JP4384506B2 - Antiglare film - Google Patents

Description

  The present invention relates to an antiglare film used for various displays (such as a liquid crystal display), a manufacturing method thereof, and a display device including the antiglare film.

  In recent years, various displays such as liquid crystal displays, plasma displays, organic EL (electroluminescence) displays, inorganic EL displays, and FED (field emission displays) have been developed. In particular, liquid crystal displays have made remarkable progress as display devices in television (TV) applications or moving image display applications, and are rapidly spreading. For example, the development of high-speed liquid crystal materials and the improvement of driving methods such as overdrive have overcome the conventional video display that LCDs were not good at, and production technology innovations that responded to larger displays Yes.

  In these displays, in applications such as televisions and monitors that place importance on image quality, and video cameras that are used outdoors with strong external light, the surface is usually treated to prevent reflection of external light. It is. One of the techniques is anti-glare treatment, and for example, the surface of a liquid crystal display is usually subjected to anti-glare treatment. The anti-glare treatment has an effect of blurring the reflected image by scattering the surface reflected light by forming a fine uneven structure on the surface. Therefore, unlike the clear antireflection film, the antiglare film does not reflect the shape of the viewer and the background, and thus the reflected light is unlikely to disturb the image.

  For example, Japanese Patent Application Laid-Open No. 7-27920 (Patent Document 1) discloses a polyethylene terephthalate film that is attached to a polarizing plate used on the surface of various displays such as word processors, computers, and televisions, particularly a liquid crystal display. A polyethylene terephthalate film that has been antiglare treated by shaping a shaped film having fine irregularities is disclosed. In this document, an ionizing radiation curable resin composition is coated on polyethylene terephthalate, and then fine irregularities are formed on the surface of the coated ionizing radiation curable resin composition in an uncured state. A laminated film having a mat-like shape is laminated, and then the laminated coating is irradiated with ionizing radiation to completely cure the coated film, and then the mat-shaped shaped film is completely cured. It is described that an antiglare layer having fine irregularities formed on the surface thereof is obtained by peeling from the surface.

  Japanese Patent Application Laid-Open No. 11-337734 (Patent Document 2) discloses an antiglare treatment layer having irregularities formed on the surface as a surface treatment layer formed on the surface of a polarizing film suitable as a material for a liquid crystal cell. . According to this document, the anti-glare layer is formed by applying a dispersion of fine particles having a high refractive index in a resin solution by spin coating or after applying only an acrylic resin by spin coating or the like. It is described that the surface is formed directly by mechanically or chemically unevenly forming the surface.

  JP 2001-215307 A (Patent Document 3) discloses an antiglare layer containing transparent fine particles having an average particle diameter of 15 μm in a film having a thickness twice or more the average particle diameter, Among them, an antiglare layer is disclosed in which the transparent fine particles are unevenly distributed on one side in contact with air to form a fine concavo-convex structure.

  However, in these antiglare films, light scattering on the surface increases due to the unevenness of the film surface for imparting antiglare properties, and the scattered light is mixed into a portion that originally appears black and becomes whitish. That is, in places where the outside light is strong, the screen is generally whitish and lacks a sense of contrast. In particular, in television (TV) applications, a recent home theater boom has become a tailwind, and an image with a strong contrast feeling in which black has been tightened is required.

  Therefore, an increasing number of liquid crystal TVs have a clear surface without being subjected to anti-glare treatment. However, viewers with a clear surface and the reflection of the background became noticeable, which often hindered high-quality images. In particular, in the large-sized display due to the above-mentioned home theater boom, contrast deterioration and reflection are severe, and it is difficult to satisfy both characteristics.

On the other hand, in Japanese Patent Application Laid-Open No. 2003-177207 (Patent Document 4), an uneven surface having an average height of the contour curve element of 0.1 to 30 μm is formed, and the convex portion per 0.01 mm ^{2 of the} uneven surface. The number of the antireflection film having a resin layer of 1-1000, the parallel surface having an inclination angle of 0-5 ° with respect to the antireflection film surface of the uneven surface occupies 15-100%, the parallel An antireflection film is disclosed in which 15 to 100% of the surface is formed as a convex portion. In this document, in order to improve the antireflection performance of the polarizing plate and the transmission clarity of the film, the convex portions on the surface have a planar structure parallel to the film. However, in this film, the external light reflected by the convex portions is not scattered because the convex portions are flat, and is reflected as regular reflection light, so that an image is reflected and the properties as an antiglare film are low.
JP-A-7-27920 (Claims 1 and 3, paragraph numbers [0001] [0020]) JP 11-337734 A (Claims 1, 4 and 8, paragraph number [0001]) JP 2001-215307 A (Claim 1, paragraph number [0012]) JP 2003-177207 A (Claim 1, paragraph numbers [0001] [0024])

  Therefore, an object of the present invention is to prevent glare on a display even under strong external light and to display an image with high contrast with reduced whiteness and whitening (white blurring). It is in providing a conductive film and its manufacturing method.

  Another object of the present invention is to provide an antiglare film that can reduce whitening around specular reflection and a method for producing the same.

  Still another object of the present invention is to provide an antiglare film capable of suppressing white floating in a black display image and capable of displaying an image with a strong contrast feeling in which black is tightened, and a method for manufacturing the same, even for a large display. There is.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that the cause of the whitishness of the display image is a region having an inclination angle of 2.5 to 7.5 ° on the antiglare film surface having an uneven surface. If this area is reduced, it is possible to achieve both reflection and image contrast. Further, if the area with a smaller inclination angle of less than 2.5 ° is set to 50% or more, the anti-glare effect is improved. On the other hand, it has been found that the region exceeding the inclination angle of 10 ° has a low relationship with the whitish color, and the present invention has been completed.

  That is, the antiglare film of the present invention has a surface with a fine concavo-convex structure, and the area ratio of the region S2 having an inclination angle of 2.5 to 7.5 ° with respect to the surface is 20 with respect to the entire surface. % Or less (for example, 18% or less). In the antiglare film, the area ratio of the region S1 whose inclination angle with respect to the surface is less than 2.5 ° may be 50% or more with respect to the entire surface. The area ratio of the region S4 whose inclination angle with respect to the surface is 10 ° or more may be 1% or more with respect to the entire surface. Further, the average apex distance Sm may be about 20 to 150 μm (for example, 25 to 130 μm). The ratio Rz / Sm between the ten-point average roughness Rz and the average apex distance Sm may be about 0.005 to 0.02. The anti-glare film has a reflected scattered light gain of 0.1 or more with respect to a standard white plate in an angle range of 10 to 17 ° from the normal to the surface, and a half-value angle of the reflected scattered light gain of 2 to 2. It may be about 5 °. Furthermore, when a region where the inclination angle with respect to the surface is more than 7.5 ° and less than 10 ° is S3, the area ratio between the region S2 and the other regions (the sum of S1, S3, and S4) is, for example, S2 /(S1+S3+S4)=0.1/99.9 to about 20/80, and the ratio of the area of the region S1 to the total area of the regions S3 and S4 is, for example, S1 / (S3 + S4) = 99. / 1 to 60/40 may be sufficient.

  Examples of the antiglare film include alicyclic olefin resins, vinyl acetate resins, (meth) acrylic resins, styrene resins, polyester resins, polycarbonate resins, polyamide resins, cellulose derivatives, and epoxy (meta). ) Transparent resin such as acrylate (in particular, transparent resin such as (meth) acrylic resin, styrene resin, cellulose derivative, epoxy (meth) acrylate).

  The present invention also includes a method for producing the antiglare film by phase-separating a plurality of resins. Furthermore, the present invention includes a display device provided with the antiglare film.

  In the present invention, since the inclination angle of the concavo-convex structure of the antiglare film is controlled, reflection on the display can be prevented even under strong external light, and whitishness and whitening can be reduced. An image with high contrast can be displayed. In particular, the whitening around the regular reflection can be reduced. Furthermore, even with a large display, white floating in a black display image can be suppressed, and an image with a strong contrast with black tightened can be displayed.

  The anti-glare film has a property of preventing reflection by forming a concavo-convex structure on the surface, but has a property that the reflected light increases due to the concavo-convex structure and the image becomes whitish. Therefore, if the inclination angle of the concavo-convex structure with respect to the film surface is simply reduced, the scattering angle of the reflected light is also reduced, and thus whitening tends to be considered to be eliminated by reducing the inclination angle. However, when the inclination angle is decreased, the white floating portion around the regular reflection becomes more whitish. Further, the cause of the white floating is the inclination angle 2 in the inclination of the uneven surface of the antiglare film. It was found to be reflected light from a region of 5 to 7.5 °. Therefore, in the present invention, the inclination angle of the concavo-convex structure on the surface is controlled for the antiglare film having the surface of the fine concavo-convex structure.

  In the antiglare film of the present invention, the area ratio of the region S2 having an inclination angle of 2.5 to 7.5 ° with respect to the surface is preferably small, and is 20% or less with respect to the entire surface (for example, 0.1 to 0.1). 20%), preferably 18% or less (for example, 0.1 to 18%), more preferably 15% or less (for example, 1 to 15%), and particularly preferably 10% or less (for example, 1 to 10%). ) In the present invention, when the area ratio of the region S2 is within this range, whitishness can be eliminated while preventing reflection. In particular, when the area ratio of the region S2 is 10% or less, the whitish characteristic of the conventional antiglare film is hardly seen.

  In the present invention, in addition to the region S2, the surface of the antiglare film may be formed according to the inclination angle, region S1: less than 2.5 °, region S3: more than 7.5 ° and less than 10 °, region S4: Although it is divided into four types of regions of 10 ° or more, the area ratio of each region can be measured as follows.

  That is, the inclination angle of each region with respect to the surface is obtained by dividing the surface of the concavo-convex structure into 0.1 to 10 μm (preferably 0.3 to 5 μm, more preferably 0.5 to 2 μm, usually about 1 μm) square microregions. To measure. The apparatus for measuring the tilt angle is not particularly limited as long as it is an apparatus system that can measure the uneven structure in three dimensions. For example, an atomic force microscope system, a stylus step measurement system, a confocal laser microscope analysis system, etc. Is mentioned.

  A specific method for measuring the tilt angle by the measurement system is, for example, as follows. First, the concavo-convex structure on the film surface is analyzed, and the analysis result of the concavo-convex structure on the surface is divided into minute regions that are regarded as substantially flat. Next, it can obtain | require by measuring the inclination-angle of each micro area | region, and calculating as an area ratio in the total area of an uneven | corrugated plane. Note that the minute region regarded as a substantially flat surface here is, for example, a minute region divided into the size of the range in the case of a gentle uneven structure, or even if divided into a larger size This is an area where the distribution of the inclination angle within the area falls within ± 0.1 °. In the case of an antiglare film in which a fine particle filler is dispersed, the periphery of the fine particles is preferably a region divided by sides of about 0.2 times the particle size of the fine particles.

  In the present invention, the inclination angle is expressed as an angle of 0 to 90 ° with respect to the surface regardless of the direction of measurement. In addition, the regions S1 to S4 may be either a convex portion or a concave portion. In the present invention, for the sake of convenience, the case of 0 ° is also included in the inclination.

  In the antiglare film, the area ratio of the region S1 whose inclination angle with respect to the surface is less than 2.5 ° (0 ° or more and less than 2.5 °) is 50% or more (for example, 50 to 100). %), Preferably 70% or more (for example, 70 to 99%), more preferably 80% or more (for example, 80 to 99%), and particularly preferably about 90% or more (for example, 90 to 99%). is there. However, since the antiglare film has a fine concavo-convex structure, when the tilt angle is 0 °, the area ratio of S1 is not 100%. When the area ratio of the S1 region is within this range, a good anti-glare effect is obtained and white floating, particularly white floating in black display, is suppressed. Furthermore, the more the area S1, the more the texture close to the clear surface can be obtained. On the other hand, when it is desired to avoid the reflection as much as possible, the area S1 is preferably as small as possible. Therefore, the ratio of the region S1 is preferably selected from the above range according to the purpose and application.

  In the antiglare film, the area ratio of the region S4 having an inclination angle of 10 ° or more (10 to 90 °) with respect to the surface is preferably 1% or more (for example, 1 to 50%) with respect to the entire surface. Is about 1 to 30%, more preferably about 1 to 10% (particularly 1 to 5%). When the area ratio of the region S4 is in the above range, the antiglare effect is high. Note that the area S4 having a large inclination angle is relatively unrelated to the whitishness and whitening of the screen, and therefore the area ratio of the area S4 is preferably large from the viewpoint of preventing reflection. Note that the area ratio of the regions S1 to S4 is S1 + S2 + S3 + S4 = 100%.

  Regarding the area ratio of the regions S1 to S4, the area ratio between the region S2 and other regions (the sum of S1, S3 and S4) is, for example, S2 / (S1 + S3 + S4) = 0.1 / 99.9 to 20 / 80, preferably 0.1 / 99.9 to 18/82, more preferably about 1/99 to 15/85 (particularly 1/99 to 10/90).

  The ratio of the area of the region S1 to the total area of the regions S3 and S4 is, for example, S1 / (S3 + S4) = 99/1 to 60/40, preferably 98.5 / 1.5 to 50/50, more preferably Is about 98/2 to 30/70 (particularly 98/2 to 10/90).

  The area ratio between the region S3 and the region S4 is, for example, S3 / S4 = 1/99 to 90/10, preferably 10/90 to 70/30, and more preferably about 30/70 to 60/40.

  As the height of the concavo-convex structure of the treatment film, the ten-point average roughness based on JIS B 0601 is, for example, 0.1 to 3, preferably 0.15 to 2, and more preferably 0.2 to 1 ( In particular, it is about 0.3 to 0.9).

  Further, the ratio (Rz / Sm) between the average apex distance Sm and the ten-point average roughness Rz is, for example, 0.005 to 0.02, preferably 0.006 to 0.018, and more preferably 0.006. About 0.015.

  The values of Rz and Sm can be calculated from the analysis results obtained by the apparatus system that can measure the uneven structure in three dimensions.

  In the antiglare film, the angle range where the gain of reflected and scattered light is 0.1 or more is, for example, about 10 to 17 °, preferably about 11 to 17 °, and more preferably about 12 to 16.5 °. The reflected light having a gain of 0.1 or more is reflected light that lowers the contrast of the screen and deteriorates the whiteness of the screen. When the angle range is 17 ° or less, an image with good whiteness and high contrast can be displayed.

  Furthermore, in the antiglare film, the half-value angle (half-value width) of the reflected and scattered light is, for example, 2 to 5 °, preferably 2.2 to 4.8 °, more preferably 2.5 to 4. It is about 5 °. Here, the half-value angle means an angle range (half-value angular width) indicating a gain that is equal to or greater than the half value with respect to the maximum gain value of the reflected scattered light. When the half-value angle is within this range, reflection can be prevented and whitening due to scattering of reflected light can be suppressed.

  The gain of the reflected scattered light means the brightness of the reflected scattered light with respect to the standard white plate, and is a relative value when the reflected scattered light of the standard white plate is 1. For the measurement of reflected / scattered light, for example, a measuring system (for example, a variable angle photometer manufactured by Murakami Color Research Laboratory) that can change the light receiving angle of the light receiver and can measure the light intensity at any time can be used. . As a method for measuring the reflected and scattered light, for example, using such an apparatus, the incident light angle is normal to the antiglare film (or a film equipped with the antiglare film) (perpendicular to the film surface). A light source (preferably a laser light source, etc.) that is sufficiently narrowed so that the resolution is 1 ° or less from the line), is incident on the film, the angle of the light receiver is changed, and the luminous intensity of the surface reflected light The method of measuring can be used. The light receiving angle is set to 0 ° at a position 10 ° from the normal so that the reflected light is substantially symmetrical about 0 ° (normal). In addition, by applying black ink to the back side of the film, the film is processed in advance so that the reflected light is only from the surface of the antiglare film.

  The antiglare film having such properties is not particularly limited as long as it is formed of a transparent material, and may be composed of an inorganic substance (glass, silica, alumina, etc.), but usually at least It is made of transparent resin. Further, it may be composed of a plurality of components, for example, a combination of a plurality of transparent resins, an inorganic substance (for example, inorganic particles such as glass, alumina, aluminum hydroxide, mica, talc, montmorillonite, and clay) A combination with a transparent resin may be used. Further, the transparent resin may contain a non-transparent resin, a non-transparent inorganic substance, or the like as long as the transparency is not impaired. Of these, an antiglare film composed of a transparent resin or a combination of a plurality of transparent resins is preferable.

  Transparent resins include, for example, thermoplastic resins [cellulose derivatives, olefin resins (including alicyclic olefin resins), halogen-containing resins, vinyl alcohol resins, organic acid vinyl ester resins, (meth) acrylic resins. Styrene resin, polyester resin, polyamide resin, polycarbonate resin, polyether resin, polysulfone resin, thermoplastic polyurethane resin, polysulfone resin, polyphenylene ether resin, etc.], rubber or thermoplastic elastomer [polybutadiene, Diene rubber such as polyisoprene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, acrylic rubber, urethane rubber, silicone rubber, etc.], heat or photo-curing resin or precursor [epoxy resin, unsaturated polyester resin Diallyl phthalate resins, silicone resins, polyurethane resins, epoxy (meth) acrylate, allyl glycidyl ether, urethane (meth) acrylate, polyester (meth) acrylate, etc.] and the like. These transparent resins can be used alone or in combination of two or more.

Among these transparent resins, alicyclic olefin resins, vinyl acetate resins, (meth) acrylic resins, styrene resins, polyester resins, polycarbonate resins, polyamide resins, cellulose derivatives, and other thermoplastic resins, Thermal or photo-curable resins such as epoxy (meth) acrylate and allyl glycidyl ether, especially styrene resins [polystyrene, styrene-methyl methacrylate copolymer, styrene-acrylonitrile copolymer (AS resin), styrene-butadiene Copolymer, etc.], (meth) acrylic resin [poly (meth) methyl acrylate, etc.], cellulose derivatives [cellulose acetate (cellulose diacetate, cellulose triacetate, etc.), cellulose propionate, cellulose butyrate, cellulose acetate Propionate, cellulose C _1-6 organic acid esters such as cellulose acetate butyrate, epoxy (meth) acrylate [epoxycycloalkyl C _5-8 alkenyl (meth) acrylates such as epoxy cyclohexenyl (meth) acrylate, glycidyl (meth) An acrylate etc.] etc. are preferable.

  The thickness of the antiglare film can be selected from a range of about 1 to 500 μm, preferably 3 to 300 μm, more preferably about 5 to 200 μm (particularly 10 to 100 μm).

  If necessary, the antiglare film may have an antistatic layer (for example, a conductive thin film made of a photocurable resin containing a conductive agent or a hydrophilic component), an antireflection layer ( A thin film such as a low refractive index thin film made of a fluororesin or the like may be formed. The thickness of these thin films is, for example, about 0.01 to 10 μm, preferably about 0.03 to 1 μm, and more preferably about 0.05 to 0.1 μm.

The production method of the antiglare film of the present invention is not particularly limited, and fine particle filler (organic particles such as the inorganic particles, crosslinked acrylic resin, crosslinked polystyrene resin particles, etc.) is dispersed in the transparent resin. A method for forming a concavo-convex structure may be used, but from the viewpoint of simplicity, a method for forming a concavo-convex structure by phase separation of a plurality of resins, a laser beam (for example, YAG laser, CO ₂ laser) , A method of forming a concavo-convex structure by processing with a laser beam such as an Ar laser or an excimer laser, in particular an excimer laser beam, or a plate having a concavo-convex structure having a predetermined inclination angle is prepared and transferred to a substrate film or the like A method of forming an uneven structure (stamping method) or the like is preferable. The production method may be a method of molding a resin composition containing the transparent resin or the like, but from the viewpoint of simplicity, the transparent substrate (for example, the transparent material, particularly the transparent resin). A method of forming a concavo-convex structure by applying a resin composition containing the transparent resin or the like on a base material constituted of Among these methods, a method of forming (inducing) the concavo-convex structure by phase-separating a plurality of resins is particularly preferable.

  As a manufacturing method for phase-separating a plurality of resins, for example, a method in which a plurality of incompatible polymers are dissolved in a solvent, and a liquid-liquid phase separated solution is applied to a sea-island structure and dried, or a common solvent is used. And a method of forming a concavo-convex structure by applying a solution in which a plurality of incompatible polymers are compatible with each other and performing phase separation (spinodal decomposition) upon drying. In these methods, a thermal or photopolymerizable component (reactive or photopolymerizable component such as a polymerizable oligomer and / or monomer) is used together with or in place of the polymer, and after film formation, an active energy ray ( It may be polymerized and cured by irradiation with ultraviolet rays, electron beams, or the like.

  Examples of the polymerizable oligomer include epoxy (meth) acrylate, polyurethane (meth) acrylate, and polyester (meth) acrylate. Examples of the polymerizable monomer include monofunctional monomers such as alkyl (meth) acrylate and vinyl pyrrolidone, alkylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, Examples thereof include polyfunctional (meth) acrylates such as dipentaerythritol hexa (meth) acrylate.

  The ratio (weight ratio) between the polymer and the polymerizable component can be selected from the range of the former / the latter = 100/0 to 0.1 / 99.9, for example, 80/20 to 0.5 / 99.5. The ratio is preferably about 70/30 to 1/99, more preferably about 50/50 to 3/97 (particularly 70/30 to 5/95). In the polymerizable component, the ratio (weight ratio) between the oligomer and the monomer can be selected from the range of the former / the latter = 99/1 to 0/100, for example, 90/10 to 5/95, preferably 80 / It is about 20 to 10/90, more preferably about 70/30 to 20/80.

  Moreover, a solvent can be suitably selected according to the kind of a polymer or the said polymeric component, You may add a reaction initiator, a hardening | curing agent, etc. suitably. The distribution of the inclination angle of the concavo-convex structure can be adjusted by appropriately selecting the drying time, the curing time, the polymer, the polymerizable component, and the type and amount of the additive. In particular, in the method of forming a concavo-convex structure by spinodal decomposition (wet spinodal decomposition), phase separation occurs due to spinodal decomposition in the process of evaporation or removal of the solvent by drying, etc., and the interphase distance is compared. It becomes easy to form the structure which becomes regular regularity and has a specific inclination angle.

  The antiglare film of the present invention is used in various applications that require antiglare and light scattering properties, such as a liquid crystal display (LCD) device, a plasma display device, a display device with a touch panel, an organic EL display device, and an inorganic EL device. It can be used for display devices such as display devices and FED devices. The anti-glare film of the present invention has high anti-glare properties, prevents reflection of external light, and has a high contrast on the display surface. The liquid crystal display device is particularly preferably used.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In addition, the evaluation method at the time of mounting an anti-glare film | membrane in a liquid crystal display device is shown below.

[Mounting evaluation of anti-glare film]
The antiglare films obtained in the examples and comparative examples were respectively mounted on the surface of a VA (vertical alignment) type LCD panel having a front luminance of 450 cd / m ² , a contrast of 400 to 1, 20 type, and a resolution of 60 ppi for reflection. Reflection of light, whiteness (sink of black display), clarity of characters and images were visually evaluated according to the following criteria.

(Reflection)
○: No reflection Δ: There is a slight reflection ×: The reflection is intense.

(White taste)
A: The black display appears clear. B: The black display appears slightly white. Δ: The black display appears white. ×: The black display appears white.

(Clarity of text and images)
◎: Visible clearly ○: Visible almost clearly △: Visible ×: Difficult to see

Example 1
2 parts by weight of cellulose acetate propionate (manufactured by Eastman Chemical Co., CAP482-20), reactive oligomer [(meth) acrylic acid- (meth) acrylic acid ester copolymer, 3,4 -Compound to which epoxycyclohexenylmethyl acrylate was added; Daicel UCB (UCB), Cyclomer P] 15.2 parts by weight, dipentaerythritol hexaacrylate (DPHA) 15.8 parts by weight, photopolymerization 1.25 parts by weight of an initiator (manufactured by Ciba Specialty Chemicals, Irgacure 184) is dissolved in 68 parts by weight of a mixed solvent (methyl ethyl ketone / butanol (weight ratio) = 7.5 / 2.5). A solution was made. This solution was coated on a cellulose triacetate (TAC) film having a thickness of 80 μm with a wire coater # 24, and dried with warm air in an explosion-proof oven at 80 ° C. for 2 minutes. The resulting film had a fine concavo-convex structure formed on the surface by phase separation accompanying drying. This film was irradiated with ultraviolet rays from a metal halide lamp for about 30 seconds to produce a film having a concavo-convex structure on the surface.

  An antistatic coating material (a photocurable antistatic agent, manufactured by JSR Corporation, Desolite KZ6805) is applied to the surface having an uneven structure of the film with a wire coater # 8 so that the average thickness after drying becomes 0.15 μm. After being dried, it was cured by irradiating with ultraviolet rays from a metal halide lamp for about 30 seconds. Furthermore, a fluororesin solution (manufactured by JSR Corporation, Opstar TT1006) was applied to the surface with a wire coater # 8 so that the average thickness after drying was 0.09 μm to form an antiglare film.

  This antiglare film had a total light transmittance of 93.4%, a haze of 2.2%, and a gloss (angle of 60 °) of 118. When the surface uneven structure of the antiglare film was measured with an atomic force microscope, it had a comparatively gentle uneven shape. A three-dimensional shape profile by this measurement is shown in FIG. Furthermore, a laser micrograph (10x objective) of this antiglare film is shown in FIG. The average apex distance Sm was 67 μm, and the ten-point average roughness Rz was 0.45 μm. Next, this uneven surface is divided into 2 μm square microregions, the inclination angle is calculated for each, and the overall distribution is calculated. In addition, the same distribution was obtained when divided into 0.5 μm square microregions. Moreover, the result measured with the surface roughness shape measuring device (Tokyo Seimitsu Co., Ltd., Surfcom 1400A-3DF) was also the same.

  This anti-glare film is equipped on a cellulose triacetate (TAC) film with a black coating on the back, and the reflected and scattered light is measured with a light scattering measurement device (Murakami Color Research Laboratory, variable angle photometer GP-200). did. The incident light angle was set to −10 ° from the normal line of the film, a white light source with a diameter of 5 mm was incident on the film, the light receiver was turned, and the surface reflected scattered light was measured. The light receiving angle is set to 0 ° at a position 10 ° from the film normal so that the reflected light is substantially symmetric about 0 °. The measurement results are shown in FIG. In the figure, the vertical axis represents the luminous intensity and is shown as the gain of the reflected scattered light (relative value where the reflected light of the standard white plate is 1). From this measurement result, the half-value angle was 3 °, and the angle range with a gain of 0.1 or more was 13 °. The results are shown in Table 1. Furthermore, Table 1 shows the results of evaluating the characteristics of the antiglare film mounted on a liquid crystal display device.

Example 2
Cellulose acetate propionate (manufactured by Eastman Chemical Co., CAP482-20) 2.5 parts by weight, reactive oligomer (Daicel UCB Co., Ltd., Cyclomer P) 14.2 parts by weight, dipenta 15.8 parts by weight of erythritol hexaacrylate (DPHA) and 1.25 parts by weight of a reaction initiator (manufactured by Ciba Specialty Chemicals, Irgacure 184) are mixed solvent (methyl ethyl ketone / butanol / propylene glycol monomethyl ether (weight ratio) = 7) 0.5 / 2 / 0.5) dissolved in 68 parts by weight to prepare a transparent and uniform solution. This solution was applied onto a cellulose triacetate (TAC) film having a thickness of 80 μm with a wire coater # 24 and dried in warm air at 70 ° C. for 3 minutes in an explosion-proof oven. The resulting film had a fine concavo-convex structure formed on the surface by phase separation accompanying drying. This film was irradiated with ultraviolet rays from a metal halide lamp for about 30 seconds to produce a film having a concavo-convex structure on the surface.

  An antistatic coating material (Desolite KZ6805, manufactured by JSR Corporation) was applied to the surface of this film having a concavo-convex structure with a wire coater # 8 so that the average thickness after drying was 0.15 μm. It was cured by irradiating with ultraviolet rays from a lamp for about 30 seconds. Further, on this surface, a fluororesin solution (manufactured by JSR Corporation, Opstar TT1006) was applied with a wire coater # 8 so that the average thickness after drying was 0.09 μm to form an antiglare film. .

  This antiglare film had a total light transmittance of 91.6%, a haze of 4.8%, and a gloss (angle of 60 °) of 85. As in Example 1, the surface irregularities of this antiglare film were measured and analyzed. The irregularities were comparatively gentle, with an average apex distance Sm of 68 μm and a ten-point average roughness Rz of 0.88 μm. It was. The three-dimensional shape profile of this antiglare film is shown in FIG. Furthermore, Table 1 shows the result of calculating the inclination angle distribution of the uneven surface when divided into minute areas of 2 μm square. Similarly to Example 1, FIG. 6 and Table 1 show the results of measuring the reflected and scattered light using a goniophotometer. Furthermore, the antiglare film is mounted and the evaluation results are shown in Table 1.

Example 3
A solution to be coated on a cellulose triacetate (TAC) film was prepared by using 2.4 parts by weight of cellulose acetate propionate (manufactured by Eastman Chemical Co., CAP482-20), a reactive oligomer (manufactured by Daicel UCB (UCB)). In addition, an antiglare film was formed in the same manner as in Example 2 except that 13.4 parts by weight of cyclomer P) and 16.3 parts by weight of dipentaerythritol hexaacrylate (DPHA) were dissolved. This antiglare film had a total light transmittance of 93.1%, a haze of 7.2%, and a gloss (angle of 60 °) of 82. As in Example 1, the surface unevenness shape of this antiglare film was measured and analyzed. As a result, the unevenness was relatively gentle, the average apex distance Sm was 75 μm, and the ten-point average roughness Rz was 0.84 μm. It was. Furthermore, Table 1 shows the result of calculating the inclination angle distribution of the uneven surface when divided into minute areas of 2 μm square. Similarly to Example 1, FIG. 6 and Table 1 show the results of measuring the reflected and scattered light using a goniophotometer. Furthermore, the antiglare film is mounted and the evaluation results are shown in Table 1.

Comparative Example 1
Crosslinked acrylic fine particles (average particle size 3 μm, dispersed particle size / average particle size = 1.1, refractive index 1.49) and crosslinked acrylic fine particles (average particle size 3.5 μm, dispersed particle size / average particle size = 1. 1 and a refractive index of 1.49) were mixed at a ratio of 97: 3 (weight ratio), dispersed in pentaerythritol triacrylate (PETA), and diluted with ethyl acetate. The coating solution was coated and dried to an average thickness of 2.8 μm, and then irradiated with UV to form an uneven structure. A fluororesin solution (manufactured by JSR Co., Ltd., OPSTAR TT1006) was applied to the surface of the uneven film with a wire coater # 8 so that the average thickness after drying was 0.1 μm to form an antiglare film. . This antiglare film had a total light transmittance of 93%, a haze of 40%, and a gloss (angle of 60 °) of 90. As in Example 1, when the surface unevenness shape of this antiglare film was measured and analyzed, the average apex distance Sm was 137 μm, and the ten-point average roughness Rz was 1.03 μm. Furthermore, Table 1 shows the result of calculating the inclination angle distribution of the uneven surface when divided into small areas of 0.3 μm square. Similarly to Example 1, FIG. 6 and Table 1 show the results of measuring the reflected and scattered light using a goniophotometer. Furthermore, the antiglare film is mounted and the evaluation results are shown in Table 1.

Comparative Example 2
Crosslinked acrylic fine particles (average particle size 3 [mu] m, dispersed / average diameter = 1.2, refractive index 1.4 9) was diluted with ethyl acetate is dispersed in pentaerythritol triacrylate (PETA). This was coated, dried, made 2.8 μm thick, and then irradiated with UV to form irregularities. This antiglare film had a total light transmittance of 92%, a haze of 45%, and a gloss (angle of 60 °) of 70. As in Example 1, when the surface unevenness shape of this antiglare film was measured and analyzed, the average apex distance Sm was 57 μm, and the ten-point average roughness Rz was 1.29 μm. Furthermore, Table 1 shows the result of calculating the inclination angle distribution of the uneven surface when divided into small areas of 0.3 μm square. FIG. 5 shows a three-dimensional shape profile of the antiglare film. Similarly to Example 1, FIG. 6 and Table 1 show the results of measuring the reflected and scattered light using a goniophotometer. Furthermore, the antiglare film is mounted and the evaluation results are shown in Table 1.

Example 4
The surface of the acrylic thin film (thin film made of polymethyl methacrylate, thickness 10 μm) has a trapezoidal concavo-convex structure with an average diameter of 20 μm and an average inclination angle of the side wall of 15 °, and has a moderate slope undulation overall. As described above, the concavo-convex structure was formed by excimer laser processing. As in Example 1, when the surface unevenness shape of this antiglare film was measured and analyzed, the average apex distance Sm was 26 μm, and the ten-point average roughness Rz was 0.31 μm. Further, Table 1 shows the result of calculating the inclination angle distribution of the uneven surface when divided into 0.5 μm square regions. Similarly to Example 1, FIG. 6 and Table 1 show the results of measuring the reflected and scattered light using a goniophotometer. Furthermore, the antiglare film is mounted and the evaluation results are shown in Table 1.

  As is clear from Table 1, the antiglare films obtained in the examples show high results in all of reflection, whiteness and sharpness. On the other hand, the antiglare film obtained in the comparative example has low whiteness or sharpness.

FIG. 1 is a three-dimensional shape profile of the antiglare film surface obtained in Example 1. FIG. 2 is a laser micrograph (10x objective) of the antiglare film surface obtained in Example 1. FIG. 3 is a graph showing the relationship between the reflection angle and the gain in the antiglare film obtained in Example 1. FIG. 4 is a three-dimensional shape profile of the antiglare film surface obtained in Example 2. FIG. 5 is a three-dimensional shape profile of the antiglare film surface obtained in Comparative Example 2. FIG. 6 is a graph showing the relationship between the reflection angle and the gain in the antiglare films obtained in Examples 2 to 4 and Comparative Examples 1 and 2.

Claims (9)

Has a surface fine concavo-convex structure, and the area ratio of the region S2 is the tilt angle of 2.5 to 7.5 ° relative to the surface, an antiglare film is not more than 20% of the total surface In the angle range from 10 to 17 ° from the normal to the surface, the anti-glare is that the gain of the reflected scattered light with respect to the standard white plate is 0.1 or more and the half-value angle of the gain of the reflected scattered light is 2 to 5 ° Sex membrane .   The antiglare film according to claim 1, wherein the area ratio of the region S1 having an inclination angle with respect to the surface of less than 2.5 ° is 50% or more with respect to the entire surface.   The antiglare film according to claim 1, wherein the area ratio of the region S4 having an inclination angle of 10 ° or more with respect to the surface is 1% or more with respect to the entire surface.   The antiglare film according to claim 1, wherein the average apex distance Sm is 20 to 150 μm.   2. The antiglare film according to claim 1, wherein the ratio Rz / Sm of the ten-point average roughness Rz to the average apex distance Sm is 0.005 to 0.02.   At least one selected from alicyclic olefin resins, vinyl acetate resins, (meth) acrylic resins, styrene resins, polyester resins, polycarbonate resins, polyamide resins, cellulose derivatives, and epoxy (meth) acrylates The antiglare film according to claim 1, which is composed of a transparent resin.   A film having a surface with a fine concavo-convex structure composed of at least one transparent resin selected from a (meth) acrylic resin, a styrene resin, a cellulose derivative, and an epoxy (meth) acrylate, and an inclination angle with respect to the surface However, the anti-glare film | membrane whose area ratio of area | region S2 which is 2.5-7.5 degrees is 18% or less with respect to the whole surface, and whose average top space | interval Sm is 25-130 micrometers.   The method for producing an antiglare film according to claim 1 by phase-separating a plurality of resins.   A display device comprising the antiglare film according to claim 1.