WO2020209288A1 - Anti-glare film, method for manufacturing anti-glare film, optical member, and image display device - Google Patents

Abstract

The present invention provides an anti-glare film in which reflection is suppressed.　Provided is an anti-glare film 10 in which an anti-glare layer (B) 12 is stacked on a light transmissive substrate (A) 11, the anti-glare film 10 being characterized in that recesses and projections are formed on the outermost surface on the anti-glare layer (B) 12 side of the anti-glare film 10, and the recesses and projections satisfy numerical expressions (1) and (2). (1): Ry ≥ 1.7 (2): θa ≥ 0.7 In numerical expression (1), Ry is the maximum height [µm] of the projections of the recesses and projections, and in numerical expression (2), θa is the average inclination angle [°] of the recesses and projections.

Description

Anti-glare film, manufacturing method of anti-glare film, optical member and image display device

The present invention relates to an antiglare film, a method for producing an antiglare film, an optical member, and an image display device.

Various image display devices such as a cathode tube display device (CRT), a liquid crystal display device (LCD), a plasma display panel (PDP), and an electroluminescence display (ELD) include fluorescent lamps and sunlight on the surface of the image display device. Anti-glare treatment is applied to prevent contrast deterioration due to reflection of external light and reflection of images, and in particular, as the screen size of image display devices increases, anti-glare films are used. The number of image display devices installed is increasing.

There are many documents describing antiglare films, for example, Patent Documents 1 and 2.

JP-A-2009-109683 Japanese Unexamined Patent Publication No. 2003-202416

From the viewpoint of visibility, the antiglare film needs to suppress reflection due to reflection of external light.

For example, in recent years, the demand for public information displays (PIDs) has been increasing. PID is often used outdoors. When a display (image display device) is used outdoors, reflection due to reflection of outside light is more likely to occur than when it is used indoors. If reflection occurs, it may be difficult to see the image.

Therefore, an object of the present invention is to provide an antiglare film in which glare is suppressed, a method for producing the antiglare film, an optical member, and an image display device.

In order to achieve the above object, the antiglare film of the present invention is used.
An antiglare film in which an antiglare layer (B) is laminated on a light transmissive base material (A).
Unevenness is formed on the outermost surface of the antiglare film on the antiglare layer (B) side.
The unevenness satisfies the following mathematical formulas (1) and (2).

Ry ≧ 1.7 (1)
θa ≧ 0.7 (2)

In the mathematical formula (1), Ry is the maximum height [μm] of the convex portion of the unevenness.
In the mathematical formula (2), θa is the average inclination angle [°] of the unevenness.

The method for producing an antiglare film of the present invention is
The antiglare layer (B) forming step of forming the antiglare layer (B) on the light transmissive base material (A) so as to satisfy the mathematical formulas (1) and (2) is included.
The antiglare layer (B) forming step includes a coating step of applying a coating liquid on the light transmissive base material (A) and drying the coated coating liquid to form a coating film. Including the coating film forming step
The method for producing an antiglare film of the present invention, wherein the coating liquid contains a resin and a solvent.

The optical member of the present invention is an optical member including the antiglare film of the present invention.

The image display device of the present invention is an image display device including the antiglare film of the present invention or the optical member of the present invention.

According to the present invention, it is possible to provide an antiglare film, an optical member, and an image display device in which glare is suppressed.

FIG. 1 is a cross-sectional view showing an example of the antiglare film of the present invention. FIG. 2 is a cross-sectional view showing another example of the antiglare film of the present invention. FIG. 3 is a cross-sectional view showing an example of an antiglare film.

Next, the present invention will be described in more detail with an example. However, the present invention is not limited by the following description.

In the antiglare film of the present invention, for example, the antiglare layer (B) may contain fine particles.

In the antiglare film of the present invention, for example, irregularities are formed on the surface of the antiglare layer (B) opposite to the light transmissive base material (A), and the weight average particle diameter of the fine particles is increased. It may be larger than the thickness obtained by subtracting the maximum height of the convex portion of the unevenness from the maximum thickness of the antiglare layer (B).

In the antiglare film of the present invention, for example, the weight average particle diameter of the fine particles may be in the range of 4 to 9 μm.

In the antiglare film of the present invention, for example, another layer may be further laminated on the surface of the antiglare layer (B) opposite to the light transmissive base material (A).

The antiglare film of the present invention is, for example, an antiglare film in which an antiglare layer (B) and another layer are laminated in the above order on a light transmissive base material (A), and the other layer. An antiglare film may be characterized in that irregularities are formed on the outermost surface of the film, and the irregularities satisfy the following mathematical formulas (1) and (2).

Ry ≧ 1.7 (1)
θa ≧ 0.7 (2)

In the mathematical formula (1), Ry is the maximum height [μm] of the convex portion of the unevenness.
In the mathematical formula (2), θa is the average inclination angle [°] of the unevenness.

The method for producing an antiglare film of the present invention may include, for example, a step of forming the antiglare layer (B) and a curing step of curing the coating film.

In the method for producing an antiglare film of the present invention, for example, the coating liquid may contain fine particles.

The optical member of the present invention may be, for example, a polarizing plate.

The image display device of the present invention may be, for example, a public information display.

[1. Anti-glare film]
As described above, the antiglare film of the present invention is an antiglare film in which an antiglare layer (B) is laminated on a light transmitting base material (A), and the antiglare film in the antiglare film. An uneven surface is formed on the outermost surface of the layer (B) side, and the unevenness satisfies the following mathematical formulas (1) and (2).

Ry ≧ 1.7 (1)
θa ≧ 0.7 (2)

In the mathematical formula (1), Ry is the maximum height [μm] of the convex portion of the unevenness.
In the mathematical formula (2), θa is the average inclination angle [°] of the unevenness.

The cross-sectional view of FIG. 1 shows an example of the configuration of the antiglare film of the present invention. As shown in the figure, in the antiglare film 10, the antiglare layer (B) 12 is laminated on one surface of the light transmissive base material (A) 11. The antiglare layer (B) 12 contains fine particles 12b and a thixotropy-imparting agent 12c in the resin layer 12a. Unevenness is formed on the outermost surface of the antiglare film 10 on the antiglare layer (B) 12 side (the surface of the antiglare layer (B) 12 on the side opposite to the light transmitting base material (A) 11). There is. The maximum height Ry of the convex portion of the unevenness is 1.7 μm or more. The average inclination angle θa (not shown) of the unevenness is 0.7 ° or more. Further, the particle diameter D of the fine particles 12b is larger than the film thickness t obtained by subtracting Ry from the maximum thickness d of the antiglare layer (B). However, FIG. 1 is an example, and the present invention is not limited thereto. For example, the antiglare film of the present invention may or may not contain fine particles and a thixotropy-imparting agent, respectively. Further, in FIG. 1, the particle diameter D of the fine particles 12b is larger than the film thickness t of the antiglare layer (B), but the present invention is not limited to this.

The cross-sectional view of FIG. 3 shows an example of the configuration of an antiglare film that is not the antiglare film of the present invention. This antiglare film is shown in FIG. 1 except that the maximum height Ry of the unevenness is less than 1.7 μm and the average projection angle θa (not shown) of the unevenness is less than 0.7 °. It is the same as the antiglare film.

Further, the cross-sectional view of FIG. 2 shows another example of the configuration of the antiglare film of the present invention. As shown in the figure, in the antiglare film 10, another layer 13 is further laminated on the surface of the antiglare layer (B) 12 opposite to the light transmissive base material (A) 11. The other layer 13 is not particularly limited, and may be, for example, a low refractive index layer, an antireflection layer, a high refractive index layer, a hard coat layer, an adhesive layer, or the like. Other than this, the configuration of the antiglare film 10 of FIG. 2 is the same as that of the antiglare film 10 of FIG. Further, in FIG. 2, the outermost surface of the antiglare film 10 on the antiglare layer (B) 12 side (the surface of the other layer 13 on the side opposite to the light transmissive base material (A) 11) has irregularities. It is formed. The maximum height Ry of the convex portion of the unevenness is 1.7 μm or more. The average inclination angle θa (not shown) of the unevenness is 0.7 ° or more. The maximum height of the portion of the antiglare film 10 other than the light transmissive base material (A) 11 (antiglare layer (B) 12 and other layers 13) is represented by d in the figure. Further, unevenness is formed on the surface of the antiglare layer (B) 12 on the side opposite to the light transmissive base material (A) 11 (the other layer 13 side). The film thickness obtained by subtracting the maximum height Ry'of the unevenness of the antiglare layer (B) 12 from the maximum thickness d'of the antiglare layer (B) 12 is represented by t in the figure. As shown, t is equal to d'-Ry'and equal to d-Ry. The particle diameter D of the fine particles 12b is larger than the film thickness t as in the case of FIG. 1, but as described above, the present invention is not limited to this. Further, as in the case of FIG. 1, the antiglare layer (B) 12 may or may not contain fine particles and a thixotropy-imparting agent, respectively. The other layer 13 is one layer in FIG. 2, but may be a plurality of layers. When the other layer 13 does not exist, Ry'is equal to Ry and d'is equal to d, as shown in FIG.

Hereinafter, each of the light transmissive base material (A), the antiglare layer (B), and the other layers will be described with further examples. In the following, the case where the antiglare layer (B) is an antiglare hard coat layer will be mainly described, but the present invention is not limited thereto.

The light transmissive base material (A) is not particularly limited, and examples thereof include a transparent plastic film base material. The transparent plastic film base material is not particularly limited, but is preferably one having excellent visible light transmittance (preferably 90% or more) and excellent transparency (preferably one having a haze value of 1% or less). For example, the transparent plastic film base material described in JP-A-2008-90263 can be mentioned. As the transparent plastic film base material, one having less birefringence optically is preferably used. The antiglare film of the present invention can also be used as a protective film for a polarizing plate, and in this case, the transparent plastic film base material includes triacetyl cellulose (TAC), polycarbonate, an acrylic polymer, and the like. A film formed of a polyolefin having a cyclic or norbornene structure is preferable. Further, in the present invention, as will be described later, the transparent plastic film base material may be the polarizer itself. With such a configuration, the protective layer made of TAC or the like is not required and the structure of the polarizing plate can be simplified, so that the number of manufacturing steps of the polarizing plate or the image display device can be reduced and the production efficiency can be improved. Further, with such a configuration, the polarizing plate can be further thinned. When the transparent plastic film base material is a polarizer, the antiglare layer (B) and the antireflection layer (C) serve as protective layers. Further, with such a configuration, the antiglare film also functions as a cover plate when mounted on the surface of a liquid crystal cell, for example.

In the present invention, the thickness of the light-transmitting base material (A) is not particularly limited, but in consideration of workability such as strength and handleability and thin layer property, for example, 10 to 500 μm and 20 to 300 μm. , Or in the range of 30-200 μm. The refractive index of the light transmissive substrate (A) is not particularly limited. The refractive index is, for example, in the range of 1.30 to 1.80 or 1.40 to 1.70.

In the antiglare film of the present invention, for example, the resin contained in the light transmissive base material (A) may contain an acrylic resin.

In the antiglare film of the present invention, for example, the light transmissive base material (A) may be an acrylic film.

Further, in the antiglare film of the present invention, as described above, irregularities are formed on the outermost surface on the antiglare layer (B) side, and the maximum height Ry of the irregularities is 1.7 μm or more. The maximum height Ry may be, for example, 2.0 μm or more or 2.3 μm or more, and may be, for example, 9 μm or less, 8 μm or less, 7 μm or less, or 6 μm or less. The maximum height Ry may be, for example, 1.7 to 9 μm, 1.7 to 8 μm, 2.0 to 7 μm, or 2.3 to 6 μm. Ry is preferably large from the viewpoint of suppressing glare, but is preferably not too large from the viewpoint of the haze value described later. In the present invention, the maximum height Ry is a numerical value based on JIS B 0601 (1994 version). The method for measuring Ry is not particularly limited, but for example, it can be measured by the measuring method described in Examples described later.

In the antiglare film of the present invention, the "outermost surface on the antiglare layer (B) side" is the outermost surface on the antiglare layer (B) side. Specifically, the "outermost surface on the antiglare layer (B) side" is the light transmissive base material (A) in the antiglare layer (B) when the other layer is not present (for example, FIG. 1). ) And the opposite side. Further, the "outermost surface on the antiglare layer (B) side" is the most on the side opposite to the light-transmitting base material (A) in the other layer when the other layer is present (for example, FIG. 2). The outer surface.

Further, as described above, the antiglare film of the present invention has an average inclination angle θa (°) of 0.7 or more in the uneven shape of the outermost surface on the antiglare layer (B) side. The average inclination angle θa may be, for example, 0.7 ° or more, 0.8 ° or more, 0.9 ° or more, or 1.0 ° or more, and is 8 ° or less, 7 ° or less, 6 ° or less. , Or 5 ° or less. The average inclination angle θa is, for example, 0.7 to 8 °, 0.7 to 7 °, 0.7 to 6 °, 0.7 to 5 °, 0.8 to 8 °, 0.8 to 7 °. , 0.8 to 6 °, 0.8 to 5 °, 0.9 to 8 °, 0.9 to 7 °, 0.9 to 6 °, 0.9 to 5 °, 1.0 to 8 °, It may be 1.0 to 7 °, 1.0 to 6 °, or 1.0 to 5 °. θa is preferably large from the viewpoint of suppressing glare, but is preferably not too large from the viewpoint of the haze value described later. Here, the average inclination angle θa is a value defined by the following mathematical formula (3). The average inclination angle θa can be measured, for example, by the method described in Examples described later.

Average inclination angle θa = tan ^-1 Δa (3)

In the above formula (3), Δa is the peak and valley of the adjacent peaks in the reference length L of the roughness curve defined in JIS B 0601 (1994 version) as shown in the following formula (4). It is a value obtained by dividing the total (h1 + h2 + h3 ... + Hn) of the difference (height h) from the lowest point by the reference length L. The roughness curve is a curve obtained by removing a surface waviness component longer than a predetermined wavelength from a cross-sectional curve with a phase difference compensation type high frequency filter. Further, the cross-sectional curve is a contour that appears at the cut end when the target surface is cut on a plane perpendicular to the target surface.

Δa = (h1 + h2 + h3 ... + hn) / L (4)

The antiglare film of the present invention may have, for example, a haze value of 4% or more, 6% or more, 10% or more, or 15% or more, for example, 50% or less, 40% or less, It may be 35% or less, or less than 30%. The haze value may be, for example, 4-50%, 6-40%, 10-40%, further 15-40%, or 15-35%. The haze value is the haze value (cloudiness) of the entire antiglare film according to JIS K 7136 (2000 version). Generally, in an antiglare film, when the haze value is large, it is easy to suppress reflection. However, if the haze value is too large, the display characteristics tend to be deteriorated, such as the image becoming unclear and the contrast in a dark place being lowered. However, according to the present invention, when Ry and θa satisfy the formulas (1) and (2), the haze value becomes, for example, 50% or less, 40% or less, 35% or less, or less than 30%. Even if it is small, the reflection can be suppressed. In order to reduce the haze value as much as possible, in addition to adjusting Ry and θa, the difference in refractive index between the resin and the fine particles, which will be described later, should be as small as possible (for example, in the range of 0.001 to 0.02). , The fine particles and the resin may be selected.

In the antiglare film of the present invention, for example, the antiglare layer (B) may contain a resin and a filler. The filler may contain at least one of the microparticles and the thixotropic agent.

In the antiglare film of the present invention, for example, the resin contained in the antiglare layer (B) may contain an acrylate resin (also referred to as an acrylic resin).

In the antiglare film of the present invention, for example, the resin contained in the antiglare layer (B) may contain a urethane acrylate resin.

In the antiglare film of the present invention, for example, the resin contained in the antiglare layer (B) may be a copolymer of a curable urethane acrylate resin and a polyfunctional acrylate.

In the antiglare film of the present invention, for example, the antiglare layer (B) is formed by using an antiglare layer forming material containing a resin and a filler, and the antiglare layer (B) is formed by the filler. It may have an agglomerated portion that forms a convex portion on the surface of the antiglare layer (B) by aggregating. Further, in the agglomerated portion forming the convex portion, a plurality of the fillers may be present in a state of being gathered in one direction in the surface direction of the antiglare layer (B). In the image display device of the present invention, for example, the antiglare film of the present invention may be arranged so that one direction in which a plurality of the fillers are gathered coincides with the long side direction of the black matrix pattern. ..

In the antiglare film of the present invention, the thixotropy-imparting agent may be at least one selected from the group consisting of, for example, organic clay, oxidized polyolefin and modified urea. Further, the thixotropy-imparting agent may be, for example, a thickener.

In the antiglare film of the present invention, for example, even if the thixotropy-imparting agent is contained in the range of 0.2 to 5 parts by weight with respect to 100 parts by weight (mass) of the resin of the antiglare layer (B). Good.

In the antiglare film of the present invention, the fine particles are contained in the range of, for example, 0.2 to 12 parts by weight or 0.5 to 12 parts by weight with respect to 100 parts by weight of the resin of the antiglare layer (B). It may be.

In the method for producing an antiglare film of the present invention, the surface shape of the antiglare film is further adjusted by adjusting the number of parts by weight of the fine particles with respect to 100 parts by weight of the resin in the antiglare layer forming material. You may.

The antiglare layer (B) is coated, for example, by applying a coating liquid containing the resin, the filler and a solvent to at least one surface of the light transmissive substrate (A), as will be described later. It is formed by forming a film and then removing the solvent from the coating. Examples of the resin include thermosetting resins and ionizing radiation curable resins that are cured by ultraviolet rays or light. As the resin, a commercially available thermosetting resin, an ultraviolet curable resin, or the like can also be used.

As the thermosetting resin or the ultraviolet curable resin, for example, a curable compound having at least one group of an acrylate group and a methacrylate group that is cured by heat, light (ultraviolet rays, etc.) or an electron beam can be used. Silicone resin, polyester resin, polyether resin, epoxy resin, urethane resin, alkyd resin, spiroacetal resin, polybutadiene resin, polythiol polyene resin, oligomers such as methacrylate and prepolymers of polyfunctional compounds such as polyhydric alcohol can give. One of these may be used alone, or two or more thereof may be used in combination.

For the resin, for example, a reactive diluent having at least one group of an acrylate group and a methacrylate group can be used. As the reactive diluent, for example, the reactive diluent described in JP-A-2008-88309 can be used, and includes, for example, monofunctional acrylate, monofunctional methacrylate, polyfunctional acrylate, polyfunctional methacrylate and the like. As the reactive diluent, trifunctional or higher functional acrylates and trifunctional or higher functional methacrylates are preferable. This is because the hardness of the antiglare layer (B) can be made excellent. Examples of the reactive diluent include butanediol glycerin ether diacrylate, isocyanuric acid acrylate, and isocyanuric acid methacrylate. One of these may be used alone, or two or more thereof may be used in combination.

The fine particles for forming the antiglare layer (B) impart antiglare property by forming the surface of the antiglare layer (B) to be formed into an uneven shape, and also set the haze value of the antiglare layer (B). Its main function is to control. The haze value of the antiglare layer (B) can be designed by controlling the difference in refractive index between the fine particles and the resin. Examples of the fine particles include inorganic fine particles and organic fine particles. The inorganic fine particles are not particularly limited, and for example, silicon oxide particles, titanium oxide particles, aluminum oxide particles, zinc oxide particles, tin oxide particles, calcium carbonate particles, barium sulfate particles, talc particles, kaolin particles, calcium sulfate particles and the like. Can be given. The organic fine particles are not particularly limited, and for example, polymethylmethacrylate resin powder (PMMA particles), silicone resin powder, polystyrene resin powder, polycarbonate resin powder, acrylic styrene resin powder, benzoguanamine resin powder, melamine resin powder, and polyolefin. Examples thereof include resin powder, polyester resin powder, polyamide resin powder, polyimide resin powder, and polyfluorinated ethylene resin powder. One type of these inorganic fine particles and organic fine particles may be used alone, or two or more types may be used in combination.

The particle size (D) (weight average particle size) of the fine particles is not particularly limited, but is, for example, in the range of 2 to 10 μm. By setting the weight average particle diameter of the fine particles within the above range, for example, an antiglare film having more excellent antiglare properties and suppressed glare can be obtained. From the viewpoint of suppressing reflection from an oblique direction, it is preferable that the weight average particle diameter of the fine particles is not too small. From the viewpoint of suppressing reflection from the front direction, it is preferable that the weight average particle diameter of the fine particles is not too large. The weight average particle diameter of the fine particles may be, for example, 4 μm or more, and may be, for example, 9 μm or less, or 8 μm or less. The weight average particle size of the fine particles may be, for example, 4 to 9 μm or 4 to 8 μm. The weight average particle size of the fine particles can be measured by, for example, the Coulter counting method. For example, using a particle size distribution measuring device (trade name: Coulter Multisizer, manufactured by Beckman Coulter) using the pore electrical resistance method, an electrolytic solution corresponding to the volume of the fine particles when the fine particles pass through the pores. By measuring the electric resistance, the number and volume of the fine particles are measured, and the weight average particle diameter is calculated.

The shape of the fine particles is not particularly limited, and may be, for example, a bead-shaped substantially spherical shape or an irregular shape such as powder, but a substantially spherical shape is preferable, and an aspect ratio is more preferable. It is a substantially spherical fine particle having a ratio of 1.5 or less, and most preferably a spherical fine particle.

The content of the fine particles in the antiglare layer (B) is not particularly limited, but can be appropriately set in consideration of, for example, the surface shape of the antiglare layer (B). The relationship between the content of the fine particles (the number of parts by weight with respect to the resin) and the weight average particle diameter and the surface shape of the antiglare layer (B) will be described later.

In the antiglare layer (B), the filler may be fine particles and a thixotropy-imparting agent. The thixotropy-imparting agent may be contained alone, or may further contain the thixotropy-imparting agent in addition to the fine particles. By including the thixotropy-imparting agent, it is possible to easily control the aggregated state of the fine particles. Examples of the thixotropy-imparting agent include organic clay, oxidized polyolefin, modified urea and the like.

The organic clay is preferably a layered clay that has been organically treated in order to improve the affinity with the resin. The organic clay may be prepared in-house or a commercially available product may be used. Examples of the commercially available products include Lucentite SAN, Lucentite STN, Lucentite SEN, Lucentite SPN, Somasif ME-100, Somasif MAE, Somasif MTE, Somasif MEE, and Somasif MPE (trade names, all of which are Corp Chemical Co., Ltd.). ); Esben, Esben C, Esben E, Esben W, Esben P, Esben WX, Esben N-400, Esben NX, Esben NX80, Esben NO12S, Esben NEZ, Esben NO12, Esben NE, Esben NZ, Esben NZ70, Olga Knight, Organite D, Organite T (trade name, all manufactured by Hojun Co., Ltd.); Kunipia F, Kunipia G, Kunipia G4 (trade name, all manufactured by Kunimine Industries, Ltd.); Chixogel VZ, Clayton HT, Clayton 40 (Product names, all manufactured by Rockwood Additives), etc.

The above-mentioned polyolefin oxide may be prepared in-house or a commercially available product may be used. Examples of the commercially available product include Disparon 4200-20 (trade name, manufactured by Kusumoto Kasei Co., Ltd.), Fronon SA300 (trade name, manufactured by Kyoeisha Chemical Co., Ltd.) and the like.

The modified urea is a reaction product of an isocyanate monomer or its adduct and an organic amine. The modified urea may be prepared in-house or a commercially available product may be used. Examples of the commercially available product include BYK410 (manufactured by Big Chemie).

The thixotropy-imparting agent may be used alone or in combination of two or more.

The ratio of the thixotropy-imparting agent in the antiglare layer (B) is preferably in the range of 0.2 to 5 parts by weight, more preferably in the range of 0.4 to 4 parts by weight, based on 100 parts by weight of the resin. is there.

The maximum thickness (d') of the antiglare layer (B) is not particularly limited, but is preferably in the range of 3 to 12 μm. By setting the maximum thickness (d') of the antiglare layer (B) to the above range, for example, it is possible to prevent the occurrence of curls in the antiglare film, and there is a problem of deterioration in productivity such as poor transportability. Can be avoided. When the thickness (d) is in the range, the weight average particle diameter (D) of the fine particles is preferably in the range of 4 to 9 μm as described above. By combining the maximum thickness (d') of the antiglare layer (B) and the weight average particle diameter (D) of the fine particles as described above, an antiglare film having excellent antiglare properties can be obtained. it can. The maximum thickness (d') of the antiglare layer (B) is more preferably in the range of 4 to 8 μm.

The ratio D / d'of the thickness (d') of the antiglare layer (B) to the weight average particle diameter (D) of the fine particles is, for example, 1 or less, less than 1, 0.98 or less, 0.96 or less. , 0.93 or less, or 0.90 or less, and may be 0.5 or more, 0.6 or more, 0.7 or more, or 0.8 or more. With such a relationship, it is possible to obtain an antiglare film having more excellent antiglare properties and suppressed glare. For example, when D / d'is large, Ry and θa tend to be large.

In the antiglare film of the present invention, for example, the antiglare layer (B) has an agglomerated portion that forms a convex portion on the surface of the antiglare layer (B) by aggregating the filler. In the agglomerated portion forming the convex portion, a plurality of the fillers may be present in a state of being gathered in one direction in the plane direction of the antiglare layer (B). Thereby, for example, it is possible to prevent the reflection of the fluorescent lamp and the like. However, the antiglare film of the present invention is not limited to this.

The surface shape of the antiglare layer (B) is, for example, a film thickness t obtained by subtracting the maximum height Ry'of the unevenness of the antiglare layer (B) from the maximum thickness d'of the antiglare layer (B). It can be designed by adjusting the weight average particle diameter D of the fine particles. Specifically, for example, when the weight average particle diameter D of the fine particles is relatively large with respect to the film thickness t of the antiglare layer (B), the Ry and θa tend to be large. The film thickness t can be adjusted, for example, by the coating thickness of the resin. The surface shape of the antiglare layer (B) can also be designed by adjusting the number of parts by weight of the fine particles with respect to 100 parts by weight of the resin in the antiglare layer forming material. For example, when the number of parts by weight of the fine particles is relatively large with respect to the resin, θa tends to be large.

Further, the antiglare film of the present invention is, for example, a resin derived from the light transmissive base material (A) and the resin between the light transmissive base material (A) and the antiglare layer (B). It may have an intermediate layer containing the resin derived from the antiglare layer (B). By controlling the thickness of the intermediate layer, the surface shape of the antiglare layer (B) can be controlled. For example, when the thickness of the intermediate layer is increased, the Ry and θa are likely to be increased, and when the thickness of the intermediate layer is decreased, the Ry and θa are likely to be decreased.

In the present invention, the mechanism by which the intermediate layer (also referred to as permeation layer or compatible layer) is formed is not particularly limited, but is formed, for example, in the drying step in the method for producing an antiglare film of the present inventor. .. Specifically, for example, in the drying step, the coating liquid for forming the antiglare layer (B) permeates the light-transmitting base material (A) and is derived from the light-transmitting base material (A). The intermediate layer containing the resin and the resin derived from the antiglare layer (B) is formed. The resin contained in the intermediate layer is not particularly limited, and for example, the resin contained in the light transmissive base material (A) and the resin contained in the antiglare layer (B) are simply mixed (compatible). It may be a plastic one. Further, as the resin contained in the intermediate layer, for example, at least one of the resin contained in the light transmissive base material (A) and the resin contained in the antiglare layer (B) is heated, irradiated with light, or the like. It may be chemically changed by.

The thickness ratio R of the intermediate layer defined by the following formula (5) is not particularly limited, but is, for example, 0.10 to 0.80, for example, 0.15 or more, 0.20 or more, 0.25. It may be 0.30 or more, 0.40 or more, or 0.45 or more, for example, 0.75 or less, 0.70 or less, 0.65 or less, 0.60 or less, 0.50 or less, It may be 0.40 or less, 0.45 or less, or 0.30 or less. The thickness ratio R of the intermediate layer is, for example, 0.15 to 0.75, 0.20 to 0.70, 0.25 to 0.65, 0.30 to 0.60, 0.40 to 0.50. , 0.45 to 0.50, 0.15 to 0.45, 0.15 to 0.40, 0.15 to 0.30, or 0.20 to 0.30. The intermediate layer can be confirmed, for example, by observing the cross section of the antiglare film with a transmission electron microscope (TEM), and the thickness can be measured.

_{R = [D C / (D} C + D B)] (5)

In Equation (5), _{D B} is the thickness [[mu] m] of the antiglare layer (B), _{D C} is the thickness of the intermediate layer [[mu] m].

The surface shape of the antiglare layer (B) can also be designed by controlling the aggregated state of the filler contained in the antiglare layer forming material. The agglomerated state of the filler can be controlled by, for example, the material of the filler (for example, the chemically modified state of the surface of the fine particles, the affinity for the solvent or the resin, etc.), the type of the resin (binder) or the solvent, the combination, and the like. In addition, the thixotropy-imparting agent can precisely control the aggregated state of the fine particles.

In the antiglare film of the present invention, the convex portion may have a gentle shape to prevent the generation of protrusions on the surface of the antiglare layer (B), which is an appearance defect. Not limited to this. Further, in the antiglare film of the present invention, for example, some of the fine particles may be present at positions where the antiglare layer (B) directly or indirectly overlaps in the thickness direction.

The other layer is not particularly limited, and may be, for example, a low refractive index layer, an antireflection layer, a high refractive index layer, a hard coat layer, an adhesive layer, or the like, as described above. Further, the other layer may be one layer or a plurality of layers, and in the case of a plurality of layers, one type or a plurality of types may be used. For example, the other layer may be an optical thin film whose thickness and refractive index are strictly controlled, or two or more layers of the optical thin film.

[2. Manufacturing method of antiglare film]
The method for producing the antiglare film of the present invention is not particularly limited and may be produced by any method, but it is preferably produced by the method for producing the antiglare film of the present invention.

The method for producing the antiglare film can be carried out as follows, for example.

First, the antiglare layer (B) is formed on the light transmissive base material (A) so as to satisfy the mathematical formulas (1) and (2) (antiglare layer (B) forming step). As a result, a laminate of the light-transmitting base material (A) and the antiglare layer (B) is produced. As described above, the antiglare layer (B) forming step includes a coating step of applying a coating liquid on the light transmissive substrate (A) and a drying coating of the coated coating liquid. It includes a coating film forming step of forming a film. Further, for example, as described above, the antiglare layer (B) forming step may further include a curing step of curing the coating film. The curing can be performed, for example, after the drying, but is not limited thereto. The curing can be performed by, for example, heating, light irradiation, or the like. The light is not particularly limited, but may be, for example, ultraviolet rays or the like. The light source for light irradiation is not particularly limited, but may be, for example, a high-pressure mercury lamp or the like.

As described above, the coating liquid contains a resin and a solvent. The coating liquid may be, for example, an antiglare layer forming material (coating liquid) containing the resin, the particles, the thixotropy-imparting agent, and the solvent.

The coating liquid preferably exhibits thixotropic properties, and the Ti value defined by the following formula is preferably in the range of 1.3 to 3.5, more preferably 1.4 to 3. It is in the range of 2, and more preferably in the range of 1.5 to 3.

Ti value = β1 / β2

In the above formula, β1 is a viscosity measured under the condition of a shear rate of 20 (1 / s) using a HAAKE Leostress RS6000, and β2 is a viscosity measured using a HAAKE Leostress RS6000 with a shear rate of 200 (1 / s). It is the viscosity measured under the conditions of.

If the Ti value is 1.3 or more, problems such as appearance defects and deterioration of antiglare and white blur characteristics are unlikely to occur. Further, when the Ti value is 3.5 or less, problems such as the particles not agglomerating and becoming dispersed are unlikely to occur.

Further, the coating liquid may or may not contain a thixotropy-imparting agent, but it is preferable to include the thixotropy-imparting agent because it tends to exhibit thixotropy. Further, as described above, when the coating liquid contains the thixotropy-imparting agent, an effect of preventing the sedimentation of the particles (thixotropy effect) can be obtained. Further, the surface shape of the antiglare film can be freely controlled in a wider range by the shear aggregation of the thixotropy-imparting agent itself.

The solvent is not particularly limited, and various solvents can be used, and one type may be used alone or two or more types may be used in combination. In order to obtain the antiglare film of the present invention, the optimum solvent type and solvent ratio may be appropriately selected according to the composition of the resin, the types and contents of the particles and the thixotropy-imparting agent. The solvent is not particularly limited, but for example, alcohols such as methanol, ethanol, isopropyl alcohol (IPA), butanol, t-butyl alcohol (TBA), 2-methoxyethanol; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopenta. Ketones such as non-ketones; esters such as methyl acetate, ethyl acetate, butyl acetate; ethers such as diisopropyl ether and propylene glycol monomethyl ether; glycols such as ethylene glycol and propylene glycol; cellosolves such as ethyl cellosolve and butyl cellosolve; Aliphatic hydrocarbons such as hexane, heptane and octane; aromatic hydrocarbons such as benzene, toluene and xylene can be mentioned. Further, for example, the solvent may contain a hydrocarbon solvent and a ketone solvent. The hydrocarbon solvent may be, for example, an aromatic hydrocarbon. The aromatic hydrocarbon may be at least one selected from the group consisting of, for example, toluene, o-xylene, m-xylene, p-xylene, ethylbenzene, and benzene. The ketone solvent may be, for example, at least one selected from the group consisting of cyclopentanone, acetone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, cyclohexanone, isophorone, and acetophenone. The solvent preferably contains, for example, the hydrocarbon solvent (eg toluene) in order to dissolve the thixotropy-imparting agent (eg, thickener). The solvent may be, for example, a solvent in which the hydrocarbon solvent and the ketone solvent are mixed at a mass ratio of 90:10 to 10:90. The mass ratio of the hydrocarbon solvent to the ketone solvent may be, for example, 80:20 to 20:80, 70:30 to 30:70, or 40:60 to 60:40. In this case, for example, the hydrocarbon solvent may be toluene and the ketone solvent may be methyl ethyl ketone. Further, the solvent may contain, for example, toluene and further contain at least one selected from the group consisting of ethyl acetate, butyl acetate, IPA, methyl isobutyl ketone, methyl ethyl ketone, methanol, ethanol, and TBA. Good.

When, for example, an acrylic film is used as the light-transmitting base material (A) to form an intermediate layer (permeation layer), a good solvent for the acrylic film (acrylic resin) can be preferably used. As the solvent, for example, as described above, a solvent containing a hydrocarbon solvent and a ketone solvent may be used. The hydrocarbon solvent may be, for example, an aromatic hydrocarbon. The aromatic hydrocarbon may be at least one selected from the group consisting of, for example, toluene, o-xylene, m-xylene, p-xylene, ethylbenzene, and benzene. The ketone solvent may be, for example, at least one selected from the group consisting of cyclopentanone, acetone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, cyclohexanone, isophorone, and acetophenone. The solvent may be, for example, a solvent in which the hydrocarbon solvent and the ketone solvent are mixed at a mass ratio of 90:10 to 10:90. The mass ratio of the hydrocarbon solvent to the ketone solvent may be, for example, 80:20 to 20:80, 70:30 to 30:70, or 40:60 to 60:40. In this case, for example, the hydrocarbon solvent may be toluene and the ketone solvent may be methyl ethyl ketone.

When, for example, triacetyl cellulose (TAC) is used as the light-transmitting base material (A) to form an intermediate layer (permeation layer), a good solvent for TAC can be preferably used. Examples of the solvent include ethyl acetate, methyl ethyl ketone, cyclopentanone and the like.

Further, by appropriately selecting the solvent, the thixotropy to the antiglare layer forming material (coating liquid) can be satisfactorily exhibited when the thixotropy-imparting agent is contained. For example, when organic clay is used, toluene and xylene can be preferably used alone or in combination. For example, when polyolefin oxide is used, methyl ethyl ketone, ethyl acetate, and propylene glycol monomethylmeter are preferably used alone. It can be used or used in combination. For example, when modified urea is used, butyl acetate and methyl isobutyl ketone can be preferably used alone or in combination.

Various leveling agents can be added to the antiglare layer forming material. As the leveling agent, for example, a fluorine-based or silicone-based leveling agent can be used for the purpose of preventing uneven coating (uniformizing the coated surface). In the present invention, when antifouling property is required on the surface of the antiglare layer (B), or as described later, an antireflection layer (low refractive index layer) or a layer containing an interlayer filler is placed on the antiglare layer (B). The leveling agent can be appropriately selected depending on the case where it is formed in. In the present invention, for example, by incorporating the thixotropy-imparting agent, thixotropy can be exhibited in the coating liquid, so that uneven coating is less likely to occur. In this case, for example, it has an advantage that the options of the leveling agent can be expanded.

The blending amount of the leveling agent is, for example, 5 parts by weight or less, preferably 0.01 to 5 parts by weight, based on 100 parts by weight of the resin.

Pigments, fillers, dispersants, plasticizers, ultraviolet absorbers, surfactants, antifouling agents, antioxidants and the like are added to the antiglare layer forming material as needed, as long as the performance is not impaired. May be done. One type of these additives may be used alone, or two or more types may be used in combination.

As the antiglare layer forming material, for example, a conventionally known photopolymerization initiator as described in JP-A-2008-88309 can be used.

Examples of the method of applying the coating liquid onto the light transmissive substrate (A) to form a coating film include a fanten coating method, a die coating method, a spin coating method, a spray coating method, and a gravure coating method. , Roll coating method, bar coating method and other coating methods can be used.

Next, as described above, the coating film is dried and cured to form an antiglare layer (B). The drying may be, for example, natural drying, air drying by blowing wind, heat drying, or a method in which these are combined.

The drying temperature of the coating liquid for forming the antiglare layer (B) may be, for example, in the range of 30 to 200 ° C. The drying temperature may be, for example, 40 ° C. or higher, 50 ° C. or higher, 60 ° C. or higher, 70 ° C. or higher, 80 ° C. or higher, 90 ° C. or higher, or 100 ° C. or higher, 190 ° C. or lower, 180 ° C. or lower, 170. It may be ℃ or less, 160 ℃ or less, 150 ℃ or less, 140 ℃ or less, 135 ℃ or less, 130 ℃ or less, 120 ℃ or less, or 110 ℃ or less. The drying time is not particularly limited, but may be, for example, 30 seconds or more, 40 seconds or more, 50 seconds or more, or 60 seconds or more, 150 seconds or less, 130 seconds or less, 110 seconds or less, or 90 seconds or less. You may.

The means for curing the coating film is not particularly limited, but ultraviolet curing is preferable. The irradiation amount of the energy radiation source is preferably 50 to 500 mJ / cm ² as the integrated exposure amount at the ultraviolet wavelength of 365 nm. When the irradiation amount is 50 mJ / cm ² or more, curing tends to proceed sufficiently, and the hardness of the antiglare layer (B) formed tends to increase. Further, if it is 500 mJ / cm ² or less, coloring of the formed antiglare layer (B) can be prevented.

As described above, a laminate of the light transmissive base material (A) and the antiglare layer (B) can be produced. This laminated body may be used as it is as the antiglare film of the present invention, or may be, for example, the antiglare film of the present invention formed by forming the other layer on the antiglare layer (B). The method for forming the other layer is not particularly limited, and is, for example, the same as or similar to the method for forming a general low refractive index layer, antireflection layer, high refractive index layer, hard coat layer, adhesive layer, or the like. Can be done with.

[3. Optical member and image display device]
The optical member of the present invention is not particularly limited, but may be, for example, a polarizing plate. The polarizing plate is also not particularly limited, but may include, for example, the antiglare film and the polarizer of the present invention, and may further contain other components. Each component of the polarizing plate may be bonded by, for example, an adhesive or an adhesive.

The image display device of the present invention is not particularly limited, and any image display device may be used, and examples thereof include a liquid crystal display device and an organic EL display device.

The image display device of the present invention is, for example, an image display device having the antiglare film of the present invention on the surface on the viewing side, and the image display device may have a black matrix pattern.

In the antiglare film of the present invention, for example, the light transmitting base material (A) side can be attached to an optical member used in an LCD via an adhesive or an adhesive. In addition, in this bonding, the surface of the light transmissive base material (A) may be subjected to various surface treatments as described above. As described above, according to the method for producing an antiglare film of the present invention, the surface shape of the antiglare film can be freely controlled in a wide range. Therefore, the optical properties that can be obtained by laminating the antiglare film with other optical members using an adhesive, an adhesive, or the like cover a wide range corresponding to the surface shape of the antiglare film. ..

Examples of the optical member include a polarizer or a polarizing plate. The polarizing plate generally has a transparent protective film on one side or both sides of the polarizing element. When the transparent protective films are provided on both sides of the polarizer, the transparent protective films on the front and back sides may be made of the same material or different materials. Polarizing plates are usually arranged on both sides of the liquid crystal cell. Further, the polarizing plates are arranged so that the absorption axes of the two polarizing plates are substantially orthogonal to each other.

The configuration of the polarizing plate on which the antiglare film is laminated is not particularly limited, but for example, the transparent protective film, the polarizer and the transparent protective film are laminated in this order on the antiglare film. Alternatively, the polarizer and the transparent protective film may be laminated in this order on the antiglare film.

The image display device of the present invention has the same configuration as the conventional image display device except that the antiglare film is arranged in a specific direction. For example, in the case of an LCD, it can be manufactured by appropriately assembling optical members such as a liquid crystal cell and a polarizing plate, and if necessary, each component such as a lighting system (backlight or the like) and incorporating a drive circuit.

According to the antiglare film of the present invention, for example, strong external light can be scattered and reflection can be suppressed, so that reflection can be suppressed even outdoors. Therefore, the image display device of the present invention can be suitably used as, for example, an outdoor public information display. However, the image display device of the present invention is not limited to this application, and can be used for any other application. Applications include, for example, OA devices such as personal computer monitors, laptop computers, and copy machines, mobile phones, watches, digital cameras, mobile information terminals (PDAs), portable devices such as portable game machines, video cameras, televisions, and microwave ovens. Home electrical equipment such as, back monitor, car navigation system monitor, in-vehicle equipment such as car audio, exhibition equipment such as information monitor for commercial stores, security equipment such as monitoring monitor, nursing monitor, medical monitor Nursing care / medical equipment, etc.

Next, examples of the present invention will be described together with comparative examples. However, the present invention is not limited by the following examples and comparative examples.

In the following examples and comparative examples, the number of copies of the substance is parts by mass (parts by weight) unless otherwise specified.

<Production Example 1> Preparation of Base Film A First, imidization was performed using a tandem type reaction extruder in which two extruders were arranged in series in the same manner as in Production Example 1 of JP2010-284840. A polymethyl methacrylate resin was produced. As the tandem type reaction extruder, both the first extruder and the second extruder used a same-direction meshing twin-screw extruder having a diameter of 75 mm and an L / D (ratio of the length L of the extruder to the diameter D) of 74. .. A constant weight feeder (manufactured by Kubota Co., Ltd.) was used to supply the raw material resin to the raw material supply port of the first extruder. The degree of decompression of each vent in the first extruder and the second extruder was −0.095 MPa. For the connection between the first extruder and the second extruder, a pipe having a diameter of 38 mm and a length of 2 m was used. A constant flow pressure valve was used as the internal pressure control mechanism for connecting the resin discharge port of the first extruder and the raw material supply port of the second extruder. Further, resin pressure gauges were provided at the outlet of the first extruder, the central portion of the connecting component between the first extruder and the second extruder, and the outlet of the second extruder. This resin pressure gauge can be used for adjusting the pressure in the component connecting the resin discharge port of the first extruder and the raw material supply port of the second extruder, or for determining the extrusion fluctuation.

The imidized polymethyl methacrylate resin was produced as follows. First, a polymethyl methacrylate resin (Mw: 105,000) as a raw material resin and a monomethylamine as an imidizing agent were put into the first extruder to produce an imide resin intermediate 1. At this time, the maximum temperature of the extruder was 280 ° C., the screw rotation speed was 55 rpm, the amount of the raw material resin supplied was 150 kg / hour, and the amount of monomethylamine added was 2.0 parts with respect to 100 parts of the raw material resin. Further, the pressure of the monomethylamine press-fitting portion of the first extruder was adjusted to 8 MPa by a constant flow pressure valve installed immediately before the raw material supply port of the second extruder. Next, the imide resin intermediate 1 was transferred into the second extruder, and the remaining imidization reaction reagent and by-products were devolatile at the rear vent and the vacuum vent. Then, a mixed solution of dimethyl carbonate and triethylamine was added as an esterifying agent to prepare an imide resin intermediate 2. At this time, the barrel temperature of the second extruder was 260 ° C., the screw rotation speed was 55 rpm, the amount of dimethyl carbonate added was 3.2 parts with respect to 100 parts of the raw material resin, and the amount of triethylamine added with respect to 100 parts of the raw material resin. 0.8 copies. Further, the esterifying agent was removed by venting, extruded from the strand die, cooled in a water tank, and then pelletized with a pelletizer to obtain the desired imidized polymethyl methacrylate resin. The imidization ratio of this imidized polymethyl methacrylate resin was 3.7%, and the acid value was 0.29 mmol / g.

Next, 100 parts by weight of the imidized polymethyl methacrylate resin and 0.62 parts by weight of a triazine-based ultraviolet absorber (trade name: T-712 manufactured by ADEKA CORPORATION) are mixed at 220 ° C. with a twin-screw kneader. Then, resin pellets were prepared. The resin pellets were dried at 100.5 kPa at 100 ° C. for 12 hours and extruded from a T-die at a die temperature of 270 ° C. using a single-screw extruder to form a film (thickness 160 μm). Further, the film was stretched in an atmosphere of 150 ° C. in the transport direction of the film to a thickness of 80 μm. Next, the film was stretched in an atmosphere of 150 ° C. in a direction orthogonal to the transport direction of the film to obtain a base film A ((meth) acrylic resin film) having a thickness of 40 μm. The light transmittance of the obtained base film A at a wavelength of 380 nm was 8.5%, the in-plane retardation Re was 0.4 nm, and the thickness direction retardation Rth was 0.78 nm. The moisture permeability of the obtained base material film A was ^61g / m 2 · 24hr. For the light transmittance, the transmittance spectrum was measured in the wavelength range of 200 nm to 800 nm using a spectrophotometer (device name: U-4100) manufactured by Hitachi High-Tech Co., Ltd., and the transmittance in the wavelength of 380 nm was read. .. The phase difference value was measured at a wavelength of 590 nm and 23 ° C. using the product name “KOBRA21-ADH” manufactured by Oji Measuring Instruments Co., Ltd. The water permeability was measured by a method according to JIS K 0208 under the conditions of a temperature of 40 ° C. and a relative humidity of 92%.

[Coating liquid 1]
Pentaerythritol triacrylate (PETA) (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name: Viscoat # 300, concentration 80%) 60 parts, 15-functional urethane acrylic oligomer (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: NK oligo UA-53H, Weight average molecular weight: 2300, concentration 100%) 40 parts, 4-hydroxybutyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name: 4-HBA, concentration 100%) 20 parts, leveling agent (manufactured by DIC, trade name: GRANDIC PC-4100) 1 part, photopolymerization initiator (BASF Japan, trade name: Irgacure 907), 5 parts, cross-linked acrylic styrene copolymer resin fine particles (Sekisui Kasei Co., Ltd., trade name: SSX1055QXE, weight average particles) 8 parts of diameter: 5.5 μm) and 2.5 parts of thickener (thixotropy-imparting agent, manufactured by Kunimine Kogyo Co., Ltd., trade name: Smecton SAN adjusted to 6% concentration with toluene) are mixed, and the solid content The coating solution 1 (composition for forming an antiglare layer) was prepared by diluting the mixture so that the concentration was 40% and the total amount of toluene and methyl ethyl ketone was 7: 3.

[Coating liquid 2]
The fine particles of the crosslinked acrylic styrene copolymer resin of the coating liquid 1 are coated in the same manner as the coating liquid 1 except that the fine particles of the crosslinked acrylic styrene copolymer resin having a weight average particle diameter of 3.0 μm are changed to 6 parts. Work solution 2 (composition for forming an antiglare layer) was prepared.

[Coating liquid 3]
The fine particles of the crosslinked acrylic styrene copolymer resin of the coating liquid 1 are coated in the same manner as the coating liquid 1 except that the fine particles of the crosslinked acrylic styrene copolymer resin having a weight average particle diameter of 8.0 μm are changed to 20 parts. Work solution 3 (composition for forming an antiglare layer) was prepared.

<Measurement method>
[Surface shape measurement]
A glass plate (thickness 1.3 mm) manufactured by Matsunami Glass Industry Co., Ltd. is attached to the surface of the antiglare film where the antiglare layer is not formed with an adhesive, and a high-precision fine shape measuring instrument (trade name; surf) is attached. The surface shape of the antiglare layer (B) was measured under the condition of a cutoff value of 0.8 mm using a coder ET4000 (manufactured by Kosaka Laboratory Co., Ltd.), and the maximum height and the average inclination angle were calculated. Further, the average values obtained by measuring the maximum height and the average inclination angle at arbitrary 10 points were defined as the maximum height Ry and the average inclination angle θa, respectively. The high-precision fine shape measuring instrument automatically calculates the maximum height Ry and the average inclination angle θa. The method for measuring and calculating the maximum height Ry and the average inclination angle θa is based on JIS B 0601 (1994 edition).

[Reflection]
(1) A black acrylic plate (manufactured by Mitsubishi Rayon Co., Ltd., thickness 2.0 mm) is attached to the surface of the antiglare film where the antiglare layer is not formed with an adhesive to eliminate the reflection on the back surface. Made.
(2) In an office environment where a display is generally used (about 1000 Lx), the sample is illuminated with a fluorescent lamp (three-wavelength light source) from a position 50 cm away in the front direction, and the antiglare property of the sample is adjusted in the front direction. It was visually determined from a position 50 cm away from the above according to the following criteria.

Judgment criteria ◎: Excellent anti-glare property, leaving no image of the outline of the reflected fluorescent lamp.
○: ◎ is inferior in anti-glare property, but it is possible to prevent reflection without any problem.
Δ: The anti-glare property is inferior to that of ○, but the outline of the fluorescent lamp is slightly blurred.
X: The outline of the fluorescent lamp is not blurred and is reflected clearly.

[Diagonal reflection]
Except that the fluorescent lamp was irradiated from a position 50 cm away from the front of the sample in a direction inclined by 30 °, and visually judged from a position 50 cm away from the front of the sample in a direction inclined by 30 ° according to the following criteria. Performed an oblique reflection test in the same manner as the reflection test.

Judgment criteria ◎: Excellent anti-glare property, leaving no image of the outline of the reflected fluorescent lamp.
○: ◎ is inferior in anti-glare property, but it is possible to prevent reflection without any problem.
Δ: The anti-glare property is inferior to that of ○, but the outline of the fluorescent lamp is slightly blurred.
X: The outline of the fluorescent lamp is not blurred and is reflected clearly.

[Film thickness t]
The maximum thickness of the antiglare layer (B) is measured at the same 10 points as the measurement point of the maximum height Ry by the high-precision fine shape measuring instrument (trade name; surf coder ET4000, manufactured by Kosaka Laboratory Co., Ltd.). did. The average value of the measured values of the maximum thickness at the 10 points was defined as the maximum thickness d of the antiglare layer (B). The value obtained by subtracting the maximum height Ry from the maximum thickness d was defined as the film thickness t of the antiglare layer (B). The high-precision fine shape measuring instrument automatically calculates the maximum thickness d and the film thickness t. Further, in the present embodiment and the comparative example, since the maximum thickness d is substantially equal to the weight average particle diameter of the fine particles, the value obtained by subtracting the maximum height Ry from the weight average particle diameter is approximately defined as the film thickness t. can do.

[Haze value]
The haze value is measured according to the haze (cloudiness) of JIS K 7136 (2000 version), using a haze meter (manufactured by Murakami Color Technology Research Institute Co., Ltd., product name "HM-150") to prevent glare. The sex film was set alone and measured.

[Example 1]
The coating liquid 1 was applied (coated) on one surface of the base material (light-transmitting base material (A)) of Production Example 1 to form a coating layer (coating layer). Then, the coating layer was heated at 90 ° C. for 1 minute and dried to form a coating film. Then, the coating film was cured by irradiating the coating film with ultraviolet rays having an integrated light intensity of 300 mJ / cm ² with a high-pressure mercury lamp to form an antiglare layer (B), thereby obtaining a target antiglare film. The maximum height Ry value of the antiglare layer (B) was 4.6 μm. Further, in this embodiment, the antiglare layer (B) is an antiglare hard coat layer. The same applies to each of the following Examples and Comparative Examples.

[Example 2]
By changing the thickness of the coating film, an antiglare film was obtained in the same manner as in Example 1 except that the maximum height Ry value of the antiglare layer (B) was set to 2.6 μm.

[Example 3]
By changing the thickness of the coating film, an antiglare film was obtained in the same manner as in Example 1 except that the maximum height Ry value of the antiglare layer (B) was set to 1.8 μm.

[Comparative Example 1]
By changing the thickness of the coating film, an antiglare film was obtained in the same manner as in Example 1 except that the maximum height Ry value of the antiglare layer (B) was set to 1.1 μm.

[Comparative Example 2]
Fine particles of crosslinked acrylic styrene copolymer resin (manufactured by Sekisui Plastics Co., Ltd., trade name: SSX1055QXE, average particle size: 5.5 μm) from the coating liquid 1 on the antiglare layer (A) of the antiglare film of Example 2. ) The coating liquid from which 8 parts were removed was overcoated again. Then, the overcoated layer was dried and cured by the same method as in Example 1 to form an antiglare layer. The maximum height Ry value of this antiglare layer was 0.64 μm.

[Comparative Example 3]
An antiglare film was obtained in the same manner as in Example 1 except that the coating liquid 1 was changed to the coating liquid 2 and the maximum height Ry value of the antiglare layer (B) was 1.5 μm.

[Comparative Example 4]
By changing the thickness of the coating film, an antiglare film was obtained in the same manner as in Comparative Example 3 except that the maximum height Ry value of the antiglare layer (B) was set to 1.1 μm.

[Comparative Example 5]
By changing the thickness of the coating film, an antiglare film was obtained in the same manner as in Comparative Example 3 except that the maximum height Ry value of the antiglare layer (B) was set to 2.4 μm. Next, on the antiglare layer (A) of this antiglare film, fine particles of crosslinked acrylic styrene copolymer resin from the coating liquid 1 (manufactured by Sekisui Plastics Co., Ltd., trade name: SSX1055QXE, average particle size: 5.5 μm). ) The coating liquid from which 8 parts were removed was overcoated again. Then, the overcoated layer was dried and cured by the same method as in Example 1 to form an antiglare layer. The maximum height Ry value of this antiglare layer was 0.55 μm.

[Example 4]
An antiglare film was obtained in the same manner as in Example 1 except that the coating liquid 1 was changed to the coating liquid 3 and the maximum height Ry value of the antiglare layer (B) was set to 6.9 μm.

[Example 5]
An antiglare film was obtained in the same manner as in Example 1 except that the coating liquid 1 was changed to the coating liquid 3 and the maximum height Ry value of the antiglare layer (B) was 4.5 μm.

[Example 6]
An antiglare film was obtained in the same manner as in Example 1 except that the coating liquid 1 was changed to the coating liquid 3 and the maximum height Ry value of the antiglare layer (B) was 2.6 μm.

[Example 7]
By changing the thickness of the coating film, an antiglare film was obtained in the same manner as in Example 4 except that the maximum height Ry value of the antiglare layer (B) was set to 1.8 μm.

[Comparative Example 6]
By changing the thickness of the coating film, an antiglare film was obtained in the same manner as in Example 4 except that the maximum height Ry value of the antiglare layer (B) was set to 1.2 μm.

[Comparative Example 7]
Fine particles of crosslinked acrylic styrene copolymer resin (manufactured by Sekisui Plastics Co., Ltd., trade name: SSX1055QXE, average particle size: 5.5 μm) from the coating liquid 1 on the antiglare layer (A) of the antiglare film of Example 6. ) The coating liquid from which 8 parts were removed was overcoated again. Then, the overcoated layer was dried and cured by the same method as in Example 1 to form an antiglare layer. The maximum height Ry value of this antiglare layer was 0.77 μm.

The film thickness t (thickness obtained by subtracting the maximum height of the convex portion of the unevenness from the maximum thickness of the antiglare layer (B)) and the maximum convex portion of the uneven portion on the outermost surface in Examples 1 to 7 and Comparative Examples 1 to 7 Table 1 below summarizes the height Ry, the average inclination angle θa of the unevenness on the outermost surface, the haze value, the reflection test result, and the oblique reflection test result.

As shown in Table 1 above, in Examples 1 to 7 in which Ry and θa satisfy the requirements of the present invention, reflection was suppressed. On the other hand, in Comparative Examples 2, 5 and 7 in which Ry and θa were outside the scope of the present invention, reflections in the front direction and the oblique direction were remarkable. Further, in Comparative Examples 1, 3, 4 and 6 in which θa satisfies the requirements of the present invention but Ry is outside the scope of the present invention, the reflection in the oblique direction was remarkable.

As described above, according to the present invention, it is possible to provide an antiglare film, an optical member, and an image display device in which glare is suppressed. According to the antiglare film of the present invention, for example, strong external light can be scattered and reflection can be suppressed, so that reflection can be suppressed even outdoors. Therefore, the present invention can be suitably used for an image display device such as an outdoor public information display. However, the present invention is not limited to this application and can be used in a wide range of applications.

This application claims priority based on Japanese application Japanese Patent Application No. 2019-075132 filed on April 10, 2019, and incorporates all of its disclosures herein.

10 Anti-glare film 11 Light-transmitting base material (A)
12 Anti-glare layer (B)
12a Resin layer 12b Particles 12c Thixotropy-imparting agent 13 Other layers Ry Maximum height of uneven protrusions on the outermost surface d Maximum thickness other than the light transmissive substrate (A) D Particle diameter of fine particles Ry'Anti-glare layer (B) ) Maximum height of the uneven convex portion d'Maximum thickness of the antiglare layer (B) t Film thickness of the antiglare layer (B) (d'-Ry')

Claims (13)

1. An antiglare film in which an antiglare layer (B) is laminated on a light transmissive base material (A).
   Unevenness is formed on the outermost surface of the antiglare film on the antiglare layer (B) side.
   An antiglare film characterized in that the unevenness satisfies the following mathematical formulas (1) and (2).
   
   Ry ≧ 1.7 (1)
   θa ≧ 0.7 (2)
   
   In the mathematical formula (1), Ry is the maximum height [μm] of the convex portion of the unevenness.
   In the mathematical formula (2), θa is the average inclination angle [°] of the unevenness.
2. The antiglare film according to claim 1, wherein the antiglare layer (B) contains fine particles.
3. Concavities and convexities are formed on the surface of the antiglare layer (B) opposite to the light transmissive base material (A).
   The antiglare film according to claim 2, wherein the weight average particle diameter of the fine particles is larger than the thickness obtained by subtracting the maximum height of the convex portion of the unevenness from the maximum thickness of the antiglare layer (B).
4. The antiglare film according to claim 2 or 3, wherein the weight average particle diameter of the fine particles is in the range of 4 to 9 μm.
5. The antiglare according to any one of claims 1 to 4, wherein another layer is further laminated on the surface of the antiglare layer (B) opposite to the light transmissive base material (A). Sex film.
6. An antiglare film in which an antiglare layer (B) and other layers are laminated in the above order on a light transmissive base material (A).
   Unevenness is formed on the outermost surface of the other layer,
   An antiglare film characterized in that the unevenness satisfies the following mathematical formulas (1) and (2).
   
   Ry ≧ 1.7 (1)
   θa ≧ 0.7 (2)
   
   In the mathematical formula (1), Ry is the maximum height [μm] of the convex portion of the unevenness.
   In the mathematical formula (2), θa is the average inclination angle [°] of the unevenness.
7. The antiglare layer (B) forming step of forming the antiglare layer (B) on the light transmissive base material (A) so as to satisfy the mathematical formulas (1) and (2) is included.
   The antiglare layer (B) forming step includes a coating step of applying a coating liquid on the light transmissive base material (A) and drying the coated coating liquid to form a coating film. Including the coating film forming step
   The method for producing an antiglare film according to any one of claims 1 to 6, wherein the coating liquid contains a resin and a solvent.
8. The manufacturing method according to claim 7, wherein the antiglare layer (B) forming step further includes a curing step of curing the coating film.
9. The production method according to claim 7 or 8, wherein the coating liquid contains fine particles.
10. An optical member including the antiglare film according to any one of claims 1 to 6.
11. The optical member according to claim 10, which is a polarizing plate.
12. An image display device including the antiglare film according to any one of claims 1 to 6 or the optical member according to claim 10 or 11.
13. The image display device according to claim 12, which is a public information display.

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