is 60 to 99.5 wt%, C 2-18 alkyl (meth in polymer pA Y )
- the copolymerization ratio of acrylate is 60 to 95% by mass.
- the solubility parameter calculated from the composition of the C 2-18 alkyl (meth) acrylate composing the polymer pA X is SP X, and calculated from the composition of the C 2-18 alkyl (meth) acrylate composing the polymer pA Y.
- the rough surface adhesion and other characteristics can be achieved at a higher level.
- E v is the evaporation energy
- v is the molar volume
- ⁇ e i is the evaporation energy of each atom or atomic group
- ⁇ v i is the molar volume of each atom or atomic group
- the SP value of each C 2-18 alkyl (meth) acrylate homopolymer includes the C 2-18 alkyl ( meth) mole fraction of acrylate (i.e., the C 2-18 alkyl (meth) the number of moles of acrylate multiplied by percentage) to the total number of moles of all C 2-18 alkyl (meth) acrylate, the total those values
- the SP value for the C 2-18 alkyl (meth) acrylate constituting the acrylic polymer can be calculated.
- the pressure-sensitive adhesive layer formed from the water-dispersed pressure-sensitive adhesive composition having such ⁇ SP characteristics is low in the matrix of the polymer pA X having a relatively high molecular weight because the polymer pA X and the polymer pA Y are poorly compatible with each other. It is easy to take a structure in which the molecular weight polymer pA Y forms a domain. Therefore, tends polymer pA Y of low molecular weight is unevenly distributed on the surface (adhesive surface) of the adhesive sheet.
- ⁇ SP is 0.30 (cal / cm 3 ) 1/2 or more (about 0.6 (J / cm 3 ) 1/2 or more).
- the upper limit of ⁇ SP is not particularly limited, but is usually 0.70 (cal / cm 3 ) 1/2 or less (about 1.4 (J / cm 3 ) 1/2 or less), typically 0 .60 (cal / cm 3 ) 1/2 or less (about 1.2 (J / cm 3 ) 1/2 or less).
- ⁇ SP is 0.50 (cal / cm 3 ) 1/2 or less (about 1.0 (J / cm 3 ) 1/2 or less).
- either SP X or SP Y may be larger, but for example, an aspect where SP X ⁇ SP Y can be preferably employed.
- the values of the evaporation energy, molar volume, etc. of each atom or atomic group used for calculating the SP value are described in Journal of the Adhesion Society of Japan, Vol. 22, no. 10 (1986), p566, etc. may be used.
- the SP values of homopolymers of various alkyl (meth) acrylates are, for example, 9.77 (cal / cm 3 ) 1/2 for butyl acrylate homopolymer and 9.22 (cal / cm for 2-ethylhexyl acrylate homopolymer).
- the polymer pA X has a SP X in the range of 9.1 to 10.0 (typically 9.2 to 9.8, for example, 9.3 to 9.7) (cal / cm 3 ) 1/2 . Some can be preferably employed.
- SP Y is in the range of 9.1 to 10.0 (typically 9.2 to 9.8) (cal / cm 3 ) 1/2 and ⁇ SP is 0.25. What is (cal / cm ⁇ 3 >) ⁇ 1/2 > or more can be employ
- SP X is in the range of 9.2 to 9.5 (preferably 9.3 to 9.5) (cal / cm 3 ) 1/2
- SP Y is 9.5 to 9.8 (typically 9.6 to 9.8) (cal / cm 3 ) 1/2
- ⁇ SP is 0.25 (cal / cm 3 ) 1/2 It is preferable to determine the composition of the monomer M1 X and the monomer M1 Y so as to be the above.
- the polymer pA X has a copolymer composition containing at least 50% by mass (typically 50 to 99% by mass) of 2-ethylhexyl acrylate, and the polymer pA Y has at least 50% of butyl acrylate. It has a copolymer composition containing mass% (typically 50 to 95 mass%). According to this aspect, it is possible to easily realize the polymers pA X and pA Y having SP Y -SP X of 0.25 (cal / cm 3 ) 1/2 or more.
- a general crosslinking agent such as a carbodiimide crosslinking agent, a hydrazine crosslinking agent, an epoxy crosslinking agent, an isocyanate crosslinking agent, an oxazoline crosslinking agent, an aziridine crosslinking agent, What added the crosslinking agent selected from a metal chelate type crosslinking agent, a silane coupling agent, etc. (after-addition, ie, the thing to which this crosslinking agent was added after the synthesis
- Such crosslinking agents may be used alone or in combination of two or more.
- the adhesive composition in which such post-addition of a crosslinking agent is not substantially performed may be sufficient.
- a post-added crosslinking agent is substantially used.
- the structure which does not carry out can be employ
- These crosslinking agents can be added, for example, at a ratio of 0.01 to 10 parts by mass with respect to 100 parts by mass of the total amount of the acrylic polymers pA X and pA Y , for example.
- the water-dispersed pressure-sensitive adhesive composition disclosed herein may further contain a tackifier.
- a tackifier it is possible to use one or two or more kinds selected from various tackifier resins such as rosin resin, rosin derivative resin, petroleum resin, terpene resin, phenol resin, and ketone resin. It can. Of these, the use of a rosin resin is preferred.
- Commercially available tackifiers include trade names “Superester E-865” (softening point 160 ° C.), “Superester E-865NT” (softening point 160 ° C.), “Superester” manufactured by Arakawa Chemical Industries, Ltd.
- a tackifier having a softening point of 140 ° C. or higher is preferable.
- a tackifier with a softening point of about 160 ° C or higher more excellent properties (for example, cohesiveness and other properties (rough surface adhesion, terminal peeling prevention, etc.) can be achieved at a higher level.
- An adhesive layer can be formed.
- the addition mode of the tackifier is not particularly limited. Typically, the tackifier is added in the form of an aqueous dispersion (tackifier emulsion) dispersed in water.
- the amount of tackifier used can be, for example, 5 parts by mass or more, and usually 10 parts by mass or more (for example, 15 parts by mass or more) with respect to 100 parts by mass of the acrylic polymer pA X. An effect is obtained. From the viewpoint of balance with other adhesive properties (for example, one or both of repulsion resistance and holding power), the amount of the tackifier used is suitably 40 parts by mass or less, usually 30 parts by mass. The following (for example, 25 parts by mass or less) is preferable. If the amount of the tackifier is too small, at least one of the repulsion resistance, holding power, and terminal peeling prevention property of the obtained pressure-sensitive adhesive sheet may be lowered. When there is too much quantity of a tackifier, rough surface adhesiveness may fall.
- the pressure-sensitive adhesive composition may further contain a polymer component other than the polymers pA X and pA Y.
- polymer components include polymers having rubber or elastomer properties. Specific examples include ethylene-vinyl acetate copolymer, acrylic rubber, natural rubber (NR), isoprene rubber (IR), styrene butadiene rubber (SBR), chloroprene rubber (CR), butyl rubber (IIR), ethylene propylene rubber ( EPM, EPDM), polyisobutylene, styrene-ethylene-butylene-styrene copolymer (SEBS), acrylonitrile-butadiene copolymer (NBR), styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene A block copolymer (SIS), polyvinyl alkyl ether (for example, polyvinyl isobutyl
- polymer components can be used singly or in combination of two or more.
- Such a polymer component can be mixed with other components, for example, in the form of an emulsion in which the polymer component is dispersed in water.
- the content (mixing ratio) of the polymer component is usually 50 parts by mass or less (for example, 5 to 50 parts by mass) with respect to 100 parts by mass of the acrylic polymer, based on the nonvolatile content (solid content). Is appropriate.
- the blending ratio of the polymer component may be 5 parts by mass or less, and may be a pressure-sensitive adhesive composition having a composition that does not substantially contain the polymer component.
- the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition disclosed herein has a gel fraction of the pressure-sensitive adhesive of, for example, about 20 to 55% (for example, 25% to less than 40%, typically 30% to 40%). Less than%).
- the conditions such as the conditions for forming the pressure-sensitive adhesive layer (drying conditions, light irradiation conditions, etc.), the type and amount of the crosslinking agent, and the like may be appropriately set.
- the “gel fraction of the pressure-sensitive adhesive” refers to a value measured by the following method. The gel fraction can be grasped as a mass ratio of an ethyl acetate insoluble component in the pressure-sensitive adhesive.
- a pressure-sensitive adhesive sample (mass Wg 1 ) is wrapped in a purse-like shape with a porous polytetrafluoroethylene membrane (mass Wg 2 ) having an average pore diameter of 0.2 ⁇ m, and the mouth is bound with octopus yarn (mass Wg 3 ).
- This packet is soaked in 50 mL of ethyl acetate and kept at room temperature (typically 23 ° C.) for 7 days to elute only the sol component in the pressure-sensitive adhesive layer outside the membrane, and then the packet is taken out to the outer surface.
- the attached ethyl acetate is wiped off, the package is dried at 130 ° C.
- Gel fraction F G of the adhesive is determined by substituting each value into the following formula.
- Gel fraction F G (%) [(Wg 4 ⁇ Wg 2 ⁇ Wg 3 ) / Wg 1 ] ⁇ 100
- porous polytetrafluoroethylene (PTFE) membrane As the porous polytetrafluoroethylene (PTFE) membrane, a trade name “Nitoflon (registered trademark) NTF1122” available from Nitto Denko Corporation (average pore diameter 0.2 ⁇ m, porosity 75%, thickness 85 ⁇ m) Or it is desirable to use the equivalent.
- Nitto Denko Corporation a trade name “Nitoflon (registered trademark) NTF1122” available from Nitto Denko Corporation (average pore diameter 0.2 ⁇ m, porosity 75%, thickness 85 ⁇ m) Or it is desirable to use the equivalent.
- the pressure-sensitive adhesive composition may contain an acid or a base (such as aqueous ammonia) used for the purpose of adjusting pH, if necessary.
- Other optional components that can be contained in the composition include aqueous pressure-sensitive adhesives such as viscosity modifiers, leveling agents, plasticizers, fillers, colorants such as pigments and dyes, stabilizers, preservatives, and anti-aging agents.
- aqueous pressure-sensitive adhesives such as viscosity modifiers, leveling agents, plasticizers, fillers, colorants such as pigments and dyes, stabilizers, preservatives, and anti-aging agents.
- various additives that are common in the field of compositions are exemplified. About such various additives, conventionally well-known things can be used by a conventional method, and since it does not characterize this invention in particular, detailed description is abbreviate
- the pressure-sensitive adhesive sheet provided by the present invention includes a pressure-sensitive adhesive layer formed from any pressure-sensitive adhesive composition disclosed herein. It may be a pressure-sensitive adhesive sheet with a base material having such a pressure-sensitive adhesive layer on one side or both sides of a base material (support), and the pressure-sensitive adhesive layer may be grasped as a release liner (a base material having a release surface). It may be a substrate-less pressure-sensitive adhesive sheet such as a form held in ().
- the concept of the pressure-sensitive adhesive sheet herein may include what are called pressure-sensitive adhesive tapes, pressure-sensitive adhesive labels, pressure-sensitive adhesive films and the like.
- the pressure-sensitive adhesive layer is typically formed continuously, but is not limited to such a form.
- the pressure-sensitive adhesive layer is formed in a regular or random pattern such as a dot shape or a stripe shape. It may be.
- the pressure-sensitive adhesive sheet provided by the present invention may be in the form of a roll or a single sheet. Or the adhesive sheet of the form processed into various shapes may be sufficient.
- FIG. 1 is a structural example of the adhesive sheet with a base material of a double-sided adhesive type.
- the pressure-sensitive adhesive sheet 1 shown in FIG. 1 is provided with pressure-sensitive adhesive layers 21 and 22 on each surface (both non-peelable) of the base material 10, and these pressure-sensitive adhesive layers have at least the pressure-sensitive adhesive layer side as a release surface. It has the structure protected by the release liners 31 and 32 respectively.
- the pressure-sensitive adhesive sheet 2 shown in FIG. 2 is provided with pressure-sensitive adhesive layers 21 and 22 on each surface (both non-peelable) of the base material 10, respectively.
- This type of pressure-sensitive adhesive sheet 2 has a configuration in which the pressure-sensitive adhesive layer 22 is also protected by the release liner 31 by winding the pressure-sensitive adhesive sheet and bringing the other pressure-sensitive adhesive layer 22 into contact with the back surface of the release liner 31. be able to.
- the pressure-sensitive adhesive sheet 3 shown in FIG. 3 has a configuration in which both surfaces 21A and 21B of a base material-less pressure-sensitive adhesive layer 21 are protected by release liners 31 and 32 having at least a pressure-sensitive adhesive layer side, respectively.
- the pressure-sensitive adhesive sheet 4 shown in FIG. 4 has a structure in which one surface (adhesive surface) 21A of the base material-less pressure-sensitive adhesive layer 21 is protected by a release liner 31 whose both surfaces are release surfaces. When wound, the other surface (adhesive surface) 21B of the pressure-sensitive adhesive layer 21 is brought into contact with the back surface of the release liner 31 so that the other surface 21B is also protected by the release liner 31.
- the pressure-sensitive adhesive sheet 5 shown in FIG. 5 is provided with a pressure-sensitive adhesive layer 21 on one surface 10A (non-peelable) of the substrate 10, and at least the surface (pressure-sensitive adhesive surface) 21A of the pressure-sensitive adhesive layer 21 is peeled off at the pressure-sensitive adhesive layer side. It has the structure protected with the release liner 31 used as the surface.
- the pressure-sensitive adhesive sheet 6 shown in FIG. 6 has a configuration in which a pressure-sensitive adhesive layer 21 is provided on one surface 10 ⁇ / b> A (non-peelable) of the substrate 10.
- the other surface 10B of the substrate 10 is a release surface. When the adhesive sheet 6 is wound, the adhesive layer 21 comes into contact with the other surface 10B, and the surface (adhesive surface) 21B of the adhesive layer is the substrate. It is protected by the other surface 10B.
- various resin films polyethylene (PE), polypropylene (PP), ethylene / propylene copolymer
- Polyolefin films such as coalescence; Polyester films such as polyethylene terephthalate (PET); Polyvinyl chloride, etc.), Papers (craft paper, Japanese paper, fine paper, etc.), woven fabrics such as single or mixed spinning of various fibrous materials, Foam sheets (foamed polyurethane sheets, etc.) made of foams such as non-woven fabrics (cotton cloth, soft cloth, PE non-woven fabric, vinylon non-woven fabric, etc.), rubber sheets (natural rubber sheet, etc.), and expanded polychloroprene rubber.
- the substrate may have a single layer form or may have a laminated form.
- the thickness of the substrate can be appropriately selected depending on the purpose, but is generally 10 ⁇ m to 500 ⁇ m (preferably 10 ⁇ m to 200 ⁇ m). From the viewpoint of repulsion resistance, it is advantageous to use a substrate having a thickness of 10 ⁇ m to 50 ⁇ m.
- nonwoven fabric refers to a non-woven fabric for pressure-sensitive adhesive sheets mainly used in the field of pressure-sensitive adhesive tapes and other pressure-sensitive adhesive sheets, and is typically produced using a general paper machine. Non-woven fabric (sometimes called “paper”).
- the resin films may be any of an unstretched film, a uniaxially stretched film, and a biaxially stretched film.
- the surface of the substrate on which the pressure-sensitive adhesive layer is provided may be subjected to surface treatment such as application of a primer, corona discharge treatment, plasma treatment or the like.
- the thickness of the pressure-sensitive adhesive layer can be, for example, about 5 ⁇ m to 500 ⁇ m (preferably 5 ⁇ m to 200 ⁇ m).
- the thickness of an adhesive layer here means the thickness of the adhesive layer per one side in the case of the double-sided adhesive sheet in which the adhesive layer was provided in both surfaces of the base material.
- the thickness of the pressure-sensitive adhesive layer attached to the foam is 30 ⁇ m or more (preferably in order to obtain good rough surface adhesion to the foam. Is preferably 40 ⁇ m or more.
- the thickness of the pressure-sensitive adhesive layer is preferably 100 ⁇ m or less from the viewpoint of balance with other pressure-sensitive adhesive properties, productivity of the pressure-sensitive adhesive sheet, and the like.
- the pressure-sensitive adhesive sheet has at least one of properties (A), (B), (C) and (D) described below (more preferably, two of these). Meet one or more characteristics.
- the thickness of the pressure-sensitive adhesive layer is preferably about 40 ⁇ m to 100 ⁇ m (typically about 50 ⁇ m to 90 ⁇ m, for example, about 80 ⁇ m).
- a double-sided pressure-sensitive adhesive sheet in which the above-mentioned thickness of the pressure-sensitive adhesive layer is provided on both sides of the nonwoven fabric a base-less double-sided pressure-sensitive adhesive sheet composed of the above-mentioned thickness of the pressure-sensitive adhesive layer, and single-sided pressure-sensitive adhesive having the above-mentioned thickness of the pressure-sensitive adhesive layer It can be a sheet, etc.
- release liner a known or commonly used release liner can be appropriately selected and used.
- a release liner from various resin films, papers, cloths, rubber sheets, foam sheets, metal foils, and composites thereof (for example, sheets having a laminated structure in which olefin resin is laminated on both sides of paper)
- a release liner having a configuration in which a release treatment is performed on the surface of the base material as necessary can be suitably used.
- the pressure-sensitive adhesive sheet satisfies the following property (A). That is, at 23 ° C., the pressure-sensitive adhesive sheet is applied to a flexible urethane foam having a thickness of 10 mm in a free state (in which no external force is applied), and the urethane foam is formed to a thickness of 2 mm (that is, 20% of the above-mentioned free state as a reference).
- A the pressure-sensitive adhesive force (compressed to the thickness) is pressed and the 180 ° peel adhesive strength (rough surface adhesive strength as an index of rough surface adhesion) is measured 30 minutes after the pressure bonding, the adhesive strength is 3.
- ECS foam a polyether urethane foam having a density of 22 ⁇ 2 kg ⁇ m 3 and hardness (according to D method defined in JIS K6400-2 (2004)) of 107.9 ⁇ 22.6N.
- the upper limit of the rough surface adhesive force is not particularly limited, but is usually 10 N / 20 mm or less in consideration of the strength of the ECS foam itself.
- the rough surface adhesive force can be measured, for example, as follows. First, a pressure-sensitive adhesive sheet to be subjected to performance evaluation is cut into a strip shape (typically a strip shape) having a predetermined width to produce a sample piece. At this time, when the pressure-sensitive adhesive sheet is in the form of a baseless or double-sided pressure-sensitive adhesive sheet with a base material, an appropriate backing material is previously applied to one pressure-sensitive adhesive surface in order to improve the handling property and reinforce the pressure-sensitive adhesive sheet. It is preferable to attach it. For example, a polyethylene terephthalate (PET) film having a thickness of about 20 ⁇ m to 30 ⁇ m (typically 25 ⁇ m) can be preferably used as the backing material.
- PET polyethylene terephthalate
- the width of the sample piece is usually preferably 20 mm. However, even when using a sample piece having a different width Xmm, the measurement result obtained using the sample piece is 20 / By multiplying by X, the measurement result can be converted into an adhesive force per 20 mm width. In the following description, a sample piece having a width of 20 mm is used. What is necessary is just to set the length of a sample piece so that sufficient sticking length with respect to a to-be-adhered body can be ensured. Usually, the affixing length (adhesive surface length) is suitably 20 mm or more, and more preferably 50 mm or more.
- the sample piece is pressed onto the adherend at a speed of 0.2 m / min through an ECS foam having a thickness of 10 mm as an adherend through a spacer having a thickness of 2 mm. paste.
- the spacer plays a role of preventing the adherend from being excessively compressed or insufficiently compressed.
- the sample piece attached to the adherend in this way is kept in an environment of 23 ° C. for 30 minutes after pressure bonding, it is placed in a measurement environment of 23 ° C. and 50% RH in accordance with JIS Z 0237 (2004). Then, the 180 ° peel adhesive strength is measured under the condition of a pulling speed of 300 mm / min. This measurement can be performed using a commercially available tensile tester.
- the measurement length (peeling length) is preferably 10 mm or more, and more preferably 20 mm or more. It is preferable to measure two or more times (more preferably three times or more) using different sample pieces and adopt an average value of the measurement results.
- the pressure-sensitive adhesive sheet does not peel at the interface with the adherend, but when the peel-off mode in which a part of the adherend is peeled off from the remainder together with the pressure-sensitive adhesive sheet, It can be estimated that the rough surface adhesion is at least 3.0 N / 20 mm or more.
- a pressure-sensitive adhesive sheet (typically, a double-sided pressure-sensitive adhesive sheet) that can be used for bonding an elastic foam such as a flexible urethane foam to an adherend, the surface of the adherend (curved surface) And the like, which can be elastically deformed along a stepped surface, etc.) and hold the foam in the elastically deformed shape against the repulsive force that the foam tries to return to its original shape (
- repulsion resistance that is, the ability to withstand the repulsion of the foam is required. Having such repulsion resistance is also preferable in a single-sided PSA sheet using a foamed sheet as a base material (support).
- the pressure-sensitive adhesive sheet satisfies the following property (B). That is, an adhesive sheet having a width of 10 mm and a length of 50 mm lined with an ECS foam having a thickness of 10 mm is used as a sample piece, and a portion from one end in the longitudinal direction of the sample piece to 10 mm is acrylonitrile-butadiene- with a thickness of 2 mm. After crimping to a styrene copolymer resin plate (ABS plate), the remaining part was folded and crimped from the end of the ABS plate to the other surface, and this was held in an environment of 23 ° C. and 50% RH for 24 hours.
- ABS plate styrene copolymer resin plate
- the floating distance is 3.5 mm or less (more preferably 3.0 mm or less, particularly preferably 1). 0.0 mm or less).
- the above repulsion resistance test can be performed, for example, as follows.
- an ECS foam having a thickness of 10 mm is bonded to the back surface of the pressure-sensitive adhesive sheet (the surface opposite to the pressure-sensitive adhesive surface that is the target of performance evaluation).
- the pressure-sensitive adhesive sheet is in the form of a double-sided pressure-sensitive adhesive sheet with no base material or a base material
- the ECS foam may be pressure-bonded to the pressure-sensitive adhesive surface opposite to the pressure-sensitive adhesive surface to be subjected to performance evaluation.
- a suitable double-sided pressure-sensitive adhesive tape (for example, a double-sided pressure-sensitive adhesive tape manufactured by Nitto Denko Corporation, trade name “No. 512”) is used on the back surface of the pressure-sensitive adhesive sheet.
- the ECS foam may be fixed.
- the ECS foam-attached pressure-sensitive adhesive sheet is cut into a strip shape having a width of 10 mm and a length of 50 mm to produce a sample piece. Using this sample piece, a repulsion resistance test is performed according to the procedure described in the examples described later.
- the pressure-sensitive adhesive sheet has the following property (C): in a holding force test performed by the method described in the examples described later, the holding time is 1 hour or more. Is satisfied. This holding force test is performed using two or more (more preferably three or more) different sample pieces. If even one sample piece falls within one hour, the holding force is insufficient (the holding time is one hour). Less). In the holding test, the sample piece is held even after 1 hour, and the adhesive sheet whose deviation width (average value of each sample piece) after 1 hour is 5 mm or less is more preferable, and the adhesive sheet that is 4 mm or less is further preferable.
- C the following property (C): in a holding force test performed by the method described in the examples described later, the holding time is 1 hour or more. Is satisfied. This holding force test is performed using two or more (more preferably three or more) different sample pieces. If even one sample piece falls within one hour, the holding force is insufficient (the holding time is one hour). Less). In the holding test, the sample piece is held even
- the pressure-sensitive adhesive sheet has the following characteristics (D): in the terminal peeling prevention test performed by the method described in the examples described later, the floating distance (average of both ends) Value) is 5 mm or less;
- the pressure-sensitive adhesive sheet having a floating distance of 4 mm or less is more preferred, and a pressure-sensitive adhesive sheet having a thickness of 3 mm or less (particularly preferably 2 mm or less, for example 1 mm or less) is more preferred.
- the monomer emulsion 70 parts of 2EHA, 30 parts of BA, 1.5 parts of AA, 2.5 parts of MAA, 3-methacryloxypropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., trade name “KBM-503”) 0.02 parts, n -0.033 part of lauryl mercaptan (chain transfer agent) and 2 parts of polyoxyethylene sodium lauryl sulfate (emulsifier) were added to 30 parts of ion-exchanged water and emulsified. After completion of the dropwise addition of the monomer emulsion, the obtained reaction mixture was kept at 60 ° C. for 3 hours.
- aqueous dispersion aqueous dispersion
- acrylic polymer pA X
- the gel fraction of the acrylic polymer contained in this emulsion eml1 was 40%. This gel fraction was calculated
- Mw of the THF soluble part of the said acrylic polymer was measured according to the method mentioned above, it was 80x10 ⁇ 4 >.
- Example 1 In a reaction vessel equipped with a cooling tube, a nitrogen introducing tube, a thermometer and a stirrer, 100 parts of BA, 10 parts of AA (having one carboxyl group per molecule as a functional group), 23 parts of tert-lauryl mercaptan, AIBN0 .2 parts and 200 parts of ethyl acetate were added, and the mixture was stirred at room temperature for 1 hour while introducing nitrogen gas. Then, while stirring, the temperature was raised to 60 ° C. and maintained at that temperature for 3 hours and then at 75 ° C. for 3 hours. did.
- an acrylic polymer (pA Y ) in which BA was the main monomer and AA was copolymerized as a functional group-containing monomer was prepared.
- This acrylic polymer (pA Y ) has a copolymer composition containing 91% BA and 9% AA with 100% of all monomer components.
- 20 parts of the above acrylic polymer solution and 20 parts of a tackifier are added to 100 parts of the polymer emulsion eml1 to form a water dispersion type adhesive.
- An agent composition was obtained.
- Polyacrylic acid as a thickener (trade name “Aron B-500”, manufactured by Toagosei Co., Ltd.) was added as appropriate to adjust the viscosity.
- MRF-38 was applied to one surface (peeled surface) and dried at 100 ° C. for 3 minutes to form an adhesive layer having a thickness of 80 ⁇ m, whereby an adhesive sheet according to this example was obtained.
- Example 2 An acrylic polymer solution was prepared in the same manner as in Example 1 except that the amount of AA was 20 parts.
- the copolymer composition of this acrylic polymer (pA Y ) is 83% BA and 17% AA.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 3 An acrylic polymer (copolymerization composition: BA 74%, AA 26%) solution was prepared in the same manner as in Example 1 except that the amount of AA was 35 parts.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 4 An acrylic polymer (copolymerization composition: BA 67%, AA 33%) solution was prepared in the same manner as in Example 1 except that the amount of AA was 50 parts. A pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 5 The product name “Aronix M5600” (acrylic acid dimer; having one carboxyl group per molecule as a functional group) manufactured by Toagosei Co., Ltd. instead of 10 parts of AA was used in the same manner as in Example 1. Then, an acrylic polymer (copolymerization composition; BA 77%, M5600 23%) solution was prepared. A pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used. ⁇ Example 6> An acrylic polymer (copolymerization composition: BA 71%, M5600 29%) solution was prepared in the same manner as in Example 5 except that the amount of M5600 was 40 parts.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 7 To 100 parts of the polymer emulsion eml1 on a solids basis, 20 parts of rosin resin (made by Arakawa Kogyo Co., Ltd., trade name “KE-802”) as a tackifier was added. A water-dispersed pressure-sensitive adhesive composition was obtained. A pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this water-dispersed pressure-sensitive adhesive composition was used.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 10 An acrylic polymer (copolymerization composition; BA 77%, M5300 23%) solution was prepared in the same manner as in Example 1 except that 30 parts of Aronix M5300 was used instead of 10 parts of AA.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 11 An acrylic polymer (copolymerization composition; BA 71%, M5300 29%) solution was prepared in the same manner as in Example 1 except that 40 parts of Aronix M5300 was used instead of 10 parts of AA.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 12 20 parts by trade name “SipomerPAM200” (mono [poly (propylene oxide) methacrylate) phosphate ester; mono-poly (propylene oxide) methacrylate] phosphate ester; one functional group having 1 phosphate group) instead of 10 parts AA
- Acrylic polymer (copolymerization composition; BA 83%, PAM200 17%) solution was prepared in the same manner as in Example 1 except that was used.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 13 An acrylic polymer (copolymerization composition; BA 77%, PAM200 23%) solution was prepared in the same manner as in Example 1 except that 30 parts of SipomerPAM200 was used instead of 10 parts of AA.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 14> A pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that the blending amount of the acrylic polymer solution per 100 parts of the polymer emulsion eml1 was changed to 5 parts (all based on solid content) instead of 20 parts.
- Example 15> A pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that the amount of the acrylic polymer solution per 100 parts of the polymer emulsion eml1 was changed to 20 parts instead of 20 parts (both based on solid content).
- Example 1 except that this polymer solution (copolymerization composition; BA 83%, AA 17%) was used, and the blending amount of the polymer solution per 100 parts of the polymer emulsion eml1 was 5 parts (both based on solid content).
- the pressure-sensitive adhesive sheet according to this example was obtained.
- Example 17> A pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 16 except that the blending amount of the polymer solution per 100 parts of the polymer emulsion eml1 was 40 parts (all based on solid content).
- Example 18 A pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 15 except that the polymer solution according to Example 6 was used instead of the polymer solution according to Example 1.
- Example 19 An acrylic polymer (copolymerization composition; BA 83%, AA 17%) solution was prepared in the same manner as in Example 1 except that the amount of AA was 20 parts and the amount of tert-lauryl mercaptan was 0.5 parts. .
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 20 An acrylic polymer (copolymerization composition; EA 92) was used in the same manner as in Example 1 except that ethyl acrylate (EA) was used instead of BA, the amount of AA was 11 parts, and the amount of tert-lauryl mercaptan was 15 parts. %, AA 8%) solution was prepared.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Example 21 Using 83 parts of BA and 17 parts of styrene instead of 100 parts of BA, using 11 parts of MAA (having one carboxyl group per molecule as a functional group) instead of 10 parts of AA, the amount of tert-lauryl mercaptan was determined.
- An acrylic polymer (copolymerization composition: BA 76%, styrene 16%, MAA 8%) solution was prepared in the same manner as in Example 1 except that the amount was 3 parts.
- a pressure-sensitive adhesive sheet according to this example was obtained in the same manner as in Example 1 except that this polymer solution was used.
- Table 1 shows the characteristics of the acrylic polymer (polymer corresponding to pA Y ) contained in the polymer solution used for the water-dispersed pressure-sensitive adhesive compositions according to Examples 1 to 21.
- Tg as described above, the value calculated from the Fox equation based on the Tg of the homopolymer of each monomer and the mass fraction of the monomer was described.
- ⁇ Rough surface adhesion evaluation> As the adherend, a 10 mm thick flexible urethane foam (trade name “ECS” (gray) of Inoac Corporation) was cut to a size of 30 mm width and 100 mm length. Under an environment of 23 ° C., a polyethylene terephthalate (PET) film having a thickness of 25 ⁇ m was attached to one adhesive surface of each adhesive sheet prepared in Examples 1 to 21 and backed. A sample piece was prepared by cutting the backed adhesive sheet into a size of 20 mm in width and 100 mm in length.
- ECS polyethylene terephthalate
- the release liner was peeled from the sample piece, and this was pressure-bonded to the adherend at a speed of 0.2 m / min using a laminator through a spacer having a thickness of 2 mm. This was held at 23 ° C. for 30 minutes, and then pulled 180 ° under a tensile speed of 300 mm / min in a measurement environment of 23 ° C. and 50% RH using a tensile tester in accordance with JIS Z 0237 (2004). The peel adhesive strength (rough surface adhesive strength) was measured. The measurement length was at least 10 mm. Three sample pieces were prepared from the pressure-sensitive adhesive sheet according to each example, and the average value of three measurement results using them was calculated.
- the release liner is peeled off from the other adhesive surface of the sample piece 50, and a portion from the one end 50 ⁇ / b> A to 10 mm in the longitudinal direction of the adhesive surface thus exposed (that is, an adhesive having a width of 10 mm and a length of 10 mm). Area) was crimped to the outer edge of one surface 52A of the 2 mm thick ABS plate 52 by reciprocating a 2 kg roller. At this time, the position of 10 mm from one end 50 ⁇ / b> A of the sample piece 50 is aligned with the outer peripheral end of the ABS plate 52, and the sample piece 50 is arranged so that the remaining part of the sample piece 50 extends perpendicularly outward from the ABS plate 52.
- reference numeral 502 indicates an adhesive sheet
- reference numeral 504 indicates a urethane foam that is pressure-bonded to one adhesive surface of the adhesive sheet. This was left for 24 hours in an environment of 23 ° C. and 50% RH, and then the floating distance of one end 50A of the sample piece 50 was measured. Three sample pieces were produced from the pressure-sensitive adhesive sheet according to each example, and the average value of the floating distances of these sample pieces was calculated. In addition, when the sample piece 50 completely peels from the surface 52A, Table 2 shows “peeling”.
- ⁇ Retention force test> A holding force test was performed according to JIS Z 0237 (2004). That is, in an environment of 23 ° C., a PET film having a thickness of 25 ⁇ m was attached to one adhesive surface of each adhesive sheet and backed. The backing adhesive sheet was cut into a width of 10 mm to prepare a sample piece. The release liner was peeled off from the other pressure-sensitive adhesive surface of the sample piece, and the pressure-sensitive adhesive surface thus exposed was affixed to a phenol resin plate as an adherend with an adhesive area of 10 mm width and 20 mm length. This was allowed to stand in an environment of 40 ° C.
- the phenol resin plate was suspended to give a load of 500 g to the free end (lower end) of the sample piece.
- the sample was left in an environment of 40 ° C. for 1 hour with the load applied.
- the displacement distance (mm) of the sample piece from the initial attachment position was measured.
- Three sample pieces were produced from the pressure-sensitive adhesive sheet according to each example, and the holding force test was performed on each sample piece. When one of the three sample pieces dropped after 1 hour, it was determined that the holding time was less than 1 hour (shown as “falling” in Table 2). In other cases, the deviation distance (mm) of the sample piece from the first attachment position was measured for each of the three sample pieces, and the average value thereof was calculated.
- Each adhesive sheet is cut into a size of 10 mm in width and 90 mm in length, and the adhesive surface is attached to an aluminum piece (thickness 0.4 mm, width 10 mm, length 90 mm) cut into the same size to produce a sample piece. did.
- the longitudinal direction of the sample piece was wound around a cylinder with a diameter of 50 mm so that the aluminum piece side was on the inside, and was bent in an arc shape by pressing for about 10 seconds.
- the release liner was peeled from the sample piece, and the exposed adhesive surface was pressure-bonded to a PP plate (thickness 2 mm) with a laminator. After holding this in an environment of 23 ° C.
- Example 1 using an adhesive composition containing a polymer corresponding to pA Y in addition to a polymer corresponding to pA X and N satisfying 0.12 ⁇ N ⁇ 0.50
- Each of the pressure-sensitive adhesive sheets according to 6 to 6 exhibited a rough surface adhesive force exceeding 3.5 N / 20 mm, and at the same time was excellent in repulsion resistance, holding power, and terminal peeling prevention.
- the pressure-sensitive adhesive sheet of Example 7 obtained by using a pressure-sensitive adhesive composition containing no polymer corresponding to pA Y is rough surface adhesiveness strength was extremely low as 0.3 N / 20 mm. Even in the pressure-sensitive adhesive sheet of Example 8 using an acrylic polymer that does not contain a functional group-containing monomer as a constituent component instead of the polymer corresponding to pA Y , sufficient rough surface adhesion was not realized. Further, the pressure-sensitive adhesive sheets of Examples 9 to 13 and 21 using a low molecular weight polymer that does not satisfy 0.12 ⁇ N ⁇ 0.50 as the polymer corresponding to pA Y are rougher than those of Examples 1 to 6.
- the pressure-sensitive adhesive sheet of Example 20 in which the Tg of the low molecular weight polymer is higher than ⁇ 15 ° C. was also clearly lower in rough surface adhesion than Examples 1 to 6.
- the pressure-sensitive adhesive sheets of Examples 14 and 16 in which the blending amount of the polymer pA Y was less than 5%, the effect of improving the rough surface adhesion was insufficient.
- the pressure-sensitive adhesive sheet of Example 15, 17, 18 formed by using an adhesive composition amount of polymer pA Y is too large, the holding power and edge peeling resistance resulted to decrease.
- the pressure-sensitive adhesive sheet of Example 19 containing a sufficient amount of functional group-containing monomer (AA) as a constituent component but having a Mw of 142000 and a polymer that is larger than the desired range was sufficiently rough. Surface adhesion was not realized.
- Adhesive sheet 10 Base material 10A: Surface of base material (non-peelable) 21, 22: Adhesive layer 21A, 21B: Adhesive surface 31, 32: Release liner 50: Sample piece 50A: One end 502: Adhesive sheet 504: Urethane foam 52: ABS plate 52A: One surface 52B: The other surface
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Adhesives Or Adhesive Processes (AREA)
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- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
Description
CH2=C(R1)COOR2 (II)
(式中、R1は水素原子またはメチル基であり、R2はC1-18のアルキル基である。)
<ポリマーpAXのMwを測定する方法>
測定対象たるアクリル系ポリマーpAXのサンプルを23℃にてTHF中に7日間浸漬してTHF可溶分を溶出させる。THF不溶分を濾過によって除去し、得られた濾液を必要に応じて濃縮あるいはTHFで希釈して、THF可溶分を0.1~0.3質量%程度の濃度で含むTHF溶液を調製する。このTHF溶液を平均孔径が0.45μmのフィルターで濾過して得られた濾液につき、ゲルパーミエーションクロマトグラフィ(GPC)装置により標準ポリスチレン基準の重量平均分子量Mwを求める。GPC装置としては、例えば、東ソー株式会社製の型式「HLC-8320GPC」(カラム:TSKgel GMH-H(S))またはこれに準ずる精度の装置を使用することができる。上記アクリル系ポリマーpAXのサンプルとしては、エマルション重合により得られたポリマーpAXを乾燥(例えば、130℃で2時間程度乾燥)させたものを用いるとよい。
<ポリマーpAYのMwを測定する方法>
測定対象たるアクリル系ポリマーpAYを10mM-LiBr+10mMリン酸/DMF(希釈液)中に0.1~0.3質量%程度(例えば0.2質量%)の濃度で含む測定用溶液を調製する。このTHF溶液を平均孔径0.45μmのフィルターで濾過した濾液につき、GPC装置により標準ポリスチレン基準の重量平均分子量Mwを求める。GPC装置としては、例えば、東ソー株式会社製の型式「HLC-8120GPC」またはこれに準ずる精度の装置を使用することができる。具体的には、後述する実施例に記載のMw測定条件を適用してポリマーpAYのMwを測定することができる。なお、ポリマーpAYを溶液重合により合成した場合、上記測定用溶液としては、例えば、重合反応液(典型的には、ポリマーpAYを20質量%以上の濃度で含む溶液)を上記希釈液で希釈して調製したものを用いることができる。また、ポリマーpAYの一部がTHFに溶解しない場合には、ポリマーpAXの場合と同様に、ポリマーpAYを23℃にてTHF中に7日間浸漬して抽出した可溶分について標準ポリスチレン基準の重量平均分子量Mwを求めるものとする。
2-エチルヘキシルアクリレート -70℃
ブチルアクリレート -55℃
エチルアクリレート -22℃
メチルアクリレート 8℃
メチルメタクリレート 105℃
シクロヘキシルメタクリレート 66℃
酢酸ビニル 32℃
スチレン 100℃
アクリル酸 106℃
メタクリル酸 130℃
PAM200(商品名) 0℃
M5600(商品名) 12℃
M5300(商品名) -35℃
重合を行う際のモノマー供給方法としては、上述した一括仕込み方式、連続供給(滴下)方式、分割供給(滴下)方式等を適宜採用することができる。モノマーの一部または全部(典型的には全部)をあらかじめ溶媒に溶解または分散させ、その溶液を反応容器内に一括、連続あるいは分割して供給してもよい。重合温度は、使用するモノマーの種類、重合開始剤の種類等に応じて適宜選択することができ、例えば20℃~100℃(典型的には40℃~80℃)程度とすることができる。重合時間(反応時間)は、例えば1~12時間(典型的には4~12時間)とすることができる。
かかる重合によって得られたアクリル系ポリマーpAYは、必要に応じて適当な後処理を施した後、上記ポリマーpAXの水性エマルションに添加することができる。これによりpAXとpAYとを含む水性エマルションを調製することができる。例えば、バルク重合や光重合等により揮発分を実質的に含まない形態のポリマーpAYが得られた場合には、(1)該ポリマーpAYをそのままpAXの水性エマルションに添加して攪拌混合する方法のほか、(2)該ポリマーpAYを水と乳化剤とともに強く攪拌してpAYの水性エマルションを調製する後処理を行い、これをpAXの水性エマルションに添加する方法等を採用することができる。また、ポリマーpAYを溶液重合により合成した場合や上述のようにバルク重合後に内容物の取出しを容易とする等の目的で少量の有機溶剤を添加した場合等、有機溶剤を含む形態のpAYが得られた場合には、(3)該ポリマーpAYをそのままpAXの水性エマルションに添加して攪拌混合する方法のほか、(4)該ポリマーpAYを水と乳化剤とともに強く攪拌してpAYの水性エマルションを調製する後処理を行い、これをpAXの水性エマルションに添加する方法、(5)上記(4)で調製したpAYの水性エマルションに対し、該エマルションを減圧して有機溶剤を除去する後処理をさらに行い、これをpAXの水性エマルションに添加する方法等を採用することができる。エマルション重合によりポリマーpAYを得た場合には、これをそのままpAXの水性エマルションに添加する方法を好ましく採用することができる。
SP=(Ev/v)1/2=(ΣΔei/ΣΔvi)1/2
ここで、Evは蒸発エネルギー、vはモル体積、Δeiは各原子または原子団の蒸発エネルギー、Δviは各原子または原子団のモル体積である;を用いて算出される値を採用するものとする。2種以上のC2-18アルキル(メタ)アクリレートを含む共重合組成のアクリル系ポリマーについては、各C2-18アルキル(メタ)アクリレートのホモポリマーのSP値に、該C2-18アルキル(メタ)アクリレートのモル分率(すなわち、当該C2-18アルキル(メタ)アクリレートのモル数が全C2-18アルキル(メタ)アクリレートの合計モル数に占める割合)を乗じ、それらの値を合計することにより、そのアクリル系ポリマーを構成するC2-18アルキル(メタ)アクリレートについてのSP値を算出することができる。
ここで「粘着剤のゲル分率」とは、次の方法により測定される値をいう。該ゲル分率は、粘着剤のうち酢酸エチル不溶分の質量割合として把握され得る。
粘着剤サンプル(質量Wg1)を平均孔径0.2μmの多孔質ポリテトラフルオロエチレン膜(質量Wg2)で巾着状に包み、口をタコ糸(質量Wg3)で縛る。この包みを酢酸エチル50mLに浸し、室温(典型的には23℃)で7日間保持して粘着剤層中のゾル成分のみを上記膜外に溶出させた後、上記包みを取り出して外表面に付着している酢酸エチルを拭き取り、該包みを130℃で2時間乾燥させ、該包みの質量(Wg4)を測定する。粘着剤のゲル分率FGは、各値を以下の式に代入することにより求められる。
ゲル分率FG(%)=[(Wg4-Wg2-Wg3)/Wg1]×100
冷却管、窒素導入管、温度計および攪拌機を備えた反応容器にイオン交換水40部を入れ、窒素ガスを導入しながら室温にて1時間以上攪拌した。次いで、この反応容器に2,2’-アゾビス[N-(2-カルボキシエチル)-2-メチルプロピオンアミジン]水和物(重合開始剤)(和光純薬工業株式会社製,商品名「VA-057」)0.1部を投入し、系を60℃に保ちつつ、ここにモノマーエマルションを3時間かけて徐々に滴下した。モノマーエマルションとしては、2EHA70部、BA30部、AA1.5部、MAA2.5部、3-メタクリロキシプロピルトリメトキシシラン(信越化学工業株式会社,商品名「KBM-503」)0.02部、n-ラウリルメルカプタン(連鎖移動剤)0.033部およびポリオキシエチレンラウリル硫酸ナトリウム(乳化剤)2部を、イオン交換水30部に添加して乳化したものを使用した。モノマーエマルションの滴下終了後、得られた反応混合物をさらに3時間60℃に保持した。系を常温まで冷却した後、10%アンモニウム水の添加によりpH7.5に調整して、アクリル系ポリマー(pAX)の水性エマルション(水分散液)eml1を得た。
このエマルションeml1に含まれるアクリル系ポリマーのゲル分率は40%であった。このゲル分率は、エマルションeml1を130℃で2時間乾燥させたサンプルにつき、上述したゲル分率測定方法を適用することにより求めた。また、上述した方法に従って上記アクリル系ポリマーのTHF可溶分のMwを測定したところ、80×104であった。
冷却管、窒素導入管、温度計および攪拌機を備えた反応容器に、BA100部、AA(官能基として、一分子当たり1個のカルボキシル基を有する。)10部、tert―ラウリルメルカプタン23部、AIBN0.2部、酢酸エチル200部を加え、窒素ガスを導入しながら室温にて1時間攪拌した後、引き続き攪拌しながら60℃に昇温して該温度に3時間、次いで75℃に3時間保持した。このようにして、BAを主モノマーとし、官能基含有モノマーとしてAAが共重合されたアクリル系ポリマー(pAY)の溶液を調製した。このアクリル系ポリマー(pAY)は、全モノマー成分を100%として、BAを91%、AAを9%含む共重合組成を有する。
固形分基準で、100部のポリマーエマルションeml1に対して、20部の上記アクリル系ポリマー溶液と、20部の粘着付与剤(軟化点170℃の重合ロジンエステル)とを加えて、水分散型粘着剤組成物を得た。これに増粘剤としてのポリアクリル酸(東亞合成株式会社製,商品名「アロンB-500」)を適宜加えて粘度調整したものを、剥離ライナー(三菱樹脂株式会社製、商品名「ダイヤホイルMRF-38」)の一方の面(剥離面)に付与し、100℃で3分間乾燥させて厚み80μmの粘着剤層を形成し、本例に係る粘着シートを得た。
AAの量を20部とした他は例1と同様にして、アクリル系ポリマー溶液を調製した。このアクリル系ポリマー(pAY)の共重合組成は、BA 83%、AA 17%である。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例3>
AAの量を35部とした他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 74%、AA 26%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例4>
AAの量を50部とした他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 67%、AA 33%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
AA10部に代えて東亞合成株式会社製の商品名「アロニックスM5600」(アクリル酸ダイマー;官能基として、一分子当たり1個のカルボキシル基を有する。)30部を用いた他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 77%、M5600 23%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例6>
M5600の量を40部とした他は例5と同様にして、アクリル系ポリマー(共重合組成;BA 71%、M5600 29%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例7>
固形分基準で、100部のポリマーエマルションeml1に対し、粘着付与剤として20部(いずれも固形分基準)のロジン系樹脂(荒川工業株式会社製,商品名「KE-802」)を加えて、水分散型粘着剤組成物を得た。この水分散型粘着剤組成物を用いた他は例1と同様にして、本例に係る粘着シートを得た。
AAを使用しなかった他は例1と同様にして、アクリル系ポリマー溶液(重合組成;BA 100%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例9>
AA10部に代えて東亞合成株式会社製の商品名「アロニックスM5300」(ω-カルボキシ-ポリカプロラクトンモノアクリレート;官能基として、一分子当たり1個のカルボキシル基を有する。)20部を用いた他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 83%、M5300 17%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例10>
AA10部に代えてアロニックスM5300 30部を用いた他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 77%、M5300 23%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
AA10部に代えてアロニックスM5300 40部を用いた他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 71%、M5300 29%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例12>
AA10部に代えてローディア日華株式会社製の商品名「SipomerPAM200」(モノ[ポリ(プロピレンオキシド)メタクリレート]リン酸エステル;官能基として、一分子当たり1個のリン酸基を有する。)20部を用いた他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 83%、PAM200 17%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例13>
AA10部に代えてSipomerPAM200 30部を用いた他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 77%、PAM200 23%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
ポリマーエマルションeml1 100部当たりのアクリル系ポリマー溶液の配合量を20部に代えて5部(いずれも固形分基準)とした他は例1と同様にして、本例に係る粘着シートを得た。
<例15>
ポリマーエマルションeml1 100部当たりのアクリル系ポリマー溶液の配合量を20部に代えて40部(いずれも固形分基準)とした他は例1と同様にして、本例に係る粘着シートを得た。
<例16>
AAの量を20部とした他は例1と同様にして、アクリル系ポリマー溶液を調製した。このポリマー溶液(共重合組成;BA 83%、AA 17%)を用い、且つポリマーエマルションeml1 100部当たりの該ポリマー溶液の配合量を5部(いずれも固形分基準)とした他は例1と同様にして、本例に係る粘着シートを得た。
<例17>
ポリマーエマルションeml1 100部当たりのポリマー溶液の配合量を40部(いずれも固形分基準)とした他は例16と同様にして、本例に係る粘着シートを得た。
例1に係るポリマー溶液に代えて例6に係るポリマー溶液を用いた他は例15と同様にして、本例に係る粘着シートを得た。
<例19>
AAの量を20部とし、tert―ラウリルメルカプタンの量を0.5部とした他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 83%、AA 17%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例20>
BAに代えてエチルアクリレート(EA)を用い、AAの量を11部とし、tert―ラウリルメルカプタンの量を15部とした他は例1と同様にして、アクリル系ポリマー(共重合組成;EA 92%、AA 8%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
<例21>
BA100部に代えてBA83部とスチレン17部とを用い、AA10部に代えてMAA(官能基として、一分子当たり1個のカルボキシル基を有する。)11部を用い、tert―ラウリルメルカプタンの量を3部とした他は例1と同様にして、アクリル系ポリマー(共重合組成;BA 76%、スチレン 16%、MAA 8%)溶液を調製した。このポリマー溶液を用いた他は例1と同様にして、本例に係る粘着シートを得た。
各例において使用したアクリル系ポリマー溶液に含まれるアクリル系ポリマー(pAY)につき、該ポリマーを10mM-LiBr+10mMリン酸/DMF中に0.2%の濃度で含む測定用溶液を調製し、ゲルパーミエーションクロマトグラフィ(GPC)法に従い、下記条件にてポリスチレン校正曲線に基づく重量平均分子量(Mw)を算出した。
装置:TOSOH社製の型式「HLC-8120GPC」
カラム:TSKgel superAWM-H,
TSKgel superAW4000,
TSKgel superAW2500の3本を連結
カラム温度:40℃
流量:0.4mL/分
上述した方法に従って、各例に係る粘着剤のゲル分率FGを測定した。
被着体として、厚さ10mmの軟質ウレタンフォーム(株式会社イノアックコーポレーションの商品名「ECS」(灰色))を幅30mm、長さ100mmのサイズにカットしたものを用意した。
23℃の環境下において、例1~21において作製した各粘着シートの一方の粘着面に厚さ25μmのポリエチレンテレフタレート(PET)フィルムを貼り付けて裏打ちした。この裏打ちされた粘着シートを幅20mm、長さ100mmのサイズにカットしたものを試料片とした。この試料片から剥離ライナーを剥がし、これを上記被着体に、厚さ2mmのスペーサーを介して、ラミネータを用いて0.2m/分の速度で圧着した。これを23℃に30分間保持した後、JIS Z 0237(2004)に準拠し、引張試験機を用いて、23℃、50%RHの測定環境にて引張速度300mm/分の条件で180°引き剥がし粘着力(粗面接着力)を測定した。測定長さは少なくとも10mm以上とした。各例に係る粘着シートからそれぞれ3つの試料片を作製し、それらを用いた3回の測定結果の平均値を算出した。
23℃の環境下において、各粘着シートの一方の粘着面を、厚さ10mmの軟質ウレタンフォーム(株式会社イノアックコーポレーションの商品名「ECS」(灰色))に、1kgのローラを一往復させて圧着した。これを23℃に1日間保持した後、幅10mm、長さ50mmに裁断して試料片を作製した。
JIS Z 0237(2004)に準拠して保持力試験を行った。すなわち、23℃の環境下において、各粘着シートの一方の粘着面に厚さ25μmのPETフィルムを貼り付けて裏打ちした。この裏打ちされた粘着シートを幅10mmにカットして試料片を作製した。該試料片の他方の粘着面から剥離ライナーを剥がし、これにより露出した粘着面を、被着体としてのフェノール樹脂板に、幅10mm、長さ20mmの接着面積にて貼り付けた。これを40℃の環境下に30分間放置した後、フェノール樹脂板を垂下し、試料片の自由端(下端)に500gの荷重を付与した。上記荷重が付与された状態で40℃の環境下に1時間放置した。最初の貼り付け位置からの試料片のズレ距離(mm)を測定した。各例に係る粘着シートからそれぞれ3つの試料片を作製し、それぞれの試料片に対して当該保持力試験を行った。1時間経過後、3つの試料片のうち一つでも試料片が落下した場合には、保持時間1時間未満と判定した(表2では「落下」と示している。)。それ以外の場合には、3つの試料片につき、それぞれ最初の貼り付け位置からの試料片のズレ距離(mm)を測定し、それらの平均値を算出した。
各粘着シートを幅10mm、長さ90mmのサイズにカットし、その粘着面を、同じサイズにカットしたアルミニウム片(厚さ0.4mm,幅10mm,長さ90mm)に貼り付けて試料片を作製した。この試料片の長手方向を、アルミニウム片側が内側となるようにして直径50mmの円柱に巻きつけ、約10秒間押しつけることにより円弧状に反らせた。この試料片から剥離ライナーを剥がし、露出した粘着面をラミネータでPP板(厚さ2mm)に圧着した。これを23℃、RH50%の環境下に24時間保持した後に、該試料片の長手方向の両端部について、各端部がPP板表面から浮きあがった高さ(PP板表面から試料片端部までの距離)(mm)をそれぞれ測定した。各例に係る粘着シートからそれぞれ3つの試料片を作製し、それらの試料片の両端、合計6箇所についての測定結果の平均値を算出した。その結果(浮き距離)を、端末剥がれ防止性を示す特性値として表2に示した。なお、上記平均値が5mmを超える値であった場合には、表2において「剥離」と表示した。
10:基材
10A:基材の表面(非剥離性)
21,22:粘着剤層
21A,21B:粘着面
31,32:剥離ライナー
50:試料片
50A:一端
502:粘着シート
504:ウレタンフォーム
52:ABS板
52A:一方の表面
52B:他方の表面
Claims (9)
- 水性溶媒中にアクリル系ポリマーpAXとアクリル系ポリマーpAYとを含む水分散型粘着剤組成物であって、
前記ポリマーpAXと前記ポリマーpAYとの質量比は100:6~100:35であり、
前記ポリマーpAXは、アルキル基の炭素原子数が1~18であるアルキル(メタ)アクリレートM1Xを主モノマーとして含み、
前記ポリマーpAYは、重量平均分子量Mwが1×103~50×103であり、ガラス転移温度が-15℃以下であり、該ポリマーを構成するモノマーとして、アルキル基の炭素原子数が1~18であるアルキル(メタ)アクリレートM1Yと、官能基含有モノマーM2Yとを少なくとも含む共重合組成を有し、
前記ポリマーpAYに含まれる前記モノマーM2Y由来の官能基数Nは、当該ポリマーpAY100g当たり、0.12molより大きく且つ0.50mol以下である、
水分散型粘着剤組成物。 - 前記モノマーM2Yは、カルボキシル基含有モノマーの少なくとも一種を含む、請求項1に記載の水分散型粘着剤組成物。
- 前記モノマーM2Yは、アクリル酸およびアクリル酸ダイマーの少なくとも一方を含む、請求項1または2に記載の水分散型粘着剤組成物。
- 前記ポリマーpAXは、テトラヒドロフラン可溶分の重量平均分子量Mwが30×104~100×104である、請求項1から3のいずれか一項に記載の水分散型粘着剤組成物。
- 前記ポリマーpAXは、2-エチルヘキシルアクリレートを少なくとも50質量%含む共重合組成を有し、前記ポリマーpAYは、ブチルアクリレートを少なくとも50質量%含む共重合組成を有する、請求項1から4のいずれか一項に記載の水分散型粘着剤組成物。
- 前記ポリマーpAX100質量部に対し、5~40質量部の粘着付与剤をさらに含む、請求項1から5のいずれか一項に記載の水分散型粘着剤組成物。
- 前記粘着付与剤がロジン系樹脂である、請求項6に記載の水分散型粘着剤組成物。
- 前記水分散型粘着剤組成物から形成される粘着剤に占める酢酸エチル不溶分の質量割合が20~55%である、請求項1から7のいずれか一項に記載される水分散型粘着剤組成物。
- 請求項1から8のいずれか一項に記載される水分散型粘着剤組成物から形成された粘着剤層を有する粘着シート。
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KR1020127025241A KR20130131210A (ko) | 2011-03-09 | 2012-01-16 | 수분산형 점착제 조성물 및 점착 시트 |
CN2012800010233A CN102822299A (zh) | 2011-03-09 | 2012-01-16 | 水分散型粘合剂组合物和粘合片 |
US13/638,402 US20130023615A1 (en) | 2011-03-09 | 2012-01-16 | Water-dispersed pressure-sensitive adhesive composition and pressure-sensitive adhesive sheet |
EP12754994.7A EP2684929A1 (en) | 2011-03-09 | 2012-01-16 | Aqueous dispersion adhesive composition and adhesive sheet |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015101644A (ja) * | 2013-11-25 | 2015-06-04 | 日東電工株式会社 | 粘着シート |
WO2015151954A1 (ja) * | 2014-04-03 | 2015-10-08 | 積水化学工業株式会社 | 両面粘着テープ |
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CN104099038B (zh) * | 2013-04-07 | 2017-12-26 | 广东多正树脂科技有限公司 | 用于聚氨酯泡沫材料的快干接触型胶黏剂及其制备方法 |
JP6303345B2 (ja) * | 2013-09-09 | 2018-04-04 | Dic株式会社 | 熱伝導シート、物品及び電子部材 |
JP6931629B2 (ja) * | 2014-07-16 | 2021-09-08 | 日東電工株式会社 | 積層光学フィルムの製造方法 |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS568476A (en) | 1979-06-30 | 1981-01-28 | Nitto Electric Ind Co Ltd | Water-dispersible pressure-sensitive adhesive composition |
JPS63241084A (ja) * | 1987-03-27 | 1988-10-06 | Japan Synthetic Rubber Co Ltd | エマルジヨン型感圧接着剤 |
JPH05230428A (ja) * | 1992-02-21 | 1993-09-07 | Nitto Denko Corp | 水分散型感圧接着剤組成物 |
JP2002265907A (ja) * | 2001-03-13 | 2002-09-18 | Mitsubishi Chemicals Corp | 粘着剤組成物及び粘着テープ又はラベル |
JP2003213244A (ja) * | 2002-01-29 | 2003-07-30 | Dainippon Ink & Chem Inc | 水性粘着剤組成物およびその製造方法 |
JP2004002525A (ja) * | 2002-05-31 | 2004-01-08 | Dainippon Ink & Chem Inc | 水性粘着剤組成物およびその製造方法 |
JP2005170990A (ja) * | 2003-12-08 | 2005-06-30 | Nitto Denko Corp | 粘着テープ |
JP2010018689A (ja) | 2008-07-09 | 2010-01-28 | Showa Highpolymer Co Ltd | 水性粘着剤組成物及びこれを用いた粘着シート |
JP2011052078A (ja) | 2009-08-31 | 2011-03-17 | Toyobo Co Ltd | 高分子電解質組成物、高分子電解質膜、及び燃料電池 |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100668943B1 (ko) * | 2004-04-23 | 2007-01-12 | 주식회사 엘지화학 | 편광판용 아크릴계 점착제 조성물 |
US7858709B2 (en) * | 2007-05-02 | 2010-12-28 | Nitto Denko Corporation | Aqueous dispersion adhesive composition and adhesive film |
-
2011
- 2011-03-09 JP JP2011052078A patent/JP2012188513A/ja active Pending
-
2012
- 2012-01-16 WO PCT/JP2012/050714 patent/WO2012120921A1/ja active Application Filing
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- 2012-01-16 EP EP12754994.7A patent/EP2684929A1/en not_active Withdrawn
- 2012-01-16 US US13/638,402 patent/US20130023615A1/en not_active Abandoned
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS568476A (en) | 1979-06-30 | 1981-01-28 | Nitto Electric Ind Co Ltd | Water-dispersible pressure-sensitive adhesive composition |
JPS63241084A (ja) * | 1987-03-27 | 1988-10-06 | Japan Synthetic Rubber Co Ltd | エマルジヨン型感圧接着剤 |
JPH05230428A (ja) * | 1992-02-21 | 1993-09-07 | Nitto Denko Corp | 水分散型感圧接着剤組成物 |
JP2002265907A (ja) * | 2001-03-13 | 2002-09-18 | Mitsubishi Chemicals Corp | 粘着剤組成物及び粘着テープ又はラベル |
JP2003213244A (ja) * | 2002-01-29 | 2003-07-30 | Dainippon Ink & Chem Inc | 水性粘着剤組成物およびその製造方法 |
JP2004002525A (ja) * | 2002-05-31 | 2004-01-08 | Dainippon Ink & Chem Inc | 水性粘着剤組成物およびその製造方法 |
JP2005170990A (ja) * | 2003-12-08 | 2005-06-30 | Nitto Denko Corp | 粘着テープ |
JP2010018689A (ja) | 2008-07-09 | 2010-01-28 | Showa Highpolymer Co Ltd | 水性粘着剤組成物及びこれを用いた粘着シート |
JP2011052078A (ja) | 2009-08-31 | 2011-03-17 | Toyobo Co Ltd | 高分子電解質組成物、高分子電解質膜、及び燃料電池 |
Non-Patent Citations (1)
Title |
---|
JOURNAL OF THE ADHESION SOCIETY OF JAPAN, vol. 22, no. 10, 1986, pages 566 |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015101644A (ja) * | 2013-11-25 | 2015-06-04 | 日東電工株式会社 | 粘着シート |
WO2015151954A1 (ja) * | 2014-04-03 | 2015-10-08 | 積水化学工業株式会社 | 両面粘着テープ |
CN105745295A (zh) * | 2014-04-03 | 2016-07-06 | 积水化学工业株式会社 | 双面粘接带 |
JPWO2015151954A1 (ja) * | 2014-04-03 | 2017-04-13 | 積水化学工業株式会社 | 両面粘着テープ |
CN105745295B (zh) * | 2014-04-03 | 2020-06-30 | 积水化学工业株式会社 | 双面粘接带 |
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JP2012188513A (ja) | 2012-10-04 |
EP2684929A1 (en) | 2014-01-15 |
US20130023615A1 (en) | 2013-01-24 |
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