KR20090098767A - Anti-glare film, method for manufacturing the same, and display device using the same - Google Patents

Abstract

An anti-glare film, a method for manufacturing the same, and a display device using the same are provided to achieve the anti-glare nature by forming the antiglare film having the specific gain of the reflected light. An antiglare film comprises a plurality of spreading factors formed in a surface. A plurality of protrusions is formed in a surface(14) of an antiglare film(1) as the diffused light member. The surface aggregate formed in the surface of antiglare film has the minute concavo-convex, the antiglare film has the specific diffusion reflection property. The antiglare film is formed in order to achieve the anti-glare property of being excellent. The antiglare film has the function of suppressing the expression of the white turbidity. The antiglare film satisfies I(alpha+1)/I(alpha) ratio more than 0.1-0.6. The I(alpha) is the intensity of the reflected light for the arbitrary angle less than 10° of the right reflection direction of the light which is incident from the normal of the surface to the side of the angle of 5°-30°. The I(alpha+1) is the intensity of the reflected light deviating from by the wide angular orientation as 1° from each angle(alpha).

Description

Anti-glare film, method for manufacturing same, and display device using the same {ANTI-GLARE FILM, METHOD FOR MANUFACTURING THE SAME, AND DISPLAY DEVICE USING THE SAME}

The present invention relates to an anti-glare film, a method for producing the anti-glare film, and a display device using the anti-glare film. In particular, the present invention relates to an anti-glare film used for the surface of a display device such as a liquid crystal display, a plasma display, an electroluminescent display or a cathode ray tube (CRT) display, a method for manufacturing the anti-glare film, and the anti-glare film It relates to the display device used.

In display devices such as liquid crystal displays, plasma displays, CRT displays, and the like, visibility is significantly lowered when ambient light from fluorescent light or the like is reflected on the surface of the display. Thus, the method of forming an optical multilayer film or a low refractive index film on the surface of the display device so that the reflectivity of the surface is reduced, or the anti-glare having a fine uneven surface on the surface of the display device so that the reflected image is blurred by the ambient light scattered and reflected. The method by which the film is formed has been used.

However, when the optical multilayer film is used, the production cost is increased and satisfactory antifouling characteristics cannot be obtained. When the production cost is increased by using a low refractive index film, the final surface has a relatively high reflectance, causing a problem of reflection causing annoyance to the surface. On the other hand, it includes a mixture of a silica filter, an organic filter, and the like to form a surface having a fine concavo-convex, by using a diffuse reflection method to blur the surface reflection of the display, it is possible to obtain anti-glare characteristics. However, especially when the ambient light is strong, and the contrast is reduced, the expression of turbidity is strong, and the visibility is lowered.

Recently, with the desire to suppress the expression of turbidity, surface treatments that suppress the expression of turbidity and increase contrast have been developed and some methods of such surface treatments. For example, Unexamined Japanese Patent Application Publication No. 2002-365410 (hereinafter referred to as "Patent Document 1") discloses a method for obtaining a non-glare anti-glare film while suppressing reflection on the surface, where the glare The ratio of the intensity of reflected light 20 ° away from the specular reflection direction to the specular reflection intensity of incident light in the direction of −10 ° from the normal to the surface of the prevention film is less than 0.2, half of the peak of the reflected light intensity The band width is over 7 °.

In Japanese Unexamined Patent Application Publication No. 2004-61853 (hereinafter referred to as "Patent Document 2"), the specular reflection of incident light collimated at an angle of 5 ° from the normal to the surface of the anti-glare film is determined from the specular reflection. An anti-glare film is disclosed that is substantially parallel to the reflectivity toward the specular reflection direction of incident light at an angle of 0.2 ° away. In addition, the patent document 2 is obtained by standardizing the reflected light intensity toward the normal direction with incident light of 20 ° or more to the anti-glare film using a standard scattering plate by the same measurement method (the value is 1 / 1,000 or less). And a method for obtaining an anti-glare film having the following) (hereinafter, the reflected light intensity normalized using the intensity of the light reflected from the standard diffuser plate is referred to as "gain").

Japanese Unexamined Patent Application Publication Nos. 2006-53371 and 2004-240411 (hereinafter referred to as "Patent Document 3" and "Patent Document 4") have described a method for obtaining an anti-glare film, where a conventional The reflectivity is 1% or less for the incident light of 5 ° to 30 ° to the anti-glare film, and the ratio of the reflectivity toward 30 ° or more with respect to the specular reflection direction with respect to the specular reflection is 0.001 or less.

However, there is a trade off between anti-glare properties and suppression of turbidity expression, making it difficult to design anti-glare films having all of these properties, and the solution is not sufficiently good. For example, a known anti-glare film having an uneven surface formed by using a silica filler satisfies the diffuse reflection characteristic specified in Patent Document 1, and has a strong haze even when the intensity ratio is 0.1 or less, and the anti-glare film is half Anti-glare characteristics can be achieved at a band width of 7 ° or less.

The diffuse reflection characteristic described in Patent Document 2, in which the specular reflectance is the same as the reflectance toward the specular reflection direction of the incident light deviated by 0.2 ° from the specular reflection, is satisfied by the film having a surface state close to specular reflection, and described in Patent Document 2 Technology alone is difficult to achieve anti-glare properties. On the other hand, from the studies conducted by the inventors, when the gain in the normal direction is about 1/100, the expression of the turbidity of the film decreases satisfactorily, but the glare so that the gain in the actual normal direction is 1 / 1,000 or less. It has been found that it is difficult to prepare the prevention film.

Regarding the diffuse reflection characteristics specified in Patent Documents 3 and 4, it has been found that the anti-glare film sometimes has a specular reflectance of 1% or less even though the anti-glare film has a relatively uniform surface and a large reflectance. In addition, it was found that, as an example, the anti-glare film subjected to the low reflection treatment with the low refractive index layer formed on the surface satisfies the above diffuse reflection property, but the anti-glare property is not sufficiently good.

In addition, as described above, the anti-glare film having a fine concavo-convex shape on the surface provides an anti-glare property, but there is a problem that the film has a rough appearance in visual intuition. When an anti-glare film having a large rough appearance is used for the display device, the visibility of the image is lowered.

Therefore, it is desirable to provide an anti-glare film having the advantage of suppressing the appearance of turbidity while achieving anti-glare characteristics, and having the advantage of reduced rough appearance, a manufacturing method thereof, and a display device employing the same.

According to a first aspect of the present invention, there is provided an anti-glare film having a plurality of diffusion elements formed on a surface, wherein the anti-glare film has (1) I (α) of 5 ° to 30 ° from the normal direction of the surface. (2) I (α + 1) is the intensity of the reflected light reflected at an angle of 10 ° or less from the specular reflection direction of the incident light on the surface having a plurality of diffusing elements thereon at an angle of (2) Deviated by 1 ° in the wide-angle direction (addition of 1 ° to any angle α), the I (α + 1) / I (α) ratio greater than 0.1 to 0.6, and the gain are the standard diffusion when the intensity of reflected light is When obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the plate, the gain of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light has an optical characteristic of 0.02 or less. The diffusion element has an average spacing of 50 to 300 micrometers.

According to a second aspect of the present invention, there is provided an anti-glare film having a plurality of diffusion elements on a surface, wherein the anti-glare film comprises (1) a plurality of diffusions at an angle of 5 ° to 30 ° from the normal direction of the surface. For incident light on the surface with the element, it has a full width of 6.0 ° to 28.0 ° at a 1/100 reflected light intensity relative to the peak of the reflected light intensity, and (2) the gain is reflected light intensity using the specularly reflected light intensity of the standard diffuser plate. When obtained by normalizing to 1, it has an optical characteristic having a gain of 0.02 or less of light reflected in a direction of 20 ° or more from the normal reflection direction of incident light. The diffusion element has an average spacing of 50 to 300 micrometers.

According to a third aspect of the present invention, there is provided an anti-glare film having a plurality of diffusion elements on a surface, wherein the anti-glare film comprises (1) a plurality of diffusions at an angle of 5 ° to 30 ° from the normal direction of the surface. For incident light on a surface with elements, it has a full width of 10.0 ° to 45.0 ° angle at 1 / 1,000 reflected light intensity with respect to the peak of reflected light intensity, and (2) the gain is reflected light intensity using the specular light intensity of the standard diffuser plate. When obtained by normalizing to 1, it has an optical characteristic having a gain of 0.02 or less of light reflected in a direction of 20 ° or more from the normal reflection direction of incident light. The diffusion element has an average spacing of 50 to 300 micrometers.

According to the fourth aspect of the present invention, fine irregularities are formed on the surface of the anti-glare film by a shape transfer method, sand blast method, laser beam machining method, wet etching method or Bernard cell formation method so that a plurality of diffusion elements are formed on the surface. There is provided a method for producing an anti-glare film comprising forming a. The anti-glare film has (1) any angle α or less from 10 ° from the normal reflection direction of incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface. Is the intensity of the reflected light reflected by (), and when I (α + 1) is the intensity of the reflected light shifted by 1 ° in the wide-angle direction from the arbitrary angle α (addition of 1 ° to any angle α). 20 from the normal reflection direction of the incident light when the ratio has an I (α + 1) / I (α) ratio greater than 0.6 and (2) gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the standard diffuser plate. The gain of light reflected in a direction of at least ° has an optical characteristic of 0.02 or less, and the diffusing element has an average spacing of 50 to 300 micrometers.

According to the fifth aspect of the present invention, fine irregularities are formed on the surface of the anti-glare film by a shape transfer method, sand blast method, laser beam machining method, wet etching method or Bernard cell formation method so that a plurality of diffusion elements are formed on the surface. There is provided a method of manufacturing an anti-glare film comprising forming a. The anti-glare film has (1) 6.0 ° to 1/100 reflection light intensity with respect to the peak of the reflected light intensity with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface. It has a full width of 28.0 ° angle, and (2) 0.02 or less of the light reflected in the direction of 20 ° or more from the normal reflection direction of the incident light when the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the standard diffuser plate. With gain, it has optical properties, and the diffusing element has an average spacing of 50 to 300 micrometers.

According to the sixth aspect of the present invention, fine irregularities are formed on the surface of the anti-glare film by a shape transfer method, sand blast method, laser beam machining method, wet etching method or Bernard cell formation method so that a plurality of diffusion elements are formed on the surface. There is provided a method of manufacturing an anti-glare film comprising forming a. The anti-glare film has (1) 10.0 ° at 1 / 1,000 reflected light intensity with respect to the peak of reflected light intensity with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface. It has a full width of 45.0 ° angle and (2) 0.02 or less of the light reflected in the direction of 20 ° or more from the normal reflection direction of the incident light when the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the standard diffuser plate. With gain, it has optical properties, and the diffusing element has an average spacing of 50 to 300 micrometers.

According to the seventh aspect of the present invention, there is provided a display device including a display portion for displaying an image and an anti-glare film formed on the display side of the display portion. The anti-glare film has a plurality of diffusing elements on the surface, and (1) I (α) is formed in response to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface. 1 is the intensity of reflected light reflected at an arbitrary angle α of 10 ° or less from the specular reflection direction, and I (α + 1) is shifted by 1 ° in the wide-angle direction from the arbitrary angle α (arbitrary angle α 1)] has an I (α + 1) / I (α) ratio of greater than 0.1 to 0.6 when the intensity of the reflected light, and (2) the gain to the reflected light intensity of 1 using the specular intensity of the standard diffuser plate. When obtained by normalization, the gain of light reflected in a direction of 20 ° or more from the direction of normal reflection of incident light has an optical characteristic of 0.02 or less. The diffusion element has an average spacing of 50 to 300 micrometers.

According to the eighth aspect of the present invention, there is provided a display device including a display portion for displaying an image and an anti-glare film formed on the display side of the display portion. The anti-glare film has a plurality of diffusion elements on the surface, and (1) with respect to the incident light on the surface having a plurality of diffusion elements at an angle of 5 ° to 30 ° from the normal direction of the surface, to the peak of the reflected light intensity It has a full width of 6.0 ° to 28.0 ° angle at 1/100 reflected light intensity, and (2) 20 from the specular reflection direction of incident light when the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the standard diffuser plate. Optical properties, with a gain of 0.02 or less of light reflected in a direction of at least °, wherein the diffusing element has an average spacing of 50 to 300 micrometers.

According to a ninth aspect of the present invention, there is provided a display device including a display portion for displaying an image and an anti-glare film formed on the display side of the display portion. The anti-glare film has a plurality of diffusion elements on the surface, and (1) with respect to the incident light on the surface having a plurality of diffusion elements at an angle of 5 ° to 30 ° from the normal direction of the surface, to the peak of the reflected light intensity Having a full width of 10.0 ° to 45.0 ° angle at 1 / 1,000 reflected light intensity, and (2) when gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the standard diffuser plate, 20 from the specular reflection direction of the incident light. It has optical properties, with a gain of 0.02 or less of light reflected in a direction of at least °, wherein the diffusing element has an average spacing of 50 to 300 micrometers.

In each of the first, fourth and seventh aspects of the present invention, any angle of 10 ° or less with respect to the intensity of reflected light shifted by 1 ° in a wide angle direction from any angle (addition of 1 ° to an arbitrary angle α) An anti-glare film having a specific ratio of intensity of reflected light toward an angle can achieve anti-glare characteristics. In particular, with respect to the direction of specular reflection of incident light on a surface having a plurality of diffusing elements thereon at an angle of 5 ° to 30 ° with respect to the normal of the surface, I (α) is an angle of 10 ° or less from the specular reflection direction ( is the intensity of the reflected light reflected at α, and I (α + 1) is the intensity of the reflected light shifted by 1 ° from the arbitrary angle α in the wide angle direction (addition of 1 ° to any angle α). The I (α + 1) / I (α) ratio is greater than 0.1 to 0.6. When the I (α + 1) / I (α) ratio to the reflected light intensity is greater than 0.1, anti-glare characteristics can be achieved, and when the I (α + 1) / I (α) ratio is 0.6 or less, the appearance of turbidity This can be suppressed.

In each of the second, fifth and eighth aspects of the present invention, an anti-glare film having a specific full width of the angle at the 1/100 reflected light intensity with respect to the peak of the reflected light intensity can achieve the glare characteristic. In particular, for incident light on a surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface, the full width of the angle at 1/100 reflected light intensity with respect to the peak of the reflected light intensity is 6.0 ° to 28.0 °. . When the full width of the angle at 1/100 reflected light intensity with respect to the peak of the reflected light intensity is 6.0 DEG or more, anti-glare property can be achieved, and when the full width of the angle is 28.0 DEG or less, the expression of turbidity can be suppressed. .

In each of the third, sixth, and ninth aspects of the present invention, an anti-glare film having a specific full width of an angle at 1 / 1,000 reflected light intensity with respect to a peak of reflected light intensity may achieve anti-glare characteristics. In particular, for incident light on a surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° with respect to the normal direction of the surface, the full width of the angle at 1 / 1,000 reflected light intensity with respect to the peak of the reflected light intensity is 10.0 ° to 45.0 ° to be. When the full width of the angle at 1 / 1,000 reflected light intensity with respect to the peak of the reflected light intensity is 10.0 ° or more, anti-glare property can be achieved, and when the full width of the angle is 45.0 ° or less, the expression of turbidity can be suppressed. .

In each of the first to ninth aspects of the present invention, the expression of turbidity can be suppressed when the anti-glare film has a specific gain of light reflected in the 20 ° direction from the specular reflection direction. In particular, the gain of the light reflected in the direction of 20 degrees or more from the specular reflection direction is 0.02 or less.

When the antiglare film has a particular average spacing between the diffusing elements, the rough appearance may be reduced. In particular, the average spacing between the diffusing elements is between 50 and 300 micrometers.

According to the present invention, it is possible to provide an anti-glare film having an anti-glare property while suppressing the expression of turbidity and having a reduced roughening advantage, a manufacturing method thereof, and a display device employing the same.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In all the drawings of the following embodiments, the same parts or parts represent the same reference numerals.

The present invention claims priority to Japanese Patent Application No. 2007-033855 filed with the Japan Patent Office on February 14, 2007 and Japanese Patent Application No. 2007-341220 filed with the Japan Patent Office on December 28, 2007, the contents of which Included herein.

(1) First embodiment

(1-1) Composition of the anti-glare film

1 is an enlarged cross-sectional view showing an example of the configuration of an anti-glare film according to a first embodiment of the present invention. A plurality of protrusions are formed on the surface 14 of the anti-glare film 1 as a light scattering member, so that the surface aggregate has fine irregularities. The present inventors conducted a high intensity and intensive study on the diffusion characteristics of the anti-glare film (1). As a result, it was found that the anti-glare film 1 having the specific diffuse reflection characteristic described below can achieve excellent anti-glare characteristics and suppress the expression of turbidity, and succeeded in obtaining the anti-glare film.

In order to achieve the anti-glare property, the absolute value of the specular reflection intensity should be reduced, but it is more preferable that the diffuse reflection characteristic is not changed rapidly. There is a correlation between the visible sensitivity of humans and the logarithm of the light intensity, so that when the log of intensity for the diffuse reflection characteristic changes drastically, the reflective edge of the light source is visually recognized so that the surface has anti-glare characteristics. Will not have Thus, the anti-glare film 1 according to the first embodiment satisfies the I (α + 1) / I (α) ratio of 0.1 to 0.6 or more, where I (α) is 5 from the normal of the surface 14. Is the intensity of reflected light towards any angle of 10 ° or less in the direction of specular reflection of light incident on the plane of an angle of 30 °, and I (α + 1) deviates from the angle α by 1 ° in a wide angle direction The intensity of the reflected light. If the I (α + 1) / I (α) ratio is not less than 0.1, the intensity may change rapidly and the edge may be observed, so that the anti-glare characteristic cannot be recognized. If the I (α + 1) / I (α) ratio is greater than 0.6, the expression of turbidity becomes large even if the anti-glare characteristic is obtained.

With respect to light incident in each direction of 5 ° to 30 ° from the normal direction of the surface 14, the full width of the angle at which the reflected light intensity is 1/100 to the peak of the reflected light intensity is 6.0 ° to 28.0 °. Then, anti-glare characteristics similar to the diffuse reflection characteristics defined by the above description are obtained. If the full width of the angle does not exceed 6.0 °, the intensity changes rapidly and the edge can be observed. If the full width of the angle exceeds 28.0, the appearance of turbidity may appear even if the anti-glare property is obtained.

Similarly, with respect to light incident in the direction of 5 ° to 30 ° with respect to the normal direction of the surface 14, the full width of the angle that becomes the reflected light intensity of 1 / 1,000 to the peak of the reflected light intensity is 10.0 °. ˜45.0 °, an anti-glare characteristic similar to the diffuse reflection characteristic specified as described above is obtained. If the full width of the angle is less than 10.0 °, the strength is drastically changed so that the edge is observed. If the full width of the angle is larger than 45.0 °, the appearance of turbidity appears even if the anti-glare property is obtained.

The diffuse reflection characteristic of the anti-glare film 1 is determined by measuring the reflected light intensity using, for example, a goniophotometer GP-1-3D manufactured and sold by OPTEC Co., Ltd. In the above measurement, in order to eliminate the effect of reflection on the black surface such that the diffuse reflection characteristic of the anti-glare film 1 or the like is determined, black glass or a black acrylic sheet is made to pass through the surface of the anti-glare film 1 through the adhesive ( 14) can be joined oppositely.

On the other hand, with respect to the appearance of turbidity, reflection of an angle of 10 degrees or more from the forward direction is important. The reason for this is that the degree of turbidity is reduced by reducing the light component diffused in the wide angle direction of the specular reflection direction. Accordingly, the gain of light reflected in the direction of 20 ° or more from the specular reflection direction of the specular reflection direction of the incident light from which the gain is obtained by normalizing the reflected light intensity using the specular reflection intensity of the standard diffusion plate such as "1" is obtained from the surface 14. The anti-glare film 1 according to the first embodiment of the present invention satisfies the diffuse reflection characteristic so as to be 0.02 or less with respect to incident light on the surface in the direction of an angle of 5 ° to 30 ° from the normal line of. The gain of the light reflected toward the direction of 20 ° or from the specular reflection direction is 0.01 or less. The gain of the light reflected toward the direction of 10 degrees or more may be 0.25 or less, preferably 0.08 or less. Thus, the expression of turbidity of the anti-glare film can be suppressed. Gain refers to reflected light intensity normalized using a standard diffuser plate, and gain is normalized using the same reflected light intensity as measured using a barium sulfate standard diffuser plate, such as reference numeral "1". Is the value of the reflected light intensity.

It is preferable that the anti-glare film 1 has a surface haze of 5.0% or less, more preferably 3.0% or less. When the surface blurring degree is 5.0% or less, the anti-glare film has reduced expression of white turbidity, and when the surface blurring degree is 3.0% or less, the anti-glare film has further reduced expression of whiteness. The surface haze is a value obtained by detecting surface dispersion, and the higher the surface haze, the higher the appearance of turbidity. On the other hand, there is no particular limitation as to the degree of internal blurring.

The internal blur as used herein adheres to the surface of the anti-glare layer 12 under the conditions for the measurement method described in JIS K7136, for example, using a blur meter HM-150 (manufactured by MURAKAMI COLOR RESEARCH LABORATORY). It is determined by the measuring method regarding the anti-glare film 1 which has an adhesive agent with a cloudiness of 1.0% or less. The surface blurring degree is determined by the measuring method for the anti-glare film 1 in the same manner as the determination of the internal blurring degree, thereby obtaining a difference between the final value and the internal blurring degree.

The optical characteristics of the anti-glare film 1 are obtained by the diffusion element formed on the surface such that the surface 14 has fine unevenness. By reducing the size of the diffusing element, scintillation caused by a rough surface shape on visual perception or flashing of the screen (hereafter referred to as flashing of the screen is often referred to as “surface flashing”) can be suppressed.

The meaning of the rough face shape of visual perception is that by means of reflection from the light scattering member in different directions when the perceived particle size having non-uniform brightness reflects the light source having uniform light intensity from the anti-glare film 1. It is observed. Therefore, it is advantageous for the space between the light scattering members to be reduced so that the individual light scattering members can be spaced apart from each other when observed with the optimum viewing distance of the image display apparatus using the anti-glare film 1. Specifically, the average peak valley between the light scattering members is reduced when the light scattering member is specified by volume diffusion, or when the light scattering member is specified by the surface scattering. By reducing the distance Sm, the rough surface shape can be suppressed.

Therefore, in the anti-glare film 1 according to the first embodiment of the present invention, the average space between the light scattering members, that is, the average peak valley spacing Sm of the surface 14 is 300 μm or less, more preferably It satisfies the characteristic of being 220 micrometers or less. The average space between the light scattering members, that is, the average peak valley spacing Sm of the surface 14 of the anti-glare film 1 is preferably 2 µm or more in view of appropriately controlling the scattering reflection characteristics and preventing coloring. 50 micrometers or more are preferable from a viewpoint of the control characteristic.

For an object placed at a distance D (cm) from the inspector, the resolution d (dpi) of the inspector with a visual acuity (V) that distinguishes white from black is determined by the equation:

d = 2.54 x 3,438 x V / D

From the calculations, it was found that the resolution of an inspector with a visual acuity of 1.0 at a viewing distance of 100 cm was about 290 μm. Therefore, when the average peak valley spacing Sm is within this range, the rough surface shape can be suppressed.

As a roughness parameter from the roughness curve obtained by measuring the surface roughness according to the method described in JIS B0601-1994 using, for example, SURFCORDER ET4000A manufactured and sold by Kosaka Laboratory Ltd as an Automatic Microfigure Measuring Instrument. The average peak valley spacing Sm of the anti-glare film 1 is determined.

On the other hand, the surface glare is influenced by the pixel pitch and the relationship between the spaces between the light scattering members of the anti-glare film 1, thus controlling the space according to the pixel pitch of the image display apparatus used. It is desirable to. When the space between the light scattering members is not smaller than the pixel pitch, the relative positional relationship between the individual light scattering members is not uniform, so that it is recognized as surface glare. Thus, surface glare can be prevented when the space between the light scattering members is 1/3 or less, more preferably 1/4 or less, of the pixel size of the image display apparatus.

In 1st Embodiment, the anti-glare film 1 which has fine unevenness | corrugation on the surface of the anti-glare film 1 is resin, for example. Resins used in the anti-glare film 1 include, for example, at least one or more ionizing radiation curable resins cured by ultraviolet radiation or electron radiation, thermosetting resins cured by heating, or thermoplastic resins in terms of easy production. do. As the ion radiation curable resin, an acrylate resin such as urethane acrylate, epoxy acrylate, polyester acrylate, polyol acrylate, polyether acrylate, or melamine acrylate can be used. Regarding the properties of the cured resin, in particular, a resin which produces a cured resin having excellent light transmittance in terms of achieving image transmittance, or a hardening having high strength in terms of obtaining flaw resistance Preferred are resins for producing the resins and resins which can be appropriately selected. The ion radiation curable resin is not limited to an ultraviolet curable resin, and any ion radiation curable resin can be used as long as it has light transmittance, but ion emission in which the color of the transmitted light or the amount of transmitted light does not change significantly due to coloration or blurring Curable resin is preferable.

The photosensitive resin is obtained by incorporating a photopolymerization initiator into an organic material capable of forming a resin such as a monomer, oligomer or polymer. For example, an isocyanate monomer or prepolymer is reacted with a polyester polyol, and a methacrylate monomer or acrylate having a hydroxyl group is reacted with the final product to obtain a urethane acrylate resin.

As the photopolymerization initiator, for example, benzophenone derivatives, acetophenone derivatives, anthraquinone derivatives and the like can be used individually or in combination. In the photosensitive resin, a component for facilitating film formation such as an acryl resin may be appropriately selected and included.

In the photosensitive resin, a light stabilizer, an ultraviolet light absorber, an antistatic agent, a flame retardant, an antioxidant, and the like may be added in an appropriate amount as desired. Silica fine particles and the like can be added as a viscosity modifier.

(1-2) Method for manufacturing anti-glare film

With reference to FIGS. 2A-2E, the method for manufacturing the anti-glare film 1 which concerns on 1st Embodiment is demonstrated.

(Process for preparing the mother die)

First, prepare the base material to be processed. Examples of the shape of the base material include a substrate shape, a sheet shape, a film shape, and a block shape. Examples of the material for the base material include plastic, metal, and glass. Next, in order to pattern the surface of the base material fine irregularities along the surface 14 of the anti-glare film 1, the base material is, for example, a mask imaging method, a pressing method, a molding using a KrF excimer laser. Mother mold 21 having a fine concavo-convex shape processed by a method using a stamper, a cutting method, a sand blasting method, a wet etching method, and the like inverted on the surface 14 as shown in FIG. 2A. ) In order for the anti-glare film 1 to achieve the diffuse reflection characteristic as described above, the surface of the mother mold 21 has fine unevenness, and an average peak valley of 300 µm or less, preferably 220 µm or less. It has a spacing Sm.

(Process for preparing a replication master)

Next, a conductive film is formed in the fine uneven part of the mother die 21 obtained by the electroless plating method, for example. The conductive film is a metal film made of a metal such as nickel. Thereafter, the mother mold 21 having the conductive film is placed in the electroforming apparatus, and a metal plating layer such as a nickel plating layer is formed on the conductive film by, for example, an electroplating method. Thereafter, the metal plating layer is separated from the mother mold 21 to obtain a replica master 22 having fine irregular portions inverted in the mother mold 21, as shown in FIG. 2B.

Thereafter, the obtained replica master 22 is subjected to surface treatment, for example, a metal plating layer such as a nickel plating layer is formed on the minute irregularities of the final replica master by the electroplating method. Thereafter, the metal plating layer is separated from the replica master 22 to obtain a replica master 23 having the same fine concavo-convex portion as that of the mother mold 21, as shown in FIG. 2C.

When the mother mold is made of an organic substrate or the like which can be damaged, a child mold and a grandchild mold are prepared from the mother mold as described above and when separated from the mother mold. Even when the mother mold is damaged, a large amount of grand child mold is prepared using the child mold. On the other hand, when the mother mold is not likely to be damaged and the child mold can be repeatedly prepared from the mother mold, the mother mold has the same shape as the shape of the anti-glare layer and the final inverted child mold is transferred ( The mother mold is processed so that it can be used as a transfer mold.

(Process to prepare anti-glare film)

Next, as shown in FIG. 2D, in order to make the thickness of the photosensitive resin uniform, a photosensitive resin such as an ultraviolet curable resin is injected into the fine concavo-convex portion of the obtained replication master 23. The fine concave-convex portion of the surface 14 is obtained by shape transfer, so that it is not necessary to add the fine particles to the photosensitive resin, but to finely control the fine particles in order to finely control the blurring or surface shape. It can be added to the sensitive resin.

Next, the resin is cured by light irradiation such as ultraviolet irradiation from the side of the injected photosensitive resin. Then, as shown in FIG. 2E, the cured photosensitive resin is separated from the replica master 23. Therefore, the anti-glare film which has the fine uneven | corrugated part which is a waveform suitable for the surface 14 is obtained.

The anti-glare film 1 prepared by the above process has a specific diffuse reflection characteristic as described above, thereby suppressing the appearance of turbidity and providing anti-glare characteristics. In addition, the anti-glare film has a specific space between the light scattering members formed on the surface 14, whereby the rough surface shape is reduced. Thus, by using an anti-glare film 1 of a display device such as a liquid crystal display, a plasma display, an electroluminescent display, or a CRT display, it is possible to provide a display having excellent anti-glare characteristics and excellent contrast, and thus visibility Is improved.

(2) 2nd Embodiment

(2-1) structure of anti-glare film

3 is an enlarged cross-sectional view showing an example of the structure of an anti-glare film according to a second embodiment of the present invention. The anti-glare film 1 includes a base 11 and an anti-glare layer 12 having fine particles 13 formed on the base 11. The fine particles 13 form a plurality of ridges on the surface of the antiglare layer 12 as a light scattering member. As a result, the surface of the antiglare layer 12 has fine irregularities as a whole. MEANS TO SOLVE THE PROBLEM This inventor carried out intensive and intense research about the diffuse reflection characteristic of the anti-glare film 1. As a result, it was found that the anti-glare film 1 having the specific diffuse reflection characteristic described below has excellent anti-glare characteristics and can suppress the expression of turbidity, and thus succeeded in obtaining the anti-glare film.

In order to achieve the anti-glare property, the absolute value of the intensity of ordinary reflected light should be reduced, and it is more preferable that the diffuse reflection property is not changed rapidly. Since there is a correlation between the visibility of a person and the log of light intensity, when the log of intensity to diffuse reflection characteristic changes rapidly, the reflective edge of the light source on the surface is visually recognized, so that the surface has anti-glare characteristics. There will be no. Therefore, as shown in FIG. 4, with respect to incident light on the surface of the antiglare layer 12 in the direction 3 of 5 ° to 30 ° from the normal line 2 to the surface, I (α + 1) / So that the ratio of I (α) is greater than 0.1, where I (α) is the intensity of reflected light in the direction 5 in any angle α less than 10 ° from the spherical direction 4, α + 1) is the intensity of reflected light in the direction 6 extended by 1 °), the anti-glare film 1 according to the second embodiment of the present invention satisfies the diffuse reflection characteristic. In such a case, the change of the log of the reflected light intensity may be -1 or less, so that the edge of the reflection becomes unclear, thereby obtaining anti-glare characteristics. On the other hand, when the ratio of I (α + 1) / I (α) to the reflected light intensity is increased, the anti-glare property can be obtained, but the expression of turbidity becomes stronger. Therefore, the ratio of I (α + 1) / I (α) to the reflected light intensity is 0.6 or less.

FIG. 5 is a graph showing an example of the ratio between the angle α and the reflected light intensity I (α) when the spherical direction is 0 ° with respect to the incident light on the surface of the antiglare layer 12. The arrows in FIG. 5 represent the full width of the angle at 1/100 reflected light intensity with respect to the peak of reflected light intensity. In the incident light on the surface of the antiglare layer 12 in the direction 3 at an angle of 5 to 30 ° from the surface normal 2, the inventors have shown that at the 1/100 reflected light intensity with respect to the peak of the reflected light intensity. It has been found that antiglare properties similar to the specific diffuse reflection property can be achieved when the full width of the angle of is from 6.0 ° to 28.0 °. When the full width of this angle is less than 6.0 degrees, the change in intensity is sharp, so that the edge of the reflection can be observed. On the other hand, when the full width of the angle is larger than 28.0 °, anti-glare characteristics are obtained, but the appearance of turbidity appears.

Similarly, in incident light onto the surface of the antiglare layer 12 in the direction 3 at an angle of 5 ° to 30 ° from the surface normal 2, 1 / 1,000 reflected light intensity for a peak of reflected light intensity. When the full width of the angle at is 10.0 ° to 45.0 °, anti-glare characteristics similar to the specific diffuse reflection characteristics can be obtained. The full width of the angle at the 1/10 reflected light intensity with respect to the peak may likewise be specified, but the diffuse reflective property of the surface that is glossy so that reflection can be observed and that has adequate anti-glare properties is an angle of about 1/10 intensity It has been found that is similar to each other in that it is not possible to obtain the anti-glare property only by specifying the diffuse reflection property.

The diffuse reflection characteristic of the anti-glare film 1 is determined by measuring the reflected steel intensity using, for example, a Gioniophotometer GP-1-3D manufactured and sold by OPTEC Co., Ltd. In the above measurement, an adhesive is applied to the surface of the anti-glare film 1 in which the anti-glare layer 12 is not formed so as to remove the reflection effect from the black surface such that the diffuse reflection characteristic of the anti-glare film 1 or the like is determined. The black glass or the black acrylic plate is bonded together.

On the other hand, for the expression of turbidity, reflection at an angle of 10 degrees or more from the specular reflection direction is very important. This is because the turbidity can be lowered by reducing the light component diffused at an angle larger than the angle in the specular reflection direction from the normal of the surface. Therefore, in the anti-glare film 1 according to the first embodiment of the present invention, the incident light on the surface of the anti-glare layer 12 in the direction 3 at an angle of 5 ° to 30 ° from the normal 2 of the surface On the other hand, when normalized using the intensity of specularly reflected light from the standard diffuser plate as indicated by reference numeral 1, the gain of light reflected at 20 ° or more from the specular reflection direction is 0.02 or less, more preferably 0.01 or less, and 10 from the specular reflection direction. The gain of the light reflected in the direction of ° or more is 0.25 or less, more preferably 0.08 or less diffuse reflection characteristic is satisfied. In this case, the expression of the turbidity of the anti-glare film is suppressed. As used herein, “gain” means the intensity of reflected light normalized using a standard diffuser plate, and in an embodiment of the invention, the gain refers to the intensity of normal reflected light measured using a barium sulphate standard diffuser plate at the same measurement. It is the value of the reflected light normalized using.

The anti-glare film 1 preferably has a surface haze of 5.0% or less, more preferably 3.0% or less. If the surface haze is 5.0% or less, the appearance of the anti-glare film is reduced in turbidity, and if the surface haze is 3.0% or less, the anti-glare film is more reduced in the expression of turbidity. Surface haze is a value obtained by detecting surface dissipation, and the appearance of turbidity increases as surface haze increases. On the other hand, there is no restriction | limiting in particular about internal haze, It determines with the microparticles | fine-particles 13 contained in the anti-glare layer 12 etc.

In an embodiment of the present invention, the internal haze is the state of the measurement method disclosed in JIS K7136 using, for example, a haze meter HM-150 (manufactured and sold by MURAKAMI COLOR RESEARCH LABORATORY). It is determined by measuring the anti-glare film 1 with an adhesive having a haze of 1.0% or less bonded on the surface of the anti-glare layer 12 below. Surface haze is determined by measuring on the anti-glare film 1 in the same manner as the determination of the internal haze, and a difference between the resultant value and the internal haze is obtained.

This optical characteristic of the anti-glare film 1 is obtained by the diffusion element formed on the surface of the anti-glare layer 12 such that the surface of the anti-glare layer 12 has fine uneven portions. By reducing the size of the diffusing element, the glare caused by the rough appearance of the surface or the glare of the screen (hereinafter, the reflection of the screen is often referred to as "surface glare") can be suppressed.

The rough appearance of the surface means non-uniform brightness from the surface caused by reflection in one diffusing element in different directions when a light source having a uniform light intensity is reflected in the anti-glare film 1. Therefore, it is advantageous to reduce the distance between the diffusion elements so that the individual diffusion elements can be separated from each other when the image display device is observed at the optimum viewing distance using the anti-glare film 1. In particular, the rough appearance reduces the average spacing between the diffusing elements when the diffusing elements are characterized by volume diffusion, or reduces the average peak-valley spacing Sm when the diffusing elements are characterized by surface diffusion. Can be suppressed by

Therefore, in the anti-glare film 1 according to the second embodiment of the present invention, the average spacing between the diffusion elements, that is, the average peak valley spacing Sm of the surface of the anti-glare layer 12 is 300 μm or less, more preferably. Satisfies the specificity of 220 µm or less. The average spacing between the diffusing elements, i.e., the average valley-to-spacing spacing Sm of the surface of the antiglare layer 12, is preferably at least 2 [mu] m in view of rough control of the diffuse reflection properties and prevention of coloration. Preferably, it is 50 micrometers or more from a viewpoint of practical control characteristics.

The resolution d (dpi) of a person having visual acuity in which the person can distinguish black and white with respect to an object located at a distance D (cm) from the person is determined by the following equation.

d = 2.54 × 3,438 × V / D

From this calculation, it is known that the resolution of a person having a vision of 1.0 at a viewing distance of 100 centimeters (cm) is about 290 micrometers (μm). Therefore, the rough appearance can be reduced when the average hill-gol spacing Sm is within the above-mentioned range.

The average hill-bone spacing Sm of the anti-glare film 1 is, for example, a surfcoder manufactured and sold by Kosaka Laboratory Ltd. as an Automatic Microfigure Measuring Instrument. (SURFCORDER) can be determined by the roughness parameter obtained by measuring the surface roughness according to the method disclosed in JIS B0601-1994 using ET4000A.

On the other hand, the surface glare is influenced by the relationship between the spacing between the diffusing elements of the anti-glare film 1 and the pixel pitch, and therefore it is preferable to control the spacing in accordance with the pixel pitch of the image display apparatus used. When the spacing between the diffusing elements is not smaller than the pixel pitch, the relative positional relationship is not uniform among the individual diffusing elements, so it is recognized as surface glare. Thus, surface glare can be prevented when the spacing between the diffusing elements is 1/3 or less, more preferably 1/4 or less, of the pixel size of the image display apparatus.

The anti-glare film 12 according to the second embodiment of the present invention having the fine concavo-convex portion of the surface includes a resin including, for example, the fine particles 13. At the minute uneven portion of the surface, it is preferable to cover the fine particles 13 with a resin such as an ionizing radiation curable resin. The uneven portion may have a gently inclined uneven portion, for example, it is preferable that the plurality of fine particles 13 are appropriately aggregated in the in-plane direction so as to form one diffusion element. The entire surface of the aggregated fine particles 13 may be covered with a resin such as an ionizing radiation curable resin or a thermosetting resin, or the surface of the fine particles 13 may be exposed as long as the above-described diffuse reflection characteristics are satisfied. However, when the microparticles | fine-particles 13 protrude from the anti-glare layer 12 so that a steep inclination part may be formed, it will be hard to satisfy the diffuse reflection characteristic mentioned above, and a surface will have a rough appearance externally. Thus, when the surface of the microparticles 13 is exposed, it is preferable that only a part of the surface of the microparticles 13 is located at the tip 7 of the protrusion, for example as a diffusion element.

As used herein, the term "a plurality of fine particles 13 are properly agglomerated in the in-plane direction" means that (1) all the fine particles 13 are not laminated to each other in the thickness direction of the anti-glare layer 12 in the in-plane direction. Only aggregated, or (2) almost all fine particles 13 are aggregated in the in-plane direction, and the remaining fine particles 13 are laminated with each other in the thickness direction so that the degree of turbidity does not increase (using a black glass sheet) Up to 2.0). All particulates 13 ideally form two-dimensional aggregates, but some of the particulates 13 can be separated from one another without forming aggregates such that the turbidity does not increase.

As a resin used for the antiglare layer 12 from the viewpoint of ease of manufacture, for example, an ionizing radiation curable resin curable by irradiation of ultraviolet light or an electron beam or a thermosetting resin curable by heat is preferable, and irradiation of ultraviolet light is preferable. The photosensitive resin which can harden | cure by is most preferable. As the photosensitive resin, an acrylate resin such as urethane acrylate, epoxy acrylate, polyester acrylate, polyol acrylate, polyether acrylate or melamine acrylate can be used. As a property of the cured resin, a resin which can produce a cured resin having the best transmittance to light in terms of achieving image transmittance is particularly preferable or a cured having a high hardness in terms of obtaining resistance to scratches. Particular preference is given to resins capable of producing a modified resin, and the resins may be appropriately selected. The ionizing radiation curable resin is not limited to an ultraviolet curable resin, and any ionizing radiation curable resin can be used as long as it has a transparency to light, but there is no ionization without a significant change in the color tone or amount of transmitted light by color or haze. Radiation curable resins are preferred.

Photosensitive resins are obtained by including a photopolymerization initiator in an organic material capable of forming a resin such as a monomer, oligomer or polymer. For example, urethane acrylate resins are obtained by reacting an isocyanate monomer or polyester polyol with a prepolymer and reacting a acrylate monomer having a reactive acrylate or hydroxyl group with the final product.

As the photopolymerization initiator, for example, benzophenone derivatives, acetophenone derivatives, anthraquinone derivatives and the like can be used individually or in combination. In the photosensitive resin, a component for facilitating film formation such as an acrylic resin can be appropriately selected and mixed.

In the photosensitive resin, a light stabilizer, an ultraviolet light absorber, an antistatic agent, a flame retardant, an antioxidant, or the like may be appropriately added if desired. Silica fine particles and the like may be added as the viscosity modifier.

As the fine particles 13, for example, organic fine particles or inorganic fine particles are used. As the organic fine particles, beads such as acrylic, styrene, acrylic-styrene copolymers, melamine or polycarbonate beads can be used. It may be crosslinked or noncrosslinked, and any spherical or flattened particulate composed of plastic may be used. As the fine particles 13, for example, those having an average particle diameter of 5 nanometers (nm) to 15 micrometers (µm) are used. If the average particle diameter of the fine particles exceeds 15 mu m, the light reflected from the surface adversely causes glare. On the other hand, when the average particle diameter is less than 5 nm, the particles dissipated during preparation of the paint are disadvantageously reaggregated. The average particle diameter of the fine particles 13 can be measured by, for example, laser diffraction.

Although not shown, the anti-glare film 1 may include a layer formed on or without a filler formed on the anti-glare layer 12, that is, the anti-glare layer is composed of two layers.

As the substrate 11, for example, a transparent plastic film is used. As such a film, a known polymer film can be used. In particular, the polymer film is triacetyl cellulose, polyester, polyethylene terephthalate (PET), polyimide (PI), polyamide, aramid, polyethylene, polyacrylate, polyethersulfone, polysulfone, diacetyl cellulose, polypropylene, It may be appropriately selected from films composed of known resins such as polyvinyl chloride, acrylic resin, polycarbonate, epoxy resin, urea resin, urethane resin and melamine resin. The substrate is not limited to the film, and for example, a sheet or plate composed of transparent plastic can be used.

As for the thickness of the substrate 11, there is no particular limitation, and the thickness is appropriately selected. From the standpoint of achieving excellent productivity, the thickness of the substrate is preferably 38 to 100 m, but the thickness is not limited to this range.

(2-2) Method for manufacturing anti-glare film

Next, a method for producing an anti-glare film according to a second embodiment of the present invention will be described. To prepare a paint having dissipated fine particles 13, a solvent is first mixed into, for example, the aforementioned ionizing radiation curable resin, fine particles 13 and optionally a light stabilizer, an ultraviolet light absorber, an antistatic agent, a flame retardant, an antioxidant, or the like. do. For the solvent, there is no particular limitation, but an organic solvent such as t-butanol, toluene, methyl ethyl ketone (MEK) or isopropyl alcohol (IPA) can be used.

The prepared paint is then applied substantially uniformly to the substrate 11 described above. As for the method for applying the paint, there is no particular limitation, but a known coating method can be used. Examples of coating methods are microgravure coating method, wire bar coating method, direct gravure coating method, mold coating method, dipping coating method, spray coating method, reverse-roll coating method , Curtain coating method, comma coating method, knife coating method and spin coating method.

Regarding the thickness of the applied paint, the solids content of the paint is appropriately controlled so that the average thickness of the applied paint is 3 to 30 µm, preferably 4 to 14 µm. If the thickness is smaller than the above range, it is difficult to obtain the desired hardness, and if the thickness is larger than the average range, the final film is likely to experience significant curling.

After coating, the applied paint is dried at high temperature to volatilize the solvent. Convection caused in the paint during drying may form Bernard Cells, such that the surface of the antiglare layer 12 may have a gently sloped uneven portion with a suitable substrate. In the anti-glare film 2 according to the second embodiment, the desired surface shape is, for example, not only to uniformly disperse the individual fine particles 13, but also by convection to form one diffusing element 13. Is obtained by allowing the agglomeration to be appropriate. The drying temperature and drying time may be appropriately determined depending on the boiling point of the solvent contained in the paint. In such a case, it is preferable to select the drying temperature and the drying time so that the substrate 11 does not undergo deformation due to heat shrinkage while considering the heat resistance of the substrate 11. It is also desirable to control the dry state or the like so that proper convection is caused in the ionizing radiation curable resin to produce the desired surface shape.

The drying step and the curing step are described in detail below.

The paint applied to the substrate 11 is first dried at a predetermined temperature such that the fine particles 13 are condensed in the paint so as to agglomerate appropriately in the in-plane direction by convection to cause two-dimensional agglomeration. In this case, the solvent is volatilized and Bernard lattice is formed on the surface of the applied film. When the fine particles 13 are laminated to each other in the thickness direction of the coated film to form three-dimensional aggregation, a component having an unfavorably sharp angle is formed on the surface of the anti-glare layer, thus increasing the appearance of turbidity.

As used herein, the term "bernard lattice" refers to a surface structure formed by convection or convection caused by paint in the drying step of a solvent. All surface structures formed during the treatment for drying of the solvent are referred to herein as "bernard gratings" and they have any shape and are not limited to tubular structures.

The degree of cohesion of the fine particles 13 can be selected, for example, by appropriately controlling the surface tension of the solvent and the surface energy of the fine particles 13.

The resin contained in the paint is also preferably liquid after drying of the paint. In such a case, a meniscus can be formed between the Bernard gratings, making it possible to produce gently sloped fine uneven portions on the surface of the applied film.

As for the dry state, there is no particular limitation, but air drying or artificial drying in which the drying temperature or drying time is controlled may be employed. When the air stream is directed to the surface of the paint during drying, it is desirable that no wind wrought pattern occurs on the surface of the applied film. If a wind pattern is generated, the desired smoothly inclined fine uneven portions are undesirably formed in the anti-glare surface layer, making it difficult to achieve both anti-glare characteristics and high contrast.

Next, the dried resin of the base material 11 is cured by, for example, ionizing radiation or heat. Thus, a waviness with a large period is formed such that one two-dimensional aggregation continues on one acid. That is, fine irregularities having a wider period and gentle inclination than the irregularities in the continuously produced film are formed on the surface of the anti-glare layer 12.

Examples of curing energy sources used for curing the ionizing radiation curable resin to form the anti-glare layer 12 include electron beams, ultraviolet light, visible light and gamma rays, but ultraviolet light is preferable in view of manufacturing equipment. For the ultraviolet light source, there is no particular limitation, but a high pressure mercury lamp, a metal halide lamp, or the like is appropriately selected. For the total dose, the total dose can be appropriately selected so that the resin used is cured and the resin and substrate 11 are not yellowing. The irradiation atmosphere may be appropriately selected depending on the curing of the resin, and the irradiation may be performed in an inert atmosphere of nitrogen gas, argon gas or the like or in air.

The anti-glare film 1 prepared by the above-described method has the specific diffuse reflection characteristic as described above, and thus suppresses the expression of turbidity while achieving the anti-glare characteristic. The anti-glare film also has a certain spacing between the diffusion elements formed on the surface of the anti-glare layer 12, thus reducing the appearance of rough surface. Therefore, by using the anti-glare film 1 in a display device such as a liquid crystal display, a plasma display, an electroluminescence display or a CRT display, a display having improved visibility by achieving the best anti-glare property and the highest contrast is realized. Can be.

(3) Third embodiment

(3-1) Composition of the anti-glare film

As shown in FIG. 4, the anti-glare film 1 according to the third embodiment of the present invention includes an anti-glare layer 12 formed on the substrate 11, and a plurality of protrusions are formed on the surface of the anti-glare layer 12. It is formed as a diffusing element of, and the surface collectively has fine uneven portions. Fine irregularities on the surface of the antiglare layer 12 are formed by a shape transfer method using a replicated master prepared from a mother mold formed by microfabrication. The mean spacing between the substrate 11, the diffuse reflection characteristic and the diffuser elements of the third embodiment of the present invention is similar to that of the first and second embodiments of the present invention, and thus description thereof is omitted.

The anti-glare layer 12 of the third embodiment of the present invention is formed of a resin containing an ionizing radiation curable resin or a thermosetting resin similar to that of the first and second embodiments of the present invention. Preferable irregularities of the anti-glare layer 12 are obtained by using a replica master described later for transferring the irregularities on the mold surface. The anti-glare layer 12 does not need to include the fine particles 13, but may include them in order to finely control the haze or the surface shape.

(3-2) Method for manufacturing anti-glare film

The method for manufacturing the anti-glare film 1 according to the third embodiment of the present invention is described below with reference to Figs. 7A to 7E.

Process for processing mother mold

First, the base material to be processed is prepared. Examples of base material shapes include substrate shapes, sheet shapes, film shapes, and block shapes. Examples of the material of the base material include plastic, metal and glass. Next, the base material is a mask image forming method using, for example, a KrF excimer laser, a pressing method, a forming stamper, or the like, to obtain a pattern on the surface of the base material fine uneven portion corresponding to the surface of the anti-glare layer 12. , A machining method, a sandblasting method, a wet etching method, or the like is used to obtain a mother mold 21 having an inverse fine concave-convex portion in the shape of the anti-glare layer 12 as shown in Fig. 7A. The surface of the mother die 21 has fine uneven portions so that the anti-glare film 1 according to the third embodiment of the present invention can achieve diffuse reflection characteristics similar to those of the first and second embodiments of the present invention. Preferably it has an average hill-bone spacing Sm which is 300 micrometers or less, More preferably, it is 220 micrometers or less.

Processing to Prepare the Replication Master

Next, an electroconductive film is formed in the fine uneven part of the above-mentioned mother metal mold | die 21 by the electroplating method, for example. The conductive film is a metal film composed of a metal such as nickel. Next, the mother die 21 having the electrically conductive film formed thereon is set in the electroforming apparatus, and a metal plating layer such as a nickel plating layer is formed in the electrically conductive film by, for example, an electrolytic plating method. Then, the metal plating layer is released from the mother mold 21, and has a shape of inverse fine unevenness in the mother mold 21 as shown in Fig. 7B.

Then, the replica master 22 obtained as described above is subjected to a surface treatment, and a metal plating layer such as a nickel plating layer is formed on the fine uneven portion of the final replica master by, for example, an electrolytic plating method. The metal plating layer is then released from the replica master 22 and a replica master 23 having the same fine concave-convex portions as in the mother mold 21 as shown in Fig. 5C is obtained.

If the mother mold is composed of an organic substrate or the like that is easily damaged, the child mold and the grand child mold are prepared from the mother mold as described above, and the grand child mold uses the child mold even if the mother mold is damaged while releasing the mother mold. Can be prepared in large quantities. On the other hand, if the mother mold is not damaged and the child mold can be prepared repeatedly from the mother mold, the mother mold is processed to have the same shape as the anti-glare layer and the final reverse child mold can be used as the transfer mold.

Treatment to prepare an antiglare layer

Next, photosensitive resin, such as an ultraviolet curable resin, flows into the fine uneven part of the replica master 23 obtained by the above-mentioned process. As the photosensitive resin for forming the anti-glare layer 12, for example, a resin similar to that used in the first embodiment of the present invention can be used. The fine concave-convex portion of the anti-glare layer 12 is obtained by the shape transfer, and therefore, it is not necessary to add fine particles to the photosensitive resin, but fine particles may be added to the photosensitive resin in order to finely control the haze or the surface shape.

Then, as shown in FIG. 7D, the substrate 11 as the supporting substrate is placed on the replica master 23. Then, a force is applied to the substrate 11 by, for example, a rubber roller so that the thickness of the photosensitive resin is uniform. Then, for example, the photosensitive resin is cured by irradiating the substrate 11 with a light beam such as, for example, ultraviolet light. Then, as shown in FIG. 5E, the cured photosensitive resin is released from the replica master 23. Therefore, the anti-glare layer 12 is formed on one peripheral surface of the substrate 11, and the anti-glare film 1 having the diffuse reflection characteristic as described above is prepared.

8 is a diagram showing an example of the configuration of a liquid crystal display device using the anti-glare film 1 according to the third embodiment of the present invention. The liquid crystal display device includes a liquid crystal panel 31 and a light source 33 provided below the liquid crystal panel 31 as shown in FIG. 8, and the liquid crystal panel 31 has an anti-glare film 1 on the display side. .

The light source 33 supplies light to the liquid crystal panel 31 and has, for example, a fluorescent lamp FL, a field discharge EL or a light emitting diode LED. The liquid crystal panel 31 spatially modulates the light supplied by the light source 33 to display the information. Polarizing sheets 32a and 32b are provided on two surfaces of the liquid crystal panel 31. The polarizing sheet 32a and the polarizing sheet 32b allow one of the polarizing components perpendicular to the incident light to pass through the sheet frame and the other to be absorbed and blocked. The polarizing sheet 32a and the polarizing sheet 32b are arranged, for example, so that their transmission axes may be perpendicular to each other.

The anti-glare film 1 according to the third embodiment of the present invention has a specific diffuse reflection characteristic as described above, and thus suppresses the expression of turbidity while achieving the anti-glare characteristic. In addition, the anti-glare film has a certain spacing between the diffusion elements formed on the surface of the anti-glare layer 12, and hence the rough appearance is reduced. Therefore, by using the anti-glare film 1 of the liquid crystal display device, the image displayed on the liquid crystal display device can be improved visibility.

Yes

Hereinafter, embodiments of the present invention will be described in more detail with reference to the following examples which are not to be construed to limit the scope of the present invention. Examples 1 to 7 and 9 correspond to the second embodiment of the present invention, and Example 8 corresponds to the third embodiment of the present invention.

Example 1

Raw materials having the composition for paints shown below are mixed together and stirred by a magnetic stirrer for 1 hour, and then the final paint is manufactured by Fuji Photo Film Co., Ltd. Sold] is applied to one surface of triacetylcellulose (TAC) having a thickness of 80 μm.

(The composition of the paint)

100 parts by weight of a polyfunctional monomer

5 parts by weight of polymer

3 parts by weight of a photopolymerization initiator [IRGACURE 184 manufactured and sold by CIBA-GEIGY]

Solvent (t-butanol) 153 parts by weight

10 parts by weight of crosslinkable styrene beads SBX6 [manufactured and sold by SEKISUI PLASTICS CO., LTD.]

After application, the applied paint was dried in a drying oven at 80 ° C. for 2 minutes, and then with ultraviolet light of 100 mJ / cm 2 to obtain the anti-glare film of Example 1, wherein the anti-glare layer had a dried thickness of 11.8 μm. It hardens | cures by irradiating.

Example 2

The anti-glare film of Example 2 changes the amount of crosslinkable styrene beads SBX6 [manufactured and sold by SEKISUUI PLASTICS CO., LTD.] To 3 parts per weight and the dry thickness of the anti-glare layer Obtained in substantially the same manner as in Example 1, except that it was 11.0 μm.

Example 3

In the anti-glare film of Example 3, the amount of crosslinkable styrene beads (SBX6: manufactured by Sekisui Plastic Co., Ltd.) was changed to 5 parts by weight, the amount of solvent (t-butanol) was changed to 156 parts by weight, and the antiglare layer was dried. It was obtained in substantially the same manner as Example 1 except that the thickness was 9.4 탆.

Example 4

The anti-glare film of Example 4 was used instead of the crosslinkable styrene beads (SBX6: manufactured by Sekisui Plastic Co., Ltd.) 3 parts by weight of crosslinkable styrene beads (SBX4: manufactured by Sekisui Plastic Co., Ltd.), and the dried thickness of the antiglare layer was 4.7. Obtained in substantially the same manner as Example 1 except that it was μm.

Example 5

In the anti-glare film of Example 5, 5 parts by weight of the crosslinkable styrene beads (SX500: manufactured by Sosei Chemical Industry Co., Ltd.) was used instead of the crosslinkable styrene beads (SBX6 manufactured by Sekisui Plastics Co., Ltd.), and the amount of the solvent (t-butanol) 156 parts by weight, and was obtained in substantially the same manner as in Example 1 except that the dried thickness of the antiglare layer was 9.7 μm.

* Example 6

In Example 1, 10 parts by weight of crosslinkable styrene beads (SBX6 (manufactured by Sekisui Plastic Co., Ltd.) and 163 parts by weight of a solvent (t-butanol) were mixed together, and the anti-glare film having a dried thickness of the anti-glare layer was 12.3 μm. Got. Then, the coating material manufactured by mix | blending the raw material which has a composition for coating materials shown below to the resultant anti-glare film was apply | coated, and the anti-glare film of Example 6 which has two layers was obtained.

(The composition of the paint)

100 parts by weight of polyfunctional monomer

5 parts by weight of polymer

Photopolymerization initiator [IRGACURE 184: CIBA-GEIGY manufacture and sale] 3 parts by weight

Solvent (t-butanol) 149 parts by weight

Example 7

The anti-glare film of Example 7 was coated on one surface of polyethylene terephthalate (PET: COSMOSHINE A4300, manufactured by TOYOBO Co., Ltd.) having a thickness of 100 μm, and the anti-glare layer had a dried thickness of 10.9 μm. Except that it was obtained in substantially the same manner as in Example 2.

Example 8

A mother die was produced by a mask imaging method using a KrF excimer laser, a nickel plating layer was formed on the model, and then peeled off from the model, thereby producing a first replica die. Thereafter, a nickel plating layer was formed on the first replica die, and then peeled off from the first replica die, thereby producing a second replica die. A paint having the composition shown below is applied to the second replica mold, and a polyethylene terephthalate film [PET: COSMOSHINE A4300, manufactured by TOYOBO Co., Ltd.] having a thickness of 75 μm is superimposed on the paint, and a rubber roller By this, a load of 1 kg is applied to the film on the paint, so that the thickness of the paint becomes uniform. Subsequently, 500 mJ / cm <^2> ultraviolet-rays were irradiated to the polyethylene terephthalate (PET) film, and after hardening | curing an ultraviolet curable resin, an ultraviolet curable resin was peeled off from a 2nd replication die, and the anti-glare film of Example 8 was obtained. The dried thickness of the antiglare layer was 5.5 μm.

(The composition of the paint)

100 parts by weight of polyfunctional monomer

5 parts by weight of polymer

Photopolymerization initiator [IRGACURE 184: CIBA-GEIGY manufacture and sale] 3 parts by weight

Solvent (t-butanol) 149 parts by weight

Example 9

An anti-glare film was obtained in substantially the same manner as in Example 1 except that a raw material having a paint composition shown below was blended and the dried thickness of the anti-glare layer was 7.3 μm.

(The composition of the paint)

100 parts by weight of polyfunctional acrylic oligomer

3 parts by weight of a photopolymerization initiator (IRGACURE 184: Chiba-Gauge Co., Ltd. sales)

150 parts by weight of a solvent (methyl isobutyl ketone: MIBK)

Propylene Glycol Monomethyl Ether (PGM) 37 parts by weight

Silica Beads [SS50B: TOSOH Silica Co., Ltd.]

Dispersant [DOPA15: Shin-Etus Chemical Co., Ltd. manufacture and sale] 10 parts by weight

Comparative Example 1

The anti-glare film of Comparative Example 1 was obtained in substantially the same manner as Example 2 except that the dried thickness of the anti-glare layer was 6.8 μm.

Comparative Example 2

The anti-glare film of Comparative Example 2 was obtained in substantially the same manner as Example 2 except that the dried thickness of the anti-glare layer was 7.6 μm.

Comparative Example 3

The anti-glare film of Comparative Example 3 was used instead of cross-linkable styrene beads (SBX6 (manufactured by Sekisui Plastics Co., Ltd.), 3 parts by weight of cross-linkable styrene beads (SX500: manufactured by Soken Chemical Industry Co., Ltd.) and dried of the anti-glare layer. Obtained in substantially the same manner as Example 1 except that the thickness was 8.5 μm.

Comparative Example 4

In the anti-glare film of Comparative Example 4, 5 parts by weight of cross-linkable styrene beads (SX500: manufactured by Soken Chemical Industry Co., Ltd.) was used instead of cross-linkable styrene beads (SBX6 manufactured and sold by Sekisui Plastic Co., Ltd.), and the anti-glare layer was dried. It was obtained in substantially the same manner as Example 1 except that the thickness was 11.2 mu m.

Comparative Example 5

In the anti-glare film of Comparative Example 5, 5 parts by weight of crosslinkable styrene beads (SBX12: manufactured by Sekisui Plastic Co., Ltd.) was used instead of crosslinkable styrene beads (SBX6 manufactured by Sekisui Plastic Co., Ltd.), and the dried thickness of the antiglare layer was 18.7 Obtained in substantially the same manner as Example 1 except that it was μm.

About each anti-glare film produced in Examples 1-9 and Comparative Examples 1-5, the optical characteristic was evaluated by the method shown below.

(Evaluation of diffuse reflection characteristic)

In order to suppress the back surface reflection effect and to measure the diffuse reflection characteristics of the anti-glare film itself, the back surface of each of the anti-glare films produced in Examples 1 to 9 and Comparative Examples 1 to 5 adhered to the black glass through the adhesive. It became. The diffuse reflection characteristic is -5 ° with a specular reflection direction of 0 ° in a direction of -5 ° with respect to the sample plane using a goniophotometer (manufactured by GP-1-3D OPTEC Co., Ltd.). In the range from 30 ° to 30 ° to evaluate the reflected light intensity under dark conditions. At this time, the luminance meter of the goniometer has a 2 ° field of view.

Graphs showing the diffuse reflection characteristics of Example 1, Example 2 and Comparative Example 2 are shown in FIG. In Fig. 9, L1 corresponds to Example 1, L2 corresponds to Example 2, and L3 corresponds to Comparative Example 2. Graphs showing the diffuse reflection characteristics of Examples 3, 6 and Comparative Example 4 are shown in FIG. In Fig. 10, L4 corresponds to Example 3, L5 corresponds to Example 6, and L6 corresponds to Comparative Example 4. The evaluation contents of the diffuse reflection characteristics are as follows. If l (α) is the intensity of the reflected light at an arbitrary angle α and I (α + 1) is the intensity of the reflected light in the wide-angle direction by 1 ° from α, the I (α + 1) / l (α) ratio is determined. The maximum value of the reflected light intensity ratio was determined as the maximum intensity change per degree. The full widths of the angles at the reflected light intensities of 1/2, 1/100 and 1/1000 with respect to the peaks of the reflected light intensities were individually determined. Gain was measured in the specular reflection direction of each of the anti-glare films of Examples 1 to 9 and Comparative Examples 1 to 5 using the intensity of the light reflected in the specular reflection direction measured as the same by using a standard diffusion plate made of barium sulfate. It was determined by normalizing the reflected light intensity in the 20 ° direction.

[Measurement of haze]

Haze was measured using the haze meter (HM-150: Murakami Color Technology Research Institute manufacture) under the measurement conditions described in JIS K7136. Haze was measured for the anti-glare films of Examples 1 to 9 and Comparative Examples 1 to 5, and the haze was obtained for the anti-glare film obtained by attaching an adhesive having a haze of 1% or less to the anti-glare layer surface of the anti-glare film described above. It was measured and the latter was defined as internal haze, and the difference between the former and the latter was determined as surface haze.

(Measurement of the mean spacing of diffusion elements)

For each of the anti-glare films of Examples 1 to 9 and Comparative Examples 1 to 5, the surface roughness was used with a fully automatic fine shape measuring instrument (SURFCORDER ET4000A manufactured by Kosaka Research Institute Co., Ltd.) under the measurement conditions described in JIS BO601-1994. And roughness curves were obtained from the two-dimensional cross-sectional curves. As the roughness parameter, the average length Sm of the contour curve elements was calculated and determined to determine the average spacing between the diffusion elements.

(Evaluation of anti-glare)

In each of the anti-glare films of Examples 1 to 9 and Comparative Examples 1 to 5, the back surface of the anti-glare film was black glass through the adhesive in order to suppress the influence of the back reflection and to evaluate the anti-glare property of the anti-glare film itself. Attached to. Subsequently, a fluorescent lamp having two fluorescent lamps with little change in contrast arranged in parallel was used as the light source, and the reflection in each anti-glare film was checked by visual observation from the specular reflection direction, so that the reflection of the fluorescent lamp was It was evaluated according to the criteria of.

A: The contour of the fluorescent lamp cannot be observed (two fluorescent lamps are observed with a single light source)

B: Fluorescent lamps may be perceived to some extent, but the outlines are blurred

C: Fluorescent lamp is reflected directly

(Evaluation of white muddiness)

Turbidity is felt by detecting diffused light diffused and reflected at the anti-glare layer surface as a light source such as fluorescent lighting. Therefore, the value measured quantitatively was used as turbidity by simulating the preceding phenomenon using a commercially available spectrocolorimeter. The specific method of measuring the turbidity is as follows. First, with respect to each anti-glare film produced in Examples 1 to 9 and Comparative Examples 1 to 5, in order to suppress the influence of the back reflection and to evaluate the diffuse reflection of the anti-glare film itself, the back surface was applied to the black glass through the adhesive. Attached. Subsequently, using an integrated ball spectrophotometer (SP64: sold by X Light Co., Ltd.), diffused light was irradiated onto the surface of each anti-glare film and the reflected light was placed on a detector positioned in a direction of 8 ° to the normal direction of the anti-glare film. D / 8 ° optical system measured by Regarding the measured value, the SPEX mode in which only the diffuse reflection component is detected except for the specular reflection component was employed, and the measurement was performed at a detection viewing angle of 2 °. Experiments confirmed that there was a correlation between the turbidity measured by the previous method and the visually felt turbidity.

For each of the anti-glare films produced in Examples 1 to 9 and Comparative Examples 1 to 5, the back surface was attached to a black acrylic sheet (ACRYLITE L 502: manufactured by Mitsubishi Rayon Co., Ltd.) through an adhesive, and to the resulting anti-glare film. The turbidity in was measured in the same manner as in the measurement method using black glass. The turbidity measured for the black acrylic sheet without the anti-glare film was 0.2.

The correlation between the turbidity measured for the antiglare film with black glass and the turbidity measured for the antiglare film with the black acrylic sheet is described with reference to Table 1 and FIG.

Table 1

Turbidity for samples with black glass sheets and samples with black acrylic sheets for samples 1 to 14 of the antiglare film obtained by appropriately controlling the thickness and particle diameter by varying the turbidity by the same production method as in Example 1. The measurement results are shown in Table 1. Further, in relation to the turbidity for the sample with the acrylic sheet attached, the value determined by calculating using a regression line obtained from the correlation between the black glass sheet and the black acrylic sheet is shown in Table 1. do. As observed from Table 1, values close to the measured value can be calculated and obtained.

As shown in Fig. 9, the regression line from the correlation between the black glass and the black acrylic sheet shows the black acrylic sheet bonded in the turbidity and the longitudinal coordinate for the sample having the black glass bonded in the abscissa. Eggplants are obtained by plotting turbidity for a sample. In FIG. 9, when the turbidity degree for the sample with the glass sheet is taken x and the turbidity degree for the sample with the acrylic sheet is taken y, a regression analysis line represented by the following formula y = 1.1039x-0.4735 Is obtained and the determining coefficient (R ² ) is 0.9909.

From the foregoing, it can be seen that there is a close correlation between the turbidity measured using the black glass and the turbidity measured using the black acrylic sheet.

(Evaluation of the rough appearance)

In each of the anti-glare films produced in Examples 1 to 9 and Comparative Examples 1 to 5, the back surface of the anti-glare film was black glass through an adhesive in order to suppress the influence of the back reflection and evaluate the rough appearance of the anti-glare film. Attached to. Subsequently, the anti-glare film is irradiated with light in a direction of about 30 ° to the anti-glare film normal using a light box (manufactured by Hakuba Photo Industries Co., Ltd.) as a flat light source, and the reflection in each anti-glare film is specularly reflected. It was checked by visual observation from the direction, and the rough appearance was evaluated according to the following criteria.

(Double-circle): A rough appearance is not visually recognized even about 50 cm from an anti-glare film.

○: The rough appearance is not visually recognized at the lm position from the anti-glare film, but the rough appearance is visually recognized at the position of about 50 cm from the film.

X: The rough appearance was visually recognized at a 1 m position from the anti-glare film.

The results of the optical property evaluation for Examples 1 to 9 and Comparative Examples 1 to 5 are shown in Table 2. Regarding the turbidity, the evaluation results for the anti-glare film with black glass and the results for the anti-glare film with the black acrylic sheet bonded are shown.

Table 2

Note the maximum intensity change per degree shown in Table 2. In each of Examples 1 to 9 where the maximum intensity change per degree is greater than 0.1, the contours of the fluorescent lamps are not clear in the anti-glare evaluation, so that each film corresponds to the class B, which has a suitable anti-glare property. Able to know. On the contrary, in Comparative Example 3 and Comparative Example 4 in which the maximum intensity change per 1 degree is 0.1 or less, reflection of fluorescent illumination is observed in anti-glare evaluation, and a film does not have satisfactory anti-glare property. From the previous results, it was found that the maximum intensity change per 1 ° was greater than 0.1 in order to achieve anti-glare. In Comparative Examples 1 and 2 in which the maximum intensity change per degree was greater than 0.1, the films had excellent anti-glare properties, but they had a gain of 0.02 or more at 20 degrees, and had a strong turbidity. From this, it turned out that it is preferable that the maximum intensity change per 1 degree is 0.6 or less.

Next, note the full width of the angle at 1/100 reflected light intensity. In each of Examples 1 to 9 in which the full width of the angle was 6.0 degrees or more, each film achieved appropriate anti-glare property. On the contrary, in Comparative Examples 3 and 4 in which the full width of the angle was less than 6 °, the reflection of the fluorescent light was observed in the anti-glare evaluation by visual observation, and the film did not have satisfactory anti-glare property. On the contrary, in Comparative Example 1 and Comparative Example 2 in which the full width is larger than 28.0 °, the film has excellent anti-glare property, but has a gain higher than 0.02 at 20 ° and a strong turbidity. From the previous results, it was found that in order to achieve anti-glare, the full width of the angle should be 6.0 ° to 28.0 ° at the 1/100 reflected light intensity.

Next, note the full width of the angle at 1/1000 reflected light intensity. In each of Examples 1 to 9 in which the full width of the angle was 10.0 ° or more, each film achieved appropriate anti-glare property. On the contrary, in Comparative Examples 3 and 4 in which the full width of the angle was less than 10.0 °, the reflection of the fluorescent light was observed in the anti-glare evaluation by visual observation, and the film did not have satisfactory anti-glare property. On the contrary, in Comparative Example 1 and Comparative Example 2 in which the full width is larger than 45.0 °, the film has excellent anti-glare property, but has a gain higher than 0.02 and strong turbidity at 20 °. From the previous results, it was found that in order to achieve anti-glare, the full width of the angle should be 10.0 ° to 45.0 ° at 1/1000 reflected light intensity.

Note the full width of the angle at half reflected light intensity (half band width). Only Comparative Example 1 satisfies the requirement disclosed in Japanese Patent Laid-Open No. 2002-365410, in which the half width of the reflected light intensity peak is 7 ° or more, and the film achieves excellent anti-glare property, but the black acrylic sheet is attached. The film has a turbidity greater than 1.7. From this, it was found that it was difficult to achieve both good anti-glare and reduced cloudiness. In addition, from the comparison between Comparative Examples 3 and 4 having insufficient anti-glare and Example 5 in which proper anti-glare was obtained, no relationship to half-value width was found between them. From the above, it was found that only a film having a specific full width of the angle at 1/2 reflected light intensity could not achieve anti-glare property. The reason for this is that there exists a correlation between the human visual sensitivity and the logarithm of the light intensity, and it is considered that the light sensitivity must be gradually reduced to an intensity of 1/100 or 1/1000.

The anti-glare films of Examples 1 to 9, each having a gain of 0.02 or less at 20 ° and bonded with a black acrylic sheet, respectively, had a turbidity of 1.7 or less in terms of the turbidity evaluated at d / 8 ° reflectance excluding the specular reflection component. Had The anti-glare films of Examples 1 to 9 each attached with a black acrylic sheet had a haze of less than 1.7 and had a reduced black reflectance, so that black was observed when the film was actually used on the display surface. In addition, the anti-glare films of Examples 2 and 4 to 9 each bonded with a black acrylic sheet had a turbidity of 1.2 or less, more reduced black reflectance, and improved contrast, thereby imparting reality to the image. On the contrary, the anti-glare films of Comparative Examples 1 and 2 having a gain of 0.02 or more at 20 ° had strong turbidity.

In strong comparative example 1 and comparative example 2 of turbidity, surface haze is larger than 5.0%. From this, it turned out that it is preferable that surface haze is 0%-5.0%. In each of Examples 2 to 9, the surface haze is 3.0% or less. From this, it turned out that it is more preferable that surface haze is 0%-3.0%. On the other hand, the internal haze is not particularly specified and is determined by adding fine particles necessary to obtain a surface shape capable of achieving desired diffuse reflection characteristics.

Next, note the average spacing between diffusion elements. For each of the anti-glare films of Examples 1 to 9 having an average interval of 300 μm or less, the rough appearance was not recognized in reflection at the 1 m position from the anti-glare film. In particular, each of the anti-glare films of Examples 1, 2, 4 to 6, 8, and 9 having an average interval of 220 μm or less has a high precision such that rough appearance is not recognized even at a position of about 50 cm from the anti-glare film. It had one surface property. In contrast, for the anti-glare film of Comparative Example 5 having an average spacing greater than 330 mu m, the rough appearance was recognized and the anti-glare film did not have a precise surface. In addition, each has an average spacing of 300 μm or less, but the maximum intensity change per degree is 0.1 to 0.6, the full width of the angle at 1/100 reflected light intensity is 6.0 ° to 28.0 °, or at 1/1000 reflected light intensity. Serious anti-glare appearance was recognized for the anti-glare films of Comparative Examples 3 and 4, which did not satisfy the conditions for the diffuse reflection characteristic with the full width of the angle of 10.0 ° to 45.0 °. It is thought that the reason is that irregularities are caused in various places on a relatively flat surface.

The rough appearance is easily recognized when the surface of the containing fine particles protrudes greatly from the anti-glare layer made of the ultraviolet curable resin. Therefore, it was further improved by reducing the steeply inclined portion of the particles by covering the particle surface with an ionizing radiation curable resin or the like. In addition, for the same purpose, the classification of the particles added to remove large diameter particles also worked.

In order to confirm image light, the anti-glare films of Examples 1 to 9 and Comparative Examples 1 to 5 were individually applied to the image display device. In the anti-glare film of Comparative Example 5, scintillation referred to as surface glare was remarkably observed, and scintillation was hardly observed in each of the anti-glare films of Examples 1 to 9.

From the above results, as a diffuse reflection characteristic, the ratio of the reflected light intensity at any angle of less than 10 ° from the specular reflection direction and the reflected light intensity shifted in the wide angle direction by 1 ° from an arbitrary angle, and reflected in a direction of 20 ° or more from the specular reflection direction It was found that the antiglare film having a specific gain of light has a turbidity suppressed while achieving the antiglare property. Similarly, an anti-glare film having a specific full width of an angle at a reflected light intensity of 1/100 or 1/1000 with respect to a peak of reflected light intensity and a specific gain of light reflected in a direction of 20 ° or more from the specular reflection direction achieves anti-glare property It was found that it had a reduced turbidity. In addition to the above-described diffuse reflection characteristics, it was found that the anti-glare film having a specific average distance between the diffusion elements has a reduced rough appearance.

As mentioned above, although the first, second and third embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and may be changed and changed based on the technical idea of the present invention. For example, the numerical values, materials, and procedures mentioned in the foregoing embodiments are only examples, and other numerical values, materials, and procedures different from these may be used as necessary.

For example, in the second embodiment of the present invention, an example in which fine concavo-convex is formed on the surface due to convection caused in the resin containing fine particles has been described. However, as long as the Bernard cell is formed in the resin by convection, Resin that does not contain fine particles can be used.

In the third embodiment of the present invention, an example in which an anti-glare film is used in a liquid crystal display has been described, but the display device is not limited to a liquid crystal display, and various displays such as plasma displays, electric field light emitting displays, and cathode ray tube (CRT) displays. It may be applied to the device.

In the first and third embodiments of the present invention, an example in which fine irregularities are formed on the surface of the anti-glare film by the criminal transfer method has been described, but the irregularities are, for example, sandblasted method, laser beam machining on the substrate surface. It may be formed on the surface by applying a treatment by a method, a wet etching method, or the like.

It is apparent to those skilled in the art that various modifications, combinations, subcombinations, and changes may occur depending on design requirements and other factors, within the spirit of the appended claims or their equivalents.

1 is an enlarged cross-sectional view showing an example of the configuration of an anti-glare film according to a first embodiment of the present invention.

2A-2E are cross-sectional views showing one example of a process for producing an anti-glare film according to a first embodiment of the present invention.

Figure 3 is an enlarged cross-sectional view showing the configuration of an anti-glare film according to a second embodiment of the present invention.

4 is a diagram showing an example of conditions for measuring diffuse reflection characteristics of incident light on a surface at an angle of 5 ° to 30 ° with respect to the normal direction of the anti-glare film according to the second embodiment of the present invention.

5 is a graph showing an example of diffuse reflection characteristics of the anti-glare film according to the second embodiment of the present invention.

6 is an enlarged cross-sectional view showing an example of the configuration of an anti-glare film according to a third embodiment of the present invention.

7A to 7E are cross-sectional views showing one example of the anti-glare film manufacturing process according to the third embodiment of the present invention.

8 is a view showing an example of the configuration of a liquid crystal display device using the anti-glare film according to the third embodiment of the present invention.

9 is a graph showing diffuse reflection characteristics in Examples 1 and 2 and Comparative Example 2. FIG.

10 is a graph showing diffuse reflection characteristics in Examples 3 and 6 and Comparative Example 4. FIG.

Fig. 11 is a graph for explaining the calibration between the degree of turbidity measured using the black acrylic sheet and the degree of turbidity measured using the black glass sheet.

* Description of the symbols for the main parts of the drawings *

1: anti-glare film

11: description

12: anti-glare layer

14: surface

21: mother mold

23: Replication Master

Claims (22)

An anti-glare film having a plurality of diffusion elements formed on the surface, I (α) is the intensity of the reflected light reflected at any angle of 10 ° or less from the specular reflection direction of incident light on the surface having a plurality of diffusing elements thereon at an angle of 5 ° to 30 ° from the normal direction of the surface, and I (α + 1) is an I (α + 1) / I (α) ratio greater than 0.1 to 0.6 when the intensity of reflected light is shifted by 1 ° in the wide-angle direction from the arbitrary angle α, When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the standard diffuser plate, the gain of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light has an optical characteristic of 0.02 or less, Wherein said diffusing element has an average spacing of between 50 and 300 micrometers. The method of claim 1, wherein the surface has a fine concavo-convex shape, The optical characteristic is an anti-glare film mainly defined by a fine concavo-convex shape. The antiglare film of claim 1 wherein the plurality of diffuser elements are provided on a substrate to form an antiglare film. The anti-glare layer of claim 2, wherein the anti-glare layer is composed of a resin in which fine particles having an average particle diameter in a range of 5 nanometers (nm) to 15 micrometers (μm) are dispersed therein. The anti-glare film of claim 4, wherein the fine particles are agglomerated in an in-plane direction such that a fine uneven shape is formed on a surface thereof. The anti-glare film of claim 5 wherein said aggregated fine particles are covered with a resin to form a diffusion element. The anti-glare film of claim 6, wherein the resin comprises at least one of an ionizing radiation curable resin and a thermosetting resin. The anti-glare film of claim 6 wherein the surface of the aggregated fine particles is not exposed or only a portion of the surface of the fine particles located at the tip of the diffusing element is exposed. The anti-glare film of claim 6 wherein the diffusing elements have a meniscus formed therebetween. The anti-glare film of claim 1 having a surface haze of 5.0% or less. A plurality of diffusion elements formed on the surface, It has a full width of 6.0 ° to 28.0 ° at 1/100 reflected light intensity with respect to the peak of the reflected light intensity with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface, When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection light intensity of the standard diffuser plate, it has an optical characteristic, having a gain of 0.02 or less of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light, Wherein said diffusing element has an average spacing of between 50 and 300 micrometers. A plurality of diffusion elements formed on the surface, Has a full width of 10.0 ° to 45.0 ° angle at 1 / 1,000 reflected light intensity with respect to the peak of the reflected light intensity with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface, When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection light intensity of the standard diffuser plate, it has an optical characteristic, having a gain of 0.02 or less of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light, The diffusing element is an antiglare film having an average spacing of 50 to 300 micrometers. Anti-glare film manufacturing method, Forming a fine concavo-convex shape on the surface of the anti-glare film by a shape transfer method, a sand blast method, a laser beam machining method, a wet etching method or a Bernard cell formation method so that a plurality of diffusion elements are formed on the surface; The anti-glare film, Intensity of reflected light in which I (α) is reflected at an angle α of 10 ° or less from the first specular reflection direction of incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface Has an I (α + 1) / I (α) ratio greater than 0.1 to 0.6 when I (α + 1) is the intensity of the reflected light shifted by 1 ° in the wide angle direction from the arbitrary angle α, When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the standard diffuser plate, the gain of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light has an optical characteristic of 0.02 or less, Wherein said diffusing element has an average spacing of between 50 and 300 micrometers. The method of forming a fine concavo-convex shape according to claim 13, wherein the shape transfer method is used. Supplying the resin to the mold, Curing the resin supplied to the mold and peeling the cured resin from the mold. 15. The anti-glare film of claim 14, wherein the method for forming the fine concavo-convex shape further comprises forming the concave-convex shape on the mold by sand blast, wet etching, or laser beam machining before supplying the resin into the mold. Manufacturing method. The method of claim 13, wherein the uneven shape forming step using the Bernard cell forming method, Applying a coating composition comprising fine particles, a resin, and a solvent to a substrate, Generating convection in the coating composition to dry the applied coating composition such that the fine particles aggregate by convection; The anti-glare film manufacturing method comprising the step of curing the dried coating composition. 17. The method of claim 16, wherein in said applied composition drying step, the Bernard cell is formed by convection. Anti-glare film manufacturing method, Forming a fine concavo-convex shape on the surface of the anti-glare film by a shape transfer method, a sand blast method, a laser beam machining method, a wet etching method or a Bernard cell formation method so that a plurality of diffusion elements are formed on the surface, The anti-glare film, It has a full width of 6.0 ° to 28.0 ° at 1/100 reflected light intensity with respect to the peak of the reflected light intensity with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface, When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection light intensity of the standard diffuser plate, it has an optical characteristic, having a gain of 0.02 or less of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light, Wherein said diffusing element has an average spacing of between 50 and 300 micrometers. Anti-glare film manufacturing method, Forming a fine concavo-convex shape on the surface of the anti-glare film by a shape transfer method, a sand blast method, a laser beam machining method, a wet etching method or a Bernard cell formation method so that a plurality of diffusion elements are formed on the surface, The anti-glare film, It has a full width of 10.0 ° to 45.0 ° at 1 / 1,000 reflected light intensity with respect to the peak of the reflected light intensity with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface, When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection light intensity of the standard diffuser plate, it has an optical characteristic, having a gain of 0.02 or less of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light, Wherein said diffusing element has an average spacing of between 50 and 300 micrometers. Display device, A display unit for displaying an image, It includes an anti-glare film formed on the display side of the display unit, The anti-glare film, Having a plurality of diffusion elements on the surface, Of reflected light reflected at an angle α of 10 ° or less from the first specular reflection direction with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface. Has an I (α + 1) / I (α) ratio greater than 0.1 to 0.6 when the intensity is the intensity of the reflected light shifted by 1 ° in the wide-angle direction from the above arbitrary angle α. , When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection intensity of the standard diffuser plate, the gain of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light has an optical characteristic of 0.02 or less, The diffusion element has an average spacing of 50 to 300 micrometers. Display device, A display unit for displaying an image, It includes an anti-glare film formed on the display side of the display unit, The anti-glare film, Having a plurality of diffusion elements on the surface, It has a full width of 6.0 ° to 28.0 ° at 1/100 reflected light intensity with respect to the peak of the reflected light intensity with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface, When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection light intensity of the standard diffuser plate, it has an optical characteristic, having a gain of 0.02 or less of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light, The diffusion element has an average spacing of 50 to 300 micrometers. Display device, A display unit for displaying an image, It includes an anti-glare film formed on the display side of the display unit, The anti-glare film, Having a plurality of diffusion elements on the surface, Has a full width of 10.0 ° to 45.0 ° angle at 1 / 1,000 reflected light intensity with respect to the peak of the reflected light intensity with respect to incident light on the surface having a plurality of diffusing elements at an angle of 5 ° to 30 ° from the normal direction of the surface, When the gain is obtained by normalizing the reflected light intensity to 1 using the specular reflection light intensity of the standard diffuser plate, it has an optical characteristic, having a gain of 0.02 or less of the light reflected in the direction of 20 ° or more from the specular reflection direction of the incident light, The diffusion element has an average spacing of 50 to 300 micrometers.

Images