WO2009098992A1

WO2009098992A1 - Light-diffusing layered resin film, process for producing the same, antiglare film, antiglare polarizer, and image display

Info

Publication number: WO2009098992A1
Application number: PCT/JP2009/051448
Authority: WO
Inventors: Seiji Muro; Yasuhiro Watanabe; Tomohiro Maekawa
Original assignee: Sumitomo Chemical Company, Limited
Priority date: 2008-02-06
Filing date: 2009-01-29
Publication date: 2009-08-13
Also published as: JP2009211055A; TW200941043A

Abstract

A light-diffusing layered resin film which comprises a resin layer (A) comprising a transparent resin containing a light diffuser dispersed therein having a weight-average particle diameter of 1-20 µm and a transparent resin layer (B) superposed on each side of the resin layer (A), and which has a thickness of 30-500 µm. The resin layer (A) has a thickness which is 5-50%, excluding 50%, of the thickness of the light-diffusing layered resin film. The light-diffusing layered resin film is produced by obtaining a layered film by the coextrusion of a resin composition for forming the resin layer (A) and a resin composition for forming the transparent resin layers (B) and forming the layered film while keeping at least one side of the layered film in contact with an elastic roll. Also provided are: a process for producing the light-diffusing layered resin film; and an antiglare film, antiglare polarizer, and image display each employing the light-diffusing resin film.

Description

Light diffusing laminated resin film and manufacturing method thereof, antiglare film, antiglare polarizing plate and image display device

The present invention relates to a light diffusing laminated resin film based on a transparent resin and a method for producing the same, and more particularly to a light diffusing laminated resin film having excellent surface smoothness and a method for producing the same. The present invention also relates to an antiglare (antiglare) film using the light diffusing laminated resin film, and an antiglare polarizing plate and an image display device using the antiglare film.

A film having light diffusing properties is bonded to a transparent substrate to form a light diffusing plate, which can be applied to lighting covers, lighting signs, etc., or to impart light diffusing functions and lens functions to liquid crystal TVs, projection TVs, etc. It is used for various purposes such as application to other members.

Conventionally, the light diffusion property is imparted to the resin film by a method of dispersing transparent fine particles having a specific particle diameter and a refractive index different from that of the base material in the transparent resin as the base material (for example, JP-A-3-237133 (Patent Document 1)), a method of coating fine particles on the surface of a substrate made of a transparent resin (for example, JP-A-6-59108 (Patent Document 2)), unevenness on the surface of a resin film Has been carried out by a method of transferring the toner (for example, JP-A-2000-267088 (Patent Document 3)).

Here, in the case of applying a film having a light diffusing property to the above-mentioned uses, etc., often the light diffusing film is bonded to another film or a resin substrate using an adhesive or an adhesive, or cured. A new additional function is imparted by applying a curing resin to the surface of the light diffusing film and curing it. However, in such a case, when the conventional light diffusing film is used, an interface between the light diffusing film and another film, a curable resin layer, or the like is caused by the unevenness of the surface of the light diffusing film. There was a problem of becoming unstable. For example, when trying to integrate a light diffusive film with another film, air bubbles are likely to enter the interface due to the surface irregularities of the light diffusive film, and when it is pasted so that air bubbles do not enter, it is laminated. There was a problem that the film was very difficult to process, such as a large warp. Furthermore, in the bonding process, the unevenness on the surface of the light diffusing film may disappear due to the adhesive component filling the unevenness on the surface of the light diffusing film, but in this case, the light diffusion characteristics before and after processing are large. There was a problem that it would change and affect the design of the final product.
JP-A-3-237133 JP-A-6-59108 JP 2000-267088 A

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a light diffusing resin film having a smooth surface and less unevenness and a method for producing the same. Another object of the present invention is to provide an antiglare film using such a light diffusing resin film, and an antiglare polarizing plate and an image display device using the antiglare film.

The present invention relates to a resin layer (A) made of a transparent resin in which a light diffusing agent having a weight average particle size of 1 to 20 μm is dispersed, and a transparent resin layer (B) laminated on both surfaces of the resin layer (A). And a thickness of the resin layer (A) is 5% or more and less than 50% of the thickness of the light diffusable laminated resin film, In a state where at least one surface of the laminated film obtained by coextrusion molding using the resin composition forming the resin layer (A) and the resin composition forming the transparent resin layer (B) is in contact with an elastic roll, A light diffusing laminated resin film formed by molding the laminated film is provided. The resin layer (A) preferably contains 5 to 40 parts by weight of a light diffusing agent with respect to 100 parts by weight of the transparent resin.

In the present invention, the least one of the transparent resin layer (B), the arithmetic mean roughness R _a of the resin layer (A) side of the opposite surface is preferably 0 ~ 0.5 [mu] m. Moreover, it is preferable that the transparent resin layer (B) side surface of the resin layer (A) and the resin layer (A) side surface of the transparent resin layer (B) are in contact.

The transparent resin layer (B) is composed of a methyl methacrylate resin, a resin composition containing a rubber polymer in a methyl methacrylate resin, a styrene resin, an aromatic polycarbonate resin, an alicyclic structure-containing ethylenically unsaturated monomer. It is preferable that it consists of resin containing a monomer unit, or these 2 or more types of mixed resin. The transparent resin includes a methyl methacrylate resin, a resin composition in which a rubber-like polymer is contained in a methyl methacrylate resin, a styrene resin, and a resin composition in which a rubber-like polymer is contained in a styrene resin. It is preferable that it is a thing, an aromatic polycarbonate resin, or these 2 or more types of mixed resin.

The present invention also provides a resin layer (A) made of a transparent resin in which a light diffusing agent having a weight average particle diameter of 1 to 20 μm is dispersed, and a transparent resin layer (A) laminated on both surfaces of the resin layer (A) ( B) and a method for producing a light-diffusing laminated resin film having a thickness of 30 to 500 μm. The method for producing a light diffusing laminated resin film of the present invention is a laminated film obtained by coextrusion molding using a resin composition forming a resin layer (A) and a resin composition forming a transparent resin layer (B). A step of forming the laminated film so that the thickness of the resin layer (A) is 5% or more and less than 50% of the thickness of the light diffusing laminated resin film in a state where at least one surface thereof is in contact with the elastic roll. Is.

Further, according to the present invention, there is provided an antiglare film comprising the light diffusing laminated resin film of the present invention and a hard coat layer laminated on the surface of the light diffusing laminated resin film and having a fine uneven shape on the surface. Is done. In the antiglare film of the present invention, the internal haze of the light diffusing laminated resin film is 5% or more and 30% or less, and the hard coat layer has a surface haze of 0.5% or more and 15% or less. Is 2% or less.

In the antiglare film of the present invention, the relative scattered light intensity T (20) in the normal direction of the hard coat layer side when light is incident at an incident angle of 20 ° from the light diffusing laminated resin film side is 0.0001% or more. It is 0.0006% or less, and the relative scattered light intensity T (30) in the normal direction of the hard coat layer side when light is incident from the light diffusing laminated resin film side at an incident angle of 30 ° is 0.00004% or more and 0 It is preferable that it is .0002% or less. Further, when light is incident from the hard coat layer side at an incident angle of 30 °, the reflectance R (30) at a reflection angle of 30 ° is 0.05% or more and 2% or less, and the reflectance R at a reflection angle of 40 °. (40) is preferably 0.0001% or more and 0.005% or less, and the reflectance R (50) at a reflection angle of 50 ° is preferably 0.00001% or more and 0.0005% or less.

The antiglare film of the present invention may further have a low reflection film on the uneven surface of the hard coat layer.

Furthermore, according to the present invention, there is provided an antiglare polarizing plate comprising any one of the above antiglare films and a polarizing film laminated on the antiglare film. In the antiglare polarizing plate of the present invention, the polarizing film is disposed on the light diffusing laminated resin film side of the antiglare film.

The antiglare film or the antiglare polarizing plate of the present invention can be combined with an image display element such as a liquid crystal display element or a plasma display panel to form an image display device. That is, according to the present invention, the antiglare film according to any one of the above or the antiglare polarizing plate and an image display element are provided, and the antiglare film or the antiglare polarizing plate has a hard coat layer side. An image display device is provided that is disposed on the outside of the image display element on the viewing side.

According to the present invention, a light diffusing laminated resin film having a smooth transparent resin layer (B) surface and less irregularities can be obtained. Therefore, when the surface is subjected to processing such as bonding of a film or coating of a resin composition or the like, entry of bubbles into the interface or warping of the film is eliminated or reduced, thereby improving workability. be able to. In addition, defects during processing can be reduced, and changes in optical characteristics before and after processing can be minimized.

In the antiglare film and the antiglare polarizing plate of the present invention using such a light diffusing laminated resin film, the interface between the light diffusing laminated resin film and the hard coat layer and the light diffusing laminated resin film and the polarizing film Bubbles entering the interface and warping of the film can be eliminated or reduced. The antiglare film and antiglare polarizing plate of the present invention can be suitably applied to an image display device such as a liquid crystal display device.

It is a cross-sectional schematic diagram which shows the preferable example of the anti-glare film of this invention. When measuring the scattered light intensity observed in the normal direction of the hard coat layer side when light is incident from the light diffusing laminated resin film side of the antiglare film, the incident direction of light and the transmitted scattered light intensity measurement direction are determined. It is a perspective view showing typically. It is an example of the graph which plotted the relative scattered light intensity | strength (logarithmic scale) measured by changing the incident angle (phi) using the anti-glare film of this invention with respect to the incident angle. It is a figure which shows the relationship between relative scattered light intensity | strength T (20) and T (30), and contrast. It is a perspective view which shows typically the incident direction and reflection direction of the light from the hard-coat layer side when calculating | requiring a reflectance. It is an example of the graph which plotted the relationship between the reflection angle of the reflected light with respect to the light which injected at the angle of 30 degrees from the normal line of the anti-glare film of this invention, and a reflectance (a reflectance is a logarithmic scale). It is a schematic sectional drawing which shows the specific example of the metal elastic roll which can be used by this invention.

Explanation of symbols

101 light diffusing laminated resin film, 102 hard coat layer, 103 transparent resin layer (B), 104 resin layer (A), 105 light diffusing agent, 201,501 antiglare film, 202,502 normal line of antiglare film, 203 Light incident at an angle of φ from the normal, 204 Transmitted scattered light transmitted in the normal direction, 209, 509, a plane including the incident light direction and the normal of the antiglare film, 505, incident at an angle of 30 ° 506, specular reflection direction, 507, light reflected at reflection angle θ, 701a, 701b metal thin film, 702a, 702b axial roll, 703 fluid space.

<Light diffusing laminated resin film>
The light diffusing laminated resin film of the present invention comprises a transparent resin layer (B) laminated on both surfaces of a resin layer (A) made of a transparent resin in which a light diffusing agent is dispersed. As a transparent resin (hereinafter referred to as transparent resin (a)) constituting the resin layer (A) and a transparent resin (hereinafter referred to as transparent resin (b)) constituting the transparent resin layer (B) As long as it can be melted, it is not particularly limited. For example, polyvinyl chloride resin, acrylonitrile-butadiene-styrene resin, low density polyethylene resin, high density polyethylene resin, linear low density polyethylene resin, polystyrene resin, polypropylene resin, acrylonitrile Styrene resin, cellulose acetate resin, ethylene-vinyl acetate resin, acrylic-acrylonitrile-styrene resin, acrylic-chlorinated polyethylene resin, ethylene-vinyl alcohol resin, fluorine resin, methyl methacrylate resin, methyl methacrylate-styrene resin, polyacetal resin , Poly Mido resin, polyethylene terephthalate resin, aromatic polycarbonate resin, polysulfone resin, polyethersulfone resin, methylpentene resin, polyarylate resin, polybutylene terephthalate resin, resin containing alicyclic structure-containing ethylenically unsaturated monomer unit, General-purpose plastics or engineering plastics such as polyphenylene sulfide resin, polyphenylene oxide resin and polyether ether ketone resin; and polyvinyl chloride elastomer, chlorinated polyethylene, ethylene-ethyl acrylate resin, thermoplastic polyurethane elastomer, thermoplastic polyester elastomer, Ionomer resin, styrene-butadiene block polymer, ethylene-propylene rubber, polybutadiene resin and acrylic It can be mentioned rubber-like polymer such as rubber. A mixture of two or more of these may be used. Moreover, the transparent resin (a) and the transparent resin (b) may be the same or different. In the present invention, “transparency” means that the total light transmittance of a resin having a thickness of 1 mm with smooth both surfaces is 85% or more.

Among these, because of good optical properties, it is preferable to use a resin containing a methyl methacrylate resin, a styrene resin, an aromatic polycarbonate resin, and an alicyclic structure-containing ethylenically unsaturated monomer unit. it can.

The methyl methacrylate resin is a polymer containing 50% by weight or more of methyl methacrylate units. The content of methyl methacrylate units is preferably 70% by weight or more, and may be 100% by weight. The polymer having a methyl methacrylate unit of 100% by weight is a methyl methacrylate homopolymer obtained by polymerizing methyl methacrylate alone.

The methyl methacrylate resin may be a copolymer of methyl methacrylate and a monomer copolymerizable therewith. Monomers that can be copolymerized with methyl methacrylate include, for example, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, and 2-hydroxyethyl methacrylate. Methacrylic acid esters other than methyl methacrylate; acrylic acid such as methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate and 2-hydroxyethyl acrylate Esters; unsaturated acids such as methacrylic acid and acrylic acid; halogenated styrenes such as chlorostyrene and bromostyrene; alkyls such as vinyltoluene and α-methylstyrene Substituted styrenes such as Ren like; acrylonitrile, methacrylonitrile, maleic anhydride, phenyl maleimide and cyclohexyl maleimide. These monomers may be used alone or in combination of two or more.

The styrene resin is a polymer containing 50% by weight or more of a styrene monofunctional monomer unit, and may be a homopolymer of a styrene monofunctional monomer or a styrene monofunctional monomer. And a copolymer of a monofunctional monomer copolymerizable therewith. The styrene monofunctional monomer is a compound having a styrene skeleton and one double bond capable of radical polymerization in the molecule. Examples of the styrene monofunctional monomer include styrene; halogenated styrenes such as chlorostyrene and bromostyrene; substituted styrenes such as alkyl styrenes such as vinyltoluene and α-methylstyrene.

A monofunctional monomer copolymerizable with a styrene monofunctional monomer is a compound copolymerizable with a styrene monofunctional monomer having one radical-polymerizable double bond in the molecule. Examples of the monofunctional monomer copolymerizable with the styrenic monofunctional monomer include methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate. And methacrylates such as 2-hydroxyethyl methacrylate; methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, and 2-hydroxyethyl acrylate And acrylonitrile and the like, and methacrylic esters such as methyl methacrylate are preferably used. These monofunctional monomers are used alone or in combination of two or more.

The aromatic polycarbonate resin is usually a resin obtained by reacting a dihydric phenol and a carbonate precursor by an interfacial polycondensation method or a melt transesterification method; a resin obtained by polymerizing a carbonate prepolymer by a solid phase transesterification method Or a resin obtained by polymerizing a cyclic carbonate compound by a ring-opening polymerization method.

Representative examples of the dihydric phenol include hydroquinone, resorcinol, 4,4′-dihydroxydiphenyl, bis (4-hydroxyphenyl) methane, bis {(4-hydroxy-3,5-dimethyl) phenyl} methane, 1,2-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) propane (commonly called bisphenol A), 2,2 -Bis {(4-hydroxy-3-methyl) phenyl} propane, 2,2-bis {(4-hydroxy-3,5-dimethyl) phenyl} propane, 2,2-bis {(4-hydroxy-3, 5-dibromo) phenyl} propane, 2,2-bis {(3-isopropyl-4-hydroxy) phenyl} propane, 2,2-bis { 4-hydroxy-3-phenyl) phenyl} propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -3-methylbutane, 2,2-bis (4-hydroxy) Phenyl) -3,3-dimethylbutane, 2,4-bis (4-hydroxyphenyl) -2-methylbutane, 2,2-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -4-isopropylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3, 3,5-trimethylcyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis {(4-hydro Cis-3-methyl) phenyl} fluorene, α, α'-bis (4-hydroxyphenyl) -o-diisopropylbenzene, α, α'-bis (4-hydroxyphenyl) -m-diisopropylbenzene, α, α ' -Bis (4-hydroxyphenyl) -p-diisopropylbenzene, 1,3-bis (4-hydroxyphenyl) -5,7-dimethyladamantane, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfoxide 4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxydiphenyl ketone, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenyl ester, and the like. These may be used independently and may use 2 or more types together.

Among them, bisphenol A, 2,2-bis {(4-hydroxy-3-methyl) phenyl} propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl)- 3-methylbutane, 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) Aromatic polycarbonate resin obtained by using at least one bisphenol selected from the group consisting of) -3,3,5-trimethylcyclohexane and α, α'-bis (4-hydroxyphenyl) -m-diisopropylbenzene In particular, an aromatic polycarbonate resin using only bisphenol A as the dihydric phenol, and 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and bisphenol A, 2,2-bis {(4-hydroxy-3-methyl) phenyl} propane and α, α'-bis An aromatic polycarbonate resin using at least one dihydric phenol selected from (4-hydroxyphenyl) -m-diisopropylbenzene is preferably used.

As the carbonate precursor, carbonyl halides, carbonate esters, haloformates, and the like are used, and specific examples include phosgene, diphenyl carbonate, and dihaloformates of dihydric phenols.

It is a feature of a resin containing an alicyclic structure-containing ethylenically unsaturated monomer unit that contains an alicyclic structure in the repeating unit of the polymer. Specific examples of the resin containing an alicyclic structure-containing ethylenically unsaturated monomer unit include a norbornene polymer and a vinyl alicyclic hydrocarbon polymer. The alicyclic structure may be contained in either the main chain or the side chain of the polymer, or may be contained in both. From the viewpoint of light transmittance, those containing an alicyclic structure in the main chain are preferred.

More specific examples of the resin containing an alicyclic structure-containing ethylenically unsaturated monomer unit include a norbornene polymer, a monocyclic olefin polymer, a cyclic conjugated diene polymer, and a vinyl alicyclic ring. And a hydrocarbon-based polymer, and hydrogenated products thereof. Among these, from the viewpoint of light transmittance, a norbornene polymer hydrogenated product, a vinyl alicyclic hydrocarbon polymer and a hydride thereof are preferable, and a norbornene polymer hydrogenated product is more preferable.

As a transparent resin (a) and a transparent resin (b), a rubber composition is added to a resin composition obtained by adding a rubber polymer to the methyl methacrylate resin or a styrene resin. It is also preferable to use a resin composition that can be obtained. The addition of the rubbery polymer makes it difficult to break during film formation, and the yield can be improved. Moreover, since it is hard to break at the time of coating and bonding, there is an advantage that handling becomes easy. The rubber-like polymer can be contained in either one or both of the transparent resin (a) and the transparent resin (b). When it is contained in either one, it is preferable to contain it in the transparent resin (a) in consideration of maintaining the strength and good surface state of the light diffusing laminated resin film. In the case where the rubber-like polymer is contained in the transparent resin (a) and / or the transparent resin (b), the amount of the rubber-like polymer added is 100 parts by weight of the methyl methacrylate resin or the styrene resin. The amount is preferably 100 parts by weight or less, more preferably 3 to 50 parts by weight. When the addition amount of the rubbery polymer exceeds 100 parts by weight with respect to 100 parts by weight of the methyl methacrylate resin or styrene resin, the rigidity of the light diffusing laminated resin film tends to be lowered.

Examples of the rubber-like polymer include an acrylic multilayer structure polymer and a graft copolymer obtained by graft-polymerizing an ethylenically unsaturated monomer to a rubber component. The acrylic multilayer structure polymer is a multilayer structure having a rubber elastic layer or an elastomer layer and a hard layer as the outermost layer. The rubber elastic layer or the elastomer layer may be, for example, 20 to 60% by weight of the whole. The acrylic multilayer structure polymer may have a structure further including a hard layer as the innermost layer.

Here, the rubber elastic layer or the elastomer layer is a layer made of an acrylic polymer having a glass transition point (Tg) of less than 25 ° C. Acrylic polymers that form a rubber elastic layer or an elastomer layer include lower alkyl acrylate, lower alkyl methacrylate, lower alkoxy acrylate, cyanoethyl acrylate, acrylamide, hydroxy lower alkyl acrylate, hydroxy lower alkyl methacrylate, acrylic acid, methacrylic acid, etc. At least one monoethylenically unsaturated monomer of allyl methacrylate, allyl acrylate, ethylene glycol dimethacrylate, butanediol dimethacrylate, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene, maleic acid Cross-linking polymerization obtained by polymerization with polyfunctional monomers such as diallyl, trimethylolpropane triacrylate, and allylcinnamate It is.

The hard layer is a layer made of an acrylic polymer having a Tg of 25 ° C. or higher. As the acrylic polymer forming the hard layer, a homopolymer of alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms, and the alkyl methacrylate as a main component, other alkyl methacrylate, alkyl acrylate, styrene, Examples thereof include a copolymer copolymerized with a copolymerizable monofunctional monomer such as substituted styrene, acrylonitrile, and methacrylonitrile. The acrylic polymer forming the hard layer may be a crosslinked polymer obtained by adding a polyfunctional monomer to the monomer and polymerizing it. Examples of such an acrylic polymer include those described in JP-B-55-27576, JP-A-6-80739, and JP-A-49-23292.

A graft copolymer obtained by graft-polymerizing an ethylenically unsaturated monomer to a rubber component contains 5 to 80% by weight of monomer units derived from the rubber component (therefore, 95% of ethylenically unsaturated monomer units are contained). It is preferably contained in an amount of about 20% by weight. Examples of rubber components include diene rubbers such as polybutadiene rubber, acrylonitrile / butadiene copolymer rubber, and styrene / butadiene copolymer rubber; acrylic rubbers such as polybutyl acrylate, polypropyl acrylate, and poly-2-ethylhexyl acrylate; and Ethylene / propylene / non-conjugated diene rubber can be used. As the rubber component, two or more components may be used. Examples of the ethylenically unsaturated monomer include styrene, acrylonitrile, and alkyl (meth) acrylate, and among them, acrylic unsaturated monomers such as acrylonitrile and alkyl (meth) acrylate are preferably used. As such graft copolymers, those described in JP-A-55-147514 and JP-B-47-9740 can be used.

As the transparent resin (a), among the above, because of high transparency, a methyl methacrylate resin, a resin composition containing a methyl methacrylate resin and a rubbery polymer, a styrene resin, A resin composition in which a rubber-like polymer is contained in a styrene resin or an aromatic polycarbonate resin can be preferably used. The transparent resin (b) includes a rubbery polymer in a methyl methacrylate resin or a methyl methacrylate resin because of the high transparency and difficulty in coloring diffused light. A resin composition, a styrene resin, an aromatic polycarbonate resin, or a resin containing an alicyclic structure-containing ethylenically unsaturated monomer unit can be preferably used. In the transparent resin (a) and the transparent resin (b), only one kind of resin among these preferable resins may be used, or two or more kinds may be used in combination.

Next, the light diffusing agent dispersed in the resin layer (A) will be described. In the present invention, for the light diffusing agent, inorganic or organic transparent particles having a refractive index different from that of the transparent resin (a) are used in order to impart a light diffusing function to the resin layer (A). Specific examples of the light diffusing agent include calcium carbonate, barium sulfate, titanium oxide, aluminum hydroxide, silica, glass, talc, mica, white carbon, magnesium oxide, zinc oxide, and other inorganic particles, and fatty acids in these inorganic particles. Surface-treated ones; including resin particles such as crosslinked or high molecular weight styrene resin particles, crosslinked or high molecular weight acrylic resin particles, and crosslinked siloxane resin particles. As used herein, “crosslinked” resin particles refer to resin particles having a gel fraction of 10% or more when dissolved in acetone, and “high molecular weight” resin particles are weight average molecular weights ( Mw) refers to resin particles having 500,000 to 5,000,000.

High molecular weight styrene resin particles are high molecular weight resin particles obtained by polymerizing styrene monomers, or contain 50% by weight or more of styrene monomer units, and can be radically polymerized with styrene monomers. It means high molecular weight resin particles obtained by polymerizing a monomer having one double bond in the molecule. Cross-linked styrene resin particles are cross-linked resin particles obtained by polymerizing a styrene monomer and a monomer having at least two radically polymerizable double bonds in the molecule, or styrene-based single particles. Containing at least 50% by weight of a monomer unit, a styrene monomer, a monomer having one radical polymerizable double bond in the molecule, and at least two radical polymerizable double bonds in the molecule It means a crosslinked resin particle obtained by polymerizing a monomer having the same.

The styrene monomer is styrene or a derivative thereof. Styrene derivatives include, but are not limited to, halogenated styrenes such as chlorostyrene and bromostyrene; and alkyl-substituted styrenes such as vinyltoluene and α-methylstyrene. Two or more styrenic monomers may be used in combination.

The monomer having one radically polymerizable double bond in the molecule that can constitute the crosslinked or high molecular weight styrene resin particles is not particularly limited as long as it is other than the styrene monomer component. , Methacrylates such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate and 2-hydroxyethyl methacrylate; methyl acrylate, acrylic acid Acrylic esters such as ethyl, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate and 2-hydroxyethyl acrylate; and acrylonitrile. Among these, alkyl methacrylates such as methyl methacrylate are particularly preferable. Two or more of these monomers may be used in combination.

The monomer having at least two radically polymerizable double bonds capable of constituting the crosslinked or high molecular weight styrenic resin particles in the molecule is other than a conjugated diene, and the styrenic monomer and / or There is no particular limitation as long as the polymer is copolymerizable with a monomer having one radical-polymerizable double bond in the molecule. Examples of such monomers include alkyl diol di (meth) acrylates such as 1,4-butanediol di (meth) acrylate and neopentyl glycol di (meth) acrylate; ethylene glycol di (meth) acrylate, Alkylene glycol di (meth) acrylates such as diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate and tetrapropylene glycol di (meth) acrylate; divinylbenzene and diallyl phthalate Aromatic polyfunctional compounds; (meth) acrylates of polyhydric alcohols such as trimethylolpropane tri (meth) acrylate and pentaerythritol tetra (meth) acrylate It is. Two or more of these monomers may be used in combination.

The high molecular weight acrylic resin particles are high molecular weight resin particles obtained by polymerizing an acrylic monomer, or contain 50% by weight or more of an acrylic monomer unit. It means high molecular weight resin particles obtained by polymerizing a monomer having one polymerizable double bond in the molecule. Cross-linked acrylic resin particles are cross-linked resin particles obtained by polymerizing acrylic monomers and monomers having at least two double bonds capable of radical polymerization in the molecule, or acrylic single particles. Containing at least 50% by weight of a monomer unit, an acrylic monomer, a monomer having one radical polymerizable double bond in the molecule, and at least two radical polymerizable double bonds in the molecule It means a crosslinked resin particle obtained by polymerizing a monomer having the same.

Examples of the acrylic monomer include methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl methacrylate, methyl acrylate, Examples include ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, methacrylic acid, and acrylic acid. Two or more of these monomers may be used in combination.

The monomer having one radical polymerizable double bond in the molecule that can constitute the crosslinked or high molecular weight acrylic resin particles is not particularly limited as long as it is other than the acrylic monomer component. For example, styrene and its derivatives can be mentioned. Examples of the styrene derivative include halogenated styrene such as chlorostyrene and bromostyrene; alkyl-substituted styrene such as vinyltoluene and α-methylstyrene. Of these, styrene is particularly preferable. Two or more of these monomers may be used in combination.

The monomer having at least two radically polymerizable double bonds capable of constituting the crosslinked or high molecular weight acrylic resin particles in the molecule is other than a conjugated diene, and the acrylic monomer and / or The polymer is not particularly limited as long as it is a polymer copolymerizable with a monomer having one radical-polymerizable double bond in the molecule, and the above-described monomers can be given as specific examples.

Both crosslinked or high molecular weight styrene resin particles and acrylic resin particles can be obtained by polymerizing the above components by a method such as a suspension polymerization method, a micro suspension polymerization method, an emulsion polymerization method, or a dispersion polymerization method. it can.

The crosslinked siloxane-based resin (crosslinked siloxane-based polymer) constituting the crosslinked siloxane resin particles is generally referred to as silicone rubber or silicone resin and is solid at room temperature. Siloxane polymers are produced mainly by hydrolysis and condensation of chlorosilanes. For example, a (crosslinked) siloxane-based polymer can be obtained by hydrolyzing and condensing chlorosilanes represented by dimethyldichlorosilane, diphenyldichlorosilane, phenylmethyldichlorosilane, methyltrichlorosilane, and phenyltrichlorosilane. Further, the siloxane polymers are obtained by converting these (crosslinked) siloxane polymers into benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, p-chlorobenzoyl peroxide, dicumyl peroxide, di-toxide peroxide. -Crosslinking with peroxides such as butyl, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, or introducing silanol groups at the end of polysiloxane compounds, condensation crosslinking with alkoxysilanes Can also be manufactured. Examples of the crosslinked siloxane-based resin preferably used in the present invention include a crosslinked siloxane-based polymer in which 2 to 3 organic groups are bonded per silicon atom.

In order to form the crosslinked siloxane-based resin in the form of particles, a method of mechanically pulverizing the above-mentioned crosslinked siloxane-based polymer, as described in JP-A-59-68333, a specific linear organosiloxane block is used. A method for obtaining spherical particles by curing a curable polymer or a curable polymer composition contained therein in a sprayed state, and a specific alkyltrialkoxysilane or a compound thereof as described in JP-A-60-13813 A method of hydrolyzing and condensing the partially hydrolyzed condensate in an aqueous solution of ammonia or amines to form spherical particles can be used.

The refractive index of the light diffusing agent used in the present invention is preferably such that the absolute value R of the difference from the refractive index of the transparent resin (a) as the substrate is 0.01 to 0.13, A more preferred range is 01 to 0.05. This is because when R is within this range, the balance between light transmittance and light diffusibility is improved. Therefore, it is preferable to select a combination of the constituent materials of the transparent resin (a) and the light diffusing agent so that R is within this range.

The refractive index of the crosslinked or high molecular weight styrene resin particles varies depending on the constituent components of the styrene polymer constituting the crosslinked or high molecular weight styrene resin particles, but is usually about 1.53 to 1.61. Generally, the refractive index tends to increase as the content of the monomer having a phenyl group increases or as the amount of halogenated monomer increases. The refractive index of the crosslinked or high molecular weight acrylic resin particles varies depending on the constituent components of the acrylic polymer constituting the crosslinked polymer resin particles, but is usually about 1.46 to 1.55. In the case of the acrylic resin particles, generally, the refractive index tends to increase as the content of the monomer having a phenyl group increases and as the amount of the halogenated monomer increases. The refractive index of the crosslinked siloxane-based resin particles varies depending on the constituent components of the crosslinked siloxane-based polymer constituting the crosslinked siloxane-based resin particles, but is usually about 1.40 to 1.47. In general, the higher the phenyl group content in the crosslinked siloxane-based polymer and the more organic groups directly connected to silicon atoms, the higher the refractive index.

The particle size of the light diffusing agent used in the present invention is 1 to 20 μm in weight average, and preferably 2 to 15 μm. If the weight average particle diameter is less than 1 μm, the see-through tends to occur. Moreover, when a weight average particle diameter exceeds 20 micrometers, there exists a tendency for the surface smoothness of the transparent resin layer (B) in a light diffusable laminated resin film to become inadequate. That is, when a light diffusing agent having a weight average particle diameter of more than 20 μm is used for the resin layer (A), the transparent resin formed on the resin layer (A) is affected by the uneven surface shape of the resin layer (A). The smoothness of the surface of the layer (B) (the surface opposite to the resin layer (A) side) is lowered, and the transparent resin layer (B) is appropriately bonded to the surface or subjected to processing such as coating. As a result, there is a case where sufficient characteristics cannot be imparted by the processing.

The amount of the light diffusing agent contained in the resin layer (A) is preferably 5 to 40 parts by weight with respect to 100 parts by weight of the transparent resin (a) that is the base material of the resin layer (A). The amount is more preferably 5 to 30 parts by weight, still more preferably 7 to 20 parts by weight. When the amount of the light diffusing agent is less than 5 parts by weight with respect to 100 parts by weight of the transparent resin (a), the transparency tends to occur. When the amount of the light diffusing agent exceeds 40 parts by weight with respect to 100 parts by weight of the transparent resin (a), the surface smoothness of the transparent resin layer (B) in the light diffusing laminated resin film is similar to the above. It tends to be insufficient, and the resin layer (A) tends to become brittle and difficult to process.

As a method of dispersing the light diffusing agent in the transparent resin (a), a general method can be adopted, for example, a method of adding the transparent resin (a) and the light diffusing agent to an extruder, and melt-kneading, etc. Can be used. In addition to the light diffusing agent, a UV absorber, an antioxidant, a flame retardant, and a colorant such as a dye and a pigment may be added to the resin layer (A). Moreover, you may add the same additive as a resin layer (A) also about a transparent resin layer (B), unless the transparency and surface smoothness are impaired.

The light diffusing laminated resin film of the present invention includes the resin layer (A) having the above-described configuration and a transparent resin layer (B) laminated on both surfaces of the resin layer (A). By adopting a three-layer structure in which the first transparent resin layer (B), the resin layer (A), and the second transparent resin layer (B) are arranged in this order, one surface of the resin layer (A) The unevenness is filled with the second transparent resin layer (B), whereby the surface of the first transparent resin layer (B) in which the unevenness is laminated on the other surface (the resin layer (A) side is Therefore, it is possible to obtain a film having a smooth surface of the transparent resin layer (B) as compared with the case where the transparent resin layer (B) is disposed only on one side.

The thickness of the light diffusing laminated resin film of the present invention is 30 to 500 μm, preferably 40 to 200 μm, more preferably 50 to 150 μm. If the thickness is less than 30 μm, the surface smoothness of the transparent resin layer (B) tends to be lost, and if it exceeds 500 μm, it becomes difficult to handle as a film.

In the present invention, the ratio of the thickness of the resin layer (A) in the thickness of the light diffusing laminated resin film is 5% or more and less than 50%, preferably 10% or more and less than 50%, more preferably 30. % Or more and less than 50%. By controlling the thickness of the resin layer (A) in such a range, the transparent resin layer (B) is excellent in surface smoothness on the surface of the light diffusing laminated resin film (that is, the surface of the transparent resin layer (B)). It can have a thickness sufficient to impart properties. When the thickness of the resin layer (A) becomes thick enough to account for 50% or more of the thickness of the light diffusable laminated resin film, when the light diffusable laminated resin film is produced by coextrusion, the transparent resin layer (B) The surface of the surface follows the surface unevenness of the resin layer (A) to generate unevenness and cannot exhibit sufficient smoothness. In addition, if the thickness of the resin layer (A) is less than 5% of the light diffusing laminated resin film, sufficient light diffusibility cannot be exhibited while keeping the thickness of the entire light diffusing laminated resin film within a suitable range. There's a problem.

In the light diffusing laminated resin film of the present invention, in at least one of the transparent resin layer (B), the surface opposite to the resin layer (A) side, an arithmetic mean roughness R _a in conformity to JIS B0601-2001 is 0 to 0.5 μm is preferable. By transparent resin layer (B) arithmetic mean roughness R _a of the surface within this range, the workability of the surface becomes better, processability (in particular, light scattering characteristics) optical properties before and after the change in Can be further reduced. Further, it is more preferable that the _Ra value of the surfaces of the transparent resin layers (B) on both sides is 0 to 0.5 μm. Thereby, both of a light diffusable laminated film can be utilized effectively.

In addition, the maximum roughness (R _z ) according to JIS B0601-2001 of the surface on the side opposite to the resin layer (A) side in at least one transparent resin layer (B) is 0 to 2.5 μm. it is preferred, the ratio R _a of _{_{_{R z (R z / R a}}} ) is more preferably in the range of 1-5. By setting the maximum roughness (R _z ) in such a range, the unevenness of the unevenness is reduced, so that processing of the surface of the transparent resin layer (B) (for example, resin coating or film bonding) Etc.) can be more effectively suppressed.

Next, a method for producing the light diffusing laminated resin film of the present invention will be described. A coextrusion molding method is used for the production of the light diffusing laminated resin film of the present invention. That is, the constituent components of the resin layer (A) (transparent resin (a), light diffusing agent and additives added as necessary) and the constituent components of the transparent resin layer (B) (transparent resin (b) and Additives added as necessary) are respectively put into different extruders, heated and melt-kneaded and extruded from a die for coextrusion molding, thereby corresponding to the resin layer (A). A laminated film in which the resin film and the resin film corresponding to the transparent resin layer (B) are laminated and integrated is formed. The laminated film after coextrusion molding is cooled by sandwiching it between cooling rolls of a roll unit (molding roll device), and the thickness of the resulting light-diffusing laminated resin film and the thickness of the resin layer (A) are light diffusion. The light diffusing laminated resin film can be obtained by molding so that the proportion of the thickness of the diffusing laminated resin film is within the above range. As the extruder, a single screw extruder, a twin screw extruder, or the like can be used. As the die, a feed block die, a multi-manifold die, or the like can be used. Thus, the light diffusing laminated resin film of the present invention produced by coextrusion molding is different from the laminated resin film laminated through, for example, an adhesive or a pressure-sensitive adhesive, and one of the resin layers (A). The surface, the surface of the transparent resin layer (B), the other surface of the resin layer (A), and the surface of the transparent resin layer (B) are laminated in direct contact.

Here, in the present invention, an elastic roll is used as at least one of the cooling rolls sandwiching the laminated film. At least one side of transparent resin is formed by sandwiching a co-extruded laminated film between cooling rolls, at least one of which is an elastic roll, and forming by pressing at least one side of the laminated film in contact with the elastic roll. A light diffusing laminated resin film excellent in surface smoothness of the layer (B) can be obtained. If both cooling rolls sandwiching the laminated film are elastic rolls, it is possible to obtain a light diffusing laminated resin film excellent in surface smoothness of the transparent resin layers (B) on both sides. According to the present invention, it is possible to obtain a light diffusing laminated resin film in which the arithmetic average roughness _Ra and the maximum roughness _{Rz of} the transparent resin layer (B) surface are controlled within the above ranges, For example, it is possible to suppress or prevent the generation of a relatively large recess having an order of several hundred μm in diameter. Such relatively large dents that can be formed on the surface of the transparent resin layer (B) may not be evaluated by the measurement of the arithmetic average roughness _Ra and the maximum roughness _Rz . For example, it is possible to confirm using a confocal microscope or visually.

As the elastic roll, for example, a conventionally known roll such as a metal elastic roll described in Japanese Patent No. 3194904 can be used. FIG. 7 is a schematic cross-sectional view showing a specific example of a metal elastic roll that can be used in the present invention. The metal elastic roll in FIG. 7A includes a metal (for example, stainless steel, etc.) thin film 701a that forms the outer periphery of the roll, and a shaft roll 702a disposed at the axial center of the metal thin film 701a. In addition, a fluid space 703 is formed between the metal thin film 701a and the shaft roll 702a for circulating a fluid such as water or oil. The metal elastic roll of FIG. 7B includes a metal (for example, stainless steel) thin film 701b that forms the outer periphery of the roll, and a shaft roll 702b that is formed in contact with the inner periphery of the metal thin film 701a. Is provided. In this case, the shaft roll 702b is made of an elastic material such as a rubber roll. Since the outer peripheral portion (metal thin film) of such a metal elastic roll is in contact with a space for circulating a fluid or a shaft roll made of a relatively soft material, it can be elastically deformed.

Also, the configuration of the roll unit itself may be a conventionally known one. For example, the roll unit may consist of two cooling rolls arranged in a row, may consist of three cooling rolls arranged in a row, or may be an inverted L-shape. It may consist of three or more cooling rolls arranged. When the roll unit is composed of three or more cooling rolls, at least one of a pair of cooling rolls that cools and molds the coextruded laminated film first is an elastic roll. The elastic roll preferably has a mirror-finished surface (surface that contacts the laminated film). Thereby, the surface smoothness of a transparent resin layer (B) can be improved more.

<Anti-glare film>
One suitable application of the light diffusing laminated resin film of the present invention is application to an antiglare film. FIG. 1 is a schematic cross-sectional view showing a preferred example of the antiglare film of the present invention. The antiglare film shown in FIG. 1 includes a light diffusing laminated resin film 101 and a hard coat layer 102 having a fine concavo-convex shape laminated on the surface of the light diffusing laminated resin film 101. The light diffusing laminated resin film 101 has a three-layer structure including two transparent resin layers (B) 103 and a resin layer (A) 104 disposed between the two transparent resin layers (B) 103. As described above, the light diffusing agent 105 is dispersed in the resin layer (A) 104. By using the light diffusing laminated resin film of the present invention, the invasion of bubbles into the interface between the light diffusing laminated resin film and the hard coat layer and the warpage of the antiglare film can be eliminated or reduced.

As shown by the above preferred examples, the antiglare film of the present invention comprises a light diffusing laminated resin film and a hard coat layer having a fine irregular surface laminated on the surface of the light diffusing laminated resin film. I have. With this configuration, the light diffusing laminated resin film is provided with an internal scattering function, while the internal scattering function is eliminated or almost eliminated from the hard coat layer, and mainly the surface reflection characteristics are imparted. This makes it possible to control the internal scattering characteristics and the reflection characteristics independently, while preventing the deterioration of visibility due to whitishness while exhibiting excellent anti-glare performance, and for high-definition image display devices. When arranged on the surface, the antiglare film can exhibit high contrast without causing glare.

The internal haze of the light diffusing laminated resin film used for the antiglare film is preferably 5% or more, more preferably 10% or more. By setting the internal haze to 5% or more, glare can be eliminated, and by setting it to 10% or more, glare can be more effectively eliminated. The internal haze of the light diffusing laminated resin film is 30% or less. If the internal haze of the light diffusing laminated resin film exceeds 30%, when applied to an image display device, the screen becomes dark as a result, and the visibility tends to be impaired. In order to ensure sufficient brightness, the internal haze is preferably 20% or less. As will be described in detail later, in the antiglare film of the present invention, since the light diffusing laminated resin film has an antiglare property due to scattering, the internal haze of the hard coat layer having a fine uneven shape is It is essentially unnecessary, and in order to independently control the internal scattering characteristics and the reflection characteristics, it is preferable that the internal haze of the hard coat layer is substantially zero.

Here, the “inner haze” of the light diffusing laminated resin film refers to bonding one surface of the light diffusing laminated resin film to a glass substrate using an optically transparent adhesive or glycerin, and then A light diffusing laminated resin film in which a triacetyl cellulose film having a haze of approximately 0 is bonded to one surface using an optically transparent adhesive or glycerin and sandwiched between the glass substrate and the triacetyl cellulose film , Defined as haze measured according to the method shown in JIS K 7136. In this way, by being sandwiched between the glass substrate and the triacetyl cellulose film, warpage of the light diffusing laminated resin film is prevented, and haze due to the surface shape of the light diffusing laminated resin film is not considered. Therefore, the internal haze of the light diffusing laminated resin film is measured.

Specifically, the internal haze of the light diffusing laminated resin film having a three-layer structure in which the light diffusing layer is sandwiched between two transparent resin layers is an optically transparent adhesive on one surface of the light diffusing laminated resin film. A glass substrate and a triacetyl cellulose are bonded to a glass substrate using an adhesive, followed by bonding a triacetyl cellulose film having a haze of almost 0 to the other surface using an optically transparent adhesive. The light diffusing laminated resin film sandwiched between the films can be measured using a haze meter in accordance with JIS K 7136 (for example, a haze meter “HM-150” manufactured by Murakami Color Research Laboratory Co., Ltd.). . The internal haze of the light diffusing laminated resin film having a two-layer structure composed of the transparent resin layer and the light diffusing layer laminated thereon is optically transparent on the surface of the light diffusing laminated resin film on the transparent resin layer side. Adhering to a glass substrate using an adhesive, followed by adhering a triacetyl cellulose film having a haze of almost 0 to the surface of the light diffusion layer using glycerin, and sandwiching the glass substrate and the triacetyl cellulose film The light diffusing laminated resin film thus obtained can be measured using a haze meter (for example, a haze meter “HM-150” manufactured by Murakami Color Research Laboratory Co., Ltd.) in accordance with JIS K 7136.

It is preferable that the hard coat layer having a fine unevenness on the surface has a surface haze of 0.5% to 15% and an internal haze of 2% or less. As described above, in the present invention, in order to control the internal scattering characteristics and the reflection characteristics independently, the internal scattering characteristics are mainly imparted to the light diffusing laminated resin film, so that the internal haze of the hard coat layer is Is 2% or less, preferably substantially 0%. When the internal haze of the hard coat layer is substantially 0%, the haze of the hard coat layer substantially consists of only the surface haze. The surface haze of the hard coat layer is preferably 15% or less from the viewpoint of suppressing whitening, and more preferably 5% or less for more effectively suppressing whitening. However, when it is less than 0.5%, the antiglare property tends not to be exhibited.

Here, the surface haze and internal haze of the hard coat layer are measured as follows. That is, first, after forming a hard coat layer on a triacetyl cellulose film having a haze of approximately 0%, the laminated film and the glass substrate are bonded with a transparent adhesive so that the triacetyl cellulose film side becomes a bonding surface. The haze is measured according to JIS K 7136. The haze corresponds to the haze of the entire hard coat layer. Next, a triacetyl cellulose film having a haze of approximately 0% is bonded to the uneven surface of the hard coat layer using glycerin, and the haze is measured again in accordance with JIS K 7136. The haze can be regarded as “internal haze” of the hard coat layer because the surface haze caused by the surface irregularities is almost canceled by the triacetyl cellulose film bonded onto the surface irregularities. Therefore, the “surface haze” of the hard coat layer is obtained from the following formula (1).
Surface haze = Overall haze-Internal haze (1)
The method for producing the hard coat layer provided with the surface irregularities satisfying the optical characteristics described above is not particularly limited. For example, a resin solution in which a filler is dispersed is applied on a light diffusing laminated resin film, and the coating film thickness is applied. The method of forming random irregularities by exposing the filler to the coating film surface by adjusting the surface, and the embossing method of transferring the irregular surface shape to a transparent resin film using a mold having surface irregularities it can.

When a hard coat layer is formed by applying a resin solution in which a filler is dispersed on a light diffusing laminated resin film, in order to make the internal haze of the hard coat layer 2% or less, preferably about 0% From the amorphous silica primary particles, the ratio of the refractive index of the filler to the refractive index of the resin (hard coat resin) serving as the base material of the hard coat layer is about 1, or smaller than the wavelength of visible light (about 100 nm or less). The surface irregularities may be formed by dispersing the porous silica secondary particles to be dispersed in the hard coat resin. When the former method is used, the hard coat resin often exhibits a refractive index of around 1.50. Therefore, polymethyl methacrylate beads (refractive index 1.49) or methyl methacrylate / styrene copolymer is used as a filler. Combined resin beads (refractive index 1.50 to 1.59), polyethylene beads (refractive index 1.53), etc. may be appropriately selected and used.

As the resin (hard coat resin) for dispersing the filler, an ultraviolet curable resin, a thermosetting resin, an electron beam curable resin, or the like can be used, but an ultraviolet curable resin is preferable from the viewpoint of productivity and hardness. used. A commercially available product can be used as the ultraviolet curable resin. For example, one or more polyfunctional acrylates such as trimethylolpropane triacrylate and pentaerythritol tetraacrylate, and “Irgacure 907”, “Irgacure 184” (above, manufactured by Ciba Specialty Chemicals), “ A mixture with a photopolymerization initiator such as Lucillin TPO (manufactured by BASF) can be used as an ultraviolet curable resin. For example, in the case of using an ultraviolet curable resin, after dispersing the filler in the ultraviolet curable resin, the resin composition is applied to the light diffusing laminated resin film and irradiated with ultraviolet rays, so that the hard coat resin is applied. A hard coat layer in which filler is dispersed can be formed.

In the case of forming a hard coat layer having a fine uneven shape by an embossing method, the shape of the mold may be transferred to a transparent resin film using a mold having a fine uneven shape. The UV embossing method using an ultraviolet curable resin is preferable for the transfer to the mold-shaped film.

In the UV embossing method, an ultraviolet curable resin layer is formed on the surface of a light diffusing laminated resin film, and the ultraviolet curable resin layer is cured by pressing the ultraviolet curable resin layer against the concave and convex surface of the mold. It is transferred to the curable resin layer. Specifically, an ultraviolet curable resin is coated on the light diffusing laminated resin film, and the coated ultraviolet curable resin is in close contact with the uneven surface of the mold, from the light diffusing laminated resin film side. UV-curing resin is cured by irradiating UV light, and then the mold shape is UV-cured by peeling the light-diffusing laminated resin film on which the cured UV-curing resin layer is formed from the mold. Transfer to a functional resin. The kind of ultraviolet curable resin is not particularly limited. Further, instead of the ultraviolet curable resin, a visible light curable resin that can be cured with visible light having a wavelength longer than that of ultraviolet light may be used by appropriately selecting a photopolymerization initiator.

The thickness of the hard coat layer is not particularly limited, but is preferably 2 μm or more and 20 μm or less. If the thickness of the hard coat layer is less than 2 μm, sufficient hardness cannot be obtained and tends to be easily scratched. If the thickness is greater than 20 μm, the film tends to break or the film curls due to curing shrinkage of the hard coat layer. As a result, productivity tends to decrease.

The antiglare film of the present invention which is a laminate of the light diffusing laminated resin film and the hard coat layer as described above is a hard coat layer when light is incident at an incident angle of 20 ° from the light diffusing laminated resin film side. When the relative scattered light intensity T (20) observed in the side normal direction shows a value of 0.0001% or more and 0.0006% or less, and light is incident at an incident angle of 30 ° from the light diffusing laminated resin film side. It is preferable that the relative scattered light intensity T (30) observed in the normal direction of the hard coat layer shows a value of 0.00004% or more and 0.0002% or less. Here, when light is incident at an incident angle of 20 ° from the light diffusing laminated resin film side and when light is incident at an incident angle of 30 °, the relative scattered light intensity T (20 in the normal direction of the hard coat layer side) ) And T (30) will be described.

FIG. 2 shows a case where light is incident from the light diffusing laminated resin film side (the side opposite to the uneven surface of the hard coat layer) and the scattered light intensity is measured in the normal direction of the hard coat layer side (the uneven surface side). FIG. 3 is a perspective view schematically showing a light incident direction and a transmitted scattered light intensity measurement direction. Referring to FIG. 2, the hard coat layer side with respect to light 203 incident at an angle φ (incident angle) from normal line 202 of the antiglare film on the light diffusing laminated resin film side of antiglare film 201 The intensity of the transmitted scattered light 204 transmitted in the direction of the normal 202 is measured, and a value obtained by dividing the transmitted scattered light intensity by the light intensity of the light source is defined as a relative scattered light intensity T (φ). That is, when light 203 is incident at an angle of 20 ° from the normal line of the antiglare film on the light diffusing laminated resin film side of the antiglare film 201, transmission scattering observed in the direction of the hard coat layer side normal line 202 A value obtained by dividing the intensity of the light 204 by the light intensity of the light source is T (20). On the light diffusing laminated resin film side of the antiglare film 201, the light 203 is incident at an angle of 30 ° from the normal line 202 of the antiglare film. T (30) is a value obtained by dividing the intensity of the transmitted scattered light 204 observed in the direction of the normal 202 on the hard coat layer side by the light intensity of the light source. The light 203 is incident such that the direction of the light 203 incident from the light diffusing laminated resin film side and the normal line 202 of the antiglare film are on the same plane (plane 209 in FIG. 2).

When the relative scattered light intensity T (20) at 20 ° incidence exceeds 0.0006%, when this antiglare film is applied to an image display device, the luminance during black display increases due to the scattered light. , Reduce the contrast. Further, when the relative scattered light intensity T (20) at 20 ° incidence is less than 0.0001%, the scattering effect is low, and glare occurs when applied to a high-definition image display device. Similarly, even when the relative scattered light intensity T (30) at 30 ° incidence exceeds 0.0002%, when this antiglare film is applied to an image display device, the luminance at the time of black display due to the scattered light. Increases and decreases contrast. Also, when the relative scattered light intensity T (30) at 30 ° incidence is less than 0.00004%, the scattering effect is low, and glare occurs when applied to a high-definition image display device. In particular, when the antiglare film is applied to a liquid crystal display that is not self-luminous, the effect of increasing the brightness due to scattering caused by light leakage during black display is large, and therefore the relative scattered light intensities T (20) and T (30) are high. If it exceeds the preferable range, the contrast is remarkably lowered and the visibility is impaired.

3 shows the relative scattered light intensity (logarithmic scale) measured by changing the incident angle φ from the light diffusing laminated resin film side of the antiglare film of the present invention (antiglare film 201 in FIG. 2). It is an example of the graph plotted with respect to. Such a graph representing the relationship between the incident angle and the relative scattered light intensity, or the relative scattered light intensity for each incident angle read therefrom may be referred to as a transmission scattering profile. As shown in this graph, the relative scattered light intensity has a peak at an incident angle of 0 °, and the scattered light intensity tends to decrease as the angle from the normal direction of the incident light 203 increases. Incidentally, plus (+) and minus (−) of the incident angle depends on the direction of the incident light 203 around the normal direction (0 °) and the inclination of the incident light in the plane 209 including the normal 202. It is determined. Therefore, the transmission / scattering profile usually appears symmetrically about the incident angle of 0 °. In the example of the transmission scattering profile shown in FIG. 3, the relative scattered light intensity T (0) at 0 ° incidence shows a peak at about 15%, and the relative scattered light intensity T (20) at 20 ° incidence is about The relative scattered light intensity T (30) at 0.0003% and 30 ° incidence is about 0.00006%.

In measuring the relative scattered light intensity of the antiglare film, it is necessary to accurately measure the relative scattered light intensity of 0.001% or less. Therefore, it is effective to use a detector with a wide dynamic range. As such a detector, for example, a commercially available optical power meter can be used, and an aperture is provided in front of the detector of this optical power meter so that the angle at which the antiglare film is viewed is 2 °. Measurements can be made using an angular photometer. Visible light of 380 to 780 nm can be used as incident light, and a collimated light emitted from a light source such as a halogen lamp can be used as a measurement light source, or a parallel light source using a monochromatic light source such as a laser. Higher ones may be used. Moreover, in order to prevent the curvature of a film, it is preferable to use it for a measurement, after bonding to a glass substrate so that an uneven surface may become the surface using an optically transparent adhesive.

In view of the above, the relative scattered light intensities T (20) and T (30) defined in the present invention are measured as follows. The antiglare film is bonded to a glass substrate so that the uneven surface is the surface, and parallel light from a He—Ne laser is irradiated from the direction inclined at a predetermined angle with respect to the film normal on the glass surface side. The transmitted scattered light intensity in the film normal direction is measured on the uneven surface side of the antiglare film. For the measurement of transmitted scattered light intensity, “3292 03 optical power sensor” and “3292 optical power meter” manufactured by Yokogawa Electric Corporation are used for both T (20) and T (30).

FIG. 4 is a diagram showing the relationship between the relative scattered light intensities T (20) and T (30) and the contrast. As is clear from FIG. 4, when the relative scattered light intensity T (20) exceeds 0.0006% or T (30) exceeds 0.0002%, the contrast is reduced by 10% or more, and the visibility is impaired. It turns out that there is a tendency. The contrast was measured by the following procedure. First, the polarizing plate on the back side and the display surface side is peeled off from a commercially available liquid crystal television (“LC-42GX1W” manufactured by Sharp Corporation). A polarizing plate “Sumikaran SRDB31E” manufactured by Chemical Co., Ltd. was bonded via an adhesive so that each absorption axis coincided with the absorption axis of the original polarizing plate. And the anti-glare film which has the structure similar to the anti-glare film which concerns on this invention which shows various scattered light intensity | strength was bonded through the adhesive so that an uneven surface might become the surface. Next, the liquid crystal television thus obtained was activated in a dark room, and using a luminance meter “BM5A” manufactured by Topcon Corporation, the luminance in the black display state and the white display state was measured, and the contrast was calculated. Here, the contrast is represented by the ratio of the luminance in the white display state to the luminance in the black display state.

The antiglare film of the present invention has a reflectance R (30) at a reflection angle of 30 ° of 0.05% or more and 2% or less when light is incident from the hard coat layer side at an incident angle of 30 °. The reflectance R (40) at a reflection angle of 40 ° is 0.0001% or more and 0.005% or less, and the reflectance R (50) at a reflection angle of 50 ° is 0.00001% or more and 0.0005% or less. It is preferable. By making the reflectance R (30), the reflectance R (40) and the reflectance R (50) within the above ranges, the anti-glare is more effectively suppressed while showing excellent anti-glare performance. A film is provided.

Here, the reflectance for each angle when light is incident at an incident angle of 30 ° from the hard coat layer side will be described. FIG. 5 is a perspective view schematically showing an incident direction and a reflection direction of light from the hard coat layer side with respect to the antiglare film when the reflectance is obtained. Referring to FIG. 5, the direction of the reflection angle of 30 °, that is, the regular reflection direction with respect to the light 505 incident at an angle of 30 ° from the normal line 502 of the antiglare film on the hard coat layer side of the antiglare film 501. The reflectance (that is, regular reflectance) of the reflected light to 506 is R (30). Of the light 507 reflected at an arbitrary reflection angle θ, the reflectance of reflected light at θ = 40 ° and the reflectance of reflected light at θ = 50 ° are R (40) and R (50), respectively. . Note that the direction of reflected light when measuring the reflectance (the specular reflection direction 506 and the reflection direction of the light 507 reflected at the reflection angle θ) is within the plane 509 including the direction of the incident light 505 and the normal line 502. To do.

When the regular reflectance R (30) exceeds 2%, a sufficient antiglare function cannot be obtained, and the visibility tends to decrease. On the other hand, even if the regular reflectance R (30) is too small, since it tends to cause whitening, it is preferably 0.05% or more. The regular reflectance R (30) is more preferably 1.5% or less, particularly 0.7% or less. On the other hand, if R (40) exceeds 0.005% or R (50) exceeds 0.0005%, the antiglare film is whitened and the visibility tends to be lowered. That is, for example, even when black is displayed on the display surface with an anti-glare film installed on the forefront of the display device, a whitish color occurs that picks up light from the surroundings and makes the display surface entirely white. There is a tendency. Therefore, it is preferable that R (40) and R (50) are not so large. On the other hand, R (40) is generally preferably 0.0001% or more, and R (50) is generally 0, since sufficient antiglare properties are not exhibited even if the reflectance at these angles is too small. It is preferably 0.0001% or more. R (50) is more preferably 0.0001% or less.

FIG. 6 shows the reflection of the light 507 reflected at the reflection angle θ with respect to the light 505 incident at an angle of 30 ° from the normal 502 on the hard coat layer side of the antiglare film of the present invention (antiglare film 501 in FIG. 5). It is an example of the graph which plotted the relationship between angle (theta) and a reflectance (a reflectance is a logarithmic scale). Such a graph representing the relationship between the reflection angle and the reflectance, or the reflectance for each reflection angle read therefrom may be referred to as a reflection profile. As shown in this graph, the regular reflectance R (30) is a reflectance peak with respect to the light 505 incident at 30 °, and the reflectance tends to decrease as the angle deviates from the regular reflection direction. In the example of the reflection profile shown in FIG. 6, the regular reflectance R (30) is about 0.4%, R (40) is about 0.001%, and R (50) is about 0.00003%. .

In measuring the reflectance of the antiglare film, it is necessary to accurately measure a reflectance of 0.001% or less, as with the relative scattered light intensity. Therefore, it is effective to use a detector with a wide dynamic range. As such a detector, for example, a commercially available optical power meter can be used, and an aperture is provided in front of the detector of this optical power meter so that the angle at which the antiglare film is viewed is 2 °. Measurements can be made using an angular photometer. As incident light, visible light of 380 to 780 nm can be used, and as a measurement light source, collimated light emitted from a light source such as a halogen lamp can be used, or in parallel with a monochromatic light source such as a laser. A high degree may be used. In the case of an antiglare film having a smooth and transparent back surface, reflection from the back surface of the antiglare film may affect the measured value. For example, the smooth surface of the antiglare film is adhered to a black acrylic resin plate with an adhesive or It is preferable that only the reflectance on the outermost surface of the antiglare film can be measured by optical adhesion using a liquid such as water or glycerin.

In view of the above, the reflectances R (30), R (40) and R (50) defined in the present invention are measured as follows. Irradiation of parallel light from a He—Ne laser onto a concavo-convex surface of an antiglare film from a direction inclined by 30 ° with respect to the film normal, and the angle of reflectance in a plane including the film normal and the light incident direction Measure changes. For the measurement of reflectance, both “3292 03 Optical Power Sensor” and “3292 Optical Power Meter” manufactured by Yokogawa Electric Corporation are used.

The antiglare film of the present invention may have a low reflection film on the outermost surface thereof, that is, on the uneven surface side of the hard coat layer. Even in the absence of a low reflection film, a sufficient antiglare function is exhibited, but the antiglare property can be further improved by providing a low reflection film on the outermost surface. The low reflection film can be formed by providing a layer made of a low refractive index material having a refractive index lower than that of the hard coat layer on the hard coat layer. Specific examples of such a low refractive index material include lithium fluoride (LiF), magnesium fluoride (MgF ₂ ), aluminum fluoride (AlF ₃ ), cryolite (3NaF · AlF ₃ or Na ₃ AlF _6). ) And other inorganic low-reflective materials containing acrylic resin, epoxy resin, etc .; fluorine-based or silicone-based organic compounds, thermoplastic resins, thermosetting resins, UV-curable resins, etc. An organic low reflection material can be mentioned.

<Anti-glare polarizing plate>
The antiglare film of the present invention is excellent in the antiglare effect, effectively prevents whitening, and can effectively suppress the occurrence of glare and the decrease in contrast. An image display device provided with such an antiglare film of the present invention has excellent visibility. When the image display device is a liquid crystal display, this antiglare film can be applied to the polarizing plate. That is, the polarizing plate generally has a form in which a protective film is bonded to at least one surface of a polarizing film made of a polyvinyl alcohol-based resin film in which iodine or a dichroic dye is adsorbed and oriented. By using the antiglare film of the present invention, an antiglare polarizing plate can be obtained. More specifically, an antiglare polarizing plate can be obtained by laminating the polarizing film and the antiglare film of the present invention on the light diffusing laminated resin film side of the antiglare film. In this case, the other surface of the polarizing film may be in a state where nothing is laminated, another protective film or an optical film may be laminated, and an adhesive layer for bonding to a liquid crystal cell. May be formed. Further, the antiglare film of the present invention is bonded on the light diffusing laminated resin film side on the protective film of the polarizing plate having a protective film bonded on at least one side of the polarizing film, and the antiglare polarizing plate It can also be. Furthermore, in a polarizing plate having a protective film bonded to at least one surface, a light diffusing laminated resin film is used as the protective film, and a hard coat layer is formed on the light diffusing laminated resin film, thereby providing antiglare properties. It can also be a polarizing plate.

In the antiglare polarizing plate, since a light diffusing laminated resin film having excellent surface smoothness is used, bubbles at the interface between the light diffusing laminated resin film and the polarizing film or the protective film laminated on the polarizing film are used. Intrusion and warping of the film can be eliminated or reduced.

<Image display device>
The image display device of the present invention is a combination of the antiglare film or the antiglare polarizing plate of the present invention and an image display element. Here, the image display element is typically a liquid crystal panel that includes a liquid crystal cell in which liquid crystal is sealed between upper and lower substrates and displays an image by changing the alignment state of the liquid crystal by applying a voltage. The antiglare film or the antiglare polarizing plate of the present invention can be applied to various known displays such as a display, a CRT display, and an organic EL display. In the image display device of the present invention, the antiglare film or the antiglare polarizing plate is arranged on the viewing side with respect to the image display element. Under the present circumstances, it arrange | positions so that the uneven surface of an anti-glare film or an anti-glare polarizing plate, ie, a hard-coat layer side, may become an outer side (viewing side). The image display device provided with the antiglare film or the antiglare polarizing plate of the present invention can scatter incident light due to the unevenness of the surface of the antiglare film and blur the reflected image. Gives excellent visibility.

In addition, the antiglare film or the antiglare polarizing plate of the present invention does not cause glare as seen in conventional antiglare films even when applied to a high-definition image display device, and is sufficiently reflected. Inhibition performance, whitening prevention, glare suppression, and contrast reduction suppression performance.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the examples.

[Production of light-diffusing laminated resin film]
(Production Example 1: Production of rubber-like polymer)
An acrylic multilayer polymer having a three-layer structure was produced according to the method described in the example of JP-B-55-27576. 3. A glass reaction vessel having an internal volume of 5 L was charged with 1700 g of ion-exchanged water, 0.7 g of sodium carbonate and 0.3 g of sodium persulfate, stirred under a nitrogen stream, and then Perex OT-P (manufactured by Kao Corporation). 46 g, ion-exchanged water 150 g, methyl methacrylate 150 g and allyl methacrylate 0.3 g were charged. Then, the temperature was raised to 75 ° C. and stirring was continued for 150 minutes.

Subsequently, a mixture of 689 g of butyl acrylate, 162 g of styrene and 17 g of allyl methacrylate, 0.85 g of sodium persulfate, 7.4 g of Perex OT-P and 50 g of ion-exchanged water was added over 90 minutes from another inlet, The polymerization was continued for another 90 minutes. After the completion of the polymerization, a mixture of 326 g of methyl acrylate and 14 g of ethyl acrylate and 30 g of ion-exchanged water in which 0.34 g of sodium persulfate was dissolved were added from separate ports over 30 minutes. After completion of the addition, the polymerization was completed by holding for 60 minutes. The obtained latex was put into a 0.5% aluminum chloride aqueous solution to aggregate the polymer. This was washed 5 times with warm water and then dried to obtain an acrylic multilayer polymer.

<Example 1>
As a constituent material of the resin layer (A), based on 70 parts by weight of a transparent resin 1 resin [methyl methacrylate / methyl acrylate = 96/4 (weight ratio) copolymer (refractive index 1.49)] An acrylic resin composition containing 30 parts by weight of the acrylic multilayer polymer of Production Example 1] 85 parts by weight, and methyl methacrylate / styrene / ethylene glycol dimethacrylate as a light diffusing agent = 85/10/5 (Weight ratio) 15 parts by weight of copolymer particles (refractive index 1.505, weight average particle diameter 8 μm) were mixed by a Henschel mixer, melt-kneaded by an extruder I, and supplied to a feed block. On the other hand, as a constituent material of the transparent resin layer (B), resin 2 [methyl methacrylate / methyl acrylate = 96/4 (weight ratio) copolymer (refractive index 1.49)] was melted in an extruder II. Kneaded and fed to the feed block.

Subsequently, co-extrusion molding was performed at an extrusion resin temperature of 260 ° C. so that the resin layer (A) became an intermediate layer and the transparent resin layer (B) was laminated on both sides thereof, and then the resin layers (A) were arranged in a row. A roll unit comprising metal polishing rolls (referred to as first, second, and third rolls in order) is used to sandwich the extruded laminated film between the first roll and the second roll, roll it, and By sandwiching between the roll and the third roll, a light diffusing laminated resin film consisting of three layers having a thickness of 100 μm (the thickness of the resin layer (A): 48 μm and the thickness of the transparent resin layer (B): 26 μm each). Was made. Each of the first to third rolls is a metal elastic roll as shown in FIG. 7 (b), and the metal thin film is made of polished stainless steel. Water was used as the fluid to be circulated in the roll, and the set temperature was 80 ° C. for all.

<Comparative Examples 1 to 3>
3 in the same manner as in Example 1 except that the discharge amounts of the extruder I and the extruder II were adjusted so that the thicknesses of the resin layer (A) and the transparent resin layer (B) were as shown in Table 1, respectively. A light diffusing laminated resin film composed of layers was prepared.

The configuration of the extrusion apparatus used in the above examples and comparative examples is as follows.
Extruder I: Screw diameter 65 mm, uniaxial, with vent (manufactured by Toshiba Machine Co., Ltd.).
Extruder II: Screw diameter 45 mm, uniaxial, with vent (manufactured by Hitachi Zosen).
Feed block: 2-type, 3-layer distribution (manufactured by Hitachi Zosen Corporation).
Die: T-die, lip width 1400 mm, lip interval 1 mm (manufactured by Hitachi Zosen Corporation).

[Evaluation of surface condition of light diffusing laminated resin film]
(1) Evaluation of surface roughness The surface states of the two transparent resin layers (B) of the light diffusing laminated resin films obtained in the above examples and comparative examples were visually observed. Roughness was observed on the surface of the light diffusing laminated resin film. Furthermore, the surface state of the transparent resin layer (B) was observed using a confocal microscope “PLμ2300” (manufactured by Sensofa Co., Ltd.), and the degree of roughness was evaluated according to the following criteria. The results are shown in Table 1.
A: Roughness was not confirmed.
B: Slight roughness was confirmed.
C: A lot of roughness was confirmed.

When the roughened portion of the light diffusing laminated resin film of Comparative Example 1 was observed with the confocal microscope, a dent having a depth of 1 to 2 μm and a diameter of 100 to 500 μm was present.

(2) Measurement of arithmetic average roughness _{Ra According} to JIS B0601-2001, by a surface roughness shape measuring machine (Surf Test SJ-201 manufactured by Mitutoyo Co., Ltd.) The arithmetic average roughness (R _a ) of the surface of the transparent resin layer (B) on the side that was in contact with the first roll and the surface of the transparent resin layer (B) on the side that was in contact with the second roll was cut. The measurement was performed with an off value of 0.8 mm, a reference length of 0.8 mm, and a number of sections of 5. The results are shown in Table 2.

<Example 2>
[Production and evaluation of antiglare film]
(A) Production of Embossing Die A surface of a 200 mm diameter iron roll (STKM13A by JIS) was prepared by applying copper ballad plating. The copper ballad plating was composed of a copper plating layer / a thin silver plating layer / a surface copper plating layer, and the thickness of the entire plating layer was about 200 μm. The surface of the surface copper plating layer is mirror-polished, and on the polished surface, a blasting device (manufactured by Fuji Seisakusho) is used to make zirconia beads “TZ-B125” (trade name, manufactured by Tosoh Corporation). The average particle size is 125 μm), beads are used 6 g / cm ² (the amount used per 1 cm ² of the surface area of the roll, hereinafter referred to as “blast amount”), blast pressure 0.05 MPa (gauge pressure, the same applies hereinafter), and beads are injected Blasting was performed at a distance of 600 mm from the nozzle to the metal surface (hereinafter referred to as “blasting distance”). Thereafter, using the same blasting apparatus as before, zirconia beads “TZ-SX-17” (trade name, average particle size 20 μm) manufactured by Tosoh Corporation were applied to the blasted surface with a blasting amount of 3 g / cm. ^{2. The} surface was uneven by blasting at a blasting pressure of 0.05 MPa and a blasting distance of 450 mm. Etching was performed on the obtained copper-plated iron roll having surface irregularities using a cupric chloride aqueous solution. The etching amount at that time was set to 3 μm. Thereafter, the etched surface was subjected to chrome plating to produce a metal mold. At this time, the chromium plating thickness was set to 4 μm. The obtained mold had a surface Vickers hardness of 1,000.

(B) Formation of hard coat layer having fine irregularities An ultraviolet curable resin composition in which the following components were dissolved in ethyl acetate at a solid content concentration of 60% by weight was prepared.

Pentaerythritol triacrylate 60 parts by weight Polyfunctional urethanized acrylate (reaction product of hexamethylene diisocyanate and pentaerythritol triacrylate) 40 parts by weight Next, with respect to 100 parts by weight of the solid content of the ultraviolet curable resin composition, A photopolymerization initiator “Lucillin TPO” (manufactured by BASF, chemical name: 2,4,6-trimethylbenzoyldiphenylphosphine oxide) was added in an amount of 5 parts by weight to prepare a coating solution.

This coating solution was applied onto the light diffusing laminated resin film obtained in Example 1 so that the coating thickness after drying was 8.0 μm, and dried for 1 minute in a dryer set at 80 ° C. It was. The dried film was brought into close contact with the uneven surface of the metal mold produced above with a rubber roll so that the ultraviolet curable resin composition layer was on the mold side. In this state, the ultraviolet curable resin composition layer is cured by irradiating light from a high-pressure mercury lamp with an intensity of 20 mW / cm ² from the light diffusing laminated resin film side so that the amount of light in terms of h-line is 300 mJ / cm ^2. I let you. Thereafter, the light diffusing laminated resin film is peeled from the mold together with the cured resin to obtain an antiglare film comprising a laminate of a hard coat layer (cured resin) having irregularities on the surface and the light diffusing laminated resin film. It was. The resulting antiglare film does not cause glare or whitish, and when applied to an image display device, the relative scattered light intensity T (20) that causes a decrease in contrast is 0.00027%, and T (30) is Good scattering characteristics were sufficiently low at 0.00006%.

The internal haze of the light diffusing laminated resin film of Example 1 was 14.8%. The measurement was carried out by bonding one surface of a light diffusing laminated resin film to a glass substrate using an optically transparent adhesive, and subsequently, forming a triacetyl cellulose film having a haze of almost 0 on the other surface. A light diffusing laminated resin film bonded with an optically transparent adhesive and sandwiched between the glass substrate and a triacetyl cellulose film is manufactured by Murakami Color Research Laboratory Co., Ltd. in accordance with JIS K 7136. Haze meter “HM-150” type) was used.

The surface haze and internal haze of the hard coat layer were 1.7% and 0.0%, respectively. The measurement was performed as follows. First, after forming a hard coat layer on a triacetyl cellulose film having a haze of almost 0%, the laminated film and the glass substrate are bonded with a transparent adhesive so that the triacetyl cellulose film side becomes a bonding surface. The whole haze was measured by using a haze meter “HM-150” manufactured by Murakami Color Research Laboratory Co., Ltd. in accordance with JIS K 7136. Next, a triacetyl cellulose film having a haze of almost 0 was bonded to the concavo-convex surface of the hard coat layer using glycerin, and the internal haze was measured again in accordance with JIS K7136. The surface haze was calculated based on the above formula (1).

It should be considered that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

Claims

A resin layer (A) made of a transparent resin in which a light diffusing agent having a weight average particle diameter of 1 to 20 μm is dispersed, and a transparent resin layer (B) laminated on both surfaces of the resin layer (A). A light-diffusing laminated resin film having a thickness of 30 to 500 μm,
The thickness of the resin layer (A) is 5% or more and less than 50% of the thickness of the light diffusing laminated resin film,
In a state where at least one surface of a laminated film obtained by coextrusion molding using the resin composition forming the resin layer (A) and the resin composition forming the transparent resin layer (B) is in contact with an elastic roll. A light diffusing laminated resin film formed by molding the laminated film.
The light diffusing laminated resin film according to claim 1, wherein the resin layer (A) contains 5 to 40 parts by weight of a light diffusing agent with respect to 100 parts by weight of the transparent resin.
In at least one of the transparent resin layer (B), the arithmetic mean roughness R a of the surface opposite from said resin layer (A) side, the light according to claim 1 which is 0 ~ 0.5 [mu] m Diffuse laminated resin film.
The light diffusion according to claim 1, wherein the transparent resin layer (B) side surface of the resin layer (A) is in contact with the resin layer (A) side surface of the transparent resin layer (B). Laminated resin film.
The transparent resin layer (B) is composed of a methyl methacrylate resin, a resin composition containing a rubber polymer in a methyl methacrylate resin, a styrene resin, an aromatic polycarbonate resin, an alicyclic structure-containing ethylenic unsaturated resin. The light-diffusing laminated resin film according to claim 1, comprising a resin containing a monomer unit, or a mixed resin of two or more of these.
The transparent resin is a methyl methacrylate resin, a resin composition containing a methyl methacrylate resin containing a rubbery polymer, a styrene resin, a resin composition containing a rubber polymer in a styrene resin, The light-diffusing laminated resin film according to claim 1, which is an aromatic polycarbonate resin or a mixed resin of two or more of these.
A resin layer (A) made of a transparent resin in which a light diffusing agent having a weight average particle diameter of 1 to 20 μm is dispersed, and a transparent resin layer (B) laminated on both surfaces of the resin layer (A). A method for producing a light-diffusing laminated resin film having a thickness of 30 to 500 μm,
In a state where at least one surface of a laminated film obtained by coextrusion molding using the resin composition forming the resin layer (A) and the resin composition forming the transparent resin layer (B) is in contact with an elastic roll. The manufacturing method of the light diffusable laminated resin film which has the process of shape | molding the said laminated film so that the thickness of the said resin layer (A) may be 5% or more and less than 50% of the thickness of a light diffusable laminated resin film.
The light diffusing laminated resin film (101) according to claim 1 and a hard coat layer (102) laminated on the surface of the light diffusing laminated resin film (101) having a fine uneven shape on the surface. An antiglare film comprising:
The internal haze of the light diffusing laminated resin film (101) is 5% or more and 30% or less,
The hard coat layer (102) is an antiglare film having a surface haze of 0.5% to 15% and an internal haze of 2% or less.
The relative scattered light intensity T (20) in the normal direction of the hard coat layer (102) when light is incident at an incident angle of 20 ° from the light diffusing laminated resin film (101) side is 0.0001% or more and 0 .0006% or less,
Relative scattered light intensity T (30) in the normal direction of the hard coat layer (102) when light is incident at an incident angle of 30 ° from the light diffusing laminated resin film (101) side is 0.00004% or more and 0 The antiglare film according to claim 8, which is .0002% or less.
When light is incident at an incident angle of 30 ° from the hard coat layer (102) side,
The reflectance R (30) at a reflection angle of 30 ° is 0.05% or more and 2% or less,
The reflectance R (40) at a reflection angle of 40 ° is 0.0001% or more and 0.005% or less,
The antiglare film according to claim 8, wherein the reflectance R (50) at a reflection angle of 50 ° is 0.00001% or more and 0.0005% or less.
The antiglare film according to claim 8, further comprising a low-reflection film on the uneven surface of the hard coat layer (102).
An anti-glare polarizing plate comprising the anti-glare film according to claim 8 and a polarizing film laminated on the anti-glare film,
The polarizing film is an antiglare polarizing plate disposed on the light diffusing laminated resin film (101) side of the antiglare film.
An antiglare film according to claim 8 or an antiglare polarizing plate according to claim 12, and an image display element,
The anti-glare film or the anti-glare polarizing plate is an image display device arranged on the viewing side of the image display element with the hard coat layer (102) side outside.