KR20180077042A - Adhesive composition, adhesive sheet and optical member - Google Patents

Abstract

The present invention provides an adhesive composition having less slippage (dislocation), lifting, or peeling on an optical member such as a polarizing plate or the like, having excellent curl adjustability, and suppressing peeling electrification voltage to a low level, an adhesive sheet formed by the adhesive composition, and an optical member on which the adhesive sheet is attached. The adhesive composition contains an adhesive polymer and a fluoric oligomer having an average molecular weight of 3500 or more and an ionic compound.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a pressure-sensitive adhesive composition,

The present invention relates to a pressure-sensitive adhesive composition, a pressure-sensitive adhesive sheet and an optical member. Particularly, the pressure-sensitive adhesive sheet obtained by the above pressure-sensitive adhesive composition is used for applications (for example, a liquid crystal display panel, a plasma display panel (PDP), an organic electroluminescence (EL) display, And particularly, a surface used for the purpose of protecting the surface of an optical member (for example, a polarizing plate, a wave plate, a retardation plate, an optical compensation film, a reflection sheet, a brightness enhancement film used for a liquid crystal display or the like) And is useful as a protective film.

The surface protective film (also referred to as a surface protective sheet) generally has a constitution in which a pressure-sensitive adhesive layer is provided on a base film (support) on a film. Such a protective film is bonded to an adherend (subject to be protected) via the above-mentioned pressure-sensitive adhesive layer, and is thereby used for the purpose of protecting the adherend from scratches and contamination during processing and transportation. For example, a panel of a liquid crystal display is formed by bonding an optical member such as a polarizing plate or a wave plate to a liquid crystal cell via a pressure-sensitive adhesive layer. In the manufacture of such a liquid crystal display panel, a polarizing plate bonded to a liquid crystal cell is firstly formed into a roll shape, then taken out from the roll, and cut to a desired size according to the shape of the liquid crystal cell. Here, in order to prevent the polarizing plate from rubbing with the conveying roll or the like in the intermediate process and scratching, a measure for bonding the surface protective film to one side or both sides (typically, one side) of the polarizing plate is taken. The surface protective film is peeled off at an unnecessary step.

Normally, since the surface protective film or the optical member is made of a plastic material, the electrical insulation is high, and static electricity is generated by friction or peeling. Therefore, static electricity is liable to be generated even when the surface protective film is peeled from an optical member such as a polarizing plate. When a voltage is applied to the liquid crystal in a state where the static electricity remains, the orientation of the liquid crystal molecules is lost, There is a possibility of occurrence or danger. In addition, the presence of static electricity may be a cause of sucking dust and deteriorating workability. For this reason, antistatic treatment is applied to the surface protective film. For example, by forming an antistatic layer or applying an antistatic coating to the surface layer (top coat layer and back layer) of the surface protective film, (See Patent Documents 1 and 2).

In order to impart antistatic properties to the pressure-sensitive adhesive layer itself constituting the surface protective film, an ionic compound such as an alkali metal salt or an ionic liquid serving as an antistatic agent is contained in the pressure-sensitive adhesive.

In the surface protective film, an unnecessary curl or an unintentional curl (curling phenomenon is referred to as "curl") in an adherend (polarizer, etc.) to which a surface protective film is adhered when adhered to an adherend A curling property is required to prevent a phenomenon such as a phenomenon in which the flat plate is entirely curled to one side, and a phenomenon in which the flat plate is waved as a whole). If unnecessary curl or unintended curl is generated, the handling property is deteriorated, and, for example, when an adherend such as a polarizing plate is attached to the liquid crystal cell, problems such as incorporation of bubbles may occur.

When curling occurs on a plate-like adherend, a force accompanying the curling acts on the pressure-sensitive adhesive layer of the surface protective film bonded to the adherend in the shearing direction, and by this force, the adhesive layer and the pressure- The shear force at the time of low-speed peeling is required to be improved.

In addition, when the adherend (object to be protected) is processed and transported, a light fastness (re-releasability) is required at a low speed peeling while having a proper adhesive force so as not to cause lifting or peeling of the surface protective film have.

Thus, in order to realize delamination, various methods are applied to the pressure-sensitive adhesive composition used for the surface protective film. For example, there have been reported examples in which a polymer used in a pressure-sensitive adhesive composition contains a component having a high glass transition temperature (Tg) or a reactive surfactant, and an example in which a pressure-sensitive adhesive composition is highly crosslinked (for example, Patent Document 4 Reference).

However, even in the case where the delamination can be realized by the above method, the additive such as an ionic compound or a surfactant is contained, whereby the additive bleeds out at the interface between the pressure-sensitive adhesive layer and the adherend, There is a possibility that slippage (deviation) may easily occur.

Japanese Patent Application Laid-Open No. 2004-223923 Japanese Patent Application Laid-Open No. 2008-255332 Japanese Patent Laid-Open No. 9-165460 Japanese Patent Application Laid-Open No. 2002-221906

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and as a result, the present invention has been made in view of the above circumstances and it is an object of the present invention to provide a polarizing plate and a polarizing plate which are excellent in slip (displacement), peeling and peeling, A pressure-sensitive adhesive sheet comprising the pressure-sensitive adhesive composition, and an optical member to which the pressure-sensitive adhesive sheet is adhered.

That is, the pressure-sensitive adhesive composition of the present invention is characterized by containing a pressure-sensitive adhesive polymer, a fluoric oligomer having a weight average molecular weight of 3500 or more, and an ionic compound.

The pressure-sensitive adhesive composition of the present invention preferably contains an oxyalkylene group-containing compound.

In the pressure-sensitive adhesive composition of the present invention, it is preferable that the pressure-sensitive adhesive polymer is at least one selected from the group consisting of a (meth) acrylic polymer, a urethane polymer and a silicone polymer.

It is preferable that the pressure-sensitive adhesive sheet of the present invention has a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition on at least one side of the base film, and the fluoric oligomer is present inside and / or on the surface of the pressure-sensitive adhesive layer.

In the pressure-sensitive adhesive sheet of the present invention, it is preferable that a separator is adhered to the surface of the pressure-sensitive adhesive layer opposite to the surface contacting the base film.

In the pressure-sensitive adhesive sheet of the present invention, it is preferable that the fluoric oligomer is present on the surface of the separator in contact with the pressure-sensitive adhesive layer.

In the optical member of the present invention, it is preferable that an adhesive sheet obtained by peeling the separator from the adhesive sheet or the adhesive sheet is attached.

The present invention relates to a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive composition comprising a specific fluorinated oligomer and an ionic compound, The occurrence of peeling can be suppressed, so that the curl adjustability is excellent and the peeling electrification voltage can be suppressed to a low level, which is useful.

Fig. 1 is a schematic cross-sectional view showing one configuration example of an adhesive sheet (surface protective film) according to the present invention.
2 is an explanatory view showing a method of measuring the peeling electrification voltage.

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

≪ Overall structure of adhesive sheet (surface protective film) >

The pressure-sensitive adhesive sheet disclosed herein is generally in the form of an adhesive tape, an adhesive label, an adhesive film or the like, and particularly relates to an optical component (for example, an optical component used as a component of a liquid crystal display panel such as a polarizing plate, ) Is suitable as a surface protective film for protecting the surface of an optical component during processing or transportation. The pressure-sensitive adhesive layer in the above-mentioned surface protective film is typically formed continuously, but the pressure-sensitive adhesive layer is not limited to this, and may be, for example, a pressure-sensitive adhesive layer formed in a regular or random pattern such as a dot pattern or a stripe pattern. The surface protective film disclosed herein may be in a roll form or in a leaf form.

<Base film>

The pressure-sensitive adhesive sheet (surface protective film) of the present invention is characterized by having a base film. In the techniques disclosed herein, the resin material constituting the base film can be used without any particular limitation, and for example, it is possible to use a resin material having excellent properties such as transparency, mechanical strength, heat stability, moisture barrier property, isotropy, flexibility, dimensional stability Is preferably used. Particularly, since the base film has flexibility, the pressure-sensitive adhesive composition can be applied by a roll coater or the like, and it can be wound in a roll form, which is useful.

Examples of the base film (substrate, support) include polyester polymers such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate; Cellulose-based polymers such as diacetylcellulose and triacetylcellulose; Polycarbonate-based polymers; Acrylic polymers such as polymethyl methacrylate; Or the like as a main resin component (a main component in a resin component, typically a component that occupies 50% by mass or more) can be preferably used as the base film. Other examples of the resin material include styrene polymers such as polystyrene and acrylonitrile-styrene copolymer; Olefin polymers such as polyethylene, polypropylene, polyolefins having a cyclic or norbornene structure, and ethylene-propylene copolymers; Vinyl chloride polymers; Amide polymers such as nylon 6, nylon 6,6, and aromatic polyamides; And the like as a resin material. As another example of the resin material, there may be mentioned imide polymers, sulfone polymers, polyether sulfone polymers, polyether ether ketone polymers, polyphenylene sulfide polymers, vinyl alcohol polymers, vinylidene chloride polymers, Based polymer, an aryl-based polymer, a polyoxymethylene-based polymer, and an epoxy-based polymer. Or a base film containing two or more kinds of blends of the above-mentioned polymers.

As the base film, a plastic film containing a transparent thermoplastic resin material can be preferably employed. Of the above plastic films, a polyester film is more preferable. Here, the polyester film refers to a polyester-based polymer material (polyester resin) having a main skeleton based on an ester bond such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate, Resin component. Such a polyester film has favorable properties as a substrate film of a surface protective film, such as excellent optical properties and dimensional stability, and has a property of being easily charged.

Various additives such as antioxidants, ultraviolet absorbers, plasticizers, colorants (pigments, dyes, etc.) may be added to the resin material constituting the base film, if necessary. For example, known or conventional surface treatments such as corona discharge treatment, plasma treatment, ultraviolet ray irradiation treatment, acid treatment, alkali treatment, and application of a primer may be performed. Such a surface treatment may be, for example, a treatment for enhancing the adhesion (adhesion property of the pressure-sensitive adhesive layer) between the base film and the pressure-sensitive adhesive layer.

The pressure-sensitive adhesive sheet (surface protective film) of the present invention may be a plastic film which is subjected to antistatic treatment as the base film. The use of the above base film is preferable because the charging of the pressure-sensitive adhesive sheet itself upon peeling can be suppressed. In addition, when the substrate film is a plastic film and the antistatic treatment is applied to the plastic film, it is possible to reduce the electrification of the pressure-sensitive adhesive sheet itself and to obtain an excellent antistatic property against the adherend. The method for imparting an antistatic function is not particularly limited and conventionally known methods can be used. For example, an antistatic resin or a conductive polymer containing an antistatic agent and a resin component, a conductive resin containing a conductive substance A method of depositing or plating a conductive material, a method of kneading an antistatic agent or the like, and the like.

The thickness of the base film is usually about 5 to 200 占 퐉, preferably about 10 to 100 占 퐉. When the thickness of the base film is within the above range, bonding workability to the adherend and peeling workability from the adherend are excellent.

The pressure-sensitive adhesive sheet disclosed herein can be carried out in a form including a further layer in addition to the base film and the pressure-sensitive adhesive layer. Examples of the other layer include an undercoating layer (anchor layer) for enhancing the transparency of the antistatic layer and the pressure-sensitive adhesive layer.

&Lt; Pressure sensitive adhesive composition &

The pressure-sensitive adhesive composition of the present invention can be used without any particular limitations as long as it contains a pressure-sensitive adhesive polymer, and a pressure-sensitive adhesive layer can be formed from the pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition may, for example, be an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a synthetic rubber pressure-sensitive adhesive, a natural rubber pressure-sensitive adhesive or a silicone pressure-sensitive adhesive. More preferably, At least one member selected from the group consisting of a silicone-based polymer, an acrylic pressure-sensitive adhesive containing a (meth) acrylic polymer, a urethane pressure-sensitive adhesive containing a urethane-based polymer, and a silicone- (Containing) the acrylic pressure-sensitive adhesive, more preferably, an acrylic pressure-sensitive adhesive using the (meth) acrylic polymer as the pressure-sensitive adhesive polymer.

When the pressure-sensitive adhesive layer uses an acrylic pressure-sensitive adhesive, the (meth) acrylic polymer as the pressure-sensitive adhesive polymer constituting the acrylic pressure-sensitive adhesive may be obtained by copolymerizing (meth) acrylic monomers having an alkyl group having 1 to 14 carbon atoms It can be used as a monomer. As the (meth) acrylic monomers, one type or two or more types can be used. By using the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, it is easy to control the peeling force (adhesive force) to an adherend (subject to be protected) to a low level, An adhesive sheet (surface protective film) is obtained. The (meth) acrylic polymer in the present invention refers to an acrylic polymer and / or a methacrylic polymer, and (meth) acrylate refers to acrylate and / or methacrylate.

Specific examples of the (meth) acrylic monomers having an alkyl group of 1 to 14 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, (Meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (Meth) acrylate, n-dodecyl (meth) acrylate, n-octyl (meth) acrylate, Tridecyl (meth) acrylate, and n-tetradecyl (meth) acrylate.

Among them, n-butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (Meth) acrylate, isodecyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (Meth) acrylic monomers having an alkyl group having 4 to 14 carbon atoms such as n-decyl (meth) acrylate, n-tridecyl (meth) acrylate and n-tetradecyl (meth) acrylate. In particular, by using a (meth) acrylic monomer having an alkyl group having 4 to 14 carbon atoms, it is easy to control the peeling force (adhesive force) on the adherend to be low, and the re-peeling property is excellent.

In particular, it is preferable that the (meth) acrylic polymer contains 50 mass% or more of (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms relative to 100 mass% of the total amount of the monomer components constituting the (meth) acrylic polymer, more preferably 80 By mass or more, more preferably 85 to 99.9% by mass, and most preferably 90 to 99% by mass. When the content is less than 50% by mass, the appropriate wettability of the pressure-sensitive adhesive composition and the cohesive force of the pressure-sensitive adhesive layer become poor, which is not preferable.

Further, in the pressure-sensitive adhesive composition of the present invention, it is preferable that the (meth) acryl-based polymer contains a hydroxyl group-containing (meth) acrylic monomer as a raw material monomer. The hydroxyl group-containing (meth) acrylic monomers may be used alone or in combination of two or more. By using the hydroxyl group-containing (meth) acrylic monomer, crosslinking and the like of the pressure-sensitive adhesive composition can be easily controlled, and the balance between improvement in wettability due to flow and reduction in peeling force (adhesive force) It becomes easier to do.

Examples of the hydroxyl group-containing (meth) acrylic monomers include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) (Meth) acrylate, 2-hydroxybutyl (meth) acrylate, hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl Hexyl) methyl acrylate, N-methylol (meth) acrylamide, and the like. In particular, the use of a (meth) acrylic monomer containing a hydroxyl group having 4 or more carbon atoms in the alkyl group makes it possible to facilitate delamination during high-speed peeling, which is preferable.

The (meth) acrylic polymer preferably contains 25 mass% or less, more preferably 20 mass% or less, of the hydroxyl group-containing (meth) acrylic monomer based on 100 mass% of the total amount of the monomer components constituting the (meth) , Preferably 0.1 to 15 mass%, and most preferably 1 to 10 mass%. Within this range, it is preferable to control the balance between the wettability of the pressure-sensitive adhesive composition and the cohesive force of the resulting pressure-sensitive adhesive layer.

Further, as other polymerizable monomer components, the glass transition temperature and the peelability of the (meth) acryl-based polymer are adjusted so that the Tg becomes 0 deg. C or lower (usually -100 deg. C or higher) And the like can be used within a range that does not impair the effect of the present invention.

Examples of other polymerizable monomers other than the (meth) acrylic monomers having an alkyl group having 1 to 14 carbon atoms and the hydroxyl group-containing (meth) acrylic monomers used in the (meth) acrylic polymer include carboxyl group-containing (meth) Monomers can be used. The use of the carboxyl group-containing (meth) acrylic monomers can suppress the increase of the adhesive strength with time in the pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet), and is excellent in re-peeling property, adhesive strength rise prevention property and workability. Further, it is preferable that the pressure-sensitive adhesive layer has excellent cohesive force and shear force.

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

The content of the carboxyl group-containing (meth) acrylic monomer is preferably 0 to 5% by mass, more preferably 0 to 3% by mass, and more preferably 0 to 3% by mass based on 100% by mass of the total amount of the monomer components constituting the (meth) By mass to 2% by mass, and most preferably 0% by mass to 1% by mass. Within this range, it is preferable to control the balance between the wettability of the pressure-sensitive adhesive composition and the cohesive force of the resulting pressure-sensitive adhesive layer.

When the hydroxyl group-containing (meth) acryl-based monomer and the carboxyl group-containing (meth) acryl-based monomer are used in combination, the content of the carboxyl group-containing (meth) acrylic monomer in the total amount of the monomer components constituting the (meth) Meth) acrylic monomer in an amount of 0.005 to 0.1% by mass. By adjusting to the above-mentioned range, a pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet) which is further excellent in releasability and prevention of rise of adhesion force is obtained, which is effective.

(Meth) acrylic monomer other than the (meth) acrylic monomer having a carboxyl group and the carboxyl group-containing (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, which is used in the (meth) acrylic polymer, The monomer is not particularly limited and may be used as far as it does not impair the properties of the present invention. For example, a cohesive force / heat resistance improving component such as a cyano group-containing monomer, a vinyl ester monomer, and an aromatic vinyl monomer, an amide group-containing monomer, an imide group-containing monomer, an amino group-containing monomer, an epoxy group- , A component having a functional group acting as an improvement point of a peeling force (adhesive force) of a vinyl ether monomer or the like or a point of crosslinking can be suitably used. Among them, it is preferable to use a cyano group-containing monomer, an amide group-containing monomer, an imide group-containing monomer, an amino group-containing monomer and a nitrogen-containing monomer such as N-acryloylmorpholine. By using the nitrogen-containing monomer, an appropriate peeling force (adhesive force) that does not cause lifting or peeling can be secured, and a pressure-sensitive adhesive sheet (surface protective film) excellent in shearing force can be obtained. 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 amide group-containing monomer include acrylamide, methacrylamide, diethylacrylamide, N-vinylpyrrolidone, N, N-dimethylacrylamide, N, N, N'-methylenebisacrylamide, N, N-dimethylaminopropylacrylamide, N, N-dimethylaminopropylmethacrylamide, diacetone acrylamide And the like.

Examples of the imide group-containing monomer include cyclohexylmaleimide, isopropylmaleimide, N-cyclohexylmaleimide and itaconimide.

Examples of the amino group-containing monomer include aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate.

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

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

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, isobutyl vinyl ether, and the like.

In the present invention, other polymerizable monomers other than the (meth) acrylic monomers having an alkyl group of 1 to 14 carbon atoms, the hydroxyl group-containing (meth) acrylic monomers and the carboxyl group-containing (meth) Is preferably 0 to 50% by mass, more preferably 0 to 20% by mass, based on 100% by mass of the total amount of the monomer components constituting the polymer. The other polymerizable monomers can be suitably adjusted in order to obtain desired properties.

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

The average addition mole number of oxyalkylene units in the alkylene oxide group-containing reactive monomer is preferably 1 to 40, more preferably 3 to 40, from the viewpoint of compatibility with the oxyalkylene group-containing compound, More preferably from 4 to 35, and particularly preferably from 5 to 30. When the average added mole number is 1 or more, there is a tendency that the effect of reducing the stain on the adherend (subject to be protected) is efficiently obtained. When the above-mentioned average addition mole number is more than 40, the interaction with the oxyalkylene group-containing compound is large and the viscosity of the pressure-sensitive adhesive composition tends to rise, which tends to make coating difficult. The terminal of the oxyalkylene chain may be a hydroxyl group, or may be substituted with another functional group or the like.

The alkylene oxide group-containing reactive monomer may be used singly or in admixture of two or more. The content of the alkylene oxide group-containing reactive monomer is preferably 0 to 20% by mass of the total amount of the monomer components of the (meth) acrylic polymer , More preferably from 0 to 10% by mass. When the content of the alkylene oxide group-containing reactive monomer is more than 20% by mass, the stain resistance to an adherend deteriorates, which is not preferable.

The oxyalkylene unit of the alkylene oxide group-containing reactive monomer includes those having an alkylene group having 1 to 6 carbon atoms, and examples thereof include oxymethylene group, oxyethylene group, oxypropylene group, oxybutylene group and the like. . The hydrocarbon group of the oxyalkylene chain may be straight chain or may be branched.

It is more preferable that the alkylene oxide group-containing reactive monomer is a reactive monomer having an ethylene oxide group. The use of the (meth) acrylic polymer containing a reactive monomer having an ethylene oxide group as the base polymer improves the compatibility between the base polymer and the fluorinated oligomer or the oxyalkylene group-containing compound and appropriately suppresses the bleeding to the adherend, A low-staining pressure-sensitive adhesive composition is obtained.

Examples of the alkylene oxide group-containing reactive monomer include alkylene oxide adducts of (meth) acrylic acid and reactive surfactants having reactive substituents such as acryloyl groups, methacryloyl groups and allyl groups in the molecule, and the like have.

Specific examples of the (meth) acrylate alkylene oxide adduct include polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, polyethylene glycol-polypropylene glycol (meth) acrylate, polyethylene glycol- (Meth) acrylate, methoxypolyethylene glycol (meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, butoxypolyethylene glycol (meth) acrylate, (Meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, stearoxypolyethylene glycol (meth) acrylate, phenoxypolyethylene glycol Acrylate, octoxypolyethylene glycol-polypropylene glycol ( Agent) acrylate.

Specific examples of the reactive surfactant include anionic type reactive surfactants having a (meth) acryloyl group or an allyl group, nonionic reactive surfactants, and cationic reactive surfactants.

The (meth) acrylic polymer preferably has a weight average molecular weight (Mw) of 100,000 to 5,000,000, more preferably 200,000 to 4,000,000, still more preferably 300,000 to 3,000,000, and most preferably 300,000 to 1,000,000. It is 95 million. When the weight-average molecular weight is less than 100,000, the cohesive force of the pressure-sensitive adhesive layer is decreased, and the pressure-sensitive adhesive tends to remain. On the other hand, when the weight average molecular weight exceeds 500,000, the fluidity of the polymer is lowered, the wettability to the adherend (for example, the polarizing plate) becomes insufficient, and the adhesion between the adherend and the pressure- Which is a cause of the swelling that occurs in the ink. The weight average molecular weight refers to a value obtained by measurement by GPC (gel permeation chromatography).

The glass transition temperature (Tg) of the (meth) acrylic polymer is preferably 0 ° C or lower, more preferably -10 ° C or lower (usually -100 ° C or higher). When the glass transition temperature is higher than 0 占 폚, the polymer is difficult to flow, for example, the wetting of the polarizing plate as an optical member becomes insufficient, and the cause of the expansion occurring between the polarizing plate and the pressure-sensitive adhesive layer of the pressure- . Especially when the glass transition temperature is lower than -61 캜, a pressure-sensitive adhesive layer having excellent wettability and light fastness to a polarizing plate tends to be obtained. The glass transition temperature of the (meth) acryl-based polymer can be adjusted within the above-mentioned range by suitably changing the monomer components and the composition ratio to be used.

The polymerization method of the (meth) acrylic polymer is not particularly limited, and the polymerization can be carried out by a known method such as solution polymerization, emulsion polymerization, bulk polymerization and suspension polymerization. In particular, from the viewpoint of workability, In view of properties such as low staining property against a protective body, solution polymerization is a more preferable form. The resulting polymer may be a random copolymer, a block copolymer, an alternating copolymer, a graft copolymer or the like.

When a urethane-based pressure-sensitive adhesive is used for the pressure-sensitive adhesive layer, any appropriate urethane-based pressure-sensitive adhesive can be employed. As such urethane pressure-sensitive adhesives, those containing a urethane-based polymer which is a pressure-sensitive adhesive polymer obtained by reacting a polyol with a polyisocyanate compound are preferable. Examples of polyols include polyether polyols, polyester polyols, polycarbonate polyols, polycaprolactone polyols, and the like. Examples of the polyisocyanate compound include diphenylmethane diisocyanate, tolylene diisocyanate, and hexamethylene diisocyanate.

When a silicone-based pressure-sensitive adhesive is used for the pressure-sensitive adhesive layer, any suitable silicone-based pressure-sensitive adhesive can be employed. As such a silicone-based pressure-sensitive adhesive, those obtained by blending or agglomerating a silicone-based polymer, which is a pressure-sensitive adhesive polymer, can be employed.

Examples of the silicone pressure-sensitive adhesive include an addition cure type silicone pressure-sensitive adhesive and a peroxide curing type silicone pressure-sensitive adhesive. Of these silicone pressure-sensitive adhesives, an addition cure type silicone pressure-sensitive adhesive is preferable in that no peroxide (such as benzoyl peroxide) is used and no decomposition products are generated.

As a curing reaction of the addition reaction curing type silicone pressure sensitive adhesive, for example, in the case of obtaining a polyalkyl silicone pressure sensitive adhesive, a method of generally curing a polyalkyl hydrogen siloxane composition with a platinum catalyst may be mentioned.

<Fluorine oligomer>

The pressure-sensitive adhesive composition of the present invention is characterized by containing a pressure-sensitive adhesive polymer, a fluoric oligomer having a weight average molecular weight of 3500 or more, and an ionic compound. When the obtained pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet) is bonded to an optical member such as a polarizing plate by incorporating a fluoric oligomer having a weight average molecular weight of 3500 or more in the pressure-sensitive adhesive composition, the light- And the fluorine oligomer functions as a tackifier resin and improves the adhesiveness to suppress the slippage (displacement), lifting and peeling of the surface protective film, that is, the light fastness (peelability) and It is possible to achieve both compatibility with the adhesive property, which is a preferable form. The pressure-sensitive adhesive sheet of the present invention has a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition according to any one of claims 1 to 3 on at least one side of the base film, , It is preferable that the fluoric oligomer is present. The &quot; inside &quot; of the pressure-sensitive adhesive layer means, for example, the case where the pressure-sensitive adhesive layer is formed by using the pressure-sensitive adhesive composition containing the fluoric oligomer. The &quot; surface &quot; of the pressure-sensitive adhesive layer means, for example, a case where the fluoric oligomer contained in the pressure-sensitive adhesive layer containing the fluoric oligomer is present (expressed) on the surface of the pressure- (Transferred) from the surface of the separator to the surface of the pressure-sensitive adhesive layer from the surface of the separator when the pressure-sensitive adhesive layer is adhered to the surface of the separator in which the fluoric oligomer is previously applied Point.

The fluoric oligomer has a weight average molecular weight (Mw) of 3500 or more, preferably 5000 or more, more preferably 10000 or more, and further preferably 20000 or more. When the weight average molecular weight of the fluorine oligomer is 3500 or more, the function as a tackifier resin is further exerted to improve the adhesiveness, and slippage (slippage), lifting and peeling of the surface protective film can be suppressed. When the weight average molecular weight is 20,000 or more, it is preferable that the viscosity of the pressure-sensitive adhesive (composition) can be suppressed at the time of blending and the appearance after application of the pressure-sensitive adhesive is excellent. The upper limit of the weight average molecular weight (Mw) of the fluorine oligomer is preferably 200,000 or less, more preferably 100,000 or less. When it is 200,000 or less, it is preferable that the fluoric oligomer tends to be segregated on the surface, and the light-releasing effect is more easily exhibited.

Specific examples of the fluorine oligomer include commercially available products such as Megaface F-251, F-253, F-281, F-410, F-430, F-444, F- -511, F-551, F-552, F-553, F-554, F-555, F-556, F-557, F-558, F- , F-563, F-565, F-568, F-569, F-570, F-571 and F-572 710FL, 710FM, 730FL, 730LM (manufactured by NEOS), and the like. These compounds may be used alone or in combination of two or more.

The content of the fluoric oligomer is preferably from 0.01 to 10 parts by mass per 100 parts by mass of the pressure-sensitive adhesive polymer (base polymer, for example, (meth) acrylic polymer, urethane polymer, More preferably 0.02 to 7.5 parts by mass, still 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, it is preferable that the adhesive sheet of the present invention is capable of suppressing slippage (displacement), peeling, peeling, etc. after bonding the adhesive sheet to an optical member or the like, and having excellent light fastness. In order to satisfy the stain resistance, the content of the fluorinated oligomer is preferably 0.01 to 5.5 parts by mass relative to 100 parts by mass of the adhesive polymer.

<Ionic Compound>

The pressure-sensitive adhesive composition preferably contains an ionic compound and at least one of an alkali metal salt, an ionic liquid and an ionic group-containing silicone is preferably used as the ionic compound. By containing at least one of these ionic compounds, excellent antistatic properties and peeling electrification properties can be imparted.

Since the alkali metal salt has high ion dissociation property, it is preferable from the viewpoint of exhibiting excellent antistatic ability even in a small amount. Examples of the alkali metal salt include a cation containing Li ⁺ , Na ⁺ , K ⁺ and a cation selected from 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 -, ^{_{F (HF) n -, (}} 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 ^- Is suitably used as the metal salt. Li (CF ₃ SO ₂ ) ₂ N, Li (C ₂ F ₅ SO ₂ ) ₂ N, Li (FSO ₂ ), and the like are more preferably used as LiBr, LiI, LiBF ₄ , LiPF ₆ , LiSCN, LiClO ₄ , LiCF ₃ SO ₃ , Li _{) 2 N, Li (CF 3} SO 2) 3 lithium salt, such as C, and more preferably from _{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 and Li (CF ₃ SO ₂ ) ₃ C are used. These alkali metal salts may be used alone or in combination of two or more kinds.

The ionic liquid preferably includes an organic cation component represented by the following formulas (A) to (E) and an anionic component. Among these ionic liquids having an ionic cation, those having a melting point of 100 占 폚 or lower can be used to obtain an excellent antistatic property.

R _a in the formula (A) represents a hydrocarbon group having 4 to 20 carbon atoms, a functional group in which a part of the hydrocarbon group is substituted with a hetero atom, R _b and R _c are the same or different, Or 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, there is no R _c .

R _e in the formula (B) represents a hydrocarbon group having 2 to 20 carbon atoms, a functional group in which a part of the hydrocarbon group is substituted with a hetero atom, R _e , R _f and R _g are the same or different, A hydrocarbon group having 1 to 16 carbon atoms, and a functional group in which a part of the hydrocarbon group is substituted with a hetero atom.

R _h in the formula (C) represents a hydrocarbon group having 2 to 20 carbon atoms, a functional group in which a part of the hydrocarbon group is substituted with a hetero atom, R _i , R _j and R _k are the same or different, A hydrocarbon group having 1 to 16 carbon atoms, and a functional group in which a part of the hydrocarbon group is substituted with a hetero atom.

R ₁ , R _m , R _n and R _o are the same or different and each represents a hydrocarbon group of 1 to 20 carbon atoms, and a part of the hydrocarbon group is heteroatom (s) It can also be an atom-substituted functional group. Provided that when Z is a sulfur atom, R _o is absent.

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

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

Specific examples include, for example, 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-hexylpyridinium cation, 1-butyl-3-methylpyridinium cation, Ethyl-1-methylpyrrolidinium cation, 1-ethyl-1-methylpyrrolidinium cation, 1-butyl-3-methylpyridinium cation, Methyl-1-pentylpyrrolidinium cation, 1-methyl-1-hexylpyrrolidinium cation, 1-methyl-1-butylpyrrolidinium cation, Ethyl-1-butylpyrrolidinium cation, 1-ethyl-1-pentylpyrrolidinium cation, 1-ethyl-1-propylpyrrolidinium cation, Ethyl-1-heptylpyrrolidinium cation, 1,1-dipropylpyrrolidinium cation, 1-propyl-1-butylpyrrolidinium cation, 1,1-dibutylpyrrolidinium cation, Pyrrolidinium-2-one cation, 1-pro Dimethylpiperidinium cation, a 1-methyl-1-ethylpiperidinium cation, a 1-methyl-1-propylpiperidinium cation, a 1-methylpiperidinium cation, Methyl-1-butylpiperidinium cation, 1-methyl-1-pentylpiperidinium cation, 1-methyl-1-hexylpiperidinium cation, Ethyl-1-butylpiperidinium cation, 1-ethyl-1-butylpiperidinium cation, 1-ethyl-1-butylpiperidinium cation, 1-propyl-1-butylpiperidinium cation, a 1,1-dibutylpiperidinium cation, a 2-methyl-1-pyrolein cation, Ethyl-2-phenylindole cation, a 1,2-dimethyl indole cation, a 1-ethylcarbazole cation and an N-ethyl-N-methylmorpholinium cation.

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

As specific examples, there may be mentioned, for example, 1,3-dimethylimidazolium cation, 1,3-diethylimidazolium cation, 1-ethyl-3-methylimidazolium cation, 3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, Dimethylimidazolium cation, 1-ethyl-2,3-dimethylimidazolium cation, 1-butyl-2,3-dimethyl Imidazolium cation, 1-hexyl-2,3-dimethylimidazolium cation, 1- (2-methoxyethyl) -3-methylimidazolium cation, 1,3-dimethyl- - tetrahydropyrimidinium cation, 1,2,3-trimethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,2,3,4-tetramethyl-1,4,5,6- Tetrahydropyrimidinium cation, 1,2,3,5-tetramethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,3-dimethyl-1,4 Dihydropyrimidinium cation, a 1,3-dimethyl-1,6-dihydropyrimidinium cation, a 1,2,3-trimethyl-1,4-dihydropyrimidinium cation, a 1,2,3- 1,6-dihydropyrimidinium cation, 1,2,3,4-tetramethyl-1,4-dihydropyrimidinium cation, 1,2,3,4-tetramethyl-1,6- Dihydropyrimidinium cation and the like.

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

Specific examples include, for example, 1-methylpyrazolium cation, 3-methylpyrazolium cation, 1-ethyl-2-methylpyrazolium cation, 1-ethyl-2,3,5-trimethylpyrazolium cation, 2,3,5-trimethylpyrazolium cation, 1-butyl-2,3,5-trimethylpyrazolium cation, 1-ethyl-2,3,5-trimethylpyrazolium cation, -Trimethylpyrazolium cation, 1-butyl-2,3,5-trimethylpyrazolium cation, and the like.

Examples of the cation represented by the formula (D) include tetraalkylammonium cations, trialkylsulfonium cations and tetraalkylphosphonium cations, and those in which a part of the alkyl group is substituted with an alkenyl group, an alkoxyl group, .

As specific examples, there can be mentioned, for example, a tetramethylammonium cation, a tetraethylammonium cation, a tetrabutylammonium cation, a tetrapentylammonium cation, a tetrahexylammonium cation, a tetraheptylammonium cation, a triethylmethylammonium cation, a tributylethylammonium cation, (2-methoxyethyl) ammonium cation, a glycidyltrimethylammonium cation, a trimethylsulfonium cation, a triethylsulfonium cation, a tributylsulfonium cation, an ammonium cation, Tetraethylphosphonium cation, tetrabutylphosphonium cation, tetrahexylphosphonium cation, tetrabutylphosphonium cation, tetrabutylphosphonium cation, tetrabutylphosphonium cation, tetrabutylphosphonium cation, tetrabutylphosphonium cation, tetrabutylphosphonium cation, Tetraoctylphosphonium cation, triethylmethylphosphonium cation, tributylethylphosphonium cation, tetrabutylphosphonium cation, Decyl methyl phosphonium cation, a diallyl dimethyl ammonium cation, tributyl-and the like (2-methoxyethyl) phosphonium cation. Among them, triethylmethylammonium cation, tributylethylammonium cation, trimethyldecylammonium cation, diethylmethylsulfonium cation, dibutylethylsulfonium cation, dimethyldesylsulfonium cation, triethylmethylphosphonium cation, tributylethylphosphine Tetramethylammonium cation, tetramethylammonium cation, tetramethylammonium cation, tetramethylammonium cation, tetramethylammonium cation, tetramethylammonium cation, tetramethylammonium cation, tetramethylammonium cation, N-dimethyl-N-ethyl-N-butylammonium cation, N, N-dimethyl-N-ethyl-N-methylammonium cation, N-dimethyl-N-ethyl-N-heptylammonium cation, N, N-dimethyl-N-ethyl-N-pentylammonium cation, Dimethyl-N-ethyl-N-nonyl ammonium cation, N, N-dimethyl- N-dimethyl-N-propyl-N-propyl-N-butylammonium cation, N, N-dimethyl- N-dimethyl-N-butyl-N-heptylammonium cation, N, N-dimethyl-N-butyl-N-hexylammonium cation, , N, N-dimethyl-N-pentyl-N-hexylammonium cation, N, N-dimethyl- Propyl ammonium cation, N, N-diethyl-N-methyl-N-pentylammonium cation, N, N-diethyl- N, N-dipropyl-N-methylammonium cation, N, N-dipropyl-N-methylammonium cation, triethylammonium cation, N-dipropyl-N-butyl-N-hexylammonium cation, N, N-dipropyl-N, N- N, N-dibutyl-N-methyl-N-hexylammonium cation, trioctylmethylammonium cation, N-methyl-N- Ethyl-N-propyl-N-pentylammonium cations are preferably used.

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

On the other hand, the anion component is not particularly limited as long as it satisfies that it becomes an ionic liquid, and examples thereof include Cl ^- , Br ^- , I ^- , AlCl ₄ ^- , Al ₂ Cl ₇ ^- , BF ₄ ^- , PF ₆ ^- , SCN _{^{-, 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 -, CH 3 OSO 3 -, C ₂ H ₅ OSO ₃ ^- , C ₄ H ₉ 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 -, (FSO 2) 2 N -, B (CN) 4 -, C (CN) 3 -, N (CN) ₂ ^-, p- toluenesulfonate anion, a 2- (2-methoxy-ethyl) and the like ethyl sulfate anion.

These ionic liquids may be used alone or in combination of two or more.

The ionic group-containing silicon is preferably represented by the following formula (1).

R ₁ to R ₄ in the formula (1) may be the same or different and each represent an alkyl group, an alkoxy group, an aryl group, an alicyclic group, a fluorine-substituted alkyl group, or an ionic group having 1 to 10 carbon atoms, And at least one ionic group of R ₁ to R ₄ . n is an integer from 0 to 100;

As the ionic group contained in at least one of R ₁ to R ₄ , an ionic group having an ammonium cationic group or a phosphonium cationic group is preferable. Among them, it is preferable that at least one of R ₁ to R ₄ includes a cation structure represented by the following formula (a) or (b) and an anion component, or a cation structure represented by (c) or It is preferably a binary ion structure.

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

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

The anion component is not particularly limited and includes, for example, 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 ^- are used.

R ₁₁ and R ₁₂ in the formula (c) may be the same or different and each represent an alkyl group, an aryl group or a fluorine-substituted alkyl group having 1 to 10 carbon atoms, R ₁₁ and R ₁₂ may form a ring, Represents an alkylene group. m is an integer of 1 to 10, and p is an integer of 1 to 6.

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

Such an ionic group-containing silicone contains a silicon chain. Therefore, even when the pressure-sensitive adhesive layer is adhered to the surface of an adherend (for example, a polarizing plate) and stored under a high temperature environment by the low surface free energy of the silicon chain , The ionic group-containing silicon tends to stay on the surface of the pressure-sensitive adhesive layer without penetrating the ionic group-containing silicon (from the surface of the adherend to the inside of the adherend), so that the stripping electrification property is stable even with a long period of time, And can be suitably used as an antistatic agent.

Specific examples of the ionic group-containing silicon include trade names X-40-2450 and X-40-2750 (commercially available from Shin-Etsu Chemical Co., Ltd.), which are commercially available products. These compounds may be used alone or in combination of two or more.

The content of the ionic compound is preferably 0.01 to 10 parts by mass per 100 parts by weight of the pressure-sensitive adhesive polymer (base polymer, for example, (meth) acrylic polymer, urethane polymer, More preferably 0.02 to 7.5 parts by mass, still more preferably 0.03 to 5.5 parts by mass, and most preferably 0.04 to 4.8 parts by mass. Within this range, it is preferable that the pressure-sensitive adhesive sheet of the present invention has both antistatic properties and inhibition of slippage (misalignment).

&Lt; Oxyalkylene group-containing compound >

The pressure-sensitive adhesive composition of the present invention preferably contains an oxyalkylene group-containing compound, more preferably an organopolysiloxane having an oxyalkylene chain, more preferably an organopolysiloxane having an oxyalkylene backbone Is more preferable. By using the organopolysiloxane, it is presumed that the surface free energy of the surface of the pressure-sensitive adhesive is lowered and realization of light-exfoliation is realized.

As the organopolysiloxane, an organopolysiloxane having a known polyoxyalkylene backbone can be suitably used, but is preferably represented by the following formula (2).

In the formula (2), R ₁ and / or R ₂ may have an oxyalkylene chain having 1 to 6 carbon atoms, and the alkylene group in the oxyalkylene chain may be linear or branched, and the terminal of the oxyalkylene chain An alkoxy group, or a hydroxyl group. Either R ₁ or R ₂ may be a hydroxyl group, or may be an alkyl group, an alkoxy group, or a functional group in which a part of the alkyl group or alkoxy group is substituted with a hetero atom. n is an integer from 1 to 300;

The above-mentioned organopolysiloxane is one having a main chain containing a siloxane-containing moiety (siloxane moiety) and an oxyalkylene chain bonded to the end of the main chain. By using the organosiloxane having an oxyalkylene chain, balance of compatibility with the (meth) acrylic polymer, the fluoric oligomer and the ionic compound is balanced, and it is presumed that the exfoliation is realized.

As the organopolysiloxane in the present invention, for example, the following constitution can be used. Specifically, R ₁ and / or R ₂ in the formula have an oxyalkylene chain containing a hydrocarbon group having 1 to 6 carbon atoms, and examples of the oxyalkylene chain include oxymethylene group, oxyethylene group, oxypropylene group, oxybutylene group Among them, an oxyethylene group and an oxypropylene group are preferable. When both of R ₁ and R ₂ have an oxyalkylene chain, they may be the same or different.

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

The terminal of the oxyalkylene chain may be an alkoxy group or a hydroxyl group, and more preferably an alkoxy group. In the case of bonding the separator to the surface of the pressure-sensitive adhesive layer for the purpose of protecting the pressure-sensitive adhesive surface, in the organopolysiloxane having a terminal hydroxyl group, interaction with the separator occurs, and when the separator is peeled from the surface of the pressure- ) May be increased.

Also, n is an integer of 1 to 300, preferably 10 to 200, and more preferably 20 to 150. When n is within the above range, a balance of compatibility with the base polymer is obtained and a preferable form is obtained. The molecule may have a reactive substituent such as a (meth) acryloyl group, an allyl group, or a hydroxyl group. These organopolysiloxanes may be used alone or in combination of two or more.

Specific examples of the organopolysiloxane having an oxyalkylene chain in the main chain include commercially available products such as X-22-4952, X-22-4272, X-22-6266, KF-6004 and KF- , BY16-201, SF8427 (manufactured by Dow Corning Toray Co., Ltd.), IM22 (manufactured by Asahi Chemical Industry Co., Ltd.), and the like. These compounds may be used alone or in combination of two or more.

In addition to the above-mentioned organosiloxane having an oxyalkylene chain (bonding) in the main chain, an organosiloxane having an oxyalkylene chain in its side chain (bonding) may be used, and an organosiloxane having an oxyalkylene chain in the side chain The use of organosiloxanes is a more preferred form. As the organopolysiloxane, an organopolysiloxane having a known polyoxyalkylene side chain can be suitably used, but is preferably represented by the following formula (3).

Further, the formula (3) of, R ₁ is a monovalent organic group, R _2, R ₃ and R ₄ is an alkylene group, R ₅ is hydrogen or an organic group, m and n is an integer from 0 to 1000. However, m and n are not 0 at the same time. a and b are an integer of 0 to 100; However, a and b do not become 0 at the same time.)

As the organopolysiloxane in the present invention, for example, the following constitution can be used. Specifically, R ₁ in the formula is an alkyl group such as methyl group, ethyl group or propyl group, an aryl group such as phenyl group or tolyl group or a monovalent organic group exemplified as aralkyl group such as benzyl group or phenethyl group, And the like. R ₂ , R ₃ and R ₄ may be an alkylene group having 1 to 8 carbon atoms such as a methylene group, an ethylene group and a propylene group. Here, R ₃ and R ₄ may be different alkylene groups, and R ₂ may be the same as or different from R ₃ or R ₄ . R ₅ may be a monovalent organic group such as an alkyl group such as methyl group, ethyl group or propyl group or an acyl group such as acetyl group or propionyl group and 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) acryloyl group, an allyl group, or a hydroxyl group. Among these organosiloxanes having a polyoxyalkylene side chain, organosiloxane having a hydroxyl group-terminated polyoxyalkylene side chain is preferable because it is presumed that the compatibility of the organosiloxane is easy to obtain.

Specific examples of the organosiloxane having an oxyalkylene chain in the side chain include trade names KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF- KF-6012, KF-6022, X-22-4515, KF-6011, KF-6012, KF-6015, KF- FZ-2124, FZ-2162, FZ-2162, FZ-2124, FZ-2124, FZ- FZ-7001, SH8400, SH8700, SF8410, SF8422 (manufactured by Toray Dow Corning), TSF-4440, TSF-4441, TSF-4445, TSF-4450, TSF-4446, TSF- (BYK-333), BYK-307, BYK-377, BYK-UV3500 and BYK-UV3570 (manufactured by Big Chem Japan). These compounds may be used singly or in combination of two or more kinds.

As the organosiloxane used in the present invention, the Hydrophile-Lipophile Balance (HLB) value is preferably 1 to 16, more preferably 3 to 14. If the HLB value is out of the above-mentioned range, the stain resistance to the adherend becomes poor, which is not preferable.

The pressure-sensitive adhesive composition may contain an oxyalkylene group-containing compound not containing an organopolysiloxane. By incorporating the compound into the pressure-sensitive adhesive, a pressure-sensitive adhesive excellent in wettability to the adherend can be obtained.

Specific examples of the organopolysiloxane-free oxyalkylene group-containing compound include, for example, polyoxyalkylene alkylamine, polyoxyalkylene diamine, polyoxyalkylene fatty acid ester, polyoxyalkylene sorbitan fatty acid ester, poly Nonionic surfactants such as oxyalkylene alkylphenyl ethers, polyoxyalkylene alkyl ethers, polyoxyalkylene alkylallyl ethers, and polyoxyalkylene alkylphenyl allyl ethers; Anionic surfactants such as polyoxyalkylene alkyl ether sulfuric acid ester salts, polyoxyalkylene alkyl ether phosphoric acid ester salts, polyoxyalkylene alkyl phenyl ether sulfuric acid ester salts and polyoxyalkylene alkyl phenyl ether phosphoric acid ester salts; Other examples include cationic surfactants having a polyoxyalkylene chain (polyalkylene oxide chain), amphoteric surfactants, polyether compounds having polyoxyalkylene chains (including derivatives thereof), polyoxyalkylene chains (And derivatives thereof) and the like. Further, the polyoxyalkylene chain-containing monomer may be blended as a polyoxyalkylene chain-containing compound. These polyoxyalkylene chain-containing compounds may be used alone or in combination of two or more.

Specific examples of the polyether compound having a polyoxyalkylene chain (polyether component) include a block copolymer of polypropylene glycol (PPG) -polyethylene glycol (PEG), a block copolymer of PPG-PEG-PPG, a block copolymer of PEG-PPG -PEG block copolymers and the like. Examples of the derivative of the polyether compound having the polyoxyalkylene chain include compounds having terminally etherified oxypropylene group-containing compounds (PPG monoalkyl ether, PEG-PPG monoalkyl ether, etc.), oxypropylene group-containing compounds (Terminal acetylated PPG and the like), and the like.

Specific examples of the acrylic compound having a polyoxyalkylene chain include a (meth) acrylate polymer having an oxyalkylene group. As the oxyalkylene group, the number of moles of the oxyalkylene unit added is preferably 1 to 50, more preferably 2 to 30, and still more preferably 2 to 20. The terminal of the oxyalkylene chain may be substituted with an alkyl group, a phenyl group, or the like, while being a hydroxyl group.

The (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 (meth) acrylic acid alkylene oxide include ethylene Examples of the glycol group-containing (meth) acrylate include a methoxy-polyethylene glycol (meth) acrylate type such as methoxy-diethylene glycol (meth) acrylate and methoxy-triethylene glycol (meth) (Meth) acrylate type such as ethoxy-diethylene glycol (meth) acrylate and ethoxy-triethylene glycol (meth) acrylate, butoxy-diethylene glycol Butoxy-polyethylene glycol (meth) acrylate type such as methoxy-triethylene glycol (meth) acrylate, phenoxy-diethylene glycol (meth) Polyethylene glycol (meth) acrylate type such as triethylene glycol (meth) acrylate, 2-ethylhexylpolyethylene glycol (meth) acrylate, nonylphenol-polyethylene glycol And methoxy-polypropylene glycol (meth) acrylate type such as dipropylene glycol (meth) acrylate.

As the monomer unit (component), other monomer units (components) other than the (meth) acrylic acid alkylene oxide may be used. Specific examples of the other monomer components include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, s- (Meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (Meth) acrylate, n-decyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl ) Acrylate and / or methacrylate having an alkyl group having 1 to 14 carbon atoms.

(Meth) acrylate, a phosphoric acid group-containing (meth) acrylate, a cyano group-containing (meth) acrylate, a vinyl ester, an aromatic (meth) acrylate (Meth) acrylate, an epoxy group-containing (meth) acrylate, an amino group-containing (meth) acrylate, an N- Acryloylmorpholine, vinyl ethers, and the like may be suitably used.

As a more preferred form, the polyoxyalkylene chain-containing compound containing no organopolysiloxane is a compound having at least part of (poly) ethylene oxide chain. By blending the (poly) ethylene oxide chain-containing compound, the compatibility of the base polymer with the fluorinated oligomer or ionic compound is improved, bleeding to the adherend is suitably suppressed, and a pressure-sensitive adhesive composition of low staining property is obtained. In particular, when a block copolymer of PPG-PEG-PPG is used, a pressure-sensitive adhesive excellent in low staining property can be obtained. As the polyethylene oxide chain-containing compound, it is preferable that the weight of the (poly) ethylene oxide chain occupying in the entire polyoxyalkylene chain-containing compound not containing the organopolysiloxane is 5 to 90% by mass, 5 to 85% by mass, more preferably 5 to 80% by mass, still more preferably 5 to 75% by mass.

As the molecular weight of the organopolysiloxane-free polyoxyalkylene chain-containing compound, the number-average molecular weight (Mn) is preferably 50,000 or less, more preferably 200 to 30,000, further preferably 200 to 10000, 200 to 5000 are suitably used. When Mn is more than 50000, compatibility with the acrylic polymer is lowered, and the pressure-sensitive adhesive layer tends to whiten. If Mn is less than 200, contamination with the polyoxyalkylene compound may easily occur. Here, Mn means a value in terms of polystyrene obtained by GPC (gel permeation chromatography).

Specific examples of commercially available products of the polyoxyalkylene chain-containing compound containing no organopolysiloxane include adekafluronic 17R-4, adekafluoronic 25R-2 (all above, adeka AQUALON HS-10, KH-10, NOIGEN EA-87, EA-137 (manufactured by ADEKA), LATEMELL PD-420, LATEMELL PD- , EA-157, EA-167, and EA-177 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.).

The content of the oxyalkylene group-containing compound is preferably 0.01 to 5.0 parts by mass relative to 100 parts by mass of a pressure-sensitive adhesive polymer (base polymer, for example, (meth) acrylic polymer, urethane polymer, More preferably 0.02 to 2 parts by mass, still more preferably 0.03 to 1.6 parts by mass, and most preferably 0.1 to 0.8 parts by mass. Within the above range, it is preferable that the slip (deviation) and the light leathability (re-releasability) of the pressure-sensitive adhesive sheet of the present invention are easily compatible with each other.

<Cross-linking agent>

In the pressure-sensitive adhesive sheet (surface protective film) of the present invention, it is preferable that the pressure-sensitive adhesive composition contains a crosslinking agent. Further, in the present invention, the pressure-sensitive adhesive composition may be used to form a pressure-sensitive adhesive layer. For example, in the case of the acrylic pressure-sensitive adhesive containing the (meth) acryl-based polymer, the pressure-sensitive adhesive composition may be prepared by appropriately adjusting the crosslinking agent and the constituent units, constituent ratio, Sensitive adhesive sheet (pressure-sensitive adhesive layer) superior in heat resistance can be obtained.

As the crosslinking agent to be used in the present invention, an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative and a metal chelate compound may be used. In particular, the use of an isocyanate compound is a preferable form. 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, butylenediisocyanate, hexamethylene diisocyanate (HDI) and dimer acid diisocyanate, cyclopentylene diisocyanate, cyclohexylene diisocyanate, isophorone diisocyanate (IPDI) and 1,3-bis (isocyanatomethyl) cyclohexane; alicyclic isocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate (XDI) , An aromatic isocyanate compound such as an isocyanate compound represented by the following general formula (1), an isocyanate compound represented by the following general formula (1), an isocyanate compound such as an isocyanate compound, an isocyanate compound, a urea bond, a urea bond, a carbodiimide bond, And one polyisocyanate modified product. For example, as commercial products, trade names: Takenate 300S, Takenate 500, Takenate 600, Takenate D165N, Takenate D178N (manufactured by Takeda Chemical Industries, Ltd.), Sumidur T80, Sumidur L, (Available from Sumitomo Bayer Urethane Co., Ltd.), Millionate MR, Millionate MT, Coronate L, Coronate HL, Coronate HX (manufactured by Nippon Polyurethane Industry Co., Ltd.). These isocyanate compounds may be used alone, or two or more isocyanate compounds may be used in combination, or a bifunctional isocyanate compound and a trifunctional or higher isocyanate compound may be used in combination. When a crosslinking agent is used in combination, it is possible to obtain both a cohesive property and an anti-repulsion property (adhesiveness to a curved surface), and a pressure-sensitive adhesive sheet excellent in adhesion reliability can be obtained.

When a bifunctional isocyanate compound and a trifunctional or higher isocyanate compound are used in combination as the isocyanate compound, the [bifunctional isocyanate compound] / [trifunctional or higher isocyanate compound] is preferably used as the compounding ratio (mass ratio) (Mass ratio) is preferably from 0.1 / 99.9 to 50/50, more preferably from 0.1 / 99.9 to 20/80, even more preferably from 0.1 / 99.9 to 10/90, from 0.1 / 99.9 to 5/95 And most preferably 0.1 / 99.9 to 1/99. By adjusting the content within the above range, a pressure-sensitive adhesive layer excellent in tackiness and resistance to repulsion becomes a preferable form.

Examples of the epoxy compound include N, N, N ', N'-tetraglycidyl-m-xylenediamine (trade name TETRAD-X manufactured by Mitsubishi Gas Chemical Company) Diglycidylaminomethyl) cyclohexane (trade name: TETRAD-C, manufactured by Mitsubishi Gas Chemical Company).

Examples of the melamine resin include hexamethylol melamine and the like. Examples of the aziridine derivative include HDU, TAZM and TAZO (trade names, available from Sogo Kogyo Co., Ltd.) as commercial products.

Examples of the metal chelate compound include aluminum, iron, tin, titanium, nickel and the like as metal components, and acetylene, methyl acetoacetate, and ethyl lactate as chelate components.

The content of the crosslinking agent used in the present invention is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, and most preferably 0.5 to 10 parts by mass, based on 100 parts by mass of the (meth) acrylic polymer And most preferably 1 to 6 parts by mass. When the content is less than 0.01 part by mass, crosslinking by the crosslinking agent becomes insufficient, and the cohesive force of the obtained pressure-sensitive adhesive layer becomes small, so that sufficient heat resistance tends not to be obtained, and tends to cause adhesive residue. On the other hand, when the content is more than 20 parts by mass, the cohesive force of the polymer is large, the fluidity is decreased, the wettability to the adherend (for example, the polarizing plate) becomes insufficient and the adhesion between the adherend and the pressure- There is a tendency to cause a swelling that occurs. These crosslinking agents may be used alone or in combination of two or more.

The pressure-sensitive adhesive composition may further contain a crosslinking catalyst for further promoting any of the crosslinking reactions described above. Examples of such a crosslinking catalyst include tin-based catalysts such as dibutyltin dilaurate and dioctyltin dilaurate, tris (acetylacetonate) iron (iron (III) acetylacetonato), tris (Heptane-2,5-dianato) iron, tris (5-methylhexane-2,4-dianato) iron, tris Iron, tris (6-methylheptane-2,4-dianato) iron, tris (2,6-dimethylheptane- Iron, tris (nonane-4,6-dianato) iron, tris (2,2,6,6-tetramethylheptane-3,5-dianato) iron, tris (tridecane- Iron, tris (ethyl acetoacetate) iron, tris (acetoacetic acid-n-propyl acetoacetate) iron, tris (1-phenylbutane-1,3-dianato) iron, tris (hexafluoroacetylacetonate) ) Iron, tris (isopropyl acetoacetate), tris (acetoacetic acid-n-butyl) iron, Tris (acetoacetic acid-sec-butyl) iron, tris (acetoacetic acid-tert-butyl) iron, tris (propionylacetic acid methyl) Iron, tris (propionylacetic acid isopropyl) iron, tris (propionylacetate-n-butyl) iron, tris (propionylacetic acid-sec-butyl) Based catalysts such as benzoyl acetylacetonate, iron tris (dimethyl malonate), tris (diethyl malonate), trimethoxy iron, triethoxy iron, triisopropoxy iron and ferric chloride can be used . These crosslinking catalysts may be used alone or in combination of two or more.

The content of the crosslinking catalyst is not particularly limited, but is preferably about 0.0001 to 1 part by mass, more preferably 0.001 to 0.5 part by mass, relative to 100 parts by mass of the (meth) acrylic polymer. Within the above range, the speed of the crosslinking reaction is high when the pressure-sensitive adhesive layer is formed, and the use time of the pressure-sensitive adhesive composition becomes long, which is a preferable form.

In addition, the pressure-sensitive adhesive composition may contain a compound which generates keto-enol tautomerism. For example, in a pressure-sensitive adhesive composition which can be used in combination with a pressure-sensitive adhesive composition or a crosslinking agent containing a crosslinking agent, a form containing the compound capable of generating keto-enol tautomerism can be preferably employed. Thereby, it is possible to realize an effect of suppressing excessive viscosity increase or gelation of the pressure-sensitive adhesive composition after the crosslinking agent blend and prolonging the time available for the pressure-sensitive adhesive composition. When at least an isocyanate compound is used as the cross-linking agent, it is particularly meaningful to include a compound which generates keto-enol tautomerism. This technique can be preferably applied, for example, when the pressure-sensitive adhesive composition is in the form of an organic solvent solution or solvent.

As the compound capable of generating keto enol tautomerism, various? -Dicarbonyl compounds can be used. Specific examples include acetylacetone, 2,4-hexanedione, 3,5-heptanedione, 2-methylhexane-3,5-dione, 6-methylheptane- ? -Diketones such as 5-dione; Acetoacetic acid esters such as methyl acetoacetate, ethyl acetoacetate, isopropyl acetoacetate and tert-butyl acetoacetate; Propionyl acetic acid esters such as ethyl propionyl acetate, ethyl propionylacetate, isopropyl propionylacetate, and tert-butyl propionylacetate; Isobutyryl acetic acid esters such as ethyl isobutyryl acetate, ethyl isobutyryl acetate, isopropyl isobutyryl acetate and tert-butyl isobutyryl acetate; Malonic acid esters such as methyl malonic acid and ethyl malonic acid; And the like. Among them, acetylacetone and acetoacetic acid esters can be mentioned as suitable compounds. These compounds that generate keto-enol tautomerism may be used alone or in combination of two or more.

The content of the compound capable of generating keto enol tautomerism may be, for example, from 0.1 to 20 parts by mass, and usually from 0.5 to 15 parts by mass (for example, from 1 to 20 parts by mass) relative to 100 parts by mass of the (meth) 10 parts by mass). When the amount of the compound is too small, a sufficient use effect may not be exerted in some cases. On the other hand, if the compound is used in an excessively large amount, the adhesive may remain on the pressure-sensitive adhesive layer to lower the cohesive force.

The pressure-sensitive adhesive composition may contain other known additives, and examples thereof include powders such as a lubricant, a colorant and a pigment, a plasticizer, a tackifier, a low molecular weight polymer, a surface lubricant, a leveling agent, A stabilizer, a light stabilizer, an ultraviolet absorber, a polymerization inhibitor, a silane coupling agent, an inorganic or organic filler, a metal powder, a particulate or a foil, and the like.

&Lt; Pressure-sensitive adhesive layer and pressure-sensitive adhesive sheet (surface protective film) >

The pressure-sensitive adhesive sheet of the present invention is formed by forming the pressure-sensitive adhesive layer on at least one side of a base film. At this time, the pressure-sensitive adhesive composition is usually crosslinked after the application of the pressure-sensitive adhesive composition. It may be transferred to a base film or the like.

The method of forming the pressure-sensitive adhesive layer on the base film is not particularly limited. For example, the pressure-sensitive adhesive composition (solution) is coated on the base film and the pressure-sensitive adhesive layer is formed on the base film by drying and removing the polymerization solvent. do. After that, curing may be performed for the purpose of adjusting the component migration of the pressure-sensitive adhesive layer and adjusting the crosslinking reaction. When the pressure-sensitive adhesive composition is applied onto a base film to produce a pressure-sensitive adhesive sheet, at least one solvent other than the polymerization solvent may be newly added to the pressure-sensitive adhesive composition so that the pressure-sensitive adhesive composition can be uniformly applied on the base film.

As a method of forming a pressure-sensitive adhesive layer in the production of the pressure-sensitive adhesive sheet of the present invention, a known method used for production of pressure-sensitive adhesive tapes is used. Specific examples include extrusion coating methods such as roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating, die coater and the like.

The pressure-sensitive adhesive sheet of the present invention is usually manufactured so that the pressure-sensitive adhesive layer has a thickness of 3 to 100 탆, preferably 5 to 50 탆. When the thickness of the pressure-sensitive adhesive layer is within the above-mentioned range, it is preferable that a proper balance of re-peeling property and adhesiveness can be easily obtained.

The total thickness of the adhesive sheet of the present invention is preferably 8 to 300 占 퐉, more preferably 10 to 200 占 퐉, and most preferably 20 to 100 占 퐉. Within the above range, the adhesive property (re-releasability, adhesiveness, etc.), workability, and appearance are excellent, which is a preferable form. The total thickness means a total thickness including all layers such as a base film, a pressure-sensitive adhesive layer, and other layers.

<Separator>

In the pressure-sensitive adhesive sheet of the present invention, it is preferable that a separator is adhered to the surface of the pressure-sensitive adhesive layer opposite to the surface in contact with the base film. The separator can be bonded to the surface of the pressure-sensitive adhesive layer in order to protect the pressure-sensitive adhesive surface, if necessary.

As a material constituting the separator, there are a paper or a plastic film, but a plastic film is suitably used because of its excellent surface smoothness. The film is not particularly limited as long as it can protect the pressure-sensitive adhesive layer, and examples thereof include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, A polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, and an ethylene-vinyl acetate copolymer film.

The thickness of the separator is usually about 5 to 200 占 퐉, preferably about 10 to 100 占 퐉. Within this range, it is preferable that the bonding workability to the pressure-sensitive adhesive layer and the peeling workability from the pressure-sensitive adhesive layer are excellent. If necessary, the separator may be subjected to antistatic treatment such as release, antifouling, coating, kneading, and vapor deposition using a silicone, fluorine, long chain alkyl or fatty acid amide releasing agent or silica powder.

In the pressure-sensitive adhesive sheet of the present invention, it is preferable that the fluoric oligomer is present (coated and laminated) on the surface of the separator in contact with the pressure-sensitive adhesive layer (see FIG. When the separator is adhered to the pressure sensitive adhesive layer by the presence of the fluorinated oligomer on the surface of the separator in contact with the pressure sensitive adhesive layer, the fluorinated oligomer is transferred (transferred) from the surface of the separator to the pressure sensitive adhesive layer surface , The adhesive layer is bonded to an adherend (for example, a polarizing plate) or the like. Thereafter, a light-releasing effect by the low surface free energy of the fluorine portion and a function as a tackifier resin, It is possible to achieve slippage (displacement), restraint of lifting or peeling (both re-peeling and stickiness), and more preferable form.

&Lt; Optical member &

It is preferable that the optical member of the present invention is adhered (protected) by the adhesive sheet or, when the separator is attached, by a pressure-sensitive adhesive sheet from which the separator is peeled. Since the pressure-sensitive adhesive sheet has excellent curl control properties and light fastness properties, it can be used for a surface protection application (surface protective film) such as at the time of processing, transportation, shipping, etc. Therefore, in order to protect the surface of the optical member , It becomes useful.

[Example]

Hereinafter, some embodiments related to the present invention will be described, but the present invention is not intended to be limited to those shown in these embodiments. In the following description, &quot; part &quot; and &quot;% &quot; are on a mass basis unless otherwise specified. In addition, the amount (added amount) in the table is shown.

Each characteristic in the following description was measured or evaluated as follows.

&Lt; Measurement of weight average molecular weight (Mw)

The weight-average molecular weight (Mw) of the polymer or the like to be used was measured using a GPC (HLC-8220GPC) manufactured by Tosoh Corporation. The measurement conditions are as follows.

Sample concentration: 0.2 mass% (THF solution)

Sample injection volume: 10 μl

Eluent: THF

Flow rate: 0.6 ml / min

Measuring temperature: 40 ° C

column:

Sample column; TSKguardcolumn SuperHZ-H (1) + TSKgel SuperHZM-H (2)

Reference column; TSKgel SuperH-RC (1)

Detector: Differential refractometer (RI)

In addition, the weight average molecular weight was determined in terms of polystyrene conversion. In measuring the number average molecular weight (Mn), the same measurements as the weight average molecular weight (Mw) were also made.

&Lt; Bubble Diary of Pressure-Sensitive Adhesive Composition (Solution) >

After mixing and stirring the pressure-sensitive adhesive composition (solution) of each example, the bubble diary of the pressure-sensitive adhesive composition (solution) was visually observed. In the evaluation, the case where the bubble diary was not confirmed, the case where the bubble diary was confirmed a little, and the case where the bubble diary was clearly confirmed was evaluated as x.

<Shear force>

The surface protective film was cut into a size of 10 mm in width and 100 mm in length and the separator was peeled off, (N / cm 2) at a tensile rate of 0.06 mm / min at 23 ° C in a TAC polarizing plate (SEG1423DU polarizer, width: 25 mm, length: 100 mm, manufactured by Nitto Denko Corporation) Shear force.

The surface protective film of the present invention preferably has a shearing force of 5 N / cm 2 or more, preferably 5 to 50 N / cm 2, at 23 ° C × 50% RH on the polarizing plate of the pressure- , And more preferably 7 to 40 N / cm &lt; 2 &gt;. By adjusting the shearing force to 5 N / cm 2 or more, it is possible to suppress slippage (slippage), lifting and peeling after adhesion to an adherend, and excellent curl controllability and a favorable form.

<Measurement of Peeling Voltage>

The pressure-sensitive adhesive sheet 1 of each example was cut into a size of 70 mm in width and 130 mm in length and a release liner (separator) was peeled off and then a polarizing plate (SEG1423DU polarizer, Nitto Denko Corporation, , Length: 100 mm) 20, and one end of the pressure-sensitive adhesive sheet 1 was evaced 30 mm from the end of the polarizing plate 20, and pressed with a hand roller.

The sample was allowed to stand for one day under an environment of 23 캜 x 50% RH, and then set at a predetermined position on a sample holding table 30 having a height of 20 mm as shown in Fig. The end portion of the pressure-sensitive adhesive sheet (surface protective film) 1, which had been evacuated from the polarizing plate 20 by 30 mm, was fixed to an automatic winder (not shown) and peeled off at a peeling angle of 150 ° and a peeling rate of 30 m / min. The electric potential of the surface of the adherend (polarizing plate 20) generated at this time is measured by a potential meter 40 (type "STATIRON DZ-4" manufactured by Shishi Seidenk Co., Ltd.) fixed at a position 30 mm high from the center of the polarizer 20 Quot ;, &quot; peeling electrification voltage &quot; was measured. The measurement was carried out in an environment of 23 캜 and 50% RH.

The peeling electrification voltage (kV) (absolute value) in the present invention is preferably 1.0 or less, more preferably 0.5 or less, and still more preferably 0.3 or less. Within the above range, the antistatic property and the peeling electrification property are excellent, and the workability is excellent, which is a preferable form.

&Lt; Contamination (resistance to contamination) >

The pressure-sensitive adhesive sheet for each example was cut into a size of 50 mm in width and 80 mm in length, and the separator was peeled off. Then, air bubbles were applied to a TAC polarizing plate (SEG1423DU polarizer, width: 70 mm, length: 100 mm, manufactured by Nitto Denko Corporation) And an evaluation sample was prepared. After the evaluation sample was allowed to stand under the environment of 70 캜 for 120 hours, the pressure-sensitive adhesive sheet was peeled from the adherend by hand, and the bubble marks on the surface of the adherend were visually observed. In the evaluation, the case where the bubble mark was not confirmed was marked with o, and the case where the bubble mark was confirmed was marked by x.

&Lt; Measurement of low speed peeling force &

The surface protective film was cut into a width of 25 mm and a length of 100 mm after being left under the environment of 23 占 폚 and 50% RH for 24 hours. A TAC polarizing plate (SEG1423DU polarizer, width: 70 mm, length: 100 mm) Pressure of 0.3 m / min to prepare an evaluation sample. After leaving the laminate for 30 minutes under an environment of 23 ° C × 50% RH, the low-speed peeling force (N / 25 mm) at the time of peeling at a peeling speed of 0.3 m / min (slow peeling) and a peeling angle of 180 ° in a universal tensile tester ) Were measured. The measurement was carried out in an environment of 23 캜 x 50% RH.

The surface protective film of the present invention is characterized in that the 180 ° peel adhesion force (tensile rate 0.3 m / min: low peel force) at 23 ° C × 50% RH to the polarizer of the pressure-sensitive adhesive layer used in the surface protective film is 0.15 N / More preferably 0.01 to 0.15 N / 25 mm, and even more preferably 0.02 to 0.14 N / 25 mm. By adjusting the peel adhesion force (tensile speed 0.3 m / min) to 0.15 N / 25 mm or less, the peeling operation becomes easy (re-peeling property) when the surface protective film becomes unnecessary, And it becomes a preferable form.

&Lt; Preparation of acrylic polymer (1)

96 parts by mass of 2-ethylhexyl acrylate (2EHA), 4 parts by mass of 2-hydroxyethyl acrylate (HEA), and 2 parts by mass of a polymerization initiator were added to a four-necked flask equipped with a stirrer, a thermometer, , 0.2 part by mass of 2'-azobisisobutylonitrile and 150 parts by mass of ethyl acetate were introduced into a flask, and nitrogen gas was introduced while slowly stirring. The polymerization reaction was carried out for 6 hours while maintaining the liquid temperature in the flask at around 65 ° C, (1) solution (40 mass%). The weight average molecular weight (Mw) of the acrylic polymer (1) was 560,000.

&Lt; Preparation of acrylic polymer (2) >

91 parts by mass of 2-ethylhexyl acrylate (2EHA), 9 parts by mass of 4-hydroxybutyl acrylate (4HBA), and 4 parts by mass of acrylic acid (AA) were added to a four- necked flask equipped with a stirrer, a thermometer, , 0.2 part by mass of 2,2'-azobisisobutyronitrile as a polymerization initiator, and 150 parts by mass of ethyl acetate were fed into a flask, and nitrogen gas was introduced while stirring slowly. The liquid temperature in the flask was maintained at about 65 DEG C Hour polymerization reaction was carried out to prepare an acrylic polymer (2) solution (40 mass%). The weight average molecular weight (Mw) of the acrylic polymer (2) was 560,000.

&Lt; Production of acrylic polymer (3) >

98.5 parts by mass of 2-ethylhexyl acrylate (2EHA), 1.5 parts by mass of 4-hydroxybutyl acrylate (4HBA), and 2 parts by mass of a polymerization initiator were added to a four-necked flask equipped with a stirrer, a thermometer, , 0.2 part by mass of 2'-azobisisobutylonitrile and 150 parts by mass of ethyl acetate were introduced into a flask, and nitrogen gas was introduced while slowly stirring. The polymerization reaction was carried out for 6 hours while maintaining the liquid temperature in the flask at around 65 ° C, (3) solution (40 mass%). The weight average molecular weight (Mw) of the acrylic polymer (3) was 550,000.

&Lt; Example 1 >

[Preparation of acrylic pressure-sensitive adhesive solution]

A solution of the acrylic polymer (1) (40% by mass) was diluted with ethyl acetate to 20% by mass and 500 parts by mass (solid content 100 parts by mass) of a fluoric oligomer (Megaface F- 0.5 parts by mass (solids content: 0.05 parts by mass) of a solution diluted with ethyl 10%, 5 parts by mass (solids content: 0.5 parts by mass) of a solution obtained by diluting LiTFSI with 10% by mass of ethyl acetate as an ionic compound and 3 parts by mass of a trifunctional isocyanate compound 3 parts by mass (solids content: 3 parts by mass) of isocyanurate of hexamethylene diisocyanate (CORONATE HX manufactured by TOSOH CORPORATION), 3 parts by mass of dibutyltin dilaurate (1% by mass ethyl acetate solution) 0.03 parts by mass) was further added and mixed and stirred to prepare an acrylic pressure-sensitive adhesive solution.

[Preparation of anti-static film]

An antistatic agent solution was prepared by diluting 10 parts by mass of an antistatic agent (manufactured by Sorbex, Micro Solvor RMd-142, tin oxide and polyester resin as main components) with a mixed solvent containing 30 parts by mass of water and 70 parts by mass of methanol .

The obtained antistatic agent solution was coated on a polyethylene terephthalate (PET) film (thickness: 38 mu m) using a Meyer bar and dried at 130 DEG C for 1 minute to remove the solvent to form an antistatic layer (thickness: 0.2 mu m) To prepare an antistatic film.

[Preparation of pressure-sensitive adhesive sheet (surface protective film)]

The acrylic pressure-sensitive adhesive solution was coated on the surface opposite to the antistatic treatment surface of the antistatic treatment film and heated at 130 占 폚 for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 15 占 퐉. Subsequently, a siliconized surface of a polyethylene terephthalate film (thickness: 25 占 퐉) subjected to a silicon treatment on one side was bonded to the surface of the pressure-sensitive adhesive layer to produce a pressure-sensitive adhesive sheet.

&Lt; Examples 2 to 12 >

A pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1, depending on the raw materials and blending amounts shown in Table 1.

&Lt; Example 13 >

[Preparation of urethane pressure-sensitive adhesive solution]

As a polyol, 85 parts by weight of a polyol having three hydroxyl groups, Prinin S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), a polyol Sanennix GP3000 (manufactured by Sanyo Chemical Industries, Ltd., Mn = 3000) , 2 parts by mass of a polyol having three hydroxyl groups (Mn = 1000, manufactured by Sanyo Chemical Industries, Ltd.) and 18 parts by mass of an isocyanate compound (Coronate HX: C / HX, manufactured by Nippon Polyurethane Co., Ltd.) as a crosslinking agent , 0.04 part by mass of iron (III) acetylacetonato (manufactured by Tokyo Kasei Kogyo Co., Ltd.) as a catalyst, 0.2 parts by mass of Megaface F-562 of fluoric oligomer (manufactured by DIC Corporation) (EMITFSI, manufactured by Tokyo Kasei Kogyo Co., Ltd.) and 210 parts by mass of ethyl acetate as a diluting solvent were blended to obtain a urethane pressure-sensitive adhesive solution. Then, in the same manner as in Example 1, a pressure-sensitive adhesive sheet was prepared in which the heating conditions and the like and the thickness of the obtained pressure-sensitive adhesive layer were adjusted.

&Lt; Example 14 >

[Preparation of silicone-based pressure-sensitive adhesive solution]

100 parts by mass of solid content of "X-40-3229" (solid content 60% by mass, manufactured by Shinetsu Chemical Co., Ltd.) as a silicone adhesive, "CAT-PL-50T" (manufactured by Shinetsu Chemical Industries, 0.5 part by mass of a fluorinated oligomer, 0.2 part by mass of Megaface F-562 (manufactured by DIC Corporation), and 1 part by mass of 1-ethyl-3-methylimidazolium tri (fluoromethanesulfonyl) imide (EMITFSI, 1 part by mass, manufactured by Kassei Kogyo Co., Ltd.) and 100 parts by mass of toluene as a solvent were blended to obtain a silicone pressure-sensitive adhesive solution. Then, in the same manner as in Example 1, a pressure-sensitive adhesive sheet was prepared in which the heating conditions and the like and the thickness of the obtained pressure-sensitive adhesive layer were adjusted.

&Lt; Comparative Examples 1 to 3 >

A pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1, depending on the raw materials and blending amounts shown in Table 1.

Table 1 and Table 2 show the results of the formulation, various measurements and evaluations of the pressure-sensitive adhesive sheets of Examples and Comparative Examples. The compounding amounts in Table 1 indicate the active ingredients. The abbreviations in Table 1 are described below.

[Fluorine oligomer]

F-562: fluoric oligomer, weight average molecular weight 27900, manufactured by DIC, trade name: Megaface F-562

F-558: fluoric oligomer, weight average molecular weight: 11900, manufactured by DIC, trade name: Megaface F-558

F-569: fluoric oligomer, weight average molecular weight 6920, manufactured by DIC, trade name: Megaface F-569

222F: Fluorine oligomer, weight average molecular weight 2940, manufactured by Neos, trade name: Fotogen 222F

[An oxyalkylene group-containing compound]

PD-420: an oxyalkylene group-containing compound (HLB value: 12.6) containing no organopolysiloxane, manufactured by Kao Corporation, trade name: Latemul PD-420

KF-353: an organopolysiloxane containing an oxyalkylene chain, manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KF-353

[Ionic Compound]

LiTFSI: Lithium bis (trifluoromethanesulfonyl) imide, manufactured by Tokyo Kasei Kogyo Co., Ltd.

Bu ₃ MePTFSI: tributyl methylphosphonium bis (trifluoromethanesulfonyl) imide, manufactured by Tokyo Kasei Kogyo Co.,

X-40-2450: Silicon containing ionic group, manufactured by Shinetsu Chemical Co., Ltd.

BMPTFSI: 1-butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) imide, manufactured by Wako Pure Chemical Industries,

MTOATFSI: methyl trioctylammonium bis (trifluoromethanesulfonyl) imide, manufactured by Tokyo Kasei Kogyo Co.,

EMITFSI: 1-ethyl-3-methylimidazolium tri (fluoromethanesulfonyl) imide, manufactured by Tokyo Kasei Kogyo Co.,

From Table 2, it was confirmed that the shear force and the peeling electrification voltage were excellent in all Examples. Further, it was confirmed that when the blending amount of the fluoric oligomer was adjusted to 5.5 parts by mass or less, which is excellent in stain resistance to 100 parts by mass of the used polymer, the stain resistance (low staining property) was also excellent. Further, in the case of the example using the fluoric oligomer having a weight average molecular weight of 20,000 or more, it was confirmed that the bubble date of the pressure-sensitive adhesive composition (solution) can be suppressed.

On the other hand, from Table 2, it was confirmed that in Comparative Example 1, since the ionic compound was not compounded, the peeling electrification voltage was lowered, and in Comparative Example 2, the fluorine oligomer was not added. Further, in Comparative Example 3, since the fluorine oligomer having a weight average molecular weight of less than 3500 was used, it was confirmed that the shearing force was lowered. Further, in Comparative Example 3, since the fluorine oligomer 222F having a weight average molecular weight of less than 20,000 was used, the bubble date of the pressure-sensitive adhesive composition (solution) was confirmed.

The pressure-sensitive adhesive sheet disclosed herein can be used for protecting an optical member during manufacture, transport, etc. of an optical member used as a component of a liquid crystal display panel, a plasma display panel (PDP), an organic electroluminescence (EL) Is suitable as a surface protective film. In particular, a surface protective film (surface protective film for optical use) applied to an optical member such as a polarizing plate (polarizing film) for a liquid crystal display panel, a wavelength plate, a retardation plate, an optical compensation film, a brightness enhancement film, a light diffusion sheet, .

1: Pressure sensitive adhesive sheet
10: Glass plate
11: Separator
12: Fluorine-based oligomer coating film
13: Pressure-sensitive adhesive layer
14: base film
20: polarizer
30: Sample Stands
40: Potentiometer

Claims (7)

A pressure-sensitive adhesive polymer, a fluorinated oligomer having a weight average molecular weight of 3500 or more, and an ionic compound. The pressure-sensitive adhesive composition according to claim 1, which contains an oxyalkylene group-containing compound. The pressure-sensitive adhesive composition according to claim 1 or 2, wherein the pressure-sensitive adhesive polymer is at least one selected from the group consisting of a (meth) acrylic polymer, a urethane-based polymer and a silicone-based polymer. A pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition according to any one of claims 1 to 3,
Wherein the fluorine oligomer is present inside and / or on the surface of the pressure-sensitive adhesive layer. The pressure-sensitive adhesive sheet according to claim 4, wherein a separator is attached to a surface of the pressure-sensitive adhesive layer opposite to a surface contacting the base film. The pressure-sensitive adhesive sheet according to claim 5, wherein the fluoric oligomer is present on the surface of the separator which contacts the pressure-sensitive adhesive layer. An optical member characterized by having a pressure-sensitive adhesive sheet according to claim 4 or a pressure-sensitive adhesive sheet according to any one of claims 5 to 6, and a pressure-sensitive adhesive sheet having the separator peeled thereon.

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