TW201531541A - Adhesive composition containing antistatic agent, and adhesive film - Google Patents

Abstract

Provided in the present invention are an adhesive composition containing an antistatic agent which does not damage the adhesive performance, has excellent antistatic properties, and has excellent re-workability, and an adhesive film using the same. The adhesive composition containing an antistatic agent is characterized by containing a pentafluorobenzene compound which is a compound having pentafluorophenyl group (C6F5 group) as an antistatic agent. The pentafluorobenzene compound is an ionic compound, and the anion is preferred to be one kind selected in an anion group consisting of pentafluorobenzene carboxylic acid anion, penta fluorobenzene sulfonic acid anion, and pentafluoro phenoxy anion.

Description

Adhesive composition containing antistatic agent and adhesive film

The present invention relates to an adhesive composition containing an antistatic agent and an adhesive film. More specifically, the adhesive composition containing a compound having a pentafluorophenyl group (C ₆ F ₅ group) as an antistatic agent (hereinafter referred to as "pentafluorobenzene compound"), and an adhesive film using the same . The present invention relates to an adhesive composition which is excellent in anti-adhesion property, excellent in antistatic property, and excellent in reworkability, and an adhesive film using the same.

In the manufacturing process and assembly steps of precision parts and components such as electronic equipment parts, optical equipment parts, and video display panels, in order to temporarily protect the surfaces of these precision parts and components, the particles and gases from the working environment gas are prevented. The adhesion of contaminants, or the generation of scratches and dents, attaches a surface protection film to the surface of precision parts and components.

For example, the surface protective film used in the step of producing an optical member such as a polarizing plate or a phase difference plate constituting a member of a liquid crystal display is a polyethylene terephthalate (PET) resin film having optical transparency. An adhesive layer is formed on one surface, but the release-treated release film for protecting the adhesive layer is attached to the adhesive layer until it is bonded to the optical member.

In addition, the optical member such as the polarizing plate or the retardation film is subjected to display performance, hue, contrast, and contrast with the liquid crystal display panel in a state in which the surface protective film is bonded. Since the product is inspected for optical evaluation such as mixing, the performance required for the surface protective film is such that no air bubbles or foreign matter adhere to the adhesive layer.

Further, in recent years, when the surface protective film is peeled off from an optical member such as a polarizing plate or a retardation plate, there is a concern that peeling electrification due to static electricity generated when the adhesive layer is peeled off from the adherend affects electrical control of the liquid crystal display. The failure of the circuit requires excellent antistatic properties for the adhesive layer.

Further, when the surface protective film is bonded to an optical member such as a polarizing plate or a retardation plate, the surface protective film is temporarily peeled off and the surface protective film is reattached again for various reasons, and the optical property of the adherend is required at this time. Component peeling (reworkability).

Thus, in recent years, as a required performance for an adhesive layer constituting a surface protective film, from the viewpoint of easiness of use for a surface protective film, adhesion stability over time, excellent antistatic property, and rework are required. Performance, etc.

However, it is possible to satisfy the required performance for the adhesive layer constituting the surface protective film, that is, the respective required properties of the adhesion stability over time, excellent antistatic properties, and reworkability, but at the same time low cost. It is a difficult problem to satisfy the required performance of the adhesive layer of the surface protective film.

For example, the following proposals are known for the stability of adhesion over time.

Acrylic acid obtained by crosslinking a copolymer of an alkyl (meth)acrylate having a carbon number of 7 or less and a copolymerizable compound containing a carboxyl group as a main component and crosslinking the mixture with a crosslinking agent In the adhesive layer, when it adheres for a long period of time, there is a problem that the adhesive moves to the adherend side and adheres, and the adhesion to the adherend increases with time. In order to avoid this problem, it is known to use a copolymer of a (meth)acrylic acid alkyl ester having an alkyl group having a carbon number of 8 to 10 and a copolymerizable compound having an alcoholic hydroxyl group, and to carry out crosslinking with a crosslinking agent. The adhesive layer of the joint treatment (Patent Document 1).

Further, it is proposed to blend a small amount of a copolymer of a (meth)acrylic acid alkyl ester and a carboxyl group-containing copolymerizable compound in the same copolymer as described above, and to provide an adhesive layer which is crosslinked by a crosslinking agent. Wait.

In addition, as a method of imparting antistatic property to the surface protective film, a method of kneading an antistatic agent to a base film is shown as an antistatic agent, and as an antistatic agent, for example, (a) having 4 is disclosed. a cationic antistatic agent of a cationic group such as a quaternary ammonium salt, a pyridinium salt or a first to third amino group; (b) having a sulfonate group, a sulfate group, a phosphate group, a phosphonate An anionic antistatic agent such as an anionic group; (c) an amphoteric antistatic agent such as an amino acid or an amine sulfate; (d) an amino alcohol, a glycerin, a polyethylene glycol, or the like (e) a polymer type antistatic agent obtained by polymerizing a general antistatic agent as described above (Patent Document 2).

Further, in recent years, it has been proposed to contain such an antistatic agent in a base film or to be applied directly to the surface of the base film, but directly to the adhesive layer (Patent Document 3).

Patent Document 3 discloses that (1) contains (a) urethane acrylate, (b) (meth) acrylate having a polyalkylene oxide chain, and (c) a tack imparting single A polymer obtained by radiation polymerization of a polymerizable mixture as a main component, and (2) an ionic compound, an adhesive composition having an antistatic property, and an adhesive sheet using the same. Specifically, as a method for producing the adhesive composition, there is a polycondensation such as urethane acrylate or methoxypolyethylene glycol acrylate containing polyester urethane acrylate. a polymerizable mixture of a (meth) acrylate monomer of an alkylene oxide chain, a tackifying monomer such as hydroxypropyl acrylate, and other comonomers such as isooctyl acrylate as needed, Mixing an ionic compound such as lithium perchlorate, if necessary, adding a photopolymerization initiator, stirring until completely dissolved, and irradiating UV The wire or the like is hardened, whereby an adhesive composition can be obtained.

However, since lithium perchlorate used as an ionic compound has metal corrosiveness, there is a problem that the use place of the obtained adhesive composition having antistatic properties is limited.

In addition, for the reworkability, for example, a curing agent in which an isocyanate compound is blended in an acrylic resin and an adhesive composition in which a specific phthalate oligomer is blended in an amount of 0.0001 to 10 parts by weight based on 100 parts by weight of the acrylic resin is proposed. (Patent Document 4).

In Patent Document 4, an alkyl acrylate having an alkyl group having a carbon number of from 2 to 12 or an alkyl methacrylate having an alkyl group having a carbon number of from 4 to 12 is used as a main monomer component, and may be contained. For example, a monomer component containing a functional group such as a carboxyl group-containing monomer. In general, it is preferable to contain 50% by weight or more of the main monomer, and the content of the functional group-containing monomer component is 0.001 to 50% by weight, preferably 0.001 to 25% by weight, more preferably 0.01%. 25 wt%. The adhesive composition described in Patent Document 4 has a small change in cohesive force and tack strength even under high temperature or high temperature and high humidity, and exhibits an excellent effect on the curved surface adhesive force, and thus has reworkability.

In general, when the adhesive layer is made into a flexible property, adhesive residue tends to occur, and reworkability is liable to lower. That is, it is difficult to peel off at the time of erroneous bonding, and it is difficult to reattach. Therefore, in order to have reworkability, it is necessary to consider crosslinking a monomer having a functional group such as a carboxyl group to the main component, and to form the adhesive layer to a certain hardness.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. SHO 63-225677

[Patent Document 2] Japanese Patent Laid-Open No. Hei 11-070629

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2000-129235

[Patent Document 4] Japanese Patent Laid-Open No. Hei 8-199130

In the prior art, as the required performance for the adhesive layer constituting the surface protective film, although the respective requirements of the adhesion stability, the excellent antistatic property, and the reworkability can be satisfied, respectively, but at the same time, The cost is required to satisfy the required performance of the adhesive layer of the surface protective film, which is a difficult problem.

In view of the above, the present invention has an adhesive composition containing an antistatic agent which is excellent in antistatic property and excellent in reworkability, and an adhesive film using the same, which is excellent in antistatic property.

In order to solve the above problems, the present invention provides an adhesive composition containing an antistatic agent, and the antistatic agent contains a compound having a pentafluorophenyl group (C ₆ F ₅ group), that is, a pentafluorobenzene compound.

Preferably, the pentafluorobenzene compound is an ionic compound, and the anion thereof is one selected from the group consisting of an anion group consisting of a pentafluorobenzenecarboxylic acid anion, a pentafluorobenzenesulfonic acid anion, and a pentafluorophenoxy anion.

Preferably, the adhesive polymer is at least one of (A) a C1 to C14 alkyl (meth) acrylate monomer having a carbon number and (B) a hydroxyl group and/or a carboxyl group. The copolymerization product formed of at least one of the vinyl monomers is contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the copolymer composition, and (C) has a compound selected from the above-mentioned pentafluorobenzene compound. One of the group is an anionic ionic compound as an essential component.

Preferably, the adhesive polymer is at least one of (A) alkyl having a C1 to C14 alkyl (meth) acrylate monomer and (B') having a vinyl copolymerized vinyl group. The antistatic agent is contained in an amount of at least one of the above-mentioned copolymerization composition, and the antistatic agent contains 0.1 to 20 parts by weight of (C) having a selected from the above-mentioned pentafluorobenzene compound group. One of the ionic compounds as an anion is an essential component.

Preferably, the adhesive polymer is a copolymerized composition of at least two kinds of (meth)acrylic acid alkyl ester monomers having a C1 to C14 carbon number of (A) alkyl group, and is copolymerized with respect to the above copolymerization. 100 parts by weight of the composition, the antistatic agent contains 0.1 to 20 parts by weight of (C) an ionic compound having an anion selected from the group of pentafluorobenzene compounds as an essential component.

It is preferable that the surface resistivity of the adhesive layer composed of the above-mentioned adhesive composition is 1.0 × 10 ^{+ 12} Ω / □ or less.

Preferably, the above ionic compound is selected from the group consisting of pyridinium, imidazolium, anthraquinone, anthraquinone, pyrrolidinium, anthracene, ammonium, isouronium, thiouronium, piperidinium, pyrazole. Oh, An ionic compound having a cationic group composed of oxonium as a cationic component.

Further, the present invention provides an adhesive film formed by laminating an adhesive layer formed of the above-described adhesive composition on one surface of a substrate.

Further, the present invention provides a surface protective film using the above adhesive film.

Further, the present invention provides a surface protective film for a polarizing plate using the above adhesive film.

Further, the present invention provides an optical surface protective film using the above adhesive film.

Further, the present invention provides an optical film with an adhesive which is formed by laminating an adhesive layer formed of the above-described adhesive composition on at least one side of the optical film.

Further, the present invention provides the above-mentioned optical film with an adhesive, wherein the optical film is a polarizing plate.

Further, the present invention provides an image display device in which the optical film with an adhesive attached thereto is bonded via the adhesive layer.

According to the present invention, by using an adhesive containing a pentafluorobenzene skeleton and a relatively low-cost antistatic agent, the overall cost of the adhesive can be reduced, and problems such as antistatic properties and reworkability can be improved.

Hereinafter, the present invention will be described based on preferred embodiments.

The adhesive composition of the present invention is characterized in that it has an adhesive polymer as an adhesive main agent and an antistatic agent imparting antistatic properties, and the antistatic agent contains a pentafluorophenyl group (C ₆ F _{5 ).} a compound of the group), that is, a pentafluorobenzene compound.

Thereby, an adhesive composition excellent in antistatic performance and excellent in reworkability and an adhesive film using the same can be obtained.

The adhesive polymer used in the present invention is preferably an acrylic polymer, and particularly, at least one of (A) alkyl groups having a C1 to C14 alkyl (meth) acrylate monomer The copolymer composition of the main component is preferred.

Examples of the (meth)acrylic acid alkyl ester monomer having a C1 to C14 carbon number of the (A) alkyl group include methyl (meth)acrylate, ethyl (meth)acrylate, and (meth)acrylic acid. ester, Butyl (meth)acrylate, isobutyl (meth)acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, ( Isooctyl methacrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, decyl (meth) acrylate, (meth) acrylate Cyclopentyl ester, cyclohexyl (meth)acrylate, and the like. The alkyl group of the alkyl (meth) acrylate monomer may be any of a linear chain, a branched chain, and a cyclic group.

As the adhesive polymer used in the present invention, at least one of (A) an alkyl group having a C1 to C14 alkyl group having a carbon number of C1 to C14 may be used, and other copolymerizable monomers may be used. At least one of the copolymerized compositions. In this case, examples of the other copolymerizable monomer include (B') a copolymerizable vinyl monomer having a vinyl group or (B) a copolymerizable vinyl monomer having a hydroxyl group and/or a carboxyl group.

Examples of the hydroxyl group-containing copolymerizable vinyl monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 3-hydroxypropyl (meth)acrylate. a hydroxyl group-containing (meth) acrylate such as 4-hydroxybutyl acrylate, 6-hydroxyhexyl (meth) acrylate or 8-hydroxyoctyl (meth) acrylate, or N-hydroxy (methyl) a hydroxyl group-containing (meth) acrylamide or the like such as acrylamide, N-methylol (meth) acrylamide or N-hydroxyethyl (meth) acrylamide; preferably selected from At least one or more of these compound groups.

Examples of the carboxyl group-containing copolymerizable vinyl monomer include (meth)acrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, and carboxyethyl (meth)acrylate. The carboxypentyl (meth)acrylate or the like is preferably at least one selected from the group consisting of these compounds.

In addition to the above-mentioned copolymerizable vinyl monomer, an aromatic group-containing (meth) acrylate such as benzyl (meth) acrylate or phenoxyethyl (meth) acrylate is used. Other vinyl monomers such as styrene, acrylamide, acrylonitrile, methyl vinyl ether, ethyl vinyl ether, vinyl acetate, and vinyl chloride may be mentioned.

Further, as the adhesive polymer used in the present invention, copolymerization of at least two kinds of (A) alkyl (meth)acrylic acid alkyl ester monomers having a C1 to C14 carbon number may be used. Composition. In this case, a copolymerization composition can be obtained without using a copolymerizable vinyl monomer other than the (A) alkyl group having a C1 to C14 alkyl (meth) acrylate monomer.

The adhesive composition of the present invention contains at least one or more compounds having a pentafluorophenyl group (C ₆ F ₅ group) (that is, a pentafluorobenzene compound) as an essential component. The pentafluorobenzene compound is preferably contained as an antistatic agent. The general formula of the pentafluorobenzene compound is shown by the following formula (Chemical Formula 1). In the formula, Y represents a partial structure containing a functional group having an antistatic property such as an anionic functional group or a nonionic polyether functional group.

The pentafluorobenzene compound used in the present invention, as the polyether functional group used in the case of nonionicity, may be a polyoxyalkylene group such as a polyethylene oxide group or a polypropylene oxide group. The terminal group of the polyether functional group may, for example, be a hydrogen atom, an alkyl group, a mercapto group or an amine group.

The pentafluorobenzene compound used in the present invention is preferably an ionic compound composed of an anion and a cation, and more preferably the ionic compound has various anions selected from the group consisting of pentafluorophenyl groups (C ₆ F ₅ groups). One of the anion groups of the composition is used as an anion.

Examples of the anion having a pentafluorophenyl group (C ₆ F ₅ group) include a carboxylic acid anion having a C ₆ F ₅ group (an anion containing COO ^- in the above Y), and a sulfonic acid anion having a C ₆ F ₅ group. (an anion containing SO ₃ ^- in the above Y), a phosphonic acid anion having a C ₆ F ₅ group (an anion containing PO ₃ ^2- in the above Y), an alkoxide having a C ₆ F ₅ group or a phenoxy anion (containing the Y-O ^- anion), anionic (PEI) having a C ₆ F ₅ group (the Y-containing N ^- anion), methide anion having C ₆ F ₅ group (the Y-containing C ^- an anion), a borate anion having a C ₆ F ₅ group (an anion containing B ^- in the above Y), and the like.

Specific examples of the anion having a C ₆ F ₅ group are not particularly limited, and examples thereof include C ₆ F ₅ COO ^- , C ₆ F ₅ (CH ₂ ) _n COO ^- , and C ₆ F ₅ (CF ₂ ) _n COO. ^- C ₆ F ₅ O(CH ₂ ) _n COO ^- , C ₆ F ₅ (CH=CH) _n COO ^- , C ₆ F ₅ SO ₃ ^- , C ₆ F ₅ (CH ₂ ) _n SO ₃ ^- , C ₆ F ₅ (CF ₂ ) _n SO ₃ ^- , C ₆ F ₅ O(CH ₂ ) _n SO ₃ ^- , C ₆ F ₅ (CH=CH) _n SO ₃ ^- , C ₆ F ₅ O ^- , C ₆ F ₅ (CH ₂ ) _n O ^- , C ₆ F ₅ (CF ₂ ) _n O ^- , C ₆ F ₅ O(CH ₂ ) _n O ^- , (C ₆ F ₅ ) ₂ CHO ^- , (C ₆ F ₅ ) ₃ CO ^- , C ₆ F ₅ OSO ₃ ^- , C ₆ F ₅ O(CH ₂ ) _n SO ₃ ^- , C ₆ F ₅ O(CF ₂ ) _n SO ₃ ^- , (C ₆ F ₅ CO) ₂ N ^- (C ₆ F ₅ CO) ₃ C ^- , (C ₆ F ₅ SO ₂ ) ₂ N ^- , (C ₆ F ₅ SO ₂ ) ₃ C ^- , (C ₆ F ₅ OSO ₂ ) ₂ N ^- , (C ₆ F ₅ OSO ₂ ) ₃ C ^- , C ₆ F ₅ PO ₃ ^2- , (C ₆ F ₅ ) ₄ B ^- and the like (wherein n is an integer of 1 or more).

Pentafluorophenyl compound used in the present invention, especially pentafluorophenyl containing carboxylate anion selected (above Y is COO ^- anion ^{_{i.e., C 6 F 5 COO -.}} ), Pentafluorobenzenesulfonic acid anion (the Y- An anion of SO ₃ ^- , that is, at least C ₆ F ₅ SO ₃ ^- ), a pentafluorophenoxy anion (the above Y is an anion of O ^- , that is, C ₆ F ₅ O ^- ) One or more kinds of ionic compounds which are anions are preferred.

The antistatic agent is preferably contained in an amount of 0.1 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the copolymer composition of the adhesive polymer used in the present invention. One of the pentafluorobenzene compound groups is an anionic ionic compound.

The above ionic compound is preferably selected from the group consisting of pyridinium, imidazolium, anthraquinone, anthraquinone, pyrrolidinium, anthracene, ammonium, isourea, thiourea, piperidinium, pyrazolium, An ionic compound which is one of a cationic group composed of oxonium or the like as a cationic component.

Examples of the pyridinium cation include 1-hexyl-4-methylpyridinium cation, 1-octyl-4-methylpyridinium cation, 1-butyl-4-methylpyridinium cation, 2-methyl 1,2-dodecylpyridinium cation, 1-methylpyridinium cation, 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-hexylpyridinium cation, 1-octylpyridinium cation , 1-mercaptopyridinium cation, 1-dodecylpyridinium cation, and the like.

Examples of the imidazolium cation include a 1,3-dimethylimidazolium cation, a 1-ethyl-3-methylimidazolium cation, a 1-butyl-3-methylimidazolium cation, and a 1-octyl group. -3-methylimidazolium cation, 1-mercapto-3-methylimidazolium cation, 1-dodecyl-3-methylimidazolium cation, and the like.

Examples of the pyrrolizinium cation include 1-methyl-1-ethylpyrrolidinium cation, 1-methyl-1-butylpyrrolidinium cation, and 1-butyl-1-butylpyrrolidinium. Cation, 1-octyl-1-octylpyrrolidinium cation, 1-butyl-1-octylpyrrolidinium cation, 1-mercapto-1-indolylpyrrolidinium cation, 1-dodecyl -1-dodecylpyrrolidine cations and the like.

Examples of the ammonium cation include a tetrabutylammonium cation, a tetraamylammonium cation, a trioctylmethylammonium cation, a trimethylhexylammonium cation, a trimethylpropylammonium cation, and an N,N-dimethyl group. -N,N-dimercapto ammonium cation, N,N-diallyl-N-hexyl-N-methylammonium cation, and aliphatic ammonium cation such as trimethylethylammonium cation; phenyltrimethyl An aromatic ammonium cation such as an ammonium cation, a dimethylethylphenyl ammonium cation or a diethylmethylphenyl ammonium cation.

Examples of the piperidinium cation include a 1-methyl-1-ethylpiperidinium cation. 1-methyl-1-butylpiperidinium cation, 1-butyl-1-butylpiperidinium cation, 1-octyl-1-octylpiperidinium cation, 1-butyl-1-octyl A piperidine cation or the like.

As The oxonium cation may, for example, be 4-methyl-4-ethyl 鎓 鎓 cation, 4-methyl-4-butyl Porphyrin cation, 4-methyl-4-hexyl 鎓 鎓 cation, 4-octyl-4-octyl 鎓 鎓 cation, 4-butyl-4-octyl Porphyrin cation, 4-mercapto-4-indenyl Lanthanide cation, 4-dodecyl-4-dodecyl A porphyrin cation or the like.

Examples of the phosphonium cation include a tetrabutyl phosphonium cation, a triisobutylmethyl phosphonium cation, a tetrapentylphosphonium cation, and a tetrahexylphosphonium cation.

Examples of the ionic compound having an anion of a pyridinium cation and a pentafluorobenzene compound include 1-hexyl-4-methylpyridinium pentafluorobenzenecarboxylate and 1-hexyl-4-methylpyridinium pentafluorobenzene. Phenoxy salt, 1-hexyl-4-methylpyridinium pentafluorobenzenesulfonate, 1-octyl-4-methylpyridinium pentafluorobenzenecarboxylate, 1-octyl-4-methylpyridine Pentafluorophenoxy phenoxide, 1-octyl-4-methylpyridinium pentafluorobenzene sulfonate, 1-butyl-4-methylpyridinium pentafluorobenzenecarboxylate, 1-butyl-4 -methylpyridinium pentafluorophenoxy salt, 1-butyl-4-methylpyridinium pentafluorobenzenesulfonate, 2-methyl-1-dodecylpyridinium pentafluorobenzenecarboxylate, 2-methyl-1-dodecylpyridinium pentafluorophenoxy salt, 2-methyl-1-dodecylpyridinium pentafluorobenzenesulfonate, 1-butylpyridinium pentafluorobenzenecarboxylate Acid salt, 1-butylpyridinium pentafluorophenoxy salt, 1-butylpyridinium pentafluorobenzenesulfonate, 1-octylpyridinium pentafluorobenzenecarboxylate, 1-octylpyridinium pentafluorobenzene Phenoxy salt, 1-octylpyridinium pentafluorobenzenesulfonate, 1-mercaptopyridinium pentafluorobenzenecarboxylate, 1-mercaptopyridinium pentafluorophenoxy salt, 1-mercaptopyridinium Pentafluorobenzenesulfonate, 1-dodecylpyridinium pentafluorobenzenecarboxylate, 1-dodecylpyridinium pentafluorophenoxy salt, 1-dodecylpyridinium pentafluorobenzenesulfonate Acid salt, 1-octyl-3,5-dimethylpyridinium pentafluorobenzenecarboxylate, 1-octyl-3,5-dimethylpyridinium pentafluorophenoxy salt, 1-octyl-3, 5 dimethylpyridinium pentafluorobenzenesulfonate and the like.

Examples of the ionic compound having an anion of an imidazolium cation and a pentafluorobenzene compound include 1-butyl-3-methylimidazolium pentafluorobenzenecarboxylate and 1-butyl-3-methylimidazolium Fluorophenoxy salt, 1-butyl-3-methylimidazolium pentafluorobenzenesulfonate, 1-octyl-3-methylimidazolium pentafluorobenzenecarboxylate, 1-octyl-3-methyl Isoimidazolium pentafluorophenoxy salt, 1-octyl-3-methylimidazolium pentafluorobenzenesulfonate, 1-mercapto-3-methylimidazolium pentafluorobenzenecarboxylate, 1-mercapto -3-methylimidazolium pentafluorophenoxy salt, 1-mercapto-3-methylimidazolium pentafluorobenzenesulfonate, 1-dodecyl-3-methylimidazolium pentafluorobenzenecarboxylic acid Salt, 1-dodecyl-3-methylimidazolium pentafluorophenoxy salt, 1-dodecyl-3-methylimidazolium pentafluorobenzenesulfonate, and the like.

Examples of the ionic compound having an anion of a pyrrolizinium cation and a pentafluorobenzene compound include 1-butyl-1-butylpyrrolidinium pentafluorobenzenecarboxylate and 1-butyl-1-butylpyrrole. Pyridinium pentafluorophenoxy salt, 1-butyl-1-butylpyrrolidinium pentafluorobenzenesulfonate, 1-octyl-1-octylpyrrolidinium pentafluorobenzenecarboxylate, 1-octyl Alkyl-1-octylpyrrolidinium pentafluorophenoxy salt, 1-octyl-1-octylpyrrolidinium pentafluorobenzenesulfonate, and the like.

The surface resistivity of the adhesive layer composed of the above-mentioned adhesive composition is preferably 1.0 × 10 ^{+ 12} Ω / □ or less. When the surface resistivity is large, the performance of static electricity generated by charging at the time of peeling is poor. Therefore, by making the surface resistivity sufficiently small, the peeling tape generated by the static electricity generated when the adhesive layer is peeled off from the adherend can be reduced. The voltage suppresses the bad influence on the electrical control circuit of the adherend.

The adhesive composition of the present invention is preferably such that the adhesive polymer is crosslinked when the adhesive layer is formed. In order to crosslink the adhesive polymer, the adhesive composition may contain a known crosslinking agent, or may be crosslinked by a photocrosslinking reaction such as ultraviolet rays. Examples of the crosslinking agent include a bifunctional or higher isocyanate compound, a bifunctional or higher epoxy compound, a bifunctional or higher acrylate compound, and a metal chelate compound.

Further, as other components, a known additive such as a decane coupling agent, an antioxidant, a surfactant, a curing accelerator, a plasticizer, a filler, a hardening retarder, a processing aid, an anti-aging agent, or the like can be appropriately formulated. These may be used alone or in combination of two or more.

The adhesive film of the present invention is obtained by laminating an adhesive layer composed of the adhesive composition of the present invention on one surface of a base film. The adhesive film of the present invention can be suitably used in the surface protective film, the surface protective film for a polarizing plate, and the optical surface protective film.

As the base film of the laminated adhesive layer or the release film (spacer) for protecting the adhesive surface, a resin film such as a polyester film or the like can be used.

In the base film, antifouling by a polyfluorene-based, fluorine-based release agent, coating agent, cerium oxide microparticle or the like can be performed on the opposite side to the side of the adhesive layer on which the resin film is formed. Treatment; antistatic treatment by coating or kneading of an antistatic agent.

In the release film, a release treatment is performed on a surface on the side to which the adhesive surface of the pressure-sensitive adhesive layer is adhered by a polyfluorene-based or fluorine-based release agent.

In the case of an optical surface protective film such as a surface protective film for a polarizing plate, the base film and the adhesive layer have excellent transparency.

[Examples]

Hereinafter, the present invention will be specifically described based on examples.

<Preparation of acrylic copolymer> [Example 1]

Nitrogen gas was introduced into a reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, and the air in the reaction apparatus was replaced with nitrogen. Then, 100 parts by weight of 2-ethylhexyl acrylate and 1.5 parts by weight of 6-hydroxyhexyl acrylate were added to the reaction apparatus. And 100 parts of solvent (ethyl acetate). Then, 0.1 part by weight of azobisisobutyronitrile was added dropwise thereto over 2 hours, and the mixture was reacted at 65 ° C for 8 hours as a polymerization initiator to obtain an acrylic copolymer solution 1 of Example 1 having a weight average molecular weight of 500,000.

[Examples 2 to 7 and Comparative Examples 1 to 2]

The acrylic copolymer solutions of Examples 2 to 7 and Comparative Examples 1 and 2 were obtained in the same manner as in the acrylic copolymer solution 1 of Example 1 except that the composition of each monomer was as described in Table 1.

<Manufacture of Adhesive Composition and Surface Protective Film> [Example 1]

For the acrylic copolymer solution 1 produced above (in which the acrylic copolymer was 100 parts by weight), 1.0 part by weight of 1-octylpyridinium pentafluorobenzenecarboxylate was added, and CORONATE HX (hexamethylenediene) was added. 1.5 parts by weight of a trimeric isocyanate of an isocyanate (HDI) compound was stirred and mixed to obtain an adhesive composition of Example 1. After the adhesive composition of Example 1 was applied onto a release film composed of a polyethylene terephthalate (PET) film coated with a polyoxynoxy resin, the solvent was removed by drying at 90 ° C. An adhesive sheet having a thickness of 25 μm of the adhesive layer was obtained.

Then, the adhesive sheet is transferred to the opposite side of the antistatic and antifouling treatment surface of the antistatic and antifouling polyethylene terephthalate (PET) film, and the antistatic and antifouling is obtained. The surface protective film of Example 1 was formed by laminating a treated PET film/adhesive layer/release film (PET film coated with a polyoxyl resin).

[Examples 2 to 7 and Comparative Examples 1 to 2]

A surface protective film of Examples 2 to 7 and Comparative Examples 1 and 2 was obtained in the same manner as in the surface protective film of Example 1 except that the composition of each additive was as described in Table 1.

In Table 1, the compounding ratio of each component is represented by a circle, indicating the total of alkyl acrylate monomers (in the case of using a copolymerizable vinyl monomer, an alkyl acrylate monomer and a copolymerized vinyl group). The total of the monomers is a value of 100 parts by weight of the obtained parts by weight. Further, in Table 2, the compound names of the omitted symbols of the respective components used in Table 1 are shown.

In addition, CORONATE (registered trademark) HX, CORONATE HL, and CORONATE L-45 are trade names of Japan Polyurethane Industrial Co., Ltd., TETRAD (registered trademark)-X is the trade name of Mitsubishi Gas Chemical Co., Ltd., DURANATE (registered trademark) 24A-100 is the trade name of Asahi Kasei Chemicals Co., Ltd.

<Test method and evaluation>

The surface protective films of Examples 1 to 7 and Comparative Examples 1 and 2 were aged for 7 days in an environment of 23° C. and 50% RH, and then the release film (PET film coated with polyoxyxylene resin) was peeled off to expose. The finished product of the adhesive layer was used as a test sample of surface resistivity.

Then, the surface protective film exposed to the adhesive layer is adhered to the surface of the polarizing plate adhered to the liquid crystal cell via the adhesive layer, and left for 1 day, and then subjected to autoclaving at 50 ° C, 5 atm, and 20 minutes. , further placed at room temperature for 12 hours, will This is used as a test sample for adhesion.

<adhesion>

Using the tensile tester, the test sample obtained above was peeled off at a low speed (0.3 m/min) and a high speed (30 m/min) in a 180° direction (a surface protective film of 25 mm width was attached to the surface of the polarizing plate). The peel strength was measured, and the peel strength was used as the adhesive force.

<surface resistivity>

After aging, the release film (PET film coated with the polyoxyl resin) was peeled off before being attached to the polarizing plate, and the surface of the adhesive layer was exposed, and the adhesive was measured using a resistivity meter Hirester UP-HT450 (manufactured by Mitsubishi Chemical Analytech). The surface resistivity of the layer.

The evaluation results are shown in Table 1 above. Further, the surface resistivity is represented by a method in which "m × 10 + n" is defined as "mE + n" (where m is an arbitrary real value and n is a positive integer).

The surface protective film of Examples 1 to 7 had a surface resistivity of 1.0 × 10 ^{+ 12} Ω / □ or less and had an appropriate adhesive force. That is, it is possible to improve problems such as defects such as antistatic property and reworkability.

The surface protective film of Comparative Examples 1 and 2 had a surface resistivity of more than 1.0 × 10 ^{+ 12} Ω / □, and was a surface protective film having an antistatic property. Further, since the surface protective film of Comparative Example 1 has an excessively strong adhesive force, it is a surface protective film which is also problematic in reworkability.

Claims (13)

An adhesive composition comprising an adhesive polymer, a crosslinking agent and an antistatic agent, wherein the adhesive polymer is composed of an acrylic polymer, and the antistatic agent is composed of an anion and a cation. The anion contains one ionic compound selected from the group consisting of pentafluorobenzenecarboxylic acid anion, pentafluorobenzenesulfonic acid anion, and pentafluorophenoxy anion. The adhesive composition according to claim 1, wherein the adhesive polymer is at least one selected from the group consisting of (A) alkyl groups having a C1 to C14 alkyl (meth) acrylate monomer; (B) at least one of the copolymerizable vinyl monomers containing a hydroxyl group and/or a carboxyl group, and the antistatic agent contains 0.1 to 10 parts by weight based on 100 parts by weight of the copolymer composition. (C) the above ionic compound as an essential component. The adhesive composition according to claim 1, wherein the adhesive polymer is at least one selected from the group consisting of (A) alkyl groups having a C1 to C14 alkyl (meth) acrylate monomer; (B') at least one of the copolymerizable vinyl monomers having a vinyl group, and the antistatic agent contains 0.1 to 20 parts by weight based on 100 parts by weight of the copolymer composition. (C) The above ionic compound is an essential component. The adhesive composition according to claim 1, wherein the adhesive polymer is at least two kinds of (meth)acrylic acid alkyl ester monomers having a C1 to C14 carbon number of the (A) alkyl group. In the copolymer composition to be formed, the antistatic agent contains 0.1 to 20 parts by weight of the above-mentioned ionic compound (C) as an essential component, based on 100 parts by weight of the copolymer composition. The adhesive composition according to the first aspect of the invention, wherein the adhesive layer comprising the adhesive composition has a surface resistivity of 1.0 × 10 ^{+ 12} Ω / □ or less. The adhesive composition of claim 1, wherein the ionic compound is selected from the group consisting of pyridinium, imidazolium, ruthenium, osmium, pyrrolizidine, ruthenium, ammonium, isouronium, sulfur Thiouronium, piperidinium, pyrazolium, An ionic compound having a cationic group composed of oxonium as a cationic component. An adhesive film formed by laminating an adhesive layer formed of an adhesive composition according to any one of claims 1 to 6 on one side of a substrate. A surface protective film using the adhesive film of claim 7 of the patent application. A surface protective film for a polarizing plate, which is an adhesive film of claim 7 of the patent application. A surface protective film for optics, which is an adhesive film of claim 7 of the patent application. An optical film with an adhesive layer formed by laminating an adhesive layer formed of the adhesive composition according to any one of claims 1 to 6 on at least one side of the optical film. An optical film with an adhesive attached to the eleventh aspect of the patent application, wherein the optical film is a polarizing plate. An image display device is obtained by laminating an optical film with an adhesive attached to claim 11 in the above-mentioned adhesive layer.