JP2011197677A - Anti-glare film, method for manufacturing the same, polarizing plate, and image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anti-glare film that has excellent anti-glare properties and can sufficiently suppress the occurrence of discoloration and scintillation even when used in a high definition display, and can also sufficiently suppress the formation of cracks during a polarizing element laminating process or a liquid crystal cell assembly process, and changes in anti-glare property with time.SOLUTION: The anti-glare film is provided with: a light-permeable base material; and a diffusion layer that has an uneven pattern on the surface and is formed on at least one surface of the light-permeable base material. The anti-glare film is characterized in that: a coating solution which includes a radiation-curable binder that comprises, as necessary components, organic microparticles (A) and a (meth)acrylate monomer, is coated onto at least one surface of the light-permeable base material, is dried to form a coating film, and then cured to form the diffusion layer; the organic microparticles (A) within the diffusion layer have an impregnated layer that is impregnated with the radiation curable binder; and the impregnated layer has an average thickness of 0.01-1.0 μm.

Description

The present invention relates to an antiglare film, a method for producing the antiglare film, a polarizing plate, and an image display device.

In an image display device such as a cathode ray tube display device (CRT), a liquid crystal display (LCD), a plasma display (PDP), and an electroluminescence display (ELD), an optical laminate for preventing reflection is generally provided on the outermost surface. ing. Such an anti-reflection optical laminate suppresses the reflection of an image or reduces the reflectance due to light scattering or interference.

As one of the antireflection optical laminates, an antiglare film is known in which an antiglare layer having an uneven shape is formed on the surface of a transparent substrate. This antiglare film can prevent external light from being scattered due to the uneven shape of the surface, thereby preventing a decrease in visibility due to reflection of external light or reflection of an image.

As a conventional anti-glare film, for example, a film in which an anti-glare layer is formed by coating a resin containing a filler such as silicon dioxide (silica) on the surface of a transparent substrate film is known (for example, (See Patent Documents 1 and 2).
These antiglare films are a type that forms an uneven shape on the surface of the antiglare layer by agglomeration of particles such as cohesive silica, and an organic filler having a particle size larger than the film thickness of the coating film is added to the resin. There is a type in which a concavo-convex shape is formed on the layer surface, or a type in which a concavo-convex shape is transferred by laminating a film having a concavo-convex shape on the layer surface.

Such a conventional anti-glare film is designed to obtain a light diffusing and anti-glare action by the action of the surface shape of the anti-glare layer. Although it is necessary to make it large, there is a problem that when the unevenness becomes large, the haze value (haze value) of the coating film increases and white brown is generated, and the transmission sharpness decreases accordingly.
Further, the conventional type of antiglare film has a problem that a sparkle of so-called surface glare (scintillation) is generated on the film surface, and the visibility of the display screen is lowered.

By the way, in recent years, higher definition of liquid crystal displays has been promoted. However, when a conventional antiglare film is applied to a high definition liquid crystal display, the occurrence of scintillation has become a more serious problem.
Moreover, the above-mentioned conventional anti-glare film is cracked at the interface between the translucent fine particles contained in the anti-glare layer and the translucent resin during the bonding process to the polarizing element and the liquid crystal cell assembly process. There was also the problem of doing. Further, the conventional anti-glare film has a problem that the anti-glare degree changes with time with respect to the temperature and humidity change and is inferior in moisture and heat resistance.

For example, Patent Document 3 describes an antiglare material obtained by mixing resin beads swollen 70% or more with a solvent into a binder resin.
Anti-glare film with anti-glare layer using resin beads previously swollen with such a solvent can be expected to improve adhesion at the interface between resin beads and binder resin, leading to high-definition displays Is expected to apply.
However, the anti-glare film provided with the anti-glare layer using resin beads swollen with a solvent in advance is improved in adhesion at the interface between the swollen resin beads and the binder resin in the anti-glare layer. Therefore, there was room for further improvement in adhesion and the like.
For this reason, the conventional anti-glare film prevents the interface between the resin beads and the binder resin from starting cracks at a higher level during the bonding process to the polarizing element and the liquid crystal cell assembly process. In addition, there has been a demand for further reducing reflection at the interface between the binder and the resin beads to reduce browning.

JP-A-6-18706 Japanese Patent Laid-Open No. 10-20103 JP 2005-281476 A

In view of the present situation, the present invention is excellent in antiglare properties and can sufficiently suppress the occurrence of white brown and scintillation even when applied to a high-definition display. Further, the present invention can be bonded to a polarizing element. Application of the anti-glare film, the anti-glare film, the anti-glare film, and the anti-glare film capable of sufficiently suppressing the occurrence of cracks during the process and the assembly process of the liquid crystal cell and the anti-glare property over time An object of the present invention is to provide a polarizing element and an image display device.

The present invention is an antiglare film comprising a light-transmitting substrate and a diffusion layer formed on at least one surface of the light-transmitting substrate and having a concavo-convex shape on the surface. A coating liquid containing a radiation curable binder containing organic fine particles (A) and (meth) acrylate monomers as essential components is applied onto at least one surface of the light-transmitting substrate, dried and applied. A film is formed and the coating film is cured, and the organic fine particles (A) in the diffusion layer have an impregnation layer impregnated with the radiation curable binder, and the impregnation layer has an average of Antiglare property, wherein the thickness is 0.01 to 1.0 μm, and the average particle size of the organic fine particles (A) before the impregnation layer is formed is 1.0 to 10.0 μm It is a film.

The antiglare film of the present invention preferably has a haze value change of 1.5% or less before and after a 60 ° C. × 90% RH × 1000 hour moist heat resistance test.
The diffusion layer preferably further includes fine particles (B) having an average particle size smaller than that of the organic fine particles (A).
Moreover, it is preferable that the coating liquid applied to the anti-glare film of the present invention contains at least a solvent that swells the organic fine particles (A).
When the difference between the refractive index of the radiation curable binder and the refractive index of the organic fine particles (A) and the fine particles (B) is Δ _A and Δ _B , respectively, Δ _A and Δ _B are expressed by the following formulas: It is preferable to satisfy (1).
| Δ _A | <| Δ _B | (1)
Further, when the average particle diameter of the organic fine particles (A) is D _A 1 and the average particle diameter of the organic fine particles (A) in the diffusion layer is D _A 2, the D _A 1 and D _A 2 are represented by the following formulae. It is preferable to satisfy (2).
0.01 μm <D _A 2−D _A 1 <1.0 μm (2)
The average particle diameters of the organic fine particles (A) and fine particles (B) are D _A 1 and D _B 1, respectively, and the average fine particles of the organic fine particles (A) in the diffusion layer and the fine particles (B) in the diffusion layer are used. When the diameters are D _A 2 and D _B 2, respectively, it is preferable that the D _A 1, D _B 1, D _A 2, and D _B 2 satisfy the following formula (3).
D _A 2−D _A 1> D _B 2−D _B 1 ≧ 0 (3)

In the antiglare film of the present invention, the fine particles (B) are preferably organic fine particles.
The diffusion layer preferably further contains a layered inorganic compound, and the layered inorganic compound is preferably talc.
Moreover, the said diffusion layer has a convex part in the position corresponding to the organic fine particle (A) in this diffusion layer on the surface, and this convex part has the following requirements (1), (2) And it is preferable that it is lower than the height of the convex part of the position corresponding to the said organic fine particle (C) of the surface of the diffusion layer (C) containing the organic fine particle (C) which satisfies all of (3).
Requirement (1): Requirement (2) for forming the diffusion layer (C) under the same conditions as the diffusion layer containing the organic fine particles (A) except that the organic fine particles (C) are used instead of the organic fine particles (A). The organic fine particles (C) in the diffusion layer (C) have the same average particle diameter as the organic fine particles (A) in the diffusion layer (3): The organic fine particles (C) are impregnated in the diffusion layer (C) Layer does not form

The present invention also provides a method for producing an antiglare film comprising a light transmissive substrate and a diffusion layer formed on at least one surface of the light transmissive substrate and having a concavo-convex shape on the surface. A coating solution containing a radiation curable binder containing organic fine particles (A) and (meth) acrylate monomers as essential components and a solvent is applied onto at least one surface of the light-transmitting substrate, and then dried. The radiation curable binder and / or solvent includes a component that swells the organic fine particles (A), and the organic fine particles (A) are swelled. In A), the radiation curable binder is impregnated to form an impregnated layer having a thickness of 0.01 to 1.0 μm. The average particle size before the impregnated layer is formed is 1.0. To 10.0 μm, and the above The machine fine particles (A) are prepared in advance by preparing an antiglare film with a coating solution using organic fine particles having different crosslinking degrees, and selecting and using organic fine particles that match the degree of impregnation. It is also a manufacturing method of an anti-glare film.

Moreover, this invention is a polarizing plate provided with a polarizing element, Comprising: The anti-glare film of this invention is provided on the surface of the said polarizing element, It is also a polarizing plate characterized by the above-mentioned.
The present invention is also an image display device comprising the antiglare film of the present invention or the polarizing plate of the present invention on the outermost surface.
Hereinafter, the present invention will be described in detail.

The antiglare film of the present invention has a light-transmitting substrate and a diffusion layer formed on at least one surface of the light-transmitting substrate and having an uneven shape on the surface.
The light-transmitting substrate preferably has smoothness and heat resistance and is excellent in mechanical strength. Specific examples of the material forming the light-transmitting substrate include polyester (polyethylene terephthalate, polyethylene naphthalate), cellulose triacetate, cellulose diacetate, cellulose acetate butyrate, polyamide, polyimide, polyethersulfone, polysulfone, and polypropylene. , Thermoplastic resins such as polymethylpentene, polyvinyl chloride, polyvinyl acetal, polyether ketone, polymethyl methacrylate, polycarbonate or polyurethane, preferably polyester (polyethylene terephthalate, polyethylene naphthalate), cellulose triacetate Can be mentioned.

As the light transmissive substrate, an amorphous olefin polymer (Cyclo-Olefin-Polymer: COP) film having an alicyclic structure can also be used. This is a base material in which a norbornene polymer, a monocyclic olefin polymer, a cyclic conjugated diene polymer, a vinyl alicyclic hydrocarbon polymer resin, or the like is used. ZEONEX, ZEONOR (norbornene resin) manufactured by Sumitomo Bakelite Co., Ltd., Sumilite FS-1700, JSR Co., Ltd. Arton (modified norbornene resin), Mitsui Chemicals, Inc., Appel (cyclic olefin copolymer) ), Topas (cyclic olefin copolymer) manufactured by Ticona, Optretz OZ-1000 series (alicyclic acrylic resin) manufactured by Hitachi Chemical Co., Ltd., and the like. Further, the FV series (low birefringence, low photoelastic modulus film) manufactured by Asahi Kasei Chemicals Corporation is also preferable as an alternative base material for triacetylcellulose.

The light-transmitting substrate is preferably used as a film-like body rich in flexibility of the thermoplastic resin, but depending on the usage mode in which curability is required, a plate of these thermoplastic resins should be used. It is also possible to use a glass plate.

The thickness of the light transmissive substrate is preferably 20 to 300 μm, more preferably an upper limit of 200 μm and a lower limit of 30 μm. When the light-transmitting substrate is a plate-like body, the thickness may exceed these thicknesses.
The light-transmitting substrate is called an anchor agent or primer in addition to physical treatment such as corona discharge treatment and oxidation treatment to improve adhesion when an antiglare layer is formed thereon. Application of the paint may be performed in advance.

In the antiglare film of the present invention, the diffusion layer contains organic fine particles (A) and a radiation curable binder containing (meth) acrylate monomers as essential components, preferably further contains fine particles (B), more preferably. Further, a coating liquid containing a solvent that swells the organic fine particles (A) is applied on at least one surface of the light-transmitting substrate, dried to form a coating film, and the coating film is cured. It is.
In the following description, the diffusion layer includes organic fine particles (A) and fine particles (B) unless otherwise specified.

The organic fine particles (A) have an impregnation layer impregnated with the radiation curable binder in the diffusion layer. In the following description, the organic fine particles (A) before the impregnation layer is formed are referred to as “organic fine particles (A1)”, and the organic fine particles (A) having the impregnation layer formed therein, that is, in the diffusion layer The organic fine particles (A) are referred to as “organic fine particles (A2)”.
By having the impregnation layer, the organic fine particles (A2) have extremely excellent adhesion to the cured product of the radiation curable binder (hereinafter also referred to as binder resin) of the diffusion layer. Further, the impregnation layer in the organic fine particles (A2) is formed in a state in which the radiation curable binder and the material constituting the organic fine particles (A2) are mixed, so that the transmitted light of the diffusion layer is the organic matter. It becomes possible to suitably prevent scattering at the interface between the fine particles (A2) (impregnated layer) and the binder resin.
Moreover, by having the said impregnation layer, the anti-glare film of this invention will be excellent in the stability (humidity heat resistance) with respect to the time-dependent change of the glare-proof degree with respect to a temperature / humidity change. This is presumed to be improved by the following mechanism.
That is, in anti-glare films containing organic fine particles so far, when a moisture and heat resistance test is performed, the moisture that has penetrated into the diffusion layer acts on the strain of the interface between the organic fine particles and the binder resin, and the strain increases. It is presumed that the antiglare property change (change in haze) over time was caused by causing relaxation, generation of microcracks, and the like. This strain is remarkable in organic fine particles having a large particle diameter.
However, when an impregnated layer is provided like the organic fine particles (A2) in the present invention, the strain at the interface between the organic fine particles (A2) and the binder resin is reduced. It is inferred that this is suppressed.
Furthermore, as will be described later, when the impregnation layer contains the radiation curable binder and the solvent, the radiation curable binder and / or the solvent are suitably formed by swelling the organic fine particles (A1). Since it is a layer, the organic fine particles (A2) are very flexible fine particles. For this reason, convex portions are formed on the surface of the diffusion layer at positions corresponding to the organic fine particles (A2) in the diffusion layer, but the shape of the convex portions can be made gentle. This point will be described in more detail later.

As the material constituting the organic fine particles (A1), those which are swollen by a radiation curable binder and / or a solvent described later are preferable. Specifically, for example, a polyester resin, a styrene resin, an acrylic resin, an olefin resin, Or these copolymers etc. are mentioned, Especially, a crosslinked acrylic resin is used suitably. In the present specification, “resin” is a concept including resin components such as monomers and oligomers.
Here, when the organic fine particles made of an acrylic resin, a styrene resin, and an acrylic-styrene copolymer are produced by a generally known production method, an acrylic-styrene copolymer resin may be used as a material. Further, when the organic fine particles (A1) are core-shell type fine particles, there are polystyrene fine particles using fine particles made of acrylic resin for the core, and conversely polyacryl fine particles using fine particles made of styrene resin for the core. . Therefore, in this specification, the distinction between the acrylic fine particles, the styrene fine particles, and the acrylic-styrene copolymer fine particles is determined based on which resin has the closest characteristic (for example, refractive index) to the fine particles. . For example, if the refractive index of the fine particles is less than 1.50, acrylic fine particles are obtained, and if the refractive index of the fine particles is 1.50 or more and less than 1.59, acrylic-styrene copolymer fine particles are obtained, and the refractive index of the fine particles is 1. If it is 59 or more, it can be regarded as styrene fine particles.

Examples of the cross-linked acrylic resin include acrylic monomers such as acrylic acid and acrylic acid ester, methacrylic acid and methacrylic acid ester, acrylamide and acrylonitrile, a polymerization initiator such as persulfuric acid, and a cross-linking agent such as ethylene glycol dimethacrylate. A homopolymer or a copolymer obtained by polymerization using a suspension polymerization method or the like is preferable.
As the acrylic monomer, a cross-linked acrylic resin obtained using methyl methacrylate is particularly suitable. The thickness of the impregnated layer can be controlled by adjusting the degree of swelling by the radiation curable binder and / or solvent described later. For this purpose, the amount of impregnation of the radiation curable binder is within a preferable range. It is preferable to change the degree of crosslinking.

The average particle size of the organic fine particles (A1) is preferably in the range of 0.5 to 15.0 μm, for example. In particular, the range of 1.0-10.0 micrometers is more suitable. When the particle size is less than 0.5 μm, the antiglare property of the antiglare film of the present invention may be insufficient. When it exceeds 15.0 μm, the antiglare film of the present invention is applied. The image on the display may become rough and the image quality may deteriorate.
In addition, the average particle diameter means an average particle diameter if each particle contained in the diffusion layer is a monodisperse type particle (particle having a single shape), and has a broad particle size distribution. In the case of an irregular-shaped particle having a particle size, it means the particle size of the most abundant particle by particle size distribution measurement. The particle size can be measured mainly by the Coulter counter method. In addition to this method, measurement can also be performed by laser diffraction, SEM observation, or optical microscope observation.

The organic fine particles (A2) in the diffusion layer have an impregnation layer.
The impregnation layer is a layer formed by impregnating the radiation curable binder from the outer surface of the organic fine particles (A2) in the diffusion layer toward the center thereof. The impregnated layer is a layer formed by impregnating mainly low molecular weight components, that is, monomers, in the radiation curable binder, and a polymer of radiation curable binder, which is a high molecular component, that is, a polymer or oligomer. Is difficult to impregnate.
The impregnated layer can be identified, for example, by observing a cross section of the organic fine particles (A2) in the diffusion layer with a microscope (SEM or the like).
The radiation curable binder impregnated in the impregnation layer may be impregnated with all the constituent components, or may be impregnated with a part of the constituent components.

In addition, in the anti-glare film of this invention, when the fine particle (B) mentioned later is contained in the said diffused layer, the said organic fine particle (A2) has an average particle diameter rather than the fine particle (B) in the said diffused layer. It is preferable that it is large. When the average particle size of the organic fine particles (A2) is equal to or smaller than the average particle size of the fine particles (B) in the diffusion layer, a high protrusion is formed at a position corresponding to the fine particles (B) on the surface of the diffusion layer. A part may be formed, and it may become impossible to suppress white brown.

The impregnated layer has an average thickness of 0.01 to 1.0 μm. If the thickness is less than 0.01 μm, the effect obtained by forming the above-described impregnation layer cannot be sufficiently obtained. If the thickness exceeds 1.0 μm, the internal diffusion function of the organic fine particles (A2) cannot be sufficiently exhibited, and scintillation It is not possible to obtain a sufficient prevention effect. The preferable lower limit of the average thickness of the impregnated layer is 0.1 μm, and the preferable upper limit is 0.8 μm. By being in this range, the above-mentioned effect can be exhibited more.
The average thickness of the impregnated layer means the average value of the thickness of the impregnated layer in the cross section of the organic fine particles (A) observed in the cross-sectional SEM photograph of the antiglare film. Specifically, the cross section of the diffusion layer is 3000 to 50,000 times by SEM, and after observing and photographing any five scenes in which at least one fine particle with an impregnation layer is present, The thickness can be obtained as a value obtained by measuring two points for each fine particle and averaging 10 measured values. The thickness of the impregnated layer is measured by selecting two points where the boundary between the binder resin around the fine particles and the fine particles is relatively clear and the maximum impregnation is performed.

Here, the organic fine particles generally have a crosslinked structure, but the degree of swelling due to the radiation curable binder or solvent varies depending on the degree of crosslinking, and usually the degree of swelling decreases as the degree of crosslinking increases. When the degree of crosslinking is low, the degree of swelling increases. Therefore, for example, when the material constituting the organic fine particles (A2) is the above-mentioned crosslinked acrylic resin, the thickness of the impregnated layer can be set to a desired range by appropriately adjusting the degree of crosslinking of the crosslinked acrylic resin. Can be controlled.

The antiglare film of the present invention has the following formula when the average particle size of the organic fine particles (A1) is D _A 1 and the average particle size of the organic fine particles (A2) in the diffusion layer is D _A 2. It is preferable to satisfy (2).
0.01 μm <D _A 2−D _A 1 <1.0 μm (2)
In the above formula (2), if “D _A 2 -D _A 1” is less than 0.01 μm, the thickness of the impregnated layer becomes too thin, and the effect obtained by forming the above impregnated layer is obtained. There are times when you can't. When “D _A 2 -D _A 1” exceeds 1.0 μm, the internal diffusion function may not be sufficiently exhibited, and the scintillation preventing effect may not be sufficiently obtained.
The more preferable lower limit of the “D _A 2-D _A 1” is 0.1 μm, and the more preferable upper limit is 0.5 μm. By having “D _A 2 -D _A 1” in this range, the above-described effects can be more exhibited.

In the antiglare film of the present invention, as the organic fine particles (A1), for example, an antiglare film is prepared in advance with a coating solution using organic fine particles having different cross-linking degrees, and matches with a preferable degree of impregnation. Organic fine particles may be selected and used.

The organic fine particles (A2) are preferably not aggregated in the diffusion layer. When the organic fine particles (A2) in the diffusion layer are aggregated, a large convex portion is formed on the surface of the diffusion layer at a position corresponding to the aggregated organic fine particles (A2), and the antiglare film of the present invention has white brown. Or scintillation may occur. In addition, aggregation of the organic fine particles (A2) in the diffusion layer can be suitably prevented by containing, for example, a layered inorganic compound described later.

Although it does not specifically limit as content of the organic fine particle (A1) in the said coating liquid, It is preferable that it is 0.5-30 mass parts with respect to 100 mass parts of radiation-curable binders mentioned later. If the amount is less than 0.5 part by mass, a sufficient uneven shape cannot be formed on the surface of the diffusion layer, and the antiglare performance of the antiglare film of the present invention may be insufficient. On the other hand, when the amount exceeds 30 parts by mass, the organic fine particles (A1) are aggregated in the coating liquid, and a large convex portion is formed on the surface of the diffusion layer, which may cause white brown or scintillation. The minimum with more preferable content of the said organic fine particle (A1) is 1.0 mass part, and a more preferable upper limit is 20 mass parts. By being in this range, the above-mentioned effect can be further ensured.

The fine particles (B) are particles that are not swollen by the radiation-curable binder and solvent in the coating liquid.
Here, “particles that are not swollen” include not only the case where they are not swollen by the radiation curable binder and the solvent, but also cases where they are slightly swollen. In the case of “slightly swelled”, an impregnation layer similar to the organic fine particles (A2) is formed on the fine particles (B) in the diffusion layer. The case is smaller than the impregnated layer of organic fine particles (A) and less than 0.1 μm. In addition, it is preferable that the fine particle (B) has a slightly impregnated layer formed from the viewpoint of suppressing the change in the antiglare degree with time.
Whether or not an impregnation layer is formed on the fine particles (B) in the diffusion layer can be determined by, for example, observing a cross section of the fine particles (B) in the diffusion layer with a microscope (SEM or the like). .
In the following description, the fine particles (B) added to the coating liquid are referred to as “fine particles (B1)”, and the fine particles (B) in the diffusion layer are referred to as “fine particles (B2)”. .

The fine particles (B1) are not particularly limited as long as they are not swollen by a radiation curable binder and a solvent. For example, inorganic particles such as silica fine particles, polystyrene resins, melamine resins, polyester resins, acrylic resins, olefin resins. Alternatively, organic particles such as these copolymers having an increased degree of crosslinking can be mentioned, and organic particles that can easily control the refractive index and particle size are preferred. These fine particles (B1) may be used alone or in combination of two or more.
Among these, since the refractive index is high and it is easy to provide a difference in refractive index from the binder (the refractive index of a normal radiation curable binder is about 1.48 to 1.54), and internal diffusion is easily obtained. Acrylic-styrene copolymer fine particles are preferably used. In the following description, it is assumed that the fine particles (B) are organic particles.
Hereinafter, the fine particles may be referred to as “highly crosslinked” or “lowly crosslinked”, and the “highly crosslinked” and “lowly crosslinked” are defined as follows.
A mixture of toluene and methyl isobutyl ketone (mass ratio 8: 2) is mixed with a radiation curable binder (a mixture of pentaerythritol triacrylate (PETA), dipentaerythritol hexaacrylate (DPHA), and polymethyl methacrylate (PMMA) ( Mass ratio: PETA / DPHA / PMMA = 86/5/9)) A coating liquid containing 190 parts by mass with respect to 100 parts by mass is prepared.
Fine particles are immersed in the resulting coating liquid for 24 hours, and fine particles in which swelling is observed are defined as “low crosslinking”, and fine particles in which swelling is not observed are defined as “high crosslinking”.

The average particle size of the fine particles (B1) is not particularly limited, but may be equal to the average particle size of the organic fine particles (A1) described above. However, when the said organic fine particle (A1) contains the said radiation-curable binder and a solvent, it swells with a radiation-curable binder and / or a solvent, and an impregnation layer is formed. Therefore, in the antiglare film of the present invention, the average particle diameters of the organic fine particles (A1) and fine particles (B1) are D _A 1 and D _B 1 respectively, and the organic fine particles (A2) and fine particles in the diffusion layer are used. When the average particle diameter of (B2) is set to D _A 2 and D _B 2, said D _A 1, D _B 1, D _A 2 and D _B 2 preferably satisfy the following formula (3).
D _A 2−D _A 1> D _B 2−D _B 1 ≧ 0 (3)
By satisfy | filling said Formula (3), while making the unevenness | corrugation of the spreading | diffusion layer surface smooth, control of internal diffusion can be made easy, and it can be made more reliable prevention of browning and scintillation.

In the antiglare film of the present invention, as the fine particles (B1), for example, an antiglare film is prepared in advance with a coating liquid using organic fine particles having different crosslinking degrees, and the organic fine particles conform to a preferable degree of impregnation. Can be selected and used.

Although it does not specifically limit as content of the organic fine particle (B1) in the said coating liquid, It is preferable that it is 0.5-30 mass parts with respect to 100 mass parts of radiation-curable binders mentioned later. If the amount is less than 0.5 parts by mass, scintillation is likely to occur. On the other hand, if it exceeds 30 parts by mass, the contrast may be lowered. The minimum with more preferable content of the said organic fine particle (B1) is 1.0 mass part, and a more preferable upper limit is 20 mass parts. By being in this range, the above-mentioned effect can be further ensured.

In the antiglare film of the present invention, the radiation curable binder contains a (meth) acrylate monomer as an essential component.
Examples of such a radiation curable binder preferably include those that swell the organic fine particles (A1) described above, and are preferably transparent. For example, an ionizing radiation curable resin that is cured by ultraviolet rays or electron beams is used. Can be mentioned. In the present specification, “(meth) acrylate” refers to methacrylate and acrylate.
Moreover, in this specification, since the monomer is ionized radiation cured to form a polymer film, it includes all molecules that can be a structural unit of the basic structure of the polymer film and has an unsaturated bond. That is, if the oligomer or prepolymer is a basic unit of a cured film, the oligomer or prepolymer is also included.
In the present invention, the monomer preferably has a small molecular weight of 5000 or less.

Examples of the (meth) acrylate monomer include compounds having one or more unsaturated bonds such as a compound having a (meth) acrylate functional group.
Examples of the compound having one unsaturated bond include ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone and the like. Examples of the compound having two or more unsaturated bonds include polymethylolpropane tri (meth) acrylate, hexanediol di (meth) acrylate, polypropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di ( Meth) acrylate, bisphenol F EO modified di (meth) acrylate, bisphenol A EO modified di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, isocyanuric acid EO modified di (meth) Acrylate, isocyanuric acid EO-modified tri (meth) acrylate, trimethylolpropane PO-modified tri (meth) acrylate, trimethylolpropane EO-modified tri (meth) acrylate Relate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, etc. Reaction products (for example, poly (meth) acrylate esters of polyhydric alcohols) such as polyfunctional compounds and (meth) allylates are included.
Moreover, the urethane (meth) acrylate and polyester (meth) acrylate which have two or more unsaturated bonds are also mentioned.

As the ionizing radiation curable resin, in addition to the above (meth) acrylate monomer, a relatively low molecular weight polyester resin having an unsaturated double bond, polyether resin, acrylic resin, epoxy resin, urethane resin, alkyd resin, spiro Acetal resin, polybutadiene resin, polythiol polyene resin, and the like can also be used as the ionizing radiation curable resin.

When the ionizing radiation curable resin is used as an ultraviolet curable resin, the coating liquid preferably contains a photopolymerization initiator.
Specific examples of the photopolymerization initiator include acetophenones, benzophenones, Michler benzoylbenzoate, α-amyloxime esters, thioxanthones, propiophenones, benzyls, benzoins, and acylphosphine oxides. It is done. In addition, it is preferable to use a mixture of photosensitizers, and specific examples thereof include n-butylamine, triethylamine, poly-n-butylphosphine, and the like.

As the photopolymerization initiator, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, etc. are used alone or in combination when the ultraviolet curable resin is a resin system having a radical polymerizable unsaturated group. It is preferable. When the ultraviolet curable resin is a resin system having a cationic polymerizable functional group, the photopolymerization initiator includes aromatic diazonium salt, aromatic sulfonium salt, aromatic iodonium salt, metallocene compound, benzoin sulfonic acid. It is preferable to use esters or the like alone or as a mixture.
It is preferable that the addition amount of the said photoinitiator is 0.1-10 mass parts with respect to 100 mass parts of ultraviolet curable resin.

In addition, the ionizing radiation curable resin is used in combination with a solvent-drying resin (a thermoplastic resin, such as a resin that forms a film only by drying a solvent added to adjust the solid content during coating). It can also be used.
Examples of the solvent-drying resin include thermoplastic resins. As the thermoplastic resin, those generally exemplified are used. By adding the solvent-drying resin, coating film defects on the coated surface can be effectively prevented.
Specific examples of preferable thermoplastic resins include, for example, styrene resins, (meth) acrylic resins, vinyl acetate resins, vinyl ether resins, halogen-containing resins, alicyclic olefin resins, polycarbonate resins, and polyester resins. , Polyamide resins, cellulose derivatives, silicone resins, and rubbers or elastomers.
As the thermoplastic resin, it is usually preferable to use a resin that is non-crystalline and soluble in an organic solvent (particularly a common solvent capable of dissolving a plurality of polymers and curable compounds). In particular, resins with high moldability or film formability, transparency and weather resistance, such as styrene resins, (meth) acrylic resins, alicyclic olefin resins, polyester resins, cellulose derivatives (cellulose esters, etc.) Etc. are preferred.

According to a preferred embodiment of the present invention, when the material of the light-transmitting substrate is a cellulose resin such as triacetyl cellulose “TAC”, as a preferred specific example of the thermoplastic resin, a cellulose resin such as nitrocellulose, Examples include acetyl cellulose, cellulose acetate propionate, and ethyl hydroxyethyl cellulose. By using the cellulose resin, the adhesion and transparency between the light-transmitting substrate and the diffusion layer can be improved.

The coating liquid may further contain a thermosetting resin. Examples of the thermosetting resin include phenol resin, urea resin, diallyl phthalate resin, melanin resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea cocondensation resin, silicon resin. And polysiloxane resin. When a thermosetting resin is used, a curing agent such as a crosslinking agent and a polymerization initiator, a polymerization accelerator, a solvent, a viscosity modifier, and the like can be used in combination as necessary.

In the antiglare film of the present invention, the refractive index of the radiation-curable binder, when the difference between the refractive index of the organic fine particles (A1) and organic fine particles (B1), and with each delta _A and delta _B, the delta _a and delta _B, it is preferable to satisfy the following formula (1).
| Δ _A | <| Δ _B | (1)
By satisfying the above formula (1), there is no scintillation having both internal diffusion with a small diffusion angle due to organic fine particles (A) and internal diffusion with a large diffusion angle due to organic fine particles (B), and excellent prevention of screen luminance uniformity. A dazzling film can be obtained.
The refractive index of the radiation curable binder, the organic fine particles (A1) and the organic fine particles (B1) can be measured by any method. For example, the Becke method, the minimum deviation method, the deviation analysis, the mode・ It can be measured by line method, ellipsometry method, etc. In addition to measuring the material itself, each method can be used in the same manner for a material in which fine particles are taken out from the film of the produced antiglare film.
Further, when the radiation curable binder contains the (meth) acrylate and other resins, the refractive index of the radiation curable binder is the refractive index of all the resin components contained excluding fine particles. Say.

The solvent is not particularly limited. For example, water, alcohol (eg, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketone (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclopentanone), ester ( Examples, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate), aliphatic hydrocarbons (eg, hexane, cyclohexane), halogenated hydrocarbons (eg, methylene chloride, chloroform) , Carbon tetrachloride), aromatic hydrocarbons (eg, benzene, toluene, xylene), amides (eg, dimethylformamide, dimethylacetamide, n-methylpyrrolidone), ethers (eg, diethyl ether, dioxane, tetrahydrophenol) Emissions), ether alcohols (e.g., 1-methoxy-2-propanol) and the like.

The radiation curable binder and the solvent may both be selected from those having the property of swelling the organic fine particles (A1), but only one of them has the property of swelling the organic fine particles (A1). You may select and use.
In addition, the formation of the impregnated layer of the organic fine particles (A1) is more reliable regardless of the degree of swelling of the radiation curable binder by the presence of a solvent having a property of swelling the organic fine particles (A1). Therefore, it is more preferable that at least the solvent has a property of swelling the organic fine particles (A1). It is presumed that this is because the organic fine particles (A1) are first swelled by the action of the solvent, and then the organic fine particles (A1) are swelled and then impregnated with the low molecular weight components contained in the radiation curable binder. is doing.
In the antiglare film of the present invention, the combination of the radiation curable binder and the solvent is a (meth) acrylate monomer and the organic solvent as the solvent because the molecular weight is small and the impregnation is easy. It is preferable to use a combination of a strong ketone and ester type which swell the fine particles (A1).
Moreover, the amount of impregnation of the low molecular weight component contained in the radiation curable binder can be controlled by adjusting the degree of swelling of the organic fine particles (A1) by mixing and using the solvent.

The coating solution preferably further contains a layered inorganic compound. The diffusion layer to be formed contains the above-mentioned layered inorganic compound, and impact resistance such as curl prevention, ultraviolet resistance, crack prevention and the like of the diffusion layer can be improved.
The layered inorganic compound is not particularly limited, and montmorillonite, beidellite, nontronite, saponite, hectorite, soconite, stevensite, vermiculite, halloysite, kaolinite, endellite, dickite, talc, pyrophyllite, mica, margarite , Muscovite, phlogopite, tetrasilic mica, teniolite, antigolite, chlorite, cookite, and nanthite. These layered inorganic compounds may be natural products or synthetic products.

As the layered inorganic compound, talc is particularly preferable. For example, when talc is used as the layered inorganic compound, crosslinked acrylic beads are used as the organic fine particles (A1), and styrene is used as the organic fine particles (B1), the organic fine particles (A2) and the organic fine particles (B2) in the diffusion layer are used. It is possible to suitably control the degree of aggregation. As a result, the antiglare film obtained can be achieved at a high level of antiglare property, white-brown prevention property, and scintillation prevention property.
This is presumed to be due to the fact that the talc is a highly lipophilic substance. That is, the organic fine particles (A1) (cross-linked acrylic resin) have hydrophilic properties, the organic fine particles (B1) (styrene) have lipophilic properties, and both fine particles are aggregated by the highly lipophilic talc. I guess that.

The content of the layered inorganic compound in the coating solution is preferably 2 to 40 parts by mass with respect to 100 parts by mass of the radiation curable binder. When the amount is less than 2 parts by mass, the impact resistance of the antiglare film of the present invention and / or dispersibility of organic fine particles (A2) and the like may be insufficient. In some cases, the viscosity of the coating liquid that forms the film becomes so high that coating cannot be performed, and the unevenness of the surface of the coating film to be formed cannot be controlled. The minimum with more preferable content of the said layered inorganic compound is 4 mass parts, and a more preferable upper limit is 30 mass parts. By being in this range, the effect of impact resistance and / or fine particle dispersibility can be more exerted, and the control of surface irregularities becomes easier.

The said coating liquid can be prepared by mixing each material mentioned above.
A method for preparing the coating liquid by mixing the above materials is not particularly limited, and for example, a paint shaker or a bead mill may be used.

The said diffusion layer can be formed by apply | coating the said coating liquid on the at least one surface of the said translucent base material, drying, forming a coating film, and hardening this coating film.
The method for applying the coating liquid is not particularly limited, and examples thereof include a roll coating method, a Miya bar coating method, a gravure coating, and a die coating method.

The thickness of the coating film formed by applying the coating liquid is not particularly limited, and is appropriately determined in consideration of the desired thickness of the diffusion layer, the uneven shape formed on the surface, the material to be used, and the like. Preferably, it is about 1-20 micrometers, 2-15 micrometers is more preferable, and 2-10 micrometers is further more preferable.

As described above, the organic fine particles (A2) are prepared by swelling the organic fine particles (A1) with the radiation curable binder and / or solvent and impregnating the radiation curable binder to form an impregnated layer. However, the preparation of the organic fine particles (A2) may be performed in the coating solution or in a coating film formed by coating on the light-transmitting substrate.

Furthermore, it is preferable that the prepared coating liquid is allowed to stand for a predetermined time before forming the diffusion layer.
When a diffusion layer is formed without preparing and leaving the coating solution, the degree of crosslinking of the organic fine particles (A) used and the degree of swelling of the organic fine particles (A) by the radiation curable binder and / or solvent are determined. This is because even if adjusted appropriately, it may not be possible to form a sufficient impregnation layer on the organic fine particles (A2) in the diffusion layer.
The standing time of the coating liquid may be appropriately adjusted according to the type of organic fine particles (A) to be used, the degree of crosslinking and the particle size, and the type of radiation curable binder and / or solvent to be used. It is preferable that it is about -48 hours.

After the coating film formed on the light transmissive substrate is dried as necessary, the diffusion layer can be formed by curing.
Although it does not specifically limit as a hardening method of the said coating film, It is preferable to carry out by ultraviolet irradiation. When curing by ultraviolet rays, it is preferable to use ultraviolet rays having a wavelength range of 190 to 380 nm. Curing with ultraviolet rays can be performed, for example, with a metal halide lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, or the like. Specific examples of the electron beam source include various electron beam accelerators such as a cockcroft-wald type, a bandegraft type, a resonant transformer type, an insulating core transformer type, a linear type, a dynamitron type, and a high frequency type.

In the antiglare film of the present invention, the diffusion layer has an uneven shape on the surface.
The diffusion layer preferably has a convex portion (hereinafter also referred to as a convex portion (A)) at a position corresponding to the organic fine particles (A) in the diffusion layer, and the convex portion (A) has a height thereof. , Convex portions at positions corresponding to the organic fine particles (C) on the surface of the diffusion layer (C) containing the organic fine particles (C) satisfying all of the following requirements (1), (2) and (3) (hereinafter, It is preferably lower than the height of the convex part (C).
Requirement (1): Requirement (2) for forming the diffusion layer (C) under the same conditions as the diffusion layer containing the organic fine particles (A) except that the organic fine particles (C) are used instead of the organic fine particles (A). The organic fine particles (C) in the diffusion layer (C) have the same average particle diameter as the organic fine particles (A) in the diffusion layer (3): The organic fine particles (C) are impregnated in the diffusion layer (C) Layer does not form

The said convex part (A) is low compared with the said convex part (C), and is a gentle shape. The antiglare film of the present invention having a diffusion layer having such a convex part (A) can be excellent in antiglare property and anti-glare property.
This is because the organic fine particles (A) when the coating film is cured are the organic fine particles (A2) on which the above-mentioned impregnation layer is formed, and the organic fine particles (A2) are compared with the organic fine particles (C). And it is taken because it is a very flexible fine particle. That is, when the coating film is cured, the radiation curable binder causes curing shrinkage, but the curing shrinkage of the surface where the organic fine particles (A2) are located is the shrinkage of the surface where the organic fine particles (A) are not located. In comparison, the amount of the radiation curable binder is small, so it becomes small. However, since the organic fine particles (A2) are very flexible fine particles, the organic fine particles (A) are deformed by curing shrinkage of the coating film. As a result, the height of the convex portion (A) formed is lower and smoother than the convex portion (C) formed on the surface of the diffusion layer (C) containing the harder organic fine particles (C). I guess it will be.
The height of the convex portion means that the surface of the antiglare film is observed by AFM, and the inflection point that changes from the convex portion to the concave portion on the slope of the convex portion existing on the surface, to the apex of the convex portion. Means an average value measured at 10 points (arbitrary).

Since the antiglare film of the present invention has the above-mentioned diffusion layer, the adhesion between the organic fine particles (A) in the diffusion layer and the cured product of the radiation curable binder is extremely excellent. In addition, it is preferable that the anti-glare film of the present invention does not cause cracks in a mandrel test under the condition that the mandrel diameter is 10 mm, more preferably 8 mm, and even more preferably 6 mm.
The organic fine particles (A) in the diffusion layer are formed with the above-mentioned impregnation layer, and the impregnation layer is formed in a state in which a radiation curable binder is mixed. Appropriate internal diffusivity can be exhibited while suitably preventing the light transmitted through the diffusion layer from being scattered at the interface between the organic fine particles (A) (impregnated layer) and the cured product of the radiation curable binder. it can.
Furthermore, the convex part formed in the position corresponding to the organic fine particles (A) of the diffusion layer can be formed into a gentle shape with a low height.
Therefore, the antiglare property, the anti-glare property and the scintillation property of the antiglare film of the present invention can be achieved at a high level.

The antiglare film of the present invention preferably has a haze value change of 1.5% or less before and after a 60 ° C. × 90% RH × 1000 hour moist heat resistance test. If it exceeds 1.5%, the anti-glare property is inferior to the temperature and humidity change due to poor heat and humidity resistance. The change in the haze value is more preferably 1.0% or less. Such moisture and heat resistance can be obtained by containing the organic fine particles (A) on which the above-described impregnation layer is formed in the diffusion layer.
In addition, the said haze value is the value measured using haze meter HR100 (Murakami Color Research Laboratory company make, brand name) according to the haze (cloudiness) prescribed | regulated to JIS-K7136.

The method for producing such an antiglare film of the present invention is also one of the present invention.
That is, the method for producing an antiglare film of the present invention includes an antiglare film having a light-transmitting substrate and a diffusion layer formed on at least one surface of the light-transmitting substrate and having an uneven shape on the surface. A coating liquid comprising a radiation curable binder and a solvent containing organic fine particles (A) and (meth) acrylate monomers as essential components on at least one surface of the light transmissive substrate. And drying to form a coating film, curing the coating film, and forming the diffusion layer. The radiation curable binder and / or solvent swell the organic fine particles (A). The organic fine particles (A) containing a component are impregnated with at least a part of the radiation curable binder to form an impregnated layer having a thickness of 0.01 to 1.0 μm. Fine particles (A) Advance, to prepare an antiglare film at a coating liquid using a cross-linking degree different organic fine particles, is characterized in that the one used by selecting the organic fine particles that matches the impregnation degree.

In the method for producing an antiglare film of the present invention, examples of the material constituting the coating liquid are the same as those described in the above-described antiglare film of the present invention.
Moreover, the process similar to the method demonstrated in the anti-glare film of this invention mentioned above as the process of forming the said diffused layer is mentioned.

Also provided is a polarizing plate comprising a polarizing element, comprising the antiglare film of the present invention by bonding a light-transmitting substrate to the surface of the polarizing element. It is one of the inventions.

The polarizing element is not particularly limited, and for example, a polyvinyl alcohol film, a polyvinyl formal film, a polyvinyl acetal film, an ethylene-vinyl acetate copolymer saponified film, etc. dyed and stretched with iodine or the like can be used. In the laminating process of the polarizing element and the antiglare film of the present invention, it is preferable to saponify the light-transmitting substrate. By the saponification treatment, the adhesiveness is improved and an antistatic effect can be obtained.

This invention is also an image display apparatus provided with the said anti-glare film or the said polarizing plate on the outermost surface. The image display device may be a non-self-luminous image display device such as an LCD, or a self-luminous image display device such as a PDP, FED, ELD (organic EL, inorganic EL), or CRT.

An LCD that is a typical example of the non-self-luminous type includes a transmissive display and a light source device that irradiates the transmissive display from the back. When the image display device of the present invention is an LCD, the antiglare film of the present invention or the polarizing plate of the present invention is formed on the surface of the transmissive display.

In the case where the present invention is a liquid crystal display device having the antiglare film, the light source of the light source device is irradiated from below the antiglare film. Note that in the STN liquid crystal display device, a retardation plate may be inserted between the liquid crystal display element and the polarizing plate. An adhesive layer may be provided between the layers of the liquid crystal display device as necessary.

The PDP, which is the self-luminous image display device, includes a front glass substrate and a rear glass substrate disposed so as to face the front glass substrate with a discharge gas sealed therebetween. When the image display device of the present invention is a PDP, the above-described antiglare film is also provided on the surface of the surface glass substrate or the front plate (glass substrate or film substrate).

The self-luminous image display device is an ELD device that emits light when a voltage is applied, such as zinc sulfide or a diamine substance: a phosphor is deposited on a glass substrate, and the voltage applied to the substrate is controlled. It may be an image display device such as a CRT that converts light into light and generates an image visible to the human eye. In this case, the antiglare film described above is provided on the outermost surface of each display device as described above or the surface of the front plate.

In any case, the antiglare film of the present invention can be used for display display of a television, a computer, a word processor or the like. In particular, it can be suitably used for the surface of high-definition image displays such as CRTs, liquid crystal panels, PDPs, and ELDs.

The antiglare film of the present invention has a high definition because the height of the convex portion at the position corresponding to the organic fine particles (A) in the diffusion layer on the surface of the diffusion layer can be made low and gentle. Even when it is applied to a display, all of the antiglare property, the anti-glare property and the anti-scintillation property can be made excellent.
The organic fine particles (A) in the diffusion layer are formed with the above-mentioned impregnation layer, and the impregnation layer is formed in a state in which a radiation curable binder is mixed. It is possible to suitably prevent the light transmitted through the diffusion layer from being scattered at the interface between the organic fine particles (A) (impregnated layer) therein and the cured product of the radiation curable binder.
Furthermore, since the adhesion between the organic fine particles (A) in the diffusion layer and the cured product of the radiation curable binder is extremely excellent, the antiglare film of the present invention is applied to a sheet-like liquid crystal display. Even if it exists, a crack does not generate | occur | produce in the interface of the said organic fine particle (A) and the hardened | cured material of a radiation-curable binder.

2 is a cross-sectional SEM photograph of a diffusion layer of an antiglare film according to Example 1. 4 is a cross-sectional SEM photograph of a diffusion layer of an antiglare film according to Example 2.

The contents of the present invention will be described with reference to the following examples, but the contents of the present invention should not be construed as being limited to these examples.

Example 1
First, triacetyl cellulose (manufactured by Fuji Film Co., Ltd., thickness 80 μm) was prepared as a light transmissive substrate.
Next, a mixture (mass ratio; PETA / DPHA / PMMA) of pentaerythritol triacrylate (PETA), dipentaerythritol hexaacrylate (DPHA), and polymethyl methacrylate (PMMA) as a radiation curable binder (86/5/9). ) (Refractive index 1.51), and organic particles (A) were treated with acrylic particles (refractive index 1.49, average particle size 5.0 μm) with respect to 100 parts by mass of the radiation curable binder. 0.0 parts by mass, and a mixture of toluene and isopropyl alcohol (mass ratio 7: 3) as a solvent (mass ratio 7: 3) was mixed with 190 parts by mass with respect to 100 parts by mass of the radiation curable binder to prepare a coating solution.
The obtained coating liquid was allowed to stand for 24 hours, and then applied to a light-transmitting substrate using a Mayer bar, and dried at 70 ° C. at a flow rate of 1.2 m / s for 1 minute. .
Thereafter, the coating film was irradiated with ultraviolet rays (200 mJ / cm ² under a nitrogen atmosphere) to cure the radiation curable binder to form a diffusion layer, thereby producing an antiglare film. The thickness of the diffusion layer was 6.0 μm.

(Examples 2 to 8)
An antiglare film was produced in the same manner as in Example 1 except that the components to be added to the coating liquid and the standing conditions were as shown in Table 1.

(Comparative Example 1)
First, triacetyl cellulose (manufactured by Fuji Film Co., Ltd., thickness 80 μm) was prepared as a light transmissive substrate.
Next, a mixture of vinyl acetate resin (refractive index 1.46) and methyl methacrylate resin (refractive index 1.49) as a radiation curable binder (mass ratio; vinyl acetate resin / methyl methacrylate resin = 60/40) (Refractive index of 1.47), and acrylic particles (refractive index of 1.49, average particle size of 5.0 μm) as organic fine particles (A) are used in an amount of 9. A coating solution was prepared by blending 0 parts by mass with 190 parts by mass of a mixture of toluene and methyl ethyl ketone (mass ratio 7: 3) as a solvent with respect to 100 parts by mass of the radiation curable binder.
The obtained coating liquid was allowed to stand for 24 hours, and then applied to a light-transmitting substrate using a Mayer bar, and dried at 70 ° C. at a flow rate of 1.2 m / s for 1 minute. . The coating thickness was 6.0 μm.

(Comparative Examples 2 to 5)
An antiglare film was produced in the same manner as in Comparative Example 1 except that the components to be added to the coating liquid and the standing conditions were as shown in Table 1.

In Table 1, the details of symbols shown in the organic fine particles (A), fine particles (B), radiation curable binder and solvent are as follows. In Table 1, the contents of the organic fine particles (A), the fine particles (B) and the layered inorganic compound indicate the content (parts by mass) relative to 100 parts by mass of the radiation curable binder.

(Organic fine particles A)
A: Low cross-linked acrylic particles (refractive index 1.49, average particle size 5.0 μm, manufactured by Soken Chemical Co., Ltd.)
B: Highly crosslinked acrylic particles (refractive index 1.49, average particle size 5.0 μm, manufactured by Soken Chemical Co., Ltd.)
C: Low cross-linked acrylic particles (refractive index 1.49, average particle size 3.5 μm, manufactured by Soken Chemical Co., Ltd.)

(Fine particle B)
D: Highly cross-linked polystyrene particles (refractive index 1.59, average particle size 3.5 μm, manufactured by Soken Chemical Co., Ltd.)
E: Low cross-linked polystyrene particles (refractive index 1.59, average particle size 5.0 μm, manufactured by Soken Chemical Co., Ltd.)
F: Highly cross-linked acrylic-styrene particles (refractive index 1.52, average particle size 3.0 μm, manufactured by Soken Chemical Co., Ltd.)

(Layered inorganic compound)
M: Talc (refractive index 1.57, average particle size 0.8 μm, manufactured by Nippon Talc)

(Radiation curable binder)
P: Mixture of pentaerythritol triacrylate (PETA), dipentaerythritol hexaacrylate (DPHA) and polymethyl methacrylate (PMMA) (mass ratio: PETA / DPHA / PMMA = 86/5/9) (refractive index 1.51 )
Q: Pentaerythritol triacrylate (PETA) (refractive index 1.51)
R: a mixture of 60 parts by mass of vinyl acetate resin and 40 parts by mass of methyl methacrylate resin (refractive index 1.47)

(solvent)
X: Mixture of toluene and methyl ethyl ketone (mass ratio 7: 3)
Y: Mixture of toluene and methyl isobutyl ketone (mass ratio 8: 2)
Z: Mixture of toluene and isopropyl alcohol (mass ratio 7: 3)

The following evaluation was performed about the anti-glare film obtained by the Example and the comparative example. The results are shown in Table 2.

(Thickness of impregnated layer)
About the anti-glare film obtained in the examples and comparative examples, cut in the thickness direction of the diffusion layer, SEM observation at a magnification of 3000 to 50,000 times a cross section containing at least one organic fine particles (A), The portion where the organic fine particles (A) are impregnated with the radiation curable binder, the boundary between the organic fine particles (A) and the surrounding binder is relatively clear, and the radiation curable binder is contained in the organic fine particles (A). Was measured in the same manner for a total of five organic fine particles (A), and the average value of 10 measurement results was calculated. A cross-sectional SEM photograph of the diffusion layer of the antiglare film according to Example 1 is shown in FIG. 1, and a cross-sectional SEM photograph of the diffusion layer of the antiglare film according to Example 2 is shown in FIG.
In addition to the organic fine particles (A), when the fine particles (B) are further contained, the thickness of the impregnated layer on the fine particles can be measured in the same manner as described above.

(Haze)
The haze value of the antiglare films obtained in Examples and Comparative Examples was measured using a haze meter HR100 (manufactured by Murakami Color Research Laboratory Co., Ltd.) in accordance with haze (cloudiness) defined in JIS-K7136. .
Moreover, with respect to the anti-glare films obtained in Examples and Comparative Examples, a 60 ° C. × 90% RH × 1000 hour moist heat resistance test was performed to determine a change in haze value before and after the test.

(Mandrel test)
In accordance with JIS K5600, mandrel tests of the antiglare films obtained in Examples and Comparative Examples were performed with φ6 mm, φ8 mm, and φ10 mm of mandrels, and evaluated according to the following criteria.
◎: No crack at φ6 mm ○: No crack at φ8 mm Δ: No crack at φ10 mm ×: Crack at φ10 mm

(contrast)
The antiglare films obtained in Examples and Comparative Examples were bonded to a black acrylic plate using a transparent adhesive film for an optical film, and the surface condition of 15 antiglare films was measured by 1000 subjects. Visual sensory evaluation was performed from various directions under bright room conditions. It was determined whether or not glossy black color could be reproduced, and evaluated according to the following criteria.
◎: 10 or more people who answered good ○: 9-8 people who answered good Δ: 7-5 people who answered good ×: 4 or less people who answered good

(Glitter)
The polarizing plate on the outermost surface of the liquid crystal television “KDL-40X2500” manufactured by Sony Corporation was peeled off, and a polarizing plate without surface coating was attached.
Subsequently, the anti-glare films obtained in Examples and Comparative Examples are further coated on the transparent adhesive film for optical films (total light transmittance of 91% or more, haze of 0.3% so that the diffusion layer side is the outermost surface. Hereinafter, it was pasted by a product having a film thickness of 20 to 50 μm, for example, MHM series: manufactured by Niei Engineering Co., Ltd.
The subject was installed in a room under an environment with an illuminance of about 1,000 Lx, displayed on a white screen, and viewed from various angles up and down and left and right from a location about 1.5 to 2.0 m away from the liquid crystal television. Fifteen people performed visual sensory evaluation. It was determined whether or not glare was observed on the white screen display, and evaluation was performed according to the following criteria.
◎: 10 or more people who answered good ○: 9-8 people who answered good Δ: 7-5 people who answered good ×: 4 or less people who answered good

(Hard coat property)
The surface of the anti-glare film according to Examples, Comparative Examples and Reference Examples was subjected to a pencil hardness test by drawing five lines with a load of 750 g and 3H according to JIS K5600-5-4 (1999).
◎: 0 scratches in 3H pencil hardness test ○: 1-2 scratches in 3H pencil hardness test Δ: 3-4 scratches in 3H pencil hardness test

As shown in Table 2, in the antiglare film according to the example, an impregnation layer having a radiation curable average thickness of 0.05 to 0.8 μm is formed on the organic fine particles (A) in the diffusion layer. It had been. It was confirmed that these impregnated layers were impregnated with a radiation curable binder. In addition, the antiglare film according to the example has a haze value change of 0.9% or less before and after the wet heat resistance test, the mandrel test and glare evaluation of Example 1, the contrast evaluation of Examples 5 and 7, Although the glare evaluation of Example 1 and 6-8 was (triangle | delta), the mandrel test, contrast evaluation, and the glare evaluation result were favorable on the whole.
In the antiglare films according to Comparative Examples 1 to 4, the organic fine particles (A) in the diffusion layer are not formed with an impregnated layer, and the haze value change before and after the wet heat resistance test, mandrel test, contrast evaluation, and glare As a result of the evaluation, none were good. The antiglare film according to Comparative Example 5 had an impregnation layer having a thickness of 1.3 μm formed on the organic fine particles (A) in the diffusion layer, but was inferior in the evaluation of glare.

The antiglare film of the present invention is suitably used for displays such as cathode ray tube display devices (CRT), liquid crystal displays (LCD), plasma displays (PDP), electroluminescence displays (ELD), particularly high definition displays. Can do.

Claims (14)

An anti-glare film having a light-transmitting substrate and a diffusion layer formed on at least one surface of the light-transmitting substrate and having an uneven shape on the surface,
The diffusion layer is formed by applying a coating liquid containing an organic fine particle (A) and a radiation curable binder containing a (meth) acrylate monomer as an essential component onto at least one surface of the light-transmitting substrate. A film is formed by drying, and the film is cured.
The organic fine particles (A) in the diffusion layer have an impregnation layer impregnated with the radiation curable binder,
The impregnated layer has an average thickness of 0.01 to 1.0 μm,
The average particle diameter of the organic fine particles (A) before the impregnation layer is formed is 1.0 to 10.0 μm. 2. The antiglare film according to claim 1, wherein a change in haze value before and after the heat and humidity resistance test at 60 ° C. × 90% RH × 1000 hours is 1.5% or less. The anti-glare film according to claim 1 or 2, wherein the diffusion layer further contains fine particles (B) having an average particle size smaller than that of the organic fine particles (A). The antiglare film according to claim 1, 2 or 3, wherein the coating liquid contains at least a solvent which swells the organic fine particles (A). When the difference between the refractive index of the radiation curable binder and the refractive index of the organic fine particles (A) and fine particles (B) is Δ _A and Δ _B , Δ _A and Δ _B are expressed by the following formula (1). The antiglare film according to claim 3 or 4, wherein:
| Δ _A | <| Δ _B | (1) When the average particle diameter of the organic fine particles (A) is D _A 1 and the average particle diameter of the organic fine particles (A) in the diffusion layer is D _A 2, the D _A 1 and D _A 2 are expressed by the following formula (2 The antiglare film according to claim 3, 4, or 5.
0.01 μm <D _A 2−D _A 1 <1.0 μm (2) The average particle diameters of the organic fine particles (A) and fine particles (B) are D _A 1 and D _B 1 respectively, and the average particle diameters of the organic fine particles (A) in the diffusion layer and the fine particles (B) in the diffusion layer are each when the _{D a} 2 and _{D B} 2, wherein _{D a 1, D B 1,} D a 2 and _{D B} 2 is claim 3, 4, 5 or and satisfies the following formula (3) 6. The antiglare film according to 6.
D _A 2−D _A 1> D _B 2−D _B 1 ≧ 0 (3) The antiglare film according to claim 3, 4, 5, 6, or 7, wherein the fine particles (B) are organic fine particles. The anti-glare film according to claim 1, 2, 3, 4, 5, 6, 7 or 8, wherein the diffusion layer further contains a layered inorganic compound. The antiglare film according to claim 9, wherein the layered inorganic compound is talc. The diffusion layer has a convex portion at a position corresponding to the organic fine particles (A) in the diffusion layer on the surface, and the height of the convex portion is the following requirements (1), (2) and (3 The height of the convex portion at a position corresponding to the organic fine particles (C) on the surface of the diffusion layer (C) containing the organic fine particles (C) satisfying all of The antiglare film according to 3, 4, 5, 6, 7, 8, 9 or 10.
Requirement (1): Requirement (2) for forming the diffusion layer (C) under the same conditions as the diffusion layer containing the organic fine particles (A) except that the organic fine particles (C) are used instead of the organic fine particles (A). The organic fine particles (C) in the diffusion layer (C) have the same average particle diameter as the organic fine particles (A) in the diffusion layer (3): The organic fine particles (C) are impregnated in the diffusion layer (C) Layer does not form A method for producing an antiglare film comprising a light transmissive substrate and a diffusion layer formed on at least one surface of the light transmissive substrate and having an uneven shape on the surface,
On at least one surface of the light-transmitting substrate, a coating solution containing an organic fine particle (A) and a radiation curable binder containing a (meth) acrylate monomer as an essential component and a solvent is applied and dried to form a coating film. Forming, curing the coating film, and forming the diffusion layer,
The radiation curable binder and / or solvent includes a component that swells the organic fine particles (A),
The organic fine particles (A) are impregnated with the radiation curable binder to form an impregnation layer having a thickness of 0.01 to 1.0 μm, and an average particle diameter before the impregnation layer is formed. Is 1.0-10.0 μm,
Furthermore, the organic fine particles (A) are prepared by preparing an antiglare film in advance using a coating liquid using organic fine particles having different crosslinking degrees, and selecting organic fine particles that match the degree of impregnation. The manufacturing method of the anti-glare film characterized by the above-mentioned. A polarizing plate comprising a polarizing element,
A polarizing plate comprising the antiglare film according to claim 1, 2, 3, 4, 5, 6, 8, 9, 10, or 11 on the surface of the polarizing element. An image comprising the antiglare film according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11 or the polarizing plate according to claim 13 on an outermost surface. Display device.

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