JP6635699B2 - Antistatic agent and adhesive composition - Google Patents

Description

  The present invention relates to an antistatic agent capable of imparting an antistatic property to an adhesive, and an adhesive composition containing the same. More specifically, it is excellent in antistatic properties, and can be suitably used as an antistatic agent for an adhesive without deteriorating the antistatic performance even in applications that come into contact with water, without contaminating the adherend. The present invention relates to an agent and a pressure-sensitive adhesive composition containing the same.

Conventionally, pressure-sensitive adhesives intended for antistatic properties when peeled from an adherend include, for example, polyether polyols (for example, Patent Document 1), surfactants (for example, Patent Document 2), An adhesive or the like to which an antistatic agent such as a system conductive filler and carbon black (for example, Patent Document 3) is added is known.
However, conventionally, these pressure-sensitive adhesives have problems such as contamination of the adherend surface due to bleed-out of the antistatic agent and deterioration of the adhesive properties over time. In addition, some of the adhesives to which these antistatic agents are added contain a large amount of impurities that may cause corrosion, malfunction, or malfunction inside the electronic device. There is also the problem of difficulty. In addition, in the case of a process adhesive tape application in the semiconductor manufacturing process field, there is a step of cleaning a wafer with an aqueous solution with an aqueous solution, and there is a step of contacting with water, so that the antistatic performance does not change before and after the cleaning step. Needed.

In addition, there is a demand to further reduce the occurrence rate of defective products such as suction of surrounding dust or electrostatic breakdown caused by static electricity in electronic device manufacturing and the like. However, the antistatic property is insufficient, and further improvement of the antistatic property is required.
With respect to these problems, for example, a pressure-sensitive adhesive to which a metal-based conductive filler or carbon black antistatic agent is added has a problem that even if the antistatic property can be satisfied, there is no transparency. Further, for example, it is extremely difficult to realize an antistatic property having a surface resistivity of less than 1011 Ω / □ without causing contamination of an adherend with a pressure-sensitive adhesive to which an antistatic agent such as a polyether polyol or a surfactant is added. There is a problem.

  Examples of pressure-sensitive adhesives that solve these problems include, for example, alkylene oxide groups (for example, Patent Document 4) and quaternary ammonium bases (for example, Patent Documents 5 and 6) on the molecular side chains and / or molecular terminals of the acrylic copolymer. There is disclosed a pressure-sensitive adhesive composed of a resin having antistatic properties. These pressure-sensitive adhesives can realize an antistatic property having a surface resistivity of less than 1011 Ω / □ without causing contamination of an adherend by incorporating an antistatic component into the polymer structure.

JP-A-6-128539 JP-A-58-191777 JP 2004-307787 A JP-A-55-36237 JP-A-2000-212535 JP 2010-159541 A

However, in order to realize the above antistatic property, the amount of the antistatic component must be increased, and therefore, there is a problem that the physical properties of the adhesive are significantly impaired, and the adhesive strength, tack, cohesive strength, etc. It was difficult to achieve both the physical properties of the pressure-sensitive adhesive and the antistatic property. In addition, since it is an antistatic agent-incorporated adhesive, which has a structure in which an antistatic agent is incorporated in the same molecule as the adhesive, it is difficult to design a composition such as introducing a UV crosslinkable functional group into the adhesive. However, the composition design of the adhesive has been limited.
An object of the present invention is to provide an antistatic agent for an addition-type pressure-sensitive adhesive, which has excellent antistatic properties, does not deteriorate the antistatic performance even in applications in contact with water, and does not contaminate the adherend. It is to provide a possible antistatic agent.

The present inventors have conducted intensive studies in order to solve the above problems, and as a result, have found that a structural unit (a1) derived from a (meth) acrylate having a quaternary ammonium carboxylate group (q) and a (meth) acrylate derived unit. By optimizing the molecular weight and the structure of the copolymer (A) having the structural unit (a2) as an essential structural unit, an antistatic agent-added type having the same or higher antistatic performance as the antistatic agent-incorporated pressure-sensitive adhesive The present invention has been achieved, which is an addition type antistatic agent (X) capable of producing an adhesive.
That is, the present invention is the following six inventions.
(I) A structural unit (a1) derived from a (meth) acrylate salt represented by the following general formula (1) and a structural unit (a2) derived from a (meth) acrylate ester represented by the following general formula (2) An antistatic agent (X) containing a copolymer (A) as an essential constituent unit, wherein the content of a group represented by the following general formula (3) is 50 based on the weight of the copolymer (A). An antistatic agent (X), wherein the weight average molecular weight of the copolymer (A) is from 5,000 to 300,000.

[In the general formula (1), R ^{1 to} R ⁴ are a hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different. R ⁵ is a hydrogen atom or a methyl group. ]
[In the general formula (2), R ⁷ is a hydrogen atom or a methyl group, and R ⁶ is a hydrocarbon group having 4 to 18 carbon atoms. ]
(II) A copolymer (A1) having the structural unit (a2) derived from a (meth) acrylate ester represented by the general formula (2) and the structural unit (a4) derived from (meth) acrylic acid as essential structural units. And a quaternary ammonium carbonate ester represented by the following general formula (4) and / or a quaternary ammonium carbonate carbonate (z1) represented by the following general formula (5) to cause a copolymer ( A method for producing the above antistatic agent (X), comprising a step of producing A).
[In the general formulas (4) and (5), R ^{1 to} R ⁴ are a hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different. In the general formula (4), R ⁸ is a hydrocarbon group having 1 to 20 carbon atoms. ]
(III) An adhesive composition containing the antistatic agent (X) described in (I), the adhesive (B), and the crosslinking agent (D).
(IV) A pressure-sensitive adhesive layer comprising a layer obtained by crosslinking the pressure-sensitive adhesive composition, wherein the layer forms a film having a thickness of 1 to 250 μm.
(V) A pressure-sensitive adhesive film having the pressure-sensitive adhesive layer on at least a part of at least one surface of a substrate.
(VI) A pressure-sensitive adhesive sheet having the pressure-sensitive adhesive layer on at least a part of at least one surface of a substrate.

  The antistatic agent of the present invention can impart an antistatic property to the pressure-sensitive adhesive, is excellent in the antistatic property, and does not lower the antistatic performance even in applications in contact with water, and does not contaminate the adherend. It is useful as an addition-type antistatic agent for pressure-sensitive adhesives.

The antistatic agent (X) of the present invention comprises a structural unit (a1) derived from a (meth) acrylate represented by the above general formula (1) and a (meth) acrylic acid represented by the above general formula (2) An antistatic agent (X) containing a copolymer (A) having a constitutional unit (a2) derived from an ester as an essential constitutional unit, wherein the above formula (3) is based on the weight of the copolymer (A). Wherein the content of the quaternary ammonium carboxylate group (q) is 50 to 80% by weight, and the weight average molecular weight of the copolymer (A) is 5,000 to 300,000. Features.
In the present invention, (meth) acrylate means acrylate and / or methacrylate, and the same description will be used hereinafter.

The weight% of the quaternary ammonium carboxylate group (q) in the copolymer (A) is 50 to 80% by weight, preferably 55 to 75%, more preferably 60 to 70% from the viewpoint of antistatic properties. %.
When the weight% of the quaternary ammonium carboxylate group (q) in the copolymer (A) is less than 50%, sufficient antistatic properties are imparted even when added as an antistatic agent (X). Can not. If it exceeds 80% by weight, contamination on the adherend surface occurs.

  The weight% of the quaternary ammonium carboxylate group (q) in the copolymer (A) depends on the composition of the (meth) acrylate copolymer (A1) and the quaternary ammonium salt ( It can be calculated from the input amount of z).

Further, it can be calculated from the titration by the inverse Epton method.
Specifically, water and a methylene blue indicator are added to the antistatic agent (X) of the present invention or a solution of the antistatic agent (X), and titration is performed using a 0.0035 M sodium lauryl sulfate titration solution. Is the end point. From the titration to the end point of the sodium lauryl sulfate titration solution and the blank test titration, the molar content of quaternary ammonium carboxylate groups per kg (qA) and the weight% of quaternary ammonium carboxylate groups (qB) Is calculated by the following equation.
Formula 1;
(QA) (mol / 1000 g) = [titration in this test (L) −titration in blank test (L)] × concentration of sodium lauryl sulfate titration solution (mol / L) × 40 / sample amount (g)
Formula 2;
(QB) (% by weight) = (qA) × (molecular weight of quaternary ammonium carboxylate group + 44) / 1000

As a result of intensive studies, the present inventors have found that the weight average molecular weight at which the antistatic agent (X) according to the present invention suitably exhibits performance and the acrylic pressure-sensitive adhesive (B2) described later as the pressure-sensitive adhesive (B) are suitably used. It was different from the weight average molecular weight that performed.
Specifically, the weight-average molecular weight of the copolymer (A) in the antistatic agent (X) of the present invention is determined by considering the contamination on the surface of the adherend when added to the adhesive, the antistatic property, and the adhesive strength. From the viewpoint, the weight average molecular weight is from 5,000 to 300,000, preferably from 20,000 to 190,000, more preferably from 20,000 to 140,000, particularly preferably. It is from 30,000 or more to 140,000 or less, most preferably from 50,000 to 100,000.
The molecular weight distribution (Mw / Mn) of the copolymer (A) in the antistatic agent (X) of the present invention is determined from the viewpoints of contamination on the adherend surface when added to the adhesive, antistatic properties and adhesive strength. Therefore, it is preferably 3 or more and 10 or less, more preferably 3 or more and 8 or less.

When the weight average molecular weight of the copolymer (A) in the antistatic agent (X) is less than 5,000, the antistatic performance in applications requiring water resistance is reduced, causing a problem in antistatic properties. This causes a problem in the contamination of the surface of the adherend with the pressure-sensitive adhesive composition.
When the weight average molecular weight of the copolymer (A) exceeds 300,000, the antistatic property is poor and the adhesive strength is reduced.

The weight average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) in the present invention are defined as the weight average molecular weight (Mw), the number average molecular weight (Mn) and the molecular weight distribution measured by gel permeation chromatography analysis using polystyrene as a standard substance. (Mw / Mn).
The measurement conditions of the gel permeation chromatography can be measured, for example, under the following conditions.
Apparatus: "HLC-8120GPC" [manufactured by Tosoh Corporation]
Columns: "Guardcolumn H _XL- H" (1), "TSKgel GMH _XL " (2) [both manufactured by Tosoh Corporation]
Sample solution: 0.25 wt% tetrahydrofuran solution Solution injection volume: 100 μl
Flow rate: 1 ml / min Measurement temperature: 40 ° C
Detector: Refractive index detector Reference material: Standard polystyrene

  The method for producing the copolymer (A) is not limited, but it can be produced by the following method (1) or (2). The production method (1) is preferred.

(1) (meth) acrylic acid (a04) and (meth) acrylic acid ester (a02) represented by the general formula (2) are copolymerized, and the obtained copolymer (A1) and a quaternary ammonium salt ( The copolymer (A) having a quaternary ammonium carboxylate group (q) can be obtained by carrying out z) in the presence or absence of a solvent and by heating and reacting.

The reaction temperature is not particularly limited, but is preferably 50 to 150 ° C. The reaction time is not particularly limited, but is preferably 3 to 50 hours. If necessary, a known curing accelerating catalyst (for example, 2-methylimidazole) may be used as long as there is no adherend contamination.

  The quaternary ammonium salt (z) is a quaternary ammonium carbonate ester represented by the above general formula (4) and / or a quaternary ammonium carbonate carbonate (z1) represented by the above general formula (5). Preferably, it is a quaternary ammonium carbonate ester salt (z11). In this case as well, (A1) and (z1) are similarly reacted in the presence or absence of a solvent, and anion exchange is performed. The copolymer (A) is obtained by appropriately removing carbon dioxide gas by-produced in the reaction from the reaction system.

(2) A (meth) acrylic acid salt (a01) having a quaternary ammonium carboxylate group (q) represented by the above general formula (1) and a (meth) acrylic acid represented by the above general formula (2) This is a method of copolymerizing an acid ester (a02) as an essential constituent unit, and can be carried out by the same production method as in the following (A1).

In the above general formula (1), R _{1 to} R ₄ are a hydrocarbon group having 1 to 20 carbon atoms, and are trimethyldodecyl, trimethyldodecyl, trimethylhexadecyl, trimethyloctadecyl, dimethylethyldodecyl, dimethylethyltetradecyl, dimethyl. Examples include ethylhexadecyl, dimethylethyloctadecyl, dimethyldihexyl, dimethyldidodecyl, tetradecyl, and didecyldimethyl. R _{1 to} R ₄ are preferably a combination of didecyldimethyl.

[Copolymer (A1)]
Here, as the copolymer (A1), (meth) acrylate (a02) and (meth) acrylic acid (a04) represented by the above general formula (2) are copolymerized as essential constituent monomers. Copolymer obtained by the above method.

  As the hydrocarbon group of (a02), an aliphatic hydrocarbon group [n-, iso- or t-butyl group, n-, sec-, iso- or neopentyl group, n-hexyl group, n-octyl group, 2 Alkyl groups such as ethylhexyl group, nonyl group, decyl group, lauryl group, tridecyl group, myristyl group, cetyl group and stearyl group and alkenyl groups such as oleyl group], alicyclic hydrocarbon group (cyclohexyl group and the like), and aromatic Examples include an aliphatic hydrocarbon group (such as a benzyl group and a phenethyl group) and an aromatic hydrocarbon group (such as a phenyl group). Among these, from the viewpoint of the adhesive strength of (A), an alkyl group having 1 to 12 carbon atoms is preferable, and an n-butyl group and a 2-ethylhexyl group are more preferable. As (a1), one type may be used alone, or two or more types may be used in combination.

  In the copolymer (A1), (meth) acrylic acid (a04) and a polymerizable monomer (a05) other than the (meth) acrylate (a02) represented by the general formula (2) may be used as a copolymer component. Good. Examples of (a05) include the following polymerizable monomers (1) to (10). As (a05), one type may be used alone, or two or more types may be used in combination.

(1) Vinyl hydrocarbon (C2-20):
(1-1) Aliphatic vinyl hydrocarbons: alkenes having 2 to 20 carbon atoms [ethylene, propylene, butene, isobutylene, pentene, heptene, diisobutylene, octene, dodecene, octadecene, other α-olefins and the like] Alkadienes having 4 to 20 carbon atoms [butadiene, isoprene, 1,4-pentadiene, 1,5-hexadiene, 1,7-octadiene and the like];
(1-2) Alicyclic vinyl hydrocarbons: mono- or dicycloalkenes and alkadienes [cyclohexene, (di) cyclopentadiene, vinylcyclohexene, ethylidenebicycloheptene, etc.]; terpenes (pinene, limonene, etc.) and the like.
(1-3) Aromatic vinyl hydrocarbon (C8 to C20): Styrene and its hydrocarbyl (alkyl, cycloalkyl, aralkyl and alkenyl) -substituted product (α-methylstyrene, vinyltoluene, 2,4- Dimethylstyrene, ethylstyrene, isopropylstyrene, butylstyrene, phenylstyrene, cyclohexylstyrene, benzylstyrene, crotylbenzene, divinylbenzene, divinyltoluene, divinylxylene and trivinylbenzene, etc.); indene and vinylnaphthalene.

(2) Polymerizable unsaturated carboxylic acids (C4 to C130) and salts thereof:
C4-12 polymerizable unsaturated monocarboxylic acids [crotonic acid, cinnamic acid, vinylbenzoic acid, etc.]; C4-12 polymerizable unsaturated dicarboxylic acids (maleic acid, itaconic acid, fumaric acid, citraconic acid) And mesaconic acid); monohydrocarbyl (1-18 carbon atoms) ester of the above-mentioned polymerizable unsaturated dicarboxylic acid having 4-12 carbon atoms; hydroxyl-containing monomer monoester of succinic acid [8-130 carbon atoms, For example, succinic anhydride ring-opened adduct of 2-hydroxyalkyl (C2-4) (meth) acrylate, anhydride of poly (n = 2-30) oxyalkylene (C2-4) glycol mono (meth) acrylate Anhydrous succinic acid ring-opened adduct and 2-hydroxyalkyl (alkyl group having 2 to 4 carbon atoms) (meth) acrylate adduct of caprolactone (1 to 5 mol) Acid ring-opening adduct]; and the like salts thereof.

(3) Sulfone group-containing vinyl monomers, vinyl sulfate monoesters and salts thereof:
Alkene sulfonic acid having 2 to 14 carbon atoms [vinyl sulfonic acid, (meth) allyl sulfonic acid, methyl vinyl sulfonic acid and the like]; styrene sulfonic acid and its alkyl substituted product having 1 to 24 carbon atoms [α-methyl styrene sulfonic acid and the like] A sulfoalkyl (C1-8) (meth) acrylate or (meth) acrylamide [sulfopropyl (meth) acrylate, 2- (meth) acryloyloxyethanesulfonic acid and 2- (meth) acrylamido-2-methylpropane Sulfonic acid, etc.]; alkyl (3 to 18 carbon atoms) (meth) allyl sulfosuccinate; poly (n = 2 to 30) oxyalkylene (2 to 4 carbon atoms: oxyethylene, oxypropylene, oxybutylene: single, random Sulphate of mono (meth) acrylate Poly (n = 5 to 15) oxypropylene monomethacrylate sulfuric acid ester]; and salts thereof.

(4) Phosphoric acid group-containing vinyl monomers and salts thereof:
(Meth) acryloyloxyalkyl (C1-24) phosphoric acid monoester [2- (meth) acryloyloxyethyl phosphate, phenyl-2-acryloyloxyethyl phosphate, etc.]; (meth) acryloyloxyalkane (C1 to C1) 24) Phosphonic acids [2-acryloyloxyethanephosphonic acid and the like]; and salts thereof.

  Examples of the salts (2) to (4) include salts such as alkali metal salts (such as sodium salts and potassium salts) and alkaline earth metal salts (such as calcium salts and magnesium salts).

(5) Hydroxyl-containing vinyl monomer:
(5-1) Unsaturated carboxylic acid monoester of diol having 2 to 6 carbon atoms [hydroxyalkyl (2 to 6 carbon atoms) (meth) acrylate} hydroxyethyl methacrylate, hydroxyethyl acrylate (hereinafter abbreviated as HEA), hydroxy Propyl (meth) acrylate and hydroxybutyl (meth) acrylate and the like and its lactone (4 to 20 carbon atoms such as butyrolactone, valerolactone, caprolactone and laurolactone) and 1 to 5 mol adduct thereof;
(5-2) poly (n = 2-30) oxyalkylene (C2-4) (meth) acrylate [poly (n = 10) oxyethylene mono (meth) acrylate and the like];
(5-3) poly (n = 2-30) oxyalkylene (2-4 carbon atoms) (meth) allyl ether [poly (n = 10) oxyethylene (meth) allyl ether and the like];
(5-4) unsaturated alcohols having 3 to 8 carbon atoms [(meth) allyl alcohol, crotyl alcohol, 1-buten-3-ol, 2-butene-1,4-diol, etc.];
(5-5) a styrene compound having 8 to 15 carbon atoms [such as hydroxystyrene];
(5-6) C5-C30 alkenyl ether [hydroxyalkyl (C2-C6) alkenyl (C3-C6) ether {2-hydroxyethylpropenyl ether etc.}; sucrose allyl ether etc.];
(5-7) Hydroxyl group-containing (meth) acrylamide having 4 to 10 carbon atoms [N-methylol (meth) acrylamide and the like] and the like.

(6) Nitrogen-containing vinyl monomer:
(6-1) Amide group-containing vinyl monomer (3 to 30 carbon atoms): (meth) acrylamide, N-methyl (meth) acrylamide, N-butyl (meth) acrylamide, diacetone (meth) acrylamide, N, N'-methylene-bis (meth) acrylamide, cinnamamide, N, N-dimethyl (meth) acrylamide, N, N-dibenzyl (meth) acrylamide, methacrylformamide, N-methyl N-vinylacetamide and N-vinylpyrrolidone etc;
(6-2) Nitrile group-containing vinyl monomer (3 to 15 carbon atoms): (meth) acrylonitrile, cyanostyrene, cyanoalkyl (1 to 4 carbon atoms) (meth) acrylate, and the like;
(6-3) Nitro group-containing vinyl monomer (C8-C16): nitrostyrene or the like;
(6-4) Alkyl (C1-4) etherified products of hydroxyl group-containing (meth) acrylamide having 4 to 10 carbon atoms [N-butoxymethyl (meth) acrylamide and the like];
(6-5) Primary or secondary amino group-containing (meth) acrylate having 5 to 15 carbon atoms [aminoalkyl (2 to 6 carbon atoms) (meth) acrylate {aminoethyl (meth) acrylate, etc.}, alkyl (carbon Formulas 1 to 6) aminoalkyl (1 to 6 carbon atoms) (meth) acrylate {t-butylaminoethyl methacrylate and the like};
(6-6) Primary or secondary amino group-containing acrylamide having 5 to 10 carbon atoms [N-aminoalkyl (2 to 6 carbon atoms) (meth) acrylamide {N-aminoethyl (meth) acrylamide, etc.] and alkyl ( C2-C6 aminoalkyl (C1-C6) (meth) acrylamide {t-butylaminoethylacrylamide etc.} etc.].

(7) Epoxy group-containing vinyl monomers: glycidyl (meth) acrylate and the like.
(8) Halogen-containing vinyl monomer:
Vinyl chloride, vinyl bromide, vinylidene chloride, (meth) allyl chloride, chlorostyrene, bromostyrene, dichlorostyrene, chloromethylstyrene, tetrafluorostyrene, chloroprene, fluorinated olefin (2 to 10 carbon atoms, 1 fluorine atom) -20) and fluorinated alkyl (2-10 carbon atoms, 1-20 fluorine atoms) (meth) acrylate.

(9) Vinyl esters:
C2 to C6 unsaturated alcohol [vinyl alcohol, (meth) acrylic alcohol and isopropenyl alcohol, etc.] or an ester of hydroxystyrene with a C1 to C12 mono- or polycarboxylic acid (vinyl acetate, vinyl butyrate, Vinyl propionate, vinyl butyrate, diallyl phthalate, diallyl adipate, isopropenyl acetate, methyl-4-vinyl benzoate, vinyl methoxy acetate, vinyl benzoate, acetoxy styrene, etc.); alkyl (meth) acrylate (alkyl having 1 to 3 carbon atoms or 19-30) [Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, eicosyl (meth) acrylate, etc.]; polyhydric (2-3) alcohol unsaturated carboxylic acid ester [ethyl Glycol di (meth) acrylate, propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate and polyethylene glycol di (meth) acrylate, etc.] or the like.

(10) Other vinyl monomers:
(10-1) Vinyl (thio) ether (methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, 2-ethylhexyl vinyl ether, phenyl vinyl ether, 2-methoxyethyl vinyl ether, methoxybutadiene, 2-butoxyethyl vinyl ether, 3,4- Dihydro 1,2-pyran, 2-butoxy-2'-vinyloxy diethyl ether, 2-ethylmercaptoethyl vinyl ether, phenoxystyrene, divinyl sulfide, p-vinyl diphenyl sulfide, ethyl vinyl sulfide, etc.);
(10-2) Allyl ethers [poly (di-tetra) (meth) allyloxyalkanes (2-6 carbon atoms)] diaryloxyethane, triaryloxyethane, tetraallyloxyethane, tetraallyloxypropane, tetra Allyloxybutane and tetrametaryloxyethane, etc.];
(10-3) Vinyl ketone (vinyl methyl ketone, vinyl ethyl ketone, vinyl phenyl ketone, etc.);
(10-4) vinyl sulfone (vinyl ethyl sulfone, divinyl sulfone, divinyl sulfoxide and the like);
(10-5) Poly (n = 2-30) oxyalkylene (C2-4) unsaturated carboxylic acid diester [poly (n = 10) oxyethylene maleic acid diester and the like] and the like.

  Of (a05), from the viewpoint of antistatic properties, preferred are polymerizable unsaturated monocarboxylic acids having 4 to 12 carbon atoms, and monoalkyl (4 to 12 carbon atoms) of polymerizable unsaturated dicarboxylic acids. 18) Esters are succinic acid-containing monomeric monoesters of succinic acid.

Among the polymerizable monomers (a05), preferred from the viewpoint of not impairing the adhesive performance of the pressure-sensitive adhesive (B) described later are polymerizable unsaturated monocarboxylic acids having 4 to 12 carbon atoms and 4 to 12 carbon atoms. Monohydrocarbyl (C1-18) ester of polymerizable unsaturated dicarboxylic acid, hydroxyl group-containing monomer monoester of succinic acid, amide group-containing vinyl monomer having 3 to 30 carbon atoms, C2 Esters of unsaturated alcohols or hydroxystyrenes having up to 6 carbon atoms and mono- or polycarboxylic acids having 1 to 12 carbon atoms, vinyl hydrocarbons having 2 to 20 carbon atoms, and unsaturated carboxylic acid mono-carboxylic acids having 2 to 6 carbon atoms in diols Esters, more preferably an ester of an unsaturated alcohol having 2 to 6 carbon atoms and a monocarboxylic acid having 1 to 12 carbon atoms, and hydroxyalkyl (2 to 6 carbon atoms) (meth) acrylate; The preferred are ethyl (meth) acrylate, vinyl acetate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate and hydroxybutyl (meth) acrylate.

Among (a05), the composition introduced as the carboxylate group of the quaternary ammonium carboxylate group (q) is not limited, but is preferably a polymerizable unsaturated carboxylic acid (having 3 to 130 carbon atoms), More preferred are polymerizable unsaturated monocarboxylic acids having 3 to 12 carbon atoms, and most preferred is (meth) acrylic acid.
The carboxylate group of the quaternary ammonium carboxylate group (q) has a composition produced from only the carboxylate group of (meth) acrylic acid, so that the weight percentage of the (q) part in (A) can be reduced. It is preferable because it is easy to make it 50% or more.

The weight ratio of the structural unit (a2) derived from the (meth) acrylic ester (a02) and the structural unit (a4) derived from the (meth) acrylic acid, which is the structural unit of the copolymer (A1), is determined by the following. From the viewpoint of the adhesiveness of the pressure-sensitive adhesive composition, the amount of (a2) based on the sum of (a2) and (a4) is preferably 20 to 80% by weight, and more preferably 30 to 70% by weight.
The weight ratio of the structural unit (a5) derived from the polymerizable monomer (a05) is preferably 0 to 30% by weight, more preferably 0 to 20% by weight, based on the total of (a2) and (a4). is there.

The method for producing (A1) is not particularly limited, and a known method can be used. However, a radical polymerization method is preferable, and a solution polymerization method is preferable because the molecular weight can be easily adjusted.
Examples of the solvent used in the solution polymerization include esters [C (hereinafter, carbon number is described as C) 2 to 8, for example, ethyl acetate, butyl acetate], alcohols (C 1 to 8, for example, methanol, ethanol, octanol), Examples thereof include hydrocarbons (C4 to 8, for example, n-butane, cyclohexane, and toluene) and ketones (C3 to 9, for example, methyl ethyl ketone (hereinafter sometimes abbreviated as MEK)).

(Meth) having a quaternary ammonium carboxylate group (q) by heating and reacting (meth) acrylic acid (a04) with a quaternary ammonium salt (z) in the presence or absence of a solvent. An acrylate (a01) is obtained. The reaction temperature is not particularly limited, but is preferably 50 to 100 ° C. The reaction time is not particularly limited, but is preferably 3 to 50 hours.
It is preferable that the quaternary ammonium salt (z) is a quaternary ammonium carbonate ester salt and / or a quaternary ammonium carbonate salt (z1). In this case, (a04) and (z1) are similarly treated. The reaction is carried out in the presence or absence of a solvent, and carbon dioxide gas by-produced in the anion exchange reaction is appropriately removed from the reaction system, whereby (meth) acrylate (a01) is obtained.
[Quaternary ammonium salt (z)]
(Z) in the present invention includes those obtained by quaternizing a tertiary amine (z0) with an alkylating agent.

  Examples of the tertiary amine (z0) include aliphatic amines (C3-20, for example, trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-octylamine, diethyl-1-propylamine, Decylmethylamine, etc.), aromatic ring-containing amines (C6-20, for example, triphenylamine, N-ethyl-N-propylaniline), alicyclic ring-containing amines (C8-20, for example, N, N-dimethylcyclohexylamine), Heterocycle-containing amines (C5-20, for example, N-methylpyrrolidine, N-ethylpyrrolidine, N-methylpiperidine, N-ethylpiperidine, N-methylhexamethyleneimine, N-ethylhexamethyleneimine, N-methylformolin, N, N'-dimethylpiperazine and the like).

  Of these, aliphatic amines are preferable from an industrial viewpoint, and tri-n-butylamine, decyldimethylamine, didecylmethylamine and mixtures thereof are more preferable from the viewpoint of low adherend contamination. It is.

  The tertiary amine (z0) can also be obtained by tertiary primary and secondary amines with an alkylating agent.

The primary and secondary amines include the following.
Examples of the primary amine include aliphatic amines (C1-20, for example, ethylamine, octylamine, dodecaamine), aromatic amines (C6-20, for example, aniline, naphthylamine), and alicyclic amines (C6-20, for example, cyclohexylamine). And mixtures thereof; examples of the secondary amine include aliphatic amines (C2 to 20, for example, dimethylamine and diethylamine), aromatic amines (C7 to 20, for example, N-methylaniline, diphenylamine, and phenylnaphthylamine); Amines (C7-20, such as N-methylcyclohexylamine), heterocyclic amines (C5-20, such as N-methyl-2-furylamine, etc.), and mixtures thereof.

  Examples of the alkylating agent include halogenated hydrocarbons [alkyl halides (C1-8, for example, methyl chloride, ethyl chloride, butyl bromide, methyl iodide), and aromatic ring-containing halides (C6-8, for example, phenyl bromide, benzyl chloride). Etc.], dialkyl carbonate (alkyl group is C3-8, for example, dimethyl carbonate, diethyl carbonate), dialkyl sulfate (C2-8, for example, dimethyl sulfate, diethyl sulfate), and organic lithium compound (C4-8, for example, butyl lithium, Phenyllithium), Grignard reagents (such as those obtained by reacting the above-mentioned halogenated hydrocarbons with magnesium) and the like. Among these, dialkyl carbonate is preferred from the viewpoint of adherend contamination.

    Among the above quaternary ammonium salts (z), those which are preferable from the viewpoint of low contamination of the adherend are quaternary ammonium carbonate salts represented by the following general formula (4) and / or the following general formula (5) ) Is a quaternary ammonium carbonate (z1).

In the general formulas (4) and (5), R ^{1 to} R ⁴ are a hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different. In the general formula (4), R ⁸ is a hydrocarbon group having 1 to 20 carbon atoms.

  (Z1) is obtained by quaternizing the tertiary amine (z0) using the dialkyl carbonate, and the cation constituting (z1) is the same as the cation in the general formula (1).

The antistatic agent (X) of the present invention is characterized by containing a copolymer (A) having a quaternary ammonium carboxylate group (q) as an essential component.
The antistatic agent (X) of the present invention can further contain a medium (C). When the antistatic agent (X) contains the medium (C), the handleability can be improved by lowering the viscosity or changing the state of the antistatic agent (X).

Examples of the medium (C) include water and organic solvents [esters having 2 to 8 carbon atoms (such as ethyl acetate, ethyl propionate and butyl acetate), alcohols having 1 to 8 carbon atoms (such as methanol, ethanol and octanol), and carbon atoms. 6-10 hydrocarbons (such as cyclohexane, toluene and light naphtha) and ketones having 3-9 carbon atoms (such as methyl ethyl ketone and methyl isobutyl ketone). (C) may be used alone or in combination of two or more.
The solvent used in producing the hydrocarbyl (meth) acrylate copolymer (A) can be used as the medium (C). The antistatic agent (X) of the present invention can also be produced by removing the solvent used for producing the hydrocarbyl (meth) acrylate copolymer (A) and adding the medium (C).

The medium (C) can be appropriately selected according to the use of the antistatic agent (X) of the present invention, and impairs the performance of the antistatic agent (X) and the pressure-sensitive adhesive composition (coating performance, pressure-sensitive adhesive properties). It is preferable to select a medium (C) not to be used.
In particular, when poly (2-5) isocyanate (D11) is used as the crosslinking agent (D) described below, a medium (C) having a functional group having an active hydrogen (carboxyl group, hydroxyl group, amino group, hydroxymethyl group, etc.) It is preferable that the amount of the compound (1) is small, and it is more preferable that the medium (C) having a functional group having an active hydrogen (a carboxyl group, a hydroxyl group, an amino group, a hydroxymethyl group, etc.) is not contained.

The antistatic agent (X) of the present invention preferably contains the medium (C) from the viewpoint of handling properties, and when (C) is contained in (X), it is contained in (X). More preferably, the amount of the medium (C) is adjusted so that the amount of (A) is in the range of 10 to 70% by weight.
The copolymer (A) includes a structural unit (a1) derived from a (meth) acrylate (a01) and a structural unit (a2) derived from a (meth) acrylate (a02) represented by the following general formula (2). ) Is an essential constituent unit, but may have a constituent unit (a4) derived from (meth) acrylic acid and a constituent unit (a5) derived from the polymerizable monomer (a05) as other constituent units. Good.
The weight ratio between (a1) and (a2) is preferably from 1: 4 to 4: 1.
The weight ratio of (a4) to the total weight of (a1) and (a2) is preferably 0 to 15% by weight, more preferably 0 to 10% by weight.
The weight ratio of (a5) to the total weight of (a1) and (a2) is preferably 0 to 30% by weight, more preferably 0 to 20% by weight.

The pressure-sensitive adhesive composition of the present invention contains an antistatic agent (X), a pressure-sensitive adhesive (B), and a crosslinking agent (D). Since the crosslinking of the pressure-sensitive adhesive composition proceeds at the same time as the mixing, it is preferable that the pressure-sensitive adhesive composition be applied promptly when applied.
The pressure-sensitive adhesive layer, the pressure-sensitive adhesive film and the pressure-sensitive adhesive sheet of the present invention are obtained by crosslinking a pressure-sensitive adhesive composition containing an antistatic agent (X), a pressure-sensitive adhesive (B) and a cross-linking agent (D) from the viewpoint of improving cohesive strength. To use.

As the pressure-sensitive adhesive (B) in the present invention, pressure-sensitive adhesives used in ordinary pressure-sensitive adhesive sheets can be used, and specifically, a rubber-based pressure-sensitive adhesive (B1), an acrylic-based pressure-sensitive adhesive (B2), and a silicone-based pressure-sensitive adhesive ( B3) and an ethylene-based pressure-sensitive adhesive (B4).
As the polymer constituting (B1), rubber having a weight average molecular weight of 400,000 to 20,000,000 (preferably 500,000 to 2,000,000), for example, natural rubber, polyisoprene rubber, polyisobutylene rubber , Polybutadiene rubber, styrene-butadiene-styrene block copolymer and styrene-isoprene-styrene block copolymer.

As the polymer constituting (B2), a (meth) acrylic polymer having a weight average molecular weight of 400,000 to 2,000,000 (preferably 500,000 to 1,500,000), for example, an acrylic monomer single polymer And copolymers of acrylic monomers with other vinyl monomers.
Examples of the acrylic monomer and other vinyl monomers include the above-mentioned hydrocarbyl (meth) acrylates having 4 to 18 carbon atoms in the hydrocarbyl group (a1), and polymerizable monomers (a2) other than (a1). Can be
The copolymer is produced by a known polymerization method (bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, etc.) using a polymerization initiator [azo polymerization initiator (azobisisobutyronitrile, azobisisovaleronitrile, etc.). ), Peroxide-based polymerization initiators (benzoyl peroxide, di-t-butyl peroxide, lauryl peroxide, and the like).
Coating is performed by imparting a reactive group that is crosslinked by ultraviolet (UV) to the (meth) acrylic polymer after polymerization by a known polymerization method (bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, etc.). It is preferable because crosslinking can be performed with ultraviolet light (UV) at the time and after coating, and thus the adhesion can be adjusted.

  Examples of the polymer constituting (B3) include polydimethylsiloxane and polydiphenylsiloxane having a weight average molecular weight of 10,000 to 1,000,000 (preferably 100,000 to 500,000).

  Examples of the polymer constituting (B4) include ethylene / vinyl acetate copolymer resin (EVA) having a weight average molecular weight of 5,000 to 10,000,000 (preferably 30,000 to 2,000,000) and ethylene. / Ethyl acrylate copolymer resin (EEA). Further, the above copolymerizable vinyl monomer may be copolymerized with ethylene. The ethylene content is usually 30 to 97% by weight, preferably 40 to 95% by weight.

  Examples of the form of the pressure-sensitive adhesive (B) include a solvent type, an emulsion type, an aqueous solution type, a solid type for calendering, a heat melting type, and a liquid curing type.

  The amount ratio (solid content ratio) of the antistatic agent (X) and the adhesive (B) in the adhesive composition of the present invention is (X) :( B) = 1 from the viewpoint of antistatic properties and adhesiveness. : 100 to 50: 100 is preferable, and (X) :( B) = 5: 100 to 40: 100 is more preferable.

  Since the antistatic agent (X) of the present invention is an addition-type antistatic agent (X), it can be easily applied to a rubber-based adhesive (B1), a silicone-based adhesive (B3), and an ethylene-based adhesive (B4). Can be provided with an antistatic property, so that the range of applicable pressure-sensitive adhesive (B) is wider than that of a resin having an antistatic property containing a quaternary ammonium base (for example, Patent Document 5). It is.

  The crosslinking agent (D) is not particularly limited, but is a reactive functional group capable of reacting with a functional group having an active hydrogen (such as a carboxyl group, a hydroxyl group, an amino group, or a hydroxymethyl group) in the adhesive (B). An organic compound (D1) having 2 to 5 groups (at least one functional group selected from the group consisting of isocyanate, epoxy, hydrazide, oxazolinyl and aziridinyl groups) in one molecule, and a valence of 2 to 4 At least one selected from the group consisting of polyvalent metal chelate compounds (D2) is preferred.

The lower limit of the molecular weight per functional group of (D1) is preferably 40, more preferably 60, and the upper limit is preferably from the viewpoint of cohesive strength and adhesive strength of the pressure-sensitive adhesive composition. Mw 20,000, more preferably 10,000, particularly preferably 5,000.
The lower limit of the molecular weight per valence of the polyvalent metal of (D2) is preferably 40, more preferably 50 from the viewpoint of the cohesive strength, adhesive strength and tackiness of the adhesive composition, and is preferably the upper limit from the viewpoint of the cohesive strength and adhesive strength. Is 140, more preferably 130, particularly preferably 110.
(D1) includes poly (2-5) isocyanate (D11), poly (2-5) epoxide (D12), hydrazide (D13), oxazoline compound (D14) and aziridine compound (D15).

  Examples of the polyisocyanate (D11) include C (excluding carbon in the NCO group, the same applies hereinafter) 2 to 18 aliphatic polyisocyanate, C4 to 15 alicyclic polyisocyanate, C6 to 20 aromatic polyisocyanate, C8 And at least one compound selected from the group consisting of araliphatic polyisocyanates (1) to (15) and modified products of these polyisocyanates.

Examples of the aliphatic polyisocyanate (hereinafter abbreviated as PI) include diisocyanate (hereinafter abbreviated as DI) [ethylene DI, tetramethylene DI, hexamethylene DI (HDI), dodecamethylene DI, 2,2,4-trimethylhexamethylene DI, Lysine DI, 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate Etc.], triisocyanate (hereinafter abbreviated as TI) [1,6,11-undecane TI, 1,8-diisocyanate-4-isocyanatomethyloctane, 1,3,6-hexamethylene TI and lysine ester TI (lysine and alkanol Phosgenated product of reaction product with amine), 2- Etc., and the following modified products of the above-mentioned DI, etc.], and so-called isocyanatoethyl-2,6-diisocyanatohexanoate, 2- and / or 3-isocyanatopropyl-2,6-diisocyanatohexanoate. .
Among these, tetramethylene DI and HDI are preferred from the viewpoint of availability and industrial viewpoint.

Examples of the alicyclic PI include DI [isophorone DI (IPDI), dicyclohexylmethane DI (hydrogenated MDI), cyclohexylene DI, methylcyclohexylene DI (hydrogenated TDI), bis (2-isocyanatoethyl) -4-cyclohexene -1,2-dicarboxylate, norbornane DI and the like], TI [bicycloheptane TI and the like], and modified products of the above-mentioned DI and the like.
Among these, IPDI, hydrogenated MDI and hydrogenated TDI are preferable from the viewpoint of availability and industrial viewpoint.

Examples of the aromatic PI include DI [tolylene DI (TDI) [2,4- and 2,6-TDI and mixtures thereof], diphenylmethane DI (MDI) [4,4′- and 2,4′-MDI, A), a mixture of di- and tri- or higher-functional PIs [crude TDI, crude MDI (polymethylene polyphenyl polyisocyanate), etc.], and modified products of the above-mentioned DI, etc. No.
Among these, TDI, MDI and NDI are preferred from the viewpoints of availability and industrial viewpoint.

Examples of the araliphatic PI include DI [xylylene DI (XDI), α, α, α ′, α′-tetramethylxylylene DI (TMXDI), diisocyanatoethylbenzene, etc.], and modified products of the above-mentioned DI. No.
Among these, XDI and TMXDI are preferred from the viewpoint of availability and industrial viewpoint.

  Examples of the modified product of the PI include a compound in which a part of the NCO group of the PI exemplified above is modified to a carbodiimide, uretdione, uretoimine, urea, buret, isocyanurate, and / or urethane group.

Among the above-mentioned modified PIs, examples of the modified urethane group include NCO-terminated urethane prepolymers obtained by reacting an excess amount of the above-mentioned PIs with an active hydrogen compound (pseudo-prepolymer containing free PIs). Including).
Examples of the active hydrogen compound include low molecular weight polyvalent (divalent to tetravalent or higher) alcohols and divalent to trivalent poly (n = 2 to 30) oxyalkylenes (C2 to C4).

As low molecular weight polyhydric (divalent to tetravalent or higher) alcohols, dihydric alcohols [aliphatic alcohols [dihydric [C2 to 20, for example, ethylene glycol, diethylene glycol, propylene glycol, 1,3- and 1 , 4-butanediol, 1,6-hexanediol, 3-methylpentanediol, neopentyl glycol (hereinafter abbreviated as EG, DEG, PG, BD, HG, MPD, NPG), 1,9-nonanediol, , 4-bis (hydroxymethyl) cyclohexane], trivalent [C3-8, for example, glycerin, trimethylolpropane (hereinafter abbreviated as GR and TMP), etc.]]; alicyclic alcohol [C4-20, for example, 1,4 -Dihydroxycyclohexane, 2,2-bis (4,4'-hydroxycyclohexyl) propa An aromatic ring-containing alcohol [C8-15, for example, m- and p-xylylene glycol, 1,4-bis (hydroxyethyl) benzene], etc.] and a polyhydric alcohol having 4 or more valences [C5-10 or And pentaerythritol, α-methylglucoside, sorbitol, xylitol, mannitol, glucose, fructose, sucrose, dipentaerythritol, polyglycerin (polymerization degree 2 to 20) and the like.
Examples of the divalent or trivalent poly (n = 2 to 30) oxyalkylene (C2 to C4) include the above-mentioned low molecular weight polyhydric alcohols and / or polyhydric phenols (C6 to C20, such as catechol, resorcinol, bisphenol A, -S and And polyether polyols obtained by adding an alkylene oxide (C2 to 4, hereinafter abbreviated as AO) to -F).

  The PI exemplified above may be blocked with a blocking agent. Examples of the blocking agent include phenol compounds (C6 to C24, for example, phenol, cresol, xylenol, trimethylphenol, ethylphenol, propylphenol, chlorophenol, nitrophenol, thymol, mono-, di- and tri-α-phenylethylphenol) And an active methylene compound [C4-20, for example, acetoacetate (ethyl acetoacetate, butyl acetoacetate, etc.), malonate diester (diethyl malonate, ethylbutyl malonate, ethylbenzyl malonate, etc.), acetylacetone, Benzimidazole and 1-phenyl-3-methyl-5-pyrazolone]; lactams (C4-12, such as ε-caprolactam, δ-valerolactam, γ-butyrolactam and β-propiolactam) Oxime (C3-12 such as acetoxime, methyl ethyl ketone oxime, cyclohexanone oxime, maldoxime, acetoaldoxime, benzophenone oxime and diethylglyoxime); alcohol (C1-24 such as methanol, ethanol, n-butanol, t- Butyl alcohol, t-amyl alcohol, dimethylethynyl carbinol, dimethyl phenyl carbinol, methyl diphenyl carbinol, triphenyl carbinol, 1-nitro-t-butyl carbinol, 1-chloro-t-butyl carbinol and triphenyl Secondary aromatic amines (C6-20, for example, diphenylamine, o-, m-, p-ditolylamine, N-naphthyltoluidine, N-naphthylxylidine, Α-naphthylamine, phenyl β-naphthylamine, carbazole, 2,2′-dinitrodiphenylamine and 2,2′-dichlorophenylamine); mercapto compounds (C1-18, for example, 2-mercaptobenzothiazole, 2-mercaptothiazoline, dodecylmercaptan) Ethyl 2-mercaptothiazole, 2-mercapto5-chlorobenzothiazole, methylmercaptan, ethylmercaptan, propylmercaptan, butylmercaptan, phenylmercaptan, toluylmercaptan, ethylphenylmercaptan and ethynyldimethylthiocarbinol); imidazole compounds (C3 to 10, for example imidazole and 2-ethylimidazole); acid amides (C3-50, for example acetanilide, acrylamide and the like) Fine dimer acid amides); imide (C4～10, e.g. succinimide, phthalimide, and glutaric acid imide) and bisulfite salts.

  In the NCO-terminated urethane prepolymer, the equivalent ratio of NCO groups in PI to active hydrogen (NCO / active hydrogen equivalent ratio) is usually 1.1 / 1 to 100/1, preferably 2/1 to 80/1, More preferably, it is 3/1 to 60/1. The NCO content (% by weight) in the urethane prepolymer is usually from 3 to 35%.

Examples of the polyepoxide (D12) include glycidyl-type polyepoxide (D121) (epoxy equivalent of 80 to 2,500) and non-glycidyl-type polyepoxide (D122) (epoxy equivalent of 43 to 10,000).
Examples of (D121) include glycidyl ether [glycidyl ether of polyhydric phenol (described above) (such as bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and pyrogallol triglycidyl ether); EG-, PG- and NPG diglycidyl ethers, TMP- and GR triglycidyl ethers, etc., glycidyl ethers of polyether polyols (described above) [polyethylene glycol (hereinafter abbreviated as PEG) (Mw 200 to 2,000), polypropylene glycol ( (Hereinafter abbreviated as PPG) (Mw 200 to 2,000) and diglycidyl ether of AO 1 to 20 mol adduct of bisphenol A]]; glycidyl ester [polycarboxylic acid (n = 2 to 4) Glycidyl esters (diglycidyl esters of adipic acid, phthalic acid and dimer acid, triglycidyl trimellitate, etc.); glycidylamine [primary amines (C2-10, for example, hexamethylenediamine, aniline, toluidine, Glycidylation of xylylenediamine) or poly (n = 2 to 4 or more) amine [N, N-diglycidylaniline, N, N-diglycidyltoluidine, N, N, N ′, N′-tetraglycidyldiamino Diphenylmethane, N, N, N ', N'-tetraglycidylxylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N', N'-tetraglycidylhexamethylenediamine And the like.

  Examples of (D122) include aliphatic polyepoxides [C4 to 20, for example, epoxidized (poly) alkadiene [epoxidized butadiene, epoxidized poly (n = 2 to 4 or more) butadiene, epoxidized oil and fat (epoxidized soybean oil and the like) ) Etc.] and alicyclic polyepoxides (such as limonene dioxide and dicyclopentadiene dioxide).

  Examples of hydrazide (D13) include polycarboxylic acids [C2-15, for example, aliphatic (oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, maleic acid), aromatic (phthalic acid, terephthalic acid, isophthalic acid, Naphthalenedicarboxylic acid and the like)) and alkylene (C2-6) dihydrazide (such as ethylene-1,2- and propylene-1,3-dihydrazide).

  The oxazoline compound (D14) includes C3-10, for example, 2-oxazoline, and 2-alkyl (C1-4) -substituted products thereof, for example, 2-methyl-, 2-ethyl-2-, 2-isopropyl-2- and 2-n-propyl-2-oxazoline is mentioned.

  As the aziridine compound (D15), C10-50, for example, a derivative of poly (n = 2 to 4 or more) amine [1,1 ′-(methylene-di-p-phenylene) bis-3,3-aziridinyl urea , 1,1 ′-(hexamethylene) bis-3,3-aziridinyl urea], poly (2-aziridinyl propionate) of low molecular weight polyhydric alcohol (described above) [ethylene bis- (2-aziridinyl) Lepropionate), trimethylolpropane-tris- (2-aziridinylpropionate), 2,4,6-triaziridinyl-1,3,5-triazine, etc.].

Metal chelate compounds (D2) include polyvalent (2- to 4-valent) metals [Group IIA (Mg, Ca, etc.), Group IIB (Zn, etc.), Group IIIA (Al, etc.), Group IVA (Sn, Pb, etc.) , Transition metals (Ti, Zr, manganese, Fe, Co, Ni, Cu, etc.) chelate compounds (chelates with chelators such as β-diketone, acetylacetone, acetoacetate), for example, aluminum chelate compounds [aluminum acetylacetate] Nart [“Aluminum chelate A (W)” manufactured by Kawaken Fine Chemical Co., Ltd.) and the like]).
When (D2) is added to the pressure-sensitive adhesive (B), the chelating ligand in (D2) comes off, and the polyvalent metal coordinates to the functional group of the pressure-sensitive adhesive (B) to perform crosslinking.

The amount of the cross-linking agent (D) used is represented by the equivalent ratio of the active hydrogen in the pressure-sensitive adhesive (B) to the functional group (D1) reacting with the active hydrogen or the valence of (D2). From the viewpoint of the adhesive residue on the body and the adhesion to the adherend, the equivalent ratio of (B) / [(D1) or (D2)] is preferably 1 / 0.01 to 1/2, more preferably The amount is 1 / 0.02 to 1/1.
In addition, the amount ratio of the pressure-sensitive adhesive (B) to the crosslinking agent (D) in the pressure-sensitive adhesive composition of the present invention is determined by the solid content weight ratio of the pressure-sensitive adhesive (B) and the crosslinking agent (D) from the viewpoint of tackiness. , (B) :( D) = 100: 0.01 to 100: 10, and more preferably (B) :( D) = 100: 0.1 to 100: 5.

  The antistatic agent (X) and the pressure-sensitive adhesive composition of the present invention may contain a tackifying resin (E1), a plasticizer (E2), and a filler (E3), if necessary, as long as the effects of the present invention are not impaired. An additive (E) selected from the group consisting of a pigment (E4), an ultraviolet absorber (E5), an antioxidant (E6), a silane coupling agent (E7), and an antistatic agent (E8) other than (X). At least one of the following may be added. As specific examples of (E1) to (E6), those described in JP-A-2008-7702 can be used.

  Examples of the silane coupling agent (E7) include a silicon compound containing a polymerizable unsaturated group (eg, vinyltrimethoxysilane, vinyltriethoxysilane, methacryloxypropyltrimethoxysilane), and a silicon compound containing an epoxy group [3-glycidoxypropyl]. Trimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, etc.], silicon compound containing amino group [3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxy Silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane and the like], 3-chloropropyltrimethoxysilane and the like, and mixtures thereof.

  Examples of the antistatic agent (E8) include a polyether polyol (E81) described in Patent Document 1, a surfactant (E82) described in Patent Document 2, a metal-based conductive filler (E83) described in Patent Document 3, and carbon black. (E84) and quaternary ammonium salts (E85) having a weight average molecular weight of less than 5000.

As a specific example of (E81), the one described in Patent Document 1 can be used. As a specific example of (E82), the one described in Patent Document 2 can be used. As a specific example of (E83), the one described in Patent Document 3 can be used. As a specific example of (E84), the one described in Patent Document 4 can be used.
However, since (E81) to (E84) may cause bleed-out of the antistatic agent even in a small amount, the amount used is limited, and it is preferable not to use it.

  A specific example of (E85) is a quaternary ammonium salt (E85) represented by the following general formula (6), and the same quaternary ammonium salt (z) as described above can be used.

Write it in the chemical formula file.

(In the general formula (6), R ^{1 to} R ⁴ are a hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different. X ⁻ represents an anion that is a conjugate base.)

Among (E85), preferred from the viewpoint of low adherend contamination, X ⁻ is an anion which is a conjugate base of a super strong acid having a Hammett acidity function (H ₀ ) of less than -11.93.

X ^- is a superacid which is a conjugate acid, 100% acid having a stronger acid strength than sulfate ( "superacid-superbase" Kozo Tanabe, Ryoji Noyori al, Kodansha Scientific published, p1 reference) and, Hammett Has an acidity function (H ₀ ) of less than −11.93 of 100% sulfuric acid, and includes a protic acid and an acid composed of a combination of a protic acid and a Lewis acid.

Specific examples of the super acid of a protic acid, trifluoromethanesulfonic acid _(H 0 = -14.10), pentafluoroethane sulfonic acid _(H 0 = -14.00), and the like.

Examples of the protonic acid used in the combination of the protonic acid and the Lewis acid include hydrogen halide (hydrogen fluoride, hydrogen chloride, hydrogen bromide, and hydrogen iodide), and examples of the Lewis acid include boron trifluoride and pentafluoride. Examples include phosphorus, antimony pentafluoride, arsenic pentafluoride, and taurine pentafluoride.
The combination of a protonic acid and a Lewis acid is optional, but specific examples of the superacid obtained by the combination include tetrafluoroboric acid, hexafluorophosphoric acid, chlorofluoroboric acid, hexafluoroantimonic acid, Arsenic fluoride and taurine hexafluoride are exemplified.

As X ⁻ , a quaternary ammonium salt (E85) represented by the general formula (4) and having a weight average molecular weight of less than 5000 is preferable from the viewpoint of heat resistance, because the acidity function (H ₀ ) of Hammett is −12. A conjugate base of a super strong acid of 00 or less, more preferably trifluoromethanesulfonic acid, pentafluoroethanesulfonic acid, tetrafluoroboric acid, phosphorus hexafluoride, chlorofluoroboric acid, antimony hexafluoride, arsenic hexafluoride Or a conjugate base of taurine hexafluoride, particularly preferred is a conjugate base of trifluoromethanesulfonic acid, tetrafluoroboric acid or hexafluorophosphoric acid, most preferred is a conjugate of trifluoromethanesulfonic acid or tetrafluoroboronic acid Is a base.

  From the viewpoint of stain resistance, the content of (E85) in the antistatic agent (X) is the same as that of the hydrocarbyl (meth) acrylate copolymer (A) and the quaternary ammonium salt having a weight average molecular weight of less than 5000. (A) :( E85) = 100: 0 to 100: 5 is preferable, (A) :( E85) = 100: 0 to 100: 3 is more preferable, and the solid content weight ratio of (E85) is more preferable. : (E85) = 100: 0 to 100: 0.5 is more preferred.

  The pressure-sensitive adhesive composition used for the pressure-sensitive adhesive layer, pressure-sensitive adhesive film and pressure-sensitive adhesive sheet of the present invention comprises the antistatic agent (X), the pressure-sensitive adhesive (B), the cross-linking agent (D), and the additive (E) if necessary. Is preferably mixed by a usual mixing apparatus (mixing tank equipped with a stirrer, static mixer, etc.). (B) and (D) are preferably mixed immediately before being applied to a film or a sheet, and (E) is a step of producing the antistatic agent (X) of the present invention (raw material before production, reactant during production or (Product after production).

Among the film-shaped pressure-sensitive adhesive layer, pressure-sensitive adhesive film and pressure-sensitive adhesive sheet of the present invention, the film-shaped pressure-sensitive adhesive layer is formed by releasing the pressure-sensitive adhesive composition of the present invention using a variety of coating apparatuses such as a release film. Directly apply to at least a part of at least one surface of the substrate having moldability, and heat and dry the solvent or the dispersion medium. Preferably, the reaction between the pressure-sensitive adhesive (B) and the crosslinking agent (D) proceeds, Further, it can be produced by a method of curing and crosslinking.
In addition, the pressure-sensitive adhesive film and the pressure-sensitive adhesive sheet are directly coated with the pressure-sensitive adhesive composition of the present invention on at least a part of at least one surface of the substrate by using various coating apparatuses, and heated to dry the solvent or the dispersion medium. At the same time, preferably, the reaction between the pressure-sensitive adhesive (B) and the cross-linking agent (D) is advanced, followed by curing and cross-linking, or after the pressure-sensitive adhesive composition is similarly applied to a release film or the like, and then dried. The obtained pressure-sensitive adhesive can be manufactured into a film, sheet, or tape form by a method of transferring the pressure-sensitive adhesive to at least one surface of a substrate.

Heating means for curing the pressure-sensitive adhesive composition of the present invention include hot air (60 to 150 ° C.), (near) infrared light, high frequency, and the like.
The curing conditions include, for example, about 3 to 7 days at room temperature or about 12 to 72 hours at 45 ° C.
The thickness of the coating film after drying and curing of the pressure-sensitive adhesive composition is preferably from 1 to 250 μm, more preferably from 1 to 100 μm, from the viewpoint of the adhesive strength of the pressure-sensitive adhesive and the drying and curing properties.

  The coating method is not particularly limited, and a known coating method such as spiral coating, roll coating, slot coat coating, control seam coating, and bead coating can be used. Coating devices include gravure coaters, roll coaters (gravure rolls and reverse rolls, etc.), reverse coaters, doctor blades, bar coaters, comma coaters, fountain die coaters, lip coaters, knife coaters, curtain coaters, beads, spirals, sprays, slots and extruders (Single-screw, twin-screw extruder and kneader-ruder) and the like.

  The pressure-sensitive adhesive film and the pressure-sensitive adhesive sheet of the present invention have a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition of the present invention, and usually include a pressure-sensitive adhesive layer and an adherend.

  Examples of the material of the adherend include glass, various plastics [polyolefin (polyethylene and polypropylene, etc.), polyurethane, polyethylene terephthalate, polyvinyl chloride, rayon, polyamide, etc.], paper (Japanese paper and crepe paper, etc.), metal and wood. Can be Among these adherends, those that are easily charged are desirably provided with antistatic properties by adding or applying various antistatic agents.

  Examples of the shape of the adherend include a film, a sheet, a flat yarn, a plate, a foam, a woven fabric, and a nonwoven fabric.

  The antistatic agent (X) and the pressure-sensitive adhesive composition of the present invention can be used for surface protection of various optical members such as a polarizing plate, a retardation plate, and a light diffusion plate, and a liquid crystal display, an organic EL display, a plasma display, a field emission display, and the like. Surface protection films for the surface protection of various image display devices, dicing tapes, tapes for processing electronic components such as carrier tapes, polarizing plates, retardation plates, optical compensation films, brightness enhancement films, light diffusion films, and more Are used for bonding optical components such as those on which they are laminated, liquid crystal panels, various light sources and diffusion plates, and other components constituting various image display devices such as liquid crystal displays, organic EL displays, plasma displays, and field emission displays. It is suitably used as a pressure-sensitive adhesive used in the above. In addition, it is used for various purposes such as surface protection of stainless steel plates, plastic plates and painted surfaces, packaging (packing and packaging of plastic cases, etc.), masking (glass sealing, architectural curing, etc.), medical treatment (such as plasters) and office use. It is also suitably used for applications.

  Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited thereto. In the following, "parts" indicates parts by weight and "%" indicates% by weight.

[Production of quaternary ammonium carbonate ester (z1)]
Production Example 1
A stirred autoclave was charged with 311 parts of didecylmethylamine, 90 parts of dimethyl carbonate and 64 parts of methanol as a solvent and reacted at a reaction temperature of 110 ° C. for 12 hours. Thereafter, methanol was distilled off under reduced pressure at 50 ° C. 401 parts of didecyldimethylammonium monomethyl carbonate (z1-1) were obtained.

[Production of antistatic agent (X) containing copolymer (A)]
Example 1
250 parts of MEK was charged into a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel, and a nitrogen gas introduction pipe, and the temperature was raised to 80 ° C. Next, 70 parts of n-butyl acrylate, 30 parts of acrylic acid, 50 parts of MEK, and 0.85 part of 2,2′-azobis (2,4-dimethylvaleronitrile) were charged into the dropping funnel to obtain a uniform mixed solution. The dropping funnel was attached to a reaction vessel, and was continuously dropped into the reaction vessel over 4 hours while passing nitrogen gas, thereby performing radical polymerization. After completion of the dropwise addition, the mixture was aged for 1 hour, and then 50.5 parts of a 2,2'-azobis (2-methylbutyronitrile) / MEK (0.5 part / 50 parts) solution was added over 2 hours using a dropping funnel. Radical polymerization was performed by continuous dropping.
Further, after the polymerization was continued at 80 ° C. for 3 hours, 50 parts of MEK was added as a diluting solvent to obtain a solution of a (meth) acrylate copolymer (A1-1) having a carboxylic acid group.
To 100 parts of the solution (A1-1), 30 parts of didecyldimethylammonium monomethyl carbonate (z1-1) was added, and the mixture was reacted at a reaction temperature of 70 ° C. for 4 hours to remove by-produced carbon dioxide. An antistatic agent (X-1) comprising a solution of a (meth) acrylate copolymer (A-1) having a didecyldimethylammonium carboxylate group was obtained. The solid content concentration of (X-1) was 34%, the weight% of the quaternary ammonium carboxylate group (q) in (A-1) was 62%, and the Mw of (A-1) was 90,000. Was.

Examples 2 to 7, Comparative Example 1, and Comparative Example 4
Except that (meth) acrylic acid ester (a02) having 4 to 18 carbon atoms (a02), (meth) acrylic acid (a04), and quaternary ammonium carbonate ester salt (z1-1) are changed to those shown in Table 1. In the same manner as in Example 1, the antistatic agents (X-2) to (X-7) of the present invention comprising a solution of the copolymers (A-2) to (A-7), and a (meth) acrylate copolymer Comparative antistatic agents (X'-1) and (X'-4) comprising solutions of the polymers (A'-1) and (A'-4) were obtained.

Example 8
The (meth) acrylic acid ester (a02), (meth) acrylic acid (a04) and quaternary ammonium carbonate ester (z1-1) having 4 to 18 carbon atoms were changed to those shown in Table 1, and 2 In the same manner as in Example 1 except that 2, part of 2,2'-azobis (2,4-dimethylvaleronitrile) was used, the antistatic agent (X-8) of the present invention comprising a solution of the copolymer (A-8) was used. ) Got.

Example 9
The (meth) acrylic acid ester (a02), (meth) acrylic acid (a04) and quaternary ammonium carbonate ester (z1-1) having 4 to 18 carbon atoms were changed to those shown in Table 1, and 2 In the same manner as in Example 1 except that 0.5 part of 2,2'-azobis (2,4-dimethylvaleronitrile) was used, the antistatic agent (X) of the present invention comprising a solution of the copolymer (A-9) was prepared. -9) was obtained.

[Production of antistatic agent (X ') containing copolymer (A') for comparison]
Comparative Example 2
250 parts of MEK was charged into a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel, and a nitrogen gas introduction pipe, and the temperature was raised to 80 ° C. Next, 40 parts of n-butyl acrylate, 30 parts of 2-ethylhexyl acrylate, 30 parts of acrylic acid, 50 parts of MEK, and 6.55 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) were charged into the dropping funnel and homogeneously charged. A mixture was obtained. The dropping funnel was attached to a reaction vessel, and was continuously dropped into the reaction vessel over 4 hours while passing nitrogen gas, thereby performing radical polymerization. After completion of the dropwise addition, the mixture was aged for 1 hour, and then 53.5 parts of a 2,2′-azobis (2-methylbutyronitrile) / MEK (3.5 parts / 50 parts) solution was added over 4 hours using a dropping funnel. Radical polymerization was performed by continuous dropping.
Further, after continuing the polymerization at 80 ° C. for 3 hours, 50 parts of MEK was added as a diluting solvent to obtain a solution of a (meth) acrylate copolymer (A1′-7) having a carboxylic acid group.
To 100 parts of the solution of (A1′-7), 30 parts of didecyldimethylammonium monomethyl carbonate (A2-1) is added, and the mixture is reacted at a reaction temperature of 70 ° C. for 4 hours to remove by-produced carbon dioxide. Thus, a comparative antistatic agent (X'-7) comprising a solution of a (meth) acrylate copolymer (A'-2) having a didecyldimethylammonium carboxylate group for comparison was obtained. The solid content concentration of (X′-2) is 34%, the weight% of the quaternary ammonium carboxylate group (q) in (A′-2) is 62%, and the Mw of (A′-2) is 4%. Was a thousand.

Comparative Example 3
100 parts of ethyl acetate was charged into a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel, and a nitrogen gas introduction pipe, and the temperature was raised to 80 ° C. Next, 40 parts of n-butyl acrylate, 30 parts of 2-ethylhexyl acrylate, 30 parts of acrylic acid, 50 parts of ethyl acetate, and 0.5 part of 2,2′-azobis (2,4-dimethylvaleronitrile) were added to the dropping funnel. A homogeneous mixed solution was obtained. The dropping funnel was attached to a reaction vessel, and was continuously dropped into the reaction vessel over 4 hours while passing nitrogen gas, thereby performing radical polymerization. After completion of the dropwise addition, the mixture was aged for 1 hour, and then 50.5 parts of a 2,2′-azobis (2-methylbutyronitrile) / ethyl acetate (0.5 part / 50 parts) solution was added for 4 hours using a dropping funnel. The mixture was continuously dropped to cause radical polymerization.
After continuing the polymerization at 80 ° C. for 3 hours, 200 parts of MEK was added as a diluting solvent to obtain a solution of a (meth) acrylate copolymer (A1′-8) having a carboxylic acid group.
To 100 parts of the solution (A1'-8), 30 parts of didecyldimethylammonium monomethyl carbonate (A2-1) is added, and the mixture is reacted at a reaction temperature of 70 ° C. for 4 hours to remove by-produced carbon dioxide. As a result, a comparative antistatic agent (X'-8) comprising a solution of a (meth) acrylate copolymer (A'-3) having a didecyldimethylammonium carboxylate group for comparison was obtained. The solid content concentration of (X′-3) is 34%, the weight% of the quaternary ammonium carboxylate group (q) portion in (A′-3) is 62%, and the Mw of (A′-3) is 35%. It was 10,000.

Comparative Example 5
As a comparative antistatic agent (X'-5), lithium bis (trifluoromethanesulfonyl) imide [manufactured by Tokyo Chemical Industry Co., Ltd.] was used.

[Adjustment of solid concentration of antistatic agent]
By diluting the antistatic agents (X-1) to (X-9) and the antistatic agents (X'-1) to (X'-5) for comparison with the calculated amount of MEK, the solid contents are respectively reduced. Antistatic agents (XX-1) to (XX-9) whose concentration was adjusted to 20% and antistatic agents (XX'-1) to (XX'-5) whose solid content for comparison was adjusted to 20% It was created.

[Production of adhesive (B)]
Production Example 1
50 parts of MEK was charged into a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel, and a nitrogen gas introduction pipe, and the temperature was raised to 80 ° C. Next, 80 parts of n-butyl acrylate, 17 parts of 2-hydroxyethyl acrylate, 3 parts of acrylic acid, 30 parts of MEK, and 0.45 part of 2,2′-azobis (2,4-dimethylvaleronitrile) were charged into the dropping funnel. A homogeneous mixture was obtained. The dropping funnel was attached to a reaction vessel, and was continuously dropped into the reaction vessel over 4 hours while passing nitrogen gas, thereby performing radical polymerization. After completion of dropping, the mixture was aged for 1 hour, and then 20.3 parts of a 2,2′-azobis (2-methylbutyronitrile) / MEK (0.3 part / 20 parts) solution was added over 2 hours using a dropping funnel. Radical polymerization was performed by continuous dropping.
Further, after continuing polymerization at 80 ° C. for 3 hours, 10 parts of 2-methacryloyloxyethyl isocyanate was added, and the reaction was continued at 60 ° C. for 3 hours.
Further, by adding MEK as a diluting solvent, a solution of the pressure-sensitive adhesive (B-1) whose solid content concentration was adjusted to 20.0% was obtained. Mw by GPC of (B-1) was 400,000.

Example 11
20 parts of the antistatic agent (XX-1) whose solid content concentration was adjusted to 20%, 80 parts of (B-1), and N, N, N ', N'-tetraglycidylxylylenediene as a crosslinking agent (D). Two parts of a 10% toluene solution (D-1) of an amine [manufactured by Mitsubishi Gas Chemical Industry Co., Ltd., trade name "TETRAD-X"] was added, and the mixture was uniformly mixed to prepare a mixed solution. This blended liquid is applied to a release polyester film [manufactured by Lintec Co., Ltd., trade name "Supertech SP-PET38"] base material after drying so that the film thickness becomes 30 [mu] m, and further at 100 [deg.] C. for one minute at 60 [deg.] C. Each was dried with hot air at a temperature of 1 ° C. for 1 minute, further cured at 45 ° C. for 3 days, and then peeled from the release polyester film to obtain a pressure-sensitive adhesive layer (a film consisting of a pressure-sensitive adhesive without a base material; the same applies hereinafter).
In the above, "Supertech" was replaced with a polyester film (trade name "Lumirror" type T, manufactured by Toray Industries, Inc.), and the above-mentioned composition was applied on the film so as to have a thickness of 30 μm after drying. In the same manner as described above, a pressure-sensitive adhesive film (a film comprising a substrate and a pressure-sensitive adhesive, hereinafter the same) was obtained. The pressure-sensitive adhesive layer or the pressure-sensitive adhesive film was evaluated according to the following performance evaluation method. Table 2 shows the contents of the obtained samples. Table 2 shows the evaluation results.

Examples 12 to 20, Comparative Examples 11 to 17
The same operation as in Example 11 was carried out except that the antistatic agents (XX-1) and (B-1) were changed to those shown in Table 2, to prepare a pressure-sensitive adhesive layer or a pressure-sensitive adhesive film, and to evaluate each performance. did. Table 2 shows the contents of the obtained samples. Table 2 shows the evaluation results.

(1) Adhesive strength Adhesive film test piece was stuck on a stainless steel plate (SUS304, the same applies hereinafter) so that the stuck area would be 25 mm in width x 100 mm in length. ], And the adhesive strength (unit: N / 25 mm) at normal temperature (23 ° C) was evaluated according to JIS-Z-0237.

(2) Antistatic properties before surface immersion (surface resistivity)
After the pressure-sensitive adhesive layer test piece was allowed to stand at 23 ° C. × 65% RH for 12 hours, the surface resistivity was evaluated by the method described in JIS-K6911.

(3) Antistatic properties after immersion (surface resistivity)
0.1 g of the pressure-sensitive adhesive layer test piece and 100 g of ion-exchanged water were placed in a polypropylene container, and the pressure-sensitive adhesive layer test piece was immersed in ion-exchanged water for 24 hours. After immersion, the pressure-sensitive adhesive layer test piece was taken out of the ion-exchanged water, and allowed to stand at 23 ° C. × 65% RH for 12 hours, and the surface resistivity was evaluated by the method described in JIS-K6911.
In the case of “−” in Comparative Examples 11 and 14, since the result of the antistatic property (surface resistivity) test before immersion was 1 × 10 12 Ω / □ or more, the antistatic property test after immersion was not performed. Means that.
The rate of change of the surface resistivity after immersion was calculated from the following equation and is shown in Table 2.
Calculation formula of change rate of surface resistivity: Change rate of surface resistivity = 100 × (surface resistivity after flooding-surface resistivity before flooding) / surface resistivity before flooding

(4) Contamination on adherend surface
An adhesive film test piece having an area of 50 × 100 mm was stuck on a stainless steel plate and allowed to stand at 60 ° C. × 90% RH for one week. Then, the test piece was peeled off and the surface of the stainless steel plate was contaminated by fogging and adhesive residue. The presence or absence was visually observed and evaluated according to the following criteria.
：: Neither clouding nor glue residue △: Slight clouding or glue residue ×: Significant clouding or glue residue

  From the results in Table 2, it is found that the weight percentage of the quaternary ammonium carboxylate group (q) in (A) is 50% or more, and the weight average molecular weight of (A) is 5,000 to 300,000. The pressure-sensitive adhesive composition produced using the inhibitor (X) has a high adhesive strength, is excellent in antistatic properties, and does not lower its antistatic performance even in applications requiring water resistance, and contaminates the adherend. It turned out that there was nothing.

  The antistatic agent and the pressure-sensitive adhesive composition of the present invention include various optical members such as a polarizing plate, a retardation plate, and a light diffusion plate, a surface protective film such as stainless steel and plastic, a dicing tape, and a tape for processing electronic components such as a carrier tape. And various optical members such as a polarizing plate, a retardation plate, and a light diffusion plate, and various image display devices such as a liquid crystal display, an organic EL display, a plasma display, and a field emission display.

Claims (11)

A structural unit (a1) derived from a (meth) acrylate (a01) represented by the following general formula (1) and a structural unit derived from a (meth) acrylate (a02) represented by the following general formula (2) An antistatic agent (X) containing a copolymer (A) having (a2) as an essential constituent unit, wherein the antistatic agent (X) comprises a group represented by the following general formula (3) based on the weight of the copolymer (A). An antistatic agent (X) having a content of 50 to 80% by weight and a weight average molecular weight of the copolymer (A) of 5,000 to 300,000.
[In the general formula (1), R ^{1 to} R ⁴ are a hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different. R ⁵ is a hydrogen atom or a methyl group. ]
[In the general formula (2), R ⁷ is a hydrogen atom or a methyl group, and R ⁶ is a hydrocarbon group having 4 to 18 carbon atoms. ]
[In the general formula (3), R ^{1 to} R ⁴ are a hydrocarbon group having 1 to 20 carbon atoms, which may be the same or different. ]   The antistatic agent (X) according to claim 1, wherein the weight average molecular weight of the copolymer (A) is 20,000 to 190,000.   The antistatic agent (X) according to claim 1 or 2, wherein the copolymer (A) is a copolymer further comprising a structural unit (a4) derived from (meth) acrylic acid.   An adhesive composition comprising the antistatic agent (X) according to claim 1, an adhesive (B), and a crosslinking agent (D).   The pressure-sensitive adhesive composition according to claim 4, wherein the pressure-sensitive adhesive (B) has a reactive group that is crosslinked by ultraviolet rays.   A pressure-sensitive adhesive layer comprising a layer obtained by crosslinking the pressure-sensitive adhesive composition according to claim 4, wherein the layer forms a film having a thickness of 1 to 250 μm.   An adhesive film having the adhesive layer according to claim 6 on at least a part of at least one surface of a substrate.   An adhesive sheet having the adhesive layer according to claim 6 on at least a part of at least one surface of a substrate. A copolymer (A1) having a structural unit (a2) derived from a (meth) acrylic acid ester represented by the general formula (2) and a structural unit (a4) derived from (meth) acrylic acid as essential structural units, and The copolymer (A) is reacted by reacting with a quaternary ammonium carbonate salt represented by the general formula (4) and / or a quaternary ammonium carbonate salt (z1) represented by the following general formula (5). The method for producing the antistatic agent (X) according to any one of claims 1 to 3, which comprises a step of producing.
[In the general formulas (4) and (5), R ^{1 to} R ⁴ are hydrocarbon groups having 1 to 20 carbon atoms, which may be the same or different. In the general formula (4), R ⁸ is a hydrocarbon group having 1 to 20 carbon atoms. ] A method for producing a pressure-sensitive adhesive film , comprising a step of coating the pressure-sensitive adhesive composition according to claim 4 or 5 on at least a part of at least one surface of a substrate and then crosslinking the substrate. A method for producing a pressure-sensitive adhesive sheet , comprising a step of applying the pressure-sensitive adhesive composition according to claim 4 to at least a part of at least one surface of a substrate and then crosslinking the pressure-sensitive adhesive sheet .