JP7323986B2 - antiglare film - Google Patents

Description

TECHNICAL FIELD The present invention relates to an anti-glare film, and more particularly to an anti-glare film in which glare and anti-glare properties are significantly improved by using two specific types of particles.

Conventionally, in display devices such as liquid crystal displays, CRT displays, EL displays, plasma displays, etc., an antiglare film having an uneven structure on the surface is provided on the surface of the display in order to prevent reflection of fluorescent lights, external light, etc. ing.
As such an antiglare film, various types are known in which fine particles are dispersed in a transparent base resin to form an uneven structure on the surface (for example, Patent Documents 1 to 3).
By using an ultraviolet curable resin or the like as the base resin, the antiglare film exhibits hard coat properties and can be used as a protective film for polarizing plates or the like.

In recent years, high-definition display devices with small pixel sizes have been developed in order to improve image quality. In the display of such a high-definition display device, the uneven structure on the surface of the anti-glare film becomes a bright spot, and the problem of "glare" (unevenness in brightness) on the screen tends to occur.

Patent Document 2 discloses an antiglare film in which the surface haze value (external haze value) and the internal haze value of the antiglare layer are within specific ranges. Poor antiglare properties) and a small internal haze value is likely to cause surface glare (glare). No guidance is provided.

Further, in Patent Document 3, by defining the total haze value of the antiglare hard coat film, the value obtained by dividing the internal haze value by the total haze value, the surface roughness of the antiglare hard coat layer surface, etc., contradictory It is said that it is possible to deal with all of the issues of high contrast, anti-glare, prevention of white blurring, and high definition. However, even in Patent Document 3, specific means for realizing a desired haze value and surface shape are not clarified.

A display device with excellent visibility is demanded in order to cope with high definition, and the development of a high-performance anti-glare film for realizing such a display device is earnestly desired.

JP-A-6-018706 JP-A-11-305010 JP 2013-178533 A

The present invention has been made in view of the background art described above, and an object thereof is to provide an antiglare film that is excellent in antiglare properties, is less likely to cause glare, and is compatible with high definition.

As a result of intensive studies to solve the above problems, the present inventors have found that particles A for internal diffusion having a specific refractive index difference from the base resin of the antiglare layer, and particles for external diffusion that are lighter than the base resin. The inventors have found that if an antiglare film is produced by using Particle B in combination, internal diffusion and external diffusion can be designed separately, and both antiglare properties and glare prevention can be improved, and the present invention was completed. came to.

That is, the present invention provides an antiglare film having an antiglare layer on at least one surface of a substrate film, wherein the antiglare layer has a refractive index difference of 0.02 or more between the base resin and the base resin. An antiglare film characterized by containing particles A having a density exceeding 0.90 times the density of the base resin and particles B having a density not greater than 0.90 times the density of the base resin. It provides.

ADVANTAGE OF THE INVENTION According to this invention, the anti-glare film which is excellent in anti-glare property, is hard to generate|occur|produce glare, and can respond to high-definition can be provided.
In particular, since the particles B contained in the antiglare layer of the present invention have a low density, they easily float on the surface of the antiglare layer without using an additive such as an anti-settling agent. The particles floating on the surface of the antiglare layer contribute to the formation of an uneven structure on the surface and improve the antiglare property.
In addition, unlike the particles B, the particles A contained in the antiglare layer of the present invention do not float on the surface, but are uniformly present in the base resin, presumably contributing to internal diffusion.
In the present invention, as described above, two types of particles with different roles are used in the antiglare layer, so internal diffusion and external diffusion can be designed separately, and both antiglare properties and glare suppression are achieved. It can be an antiglare film.
The anti-glare film of the present invention suppresses glare and has sufficient hardness, so it is suitable for use as a protective film for polarizing plates of liquid crystal displays and the like.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the structure of the cross section of the anti-glare film of this invention. 4 is a cross-sectional SEM photograph of the antiglare film produced in Experimental Example 1. FIG. 4 is a cross-sectional SEM photograph of the antiglare film produced in Experimental Example 2. FIG. 4 is a cross-sectional SEM photograph of the antiglare film produced in Experimental Example 3. FIG. 4 is a cross-sectional SEM photograph of the antiglare film produced in Experimental Example 5. FIG.

Although the present invention will be described below, the present invention is not limited to the following embodiments, and can be arbitrarily modified and implemented.

The antiglare film 1 of the present invention is an antiglare film having an antiglare layer 11 on at least one surface of a base film 10 (Fig. 1 shows an example having an antiglare layer 11 on only one surface. ).
In the antiglare layer 11, the difference in refractive index between the base resin 12 and the base resin 12 is 0.02 or more, and the density of the particles A and the density of the base resin 12 exceeds 0.90 times the density of the base resin 12. It contains particles B that are less than or equal to 0.90 times the density of
The surface 11a of the antiglare layer has an uneven structure, and antiglare properties are exhibited by surface diffusion (the uneven structure is exaggerated in FIG. 1).

The base film 10 is a base for supporting the antiglare layer 11 thereon, and a transparent plastic film, glass plate, or the like can be used as appropriate.
Specific materials for the base film 10 include polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyarylate, polyethylene, polypropylene, cyclopolyolefin, polystyrene, triacetylcellulose (TAC), diacetylcellulose, Examples include poly(meth)acrylate, polyvinyl chloride, polyimide, polyamide, norbornene compound, and glass.

The average thickness of the base film 10 is not particularly limited, but is preferably 25 μm to 500 μm, particularly preferably 50 μm to 300 μm, from the viewpoints of strength for use as an antiglare film, ease of handling, and cost.

As the base film 10, one that has been subjected to easy-adhesion treatment such as plasma treatment, corona discharge treatment, far-ultraviolet irradiation treatment, formation of an undercoat easy-adhesion layer, or the like can be used.

The antiglare layer 11 includes, as essential components, a base resin 12, particles A having a refractive index difference of 0.02 or more with respect to the base resin 12, and particles B having a density of 0.90 times or less the density of the base resin 12. contains.

The "base resin 12" in the present invention means, of the materials forming the coating film (antiglare layer), particles (particles A, particles B, and other particles) described later, and components (resins) in general other than additives. Say. As the base resin 12, one type of resin may be used alone, or two or more types of resin may be used in combination.
The antiglare layer 11 is formed by dispersing or dissolving particles (particles A, particles B, and other particles) and additives described later in the base resin 12, and drying and/or curing the base resin 12. be done.

From the viewpoint of imparting scratch resistance to the antiglare layer 11, the base resin 12 preferably contains an actinic ray curable resin. From the viewpoint of enhancing the dispersibility of the particles, the base resin 12 preferably contains a thermoplastic resin. Moreover, it is particularly preferable that the base resin 12 contains both an actinic ray curable resin and a thermoplastic resin.

The actinic ray-curable resin that can be contained in the base resin 12 of the antiglare layer 11 of the present invention is an actinic ray-curable resin raw material containing an uncured actinic ray-curable resin (prepolymer) or a photopolymerizable monomer. , ultraviolet rays (UV), and electron beams (EB).
Among these, UV-curable resins cured with UV rays are particularly preferable from the viewpoint of abrasion resistance, cost, and availability of uncured actinic radiation-curable resins (prepolymers) as raw materials.
The actinic ray-curable resins used as raw materials may be used singly or in combination of two or more.

Specific examples of actinic ray-curable resins include resins obtained by curing (meth)acrylic prepolymers (in the present specification, "(meth)acryl" means "acryl" or "methacryl" and "(meth)acrylate" means "acrylate" or "methacrylate").

A (meth)acrylic prepolymer is a photopolymerizable prepolymer that can be crosslinked and cured by irradiation with actinic rays, and has two or more acryloyl groups in one molecule. structure.

There is no particular limitation on the type of (meth)acrylic prepolymer, and urethane (meth)acrylate, polyester (meth)acrylate, epoxy (meth)acrylate, melamine (meth)acrylate, polyfluoroalkyl (meth)acrylate, silicone (meth)acrylate, ) acrylates and the like can be used.
These may be used individually by 1 type, and may use 2 or more types together.

When the main component of the actinic radiation-curable resin raw material is the above (meth)acrylic prepolymer, a photopolymerizable monomer may be added to the actinic radiation-curable resin raw material.
Addition of a photopolymerizable monomer is preferable because the crosslinking curability is improved and the hardness of the antiglare layer is further improved.

Examples of photopolymerizable monomers include monofunctional (meth)acrylic monomers such as 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate and butoxyethyl (meth)acrylate. ; 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalate ester neopentylglycol di(meth)acrylate, etc. Bifunctional acrylic monomers; pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate and other polyfunctional (meth) acrylic monomers mentioned.
These may be used individually by 1 type, and may use 2 or more types together.

The actinic radiation curable resin raw material preferably contains a photopolymerization initiator and a photopolymerization accelerator in order to advance the curing reaction.

Specific examples of photopolymerization initiators include acetophenone, benzophenone, Michler's ketone, benzoin, benzyl methyl ketal, benzoyl benzoate, α-acyloxime ester, thioxanthone and the like.

In addition, the photopolymerization accelerator can reduce the polymerization hindrance due to oxygen during curing and increase the curing speed. mentioned.

Moreover, it is preferable to use an organic-inorganic hybrid resin among the actinic radiation-curable resins.
An “organic-inorganic hybrid resin” is a resin in which an organic component and an inorganic component are combined at the nano level. Organic-inorganic hybrid resins are different from conventional composites represented by glass fiber reinforced plastics (FRP). , the properties and functions of the organic and inorganic components can be synergistically enhanced.

The organic-inorganic hybrid resin may be one in which the organic component and the inorganic component have already reacted before being cured, and may be one in which the inorganic component reacts with the organic component by actinic ray irradiation. .

The size of the inorganic component in the organic-inorganic hybrid resin is set to 800 nm or less at which no geometric scattering of light occurs, and when particles are used, particles having an average particle size of 800 nm or less are used.
Examples of the inorganic component include metal oxides such as silica and titania, with silica being preferred. As silica, reactive silica having a photosensitive group having photopolymerization reactivity introduced on the surface thereof is more preferable.
In this specification, the "average particle size" of particles refers to the value of the volume average particle size (D50) that can be measured by a laser diffraction/scattering method. The average particle size when the shape of the particles is not spherical is calculated as the diameter equivalent to a sphere.

The content of the inorganic component in the organic-inorganic hybrid resin is preferably 10% by mass or more, more preferably 20% by mass or more. Also, it is preferably 65% by mass or less, more preferably 40% by mass or less.

As the organic component in the organic-inorganic hybrid resin, a compound having a polymerizable unsaturated group polymerizable with the inorganic component (preferably reactive silica) (for example, a compound having two or more polymerizable unsaturated groups in the molecule polyunsaturated organic compounds, monounsaturated organic compounds having one polymerizable unsaturated group in the molecule, etc.).

When the base resin 12 of the antiglare layer 11 contains an organic-inorganic hybrid resin, the particles B described later, which are considered to float on the surface of the antiglare layer 11 and contribute to external diffusion, are more likely to float. Makes it especially easy to play the effect.

The base resin 12 of the antiglare layer 11 of the present invention may contain a thermoplastic resin. By containing the thermoplastic resin, the dispersibility of the particles (especially the particles A) in the base resin 12 is likely to be improved. In addition, the surface of the particles becomes a shape as if it were covered with the resin component, which makes it easier to form irregularities on the surface of the coating film.

Specific examples of thermoplastic resins include polyvinyl acetal resins such as polyvinyl butyral and polyvinyl formal; polyester resins; (meth)acrylic resins; polyolefin resins such as polyethylene and polypropylene;
The thermoplastic resin may be used singly or in combination of two or more.

When the base resin 12 contains both the actinic ray curable resin and the thermoplastic resin, the content ratio is preferably 1 part by mass or more of the thermoplastic resin with respect to 100 parts by mass of the actinic ray curable resin, and 2 parts by mass. It is more preferably 3 parts by mass or more, and particularly preferably 3 parts by mass or more. Further, the thermoplastic resin is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and particularly preferably 10 parts by mass or less with respect to 100 parts by mass of the actinic radiation curable resin.
When it is at least the above lower limit, the particle surface is covered with the resin component, and the antiglare property and antiglare effect are likely to be improved. When it is equal to or less than the above upper limit, the base resin 12 is sufficiently cured, and the antiglare layer 11 having sufficient hardness can be easily obtained.

The refractive index of the base resin 12 is preferably 1.40 or higher, more preferably 1.45 or higher, and particularly preferably 1.50 or higher. Also, it is preferably 1.8 or less, more preferably 1.75 or less, and particularly preferably 1.7 or less.
The "refractive index of the base resin 12" means the refractive index of only the base resin 12 where no particles are present in the antiglare layer after forming the coating film (antiglare layer). However, when an organic-inorganic hybrid resin is used as the "base resin 12", the inorganic component of the organic-inorganic hybrid resin is included in the "refractive index and density of the base resin 12".

The density of the base resin 12 is preferably 1.1 g/cm ³ or higher, more preferably 1.15 g/cm ³ or higher, and particularly preferably 1.2 g/cm ³ or higher. Also, it is preferably 1.7 g/cm ³ or less, more preferably 1.65 g/cm ³ or less, and particularly preferably 1.6 g/cm ³ or less.
The "density of the base resin 12" means the density of only the base resin 12 in the antiglare layer-forming material where no particles, solvents, etc. are present, before the coating film (antiglare layer) is formed. Furthermore, when using a resin that reacts and hardens with heat, actinic rays, etc. as the "base resin 12", the density before hardening is defined as "the density of the base resin 12". However, when an organic-inorganic hybrid resin is used as the "base resin 12", the inorganic component of the organic-inorganic hybrid resin is included in the "density of the base resin 12".

The antiglare layer 11 of the present invention includes particles A having a refractive index difference of 0.02 or more with respect to the base resin 12 and having a density exceeding 0.90 times the density of the base resin 12 (that is, Among particles having a refractive index difference of 0.02 or more, particles excluding particles B described later) are contained. Since the particles A have a specific refractive index difference with the base resin 12, they contribute to internal diffusion and affect the internal haze value.

The difference in refractive index between the particles A and the base resin 12 is 0.02 or more, preferably 0.03 or more, more preferably 0.05 or more, and preferably 0.1 or more. More preferably, it is particularly preferably 0.15 or more, and most preferably 0.2 or more. Further, it is preferably 0.5 or less, more preferably 0.48 or less, still more preferably 0.46 or less, particularly preferably 0.43 or less, and 0.4 or less. Most preferably there is.
Within the above range, the internal haze value is likely to be within the appropriate range, and the antiglare property of the antiglare layer 11 is likely to be improved.

Either of the particles A and the base resin 12 may have a higher refractive index.

The density of the particles A is preferably 0.95 times or more, more preferably 1.0 times or more, that of the base resin 12 .
Within the above range, it becomes easier to uniformly disperse the particles A in the coating film, and an internal haze can be efficiently obtained.

The ^type of the particles A (substance used as the material for the particles A) is not particularly limited. 66, density: 1.40 g/cm ³ ), amino resin particles such as urea resin; silica particles (refractive index: 1.46, density: 2.20 g/cm ³ ); silicone particles (refractive index: 1.42 , density: 1.32 g/cm ³ ); talc (refractive index: 1.56, density: 2.70 g/cm ³ ); acrylic-styrene particles (refractive index: 1.56, density: 1.20 g/cm ³ ) and the like.

When the actinic ray-curable resin and the thermoplastic resin are used in combination within the above preferred ratio range, the refractive index of the base resin 12 tends to be a value of about 1.4 to 1.6.

The particles A may be organic particles or inorganic particles, but the organic particles have a higher affinity with the base resin than the inorganic particles, making it easier to uniformly disperse the particles in the coating film. It is preferred to use organic particles.
Further, when amino resin particles having a high refractive index as organic particles are used as the particles A, the difference in refractive index between the particles A and the base resin 12 is easily set within the above range, and the above effects are easily obtained. Become.

As the particles A, one type of particles may be used alone, or two or more types may be used in combination.

The distribution of the particles A in the antiglare layer 11 is not particularly limited, but since the particles A are particles that contribute to internal diffusion, it is desirable that they are uniformly dispersed in the antiglare layer 11 ( As will be described later, the particles B are desirably unevenly distributed near the surface of the antiglare layer 11).

The average particle size of the particles A is not particularly limited, but is preferably 0.8 μm or more, more preferably 1.0 μm or more, and particularly preferably 1.2 μm or more. Also, it is preferably 3 μm or less, more preferably 2.5 μm or less, and particularly preferably 2 μm or less.
When the average particle diameter is within the above range, the particles A are likely to be uniformly dispersed in the antiglare layer 11, the internal haze value is likely to be in an appropriate range, and the antiglare property is likely to be improved.

The shape of the particles A is not particularly limited. When the shape of the particles A is not spherical, the above average particle size is equivalent to a sphere.

The antiglare layer 11 of the present invention contains particles B having a density of 0.90 times or less the density of the base resin 12 . The particles B have a lower density (because they are lighter) than the base resin 12 , and thus easily float near the surface of the antiglare layer 11 . It is presumed that the particles B affect the shape of the uneven structure on the surface 11a of the antiglare layer and contribute to external diffusion.

Since the particles B are lighter than the base resin 12 and tend to float, they are usually presumed to be unevenly distributed near the surface 11a of the antiglare layer as shown in FIG.

The density of the particles B is 0.90 times or less the density of the base resin 12, preferably 0.85 times or less, more preferably 0.8 times or less, and particularly preferably 0.7 times or less.
Within the above range, the particles B are likely to float, and the anti-glare property is likely to be improved due to the formation of the uneven structure on the surface.

^The type of particles B (substance used as the material for particles B) is ^not particularly limited. Polyolefin particles such as polymers and propylene-butene copolymers; polystyrene (density: 1.05 g/cm ³ ) particles;
Polyolefin particles are particularly preferred as the particles B for the following reasons: they have a low density and tend to float; they tend to improve the scratch resistance of the antiglare layer;

The density of the particles B is preferably 0.6 g/cm ³ or more, particularly preferably 0.7 g/cm ³ or more. Also, it is preferably 1.2 g/cm ³ or less, particularly preferably 1.0 g/cm ³ or less.

As the particles B, one type of particles may be used alone, or two or more types may be used in combination.

The average particle size of the particles B is not particularly limited, but is preferably 1 μm or more, more preferably 1.5 μm or more, and particularly preferably 2 μm or more. Moreover, it is preferably 7 μm or less, more preferably 5 μm or less, and particularly preferably 4 μm or less.
The average particle size of the particles B is preferably 0.1 times or more, more preferably 0.3 times or more, and 0.5 times or more the average layer thickness of the antiglare layer 11. is particularly preferred. Also, it is preferably 1-fold or less, more preferably 0.95-fold or less, and particularly preferably 0.9-fold or less.
When the average particle diameter is within the above range, the particles B are likely to float in the antiglare layer 11, making it easier to control external diffusion.

The shape of the particles B is not particularly limited. If the shape of the particles B is not spherical (which is preferred), the above average particle size is equivalent to a sphere.
From the viewpoint of antiglare properties, the particles B are desirably amorphous particles.

The content ratio of the particles A and the particles B is preferably 0.2 parts by mass or more, more preferably 0.3 parts by mass or more, and 0.2 parts by mass or more of the particles A per 1 part by mass of the particles B. 4 parts by mass or more is particularly preferred. Further, the amount of particles A is preferably 2 parts by mass or less, more preferably 1.5 parts by mass or less, and particularly preferably 1 part by mass or less per 1 part by mass of particles B.
Within the above range, the particles B tend to float to the surface.

Further, the total ratio of the particles A and the particles B contained in the antiglare layer 11 is preferably 1% by mass or more, more preferably 3% by mass or more, with respect to the entire antiglare layer 11 (solid content). Especially preferred. Moreover, it is preferably 15% by mass or less, and particularly preferably 10% by mass or less.

The antiglare layer 11 may contain other particles that correspond to neither the particles A nor the particles B as long as the effects and performance exhibited by the present invention are not impaired. The total ratio of particles A and B to all particles is preferably 70% by mass or more, more preferably 90% by mass or more, and is 100% by mass or more (that is, particles A also It is particularly preferred that it does not contain other particles that are not also applicable to particles B).
However, the inorganic component contained in the organic-inorganic hybrid resin is not included in the "whole particles".

In the conventional technology, when a coating film (anti-glare layer) is formed by drying and curing a base resin in which fine particles are dispersed, the fine particles precipitate in the anti-glare layer, causing damage to the surface of the anti-glare layer. In some cases, the uneven structure cannot be sufficiently formed, and in order to prevent this, it was necessary to add a suspending agent. In the present invention, by using particles B having a low density, it is possible to form an uneven structure that can sufficiently contribute to external diffusion on the surface of the antiglare layer without adding an anti-settling agent.

The antiglare layer 11 of the present invention may optionally contain other particles (particles that are neither particles A nor particles B); lubricants, fluorescent brighteners, pigments, dyes, antistatic agents, flame retardants, antimicrobial agents Additives such as antifungal agents, antioxidants, plasticizers, leveling agents, flow control agents, antifoaming agents, dispersants, cross-linking agents, light stabilizers, etc. may be included.

When producing the antiglare film 1 of the present invention, an antiglare layer forming liquid containing a base resin, particles A, particles B, and, if necessary, the above other components, a solvent, etc., is poured onto the base film 10. Then, the antiglare layer 11 is formed by drying and curing.
The antiglare layer forming liquid is a liquid in which components such as particles (particles A and particles B) are dispersed and dissolved.

Although the actinic radiation-curable resin is usually liquid, the antiglare layer forming liquid may contain a solvent (such as an organic solvent). When containing a thermoplastic resin, it is preferable to contain a solvent.
Examples of such solvents include toluene, xylene, methyl ethyl ketone, ethyl acetate, butyl acetate, ethyl alcohol, isopropyl alcohol, butyl alcohol, and the like.
A solvent may be used individually by 1 type, and may use 2 or more types together.

The antiglare layer-forming liquid may be prepared by directly mixing each component contained in the antiglare layer 11, or by preparing a dispersion/solution in which each component is dispersed/dissolved in advance, and The antiglare layer-forming liquid may be prepared by mixing the dispersion liquid and the solution.

As a method for applying the antiglare layer forming liquid onto the base film 10, a conventionally known method can be used. For example, it can be applied using a bar coater, die coater, blade coater, spin coater, roll coater, gravure coater, flow coater (curtain coater), spray coater, screen printing or the like.

When the antiglare layer-forming liquid contains an actinic ray-curable resin, the antiglare layer 11 can be obtained by curing it by irradiation with actinic rays after drying as necessary.
As a method of irradiating active radiation, a method of irradiating ultraviolet rays in a wavelength range of 100 nm to 400 nm, preferably 200 nm to 400 nm emitted from an ultrahigh pressure mercury lamp, high pressure mercury lamp, low pressure mercury lamp, carbon arc, metal halide lamp, etc., scanning type and a method of irradiating an electron beam in a wavelength range of 100 nm or less emitted from a curtain-type electron beam accelerator.

The thickness of the antiglare layer 11 (average layer thickness; H in FIG. 1) is not particularly limited, but is preferably 2 μm or more, particularly preferably 3 μm or more. Moreover, 10 micrometers or less are preferable and 7 micrometers or less are especially preferable.
If it is at least the above lower limit, sufficient hardness can be exhibited. Moreover, when it is equal to or less than the above upper limit, curling is less likely to occur.

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples as long as it does not exceed the scope of the invention.

[Experimental example 1]
A transparent TAC (triacetyl cellulose) film having a thickness of 80 μm was used as a substrate film, and on one surface thereof, an antiglare layer forming liquid 1 having the following formulation was applied, dried, and irradiated with ultraviolet rays to obtain an average thickness of 4.0 μm. An antiglare film was produced by forming an antiglare layer of 5 μm.
The density and refractive index of the material of the liquid composition are the density and refractive index of only the solid content after removing the solvent.

<Composition of antiglare layer forming liquid 1>
・UV curable acrylic resin 12.5g
(Solid content 80%, density 1.20 g/cm ³ , refractive index 1.52)
・ Thermoplastic butyral resin 0.3g
(Solid content 100%, density 1.20 g/cm ³ , refractive index 1.48)
・Melamine resin particles 0.6 g
(Solid content 100%, average particle size 1.2 μm, density 1.50 g/cm ³ , refractive index 1.66)
・ 1 g of polypropylene particles
(Solid content 100%, average particle size 2.5 μm, density 0.91 g/cm ³ , refractive index 1.48)
・Fluorine leveling agent 0.05g
(40% solids, 60% solvent)
・ Photoinitiator 0.4 g
(100% solid content)
・ Solvent 30.7g

<Measurement of haze>
First, according to JIS K 7136, the haze value of the produced antiglare film and the haze value of the base film (transparent TAC film) having no antiglare layer formed thereon were measured.
A total haze value was obtained by subtracting the haze value of the base film (transparent TAC film) from the haze value of the produced antiglare film.

Next, a transparent adhesive sheet having a thickness of 20 μm was attached to the prepared antiglare layer side of the prepared antiglare film to obtain a sample for calculating an internal haze value. The haze value of the transparent adhesive sheet and the haze value of the internal haze value calculation sample were measured according to JIS K 7136.
The internal haze value was obtained by subtracting the haze value of the transparent adhesive sheet and the haze value of the base film (transparent TAC film) from the haze value of the sample for internal haze value calculation.

Finally, the external haze value was obtained by subtracting the internal haze value from the total haze value.

In addition, since the haze value of the transparent adhesive sheet is subtracted in the process of calculation as described above, it does not directly affect the internal haze value, the external haze value, and the total haze value. Therefore, a transparent adhesive sheet having a haze value of less than 5% was used.

<Observation of cross-sectional SEM photograph>
A cross section of the produced antiglare film was observed with a scanning electron microscope.

<Glare test>
The entire screen of a high-definition display tablet PC (number of pixels: 224 dpi) was displayed in green. A case where almost no glare was observed was evaluated as "○", and a case where glare was observed was evaluated as "X".

<Anti-glare test>
The surface opposite to the antiglare layer-coated surface of the produced antiglare film was attached to a 3 mm thick black acrylic plate via a transparent OCA having a thickness of about 25 μm. Next, the acrylic plate is placed with the antiglare layer side up, a fluorescent lamp attached directly above the acrylic plate (about 1 m20 cm) is turned on, light is applied to the antiglare layer, and fluorescent light is applied to the antiglare layer. It was determined by whether or not the light was visible. When it was blurred and could not be visually recognized, it was evaluated as "○", and when it was clearly visible, it was evaluated as "X".

[Experimental example 2]
An antiglare film was produced and evaluated in the same manner as in Experimental Example 1, except that the antiglare layer forming liquid 1 in Experimental Example 1 was changed to the antiglare layer forming liquid 2 having the following formulation.

<Composition of antiglare layer forming liquid 2>
・UV curable organic-inorganic hybrid acrylic resin 19.2g
(Solid content 50%, density 1.40 g/cm ³ , refractive index 1.49)
・ Thermoplastic butyral resin 0.3 g
(Solid content 100%, density 1.20 g/cm ³ , refractive index 1.48)
・ Melamine resin particles 0.45 g
(Solid content 100%, average particle size 1.2 μm, density 1.50 g/cm ³ , refractive index 1.66)
・ 1 g of polypropylene particles
(Solid content 100%, average particle size 2.5 μm, density 0.91 g/cm ³ , refractive index 1.48)
・Fluorine leveling agent 0.05g
(40% solids, 60% solvent)
・ Photoinitiator 0.4 g
(100% solid content)
・Solvent 22.1g

The UV-curable organic-inorganic hybrid acrylic resin used in the antiglare layer forming liquid 2 is a type of organic-inorganic hybrid resin that contains reactive nanosilica and forms an organic-inorganic composite by UV irradiation.

[Experimental example 3]
An antiglare film was produced and evaluated in the same manner as in Experimental Example 1, except that the antiglare layer forming liquid 1 in Experimental Example 1 was changed to the antiglare layer forming liquid 3 having the following formulation.

<Composition of antiglare layer forming liquid 3>
・UV curable acrylic resin 12.5g
(Solid content 80%, density 1.20 g/cm ³ , refractive index 1.52)
・ Thermoplastic butyral resin 0.3 g
(Solid content 100%, density 1.20 g/cm ³ , refractive index 1.48)
・Melamine resin particles 0.6g
(Solid content 100%, average particle size 1.2 μm, density 1.50 g/cm ³ , refractive index 1.66)
・Fluorine leveling agent 0.05g
(40% solids, 60% solvent)
・ Photoinitiator 0.4 g
(100% solid content)
・Solvent 28.0g

[Experimental example 4]
An antiglare film was produced and evaluated in the same manner as in Experimental Example 1, except that the antiglare layer forming liquid 1 in Experimental Example 1 was changed to the antiglare layer forming liquid 4 having the following formulation.

<Antiglare layer forming liquid 4 composition>
・UV curable acrylic resin 12.5g
(Solid content 80%, density 1.20 g/cm ³ , refractive index 1.52)
・ Thermoplastic butyral resin 0.3 g
(Solid content 100%, density 1.20 g/cm ³ , refractive index 1.48)
・ 1 g of polypropylene particles
(Solid content 100%, average particle size 2.5 μm, density 0.91 g/cm ³ , refractive index 1.48)
・Fluorine leveling agent 0.05g
(40% solids, 60% solvent)
・ Photoinitiator 0.4 g
(100% solid content)
・Solvent 29.0g

[Experimental example 5]
An antiglare film was produced and evaluated in the same manner as in Experimental Example 1, except that Antiglare Layer-Forming Liquid 1 in Experimental Example 1 was changed to Antiglare Layer-Forming Liquid 5 having the following formulation.

<Antiglare layer forming liquid 5 composition>
・UV curable acrylic resin 12.5g
(Solid content 80%, density 1.20 g/cm ³ , refractive index 1.52)
・ Thermoplastic butyral resin 0.3 g
(Solid content 100%, density 1.20 g/cm ³ , refractive index 1.48)
・Melamine resin particles 0.6g
(Solid content 100%, average particle size 1.2 μm, density 1.50 g/cm ³ , refractive index 1.66)
・ Polymethyl methacrylate particles 1 g
(Solid content 100%, average particle size 3.0 μm, density 1.20 g/cm ³ , refractive index 1.50)
・Fluorine leveling agent 0.05g
(40% solids, 60% solvent)
・ Photoinitiator 0.4 g
(100% solid content)
・ Solvent 30.7g

[Experimental example 6]
An antiglare film was produced and evaluated in the same manner as in Experimental Example 1, except that the average thickness of the antiglare layer was changed to 6.5 μm.

[Experimental example 7]
An antiglare film was produced and evaluated in the same manner as in Experimental Example 1, except that the average thickness of the antiglare layer was changed to 2.0 μm.

[result]
Table 1 shows the results of glare test, antiglare test, and haze measurement in Experimental Examples 1 to 7.
Cross-sectional SEM photographs of the antiglare films produced in Experimental Examples 1 to 3 and 5 are shown in FIGS.

The antiglare films of Experimental Examples 1 and 2, in which the antiglare layer contains two types of particles, the particles A and the particles B of the present invention, contain the particles B. Good results were obtained in terms of glare. Furthermore, the internal haze value was as designed, and the glare was also good.
On the other hand, the antiglare film of Experimental Example 3, which does not contain the particles B, is inferior in antiglare properties, and the antiglare film of Experimental Example 4, which does not contain the particles A, causes glare.
In addition, although two types of particles are used, instead of the particles B of the present invention, polymethyl methacrylate particles (particles B') with a large density are used to prepare the antiglare layer of Experimental Example 5. The glare film was inferior in antiglare properties.
The anti-glare film of Example 6, which had a thickness up to 2.4 times the average particle diameter of the particles B, gave good results.
The antiglare film of Experimental Example 7 gave good results, but the film thickness was thinner than the average particle diameter of the particles B, and the appearance was strongly grainy (there were many noticeable large irregularities). .

From the SEM photographs of the antiglare films, it can be seen that the particles B are floating near the surface of the antiglare layer 11 in the antiglare films of Experimental Examples 1 and 2 (FIGS. 2 and 3).
On the other hand, the antiglare film of Experimental Example 3 containing only particles A and not containing particles B (Fig. 4) and the antiglare film of Experimental Example 5 using particles B' having a large density instead of particles B ( In FIG. 5), no particles are present near the surface of the antiglare layer.
By using particles with a low density (particles B) in combination with particles A and causing the particles B to float near the surface of the antiglare layer 11, both antiglare properties and glare of the antiglare film are improved. guessed.

The anti-glare film of the present invention has excellent anti-glare properties, is less likely to glare, and is compatible with high definition. It is used.

1 antiglare film 10 base film 11 antiglare layer 11a antiglare layer surface 12 base resin A particle A
B particle B
B' Particles B' (polymethyl methacrylate particles)
H antiglare layer average layer thickness

Claims (8)

An antiglare film having an antiglare layer on at least one surface of a substrate film, wherein the antiglare layer is a base resin, and the refractive index difference from the base resin is 0.02 or more, and the density of the base resin Particles A having a density of more than 0.90 times the density of the base resin, and particles B having a density of 0.90 times or less than the density of the base resin, and the average particle size of the particles B is the antiglare layer It is 0.1 times or more and 0.95 times or less the average layer thickness, and the content ratio of the particles A and the particles B in the antiglare layer is 1 part by mass of the particles B to 1 part by mass of the particles A. An antiglare film characterized by containing 0.2 parts by mass or more and 0.6 parts by mass or less . The antiglare film according to claim 1, wherein the base resin contains an actinic ray-curable resin. 3. The antiglare film according to claim 2, wherein the actinic radiation curable resin is an organic-inorganic hybrid resin. 4. The antiglare film according to any one of claims 1 to 3, wherein the base resin contains a thermoplastic resin. 5. The antiglare film according to claim 1, wherein said particles B are polyolefin particles. 6. The antiglare film according to any one of claims 1 to 5, wherein the particles B are amorphous particles. 7. The antiglare film according to any one of claims 1 to 6 , wherein the particles A are amino resin particles. The antiglare film according to any one of claims 1 to 7 , wherein the particles B are unevenly distributed near the surface of the antiglare layer.

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