JP2006178041A - Antireflective diffusion plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antireflective diffusion plate for a transmissive screen having excellent resolution, contrast, scratch resistance and pencil hardness and requiring no protective panel on the front face. <P>SOLUTION: The diffusion plate 43 comprises a diffusion plate body 43a, a hard coat layer 43b formed on one principal surface of the diffusion plate body 43a, and an antireflective layer 43c formed on the hard coat layer 43b. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an antireflection diffusion plate for a transmissive screen used in a rear projection type projection television. More specifically, the present invention relates to an antireflection diffusion plate that does not require a protective panel on the front surface, suppresses white blurring, improves light transmission, and has excellent scratch resistance and pencil hardness.

  In recent years, rear projection type projection televisions have been developed as devices suitable for large screen display. This rear projection type projection television is a device that modulates light emitted from a light source with a video projection device such as a liquid crystal panel, and magnifies the obtained video light with a projection lens and projects it onto a transmissive screen. This transmissive screen has a configuration in which a Fresnel lens sheet, a lenticular lens sheet, and a diffusion plate are sequentially arranged from the image light projection side.

  The Fresnel lens sheet is used to uniformly brighten the entire screen by directing the image light from the image projection device in the vertical direction (the direction toward the observer, that is, the normal direction of the screen surface). The lenticular lens sheet is configured by arranging cylindrical lens groups, and refracts the image light in the horizontal direction to widen the horizontal viewing angle, that is, the observable area so that many people can observe. . The diffusion plate has an effect of diffusing the image light in the vertical direction and simultaneously forms an image on the screen.

  A diffusion plate used in a conventional transmission screen has a base material made of any resin such as acrylic resin (PMMA), polycarbonate resin (PC), acrylic-styrene copolymer resin (MS), and powder as a diffusion material. Glass, finely pulverized glass fibers, titanium oxide, calcium carbonate, silicon dioxide (silica), aluminum oxide, inorganic fine powders such as various clays, or crosslinked polymer resin fine particles are mixed. As a method of manufacturing a diffusion plate containing a diffusion material, a method of kneading the diffusion material when the resin is molded into a plate shape, or a method of coating a plate-shaped body previously molded from the resin by using the diffusion material as a coating material is used. And a method of providing a diffusion layer by coating.

  Since the diffusion plate uses fine particles as a diffusion material, the surface on the viewer side has irregularities due to the fine particles, and an anti-glare effect that suppresses reflection on the surface can be obtained. There is a problem that so-called white blur occurs due to scattering. In addition, since the surface of the diffusion plate is not strong enough, the surface of the diffusion plate cannot be the outermost surface of a rear projection type projection television, and a protective panel must be provided on the viewer side of the transmission type screen. was there.

  Patent Document 1 discloses a technique in which a base film provided with an antireflection layer is provided on the surface of a diffusion plate via an adhesive layer. This technique is intended to suppress fluctuations such as warpage of screen components due to ambient temperature differences, and white blurring is suppressed. However, in this diffusing plate, since the substrate film is interposed, there is a problem that the light transmittance is lowered and the mechanical strength such as pencil hardness is inferior.

JP 2001-5103 A

  The present invention has been made in view of the above points, and suppresses white blurring, improves light transmission, is excellent in scratch resistance and pencil hardness, and does not require a protective panel on the front surface. An object of the present invention is to provide an antireflection diffuser for a screen.

  The inventor has found that the above object can be achieved by having a hard coat layer and an antireflection layer on one side of the diffusion plate without using a base film layer, and completed the present invention.

  The antireflection diffusion plate of the present invention comprises a diffusion plate body, a hard coat layer formed on one main surface of the diffusion plate body, and an antireflection layer formed on the hard coat layer. It is characterized by that.

  In the antireflection diffusion plate of the present invention, it is preferable that the diffusion plate main body has diffusion particles dispersed therein. Moreover, in the antireflection diffusion plate of the present invention, it is preferable to have an antistatic layer between the antireflection layer and the diffusion plate body.

  The screen for rear projection display according to the present invention includes the antireflection diffusion plate, a lenticular lens member disposed on the diffusion plate main body side of the antireflection diffusion plate, and a Fresnel disposed so as to face the lenticular lens member. And a lens member.

  The method for producing an antireflection diffuser plate according to the present invention includes a step of forming an antireflection layer and a hard coat layer on a base material to produce a transfer material, and a layer laminated surface of the transfer material as one main surface of the diffusion plate body And a step of transferring to the substrate.

  In the method for producing an antireflection diffusion plate of the present invention, it is preferable that the step of producing a transfer material includes a step of forming an antistatic layer between the base material and the hard coat layer.

  The antireflection diffuser of the present invention can be used for a transmissive screen diffuser used in rear projection type projection televisions, etc., and it is not necessary to provide a protective panel on the front surface. It has the advantages of improved properties and excellent scratch resistance and pencil hardness.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram showing a schematic configuration of a display such as a rear projection type projection television having a transmission type screen provided with an antireflection diffusion plate according to an embodiment of the present invention.

  In this display, a video projection device 2 such as a liquid crystal panel is arranged at a subsequent stage of the light source 1 (a position preceding the light path in the light traveling direction). A projection lens 3 is disposed at the subsequent stage of the video projection device 2. Further, a transmissive screen 4 is disposed at the rear stage of the projection lens 3. In the display having such a configuration, the light emitted from the light source 1 is optically modulated by the video projection device 2, and the obtained video light is enlarged by the projection lens 3 and projected onto the transmission screen 4. An image formed on the surface of the transmission screen 4 is visually recognized by an observer.

  The transmissive screen 4 includes a Fresnel lens sheet 41 that directs the image light from the image projection device in the vertical direction (the direction toward the observer, that is, the normal direction of the screen surface), and the horizontal direction from the image light projection side. A lenticular lens sheet 42 that refracts image light and widens the viewing angle in the horizontal direction and a diffusion plate 43 that has an effect of diffusing the image light in the vertical direction and simultaneously forms an image on the screen are sequentially arranged. It has a configuration.

  As shown in FIG. 2, the diffusion plate 43 includes a diffusion plate main body 43a, a hard coat layer 43b formed on one main surface of the diffusion plate main body 43a, and an antireflection coating formed on the hard coat layer 43b. And the layer 43c. In the diffusion plate 43, the antireflection layer 43c is composed of a single layer or a plurality of layers containing at least one low refractive index layer. The simplest multi-layer configuration is a two-layer configuration of a low refractive index layer and a high refractive index layer. Moreover, there is no restriction | limiting in particular about the number of layers of a low refractive index layer and / or a high refractive index layer, According to the characteristic requested | required, it sets suitably. An antistatic layer may be provided between the antireflection layer 43c and the diffuser plate body 43a. In this case, the hard coat layer 43b or the high refractive index layer and the antistatic layer may be used.

  The present invention will be described in detail. The diffusion plate main body 43a of the antireflection diffusion plate of the present invention is made of any resin such as acrylic resin (PMMA), polycarbonate resin (PC), acrylic-styrene copolymer resin (MS), and the resin is powder glass. It is preferable to mix finely pulverized glass fibers, titanium oxide, calcium carbonate, silicon dioxide (silica), aluminum oxide, fine particles such as inorganic fine particles such as clay, and fine particle diffusion materials such as crosslinked polymer resin fine particles. The diffusion plate body 43a can be manufactured by kneading the diffusion material when the resin is molded into a plate shape. In addition, as the diffusing plate main body 43a, it is possible to use a material in which fine particles are fixed on the surface of the optical base material with a binder and diffused on the surface, or a surface on which the surface of the optical base material is embossed.

  As the hard coat layer 43b, a commercially available silicone hard coat, (meth) acrylic hard coat, epoxy hard coat, urethane hard coat, epoxy acrylate hard coat, urethane acrylate hard coat, or the like is used. be able to. In addition, the hard coat layer 43b can also be formed by applying a coating liquid containing a polyfunctional monomer and a polymerization initiator to the underlayer and polymerizing the polyfunctional monomer. The thickness of the hard coat layer 43b is usually set to 0.1 μm to 10 μm.

  The antireflection layer 43c is composed of a single layer or a plurality of layers containing at least one low refractive index layer.

  The low refractive index layer has a refractive index lower than the refractive index of the lower layer. The thickness of the low refractive index layer is usually 50 nm to 1000 nm, preferably 50 nm to 500 nm, more preferably 60 nm to 200 nm.

  In the low refractive index layer, in consideration of mechanical properties such as scratch resistance, the silica particles are 30% by mass to 95% by mass, preferably 40% by mass to 90% by mass, and more preferably 50% by mass to 80% by mass. %included. When the content of the silica particles is 30% by mass or more, an antireflection layer having a sufficiently high strength can be obtained, and a low refractive index layer having a low refractive index can be obtained by a minute gap between the silica particles. There are cases where it is possible.

  The shape of the silica particles in the low refractive index layer is not particularly limited, and it is spherical, plate-like, needle-like, a plurality of these shapes connected to form a chain or branched chain, and a plurality of these The thing of the shape of agglomerated and it became the bunch of grapes etc. can be used. The “chain” includes those generally called “(short) fiber” and “pearl necklace”.

  In the present specification, the spherical silica particles are those having a ratio of the largest diameter (major axis) of the silica particles to the smallest diameter (minor axis) in the direction perpendicular to the major axis of less than 1.5. Others are called non-spherical silica particles. The shape of the silica particles can be confirmed by observing with a transmission electron microscope, for example.

  Among these, when a non-spherical material, that is, a plate shape, a needle shape, a chain shape, a branched chain shape, or a bunch of grapes is used, minute voids are easily generated between adjacent particles, and the refractive index is low. Since an antireflection layer can be obtained, it is preferable.

When spherical, needle-like or plate-like silica particles are used, the average particle diameter is preferably in the range of 10 nm to 200 nm in consideration of the strength of the antireflection layer, the surface roughness (Ra) of the layer, and the occurrence of haze. . The average particle diameter is a value given by the formula of average particle diameter = (2720 / specific surface area) from the specific surface area (m ² / g) measured by the nitrogen adsorption method (BET method).

  What can be used in the case of using chain-like and / or branched chain-like silica particles is that the strength of the antireflection layer, the surface roughness (Ra) of the layer, the occurrence of haze, the resolution of the fluoroscopic image, and the visibility. In consideration, a plurality of silica particles having an average particle diameter of 5 nm to 30 nm, more preferably 10 nm to 30 nm are continuously arranged until they have an average length of 30 nm to 200 nm. The average particle diameter is a value obtained in the same manner as described above. The average length is a value measured by a dynamic light scattering method and is generally equivalent to a value called a particle diameter by a dynamic light scattering method. Considering the strength of the antireflection layer, the surface roughness (Ra) of the layer, the occurrence of haze, the resolution of the fluoroscopic image, and the visibility, the average length of the silica particles is preferably 30 nm to 200 nm.

  Among these silica particles, when a chain and / or branched chain is used, the silica particles are likely to be present in the vicinity of the surface of the antireflection layer, and the silica particles are less likely to fall off from the surface of the antireflection layer. Moreover, since the number of points per silica particle that come into contact with and bind to other silica particles increases, the strength of the antireflection layer is increased, which is preferable. Of these, those having a two-dimensional or three-dimensionally curved shape are most preferable. Examples of such silica particles include “Snowtex (registered trademark) -OUP”, “Snowtex (registered trademark) -UP”, and “Snowtex (registered trademark) -PS-” manufactured by Nissan Chemical Industries, Ltd. "S", "Snowtex (registered trademark) -PS-SO", "Snowtex (registered trademark) -PS-M", "Snowtex (registered trademark) -PS-MO", " Fine Cataloid (registered trademark) F-120 "and the like. These chain-like silicas are composed of a dense silica main skeleton and have a chain-like and three-dimensionally curved shape.

  The content of the chain-like and / or branched chain-like silica particles is not particularly limited. If a relatively large amount is used, an antireflection layer having a large volume of voids therein and a low refractive index is used. Unevenness on the surface of the layer can be reduced. The preferable content of the chain-like and / or branched chain-like silica particles is 90% by mass or less, more preferably 70% by mass in the low refractive index layer in consideration of the surface roughness (Ra) of the antireflection layer. Hereinafter, it is more preferably 50% by mass or less.

  The antireflection layer 43c is preferably formed by a coating method, and can be formed by coating the above-described silica particles and a binder or additive described below on a transfer material substrate in a state of being dispersed in a dispersion medium. The dispersion medium to be used is not limited as long as the silica particles and the binder and additives described below are stably dispersed.

  Specific examples of the dispersion medium include water; alcohols such as monohydric alcohols having 1 to 6 carbon atoms, dihydric alcohols having 1 to 6 carbon atoms, and glycerin; formamide, N-methylformamide, N-ethylformamide, N , N-dimethylformamide, N, N-diethylformamide, N-methylacetamide, N-ethylacetamide, N, N-dimethylacetamide, N, N-diethylacetamide, N-methylpyrrolidone and other amides; tetrahydrofuran, diethyl ether , Ethers such as di (n-propyl) ether, diisopropyl ether, diglyme, 1,4-dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol dimethyl ether; ethylene glycol monomethyl ether Alkanol ethers such as tellurium, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monobutyl ether; ethyl formate, acetic acid Esters such as methyl, ethyl acetate, ethyl lactate, ethylene glycol monomethyl ether acetate, ethylene glycol diacetate, propylene glycol monomethyl ether acetate, diethyl carbonate, ethylene carbonate, propylene carbonate, γ-butyrolactone, ethyl acetoacetate; acetone, methyl ethyl ketone, Methyl propyl ketone, methyl (n-butyl) ketone , Methyl isobutyl ketone, methyl amyl ketone, acetylacetone, cyclopentanone, cyclohexanone and other ketones; acetonitrile, propionitrile, n-butyronitrile, isobutyronitrile and other nitriles; dimethyl sulfoxide, dimethyl sulfone, sulfolane, etc. are preferred Used for.

  More preferred dispersion media are monohydric alcohols having 1 to 6 carbon atoms; and ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monopropyl ether, propylene glycol monopropyl Alkanol ethers such as ether, ethylene glycol monobutyl ether, propylene glycol monobutyl ether; acetone, methyl ethyl ketone, methyl propyl ketone, methyl (n-butyl) ketone, methyl isobutyl ketone, methyl amyl ketone, acetylacetone, cyclopentanone, cyclohexanone, etc. Ketones.

  These dispersion media may be mixed as long as the object of the present invention is not impaired, and other arbitrary solvents or additives may be mixed.

  The concentration of the silica particles in the dispersion is preferably 0.01% by mass to 10% by mass from the viewpoint of providing good film formability, that is, considering that the desired thickness can be maintained and the coating solution viscosity. More preferably, it is 0.05 mass%-5 mass%.

  In applying the dispersion liquid to the substrate, it is also effective to add a known leveling agent or a binding aid (coupling agent) in order to enhance the application performance and the adhesion to the diffusion plate body 43a.

  The antireflection layer 43c is characterized by containing a binder in addition to the silica particles. As the binder, those that chemically bond to silica particles or those that do not chemically bond to silica particles can be used, but those that chemically bond to silica particles are preferred. The binder may be used alone or in combination. The following are mentioned as a preferable binder.

(1) Hydrolyzable silanes, or partial hydrolysates and dehydrated condensates thereof. Preferably, tetramethoxysilane, tetraethoxysilane, tetra (n-propoxy) silane, tetra (i-propoxy) silane, tetra (n-butoxy) silane, trimethoxysilane, triethoxysilane, methyltrimethoxysilane, methyltri Examples include ethoxysilane, ethyltrimethoxysilane, and ethyltriethoxysilane.

(2) Hydrolyzable silanes having both a polymerizable functional group and a functional group capable of forming a covalent bond with silica particles in the same molecule, or a partially hydrolyzed product or a dehydrated condensate thereof. . Preferable examples include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, and 3-acryloxypropyltriethoxysilane.

(3) Silicic acid, trimethylsilanol, triphenylsilanol, dimethylsilanediol, diphenylsilanediol, silanol terminated polydimethylsiloxane, silanol terminated polydiphenylsiloxane, silanol terminated polymethylphenylsiloxane, silanol terminated polymethyl ladder siloxane, silanol terminated poly Examples thereof include silicon compounds containing silanol groups such as phenyl ladder siloxane and octahydroxy octasilsesquioxane.

(4) Water glass, sodium orthosilicate, potassium orthosilicate, lithium orthosilicate, sodium metasilicate, potassium metasilicate, lithium metasilicate, tetramethylammonium orthosilicate, tetrapropylammonium orthosilicate, tetramethylammonium metasilicate, metasilicate Examples thereof include activated silica obtained by bringing a silicate such as tetrapropylammonium into contact with an acid or an ion exchange resin.

(5) Polyethers such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol; amides such as polyacrylamide derivatives, polymethacrylamide derivatives, poly (N-vinylpyrrolidone), poly (N-acylethyleneimine), polyvinyl Examples include esters such as alcohol, polyvinyl acetate, polyacrylic acid derivatives, polymethacrylic acid derivatives, and polycaprolactone; and organic polymers such as polyimides, polyurethanes, polyureas, and polycarbonates. These organic polymers may have a polymerizable functional group at the terminal or main chain.

(6) alkyl (meth) acrylate, alkylene bis (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, Examples thereof include polymerizable monomers such as dipentaerythritol hexa (meth) acrylate, alkylene bisglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol triglycidyl ether, pentaerythritol tetraglycidyl ether, and vinylcyclohexene diepoxide. Here, (meth) acrylate refers to both acrylate and methacrylate.

(7) Well-known curable resin etc. are mentioned. For example, (meth) acrylic UV curable resin, moisture curable silicone resin, thermosetting silicone resin, epoxy resin, phenoxy resin, novolac resin, silicone acrylate resin, melamine resin, phenol resin, unsaturated polyester resin , Polyimide resin, urethane resin, urea resin and the like.

  These binders may be used alone or in combination. In particular, when using hydrolyzable silanes having both a polymerizable functional group and a functional group capable of forming a covalent bond with a silica particle in the same molecule listed in (2), or listed in (5) In the case of using an organic polymer having a polymerizable functional group in the terminal or main chain, the use of the polymerizable monomer listed in (6) is effective in improving mechanical strength. The kind of the polymerizable monomer is appropriately selected according to the form and speed of the reaction. In this case, it is effective to add a polymerization initiator as an additive. As the polymerization initiator, a known one such as a thermal radical generator, a photo radical generator, a thermal acid generator, or a photo acid generator can be selected according to the reaction mode of the above polymerizable functional group or polymerizable monomer. it can. Specific examples of the heat / photo radical generator include Irgacure (registered trademark) and Darocur (registered trademark) acetophenone-based, benzophenone-based, phosphine oxide-based, and titanocene-based commercially available from Ciba Specialty Chemicals Co., Ltd. Each polymerization initiator, a thioxanthone polymerization initiator, a diazo polymerization initiator, an o-acyloxime polymerization initiator, and the like can be mentioned. Among these, polymerization initiators having an amino group and / or a morpholino group in the molecule such as Irgacure (registered trademark) 907, Irgacure (registered trademark) 369, and Irgacure (registered trademark) 379 are particularly preferable. Specific examples of the heat / photoacid generator include Sun Aid (trademark) SI series marketed by Sanshin Chemical Industry Co., Ltd., WPI series, WPAG series, Sigma marketed by Wako Pure Chemical Industries, Ltd. Examples thereof include sulfonium-based, iodonium-based, and diazomethane-based polymerization initiators represented by the PAGs series commercially available from Aldrich Japan.

  The hydrolyzable silanes represented by (1) and (2) can be used in the form of a monomer, but it is preferable to perform partial hydrolysis / dehydration condensation. Partial hydrolysis / dehydration condensation reaction is performed by reacting hydrolyzable silane with water, but as catalysts, acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, boric acid, formic acid, acetic acid; ammonia, trialkylamine Alkalis such as sodium hydroxide, potassium hydroxide, choline and tetraalkylammonium hydroxide; tin compounds such as dibutyltin dilaurate may be used. In this case, partial hydrolysis / dehydration condensation of hydrolyzable silanes may be performed in advance and then mixed with silica particles, or hydrolysis / dehydration condensation reaction may be performed in the presence of silica particles.

  Among the above binders, in particular, hydrolyzable silanes having both a polymerizable functional group and a functional group capable of forming a covalent bond with silica particles in the same molecule represented by (2), or these parts Hydrolysates and dehydrated condensates are preferred. The reason is that silica is easily dispersed uniformly in the antireflection layer, so that it is possible to easily achieve a reduction in surface roughness and presence of silica particles in the vicinity of the surface.

  The binder may be added to the dispersion containing silica particles in advance and then applied to the transfer material substrate, or the binder or solution containing the binder is applied to the transfer material substrate in advance and then the silica particles are included. A dispersion may be applied. In this case, after applying the dispersion containing silica particles, the viscosity of the binder and the type of silica dispersion medium are adjusted so that the binder component penetrates part or all of the silica particle layer, or the heat treatment temperature after application. The mechanical strength of the antireflection layer is improved by setting the time and time, or by pressing. Or conversely, after applying a dispersion containing silica particles to the substrate in advance, a binder or a solution containing the binder may be applied. In this case as well, after the binder is applied, the viscosity of the binder and the type of solvent are adjusted so that the binder component penetrates part or all of the silica particle layer, and the heat treatment temperature and time after application are set. It is preferable to perform pressing.

  Even if the silica particle dispersion contains a binder, it is possible to apply a binder separately. For example, after applying a silica particle dispersion containing hydrolyzable silanes, a (meth) acrylic UV curable resin can be further applied.

  The low refractive index layer contains various additives such as an antistatic agent, an ultraviolet absorber, an infrared absorber, a leveling agent, a dye, a metal salt, a surfactant, and a release agent within the range not impairing the gist of the present invention. It is also possible to make it.

  The method of forming the antireflection layer 43c by a coating method is not limited. When the antireflection layer 43c is coated on the substrate of the transfer material using the coating composition, the shape, content, concentration of the coating liquid, binder and addition of the silica particles It can be formed by appropriately changing the kind of the product, the concentration thereof, the coating method, the coating conditions, and the like.

  Application of the coating composition is a known dipping, spin coater, knife coater, bar coater, blade coater, squeeze coater, reverse roll coater, gravure roll coater, slide coater, curtain coater, spray coater, die coater, cap coater, etc. It can be implemented using a method. Of these, knife coaters, bar coaters, blade coaters, squeeze coaters, reverse roll coaters, gravure roll coaters, slide coaters, curtain coaters, spray coaters, die coaters and cap coaters that can be continuously applied are preferably used.

  After applying the dispersion containing the silica particles and the solution containing the binder, it is effective to heat the dispersion medium to volatilize or to condense and crosslink the silica particles and the binder component. The heating temperature and time are determined by the heat resistance of the substrate of the transfer material. For example, when a glass substrate is used as the base material of the transfer material, heating at 500 ° C. or higher can be performed. When a plastic substrate is used as the base material of the transfer material, the heating temperature is selected from 50 ° C. to 200 ° C., and the heating time is selected from 1 second to 1 hour, preferably from 80 ° C. to 150 ° C., from 10 seconds to 3 seconds. The range of minutes. Moreover, when the said binder has radiation curability, an ultraviolet-ray, an electron beam, etc. are irradiated by a well-known method.

  Providing a high refractive index layer directly below the low refractive index layer is effective because the antireflection effect can be further enhanced. Examples of the high refractive index layer include those obtained by dispersing known inorganic fine particles such as oxides or composite oxides of metals such as titanium, zirconium, zinc, cerium, tantalum, yttrium, hafnium, aluminum, and magnesium in a binder. Used. Of the above metal oxides, zirconium oxide having both a high refractive index and light resistance is particularly preferable. As the binder, those listed in the above (1) to (7) can be used as binders for the low refractive index layer. Among them, the polymerizable functional group and silica in the same molecule described in (2) are preferable. Hydrolyzable silanes having both functional groups capable of forming covalent bonds with particles, those having a polymerizable functional group at the side chain or terminal among the organic polymers described in (5), described in (6) A polymerizable monomer according to (7). As the kind and amount of these binders, known binders can be used depending on the desired refractive index, strength, light resistance, yellowing and the like. The refractive index of the high refractive index layer is preferably set to a value in the range of 1.4 to 2.5 and as close to the square of the refractive index of the low refractive index layer as possible. The thickness of the high refractive index layer is usually set to 0.01 μm to 1 μm.

  In addition, providing an antistatic layer in the antireflection layer 43c is effective because it can prevent dust from adhering to the antireflection layer 43c. As the antistatic layer, a known antistatic agent such as a surfactant or an ionic polymer, or conductive fine particles dispersed in a binder is used. Examples of conductive fine particles include oxide or composite oxide fine particles such as indium, zinc, tin, molybdenum, antimony, and gallium, copper, silver, nickel, low-melting-point alloy (solder, etc.) metal fine particles, and metal-coated polymers. Known materials such as fine particles, various kinds of carbon black, conductive polymer particles such as polypyrrole and polyaniline, metal fibers, and carbon fibers are used. Among these, ITO (tin-containing indium oxide) particles and ATO (tin-containing antimony oxide) particles are particularly preferable because they can exhibit high transparency and conductivity. The thickness of the antistatic layer is usually set to 0.01 μm to 1 μm. As the binder, those listed in the above (1) to (7) can be used as binders for the low refractive index layer. Among them, the polymerizable functional group and silica in the same molecule described in (2) are preferable. Hydrolyzable silanes having both functional groups capable of forming covalent bonds with particles, those having a polymerizable functional group at the side chain or terminal among the organic polymers described in (5), described in (6) A polymerizable monomer according to (7).

  A coating layer may be provided in order to impart slipperiness or antifouling property to the surface of the antireflection layer. The coating layer is, for example, a fluororesin, a moisture curable silicone resin, a thermosetting silicone resin, silicon dioxide, a (meth) acrylic resin, a (meth) acrylic UV curable resin, an epoxy resin, a phenoxy resin, a novolac resin, It is made of any known material such as silicone acrylate resin, melamine resin, phenol resin, unsaturated polyester resin, polyimide resin, urethane resin, urea resin. The film thickness of the coating layer is usually 50 nm or less, preferably 30 nm or less, more preferably 15 nm or less, and most preferably 6 nm or less. The coating layer may be composed of a single layer or a plurality of layers. Among these, a fluororesin, a moisture curable silicone resin, and a thermosetting silicone resin are preferable in order to exhibit an antifouling effect.

  When producing the antireflection diffusion plate of the present invention, an antireflection layer and a hard coat layer are formed on a base material to produce a transfer material, and the layer laminated surface of the transfer material is transferred to one main surface of the diffusion plate body . That is, the structure of the transfer material is substrate (support) / antireflection layer / hard coat layer / adhesive layer.

  For the base material (support), a plastic film can be preferably used. For example, a cellulose acetate film such as a (meth) acrylic resin sheet, a polyethylene film, a polypropylene film, triacetyl cellulose, cellulose acetate propionate; Polyester films such as terephthalate and polyethylene naphthalate; plastics such as polycarbonate film, norbornene film, polyarylate film and polysulfone film, cellulose triacetate film, cellulose acetate propionate film, polycarbonate film, stretched polyethylene terephthalate film A film can be used.

  In this transfer material, an antireflection layer is provided on these substrates by a method such as coating using the coating composition for the antireflection layer 43c described above, and then a coating composition for the hard coat layer 43b is formed. It is produced by providing a hard coat layer by a method such as coating and further providing an adhesive layer.

  The adhesive layer is not limited to the type of adhesive, and has a function of adhering the diffusion plate main body 43a and the transfer material, such as a known adhesive, an adhesive sheet, a thermoplastic resin, a thermosetting resin, and a radiation curable resin. Any material can be used as long as it has the following. Note that the adhesive layer is preferably optically transparent in the visible light region. The thickness of the adhesive layer is usually in the range of 0.3 μm to 20 μm, preferably 0.5 μm, considering the adhesive strength, the function of the hard coat layer, transparency, etc., depending on the surface state of the adherend. A range of ˜3 μm is preferred. A thickness that does not impair the function of the hard coat layer 43b is preferable, for example, about 0.1 μm.

  The transfer material may be provided with an antistatic layer or the like between the base material and the antireflection layer 43c, particularly between the antireflection layer 43c and the diffuser plate body 43a, as necessary. In addition, you may form the layer containing a pigment | dye, a ultraviolet absorber, etc. in the range which does not impair the meaning of this invention.

  In the method of transferring the transfer material to the diffusion plate body 43a, the adhesive layer of the transfer material is attached to the diffusion plate body 43a so that the layer lamination surface of the transfer material and the diffusion plate body 43a face each other. The antireflection layer and the hard coat layer are transferred onto the diffusing plate main body 43a by peeling and removing.

  In order to improve the peelability between the substrate and the antireflection layer, a peelable layer may be provided between them. Although it does not limit as a material of a peeling layer, Well-known things, such as a fluororesin, a silicone resin, a (meth) acrylic resin, a melamine resin, can be used.

  As a method for attaching the transfer material to the diffusion plate main body 43a, a known method such as a heat laminating method or an ultraviolet irradiation method can be used.

  A more industrially preferable method is that when the transfer material obtained in the separate process is attached to the diffusion plate main body 43a in the subsequent stage of the extrusion process of the diffusion plate main body 43a, the diffusion plate main body 43a is cooled to such an extent that it is not deformed by pressure. In this state, the transfer material is pressure-bonded to the diffusion plate main body 43a with a heating roll.

  Such an antireflection diffuser of the present invention suppresses white blurring, improves light transmission, and has excellent scratch resistance and pencil hardness. Therefore, the diffusion for a transmissive screen used in a rear projection type projection television is used. It can be applied not only to the plate but also to various display members.

  Next, examples performed for clarifying the effects of the present invention will be described. The scope of the present invention is not limited to the contents of the following examples.

(1) Evaluation of surface roughness (Ra) using scanning probe microscope Apparatus: NanoScope (registered trademark) IIIa (manufactured by Digital Instruments, USA)
Cantilever: NCH-10T silicon single crystal probe (manufactured by NanoWorld, Switzerland)
・ Mode: Tapping ・ Scan size: 1.0 μm
・ Scan rate: 1.0 Hz
Tip velocity: 2.0 μm / s
・ Set point: 1.5
・ Integral gain: 0.46
・ Proportional gain: 1.3
Image processing: Flatten processing was performed with Flatten order = 0, and vertical correction was performed.

(2) Measurement of minimum reflectance Using an FE-3000 reflection spectrometer (manufactured by Otsuka Electronics Co., Ltd.), a reflection spectrum in a wavelength range of 250 nm to 800 nm was measured. The minimum reflectance in the wavelength range was determined as the minimum reflectance.

(3) Scratch resistance test A surface property tester (manufactured by Imoto Seisakusho Co., Ltd.) was used. A steel wool (Bonster (registered trademark) # 0000, manufactured by Nippon Steel Wool Co., Ltd.) is attached to one end of a stainless steel column with a diameter of 15 mm. It was observed visually.

(4) Pencil hardness Based on JIS K5400 description, it carried out under 1 kg load.

Example 1
(Manufacture of transfer material)
A beaded silica string having an average diameter of about 12 nm and an average length of about 100 nm (Snowtex (registered trademark) OUP, manufactured by Nissan Chemical Industries, Ltd., silica solid content concentration of 15.5% by mass) 89.1 g, average diameter Is a spherical silica sol having a diameter of about 10 nm (Snowtex (registered trademark) OS, manufactured by Nissan Chemical Industries, Ltd., silica solid concentration 20.3 mass%) 68.1 g and ethanol 75.7 g are mixed at room temperature, 17.1 g of roxypropyltrimethoxysilane (Syra Ace S710, manufactured by Chisso Corporation) was added and stirred at 25 ° C. for 4 hours for reaction. A mixed solution consisting of 2.0 g of Irgacure (registered trademark) 369 (manufactured by Ciba Specialty Chemicals Co., Ltd.) and 252 g of ethanol is added to 200 g of this reaction solution, and the mixture is stirred and mixed at room temperature for 5 minutes to obtain a solid concentration of 7. A 5% by weight solution was obtained. This solution was diluted with isopropyl alcohol to a solid content concentration of 3.4% by mass to obtain a coating composition A for an antireflection layer.

  Next, 92.9 g of tin-containing indium oxide fine particle dispersion (ELCOM V-2506, manufactured by Catalyst Kasei Kogyo Co., Ltd., solid content concentration 20.5% by mass), zinc oxide fine particle dispersion (ZNAP15WT% -G0, CI Chemical Industry Co., Ltd.) 125.3 g (solid content concentration 15.0% by mass) were mixed, and a mixed solvent consisting of 304.2 g of isopropyl alcohol, 33.8 g of ethylene glycol monobutyl ether and 23.9 g of water was further added, and acrylic ultraviolet rays were further added. A mixed solution consisting of 9.9 g of a cured resin (Sunrad (registered trademark) RC-600, manufactured by Sanyo Chemical Industries, Ltd., solid content: 100% by mass) and 9.9 g of methyl ethyl ketone was added and stirred at room temperature to obtain a solid content of 8 A 0.0% by weight solution was obtained. This solution was diluted with a mixed solvent composed of isopropyl alcohol and ethylene glycol monobutyl ether (mass ratio 9: 1) to a solid content of 6.0% by mass to obtain a coating composition B for an antistatic layer.

  A transfer material C having a layer structure of polyethylene terephthalate (PET) film / release layer / antireflection layer / antistatic layer / hard coat layer / adhesive layer was produced by the method described below.

On a biaxially stretched PET film having a thickness of 50 μm, a 50% by mass methyl ethyl ketone solution of an acrylic UV curable resin (Sunrad (trademark) RC-600, manufactured by Sanyo Chemical Industries, Ltd., solid content: 100% by mass) is coated with a bar coater (USA). RDSpecialities, Inc. # 7 rod is applied), using an UV curing device (LC-6B manufactured by Fusion UV Systems Japan Co., Ltd.) with an output of 180 W, a conveyor speed of 12 m / min, and a light source distance of 53 mm A release layer was formed by performing ultraviolet irradiation (integrated light amount 250 mJ / cm ² ) three times.

The coating composition A for the antireflection layer is coated on the release layer with a bar coater (US RD Specialities,
Inc. # 4 rod) and dried by heating in a circulating hot air dryer at 120 ° C. for 2 minutes, followed by an ultraviolet curing device (LC-6B type manufactured by Fusion UV Systems Japan Co., Ltd.) The antireflection layer was formed by performing ultraviolet irradiation (integrated light amount 250 mJ / cm ² ) three times with an output of 180 W, a conveyor speed of 12 m / min, and a light source distance of 53 mm.

The antistatic layer coating composition B was applied onto the antireflection layer with a bar coater (equipped with a # 4 rod manufactured by RD Specialities, Inc., USA) and an ultraviolet curing device (LC-manufactured by Fusion UV Systems Japan Co., Ltd.). The antistatic layer was formed by performing ultraviolet irradiation (integrated light amount 250 mJ / cm ² ) three times with an output of 180 W, a conveyor speed of 12 m / min, and a light source distance of 53 mm.

  On the antistatic layer, a urethane acrylate hard coat layer having a thickness of 5 μm and a thermoplastic urethane adhesive layer having a thickness of 2 μm were successively formed to prepare a transfer material C.

(Manufacture of antireflection diffuser)
The following compounds were charged into a reaction vessel equipped with a stirrer, a reflux condenser, and a nitrogen gas inlet.
Methyl methacrylate 60 parts by weight Butyl acrylate 15 parts by weight Styrene 25 parts by weight Allyl methacrylate 2.0 parts by weight t-Dodecyl mercaptan 0.3 parts by weight Azobisisobutyronitrile 0.5 parts by weight Polyvinyl alcohol 3.0 parts by weight Water 200 Parts by mass

  After substituting the inside of the reaction vessel with nitrogen, the mixture was heated to 70 ° C. with stirring to proceed the polymerization. After 4 hours, the temperature was raised to 90 ° C. and held at 90 ° C. for 1 hour to complete the polymerization. After the polymerization, dehydration, washing with water, drying and classification were performed to obtain beads having an average particle size of 30 microns.

  Delmeth (registered trademark) 70H (manufactured by Asahi Kasei Chemicals) 100 parts by weight of methyl methacrylate resin, 2 parts by weight of the beads and Tospearl (registered trademark, spherical silicone particles, average particle size 5 microns, manufactured by GE Toshiba Silicones) 0 A mixture composed of 0.04 parts by mass was extruded using an extruder under a resin temperature of 250 ° C., and the molten resin from the die was passed between rolls and cooled to obtain a diffusion plate body having a thickness of 2 mm.

  The transfer material C is aligned on the obtained diffusion plate body so that the adhesive layer and the diffusion plate body are in contact with each other, and a roller temperature 230 is used using a laminator (MA II-550 type, manufactured by Taisei Laminator Co., Ltd.). Transfer was performed at a temperature of 1 ° C., a roller pressure of 1 kg, and a feed rate of 0.8 cm / sec. After cooling to room temperature, the PET film and the release layer are peeled and removed, whereby an anti-reflection diffusion plate laminated with an adhesive layer / hard coat layer / anti-static layer / anti-reflection layer on one side of the diffusion plate body (Example) 1) was obtained. The obtained antireflection diffuser had a surface roughness (Ra) as small as 0.5 nm and a minimum reflectance as low as 0.82%, and had good antireflection performance.

  The image of the projector is imaged on the obtained anti-reflection diffuser plate, and the sharpness and white blur of the image are compared by visual observation, and evaluated in four stages, excellent (◎), good (○), acceptable (△ ), Impossibility (×). Further, the steel wool strength and pencil hardness of the antireflection diffuser surface were measured. The evaluation results are shown in Table 1 below. As can be seen from Table 1, the antireflection diffuser plate of Example 1 was excellent in optical performance and mechanical strength.

(Example 2)
An ultraviolet curable resin composition is applied to the molding surface of a mold having the opposite shape of a lens, a 0.125 mm thick polyester film (PET) is laminated as a base material, and ultraviolet rays are irradiated through the base material. Thus, a lenticular lens sheet having a predetermined shape was produced by curing the resin and simultaneously polymerizing and bonding a lens made of the resin-cured molding to a base material.

  Further, after laminating an uncured film-like ultraviolet curable resin on a flat surface opposite to the lens surface, the resin in the portion condensed by each lens group is irradiated with ultraviolet rays vertically through the lens surface. Is made to be non-tacky by curing, and then using a transfer paper provided with a black ink layer only on the uncured part of the adhesive resin, the black colorant only on the uncured part A stripe-shaped light shielding layer was formed by adhering. The treated surface of the antireflection diffuser plate provided with the antireflection layer / antistatic layer / hard coat layer obtained in Example 1 is provided on the surface of the lenticular lens sheet on which the light shielding layer is formed via an adhesive film for optical use. A laminated lenticular plate (Example 2) was prepared so as to be the outermost surface on the observation side.

  On the other hand, a 1.85 mm thick Fresnel lens sheet made of acrylic resin of a predetermined shape is manufactured, and a 60-inch transmissive screen combining the Fresnel lens sheet and the lenticular plate is mounted on a rear projection type projection television apparatus. The images were fixed, and the sharpness and white blur of the image were compared by visual observation, and evaluated in four stages, and expressed as excellent (（), good (◯), acceptable (Δ), and impossible (×). Further, the steel wool strength and pencil hardness of the surface of the antireflection diffuser were measured. The evaluation results are shown in Table 2 below. As can be seen from Table 2, the lenticular plate of Example 2 was excellent in optical performance and mechanical strength.

(Example 3)
In Example 1, the transfer material C was produced by continuously applying with a micro gravure coater instead of a bar coater, and was formed into a roll.

  The adhesive layer of the transfer material C is pressure-bonded to the diffusion plate body by a heating roll in a state where the diffusion plate body is cooled to the extent that it is not deformed by pressurization downstream of the continuous production line. Anti-reflection diffuser laminated with adhesive layer / hard coat layer / anti-static layer / anti-reflective layer on one side of diffuser plate by peeling and removing PET film and release layer after bonding to main body Example 3 was obtained. The obtained antireflection diffuser had a surface roughness (Ra) as small as 0.5 nm and a minimum reflectance as low as 0.82%, and had good antireflection performance.

  The image of the projector is imaged on the obtained anti-reflection diffuser plate, and the sharpness and white blur of the image are compared by visual observation, and evaluated in four stages, excellent (◎), good (○), acceptable (△ ), Impossibility (×). Further, the steel wool strength and pencil hardness of the surface of the antireflection diffuser were measured. The evaluation results are shown in Table 3 below. As can be seen from Table 3, the antireflection diffuser of Example 3 was excellent in optical performance and mechanical strength.

(Comparative example)
In Example 1, a polyester film (PET, thickness 0.125 mm) provided with an antireflection layer, an antistatic layer, and a hard coat layer was prepared without using the transfer material C, and the side opposite to the lamination side was the diffusion plate body. The PET film was laminated on the diffusion plate body via an adhesive film for optical use so as to be in contact with each other, thereby producing a diffusion plate (comparative example). The obtained diffusion plate was examined for optical performance and mechanical strength in the same manner as in Example 1. The evaluation results are shown in Table 4 below. As can be seen from Table 4, the diffusion plate of the comparative example was inferior in sharpness and mechanical strength. This is presumably because a PET film is used.

  The present invention can be applied to an antireflection diffusion plate for a transmissive screen used in a rear projection type projection television or the like.

  The present invention is not limited to the embodiment described above, and can be implemented with various modifications. For example, the dimensions, materials, and the like in the above-described embodiment are illustrative, and can be changed as appropriate. In addition, various modifications can be made without departing from the scope of the present invention.

It is a figure which shows schematic structure of the rear projection type projection television which has a transmission type screen provided with the reflection preventing diffusion plate which concerns on one embodiment of this invention. It is sectional drawing which shows the structure of the reflection preventing diffusion plate of the transmissive screen shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source 2 Video projection apparatus 3 Projection lens 4 Transmission type screen 41 Fresnel lens sheet 42 Lenticular lens sheet 43 Diffusion plate 43a Diffusion plate body 43b Hard coat layer 43c Antireflection layer

Claims (6)

  An antireflection diffusion plate comprising: a diffusion plate body; a hard coat layer formed on one main surface of the diffusion plate body; and an antireflection layer formed on the hard coat layer. .   2. The anti-reflection diffusion plate according to claim 1, wherein the diffusion plate body has diffusion particles dispersed therein.   The antireflection diffusion plate according to claim 1, further comprising an antistatic layer between the antireflection layer and the diffusion plate body.   The antireflection diffuser plate according to any one of claims 1 to 3, a lenticular lens member disposed on a diffusion plate main body side of the antireflection diffuser plate, and disposed so as to face the lenticular lens member. A rear projection display screen, comprising: a Fresnel lens member.   Forming a transfer material by forming an antireflection layer and a hard coat layer on a substrate, and transferring the layer laminated surface of the transfer material to one main surface of the diffusion plate body. A method for producing an antireflection diffuser plate.   6. The method of manufacturing an antireflection diffuser plate according to claim 5, wherein the step of producing the transfer material includes a step of forming an antistatic layer between the base material and the hard coat layer.

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