TW201942285A - Surface protection film, optical member, and display device - Google Patents

Abstract

Provided is a surface protection film, wherein curling of the surface protection film attached to a release film can be suppressed while maintaining the antistatic properties thereof, and contamination of an adherend can be prevented. This surface protection film according to the present invention is provided with: a substrate film which is formed of a resin material; an adhesive layer which is formed on one surface of the substrate film from an adhesive composition containing a (meth)acrylic polymer as a base polymer and an ionic compound as an antistatic component; an antistatic layer containing an antistatic component and disposed on the surface on the reverse side of the substrate film from the surface having the adhesive layer; and a release film disposed on the surface on the reverse side of the adhesive layer from the surface having the substrate film, wherein the release treatment surface of the release film does not include a silicone component.

Description

Surface protection film, optical member, and display device

The present invention relates to a surface protection film, an optical member protected by the surface protection film, and a display device.

The surface protection film usually has a configuration in which an adhesive layer is provided on a base film (support). This surface protection film is used for the purpose of being adhered to an adherend (protected body) through the above-mentioned adhesive layer, thereby protecting the adherend from damage or contamination during processing, transportation, and the like. .

As a surface protection film, in order to protect the adhesive layer, it is stored in a state where a release film (release liner, separator) is attached until it is attached to an optical member or a display device as an adherend. In general, a release film contains a polysiloxane component as a release agent and is treated with a polysiloxane system.

In addition, since the surface protective film or optical member contains a plastic material, it has high electrical insulation properties and generates static electricity due to friction or peeling. Therefore, static electricity is also easily generated when the surface protective film is peeled off from an optical member such as a polarizing plate. If a voltage is applied to the liquid crystal in a state where the static electricity remains, there may be alignment loss of the liquid crystal molecules, or the panel may be damaged. The presence of static electricity can also be a factor in attracting dust or reducing workability. For this reason, the surface protection film is subjected to an antistatic treatment, for example, an antistatic function is provided by blending an antistatic component in a base film or an adhesive layer constituting the surface protection film (see Patent Document 1).

On the other hand, although antistatic properties can be obtained by imparting antistatic properties to the adhesive layer, the adhesiveness with the release film becomes insufficient, and the problem arises in that the release film peels off from the adhesive layer during storage. In addition, when an external force is applied to the surface protective film attached to the release film, the interface between the adhesive layer containing the antistatic agent and the release film is liable to shift, thereby causing the surface protection film to warp (curly). ), When an optical member or a display device is bonded to a surface protection film, a problem occurs that is unfavorable.

When polyethylene terephthalate (PET) is used for the base film, an unnecessary surface protection film is peeled from the adherend (for example, an optical member) due to the additives contained in PET. The additive is precipitated on the surface of PET, and the PET oligomer contained in PET is precipitated on the surface of the adhesive layer, thereby causing a bad situation that the adherend in contact with the surface of the adhesive layer produces pollution.
[Prior technical literature]
[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2017-165983

[Problems to be solved by the invention]

Therefore, the present invention is a result of intensive research in view of the above circumstances, and an object thereof is to provide a surface protection film that maintains antistatic properties and suppresses curling of the surface protection film attached to the release film, thereby preventing the adherend. (Such as optical components, etc.) contaminated surface protective film.
[Technical means to solve the problem]

That is, the surface protection film of the present invention is characterized in that it is provided with a substrate film containing a resin material, and one side of the above-mentioned substrate film is composed of a (meth) acrylic polymer as a base polymer and An adhesive layer formed of an adhesive composition of an ionic compound of an electrostatic component, an antistatic layer containing an antistatic component on an opposite side of the surface of the base film having the adhesive layer, and an adhesive layer of the adhesive layer The release film on the opposite side of the surface of the substrate film, and the release treatment surface of the release film does not contain a polysiloxane component.

The surface protection film of the present invention preferably has an antistatic layer containing an antistatic component between the substrate film and the adhesive layer.

The optical member of the present invention is preferably protected by the surface protection film.

It is preferable that the display device of the present invention is protected by the surface protective film.
[Effect of the invention]

The surface protection film of the present invention is maintained as a surface protection film by a base film, an antistatic adhesive layer, an antistatic layer, and further a release film having a release treatment surface containing no polysiloxane component. Antistatic property, and suppress the curling of the surface protective film attached to the release film. By making the release treatment surface of the release film free of the polysiloxane component, the pollution caused by the polysiloxane component can be prevented, thereby obtaining A surface protection film that can prevent contamination of an adherend (such as an optical member) due to components precipitated from a base film, and is useful.

Hereinafter, embodiments of the present invention will be described in detail.

＜ Overall structure of surface protection film ＞
The surface protection film disclosed herein is generally called a form of an adhesive sheet, an adhesive tape, an adhesive mark, an adhesive film, a surface protective sheet, etc., and is particularly preferably used as a touch sensor or glass on a liquid crystal display panel. A surface protective film that protects the surface of an optical member during processing or transportation of optical members such as polarizing plates attached through an adhesive layer. The adhesive layer in the surface protection film is typically formed continuously, but is not limited to this form. For example, the adhesive layer may be an adhesive layer formed in a regular or random pattern such as a dot or a stripe. In addition, the surface protection film disclosed herein may be in a roll shape or a single sheet shape.

A typical configuration example of the surface protective film disclosed here is schematically shown in FIG. 1. The surface protection film 10 includes a base film (for example, a polyester film) 2, an antistatic layer provided on one side thereof, and an adhesive provided on a surface of the base film 2 opposite to the surface in contact with the antistatic layer. The layer 3 is further provided with a release film 4 on the surface of the adhesive layer 3 opposite to the surface in contact with the base film 2. The surface protection film 10 is a release film 4 which is in contact with the adhesive layer 3 and is attached to a touch sensor or a substrate glass in an adherend (as a protection object, a liquid crystal display panel (touch panel)). The surface of an optical member such as a polarizing plate attached via the adhesive layer 3). The surface protective film 10 before use (that is, before being adhered to the adherend) has the following form: The surface of the adhesive layer 3 (the adherent surface to the adherend) becomes a release surface by at least the 3 sides of the adhesive layer ( The release film (separator, release liner) 4 is protected. In addition, in order to improve the peelability, the surface of the release film is often subjected to a polysiloxane treatment. However, if the surface of the adhesive layer is in contact with the polysiloxane treatment surface of the release film, it is easy to cause an offset at the interface, and when an external force is applied to the surface protection film, the surface protection film itself curls, which is not good. Therefore, the release treatment of the release film in the present invention does not perform a polysiloxane treatment (a polysiloxane component is not used).

＜ Substrate film ＞
The surface protection film of the present invention is characterized in that it is provided with a substrate film containing a resin material, an adhesive layer on one side of the substrate film, and an opposite side of the surface of the substrate film having the adhesive layer. The antistatic layer of the antistatic layer and the release film on the opposite side of the surface of the adhesive layer having the substrate film. In the technology disclosed herein, the resin material constituting the base film can be used without any particular restrictions, for example, transparency, mechanical strength, thermal stability, water resistance, isotropy, flexibility, and dimensional stability are preferably used. Those with excellent properties. In particular, by making the base film flexible, the adhesive composition can be applied by a roll coater or the like, and can be wound into a roll shape, which is useful.

As the resin material constituting the substrate film, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate, and the like can be preferably used. Polyester polymers; cellulose polymers such as diacetyl cellulose and triethyl cellulose; polycarbonate polymers; acrylic polymers such as polymethyl methacrylate as the main resin component (resin component The main component is typically a plastic film of a resin material which accounts for 50% by weight or more) of the above-mentioned substrate film. Other examples of the resin material include styrene-based polymers such as polystyrene and acrylonitrile-styrene copolymers; polyethylene, polypropylene, polyolefins having a cyclic or norbornene structure, and ethylene-propylene Copolymers such as olefin-based polymers; vinyl chloride-based polymers; polyamide-based polymers such as nylon 6, nylon 6,6, and aromatic polyamides are resin materials. As further examples of the resin material, fluorene-based polymers, fluorene-based polymers, polyether fluorene-based polymers, polyetheretherketone-based polymers, polyphenylene sulfide-based polymers, and vinyl alcohol Based polymers, vinylidene chloride based polymers, vinyl butyral based polymers, aryl ester based polymers, polyoxymethylene based polymers, epoxy based polymers, and the like. It may also be a substrate film containing a blend of two or more of the above polymers.

As the substrate film, a plastic film containing a transparent thermoplastic resin material can be preferably used. More preferably, a polyester film is used among the plastic films. Here, the term "polyester film" refers to a resin mainly composed of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate, and the like, which has an ester bond as a basic component. The polymer material of the skeleton (polyester resin) is the main resin component. The polyester film has preferable characteristics as a base film of a surface protection film, such as excellent optical characteristics or dimensional stability. Among them, it is particularly preferable that the base film contains polyethylene terephthalate and / or polyethylene naphthalate.

Various additives such as an antioxidant, an ultraviolet absorber, a plasticizer, and a colorant (pigment, dye, etc.) can be blended in the resin material constituting the substrate film as necessary. A known or customary method such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, acid treatment, alkali treatment, coating of a primer and the like can be applied to one surface (the surface on the side where the antistatic layer is provided) of the substrate film. Of surface treatment. Such a surface treatment may be, for example, a treatment for improving the adhesion between the substrate film and the antistatic layer. Further, a surface treatment such as introducing a polar group such as a hydroxyl group on the surface of the base film can be preferably used.

The surface protective film of the present invention has an antistatic function by having an antistatic layer in contact with the substrate film. Further, as the substrate film, a plastic film that is subjected to an antistatic treatment can also be used. By using the above-mentioned base film, it is preferable to suppress the charging of the surface protective film itself at the time of peeling. In addition, by making the base film a plastic film and performing an antistatic treatment on the plastic film, it is possible to reduce the electrostatic charge of the surface protection film itself and have excellent antistatic ability to the adherend. In addition, the method for imparting the antistatic function is not particularly limited, and conventionally known methods can be used, and examples thereof include application of an antistatic resin containing an antistatic agent and a resin component, or a conductive polymer, and conductivity. A method of a conductive resin of a substance, a method of vapor-depositing or plating a conductive substance, and a method of kneading an antistatic agent.

The thickness of the substrate film is usually 5 to 200 μm, and preferably about 10 to 100 μm. If the thickness of the substrate film is within the above range, it is preferable because it has excellent adhesion properties to the adherend and peeling workability from the adherend.

＜ Antistatic layer ＞
The surface protection film of the present invention is characterized in that it is provided with the base film, the adhesive layer, an antistatic layer containing an antistatic component on the opposite side of the surface of the base film having the adhesive layer, and A release film on the opposite side of the adhesive layer from the surface having the substrate film. Further, it is preferable to further include an antistatic layer containing an antistatic component between the base film and the adhesive layer. By providing the surface protection film with an antistatic layer, the surface protection film has excellent antistatic properties, or has excellent contamination resistance (low contamination) when it is peeled off after being attached to an adherend, and furthermore, it is applied to the base film and adhesion. When an antistatic layer is provided between the agent layers, the peeling antistatic property or the anti-pollution property (low-pollution property) becomes more excellent, which becomes a preferable aspect. When the antistatic layer is provided on both sides of the base film, the antistatic agent composition constituting the antistatic layer may be the same composition or different.

＜ Conductive polymer ＞
The antistatic layer can be formed by an antistatic agent composition containing an antistatic component. The antistatic component is not particularly limited, and examples thereof include a conductive polymer. As the conductive polymer component, a water-soluble conductive polymer and / or a water-dispersible conductive polymer is preferably used. By using the above-mentioned conductive polymer, the peeling antistatic property by the antistatic layer can be satisfied. The above-mentioned conductive polymer is "water-soluble" or "water-dispersible". However, by using the following cross-linking agent (for example, a melamine-based or isocyanate-based cross-linking agent), the conductive polymer can be fixed in the antistatic layer and can be improved. Water resistance. By using the above-mentioned water-soluble conductive polymer and / or water-dispersible conductive polymer, the surface resistance value of the antistatic layer can be suppressed to a low level, and the antistatic property of the surface protective film can be further improved. Become better.

The water-soluble conductive polymer can be used without particular limitation, and examples thereof include polyaniline sulfonic acid, poly (isobenzothiophene diyl-sulfonate) compound, and (meth) acrylic acid containing a quaternary ammonium salt. Ester-based polymer. The water-dispersible conductive polymer can be used without particular limitation, and examples thereof include polythiophenes and polyanilines doped with polyanions. Among them, polyaniline sulfonic acid is preferably used as the water-soluble conductive polymer, and polythiophenes doped with polyanions are preferably used as the water-dispersible conductive polymer.

Examples of polythiophenes that can be used as the water-dispersible conductive polymer include polythiophene, poly (3-methylthiophene), poly (3-ethylthiophene), and poly (3-propylthiophene). , Poly (3-butylthiophene), poly (3-hexylthiophene), poly (3-heptylthiophene), poly (3-octylthiophene), poly (3-decylthiophene), poly (3-tenylthiophene) Dialkylthiophene), poly (3-octadecylthiophene), poly (3-bromothiophene), poly (3-chlorothiophene), poly (3-iodothiophene), poly (3-cyanothiophene), Poly (3-phenylthiophene), poly (3,4-dimethylthiophene), poly (3,4-dibutylthiophene), poly (3-hydroxythiophene), poly (3-methoxythiophene) , Poly (3-ethoxythiophene), poly (3-butoxythiophene), poly (3-hexyloxythiophene), poly (3-heptyloxythiophene), poly (3-octyloxythiophene) , Poly (3-decyloxythiophene), poly (3-dodecyloxythiophene), poly (3-octadecyloxythiophene), poly (3,4-dihydroxythiophene), poly (3, 4-dimethoxythiophene), poly (3,4-diethoxythiophene), poly (3,4-dipropoxythiophene), poly (3,4-dibutoxythiophene), poly ( 3,4-dihexyloxythiophene), poly (3,4-diheptyloxythiophene), poly (3,4-dioctyloxythiophene), poly (3,4-didecyloxy) Thiophene), poly (3,4-di-dodecyloxythiophene), poly (3,4-ethylenedioxythiophene), poly (3,4-propanedioxythiophene), poly (3,4 -Butadioxythiophene), poly (3-methyl-4-methoxythiophene), poly (3-methyl-4-ethoxythiophene), poly (3-carboxythiophene), poly (3- Methyl-4-carboxythiophene), poly (3-methyl-4-carboxyethylthiophene), poly (3-methyl-4-carboxybutylthiophene). These can be used alone or in combination of two or more. Among these, poly (3,4-ethylenedioxythiophene) (PEDOT) is preferred from the viewpoint of conductivity.

As the polythiophenes, the polymerization degree is preferably 2 to 1,000, and more preferably 5 to 100. If it is in the said range, since it is excellent in electroconductivity, it is preferable.

The polyanionic polymer having a structural unit having an anionic group functions as a dopant to the polythiophene. Examples of the polyanions include polystyrenesulfonic acid, polyvinylsulfonic acid, polyallylsulfonic acid, polypropylenesulfonic acid, polymethacrylic acid, and poly (2-acrylamido-2 -Methylpropanesulfonic acid), polyisoprenesulfonic acid, polyethylsulfonate, poly (4-sulfobutylmethacrylate), polymethallyloxybenzenesulfonic acid, polyvinyl Carboxylic acid, polystyrene carboxylic acid, polyallyl carboxylic acid, polypropylene carboxylic acid, polymethacrylic acid, poly (2-acrylamide-2-methylpropanecarboxylic acid), polyisoprene Carboxylic acid, polyacrylic acid, sulfonated polyphenylacetylene, etc. These may be homopolymers or copolymers of two or more. Among them, polystyrenesulfonic acid (PSS) is preferred from the viewpoint of improving the conductivity and dispersibility of polythiophenes.

The weight-average molecular weight (Mw) of the polyanion is preferably 10 to 1 million, and more preferably 20 to 500,000. If it is in the said range, since it is excellent in doping and dispersibility to polythiophenes, it is preferable.

As the antistatic layer, for example, poly (3,4-ethylenedioxythiophene) (PEDOT) as the polythiophene and polystyrene sulfonic acid (as a polyanion doped with the polythiophene) can be used. In the case of PSS), PEDOT interacts with PSS and exists at a very close distance. As a result, the electrons of PEDOT are taken away by PSS, which can make the antistatic layer exhibit conductivity and become a better state.

Examples of commercially available products of polythiophenes doped with the polyanions include, for example, poly (3,4-ethylenedioxythiophene) / polystyrenesulfonic acid (PEDOT / PSS) manufactured by BAYER Corporation. "Bytron P", "Seplegyda" by Shin-Etsu Polymer, "VERAZOL" by Soken Chemical Co., Ltd., etc.

The polyaniline sulfonic acid that can be used as the water-soluble conductive polymer component is preferably a polystyrene-equivalent weight average molecular weight (Mw) of 5 × 10 ⁵ or less, more preferably 3 × 10 ⁵ or less. The weight average molecular weight of these conductive polymers is usually preferably 1 × 10 ³ or more, and more preferably 5 × 10 ³ or more.

As a commercially available product of the said polyaniline sulfonic acid, the brand name "aquaPASS" manufactured by Mitsubishi Rayon Co., Ltd., etc. can be illustrated.

The antistatic layer disclosed herein may contain, in addition to the above-mentioned conductive polymer component, one or two or more other antistatic components (organic conductive materials other than conductive polymers, inorganic conductive materials, and antistatic materials). Agents, etc.). Furthermore, as a preferred aspect, the antistatic layer does not substantially contain antistatic components other than the conductive polymer, that is, the antistatic component contained in the antistatic layer substantially includes only the conductive polymerization. The state of things can be better implemented.

Examples of the organic conductive substance include a quaternary ammonium salt, a pyridinium salt, a cationic antistatic agent having a cationic functional group such as a primary amine group, a secondary amine group, and a tertiary amine group; a sulfonate or sulfuric acid Anionic antistatic agents with anionic functional groups such as ester salts, phosphonates, and phosphate ester salts; zwitterionic antibodies such as alkyl betaine and its derivatives, imidazoline and its derivatives, and alanine and its derivatives Electrostatic agents; non-ionic antistatic agents such as amino alcohols and their derivatives, glycerol and its derivatives, polyethylene glycol and its derivatives; will have the above-mentioned cationic, anionic, and zwitterionic ionic conductive groups (E.g., quaternary ammonium salt) monomers that are obtained by polymerizing or copolymerizing ionic conductive polymers; conductive polymers such as polythiophene, polyaniline, polypyrrole, polyethylenimine, and allylamine polymers Thing. Such antistatic agents may be used singly or in combination of two or more.

Examples of the inorganic conductive substance include tin oxide, antimony oxide, indium oxide, cadmium oxide, titanium oxide, zinc oxide, indium, tin, antimony, gold, silver, copper, aluminum, nickel, chromium, titanium, iron, Cobalt, copper iodide, ITO (indium oxide / tin oxide), ATO (antimony oxide / tin oxide), etc. Such inorganic conductive materials may be used singly or in combination of two or more kinds.

Examples of the antistatic agent include a cationic antistatic agent, an anionic antistatic agent, a zwitterionic antistatic agent, a nonionic antistatic agent, and conductive ions having the above cationic, anionic, and zwitterionic types. An ion-conductive polymer obtained by polymerizing or copolymerizing a monomer having a basic group.

＜ Adhesives ＞
The antistatic layer may be formed of an antistatic agent composition containing an antistatic component, and preferably further contains a polyester resin as an adhesive. The polyester resin is preferably a resin material containing polyester as a main component (typically, a component that accounts for more than 50% by weight, preferably 75% by weight or more, such as 90% by weight or more). The polyester is typically preferably a polycarboxylic acid (typically, a dicarboxylic acid) having two or more carboxyl groups selected from one molecule, and a derivative thereof (anhydride, esterified product of the polycarboxylic acid, One or two or more compounds (polycarboxylic acid components) and one or two polyhydric alcohols (typically diols) having two or more hydroxyl groups in one molecule A structure obtained by condensing the above compound (polyol component).

Examples of compounds that can be used as the polycarboxylic acid component include oxalic acid, malonic acid, difluoromalonic acid, alkylmalonic acid, succinic acid, tetrafluorosuccinic acid, alkylsuccinic acid, (± )-Malic acid, meso-tartaric acid, itaconic acid, maleic acid, methyl maleic acid, fumaric acid, methyl fumaric acid, acetylene dicarboxylic acid, glutaric acid , Hexafluoroglutaric acid, methylglutaric acid, glutaric acid, adipic acid, dithioadipate, methyladipate, dimethyladipate, tetramethyladipate, Methyl adipic acid, adipic acid, galactic acid, pimelic acid, suberic acid, perfluorosuberic acid, 3,3,6,6-tetramethyl suberic acid, azelaic acid, Aliphatic dicarboxylic acids such as sebacic acid, perfluorosebacic acid, tridecane dicarboxylic acid, dodecyl dicarboxylic acid, tridecyl dicarboxylic acid, tetradecyl dicarboxylic acid; cycloalkyl di Carboxylic acids (e.g. 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid), 1,4- (2-norene) dicarboxylic acid, 5-norene-2,3- Alicyclic dicarboxylic acids such as dicarboxylic acid (bicycloheptene dicarboxylic acid), adamantane dicarboxylic acid, spiroheptane dicarboxylic acid; phthalic acid , Isophthalic acid, dithioisophthalic acid, methyl isophthalic acid, dimethyl isophthalic acid, chloroisophthalic acid, dichloroisophthalic acid, terephthalic acid, methyl para Phthalic acid, dimethyl terephthalic acid, chloroterephthalic acid, bromoterephthalic acid, naphthalenedicarboxylic acid, oxofluorenedicarboxylic acid, anthracenedicarboxylic acid, biphenyldicarboxylic acid, and diphenylene Dicarboxylic acid, dimethyl diphenylene dicarboxylic acid, 4,4 ''-p-phenylene terephthalic acid, 4,4 ''-terephthalic acid, bibenzyl dicarboxylic acid, azo Phthalic acid, homophthalic acid, phenylenediacetic acid, phenylenedipropionic acid, naphthalenedicarboxylic acid, naphthalenedipropionic acid, biphenyldiacetic acid, biphenyldipropionic acid, 3,3'- [4,4 '-(methylenebis-p-biphenyl) dipropionic acid, 4,4'-bibenzyl diacetic acid, 3,3' (4,4'-bibenzyl) dipropionic acid, oxo Aromatic dicarboxylic acids such as di-p-phenylene diacetic acid; anhydrides of any of the above-mentioned polycarboxylic acids; esters of any of the above-mentioned polycarboxylic acids (such as alkyl esters; may be mono-esters, diesters, etc.); The phosphonium halide (for example, dicarboxyphosphonium chloride) and the like corresponding to any of the above polycarboxylic acids.

Preferable examples of the compound that can be used as the polycarboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid, and anhydrides thereof; adipic acid, and sebacic acid. Aliphatic dicarboxylic acids and their anhydrides, such as azelaic acid, succinic acid, fumaric acid, maleic acid, dicycloheptenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, and the above-mentioned dicarboxylic acids Lower alkyl esters of acids (for example, esters with monoalcohols having 1 to 3 carbon atoms) and the like.

On the other hand, examples of the compound usable as the polyol component include ethylene glycol, propylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,3-butanediol, and 1,4- Butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 3-methylpentanediol, diethylene glycol, 1,4-cyclohexanedimethanol, 3- Methyl-1,5-pentanediol, 2-methyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3- Diols such as propylene glycol, benzyl alcohol, hydrogenated bisphenol A, and bisphenol A. As another example, an alkylene oxide adduct (for example, an ethylene oxide adduct, a propylene oxide adduct, etc.) of these compounds is mentioned.

The molecular weight of the polyester resin may be, for example, about 5 × 10 ³ to 1.5 × 10 ⁵ as a weight average molecular weight (Mw) in terms of standard polystyrene measured by gel permeation chromatography (GPC). It is preferably about 1 × 10 ⁴ to 6 × 10 ⁴ ). The glass transition temperature (Tg) of the polyester resin may be, for example, 0 to 120 ° C (preferably 10 to 80 ° C).

As the polyester resin, a commercially available product name "VYLONAL" manufactured by Toyobo Co., Ltd. can be used.

The above-mentioned antistatic layer may not substantially damage the performance of the surface protective film disclosed herein (such as antistatic properties), and further contains a resin other than a polyester resin (for example, selected from acrylic resins, acrylic urethanes). Resin, acrylic styrene resin, acrylic polysiloxane resin, polysiloxane resin, polysilazane resin, polyurethane resin, fluorine resin, polyvinyl alcohol resin, polyolefin resin, etc. The above resins) are used as a binder. In addition, as a reason for using a polyester resin as an adhesive, compared with resins other than polyester resins (for example, the above-mentioned acrylic resins or polyvinyl alcohol resins), the surface free energy is smaller, so even if it is not Additives such as lubricants can also suppress shrinkage and the like when an antistatic agent composition is applied to a base film for film formation. In addition, as a preferable aspect of the technology disclosed herein, the adhesive of the antistatic layer includes only a polyester resin. For example, an antistatic layer in which the proportion of the polyester resin in the adhesive is 98 to 100% by weight is preferred. The proportion of the adhesive in the entire antistatic layer may be, for example, 50 to 95% by weight, and generally suitable is 60 to 90% by weight.

The amount of the conductive polymer used is preferably 10 to 200 parts by weight, more preferably 25 to 150 parts by weight, and still more preferably 40 to 120 parts by weight, with respect to 100 parts by weight of the adhesive. If the amount of the conductive polymer used is too small, the antistatic effect may become small. If the amount of the conductive polymer used is too large, the adhesion of the antistatic layer to the base film may decrease or the transparency may decrease. , Poor.

As a method for forming the above-mentioned antistatic layer, a method for coating, drying (or curing) a coating material (antistatic agent composition) for forming an antistatic layer on one or both sides of a base film may be adopted as The conductive polymer component used for the preparation of the coating material may contain the above-mentioned water-soluble conductive polymer and / or water-dispersible conductive polymer, and the polyester resin as the above-mentioned adhesive, and the above-mentioned may be preferably used. Those in which the conductive polymer is dissolved and dispersed in water (conductive polymer aqueous solution or conductive polymer dispersion). The conductive polymer aqueous solution or aqueous dispersion can be dissolved and dispersed, for example, by dissolving a conductive polymer having a hydrophilic functional group (which can be synthesized by a method such as copolymerizing a monomer having a hydrophilic functional group in a molecule). Prepared in water. Examples of the hydrophilic functional group include a sulfo group, an amine group, an amido group, an imino group, a hydroxyl group, a mercapto group, a hydrazine group, a carboxyl group, a quaternary ammonium group, a sulfate group (-O-SO ₃ H), Phosphate group (for example, -O-PO (OH) ₂ ) and the like. The hydrophilic functional group can form a salt.

＜ crosslinking agent ＞
As the antistatic layer, a melamine-based, isocyanate-based, or epoxy-based cross-linking agent used in cross-linking of ordinary resins can be appropriately selected and used as the cross-linking agent. As a preferred aspect, at least a melamine-based crosslinking agent or an isocyanate-based crosslinking agent is used in the above-mentioned crosslinking agent. By using the above-mentioned crosslinking agent, when forming the antistatic layer, the water-soluble conductive polymer or the water-dispersible conductive polymer can be fixed in the antistatic layer, and the water resistance or the solvent resistance can be improved. In terms of excellent effect.

In a preferred aspect, a blocked isocyanate-based crosslinking agent that is also stable in an aqueous solution is used as the isocyanate-based crosslinking agent. As a specific example of the above-mentioned blocked isocyanate-based cross-linking agent, an isocyanate-based cross-linking agent (for example, an isocyanate compound used in the following adhesive layer ( Isocyanate-based crosslinking agent)) to alcohols, phenols, thiophenols, amines, amines, oximes, lactams, reactive methylene compounds, thiols, imines, Ureas, diaryl compounds, and sodium bisulfite are capped and obtained.

Generally, an antistatic agent composition for forming an antistatic layer contains a surfactant, a leveling agent, a lubricant, and the like. With these, the occurrence of shrinkage or uneven thickness during coating can be suppressed. These additives form a fragile layer in the antistatic layer, peeling occurs at the interface where the antistatic layer is in contact with the adhesive layer, and so it is preferable not to mix these additives. In addition, in addition to the above-mentioned conductive polymer, other antistatic ingredients or antioxidants, colorants (pigments, dyes, etc.), fluidity modifiers (thixotropic agents, tackifiers, etc.), manufacturing agents, etc. Additives such as film auxiliaries, surfactants (antifoaming agents, etc.), and preservatives.

＜ Formation of antistatic layer ＞
The antistatic layer may include a liquid composition (a coating material for forming an antistatic layer, etc.) obtained by dissolving the above-mentioned conductive polymer component, and optionally used additives in an appropriate solvent (water, etc.). The antistatic agent composition) is preferably formed by a method for imparting a base film. For example, a method of applying the above-mentioned coating material to one surface of a base film and drying it, and performing a hardening treatment (heat treatment, ultraviolet treatment, etc.) as necessary may be preferably used. The NV (non-volatile component) of the coating material may be, for example, 5% by weight or less (typically 0.05 to 5% by weight), and generally suitable is 1% by weight or less (typically 0.10 to 1% by weight). When forming a thin antistatic layer, the NV of the coating material is preferably, for example, 0.05 to 0.50% by weight (for example, 0.10 to 0.40% by weight). By using such a low NV coating material, a more uniform antistatic layer can be formed.

The solvent constituting the coating material for forming the antistatic layer is preferably one that can stabilize and dissolve (disperse) the constituents of the antistatic layer. The solvent may be an organic solvent, water, or a mixed solvent thereof. As the organic solvent, for example, esters selected from ethyl acetate and the like; ketones such as methyl ethyl ketone, acetone, and cyclohexanone; cyclic ethers such as tetrahydrofuran (THF) and dioxane; n-hexane and cyclic Aliphatic or alicyclic hydrocarbons such as hexane; aromatic hydrocarbons such as toluene and xylene; aliphatic or alicyclic alcohols such as methanol, ethanol, n-propanol, isopropanol, cyclohexanol; alkylene One or two or more kinds of glycol monoalkyl ethers (for example, glycol monomethyl ether, ethylene glycol monoethyl ether), glycol ethers such as dialkylene glycol monoalkyl ether, and the like. In a preferred aspect, the solvent of the coating material is water or a mixed solvent containing water as a main component (for example, a mixed solvent of water and ethanol).

＜ Properties of antistatic layer ＞
The thickness of the antistatic layer in the technology disclosed here is typically 3 to 500 nm, preferably 3 to 100 nm, and more preferably 3 to 60 nm. If the thickness of the antistatic layer is too small, it is difficult to form the antistatic layer uniformly (for example, in the thickness of the antistatic layer, the thickness difference varies depending on the location). Therefore, the appearance of the surface protective film may be easily uneven. On the other hand, if the thickness is too thick, it may affect the characteristics (optical characteristics, dimensional stability, etc.) of the base film.

The surface resistance value (Ω / □) measured on the surface of the antistatic layer disclosed herein is 1.0 × 10 ¹⁰ or less, preferably 1.0 × 10 ⁴ to 5.0 × 10 ⁹ , and more preferably 1.0 × 10 ⁵ ~ 4.0 × 10 ⁹ , and more preferably 3.0 × 10 ⁵ to 3.0 × 10 ⁹ . The surface protection film showing the surface resistance value within the above range can be preferably used as a surface protection film used in the processing or transportation of static-proof articles such as liquid crystal cells or semiconductor devices. In addition, the surface protection film showing the surface resistance value within the above range can perform operation confirmation even when a polarizing plate is mounted on the touch panel sensor and a surface protective film is attached to the polarizing plate. Thus useful. The surface resistance value can be calculated from a surface resistance value measured in a 23 ° C, 50% RH environment using a commercially available insulation resistance measuring device (resistivity meter, etc.).

＜ Adhesive layer ＞
The surface protection film of the present invention is characterized in that it has a substrate film containing a resin material, and a (meth) acrylic polymer as a base polymer and an antistatic component on one side of the substrate film. An adhesive layer formed from an adhesive composition of an ionic compound.

As the (meth) acrylic polymer, the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms (the alkyl group having 1 to 14 carbon atoms) can be used as a raw material monomer constituting the raw material monomer. Alkyl (meth) acrylate). As the (meth) acrylic monomer, one kind or two or more kinds can be used as a main component. By using the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, the adhesion to the adherend (protected body) can be easily controlled to be low, and light peelability or re-peeling can be obtained. Excellent surface protection film. The (meth) acrylic polymer in the present invention refers to an acrylic polymer and / or a methacrylic polymer, and the (meth) acrylate refers to an acrylate and / or a methacrylic acid. ester.

Specific examples of the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, and (meth) acrylic acid Butyl ester, second butyl (meth) acrylate, third butyl (meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate Ester, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, (meth) ) Isodecyl acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, and the like.

Among the surface protective films of the present invention, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, N-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, iso-decyl (meth) acrylate, n-dodecyl (meth) acrylate, (formyl) (Meth) acrylic monomers having an alkyl group having 6 to 14 carbons such as n-tridecyl acrylate and n-tetradecyl (meth) acrylate are preferred. In particular, by using a (meth) acrylic monomer having an alkyl group having 6 to 14 carbon atoms, it is easy to control the adhesion to the adherend to be low, and it becomes an excellent re-peelability.

As the above-mentioned adhesive composition, it is preferably 60% by weight or more of an alkyl group having an alkyl group having 1 to 14% by weight based on 100% by weight of the total monomer components constituting the (meth) acrylic polymer. The acrylic monomer is more preferably 70% by weight or more, more preferably 80% by weight or more, and most preferably 90 to 99% by weight. If it is less than 60% by weight, the moderate wettability of the adhesive composition or the cohesive force of the adhesive layer becomes poor, which is not good.

Moreover, as said adhesive composition, it is preferable that the said (meth) acrylic-type polymer contains the (meth) acrylic-type monomer which has a hydroxyl group as a raw material monomer. As the (meth) acrylic monomer having a hydroxyl group, one kind or two or more kinds can be used as a main component.

By using the aforementioned (meth) acrylic monomer having a hydroxyl group, it is easy to control the cross-linking of the adhesive composition, etc., and thus it is easy to control the balance between the improvement of the wettability caused by the flow and the reduction of the adhesive force during peeling.

Examples of the (meth) acrylic monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate. , 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxyacrylic acid) Methyl cyclohexyl) methyl ester, N-hydroxymethyl (meth) acrylamide and the like. In particular, the use of a (meth) acrylic monomer having a hydroxyl group having an alkyl group having a carbon number of 4 or more is preferable because light peeling at the time of high-speed peeling becomes easy.

With respect to 100 parts by weight of the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, it is preferred that the (meth) acrylic monomer having a hydroxyl group contains 20 parts by weight or less, and more preferably 1 to 18 parts by weight, more preferably 2 to 15 parts by weight, and most preferably 3 to 12 parts by weight. If it is in the said range, since it is easy to control the balance of the wettability of an adhesive composition and the cohesive force of the obtained adhesive layer, it is preferable.

In addition, as another polymerizable monomer component, for the reason that it is easy to obtain the balance of the adhesion performance, it can be used in a way that the Tg becomes 0 ° C or lower (usually -100 ° C or higher) within a range that does not impair the effect of the present invention. It is used to adjust the glass transition temperature of the (meth) acrylic polymer or the peelable polymerizable monomer.

Other than the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms and the (meth) acrylic monomer having a hydroxyl group used as the (meth) acrylic polymer As the polymerizable monomer, a (meth) acrylic monomer having a carboxyl group can be used.

Examples of the (meth) acrylic monomer having a carboxyl group include (meth) acrylic acid, carboxyethyl (meth) acrylate, and carboxypentyl (meth) acrylate.

The (meth) acrylic monomer having a carboxyl group is preferably contained in an amount of 5 parts by weight or less with respect to 100 parts by weight of the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, and more preferably 2 It is preferably 0.001 to 1 part by weight, and most preferably 0.01 to 0.1 part by weight. If it is in the said range, since it is easy to control the balance of the wettability of an adhesive composition and the cohesive force of the obtained adhesive layer, it is preferable.

Furthermore, as the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, the (meth) acrylic monomer having a hydroxyl group, and the The polymerizable monomer other than the carboxyl (meth) acrylic monomer may be used without particular limitation as long as it is within a range that does not impair the characteristics of the present invention. For example, it can be suitably used: cyano group-containing monomers, vinyl ester monomers, aromatic vinyl monomers, and other components that improve cohesion and heat resistance, or fluorenamine-containing monomers, and fluorenimine-containing monomers. Amine-containing monomers, epoxy-containing monomers, N-acrylic hydrazines, vinyl ether monomers, and other components that improve adhesion or have functional groups that function as cross-linking sites. These polymerizable monomers may be used alone or in combination of two or more.

Examples of the cyano group-containing monomer include acrylonitrile and methacrylonitrile.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, and vinyl laurate.

Examples of the aromatic vinyl monomer include styrene, chlorostyrene, chloromethylstyrene, α-methylstyrene, and other substituted styrenes.

Examples of the amidino group-containing monomer include acrylamide, methacrylamide, diethylacrylamide, N-vinylpyrrolidone, N, N-dimethylacrylamide, and N , N-dimethylmethacrylamide, N, N-diethylmethacrylamide, N, N-diethylmethacrylamide, N, N'-methylenebispropenylamine, N , N-dimethylaminopropylacrylamide, N, N-dimethylaminopropylmethacrylamine, diacetoneacrylamide and the like.

Examples of the fluorenimine-containing monomer include cyclohexylcisbutenedifluoreneimide, isopropylcisbutenedifluoreneimide, N-cyclohexylcisbutenedifluoreneimine, and Ikonam Imine and so on.

Examples of the amine group-containing monomer include aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, and N, N-dimethylamine (meth) acrylate. Propyl ester, etc.

Examples of the epoxy-group-containing monomer include glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate, and allyl glycidyl ether.

Examples of the vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, and isobutyl vinyl ether.

The (meth) acrylic polymer may further contain an alkylene oxide-containing reactive monomer as a monomer component.

In addition, the average addition mole number of the oxyalkylene unit as the above-mentioned alkylene oxide-containing reactive monomer is preferably 1 from the viewpoint of compatibility with an ionic compound as an antistatic component. ~ 40, more preferably 3 ~ 40, even more preferably 4 ~ 35, particularly preferably 5 ~ 30. When the average addition mole number is 1 or more, there is a tendency that the pollution reduction effect of the adherend (protected body) can be obtained efficiently. In addition, when the average addition mole number is greater than 40, the interaction with the ionic compound becomes large, and the viscosity of the adhesive composition tends to increase, which tends to make coating difficult, which is not preferable. Furthermore, the end of the oxyalkylene chain may be maintained as a hydroxyl group or substituted with another functional group or the like.

The above-mentioned alkylene oxide-containing reactive monomers may be used alone or in combination of two or more kinds. The total content is preferably 20% by weight based on the total monomer component of the (meth) acrylic polymer. % Or less, more preferably 10% by weight or less, still more preferably 5% by weight or less, still more preferably 4% by weight or less, even more preferably 3% by weight or less, even more preferably 1% by weight or less. If the content of the alkylene oxide-containing reactive monomer exceeds 20% by weight, the interaction with the ionic compound becomes large, the ion conduction is hindered, and the antistatic property is reduced, which is not good.

Examples of the oxyalkylene unit of the above-mentioned alkylene oxide-containing reactive monomer include those having 1 to 6 carbon atoms. Examples include oxymethylene, oxyethyl, and oxypropylene. Base, oxybutyl, etc. The hydrocarbon group of the oxyalkylene chain may be straight or branched.

In addition, the above-mentioned alkylene oxide-containing reactive monomer is more preferably a reactive monomer having an ethylene oxide group. By using a (meth) acrylic polymer having a reactive monomer having an ethylene oxide group as a base polymer, the compatibility between the base polymer and the ionic compound is improved, and the adhesion to the adherend can be well suppressed. Exudation to obtain a low-contamination adhesive composition.

Examples of the above-mentioned alkylene oxide-containing reactive monomer include (meth) acrylic acid alkylene oxide adducts or reactive substituents such as acrylfluorenyl group, methacrylfluorenyl group, and allyl group in the molecule. Reactive surfactants.

Specific examples of the (meth) acrylic acid alkylene oxide adducts include, for example, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, and polyethylene glycol-polypropylene glycol (formaldehyde). Base) acrylate, polyethylene glycol-polybutylene glycol (meth) acrylate, polypropylene glycol-polybutylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, ethyl acetate Oxypolyethylene glycol (meth) acrylate, butoxy polyethylene glycol (meth) acrylate, octyloxy polyethylene glycol (meth) acrylate, lauryloxy polyethylene glycol (formaldehyde Base) acrylate, stearyloxypolyethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, octyloxypoly Ethylene glycol-polypropylene glycol (meth) acrylate and the like.

Specific examples of the reactive surfactant include, for example, an anionic reactive surfactant having a (meth) acrylfluorenyl group or an allyl group, a nonionic reactive surfactant, and a cationic reaction. Sexual surfactants and so on.

In the present invention, the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, the (meth) acrylic monomer having a hydroxyl group, and the (meth) acrylic monomer having a carboxyl group The polymerizable monomer preferably contains 0 to 20 parts by weight, more preferably 0 to 10 parts by weight, based on 100 parts by weight of the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms. By controlling the blending within the above range, it is possible to appropriately adjust good re-peelability, which is preferable.

The weight average molecular weight (Mw) of the (meth) acrylic polymer is preferably 100,000 to 3 million, more preferably 200,000 to 2 million, and even more preferably 300,000 to 1 million. When the weight average molecular weight is less than 100,000, there is a tendency that a paste residue tends to occur because the cohesive force of the adhesive layer becomes small. On the other hand, when the weight average molecular weight exceeds 3 million, the fluidity of the polymer decreases, and the wetting of the adherend (for example, a polarizing plate) becomes insufficient, and there is an adhesive that becomes an adherend and a surface protective film. Tendency to cause bulging between layers. The weight-average molecular weight (Mw) refers to those obtained by GPC (gel permeation chromatography) measurement.

The glass transition temperature (Tg) of the (meth) acrylic polymer is preferably 0 ° C or lower, and more preferably -10 ° C or lower (normally -100 ° C or higher). When the glass transition temperature is higher than 0 ° C, the polymer is difficult to flow, for example, the wetting of the polarizing plate becomes insufficient, and there is a tendency that a bulging occurs between the polarizing plate and the adhesive layer of the surface protective film. In particular, by setting the glass transition temperature to -60 ° C or lower, it is easy to obtain an adhesive layer having excellent wettability and light peelability to a polarizing plate. The glass transition temperature of the (meth) acrylic polymer can be adjusted within the above range by appropriately changing the monomer component or composition ratio used.

For the production of such (meth) acrylic polymers, well-known production methods such as solution polymerization, block polymerization, emulsification polymerization, and various radical polymerizations can be appropriately selected. Among them, it is preferable in terms of simplicity or versatility. For solution polymerization, living radical polymerization is preferred in terms of ensuring low-molecular-weight oligomer formation and ensuring pollution resistance and productivity even when the polymerization rate is increased. The obtained (meth) acrylic polymer may be any of a random copolymer, a block copolymer, and a graft copolymer.

In the solution polymerization, as the polymerization solvent, for example, ethyl acetate and toluene are used. As a specific solution polymerization example, the reaction is performed under the following reaction conditions: a polymerization initiator is added under an inert gas flow such as nitrogen, and the reaction is usually performed at about 50 to 70 ° C for about 10 minutes to 30 hours. In particular, by shortening the polymerization time to about 30 minutes to 3 hours, the generation of low-molecular-weight oligomers formed at the later stage of polymerization can be suppressed, thereby improving the adhesiveness of the adhesive.

The polymerization initiator, chain transfer agent, emulsifier, and the like used in the radical polymerization are not particularly limited, and may be appropriately selected and used. Furthermore, the weight average molecular weight of the (meth) acrylic polymer can be controlled by the amount of polymerization initiator, chain transfer agent used, and reaction conditions, and the appropriate amount of use can be adjusted according to the type of these.

The polymerization initiator is not particularly limited, and examples thereof include a peroxide-based polymerization initiator and an azo-based polymerization initiator. The peroxide-based polymerization initiator is not particularly limited, and examples thereof include peroxycarbonate, ketone peroxide, peroxyketal, hydrogen peroxide, dialkyl peroxide, difluorenyl peroxide, Peroxyesters and the like, more specifically, benzamidine peroxide, tertiary butyl hydroperoxide, tertiary butyl peroxide, tertiary butyl peroxybenzoate, and dicumyl peroxide , 1,1-bis (third butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (third butylperoxy) cyclododecane, and the like. The azo-based polymerization initiator is not particularly limited, and examples thereof include 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, and 2,2 '-Azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylpropanoic acid) dimethyl ester, 2,2'-azobis (4-methoxy -2,4-dimethylvaleronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis (2,4,4-trimethyl Pentane), 4,4'-azobis-4-cyanovaleric acid, 2,2'-azobis (2-fluorenylpropane) dihydrochloride, 2,2'-azobis [2 -(5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis (2-methylpropionamidine) disulfate, 2,2'-azo Bis (N, N'-dimethylmethylene isobutyl hydrazone) hydrochloride, 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropylhydrazone] hydrate, and the like. The above-mentioned polymerization initiators may be used alone or in combination of two or more.

Examples of the polymerization initiator used in the living radical polymerization include organic tellurium compounds. Examples of the organic tellurium compound include (methyl telluryl-methyl) benzene, (1-methyl telluryl-ethyl) benzene, (2-methyl telluryl-propyl) benzene, 1-chloro-4- (methyl telluryl-methyl) benzene, 1-hydroxy-4- (methyl telluryl-methyl) benzene, 1-methoxy-4- (methyl telluryl -Methyl) benzene, 1-amino-4- (methyl telluryl-methyl) benzene, 1-nitro-4- (methyl telluryl-methyl) benzene, 1-cyano-4 -(Methyl telluryl-methyl) benzene, 1-methylcarbonyl-4- (methyl telluryl-methyl) benzene, 1-phenylcarbonyl-4- (methyl telluryl-methyl) ) Benzene, 1-methoxycarbonyl-4- (methyl telluryl-methyl) benzene, 1-phenoxycarbonyl-4- (methyl telluryl-methyl) benzene, 1-sulfonyl 4- (methyl telluryl-methyl) benzene, 1-trifluoromethyl-4- (methyl telluryl-methyl) benzene, 1-chloro-4- (1-methyl telluryl -Ethyl) benzene, 1-hydroxy-4- (1-methyl telluryl-ethyl) benzene, 1-methoxy-4- (1-methyl telluryl-ethyl) benzene, 1- Amino-4- (1-methyl telluryl-ethyl) benzene, 1-nitro-4- (1-methyl telluryl-ethyl) benzene, 1-cyano-4- (1- Methyl telluryl-ethyl) benzene, 1-methylcarbonyl-4- (1-methyl telluryl-ethyl) benzene, 1-phenylcarbonyl-4- (1-methyl telluryl-ethyl) benzene, 1-methoxycarbonyl-4- (1-methyl telluryl-ethyl) benzene, 1-phenoxycarbonyl-4- (1-methyl Alkyl telluryl-ethyl) benzene, 1-sulfofluorenyl-4- (1-methyl telluryl-ethyl) benzene, 1-trifluoromethyl-4- (1-methyl telluryl- Ethyl) benzene, 1-chloro-4- (2-methyl telluryl-propyl) benzene, 1-hydroxy-4- (2-methyl telluryl-propyl) benzene, 1-methoxy 4- (2-methyl telluryl-propyl) benzene, 1-amino-4- (2-methyl telluryl-propyl) benzene, 1-nitro-4- (2-methyl Telluryl-propyl) benzene, 1-cyano-4- (2-methyl telluryl-propyl) benzene, 1-methylcarbonyl-4- (2-methyl telluryl-propyl) Benzene, 1-phenylcarbonyl-4- (2-methyltelluryl-propyl) benzene, 1-methoxycarbonyl-4- (2-methyltelluryl-propyl) benzene, 1-benzene Oxycarbonyl-4- (2-methyl telluryl-propyl) benzene, 1-sulfonyl-4- (2-methyl telluryl-propyl) benzene, 1-trifluoromethyl-4 -(2-methyl telluryl-propyl) benzene, 2- (methyl telluryl-methyl) pyridine, 2- (1-methyl telluryl-ethyl) pyridine, 2- (2- Methyl telluryl-propyl) pyridine, 2-methyl telluryl-methyl acetate, 2-methyl telluryl-methyl propionate, 2-methyl telluryl-2-methyl propionic acid Methyl ester 2-methyl telluryl-ethyl acetate, 2-methyl telluryl-ethyl propionate, 2-methyl-2-methyl telluryl-ethyl propionate, 2-methyl telluryl Acetonitrile, 2-methyl telluryl propionitrile, 2-methyl-2-methyl telluryl propionitrile, and the like. The methyl telluryl groups in these organic tellurium compounds may also be ethyl telluryl, n-propyl telluryl, isopropyl telluryl, n-butyl telluryl, isobutyl telluryl, Tributyltelluryl, phenyltelluryl and the like. The above-mentioned polymerization initiators may be used alone or in combination of two or more.

The blending ratio of the polymerization initiator (the entire polymerization initiator) is not particularly limited. For example, it is preferably 0.005 to 100% by weight based on the total amount of monomer components (100 parts by weight) constituting the (meth) acrylic polymer. 5 parts by weight, more preferably 0.01 to 3 parts by weight.

<Antistatic component in the adhesive layer>
The surface protection film of the present invention is characterized by having an adhesive layer (adhesive layer having antistatic properties) formed from an adhesive composition containing an ionic compound as an antistatic component. Examples of the ionic compound include an alkali metal salt and / or an ionic liquid. By containing such an ionic compound, excellent antistatic properties can be imparted. In addition, as described above, an adhesive layer (using an antistatic component) obtained by cross-linking an adhesive composition containing an antistatic component can resist resistance to an adherend (such as a polarizing plate) that is not antistatic during peeling. Static electricity becomes a surface protection film that reduces pollution to adherends. Therefore, it is very useful as an antistatic surface protective film in the technical field related to optical and electronic parts where electrification or pollution becomes a particularly serious problem.

The above-mentioned alkali metal salt has a high ion dissociation property, so it can exhibit excellent antistatic ability even in a small amount of addition, which is preferable in this respect. Examples of the alkali metal salt, for example, may be used preferably comprise comprising Li ^+, Na ^+, K ⁺ and the cations comprising ^{Cl -, Br -, I -} , AlCl 4 -, Al 2 Cl 7 -, BF 4 -, PF 6 _{^{-, SCN -, ClO 4 -}} , NO 3 -, CH 3 COO -, C 9 H 19 COO -, CF 3 COO -, C 3 F 7 COO -, CH 3 SO 3 -, CF 3 SO 3 -, C ^{_{4 F 9 SO 3 -, C}} 2 H 5 OSO 3 -, C 6 H 13 OSO 3 -, C 8 H 17 OSO 3 -, (CF 3 SO 2) 2 N -, (C 2 F 5 SO 2) 2 _{^{N -, (C 3 F 7}} SO 2) 2 N -, (C 4 F 9 SO 2) 2 N -, (CF 3 SO 2) 3 C -, AsF 6 -, SbF 6 -, NbF 6 -, TaF _{^{6 -, HF 2 - (CN}} ) 2 N -, (CF 3 SO 2) (CF 3 CO) N -, (CH 3) 2 PO 4 -, (C 2 H 5) 2 PO 4 -, CH 3 ( _{OC 2 H 4) 2 OSO 3} -, C 6 H 4 (CH 3) SO 3 -, (C 2 F 5) 3 PF 3 -, CH 3 CH (OH) COO - and (FSO _{2) 2} N ^- of Anion metal salt. More preferably, LiBr, LiI, LiBF ₄ , LiPF ₆ , LiSCN, LiClO ₄ , LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, Li (C ₂ F ₅ SO ₂ ) ₂ N, Li (FSO ₂ ) ₂ N, lithium salts such as Li (CF ₃ SO ₂ ) ₃ C, and more preferably LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, Li (C ₂ F ₅ SO ₂ ) ₂ N, Li (C ₃ F ₇ SO ₂ ) ₂ N, Li (C ₄ F ₉ SO ₂ ) ₂ N, Li (FSO ₂ ) ₂ N, Li (CF ₃ SO ₂ ) ₃ C. These alkali metal salts can be used alone or in combination of two or more.

Moreover, by using the above-mentioned ionic liquid as an antistatic component (antistatic agent), it is possible to obtain an adhesive layer that does not impair the adhesive properties and has a high antistatic effect. The detailed reason why the ionic liquid is used to obtain excellent antistatic properties is not clear, but it can be considered as follows: the ionic liquid has a lower melting point (a melting point of 100 ° C or lower) compared with a general ionic compound, so that molecular movement is easy , Can obtain excellent antistatic ability. In particular, when antistatic to an adherend is sought, a very small amount of ionic liquid is transferred to the adherend, whereby excellent peeling antistatic properties in the adherend can be sought. In particular, an ionic liquid having a melting point of room temperature (25 ° C) or less can be transferred to an adherend more effectively, so excellent antistatic properties can be obtained.

In addition, the ionic liquid is liquid at any temperature of 100 ° C. or lower, so that it can be easily added to, dispersed or dissolved in an adhesive as compared with a solid salt. Furthermore, the ionic liquid has no vapor pressure (non-volatile), so it does not disappear over time, and has the characteristic of continuously obtaining antistatic properties. The ionic liquid system refers to a molten salt (ionic compound) having a melting point of 100 ° C. or lower.

As the ionic liquid, those containing an organic cation component and an anion component represented by the following general formulae (A) to (E) can be preferably used. With ionic liquids having these cations, those with better antistatic ability can be obtained.

[Chemical 1]

In the formula (A), R _a represents _a hydrocarbon group having 4 to 20 carbon atoms, and may be a functional group in which a part of the above hydrocarbon group is substituted with a hetero atom. R _b and R _{c are the} same or different and represent hydrogen or a carbon number of 1 to 16 The hydrocarbon group may be a functional group in which a part of the hydrocarbon group is substituted with a hetero atom. However, when the nitrogen atom contains a double bond, R _c does not exist.

The above-described formula (B), the R _d represents a C1-2 hydrocarbon group of 2 to 20 of which may be heteroatom substituted with the atom functional group is part of the hydrocarbon groups, R _e, the same or different R _f and R _g, represents hydrogen or a C The hydrocarbon group of 16 may be a functional group in which a part of the above-mentioned hydrocarbon group is substituted with a hetero atom.

The above formula (C), the R _h represents a C1-2 hydrocarbon group of 2 to 20 of which may be heteroatom substituted with the atom functional group is part of the hydrocarbon groups, R _i, identical or different, R _j and R _k, represents hydrogen or a C The hydrocarbon group of 16 may be a functional group in which a part of the above-mentioned hydrocarbon group is substituted with a hetero atom.

Z in the above formula (D) represents a nitrogen, sulfur or phosphorus atom, R ₁ , R _m , R _n and R _{o are the} same or different and represent a hydrocarbon group having 1 to 20 carbon atoms, and a part of the above hydrocarbon group may be substituted with a hetero atom Of functional groups. In the case where Z is a sulfur atom, R _o does not exist.

R _P in the above formula (E) represents a hydrocarbon group having 1 to 18 carbon atoms, and may be a functional group in which a part of the above hydrocarbon group is substituted with a hetero atom.

Examples of the cation represented by the formula (A) include a pyridinium cation, a piperidinium cation, a pyrrolidinium cation, a cation having a pyrroline skeleton, a cation having a pyrrole skeleton, and a phosphonium cation.

Specific examples include 1-butylpyridinium cation, 1-hexylpyridinium cation, 1-butyl-3-methylpyridinium cation, 1-butyl-3,4-dimethylpyridinium Cation, 1-methyl-1-ethylpyrrolidinium cation, 1-methyl-1-hexylpyrrolidinium cation, 1-ethyl-1-hexylpyrrolidinium cation, pyrrolidin-2-one cation , 1-propylpiperidinium cation, 1-methyl-1-ethylpiperidinium cation, 1-methyl-1-hexylpiperidinium cation, 2-methyl-1-pyrroline cation, 1- Ethyl-2-phenylindole cation, 1,2-dimethylindole cation, 1-ethylcarbazole cation, N-ethyl-N-methylium cation, and the like.

Examples of the cation represented by the formula (B) include an imidazolium cation, a tetrahydropyrimidinium cation, and a dihydropyrimidinium cation.

Specific examples include 1,3-dimethylimidazolium cation, 1-ethyl-3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, and 1-octyl-3 -Methylimidazolium cation, 1-decyl-3-methylimidazolium cation, 1-tetradecyl-3-methylimidazolium cation, 1- (2-methoxyethyl) -3-methyl Imidazolium cation, 1,3-dimethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,2,3-trimethyl-1,4,5,6-tetrahydropyrimidinium cation 1,2,3,5-tetramethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,3-dimethyl-1,4-dihydropyrimidinium cation, 1,3-di Methyl-1,6-dihydropyrimidinium cation, 1,2,3-trimethyl-1,4-dihydropyrimidinium cation, 1,2,3,4-tetramethyl-1,6-di Hydropyrimidinium cations and the like.

Examples of the cation represented by the formula (C) include a pyrazolium cation and a pyrazolinium cation.

Specific examples include 1-methylpyrazolium cation, 3-methylpyrazolium cation, 1-ethyl-2-methylpyrazolinium cation, 1-ethyl-2,3, 5-trimethylpyrazolium cation, 1-propyl-2,3,5-trimethylpyrazolium cation, 1-butyl-2,3,5-trimethylpyrazolium cation, 1- Ethyl-2,3,5-trimethylpyrazolinium cation, 1-propyl-2,3,5-trimethylpyrazolinium cation, 1-butyl-2,3,5-tri Methylpyrazolinium cations and the like.

Examples of the cation represented by the formula (D) include a tetraalkylammonium cation, a trialkylphosphonium cation, a tetraalkylphosphonium cation, or a part of the alkyl group substituted with an alkenyl group or an alkoxy group, and further a ring Oxygen and so on.

Specific examples include tetramethylammonium cation, tetrabutylammonium cation, tetrapentylammonium cation, tetrahexylammonium cation, triethylmethylammonium cation, tributylethylammonium cation, and trimethyl Decylammonium cation, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium cation, glycidyl trimethylammonium cation, trimethylphosphonium cation, triethyl Sulfonium cation, tributylsulfonium cation, trihexylsulfonium cation, diethylmethylsulfonium cation, dibutylethylsulfonium cation, dimethyldecylsulfonium cation, tetramethylsulfonium cation, tetraethylsulfonium cation, Tetrabutylphosphonium cation, tetrahexylphosphonium cation, tetraoctylphosphonium cation, triethylmethylphosphonium cation, tributylethylphosphonium cation, trimethyldecylphosphonium cation, diallyldimethylammonium cation , Tributyl- (2-methoxyethyl) phosphonium cation, and the like. Among them, triethylmethylammonium cation, tributylethylammonium cation, trimethyldecylammonium cation, diethylmethylphosphonium cation, dibutylethylphosphonium cation, dimethyl Asymmetric tetraalkylammonium cations such as decylsulfonium cation, triethylmethylsulfonium cation, tributylethylsulfonium cation, trimethyldecylsulfonium cation, trialkylsulfonium cation, tetraalkylsulfonium cation, or N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium cation, glycidyl trimethylammonium cation, diallyldimethylammonium cation, N, N- Dimethyl-N-ethyl-N-heptylammonium cation, N, N-dimethyl-N-ethyl-N-nonylammonium cation, N, N-dimethyl-N-propyl-N -Pentylammonium cation, N, N-dimethyl-N-propyl-N-hexylammonium cation, N, N-dimethyl-N-propyl-N-heptylammonium cation, trimethylheptyl Ammonium cation, N, N-diethyl-N-methyl-N-propylammonium cation, N, N-diethyl-N-methyl-N-pentylammonium cation, N, N-diethyl -N-methyl-N-heptylammonium cation, N, N-diethyl-N-propyl-N-pentylammonium cation, trioctylmethylammonium cation, N-methyl-N- Ethyl-N-propyl-N-pentylammonium cation.

Examples of the cation represented by the formula (E) include a sulfonium cation. Specific examples of R _P in the formula (E) include methyl, ethyl, propyl, butyl, hexyl, octyl, nonyl, decyl, dodecyl, and tridecane. Alkyl, tetradecyl, octadecyl and the like.

On the other hand, the anionic component becomes an ionic liquid as long as it satisfies who is not particularly limited, for example, may be ^{used: Cl -, Br -, I} -, AlCl 4 -, Al 2 Cl 7 -, BF 4 -, PF _{^{6 -, ClO 4 -, NO}} 3 -, CH 3 COO -, CF 3 COO -, CH 3 SO 3 -, CF 3 SO 3 -, C 4 F 9 SO 3 -, (CF 3 SO 2) 2 N - _{, (C 2 F 5 SO 2} ) 2 N -, (C 3 F 7 SO 2) 2 N -, (C 4 F 9 SO 2) 2 N -, (CF 3 SO 2) 3 C -, AsF 6 - _{^{, SbF 6 -, NbF 6 -}} , TaF 6 -, HF 2 -, (CN) 2 N -, C 4 F 9 SO 3 -, (C 2 F 5 SO 2) 2 N -, C 3 F 7 COO - _{, (CF 3 SO 2) (} CF 3 CO) N -, C 9 H 19 COO -, (CH 3) 2 PO 4 -, (C 2 H 5) 2 PO 4 -, C 2 H 5 OSO 3 -, ^{_{C 6 H 13 OSO 3 -,}} C 8 H 17 OSO 3 -, CH 3 (OC 2 H 4) 2 OSO 3 -, C 6 H 4 (CH 3) SO 3 -, (C 2 F 5) 3 PF 3 ^- , CH ₃ CH (OH) COO ^- and (FSO ₂ ) ₂ N ^- and so on.

Moreover, as an anionic component, the anion etc. which are represented by following formula (F) can also be used.
[Chemical 2]

In addition, as the anionic component, in particular, in terms of obtaining an ionic liquid having a low melting point, an anionic component containing a fluorine atom can be preferably used.

As specific examples of the ionic liquid used in the present invention, it may be appropriately selected and used from the combination of the above-mentioned cationic component and anionic component, and examples thereof include 1-butylpyridinium tetrafluoroborate and 1-butylpyridine. Onium hexafluorophosphate, 1-butyl-3-methylpyridinium tetrafluoroborate, 1-butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) fluorenimine, 1-butyl 3-methylpyridinium bis (pentafluoroethanesulfonyl) fluorenimine, 1-hexylpyridinium tetrafluoroborate, 1-methyl-1-ethylpyrrolidinium bis (trifluoromethanesulfonyl) ) Fluorenimine, 1-methyl-1-hexylpyrrolidinium bis (trifluoromethanesulfonyl) fluorenimide, 1-ethyl-1-hexylpyrrolidinium bis (trifluoromethanesulfonyl) fluorene Imine, 1-propylpiperidinium bis (trifluoromethanesulfonyl) fluorenimide, 1-methyl-1-ethylpiperidinium bis (trifluoromethanesulfonyl) fluorenimide, 1- Methyl-1-hexylpiperidinium bis (trifluoromethanesulfonyl) fluorenimide, 1-methyl-1-ethylpyrrolidinium bis (pentafluoroethanesulfonyl) fluorenimine, 1-ethyl -L-hexylpyrrolidinium bis (pentafluoroethanesulfonyl) fluorenimide, 1-methyl-1-hexylpiperidinium bis (pentafluoroethanesulfonyl) fluorenimide, 2-methyl- 1- Porphyrin tetrafluoroborate, 1-ethyl-2-phenylindole tetrafluoroborate, 1,2-dimethylindole tetrafluoroborate, 1-ethylcarbazole tetrafluoroborate, 1- Ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium trifluoroacetate, 1-ethyl-3 -Methylimidazolium heptafluorobutyrate, 1-ethyl-3-methylimidazolium triflate, 1-ethyl-3-methylimidazolium perfluorobutanesulfonate, 1-ethyl 3-methylimidazolium dicyandiamide, 1-ethyl-3-methylimidazolium bis (trifluoromethanesulfonyl) fluorenimine, 1-ethyl-3-methylimidazolium bis (penta Fluoroethanesulfonyl) fluorenimine, 1-ethyl-3-methylimidazolium tris (trifluoromethanesulfonyl) methylate, 1-hexyl-3-methylimidazolium bromide, 1-hexyl 3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium hexafluorophosphate, 1-hexyl-3-methylimidazolium Trifluoromethanesulfonate, 2-methylpyrazolium tetrafluoroborate, 1-ethyl-2,3,5-trimethylpyrazolium bis (trifluoromethanesulfonyl) fluorenimine, 1 -Propyl-2,3,5-trimethylpyrazolium bis (trifluoromethanesulfonyl) fluorene Amine, 1-butyl-2,3,5-trimethylpyrazolium bis (trifluoromethanesulfonyl) phosphonium imine, tetrapentyl ammonium trifluoromethanesulfonate, tetrapentyl ammonium bis (tri Flumethanesulfonyl) fluorenimide, tetrahexylammonium triflate, tetrahexylammonium bis (trifluoromethanesulfonyl) fluorenimide, tetraheptylammonium triflate, tetraheptyl Ammonium bis (trifluoromethanesulfonyl) phosphonium imine, diallyldimethylammonium tetrafluoroborate, diallyldimethylammonium trifluoromethanesulfonate, diallyldimethylammonium Bis (trifluoromethanesulfonyl) fluorenimide, diallyldimethylammonium bis (pentafluoroethanesulfonyl) fluorenimide, N, N-diethyl-N-methyl-N- ( 2-methoxyethyl) ammonium tetrafluoroborate, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium trifluoromethanesulfonate, N, N- Diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (trifluoromethanesulfonyl) fluorenimine, N, N-diethyl-Nmethyl-N- (2 -Methoxyethyl) ammonium bis (pentafluoroethanesulfonyl) fluorenimine, glycidyl trimethylammonium triflate, glycidyl trimethylammonium bis (trifluoromethanesulfonyl) ) Fluorenimine, glycidyl trimethylammonium bis (pentafluoroethanesulfonyl) fluorenimide, tetraoctylfluorene Fmethanesulfonate, tetraoctylfluorenylbis (trifluoromethanesulfonyl) fluorenimide, N, N-dimethyl-N-ethyl-N-butylammonium bis (trifluoromethanesulfonyl) Fluorenimine, N, N-dimethyl-N-ethyl-N-heptylammonium bis (trifluoromethanesulfonyl) fluorenimine, N, N-dimethyl-N-ethyl-N- Nonylammonium bis (trifluoromethanesulfonyl) fluorenimide, N, N-dimethyl-N-propyl-N-butylammonium bis (trifluoromethanesulfonyl) fluorenimide, N, N -Dimethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) fluorenimide, trimethylheptylammonium bis (trifluoromethanesulfonyl) fluorenimide, N, N -Diethyl-N-methyl-N-propylammonium bis (trifluoromethanesulfonyl) fluorenimine, N, N-diethyl-N-methyl-N-pentylammonium bis (trifluoro Methanesulfonyl) fluorenimine, N, N-diethyl-N-methyl-N-heptylammonium bis (trifluoromethanesulfonyl) fluorenimine, N, N-diethyl-N- Propyl-N-pentylammonium bis (trifluoromethanesulfonyl) fluorenimide, trioctylmethylammonium bis (trifluoromethanesulfonyl) fluorenimide, N-methyl-N-ethyl- N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) fluorenimide, 1-butylpyridinium (trifluoromethanesulfonyl) trifluoroacetamidine, 1-butyl-3- Methylpyridinium (trifluoromethanesulfonyl) trifluoroacetamide, 1-ethyl-3-methyl Imidazolium (trifluoromethanesulfonyl) trifluoroacetamidamine, N-ethyl-N-methylphosphonium isothiocyanate, 4-ethyl-4-methylphosphonium methyl carbonate, etc. .

The ionic liquid may be used alone, or two or more kinds may be used in combination.

For example, the content of the ionic compound is preferably 0.01 to 5 parts by weight, more preferably 0.02 to 3 parts by weight, and still more preferably 0.03 to 2 parts by weight based on 100 parts by weight of the (meth) acrylic polymer. , The best is 0.05 ~ 1 parts by weight. If it is in the said range, since it is excellent in antistatic property, it is preferable.

<Organic polysiloxane with an oxyalkylene chain>
In the surface protective film of the present invention, the above-mentioned adhesive composition preferably contains an organic polysiloxane having an oxyalkylene chain as an antistatic auxiliary agent, and more preferably contains an organic polysiloxane having an oxyalkylene side chain. alkyl. It is presumed that by using the above-mentioned organopolysiloxane, the surface free energy on the surface of the adhesive is reduced and light peeling is achieved. In addition, it is estimated that the antistatic property is improved together with the ionic compound contained in the adhesive composition.

As the organic polysiloxane, a known organic polysiloxane having a polyoxyalkylene main chain can be suitably used, and it is preferably one represented by the following formula.
[Chemical 3]

(In the formula, R ₁ and / or R ₂ has an oxyalkylene chain having 1 to 6 carbon atoms. The oxyalkylene chain in the oxyalkylene chain may be straight or branched. The terminal may be an alkoxy group or a hydroxyl group; in addition, any one of R ₁ or R ₂ may be a hydroxyl group, or may be an alkyl group or an alkoxy group, or a part of the alkyl group or the alkoxy group may be a hetero atom Substituted functional groups; n is an integer from 1 to 300)

The above-mentioned organic polysiloxanes are those in which a site containing a siloxane (siloxane site) is a main chain and an oxygen alkylene chain is bonded to a terminal of the main chain. It is presumed that, by using the above-mentioned organosiloxane having an oxyalkylene chain, for example, a balance between compatibility with the (meth) acrylic polymer and the ionic compound can be obtained, and light exfoliation can be achieved.

Moreover, as the said organopolysiloxane in this invention, the following structures can be used, for example. Specifically, R ₁ and / or R ₂ in the formula has an oxyalkylene chain containing a hydrocarbon group having 1 to 6 carbon atoms. Examples of the oxyalkylene chain include oxymethylene and oxyethylene. , Oxypropyl, oxybutyl and the like, of which oxyethyl or oxypropyl is preferred. When R ₁ and R ₂ each have an oxyalkylene chain, they may be the same or different.
[Chemical 4]

The hydrocarbon group of the oxyalkylene chain may be a straight chain or a branched chain.

Further, the terminal of the oxyalkylene chain may be an alkoxy group or a hydroxyl group, and among these, an alkoxy group is more preferred. When the release film is bonded to the surface of the adhesive layer for the purpose of protecting the adhesive surface, if it is an organopolysiloxane having a hydroxyl group at the end, it sometimes interacts with the release film and releases the release film from itself. When the surface of the adhesive layer is peeled, the adhesion (peeling) force increases.

In addition, n is an integer of 1 to 300, preferably 10 to 200, and more preferably 20 to 150. If n is within the above range, a balance of compatibility with the base polymer can be obtained, which becomes a preferable aspect. Furthermore, it may have a reactive substituent such as a (meth) acrylfluorenyl group, an allyl group, or a hydroxyl group in the molecule. These organic polysiloxanes can be used alone or in combination of two or more.

Specific examples of the above-mentioned organopolysiloxane having an oxyalkylene chain include, for example, commercially available products: trade names X-22-4952, X-22-4272, X-22-6266, and KF-6004 , KF-889 (above manufactured by Shin-Etsu Chemical Industry Co., Ltd.), BY16-211, SF8427 (above manufactured by Dow Corning Toray), IM22 (made by Asahi Kasei WACKER), etc. These compounds may be used singly or in combination of two or more kinds.

Moreover, in addition to an organosiloxane having an (oxygenated) oxyalkylene chain in the main chain, an organosiloxane having an (oxygenated) alkylene chain in a side chain can also be used. The organopolysiloxane having an oxyalkylene chain in the main chain is preferably used in the case of an organosiloxane having an oxyalkylene chain in a side chain. It is easy to achieve both antistatic properties and low pollution, so it is preferable. Appearance. As the organic polysiloxane, a known organic polysiloxane having a polyoxyalkylene side chain can be suitably used, and it is preferably one represented by the following formula.
[Chemical 5]

(In the formula, R ₁ is a monovalent organic group, R ₂ , R _3, and R ₄ are alkylene groups, R ₅ is hydrogen or an organic group, and m and n are integers from 0 to 1000; wherein m and n are not Will be 0 at the same time; a and b are integers from 0 to 100; where a and b will not be 0 at the same time)

Moreover, as the said organopolysiloxane in this invention, the following structures can be used, for example. Specifically, R ₁ in the formula is a monovalent organic group exemplified by an alkyl group such as a methyl group, an ethyl group, a propyl group, an aryl group such as a phenyl group, a tolyl group, or an aralkyl group such as a benzyl group, a phenethyl group, Each may have a substituent such as a hydroxyl group. R ₂ , R ₃ and R ₄ may be an alkylene group having 1 to 8 carbon atoms such as methylene, ethylene, or propyl. Here, R ₃ and R ₄ are different alkylene groups, and R ₂ and R ₃ or R ₄ may be the same or different. In order to increase the concentration of the ionic compound which can be dissolved in the polyoxyalkylene side chain, either of R ₃ and R ₄ is preferably an ethylidene group or a propylidene group. R ₅ may be a monovalent organic group exemplified by an alkyl group such as methyl, ethyl, propyl, or the like, such as an ethyl group, a propyl group, and the like, and each may have a substituent such as a hydroxyl group. These compounds can be used alone or in combination of two or more. Furthermore, it may have a reactive substituent such as a (meth) acrylfluorenyl group, an allyl group, or a hydroxyl group in the molecule. Among the above-mentioned organosiloxanes having a polyoxyalkylene side chain, it is presumed that an organosiloxane having a polyoxyalkylene side chain having a hydroxyl terminal is easy to obtain a balance of compatibility, and is therefore preferable.
[Chemical 6]

As a specific example of the above-mentioned organosiloxane, for example, as a commercially available product, trade names are KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF -640, KF-642, KF-643, KF-6022, X-22-6191, X-22-4515, KF-6011, KF-6012, KF-6015, KF-6017, X-22-2516 (above (Manufactured by Shin-Etsu Chemical Industry Co., Ltd.), SF8428, FZ-2162, SH3749, FZ-77, L-7001, FZ-2104, FZ-2110, L-7002, FZ-2122, FZ-2164, FZ-2203, FZ- 7001, SH8400, SH8700, SF8410, SF8422 (above manufactured by Dow Corning Toray), TSF-4440, TSF-44441, TSF-4445, TSF-4450, TSF-4446, TSF-4452, TSF-4460 (Momentive Performance Materials (Manufactured by the company), BYK-333, BYK-307, BYK-377, BYK-UV3500, BYK-UV3570 (by BYK-Chemie Japan), and the like. These compounds can be used alone or in combination of two or more.

As the organosiloxane used in the present invention, the HLB (Hydrophile-Lipophile Balance) value is preferably 1 to 16, and more preferably 3 to 14. If the HLB value deviates from the above range, the contamination property to the adherend becomes poor, which is not good.

For example, the content of the organic polysiloxane is preferably 0.01 to 5 parts by weight, more preferably 0.03 to 3 parts by weight, and still more preferably 0.05 to 1 with respect to 100 parts by weight of the (meth) acrylic polymer. It is preferably 0.05 to 0.5 parts by weight. If it is in the said range, since it is easy to make compatible with antistatic property and light peelability (repeelability), it is preferable.

The above-mentioned adhesive composition may contain a polyoxyalkylene chain-containing compound as a polyether component not containing an organopolysiloxane. In particular, when the surface protective film is peeled from the optical member, and the optical member is adhered to another member with an adhesive or an adhesive, the wettability of the adhesive or the adhesive can be improved, so it can be used preferably.

Specific examples of the polyoxyalkylene chain-containing compound that does not contain the above-mentioned organic polysiloxane include polyoxyalkylene alkylamine, polyoxyalkylene diamine, and polyoxyalkylene fatty acid. Ester, polyoxyalkylene sorbitan fatty acid ester, polyoxyalkylene alkyl phenyl ether, polyoxyalkylene alkyl ether, polyoxyalkylene alkyl allyl ether, polyoxyalkylene Non-ionic surfactants such as phenyl allyl ether; polyoxyalkylene alkyl ether sulfate, polyoxyalkylene alkyl ether phosphate, polyoxyalkylene alkyl phenyl ether sulfate , Polyoxyalkylene alkyl phenyl ether phosphate ester salts and other anionic surfactants; and cationic surfactants or amphoteric surfactants with polyoxyalkylene chain (polyalkylene oxide chain), with polyoxygen Polyether compounds (and derivatives thereof) having an alkylene chain, and acrylic compounds (and derivatives thereof) having a polyoxyalkylene chain. In addition, a polyoxyalkylene chain-containing monomer can be blended into an acrylic polymer as a polyoxyalkylene chain-containing compound. The polyoxyalkylene chain-containing compound may be used alone or in combination of two or more kinds.

Specific examples of the polyether compound having a polyoxyalkylene chain include a block copolymer of polypropylene glycol (PPG) -polyethylene glycol (PEG), a block copolymer of PPG-PEG-PPG, PEG-PPG-PEG block copolymer and the like. Examples of the derivative of the above-mentioned polyether compound having a polyoxyalkylene chain include an oxyethylene group-containing compound (PPG monoalkyl ether, PEG-PPG monoalkyl ether, etc.) having an etherified terminal, and a terminal Acetylated compounds containing oxypropyl (terminally ethylated PPG, etc.) and the like.

Moreover, as a specific example of the acrylic compound which has the said polyoxyalkylene chain, the (meth) acrylate polymer which has an oxyalkylene group is mentioned. As the oxyalkylene group, when an ionic compound is used as an antistatic component, the addition mole number of the oxyalkylene unit is preferably 1 to 50 from the viewpoint of coordination of the ionic compound, and more preferably It is preferably 2-30, and more preferably 2-20. The terminal of the oxyalkylene chain may be maintained as a hydroxyl group or substituted with an alkyl group, a phenyl group, or the like.

The (meth) acrylate polymer having an oxyalkylene group is preferably a polymer containing an alkylene oxide (meth) acrylate as a monomer unit (component), and as the alkylene oxide (meth) acrylate Specific examples of the (meth) acrylate containing an ethylene glycol group include methoxy-diethylene glycol (meth) acrylate and methoxy-triethylene glycol (meth) acrylic acid. Ethoxy such as methoxy-polyethylene glycol (meth) acrylate, ethoxy-diethylene glycol (meth) acrylate, ethoxy-triethylene glycol (meth) acrylate Butyl-polyethylene glycol (meth) acrylate type, butoxy-diethylene glycol (meth) acrylate, butoxy-triethylene glycol (meth) acrylate, etc. Phenoxy-polyethylene glycol (methyl methacrylate), phenoxy-diethylene glycol (meth) acrylate, phenoxy-triethylene glycol (meth) acrylate, etc. Based) acrylate type, 2-ethylhexyl-polyethylene glycol (meth) acrylate, nonylphenol-polyethylene glycol (meth) acrylate type, methoxy-dipropylene glycol (meth) acrylic acid Methoxy-polypropylene glycol (meth) acrylic acid Type.

In addition, other monomer units (components) other than the alkylene oxide (meth) acrylate may be used as the monomer units (components). Specific examples of other monomer components include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, second butyl (meth) acrylate, and (meth) ) Tert-butyl acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, (meth) acrylic acid Isooctyl, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate Esters, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, and other acrylates and / or methacrylates having an alkyl group having 1 to 14 carbon atoms.

Furthermore, as other monomer units (components) other than the alkylene oxide (meth) acrylate, a carboxyl group-containing (meth) acrylate, a phosphate group-containing (meth) acrylate, Cyano (meth) acrylates, vinyl esters, aromatic vinyl compounds, (meth) acrylates containing anhydride groups, (meth) acrylates containing hydroxyl groups, (meth) amines containing fluorenyl groups Acrylates, amine-containing (meth) acrylates, epoxy-containing (meth) acrylates, N-acrylic phospholine, vinyl ethers, and the like.

As a more preferable aspect, the polyoxyalkylene chain-containing compound containing no organopolysiloxane is a compound having a (poly) ethylene oxide chain at least in part. By blending the (poly) ethylene oxide chain-containing compound, the compatibility between the base polymer and the antistatic component is improved, and bleeding to the adherend is well suppressed, and a low-contamination adhesive composition is obtained. Among them, particularly when a block copolymer of PPG-PEG-PPG is used, an adhesive having excellent low staining properties is obtained. As the above polyethylene oxide chain-containing compound, the weight of the (poly) ethylene oxide chain in the entire polyoxyalkylene chain-containing compound containing no organic polysiloxane is preferably 5 to 90% by weight, more preferably 5 to 85% by weight, still more preferably 5 to 80% by weight, and most preferably 5 to 75% by weight.

As the molecular weight of the polyoxyalkylene group-containing compound containing no organic polysiloxane, the number-average molecular weight (Mn) is preferably 50,000 or less, preferably 200 to 30,000, and more preferably 200 to 10,000, usually Can use 200 ~ 5000. When Mn is more than 50,000, the compatibility with the (meth) acrylic polymer described above tends to decrease, and the adhesive layer tends to whiten. If Mn is less than 200, contamination caused by the polyoxyalkylene compound may easily occur. In addition, the number average molecular weight (Mn) here means the value of polystyrene conversion obtained by GPC (gel permeation chromatography).

Specific examples of the commercially available products of the polyoxyalkylene chain-containing compound containing no organic polysiloxane include: Adeka Pluronic 17R-4, Adeka Pluronic 25R-2 (all of which are manufactured by ADEKA Corporation) ), Emulgen 120 (manufactured by Kao Corporation), AQUALON HS-10, KH-10, Noigen EA-87, EA-137, EA-157, EA-167, EA-177 (the above are manufactured by Daiichi Pharmaceutical Co., Ltd.), etc. .

The content of the polyoxyalkylene chain-containing compound containing no organic polysiloxane is, for example, 0.005 to 20 parts by weight, and preferably 0.01 to 100 parts by weight of the (meth) acrylic polymer. ~ 10 parts by weight, more preferably 0.03 to 5 parts by weight, still more preferably 0.05 to 3 parts by weight, and most preferably 0.1 to 0.9 parts by weight. If it is in the said range, since it is easy to make it compatible with the wettability with respect to a to-be-adhered body, it is preferable.

＜ crosslinking agent ＞
As the surface protective film of the present invention, it is preferable that the adhesive composition contains a crosslinking agent. In the present invention, the adhesive composition can be prepared as an adhesive layer using the adhesive composition. For example, the surface protection film (adhesive layer) which is more excellent in heat resistance can be obtained by cross-linking the structural unit, the composition ratio, the selection of the crosslinking agent, and the addition ratio of the (meth) acrylic polymer as appropriate. .

As the crosslinking agent used in the present invention, an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative, a metal chelate compound, and the like can be used. In particular, the use of the isocyanate compound is preferred. These compounds may be used alone or in combination of two or more.

Examples of the isocyanate compound include aliphatic polyisocyanates such as trimethylene diisocyanate, butylene diisocyanate, hexamethylene diisocyanate (HDI), and dimer acid diisocyanate, and cyclopentyl diisocyanate. Alicyclic isocyanates such as cyclohexyl diisocyanate, isophorone diisocyanate (IPDI), 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate (XDI) And other aromatic isocyanates, the aforementioned isocyanate compounds are bonded with urethanate, biuret, isocyanurate, uretdione, urea, carbodiimide, and uretonimine A polyisocyanate modified product obtained by modifying a bond, a perylene ditrione bond, and the like. Examples of commercially available products include: Takenate 300S, Takenate 500, Takenate D165N, Takenate D178N (above manufactured by Mitsui Chemicals), Sumidur T80, Sumidur L, Desmodur N3400 (above manufactured by Sumika Bayer Urethane), MILLIONATE MR, MILLIONATE MT, Coronate L, Coronate HL, Coronate HX (the above are manufactured by Tosoh Corporation), etc. These isocyanate compounds may be used singly or in combination of two or more kinds. A difunctional isocyanate compound and a trifunctional or more isocyanate compound may be used in combination. By using a cross-linking agent in combination, it is possible to achieve both adhesiveness and rebound resistance (adhesion to curved surfaces), and a surface protective film with more excellent adhesion reliability can be obtained.

Examples of the epoxy compound include N, N, N ', N'-tetraglycidyl-m-xylylenediamine (trade name TETRAD-X, manufactured by Mitsubishi Gas Chemical Co., Ltd.) or 1,3-bis ( N, N-diglycidylaminomethyl) cyclohexane (trade name TETRAD-C, manufactured by Mitsubishi Gas Chemical Co., Ltd.) and the like.

Examples of the melamine-based resin include hexamethylolmelamine and the like. Examples of the aziridine derivative include commercially available products such as HDU, TAZM, and TAZO (manufactured by Kakuya Kogyo Co., Ltd.).

Examples of the metal chelate compound include aluminum, iron, tin, titanium, and nickel as metal components, and examples of the chelate component include acetylene, acetamidine methyl acetate, and ethyl lactate.

The content of the cross-linking agent used in the present invention is, for example, preferably 0.01 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, and more preferably 100 parts by weight of the (meth) acrylic polymer. It contains 0.2 ~ 3 parts by weight, and most preferably contains 0.5 ~ 2 parts by weight. When the above-mentioned content is less than 0.01 parts by weight, the cross-linking formation by the cross-linking agent becomes insufficient, the cohesive force of the obtained adhesive layer becomes small, and sometimes sufficient heat resistance cannot be obtained, and it becomes a paste. Causes of agent residues. On the other hand, when the content exceeds 10 parts by weight, the cohesive force of the polymer becomes large, the fluidity decreases, and the wetting of the adherend (for example, a polarizing plate) becomes insufficient, and it becomes an adherend and an adhesive. The cause of bulging between layers (adhesive composition layer) tends to occur. Furthermore, when there are many crosslinking amounts, there exists a tendency for a peeling charging characteristic to fall.

＜ Crosslinking catalyst ＞
The adhesive composition may further contain a crosslinking catalyst for making any of the above-mentioned crosslinking reactions more efficient. As the cross-linking catalyst, for example, tin-based catalysts such as dibutyltin dilaurate, dioctyltin dilaurate, tris (acetamidineacetone) iron (triacetammonium pyruvate), and tris (hexane) can be used. -2,4-dione) iron, tris (heptane-2,4-dione) iron, tris (heptane-3,5-dione) iron, tris (5-methylhexane-2,4 -Dione) iron, tris (octane-2,4-dione) iron, tris (6-methylheptane-2,4-dione) iron, tris (2,6-dimethylheptane- 3,5-dione) iron, tris (nonane-2,4-dione) iron, tris (nonane-4,6-dione) iron, tris (2,2,6,6-tetramethyl) Heptane-3,5-dione) iron, tris (tridecane-6,8-dione) iron, tris (1-phenylbutane-1,3-dione) iron, tris (hexafluoroethyl)醯 acetone) iron, tris (ethylacetate) iron, tris (n-propylacetate) iron, tris (isopropylacetate) iron, tris (n-butylacetate) iron, tris ( Acetyl Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate Acetate) ) Iron, tris (isopropylpropionate) iron, tris (n-butylpropionate) iron, tris (second butylpropionate) iron, tris (third butylpropionate) iron, (Benzylacetate) iron, tris (dimethyl malonate) iron, tris (diethyl malonate) iron, trimethoxy iron, triethoxy iron, triisopropoxy iron, chlorine Iron-based catalysts such as iron. These crosslinking catalysts may be used singly or in combination of two or more kinds.

The content (amount of use) of the cross-linking catalyst is not particularly limited. For example, it is preferably 0.0001 to 1 part by weight, and more preferably 0.001 to 0.5 part by weight based on 100 parts by weight of the (meth) acrylic polymer. If it is in the said range, the speed of a crosslinking reaction when forming an adhesive layer becomes fast, and it becomes a preferable aspect.

＜ Crosslinking Delaying Agent ＞
The adhesive composition may further contain a crosslinking retarder. The crosslinking delaying agent is not particularly limited, and examples thereof include methyl ethyl acetate, ethyl ethyl acetate, ethyl ethyl acetate, oleyl ethyl acetate, lauryl ethyl acetate, and hard ethyl acetate Β-ketoesters such as fatty esters, β-diketones such as acetoacetone, 2,4-hexanedione, and benzophenone, or isopropanol. Among them, acetoacetone can be used. These crosslinking delaying agents can be used alone or in combination of two or more.

The content (amount of use) of the cross-linking retarder is not particularly limited. For example, it is preferably 0.1 to 10 parts by weight, and more preferably 0.1 to 5 parts by weight based on 100 parts by weight of the solvent (in the case of conversion). If it is the said range, the usable time (use period) of an adhesive (adhesive composition) can be extended, and it becomes a preferable aspect.

＜ (meth) acrylic oligomer ＞
Furthermore, a (meth) acrylic-type oligomer may be contained in the said adhesive composition. The weight average molecular weight (Mw) of the (meth) acrylic oligomer is preferably 1,000 or more and less than 30,000, more preferably 1,500 or more and less than 20,000, and still more preferably 2,000 or more and less than 10,000. When the weight average molecular weight is 30,000 or more, the effect of improving the adhesive force may not be sufficiently obtained in some cases. Moreover, if it is less than 1,000, it will become a low molecular weight, and may cause a fall of adhesive force or a retention characteristic. In the present invention, the measurement of the weight average molecular weight of the (meth) acrylic oligomer can be determined by polystyrene conversion by the GPC method.

Examples of the monomer constituting the (meth) acrylic oligomer include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and (meth) acrylic acid. Isopropyl ester, butyl (meth) acrylate, isobutyl (meth) acrylate, second butyl (meth) acrylate, third butyl (meth) acrylate, amyl (meth) acrylate, ( Isoamyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isopropyl (meth) acrylate Octyl ester, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, (formyl) (Meth) acrylate alkyl (meth) acrylate; such as cyclohexyl (meth) acrylate, isomethacrylate (meth) acrylate, (meth) acrylate dicyclopentyl Ester of acrylic acid and alicyclic alcohol; such as phenyl (meth) acrylate, aryl (meth) acrylate of benzyl (meth) acrylate; (meth) acrylate obtained from terpene compound derivative alcohol, etc. . Such (meth) acrylates can be used alone or in combination of two or more.

As the (meth) acrylic oligomer, an alkyl (meth) acrylate containing a branched structure in an alkyl group such as isobutyl (meth) acrylate or third butyl (meth) acrylate is preferred. ; Such as cyclohexyl (meth) acrylate or isomethacrylate (meth) acrylate, (meth) acrylic acid dicyclopentyl ester (meth) acrylic acid and alicyclic alcohol ester; such as (meth) acrylic acid benzene Ester or benzyl (meth) acrylate, aryl (meth) acrylate, and other (meth) acrylic acid esters having a cyclic structure such as benzyl (meth) acrylate have a relatively bulky acrylic monomer as a monomer unit. By having such a fluffy structure in the (meth) acrylic oligomer, the adhesiveness of the adhesive layer can be further improved. Especially in terms of fluffiness, the effect is higher for those having a ring structure, and the effect is higher for those having a plurality of rings. In addition, in the case where ultraviolet light is used in the synthesis of a (meth) acrylic oligomer or in the preparation of an adhesive layer, it is difficult to cause polymerization inhibition, preferably a saturated bond is used, and it can be used preferably. As the monomer constituting the (meth) acrylic oligomer, an alkyl (meth) acrylate having an alkyl group having a branched structure or an ester with an alicyclic alcohol is used.

In this regard, examples of preferred (meth) acrylic oligomers include copolymers of cyclohexyl methacrylate (CHMA) and isobutyl methacrylate (IBMA), and cyclohexyl methacrylate. Ester (CHMA) and isomethacrylate (IBXMA) copolymer, cyclohexyl methacrylate (CHMA) and acryloline (ACMO) copolymer, cyclohexyl methacrylate (CHMA) and diethyl Copolymer of methacrylamide (DEAA), copolymer of 1-adamantyl acrylate (ADA) and methyl methacrylate (MMA), dicyclopentyl methacrylate (DCPMA) and isomethacrylate ( (IBXMA) copolymer, dicyclopentyl methacrylate (DCPMA), cyclohexyl methacrylate (CHMA), isomethacrylate (IBXMA), isoacrylate (IBXA), cyclopentyl methacrylate (DCPMA ) Copolymers with methyl methacrylate (MMA), dicyclopentyl acrylate (DCPA), 1-adamantyl methacrylate (ADMA), 1-adamantyl acrylate (ADA) each homopolymer Wait.

When the (meth) acrylic oligomer is used in the adhesive composition, the blending amount is not particularly limited, and it is preferably 10 weight based on 100 parts by weight of the (meth) acrylic polymer. It is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, and even more preferably 1 to 3 parts by weight. When the compounding quantity of the said (meth) acrylic-type oligomer exceeds 10 weight part, an elastic modulus will become high, and there exists a trouble that adhesiveness at low temperature may worsen.

The adhesive composition forming the adhesive layer of the present invention may further contain a solvent. Examples of the solvent include solvents used in the solution polymerization method. The solvent in the adhesive composition forming the adhesive layer of the present invention may be the same as or different from the solvent used in the solution polymerization method. The solvent in the adhesive composition forming the adhesive layer of the present invention may be used alone, or two or more solvents may be used in combination.

Furthermore, other well-known additives can be contained in the said adhesive composition in the range which can satisfy characteristics, such as pollution resistance, for example, it can add suitably according to the use use: powders, such as a colorant, a pigment, a surfactant, and a plasticizer , Adhesion-imparting agents, low-molecular-weight polymers, surface lubricants, leveling agents, antioxidants, corrosion inhibitors, light stabilizers, ultraviolet absorbers, polymerization inhibitors, silane coupling agents, inorganic or organic fillers, metal powders, Particles, foils, etc.

＜ Adhesive layer, surface protection film ＞
The surface protection film of the present invention is characterized in that it is provided with a substrate film containing a resin material, the above-mentioned adhesive layer on one side of the above-mentioned substrate film, and the opposite surface of the above-mentioned substrate film having the above-mentioned adhesive layer The above-mentioned antistatic layer containing an antistatic component, and a release film (antistatic layer / base film / adhesive layer / release film) on the side opposite to the side of the above-mentioned base film having the above-mentioned base film. . Further, it is preferable to further include the antistatic layer (antistatic layer / base film / antistatic layer / adhesive layer / release film) between the base film and the adhesive layer. In addition, the above-mentioned adhesive layer is formed by crosslinking of the adhesive composition, and is usually performed after the application of the adhesive composition. However, the adhesive layer containing the crosslinked adhesive composition may be transferred to a substrate film or the like.

The method for forming the adhesive layer on the antistatic layer is not limited. For example, it can be formed by applying the above-mentioned antistatic agent composition (solution) to a substrate film, drying and removing a polymerization solvent, and the like. An antistatic layer is formed on the material film, and an adhesive composition is coated on the produced antistatic layer and dried. Alternatively, as another method, it may be formed by applying the antistatic agent composition (solution) to a substrate film, drying and removing a polymerization solvent, etc., and forming an antistatic layer on the substrate film. The adhesive composition is coated on a release film and dried to form an adhesive layer, and the adhesive layer is transferred to an antistatic layer.

As a method for forming the adhesive layer when the surface protective film of the present invention is produced, a known method used in the production of an adhesive tape can be used. Specific examples include extrusion coating methods such as roll coating, gravure coating, reverse coating, roll brush coating, spray coating, air knife coating, and die coating.

The thickness of the adhesive layer is preferably 3 to 100 μm, more preferably 5 to 50 μm, and still more preferably 5 to 30 μm. If the thickness of the adhesive layer is within the above range, it is easy to obtain a moderate balance between re-peelability and adhesiveness, so it is preferable. On the other hand, in the case of being thicker than the above range, pollution is liable to occur, and in the case of thinner, the cooperating property is poor and unsatisfactory.

The thickness (total thickness) of the surface protective film of the present invention is preferably 10 to 400 μm, more preferably 12 to 200 μm, and even more preferably 15 to 100 μm. If it is in the said range, it will be excellent in adhesive characteristics (removability, adhesiveness, etc.), workability, and an external appearance characteristic. In addition, the said total thickness means the total thickness of all layers including a base film, an adhesive layer, and an antistatic layer.

＜ Release film ＞
In the surface protective film of the present invention, in order to protect the adhesive surface of the adhesive layer, a release film is provided on the opposite side of the surface of the adhesive layer having the substrate film, and the release treated surface of the release film has the characteristics It does not contain polysiloxane. In addition, the "non-polysilicone component" means that it does not contain substantially, and the silicon (Si) element ratio of the release process surface of a release film is 0.5 atomic% or less. Examples of the "polysiloxane component" include polydimethylsiloxane. Moreover, the element ratio of silicon (Si) is based on the atomic ratio (atomic) of silicon atoms (Si) on the release-treated surface (release layer surface) of the release film based on the measurement by X-ray photoelectron spectroscopy. %). The measurement device and measurement conditions are shown below.
Measuring device: PHI Quantera SXM made by ULVAC PHI
X-ray source: monochrome AlKα
XRay Setting: 100 μmf [15 kV, 25 W]
Photoelectron grazing angle: 45 ° relative to the sample surface

The release film (separator) is usually a substrate having a release layer formed using the release agent composition. As a material constituting the above-mentioned substrate, there is paper or a plastic film, and a plastic film can be preferably used in terms of excellent surface smoothness. The film is not particularly limited as long as it can protect the adhesive layer, and examples thereof include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, and a polymethylpentene film. , Polyvinyl chloride film, Vinyl chloride copolymer film, Polyethylene terephthalate (PET) film, Polybutylene terephthalate film, Polyurethane film, Ethylene-vinyl acetate copolymer Films and the like are particularly preferred in terms of transparency or price in terms of polyethylene terephthalate (PET) films.

The release treatment surface of the release film is characterized in that it does not contain a polysiloxane component, and it is preferable that the release film as a whole does not contain a polysiloxane component. By preventing the release treatment surface of the release film from containing a polysiloxane component, it is possible to prevent the use of polyethylene terephthalate (PET) due to additives contained in the base film or the base film. The pollution caused by the produced PET oligomers becomes a better aspect. The detailed reason for preventing (controlling) the contamination of the adherend caused by the PET oligomer contained in the base film by not containing a polysiloxane component is not clear, and the polysiloxane component is contained. When the release treatment surface of the component release film is in contact with the adhesive layer, the PET oligomer contained in the base film may migrate (precipitate) to the interface between the surface of the adhesive layer and the release film to The phenomenon of the surface of the adhesive layer, but when the release treatment surface does not contain a polysiloxane component, the migration (precipitation) to the surface of the adhesive layer is not seen (not recognized), even if it is peeled off. When the surface of the adhesive layer of the surface protective film of the mold film is adhered to the adherend, it will not pollute the adherend, so it becomes a better aspect. In order to exert the peeling property, the release treatment surface of the release film may be subjected to a release treatment using a fluorine-based, long-chain alkyl-based, fatty amidoamine-based release agent, silicon dioxide powder, or the like. Also, antifouling treatment, antistatic treatment such as coating type, kneading type, vapor deposition type, or other antifouling treatment may be performed as needed.

The method for forming a release layer on a substrate is not limited. For example, it can be prepared by applying a solution of a release agent composition to a substrate, and drying and removing a polymerization solvent to form a release layer on the substrate. . Thereafter, curing can be performed for the purpose of adjusting the composition of the release layer. When the release agent composition is coated on a substrate to prepare a release layer, one or more solvents other than a polymerization solvent may be newly added to the release agent composition in a manner capable of being uniformly coated on the substrate. .

As a method for forming the release layer, a known method used in the production of a release layer can be used. Specific examples include extrusion coating methods such as roll coating, gravure coating, reverse coating, roll brush coating, spray coating, air knife coating, and die coating.

The thickness of the release film is usually 5 to 200 μm, and preferably about 10 to 100 μm. If it is in the said range, since it is excellent in the adhesiveness property with respect to an adhesive layer, and peeling workability from a self-adhesive layer, it is preferable.

The surface protection film disclosed herein can also be implemented in the form of including other layers in addition to the base film, the adhesive layer, the antistatic layer, and the release film. Examples of the arrangement of the “other layer” include a substrate film and an antistatic layer.

＜ Optical member ＞
The optical member of the present invention is preferably protected by the surface protective film. The surface protection film has an antistatic adhesive layer or an antistatic layer, which is excellent in antistatic peeling, and the release treatment surface of the release film does not contain a polysiloxane component, so it has excellent pollution resistance and surface protection. The curling of the film is suppressed, and therefore it is not peeled off during processing, transportation, shipment inspection, etc., and can protect the surface of the above-mentioned optical member (polarizing plate, etc.) from damage or contamination, and is useful. In particular, it can be used for plastic products that are prone to generate static electricity. Therefore, in the technical field related to optical and electronic parts where electrification becomes a serious problem, antistatic applications have become very useful.

＜ Display device ＞
The display device of the present invention is preferably protected by the surface protective film. The surface protection film has an antistatic adhesive layer or an antistatic layer, which is excellent in antistatic peeling, and the release treatment surface of the release film does not contain a polysiloxane component, so it has excellent pollution resistance and surface protection. The curling of the film itself is suppressed, so that it does not peel off during processing, transportation, shipment inspection, etc., and can protect the display device from damage or contamination, and is useful. In particular, it can be used for plastic products that are prone to generate static electricity. Therefore, in the technical field related to optical and electronic parts where electrification becomes a serious problem, antistatic applications have become very useful.
[Example]

Hereinafter, several embodiments related to the present invention will be described, but the present invention is not limited to those shown in the specific examples. In addition, "part" and "%" in the following description are based on weight unless otherwise specified. In addition, the formulation amount (use amount) in the table indicates a solid content component, a solid content component ratio, or an effective component.

In addition, each characteristic in the following description is measured or evaluated as follows.

<Measurement of glass transition temperature (Tg)>
The glass transition temperature Tg (° C) is a glass transition temperature Tgn (° C) of a homopolymer formed of each monomer, and is obtained by the following formula using the following literature values.
Formula: 1 / (Tg + 273) = Σ [Wn / (Tgn + 273)]
In the formula, Tg (° C) represents the glass transition temperature of the copolymer, Wn (-) represents the weight fraction of each monomer, Tgn (° C) represents the glass transition temperature of the homopolymer formed by each monomer, and n represents each The type of monomer.
Literature value:
2-ethylhexyl acrylate (2EHA): -70 ° C
4-Hydroxybutyl acrylate (HBA): -32 ° C
Acrylic (AA): 106 ° C

<Measurement of weight average molecular weight (Mw)>
The weight average molecular weight (Mw) was measured using a GPC device (HLC-8220GPC) manufactured by Tosoh Corporation. The measurement conditions are as follows.
Sample concentration: 0.2% by weight (THF solution)
Sample injection volume: 10 μl
Eluent: THF
Flow rate: 0.6 ml / min
Measurement temperature: 40 ° C
Tubing:
Sample column: TSKguardcolumn SuperHZ-H (1) + TSKgel SuperHZM-H (2)
Reference column: TSKgel SuperH-RC (1)
Detector: Differential refractometer (RI)
In addition, a weight average molecular weight is calculated | required by a polystyrene conversion value.

＜ Measurement of Shear Force of Release Film on Surface Protective Film with Release Film ＞
The obtained surface protective film with a release film was cut into a width of 10 mm × 50 mm in length, and a double-sided tape was used on the surface of the release film side of the upper part of the cut sample with a width of 10 mm × 10 mm in length, It was crimped and fixed to an acrylic resin plate (70 mm in length, 100 mm in width, and 1 mm in thickness) as a support by a hand pressure roller.
Next, the upper part of the acrylic resin plate without the surface protective film is clamped by a chuck, and the surface protective film of the release film fixed to the acrylic resin plate with a double-sided tape is used to fix the acrylic resin plate without the surface protective film. Part of the release film is cut and peeled from the surface protection film, and the lower part of the surface protection film in the state where the release film is peeled off is clamped and fixed by a chuck, and the tensile speed is 0.06 m / min in the shearing direction. The maximum value of the shearing force at the time of stretching was taken as the shearing force (N / cm ² ).

The shear force (N / cm ² ) is preferably 15 or more, more preferably 15 to 50, still more preferably 20 to 40, and even more preferably 30 to 50. If the aforementioned shear force is within the above range, for example, it can withstand the force in the shearing direction generated when the surface protective film itself is intended to curl, and the surface protective film does not slip or shift, and the surface protective film can be suppressed from being attached. The curl of the adherend is preferred.

＜ Contamination to glass ＞
The surface protection film was cut into a size of 50 mm in width and 80 mm in length. After peeling the release film attached to the surface of the adhesive layer of the surface protection film, it was attached to the cut with a hand pressure roller to a width of 70 mm and a length of 100. mm glass surface (made by Matsunami Glass), left at 40 ° C × 92% RH for 7 days, peel off the surface protection film, and visually confirm the contamination of the glass surface
(Evaluation criteria)
No pollution: ○
Pollution: ×

＜ Measurement of peeling voltage when peeling release film ＞
The obtained surface protection film with a release film was cut into a size of 50 mm in width and 100 mm in length, and a double-sided adhesive tape was used on the antistatic layer side of the cut surface protection film, and the acrylic film was crimped to acrylic by a hand pressure roller. A resin sheet (ACRYLITE L, manufactured by Mitsubishi Chemical) peeled the release film from the surface of the adhesive layer of the surface protective film at a peeling angle of 150 ° and a peeling speed of 3 m / min. The potential (kV) on the surface of the adhesive layer immediately after peeling was measured using a surface potentiometer (made by Kasuga Electric Corporation, KSD-0103) fixed at a height of 100 mm from the center of the surface protective film. The measurement was performed under the environment of 23 ° C and 50% RH.
In addition, the "antistatic property" of the surface protective film itself was evaluated by "peeling voltage when peeling a release film".

<Measurement of peeling voltage when the surface protective film is peeled off>
The obtained surface-protective film with a release film was cut into a size of 50 mm in width and 110 mm in length. After the release film was peeled off, it was crimped to a previously destaticized glass plate (manufactured by Matsunami Glass, 50 in width) using a hand pressure roller mm, length 100 mm).
After the sample was placed in an environment of 23 ° C. × 50% RH for 1 day, it was set at a specific position on a sample fixing table with a height of 20 mm.
The end of the surface protective film protruding from the glass plate by 10 mm was fixed to an automatic winder, and peeled at a peeling angle of 150 ° and a peeling speed of 10 m / min. The potential (kV) on the surface of the adherend (glass) generated at this time was measured using a surface potentiometer (made by Kasuga Electric Corporation, KSD-0103) fixed at a height of 100 mm from the center of the glass. The measurement was performed under the environment of 23 ° C and 50% RH.
In addition, the "antistatic property (peeling antistatic property)" when the surface protective film was peeled from the adherend was evaluated by "the peeling voltage when the surface protective film was peeled off".

The peeling voltage (kV) (absolute value) when peeling the release film and peeling the surface protective film in the present invention are preferably 0.8 kV or less, more preferably 0.7 kV or less, and even more preferably 0.6 kV or less. If it is in the said range, for example, damage to a liquid crystal driver can be prevented and it becomes a preferable aspect.

＜ Measurement of glass adhesion ＞
The obtained surface-protective film with a release film was cut to a width of 25 mm, and the release film was peeled off. The surface of the adhesive layer of the surface-protective film was bonded to a glass plate (made by Matsunami Glass, with a green edge) using a 2 kg roller. Abrasive, OF1), left as sample for 20 minutes at 23 ° C and 50% relative humidity.
Then, the surface protective film as the above sample was peeled from the glass plate at a speed of 0.3 m / min and an angle of 180 °, and the peeling force of the surface protective film to the glass plate was measured as the adhesive force to the glass (N / 25 mm) .

As the above-mentioned glass adhesion (N / 25 mm), it is preferably 0.01 to 0.5, more preferably 0.02 to 0.4, still more preferably 0.05 to 0.35, even more preferably 0.08 to 0.3, and most preferably 0.09 to 0.2. When the above-mentioned adhesive force to glass is within the above range, for example, peeling does not occur when the surface protective film is attached to an adherend, and the adhesiveness is excellent. In addition, when the surface protective film is peeled and removed, the peelability and peeling work are performed. Excellent performance and become a better appearance.

<Example 1>
[Preparation of (meth) acrylic polymer]
In a four-necked flask equipped with a stirring wing, a thermometer, a nitrogen introduction tube, and a condenser, 100 parts by weight of 2-ethylhexyl acrylate (2EHA), 10 parts by weight of 4-hydroxybutyl acrylate (HBA), and acrylic acid (AA) were added. 0.02 parts by weight, 0.2 parts by weight of 2,2'-azobisisobutyronitrile (AIBN) as a polymerization initiator, and 234 parts by weight of ethyl acetate. Nitrogen was introduced while slowly stirring, and the temperature of the liquid in the flask was maintained at A polymerization reaction was performed at about 65 ° C. for 6 hours to prepare a (meth) acrylic polymer solution (30% by weight). The weight average molecular weight (Mw) of the (meth) acrylic polymer was 650,000, and the glass transition temperature (Tg) was -67.6 ° C.

[Preparation of (meth) acrylic oligomer]
60 parts by weight of dicyclopentanyl methacrylate (DCPMA), 40 parts by weight of methyl methacrylate (MMA), 3.5 parts by weight of α-thioglycerin as a chain transfer agent, and a polymerization solvent 100 parts by weight of toluene was put into a four-necked flask, and this was stirred at 70 ° C. for 1 hour under a nitrogen atmosphere.
Next, 0.2 part by weight of 2,2'-azobisisobutyronitrile as a polymerization initiator was put into a four-necked flask, and reacted at 70 ° C for 2 hours, and then at 80 ° C for 2 hours. Thereafter, the reaction solution was put into a temperature environment of 130 ° C, and toluene, a chain transfer agent and unreacted monomers were removed by drying to obtain a solid (meth) acrylic oligomer. The weight average molecular weight (Mw) of the (meth) acrylic oligomer was 5,100.

[Preparation of acrylic adhesive solution]
The above (meth) acrylic polymer solution (30% by weight) was diluted with ethyl acetate to 20% by weight, and 500 parts by weight of the solution (100 parts by weight of the solid content) was added with an antistatic auxiliary having oxygen 0.225 parts by weight of alkyl polysiloxane (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KF-353), lithium bis (trifluoromethanesulfonyl) fluorenimide, an ionic compound of an antistatic agent (LiTFSI, manufactured by Tokyo Chemical Industry Co., Ltd.) 0.0675 parts by weight (0.0675 parts by weight of solid content), 1.5 parts by weight of the aforementioned acrylic oligomer, and hexamethylene diisocyanate as an aliphatic isocyanate compound as a crosslinking agent 1 part by weight of isocyanurate (manufactured by Tosoh Corporation, Coronate HX: C / HX) (1 part by weight of solid content), and three (acetamidine) iron (manufactured by Nippon Kagaku Kogyo) , Trade name "Nacem Ferric Iron", active ingredient 100% by weight) 0.0075 parts by weight, mixing and stirring to prepare an acrylic adhesive solution (adhesive composition).

[Preparation of aqueous solution for antistatic layer]
A dispersion liquid containing 25% of a polyester resin as a binder (trade name "Vylonal MD-1480", manufactured by Toyobo Co., Ltd., (aqueous dispersion liquid of a saturated copolymerized polyester resin) (binder dispersion liquid)) was prepared. An aqueous dispersion (slip agent dispersion) of carnauba wax (wax ester) as a lubricant was prepared. Furthermore, an aqueous solution (trade name) containing 0.5% of poly (3,4-dioxythiophene) (PEDOT) as a conductive polymer and 0.8% of polystyrene sulfonate (number average molecular weight 150,000) (PSS) was prepared. "Baytron P" (manufactured by HCStark)) (aqueous conductive polymer solution).
To the mixed solvent of water and ethanol, the above-mentioned binder dispersion liquid with a solid content of 100 parts, the above-mentioned lubricant dispersion liquid with a solid content of 30 parts, and a solid content of 50 were added. Parts of the above-mentioned conductive polymer aqueous solution and the melamine-based cross-linking agent were thoroughly mixed by stirring for about 20 minutes. In this way, an aqueous solution (antistatic agent composition) for an antistatic layer having an NV (non-volatile content) of about 0.5% was prepared.

[Preparation of base film with antistatic layer (double-sided)]
As a base film, a transparent polyethylene terephthalate (PET) film (manufactured by Mitsubishi Chemical Co., trade name: T100C50) having a thickness of 50 μm, a width of 30 cm, and a length of 40 cm was prepared. The PET film was coated with the aqueous solution for the antistatic layer by a bar coater, and dried by heating at 130 ° C for 2 minutes. Then, the aqueous solution for the antistatic layer was also coated by a bar coater in the same manner. On the other side of the substrate film, it was dried by heating at 130 ° C for 2 minutes to prepare a substrate film with an antistatic layer (double-sided) having an antistatic layer with a thickness of 30 nm on both sides of the substrate film.

＜ Release film without polysiloxane component ＞
200 parts by weight of xylene (made by Sun Chemical, Xylol) and 600 parts by weight of octadecyl isocyanate (made by OHARA PARAGIUM CHEMICAL Co., Ltd., R-NCO) were added to a reaction vessel equipped with a condenser, while stirring At the time of heating and starting the reflux of xylene, 100 parts by weight of polyvinyl alcohol (Kuraray poval 205, manufactured by Kuraray) was added little by little over 2 hours at 10 minute intervals.
After the completion of the polyvinyl alcohol addition, reflux was performed for 2 hours to complete the reaction. The obtained reaction mixture was cooled to about 80 ° C and then added to methanol. As a result, the reaction product precipitated as a white precipitate. Therefore, the precipitate was separated by filtration, 140 parts by weight of xylene was added, and it was heated to completely dissolve, and then methanol was added again to make it. After precipitating and repeating this operation several times, the precipitate was washed with methanol, and the powder obtained by drying and pulverizing was diluted to 0.3% by weight with water to obtain a release agent composition (solution). This release agent composition was applied to a 25 μm-thick PET film (manufactured by Mitsubishi Chemical, DIAFOIL T100C25) as a base material, and dried at 130 ° C for 1 minute to form a release layer. Release film. In addition, the thickness of the release layer after drying is 20 nm. According to the measurement by X-ray photoelectron spectroscopy, the atomic% of silicon atoms (Si) of the release treatment surface of the release film is lower than ( The detection limit was not reached, and no detection was possible, and it was confirmed that the release-treated surface (substantially) did not contain a polysiloxane component.

[Production of surface protective film]
The above acrylic adhesive solution was coated on the side where the antistatic layer of the base film with the antistatic layer (double-sided) was in contact with the base film, and heated at 130 ° C for 30 seconds to form a 20 μm thick adhesive.剂 层。 The agent layer. Then, the surface of the release film without the polysiloxane component (the release layer side) was bonded to the surface of the adhesive layer to produce a surface protection film (see FIG. 2).

<Examples 2 to 5 and Comparative Examples 1 to 4>
Based on the descriptions in Tables 1 and 2, an adhesive layer, a base film (with an antistatic layer), and a release film were prepared. In addition, regarding the preparation conditions and the like, a surface protection film was finally produced in the same manner as in Example 1. Regarding a substrate film or a release film different from Example 1, the following description was used.

[Preparation of base film with antistatic layer (single-sided)]
In Example 3, a transparent polyethylene terephthalate (PET) film (manufactured by Mitsubishi Chemical Corporation, trade name: T100C38) was prepared as a substrate film having a thickness of 38 μm, a width of 30 cm, and a length of 40 cm. The above-mentioned aqueous solution for the antistatic layer was applied to the PET film with a bar coater, and heated at 130 ° C for 2 minutes to dry it, thereby producing an antistatic layer with a thickness of 10 nm after drying. A base film of an antistatic layer (single-sided) (see FIG. 1).

[Preparation of substrate film without antistatic layer]
In Comparative Example 4, a transparent polyethylene terephthalate (PET) film (manufactured by Mitsubishi Chemical Co., Ltd., trade name: T100C38) was prepared as a substrate film having a thickness of 38 μm, a width of 30 cm, and a length of 40 cm. This PET film was used as a base film without an antistatic layer.

＜ Preparation of release film using polysiloxane component ＞
In Comparative Examples 1 and 2, 100 parts by weight of a polysiloxane release agent (manufactured by Shin-Etsu Chemical Industry Co., Ltd .: KS-847H) and a polysiloxane curing catalyst (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: CAT) were added. -PL-50T) 3.3 parts by weight of toluene (manufactured by Idemitsu Petrochemical Co., Ltd.), hexane (manufactured by Maruzen Petrochemical Co., Ltd., n-hexane), and methyl ethyl ketone (manufactured by Idemitsu Kosan Co., Ltd., MEK) become 1: 2 The mixed solvent with a weight ratio of 1 was diluted to 0.3% by weight to obtain a release agent composition (solution). This release agent composition was applied to a 25 μm-thick PET film (DIAFOIL T100-25, manufactured by Mitsubishi Resin Co., Ltd.) as a substrate, and dried at 130 ° C for 1 minute to prepare a silicone-based release layer. Release film. Furthermore, the thickness of the release layer after drying was 20 nm.

The surface protection films of Examples and Comparative Examples were subjected to the above-mentioned various measurements and evaluations. The results are shown in Table 3.

In the abbreviations in Table 1, "AS-110" used in Example 5 means 1-ethyl-3-methylimidazolium bisfluorosulfonaminium imine [manufactured by Daiichi Kogyo Co., Ltd., a product Name "ELEXCEL AS-110", 100% by weight of active ingredient].

[Table 1]

[Table 2]

[table 3]

From the above evaluation results, it was confirmed that in all the examples, the antifouling, antistatic, peeling antistatic, adhesive, and re-peeling properties were excellent, and the shear force was also excellent, thereby suppressing curling of the surface protective film. . On the other hand, it was confirmed that in Comparative Examples 1 and 2, the release film containing a polysiloxane component was used for the release-treated surface, so that the shearing force or the glass contamination was poor. In addition, it was confirmed that in Comparative Example 3, since the antistatic agent was not used in the adhesive layer, the antistatic property was poor, and in Comparative Example 4, a surface protective film without an antistatic layer was used, so the antistatic property was poor. .
[Industrial availability]

The surface protective film disclosed herein can be preferably used as an optical member such as a polarizing plate, which is a constituent element of a liquid crystal display panel, a plasma display panel (PDP), an organic electroluminescence (EL) display, and the like. , Used to protect the surface protective film of optical components. In particular, it is useful as a surface protection film (optical surface protection film) applied to optical members such as a polarizing plate mounted on a touch panel of an in-cell type or an in-cell type.

1‧‧‧Antistatic layer

1'‧‧‧Antistatic layer

2‧‧‧ substrate film

3‧‧‧ Adhesive layer

4‧‧‧ release film

10‧‧‧ surface protective film

FIG. 1 is a schematic cross-sectional view showing a configuration example of a surface protection film of the present invention.

FIG. 2 is a schematic cross-sectional view showing a configuration example of a surface protection film of the present invention.

Claims (4)

A surface protection film, characterized in that: Substrate film containing resin material, An adhesive layer formed on one side of the substrate film from an adhesive composition containing a (meth) acrylic polymer as a base polymer and an ionic compound as an antistatic component, An antistatic layer containing an antistatic component on the opposite side of the surface of the base film having the adhesive layer, and A release film on the side of the adhesive layer opposite to the side having the substrate film, and The release treatment surface of the release film does not contain a polysiloxane component. The surface protection film according to claim 1, further comprising an antistatic layer containing an antistatic component between the substrate film and the adhesive layer. An optical member characterized by being protected by a surface protective film as claimed in claim 1 or 2. A display device is characterized in that it is protected by a surface protective film as claimed in claim 1 or 2.