KR20090082877A - Antistatic optical film, antistatic adhesive optical film, manufacturing method thereof, and image display device - Google Patents

Abstract

An antistatic optical film, an antistatic adhesive optical film, a manufacturing method thereof and an image display unit are provided to show an excellent re-working property. A method for manufacturing an antistatic optical film(1) comprises the following steps of: coating at least one surface of an optical film with a coating liquid containing water-soluble or water-dispersible conductive polymer and a binder; and drying the coating liquid to form an antistatic layer(2). A method for manufacturing an antistatic adhesive optical film comprises the following steps of: coating at least one surface of the optical film with the coating liquid containing water-soluble or water-dispersible conductive polymer and a binder; drying the coating liquid to forma the antistatic layer; and forming an adhesive layer(3) on the antistatic layer.

Description

Antistatic Optical Film, Antistatic Adhesive Optical Film, Manufacturing Method And Image Display Device {ANTISTATIC OPTICAL FILM, ANTISTATIC ADHESIVE OPTICAL FILM, MANUFACTURING METHOD THEREOF, AND IMAGE DISPLAY DEVICE}

The present invention relates to an antistatic optical film in which an antistatic layer is laminated on at least one surface of the optical film. The present invention also relates to an antistatic adhesive optical film in which an adhesive layer is laminated on an antistatic layer of the antistatic optical film. Furthermore, it relates to an image display device such as a liquid crystal display device, an organic EL display device and a PDP using the antistatic optical film and the antistatic adhesive optical film. Examples of the optical film may include a polarizing plate, a retardation plate, an optical compensation film, a brightness enhancement film, and a lamination thereof.

In a liquid crystal display or the like, it is indispensable to arrange polarizing elements on both sides of the liquid crystal cell from the image forming method, and in general, a polarizing plate is attached. In addition, various optical elements have been used for the liquid crystal panel to improve the display quality of the display in addition to the polarizing plate. For example, a retardation plate as color prevention, a viewing angle magnification film for improving the viewing angle of a liquid crystal display, and a brightness enhancement film for increasing the contrast of a display are used. These films are collectively called optical films.

These optical films are usually provided with a surface protective film on the surface of the optical film to prevent scratches or dirt on the surface of the optical film until transportation to the consumer. The surface protective film may be peeled off after being attached to an LCD or the like, or may be reattached to the same or different surface protective film after being peeled off once. Then, when the surface protective film is peeled off, static electricity is generated, and there is a problem that circuits such as LCD panels are destroyed by the static electricity. In addition, there is a problem that affects the array element inside the LCD panel, which in turn affects the alignment of the liquid crystal, causing a defect. In addition, the same problem occurs due to the friction between the optical films not only when the surface protective film is peeled off, but also depending on the manufacturing process or the method of use of the consumer. In order to solve the said problem, providing antistatic property to optical films, such as a polarizing plate, is proposed. For example, an optical film including an antistatic layer having an antistatic layer formed on a surface of an optical film, and a transparent conductive layer formed on one side or both sides of the optical film are disclosed.

On the other hand, an adhesive is usually used when adhering an optical film to a liquid crystal cell. In addition, since the adhesion between the optical film and the liquid crystal cell or the optical film usually reduces the loss of light, each material is in close contact using an adhesive. In this case, in view of having the advantage of not requiring a drying step for fixing the optical film, the pressure-sensitive adhesive is generally a pressure-sensitive adhesive optical film formed as a pressure-sensitive adhesive layer on one side of the optical film.

The adhesive optical film is cut into a display size when used. When the end part (cutting part) of an adhesive optical film contacts a person or an apparatus at the time of handling in such a use process, the adhesive missing may arise in the part. When the pressure-sensitive adhesive optical film in which the pressure-sensitive adhesive is dropped is attached to the liquid crystal cell, the missing part is not in close contact with each other, so that light is reflected from the part, resulting in display defects. In particular, in recent years, frame narrowing of the display proceeds, and the display quality is remarkably degraded by defects occurring at the ends. In addition, when the adhesive optical film is attached to the liquid crystal panel and then peeled off from the panel due to incorporation of foreign matter, the adhesive remains on the panel side (so-called adhesive residual phenomenon), i.e., rework It is desired that the properties be good.

It is also proposed to impart antistatic properties to the pressure-sensitive adhesive optical film. For example, electroconductive particle is included in the antiglare layer on the surface of a polarizing plate, imparting antistatic property to an antiglare layer, and the adhesive layer formed in the opposite surface is proposed (patent document 1). However, in the method of patent document 1, it is difficult to maintain the characteristic as an anti-glare layer, and stability is inferior. In addition, when the antistatic layer is formed on the pressure-sensitive adhesive optical film, it is preferable to form an antistatic layer between the optical film and the pressure-sensitive adhesive layer in order to eliminate the alignment failure of the liquid crystal cell generated by the application of the voltage generated inside the panel. Moreover, in the antistatic adhesive type optical film in which the antistatic layer was formed between the optical film and the adhesive layer, there existed a problem of adhesive missing, adhesive retention problem, or rework property. Moreover, as a method of providing an antistatic function to an optical film, the method of containing a conductive substance in an adhesive layer is proposed (patent document 2). However, in the method of patent document 2, it is difficult to maintain the characteristic as an adhesive layer, and stability is inferior.

[Patent Document 1] Japanese Patent Application Laid-Open No. 10-239521

[Patent Document 2] Japanese Unexamined Patent Publication No. 2003-294951

The present invention is an antistatic optical film in which an antistatic layer is laminated on at least one surface of an optical film, and the antistatic adhesive optical film having a pressure sensitive adhesive layer formed on the antistatic layer is less likely to have a tackiness and is less reworkable. It aims at providing this favorable thing. Moreover, it aims at providing these manufacturing methods. Furthermore, it aims at providing the image display apparatus using the antistatic optical film.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, the present inventors discovered the following antistatic optical film and antistatic adhesive optical film, and came to complete this invention.

That is, the present invention, in the antistatic optical film in which the antistatic layer is laminated on at least one surface of the optical film,

The antistatic layer relates to an antistatic optical film composed of a conductive polymer and a binder component which are water-soluble or water dispersible.

In the antistatic optical film, the conductive polymer that is water-soluble or water dispersible is preferably a polythiophene polymer.

In the antistatic optical film, the binder component is preferably at least one resin selected from the group consisting of polyurethane resins, polyester resins and acrylic resins.

In the antistatic optical film, the surface resistivity of the antistatic layer is preferably 1 × 10 ¹² Pa / s or less.

The present invention also relates to an antistatic adhesive optical film in which an adhesive layer is further laminated on a surface opposite to the optical film of the antistatic layer of the antistatic optical film.

In the antistatic pressure-sensitive adhesive optical film of the present invention, it was considered that the adhesion between the optical film and the pressure-sensitive adhesive layer due to the formation of the antistatic layer was mainly caused by the lack of pressure-sensitive adhesive and the rework from the liquid crystal panel. As a result, adhesiveness was improved by using the water-soluble or water-dispersible conductive polymer and binder component for an antistatic layer. As a result, when handling the antistatic adhesive optical film, it is possible to greatly reduce the adhesive residue during the rework from the liquid crystal panel or the partial adhesion of the adhesive to the contact of the film end, and thus the handling property of the antistatic adhesive optical film Can improve. In addition, since the antistatic layer is formed between the optical film and the pressure-sensitive adhesive layer, the antistatic effect is good, and it is possible to suppress the static electricity generated by the peeling of the surface protection film and the static electricity generated by the friction of the optical film. Misalignment of the liquid crystal can be prevented. In addition, the optical film and the pressure-sensitive adhesive layer can maintain their respective properties and excellent stability.

In the said antistatic adhesive optical film, it is preferable that an adhesive layer consists of an acrylic adhesive.

Moreover, this invention is a method of manufacturing the said antistatic optical film,

Production of an antistatic optical film comprising the step of applying a coating liquid containing a water-soluble or water-dispersible conductive polymer and a binder component to at least one surface of the optical film, and a step of drying the coating liquid to form an antistatic layer. It is about a method.

In addition, the present invention is a method for producing the antistatic adhesive optical film,

Applying a coating liquid containing a water-soluble or water-dispersible conductive polymer and a binder component to at least one surface of the optical film, drying the coating liquid to form an antistatic layer, and forming an adhesive layer on the antistatic layer It relates to a method for producing an antistatic adhesive optical film made of a step.

Conventionally, as a method of forming an antistatic layer on the surface of an optical film, a transparent conductive layer is formed by a vacuum deposition method, a sputtering method, an ion plating method, or the like, but these methods have high production costs and poor productivity. According to the manufacturing method of this invention, since an antistatic layer can be formed by coating methods, such as a coating, productivity is favorable.

The present invention also relates to an image display apparatus using the antistatic optical film or the antistatic adhesive optical film. The antistatic optical film and the antistatic adhesive optical film of the present invention are used in combination of one or a plurality of sheets according to various usage modes of an image display device such as a liquid crystal display device.

 According to the present invention, it is possible to provide an antistatic adhesive optical film, an antistatic adhesive optical film, a manufacturing method thereof, and an image display apparatus in which an adhesive delamination is less likely to occur and good rework property is achieved.

In the antistatic adhesive optical film of the present invention, as shown in FIG. 1, the antistatic layer 2 and the adhesive layer 3 are laminated on one surface of the optical film 1 in this order. In addition, although the case where the adhesive layer 3 is formed in one surface of the optical film 1 is shown in FIG. 1, the adhesive layer 3 may be in both surfaces of an optical film. You may have the antistatic layer 2 also about the adhesive layer 3 of another surface. In addition, the antistatic optical film of this invention is a case where it does not have the adhesive layer 3 in FIG.

The antistatic layer 2 of the antistatic adhesive optical film of the present invention contains a conductive polymer that is water-soluble or water dispersible as an antistatic agent, and further contains a binder component.

The conductive polymer that is water-soluble or water-dispersible has good stability at the time of heating and humidification of optical properties, appearance, antistatic effect and antistatic effect. Examples of the conductive polymer include polymers such as polyaniline, polythiophene, polypyrrole, and polyquinoxaline-based polymers. Among these, polyaniline, polythiophene, and the like, which are liable to become a water-soluble conductive polymer or a water-dispersible conductive polymer, are preferable. Used. In particular, polythiophene is preferable.

The water-soluble conductive polymer or the water-dispersible conductive polymer can be prepared by using the coating liquid for forming the antistatic layer as an aqueous solution or a water dispersion liquid, and the coating liquid does not need to use a non-aqueous organic solvent. It is because deterioration of a film base material can be suppressed. Moreover, it is preferable from an adhesive viewpoint that aqueous solution or water dispersion liquid uses only a solvent as water. In addition to water, an aqueous solvent may be contained in a hydrophilic solvent. For example, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-amyl alcohol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol, 1- Alcohol, such as ethyl-1- propanol, 2-methyl-1- butanol, n-hexanol, cyclohexanol, is mentioned.

It is preferable that the weight average molecular weight by polystyrene conversion of the said water-soluble or water-dispersible polyaniline is 500000 or less, More preferably, it is 300000 or less. It is preferable that the weight average molecular weight by polystyrene conversion of water-soluble or water-dispersible polythiophene is 400000 or less, More preferably, it is 300000 or less. When the weight average molecular weight exceeds the above value, the water-soluble or water dispersibility tends not to be satisfied, and when a coating liquid (aqueous solution or water dispersion) is prepared using such a polymer, solid content of the polymer remains in the coating liquid. It tends to be difficult to form an antistatic layer having a uniform or thick film thickness or high viscosity.

The water solubility of the water-soluble conductive polymer means that the solubility in 100 g of water is 5 g or more. It is preferable that the solubility with respect to 100 g of water of the said water-soluble conductive polymer is 20-30 g. The water-dispersible conductive polymer is a conductive polymer such as polyaniline or polythiophene dispersed in water in the form of fine particles. The water dispersion liquid has a low liquid viscosity, easy thin film coating, and excellent coating layer uniformity. The size of the fine particles is preferably 1 µm or less in terms of uniformity of the antistatic layer.

Moreover, it is preferable that the water-soluble conductive polymers or water-dispersible conductive polymers, such as said polyaniline and polythiophene, have a hydrophilic functional group in a molecule | numerator. Examples of the hydrophilic functional group include sulfone groups, amino groups, amide groups, imino groups, quaternary ammonium base groups, hydroxyl groups, mercapto groups, hydrazino groups, carboxyl groups, sulfate ester groups, phosphate ester groups, and salts thereof. Can be mentioned. By having a hydrophilic functional group in a molecule | numerator, it becomes easy to melt | dissolve in water or to disperse | distribute to water in particulate form, and the said water-soluble conductive polymer or water-dispersible conductive polymer can be prepared easily.

As an example of a water-soluble conductive polymer commercial item, polyaniline sulfonic acid (weight average molecular weight 150000 by Mitsubishi Rayon company make, polystyrene conversion), etc. are mentioned. Examples of commercially available water-dispersible conductive polymers include polythiophene-based conductive polymers (manufactured by Nagase Chemtech Co., Ltd., trade name, Denatron series).

As the material for forming the antistatic layer, a binder component is used together with the above antistatic agent for the purpose of film formation of the antistatic agent, improvement of adhesion to the optical film, and the like. Since the antistatic agent is a water-soluble conductive polymer or a water-dispersible conductive polymer, it is preferable to use a water-soluble or water-dispersible binder component. Examples of the binder component include polyurethane resin, polyester resin, acrylic resin, polyether resin, cellulose resin, polyvinyl alcohol resin, epoxy resin, polyvinylpyrrolidone, polystyrene resin, polyethylene glycol, pentaerythritol Etc. can be mentioned. In particular, a polyurethane resin, a polyester resin, and an acrylic resin are preferable. These binder components can use 1 type (s) or 2 or more types suitably according to the use. Although the usage-amount of a binder component also changes with kinds of antistatic agent, it is preferable that a water-soluble conductive polymer or a water-dispersible conductive polymer is 0.1-100 weight part with respect to 100 weight part of binder components, and also 1-50 weight part normally.

It is preferable that the surface resistivity of the said antistatic layer is 1x10 <^12> Pa / square or less, Furthermore, it is 1x10 <^11> Pa / square or less. When the surface resistivity exceeds 1 × 10 ¹² mA / □, the antistatic function is not sufficient, and static electricity is generated and charged by peeling of the surface protection film or friction of the optical film, and thus, the breakdown of the liquid crystal cell circuit and the Orientation defects may be caused.

The pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 3 of the antistatic pressure-sensitive adhesive optical film of the present invention is not particularly limited, and for example, acrylic polymer, silicone polymer, polyester, polyurethane, polyamide, polyether, fluorine or What uses a polymer, such as a rubber type, as a base polymer can be selected suitably, and can be used. In particular, those which are excellent in optical transparency, exhibit moderate wettability, cohesiveness and adhesive adhesion properties, and are excellent in weather resistance, heat resistance, and the like are preferably used. As showing such a characteristic, an acrylic adhesive is used preferably.

The acrylic pressure sensitive adhesive has an acrylic polymer having a monomer unit of alkyl (meth) acrylate as a main skeleton as a base polymer. In addition, (meth) acrylate refers to acrylate and / or methacrylate, and has the same meaning as (meth) of the present invention. The average carbon number of the alkyl group of the alkyl (meth) acrylate which comprises the main frame of an acryl-type polymer is about 1-12, and methyl (meth) acrylate and ethyl (meth) acryl are specific examples of an alkyl (meth) acrylate. Elate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, etc. can be illustrated, These can be used individually or in combination. Among these, alkyl (meth) acrylates having 1 to 9 carbon atoms of the alkyl group are preferable.

In the said acryl-type polymer, one or more types of various monomers are introduce | transduced by copolymerization in order to improve adhesiveness and heat resistance. As a specific example of such a copolymerization monomer, (meth) acrylic acid 2-hydroxyethyl, (meth) acrylic acid 2-hydroxypropyl, (meth) acrylic acid 4-hydroxybutyl, (meth) acrylic acid 6-hydroxy Hydroxy, such as hexyl, 8-hydroxyoctyl (meth) acrylic acid, 10-hydroxydecyl (meth) acrylic acid, 12-hydroxylauryl (meth) acrylic acid, or (4-hydroxymethylcyclohexyl) -methylacrylate Actual group-containing monomers; Carboxyl group-containing monomers such as (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid and crotonic acid; Acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; Caprolactone adducts of acrylic acid; Styrene sulfonic acid or allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamide propanesulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalenesulfonic acid Sulfonic acid group-containing monomers such as these; Phosphoric acid group containing monomers, such as 2-hydroxyethyl acryloyl phosphate, etc. are mentioned.

Furthermore, (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylol propane (meth) acrylamide, etc. (N-substituted) amide monomers; Alkyl (meth) acrylate alkylaminoalkyl monomers such as aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate and t-butylaminoethyl (meth) acrylate; Alkoxy (meth) acrylate alkyl monomers, such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; N- (meth) acryloyloxymethylene succinimide, N- (meth) acryloyl-6-oxyhexamethylene succinimide, N- (meth) acryloyl-8-oxyoctamethylene succinimide, N Succinimide type monomers, such as acryloyl morpholine, etc. are mentioned as a monomer example for the purpose of modification.

And vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole Vinyl monomers such as vinyl morpholine, N-vinylcarboxylic acid amides, styrene, α-methylstyrene, and N-vinyl caprolactam; Cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; Epoxy group-containing acrylic monomers such as glycidyl (meth) acrylate; Glycol-based acrylic ester monomers such as polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, methoxyethylene glycol (meth) acrylate, and methoxypolypropylene glycol (meth) acrylate; Acrylic ester ester monomers, such as (meth) acrylic acid tetrahydrofurfuryl, fluorine (meth) acrylate, silicone (meth) acrylate, and 2-methoxyethyl acrylate, can also be used.

Among these, carboxyl group-containing monomers, such as acrylic acid, are used suitably as an optical film use from a viewpoint of adhesiveness with respect to a liquid crystal cell, and adhesive durability.

Although the ratio of the said copolymerization monomer in an acrylic polymer is not specifically limited, It is preferable that it is about 0.1 to 10% by weight ratio.

The average molecular weight of the acrylic polymer is not particularly limited, but the weight average molecular weight is preferably about 300,000 to 2.5 million. The acrylic polymer can be produced by various known methods, and for example, a radical polymerization method such as a bulk polymerization method, a solution polymerization method or a suspension polymerization method can be appropriately selected. As a radical polymerization initiator, various well-known thing of azo type and a peroxide type can be used. Reaction temperature is about 50-80 degreeC normally, and reaction time is 1 to 8 hours. Moreover, the solution polymerization method is preferable among the said manufacturing methods, and ethyl acetate, toluene, etc. are generally used as a solvent of an acryl-type polymer. The solution concentration is usually about 20 to 80% by weight.

Examples of the base polymer of the rubber-based adhesive agent include natural rubber, isoprene-based rubber, styrene-butadiene-based rubber, recycled rubber, polyisobutylene-based rubber, and styrene-isoprene-styrene-based rubber, styrene-butadiene-styrene-based rubber, and the like. Can be mentioned. Examples of the base polymer of the silicone pressure sensitive adhesive include dimethyl polysiloxane, diphenyl polysiloxane, and the like, and those having a functional group such as a carboxyl group introduced therein can also be used.

Moreover, it is preferable to set it as the adhesive composition containing a crosslinking agent. As a polyfunctional compound which can be mix | blended with an adhesive, an organic type crosslinking agent and a polyfunctional metal chelate are mentioned. As an organic type crosslinking agent, an epoxy type crosslinking agent, an isocyanate type crosslinking agent, an imine type crosslinking agent, etc. are mentioned. As an organic type crosslinking agent, an isocyanate type crosslinking agent is preferable. Polyfunctional metal chelates are those in which a polyvalent metal is covalently or coordinated with an organic compound. Examples of the polyvalent metal atoms include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, Ti, and the like. have. Examples of the atoms in the organic compound covalently or coordinating include oxygen atoms, and examples of the organic compound include alkyl esters, alcohol compounds, carboxylic acid compounds, ether compounds, ketone compounds, and the like.

Although the compounding ratio of a base polymer, such as an acrylic polymer, and a crosslinking agent is not specifically limited, Usually, about 0.01-10 weight part of crosslinking agents (solid content) is preferable with respect to 100 weight part of base polymers (solid content), and about 0.1-5 weight part is furthermore desirable.

In addition, the pressure-sensitive adhesive, if necessary, fillers, plasticizers, glass fibers, glass beads, metal powder, other inorganic powders, fillers, pigments, colorants, fillers, antioxidants, ultraviolet absorbers, silane coupling agents and the like, Various additives can also be used suitably in the range which does not deviate from the objective of this invention. Moreover, it is good also as an adhesive layer etc. which contain microparticles | fine-particles and show light diffusivity.

As the optical film 1 used for the antistatic adhesive optical film of the present invention, one used for forming an image display device such as a liquid crystal display device is used, and the type thereof is not particularly limited. For example, a polarizing plate is mentioned as an optical film. The polarizing plate is generally used to have a transparent protective film on one side or both sides of the polarizer.

A polarizer is not specifically limited, Various things can be used. As a polarizer, a dichroic substance of iodine or a dichroic dye is adsorbed on a hydrophilic polymer film such as a polyvinyl alcohol-based film, a partially formalized polyvinyl alcohol-based film, or an ethylene-vinyl acetate copolymer-based partially saponified film. And polyene-based oriented films such as axially stretched, dehydrated polyvinyl alcohol and dehydrochloric acid polyvinyl chloride. Among these, the polarizer which consists of dichroic substances, such as a polyvinyl alcohol-type film and iodine, is preferable. Although the thickness in particular of these polarizers is not restrict | limited, Usually, it is about 5-80 micrometers.

The polarizer which uniaxially stretched the polyvinyl alcohol-type film by iodine, for example, can be produced by dyeing polyvinyl alcohol by dipping in an aqueous solution of iodine and stretching it 3 to 7 times its original length. As needed, it can also be immersed in aqueous solution, such as potassium iodide which may contain boric acid, zinc sulfate, zinc chloride, etc. If necessary, the polyvinyl alcohol-based film may be immersed in water and washed with water before dyeing. By washing the polyvinyl alcohol-based film with water, it is possible to clean the surface of the polyvinyl alcohol-based film by the anti-blocking agent or the blocking agent. In addition, the polyvinyl alcohol-based film is swelled to prevent nonuniformity such as staining. Stretching may be performed after dyeing with iodine, or may be performed while dyeing, or may be dyed with iodine after stretching. It can also extend | stretch in aqueous solution, such as boric acid and potassium iodide, or a water bath.

As a material for forming the transparent protective film formed on one side or both sides of the polarizer, it is preferable to have excellent transparency, mechanical strength, thermal stability, moisture barrier property, isotropy and the like. For example, polyester polymers, such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymers, such as diacetyl cellulose and triacetyl cellulose, acrylic polymers, such as polymethyl methacrylate, a polystyrene, an acrylonitrile styrene copolymer Styrene-type polymers, such as (AS resin), a polycarbonate polymer, etc. are mentioned. Also, polyethylene, polypropylene, polyolefin having a cyclo or norbornene structure, polyolefin polymer such as ethylene / propylene copolymer, vinyl chloride polymer, amide polymer such as nylon or aromatic polyamide, imide polymer, Phone polymer, polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, allylate polymer, polyoxymethylene polymer, Epoxy-based polymers or blends of the polymers may also be mentioned as examples of the polymer forming the transparent protective film. The transparent protective film may be formed as a cured layer of thermosetting or ultraviolet curable resins such as acrylic, urethane, acrylic urethane, epoxy, and silicone.

Further, the polymer film described in Japanese Unexamined Patent Publication No. 2001-343529 (WO01 / 37007), for example, a thermoplastic resin having a substituted and / or unsubstituted imide group in the (A) side chain, and (B) a substituted and / or Or the resin composition containing the thermoplastic resin which has unsubstituted phenyl and a nitrile group is mentioned. As a specific example, the film of the resin composition containing the alternating copolymer which consists of isobutylene and N-methyl maleimide, and an acrylonitrile styrene copolymer is mentioned. As a film, the film which consists of a mixed extrusion product of a resin composition, etc. can be used.

Although the thickness of a protective film can be suitably determined, it is generally 1-500 micrometers from a viewpoint of workability, thin-film property, etc., such as strength and handleability. 5-200 micrometers is especially preferable.

As a protective film, cellulose polymers, such as a triacetyl cellulose, are preferable from a viewpoint of polarization characteristic, durability, etc. In particular, a triacetyl cellulose film is preferable. In addition, when forming protective films on both sides of a polarizer, the protective film which consists of the same polymer material inside the surface may be used, and the protective film which consists of different polymer materials, etc. may be used. The polarizer and the protective film are usually in close contact with an aqueous adhesive or the like. As an aqueous adhesive agent, an isocyanate adhesive, a polyvinyl alcohol adhesive, a gelatin adhesive, a vinyl latex type, an aqueous polyurethane, an aqueous polyester, etc. can be illustrated.

The surface which does not adhere | attach the polarizer of the said transparent protective film may be the thing which carried out the process for the purpose of a hard-coat layer, an anti-reflective process, anti sticking, or diffused to anti glare.

Hard coat treatment is carried out for the purpose of preventing damage to the surface of the polarizing plate, for example, a method of adding a cured coating having excellent hardness and sliding characteristics, such as an acrylic or silicone type, to the surface of the transparent protective film. Or the like. The antireflection treatment is made for the purpose of preventing reflection of external light on the surface of the polarizing plate, and can be achieved by forming an antireflection film or the like according to the prior art. In addition, the sticking prevention treatment is performed for the purpose of preventing the adhesion with the adjacent layer of the other member.

In addition, antiglare treatment is carried out for the purpose of preventing external light from being reflected from the surface of the polarizing plate and impairing the visibility of the polarizing plate transmitted light. For example, sandblasting or embossing method of roughening method or transparent fine particles It can form by giving a fine uneven structure to the surface of a transparent protective film by a suitable method, such as a compounding method. Examples of the fine particles to be included in the formation of the surface fine concavo-convex structure include a conductive material composed of silica, alumina, titania, zirconia, tin oxide, indium oxide, cadmium oxide, antimony oxide, or the like having an average particle diameter of 0.5 to 50 µm. Transparent fine particles such as organic fine particles (including beads) composed of inorganic fine particles, crosslinked or uncrosslinked polymers, and the like are used. When forming a surface fine uneven structure, the use amount of microparticles | fine-particles is about 2-50 weight part generally with respect to 100 weight part of transparent resin which forms a surface fine uneven structure, and 5-25 weight part is preferable. The antiglare layer may also serve as a diffusion layer (visual magnification function, etc.) for diffusing the polarized plate transmitted light to enlarge the time and the like.

In addition, the anti-reflection layer, the anti-sticking layer, the diffusion layer or the antiglare layer may be formed on the transparent protective film itself, or may be formed as a separate optical layer from the transparent protective film.

As the optical film, for example, a liquid crystal display such as a reflection plate, a semi-transmissive plate, a retardation plate (including a wave plate such as a 1/2 wave plate or a quarter wave plate), a visual compensation film, a brightness enhancement film, and the like. The thing used as the optical layer which may be used for formation of an apparatus etc. is mentioned. These can be used alone or as an optical film, and can be laminated on the polarizing plate practically and can be used in one or two or more layers.

Particularly, a reflective polarizer or semi-transmissive polarizer in which a reflective plate or a semi-transmissive reflector is further laminated on the polarizing plate, an elliptically polarizing plate or circular polarizer in which a retardation plate is further laminated on the polarizing plate, and a light in which a visual compensation film is further laminated on the polarizing plate The viewing angle polarizing plate or the polarizing plate in which a brightness enhancement film is further laminated | stacked on a polarizing plate is preferable.

The reflective polarizer is formed by forming a reflective layer on the polarizer and is used to form a liquid crystal display device of a type that reflects and displays incident light emitted from the viewing side (display side). It is advantageous in that the display device can be made thinner. The reflective polarizing plate can be formed by a suitable method such as a method of laying a reflective layer made of metal or the like on one surface of the polarizing plate with a transparent protective layer interposed therebetween as necessary.

As a specific example of a reflection type polarizing plate, the thing which formed the reflection layer by laying the foil and vapor deposition film which consist of reflective metals, such as aluminum, on one surface of the transparent protective film which carried out the mat process as needed. Moreover, the fine particle is contained in the said transparent protective film, and it is set as the surface fine concavo-convex structure, and the thing which has a reflective layer of a fine concavo-convex structure on it, etc. are mentioned. The reflective layer of the fine concave-convex structure has the advantage of preventing the unevenness of light and dark by diffusing the incident light by diffuse reflection to prevent the directivity and the appearance of glare. In addition, the protective film containing fine particles also has the advantage that the incident light and its reflected light is diffused when passing through it to further suppress the contrast of the contrast. Formation of the fine concave-convex structure reflective layer reflecting the surface micro-concave-convex structure of the transparent protective film, for example, a metal directly on the surface of the transparent protective layer in a suitable manner such as vacuum deposition, ion plating, sputtering or plating method It can form by the method of laying.

The reflecting plate can also be used as a reflecting sheet formed by forming a reflecting layer on a suitable film based on the transparent film instead of the method of directly installing the transparent protective film of the polarizing plate. In addition, since the reflective layer is usually made of a metal, the use form in which the reflective surface is coated with a transparent protective film, a polarizing plate, or the like prevents the reduction of the reflectance due to oxidation, and furthermore, the viewpoint of long-term sustaining of the initial reflectance or the separation of the protective layer. It is preferable at the point of avoiding laying.

The semi-transmissive polarizing plate can be obtained by forming a semi-transmissive reflective layer such as a half mirror that reflects light through the reflective layer and transmits the above. The semi-transmissive polarizing plate is usually formed on the back of the liquid crystal cell, and when the liquid crystal display device or the like is used in a relatively bright atmosphere, the incident light is reflected from the viewing side (display side) to display an image. The liquid crystal display device of the type which displays an image etc. can be formed using the built-in power supply, such as a backlight built in the backside of this. That is, the transflective polarizing plate can save energy for use of a light source such as a backlight in a bright atmosphere, and is useful for forming a liquid crystal display device of the type that can be used using a built-in power supply even in a relatively dark atmosphere.

An elliptical polarizing plate or circular polarizing plate in which a retardation plate is further laminated on the polarizing plate will be described. A retardation plate or the like is used when changing linearly polarized light into elliptical polarization or circularly polarized light, or changing elliptical or circularly polarized light into linearly polarized light, or changing the polarization direction of linearly polarized light. In particular, a so-called quarter wave plate (also referred to as λ / 4 plate) is used as the phase difference plate which changes linearly polarized light into circularly polarized light or circularly polarized light into linearly polarized light. A half wave plate (also called a λ / 2 plate) is usually used when changing the polarization direction of linearly polarized light.

The elliptical polarizing plate compensates (prevents) coloring (blue or yellow) caused by birefringence of the super twisted nematic (STN) type liquid crystal display liquid crystal layer, and is effectively used for black-and-white display or the like without the coloring. In addition, controlling the three-dimensional refractive index is preferable because it can compensate (prevent) the coloration generated when the screen of the liquid crystal display device is viewed in the oblique direction. The circular polarizing plate is effectively used, for example, when adjusting the color tone of a reflection type liquid crystal display device in which an image becomes a color display, and also has an antireflection function.

As a retardation plate, the birefringent film formed by carrying out uniaxial or biaxial stretching process of a polymeric material, the orientation film of a liquid crystal polymer, the thing which supported the orientation layer of a liquid crystal polymer with the film, etc. are mentioned. Although the thickness of a retardation plate is not specifically limited, either, about 20-150 micrometers is common.

As a polymer material, for example, polyvinyl alcohol, polyvinyl butyral, polymethyl vinyl ether, polyhydroxyethyl acrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, polycarbonate, polyallylate, poly Sulfone, polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyphenylene sulfide, polyphenylene oxide, polyallyl sulfone, polyamide, polyimide, polyolefin, polyvinyl chloride, cellulose polymer, norbornene-based resin, or These binary and ternary various copolymers, graft copolymers, blends, etc. are mentioned. These high molecular materials become alignment materials (stretched films) by stretching or the like.

Examples of the liquid crystal polymer include various main chain or side chains in which the conjugated linear atomic group (mesogen) for imparting liquid crystal alignment is introduced into the main chain or side chain of the polymer. Specific examples of the main chain type liquid crystal polymer include, for example, nematic oriented polyester liquid crystal polymers, discotic polymers and cholesteric polymers having a structure in which mesogenic groups are bonded to the spacer portion providing flexibility. . Specific examples of the side chain type liquid crystal polymer include a polysiloxane, polyacrylate, polymethacrylate, or polymalonate as a main chain skeleton, and a nematic orientation impartable parasubstituted ring having a spacer portion composed of a conjugated atomic group as a side chain. The thing which has the mesogenic part which consists of a type compound unit, etc. are mentioned. These liquid crystal polymers, for example, by rubbing the surface of a thin film such as polyimide or polyvinyl alcohol formed on a glass plate, a solution of the liquid crystalline polymer on an alignment treatment surface such as a gradient deposition of silicon oxide It develops by heat-processing.

The retardation plate may have a suitable retardation according to the purpose of use, for example, for the purpose of compensating coloring or vision due to birefringence of various wavelength plates and liquid crystal layers, or by laminating two or more kinds of retardation plates. The thing which controlled optical characteristics, such as these, may be sufficient.

The elliptical polarizing plate and the reflective elliptic polarizing plate are obtained by laminating a polarizing plate or a reflective polarizing plate and a phase difference plate in a suitable combination. Such elliptical polarizing plates and the like can be formed by separately stacking them in order in the manufacturing process of the liquid crystal display device so as to be a combination of the (reflective) polarizing plates and the retardation plates. In addition, the stability of the quality and the lamination workability is excellent, there is an advantage that can improve the manufacturing efficiency of the liquid crystal display device.

The visual compensation film is a film for widening the viewing angle so that an image can be seen relatively clearly even when the screen of the liquid crystal display device is viewed from a slightly inclined direction rather than perpendicular to the screen. Such a visually compensated retardation plate consists of, for example, supporting an alignment layer such as a liquid crystal polymer on an alignment film such as a retardation plate or a liquid crystal polymer or a transparent substrate. A conventional retardation plate is a polymer film having birefringence uniaxially stretched in the plane direction thereof, whereas a retardation plate used as a visual compensation film is a polymer film or birefringence stretched biaxially in the plane direction in the retardation plate used as a visual compensation film. A bidirectional stretched film such as a birefringent polymer or a diagonally oriented film is used, which is uniaxially stretched and has a refractive index in the thickness direction that is also stretched in the thickness direction. Examples of the inclined alignment film include those in which the polymer film is stretched and / or shrunk under the action of the shrinkage force by heating by adhering a heat shrink film to the polymer film, or the inclined orientation of the liquid crystal polymer. have. As the raw material polymer of the retardation plate, the same polymer as that described in the retardation plate is used, and suitable ones for the purpose of preventing the coloring due to the change of the viewing angle based on the phase difference by the liquid crystal cell, and expanding the viewing angle of the good visibility can be used. have.

In addition, in order to achieve a wide viewing angle of good visibility, an optical compensation retardation plate having a triacetyl cellulose film supported by an optically anisotropic layer composed of an alignment layer of a liquid crystal polymer, particularly an inclined alignment layer of a discotic liquid crystal polymer, can be preferably used. have.

A polarizing plate having a polarizing plate and a brightness enhancing film is usually formed on the rear side of the liquid crystal cell and used. The luminance enhancing film reflects linearly polarized light on a predetermined polarization axis or circularly polarized light in a predetermined direction when natural light is incident due to a backlight or a reflection from the back of a liquid crystal display device, and transmits other light. The laminated polarizing plate is made to receive light from a light source such as a backlight to obtain transmitted light in a predetermined polarization state, and light other than the predetermined polarization state is reflected without being transmitted. The light reflected from the luminance-enhancing film surface is inverted again through a reflecting layer or the like formed on the rear side thereof, and re-injected into the luminance-enhancing film, and the light transmitted through the luminance-enhancing film is transmitted through part or all of the light as a light of a predetermined polarization state. It is possible to improve the brightness by increasing the amount of light that can be used for liquid crystal display and image display by supplying polarized light which is hardly absorbed by the polarizer. That is, when light is incident on the back of the liquid crystal cell with a backlight or the like without using the brightness enhancement film, light having a polarization direction that does not coincide with the polarization axis of the polarizer is almost absorbed by the polarizer and does not transmit the polarizer. Do not. That is, although it depends also on the characteristic of the polarizer used, about 50% of light is absorbed by a polarizer, and the quantity of light which can be used for a liquid crystal image display etc. decreases by that amount, and an image becomes dark. The luminance enhancing film reflects one roll of light having a polarization direction absorbed by the polarizer into the luminance enhancing film without being incident on the polarizer, and is then inverted through the reflective layer formed on the rear side thereof and then reincident to the luminance enhancing film. Repeat. Since only the polarized light in which the polarization direction of the light reflected and inverted between the two becomes the polarization direction through which the polarizer passes, the luminance-enhancing film is transmitted to the polarizer, so that light such as a backlight can be efficiently displayed on the image of the liquid crystal display device. It can be used to brighten the screen.

A diffusion plate may be formed between the luminance enhancing film and the reflective layer. The light in the polarization state reflected by the brightness enhancement film is directed toward the reflecting layer or the like, but the diffuser plate provided uniformly diffuses the light passing therethrough and simultaneously resolves the polarization state to become a non-polarization state. That is, the light in the natural light state is reflected through the reflecting layer or the like toward the reflecting layer or the like, and passes through the diffuser plate again and is reincident to the luminance enhancing film. As such, by forming a diffuser plate between the luminance enhancing film and the reflective layer to return the polarized light to the original natural light, the brightness of the display screen can be maintained, while at the same time, the brightness of the display screen can be reduced to provide a uniform and bright screen. have. By forming such a diffuser plate, it is considered that the number of times of repeated reflection of the first incident light can be moderately increased to provide a uniform and bright display screen with the diffusion function of the diffuser plate.

The luminance-enhancing film is, for example, a cholesteric liquid crystal polymer that exhibits the property of transmitting linearly polarized light of a predetermined polarization axis and reflecting other light, such as a multilayer film of a dielectric film or a multilayer stack of a thin film film having different refractive index anisotropy. As in the case where the oriented film or the oriented liquid crystal layer is supported on the film base material, any suitable one can be used, such as exhibiting a property of reflecting any circularly polarized light in a left rotation or a right rotation and transmitting other light.

Therefore, in the luminance improvement film of the type which transmits the linearly polarized light of the said predetermined polarization axis, it can transmit efficiently, restraining the absorption loss by a polarizing plate by making the transmitted light into a polarizing plate as it enters. On the other hand, in a luminance enhancement film of a type that transmits circularly polarized light, such as a cholesteric liquid crystal layer, the polarized light may be incident on a polarizer as it is. To be incident on the polarizing plate. In addition, circular polarization can be converted into linearly polarized light by using a quarter wave plate as the retardation plate.

A retardation plate which functions as a quarter wave plate at a wide wavelength such as visible range is, for example, a phase difference layer exhibiting retardation characteristics different from that of a retardation plate functioning as a quarter wave plate with respect to pale color light having a wavelength of 550 nm. For example, it can obtain by the method of superimposing the retardation layer which functions as a 1/2 wave plate. Therefore, the retardation plate disposed between the polarizing plate and the brightness enhancement film may be made of one or two or more retardation layers.

In addition, also in the cholesteric liquid crystal layer, by combining the two or three or more layers with a combination of different reflection wavelengths, reflecting circularly polarized light in a wide wavelength range such as visible light can be obtained. The transmission circular polarization of a wide wavelength range can be obtained.

Moreover, the polarizing plate may consist of what laminated | stacked the polarizing plate and two or three or more optical layers like the said polarization split type polarizing plate. Therefore, the reflective elliptical polarizing plate, the semi-transmissive elliptical polarizing plate, etc. which combined the said reflective polarizing plate, the transflective polarizing plate, and the retardation plate may be sufficient.

The optical film in which the optical layer is laminated on the polarizing plate may be formed by laminating the optical films separately in order in the manufacturing process of the liquid crystal display device. It is excellent in that it is possible to improve the manufacturing process of the liquid crystal display device and the like. Suitable lamination means such as an adhesive layer can be used for lamination. At the time of adhering the polarizing plate and the other optical layer, these optical axes can be made at an appropriate placement angle according to the desired phase difference characteristics and the like.

Next, a method for preparing an antistatic optical film and an antistatic adhesive optical film will be described.

The antistatic layer 2 is formed with the coating liquid containing the conductive polymer and binder component which are water-soluble or water dispersible with respect to the above-mentioned optical film 1. It is preferable to adjust the solid content concentration of coating liquid to about 0.5 to 5 weight%. The coating solution is applied and dried using a coating method such as a roll coating method such as reverse coating or gravure coating, a spin coating method, a screen coating method, a fountain coating method, a dipping method, a spray method, and the like to form an antistatic layer.

It is preferable that the thickness of an antistatic layer is 5-1000 nm. The thickness of the antistatic layer is usually 5000 nm or less from the viewpoint of deterioration of the optical characteristics. However, when the thickness of the antistatic layer becomes thick, breakage is likely to occur in the antistatic layer due to lack of strength of the antistatic layer, and sufficient adhesion may not be obtained. The thickness of the antistatic agent is preferably 500 nm or less, 300 nm or less, and 200 nm or less. It is preferable to set it as 5 nm or more and 10 nm or more from ensuring adhesiveness and suppressing peeling charge. On the other hand, the peeling charging effect is preferably a thick antistatic layer, but is less than or equal to 200 nm or more. From this point, it is preferable that they are 5-500 nm, 10-300 nm, and 10-200 nm.

When forming the antistatic layer 2, the optical film 1 can be activated. Various methods can be employ | adopted for an activation process, For example, a corona treatment, a low pressure UV treatment, a plasma treatment, etc. can be employ | adopted. The activation treatment is effective when using an aqueous solution containing a water-soluble conductive polymer as an antistatic agent, and can suppress splashing when applying the aqueous solution. The activation treatment is effective when the optical film 1 is particularly a polyolefin resin or a norbornene resin.

Formation of the adhesive layer 3 is performed by laminating on the said anchor layer 4. It does not restrict | limit especially as a formation method, The method of apply | coating an adhesive solution to an anchor layer, and drying it, the method of transferring by the release sheet which formed the adhesive layer, etc. are mentioned. Although the thickness of an adhesive layer is not specifically limited, It is preferable to set it as about 10-40 micrometers.

Examples of the constituent material of the release sheet include suitable resins such as synthetic resin films such as paper, polyethylene, polypropylene, and polyethylene terephthalate, rubber sheets, paper, cloth, nonwoven fabrics, nets, foam sheets, metal foils, and laminates. Can be. In order to improve the peelability in the adhesive layer 3, the surface of a release sheet may be given low adhesive peeling processes, such as a silicone treatment, a long chain alkyl treatment, and a fluorine treatment.

Moreover, in each layer, such as an optical film and an adhesive layer of an antistatic adhesive optical film of this invention, a salicylic acid ester type compound, a benzophenol type compound, a benzotriazole type compound, a cyanoacrylate type compound, nickel, for example The ultraviolet absorbing power may be imparted by a method such as a treatment with an ultraviolet absorber such as a complex salt compound.

The antistatic adhesive optical film of the present invention can be suitably used for forming various image display devices such as liquid crystal display devices. Formation of a liquid crystal display device can be performed according to the prior art. That is, a liquid crystal display device is generally formed by appropriately assembling a component such as a liquid crystal cell, an antistatic adhesive optical film, and an illumination system, if necessary, and mounting a driving circuit. There is no restriction | limiting in particular except using an optical film, According to the conventional method. Also about a liquid crystal cell, what is arbitrary types, such as a TN type, STN type, (pi) type, can be used, for example.

An appropriate liquid crystal display device, such as a liquid crystal display device in which an antistatic adhesive optical film is disposed on one side or both sides of a liquid crystal cell, or a backlight or reflector used in an illumination system, can be formed. In that case, the optical film according to the present invention can be provided on one side or both sides of the liquid crystal cell. When forming optical films on both sides, they may be the same or different. In the formation of the liquid crystal display device, for example, a diffuser plate, an antiglare layer, an antireflection film, a protective plate, a prism array, a lens array sheet, a light diffuser plate, a backlight, or the like, at a suitable position, one layer or two layers or more. Can be placed.

Next, the organic electroluminescent device (organic EL display device) will be described. The optical film (polarizing plate etc.) of this invention can be applied also to an organic electroluminescence display. In general, an organic EL display device forms a light emitting body (organic electroluminescent light emitting body) by sequentially stacking a transparent electrode, an organic light emitting layer, and a metal electrode on a transparent substrate. Here, the organic light emitting layer is a laminate of various organic thin films, for example, a laminate of a hole injection layer made of a triphenylamine derivative or the like and a light emitting layer made of a fluorescent organic solid such as anthracene, or such a light emitting layer and phenylene Background Art A structure having various combinations such as a laminate of an electron injection layer made of a derivative and the like and a laminate of these hole injection layers, a light emitting layer and an electron injection layer is known.

In the organic EL display device, holes and electrons are injected into the organic light emitting layer by applying a voltage to the transparent electrode and the metal electrode, and energy generated by the recombination of these holes and electrons excites the fluorescent material, and the excited fluorescent material is based on It emits light on the principle of emitting light when returning to the state. The recombination mechanism is similar to that of a general diode, and as can be expected, the current and the luminous intensity exhibit strong nonlinearity accompanied by rectification with respect to the applied voltage.

In the organic EL display device, at least one electrode must be transparent in order to extract light emitted from the organic light emitting layer, and a transparent electrode formed of a transparent conductor such as indium tin oxide (ITO) is usually used as an anode. On the other hand, in order to easily inject electrons and increase luminous efficiency, it is important to use a material having a small work function for the cathode, and metal electrodes such as Mg-Ag and Al-Li are usually used.

In the organic EL display device having such a configuration, the organic light emitting layer is formed of a very thin film having a thickness of about 10 nm. For this reason, the organic light emitting layer also transmits light almost completely like the transparent electrode. As a result, the light incident on the surface of the transparent substrate during non-emission and transmitted through the transparent electrode and the organic light emitting layer and reflected by the metal electrode again goes to the surface side of the transparent substrate, so that the display of the organic EL display device when viewed from the outside The surface looks like a mirror.

An organic EL display device comprising an organic electroluminescent emitter comprising a transparent electrode on the front side of an organic light emitting layer that emits light by application of a voltage and a metal electrode on the back side of the organic light emitting layer. It is possible to form a polarizing plate on the surface side of the substrate and simultaneously form a retardation plate between these transparent electrodes and the polarizing plate.

Since the retardation plate and the polarizing plate have a function of polarizing light incident from the outside and reflected by the metal electrode, the retardation plate and the polarizing plate do not visually recognize the mirror surface of the metal electrode from the outside. In particular, when the phase difference plate is constituted by a quarter wave plate and the angle between the polarization direction of the polarizing plate and the phase difference plate is adjusted to π / 4, the mirror surface of the metal electrode can be completely shielded.

That is, only the linearly polarized light component transmits external light incident on the organic EL display device by the polarizing plate. This linearly polarized light is generally elliptically polarized by the retardation plate. In particular, the linearly polarized light becomes circularly polarized light when the retardation plate is a quarter wave plate and the angle between the polarizing plate and the retardation plate is? / 4.

The circularly polarized light is transmitted through the transparent substrate, the transparent electrode, and the organic thin film to be reflected by the metal electrode, and then is transmitted through the organic thin film, the transparent electrode, and the transparent substrate, and then linearly polarized back to the retardation plate. And since this linearly polarized light is orthogonal to the polarization direction of a polarizing plate, it cannot transmit a polarizing plate. As a result, the mirror surface of the metal electrode can be completely shielded.

(Example)

Although an Example demonstrates this invention concretely below, this invention is not limited by these Examples. In addition, in each example, both part and% are basis of weight.

Example 1

(Production of optical film)

A polyvinyl alcohol film having a thickness of 80 μm was stretched five times in an aqueous solution of iodine at 40 ° C., and then dried at 50 ° C. for 4 minutes to obtain a polarizer. The triacetyl cellulose film was adhere | attached on both sides of this polarizer using the polyvinyl alcohol-type adhesive agent, and the polarizing plate was obtained.

(Formation of antistatic layer)

The aqueous solution of 0.8% of solid content concentration was prepared using the polyurethane-type resin as a binder and water-soluble polythiophene type conductive polymer. In addition, the ratio (weight ratio) of a binder and a conductive polymer is former: latter = 10: 1. The solution was applied to one surface of the polarizing plate after drying to have a thickness of 100 nm, and dried at 80 ° C. for 2 minutes to form an antistatic layer.

(Formation of Adhesive Layer)

As a base polymer, 95 parts of butyl acrylate, 5 parts of acrylic acid, and 0.2 parts of benzoyl peroxide are dissolved in 300 parts of ethyl acetate and reacted at about 60 DEG C for 6 hours under stirring to contain a weight average molecular weight of 2 million acrylic polymers (solid content 20% ) Was used. 0.5 parts of Coronate L manufactured by Nippon Polyurethane Co., Ltd. which is an isocyanate polyfunctional compound was added to the acrylic polymer solution with respect to 100 parts of polymer solids. After apply | coating this adhesive solution by the reverse roll coating method on a release film (polyethylene terephthalate base material: diafoil MRF38, the Mitsubishi Chemical polyester make) so that thickness may become 25 micrometers after drying, a release film is again provided on it. And dried in a hot air circulation oven to form a pressure-sensitive adhesive layer.

(Preparation of antistatic adhesive optical film)

An antistatic layer formed with an adhesive layer was attached to an antistatic layer formed on the surface of the antistatic polarizing plate to prepare an antistatic adhesive polarizing plate.

Example 2

In antistatic layer formation of Example 1, the antistatic adhesive polarizing plate was produced by the same method as Example 1 except having changed the polyurethane-type resin which is a binder into acrylic resin.

Example 3

In formation of the antistatic layer of Example 1, the antistatic adhesive polarizing plate was produced by the same method as Example 1 except having changed the polyurethane-type resin which is a binder into polyester-type resin.

Example 4

In Example 1, an antistatic adhesive polarizing plate was produced by the same method as in Example 1 except that the following optical film was used.

(Optical film)

Triacetylcellulose film surface of a film in which a triacetyl cellulose film having a thickness of 80 µm is attached to one side of a polarizer having a thickness of 20 µm and a discotic liquid crystal layer is formed on one side of the triacetyl cellulose film having a thickness of 80 µm on the other side. It was attached to prepare a polarizing plate containing an optical compensation layer. This discotic liquid crystal layer was made into the formation surface of the antistatic layer.

Example 5

In forming the antistatic layer of Example 1, an antistatic adhesive polarizing plate was prepared by the same method as in Example 1 except that the polyurethane-based resin as a binder was changed to an acrylic resin and the one produced in Example 4 as an optical film was used. Produced.

Example 6

In forming the antistatic layer of Example 1, the antistatic adhesive type was prepared by the same method as in Example 1, except that the polyurethane-based resin as a binder was replaced with a polyester-based resin and the one produced in Example 4 as an optical film was used. The polarizing plate was produced.

Comparative Example 1

In forming the antistatic layer of Example 1, an antistatic adhesive polarizing plate was produced by the same method as in Example 1 except that only a water-soluble polythiophene conductive polymer was used without using a polyurethane resin as a binder.

Comparative Example 2

In forming the antistatic layer of Example 1, only the water-soluble polythiophene conductive polymer was used without using the polyurethane-based resin as a binder, and the same method as in Example 1 was used except that the one produced in Example 4 was used as the optical film. Thereby, an antistatic adhesive polarizing plate was produced.

The following evaluation was performed about the antistatic adhesive optical film etc. which were obtained by the said Example and the comparative example. Table 1 shows the results of the evaluation.

(Adhesive removal)

The antistatic adhesive optical film produced above was punched into a 25 mm × 150 mm size with a Thompson blade type and the cut end was contacted with a smooth SUS plate 20 times. Then, the edge part of each antistatic adhesive optical film was visually confirmed, and the following references | standards evaluated. In addition, the area of adhesive dropping off is shown. The results are shown in Table 1.

: 점착제 탈락 없음

: No adhesive drop off

△: no dropping of the adhesive of 0.3 mm or more

X: There exist adhesive falloff of 0.3 mm or more

(Adhesive residue)

The produced antistatic adhesive optical film was cut into a size of 100 mm x 100 mm and attached to the liquid crystal panel. After leaving this panel for 48 hours under 40 degreeC x 92% of humidification conditions, the antistatic adhesive optical film was peeled off by hand from a liquid crystal panel, and the following references | standards evaluated.

: 점착제 잔류 없음

: No adhesive residue

X: The adhesive remains on the panel

(Adhesiveness)

The produced antistatic adhesive optical film was cut into 25 mm width x 50 mm length. The pressure-sensitive adhesive layer surface and the surface of the polyethylene terephthalate film having a thickness of 50 µm were attached so as to be in contact with the vapor deposition surface of the film in which indium-tin oxide was deposited. Then, after peeling off the edge part of a polyethylene terephthalate film by hand and confirming that an adhesive adheres to the polyethylene terephthalate film side, 180 degree peeling using a tensile tester (made by Shimadzu Corporation, Autograph AG-1), The adhesiveness (N / 25mm) of an antistatic layer and an adhesive layer was measured in room temperature atmosphere (25 degreeC) by the tensile velocity of 300 mm / min. It is preferable that such adhesiveness (N / 25mm) is 15N / 25mm or more.

(Antistatic effect)

The produced antistatic adhesive optical film was cut into a size of 100 mm x 100 mm and attached to the liquid crystal panel. The panel was placed on a backlight having a brightness of 10000 cd / m 2, and 5 kV of static electricity was generated using an electrostatic generator (ESD, ESD-8012A, manufactured by SANKI Co., Ltd.), causing liquid crystal alignment disturbance. The recovery time (seconds) of display defects due to this orientation defect was measured using an instantaneous multi-photometric detector (MCPD-3000, manufactured by Otsuka Electronics Co., Ltd.).

(Surface resistivity)

The surface resistivity (Ω / □) of the antistatic layer was measured at an applied voltage of 500V using a surface resistance measuring instrument (manufactured by Mitsubishi Chemical Corporation, Hiresta MCP-HT450).

(Exterior)

: 대전방지층의 표면에 얼룩이 없이 균일함

: Uniformity without stain on the surface of antistatic layer

X: The surface of the antistatic layer is stained and a problem occurs in display characteristics

Adhesive dropout Adhesive residue Adhesiveness (N / 25㎜) Bad display recovery time (seconds) Surface resistivity (Ω / □) Exterior Example 1

15 <1 3.0 × 10 ⁸

Example 2

15 <1 2.0 × 10 ⁸

Example 3

16 <1 2.0 × 10 ⁸

Example 4

15 <1 4.0 × 10 ⁸

Example 5

15 <1 5.0 × 10 ⁸

Example 6

16 <1 4.0 × 10 ⁸

Comparative Example 1 × × 9 <1 3.0 × 10 ⁹

Comparative Example 2 × × 9 <1 4.0 × 10 ⁹

1 is an example of sectional drawing of the antistatic adhesive optical film of this invention.

* Explanation of symbols for the main parts of the drawings *

1: Optical film

2: antistatic layer

3: adhesive layer

Claims (2)

Applying a coating liquid composed of a water-soluble or water-dispersible conductive polymer and a binder component to at least one surface of the optical film, and Drying the applied coating liquid to form an antistatic layer, the method for producing an antistatic optical film. Applying a coating liquid composed of a water-soluble or water-dispersible conductive polymer and a binder component to at least one surface of the optical film, Drying the applied coating liquid to form an antistatic layer, and Method of manufacturing an antistatic adhesive optical film comprising the step of forming an adhesive layer on the antistatic layer.

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