JP6936009B2 - Polarizer - Google Patents

Description

The present invention relates to a polarizing plate with a surface protective film for a polarizing plate. In particular, the polarizing plate with a surface protective film can form an image display device such as a liquid crystal display device (LCD), an organic EL display device, a CRT, or a PDP, alone or as an optical film obtained by laminating them.

Due to the image forming method of a liquid crystal display device or an organic EL display device, for example, in a liquid crystal display device, it is indispensable to arrange a polarizing element in a liquid crystal cell, and a polarizing plate is generally attached. There is.

For example, in the manufacture of liquid crystal display panels, the polarizing plate attached to the liquid crystal cell is an adhesive that constitutes a surface protective film for the polarizing plate in order to prevent the occurrence of scratches and stains in processes such as processing and transportation. It is attached to the surface of the polarizing plate via the agent layer. However, this surface protective film is peeled off when it is no longer needed, but when it is peeled off, static electricity is generated, causing whitening of the liquid crystal panel and destruction of the tag, which causes problems. ..

In order to suppress the generation of such static electricity, an antistatic agent such as an alkali metal salt is blended in the pressure-sensitive adhesive layer, and attempts have been made to impart antistatic properties (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2009-251281

However, by blending an antistatic agent in the pressure-sensitive adhesive layer as in Patent Document 1, the adhesive strength based on the pressure-sensitive adhesive layer becomes insufficient, or the antistatic agent bleeds out and contaminates the surface of the polarizing plate. It is difficult to achieve both adhesive properties and stain resistance.

Further, in the polarizing plate after the surface protective film for the polarizing plate is peeled off, problems such as scratches may occur in the subsequent steps, and durability such as scratch resistance is required.

Therefore, in view of the above circumstances, as a result of diligent research, the present invention uses a polarizing plate with a surface protective film for a polarizing plate (polarizing plate) having a specific configuration (lamination order), whereby this polarizing plate can be used as a liquid crystal display device. When the surface protective film for polarizing plates is peeled off after being laminated (pasted) on, etc., it is possible to prevent whitening of panels such as liquid crystal display devices and destruction of tags, and it has excellent peeling antistatic properties and stain resistance. An object of the present invention is to provide an optical member with a surface protective film for a polarizing plate having excellent durability.

That is, the polarizing plate with a surface protective film of the present invention has a polarizer and a protective film for the polarizer on at least one surface of the polarizer, and is opposite to the surface of the protective film for the polarizer that comes into contact with the polarizer. A polarizing plate having an antistatic layer formed by an antistatic agent composition containing a conductive polymer on the side, a base material, and a pressure-sensitive adhesive layer on one side of the base film, of the base film. A polarizing plate with a surface protective film for a polarizing plate having an antistatic layer on the side opposite to the surface in contact with the pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer of the surface protective film for the polarizing plate is formed. The pressure-sensitive adhesive composition in which the surface protective film for a polarizing plate is laminated on the antistatic layer of the polarizing plate to form the pressure-sensitive adhesive layer is characterized in that it does not contain an antistatic component.

In the polarizing plate with a surface protective film of the present invention, at least one kind of protective film for a polarizer selected from the group consisting of (meth) acrylic resin, cyclic olefin resin, polyester resin, and polycarbonate resin. It is preferably formed of the above resin.

In the polarizing plate with a surface protective film of the present invention, it is preferable that the protective film for a polarizer has an ultraviolet absorbing function.

The polarizing plate with a surface protective film for a polarizing plate of the present invention is a surface protective film for a polarizing plate having an antistatic layer, a base film, and an adhesive layer formed of an antistatic composition containing no antistatic component. In addition, an antistatic layer formed of an antistatic agent composition containing a conductive polymer, a protective film for a polarizer, and a polarizing plate having a polarizing plate are included, and the surface protective film for the polarizing plate is interposed through an adhesive layer. By laminating the antistatic layer of the polarizing plate, a polarizing plate with a surface protective film for a polarizing plate (polarizing plate) having a specific configuration (stacking order) can be obtained, and this polarizing plate can be used as a liquid crystal display device (LCD) or the like. When the surface protective film for the polarizing plate is peeled off after being laminated (pasted) on the plate, the antistatic layer constituting the polarizing plate direction protective film and the antistatic layer constituting the polarizing plate are specifically positioned (laminated). By doing so, it is possible to prevent whitening of the panel of the liquid crystal display device) and the destruction of the tag, and it is excellent in antistatic property for peeling and is useful. Further, since the antistatic component is not (substantially) contained in the pressure-sensitive adhesive layer, contamination caused by the antistatic component in the pressure-sensitive adhesive layer can be prevented, and the stain resistance is excellent. By forming the antistatic layer with an antistatic agent composition containing a conductive polymer, it is possible to provide an optical member with a surface protective film for a polarizing plate having excellent flexibility and durability (scratch resistance). , Useful.

It is a schematic cross-sectional view which shows one structural example of the polarizing plate with the surface protection film for the polarizing plate which concerns on this invention. It is a schematic cross-sectional view which shows one structural example of the polarizing plate with the surface protection film for the polarizing plate which concerns on this invention. It is explanatory drawing which shows the measuring method of the peeling band voltage.

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

<Overall structure of polarizing plate with surface protective film for polarizing plate>
The polarizing plate with a surface protective film for a polarizing plate disclosed here is, for example, as shown in FIG. 1, the surface protective film 2 for a polarizing plate has an adhesive layer 12 on at least one side of the base film 11 and the other. The polarizing plate 3 has a structure in which the antistatic layer 10 is laminated on the surface, and the polarizing plate 3 is a surface in contact with the polarizing element protective film 21 on at least one surface of the polarizing element 22 and further on the polarizing element of the polarizer protective film 21. An example has a structure in which an antistatic layer 20 is laminated on the opposite surface. Further, as the polarizing plate surface protective film, a polarizing plate 1 with a polarizing plate surface protective film having a configuration in which the polarizing plate surface protective film is directly laminated (contacted) with the antistatic layer 20 of the polarizing plate 3 via an adhesive layer 20 is mentioned. Be done. Further, the polarizing plate with a surface protective film for a polarizing plate disclosed herein may be in the form of a roll or in the form of a single leaf.

<Base film for surface protection film for polarizing plate>
The surface protective film for a polarizing plate used in the present invention has a base film and an adhesive layer on one side of the base film, and antistatic is prevented on the side opposite to the surface of the base film in contact with the adhesive layer. It is characterized by having a layer. In the technique disclosed herein, the resin material constituting the base film can be used without particular limitation, and for example, transparency, mechanical strength, thermal stability, moisture shielding property, isotropic property, and the like are possible. It is preferable to use one having excellent properties such as flexibility and dimensional stability. In particular, since the base film has flexibility, the pressure-sensitive adhesive composition can be applied by a roll coater or the like, and can be wound into a roll shape, which is useful.

As the base film (base material, support), for example, a main resin component (main component among the resin components, typically 50 weight) is composed of a polyester polymer, a cellulose polymer, a polycarbonate polymer, an acrylic polymer and the like. A plastic film composed of a resin material containing% or more) can be preferably used as the base film. It may be a base film composed of a blend of two or more kinds of these polymers.

If necessary, the resin material constituting the base film may contain various additives such as an antioxidant, an ultraviolet absorber, a plasticizer, and a colorant (pigment, dye, etc.). For example, known or conventional surface treatments such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, acid treatment, alkali treatment, and undercoating may be applied. Such a surface treatment may be, for example, a treatment for enhancing the adhesion between the base film and the pressure-sensitive adhesive layer (the anchoring property of the pressure-sensitive adhesive layer).

As the surface protective film for a polarizing plate used in the present invention, it is also possible to use a plastic film having an antistatic treatment as the base film. It is preferable to use the base film because the charge of the polarizing plate surface protective film itself at the time of peeling can be suppressed. Further, the base film is a plastic film, and by applying an antistatic treatment to the plastic film, the charge of the surface protective film for a polarizing plate itself is reduced, and the antistatic ability to the adherend is excellent. can get. The method for imparting the antistatic function is not particularly limited, and a conventionally known method can be used. For example, an antistatic resin, a conductive polymer, or a conductive substance composed of an antistatic agent and a resin component can be used. Examples thereof include a method of applying the contained conductive resin, a method of depositing or plating a conductive substance, and a method of kneading an antistatic agent or the like.

The thickness of the base film is 50 μm or more, preferably 50 to 200 μm, more preferably 70 to 150 μm, and further preferably 75 to 130 μm. When the thickness of the base film is within the above range, the bonding workability when the surface protective film for the polarizing plate is bonded to the polarizing plate and the transportability after the bonding are improved, which is preferable.

<Adhesive layer of surface protective film for polarizing plate>
The pressure-sensitive adhesive layer constituting the surface protective film for a polarizing plate used in the present invention is formed of a pressure-sensitive adhesive composition, and the pressure-sensitive adhesive composition does not contain an antistatic component. The pressure-sensitive adhesive composition contains a pressure-sensitive adhesive polymer, and the pressure-sensitive adhesive polymer can be used without particular limitation as long as it has pressure-sensitive properties. As the pressure-sensitive adhesive composition, for example, an acrylic pressure-sensitive adhesive containing a (meth) acrylic-based polymer, a urethane-based pressure-sensitive adhesive containing a urethane-based polymer, a silicone-based pressure-sensitive adhesive containing a silicone-based polymer, and the like are used. It is particularly preferable to use an acrylic pressure-sensitive adhesive containing a (meth) acrylic-based polymer, particularly from the viewpoint of adhesiveness and transparency.

In the pressure-sensitive adhesive layer used in the present invention, it is preferable that the pressure-sensitive adhesive composition contains a cross-linking agent. Further, in the present invention, the pressure-sensitive adhesive composition can be used to form a pressure-sensitive adhesive layer. For example, when the pressure-sensitive adhesive composition is an acrylic pressure-sensitive adhesive containing the (meth) acrylic polymer, the constituent units, the constituent ratios, the selection and addition ratio of the cross-linking agent, etc. of the (meth) acrylic polymer are appropriately selected. By adjusting and cross-linking, an adhesive layer (surface protective film for a polarizing plate) having more excellent heat resistance can be obtained.

As the cross-linking agent, an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative, a metal chelate compound and the like may be used, and the use of an isocyanate compound is particularly preferable. Further, these compounds may be used alone or in combination of two or more.

Further, the pressure-sensitive adhesive composition may contain other known additives, such as cross-linking catalysts, lubricants, colorants, powders such as pigments, plasticizers, pressure-sensitive adhesives, and low molecular weight polymers. , Surface lubricants, leveling agents, antioxidants, corrosion inhibitors, light stabilizers, UV absorbers, polymerization inhibitors, silane coupling agents, inorganic or organic fillers, metal powders, particulates, foils Etc. can be appropriately added depending on the intended use.

The pressure-sensitive adhesive composition is characterized by not containing an antistatic component, but "does not contain an antistatic component" means that it does not substantially contain an antistatic component and has an antistatic function. It means an adhesive layer that does not exhibit (for example, the surface resistance value of the surface of the adhesive layer is 10 ¹³ or more). When the pressure-sensitive adhesive composition contains an antistatic component, contamination is usually caused by the transfer of the antistatic component from the pressure-sensitive adhesive layer, but the pressure-sensitive adhesive layer used in the present invention has the pressure-sensitive adhesive composition. Since the substance does not substantially contain an antistatic component, this contamination can be prevented, the stain resistance is excellent, and this is a preferable embodiment.

<Antistatic layer of surface protective film for polarizing plate>
The surface protective film for a polarizing plate used in the present invention has a base film and an adhesive layer on one side of the base film, and is on the side opposite to the surface of the base film in contact with the adhesive layer. It is characterized by having an antistatic layer. By providing the antistatic layer on the outermost layer (back surface of the base film) of the surface protective film for the polarizing plate, the grounding effect is exhibited, the peeling antistatic property is excellent, and this is a preferable embodiment.

In order to form the antistatic layer, it is preferable that the base film is subjected to antistatic treatment. As the antistatic treatment, a general antistatic treatment method can be used, and the antistatic treatment is not particularly limited, but for example, an antistatic layer is provided on the back surface of the base film (the surface opposite to the adhesive layer). A method or the like can be used.

As a method of providing the antistatic layer, an antistatic agent or an antistatic resin containing an antistatic agent and a resin component, a conductive resin composition containing a conductive substance and a resin component, or a conductive polymer is used as a base material. Examples thereof include a method of applying to a film and a method of depositing or plating a conductive substance.

The antistatic agent is a cationic antistatic agent having a cationic functional group such as a quaternary ammonium salt or a pyridinium salt (for example, a primary amino group, a secondary amino group, a tertiary amino group, etc.); Anionic antistatic agents having anionic functional groups such as salts, sulfate esters, phosphonates, phosphates and the like; amphoteric ionic antistatic agents such as alkylbetaine and its derivatives, imidazoline and its derivatives, alanin and its derivatives. Agents; Nonion-type antistatic agents such as aminoalcohol and its derivatives, glycerin and its derivatives, polyethylene glycol and its derivatives; Examples thereof include an ionic conductive polymer obtained by polymerizing or copolymerizing a monomer having an ionic conductive group.

Specifically, as the cationic antistatic agent, a quaternary ammonium group such as an alkyltrimethylammonium salt, an acyloylamide propyltrimethylammonium metosulfate, an alkylbenzylmethylammonium salt, choline acyl chloride, or polydimethylaminoethyl methacrylate is used. Examples thereof include (meth) acrylate copolymers, styrene-based copolymers having a quaternary ammonium group such as polyvinylbenzyltrimethylammonium chloride, and diallylamine copolymers having a quaternary ammonium group such as polydiallyldimethylammonium chloride. Examples of the anionic antistatic agent include alkyl sulfonates, alkyl benzene sulfonates, alkyl sulfates, alkyl ethoxysulfate, alkyl phosphates, sulfonic acid group-containing styrene-based copolymers and the like. Examples of the zwitterionic antistatic agent include alkyl betaine, alkyl imidazolium betaine, and carbobetaine graft copolymer. Examples of the nonionic antistatic agent include fatty acid alkylolamide, di- (2-hydroxyethyl) alkylamine, polyoxyethylene alkylamine, fatty acid glycerin ester, polyoxyethylene glycol fatty acid ester, sorbitan fatty acid ester, and polyoxysorbitan fatty acid. Examples thereof include esters, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl ethers, polyethylene glycols, polyoxyethylene diamines, copolymers composed of polyethers, polyesters and polyamides, and methoxypolyethylene glycol (meth) acrylates.

Examples of the conductive polymer include polyaniline, polypyrrole, polythiophene and the like.

Examples of the conductive substance include tin oxide, antimony oxide, indium oxide, cadmium oxide, titanium oxide, zinc oxide, indium, tin, antimony, gold, silver, copper, aluminum, nickel, chromium, titanium, iron, cobalt, and iodine. Examples include copper chemicals and alloys or mixtures thereof.

As the resin component, a general-purpose resin such as polyester, acrylic, polyvinyl, urethane, melamine, and epoxy is used. When the antistatic agent is a polymer type antistatic agent, the antistatic resin does not have to contain the resin component. Further, the antistatic resin may contain a methylolized or alkylolized melamine-based compound, a urea-based compound, a glioxal-based compound, an acrylamide-based compound, an epoxy-based compound, or an isocyanate-based compound as a cross-linking agent.

As a method of forming by applying the antistatic layer, the antistatic resin, the conductive polymer, and the conductive resin composition are diluted with a solvent such as an organic solvent or water or a dispersion medium, and the coating liquid is used as a base film. Examples include a method of applying and drying. Examples of the organic solvent include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, methanol, ethanol, n-propanol, isopropanol and the like. These can be used alone or in combination of two or more. As the coating method, a known coating method is used, and specific examples thereof include a roll coating, a gravure coating, a reverse coating, a roll brush, a spray coating, an air knife coating, an impregnation and a curtain coating method.

The thickness of the antistatic layer (antistatic resin layer, conductive polymer layer, conductive resin composition layer) formed by the coating is preferably 0.001 to 5 μm, more preferably 0.005 to 1 μm. ..

Examples of the method of vapor deposition or plating of the conductive substance include vacuum vapor deposition, sputtering, ion plating, chemical vapor deposition, spray thermal decomposition, chemical plating, and electroplating.

The thickness of the antistatic layer (conductive substance layer) formed by the vapor deposition or plating is preferably 20 to 10000 Å (0.002 to 1 μm), more preferably 50 to 5000 Å (0.005 to 0.5 μm). be.

<Surface protective film for polarizing plate>
The surface protective film for a polarizing plate used in the present invention has a base film and an adhesive layer on one side of the base film, and is antistatic on the side opposite to the surface of the base film in contact with the adhesive layer. Although it is characterized by having a layer, as a method of forming a pressure-sensitive adhesive layer by cross-linking the pressure-sensitive adhesive composition, it is generally performed after application of the pressure-sensitive adhesive composition, but adhesion after cross-linking. It is also possible to transfer the pressure-sensitive adhesive layer made of the agent composition 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 applied to the base film, and a polymerization solvent or the like is dried and removed to form the pressure-sensitive adhesive layer. It is produced by forming it on a base film. After that, curing may be performed for the purpose of adjusting the component transfer of the pressure-sensitive adhesive layer, adjusting the cross-linking reaction, and the like. Further, when the pressure-sensitive adhesive composition is applied onto the base film to prepare a surface protective film for a polarizing plate, a solvent other than the polymerization solvent is contained in the pressure-sensitive adhesive composition so that the pressure-sensitive adhesive composition can be uniformly applied on the base film. One or more solvents may be newly added.

Further, as a method for forming the pressure-sensitive adhesive layer when manufacturing the surface protective film for a polarizing plate used in the present invention, a known method used for manufacturing pressure-sensitive adhesive tapes is used. Specific examples thereof include a roll coat, a gravure coat, a reverse coat, a roll brush, a spray coat, an air knife coat method, and an extrusion coat method using a die coater or the like.

The surface protective film for a polarizing plate used in the present invention is usually produced so that the thickness of the pressure-sensitive adhesive layer is about 3 to 100 μm, preferably about 5 to 50 μm. When the thickness of the pressure-sensitive adhesive layer is within the above range, it is easy to obtain an appropriate balance between removability and adhesiveness, which is preferable.

The surface protective film for a polarizing plate used in the present invention preferably has a total thickness of 5 to 300 μm, more preferably 10 to 200 μm, and most preferably 12 to 100 μm. When it is within the above range, it is excellent in adhesive properties (removability, adhesiveness, etc.), workability, and appearance characteristics, and is a preferable embodiment. The total thickness means the total thickness including all layers such as the base film, the pressure-sensitive adhesive layer, the antistatic layer, and other layers.

The surface protective film for a polarizing plate disclosed herein may be implemented in an embodiment including a base film, an adhesive layer, and an antistatic layer, as well as other layers. Examples of the other layer include an antistatic layer and an undercoat layer (anchor layer) that enhances the anchoring property of the pressure-sensitive adhesive layer.

<Polarizer>
The polarizing plate used in the present invention has a polarizer and a protective film for a polarizer on at least one surface of the polarizer, and a conductive polymer is provided on the side of the protective film for the polarizer that is opposite to the surface in contact with the polarizer. It is characterized by having an antistatic layer formed by an antistatic agent composition containing. Further, a structure in which a pressure-sensitive adhesive layer is laminated on at least one surface of the polarizing plate can be used, and another optical member (for example, an optical member (for example,) is used on the surface of the pressure-sensitive adhesive layer opposite to the surface in contact with the polarizing plate. A retardation film, a liquid crystal display device, etc.) can be laminated. The antistatic layer located on the surface layer of the polarizing plate and the pressure-sensitive adhesive layer constituting the surface protective film for the polarizing plate are directly laminated (contacted) with each other.

<Polarizer>
As the polarizer used in the present invention, one using a polyvinyl alcohol-based resin is used. Examples of the polarizer include a hydrophilic polymer film such as a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, and an ethylene-vinyl acetate copolymerization system partially saponified film, and a bicolor property of iodine or a bicolor dye. Examples thereof include a uniaxially stretched film by adsorbing a substance, a polyene-based oriented film such as a dehydrated product of polyvinyl alcohol and a dehydrogenated product of polyvinyl chloride. Among these, a polarizer made of a polyvinyl alcohol-based film and a dichroic substance such as iodine is preferable.

The polarizer in which the polyvinyl alcohol-based film is dyed with iodine and uniaxially stretched can be produced, for example, by dyeing the polyvinyl alcohol by immersing it in an aqueous solution of iodine and stretching it to 3 to 7 times the original length. .. If necessary, boric acid, zinc sulfate, zinc chloride and the like may be contained, or the mixture may be immersed in an aqueous solution such as potassium iodide. Further, if necessary, the polyvinyl alcohol-based film may be immersed in water and washed with water before dyeing. In addition to being able to clean the surface of the polyvinyl alcohol film and blocking inhibitors by washing the polyvinyl alcohol film with water, it also has the effect of preventing non-uniformity such as uneven dyeing by swelling the polyvinyl alcohol film. be. Stretching may be performed after dyeing with iodine, stretching while dyeing, or stretching and then dyeing with iodine. It can be stretched even in an aqueous solution such as boric acid or potassium iodide or in a water bath.

The thickness of the polarizer can be appropriately determined, but is preferably 30 μm or less, more preferably 28 μm or less, still more preferably 5 to 25 μm. Such a polarizer has little unevenness in thickness, is excellent in thin layer property and visibility, and has little dimensional change, so that it is excellent in durability against thermal shock.

The polarizer has an optical characteristic represented by a simple substance transmittance T and a degree of polarization P of the following equation P>-(100.929T-42.4-1) × 100 (however, T <42.3), or , P ≧ 99.9 (however, T ≧ 42.3). A polarizer configured to satisfy the above conditions primarily has the performance required for a display for a liquid crystal television using a large display element. Specifically, the contrast ratio is 1000: 1 or more and the maximum brightness is 500 cd / m ² or more. As another use, for example, it is attached to the visible side of an organic EL cell.

<Protective film for polarizer>
The material constituting the protective film for a polarizer is not particularly limited, but a polymer (resin) having excellent transparency, mechanical strength, thermal stability, moisture blocking property, isotropic property, ultraviolet absorption and the like is preferable. For example, polyester-based polymers (polyester-based resins) such as polyethylene terephthalate and polyethylene naphthalate, (meth) acrylic-based polymers ((meth) acrylic-based resins) such as polymethylmethacrylate, polycarbonate-based polymers (polycarbonate-based resins), and the like can be mentioned. Be done. Further, polyethylene, polypropylene, polyolefin having a cyclo-based or norbornene structure (cyclic olefin-based resin) and the like are also mentioned as examples of polymers forming the protective film for a polarizer. Above all, it is preferable that the protective film for a polarizer is formed of at least one resin selected from the group consisting of a (meth) acrylic resin, a cyclic olefin resin, a polyester resin, and a polycarbonate resin. , It is particularly preferable to use a resin having an ultraviolet absorbing function. These protector films for the polarizer are usually attached to the polarizer by an adhesive layer.

In addition, one or more kinds of arbitrary suitable additives may be contained in the protective film for a polarizer. Examples of the additive include an ultraviolet absorber, an antioxidant, a lubricant, a plasticizer, a mold release agent, a color retardant, a flame retardant, a nucleating agent, an antistatic agent, a pigment, a colorant and the like. The content of the polymer in the protective film for a polarizer is preferably 50 to 100% by weight, more preferably 50 to 99% by weight, still more preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. .. When the content of the polymer in the protective film for a polarizer is 50% by weight or less, the high transparency inherent in the polymer may not be sufficiently exhibited.

The thickness of the protective film for a polarizer can be appropriately determined, but in general, it is preferably 100 μm or less, more preferably 80 μm or less, still more preferably 80 μm or less, from the viewpoints of workability such as strength and handleability, and thin layer property. Is preferably 10 to 60 μm.

A functional layer such as a hard coat layer, an antireflection layer, an anti-sticking layer, a diffusion layer or an anti-glare layer can be provided on the surface of the protective film for a polarizer to which the polarizer is not adhered. The functional layers such as the hard coat layer, the antireflection layer, the sticking prevention layer, the diffusion layer and the antiglare layer can be provided on the protector protective film itself, and are separately separated from the protector protective film. It can also be provided as a thing.

When laminating the polarizer and the protective film for the polarizer, an easy-adhesion layer can be provided between the protective film for the polarizer and the adhesive layer.

<Antistatic layer of polarizing plate>
The polarizing plate with a surface protective film for a polarizing plate of the present invention has a polarizer and a protective film for the polarizer on at least one surface of the polarizer, and a surface of the protective film for the polarizer that comes into contact with the polarizer. A polarizing plate having an antistatic layer formed of an antistatic agent composition containing a conductive polymer is provided on the opposite side, and the antistatic layer of the polarizing plate is interposed via an adhesive layer of the surface protective film for the polarizing plate. The surface protective film for the polarizing plate is laminated on the surface. Since the antistatic layer is an antistatic layer formed from an antistatic agent composition containing a conductive polymer, it is possible to suppress an increase in surface resistance even in a high temperature environment, and it is excellent in flexibility and durability. An antistatic layer is obtained, which is a preferred embodiment.
Further, by having the antistatic layer on the surface of the polarizing plate, it is not necessary to impart antistatic properties to the pressure-sensitive adhesive layer constituting the surface protective film for the polarizing plate which is directly laminated (contacted) with the antistatic layer. That is, since it is not necessary to add an antistatic component, it is preferable because it has excellent stain resistance and good appearance. In particular, by blending the polyaniline sulfonic acid and the polythiophenes doped with the polyonions within the above range, the polyaniline sulfonic acid alone or the polythiophenes doped with the polyonions can be used alone. It is presumed that the reason why the stability of antistatic property in a high temperature environment is improved as compared with the case of blending is as follows. In polythiophenes doped with polyanions, polythiophenes are coordinated with anionic groups of polyanions to form a complex, and the conductive mechanism thereof is the intramolecular conductivity of polythiophenes occurring in the complex, polythiophenes. Intermolecular conductivity and conductivity between composite structures are known. Here, the conductivity between the complex structures is a rate-determining process because the distance between the molecules is large. By using polyaniline sulfonic acid, which is higher than polythiophenes, in combination, polyaniline sulfonic acid connects the complex consisting of polythiophenes and polyanions, and since it itself has conductivity, the conductivity between the complexes can be improved. It is presumed that it has been enhanced, the antistatic property has been improved, and the stability in a high temperature environment has been increased, which makes it extremely useful as a polarizing plate. Further, when the polyaniline sulfonic acid is used alone as the conductive polymer, the initial conductivity is low, so that the peeling zone voltage and the surface resistance value with time are likely to increase.
Further, when the polythiophenes doped with the polythiophenes are used alone, the initial conductivity is high, but the polyanions (corresponding to the dopant) are more easily desorbed from the polythiophenes over time, so that they are exfoliated over time. It is not preferable because the voltage band and the surface resistance value are likely to increase.

<Conductive polymer>
The antistatic layer is preferably formed of an antistatic agent composition containing polyaniline sulfonic acid and polythiophenes doped with polyonions as a conductive polymer component. By combining the conductive polymers, polyaniline sulfonic acid is responsible for the conductivity between the core-shell structures of polythiophenes / polyanions, as compared with the case where they are individually blended. It is useful because it can stabilize the properties and antistatic properties in a high temperature environment.

The content of the conductive polymer is preferably 1 to 90% by weight, more preferably 5 to 80% by weight, still more preferably 10 to 70% by weight, based on all the components contained in the antistatic layer. Most preferably, it is 20 to 50% by weight. If the content of the conductive polymer is too small, the antistatic effect may be small, and if the content of the conductive polymer is too large, the adhesion of the antistatic layer to the base material (protective film for a polarizer). It is not preferable because there is a risk that the film will drop or the transparency will decrease.

Polyaniline sulfonic acid used as the conductive polymer component has a weight average molecular weight in terms of standard polystyrene measured by gel permeation chromatography (GPC) (Mw) is preferably at 5 × 10 ⁵ or less, 3 × 10 ⁵ or less is more preferable. The weight average molecular weight of these conductive polymers is usually preferably 1 × 10 ³ or more, and more preferably 5 × 10 ³ or more.

Examples of commercially available products of the polyaniline sulfonic acid include the trade name "aqua-PASS" manufactured by Mitsubishi Rayon Co., Ltd.

Examples of polythiophenes used as the conductive polymer component include polythiophene, poly (3-methylthiophene), poly (3-ethylthiophene), poly (3-propylthiophene), poly (3-butylthiophene), and poly. (3-Hexylthiophene), Poly (3-Heptylthiophene), Poly (3-octylthiophene), Poly (3-decylthiophene), Poly (3-dodecylthiophene), Poly (3-octadecylthiophene), Poly (3) -Bromothiophene), poly (3-chlorothiophene), poly (3-iodothiophene), poly (3-cyanothiophene), poly (3-phenylthiophene), poly (3,4-dimethylthiophene), poly (3) , 4-dibutylthiophene), poly (3-hydroxythiophene), poly (3-methoxythiophene), poly (3-ethoxythiophene), poly (3-butoxythiophene), poly (3-hexyloxythiophene), poly (3-hexyloxythiophene) 3-Heptyloxythiophene), Poly (3-octyloxythiophene), Poly (3-decyloxythiophene), Poly (3-dodecyloxythiophene), Poly (3-octadecyloxythiophene), Poly (3,4-dihydroxy) Thiophen), poly (3,4-dimethoxythiophene), poly (3,4-diethoxythiophene), poly (3,4-dipropoxythiophene), poly (3,4-dibutoxythiophene), poly (3, 4-dihexyloxythiophene), poly (3,4-diheptyloxythiophene), poly (3,4-dioctyloxythiophene), poly (3,4-didecyloxythiophene), poly (3,4-didodecyl). Oxythiophene), poly (3,4-ethylenedioxythiophene), poly (3,4-propylenedioxythiophene), poly (3,4-butenedioxythiophene), poly (3-methyl-4-methoxythiophene) ), Poly (3-methyl-4-ethoxythiophene), Poly (3-carboxythiophene, Poly (3-methyl-4-carboxythiophene), Poly (3-methyl-4-carboxyethylthiophene), Poly (3- Methyl-4-carboxybutylthiophene) may be mentioned. These may be used alone or in combination of two or more. Among them, poly (3,4-ethylenedi) may be used from the viewpoint of conductivity. Oxythiophene) (PEDOT) is preferred.

The polythiophenes have a degree of polymerization of preferably 2 to 1000, more preferably 5 to 100. When it is within the above range, it is preferable because it is excellent in conductivity.

The polyanions are polymers of structural units having anionic groups and serve as dopants for polythiophenes. Examples of the polyanions include polystyrene sulfonic acid, polyvinyl sulfonic acid, polyallyl sulfonic acid, polyacrylic sulfonic acid, polymethacrylsulfonic acid, poly (2-acrylamide-2-methylpropanesulfonic acid), polyisoprenesulfonic acid, and poly. Sulfoethyl methacrylate, poly (4-sulfobutyl methacrylate), polymetallicyloxybenzene sulfonic acid, polyvinylcarboxylic acid, polystyrene carboxylic acid, polyallylcarboxylic acid, polyacrylic carboxylic acid, polymethacrylcarboxylic acid, poly (2-acrylamide- 2-Methylpropanecarboxylic acid), polyisoprenecarboxylic acid, polyacrylic acid, polysulfonated phenylacetylene and the like. These homopolymers may be used, or two or more kinds of copolymers may be used. Of these, polystyrene sulfonic acid (PSS) is preferable.

The polyanions have a weight average molecular weight (Mw) of preferably 10 to 1,000,000, more preferably 2000 to 500,000. When it is within the above range, it is preferable because it is excellent in doping and dispersibility to polythiophenes.

Examples of commercially available products of polythiophenes doped with the polyanions include poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (PEDOT / PSS), trade name "Bytron P" manufactured by BAYER, Shin-Etsu. Examples thereof include the product name "Sepruzida" manufactured by Polymer Co., Ltd., the product name "Verazol" manufactured by Soken Kagaku Co., Ltd., and the product name "Denatoron P-502RG" manufactured by Nagase ChemteX Corporation. Above all, when PEDOT / PSS is used for the antistatic layer constituting the polarizing plate, the generation of contamination is suppressed as compared with the case where the antistatic component is used for the adhesive layer constituting the surface protective film for the polarizing plate. Since PEDOT / PSS is a conductive polymer and has excellent stain resistance, an antistatic layer having excellent flexibility and durability can be obtained, which is a preferable embodiment.

In the antistatic agent composition, the blending ratio (weight ratio) of the polyaniline sulfonic acid and the polythiophenes doped with the polyanilines (the polyaniline sulfonic acid: the polythiophenes doped with the polyanions) is It is preferably 90:10 to 10:90, more preferably 85:15 to 15:85, and even more preferably 80:20 to 20:80. Within the above range, the surface resistance value can be suppressed to a low level, and the stability of the surface resistance value in a high temperature environment is particularly excellent, which is a preferable embodiment. If the content of the polyaniline sulfonic acid is low, or if the content of the polythiophenes doped with the polyanions is low, the surface resistance value in a high temperature environment tends to increase, which is not preferable.

<Binder>
The antistatic layer can contain a binder component and can be used without particular limitation, but an antistatic layer containing a polyester resin as a binder in order to impart solvent resistance, mechanical strength, antistatic properties, and thermal stability. It is preferably formed by the agent composition. The polyester resin is preferably a resin material containing polyester as a main component (typically, a component that exceeds 50% by weight, preferably 75% by weight or more, for example, 90% by weight or more). The polyester is typically a polyvalent carboxylic acid having two or more carboxyl groups in one molecule (typically a dicarboxylic acid) and a derivative thereof (anhydride, esterified product, halogen of the polyvalent carboxylic acid). Select from one or more compounds (polycarboxylic acid component) selected from compounds (such as compounds) and polyhydric alcohols (typically diols) having two or more hydroxyl groups in one molecule. It is preferable to have a structure in which one kind or two or more kinds of compounds (polyvalent alcohol components) are condensed.

Examples of compounds that can be adopted as the polyvalent carboxylic acid component include oxalic acid, malonic acid, difluoromalonic acid, alkylmalonic acid, succinic acid, tetrafluorosuccinic acid, alkylsuccinic acid, (±) -apple acid, and meso. -Tartrate acid, itaconic acid, maleic acid, methylmaleic acid, fumaric acid, methylfumaric acid, acetylenedicarboxylic acid, glutaric acid, hexafluoroglutaric acid, methylglutaric acid, glutaconic acid, adipic acid, dithioadipic acid, methyladipic acid, dimethyl Adipic acid, tetramethyladipic acid, methyleneadipic acid, muconic acid, galactalic acid, pimelic acid, suberic acid, perfluorosveric acid, 3,3,6,6-tetramethylsveric acid, azelaic acid, sebacic acid, perfluoro Aliphatic dicarboxylic acids such as sebacic acid, brassic acid, dodecyldicarboxylic acid, tridecyldicarboxylic acid, tetradecyldicarboxylic acid; cycloalkyldicarboxylic acid (eg, 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid), Alicyclic dicarboxylic acids such as 1,4- (2-norbornene) dicarboxylic acid, 5-norbornene-2,3-dicarboxylic acid (hymic acid), adamantandicarboxylic acid, spiroheptandicarboxylic acid; phthalic acid, isophthalic acid, dithio Isophthalic acid, methylisophthalic acid, dimethylisophthalic acid, chloroisophthalic acid, dichloroisophthalic acid, terephthalic acid, methylterephthalic acid, dimethylterephthalic acid, chloroterephthalic acid, bromoterephthalic acid, naphthalenedicarboxylic acid, oxofluorangecarboxylic acid, anthracendicarboxylic acid , Biphenyldicarboxylic acid, biphenylenedicarboxylic acid, dimethylbiphenylenedicarboxylic acid, 4,4 "-p-terephenylenedicarboxylic acid, 4,4" -p-quarelphenyldicarboxylic acid, bibenzyldicarboxylic acid, azobenzenedicarboxylic acid, homophthalic acid , Phenylene diacetic acid, phenylenedipropionic acid, naphthalenedicarboxylic acid, naphthalenedipropionic acid, biphenyldiacetic acid, biphenyldipropionic acid, 3,3'-[4,4'-(methylenedi-p-biphenylene) dipropionic acid, Aromatic dicarboxylic acids such as 4,4'-bibenzyldiacetic acid, 3,3'(4,4'-bibenzyl) dipropionic acid, oxydi-p-phenylene diacetic acid; the acid of any of the polyvalent carboxylic acids described above. Anhydrous; the es of any of the polyvalent carboxylic acids mentioned above Tel (eg alkyl ester). It can be a monoester, a diester, or the like. ); An acid halide corresponding to any of the above-mentioned polyvalent carboxylic acids (for example, dicarboxylic acid chloride); and the like.

Preferable examples of the compound that can be adopted as the polyvalent carboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid and their acid anhydrides; adipic acid, sebacic acid, azelaic acid, and succinic acid. With aliphatic dicarboxylic acids such as fumaric acid, maleic acid, hymic acid, 1,4-cyclohexanedicarboxylic acid and acid anhydrides thereof; and lower alkyl esters of the dicarboxylic acids (for example, monoalcohol having 1 to 3 carbon atoms). Esther) and the like.

On the other hand, examples of compounds that can be adopted as the polyhydric alcohol component include ethylene glycol, propylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, and 1,4-butanediol. , Neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 3-methylpentanediol, diethylene glycol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 2-methyl- Diols such as 1,3-propanediol, 2,2-diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, xylylene glycol, hydrogenated bisphenol A, and bisphenol A. Can be mentioned. Other examples include alkylene oxide adducts of these compounds (eg, ethylene oxide adducts, propylene oxide adducts, etc.).

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

Commercially available products of the polyester resin include, for example, the trade names of Byronal MD-1100, MD-1200, MD-1245, MD-1335, MD-1480, MD-1500, MD-1930, MD-1985, MD manufactured by Toyobo Co., Ltd. -2000, trade name of GOO CHEMICAL CO., LTD. Plus Coat Z-221, Z-446, Z-561, Z-565, Z-880, Z-3310, RZ-105, RZ-570, Z-730, Z -760, Z-592, Z-687, Z-690, pesresin A-110, A-120, A-124GP, A-125S, A-160P, A-520, A-613D, A manufactured by Takamatsu Oil & Fat Co., Ltd. Examples thereof include -615GE, A-640, A-645GH, A-647GEX, A-680, A-684G, WAC-14, WAC-17XC and the like.

The antistatic layer is a resin other than a polyester resin (for example, an acrylic resin or an acrylic-urethane resin) as a binder as long as the performance of the polarizing plate disclosed herein (for example, the performance such as antistatic property) is not significantly impaired. , Acrylic-styrene resin, acrylic-silicone resin, silicone resin, polysilazane resin, fluororesin, styrene resin, alkyd resin, urethane resin, amide resin, polyolefin resin, etc. It is also possible to use it. When the above resins are used in combination, an antistatic layer in which the ratio of the polyester resin to the binder is 51 to 100% by weight is preferable. The proportion of the binder in the entire antistatic layer can be, for example, 50 to 95% by weight, and usually 60 to 90% by weight is appropriate.

<Glidant>
The antistatic agent composition used for forming the antistatic layer in the technique disclosed herein is composed of a group consisting of a fatty acid amide, a fatty acid ester, a silicone-based lubricant, a fluorine-based lubricant, and a wax-based lubricant as lubricants. It is a preferred embodiment to use at least one selected. An embodiment in which the surface of the antistatic layer is not further peeled (for example, a treatment of applying a known peeling agent such as a silicone-based release agent or a long-chain alkyl-based release agent and drying it) by using the lubricant. In this case as well, an antistatic layer having both sufficient slipperiness and print adhesion can be obtained, which can be a preferable embodiment. Such an embodiment in which the surface of the antistatic layer is not further peeled can prevent whitening caused by the peeling agent (for example, whitening due to storage under heating and humidifying conditions). It is preferable in that. It is also advantageous in terms of solvent resistance.

Specific examples of the fatty acid amide include lauric acid amide, partimate amide, stearic acid amide, behenic acid amide, hydroxystearic acid amide, oleic acid amide, erucic acid amide, N-oleyl partimate amide, and N-stearyl stealic acid. Amide, N-stearyl oleic acid amide, N-oleyl stealic acid amide, N-stearyl erucate amide, methylol stealic acid amide, methylene bisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, ethylene bisstearic acid Amide, ethylene bishydroxystearic acid amide, ethylene bisbechenic acid amide, hexamethylene bisstearic acid amide, hexamethylene bisbechenic acid amide, hexamethylene hydroxystearic acid amide, N, N'-distearyl adipate amide, N, N ´-Distearyl sevacinic acid amide, ethylene bisoleic acid amide, ethylene biserucate amide, hexamethylene bisoleic acid amide, N, N ′-diorail adipate amide, N, N ′ -diorail sevacinic acid amide, m Examples thereof include -xylylene bisstearic acid amide, m-xylylene bishydroxystearic amide, and N, N'-stearyl isophthalic acid amide. One of these lubricants may be used alone, or two or more of these lubricants may be used in combination.

Specific examples of the fatty acid ester include polyoxyethylene bisphenol A laurate ester, butyl stearate, 2-ethylhexyl palmitate, 2-ethylhexyl stearate, monoglyceride behenate, cetyl 2-ethylhexanoate, isopropyl myristate, and palmitin. Isopropyl acid, cholesteryl isostearate, lauryl methacrylate, methyl coconut fatty acid, methyl laurate, methyl oleate, methyl stearate, myristyl myristate, octyldodecyl myristate, pentaerythritol monooleate, pentaerythritol monostearate, pentaerythritol Examples thereof include tetrapalmitate, stearyl stearate, isotridecyl stearate, triglyceride 2-ethylhexanoate, butyl laurate, and octyl oleate. One of these lubricants may be used alone, or two or more of these lubricants may be used in combination.

Specific examples of the silicone-based lubricant include polydimethylsiloxane, polyether-modified polydimethylsiloxane, amino-modified polydimethylsiloxane, epoxy-modified polydimethylsiloxane, carbinol-modified polydimethylsiloxane, mercapto-modified polydimethylsiloxane, and carboxyl-modified polydimethyl. Siloxane, methylhydrogen silicone, methacryl-modified polydimethylsiloxane, phenol-modified polydimethylsiloxane, silanol-modified polydimethylsiloxane, aralkyl-modified polydimethylsiloxane, fluoroalkyl-modified polydimethylsiloxane, long-chain alkyl-modified polydimethylsiloxane, higher fatty acid-modified ester Examples thereof include modified polydimethylsiloxane, higher fatty acid amide-modified polydimethylsiloxane, and phenyl-modified polydimethylsiloxane. One of these lubricants may be used alone, or two or more of these lubricants may be used in combination.

Specific examples of the fluorine-based lubricant include perfluoroalkanes, perfluorocarboxylic acid esters, fluorine-containing block copolymers, and polyether polymers having an alkyl fluoride group. One of these lubricants may be used alone, or two or more of these lubricants may be used in combination.

Specific examples of the wax-based lubricant include petroleum-based wax (paraffin wax, etc.), plant-based wax (carnauba wax, etc.), mineral-based wax (montan wax, etc.), higher fatty acid (cerotic acid, etc.), and triglyceride (palmitin). Various waxes such as acid triglyceride) can be mentioned. One of these lubricants may be used alone, or two or more of these lubricants may be used in combination.

The proportion of the lubricant in the entire antistatic layer can be 1 to 50% by weight, and usually 5 to 40% by weight is appropriate. If the content of the lubricant is too small, the slipperiness tends to decrease. If the content of the lubricant is too large, the print adhesion and the back surface peeling force (adhesive force) may decrease.

The antistatic agent composition forming the antistatic layer is at least one selected from the group consisting of a silane coupling agent, an epoxy-based cross-linking agent, a melamine-based cross-linking agent, and an isocyanate-based cross-linking agent as the cross-linking agent. It is preferably contained, and in particular, it is preferable to use the melamine-based cross-linking agent and / or the isocyanate-based cross-linking agent. When forming the antistatic layer, the conductive polymer component (for example, polythiophenes doped with polyaniline sulfonic acid or polyanions) can be immobilized in the binder, and has excellent water resistance and solvent resistance, and further, print adhesion. It is possible to realize effects such as improvement of. In particular, the use of a melamine-based cross-linking agent improves water resistance and solvent resistance, and the use of an isocyanate-based cross-linking agent improves water resistance and print adhesion. , Water resistance, solvent resistance, and print adhesion are improved, which is useful.

As the melamine-based cross-linking agent, melamine, alkylated melamine, methylol melamine, alkoxylated methyl melamine and the like can be used.

Further, as the isocyanate-based cross-linking agent, it is preferable to use a blocked isocyanate-based cross-linking agent that is stable even in an aqueous solution. Specific examples of the blocked isocyanate-based cross-linking agent include alcohols, phenols, thiophenols, amines, and imides as isocyanate-based cross-linking agents that can be used in the preparation of general pressure-sensitive adhesive layers and antistatic layers. , Oxims, lactams, active methylene compounds, mercaptans, imines, ureas, diaryl compounds, and those blocked with sodium bicarbonate and the like can be used.

The antistatic layer in the technique disclosed herein includes an antistatic agent, an antioxidant, a coloring agent (pigment, dye, etc.), a fluidity adjusting agent (thixotropic agent, thickener, etc.), and a film-forming agent, if necessary. It may contain additives such as auxiliaries, surfactants (antifoamers, etc.), preservatives and the like. Further, it is also possible to contain a glycidyl compound, a polar solvent, a polyhydric aliphatic alcohol, a lactam compound and the like as a conductivity improver.

<Formation of antistatic layer>
The antistatic layer is a liquid composition (coating material for forming an antistatic layer, antistatic agent composition) in which an additive used according to the conductive polymer component or the like is dissolved or dispersed in an appropriate solvent (water or the like). It can be suitably formed by a method including applying a substance to a substrate (protective film for a polarizer). For example, a method of applying the coating material to one side of a base material (protective film for a polarizer), drying it, and performing a curing treatment (heat treatment, ultraviolet treatment, etc.) as necessary can be preferably adopted. The NV (nonvolatile content) of the coating material can be, for example, 5% by weight or less (typically 0.05 to 5% by weight), and usually 1% by weight or less (typically 0.10 to 0% by weight). 1% by weight) is appropriate. When forming an antistatic layer having a small thickness, it is preferable that the NV of the coating material is, for example, 0.05 to 0.50% by weight (for example, 0.10 to 0.40% by weight). By using the low NV coating material in this way, a more uniform antistatic layer can be formed.

As the solvent constituting the coating material for forming the antistatic layer, a solvent capable of stably dissolving or dispersing the forming component of the antistatic layer is preferable. Such a solvent can be an organic solvent, water, or a mixed solvent thereof. Examples of the organic solvent include esters such as ethyl acetate; ketones such as methyl ethyl ketone, acetone and cyclohexanone; cyclic ethers such as tetrahydrofuran (THF) and dioxane; aliphatic or alicyclic ethers such as n-hexane and cyclohexane. Hydrocarbons; aromatic hydrocarbons such as toluene and xylene; aliphatic or alicyclic alcohols such as methanol, ethanol, n-propanol, isopropanol and cyclohexanol; alkylene glycol monoalkyl ethers (eg ethylene glycol monomethyl ethers) , Ethylene glycol monoethyl ether), glycol ethers such as dialkylene glycol monoalkyl ether; etc .; one or more selected from the above can be used. In a preferred embodiment, the solvent of the coating material is water or a mixed solvent containing water as a main component (for example, a mixed solvent of water and ethanol).

Further, in order to improve the dispersion stability in a solvent, it is possible to include a basic organic compound capable of coordinating or binding as an ion pair to the anion group of polyanions. Examples of the basic organic compound include known amine compounds, hydrochlorides of amine compounds, cationic emulsifiers, and basic resins.

Specific examples of the basic organic compound include methyloctylamine, methylbenzylamine, N-methylaniline, dimethylamine, diethylamine, diethanolamine, N-methylethanolamine, di-n-propylamine, diisopropylamine, and methyl-. Isopropanolamine, dibutylamine, di-2-ethylhexylamine, aminoethylethanolamine, 3-amino-1-propanol, isopropylamine, monoethylamine, 2-ethylhexylamine, t-butylamine, N- (2-aminoethyl)- 3-Aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, Amine compounds such as 3-aminopropyltriethoxysilane and N-phenyl-3-aminopropyltrimethoxysilane, hydrochlorides of primary amines such as monomethylamine, monoethylamine and stearylamine, dimethylamine, diethylamine, distearylamine and the like. Secondary amine hydrochloride, tertiary amine hydrochloride such as trimethylamine, triethylamine, stearyldimethylamine, quaternary ammonium salt such as stearyltrimethylammonium chloride, distearyldimethylammonium chloride, stearyldimethylbenzylammonium chloride, monoethanolamine , Ethanolamine hydrochlorides such as diethanolamine and triethanolamine, and polyethylenepolyamine hydrochlorides such as ethylenediamine and diethylenetriamine.

Specific examples of the cationic emulsifier include alkylammonium salts, alkylamide betaines, and alkyldimethylamine oxides.

Specific examples of the basic resin include polyester-based, acrylic-based, and urethane-based polymer copolymers having a weight average molecular weight (Mw) of 10 to 1,000,000. If the weight average molecular weight of the basic resin is less than 1000, sufficient steric hindrance may not be obtained and the dispersion effect may be reduced, and even if the weight average molecular weight is larger than 1,000,000, an aggregating action may occur.

The amine value of the basic resin is preferably 5 to 200 mgKOH / g. If it is less than 5 mgKOH / g, the interaction with the polyanions doped in polythiophenes tends to be insufficient, and a sufficient dispersion effect may not be obtained. On the other hand, when the amine value of the basic resin exceeds 200 mgKOH / g, the number of steric hindrance layers is reduced as compared with the affinity portion for polythiophenes doped with polythiophenes, and the dispersion effect may be insufficient.

Examples of the basic resin include Solspire17000, Solspire20000, Solspire24000, Solspire32000 (manufactured by Zeneca Co., Ltd.), Disperbyk-160, Disperbyk-161, Disperbyk-162, Disperbyk-163, Disperbyk-163, Disperbyk-170. (Made by Big Chemie), Ajispar PB711, Ajispar PB821, Ajispar PB822, Ajisper PB824 (manufactured by Ajinomoto Co., Inc.), Epomin 006, Epomin 012, Epomin 018 (manufactured by Nippon Shokubai Co., Ltd.), EFKA4046, EFKA4300, EFKA4330, EFKA45 , Disparon DA-400N (manufactured by Kusumoto Kasei Kagaku Co., Ltd.), etc., which can be used alone or in combination. In particular, azisper PB821, azisper PB822, and azisper PB824 are preferable in terms of dispersibility and conductivity during use.

The content of the basic compound is not limited, but is preferably 1 part by weight to 100,000 parts by weight, more preferably 10 parts by weight to 10,000 parts by weight, based on 100 parts by weight of the total of polythiophenes and polyanions. Can be added in the range of

<Characteristics of antistatic layer>
The thickness of the antistatic layer (after heat stretching) is preferably 100 nm or less, more preferably 3 to 100 nm, and further preferably 20 to 80 nm. If the thickness of the antistatic layer is too small, it becomes difficult to form the antistatic layer uniformly (for example, the thickness of the antistatic layer varies greatly depending on the location), and therefore, the appearance of the polarizing plate is changed. Unevenness may be likely to occur. On the other hand, if it is too thick, it may affect the characteristics of the polarizing plate (optical characteristics, dimensional stability, etc.).

The surface resistance measured on the surface of the antistatic layer (Ω / □) is preferably 1.0 × 10 ⁸ or less, more preferably from ^{1.0 × 10 4 ~1.0 × 10 8} , more preferably from ^{1.0 × 10 6 ~1.0 × 10 7} . A polarizing plate showing a surface resistance value within the above range suppresses the charging of the surface protective film for a polarizing plate due to triboelectric charging generated in a processing process or a transporting process, and sucks dust or reduces workability. It becomes possible to prevent it, and it can be preferably used. The surface resistance value can be calculated from the surface resistance value measured in an atmosphere of a temperature of 23 ° C. and a humidity of 50% RH using a commercially available insulation resistance measuring device.

<First adhesive layer>
A structure in which a first pressure-sensitive adhesive layer is laminated on at least one surface of the polarizing plate can be used, and other optical members can be used on the surface of the front first pressure-sensitive adhesive layer opposite to the surface in contact with the polarizing plate. (For example, a retardation film, a liquid crystal display device, etc.) and the like can be laminated (see FIG. 2). An appropriate adhesive (adhesive composition) can be used for the first pressure-sensitive adhesive layer, and the type thereof is not particularly limited. As adhesives, rubber adhesives, acrylic adhesives, silicone adhesives, urethane adhesives, vinyl alkyl ether adhesives, polyvinyl alcohol adhesives, polyvinylpyrrolidone adhesives, polyacrylamide adhesives, Examples include cellulose-based adhesives. Among these adhesives (adhesive compositions), those having excellent optical transparency, exhibiting appropriate wettability, cohesiveness and adhesiveness, and excellent weather resistance and heat resistance are preferably used. NS. An acrylic pressure-sensitive adhesive is preferably used to exhibit such characteristics.

As a method of forming the first pressure-sensitive adhesive layer, for example, the pressure-sensitive adhesive (adhesive composition) is applied to a peel-treated separator, a polymerization solvent or the like is dried and removed to form a pressure-sensitive adhesive layer, and then a polarizing plate is formed. It is produced by a method of transferring to a polarizing plate, or a method of applying the pressure-sensitive adhesive to a polarizing plate and drying and removing a polymerization solvent or the like to form a pressure-sensitive adhesive layer on a polarizer. When applying the pressure-sensitive adhesive, one or more solvents other than the polymerization solvent may be newly added as appropriate. As the peeling-treated separator, a silicone separator is preferably used.

In the step of applying the adhesive (adhesive composition) on such a separator and drying it to form a pressure-sensitive adhesive layer, as a method of drying the pressure-sensitive adhesive, an appropriate and appropriate method may be used depending on the purpose. Can be adopted. Preferably, a method of heating and drying the coating film is used. The heat-drying temperature is preferably 40 to 200 ° C, more preferably 50 to 180 ° C, and particularly preferably 70 to 170 ° C. By setting the heating temperature in the above range, an adhesive layer having excellent adhesive properties can be obtained.

Various methods are used as a method for forming the pressure-sensitive adhesive layer. Specifically, for example, roll coat, kiss roll coat, gravure coat, reverse coat, roll brush, spray coat, dip roll coat, bar coat, knife coat, air knife coat, curtain coat, lip coat, die coater, etc. Examples include a method such as an extrusion coating method.

The thickness of the first pressure-sensitive adhesive layer is preferably 2 to 50 μm, more preferably 2 to 40 μm, and even more preferably 5 to 35 μm.

The separator can protect the first pressure-sensitive adhesive layer until it is put into practical use. Examples of the constituent material of the separator include plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester film, porous materials such as paper, cloth, and non-woven fabric, nets, foam sheets, metal foils, and laminates thereof. A thin leaf body or the like can be mentioned, but a plastic film is preferably used because of its excellent surface smoothness. The plastic film is not particularly limited as long as it can protect the pressure-sensitive adhesive layer, and for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, and vinyl chloride are all used. Examples thereof include polymer films, polyethylene terephthalate films, polybutylene terephthalate films, polyurethane films, and ethylene-vinyl acetate copolymer films.

The separator may be a silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based mold release agent, a mold release and antifouling treatment with silica powder, or the like, a coating type, a kneading type, a vapor deposition type, or the like, if necessary. Antistatic treatment can also be performed. In particular, the peelability from the first pressure-sensitive adhesive layer can be further enhanced by appropriately performing a peeling treatment such as a silicone treatment, a long-chain alkyl treatment, or a fluorine treatment on the surface of the release film.

The thickness of the separator is usually preferably 5 to 50 μm, more preferably 15 to 40 μm.

The polarizing plate disclosed herein may also include an antistatic layer, a protective film for a polarizer, a polarizing element, and an intervening layer (adhesive layer, first adhesive layer, etc.) and another layer. Can be carried out.

<Polarizing plate with surface protective film for polarizing plate>
In the polarizing plate with a surface protective film of the present invention, the polarizing plate and the surface protective film for the polarizing plate are attached to the antistatic layer of the polarizing plate via the pressure-sensitive adhesive layer of the surface protective film for the polarizing plate. The surface protective film for a polarizing plate is laminated. The polarizing plate with a surface protective film of the present invention has a specific configuration (lamination order), so that the polarizing plate is laminated (attached) to a liquid crystal display (LCD) or the like, and then the surface protective film for the polarizing plate is used. Since the antistatic layer that constitutes the polarizing plate direction protective film and the antistatic layer that constitutes the polarizing plate are in specific positions (in the order of lamination) when the polarizing plate is peeled off, whitening of panels such as liquid crystal displays and tags Can be prevented from being destroyed, and has excellent peeling antistatic property, which is useful. Further, since the adhesive layer does not use an antistatic component, it is excellent in stain resistance, and by having an antistatic layer constituting the polarizing plate, it is excellent in flexibility and durability (scratch resistance) and is useful. It becomes.

Hereinafter, some examples related to the present invention will be described, but the present invention is not intended to be limited to those shown in such specific examples. Unless otherwise specified, "parts" and "%" in the following description are based on weight. In addition, the blending amount (addition amount) in the table is shown.

In addition, each characteristic in the following description was measured or evaluated as follows. The methods for preparing the polarizing plate, the surface protective film for the polarizing plate, and the polarizing plate with the surface protective film for the polarizing plate described below were prepared according to the configurations and positional relationships shown in Table 1.

<Preparation of protective film for polarizer>
Acrylic resin (trade name: Acrypet VH, Tg: 113 ° C., manufactured by Mitsubishi Rayon Co., Ltd.) was vacuum dried at 100 ° C. to degas moisture and residual oxygen. A twin-screw extruder (equipment) in which a mixture of 100 parts by weight of degassed acrylic resin and 30 parts by weight of acrylic rubber (trade name: AR12, manufactured by Nippon Zeon Corporation) is added with nitrogen from the raw material hopper to the extruder. Name: TEM35B, manufactured by Toshiba Machine Co., Ltd., melted at a cylinder set temperature of 230 to 270 ° C., and pelletized to obtain raw material pellets. The obtained raw material pellets were vacuum dried at 100 ° C., and the raw material hopper to the extruder were supplied to a nitrogen-substituted single-screw extruder (device name: SE-65, manufactured by Toshiba Machine Co., Ltd.) to set a cylinder. It is melted at 230 to 270 ° C., passed through a coat hanger type T-die, cooled by a chrome-plated casting roll at 120 ° C. and a cooling chrome-plated casting roll at 90 ° C., and then cooled by a film winder. , An acrylic resin film (thickness: 40 μm), which is a protective film for a extruder, was obtained.

<Preparation of protective film for polarizer with antistatic layer (polymer type)>
Denatron P-502RG (containing PEDOT / PSS) manufactured by Nagase ChemteX Co., Ltd., which is an antistatic agent composition, is placed on an acrylic resin film (thickness: 40 μm), which is a protective film for a polarizer, and a wire bar # 6 is applied. After coating using the film, it was dried at 120 ° C. for 60 seconds to prepare a protective film for a polarizer with an antistatic layer (thickness of the antistatic layer: 80 nm). The surface resistance of the obtained antistatic layer surface was 3.12 × 10 ⁶ Ω / □.

<Preparation of protective film for polarizer with antistatic layer (metal type)>
On the acrylic resin film (thickness: 40 μm) which is the protective film for the polarizer, the tin oxide S-1 manufactured by Mitsubishi Materials Denshi Kasei Co., Ltd., which is an antistatic agent composition, is used on the wire bar # 6. After coating, the film was dried at 120 ° C. for 60 seconds to prepare a protective film for a polarizer with an antistatic layer (thickness of the antistatic layer: 80 nm). The surface resistance of the obtained antistatic layer surface was 1.21 × 10 ⁶ Ω / □.

<Making a polarizer>
60 μm-thick polyvinyl alcohol film (degree of polymerization: 2300, degree of saponification: 99.9%, width: 1000 mm, thickness: 75 μm, manufactured by Kuraray Co., Ltd .: VF-PS7500) in pure water at 30 ° C. It was stretched to a stretching ratio of 2.5 times while being immersed for seconds.
Then, it was stained in an aqueous iodine solution at 30 ° C. (weight ratio: pure water / iodine (I) / potassium iodide (KI) = 100/0.01/1) for 45 seconds.
Then, it was stretched in a 4 wt% boric acid aqueous solution so that the stretching ratio was 5.8 times. After stretching, the film was immersed in pure water for 10 seconds and then dried at 50 ° C. for 3 minutes while maintaining the tension of the film to obtain a polarizer. The thickness of this polarizer was 25 μm, and the water content was 14% by weight.

<Preparation of adhesive aqueous solution>
100 parts by weight of a polyvinyl alcohol-based resin containing an acetoacetyl group (average degree of polymerization: 1200, saponification degree: 98.5 mol%, acetoacetyl group modification degree: 5 mol%), 50 parts by weight of methylol melamine, pure water. An aqueous solution was prepared by dissolving in (water temperature: 30 ° C.) and adjusting the solid content concentration to 3.7% by weight. An aqueous adhesive solution was prepared by adding 18 parts by weight of an alumina colloidal aqueous solution (average particle size: 15 nm, solid content concentration: 10% by weight, positive charge) to 100 parts by weight of the aqueous solution. The viscosity of the aqueous adhesive solution was 9.6 mPa · s. The pH of the aqueous adhesive solution was in the range of 4 to 4.5. This was used as an aqueous adhesive solution.

<Antistatic layer of polarizing plate is laminated on the pressure-sensitive adhesive layer side of the surface protective film for polarizing plate (surface protective film side for polarizing plate)>
The surface of the protective film for a polarizer with an antistatic layer opposite to the antistatic layer is coated with the above-mentioned adhesive aqueous solution so that the thickness of the adhesive layer after drying is about 55 nm, and polarized light with an adhesive layer. A protective film for children was produced.
Then, under a temperature condition of 23 ° C., the protective film for a polarizer with an adhesive layer is brought into contact with one side of the polarizer, and the adhesive layer of the protective film for a polarizer with an adhesive layer is in contact with the polarizer. As described above, they were bonded together with a roll machine to form a laminated body. The laminate was dried at 70 ° C. for 10 minutes to prepare a polarizing plate (1).

<A polarizing plate of a polarizing plate is laminated on the pressure-sensitive adhesive layer side of a surface protective film for a polarizing plate (polarizer side)>
The adhesive aqueous solution was applied to the surface of the antistatic layer of the protective film for a polarizer with an antistatic layer so that the thickness of the adhesive layer after drying was about 55 nm to prepare a protective film with an adhesive layer. ..
Then, under a temperature condition of 23 ° C., the protective film for a polarizer with an adhesive layer is brought into contact with one side of the polarizer, and the adhesive layer of the protective film for a polarizer with an adhesive layer is in contact with the polarizer. As described above, they were bonded together with a roll machine to form a laminated body. The laminate was dried at 70 ° C. for 10 minutes to prepare a polarizing plate (2).

<Preparation of a polarizing plate in which a polarizing element protective film for a polarizing plate having no antistatic layer is laminated on the pressure-sensitive adhesive layer side of the surface protective film for a polarizing plate>
Compared to the protective film for a polarizer with an antistatic layer of the polarizing plate (1), the thickness of the adhesive layer after drying the aqueous adhesive solution on one side of the protective film for a polarizing element without an antistatic layer A protective film for a polarizer with an adhesive layer was prepared by applying the film so as to have a thickness of about 55 nm.
Then, under a temperature condition of 23 ° C., the protective film for a polarizer with an adhesive layer is brought into contact with one side of the polarizer, and the adhesive layer of the protective film for a polarizer with an adhesive layer is in contact with the polarizer. As described above, they were bonded together with a roll machine to form a laminated body. The laminate was dried at 70 ° C. for 10 minutes to prepare a polarizing plate (3).

<Surface protective film for polarizing plate to be used>
<E-MASK RP207>
As the surface protective film for the polarizing plate, the trade name "E-MASK RP207" manufactured by Nitto Denko KK, which has the configuration shown in Table 1, was used.

<AS3-830>
As the surface protective film for the polarizing plate, the trade name "AS3-830" manufactured by Fujimori Kogyo Co., Ltd. having the configuration shown in Table 1 was used.

<NSA35-H>
As the surface protective film for the polarizing plate, the trade name "Sanitect NSA35-H" manufactured by Sun A. Kaken Co., Ltd. having the configuration shown in Table 1 was used.

<Manufacturing a polarizing plate with a surface protective film for a polarizing plate>
The exposed surface of the antistatic layer of the polarizing plate (1) produced above, the exposed surface of the polarizer of the polarizing plate (2), or the polarizing plate without the antistatic layer (2). 3) The surface of the pressure-sensitive adhesive layer of the polarizing plate surface protective film is attached to the exposed surface of the polarizing element protective film with a roller, left at room temperature for 5 minutes, and with the polarizing plate surface protective film. A polarizing plate was produced.

<Measurement of surface resistance value on the surface of the antistatic layer of the polarizing plate>
The measurement was performed according to JIS-K-6911 using a resistivity meter (manufactured by Mitsubishi Chemical Analytical Co., Ltd., Hiresta UP MCP-HT450 type) in an atmosphere of a temperature of 23 ° C. and a humidity of 50% RH. The applied voltage was 100 V, and the surface resistance value was read 10 seconds after the start of measurement.
The surface resistance value (Ω / □) measured on the surface of the antistatic layer of the polarizing plate is a state in which the antistatic layer is formed after the antistatic agent composition (solution) is applied to the base film and dried. Measured at.

The surface resistivity measured at the surface of the antistatic layer of the present invention (Ω / □) is preferably 1.0 × 10 ⁸ or less, more preferably, 1.0 × ¹⁰ 4 ~1.0 × ¹⁰ it is ^8, more preferably ^{1.0 × 10 6 ~1.0 × 10 7} . The surface protective film for a polarizing plate having an antistatic layer showing a surface resistance value within the above range is a surface protective film used in the processing or transporting process of an article that dislikes static electricity, such as a liquid crystal cell or a semiconductor device. Can be suitably used as.

<Measurement of peeling band voltage (peeling antistatic property)>
As shown in FIG. 3, the polarizing plate surface protective film 2 according to each example is cut into a size of 70 mm in width and 130 mm in length, the release liner is peeled off from the surface of the pressure-sensitive adhesive layer, and then static elimination is performed in advance. Polarizing plate 3 (width: 70 mm, length: 100 mm) according to each example bonded to a plate 31 (manufactured by Mitsubishi Rayon Co., Ltd., trade name "Acrylite", thickness: 1 mm, width: 70 mm, length: 100 mm). One end of the surface protective film 2 for a polarizing plate protruded 30 mm from the end of the polarizing plate 20 on the surface, and the sample was pressure-bonded with a hand roller via an adhesive layer to prepare a sample.
This sample was left in an environment of 23 ° C. × 50% RH for one day, and then set in a predetermined position on a sample fixing table 30 having a height of 20 mm. The end portion of the surface protective film 1 protruding 30 mm from the polarizing plate 3 was fixed to an automatic winder (not shown) and peeled so as to have a peeling angle of 150 ° and a peeling speed of 30 m / min. The potential of the surface of the adherend (polarizing plate) generated at this time is fixed at a position 100 mm in height from the center of the polarizing plate 20 (manufactured by Kasuga Electric Co., Ltd., model “KSD-0103”). The stripping band voltage was measured at. The measurement was performed in an environment of 23 ° C. and 50% RH. When the polarizing plate did not have an antistatic layer, the potential on the surface of the protective film for the polarizer was measured as the peeling band voltage instead of the surface of the antistatic layer.

The peeling band voltage is a peeling band voltage mainly derived from the antistatic layer constituting the surface protective film for a polarizing plate of the present invention, and contributes to the peeling antistatic property.

The peeling band voltage (absolute value) of the surface protective film for a polarizing plate of the present invention is preferably 0.4 kV or less, and more preferably 0.3 kV or less. If the peeling band voltage exceeds 0.4 kV, the polarizer arrangement in the polarizing plate is disturbed, which is not preferable. As the evaluation in Table 1, the case of 0.4 kV or less was evaluated as ◯ (good), and the case of exceeding 0.4 kV was evaluated as × (poor).

<Stain resistance>
The surface of the pressure-sensitive adhesive layer of the surface protective film for the polarizing plate is attached to the surface of the antistatic layer of the polarizing plate, held at 70 ° C. for 120 hours, and then the surface protective film for the polarizing plate is peeled from the polarizing plate at a peeling speed of 30 m / min. The presence or absence of contamination on the surface of the polarizing plate was visually confirmed. If the surface of the polarizing plate to which the surface of the pressure-sensitive adhesive layer of the surface protective film for the polarizing plate is attached is not the antistatic layer but the protective film for the polarizer, visually check whether the surface of the protective film for the polarizer is contaminated. I confirmed it at.
As for the evaluation, the case where no contamination was observed was evaluated as ○ (good), and the case where contamination was observed was evaluated as × (inferior).

<Steel wool test (durability)>
Scratch resistance (durability) on the surface of the antistatic layer under the condition that steel wool (# 0000, manufactured by Nippon Steel Wool Co., Ltd.) is attached to a circular jig with a radius of 25 mm and the length is reciprocated 5 times with a load of 10 g. Gender) was evaluated. The case where the number of visually confirmed scratches was 10 or less was evaluated as ◯ (good), and the case where the number of scratches exceeded 10 was evaluated as × (inferior). If the surface of the polarizing plate to which the surface of the pressure-sensitive adhesive layer of the surface protective film for the polarizing plate is attached is not an antistatic layer, the durability has not been evaluated.

Table 1 shows the above-mentioned compounding contents and the results of various measurements and evaluations on the polarizing plates with a surface protective film for polarizing plates according to Examples and Comparative Examples.

注）表１中の「高分子タイプ」とは、帯電防止成分として、導電性高分子（ＰＥＤＯＴ／ＰＳＳ）を使用するものであり、金属タイプとは、帯電防止成分として、スズ系酸化物を使用するものである。
また、表１中の「偏光板用表面保護フィルム側」とは、偏光子とは反対側の帯電防止層の露出した表面に、偏光板用表面保護フィルムの粘着剤層表面が接触する場合を指す。
「偏光子側」とは、偏光子用保護フィルムとは反対側の偏光子の露出した表面に、偏光板用表面保護フィルムの粘着剤層表面が接触する場合を指す。
なお、偏光板の帯電防止層が存在しないため場合は、耐久性を評価をしていない。

Note) The "polymer type" in Table 1 uses a conductive polymer (PEDOT / PSS) as an antistatic component, and the metal type uses a tin oxide as an antistatic component. It is to be used.
Further, the “surface protective film side for polarizing plate” in Table 1 refers to the case where the surface of the pressure-sensitive adhesive layer of the surface protective film for polarizing plate comes into contact with the exposed surface of the antistatic layer on the side opposite to the polarizing element. Point to.
The “polarizer side” refers to a case where the surface of the pressure-sensitive adhesive layer of the surface protective film for a polarizing plate comes into contact with the exposed surface of the polarizer on the side opposite to the protective film for the polarizer.
If the antistatic layer of the polarizing plate does not exist, the durability has not been evaluated.

From Table 1, in Example 1, by having the antistatic layer at a specific position of the polarizing plate and the surface protective film for the polarizing plate, the antistatic property, the stain resistance, and the durability (scratch resistance) are improved. It was confirmed that it was excellent.

On the other hand, from Table 1, in the comparative example, in the case of the position of the antistatic layer constituting the polarizing plate and the absence of the antistatic layer constituting the polarizing plate or the surface protective film for the polarizing plate, the peeling antistatic property is inferior and the antistatic property is inferior. If the position of the antistatic layer constituting the polarizing plate is not in the desired position, the durability is inferior, and if the antistatic layer using a metal type antistatic component is also inferior in durability, it is used for the polarizing plate. It was confirmed that when the pressure-sensitive adhesive layer constituting the surface protective film contained an antistatic component, the stain resistance was inferior.

The surface protective film constituting the polarizing plate with a surface protective film disclosed herein is suitably used for a polarizing plate used as a component of a liquid crystal display panel, a plasma display panel (PDP), an organic electroluminescence (EL) display, or the like. be able to.

1: Polarizing plate with surface protective film for polarizing plate 2: Surface protective film for polarizing plate 3: Plate plate 10: Antistatic layer 11: Base film 12: Adhesive layer 20: Antistatic layer 21: Protective film for polarizer 22: Polarizer 23: First pressure-sensitive adhesive layer 24: Phase difference film 30: Sample fixing base 31: Acrylic plate 32: Potential measuring instrument

Claims (3)

An antistatic agent composition having a polarizer and a protective film for a polarizer on at least one surface of the polarizer and a conductive polymer on the side opposite to the surface of the protective film for the polarizer that comes into contact with the polarizer. A polarizing plate having an antistatic layer to be formed, and
It has a base film and a surface protective film for a polarizing plate having an adhesive layer on one side of the base film and an antistatic layer on the side opposite to the surface of the base film in contact with the adhesive layer. A polarizing plate with a surface protective film for a polarizing plate.
The surface protective film for the polarizing plate is laminated on the antistatic layer of the polarizing plate via the adhesive layer of the surface protective film for the polarizing plate.
The antistatic layer of the surface protective film for a polarizing plate does not contain an ionic compound, and does not contain an ionic compound.
The pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer contains an acrylic pressure-sensitive adhesive containing a (meth) acrylic-based polymer or a silicone-based pressure-sensitive adhesive containing a silicone-based polymer, and does not contain an antistatic component. A polarizing plate with a surface protective film for a polarizing plate. The protective film for a polarizer is formed of at least one resin selected from the group consisting of a (meth) acrylic resin, a cyclic olefin resin, a polyester resin, and a polycarbonate resin. The polarizing plate with a surface protective film for a polarizing plate according to claim 1. The polarizing plate with a surface protective film for a polarizing plate according to claim 1 or 2, wherein the protective film for a polarizer has an ultraviolet absorbing function.

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