JP2014038171A - Anisotropic light-diffusing laminate and projector screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anisotropic light-diffusing laminate capable of improving a horizontal viewing angle while maintaining visibility (such as brightness and sharpness) of an image projected by a projector.SOLUTION: An anisotropic light-diffusing layer formed of a continuous phase containing a polycarbonate resin and a long dispersion phase containing a polypropylene resin is laminated with an isotropic light-diffusing layer having a haze value of 65 to 80% to constitute an anisotropic light-diffusing sheet to be included in a screen for displaying an image projected by a projector. The long dispersion phase of the anisotropic light-diffusing layer has an average aspect ratio of 100 or more; and the major axis direction of the long dispersion phase is oriented in a given direction in the anisotropic light-diffusing layer.

Description

  The present invention relates to an anisotropic light diffusion laminate included in a screen for displaying an image projected from a projector, and a projector screen including the laminate.

  A projector (projector or projection display device) is an apparatus for displaying an enlarged image on a screen and displaying an image of a cathode ray tube or a liquid crystal on the screen in addition to an overhead projector (OHP) or a slide projector. It is used as a projector that displays images. Projectors are usually used for the purpose of making a large number of people visually recognize, so the required characteristics of the screen can be seen from various angles in addition to the brightness and image clarity due to screen gain (reflection brightness). Therefore, improvement in reflection characteristics (viewing angle characteristics) is also required. As a method for improving the viewing angle characteristics, a method using a diffusion film is known. However, since the reflection luminance and the reflection characteristics are in a trade-off relationship, when the viewing angle characteristics are improved, the reflection luminance is to some extent. I have to sacrifice. On the other hand, although it is necessary to eliminate the difference in visibility due to the difference in the viewing position of the viewer, the viewing angle characteristics in the direction of gravity (vertical direction) are much required because the height of the line of sight of each viewer is substantially constant. Not. Therefore, an attempt has been made to use an anisotropic light diffusion sheet that can diffuse more in the horizontal direction than in the vertical direction.

  In JP-A-5-113606 (Patent Document 1), in a transparent matrix, substances having an anisotropic shape and a refractive index different from that of the transparent matrix are arranged in parallel with each other in an orderly manner. A reflective screen is disclosed that is composed of a homogeneously dispersed anisotropic light scattering material. In this document, various thermoplastic resins are exemplified as the transparent matrix and the anisotropic light scattering material, and after extruding a resin composition obtained by kneading these resins, it is stretched in a uniaxial direction. The production of a reflective screen is described. In the example, a film is produced in which elliptical polystyrene particles (major axis about 20 μm, minor axis about 1 μm) are dispersed in a transparent matrix of low density polyethylene.

  However, since the anisotropic light diffusion sheet obtained by stretching is small in anisotropy, the viewing angle cannot be sufficiently expanded. In order to enlarge the viewing angle, increasing the draw ratio and increasing the anisotropy of the dispersed phase (island phase) also increases the gap between the dispersed phases, and through light (light omission) with a scattering angle of 0 °. Occurs and the viewing angle characteristics cannot be improved. On the other hand, in order to form a sea-island structure, it is difficult to make the proportion of the island portion larger than the proportion of the sea portion. Therefore, the sea-island structure is inevitably a structure in which the island part is somewhat sparse, and in the anisotropic sheet by stretching, the gap between the island parts is further enlarged, so that the generation of through light is avoided. This is a problem that cannot be solved, and is particularly noticeable in projector screens that require high anisotropy.

  International Publication No. WO2008 / 120709 (Patent Document 2) discloses a directivity including a directional diffusion element including a transparent resin matrix and inorganic needle fillers that are oriented and dispersed in a certain direction within the transparent resin matrix. There is disclosed a reflective screen for a projector having a diffusive diffusion layer and having a horizontal viewing angle of 1.2 times or more of a vertical viewing angle. In this document, the aspect ratio of the inorganic needle filler is described as 2 to 1000 (particularly 10 to 300). In the examples, aluminum borate whiskers (major axis 10 to 30 μm, minor axis 0.5 to 1.0 μm). ) Is used. Furthermore, this document describes combining the directional diffusing element with an isotropic diffusing element in which spherical or amorphous fillers are dispersed in a transparent resin matrix.

  However, it is difficult to orient the inorganic needle filler in a certain direction, and it is also difficult to disperse it uniformly, so that uniform anisotropic diffusibility cannot be realized.

  As an anisotropic light diffusing sheet used for a backlight for a liquid crystal display device, Japanese Patent Application Laid-Open No. 2002-98810 (Patent Document 3) discloses a base in which rod-shaped bubbles are directed parallel to the sheet surface and in one direction. An anisotropic diffusion sheet is disclosed in which a material layer and an isotropic diffusion layer in which beads are dispersed in a binder are laminated. According to this means, according to this means, it is possible to improve the anisotropy of the light output characteristics of the backlight unit by exerting an anisotropic diffusion action on the base material layer, and further the isotropic diffusion action by the isotropic diffusion layer. As a result, the base layer can be designed in the size and density of the rod-shaped bubbles considering only anisotropic diffusion, and the light output characteristics are anisotropic. It is described that the improving action can be enhanced. Further, it is described that the aspect ratio of the rod-shaped bubbles is 1.5 to 20, preferably 5 to 15. Furthermore, the ratio of bubbles in the base material layer is described as 1 to 80% by volume, preferably 5 to 50% by volume. In the examples, base material layers having a ratio of 24.3% by volume and 36.9% by volume are prepared. ing.

  However, in this sheet, since the dispersed phase is bubbles, the ratio of the bubbles is limited from the viewpoint of sheet shape retention, and the dispersed phase is a gas, so a shape with a high aspect ratio is formed. It is also difficult. Therefore, the viewing angle characteristics cannot be improved with this sheet.

  Japanese Patent Application Laid-Open No. 2010-44320 (Patent Document 4) also discloses a light control film composed of at least a lens layer, an isotropic diffusion layer, and an anisotropic diffusion layer, and isotropic. A light control film is disclosed in which the haze of the diffusion layer is 60% or more, and the lens layer is disposed closer to the light exit surface than the anisotropic diffusion layer. According to this document, the haze of the isotropic diffusion layer is preferably 80% or more (particularly 90% or more) from the viewpoint of more effectively suppressing the improvement of luminance and the expression of a lamp image (lamp image). In the examples described, the light control film comprising an isotropic diffusion layer with a haze of 84-91% was superior in lamp image erasability than the light control film comprising an isotropic diffusion layer with a haze of 67%. Results are shown.

  However, this light control film is intended to suppress the reflection of the backlight type liquid crystal display device, and is not intended to increase the viewing angle. Further, a diffusion sheet used in a backlight type liquid crystal display device does not normally require high anisotropy like a projector screen for viewing a magnified image by a plurality of people.

  When the anisotropic light diffusion layer and the isotropic light diffusion layer are combined, the light diffusion characteristics between the anisotropic light diffusion layer and the isotropic light diffusion layer are in a trade-off relationship. The function of is reduced. Therefore, even if both layers are combined, it is extremely difficult to maintain the anisotropy of light diffusion (particularly the large anisotropy required for the projector screen) while suppressing the generation of through light. Further, it is possible to form a dense concavo-convex structure on the surface structure using a molding die or the like and impart anisotropic diffusion, but it is not so popular because productivity is lowered.

JP-A-5-113606 (Claims, paragraphs [0007] [0016] [0019], Examples) International Publication WO2008 / 120709 (Claims, paragraphs [0035] and [0043], Examples) JP 2002-98810 A (claims, paragraphs [0015] [0026] [0027], Examples) JP 2010-44320 A (Claim 1, paragraph [0120], Example)

  Accordingly, an object of the present invention is to diffuse anisotropic light that can improve the viewing angle in the horizontal direction (perpendicular to the gravitational direction) while maintaining the visibility (brightness, sharpness, etc.) of the image projected from the projector. It is to provide a laminate and a projector screen.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that an anisotropic light diffusion layer having a specific anisotropy formed of a continuous phase containing a polycarbonate resin and an elongated dispersed phase containing a polypropylene resin, and By combining with an isotropic light diffusion layer having a haze of 65 to 80% and using it as a screen diffusion sheet for displaying an image projected from the projector, the visibility of the image projected from the projector (brightness and sharpness) Etc.) and the horizontal viewing angle can be improved, and the present invention has been completed.

  That is, the anisotropic light diffusion laminate of the present invention is an anisotropic light diffusion laminate included in a screen for displaying an image projected from a projector, and includes an anisotropic light diffusion layer and an isotropic light diffusion layer, The anisotropic light diffusion layer is formed of a continuous phase containing a polycarbonate resin and a long dispersion phase containing a polypropylene resin, and the longitudinal direction of the long dispersion phase is oriented in a certain direction of the anisotropic light diffusion layer. And the scattering characteristic F (θ) indicating the relationship between the scattering angle θ and the scattered light intensity F, the scattering characteristic in the longitudinal direction of the elongated dispersed phase is Fx (θ), and the longitudinal direction of the elongated dispersed phase is Where Fy (θ) is the scattering property in the direction perpendicular to the angle, the scattering angle θ is 5 °, 2 ≦ Fy (θ) / Fx (θ) ≦ 20, and the haze of the isotropic light diffusion layer is 65-80. %. The haze may be 70 to 78%. The anisotropic light diffusion layer may have a scattering angle θ = 5 ° and 5 ≦ Fy (θ) / Fx (θ) ≦ 15. The anisotropic light diffusing laminate of the present invention has an angle of 15 ° or less at which the scattering intensity is 1/10 times the 0 ° scattering intensity in the longitudinal (major axis) direction of the elongated dispersed phase, and is long. In a direction perpendicular to the longitudinal (major axis) direction of the scale-like dispersed phase, the angle at which the scattering intensity is ½ times the 0 ° scattering intensity may be 8 ° or more. The anisotropic light diffusion layer and the isotropic light diffusion layer may be integrated through an adhesive layer. The isotropic light diffusion layer may be integrated with the anisotropic light diffusion layer by being formed on the anisotropic light diffusion layer by coating. In the anisotropic light diffusion laminate of the present invention, a transparent layer may be formed on at least one surface of the anisotropic light diffusion layer, and the transparent layer and the isotropic light diffusion layer may be integrated. The polycarbonate resin may be a polycarbonate resin having a number average molecular weight of 15,000 to 25000, and the polypropylene resin may be a metallocene catalyst resin.

  The present invention also includes a projector screen including the anisotropic light diffusion laminate. The projector screen may be a reflective screen and an anisotropic light diffusion layer may be disposed on the surface side.

  In the present invention, an anisotropic light diffusion layer having a specific anisotropy formed of a continuous phase containing a polycarbonate resin and an elongated dispersed phase containing a polypropylene resin, and an isotropic light diffusion layer having a haze of 65 to 80% Since they are combined, it is possible to improve the viewing angle in the horizontal direction while maintaining the visibility (brightness, sharpness, etc.) of the image projected from the projector.

FIG. 1 is a conceptual diagram for explaining anisotropic scattering of an anisotropic light diffusion layer. FIG. 2 is a schematic diagram for explaining a method for measuring light scattering characteristics. FIG. 3 is a graph obtained by measuring the relationship between the scattering angle and the scattering intensity of the anisotropic light diffusion layer obtained in Example 1 in each of the longitudinal direction of the elongated dispersed phase and the direction perpendicular to the longitudinal direction. is there. FIG. 4 is a graph obtained by measuring the relationship between the scattering angle and the scattering intensity of the anisotropic light-diffusing laminate obtained in Example 1 in each of the longitudinal direction of the elongated dispersed phase and the direction perpendicular to the longitudinal direction. It is. FIG. 5 is a graph obtained by measuring the relationship between the scattering angle and the scattering intensity of the anisotropic light-diffusing laminate obtained in Comparative Example 2 in each of the longitudinal direction of the long dispersed phase and the direction perpendicular to the longitudinal direction. It is.

[Anisotropic light diffusion laminate]
An anisotropic light diffusion laminate is an anisotropic light diffusion sheet included in a screen for displaying an image projected from a projector, and includes an anisotropic light diffusion layer and an isotropic light diffusion layer. Furthermore, a transparent layer may be laminated on at least one surface of the anisotropic light diffusion layer.

(Anisotropic light diffusion layer)
The anisotropic light diffusion layer is composed of a continuous phase (matrix phase) containing a polycarbonate resin and a long dispersed phase containing a polypropylene resin, and a phase separation structure in which the long dispersed phase is dispersed in the continuous layer ( Or a sea-island structure).

Polycarbonate resins include aromatic polycarbonates based on bisphenols. Examples of bisphenols include bisphenols such as dihydroxybiphenyl, bis (hydroxyaryl) alkanes such as bisphenol A, bisphenol F, and bisphenol AD, and bis (hydroxyaryl) cycloalkanes such as bis (hydroxyphenyl) cyclohexane, 4 Di (hydroxyphenyl) ethers such as 4,4'-di (hydroxyphenyl) ether, di (hydroxyphenyl) ketones such as 4,4'-di (hydroxyphenyl) ketone, di (hydroxyphenyl) such as bisphenol S And bisphenol fluorenes such as sulfoxides, bis (hydroxyphenyl) sulfones, and 9,9-bis (4-hydroxyphenyl) fluorene. These bisphenols may be C _2-4 alkylene oxide adducts. These bisphenols can be used alone or in combination of two or more.

The polycarbonate resin may be a polyester carbonate obtained by copolymerizing a dicarboxylic acid component (such as an aliphatic, alicyclic or aromatic dicarboxylic acid or an acid halide thereof). These polycarbonate resins can be used alone or in combination of two or more. Preferred polycarbonate resins are resins based on bis (hydroxyphenyl) C _1-6 alkanes, such as bisphenol A type polycarbonate.

  The number average molecular weight of the polycarbonate resin can be selected from a range of about 10,000 to 50000 (for example, 15000 to 30000), for example, 12500 to 30000 (for example, 15000 to 25000), preferably 17000 to 25000 (for example, 18000 to 22000). Degree. If the molecular weight of the polycarbonate resin is too small, the strength of the sheet is lowered, and if the molecular weight is too large, the melt fluidity and the uniform dispersibility of the dispersed phase are liable to be lowered. When the polycarbonate resin and the specific polypropylene resin are combined, a long dispersed phase having a high aspect ratio can be formed without generating voids without using a compatibilizing agent.

  The melt flow rate (MFR) of the polycarbonate resin is, for example, about 3 to 30 g / 10 minutes (for example, 4 to 20 g / 10 minutes) in accordance with ISO 1133 (300 ° C., 1.2 kg load (11.8 N)). Usually, 5 to 30 g / 10 minutes (for example, 5 to 15 g / 10 minutes), preferably 6 to 25 g / 10 minutes (for example, 7 to 20 g / 10 minutes), more preferably 8 to 15 g / minute. It is about 10 minutes (for example, 9 to 12 g / 10 minutes).

  The melting point or glass transition temperature of the polycarbonate resin is, for example, about 130 to 280 ° C, preferably about 140 to 270 ° C, and more preferably about 150 to 260 ° C.

  Such polycarbonate resins are often classified as “medium viscosity products”, “low viscosity products”, and “high flow” grades in product catalogs.

The polypropylene resin forming the long dispersed phase includes polypropylene (homopolymer) and a copolymer of propylene and a copolymerizable monomer. Copolymerizable monomers include olefins (in addition to ethylene, α-C _4-10 olefins such as butene, pentene, heptene, hexene, etc.), (meth) acrylic monomers (for example, (meth) Acrylic acid, (meth) acrylic acid C _1-10 alkyl ester, (meth) acrylic acid hydroxyalkyl ester, (meth) acrylic acid glycidyl ester, etc.), fatty acid vinyl esters (vinyl acetate, etc.), dienes and the like. . These copolymerizable monomers can be used alone or in combination of two or more. Of these copolymerizable monomers, α-olefins (ethylene, butene, etc.) are often used.

  In the propylene-based copolymer, the propylene content is often 80 mol% or more (for example, 80 to 100 mol%), preferably 85 mol% or more, and more preferably 90 mol% or more. The propylene-based copolymer may be a block copolymer or the like, but is usually a random copolymer in many cases.

  Preferred polypropylene resins are polypropylene homopolymer, propylene-ethylene copolymer, propylene-butene copolymer, propylene-ethylene-butene copolymer and the like. As a polypropylene-type polymer, a polypropylene homopolymer and a propylene-ethylene copolymer are often used.

  The polypropylene resin may be a polymer using a Ziegler catalyst or the like, but is preferably a metallocene catalyst resin using a metallocene catalyst. The metallocene catalyst-based resin has a feature that the molecular weight distribution is narrow and there are few low molecular weight components and low crystal components. For this reason, the polypropylene resin phase (long dispersion phase) can be uniformly dispersed in the matrix phase of the polycarbonate resin without using a compatibilizing agent.

In gel permeation chromatography (GPC), the molecular weight distribution of the polypropylene resin is, for example, weight average molecular weight Mw / number average molecular weight Mn = 1 to 2.5 (for example, 1.2 to 2.3), preferably 1. It is about 3 to 2 (for example, 1.5 to 1.8), and usually about 1.3 to 2.5 (for example, 1.5 to 2.0). The weight average molecular weight Mw of the polypropylene resin is, for example, 1 × 10 ^{4 to} 100 × 10 ⁴ , preferably 2 × 10 ⁴ to 75 × 10 ⁴ (for example, 3 × 10 ⁴ to 50 × 10 ⁴ ), and more preferably. It may be about 3 × 10 ⁴ to 30 × 10 ⁴ . In GPC, the content of a low molecular weight component having a molecular weight of 10,000 or less is, for example, 1% by volume or less, preferably 0.5% by volume or less, and more preferably 0.3% by volume or less. The molecular weight and molecular weight distribution by GPC can be measured at a temperature of 135 ° C. using an apparatus: Waters Alliance GPCV-2000, a column: PL 20 μm MIXED-A, a detector: RI, and a solvent: o-dichlorobenzene. The molecular weight and molecular weight distribution are values in terms of polypropylene calibrated by a general calibration curve method using monodisperse polystyrene as a reference substance.

  The MFR of the polypropylene resin is, for example, 3 to 20 g / 10 minutes, preferably 4 to 15 g / 10 minutes, more preferably in accordance with JIS K7210 (230 ° C., 2.16 kg load (21.2 N)). Is about 5-10 g / 10 minutes.

  The polypropylene resin may be crystalline, and the crystallinity of the crystalline polypropylene resin is, for example, about 10 to 80%, preferably about 20 to 70%, and more preferably about 30 to 60%. Also good. The melting point (melting peak temperature in the differential scanning calorimeter DSC) of the polypropylene resin is, for example, about 100 to 140 ° C., preferably 110 to 135 ° C., more preferably about 115 to 130 ° C. (for example, 120 to 130 ° C.). is there. The difference in melting point or glass transition temperature between the polypropylene resin and the polycarbonate resin constituting the continuous phase may be, for example, about 10 to 200 ° C, preferably about 30 to 150 ° C, and more preferably about 50 to 120 ° C.

  Furthermore, the ratio of the MFR of the polycarbonate resin and the MFR of the polypropylene resin is the former / the latter = 0.8 / 1 to 2.5 / 1 (for example, 0.9 / 1 to 2.3 / 1), Preferably, it may be about 1/1 to 2/1, more preferably about 1.2 / 1 to 1.7 / 1.

  In order to impart light diffusibility, the continuous phase and the elongated dispersed phase are composed of components having different refractive indexes. The difference in refractive index between the polycarbonate resin and the polypropylene resin is, for example, 0.001 or more (for example, about 0.001 to 0.3), preferably about 0.01 to 0.3, and more preferably 0.01. About 0.1.

  As the polypropylene resin, a copolymer (such as a propylene-ethylene random copolymer) or a metallocene resin using a metallocene catalyst, particularly a metallocene copolymer is preferable.

  When such a polypropylene resin is combined with the polycarbonate resin as described above, a dispersed phase (such as a dispersed phase having a predetermined aspect ratio) can be formed without generating voids even if substantially free of a compatibilizer. Can be formed.

  In the anisotropic light diffusing layer, the ratio of the continuous phase (particularly polycarbonate resin) and the long dispersed phase (particularly polypropylene resin) depends on the type of resin, melt viscosity, light diffusibility, etc. / Latter (weight ratio) = 99/1 to 30/70 (for example, 95/5 to 40/60) or so, for example, 99/1 to 50/50 (for example, 95/5 to 50 / 50), preferably 99/1 to 75/25 (for example, 95/5 to 70/30), more preferably about 95/5 to 60/40, particularly about 90/10 to 75/25. Also good.

  Combining the polycarbonate resin and the polypropylene resin not only has practical thermal stability, but also easily disperses the dispersed phase at the orientation treatment temperature such as uniaxial stretching temperature, making the transmitted light and reflected light anisotropic. A sheet that diffuses into the surface is obtained. Moreover, the aspect ratio of the elongated dispersed phase can be controlled by an orientation treatment such as draw ratio or uniaxial stretching in the extrusion molding process, and a elongated dispersed phase having a large aspect ratio can be easily formed. Furthermore, since the continuous layer is made of a polycarbonate resin, heat resistance and blocking resistance can be improved.

  The anisotropic light diffusion layer may contain a compatibilizing agent as necessary. By using a compatibilizing agent, the miscibility and affinity between the continuous phase and the elongated dispersed phase can be increased, and defects (such as voids) can be prevented from being generated even when the sheet is oriented. A decrease in transparency of the sheet can be prevented. Furthermore, the adhesiveness between the continuous phase and the elongated dispersed phase can be improved, and even if the sheet is uniaxially stretched, adhesion of the elongated dispersed phase to the stretching apparatus can be reduced.

  As the compatibilizing agent, for example, the compatibilizing agent described in International Publication No. WO2009 / 016975 can be used. The use amount of the compatibilizer is, for example, in the range of 0.1 to 20% by weight, preferably 0.5 to 15% by weight, more preferably about 1 to 10% by weight, based on the total amount of the polycarbonate resin and the polypropylene resin. You can choose from. As described above, in the present invention, the dispersed phase can be uniformly dispersed by combining the specific polycarbonate resin and the specific polypropylene resin, even if the compatibilizer is not included. Further, even if an orientation treatment such as uniaxial stretching is performed, there is no void and an anisotropic light diffusion layer having a high transmittance can be formed.

  In the preferred anisotropic light diffusion layer, the ratio of the continuous phase, the elongated dispersed phase, and the compatibilizing agent is, for example, as follows.

(1) Continuous phase / elongated dispersed phase (weight ratio) = about 99/1 to 50/50, preferably about 97/3 to 60/40, more preferably about 95/5 to 70/30, especially 90 / 10˜80 / 20 (2) Long dispersion phase / Compatibilizer (weight ratio) = 100 / 0˜50 / 50, preferably 99 / 1˜70 / 30, more preferably 98/2 About 80/20.

  In addition, in this invention, even if it does not contain the compatibilizing agent by combining the said polycarbonate resin and the said polypropylene resin, a long disperse phase can be disperse | distributed uniformly.

  If each component is used at such a ratio, the dispersed phase can be dispersed evenly by directly melting and kneading the pellets of each component without compounding each component in advance, and by an orientation treatment such as uniaxial stretching. Generation of voids can be prevented, and a light diffusion layer having high transmittance and anisotropy can be obtained.

  More specifically, for example, using a resin composition containing a polycarbonate resin as a continuous phase and a polypropylene resin as a dispersed phase in the above-described ratio makes it easy to compound and only feeds raw materials. The film can be melted while being compounded, and an anisotropic light diffusion layer free from voids can be formed even if uniaxially stretched.

  In addition, as long as it does not adversely affect the light diffusion characteristics, polyethylene-based resin, styrene-based resin, aromatic polyester-based resin (polyalkylene arylate homopolyester such as polyalkylene terephthalate and polyalkylene naphthalate, the inclusion of alkylene arylate units Polymers such as copolyesters and liquid crystalline aromatic polyesters in an amount of 80 mol% or more), polyamide resins (such as aliphatic polyamides such as polyamide 46, polyamide 6 and polyamide 66), inorganic particles such as silica, and the like It may be used as a component of the scale-like dispersed phase.

  Furthermore, the anisotropic light diffusion layer contains conventional additives such as stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), plasticizers, antistatic agents, flame retardants and the like. May be.

  In addition, when an alloy system in which a polycarbonate resin and a polypropylene resin are combined is melt-extruded or compounded, a part of the extrudate gradually accumulates on the die lip (particularly the wall adjacent to the opening of the die lip), This deposit grows into contact with the molten sheet extruded from the die lip and forms a non-uniform sheet. Therefore, it becomes impossible to produce a uniform sheet and film continuously. In such a case, at least one selected from stabilizers (for example, antioxidants and / or ultraviolet absorbers), particularly antioxidants and ultraviolet absorbers (antioxidant alone, ultraviolet absorber alone, antioxidant and When an ultraviolet absorber or the like is contained, the formation and growth of the deposit can be remarkably prevented, and uniform sheets and films can be continuously produced. Incidentally, the antioxidant and / or the ultraviolet absorber), particularly at least the antioxidant, may be contained in the anisotropic light diffusion layer in contact with the die lip, or may be contained in the transparent layer laminated on the anisotropic light diffusion layer. Alternatively, it may be contained in the light diffusion layer and the transparent layer. The anisotropic light diffusion layer usually contains at least one selected from an antioxidant and an ultraviolet absorber in many cases. As the stabilizer, for example, a stabilizer described in International Publication WO2009 / 016975 can be used.

  In the anisotropic light diffusing layer, the long dispersed phase is in the form of a long rod having a ratio of the average length L of the major axis to the average length W of the minor axis (average aspect ratio, L / W) of 10 or more. , Fibrous or yarn). The aspect ratio of the elongated dispersed phase is, for example, about 10 to 1300 (for example, 100 to 1200), preferably about 150 to 1000 (for example, 200 to 900), more preferably about 300 to 800 (particularly about 500 to 750). is there. The larger the aspect ratio of the elongated dispersed phase, the higher the anisotropic light scattering property, but if it is too large, the light passing through is generated and the haze of the isotropic light diffusion layer needs to be increased. In particular, the anisotropic scattering property also decreases. In the anisotropic light diffusing layer that anisotropically diffuses transmitted light and reflected light, the long axis (longitudinal) direction of the elongated dispersed phase is a predetermined direction of the sheet, that is, the X-axis direction (take-off direction or machine direction). Oriented to form an elongated dispersed phase.

  The average length L of the long axis of the long dispersed phase is, for example, about 1 to 2000 μm (for example, 5 to 1500 μm), preferably 10 to 1000 μm, and more preferably about 30 to 500 μm (for example, 50 to 200 μm). Usually, it is about 30 to 200 μm (for example, 100 to 150 μm). The average length W of the short axis of the long dispersed phase is, for example, 0.01 to 10 μm (for example, 0.02 to 5 μm), preferably 0.03 to 5 μm (for example, 0.05 to 3 μm). More preferably, it is about 0.07 to 1 μm (for example, 0.1 to 0.5 μm).

  The orientation coefficient of the elongated dispersed phase as the degree of alignment is, for example, 0.34 or more (about 0.34 to 1), preferably 0.4 to 1 (for example, 0.5 to 1), more preferably 0. It may be about 7 to 1. The higher the orientation coefficient of the long dispersed phase, the higher the anisotropy can be imparted to the scattered light. The orientation coefficient can be calculated based on the following formula.

Orientation coefficient = (3 <cos ² θ> −1) / 2
(In the formula, θ represents an angle between the long axis of the long dispersed phase and the X axis of the film (when the long axis and the X axis are parallel, θ = 0 °), and <cos ² θ> is The average of cos ² θ calculated for each elongated dispersed phase is shown and expressed by the following formula).

<Cos ² θ> = ∫n (θ) · cos ² θ · dθ
(In the formula, n (θ) represents the ratio (weight ratio) of dispersed phase particles having an angle θ in the full length scale dispersed phase).

  The anisotropic light diffusion layer has the directivity of diffused light. That is, having directivity means that there is an angle at which the scattering intensity has a maximum in the direction of strong scattering in anisotropic diffused light. When the diffused light has directivity, when the diffused light intensity F is plotted with respect to the diffusion angle θ in the measurement apparatus of FIG. 2 to be described later, the plot curve shows a range of a specific diffusion angle θ (θ = It has a maximum or a shoulder (in particular, an inflection point such as a maximum) in an angle range other than 0 °.

  FIG. 1 is a conceptual diagram for explaining the anisotropy of light diffusion. As shown in FIG. 1, the anisotropic light diffusion layer (sheet) 1 is composed of a continuous phase 1a composed of a polycarbonate resin and a long dispersed phase 1b dispersed in the continuous phase. The anisotropy of light diffusion is the scattering characteristic (scattering intensity) F (θ) indicating the relationship between the scattering angle θ and the scattered light intensity F, and is in the X-axis direction (longitudinal direction of the long dispersed phase) of the sheet. When the scattering characteristic is Fx (θ) and the scattering characteristic in the Y-axis direction (direction perpendicular to the longitudinal direction of the long dispersed phase) orthogonal to the X-axis direction is Fy (θ), the scattering characteristic Fx (θ) is The scattering characteristic Fy (θ) shows a pattern in which the light intensity gently attenuates as the scattering angle θ becomes a wide angle, whereas the pattern shows a sudden attenuation pattern. In the range of the scattering angle θ = 5 °, the value (anisotropic degree) of Fy (5 °) / Fx (5 °) can be selected from a range of about 1.5 to 25, for example, 2 to 20 (for example, 3-18), preferably 5-15, more preferably about 6-13 (especially 8-12). In the range of the scattering angle θ = 10 °, the value of Fy (10 °) / Fx (10 °) is, for example, about 3 to 30, preferably about 10 to 25, and more preferably about 15 to 20. If the degree of anisotropy is too small, the anisotropic scattering property is lowered, and if it is too large, the light passing through is generated, and the anisotropic scattering property is also lowered due to an increase in the haze of the isotropic light diffusion layer.

  The anisotropic light diffusion layer has a ratio [Fy (0 °) / Fy () of the scattering characteristic Fy (0 °) at the scattering angle θ0 ° to the scattering characteristic (scattering intensity) Fy (10 °) at the scattering angle θ10 ° in the Y-axis direction. 10 °)] may be, for example, 20 or less (for example, about 1 to 20), preferably 15 or less, more preferably 10 or less (particularly 8 or less). If Fy (0 °) / Fy (10 °) is too large, the generation of through light increases.

  In order to prepare a sheet having such scattering characteristics, selection of components (particularly resin) constituting the continuous phase and the dispersed phase, molding conditions, particularly extrusion temperature, draw ratio after molding and cooling temperature are important. An anisotropic light diffusing layer is obtained by producing a sheet under the types and conditions described below.

  Note that the X-axis direction of the anisotropic light diffusion layer 1 is usually the long-axis direction of the elongated dispersed phase 1b. Therefore, the X-axis direction of the anisotropic light diffusing layer is arranged in a substantially gravitational direction (substantially vertical direction) in a state where the screen is installed. Note that the X-axis direction of the anisotropic light diffusing layer does not have to be completely parallel to the direction of gravity, for example, within an angle range of ± 15 ° (eg, ± 10 °, particularly ± 5 °). You may arrange | position toward the diagonal direction.

  The scattering characteristic F (θ) can be measured using, for example, a measuring apparatus as shown in FIG. This apparatus uses a scattering angle measurement device (for example, “Variable Photometer GP200” manufactured by Murakami Color Research Co., Ltd.) 2 and white light (C) transmitted through the anisotropic light diffusion layer 1 with respect to the anisotropic light diffusion layer 1. And a detector 3 for measuring the intensity of the light source. Then, white light is irradiated at an angle of 90 ° (perpendicularly) to the surface of the anisotropic light diffusion layer 1, and the intensity (scattered light intensity) F of the light diffused by the anisotropic light diffusion layer is expressed with respect to the scattering angle θ. The light scattering characteristics can be obtained by measuring (plotting).

  In the anisotropic light diffusing layer, if the anisotropy of light scattering is high, the angle dependency of scattering in a predetermined direction can be reduced, and therefore the angle dependency of luminance can also be reduced. In the anisotropic light diffusing layer, when an angle (90 °) perpendicular to the display surface is 0 °, a decrease in luminance can be suppressed even at an angle of 40 ° or more, exceeding an angle of 20 ° with respect to the display surface.

  The thickness of the anisotropic light diffusion layer is about 3 to 500 μm (for example, 3 to 300 μm), preferably about 5 to 200 μm (for example, 10 to 200 μm), more preferably about 15 to 150 μm (for example, 30 to 120 μm). Also good.

  The surface of the anisotropic light diffusing layer may be subjected to a surface treatment such as a corona discharge treatment as long as the optical characteristics are not hindered. Furthermore, you may form the uneven | corrugated | grooved part extended in the X-axis direction (long axis direction of a dispersed phase) of a sheet | seat in an anisotropic light-diffusion layer. When such an uneven part is formed, high anisotropic light scattering can be imparted.

(Transparent layer)
A transparent layer may be laminated on at least one surface of the anisotropic light diffusion layer. The transparent layer is not limited to one side of the anisotropic light diffusion layer, and may be laminated on both sides. The transparent layer protects the anisotropic light diffusion layer and prevents the long disperse phase from falling off and adheres, improving the scratch resistance and manufacturing stability of the anisotropic light diffusion layer, and the strength and handleability of the anisotropic light diffusion layer. Can be increased.

  As a transparent layer, not only a resin layer but various transparent base materials (for example, glass etc.) can be used. In many cases, the transparent layer is usually formed of a transparent resin layer.

  The transparent resin layer is a highly transparent resin such as a thermoplastic resin [polyolefin, cyclic polyolefin, halogen-containing resin (including fluororesin), vinyl alcohol resin, fatty acid vinyl ester resin, (meth) acrylic resin, Styrene resin, polyester, polyamide, polycarbonate, thermoplastic polyurethane, polysulfone resin (polyethersulfone, polysulfone, etc.), polyphenylene ether resin (polymer of 2,6-xylenol, etc.), cellulose esters, silicone resin (polydimethyl) Siloxane, polymethylphenylsiloxane, etc.), elastomer (nitrile-butadiene copolymer, rubber such as acrylic rubber, urethane rubber, silicone rubber, thermoplastic elastomer, etc.)], thermosetting resin (epoxy resin, etc.) , Unsaturated polyester resin, diallyl phthalate resin, a silicone resin) and the like. A preferred resin is a thermoplastic resin. The highly transparent resin may be an amorphous resin. As a specific example of the thermoplastic resin, a thermoplastic resin described in International Publication WO2009 / 016975 can be used.

  Preferred components constituting the transparent resin layer include polyolefin, (meth) acrylic resin, styrene resin, polyester, polyamide, polycarbonate and the like. A preferred transparent resin layer can be composed of polycarbonate. As the resin constituting the transparent resin layer, the same or different resin as the resin of the continuous phase and / or the elongated dispersed phase constituting the anisotropic light diffusion layer can be used as long as adhesion and mechanical properties are not impaired. However, usually, the same or common (or the same system) resin as the continuous phase resin is preferable.

  The transparent resin constituting the transparent resin layer is preferably a heat-resistant resin (such as a resin having a high glass transition temperature or a melting point) or a crystalline resin in order to improve heat resistance or blocking resistance. The glass transition temperature or melting point of the resin constituting the transparent resin layer may be, for example, about 130 to 280 ° C, preferably about 140 to 270 ° C, and more preferably about 150 to 260 ° C.

  Further, the transparent resin layer contains conventional additives such as stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), plasticizers, antistatic agents, flame retardants and the like. Also good. In particular, the transparent layer comprises a stabilizer (antioxidant, ultraviolet absorber, light stabilizer), preferably at least one component selected from an ultraviolet absorber and a light stabilizer (ultraviolet absorber alone, light stabilizer alone, It is preferably composed of a resin layer containing an ultraviolet absorber and a light stabilizer), particularly an ultraviolet absorber and a light stabilizer. As the stabilizer, the same components as described above can be used, and the amount of each stabilizer used and the total amount of the stabilizer with respect to 100 parts by weight of the resin component constituting the transparent resin layer is a ratio with respect to the resin component constituting the anisotropic light diffusion layer. You can select from the same range. Moreover, when using an ultraviolet absorber and a light stabilizer together, the ratio of both is from the range of the former / the latter (weight ratio) = 95 / 5-50 / 50 (for example, 90 / 10-70 / 30) grade. You can choose.

  The thickness of each transparent layer may be the same as that of the anisotropic light diffusion layer. For example, when the thickness of the anisotropic light diffusion layer is about 3 to 300 μm, the thickness of the transparent layer can be selected from about 3 to 150 μm. The ratio of the thickness of the anisotropic light diffusion layer and each transparent layer is, for example, light diffusion layer / transparent layer = about 5/95 to 99/1, preferably about 30/70 to 99/1, and more preferably 40/60. It is about ~ 95/5. The total thickness may be, for example, about 6 to 600 μm, preferably about 10 to 400 μm, and more preferably about 20 to 250 μm.

  The total light transmittance of the anisotropic light diffusion layer (when a transparent layer is laminated) is, for example, 50% or more (for example, 50 to 100%), preferably 60% or more (for example, 60 to 100%). In particular, it may be about 70 to 95% (for example, 75 to 90%). Furthermore, the haze of the anisotropic light diffusing layer (when a transparent layer is laminated) is 80% or more (for example, 80 to 99.9%), preferably 90% or more (for example, 90 to 99.8). %), More preferably 93 to 99.5%, particularly about 95 to 99%. If the total light transmittance is small, the luminance tends to decrease, and if the haze value is small, the light cannot be diffused uniformly and the viewing angle is decreased.

  The surface of the transparent layer may be subjected to a surface treatment such as a corona discharge treatment as long as the optical properties are not hindered.

(Isotropic light diffusion layer)
The isotropic light diffusing layer has an isotropic light scattering property. By combining with the anisotropic light diffusing layer, the anisotropic light diffusing layer suppresses a decrease in the anisotropic light diffusing property of the anisotropic light diffusing layer, and the anisotropic light diffusing layer. Viewing angle characteristics and visibility can be improved by scattering light passing through the layer.

  The isotropic light diffusion layer is not particularly limited as long as it has an isotropic light scattering property, and a light scattering sheet having conventional internal and / or external haze (scattering) can be used. The isotropic light diffusion layer may be a layer formed of a transparent binder resin and fine particles and having fine convex portions formed on the surface of the conventional light scattering sheet from the viewpoint of versatility. .

  Examples of the transparent binder resin include a conventional adhesive resin or adhesive resin. Examples of the adhesive resin include thermoplastic resins (polyolefin, cyclic polyolefin, acrylic resin, styrene resin, vinyl acetate resin, polyester, polyamide, thermoplastic polyurethane, etc.), thermosetting resins (epoxy resin, phenol resin, Polyurethane, unsaturated polyester, vinyl ester resin, diallyl phthalate resin, polyfunctional (meth) acrylate, urethane (meth) acrylate, silicone (meth) acrylate, silicone resin, amino resin, cellulose derivative and the like. Examples of the adhesive resin include terpene resins, rosin resins, petroleum resins, modified polyolefins, acrylic copolymers, silicone adhesives, and the like. These transparent binder resins may have a crosslinkable group (isocyanate group, hydroxyl group, carboxyl group, amino group, epoxy group, methylol group, alkoxysilyl group, etc.). These binder components can be used alone or in combination of two or more. Among these, acrylic resins such as polyfunctional (meth) acrylate, silicone (meth) acrylate, and urethane (meth) acrylate are preferable from the viewpoint of optical characteristics and light resistance.

  The fine particles may be either organic fine particles or inorganic fine particles. The organic fine particles may be uncrosslinked resin fine particles, but cross-linked resin fine particles are preferable from the viewpoint of shape retention. The crosslinked resin constituting the fine particles includes a crosslinked thermoplastic resin [for example, a crosslinked olefin resin (for example, crosslinked polyethylene, crosslinked polypropylene, etc.), a crosslinked styrene resin (for example, crosslinked polystyrene, crosslinked polydivinylbenzene, crosslinked polyvinyltoluene, Cross-linked styrene-methyl methacrylate copolymer, etc.), cross-linked acrylic resin (eg, cross-linked polymethyl methacrylate, etc.)], thermosetting resin (melamine resin, urea resin, aminobenzoguanamine resin, silicone resin, epoxy resin, polyurethane) Etc.). These organic fine particles can be used alone or in combination of two or more.

  Examples of the inorganic compound constituting the inorganic fine particles include metal simple substance, metal oxide (antimony trioxide, antimony tetroxide, antimony pentoxide, antimony-containing tin oxide, tin oxide, zinc oxide, titanium oxide, aluminum oxide, silicon oxide) Etc.), metal sulfate (calcium sulfate, barium sulfate, aluminum sulfate, etc.), metal silicate (calcium silicate, aluminum silicate, magnesium silicate, magnesium aluminosilicate, etc.), metal phosphate (calcium phosphate, magnesium phosphate, etc.), Metal carbonates (magnesium carbonate, heavy calcium carbonate, light calcium carbonate, etc.), metal hydroxides (aluminum hydroxide, calcium hydroxide, magnesium hydroxide, etc.), silicon compounds (white carbon, glass, etc.), natural minerals ( Zeolite, diatomaceous earth, baked珪成 earth, alumina, talc, mica, kaolin, sericite, bentonite, montmorillonite, smectite, etc. clays) and the like. These inorganic particles can be used alone or in combination of two or more.

  Of these fine particles, crosslinked acrylic resin particles, silicone resin particles, silica (silicon oxide) particles, and the like are preferable from the viewpoint of optical characteristics.

  The average particle diameter of the fine particles can be selected according to the thickness of the isotropic light diffusion layer, and is, for example, about 1 to 50 μm, preferably 2 to 40 μm, and more preferably about 3 to 30 μm. If the particle size is too small, the scattering property is lowered, and if it is too large, the scattering property is lowered.

  The shape of the fine particles may be an isotropic shape capable of forming a uniform concavo-convex structure on the surface and diffusing light in an isotropic manner. Etc. Of these, a substantially spherical shape and a granular shape are preferable because a uniform uneven structure can be formed and the isotropic light diffusibility is excellent.

  The fine particles are not only isotropic, but may be anisotropic as long as they are oriented in a random direction. From the viewpoint of excellent isotropic light diffusibility, the long axis average length L and short axis The ratio to the average length W (average aspect ratio, L / W) is, for example, about 1 to 3, preferably about 1 to 2, and more preferably about 1 to 1.5 (particularly 1 to 1.2). .

  The proportion of the fine particles is, for example, about 10 to 500 parts by weight, preferably about 50 to 300 parts by weight, and more preferably about 100 to 250 parts by weight with respect to 100 parts by weight of the transparent binder resin.

  The haze of the isotropic light diffusing layer is 65 from the point that, by combining with the anisotropic light diffusing layer, it is possible to suppress the generation of light passing through the anisotropic light diffusing layer and to suppress the anisotropic light diffusing anisotropy. -80%, for example, 68-79%, preferably 70-78%, more preferably 72-77% (particularly 73-76%). When the haze is too large, the anisotropic light diffusibility of the anisotropic light diffusing layer is lowered, and when the haze is too small, the anisotropic light diffusing layer passes through and the scattering property and visibility are lowered. In the present invention, by adjusting the haze of the isotropic light diffusing layer to the above range, while maintaining the anisotropic diffusivity of the anisotropic light diffusing layer, although the light is diffused by the isotropic light diffusing layer, Scattering efficiency is improved.

  The isotropic property of the isotropic light diffusing layer is determined by the method of measuring anisotropy in the anisotropic light diffusing layer (the X-axis direction and the Y-axis direction of the anisotropic light diffusing layer when the isotropic light diffusing layer and the anisotropic light diffusing layer are laminated). In the method of measuring the scattered light intensity of the isotropic light diffusion layer), the value of Fy (θ) / Fx (θ) is about 0.7 to 1.3 in the range of the scattering angle θ = 4 to 30 °. For example, it is about 0.8 to 1.2, preferably about 0.9 to 1.1.

  Further, since the isotropic light diffusion layer does not reduce the anisotropic diffusion property of the anisotropic light diffusion layer, it is preferable that the scattering angle is not too large (not too wide) and is in an appropriate range, and is 0 ° in any direction. The angle at which the scattering intensity is 1/3 times the scattering intensity (scattering intensity perpendicular to the surface of the laminate) may be 8 ° or less (for example, 2 to 8 °). It may be about -7.5 °, preferably 3.5-7 ° (for example, 4-6.5 °), more preferably about 5-6.2 ° (especially 5.5-6 °). Further, the angle at which the scattering intensity becomes 1/10 times the scattering intensity of 0 ° may be 17 ° or less (for example, 5 to 17 °), for example, 5.5 to 15 °, preferably 6 to It may be about 12 ° (for example, 7 to 11.5 °), more preferably about 8 to 11 ° (particularly 9 to 10 °). If these angles are too large, the anisotropic light diffusibility of the anisotropic light diffusing layer decreases, and if it is too small, the generation of through light cannot be effectively suppressed.

  The isotropic light diffusing layer includes various conventional additives such as curing agents, crosslinking agents, photopolymerization initiators, photopolymerization accelerators, stabilizers (antioxidants, ultraviolet absorbers, etc.), surfactants, water-soluble agents. Polymers, fillers, crosslinking agents, coupling agents, colorants, flame retardants, lubricants, waxes, preservatives, viscosity modifiers, thickeners, leveling agents, antifoaming agents, and the like may be included.

  The thickness of the isotropic light diffusion layer can be selected from a range of about 1 to 100 μm, and is, for example, about 2 to 50 μm, preferably 3 to 40 μm, and more preferably 4 to 30 μm (particularly 5 to 20 μm). If the thickness is too large, it will be difficult to form convex portions on the surface, and if it is too small, the film strength will decrease.

  The transparent layer exemplified in the section of the anisotropic light diffusion layer may be laminated on at least one surface of the isotropic light diffusion layer.

(Characteristics of anisotropic light diffusion laminate)
The anisotropic light diffusing laminate of the present invention is excellent in anisotropic light diffusibility, and against the light diffusibility in the longitudinal direction of the elongated dispersed phase of the anisotropic light diffusing layer (the direction of gravity in the state where a screen is provided). The light diffusibility in the direction perpendicular to the longitudinal direction (the horizontal direction in the state where the screen is disposed) is large.

  Specifically, in the longitudinal direction of the long dispersed phase, the angle at which the scattering intensity becomes 1/10 times the 0 ° scattering intensity (the scattering intensity at an angle perpendicular to the laminate surface) is small, for example, The angle may be 15 ° or less, preferably 14 ° or less (for example, about 5 to 14 °), and more preferably 13.5 ° or less (for example, about 10 to 13.5 °). When this angle exceeds 15 °, the scattering characteristics in the longitudinal direction of the elongated dispersed phase increase, and the visibility of the screen decreases due to a decrease in luminance or the like.

  On the other hand, in the direction perpendicular to the longitudinal direction of the elongated dispersed phase, the angle at which the scattering intensity is ½ times the 0 ° scattering intensity is large. For example, the angle is 8 ° or more, preferably It may be 8.5 ° or more (for example, about 8.5 to 15 °), more preferably 9 ° or more (particularly about 9.5 to 13 °). When this angle is less than 8 °, the scattering characteristic in the direction perpendicular to the longitudinal direction of the elongated dispersed phase is lowered, and the viewing angle characteristic is lowered.

  The anisotropic light diffusion laminate of the present invention only needs to include an anisotropic light diffusion layer and an isotropic light diffusion layer, and each layer may be formed of a plurality of layers, but in combination with other functional layers Is easy and also has sufficient light diffusivity, so a combination of single layers is preferable.

[Method for producing anisotropic light diffusion laminate]
The anisotropic light diffusion laminate can be obtained by a method in which an anisotropic light diffusion layer and an isotropic light diffusion layer are bonded together via an adhesive layer, or a method in which an isotropic light diffusion layer is formed on the anisotropic light diffusion layer by coating.

  The anisotropic light diffusion layer can be prepared by dispersing the resin component constituting the long dispersed phase in the resin constituting the continuous phase, and deforming the anisotropic light diffusion layer and the resin component constituting the long dispersed phase. It can be obtained by aligning. For example, a polycarbonate resin and a polypropylene resin and, if necessary, components such as a compatibilizing agent are blended by a conventional method (for example, a melt blending method, a tumbler method, etc.) as necessary, and melt-mixed to form a T die or a ring. The dispersed phase can be dispersed by extrusion from a die or the like to form a film. Also, a coating method in which a composition composed of a particulate polypropylene resin as a light scattering component and a polycarbonate resin is applied onto a substrate (such as a substrate film), or a laminating method in which the composition is laminated The light diffusion film can also be produced by molding using a conventional film molding method such as a casting method or an extrusion molding method. Usually, an anisotropic light diffusion layer is often prepared by film forming by an extrusion method.

  When forming a transparent resin layer on at least one surface of the anisotropic light diffusion layer, a resin composition composed of a component corresponding to the anisotropic light diffusion layer and a resin composition composed of a component corresponding to the transparent resin layer A coextrusion molding method in which a product is coextruded and formed into a film, a method in which the other layer is laminated by extruding one layer prepared in advance, and an anisotropic light diffusing layer and a transparent resin layer respectively produced. It can be formed by a dry laminating method or the like.

  For example, (1) a method of forming a film while drawing an extruded sheet, (2) a method of uniaxially stretching the extruded sheet, (3) the method of (1) and (2) (4) A method of combining the above components with a solution and forming a film by a casting method.

  The melting temperature may be, for example, about 150 to 270 ° C, preferably about 200 to 260 ° C, and more preferably about 230 to 255 ° C.

  In order to develop appropriate anisotropy, the anisotropic light diffusion layer is preferably formed while drawing an extruded sheet during melt film formation. In order to exhibit a predetermined anisotropic light diffusion characteristic, it is important to adjust the draw ratio after extrusion. The draw ratio (draw ratio) can be selected from a range of about 1.5 to 50 times depending on the opening degree of the die of the extruder, the type of resin, the layer structure, etc., and cannot be uniquely determined. In this case, for example, the anisotropic parameter is selected from the range of about 4 to 40 times, preferably 5 to 35 times, and more preferably 8 to 30 times (particularly 10 to 25 times). it can. When the transparent layer is laminated, since the anisotropy tends to be higher than that of the single layer, the draw ratio is, for example, 3.5 to 20 times, preferably 4 to 18 times, and more preferably 5 to 16 times. It may be about twice (especially 6 to 15 times).

  The cooling temperature by a cast roll etc. may be about 30-110 degreeC, for example, Preferably it is 40-100 degreeC, More preferably, about 60-90 degreeC may be sufficient. Furthermore, the anisotropic light diffusion layer may be stretched (uniaxial or biaxial stretching, particularly uniaxial stretching). The draw ratio of the anisotropic light diffusion layer can be selected according to the aspect ratio of the dispersed phase. For example, the draw ratio in one direction is 1.1 to 10 times, preferably 1.2 to 5 times, more preferably 1.5. It may be about 3 times.

  The isotropic light diffusing layer can be manufactured by a conventional method, but the isotropic light diffusing layer formed of fine particles and a transparent binder resin is usually manufactured by a coating method, a casting method, an extrusion method, etc., and the transparent binder resin is cured. In the case of an adhesive resin, it can be obtained by applying a coating liquid containing a transparent binder resin and fine particles on a substrate, drying and then curing.

  As a coating method, for example, spray, roll coater, air knife coater, blade coater, rod coater, reverse coater, bar coater, comma coater, dip squeeze coater, die coater, gravure coater, micro gravure coater, silk Examples include screen coater method, dip method, spray method, spinner method and the like. Of these methods, the bar coater method and the gravure coater method are widely used. If necessary, the coating solution may be applied a plurality of times.

  The coating liquid may contain a solvent, and after casting or coating the mixed liquid, the solvent is evaporated. The solvent is usually evaporated at a temperature of about 30 to 200 ° C. (for example, 30 to 100 ° C.), preferably 40 to 120 ° C., more preferably about 40 to 80 ° C., depending on the boiling point of the solvent. May be.

  The isotropic light diffusing layer in which the concavo-convex structure is formed by fine particles may be finally cured by actinic rays (ultraviolet rays, electron beams, etc.) or heat to form a cured resin. The curing method may be a combination of heating, light irradiation, etc. depending on the type of resin.

  In the method of forming an isotropic light diffusing layer on the anisotropic light diffusing layer by coating, the anisotropic light diffusing layer and the isotropic light are obtained by using the anisotropic light diffusing layer as a base material in the manufacturing method of such an isotropic light diffusing layer. The diffusion layer can be integrated.

  In the method of laminating the anisotropic light diffusion layer and the isotropic light diffusion layer via the adhesive layer, the adhesive layer may be the same adhesive resin or adhesive as the transparent binder resin in the isotropic light diffusion layer (especially an acrylic adhesive). Etc.) can be used. The thickness of the adhesive layer is, for example, about 1 to 50 μm, preferably 2 to 30 μm, and more preferably about 3 to 20 μm.

[Projector screen]
The projector screen of the present invention includes the anisotropic light diffusion laminate. Since the projector screen of the present invention can selectively diffuse light in the horizontal direction by arranging the longitudinal direction of the elongated dispersed phase in the direction of gravity, the viewing angle characteristics of the screen can be improved. The projector screen may be either a reflective (front type) screen or a transmissive (rear type) screen, and conventional components can be used as components other than the anisotropic light diffusion laminate.

  In the case of the reflection type, the substrate can be a wall, an inorganic plate (glass plate, metal plate, etc.), a wooden board, a fabric (paper, woven fabric, knitted fabric, non-woven fabric, etc.), a plastic sheet, or the like. Of these, plastic sheets are preferred. Examples of the plastic sheet include a thermoplastic resin and a thermosetting resin formed with a transparent resin layer.

  In the reflection type, a reflection layer is usually formed on the substrate. The reflection layer only needs to have a light reflecting material, and examples thereof include a layer containing metal particles and a pigment (such as a brilliant pigment such as a pearl pigment) and a layer formed of a metal foil. Of these, a layer formed of a metal foil is preferable from the viewpoint of excellent reflectivity. Examples of the metal constituting the metal foil include titanium, nickel, copper, silver, zinc, aluminum, and tin. Of these, aluminum and silver are widely used. The metal foil may be a vapor deposition film or a film formed by sputtering or the like. In the case of metal foil, the thickness of the reflective layer may be, for example, about 10 to 200 nm, preferably about 20 to 150 nm, and more preferably about 30 to 100 nm.

  In the transmissive type, a transparent material or a translucent material is used as the base material among the reflective base materials, and a transparent plastic sheet or the like is usually used.

  The screen is either a reflective type or a transmissive type, and a conventional functional layer such as an antireflection layer, a wavelength correction layer, a deflection layer, a low refractive index layer, a high refractive index layer, a light absorption layer (dye-containing layer), A hard coat layer may be further included.

  In the present invention, a reflective screen is preferable from the viewpoint that visibility such as luminance can be remarkably improved even if it has high anisotropic light diffusion characteristics. The anisotropic light diffusing laminate of the present invention can suppress light diffusion in the direction of gravity due to reflection of the isotropic light diffusing layer, and can improve anisotropic light diffusibility and luminance in a reflective screen. Is preferably disposed so as to be located on the surface side of the screen.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In addition, the anisotropic light-diffusion film used by the Example and the comparative example and the characteristic of the surface light source device using the same were evaluated in accordance with the following method.

[Total light transmittance TT (%) and haze (%)]
Based on JISK7301, the total light transmittance and haze of the film were measured using the haze meter (Nippon Denshoku Industries Co., Ltd. make, NDH-500).

[aspect ratio]
Observe the cross section of the anisotropic light diffusion layer with a transmission electron microscope (TEM), measure the long axis length and short axis length of the long disperse phase for 5 disperse phase particles, add and average, and average aspect ratio Was calculated.

[Scattering characteristics]
The scattering characteristic F (θ) of the anisotropic light diffusion layer was measured using a measuring apparatus as shown in FIG. This apparatus has a scattering angle measuring device (“Molecular Photometer GP200” manufactured by Murakami Color Research Laboratory Co., Ltd.) 2 for the anisotropic light diffusing layer 1 and white light (C light source) transmitted through the anisotropic light diffusing layer 1. And a detector 3 for measuring the intensity of the. Then, white light is irradiated at an angle of 90 ° (perpendicularly) to the surface of the anisotropic light diffusion layer 1, and the intensity (scattered light intensity) F of the light diffused by the anisotropic light diffusion layer is expressed with respect to the scattering angle θ. The light scattering characteristics were determined by measuring (plotting). For the anisotropic light diffusion layer, the scattering intensity was measured in the longitudinal direction of the elongated dispersed phase and the direction perpendicular to the longitudinal direction.

  For the isotropic light diffusion layer and the anisotropic light diffusion laminate, the scattering intensity is measured in the same manner. For the isotropic light diffusion layer, the scattering intensity is measured in an arbitrary direction. The scattering intensity was measured in the longitudinal direction of the scale-like dispersed phase and the direction perpendicular to the longitudinal direction.

Example 1
To produce an anisotropic light diffusing layer with a transparent resin layer laminated on both sides (light diffusing plate with an anisotropic light diffusing layer as an intermediate layer and a transparent resin layer as a surface layer on both sides of this intermediate layer) As a resin composition for an intermediate layer, a polycarbonate resin (manufactured by Mitsubishi Engineering Plastics Co., Ltd., “Iupilon S-2000”, number average molecular weight 18000-20000, melt flow rate 9-12 g / 10 min) is used. As a resin constituting a continuous phase, 92 parts by weight of a polycarbonate resin (manufactured by Mitsubishi Engineering Plastics Co., Ltd., “Iupilon S-2000”), a polypropylene resin as a resin constituting a dispersed phase (manufactured by Nippon Polypro Co., Ltd.) , “Wintech WFX-4”, propylene random copolymer using metallocene catalyst, melt Low rate 7 g / 10 min) was used 8 parts by weight. The resin composition constituting each layer is mixed, and is melted and co-extruded from a die at a resin temperature of 250 ° C. and a die opening of 1.3 mm with a multilayer extruder, and the draw ratio (draw ratio) is set to 7.7 times. An oil temperature control three cast roll was cooled at 80 ° C. to produce an anisotropic light diffusion layer A (total thickness 175 μm, transparent resin layer thickness 35 μm, anisotropic light diffusion layer thickness 105 μm) formed with transparent resin layers on both sides. .

  The total light transmittance of the obtained anisotropic light diffusion layer A (laminate) was 89%. Table 1 shows the measurement results of the light scattering characteristics of the anisotropic light diffusion layer A (laminate). Further, when a cross section was observed with a transmission electron microscope (TEM), in the anisotropic light diffusion layer, polypropylene formed a scatterer (elongated dispersed phase), and the shape of the elongated dispersed phase was an elongated line. The average length of the short axis was 0.20 μm and the average length of the long axis was 133.3 μm (aspect ratio 667).

  Regarding the relationship between the scattering angle and the scattering intensity of the obtained anisotropic light diffusion layer (laminated body), the longitudinal direction (vertical direction) of the long dispersed phase and the direction perpendicular to the longitudinal direction (horizontal direction) The measured graph is shown in FIG. As is apparent from FIG. 3, the scattering intensity was high at a scattering angle of 0 °, and generation of through light was observed.

  The obtained anisotropic light diffusing layer A (laminate) and the isotropic light diffusing layer ("Opulse BMUIS" manufactured by Keiwa Co., Ltd., 75% haze) were combined with an adhesive layer having a thickness of 25 μm ("Panaclean" manufactured by Panac Co., Ltd.). PD-S1 ") to obtain an anisotropic light diffusion laminate (different A + etc. 75: a combination of an anisotropic light diffusion layer A and an isotropic light diffusion layer having a haze of 75%. The same applies hereinafter). It was.

In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle (1 / 10I ₀ -V) that is 1/10 times the scattering intensity of 1/10 times the 0 ° scattering intensity, and is 12.7 °. In the direction perpendicular to the longitudinal direction of the long dispersed phase, the angle (1 / 2I ₀ -H) at which the scattering intensity is ½ times the 0 ° scattering intensity was 9.7 °.

  FIG. 4 shows a graph of the relationship between the scattering angle and the scattering intensity of the obtained anisotropic light diffusion layer (laminated body) measured in each of the longitudinal direction of the long dispersed phase and the direction perpendicular to the longitudinal direction. . As is apparent from FIG. 4, no voids occurred and the anisotropic light diffusibility was high.

Example 2
An anisotropic light diffusion layer B (total thickness 175 μm, transparent resin layer thickness 35 μm, anisotropic light diffusion) with transparent resin layers formed on both sides in the same manner as in Example 1 except that the draw ratio of coextrusion is 5.2 times A layer thickness of 105 μm) was produced.

  The total light transmittance of the obtained anisotropic light diffusion layer B (laminate) was 80%. Table 1 shows the measurement results of the light scattering characteristics of the anisotropic light diffusion layer B (laminate). Further, when a cross section was observed with a TEM, polypropylene formed a scatterer (long dispersion phase) in the anisotropic light diffusion layer, and the shape of the elongated dispersion phase was an elongated linear shape, and the short axis The average length was 0.5 μm, and the average length of the long axis was 75 μm (aspect ratio 150).

  The obtained anisotropic light diffusing layer B (laminate) and the isotropic light diffusing layer ("Opulse BMUIS" manufactured by Keiwa Co., Ltd., 75% haze) are passed through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm. To obtain an anisotropic light diffusion laminate (different B + etc. 75).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle at which the scattering intensity is 1/10 times the 0 ° scattering intensity is 13.1 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity is ½ times the 0 ° scattering intensity was 9.5 °.

Example 3
An anisotropic light diffusing layer A (total thickness 125 μm, transparent resin layer thickness 25 μm, anisotropic light diffusing layer thickness 75 μm) obtained in the same manner as in Example 1, and an isotropic light diffusing layer (Eupulse Co., Ltd. “Opulse”) ”, Haze 80%) was bonded together via an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different A + etc. 80).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle of 14.7 ° that is 1/10 times the scattering intensity of 0 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity was ½ times the 0 ° scattering intensity was 12.2 °.

Example 4
An anisotropic light diffusing layer A (total thickness 125 μm, transparent resin layer thickness 25 μm, anisotropic light diffusing layer thickness 75 μm) obtained in the same manner as in Example 1, and an isotropic light diffusing layer (Eupulse Co., Ltd. “Opulse”) ”, Haze 78.4%) was bonded through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different A + etc. 78.4).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle at which the scattering intensity is 1/10 times the scattering intensity of 0 ° with respect to 0 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity was ½ times the 0 ° scattering intensity was 11.8 °.

Example 5
An anisotropic light diffusing layer A (total thickness 125 μm, transparent resin layer thickness 25 μm, anisotropic light diffusing layer thickness 75 μm) obtained in the same manner as in Example 1, and an isotropic light diffusing layer (Eupulse Co., Ltd. “Opulse”) The haze 71.6%) was bonded through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different A + etc. 71.6).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle at which the scattering intensity is 1/10 times the scattering intensity of 0 ° with respect to 0 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity is ½ times the scattering intensity of 0 ° was 9.6 °.

Comparative Example 1
An anisotropic light diffusion layer C (total thickness 95 μm, transparent resin layer thickness 20 μm, anisotropic light diffusion) in which transparent resin layers were formed on both sides in the same manner as in Example 1 except that the draw ratio of coextrusion was 9.5 times A layer thickness of 55 μm) was produced.

  The total light transmittance of the obtained anisotropic light diffusion layer C (laminate) was 95%. Table 1 shows the measurement results of the light scattering characteristics of the anisotropic light diffusion layer C (laminate). Further, when a cross section was observed with a TEM, polypropylene formed a scatterer (long dispersion phase) in the anisotropic light diffusion layer, and the shape of the elongated dispersion phase was an elongated linear shape, and the short axis The average length was 0.15 μm and the average length of the major axis was 205 μm (aspect ratio 1367).

  The obtained anisotropic light diffusing layer C (laminate) and the isotropic light diffusing layer ("Opulse BMUIS" manufactured by Eiwa Co., Ltd., haze 75%) are passed through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm. To obtain an anisotropic light diffusion laminate (different C + etc. 75).

  In the longitudinal direction of the long dispersion phase, the obtained laminate has an angle of 11.5 ° that is 1/10 times the scattering intensity of 1 ° with respect to the 0 ° scattering intensity, and the longitudinal direction of the long dispersion phase. In the direction perpendicular to the angle, the angle at which the scattering intensity is ½ times the 0 ° scattering intensity was 6.3 °. The results are shown in Table 2.

Comparative Example 2
An anisotropic light diffusing layer A (total thickness 125 μm, transparent resin layer thickness 25 μm, anisotropic light diffusing layer thickness 75 μm) obtained in the same manner as in Example 1, and an isotropic light diffusing layer (Eupulse Co., Ltd. “Opulse”) The haze (86.0%) was bonded through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different A + etc. 86).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle of 15.5 ° that is 1/10 times the scattering intensity of 0 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity is ½ times the scattering intensity of 0 ° was 14.2 °.

  FIG. 5 shows a graph obtained by measuring the relationship between the scattering angle and the scattering intensity of the obtained anisotropic light diffusion layer (laminated body) in the longitudinal direction of the elongated dispersed phase and the direction perpendicular to the longitudinal direction. . As is clear from FIG. 5, the generation of through light was not observed, but the isotropic light diffusibility was exhibited.

Comparative Example 3
An anisotropic light diffusing layer A (total thickness 125 μm, transparent resin layer thickness 25 μm, anisotropic light diffusing layer thickness 75 μm) obtained in the same manner as in Example 1, and an isotropic light diffusing layer (Eupulse Co., Ltd. “Opulse”) The haze of 55.8%) was bonded through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different A + etc. 55.8).

  In the longitudinal direction of the long dispersion phase, the obtained laminate has an angle of 11.4 ° that is 1/10 times the scattering intensity of 0 ° with respect to the 0 ° scattering intensity, and the longitudinal direction of the long dispersion phase. In the direction perpendicular to the angle, the angle at which the scattering intensity was ½ times the 0 ° scattering intensity was 7.7 °. The results are shown in Table 2.

Comparative Example 4
An anisotropic light diffusing layer B (total thickness 175 μm, transparent resin layer thickness 35 μm, anisotropic light diffusing layer thickness 105 μm) obtained in the same manner as in Example 2, and an isotropic light diffusing layer (Opulse manufactured by Keiwa Co., Ltd. ”, A haze of 60.4%) was bonded through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different B + etc. 60.4).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle of 10.6 ° that is 1/10 times the scattering intensity of 0 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity is ½ times the scattering intensity of 0 ° was 7.4 °.

Comparative Example 5
An anisotropic light diffusing layer C (total thickness 95 μm, transparent resin layer thickness 20 μm, anisotropic light diffusing layer thickness 55 μm) obtained in the same manner as in Comparative Example 1, and an isotropic light diffusing layer (Opas Co., Ltd. The haze (82.7%) was bonded through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different C + etc. 82.7).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle of 13.7 ° that is 1/10 times the scattering intensity of 0 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity was ½ times the 0 ° scattering intensity was 8.1 °.

Comparative Example 6
An anisotropic light diffusing layer A (total thickness 125 μm, transparent resin layer thickness 25 μm, anisotropic light diffusing layer thickness 75 μm) obtained in the same manner as in Example 1, and an isotropic light diffusing layer (Eupulse Co., Ltd. “Opulse”) The haze of 82.7%) was bonded through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different A + etc. 82.7).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle of 15.5 ° that is 1/10 times the scattering intensity of 0 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity is ½ times the scattering intensity of 0 ° was 13.2 °.

Comparative Example 7
An anisotropic light diffusing layer A (total thickness 125 μm, transparent resin layer thickness 25 μm, anisotropic light diffusing layer thickness 75 μm) obtained in the same manner as in Example 1, and an isotropic light diffusing layer (Eupulse Co., Ltd. “Opulse”) ”, A haze of 60.4%) was bonded through an adhesive layer (Panaclean PD-S1) having a thickness of 25 μm to obtain an anisotropic light diffusion laminate (different A + etc. 60.4).

  In the longitudinal direction of the elongated dispersed phase, the obtained laminate has an angle of 9.8 ° that is 1/10 times the scattering intensity of 0 °, and the longitudinal direction of the elongated dispersed phase. In the direction perpendicular to the angle, the angle at which the scattering intensity is ½ times the 0 ° scattering intensity was 6.4 °.

The angle (1 / 3I ₀ ) at which the scattering intensity is 1/3 times the 0 ° scattering intensity of the light scattering profile of the isotropic light diffusion layer (and other isotropic light diffusion layers) used in Examples and Comparative Examples. ) And the angle at which the scattering intensity is 1/10 times (1/10 I ₀ ) is shown in Table 2.

  Furthermore, Table 3 shows the results of the scattering characteristics of the anisotropic light diffusing laminates obtained in Examples and Comparative Examples.

  As is apparent from the results in Table 1, the anisotropic light diffusion layer A has Fy (0 °) / Fy (10 °) [scattering characteristics (scattering characteristics at a scattering angle θ10 ° in the direction perpendicular to the longitudinal direction of the elongated dispersed phase). Intensity) ratio of scattering characteristic Fy (0 °) at scattering angle θ0 ° to Fy (10 °)] is small, there is little through light, and the anisotropic property at scattering angles 5 ° and 10 ° is also large. Excellent balance as a diffusion layer.

  As is apparent from the results in Table 3, the anisotropic light diffusion laminates of the examples are excellent in anisotropic light scattering characteristics and can improve the viewing angle in the horizontal direction. In particular, the laminate using the anisotropic light diffusing layer A can easily improve the viewing angle in the horizontal direction while maintaining the visibility by controlling the light diffusing characteristics of the isotropic light diffusing layer. It is.

  The anisotropic light diffusing laminate of the present invention includes various projectors such as OHP, slide projector, CRT (cathode tube display) projector (CRT projector, etc.), light valve projector [liquid crystal projector, digital light processing ( DLP) projectors, liquid crystal on silicon (LCOS) projectors, grating light valve (GLP) projectors, and the like]. The projector screen may be either a transmissive screen or a reflective screen, but is particularly useful for a reflective screen.

Claims (10)

An anisotropic light diffusion laminate included in a screen for displaying an image projected from a projector,
Including an anisotropic light diffusion layer and an isotropic light diffusion layer,
The anisotropic light diffusion layer is formed of a continuous phase containing a polycarbonate resin and an elongated dispersed phase containing a polypropylene resin,
An average aspect ratio of the elongated dispersed phase is 100 or more, and a major axis direction of the elongated dispersed phase is oriented in a certain direction of the anisotropic light diffusion layer;
In the scattering characteristic F (θ) in which the anisotropic light diffusing layer is oriented in the longitudinal direction of the elongated dispersed phase in a certain direction of the anisotropic light diffusing layer and shows the relationship between the scattering angle θ and the scattered light intensity F When the scattering characteristic in the longitudinal direction of the elongated dispersed phase is Fx (θ) and the scattering characteristic in the direction perpendicular to the longitudinal direction of the elongated dispersed phase is Fy (θ), the scattering angle θ = 5 °. 2 ≦ Fy (θ) / Fx (θ) ≦ 20,
An anisotropic light diffusion laminate in which the isotropic light diffusion layer has a haze of 65 to 80%.   The anisotropic light-diffusion laminated body of Claim 1 whose haze of an isotropic light-diffusion layer is 70 to 78%.   The anisotropic light diffusion laminate according to claim 1, wherein the anisotropic light diffusion layer has a scattering angle of θ = 5 ° and satisfies 5 ≦ Fy (θ) / Fx (θ) ≦ 15.   In the direction perpendicular to the longitudinal direction of the elongated dispersed phase, the angle at which the scattering intensity becomes 1/10 times the scattering intensity of 0 ° is 15 ° or less, and perpendicular to the longitudinal direction of the elongated dispersed phase. The anisotropic light-diffusion laminated body in any one of Claims 1-3 whose angle which becomes a scattering intensity 1/2 time with respect to 0 degree scattering intensity in a direction is 8 degrees or more.   The anisotropic light-diffusion laminated body in any one of Claims 1-4 with which the anisotropic light-diffusion layer and the isotropic light-diffusion layer are integrated through the contact bonding layer.   The anisotropic light-diffusion laminated body in any one of Claims 1-5 in which the isotropic light-diffusion layer is integrated with the anisotropic light-diffusion layer by forming with a coating on an anisotropic light-diffusion layer.   The anisotropic light diffusion laminate according to claim 1, wherein a transparent layer is formed on at least one surface of the anisotropic light diffusion layer, and the transparent layer and the isotropic light diffusion layer are integrated.   The anisotropic light diffusion laminate according to any one of claims 1 to 7, wherein the polycarbonate resin is a polycarbonate resin having a number average molecular weight of 15,000 to 25,000, and the polypropylene resin is a metallocene catalyst resin.   The projector screen containing the anisotropic light-diffusion laminated body in any one of Claims 1-8.   The projector screen according to claim 9, wherein the projector screen is a reflective screen and an anisotropic light diffusion layer is disposed on the surface side.