JP2005313027A - Conductive film and its manufacturing method, optical element and image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a conductive film capable of forming a conductive layer good in adhesion even under a heat-resistant/humidity-resistant environment. <P>SOLUTION: In manufacturing the conductive film by overlaying at least one side of a transparent base material film with the conductive layer, which is formed of a curable resin and a conductive inorganic filler, a solvent capable of dissolving the material of the transparent base material is applied to the transparent base material and, after the coated film is dried, the conductive layer is formed on the solvent treated surface of the transparent base material. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a conductive film. The conductive film is used for various optical film applications as a hard coat film having a hard coat layer and an antireflection film having an antireflection layer. Those applied to optical elements such as polarizing plates can be suitably used in various image display devices such as liquid crystal display devices, organic EL display devices, PDPs, and CRTs. For example, it is suitably used in displays such as word processors, computers, televisions, car navigation monitors, and video camera monitors. Further, in an optical system product such as sunglasses and goggles, it can be suitably used as a constituent member such as a polarizing filter or an antireflection filter or a member for sticking.

  Image display devices such as liquid crystal panels, organic EL display devices, and PDPs are establishing a firm position as displays through recent research and development. However, in the case of a car navigation monitor or a video camera monitor that is frequently used under bright illumination, the visibility is significantly reduced due to surface reflection. Therefore, most of these outdoor-use displays have antireflection treatment on the surface. The antireflection treatment is generally performed by using a dry method such as a vacuum deposition method, a sputtering method, a CVD method, or a plurality of thin films made of materials having different refractive indexes by a wet method using a die or a gravure roll coating. Designs are made to produce a multilayer laminate and reduce reflection in the visible light region as much as possible.

  For example, a high refractive index hard coat layer is laminated on a transparent substrate film, and a low refractive index layer is further formed thereon, thereby satisfying the requirement for antireflection by utilizing the cancellation effect due to the interference of light. An antireflection film has been proposed (see Patent Document 1).

  The antireflection film or the like is often used in the outermost layer as a constituent member or a sticking member in the above applications. When used in the outermost layer, static electricity is likely to be generated, and dust such as dust is likely to adhere due to the static electricity. Therefore, for the purpose of imparting antistatic properties to the antireflection film, a conductive layer is provided to prevent adverse effects due to static electricity. The conductive layer is usually formed by a coating liquid in which conductive ultrafine particles are dispersed and contained in a binder.

  As the material of the transparent base film used for the antireflection film, triacetyl cellulose (hereinafter abbreviated as TAC), polycarbonate, acrylic based on its low cost and excellent optical characteristics and reliability in each environment. Resin is frequently used. However, the adhesion between these transparent substrate films and the conductive layer was not sufficient. In particular, anti-reflection films are used in car navigation displays and the like that have been rapidly spreading in recent years. However, since the temperature and humidity in passenger cars are repeatedly changed greatly, they are transparent under heat and humidity resistance. Adhesion between the material film and the conductive layer is required. In addition, the transparent base film and the conductive layer have poor adhesion, and TAC has a high hygroscopic property and also has a high coefficient of thermal expansion, so that it has a drawback that it easily changes in dimensions due to a temperature change. For this reason, high stress is generated between the conductive layer, serious troubles such as peeling of the conductive layer occur, and there is a problem in adhesion in a heat and moisture resistant environment.

In order to improve the adhesion of the coating layer to a transparent substrate film such as TAC, it has been proposed to use methyl isobutyl ketone as a solvent for the coating solution for forming the coating layer (see Patent Document 2). However, Patent Document 2 relates to a roughened layer (hard coat layer) using an ultraviolet curable resin as a coating layer, and cannot sufficiently improve the adhesion to the conductive layer. Further, in Patent Document 2, since an ultraviolet curable resin is used, when the layer thickness is thin, there is a problem of causing curing failure due to oxygen inhibition. For a conductive layer having a general layer thickness of 0.5 μm or less, It was not applicable.
JP 2002-301783 A Japanese Patent Laid-Open No. 11-209717

  An object of this invention is to provide the manufacturing method of an electroconductive film which can form an electroconductive layer with favorable adhesiveness also in a heat-resistant / humid-proof environment.

  Another object of the present invention is to provide an optical element using the conductive film, and further to provide an image display device equipped with the optical element or the like.

  As a result of intensive studies to solve the above problems, the present inventors have found that the object can be achieved by the manufacturing method shown below, and have completed the present invention.

That is, the present invention provides a conductive film in which a conductive layer formed of a curable resin and a conductive inorganic filler is laminated on at least one surface of a transparent substrate film.
After applying a solvent capable of dissolving the material of the transparent substrate film to the transparent substrate film and drying,
The present invention relates to a method for producing a conductive film, comprising forming a conductive layer on a solvent-treated surface of a transparent substrate film.

  In the said invention, in order to improve the adhesiveness of a transparent base film and a conductive layer, after carrying out the surface treatment of the transparent base film with a solvent previously, the conductive layer is formed in the solvent processing surface of the said film. Since the solvent-treated surface of the transparent substrate film is dissolved and / or swelled by the solvent, the adhesion strength between the transparent substrate film and the conductive layer is greatly increased. Therefore, the adhesion can be satisfied even in a heat and humidity resistant environment.

  In the method for producing the conductive film, the solvent is preferably a ketone solvent. The ketone solvent is preferably cyclohexanone and / or cyclopentanone.

  The ketone solvent has a high dissolving power with respect to the transparent substrate film, and is suitable for surface treatment of the transparent substrate film before forming a conductive layer on the transparent substrate film. The ketone solvent has a normal boiling point of 155.7 ° C. and a relatively high temperature, and has an appropriate dissolving power. Therefore, cyclohexanone, which can achieve both a dissolving power and a penetrating power for a transparent base film, Cyclopentanone and the like are preferable.

  In the method for producing a conductive film, the conductive layer is formed by applying a coating liquid containing a curable resin, a conductive inorganic filler, and a solvent to the solvent-treated surface of the transparent base film, followed by drying and curing. It is preferable. As the curable resin, an inorganic thermosetting resin is suitable.

  When an inorganic thermosetting resin is used as the curable resin that is a binder for the conductive layer, a conductive layer having a high surface hardness can be formed. The inorganic thermosetting resin is also preferable in terms of improving the adhesion between the solvent-treated surface of the transparent base film and the conductive layer. Moreover, according to the inorganic thermosetting resin, the conductive layer can be formed without causing poor curing even when the thickness of the general conductive layer is 0.5 μm or less.

  In the method for producing the conductive film, the transparent substrate film is preferably a triacetyl cellulose film.

  As the transparent substrate film, it can be applied to various transparent substrate films such as triacetylcellulose-based, polycarbonate-based, and acrylic-based resins. However, the solubility in a solvent, particularly a ketone-based solvent, is preferable, and the conductive layer adheres. A triacetyl cellulose film is preferred because the strength can be increased.

  Moreover, this invention relates to the electroconductive film obtained by the said manufacturing method. The conductive film can be used as a hard coat film in which a hard coat layer is formed on a conductive layer. Moreover, the said electroconductive film can provide anti-glare property by making the hard-coat layer surface uneven | corrugated shape.

  The conductive film can be used as an antireflection film in which an antireflection layer is formed on a conductive layer (on a hard coat layer).

  The antireflection film or the like led from the conductive film of the present invention has sufficient reliability for in-vehicle use because of good adhesion between the conductive layer and the transparent substrate film. In particular, the antireflection film exhibits excellent reflection characteristics by preventing reflection of external light such as sunlight and fluorescent lamps on the display.

  The present invention also relates to an optical element characterized in that the conductive film is provided on one side or both sides of the optical element. Furthermore, this invention relates to the image display apparatus carrying the said electroconductive film or optical element.

  In this invention, after apply | coating the solvent which can melt | dissolve the said transparent base film to a transparent base film and making it dry, a conductive layer is formed in the solvent processing surface of a transparent base film. Hereinafter, preferred embodiments of the present invention will be described.

  As the transparent substrate film, a film excellent in transparency, mechanical strength, thermal stability, moisture shielding property, isotropy and the like is preferable. Examples thereof include films made of a transparent polymer such as a polyester polymer such as polyethylene terephthalate and polyethylene naphthalate, a cellulose polymer such as diacetyl cellulose and triacetyl cellulose, a polycarbonate polymer, and an acrylic polymer such as polymethyl methacrylate. Styrene polymers such as polystyrene and acrylonitrile / styrene copolymers, polyethylene, polypropylene, polyolefins having a cyclic or norbornene structure, olefin polymers such as ethylene / propylene copolymers, vinyl chloride polymers, nylon and aromatic polyamides, etc. Examples thereof include films made of transparent polymers such as amide polymers. Furthermore, imide polymers, sulfone polymers, polyether sulfone polymers, polyether ether ketone polymers, polyphenylene sulfide polymers, vinyl alcohol polymers, vinylidene chloride polymers, vinyl butyral polymers, arylate polymers, polyoxymethylene polymers Examples thereof include a film made of a transparent polymer such as a polymer, an epoxy-based polymer, and a blend of the aforementioned polymers.

  Moreover, the polymer film described in JP-A-2001-343529 (WO01 / 37007), for example, (A) a thermoplastic resin having a substituted and / or unsubstituted imide group in the side chain, and (B) a substitution in the side chain And / or a resin composition containing a thermoplastic resin having unsubstituted phenyl and a nitrile group. A specific example is a film of a resin composition containing an alternating copolymer composed of isobutylene and N-methylmaleimide and an acrylonitrile / styrene copolymer. As the film, a film made of a mixed extruded product of the resin composition or the like can be used. Since these films have a small phase difference and a small photoelastic coefficient, when applied to a protective film such as a polarizing plate, it is possible to eliminate defects such as unevenness due to distortion. Excellent.

  As the transparent substrate film, a cellulose polymer, a polycarbonate polymer, an acrylic polymer and the like are preferable. Among these, a cellulose-based polymer, particularly triacetyl cellulose is preferable. The surface of the transparent substrate film can be subjected to surface treatment such as saponification treatment, corona discharge treatment, sputtering treatment, low-pressure UV irradiation, plasma treatment, etc. A triacetyl cellulose film is preferred.

  The thickness of the transparent substrate film can be appropriately determined, but is generally about 10 to 300 μm from the viewpoints of workability such as strength and handleability, and thin layer properties. 20-300 micrometers is especially preferable, and 30-200 micrometers is more preferable.

  The solvent applied to the transparent base film and subjected to the surface treatment is not particularly limited as long as it is a solvent capable of dissolving the material of the transparent base film, and can be appropriately selected according to the transparent base film. Moreover, the solvent which can melt | dissolve a transparent base film may mix and use several types of different solvents, and may perform the surface treatment of a transparent base film independently with each solvent. Moreover, you may combine these methods.

  As described above, the solvent for surface treatment is preferably a ketone solvent. Examples of the ketone solvent include acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, cyclohexanone, and cyclopentanone. Of these, cyclohexanone and cyclopentanone are preferable. Examples of the solvent other than the ketone solvent include aromatic solvents such as xylene, cellosolve solvents such as ethyl cellosolve, ester solvents such as ethyl acetate and butyl acetate, and the like.

  As a method for applying the solvent onto the transparent substrate film, it can be formed by an appropriate method such as a doctor blade method, a gravure roll coater method, a dipping method, or a die coater method. In addition, the application amount of the solvent is not particularly limited, and can be appropriately selected depending on the types of the transparent base film and the coating liquid and the desired dissolution and / or swelling amount. If the time from solvent application to drying is too long, whitening may occur, so the time from application to drying is about 300 seconds or less, preferably 60 seconds or less.

  Moreover, after apply | coating the said solvent on a transparent base film and surface-treating, a solvent is dried. The drying can control the amount of dissolution and / or swelling of the transparent substrate film surface by applying a drying process such as an air knife or heating open after the surface treatment, if necessary. The amount of dissolution and / or swelling is preferably such that it does not dissolve the entire transparent substrate film and can impart an appropriate roughness that does not impair the transparency of the transparent substrate film.

  Next, a conductive layer is formed with a curable resin and a conductive inorganic filler on the solvent-treated surface of the transparent substrate film. In general, the conductive layer is preferably formed by applying a coating liquid composed of an inorganic thermosetting resin, a conductive inorganic filler, and a solvent, followed by drying and curing.

  Various types of curable resins can be used as the curable resin that is a binder for the conductive layer. However, when the thickness of the conductive layer is 0.5 μm or less, the ultraviolet curable resin causes oxygen inhibition. A curable resin is preferred. In particular, an inorganic thermosetting resin is preferable.

  Examples of the inorganic thermosetting resin include alkoxysilane and / or a condensate thereof. The alkoxysilane is thermally cured to form a polysiloxane structure. Specific examples of the alkoxysilane include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, Methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3 -Glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopro Trialkoxysilanes such as rutriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane , Diethyldimethoxysilane, diethyldiethoxysilane and the like. These alkoxysilanes can be used as a partial condensate thereof. Among these, tetraalkoxysilanes or partial condensates thereof are preferable. In particular, tetramethoxysilane, tetraethoxysilane or a partial condensate thereof is preferable.

  Examples of the conductive inorganic filler include ultrafine particles of conductive metal and / or metal oxide. Examples of the conductive metal and / or metal oxide include antimony oxide, selenium oxide, titanium oxide, tungsten oxide, tin oxide, antimony-doped tin oxide, phosphorus-doped tin oxide, zinc oxide, zinc antimonate, and tin-doped indium oxide. And metal oxide ultrafine particles having a high refractive index. As the metal oxide ultrafine particles, the main component is a metal oxide selected from tin, antimony, and indium, such as highly conductive antimony-doped tin oxide, phosphorus-doped tin oxide, zinc antimonate, and tin-doped indium oxide. Sol particles are preferred. Of these, antimony-doped tin oxide is preferable because it has good coating solution stability and sol reproducibility. The ultrafine particles preferably have an average particle size of 100 nm or less, more preferably 80 nm or less, and still more preferably 60 nm or less. When the average particle diameter exceeds 100 nm, generally haze increases and transparency tends to be inferior. In order to obtain a highly dispersible sol, a dispersion in a dispersion medium such as water, alcohol, ester or hydrocarbon is usually used.

  The ratio of the curable resin and the conductive inorganic filler is not particularly limited, but it is preferable to adjust the conductive layer to be formed so that the conductive inorganic filler is contained in an amount of about 40 to 98% by weight. By containing a conductive inorganic filler within the above range in the conductive layer, a conductive layer having good antistatic properties can be provided. Moreover, it is preferable also on adhesiveness. The proportion of the conductive inorganic filler in the conductive layer is more preferably 50 to 95% by weight.

  The solvent of the coating liquid used for forming the conductive layer is not particularly limited. For example, one or more of various solvents such as ketone solvents, aromatic solvents, ester solvents, alcohol solvents, ketone solvents, amide solvents, sulfoxide solvents, ether solvents, cellosolve solvents, etc. They can be used in appropriate combinations.

  Among the solvents, it is preferable to contain a ketone solvent from the viewpoint of forming a conductive layer with good adhesion.

  The solvent is preferably a mixed solvent containing a ketone solvent and an alcohol solvent. A solvent other than the ketone solvent is not particularly limited, but a solvent having a boiling point lower than that of the ketone solvent is preferable. In particular, when a ketone solvent is used as a mixed solvent with an alcohol solvent, the ketone solvent dissolves the transparent substrate film (especially the cellulose film) and improves the adhesion between the transparent substrate film and the conductive layer. The alcohol solvent is preferable because it has a high ability to dissolve the binder (curable resin) of the conductive layer. Examples of the alcohol solvent include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butanol, i-butanol, t-butanol and the like.

  In addition to the curable resin, the conductive inorganic filler, and the solvent, a curing catalyst can be used for the coating liquid. When the curable resin is an alkoxysilane, the curing catalyst includes organic acid catalysts such as formic acid, acetic acid, propionic acid, paratoluenesulfonic acid and methanesulfonic acid, tin-based catalysts such as dibutyltin laurate and tin octylate, Examples thereof include inorganic acid catalysts such as boric acid and phosphoric acid, and alkaline catalysts. Moreover, the various additives used for a conductive layer can be mix | blended with a coating liquid.

  The solid content concentration of the coating liquid is preferably adjusted to about 1 to 10% by weight, more preferably 1 to 3% by weight. The ratio of the curing method resin and the conductive inorganic filler in the coating liquid is adjusted so that the ratio of the conductive inorganic filler is about 40 to 95% by weight in the conductive layer formed by the coating liquid. Is preferred.

  The coating liquid is applied to the solvent-treated surface of the transparent substrate film, and then the solvent is dried and cured to form a conductive layer. Drying and curing are usually performed at a temperature of about 100 to 160 ° C. for about 1 to 120 minutes. When the alkoxysilane and / or condensate thereof used as the inorganic curable resin has ultraviolet curable properties, it can be cured with ultraviolet rays after heat curing. The coating method of the coating liquid is not particularly limited, and various methods such as a dipping method, a gravure coater method, a spin coating method, and a slot die coating method can be adopted. The thickness of the conductive layer is usually 0.01 to 0.5 μm, preferably 0.05 to 0.2 μm.

  A hard coat layer can be formed on the conductive layer. The resin for forming the hard coat layer is not particularly limited as long as it has excellent hard coat properties (showing a hardness of H or higher in the pencil hardness test of JIS K5400), has sufficient strength, and has excellent light transmittance. Absent. Examples thereof include thermosetting resins, thermoplastic resins, ultraviolet curable resins, electron beam curable resins, two-component mixed resins, and the like. Among these, an ultraviolet curable resin capable of efficiently forming a hard coat layer by a simple processing operation by a curing treatment by ultraviolet irradiation is preferable. Examples of the ultraviolet curable resin include polyester-based, acrylic-based, urethane-based, amide-based, silicone-based, and epoxy-based resins, and include ultraviolet curable monomers, oligomers, polymers, and the like. The UV curable resin preferably used includes, for example, those having an ultraviolet polymerizable functional group, and in particular, those containing an acrylic monomer or oligomer having 2 or more, particularly 3 to 6 functional groups. . Further, an ultraviolet polymerization initiator is blended in the ultraviolet curable resin.

  The transparent resin solution is applied by an appropriate method such as a bar coater such as a wire bar, a micro gravure coater, a die coater, casting, spin coating or phantom metalling. Examples of the solvent for dissolving the transparent resin include general solvents such as toluene, xylene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, isopropyl alcohol, and ethyl alcohol. The thickness of the hard coat layer is not particularly limited, but is preferably about 1 to 10 μm, particularly 2 to 5 μm.

The hard coat layer can be adjusted to a high refractive index by adding ultrafine particles of a high refractive index metal or metal oxide. Examples of the ultrafine particles having a high refractive index include ultrafine particles of metal oxides such as TiO ₂ , SnO ₂ , ZnO ₂ , ZrO ₂ , aluminum oxide, and zinc oxide. The average particle diameter of such ultrafine particles is usually preferably about 0.1 μm or less. High refractive index ultrafine particles can be dispersed almost uniformly in the hard coat layer.

  The surface of the hard coat layer can have a fine concavo-convex structure to impart antiglare properties. By making the surface of the hard coat layer uneven, antiglare properties due to light diffusion can be imparted. The provision of light diffusibility is also preferable for reducing the reflectance.

  The method for forming the fine concavo-convex structure on the surface is not particularly limited, and an appropriate method can be adopted. For example, the surface of the transparent substrate film used for forming the hard coat layer is preliminarily roughened by an appropriate method such as sand blasting, embossing roll, chemical etching, etc., and a method for providing a fine uneven structure on the film surface The method of forming the surface of the material itself for forming the hard coat layer into a fine concavo-convex structure can be given. Further, there is a method in which a hard coat layer is separately applied on the hard coat layer and a fine concavo-convex structure is imparted to the surface of the resin film layer by a transfer method using a mold or the like. Further, a method of imparting a fine concavo-convex structure by dispersing an inorganic or organic spherical or amorphous filler in the hard coat layer can be used. These fine concavo-convex structure forming methods may be formed as a layer in which two or more methods are combined to combine the fine concavo-convex structure surfaces in different states.

  As a method of forming the hard coat layer on the surface of the fine concavo-convex structure, a method of providing a hard coat layer containing an inorganic or organic spherical or amorphous filler in a dispersed manner is preferable from the viewpoint of formability. Examples of inorganic or organic spherical or amorphous fillers include crosslinked or uncrosslinked organic fine particles composed of various polymers such as PMMA (polymethyl methacrylate), polyurethane, polystyrene, melamine resin, glass, silica, alumina, and oxidation. Examples thereof include inorganic particles such as calcium, titania, zirconium oxide, and zinc oxide, and conductive inorganic particles such as tin oxide, indium oxide, cadmium oxide, antimony oxide, and a composite thereof. The average particle diameter of the filler (both primary particles and secondary particles) is preferably 0.5 to 10 μm, more preferably 1 to 5 μm. When the fine concavo-convex structure is formed with fine particles, the amount of fine particles used is preferably about 1 to 30 parts by weight with respect to 100 parts by weight of the resin.

  In addition, in formation of a hard-coat layer (anti-glare layer), additives, such as a leveling agent, a thixotropic agent, and an antistatic agent, can be contained. In forming a hard coat layer (antiglare layer), a thixotropic agent (silica, mica, etc. of 0.1 μm or less) can be included to easily form a fine relief structure with protruding particles on the surface of the antiglare layer. it can.

  An antireflection layer can be formed on the conductive layer or the hard coat layer. The method for forming the antireflection layer is not particularly limited, but a wet coating method using a low refractive index material is preferable because it is a simpler method than a vacuum deposition method or the like. Examples of the material for forming the antireflection layer include resin materials such as ultraviolet curable acrylic resins, hybrid materials in which inorganic fine particles such as colloidal silica are dispersed in the resin, tetraethoxysilane, titanium tetraethoxide, and the like. Examples include sol-gel materials using metal alkoxides. Each material uses a fluorine group-containing compound for imparting antifouling properties to the surface. From the viewpoint of scratch resistance, a low refractive index layer material having a high inorganic component content tends to be excellent, and a sol-gel material is particularly preferable. Sol-gel materials can be used after partial condensation.

For example, the antireflection layer forming material is a hydrolyzable alkoxysilane having a tetraalkoxysilane as a main component represented by the general formula (1): Si (OR) ₄ (wherein R represents a methyl group or an ethyl group). And siloxane oligomer (A) obtained by partially hydrolyzing and then polycondensing the polymer.

  The number average molecular weight of the siloxane oligomer (A) in terms of ethylene glycol is preferably 500 to 10,000. When the number average molecular weight of the siloxane oligomer (A) is less than 500, the coating and storage stability of the solution tends to decrease. On the other hand, when the number average molecular weight exceeds 10,000, the cured film has scratch resistance. There is a tendency that sufficient sex cannot be secured. The number average molecular weight of the siloxane oligomer (A) is more preferably 800 to 9000. By setting the number average molecular weight, adhesion to the hard coat layer can be improved, and peeling at the interface is less likely to occur.

  The siloxane oligomer (A) is obtained by placing hydrolyzable alkoxysilane in a large amount of alcohol solvent (for example, methanol, ethanol, etc.) and reacting it for several hours at room temperature in the presence of water and an acid catalyst (hydrochloric acid, nitric acid, etc.). Thus, it is obtained by condensation polymerization after hydrolysis. The degree of polymerization of the siloxane oligomer (A) can be controlled by adding the hydrolyzable alkoxysilane and water.

The hydrolyzable alkoxysilane is mainly composed of a tetraalkoxysilane represented by the general formula (1): Si (OR) ₄ (wherein R represents a methyl group or an ethyl group). Such tetraalkoxysilane is tetramethoxysilane and / or tetraethoxysilane, and is usually preferably 80 mol% or more of the hydrolyzable alkoxysilane.

  Examples of hydrolyzable alkoxysilanes used in addition to the tetraalkoxysilane include tetraalkoxysilanes such as tetrapropoxysilane and tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, Propyltrimethoxysilane, propyltriethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, pentyltrimethoxysilane, pentyltriethoxysilane, heptyltrimethoxysilane, heptyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, Dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecylto Methoxysilane, octadecyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyl Examples include trimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane.

  As the antireflection layer forming material, a silane coupling agent (B) having a fluoroalkyl group can be used. The silane coupling agent (B) is preferably used by blending with the siloxane oligomer (A).

As the silane coupling agent (B), for example, general formula (2): CF ₃ (CF ₂ ) _n CH ₂ CH ₂ — (NH) _m —Si (OR ² ) ₃ (wherein R ² is carbon A compound represented by formula 1-5, m is 0 or 1, and n is an integer of 0-12). Specifically, for example, trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, heptadecafluorodecyltri Examples thereof include ethoxysilane. Among these, the compound wherein n is 2 to 6 is preferable.

  In addition to the silane coupling agent (B), a fluorine compound (C) having a number average molecular weight in terms of polystyrene of 5000 or more and having a fluoroalkyl structure and a polysiloxane structure is included in order to improve the scratch resistance. It is done.

The fluorine compound (C) includes, for example, a perfluoroalkylalkoxysilane having an alkoxysilyl group that can be condensed by a sol-gel reaction, and a general formula (1): Si (OR ¹ ) ₄ (wherein R ¹ is the number of carbon atoms) A hydrolyzable alkoxysilane composed mainly of a tetraalkoxysilane represented by 1 to 5) in an alcohol solvent (for example, methanol, ethanol, etc.) or an organic acid (for example, oxalic acid) or an ester It is obtained by heating and polycondensation in the presence of a kind. In the obtained compound (C), a polysiloxane structure is introduced.

  In addition, the ratio of these reaction components is not particularly limited, but usually it is preferably about 1 to 100 mol, more preferably 2 to 10 mol of hydrolyzable alkoxysilane with respect to 1 mol of perfluoroalkylalkoxysilane. is there.

As perfluoroalkyl alkoxysilane, for example, general formula (2): CF ₃ (CF ₂ ) _n CH ₂ CH ₂ Si (OR ² ) ₃ (wherein R ² is an alkyl group having 1 to 5 carbon atoms) And n represents an integer of 0 to 12). Specifically, for example, trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, heptadecafluorodecyltri Examples thereof include ethoxysilane. Among these, the compound wherein n is 2 to 6 is preferable.

Tetraalkoxysilanes represented by the general formula (1): Si (OR ¹ ) ₄ (wherein R ¹ represents an alkyl group having 1 to 5 carbon atoms) include tetramethoxysilane, tetraethoxysilane, and tetrapropoxy. Examples thereof include silane and tetrabutoxysilane. Of these, tetramethoxysilane, tetraethoxysilane and the like are preferable.

  The silane coupling agent (B) and the fluorine compound (C) preferably have a hydroxyl group and / or an epoxy group. The hydroxyl group and / or epoxy group reacts with the polysiloxane structure of the siloxane oligomer (A), the silane coupling agent (B), or the fluorine compound (C) to increase the film strength of the cured film, resulting in scratch resistance. Can be further improved. The hydroxyl group and / or epoxy group may be introduced into the fluoroalkyl structure or may be introduced into the polysiloxane structure. A hydroxyl group and / or an epoxy group can be introduced by copolymerizing a compound having these functional groups.

  Further, a sol in which silica, alumina, titania, zirconia, magnesium fluoride, ceria or the like is dispersed in an alcohol solvent may be added to the antireflection layer. In addition, additives such as metal salts and metal compounds can be appropriately blended.

  The refractive index of the antireflection layer is preferably 1.35 to 1.49, more preferably 1.37 to 1.47.

  The formation method of the antireflection layer is not particularly limited, and can be formed by an appropriate method such as a doctor blade method, a gravure roll coater method, a dipping method, or a die coater method.

  The thickness of the antireflection layer is not particularly limited, and is usually about 80 to 150 nm on average. The thickness of the antireflection layer is determined so as to be near the target wavelength depending on the refractive index of the material to be used and the set wavelength of the incident light.

  An optical element can be bonded to the side of the conductive film where the conductive layer is not formed. Examples of the optical element include a polarizer. The polarizer is not particularly limited, and various types can be used. Examples of the polarizer include hydrophilic polymer films such as polyvinyl alcohol film, partially formalized polyvinyl alcohol film, and ethylene / vinyl acetate copolymer partially saponified film, and two colors such as iodine and dichroic dye. Examples thereof include polyene-based oriented films such as those obtained by adsorbing volatile substances and uniaxially stretched, polyvinyl alcohol dehydrated products and polyvinyl chloride dehydrochlorinated products. Among these, a polarizer composed of a polyvinyl alcohol film and a dichroic material such as iodine is preferable. The thickness of these polarizers is not particularly limited, but is generally about 5 to 80 μm.

  A polarizer obtained by dyeing a polyvinyl alcohol film with iodine and uniaxially stretching it can be produced, for example, by dyeing polyvinyl alcohol in an aqueous solution of iodine and stretching it 3 to 7 times the original length. If necessary, it can be immersed in an aqueous solution of boric acid or potassium iodide. Further, if necessary, the polyvinyl alcohol film may be immersed in water and washed before dyeing. In addition to washing the polyvinyl alcohol film surface with dirt and anti-blocking agents by washing the polyvinyl alcohol film with water, it also has the effect of preventing unevenness such as uneven coloring by swelling the polyvinyl alcohol film. is there. Stretching may be performed after dyeing with iodine, may be performed while dyeing, or may be dyed with iodine after stretching. The film can be stretched in an aqueous solution of boric acid or potassium iodide or in a water bath.

  The polarizer is usually used as a polarizing plate with a transparent protective film provided on one side or both sides. The transparent protective film is preferably excellent in transparency, mechanical strength, thermal stability, moisture shielding property, isotropy and the like. As the transparent protective film, the same material as the transparent substrate film exemplified above is used. The transparent protective film may be a transparent protective film made of the same polymer material on the front and back, or may be a transparent protective film made of a different polymer material or the like. Those excellent in transparency, mechanical strength, thermal stability, moisture barrier property and the like are preferably used. Further, the transparent protective film is often preferable as the optical anisotropy such as retardation is small. Triacetyl cellulose is optimal as the polymer for forming the transparent protective film. When the hard coat film is provided on one side or both sides of a polarizer (polarizing plate), the transparent base film of the hard coat film can also serve as a transparent protective film for the polarizer. The thickness of the transparent protective film is not particularly limited, but is generally about 10 to 300 μm.

  An anti-reflection polarizing plate in which a polarizing plate is laminated on a hard coat film may be a laminate of a hard protective film, a transparent protective film, a polarizer, and a transparent protective film, or a hard coat film with a polarizer and a transparent protective film. Those sequentially stacked may also be used.

  In addition, the surface of the transparent protective film on which the polarizer is not adhered may be a hard coat layer, a sticking prevention film or a treatment intended. The hard coat treatment is applied for the purpose of preventing scratches on the surface of the polarizing plate. For example, a transparent protective film with a cured film excellent in hardness, sliding properties, etc. by an appropriate ultraviolet curable resin such as acrylic or silicone is used. It can be formed by a method of adding to the surface of the film. Further, the anti-sticking treatment is performed for the purpose of preventing adhesion with an adjacent layer. The hard coat layer, the anti-sticking layer and the like can be provided on the transparent protective film itself, or can be provided separately from the transparent protective film as an optical layer.

  In addition, a hard coat layer, a primer layer, an adhesive layer, an adhesive layer, an antistatic layer, a conductive layer, a gas barrier layer, a water vapor barrier layer, a moisture barrier layer, etc. are inserted between the layers of the polarizing plate, or to the surface of the polarizing plate. You may laminate. Also. In the stage of forming each layer of the polarizing plate, for example, conductive particles or antistatic agents, various fine particles, plasticizers, and the like may be added to the material for forming each layer, mixed, or the like, if necessary.

  As an optical element, in practical use, an optical film in which another optical element (optical layer) is laminated on the polarizing plate can be used. The optical layer is not particularly limited. For example, for forming a liquid crystal display device such as a reflection plate, a semi-transmission plate, a retardation plate (including wavelength plates such as 1/2 and 1/4), and a viewing angle compensation film. One or more optical layers that may be used can be used. In particular, a reflective polarizing plate or a semi-transmissive polarizing plate in which a polarizing plate is further laminated with a reflecting plate or a semi-transmissive reflecting plate, an elliptical polarizing plate or a circular polarizing plate in which a retardation plate is further laminated on a polarizing plate, a polarizing plate A wide viewing angle polarizing plate in which a viewing angle compensation film is further laminated on a plate, or a polarizing plate in which a brightness enhancement film is further laminated on a polarizing plate is preferable. In an elliptically polarizing plate, a polarizing plate with optical compensation, etc., a hard coat film or the like is provided on the polarizing plate side.

  If necessary, various properties such as scratch resistance, durability, weather resistance, heat and humidity resistance, heat resistance, moisture resistance, moisture permeability, antistatic properties, conductivity, interlayer adhesion, mechanical strength, Processing for imparting a function or the like, or insertion or lamination of a functional layer can also be performed.

  A reflective polarizing plate is a polarizing plate provided with a reflective layer, and is used to form a liquid crystal display device or the like that reflects incident light from the viewing side (display side). Such a light source can be omitted, and the liquid crystal display device can be easily thinned. The reflective polarizing plate can be formed by an appropriate method such as a method in which a reflective layer made of metal or the like is provided on one surface of the polarizing plate via the transparent protective film or the like, if necessary.

  Specific examples of the reflective polarizing plate include those in which a reflective layer is formed by attaching a foil or a vapor deposition film made of a reflective metal such as aluminum on one side of a transparent protective film matted as necessary.

  The reflection plate can be used as a reflection sheet in which a reflection layer is provided on an appropriate film according to the transparent film instead of the method of directly applying to the transparent protective film of the polarizing plate. Since the reflective layer is usually made of metal, the usage form in which the reflective surface is covered with a transparent protective film, a polarizing plate or the like is used to prevent the reflectance from being lowered due to oxidation, and thus to maintain the initial reflectance for a long time. In addition, it is more preferable to avoid a separate attachment of the protective layer.

  The semi-transmissive polarizing plate can be obtained by using a semi-transmissive reflective layer such as a half mirror that reflects and transmits light with the reflective layer. A transflective polarizing plate is usually provided on the back side of a liquid crystal cell, and displays an image by reflecting incident light from the viewing side (display side) when a liquid crystal display device is used in a relatively bright atmosphere. In a relatively dark atmosphere, a liquid crystal display device or the like that displays an image using a built-in light source such as a backlight built in the back side of the transflective polarizing plate can be formed. In other words, the transflective polarizing plate is useful for forming a liquid crystal display device of a type that can save energy of using a light source such as a backlight in a bright atmosphere and can be used with a built-in light source even in a relatively dark atmosphere. It is.

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

  The elliptically polarizing plate is effectively used for black and white display without the above color by compensating (preventing) the coloration (blue or yellow) generated by the birefringence of the liquid crystal layer of the super twist nematic (STN) type liquid crystal display device. It is done. Further, the one in which the three-dimensional refractive index is controlled is preferable because it can compensate (prevent) coloring that occurs when the screen of the liquid crystal display device is viewed from an oblique direction. The circularly polarizing plate is effectively used, for example, when adjusting the color tone of an image of a reflective liquid crystal display device in which an image is displayed in color, and also has an antireflection function. Specific examples of the retardation plate include a birefringent film obtained by stretching a film made of an appropriate polymer such as polycarbonate, polyvinyl alcohol, polystyrene, polymethyl methacrylate, polypropylene, other polyolefins, polyarylate, and polyamide. And an alignment film of a liquid crystal polymer, and a liquid crystal polymer alignment layer supported by a film. The retardation plate may have an appropriate retardation according to the purpose of use, such as those for the purpose of compensating for various wavelength plates or birefringence of the liquid crystal layer, viewing angle, and the like. What laminated | stacked the phase difference plate and controlled optical characteristics, such as phase difference, etc. may be used.

  The elliptical polarizing plate and the reflective elliptical polarizing plate are obtained by laminating a polarizing plate or a reflective polarizing plate and a retardation plate in an appropriate combination. Such an elliptically polarizing plate or the like can also be formed by sequentially laminating them sequentially in the manufacturing process of the liquid crystal display device so as to be a combination of a (reflection type) polarizing plate and a retardation plate. An optical film such as a polarizing plate has an advantage that it can improve the production efficiency of a liquid crystal display device and the like because of excellent quality stability and lamination workability.

  The viewing angle 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 oblique direction rather than perpendicular to the screen. As such a viewing angle compensation phase difference plate, for example, a retardation film, an alignment film such as a liquid crystal polymer, or an alignment layer such as a liquid crystal polymer supported on a transparent substrate is used. A normal retardation plate uses a birefringent polymer film uniaxially stretched in the plane direction, whereas a retardation plate used as a viewing angle compensation film stretches biaxially in the plane direction. Birefringent polymer film, biaxially stretched film such as polymer with birefringence with a controlled refractive index in the thickness direction that is uniaxially stretched in the plane direction and stretched in the thickness direction, etc. Used. Examples of the inclined alignment film include a film obtained by bonding a heat shrink film to a polymer film and stretching or / and shrinking the polymer film under the action of the contraction force by heating, and a film obtained by obliquely aligning a liquid crystal polymer. Can be mentioned. The raw material polymer for the phase difference plate is the same as the polymer described in the previous phase difference plate, preventing coloration due to a change in the viewing angle based on the phase difference by the liquid crystal cell and expanding the viewing angle for good visual recognition. An appropriate one for the purpose can be used.

  Also, from the viewpoint of achieving a wide viewing angle with good visibility, an optically compensated phase difference in which a liquid crystal polymer alignment layer, in particular an optically anisotropic layer composed of a discotic liquid crystal polymer gradient alignment layer, is supported by a triacetylcellulose film. A plate can be preferably used.

  A polarizing plate obtained by bonding a polarizing plate and a brightness enhancement film is usually provided on the back side of a liquid crystal cell. The brightness enhancement film reflects a linearly polarized light with a predetermined polarization axis or a circularly polarized light in a predetermined direction when natural light is incident due to a backlight such as a liquid crystal display device or reflection from the back side, and transmits other light. In addition, a polarizing plate in which a brightness enhancement film is laminated with a polarizing plate allows light from a light source such as a backlight to enter to obtain transmitted light in a predetermined polarization state, and reflects light without transmitting the light other than the predetermined polarization state. The The light reflected on the surface of the brightness enhancement film is further inverted through a reflective layer or the like provided behind the brightness enhancement film and re-incident on the brightness enhancement film, and part or all of the light is transmitted as light having a predetermined polarization state. Luminance can be improved by increasing the amount of light transmitted through the enhancement film and increasing the amount of light that can be used for liquid crystal display image display or the like by supplying polarized light that is difficult to be absorbed by the polarizer. That is, when light is incident through the polarizer from the back side of the liquid crystal cell without using a brightness enhancement film, light having a polarization direction that does not coincide with the polarization axis of the polarizer is almost polarized. It is absorbed by the polarizer and does not pass through the polarizer. That is, although depending on the characteristics of the polarizer used, approximately 50% of the light is absorbed by the polarizer, and the amount of light that can be used for liquid crystal image display or the like is reduced accordingly, resulting in a dark image. The brightness enhancement film allows light having a polarization direction that is absorbed by the polarizer to be reflected once by the brightness enhancement film without being incident on the polarizer, and further inverted through a reflective layer provided on the rear side thereof. Repeatedly re-enter the brightness enhancement film, and the brightness enhancement film transmits only polarized light whose polarization direction is such that the polarization direction of light reflected and inverted between the two can pass through the polarizer. Therefore, light such as a backlight can be efficiently used for displaying an image on the liquid crystal display device, and the screen can be brightened.

  A diffusion plate may be provided between the brightness enhancement film and the reflective layer. The polarized light reflected by the brightness enhancement film is directed to the reflective layer or the like, but the installed diffuser plate uniformly diffuses the light passing therethrough and simultaneously cancels the polarized state and becomes a non-polarized state. That is, the diffuser plate returns the polarized light to the original natural light state. The light in the non-polarized state, that is, the natural light state is directed toward the reflection layer and the like, reflected through the reflection layer and the like, and again passes through the diffusion plate and reenters the brightness enhancement film. Thus, while maintaining the brightness of the display screen by providing a diffuser plate that returns polarized light to the original natural light state between the brightness enhancement film and the reflective layer, etc., the brightness unevenness of the display screen is reduced at the same time, A uniform and bright screen can be provided. By providing such a diffuser plate, it is considered that the first incident light has a moderate increase in the number of repetitions of reflection, and in combination with the diffusion function of the diffuser plate, a uniform bright display screen can be provided.

  The brightness enhancement film has a characteristic of transmitting linearly polarized light having a predetermined polarization axis and reflecting other light, such as a multilayer thin film of dielectric material or a multilayer laminate of thin film films having different refractive index anisotropies. Such as an alignment film of a cholesteric liquid crystal polymer or an alignment liquid crystal layer supported on a film substrate, which reflects either left-handed or right-handed circularly polarized light and transmits other light. Appropriate things, such as a thing, can be used.

  Therefore, in the brightness enhancement film of the type that transmits linearly polarized light having the predetermined polarization axis as described above, the transmitted light is incident on the polarizing plate with the polarization axis aligned as it is, thereby efficiently transmitting while suppressing absorption loss due to the polarizing plate. Can be made. On the other hand, in a brightness enhancement film of a type that transmits circularly polarized light such as a cholesteric liquid crystal layer, it can be directly incident on a polarizer, but from the point of suppressing absorption loss, the circularly polarized light is linearly polarized through a retardation plate. It is preferable to make it enter into a polarizing plate. Note that circularly polarized light can be converted to linearly polarized light by using a quarter wave plate as the retardation plate.

  A retardation plate that functions as a quarter-wave plate in a wide wavelength range such as a visible light region exhibits, for example, a retardation layer that functions as a quarter-wave plate for light-color light having a wavelength of 550 nm and other retardation characteristics. It can be obtained by a method of superposing a retardation layer, for example, a retardation layer functioning as a half-wave plate. Therefore, the retardation plate disposed between the polarizing plate and the brightness enhancement film may be composed of one or more retardation layers.

  In addition, the cholesteric liquid crystal layer can also be obtained by reflecting circularly polarized light in a wide wavelength range such as a visible light region by combining two or more layers having different reflection wavelengths and having an overlapping structure. Based on this, transmitted circularly polarized light in a wide wavelength range can be obtained.

  Further, the polarizing plate may be formed by laminating a polarizing plate and two or three or more optical layers like the above-described polarization separation type polarizing plate. Therefore, a reflective elliptical polarizing plate or a semi-transmissive elliptical polarizing plate in which the above-mentioned reflective polarizing plate or transflective polarizing plate and a retardation plate are combined may be used.

  Lamination of a hard coat film or the like to the optical element, and further lamination of various optical layers to the polarizing plate can be performed by a method of sequentially laminating separately in the manufacturing process of a liquid crystal display device or the like. Those previously laminated are excellent in quality stability, assembly work, etc., and have the advantage of improving the manufacturing process of liquid crystal display devices and the like. For the lamination, an appropriate adhesive means such as an adhesive layer can be used. When adhering the polarizing plate and other optical films, their optical axes can be set at an appropriate arrangement angle in accordance with the target retardation characteristics.

  An adhesive layer for adhering to other members such as a liquid crystal cell can be provided on at least one surface of the optical element described above. The pressure-sensitive adhesive forming the pressure-sensitive adhesive layer is not particularly limited. For example, an acrylic polymer, silicone-based polymer, polyester, polyurethane, polyamide, polyether, fluorine-based or rubber-based polymer is appropriately selected. Can be used. In particular, those having excellent optical transparency such as an acrylic pressure-sensitive adhesive, exhibiting appropriate wettability, cohesiveness, and adhesive pressure-sensitive adhesive properties, and being excellent in weather resistance, heat resistance and the like can be preferably used.

  In addition to the above, in terms of prevention of foaming and peeling phenomena due to moisture absorption, deterioration of optical properties and liquid crystal cell warpage due to differences in thermal expansion, etc., as well as formability of liquid crystal display devices with high quality and excellent durability An adhesive layer having a low moisture absorption rate and excellent heat resistance is preferred.

  The adhesive layer is, for example, natural or synthetic resins, in particular, tackifier resins, fillers or pigments made of glass fibers, glass beads, metal powders, other inorganic powders, colorants, antioxidants, etc. It may contain an additive to be added to the adhesive layer. Moreover, the adhesion layer etc. which contain microparticles | fine-particles and show light diffusibility may be sufficient.

  Attachment of the adhesive layer to an optical element such as a polarizing plate or an optical film can be performed by an appropriate method. For example, a pressure sensitive adhesive solution of about 10 to 40% by weight in which a base polymer or a composition thereof is dissolved or dispersed in a solvent composed of an appropriate solvent alone or a mixture such as toluene and ethyl acetate is prepared. There is a method of attaching it directly on the optical element by an appropriate development method such as a casting method or a coating method, or a method of forming an adhesive layer on the separator according to the above and transferring it onto the optical element. can give. The pressure-sensitive adhesive layer can also be provided as an overlapping layer of different compositions or types in each layer. The thickness of the pressure-sensitive adhesive layer can be appropriately determined according to the purpose of use and adhesive force, and is generally 1 to 500 μm, preferably 5 to 200 μm, particularly preferably 10 to 100 μm.

  On the exposed surface of the adhesive layer, a separator is temporarily attached and covered for the purpose of preventing contamination until it is put to practical use. Thereby, it can prevent contacting an adhesion layer in the usual handling state. As the separator, except for the above thickness conditions, for example, a suitable thin leaf body such as a plastic film, rubber sheet, paper, cloth, non-woven fabric, net, foam sheet, metal foil, laminate thereof, and the like, silicone type or Appropriate conventional ones such as those coated with an appropriate release agent such as long-chain alkyl, fluorine-based, or molybdenum sulfide can be used.

  In the present invention, each layer such as a polarizer, a transparent protective film, an optical layer, or an adhesive layer that forms the optical element described above may be, for example, a salicylic acid ester compound, a benzophenol compound, a benzotriazole compound, or a cyanoacrylate. It may be a compound having an ultraviolet absorbing ability by a method such as a method of treating with an ultraviolet absorber such as a compound based on nickel or a nickel complex salt compound.

  The optical element provided with the hard coat film of the present invention can be preferably used for forming various devices such as a liquid crystal display device. The liquid crystal display device can be formed according to the conventional method. That is, a liquid crystal display device is generally formed by appropriately assembling components such as a liquid crystal cell, an optical element, and an illumination system as necessary, and incorporating a drive circuit. There is no limitation in particular except for the point which uses an element, and it can be based on the past. As the liquid crystal cell, any type such as a TN type, an STN type, or a π type can be used.

  An appropriate liquid crystal display device such as a liquid crystal display device in which the optical element is arranged on one side or both sides of a liquid crystal cell, or a backlight or a reflector used in an illumination system can be formed. In that case, the optical element according to the present invention can be installed on one side or both sides of the liquid crystal cell. When optical elements are provided on both sides, they may be the same or different. Further, when forming a liquid crystal display device, for example, a single layer or a suitable part such as a diffusion plate, an antiglare layer, an antireflection film, a protective plate, a prism array, a lens array sheet, a light diffusion plate, a backlight, Two or more layers can be arranged.

  Next, an organic electroluminescence device (organic EL display device) will be described. Generally, in an organic EL display device, a transparent electrode, an organic light emitting layer, and a metal electrode are sequentially laminated on a transparent substrate to form a light emitter (organic electroluminescent light emitter). 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 and the like and a light emitting layer made of a fluorescent organic solid such as anthracene, Alternatively, a structure having various combinations such as a laminate of such a light emitting layer and an electron injection layer composed of a perylene derivative or the like, or a laminate of these hole injection layer, light emitting layer, and electron injection layer is known. It has been.

  In organic EL display devices, holes and electrons are injected into the organic light-emitting layer by applying a voltage to the transparent electrode and the metal electrode, and the energy generated by recombination of these holes and electrons excites the phosphor material. Then, light is emitted on the principle that the excited fluorescent material emits light when returning to the ground state. The mechanism of recombination in the middle is the same as that of a general diode, and as can be predicted from this, the current and the emission intensity show strong nonlinearity with rectification with respect to the applied voltage.

  In an organic EL display device, in order to extract light emitted from the organic light emitting layer, at least one of the electrodes must be transparent, and a transparent electrode usually formed of a transparent conductor such as indium tin oxide (ITO) is used as an anode. It is used as. On the other hand, in order to facilitate electron injection and increase luminous efficiency, it is important to use a material having a small work function for the cathode, and usually metal electrodes such as Mg—Ag and Al—Li are 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 transmits light almost completely like the transparent electrode. As a result, light that is incident from the surface of the transparent substrate at the time of non-light emission, passes through the transparent electrode and the organic light emitting layer, and is reflected by the metal electrode is again emitted to the surface side of the transparent substrate. The display surface of the organic EL display device looks like a mirror surface.

  In an organic EL display device comprising an organic electroluminescent light emitting device comprising a transparent electrode on the surface side of an organic light emitting layer that emits light upon application of a voltage and a metal electrode on the back side of the organic light emitting layer, the surface of the transparent electrode While providing a polarizing plate on the side, a retardation plate can be provided between the transparent electrode 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, there is an effect that the mirror surface of the metal electrode is not visually recognized by the polarization action. In particular, the mirror surface of the metal electrode can be completely shielded by configuring the retardation plate with a quarter-wave plate and adjusting the angle formed by the polarization direction of the polarizing plate and the retardation plate to π / 4. .

  That is, only the linearly polarized light component of the external light incident on the organic EL display device is transmitted by the polarizing plate. This linearly polarized light becomes generally elliptically polarized light by the phase difference plate, but becomes circularly polarized light particularly when the phase difference plate is a quarter wavelength plate and the angle between the polarization direction of the polarizing plate and the phase difference plate is π / 4. .

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

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In each example, parts and percentages are by weight.

Example 1
(Solvent treatment of transparent substrate film)
Cyclohexanone was applied to a 80 μm thick triacetylcellulose film with a # 7 wire bar. After the application, the hair dryer was applied with cold air at a medium strength and dried for 30 seconds.

(Coating of conductive layer)
5 parts of tetraalkoxysilane (polysiloxane thermosetting component) and 95 parts of antimony-doped tin oxide ultrafine particles having an average particle size of 10 to 60 nm were mixed with a solvent to prepare a coating liquid having a solid content concentration of 1.5%. . A solvent containing 20% cyclohexanone, 5% methyl ethyl ketone, 10% methanol, 45% ethanol, and 20% propylene glycol monomethyl ether was used.

On the triacetyl cellulose film having a thickness of 80 μm subjected to the above solvent treatment, the coating solution is applied with a # 10 wire bar, and heated and cured in an environment of 130 ° C. for 2 minutes to obtain a conductive layer (refractive index). : 1.59, film thickness 86 nm) to form a conductive film. The surface resistance value of the obtained conductive layer was 1 × 10 ¹¹ Ω / □.

(Creation of hard coat film)
On the conductive layer of the conductive film, a hard coat film was prepared in which a hard coat layer having a surface with fine irregularities was provided. For the formation of the hard coat layer, a coating solution containing ZnO ₂ ultrafine particles (particle size 0.01 to 0.1 μm) and an ultraviolet curable acrylic resin as a binder (solid content 40 wt%, ZnO ₂ / binder = 42 / 58, weight ratio) was applied onto the conductive layer using a # 8 wire bar, dried at 120 ° C. for 3 minutes, and then irradiated with ultraviolet rays with a UV lamp to form a hard coat layer (refractive index: 1.71, A film thickness of 2.2 μm) was formed.

Comparative Example 1
In Example 1, a conductive film was produced in the same manner as in Example 1 except that the solvent treatment was not performed on the transparent substrate film. A hard coat layer was formed in the same manner as in Example 1.

  The following evaluation was performed about the electroconductive film which formed the hard-coat layer obtained in the Example and the comparative example. The results are shown in Table 1.

(Adhesion)
According to the cross-cut peel test described in JIS K-5400, 100 pieces of 1 mm × 1 mm cross hatches were put on the surface of the hard coat layer, and the number x peeled when peeled off with a cellophane tape was “x / 100”. Expressed in

  Evaluation was performed before and after humidification. After humidification, each of conditions 1: humidified at 40 ° C. and 92% RH for 2 hours and conditions 2: humidified at 80 ° C. and 90% RH for 2 hours.

表１から、実施例では耐熱・耐湿環境下においても密着性に優れていることが認められる。

From Table 1, it is recognized that in the examples, the adhesiveness is excellent even in a heat and humidity resistant environment.

(Creation of antireflection film)
An antireflection film having an antireflection layer provided on the hard coat layer of the hard coat film was prepared. For the formation of the antireflection layer, a mixture of a fluorine compound having a fluoroalkyl structure and a polysiloxane structure and a siloxane oligomer was used. This was coated by a slot die coating method and cured by heating in an environment of 120 ° C. for 3 minutes to form a 0.1 μm antireflection layer.

  For the antireflection layer of the antireflection film, the same adhesion evaluation as described above was performed. In either case, good results were obtained.

Claims (12)

In producing a conductive film in which a conductive layer formed of a curable resin and a conductive inorganic filler is laminated on at least one side of a transparent substrate film,
After applying a solvent capable of dissolving the material of the transparent substrate film to the transparent substrate film and drying,
A method for producing a conductive film, comprising forming a conductive layer on a solvent-treated surface of a transparent substrate film.   The method for producing a conductive film according to claim 1, wherein the solvent is a ketone solvent.   The method for producing a conductive film according to claim 2, wherein the ketone solvent is cyclohexanone and / or cyclopentanone.   The conductive layer is formed by applying a coating liquid containing a curable resin, a conductive inorganic filler, and a solvent to the solvent-treated surface of the transparent base film, followed by drying and curing. 4. A method for producing a conductive film according to any one of 3 above.   The method for producing a conductive film according to claim 1, wherein the curable resin is an inorganic thermosetting resin.   The method for producing a conductive film according to claim 1, wherein the transparent substrate film is a triacetyl cellulose film.   The electroconductive film obtained by the manufacturing method in any one of Claims 1-6.   A conductive film, wherein a hard coat layer is formed on the conductive layer of the conductive film according to claim 7.   The conductive film according to claim 8, wherein the surface of the hard coat layer has an uneven shape.   An antireflection layer is formed on the conductive layer of the conductive film according to claim 7.   The optical element in which the electroconductive film in any one of Claims 7-10 is provided in the single side | surface or both surfaces of the optical element. The image display apparatus carrying the electroconductive film in any one of Claims 7-10, or the optical element of Claim 11.