TW201817845A - Pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and optical member - Google Patents

Abstract

The present invention provides a pressure-sensitive adhesive composition, a pressure-sensitive adhesive sheet formed using the pressure-sensitive adhesive composition, and an optical member to which the pressure-sensitive adhesive sheet has been applied. The pressure-sensitive adhesive sheet, even after having been applied to an optical member such as a polarizing plate and stored in a high-temperature environment, can achieve the stability over time of antistatic properties and stripping electrification voltage. The pressure-sensitive adhesive composition of the present invention is characterized by comprising a tacky polymer and an ionic-group-containing silicone represented by formula (1). (R1 to R4 may be the same or different and each include any of a C1-10 alkyl group, alkoxy group, aryl group, alicyclic group, fluoroalkyl group, and ionic group, provided that one or more of R1 to R4 include an ionic group; and n is an integer of 0-100.).

Description

Adhesive composition, adhesive sheet and optical member

The present invention relates to an adhesive composition, an adhesive sheet, and an optical member. In particular, the adhesive sheet prepared from the aforementioned adhesive composition can be used in applications such as liquid crystal display panels, plasma display panels (PDP), and organic electroluminescence (EL) displays that are attached to plastic products that are prone to generate static electricity. Etc.), among them, it is especially used as a surface protection film to protect the surface of optical components (such as polarizing plates, wavelength plates, retardation plates, optical compensation films, reflection sheets, brightness enhancement films) used in liquid crystal displays and the like. .

BACKGROUND OF THE INVENTION A surface protection film (also referred to as a surface protection sheet) generally has a structure in which an adhesive layer is provided on a film-like substrate film (support). The protective film is adhered to an adherend (protected body) through the aforementioned adhesive layer, and thus can be used to protect the adhered body from being injured or defaced by processing or transportation. For example, a panel of a liquid crystal display is formed by bonding an optical member such as a polarizing plate or a wavelength plate to a liquid crystal cell through an adhesive layer. In the manufacture of the liquid crystal display panel, a polarizing plate attached to a liquid crystal cell is first manufactured into a tube shape, then rolled out from the tube and cut into a desired size according to the shape of the liquid crystal cell for use. Here, in order to prevent the polarizing plate from being rubbed and injured by a conveying roller or the like in the intermediate step, a countermeasure for bonding a surface protective film on one or both sides (typically, one side) of the polarizing plate is adopted. The surface protection film can be peeled off at an unnecessary stage.

In general, since the surface protection film and the optical member are made of a plastic material, they have high electrical insulation properties and are prone to generate static electricity due to friction or peeling. Therefore, static electricity is also easily generated when the surface protection film is peeled off from an optical member such as a polarizing plate. If a voltage is applied to the liquid crystal in the state where the static electricity is present, the liquid crystal molecules may lose orientation and the panel may be damaged. In addition, the presence of static electricity can also cause dust to attract and reduce workability. Based on the above circumstances, the surface protection film is subjected to antistatic treatment, for example, an antistatic function is provided by forming an antistatic layer on the surface layer (surface coating layer, back surface layer) of the surface protection film or applying antistatic coating (see Patent Documents) 1 and 2).

In order to impart antistatic properties to the adhesive layer itself constituting the surface protective film, the adhesive contains an ionic compound such as an alkali metal salt or an ionic liquid that can exert the function of an antistatic agent (see Patent Document 3).

However, when the surface of the adhesive layer containing an ionic compound is attached to an optical member such as a polarizing plate and stored in a high temperature (warming) environment, the ionic compound will penetrate from the surface of the optical member, resulting in an ionic compound. The reduction of the antistatic energy causes a problem that the optical member cannot be adequately protected. Prior Art Literature Patent Literature

Patent Document 1: Japanese Patent Application Laid-Open No. 2004-223923 Patent Document 2: Japanese Patent Application Laid-Open No. 2008-255332 Patent Literature 3: Japanese Patent Application Laid-Open No. 9-165460

SUMMARY OF THE INVENTION The problem to be solved by the invention Therefore, the present invention has been diligently studied in view of the foregoing circumstances, and an object thereof is to provide an antistatic property and a peeling electrostatic potential that can be achieved even when an optical member such as a polarizing plate is attached and stored in a high temperature environment. A stable adhesive composition, an adhesive sheet formed from the aforementioned adhesive composition, and an optical member to which the aforementioned adhesive sheet is attached.

The means for solving the problem is that the adhesive composition of the present invention is characterized by containing an adhesive polymer and polysiloxane containing an ionic group represented by the following formula (1); [Chemical Formula 1] (R ₁ to R ₄ may be the same or different from each other, and contain any one of an alkyl group, an alkoxy group, an aryl group, an alicyclic group, a fluorine-substituted alkyl group, and an ionic group, and R ₁ 1 or more of ~ R ₄ contains an ionic group; n is an integer from 0 to 100).

The adhesive composition of the present invention preferably contains an oxygen-containing alkylene compound.

The adhesive composition of the present invention preferably contains at least one selected from the group consisting of an acrylic adhesive, a urethane adhesive, and a polysiloxane adhesive.

The adhesive sheet of the present invention preferably has an adhesive layer formed of the aforementioned adhesive composition on at least one side of the substrate film, and the aforementioned adhesive layer has the aforementioned ionic group-containing polysiloxane present on the inside and / or the surface.

In the adhesive sheet of the present invention, it is preferable that a separator is attached to the opposite side of the surface of the adhesive layer that is in contact with the substrate film.

The adhesive sheet of the present invention is preferably a surface of the aforementioned separating member which is in contact with the aforementioned adhesive layer, and the aforementioned polysiloxane containing ionic groups is present.

The optical member of the present invention is preferably attached with the aforementioned adhesive sheet, or an adhesive sheet obtained by peeling the separating member from the aforementioned adhesive sheet. Invention effect

In the present invention, when an adhesive composition containing a specific ionic group-containing polysiloxane is used, an adhesive sheet having an adhesive layer formed of the aforementioned adhesive composition is attached to an optical member such as a polarizing plate even under a high temperature environment. , Still can achieve excellent antistatic properties and the stability of the peeling electrostatic potential, and is useful.

Embodiments for Carrying Out the Invention Embodiments of the present invention will be described in detail below.

<Overall Structure of Adhesive Sheet (Surface Protective Film)> The adhesive sheet disclosed here is generally in the form of an adhesive tape, an adhesive label, an adhesive film, etc., and is particularly suitable for processing or transporting optical components (for example, available When used as an optical member of a liquid crystal display panel such as a polarizing plate or a wavelength plate, a surface protective film for protecting the surface of an optical member. The adhesive layer in the aforementioned surface protection film is typically formed continuously, but is not limited to the above-mentioned form, and may be an adhesive layer formed in a regular or irregular pattern such as a dot shape or a stripe shape. In addition, the surface protection film disclosed herein may be cylindrical or monolithic.

<Base film> The adhesive sheet (surface protection film) of this invention has a base film. The technology disclosed herein can be used without any particular limitation on the resin material constituting the base film, and it is suitable to use, for example, excellent transparency, mechanical strength, thermal stability, moisture blocking properties, directivity, flexibility, etc. Those with dimensional stability and other characteristics. In particular, the base film is flexible, and can be applied by applying an adhesive composition by roll coating or the like and rolling it into a roll.

For the aforementioned substrate film (substrate, support), for example, a resin material composed of the following main resin components (the main component of the resin component, typically 50% by mass or more) can be suitably used. Plastic film as the aforementioned substrate film, namely: polyester polymers such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate; Cellulose polymers such as acetyl cellulose and triethyl cellulose; polycarbonate polymers; acrylic polymers such as polymethyl methacrylate; etc. Other examples of the aforementioned resin materials include styrene polymers such as polystyrene and acrylonitrile-styrene copolymers; polyethylene, polypropylene, polyolefins having a cyclic or norbornene structure, and ethylene-propylene copolymers. And other olefin-based polymers; vinyl chloride-based polymers; nylon 6, nylon 6,6, and aromatic polyamide polymers such as aromatic polyamides; etc. are resin materials. The resin material may be exemplified by fluorene-based polymers, fluorene-based polymers, polyether fluorene-based polymers, polyetheretherketone-based polymers, polyphenylene sulfide-based polymers, vinyl alcohol-based polymers, and chlorine. Vinylidene-based polymers, vinyl butyral-based polymers, aryl ester-based polymers, polyoxymethylene-based polymers, epoxy-based polymers, and the like. It may be a base film made of a mixture of two or more of the above polymers.

As the substrate film, a plastic film made of a transparent thermoplastic resin material can be suitably used. A preferred aspect of the aforementioned plastic film is the use of a polyester film. Here, polyester film refers to a main skeleton based on an ester bond, such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate. Polymer material (polyester resin) is the main resin component. The polyester film has characteristics such as excellent optical characteristics and dimensional stability that are suitable as a substrate film for a surface protection film, but it also has a property of being easily charged with static electricity.

Various kinds of additives such as an antioxidant, an ultraviolet absorber, a plasticizer, and a colorant (pigment, dye, etc.) may be blended in the resin material constituting the aforementioned base film as needed. Further, known or conventional surface treatments such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, acid treatment, alkali treatment, and application of a primer can be performed. The surface treatment may be, for example, a treatment for improving the adhesion between the base film and the adhesive layer (anchorability of the adhesive layer).

The aforementioned base film of the adhesive sheet (surface protection film) of the present invention may also be a plastic film which is subjected to an antistatic treatment. The use of the substrate film is preferable because static electricity of the adhesive sheet itself can be suppressed at the time of peeling. In addition, the base film is a plastic film and an antistatic treatment is performed on the aforementioned plastic film, which can reduce the static electricity of the adhesive sheet itself, and can produce an excellent antistatic energy to the adherend. The method for imparting the antistatic function is not particularly limited, and a conventionally known method may be used. For example, an antistatic resin composed of an antistatic agent and a resin component may be applied, or a conductive polymer or conductive polymer may be applied. A method of conducting a conductive resin, a method of vapor-depositing or plating a conductive substance, or a method of mixing 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 workability for attaching to an adherend and peeling workability from the adherend.

The adhesive sheet disclosed here may be obtained by implementing other layers in addition to the base film and the adhesive layer. The aforementioned other layers may include an undercoat layer (anchoring layer) or the like that can improve the anchoring property of the antistatic layer or the adhesive layer.

<Adhesive composition> The adhesive sheet of the present invention has the aforementioned adhesive layer, and the aforementioned adhesive layer is formed of an adhesive composition. The adhesive composition can be used without particular limitation as long as it has adhesive properties. The adhesive composition may be, for example, an acrylic adhesive, a urethane adhesive, a synthetic rubber adhesive, a natural rubber adhesive, a silicone adhesive, or the like. Among them, an acrylic adhesive is preferred. At least one of the group consisting of an agent, a urethane-based adhesive, and a polysiloxane-based adhesive, and particularly preferably an acrylic adhesive using a (meth) acrylic polymer using an adhesive polymer.

When an acrylic pressure-sensitive adhesive is used for the pressure-sensitive adhesive layer, the (meth) acrylic polymer constituting the pressure-sensitive polymer of the pressure-sensitive acrylic pressure-sensitive adhesive may be a monomer having a carbon number of 1 to 14 Based on the (meth) acrylic monomer as the main monomer. The (meth) acrylic monomer may be used alone or in combination of two or more. By using the aforementioned (meth) acrylic monomer having 1 to 14 carbon atoms, the peeling force (adhesive force) to the adherend (protected body) can be easily controlled to be low, and it can be made light. Adhesive sheet (surface protection film) having excellent peelability and re-peelability. In the present invention, the (meth) acrylic polymer refers to an acrylic polymer and / or a methacrylic polymer, and the (meth) acrylate refers to an acrylate and / or a methacrylate.

Specific examples of the (meth) acrylic monomer having 1 to 14 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, ( Secondary butyl methacrylate, tertiary butyl (meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (formyl) N-octyl acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate Esters, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, and the like.

Among them, when the adhesive sheet of the present invention is used as a surface protection film, n-butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and (meth) ) N-octyl acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate (Meth) acrylic monomers having 4 to 14 alkyl groups, such as n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, and n-tetradecyl (meth) acrylate. In particular, the use of a (meth) acrylic monomer having a carbon number of 4 to 14 can easily control the peeling force (adhesive force) of the adherend to be low, and obtain an excellent re-peelability.

In particular, it is preferably based on 100% by mass of the total monomer components constituting the aforementioned (meth) acrylic polymer, and preferably contains 50% by mass or more of (meth) acrylic monomers having a carbon number of 1 to 14 alkyl groups. It is 80% by mass or more, more preferably 85 to 99.9% by mass, and most preferably 90 to 99% by mass. If it is less than 50% by mass, the moderate wettability of the adhesive composition and the cohesiveness of the adhesive layer will be unfavorable.

In the adhesive composition of the present invention, the (meth) acrylic polymer preferably contains a hydroxyl-containing (meth) acrylic monomer as a raw material monomer. The said hydroxyl-containing (meth) acrylic-type monomer can be used 1 type or 2 or more types. By using the aforementioned hydroxyl-containing (meth) acrylic monomer, it is possible to easily control the cross-linking of the adhesive composition, etc., and it is even possible to easily control the balance between improvement of wettability by flow and reduction in peeling force (adhesive force) during peeling. In addition, the hydroxyl group is different from a carboxyl group or a sulfonate group which can generally function as a cross-linking site, and the hydroxyl group has a moderate interaction with an ionic group-containing polysiloxane or an oxygen-containing alkylene compound of an antistatic component (antistatic agent). Effect, it is also suitable for use in antistatic properties.

Examples of the hydroxy-containing (meth) acrylic monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and (meth) ) 6-hydroxyhexyl acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) Methacrylate, N-hydroxymethyl (meth) acrylamide and the like. In particular, it is preferable to use a hydroxyl-containing (meth) acrylic monomer having an alkyl carbon number of 4 or more to easily achieve light peeling at high-speed peeling, which is preferable.

With respect to 100% by mass of the total monomer components constituting the (meth) acrylic polymer, it is preferable to contain 25% by mass or less of the aforementioned hydroxyl-containing (meth) acrylic monomer, and preferably 20% by mass or less. It is more preferably 0.1 to 15% by mass, and most preferably 1 to 10% by mass. If it is in the said range, it will be easy to control the balance of the wettability of an adhesive composition and the cohesive force of the adhesive layer obtained.

In addition, for the reason that other polymerizable monomer components can easily achieve a balance in adhesive properties, Tg can be 0 ° C or lower (usually -100 ° C or higher), and can be used for adjustment within a range that does not impair the effect of the present invention. Glass transition temperature of (meth) acrylic polymer, peelable polymerizable monomer, etc.

The (meth) acrylic monomer having a large carbon number of 1 to 14 alkyl groups used for the (meth) acrylic polymer and the polymerizable monomer other than the hydroxyl-containing (meth) acrylic monomer can be used. Carboxyl (meth) acrylic monomer. By using the aforementioned carboxyl group-containing (meth) acrylic monomer, it is possible to suppress an increase in adhesion of the pressure-sensitive adhesive sheet (adhesive layer) over time, and to have excellent re-peelability, prevention of increase in adhesion, and workability. The adhesive layer is also excellent in cohesive force and shear force.

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

With respect to 100% by mass of the total monomer components constituting the (meth) acrylic polymer, it is preferable to contain 0 to 5% by mass of the aforementioned carboxyl group-containing (meth) acrylic monomer, and preferably 0 to 3% by mass , More preferably 0 to 2% by mass, and 0 to 0.19% by mass is the best. If it is more than 5% by mass, there will be many acid functional groups such as carboxyl groups having a large polar effect. When the antistatic component is mixed with an ionic group-containing polysiloxane or an oxygen-containing alkylene compound, the aforementioned antistatic component, etc. In this case, ionic conduction is hindered due to the interaction of acid functional groups such as a carboxyl group, which reduces the conduction efficiency, and it is not preferable because sufficient antistatic properties cannot be obtained.

In addition, when the hydroxyl-containing (meth) acrylic monomer and the carboxyl-containing (meth) acrylic monomer are used in combination, it is preferable that the mass of the monomer components constituting the (meth) acrylic polymer is 100% by mass. Contains 0.01 to 0.19% by mass of the carboxyl group-containing (meth) acrylic monomer. By adjusting to the aforementioned range, it is effective to obtain an adhesive composition having excellent re-peelability and preventing increase in adhesion while maintaining antistatic properties.

The (meth) acrylic polymer used for the (meth) acrylic polymer, the (meth) acrylic monomer having 1 to 14 carbons, the hydroxyl-containing (meth) acrylic monomer, and the carboxyl-containing (meth) acrylic The polymerizable monomer other than the monomer can be used without particular limitation as long as it does not impair the characteristics of the present invention. For example, cyano-containing monomers, vinyl ester monomers, aromatic vinyl monomers, and other components that can improve cohesion and heat resistance can be suitably used; fluorene-containing amine monomers, fluorene-containing amine monomers, and amine-containing monomers , Epoxy-containing monomers, N-acrylfluorenyl morpholin, vinyl ether monomers, etc. to improve the peeling force (adhesive force); or a component that has a functional group that can act as a crosslinking point. Among them, nitrogen-containing monomers such as cyano-containing monomers, fluorenimine-containing monomers, fluorenimine-containing monomers, amine-containing monomers, and N-acrylfluorenylmorpholine are preferred. By using a nitrogen-containing monomer, an adhesive sheet (surface protection film) having a moderate peeling force (adhesive force) and an excellent shearing force, which can ensure that embossing or peeling does not occur, is useful. These polymerizable monomers can be used alone or in combination of two or more.

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

Examples of the amidino group-containing monomer include acrylamide, methacrylamide, diethylacrylamide, N-vinylpyrrolidone, N, N-dimethylacrylamide, N, N- Dimethylmethacrylamide, N, N-diethylacrylamide, N, N-diethylmethacrylamide, N, N'-methylenebisacrylamide, N, N- Dimethylaminopropyl acrylamide, N, N-dimethylaminopropylmethacrylamide, diacetone acrylamide, and the like.

Examples of the fluorenimine group-containing monomer include cyclohexylmaleimide, isopropylmaleimide, N-cyclohexylmaleimide, and ikonimine.

Examples of the amine-containing monomer include aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, and N, N-dimethylaminopropyl (methyl Group) acrylate and the like.

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

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

In the present invention, polymerizable monomers other than (meth) acrylic monomers having 1 to 14 carbon atoms, hydroxyl-containing (meth) acrylic monomers, and carboxyl-containing (meth) acrylic monomers With respect to 100% by mass of the total monomer components constituting the aforementioned (meth) acrylic polymer, it is preferably 0 to 50% by mass, and more preferably 0 to 20% by mass. The aforementioned other polymerizable monomers can be appropriately adjusted in order to obtain desired characteristics.

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 containing the aforementioned alkylene oxide-containing reactive monomer is from the viewpoint of compatibility with the ionic group-containing polysiloxane of the antistatic component or the oxygen-containing alkylene compound. , Preferably 1 to 40, and preferably 3 to 40, preferably 4 to 35, and particularly preferably 5 to 30. When the average added mole number is 1 or more, the effect of reducing contamination by the adherend (protected body) can be effectively obtained. In addition, when the average addition mole number exceeds 40, the interaction with the ionic group-containing polysiloxane or the oxygen-containing alkylene compound is large, resulting in an increase in the viscosity of the adhesive composition and the tendency to be difficult to apply, so good. In addition, the terminal of the oxyalkylene chain may be a hydroxyl group directly or substituted with another functional group or the like.

The aforementioned alkylene oxide-containing reactive monomer may be used alone or as a mixture of two or more, but the total content is preferably 0 to 20% by mass of the total monomer component of the (meth) acrylic polymer. It is preferably 0 to 10% by mass. When the content of the alkylene oxide-containing reactive monomer is more than 20% by mass, the interaction with the ionic group-containing polysiloxane or the oxygen-containing alkylene compound may hinder ion conduction and reduce the antistatic property, which is not preferable. .

The oxyalkylene unit containing the aforementioned alkylene oxide-reactive monomer may have a carbon number of 1 to 6, for example, oxymethylene, oxyethyl, oxypropyl, and oxybutyl Wait. The hydrocarbon group of the oxyalkylene chain may be straight or branched.

The aforementioned alkylene oxide-containing reactive monomer is preferably a reactive monomer having an ethylene oxide group. By using a (meth) acrylic polymer containing a reactive monomer having an ethylene oxide group as a base polymer, the base polymer and the polysiloxane containing an ionic group or an alkylene compound containing oxygen can be enhanced. The compatibility is suitable for suppressing the exudation of the adherend, and a low-contamination adhesive composition can be obtained.

The alkylene oxide-containing reactive monomer may be, for example, a (meth) acrylic acid alkylene oxide adduct or a reactive interface having a reactive substituent such as acrylfluorenyl, methacrylfluorenyl, or allyl in the molecule. Active agent etc.

Specific examples of the (meth) acrylic acid alkylene oxide adduct include, for example, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, and polyethylene glycol-polypropylene glycol (meth) acrylic acid. Ester, polyethylene glycol-polybutylene glycol (meth) acrylate, polypropylene glycol-polybutylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, ethoxypoly Ethylene glycol (meth) acrylate, butoxy polyethylene glycol (meth) acrylate, octyloxy polyethylene glycol (meth) acrylate, dodecyl polyethylene glycol (meth) Acrylate, stearyloxypolyethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, octyloxyethylene Alcohol-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 reactive surfactant. Agent.

The weight average molecular weight (Mw) of the aforementioned (meth) acrylic polymer is preferably 100,000 to 5 million, and preferably 200,000 to 4 million, more preferably 300,000 to 3 million, and most preferably 300,000 to 95 Million. When the weight-average molecular weight is less than 100,000, the cohesive force of the adhesive layer becomes small, and the adhesive tends to remain. On the other hand, if the weight-average molecular weight exceeds 5 million, the fluidity of the polymer is reduced, and the wettability of the adherend (for example, a polarizing plate) is insufficient, which may cause the adherend and the adhesive sheet (surface protection film). There is a tendency for the cause of the bulge to occur between the adhesive layers. The weight average molecular weight is measured by GPC (gel permeation chromatography).

The glass transition temperature (Tg) of the (meth) acrylic polymer is preferably 0 ° C or lower, and preferably -10 ° C or lower (normally -100 ° C or higher). If the glass transition temperature is higher than 0 ° C, the polymer will not flow easily, for example, the wettability of the polarizing plate of the optical member is insufficient, which may cause a bump between the polarizing plate and the adhesive layer of the adhesive sheet (surface protection film). Propensity. In particular, by setting the glass transition temperature to -61 ° C or lower, an adhesive layer having excellent wettability and light peelability to a polarizing plate can be easily produced. The glass transition temperature of the (meth) acrylic polymer can be adjusted within the aforementioned range by appropriately changing the monomer component or composition ratio.

The polymerization method of the (meth) acrylic polymer is not particularly limited, and it can be polymerized by known methods such as solution polymerization, emulsion polymerization, block polymerization, and suspension polymerization. In terms of characteristics such as low pollution of the protected object, solution polymerization is preferred. In addition, the obtained polymer may be a random copolymer, a block copolymer, an interpolymer, a graft copolymer, or the like.

When a urethane-based adhesive is used in the adhesive layer, any appropriate urethane-based adhesive may be used. The urethane-based adhesive preferably includes an urethane-based polymer obtained by reacting a polyol and a polyisocyanate compound to obtain an adhesive polymer. Examples of the polyol include polyether polyol, polyester polyol, polycarbonate polyol, and polycaprolactone polyol. Examples of the polyisocyanate compound include diphenylmethane diisocyanate, toluene diisocyanate, and hexamethylene diisocyanate.

When a silicone adhesive is used for the aforementioned adhesive layer, any appropriate silicone adhesive may be used. The polysiloxane adhesive is preferably prepared by mixing or agglomerating a polysiloxane polymer of an adhesive polymer.

The polysiloxane-based adhesive may be an addition reaction-hardening polysiloxane-based adhesive or a peroxide-hardening polysiloxane-based adhesive. Among these polysiloxane adhesives, since no peroxide (such as benzamyl peroxide) is used and no decomposition products are generated, they are preferably addition reaction-hardening polysiloxane adhesives.

For the curing reaction of the addition reaction-hardening polysiloxane adhesive, for example, when a polyalkyl polysiloxane adhesive is to be prepared, a platinum catalyst is generally used to harden the polyalkyl hydrosiloxane composition. Method.

<Ionic group-containing polysiloxane> The adhesive composition of the present invention is characterized by containing an adhesive polymer and an ionic group-containing polysiloxane represented by the following formula (1). Since the aforementioned adhesive composition contains polysiloxane containing ionic groups, the low surface free energy of the polysiloxane chain can be used in a state where the adhesive layer is attached to the surface of the adherend (such as a polarizing plate), even in the state When stored in a high-temperature environment, the aforementioned polysiloxane containing ionic groups does not penetrate into the adherend (from the surface of the adherend to the interior of the adherend), but remains on the surface of the adhesive layer, so even after a period of time The time-stripping electrostatic characteristics are still stable and can maintain the antistatic performance for a long time, which is a better state. In addition, the "internal" of the aforementioned adhesive layer means, for example, when the adhesive layer is formed by using the aforementioned adhesive composition in which the aforementioned ionic group-containing polysiloxane is blended, it means that the adhesive layer is contained in the aforementioned adhesive layer. The "surface" of the aforementioned adhesive layer means, for example, when the adhesive layer is formed by using the aforementioned adhesive composition containing the aforementioned ionic group-containing polysiloxane or not incorporating the aforementioned ionic group-containing polysiloxane. , Means that the surface of the separator to be attached is coated (layered) with the ionic group-containing polysiloxane before the surface of the separator to be attached, and the separator is attached to the adhesive layer before the aforementioned A case where the ionic group-containing polysiloxane is transferred (transferred) from the surface of the separator to the surface of the adhesive layer. [Chemical Formula 2] In addition, R ₁ to R ₄ in the formula (1) may be the same or different from each other, and contain 1 to 10 carbon atoms, an alkoxy group, an aryl group, an alicyclic group, a fluorine-substituted alkyl group, and an ionic group. Either one or more of R ₁ to R ₄ contain an ionic group. n is an integer from 0 to 100.

The ionic group contained in one or more of R ₁ to R ₄ is preferably an ammonium cationic group or an ionic group having a phosphonium cationic group. Among them, one or more of R ₁ to R ₄ are preferably composed of a cationic structure and an anionic component represented by the following formula (a) or (b), or a zwitterionic structure represented by (c) or (d). [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6]

[Chemical Formula 7] R ₅ to R ₇ in the formula (a) may be the same or different from each other, and represent any one of an alkyl group having 1 to 10 carbon atoms, an aryl group, and a fluorine-substituted alkyl group. m is an integer from 1 to 10.

[Chemical Formula 8] R ₈ to R ₁₀ in the formula (b) may be the same or different from each other, and represent any one of an alkyl group having 1 to 10 carbon atoms, an aryl group, and a fluorine-substituted alkyl group. m is an integer from 1 to 10.

One, the anionic component is not particularly limited, such as available ^{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 -, F ( _{HF) n, (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 ^- etc.

[Chemical Formula 9] In the formula (c), R ₁₁ and R ₁₂ may be the same or different from each other, and represent any one of an alkyl group having 1 to 10 carbon atoms, an aryl group, and a fluorine-substituted alkyl group. R ₁₁ and R ₁₂ may form a ring. Represents alkylene. m is an integer from 1 to 10, and p is an integer from 1 to 6.

[Chemical Formula 10] In the formula (d), R ₁₃ and R ₁₄ may be the same or different from each other, and represent any one of an alkyl group having 1 to 10 carbon atoms, an aryl group, and a fluorine-substituted alkyl group. R ₁₃ and R ₁₄ may form a ring. Represents alkylene. m is an integer from 1 to 10, and p is an integer from 1 to 6.

The polysiloxane containing an ionic group contains a polysiloxane chain, so that the low surface free energy of the polysiloxane chain can be used to adhere to the surface of an adherend (such as a polarizing plate) in the state of the adhesive layer, even When stored in a high-temperature environment, the aforementioned ionic group-containing polysiloxane does not penetrate into the adherend (from the surface of the adherend to the interior of the adherend), but remains on the surface of the adhesive layer. The electrostatic property is stable after a period of time, and the antistatic performance can be maintained for a long time. It can be used as an antistatic agent.

Specific examples of the ionic group-containing polysiloxane include, for example, commercially available products X-40-2450 and X-40-2750 (the above are manufactured by Shin-Etsu Chemical Co., Ltd.). These compounds can be used alone or in combination of two or more.

The content of the aforementioned ionic group-containing polysiloxane is relative to the adhesive polymer (the main polymer such as (meth) acrylic polymer, urethane-based polymer, polysiloxane) constituting the aforementioned adhesive composition. 100 parts by mass, preferably 0.01 to 10 parts by mass, preferably 0.02 to 7.5 parts by mass, more preferably 0.03 to 5.5 parts by mass, and most preferably 0.04 to 4.8 parts by mass. Within the above range, even when the adhesive sheet of the present invention is attached to an optical member or the like and stored in a high-temperature environment, the antistatic properties and the stability over time of the peeling electrostatic potential and the light peelability (repeelability) can be satisfied. Is ideal. In addition, in order to satisfy the pollution resistance, it is preferably 0.01 to 5.5 parts by mass with respect to 100 parts by mass of the adhesive polymer.

<Oxylate-containing compound> The adhesive composition of the present invention preferably contains an oxyalkylene-containing compound, which also preferably contains an organopolysiloxane having an oxyalkylene chain, and more preferably contains an oxyalkylene-containing compound. Organic polysiloxane in the main chain. I guess that by using the aforementioned organic polysiloxane, the surface free energy on the surface of the adhesive can be reduced, and light peeling can be achieved.

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 (2). [Chemical Formula 11] In addition, in the formula (2), R ₁ and / or R ₂ has an oxyalkylene chain having 1 to 6 carbon atoms, and the alkylene group in the oxyalkylene chain may be straight or branched. The terminal of the alkylene chain may be an alkoxy group or a hydroxyl group. Either R ₁ or R ₂ may be a hydroxyl group, or an alkyl group or an alkoxy group, and a part of the alkyl group or the alkoxy group may be a functional group in which a hetero atom is substituted. n is an integer from 1 to 300.

The organic polysiloxane is one having a main chain containing a site containing a siloxane (a site of a siloxane), and an end of the main chain having an oxyalkylene chain bonded thereto. I guess that by using the above-mentioned organosiloxane having an oxyalkylene chain, the compatibility with the (meth) acrylic polymer, the antistatic component, and the like can be achieved, and light peeling can be achieved.

Moreover, the said organopolysiloxane of this invention can apply the following structure, for example. Specifically, in the formula, R ₁ and / or R ₂ has an oxyalkylene chain having a carbon number of 1 to 6, and the oxyalkylene chain may be oxymethylene, oxyethyl, or oxypropylene. Base, oxybutyl, etc., among which oxyethyl or oxypropyl is preferred. In addition, when both R ₁ and R ₂ have an oxyalkylene chain, they may be the same or different from each other.

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

Furthermore, the terminus of the oxyalkylene chain may be an alkoxy group or a hydroxyl group, and an alkoxy group is preferred. In order to protect the adhesive surface, when the separator is attached to the surface of the adhesive layer, the organopolysiloxane having a hydroxyl group at the end will interact with the separator, and there is adhesion (peeling) when the separator is peeled from the surface of the adhesive layer. ) Situation of increasing force.

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 aforementioned range, a balance with compatibility with the base polymer can be achieved, which is preferable. Further, the molecule may have a reactive substituent such as a (meth) acrylfluorenyl group, an allyl group, or a hydroxyl group. The organic polysiloxanes may be used alone or as a mixture of two or more.

Specific examples of the aforementioned organic polysiloxane having an oxyalkylene chain in the main chain include, for example, commercially available products under the trade names X-22-4952, X-22-4272, X-22-6266, and KF-6004. KF-889 (the above is manufactured by Shin-Etsu Chemical Industry Co., Ltd.), BY16-211, SF8427 (the above is manufactured by Dow Corning Toray Co., Ltd.), IM22 (made by Asahi Kasei Wacker Corporation), and the like. These compounds can be used alone or in combination of two or more.

Moreover, in addition to the organosiloxane having a (bonded) oxyalkylene chain in the main chain as described above, the organosiloxane having a (bonded) oxyalkylene chain in a side chain can also be used instead of the main The chain is preferably used in an organosiloxane having an oxyalkylene side chain. 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 (3). [Chemical Formula 12] In the formula (3), 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 of 0 to 1,000. However, m and n will not be 0 at the same time. a and b are integers from 0 to 100. However, a and b will not be 0 at the same time. )

Moreover, the said organopolysiloxane of this invention can be used as follows, for example. Specifically, in the formula, R ₁ is a monovalent organic group exemplified by an alkyl group such as methyl, ethyl, and propyl, an aryl group such as phenyl and nitrile, or an aralkyl group such as benzyl and phenethyl, and each It may have a substituent such as a hydroxyl group. As R ₂ , R ₃ and R ₄ , methylene, ethylidene, and propylidene can be used. Here, R ₃ and R ₄ are different alkylene groups, and R ₂ may be the same as or different from R ₃ or R ₄ . In order to increase the concentration of the antistatic component (such as an ionic group-containing polysiloxane) that can be dissolved in the polyoxyalkylene side chain, R ₃ and R ₄ are preferably ethylene or propyl. R ₅ may be a monovalent organic group exemplified by an alkyl group such as a methyl group, an ethyl group, a propyl group, or an fluorenyl group such as an ethyl fluorenyl group or a propyl fluorenyl group, and each may have a substituent such as a hydroxyl group. These compounds may be used alone or in combination of two or more. The molecule may have a reactive substituent such as a (meth) acrylfluorenyl group, an allyl group, or a hydroxyl group. I speculate that among the aforementioned organosiloxanes having a polyoxyalkylene side chain, it is preferable that the organosiloxanes having a polyoxyalkylene side chain having a hydroxyl end are easily compatible with each other.

Specific examples of the aforementioned organosiloxane having an oxyalkylene chain in a side chain include, for example, commercially available product names KF-351A, KF-352A, KF-353, KF-354L, KF-355A, and 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 (The above are 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 (the above are manufactured by Dow Corning Toray Co., Ltd.), TSF-4440, TSF-4441, TSF-4445, TSF-4450, TSF-4446, TSF- 4452, TSF-4460 (manufactured by Momentive Performance Materials), BYK-333, BYK-307, BYK-377, BYK-UV3500, BYK-UV3570 (by BYK JAPAN), and the like. These compounds may be used alone or in combination of two or more.

The HLB (Hydrophile-Lipophile Balance) of the aforementioned organosiloxane used in the present invention is preferably 1 to 16, and more preferably 3 to 14. If HLB 値 is out of the aforementioned range, the contamination of the subject will be poor and unfavorable.

The said adhesive composition may also contain the oxygen-containing alkylene compound which does not contain an organic polysiloxane. Since the adhesive contains the aforementioned compound, an adhesive having better wettability to an adherend can be obtained.

Specific examples of the aforementioned oxygen-containing alkylene compound containing no organic polysiloxane include polyoxyalkylene alkylamine, polyoxyalkylene diamine, polyoxyalkylene fatty acid ester, and polyoxyalkylene. Alkyl sorbitan fatty acid ester, polyoxyalkylene alkylphenyl ether, polyoxyalkylene alkyl ether, polyoxyalkylene alkylallyl ether, polyoxyalkylene alkylphenyl Non-ionic surfactants such as allyl ether; polyoxyalkylene alkyl ether sulfate, polyoxyalkylene alkyl ether phosphate, polyoxyalkylene alkyl phenyl ether sulfate, Anionic surfactants such as polyoxyalkylene alkyl phenyl ether phosphate ester salts; other cationic surfactants or zwitterionic surfactants with polyoxyalkylene chain (polyalkylene oxide chain) can be mentioned , Polyether compounds with polyoxyalkylene chains (and derivatives thereof), acryl compounds with polyoxyalkylene chains (and derivatives thereof), and the like. In addition, a polyoxyalkylene chain-containing monomer may be blended as the 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 (polyether component) having a polyoxyalkylene chain include a block copolymer of polypropylene glycol (PPG) -polyethylene glycol (PEG), and a block of PPG-PEG-PPG. Copolymers, block copolymers of PEG-PPG-PEG, etc. Examples of the derivative of the polyether-based compound having a polyoxyalkylene chain include an oxyalkylene compound (PPG monoalkyl ether, PEG-PPG monoalkyl ether, etc.) whose end is etherified, and whose end is acetamidine. Chemical oxygenated compounds (such as terminal acetylated PPG, etc.).

Specific examples of the acrylfluorenyl compound having a polyoxyalkylene chain include a (meth) acrylate polymer having an oxyalkylene group. The addition mole number of the oxyalkylene unit of the aforementioned oxyalkylene group is preferably from 1 to 50, more preferably from 2 to 30, and even more preferably from 2 to 20 from the viewpoint of coordination with an ionic group-containing polysiloxane. The terminal of the oxyalkylene chain may be a hydroxyl group directly or may be substituted with an alkyl group, a phenyl group, or the like.

The aforementioned (meth) acrylate polymer having an oxyalkylene group is preferably a polymer containing (meth) acrylic acid alkylene oxide as a monomer unit (component), and specific examples of the aforementioned (meth) acrylic acid alkylene oxide Examples of the glycol-containing (meth) acrylate include methoxy-diethylene glycol (meth) acrylate, methoxy-triethylene glycol (meth) acrylate, and the like. Ethoxy-polyethylene glycol such as polyethylene glycol (meth) acrylate type, ethoxy-diethylene glycol (meth) acrylate, ethoxy-triethylene glycol (meth) acrylate (Meth) acrylate type, butoxy-polyethylene glycol (meth) such as butoxy-diethylene glycol (meth) acrylate, butoxy-triethylene glycol (meth) acrylate Acrylate type, phenoxy-diethylene glycol (meth) acrylate, phenoxy-triethylene glycol (meth) acrylate and other phenoxy-polyethylene glycol (meth) acrylate type, Methoxy groups such as 2-ethylhexyl-polyethylene glycol (meth) acrylate, nonylphenol-polyethylene glycol (meth) acrylate type, methoxy-dipropylene glycol (meth) acrylate- Polypropylene glycol (meth) acrylate type and the like.

In addition, as the monomer unit (component), a monomer unit (component) other than the (meth) acrylic acid alkylene oxide may be used. Specific examples of other monomer components include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, secondary butyl (meth) acrylate, and trimethyl (meth) acrylate. Grade butyl, isobutyl (meth) acrylate, 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, (meth) ) Acrylic acid esters and / or methacrylic acid esters having 1 to 14 carbon atoms, such as n-tridecyl acrylate and n-tetradecyl (meth) acrylate.

In addition, as the monomer unit (component) other than the (meth) acrylic acid alkylene oxide, a carboxyl group-containing (meth) acrylate, a phosphate group-containing (meth) acrylate, and a cyano group (meth) may be suitably used. Acrylates, vinyl esters, aromatic vinyl compounds, (meth) acrylates containing anhydride groups, (meth) acrylates containing hydroxyl groups, (meth) acrylates containing amine groups, and (meth) groups containing amine groups Acrylates, epoxy-containing (meth) acrylates, N-propenyl morpholine, vinyl ethers, and the like.

In a preferred aspect, the aforementioned polyoxyalkylene chain-containing compound not containing an organopolysiloxane is a compound having a (poly) ethylene oxide chain at least in part. By blending the aforementioned (poly) ethylene oxide chain-containing compound, the compatibility between the base polymer and the antistatic component can be improved, and the exudation of the adherend can be suitably suppressed to produce a low-contamination adhesive composition. Among them, especially when a block copolymer of PPG-PEG-PPG is used, an adhesive with excellent low pollution can be prepared. The mass of the (poly) ethylene oxide chain-containing compound of the aforementioned polyethylene oxide chain compound as a whole of the aforementioned polyoxyalkylene chain-containing compound containing no organic polysiloxane is preferably 5 to 90% by mass, more preferably 5 to 85% by mass, more preferably 5 to 80% by mass, and most preferably 5 to 75% by mass.

The molecular weight of the aforementioned polyoxyalkylene-containing compound containing no organic polysiloxane is preferably a number average molecular weight (Mn) of 50,000 or less, and preferably 200 to 30,000, more preferably 200 to 10,000, and generally 200 to 10,000. 5000 people. When Mn is much larger than 50,000, the compatibility with the acrylic polymer is reduced, and the adhesive layer tends to be whitened. If Mn is far less than 200, the aforementioned polyoxyalkylene compound may easily cause pollution. The term "Mn" used herein refers to polystyrene-equivalent europium obtained by GPC (gel permeation chromatography).

Specific examples of the commercially available products containing the polyoxyalkylene chain-containing compound containing no organic polysiloxane are, for example, Adeka Pluronic 17R-4, Adeka Pluronic 25R-2 (all of which are manufactured by ADEKA Corporation), and LATEMUL. PD-420, LATEMUL PD-420, LATEMUL PD-450, EMULGEN120 (made by Kao Corporation), Aqualon HS-10, KH-10, NOIGEN EA-87, EA-137, EA-157, EA-167, EA-177 (The above is manufactured by Daiichi Industries Pharmaceutical Co., Ltd.).

Content of the said oxygen-containing alkylene compound with respect to the adhesive polymer (the main polymer which comprises the said adhesive composition, for example, (meth) acrylic-type polymer, urethane-type polymer, polysiloxane Oxygen-based polymer, etc.) 100 parts by mass, preferably 0.01 to 5.0 parts by mass, more preferably 0.02 to 2 parts by mass, more preferably 0.03 to 1.6 parts by mass, and most preferably 0.1 to 0.8 parts by mass. If it is in the said range, it is easy to have both the antistatic property and light peelability (repeelability) of the adhesive sheet of this invention, and it is preferable.

<Crosslinking agent> In the adhesive sheet (surface protection film) of this invention, it is preferable that the said adhesive composition contains a crosslinking agent. In the present invention, an adhesive layer can be formed using the aforementioned adhesive composition. For example, when the pressure-sensitive adhesive composition is an acrylic pressure-sensitive adhesive containing the (meth) acrylic polymer, it is appropriate to adjust the structural unit, the structure ratio, and the selection and addition of the crosslinking agent of the (meth) acrylic polymer. Cross-linking at a ratio, etc., can produce an adhesive sheet (adhesive layer) having more excellent heat resistance.

The crosslinking agent used in the present invention may also be an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative, a metal chelate compound, etc., and an isocyanate compound is particularly 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 diisocyanate, and diisocyanate. Alicyclic isocyanates such as cyclopentyl ester, cyclohexyl diisocyanate, isophorone diisocyanate (IPDI), 1,3-bis (isocyanatomethyl) cyclohexane, 2,4- Aromatic isocyanates such as toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, and dimethyl dimethyl diisocyanate (XDI). Trimeric isocyanate bond, uretdione bond, urea bond, carbodiimide bond, uretonimine bond, two Modified polyisocyanate modifiers such as triketone bonds. For example, commercially available products can be named Takenate 300S, Takenate 500, Takenate 600, Takenate D165N, Takenate D178N (the above is manufactured by Takeda Pharmaceutical Industry Co., Ltd.), sumidur T80, sumidur L, Desmodur N3400 (the above is manufactured by Sumika Bayer Urethane) , Millionate MR, Millionate MT, CoronateL, CoronateHL, CoronateHX (the above are manufactured by Nippon Polyurethane Industry Co., Ltd.) and the like. These isocyanate compounds may be used alone, or two or more of them may be used in combination, or a bifunctional isocyanate compound and a trifunctional or more isocyanate compound may be used in combination. When a cross-linking agent is used in combination, both adhesiveness and repellency (adhesion to curved surfaces) can be used, and an adhesive sheet having more excellent adhesion reliability can be obtained.

When the isocyanate compound (a bifunctional isocyanate compound and a trifunctional or higher isocyanate compound) is used in combination, the blending ratio (mass ratio) of the two compounds is preferably [bifunctional isocyanate compound] / [trifunctional or higher isocyanate compound] (mass Ratio) is 0.1 / 99.9 ~ 50/50 for blending, preferably 0.1 / 99.9 ~ 20/80, and more preferably 0.1 / 99.9 ~ 10/90, more preferably 0.1 / 99.9 ~ 5/95, and 0.1 / 99.9 ~ 1/99 is best. By adjusting the blending within the aforementioned range, an adhesive layer having excellent adhesion and repellency resistance can be obtained, which is a preferable aspect.

Examples of the epoxy compound include N, N, N ', N'-tetraepoxypropyl-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. Examples of the aziridine derivatives include commercially available products under the trade names HDU, TAZM, TAZO (the above are manufactured by Hugo Pharmaceutical Co., Ltd.).

Examples of the metal chelate compound include metal components such as aluminum, iron, tin, titanium, and nickel. The chelate compounds are acetylene, methylacetate, and ethyl lactate.

The content of the crosslinking agent used in the present invention is, for example, preferably from 0.01 to 20 parts by mass relative to 100 parts by mass of the aforementioned (meth) acrylic polymer, and more preferably from 0.1 to 15 parts by mass, and more preferably from 0.5 to 10 parts by mass. 1 to 6 parts by mass are best. If the foregoing content is less than 0.01 parts by mass, the cross-linking formation by the cross-linking agent is insufficient, resulting in a decrease in the cohesive force of the resulting adhesive layer, failing to obtain sufficient heat resistance, and causing a cause of residues. tendency. On the other hand, if the content is more than 20 parts by mass, the cohesion of the polymer will be increased, and the fluidity will be reduced, resulting in insufficient wettability to the adherend (for example, a polarizing plate), which may cause the adherend and the adhesive. There is a tendency for the cause of the bulge to occur between the layers (adhesive composition layer). In addition, a large amount of the crosslinking agent tends to decrease the peeling electrostatic characteristics. These crosslinking agents can be used alone or in combination of two or more.

The adhesive composition may further include a crosslinking catalyst in order to more effectively advance any of the above-mentioned crosslinking reactions. As the cross-linking catalyst, for example, the following catalysts can be used: tin-based catalysts such as dibutyltin dilaurate and dioctyltin dilaurate; iron (acetylacetone), and (hexane-2,4-di) Ketone) iron, ginseng (hepta-2,4-dione) iron, ginseng (hepta-3,5-dione) iron, ginseng (5-methylhexa-2,4-dione) iron, ginseng (octyl -2,4-dione) iron, ginseng (6-methylheptan-2,4-dione) iron, ginseng (2,6-dimethylheptan-3,5-dione) iron, ginseng (nonyl -2,4-dione) iron, ginseng (non-4,6-dione) iron, ginseng (2,2,6,6-tetramethylhepta-3,5-dione) iron, ginseng (ten Trioxane-6,8-dione) iron, ginseng (1-phenylbutane-1,3-diketone) iron, ginseng (hexafluoroacetamidineacetone) iron, ginseng (ethylacetate) iron, ginseng (N-propylacetate) iron, ginseng (isopropylacetate) iron, ginseng (n-butylacetate) iron, ginseng (secondary butylacetate) iron, ginseng (ethylacetate) Grade butyl) iron, ginseng (methyl acetate propyl acetate), ginseng (ethyl acetate propyl) iron, ginseng (n-propyl propyl acetate) iron, ginseng (isopropyl propyl acetate) iron, ginseng ( N-butyl propionate) iron, ginseng (secondary butyl acetate) iron, ginseng (tertiary butyl acetate) iron, ginseng (benzyl acetoacetate) iron, ginseng (dimethyl malonate) ester) Iron-based catalysts such as iron, ginseng (diethyl malonate), trimethoxy iron, triethoxy iron, triisopropoxy iron, and ferric chloride. These crosslinking catalysts may be used alone or in combination of two or more.

The content of the cross-linking catalyst is not particularly limited. For example, it is preferably set to about 0.0001 to 1 part by mass, and more preferably 0.001 to 0.5 part by mass with respect to 100 parts by mass of the (meth) acrylic polymer. If it is within the aforementioned range, the crosslinking reaction speed becomes faster when the adhesive layer is formed, and the storage life of the adhesive composition becomes longer, which is a preferable aspect.

In addition, the adhesive composition may contain a compound that undergoes keto-enol tautomerism. For example, an adhesive composition containing a cross-linking agent or an adhesive composition containing a cross-linking agent can be suitably used in a state containing a compound that undergoes the aforementioned keto-enol tautomerism. Thereby, excessive increase in viscosity and gelation of the adhesive composition can be suppressed after the crosslinking agent is blended, and the effect of extending the storage life of the adhesive composition can be achieved. When at least an isocyanate compound is used as the crosslinking agent, it is particularly meaningful to include a compound that undergoes keto-enol tautomerism. This technique can be applied, for example, when the aforementioned adhesive composition is in the form of an organic solvent solution or a solvent-free form.

As the compound capable of performing the aforementioned keto-enol tautomerism, various β-dicarbonyl compounds can be used. Specific examples include: acetoacetone, 2,4-hexanedione, 3,5-heptanedione, 2-methylhexan-3,5-dione, 6-methylheptan-2,4-dione Β-diketones such as 2,6-dimethylhepta-3,5-dione; methyl ethyl acetate, ethyl ethyl acetate, isopropyl ethyl acetate, tert-butyl ethyl acetate, etc. Acetylacetate; Propylacetate, ethylpropionate, isopropylpropionate, tert-butylpropionate, etc. Propylacetate; isobutylacetate, isobutylacetate Isobutyl acetic acid esters such as ethyl acetate, isobutyl acetic acid isopropyl ester, and tert-butyl isobutyl acetic acid acetate; malonates such as methyl malonate and ethyl malonate. Among the preferred compounds are acetoacetone and acetoacetate. The compounds that undergo keto-enol tautomerism can be used alone or in combination of two or more.

The content of the compound that undergoes keto-enol tautomerism may be, for example, 0.1 to 20 parts by mass with respect to 100 parts by mass of the (meth) acrylic polymer, and usually 0.5 to 15 parts by mass ( For example, 1 to 10 parts by mass) is appropriate. When the amount of the compound is too small, it may be difficult to exhibit a sufficient use effect. On the other hand, when the above-mentioned compound is used too much, the cohesive force may be reduced by remaining in the adhesive layer.

In addition, the aforementioned adhesive composition may also contain other known additives, such as powders such as lubricants, colorants, pigments, plasticizers, tackifiers, low molecular weight polymers, surface lubricants, leveling agents, antioxidants, and Corrosives, light stabilizers, ultraviolet absorbers, anti-polymerization agents, silane coupling agents, inorganic or organic fillers, metal powders, particles, foils, etc. are appropriately added depending on the application.

<Adhesive layer and adhesive sheet (surface protection film)> The adhesive sheet of the present invention is formed by forming the aforementioned adhesive layer on at least one side of a base film. At this time, the cross-linking of the adhesive composition is generally applied to a coating. Cloth adhesive composition is carried out, however, an adhesive layer composed of a crosslinked adhesive composition may be transferred onto a substrate film or the like.

The method for forming the adhesive layer on the base film is not particularly limited. For example, after the aforementioned adhesive composition (solution) is applied to the base film, the polymerization solvent is dried and removed to form the adhesive layer. Made on a base film. After that, maintenance can also be performed to adjust the component transfer of the adhesive layer or adjust the crosslinking reaction. When an adhesive composition is coated on a base film to prepare an adhesive sheet, one or more solvents other than a polymerization solvent may be added to the adhesive composition in order to allow uniform coating on the base film.

In addition, as a method for forming the adhesive layer when producing the adhesive sheet of the present invention, a known method for producing adhesive tapes can be used. Specific examples include roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating, and extrusion coating using die coating and the like.

The adhesive sheet of the present invention is generally made into a thickness of the aforementioned adhesive layer of 3 to 100 μm, and preferably about 5 to 50 μm. If the thickness of the adhesive layer is within the aforementioned range, it is preferable to obtain a moderate balance between re-peelability and adhesion.

In addition, the total thickness of the adhesive sheet of the present invention is preferably 8 to 300 μm, more preferably 10 to 200 μm, and most preferably 20 to 100 μm. If it is within the aforementioned range, the adhesive properties (re-peelability, adhesiveness, etc.), workability, and appearance characteristics are excellent, which is a preferable aspect. In addition, the said total thickness means the total thickness of all layers including a base film, an adhesive layer, and other layers.

<Separator> In the pressure-sensitive adhesive sheet of the present invention, a separator is preferably attached on the opposite side of the surface of the adhesive layer that is in contact with the substrate film. The separator can be adhered to the surface of the adhesive layer in order to protect the adhesive surface as needed.

Paper or a plastic film is used as a material constituting the separator, and a plastic film is suitable from the viewpoint of excellent surface smoothness. The thickness of the adhesive layer is not particularly limited, and examples thereof include polyethylene films, polypropylene films, polybutene films, polybutadiene films, polymethylpentene films, polyvinyl chloride films, Vinyl chloride copolymer film, polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, ethylene-vinyl acetate copolymer film, etc.

The thickness of the separator 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 the peeling workability by the self-adhesive layer, it is preferable. In the aforementioned separator, a release agent using polysiloxane, fluorine-based, long-chain alkyl-based, or fatty acid ammonium-based may be used as required, and release and antifouling treatments may be performed using silica powder or the like, or coating may be performed. Type, kneading type, evaporation type and other antistatic treatment.

In the adhesive sheet of the present invention, the surface of the separator in contact with the adhesive layer is preferably present (coated) with the ionic group-containing polysiloxane (see FIG. 1). The ionic group-containing polysiloxane exists on the surface of the separator in contact with the adhesive layer (coated, that is, a coating film is formed), and when the separator is attached to the adhesive layer, The ionic group-containing polysiloxane is transferred (transferred) from the surface of the separator to the surface of the adhesive layer, and in a state where the adhesive layer is attached to the surface of the adherend (for example, a polarizing plate), Under high temperature environment, the aforementioned polysiloxane containing ionic groups will not penetrate into the adherend (from the surface of the adherend to the interior of the adherend), so the electrostatic characteristics are stable even after a period of time, and the resistance can be maintained for a long time. Static performance is better.

<Optical member> The optical member of the present invention is preferably attached (protected) using the aforementioned adhesive sheet. The aforementioned adhesive sheet has excellent antistatic properties and lasting stability of the peeling electrostatic potential, so it can be used for surface protection (surface protection film) such as processing, transportation, and shipping, and can be used to protect the aforementioned optical components (polarizing plates, etc.) ) Surface. In particular, it can be used for plastic products that are prone to generate static electricity. In the field of optical and electronic components related to static electricity, which is a serious problem, it is very useful for antistatic applications. Examples

Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the specific examples shown. In addition, "parts" and "%" in the following descriptions indicate quality standards unless otherwise specified. The blending amount (addition amount) in the table is shown.

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

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

<Measurement of initial peeling electrostatic potential> Each of the adhesive sheets was cut into a width of 70 mm and a length of 130 mm, and the release liner was peeled off. Then, a polarizing plate (manufactured by Nitto Denko Corporation, SEG1423DU polarizing plate, and width: 70 mm) was attached to a glass plate. (Length: 100mm), so that one end of the adhesive sheet is more than 30mm away from one end of the polarizing plate and press-attached with a manual roller. After the sample was left to stand in an environment of 23 ° C. × 50% RH for one day, as shown in FIG. 2, it was mounted on a predetermined position of a sample fixing table 30 having a height of 20 mm. The end of the adhesive sheet (surface protection film) 1 that was 30 mm more from the polarizing plate 20 was fixed to an automatic winder (not shown), and peeled at a peeling angle of 150 ° and a peeling speed of 30 m / min. A potentiometer 40 (manufactured by SHISHIDO ELECTROSTATIC, LTD., Type "STATIRON DZ-4") fixed at a position 30 mm in height from the center of the polarizing plate 20 was used to measure the surface potential of the adherend (polarizing plate) at this time. "Initial peeling electrostatic potential". The measurement was performed under the environment of 23 ° C and 50% RH.

<Measurement of peeling electrostatic potential stored at 70 ° C.> Each of the adhesive sheets was cut into a width of 70 mm and a length of 130 mm, and the release liner was peeled off. Then, a polarizing plate (manufactured by Nitto Denko Corporation, SEG1423DU polarized light) was bonded to a glass plate. Plate, width: 70mm, length: 100mm), so that one end of the adhesive sheet is more than 30mm away from one end of the polarizing plate and press-attached with a manual roller. After the sample was left in an environment at 70 ° C. for 120 hours, as shown in FIG. 2, it was mounted on a predetermined position of a sample fixing table 30 having a height of 20 mm. The end of the adhesive sheet (surface protection film) 1 which was 30 mm more from the polarizing plate 20 was fixed to an automatic winder (not shown), and peeled at a peeling angle of 150 ° and a peeling speed of 30 m / min. A potentiometer 40 (manufactured by SHISHIDO ELECTROSTATIC, LTD., Type "STATIRON DZ-4") fixed at a height of 30 mm from the center of the polarizing plate 20 was used to measure the surface potential of the adherend (polarizing plate) at this time. "Peel electrostatic potential stored at 70 ° C". The measurement was performed under the environment of 23 ° C and 50% RH.

In addition, the initial peeling electrostatic potential and the peeling electrostatic potential (kV) (absolute 値) stored at 70 ° C of the present invention are preferably 0.55 or less, more preferably 0.5 or less, and still more preferably 0.45 or less. If it is within the foregoing range, the adhesive sheet that is peeled off after initial and 120 hours storage at 70 ° C will not generate static electricity, but has excellent antistatic properties, time-dependent peeling electrostatic properties, and excellent workability, which is preferred. Appearance.

<Presence or absence of pollution (pollution resistance)> Each of the adhesive sheets was cut to a width of 50 mm and a length of 80 mm, and the separator was peeled off, and then a TAC polarizing plate (manufactured by Nitto Denko Corporation, SEG1423DU polarizing plate, width: 70 mm, length: 100 mm) The sample was evaluated by adding air bubbles while pressing with a manual roller. After the evaluation sample was left for 120 hours in a 70 ° C environment, the adhesive sheet was peeled from the adherend by hand, and the traces of bubbles on the surface of the adherend at this time were visually observed. In addition, no bubble trace was evaluated as ○, and a bubble trace was observed as ×.

<Preparation of acrylic polymer (1)> A four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a cooler was fed with 96 parts by mass of 2-ethylhexyl acrylate (2EHA) and 2-hydroxyethyl acrylate. After 4 parts by mass of an ester (HEA), 0.2 parts by mass of 2.2′-azobisisobutyronitrile as a polymerization initiator, and 150 parts by mass of ethyl acetate, nitrogen gas was introduced while slowly stirring, and the temperature of the liquid in the flask was The polymerization reaction was performed while maintaining the temperature at about 65 ° C. for 6 hours to prepare a solution (40% by mass) of the acrylic polymer (1). The weight average molecular weight (Mw) of the acrylic polymer (1) was 540,000.

<Preparation of acrylic polymer (2)> A four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a cooler was charged with 91 parts by mass of 2-ethylhexyl acrylate (2EHA) and 4-hydroxybutyl acrylate. After 9 parts by mass of ester (4HBA), 0.02 parts by mass of acrylic acid (AA), 0.2 parts by mass of 2.2′-azobisisobutyronitrile as polymerization initiator, and 150 parts by mass of ethyl acetate, nitrogen was introduced while slowly stirring. Then, the temperature of the liquid in the flask was maintained at about 65 ° C. for 6 hours to perform a polymerization reaction to prepare a solution (40% by mass) of the acrylic polymer (2). The weight average molecular weight (Mw) of the acrylic polymer (2) was 540,000.

<Example 1> [Preparation of acrylic adhesive solution] The acrylic polymer (1) solution (40% by mass) was diluted with ethyl acetate to 20% by mass, and 500 parts by mass of the solution (solid content of 100%) 5 parts by mass (0.5 parts by mass of solid content) of a solution obtained by diluting ionic group-containing polysiloxane (X-40-2450, manufactured by Shin-Etsu Chemical Industry Co., Ltd.) with ethyl acetate to 10% by mass was added. Trifunctional isocyanate compound, trifunctional isocyanate compound, hexamethylene isocyanate, trimeric isocyanate (Coronate HX, manufactured by Tosoh Corporation), 2 parts by mass (2 parts by mass of solid content), and dibutyltin dilaurate as a crosslinking catalyst ( 1% by mass of ethyl acetate solution) 3 parts by mass (0.03 parts by mass of solid content) were mixed and stirred to prepare an acrylic adhesive solution.

[Production of antistatic film] 10 parts by mass of an antistatic agent (manufactured by Solvex Corporation, MICRO-SOLVER RMd-142, the main component being tin oxide and polyester resin) was mixed with 30 parts by mass of water and 70 parts by mass of methanol. The solvent was diluted to prepare an antistatic solution. The prepared antistatic agent solution was coated on a polyethylene terephthalate (PET) film (thickness: 38 μm) with a wire bar, and dried at 130 ° C. for 1 minute to remove the solvent to form an antistatic agent. Layer (thickness: 0.2 μm) while making an antistatic film.

[Production of adhesive sheet (surface protection film)] The above-mentioned acrylic adhesive solution was coated on the surface of the antistatic film opposite to the antistatic surface, and heated at 130 ° C for 2 minutes to form a thickness of 15 μm. Adhesive layer. Next, the surface of the above-mentioned adhesive layer was pasted with a silicone-treated surface of a polyethylene terephthalate film (thickness: 25 μm) on which one surface was subjected to a silicone treatment to form an adhesive sheet.

<Example 2> An acrylic polymer (2) was used in place of the acrylic polymer (1) used in Example 1, and an ionic group-containing polysiloxane X-40-2750 was used instead of the ionic group-containing polysiloxane X-40-2750. Except for -40-2450, an adhesive sheet was prepared in the same manner as in Example 1.

<Example 3> An acrylic polymer (2) was used in place of the acrylic polymer (1) used in Example 1, and 0.5 part by mass of an organopolysiloxane-containing oxyalkylene compound KF353 (Shin-Etsu Chemical Co., Ltd.) was added. Production), and then an adhesive sheet was produced in the same manner as in Example 1.

<Example 4> The acrylic polymer (2) was used in place of the acrylic polymer (1) used in Example 1, and 0.2 parts by mass of LATEMUL PD- 420 (manufactured by Kao Corporation), and then an adhesive sheet was produced in the same manner as in Example 1.

<Examples 5 to 7> The acrylic polymer (2) was used instead of the acrylic polymer (1) used in Example 1, and the amount of X-40-2450 added in the table was added. Way to make an adhesive sheet.

<Example 8> [Preparation of urethane-based adhesive solution] 85 parts by mass of a polyol based on PREMINOL S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000) and a polyol having 3 hydroxyl groups 13 parts by mass of SANNIX GP3000 (manufactured by Sanyo Kasei Co., Ltd., Mn = 3000), 3 parts by mass of SANNIX GP1000 (manufactured by Sanyo Kasei Co., Ltd., Mn = 1000), 2 parts by mass of a cross-linking agent blended with an isocyanate compound (CoronateHX: C / HX, manufactured by Japan Polyurethane Co., Ltd.) 18 parts by mass, 0.04 parts by mass of catalyst-based iron (III) acetoacetone (manufactured by Tokyo Chemical Industry Co., Ltd.), and ionic polysiloxane X-40-2450 (manufactured by Shin-Etsu Chemical Industry Co., Ltd.) was mixed with 0.5 parts by mass of 210 parts by mass of ethyl acetate in a dilute solvent system to prepare a urethane-based adhesive solution. Then, in the same manner as in Example 1, the heating conditions and the like and the thickness of the adhesive layer to be obtained were adjusted to prepare an adhesive sheet.

<Example 9> [Preparation of polysiloxane adhesive solution] As the polysiloxane adhesive, 100 parts by mass of "X-40-3229" (solid content of 60% by mass, manufactured by Shin-Etsu Chemical Industry Co., Ltd.) was used. 1.0.5 parts by mass of "CAT-PL-50T" (made by Shin-Etsu Chemical Industry Co., Ltd.), 0.5 parts by mass of ionic polysiloxane X-40-2450 (made by Shin-Etsu Chemical Co., Ltd.), and 100 parts by mass of solvent The toluene fraction was blended to prepare a polysiloxane-based adhesive solution. Then, in the same manner as in Example 1, and adjusting the heating conditions and the like and the thickness of the adhesive layer to be obtained, an adhesive sheet was prepared.

<Comparative Examples 1 to 4> An adhesive sheet was produced in the same manner as in Example 2 except that the ionic compounds described in Table 1 were used instead of the polysiloxane containing ionic groups used in Example 2.

<Comparative Example 5> An adhesive sheet was produced in the same manner as in Example 3, except that EMIFSI was used instead of the polysiloxane containing ionic groups used in Example 3.

Table 1 shows the above-mentioned blending contents of the adhesive sheets of Examples and Comparative Examples, and the results of various measurements and evaluations. The abbreviations in Table 1 are described below.

[Oxyalkylene-containing compound] KF353: Organic polysiloxane having an oxyalkylene chain (HLB 値: 10), manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name: KF-353 PD420: does not contain organic polysiloxane Oxygenated alkylene compound (HLB 値: 12.6), manufactured by Kao Corporation, trade name: LATEMUL PD-420

[Ionic compound (antistatic component)] X-40-2450: polysiloxane containing ionic group, manufactured by Shin-Etsu Chemical Co., active ingredient 55% X-40-2750: polysiloxane containing ionic group, Shin-Etsu Chemical Co., Ltd. System, active ingredient 100% LiTFSI: lithium bis (trifluoromethanesulfonyl) fluorenimide, alkali metal salt, manufactured by Tokyo Chemical Industry Co., Ltd., active ingredient 100% EMIFSI: 1-ethyl-3-methylimidazolium bis (Fluorosulfofluorenyl) fluorenimine, an ionic liquid, manufactured by Daiichi Kogyo Co., Ltd., with 100% active ingredient BMPTFSI: 1-butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) sulfonium Ionic liquid, manufactured by Aldrich, 100% active ingredient MTOATFSI: methyltrioctyl ammonium bis (trifluoromethanesulfonyl) sulfonium imine, manufactured by Wako Pure Chemical Industries, Ltd., 100% active ingredient

[Table 1]

From Table 1, it can be confirmed that the antistatic properties and the stability over time of the peeling electrostatic potential of all the examples were excellent. In addition, when the blending amount of the ionic group-containing polysiloxane was adjusted to a desired range and blended, it was confirmed that the stain resistance (low pollution) was also excellent.

On the other hand, from Table 1, it can be confirmed that all the comparative examples used antistatic agents such as ionic liquids instead of polysiloxanes containing ionic groups. Therefore, compared with the examples, the antistatic properties and the stability over time of the peeling electrostatic potential were poor. In particular, since polysiloxane containing ionic groups is not used, and it has been confirmed that the peeling electrostatic potential increases significantly with time, I speculate that the ionic compound contained in the adhesive layer penetrates into the surface of the polarizing plate over time.

Industrial Applicability The adhesive sheet disclosed here can be suitably used as a surface protection film for manufacturing components that can be used as a liquid crystal display panel, a plasma display panel (PDP), an organic electroluminescence (EL) display, and the like. In the case of an optical member, the optical member is protected during transportation and the like. It is especially useful as a surface protection film (optical surface protection film) for optical components such as polarizing plates (polarizing films), wavelength plates, retardation plates, optical compensation films, brightness enhancement films, light diffusion sheets, and reflection sheets for liquid crystal display panels. film).

1‧‧‧ Adhesive sheet (surface protection film)

1’‧‧‧ Adhesive sheet with separator (surface protection film)

10‧‧‧ acrylic board

11‧‧‧ Separator

12‧‧‧ Polysiloxane coating with ionic group

13‧‧‧Adhesive layer

14‧‧‧ substrate film

20‧‧‧ polarizing plate

30‧‧‧Sample fixing table

40‧‧‧ Potentiometer

FIG. 1 is a schematic cross-sectional view showing a structural example of an adhesive sheet (surface protection film) of the present invention. FIG. 2 is an explanatory diagram showing a method for measuring a peeling electrostatic potential.

Claims (7)

An adhesive composition comprising an adhesive polymer and a polysiloxane containing an ionic group represented by the following formula (1); [Chemical Formula 1] (R ₁ to R ₄ may be the same or different from each other, and contain any one of an alkyl group, an alkoxy group, an aryl group, an alicyclic group, a fluorine-substituted alkyl group, and an ionic group, and R ₁ 1 or more of ~ R ₄ contains an ionic group; n is an integer from 0 to 100). The adhesive composition according to claim 1, which contains an oxygen-containing alkylene compound. For example, the adhesive composition of claim 1 or 2 contains at least one selected from the group consisting of an acrylic adhesive, a urethane-based adhesive, and a polysiloxane-based adhesive. An adhesive sheet is characterized in that it has an adhesive layer formed of the adhesive composition according to any one of claims 1 to 3 on at least one side of a substrate film, and the aforementioned adhesive layer has The aforementioned ionic group-containing polysiloxane exists. The adhesive sheet according to claim 4, wherein a separator is attached to the opposite side of the surface of the adhesive layer that is in contact with the substrate film. For example, in the adhesive sheet of claim 5, wherein the surface of the separator in contact with the adhesive layer has the aforementioned ionic group-containing polysiloxane. An optical member is characterized by being attached with an adhesive sheet as claimed in claim 4 or an adhesive sheet obtained by peeling off the aforementioned separation member from the adhesive sheet as claimed in claim 5 or 6.