JP4844254B2 - Anti-glare film and image display device - Google Patents

Description

  The present invention relates to an antiglare (antiglare) film having a low haze while exhibiting excellent antiglare performance, and an image display device including the antiglare film.

  In an image display device such as a liquid crystal display, a plasma display panel, a cathode ray tube (CRT) display, and an organic electroluminescence (EL) display, visibility is significantly impaired when external light is reflected on the display surface. In order to prevent such reflection of external light, TVs and personal computers that emphasize image quality, video cameras and digital cameras used outdoors with strong external light, mobile phones that display using reflected light, etc. In the conventional art, a film layer for preventing the reflection of external light has been provided on the surface of the image display device. This film layer consists of a film that has been subjected to anti-reflection treatment using interference by the optical multilayer film, and anti-glare treatment that scatters incident light by blurring the incident light by forming fine irregularities on the surface. It is divided roughly into the thing which consists of the film which was given. Among these, the former non-reflective film needs to form a multilayer film having a uniform optical film thickness, and thus increases the cost. On the other hand, since the latter anti-glare film can be produced at a relatively low cost, it is widely used in applications such as large personal computers and monitors.

  Conventionally, such an antiglare film has, for example, a resin solution in which a filler is dispersed is applied on a base sheet, and the coating film thickness is adjusted to expose the filler on the surface of the coating film, thereby causing random unevenness on the sheet. It is manufactured by the method of forming on top. However, the antiglare film produced by dispersing such a filler has an unevenness as intended because the arrangement and shape of the unevenness depends on the dispersion state and application state of the filler in the resin solution. There is a problem that it is difficult to obtain, and sufficient anti-glare performance cannot be obtained if the haze is low. Furthermore, when such a conventional anti-glare film is disposed on the surface of an image display device, there is a problem that the entire display surface becomes whitish due to scattered light, and the display becomes cloudy, so-called whitening is likely to occur. It was. In addition, with recent high-definition image display devices, the pixels of the image display device and the surface irregularity shape of the antiglare film interfere with each other, and as a result, a so-called glare phenomenon that the luminance distribution is generated and is difficult to see easily occurs. There was also a problem.

  On the other hand, there is also an attempt to develop anti-glare properties only by fine irregularities formed on the surface of the transparent resin layer without containing a filler. For example, Japanese Patent Application Laid-Open No. 2002-189106 (Patent Document 1) discloses that the ionizing radiation curable resin is cured in a state where the ionizing radiation curable resin is sandwiched between an embossing mold and a transparent resin film. An ionizing radiation curable resin in which fine irregularities are formed in which the average distance between adjacent convex portions on the original 10-point average roughness and the three-dimensional roughness reference surface satisfies predetermined values, respectively, and the irregularities are formed. An antiglare film having a layer provided on the transparent resin film is disclosed.

  In addition, it is also possible to use a film having fine irregularities formed on the surface as a light diffusion layer disposed on the back side of the liquid crystal display device, instead of an antiglare film disposed on the display surface of the display device. It is disclosed in Japanese Laid-Open Patent Publication No. 6-34961 (Patent Document 2), Japanese Unexamined Patent Application Publication No. 2004-45471 (Patent Document 3), Japanese Unexamined Patent Application Publication No. 2004-45472 (Patent Document 4), and the like.

  As a method for forming irregularities on the surface of the film, in Patent Document 3 and Patent Document 4 described above, an embossing roll having a shape obtained by inverting the irregularities is filled with an ionizing radiation curable resin liquid, and the filled resin is subjected to roll intaglio. The transparent base material that runs in synchronization with the rotation direction of the roller is brought into contact, and when the transparent base material is in contact with the roll intaglio, the resin between the roll intaglio and the transparent base material is cured and cured simultaneously with the curing. A method is disclosed in which after the resin and the transparent substrate are brought into close contact with each other, the laminate of the cured resin and the transparent substrate is peeled off from the roll intaglio.

  In such a method, the composition of the ionizing radiation curable resin liquid that can be used is limited, and leveling as when applied by diluting with a solvent cannot be expected, so there is a problem in film thickness uniformity. It is expected that. Furthermore, since it is necessary to directly fill the embossing roll intaglio with the resin liquid, in order to ensure the uniformity of the uneven surface, the embossing roll intaglio requires high mechanical accuracy, and it is difficult to produce the embossing roll. there were.

  Next, as a method for producing a roll used for producing a film having irregularities on the surface, for example, in Patent Document 2, a cylindrical body is made using a metal or the like, and electronic engraving, etching, sandblasting, or the like is formed on the surface. A method of forming irregularities by the above method is disclosed. Japanese Patent Laid-Open No. 2004-29240 (Patent Document 5) discloses a method for producing an emboss roll by a bead shot method, and Japanese Patent Laid-Open No. 2004-90187 (Patent Document 6) discloses an emboss roll. Forming a metal plating layer on the surface of the metal, mirror polishing the surface of the metal plating layer, blasting the mirror-plated metal plating layer with ceramic beads, and peening if necessary A method for producing an embossing roll through the steps is disclosed.

  Thus, in the state where the surface of the embossing roll has been subjected to blasting, the uneven diameter distribution resulting from the particle size distribution of the blast particles occurs, and it is difficult to control the depth of the indentation obtained by blasting. In addition, there is a problem in obtaining an uneven shape having an excellent antiglare function with good reproducibility.

  Further, Patent Document 1 describes that a concavo-convex surface is formed by a sandblasting method or a bead shot method, preferably using a chrome-plated roller on the surface of iron. Furthermore, it is preferable to use the mold surface with the unevenness after applying chrome plating for the purpose of improving durability during use, thereby achieving hardening and corrosion prevention. There is also a statement that it is possible. On the other hand, in each of the examples of Patent Document 3 and Patent Document 4, the surface of the iron core is chrome-plated, subjected to # 250 liquid sandblasting, and then chrome-plated again to form a fine uneven shape on the surface. It is described to do.

  In such an embossing roll manufacturing method, since blasting or shot is performed on chromium plating with high hardness, it is difficult to form unevenness and it is difficult to precisely control the shape of the formed unevenness. Further, as described in Japanese Patent Application Laid-Open No. 2004-29672 (Patent Document 7), the surface of chrome plating is often rough depending on the material and shape of the base, and the surface of the unevenness formed by blasting Since fine cracks generated by chrome plating are formed on the surface, there is a problem that it is difficult to design what kind of irregularities can be formed. Furthermore, since there are fine cracks generated by chrome plating, there is also a problem that the scattering characteristics of the finally obtained antiglare film change in an unfavorable direction. Furthermore, since the finished roll surface changes in various ways depending on the combination of the metal type and plating type on the surface of the embossing roll base material, in order to obtain the required surface irregularities with high accuracy, the metal on the appropriate roll surface is required. There was also a problem that a seed and an appropriate plating type had to be selected. Furthermore, even if the desired surface irregularity shape is obtained, the durability during use may be insufficient depending on the type of plating.

  Japanese Patent Application Laid-Open No. 2000-284106 (Patent Document 8) describes performing an etching process and / or a thin film laminating process after sandblasting a base material. JP-A-2006-53371 (Patent Document 9) describes the formation of irregularities by hitting fine particles against a polished metal surface, and applying electroless nickel plating there to form a mold. It is described that by transferring the surface to a transparent resin film, the antiglare film has excellent antiglare performance while having low haze.

JP 2002-189106 A (Claims 1 to 6, paragraphs 0043 to 0046) JP-A-6-34961 (Claims 1 to 3, paragraph 0024) Japanese Patent Laying-Open No. 2004-45471 (Claim 4, Example 1) Japanese Patent Laying-Open No. 2004-45472 (Claim 4, Example 1) JP 2004-29240 A (Claim 2) JP-A-2004-90187 (Claims 1 and 2) JP 2004-29672 A (paragraph 0030) JP 2000-284106 A (Claim 7, paragraph 0006) JP 2006-53371 A (Claims 1 and 2)

  The present invention is an anti-glare film that exhibits excellent anti-glare performance, has low haze, prevents deterioration of visibility due to whitishness, and does not cause glare when placed on the surface of a high-definition image display device Furthermore, it is an object to provide an image display device to which the antiglare film is applied.

  In Japanese Patent Application No. 2005-351617 filed on Dec. 6, 2005 by the present applicant, fine particles having an average particle size in the range of 15 to 35 μm are applied to the polished metal surface to form irregularities, and the irregular surface It has been proposed that an anti-glare film exhibiting excellent anti-glare performance can be obtained by applying electroless nickel plating to a mold and transferring the uneven surface of the mold to a transparent resin film. Similarly, in Japanese Patent Application No. 2006-62440 filed on Mar. 8, 2006, the surface of the substrate is subjected to copper plating or nickel plating, the plated surface is polished, and fine particles are applied to the polished surface to form irregularities. Proposed that after the process of dulling the uneven shape, by applying chrome plating to the uneven surface, a mold effective for producing an anti-glare film with low haze and excellent anti-glare performance can be obtained. ing. As a result of further research based on these methods, especially the latter method, for example, if the conditions for hitting fine particles are appropriately selected, the regular reflectance is relatively small and the reflection profile has a wide spread. It was found that a dazzling film was obtained, and this antiglare film exhibited even better antiglare performance, and in particular, the change in display image was small even when the viewing angle was changed. And the index which can evaluate the anti-glare performance suitably was also found. The present invention has been completed based on such findings and further various studies.

  That is, the antiglare film according to the present invention has irregularities on the surface, and the reflectance R (30) at a reflection angle of 30 ° is 0.04% or more and 0.2 with respect to light incident at an incident angle of 30 °. %, The reflectance R (40) at a reflection angle of 40 ° is 0.005% or more and 0.02% or less, the reflectance R (50) at a reflection angle of 50 ° is 0.0015% or less, and It satisfies any one of the following requirements (1) to (7).

(1) The value of R (35) / R (30) is not less than 0.4 and not more than 0.8, where R (35) is the reflectance in the direction of a reflection angle of 35 ° with respect to light incident at an incident angle of 30 °. thing,
(2) Arithmetic mean height Pa in an arbitrary cross-sectional curve of the film uneven surface is from 0.09 μm to 0.21 μm,
(3) The maximum cross-sectional height Pt in an arbitrary cross-sectional curve on the film uneven surface is 0.5 μm or more and 1.2 μm or less,
(4) The average length PSm in an arbitrary cross-sectional curve of the film uneven surface is 12 μm or more and 20 μm or less,
(5) When the elevation of each point on the uneven surface of the film is represented by a histogram, the peak of the histogram is the midpoint (50% height) between the highest point (height 100%) and the lowest point (height 0%). ) Around ± 10%
(6) having 150 to 350 convex portions in a 200 μm × 200 μm region;
(7) The average area of the polygon formed when the surface is Voronoi-divided with the vertex of the convex portion of the film surface unevenness as the base point is 100 μm ² or more and 300 μm ² or less.

  It is more effective to satisfy two or more of these, and it is also effective to satisfy all of these requirements. Among these, the requirement that the value of R (35) / R (30) in (1) is 0.4 or more and 0.8 or less is important.

  This anti-glare film can make haze with respect to perpendicular incident light 3% or more and 20% or less. This anti-glare film is a sum of reflection sharpness measured at a light incident angle of 45 ° using three types of optical combs having a dark portion and a bright portion width of 0.5 mm, 1.0 mm and 2.0 mm. Can be made 30% or less.

  This anti-glare film is subjected to copper plating or nickel plating on the surface of the metal, and after polishing the plated surface, bumps are formed on the polished surface to form irregularities and the irregularities are dulled. It is manufactured advantageously by applying chromium plating to the uneven surface to make a mold, transferring the uneven surface of the mold to a transparent resin film, and then peeling the transparent resin film with the uneven surface transferred from the mold. The

  In the production of this mold, the fine particles hitting the polished copper or nickel plating surface are preferably those having an average particle diameter of 10 to 50 μm, particularly spherical, and the pressure at the time of hitting the fine particles is 0 in gauge pressure. It is preferably about 1 to 0.4 MPa. Moreover, it is advantageous to employ an etching process or copper plating for the process of dulling the uneven shape formed by hitting the fine particles. When the etching process is employed, the etching amount is preferably 1 μm or more and 20 μm or less, and more preferably 2 μm or more and 10 μm or less. On the other hand, when copper plating is employed, the thickness is preferably 1 μm or more and 20 μm or less, and more preferably 4 μm or more and 10 μm or less.

  In this method, it is advantageous to use the chrome-plated surface as the uneven surface of the mold without polishing the surface after chrome plating. The thickness of the chromium plating is preferably 1 μm or more and 10 μm or less, more preferably 2 μm or more and 8 μm or less. The transparent resin film that transfers the uneven surface of the mold consists of a transparent base film with a photocurable resin layer formed on it, and is cured while pressing the photocurable resin layer against the uneven surface of the mold. By doing so, the uneven surface of the mold can be transferred to the photocurable resin layer.

  The antiglare film of the present invention can be combined with an image display means such as a liquid crystal display element or a plasma display panel to form an image display device. Therefore, an image display apparatus according to the present invention includes the above-described antiglare film and image display means, and the antiglare film is disposed on the viewing side of the image display means.

  The anti-glare film of the present invention is excellent in anti-glare performance such as suppression of whitish and glare while maintaining a brightness of a display image while having a low haze and exhibiting sufficient anti-reflection and anti-reflection performance. It will be a thing. And the image display apparatus which has arrange | positioned the anti-glare film of this invention is excellent in brightness, anti-glare performance, and visibility.

  Hereinafter, preferred embodiments of the present invention will be described in detail. The antiglare film of the present invention has fine irregularities formed on the surface, and the reflectance R (30) at a reflection angle of 30 ° with respect to light incident at an incident angle of 30 ° is 0.04% or more and 0.0. 2% or less, the reflectance R (40) at a reflection angle of 40 ° is 0.005% or more and 0.02% or less, the reflectance R (50) at a reflection angle of 50 ° is 0.0015% or less, and It satisfies at least one of the following (1) to (7).

(1) The value of R (35) / R (30) is not less than 0.4 and not more than 0.8, where R (35) is the reflectance in the direction of a reflection angle of 35 ° with respect to light incident at an incident angle of 30 °. thing,
(2) Arithmetic mean height Pa in an arbitrary cross-sectional curve of the film uneven surface is from 0.09 μm to 0.21 μm,
(3) The maximum cross-sectional height Pt in an arbitrary cross-sectional curve on the film uneven surface is 0.5 μm or more and 1.2 μm or less,
(4) The average length PSm in an arbitrary cross-sectional curve of the film uneven surface is 12 μm or more and 20 μm or less,
(5) When the elevation of each point on the uneven surface of the film is represented by a histogram, the peak of the histogram is the midpoint (50% height) between the highest point (height 100%) and the lowest point (height 0%). ) Around ± 10%
(6) having 150 to 350 convex portions in a 200 μm × 200 μm region;
(7) The average area of the polygon formed when the surface is Voronoi-divided with the vertex of the convex portion of the film surface unevenness as the base point is 100 μm ² or more and 300 μm ² or less.

  Among these, (1) is a fourth factor related to the reflectance characteristic, and (2) to (7) are factors related to the shape of the surface unevenness.

First, an index that can favorably evaluate the antiglare performance will be described. FIG. 1 is a perspective view schematically showing an incident direction and a reflection direction of light with respect to the antiglare film. In the present invention, with respect to incident light 13 incident at an angle of 30 ° from the normal 12 of the antiglare film 11, the reflectance (that is, the regular reflectance) in the direction of the reflection angle of 30 °, that is, the regular reflection direction 15 is R ( 30) When the reflectance in the direction of the reflection angle of 35 ° is R (35), the reflectance in the direction of the reflection angle of 40 ° is R (40), and the reflectance in the direction of the reflection angle of 50 ° is R (50). R (30) is 0.04% or more and 0.2% or less, R (40) is 0.005% or more and 0.02% or less, and R (50) is 0.0015% or less. In one embodiment, the value of R (35) / R (30) is 0.4 or more and 0.8 or less. By satisfying these requirements, it was found that an anti-glare film having a low haze while exhibiting sufficient anti-glare properties and with reduced whiteness and glare was obtained. In FIG. 1, the reflected light at an arbitrary reflection angle θ is represented by reference numeral 16, and the directions 15 and 16 of the reflected light when the reflectance is measured are planes including the incident light direction 13 and the normal 12. 18.

  FIG. 2 is an example of a graph in which the reflection angle and the reflectance (the reflectance is a logarithmic scale) of the reflected light 16 with respect to the incident light 13 incident at an angle of 30 ° from the normal line 12 of the antiglare film 11 in FIG. It is. Such a graph representing the relationship between the reflection angle and the reflectance, or the reflectance for each reflection angle read from the graph may be referred to as a reflection profile. As shown in this graph, the regular reflectance R (30) is a reflectance peak with respect to incident light 13 incident at 30 °, and the reflectance tends to decrease as the angle deviates from the regular reflection direction.

  Reflection with regular reflectance R (30) of 0.04% or more and 0.2% or less, reflectance R (40) with a reflection angle of 40 ° of 0.005% or more and 0.02% or less, and reflection angle of 50 ° The point that the rate R (50) is 0.0015% or less and the value of R (35) / R (30) is 0.4 or more and 0.8 or less will be described. The shape is such that the regular reflectance R (30) is low, the inclination near the regular reflection angle is small, and the angle at which the reflectance is about 1/10 of the regular reflectance is spread about ± 10 ° from the regular reflection direction. The reflectance on the wide-angle side is kept low while holding. By setting the reflection profile to such a shape, an antiglare film exhibiting excellent antiglare properties while having a low haze is obtained. When the reflection profile does not show such a shape, that is, the inclination near the regular reflection angle is large, and the angle at which the reflectance is about 1/10 of the regular reflectance is about ± 10 ° from the regular reflection direction. When there is no spread, it means that the reflectivity is drastically decreased due to a slight change in angle from the regular reflection direction, and as a result, a reflected image tends to appear.

  Specifically, when an arbitrary light source is reflected on the antiglare film of the present invention, a reflected light amount close to regular reflection light is obtained in a range of regular reflection angle of ± 10 °, and as a result, an image of the light source Can be sufficiently scattered and blurred. On the other hand, when an arbitrary light source is reflected on an anti-glare film that has a large inclination near the regular reflection angle and does not show a widened reflection profile, the light source is drastically changed by slightly changing the angle from the regular reflection direction. The reflected light from the is reduced. This means that the regular reflection light can be clearly distinguished from the surroundings, that is, the reflected light is imaged and reflected.

  About regular reflectance R (30), when it exceeds 0.2%, sufficient anti-glare function will not be obtained and visibility will fall. On the other hand, if the regular reflectance R (30) is too small, it tends to cause whitening, so the content is set to 0.04% or more. About R (40), if it is too large, whitening tends to occur. Therefore, the content is set to 0.02% or less. On the other hand, if R (40) is too small, sufficient antiglare properties will not be exhibited, so the content is made 0.005% or more. About R (50), if it is too large, whitening tends to occur, so the content is set to 0.0015% or less. From the viewpoint of whitishness, R (50) is preferably as small as possible, but practically the lower limit is about 0.0001%. The value of R (35) / R (30) corresponds to the inclination near 30 ° in FIG. 1, that is, the inclination near the regular reflection angle. This is because the reflectance is shown on a logarithmic scale in FIG. When the inclination of the reflection profile near the regular reflection angle is steep, that is, when the value of R (35) / R (30) is less than 0.4, the reflection of the light source is abruptly reflected near the regular reflection angle. As a result, the reflected image is reflected and the antiglare property is lowered. Focusing only on the anti-reflection effect, it is preferable that the inclination in the vicinity of the regular reflection angle is approximately 0, that is, the value of R (35) / R (30) is approximately 1, but R (35). When the value of / R (30) exceeds 0.8, whitening is likely to occur. Therefore, this value is preferably set to 0.8 or less.

  In the example of the reflection profile shown in FIG. 2, the regular reflectance R (30) is about 0.074%, R (40) is about 0.013%, and R (50) is about 0.0004%. . The value of R (35) / R (30) is about 0.6.

  According to the present inventors' investigation, most of the antiglare films currently on the market are of a type in which filler is dispersed, and in such a type, the regular reflectance R (30) is 0. 04% or more and 0.2% or less, reflectance R (40) at a reflection angle of 40 ° is 0.005% or more and 0.02% or less, and reflectance R (50) at a reflection angle of 50 ° is 0.0015% or less. Moreover, there was no film having a value of R (35) / R (30) of 0.4 or more and 0.8 or less, and as a result, there was no antiglare film having sufficient antiglare performance and low haze. On the other hand, it has been found that the antiglare film defined in the present invention has a low haze and a function of suppressing whitening and glare while exhibiting sufficient antiglare performance.

  In measuring the reflectance of the antiglare film, it is necessary to accurately measure the reflectance of 0.001% or less. Therefore, it is effective to use a detector with a wide dynamic range. As such a detector, for example, a commercially available optical power meter can be used, and an aperture is provided in front of the detector of the optical power meter so that the angle at which the antiglare film is viewed is 2 °. Measurements can be made using an angle photometer. As incident light, visible light of 380 to 780 nm can be used, and as a measurement light source, collimated light emitted from a light source such as a halogen lamp may be used, or a monochromatic light source such as a laser is used in parallel. A high degree may be used. In the case of an antiglare film having a smooth and transparent back surface, reflection from the back surface of the antiglare film may affect the measured value. For example, the smooth surface of the antiglare film is adhered to a black acrylic resin plate with an adhesive or It is preferable that only the reflectance on the outermost surface of the antiglare film can be measured by optical adhesion using a liquid such as water or glycerin.

  The antiglare film of the present invention has a regular reflectance R (30) of 0.04% to 0.2%, R (40) of 0.005% to 0.02%, and R (50 ) Is 0.0015% or less, and can be achieved by satisfying at least one of the shape factors shown in the above (2) to (7).

  First, the requirement that the arithmetic average height Pa in an arbitrary cross-sectional curve of the film uneven surface of (2) is 0.09 μm or more and 0.21 μm or less, and the maximum cross-sectional height Pt in the same arbitrary cross-sectional curve of (3) The requirement that it is 0.5 μm or more and 1.2 μm or less and the requirement that the average length PSm in the same arbitrary sectional curve in (4) is 12 μm or more and 20 μm or less will be described. These arithmetic average height Pa, maximum section height Pt, and average length PSm are defined in JIS B 0601 (= ISO 4287), and arithmetic average height Pa is called centerline average roughness. It is the same as the previous value.

  When the arithmetic average height Pa in the cross-sectional curve of the uneven surface is less than 0.09 μm, the antiglare film surface becomes almost flat and does not exhibit sufficient antiglare performance, which is not preferable. Further, when the arithmetic average height Pa is larger than 0.21 μm, the surface shape becomes rough, and problems such as whitening and glare occur, which is also not preferable. When the maximum cross-sectional height Pt in the cross-sectional curve of the uneven surface is less than 0.5 μm, the anti-glare film surface is still almost flat and does not exhibit sufficient anti-glare performance, which is not preferable. On the other hand, when the maximum cross-sectional height Pt is larger than 1.2 μm, the surface shape becomes too rough and problems such as whitening and glare occur, which is not preferable. When the average length PSm in the cross-sectional curve of the uneven surface is less than 12 μm, the surface shape becomes rough and problems such as whitening and glare occur, which is not preferable. On the other hand, when the average length PSm is larger than 20 μm, the surface of the antiglare film becomes substantially flat and does not exhibit sufficient antiglare performance, which is not preferable.

  The arithmetic average height Pa, average length PSm, and maximum cross-sectional height Pt in the cross-sectional curve of the uneven surface can be measured using a commercially available general contact surface roughness meter in accordance with JIS B 0601. . It is also possible to measure the surface shape with an apparatus such as a confocal microscope, an interference microscope, or an atomic force microscope (AFM), and obtain the value by calculation from the three-dimensional information of the surface shape. In addition, when calculating from three-dimensional information, in order to ensure sufficient reference length, it is preferable to measure three or more areas of 200 μm × 200 μm or more and use the average value as a measurement value.

  Next, when the altitude of each point on the film uneven surface of (5) is represented by a histogram, the peak of the histogram is an intermediate point (high) between the highest point (height 100%) and the lowest point (height 0%). The requirement of being within a range of ± 10% centering on 50%) will be described. This requirement means that the peak of the histogram is in the range of 40% to 60% relative to the difference between the highest and lowest points (maximum elevation). If there is no peak within ± 10% from the midpoint, in other words, if the peak appears at a position greater than 60% or less than 40% relative to the maximum elevation, the surface shape will be rough as a result. Since glare is likely to occur, it is not preferable. In addition, the texture of the appearance tends to be reduced.

  In determining the elevation histogram, the surface shape is measured with a confocal microscope, interference microscope, atomic force microscope (AFM), etc., and the three-dimensional coordinate values of each point on the surface of the antiglare film are obtained. It is determined by the algorithm shown below. That is, after obtaining the highest and lowest elevations on the antiglare film surface, the difference between the elevation of the measurement point and the lowest point (the height of that point) is the difference between the highest and lowest points (maximum elevation). ) To obtain the relative height of each point. The peak position of the histogram is obtained by expressing the obtained relative height as a histogram with the highest point being 100% and the lowest point being 0%. The histogram needs to be divided so that the peak position is not affected by the data error, and is preferably divided into about 10 to 30 for display. In measurement, in order to reduce an error, it is preferable to measure three or more regions of 200 μm × 200 μm or more and use the average value as a measured value.

  FIG. 3 shows an example of an elevation histogram. In this figure, the horizontal axis represents the ratio (unit%) of the height of the measurement point to the difference (maximum elevation) between the above-mentioned highest and lowest points, and is divided in increments of 5%. . For example, the leftmost vertical bar indicates the distribution of a set whose height ratio is in the range of 0 to 5%, and the ratio of height increases by 5% as it goes to the right. In the figure, a scale is displayed every three divisions on the horizontal axis. The vertical axis represents the height distribution and is a value that becomes 1 when integrated. In this example, the peak position appears at a position of 45% to 50% with respect to the maximum altitude. 11, 13, 15, 17, and 19, which show histograms of examples and comparative examples described later, are displayed in the same manner as in FIG. 3.

  Next, the requirement of having 150 to 350 convex portions in the 200 μm × 200 μm region of (6) will be described. If the number of convex portions on the concave / convex surface is small, glare due to interference with pixels occurs and the image becomes difficult to see when used in combination with a high-definition image display device. Moreover, when the number of convex parts increases too much, as a result, the inclination angle of the surface irregularity shape becomes steep, and whitening tends to occur.

  In determining the number of protrusions on the concavo-convex surface of the antiglare film, the surface shape is measured with an apparatus such as a confocal microscope, an interference microscope, an atomic force microscope (AFM), etc. After obtaining a coordinate value, a convex portion is determined by the following algorithm, and the number of the convex portions is counted. That is, when an arbitrary point on the surface of the antiglare film is focused on, there is no point higher than the focused point around that point, and the altitude on the uneven surface of that point is the highest of the uneven surface. When the altitude of the point is higher than the middle of the lowest point, the point is assumed to be the vertex of the convex portion, and the number of convex vertices thus obtained is counted to obtain the number of convex portions. More specifically, as shown in FIG. 4, paying attention to an arbitrary point 21 on the surface of the antiglare film, a circle having a radius of 2 μm to 5 μm parallel to the reference surface 23 of the antiglare film is drawn around the point 21. The point on the antiglare film surface 22 included in the projection surface 24 of the circle does not have a point higher than the point 21 of interest, and the height of the uneven surface of the point is When the altitude is higher than the midpoint between the highest point and the lowest point, the point 21 is determined to be the apex of the convex portion, and the number of convex portions is obtained. At this time, the radius of the circle 24 is required to be a size that does not count fine irregularities on the sample surface and does not include a plurality of convex portions, and is preferably about 3 μm. At the time of measurement, in order to reduce errors, it is preferable to measure three or more areas of 200 μm × 200 μm and use the average value as a measured value.

  In the case of using a confocal microscope, it is preferable that the objective lens has a magnification of about 50 times and is measured with a reduced resolution. This is because if the measurement is performed at a high resolution, fine irregularities on the surface of the sample are measured, and the counting of the convex portions is hindered. Note that when the objective lens is set to a low magnification, the resolution in the height direction is also reduced, so that the surface shape may be difficult to measure in the case of a sample with few irregularities. In such a case, after measuring with a high-magnification objective lens, a low-pass filter is applied to the obtained data to remove high spatial frequency components so that the fine roughness observed on the uneven surface cannot be seen. Then, the number of convex portions may be counted.

Finally, the requirement that the average area of the polygon formed when the surface is voronoi-divided with the vertex of the convex part of the film surface unevenness in (7) as the base point is 100 μm ² or more and 300 μm ² or less will be described. First, the Voronoi division will be explained. When several points (called mother points) are arranged on a plane, the plane can be divided depending on which mother point is closest to any point in the plane. The figure is called Voronoi diagram, and the division is called Voronoi division. FIG. 5 shows an example in which the vertex of the convex portion on the surface of the antiglare film is used as a base point, and the surface is Voronoi divided. Square points 26 and 26 are base points, and each of the multiple points including one base point is shown in FIG. The squares 27 and 27 are regions formed by Voronoi division, which are called Voronoi regions or Voronoi polygons, but are hereinafter called Voronoi polygons. In this figure, the peripherally thinned portions 28, 28 will be described later. In the Voronoi diagram, the number of generating points coincides with the number of Voronoi regions.

When the average area of the Voronoi polygon formed when the Voronoi is divided with the vertex of the convex portion as the base point is less than 100 μm ² , the inclination angle of the antiglare film surface becomes steep, resulting in whitening Since it becomes easy to do, it is not preferable. Further, when the average area of the Voronoi polygon is larger than 300 μm ² , the uneven surface shape becomes rough and glare is likely to occur, which is not preferable.

  Equipment such as confocal microscope, interference microscope, atomic force microscope (AFM) is used to determine the average area of Voronoi polygons obtained by performing Voronoi division using the top of the convex part of the antiglare film as a generating point. After measuring the surface shape and obtaining the three-dimensional coordinate value of each point on the surface of the antiglare film, Voronoi division is performed by the following algorithm to obtain the average area of the Voronoi polygon. That is, according to the algorithm described above with reference to FIG. 4, first, the vertex of the convex portion on the surface of the antiglare film is obtained, and then the vertex of the convex portion is projected onto the reference surface of the antiglare film. After that, all the three-dimensional coordinates obtained by measuring the surface shape are projected onto the reference plane, and all the projected points are assigned to the nearest base point to perform Voronoi division and obtained by division. By determining the area of the polygon, the average area of the Voronoi polygon is determined. In the measurement, in order to reduce the error, the Voronoi polygons that contact the boundary of the measurement field are counted as the number of the convex portions, but are not included when obtaining the average area. Moreover, in order to reduce a measurement error, it is preferable to measure three or more areas of 200 μm × 200 μm or more and use the average value as a measured value.

  As described above in part, FIG. 5 is a Voronoi diagram showing an example when Voronoi division is performed with the convex vertex of the antiglare film as a base point. A large number of generating points 26 and 26 are the vertices of the convex portions of the antiglare film, and one Voronoi polygon 27 is assigned to one generating point 26 by Voronoi division. In this figure, the Voronoi polygons 28 and 28 that are in contact with the boundary of the visual field and are thinly painted are not counted in the calculation of the average area as described above. In this figure, only some of the generating points and Voronoi polygons are provided with leading lines and symbols. However, the fact that there are a large number of generating points and Voronoi polygons is explained above and this figure. Will be easily understood.

  Now, the anti-glare film of the present invention preferably has a haze of 3% or more and 20% or less with respect to normal incident light. When the haze is high, the front contrast when the antiglare film is applied to a liquid crystal panel is lowered, so that the haze is preferably 20% or less. On the other hand, when the haze is less than 3%, the antiglare property is insufficient and the visibility tends to be lowered. The haze of the antiglare film can be measured according to the method shown in JIS K 7136.

  Further, the antiglare film of the present invention has a reflection sharpness measured at a light incident angle of 45 ° using three types of optical combs in which the width of the dark part and the bright part is 0.5 mm, 1.0 mm and 2.0 mm. Is preferably 30% or less. Reflection sharpness is measured by the method specified in JIS K 7105. In this standard, the ratio of the width of the dark part to the bright part is 1: 1 and the width is 0.125 mm, 0.5 mm, 1.0 mm, and 2.0 mm as an optical comb used for measuring the image definition. The type is specified. Among these, when an optical comb with a width of 0.125 mm is used, the measurement error when using an optical comb with a width of 0.125 mm is large because an error in the measured value becomes large in the antiglare film defined in the present invention. The value is not added to the sum, and the sum of image sharpness measured using three types of optical combs having widths of 0.5 mm, 1.0 mm, and 2.0 mm is referred to as reflection sharpness. In this definition, the maximum value of the reflection definition is 300%. When the definition of reflection definition exceeds 30%, an image of a light source or the like is clearly reflected, which is not preferable because of poor antiglare property.

  However, when the reflection definition is 30% or less, it is difficult to compare the superiority and inferiority of the antiglare property only from the reflection definition. This is because if the reflection definition according to the above definition is 30% or less, the reflection definition using optical combs with widths of 0.5 mm, 1.0 mm, and 2.0 mm is only about 10%, resulting in measurement errors. This is because the fluctuation of the reflection definition due to the above cannot be ignored. Therefore, the present inventors visually compared the antiglare film with respect to the antiglare film having a reflection definition of 30% or less obtained by a production method as described later. By comparing and examining the evaluation result of the antiglare property by visual observation and the reflection profile described above, an index that can suitably evaluate the antiglare performance of the antiglare film was found.

  In the antiglare film of the present invention, it is preferable that the pixel density of a high-definition image display element used in combination does not glare up to 100 ppi (pixel per inch). When glare is visible at a pixel density lower than this, it is difficult to use in combination with a high-definition image display element, which is not preferable.

  Glare can be evaluated by the following method. First, a photomask having a unit cell pattern as shown in a plan view in FIG. 6 is prepared. In this figure, the unit cell 30 has a key-shaped chrome light-shielding pattern 31 with a line width of 10 μm formed on a transparent substrate, and a portion where the chrome light-shielding pattern 31 is not formed is an opening 32. In the examples to be described later, a unit cell having a size of 254 μm × 84 μm (vertical × horizontal in the figure), and thus an opening having a dimension of 244 μm × 74 μm (vertical × horizontal in the figure) was used. A large number of unit cells shown in the figure are arranged vertically and horizontally to form a photomask.

  Then, as shown in a schematic cross-sectional view in FIG. 7, a sample in which the chrome light-shielding pattern 31 of the photomask 33 is placed in the light box 35 and the antiglare film 11 is bonded to the glass plate 37 with an adhesive. Place on photomask 33. A light source 36 is disposed in the light box 35. In this state, the sensory evaluation of glare is performed by visually observing from a position 39 about 30 cm away from the sample.

  Next, a method for suitably producing the antiglare film according to the present invention and a method for producing a metal mold having irregularities formed on the surface for obtaining the antiglare film will be described. The antiglare film of the present invention uses a metal mold with irregularities formed in a predetermined shape, transfers the irregular surface of the mold to a transparent resin film, and then transfers the transparent resin film with the irregular surface transferred from the mold. It is advantageously manufactured by the peeling method. In this method, in order to obtain a metal mold having irregularities, copper plating or nickel plating is applied to the surface of the metal substrate, and after polishing the plated surface, fine particles are applied to the polished surface to form irregularities. After performing the process of dulling the uneven shape, the uneven surface is subjected to chrome plating to obtain a mold.

  First, the surface of the metal substrate on which the fine particles are hit to form irregularities and further the chrome plating layer is formed is subjected to copper plating or nickel plating. Thus, by performing copper plating or nickel plating on the surface of the metal constituting the mold, it is possible to improve the adhesion and gloss of chrome plating in the subsequent process. When chrome plating is applied to the surface of iron, etc., or when chrome plating is applied again after forming irregularities on the chrome plating surface by the sandblasting method or the bead shot method, as described in the background section above. The surface tends to be rough, and fine cracks are generated, which may adversely affect the shape of the antiglare film. On the other hand, it has been found that such inconvenience is eliminated by applying copper plating or nickel plating to the surface. This is because copper plating and nickel plating have a high covering property and a strong smoothing action, so that a flat and glossy surface is formed by filling minute irregularities and nests of the metal substrate. These copper plating and nickel plating characteristics eliminate the rough surface of the chromium plating that appears to be due to minute irregularities and nests that existed on the metal substrate, and the high coverage of copper plating and nickel plating. Therefore, it is considered that the occurrence of fine cracks is reduced.

  Copper or nickel as used herein may be a pure metal of each, or may be an alloy mainly composed of copper or an alloy mainly composed of nickel. Therefore, the term “copper” as used herein means to include copper and a copper alloy, and nickel means to include nickel and a nickel alloy. Copper plating and nickel plating may be performed by electrolytic plating or electroless plating, respectively, but electrolytic plating is usually employed.

  Examples of suitable metals for forming the mold include aluminum and iron from the viewpoint of cost. Furthermore, lightweight aluminum is more preferable from the convenience of handling. The aluminum and iron here may be pure metals, respectively, or may be an alloy mainly composed of aluminum or iron. After copper plating or nickel plating is applied to the surface of such a metal substrate, and the surface is further polished to obtain a smoother and more glossy surface, fine irregularities are formed by hitting the surface with fine particles. After performing the process of blunting the uneven shape, chrome plating is further applied thereto to form a mold.

  When copper plating or nickel plating is performed, if the plating layer is too thin, the influence of the base metal cannot be completely eliminated. Therefore, the thickness is preferably 10 μm or more. The upper limit of the plating layer thickness is not critical, but generally about 500 μm is sufficient from the viewpoint of cost and the like.

  The shape of the metal mold may be a flat metal plate or a columnar or cylindrical metal roll. If a metal mold | die is produced using a metal roll, an anti-glare film can be manufactured in a continuous roll shape.

  FIG. 8 is a cross-sectional view schematically showing a process until a metal mold is obtained, taking a case where a flat plate is used as an example. FIG. 8A shows a cross section of the substrate after copper plating or nickel plating and mirror polishing, and a plating layer 42 is formed on the surface of the substrate 41, and the surface is a polished surface 43. It has become. Concavities and convexities are formed by hitting fine particles against the surface of the plated layer 42 after such mirror polishing. FIG. 8B is a schematic cross-sectional view of the substrate 41 after hitting the fine particles. The fine concave surface 44 having a partial spherical shape is formed by hitting the fine particles. FIG. 8C is a schematic cross-sectional view of the substrate 41 after the surface on which the unevenness due to the fine particles is formed is subjected to the process of dulling the uneven shape, and FIG. 8C1 is a state in which the surface is blunted by the etching process. And (C2) show the state of being dulled by copper plating. In (C1), the state of the partially spherical concave surface corresponding to (B) before being blunted by etching is indicated by a broken line. In the example employing the etching process of (C1), the concave surface 44 and the acute protrusion shown in (B) are etched away to form a shape 46a in which the acute protrusion on the partial spherical surface is blunted. ing. On the other hand, in the example adopting the copper plating of (C2), the copper plating layer 45 is formed on the concave surface 44 shown in (B), and thereby the shape 46b in which the acute protrusion on the partial spherical surface is blunted is formed. Is formed.

  Then, the uneven | corrugated shape of the surface is further blunted by giving chromium plating. (D) in FIG. 8 is a schematic cross-sectional view after the chrome plating, and (D1) is a chrome plating on the uneven surface 46a blunted by the etching shown in (C1). (D2) is obtained by applying chromium plating to the copper plating layer 45 shown in (C2). In the example employing the etching process from (C1) to (D1), the chrome plating layer 47 is formed on the surface 46a that has been blunted by the etching shown in (C1), and the surface 48 is Compared to the concave / convex surface 46a of (C1), the concave / convex shape is further relaxed by chrome plating, in other words, the concave / convex shape is relaxed. Moreover, in the example which employ | adopts the copper plating from (C2) to (D2), the copper plating layer 45 is formed on the fine concave surface formed in the copper or nickel plating layer 42 on the board | substrate 41, and also on it. A chrome plating layer 47 is formed on the surface 48, and the surface 48 is duller than the concavo-convex surface 46b of (C2) by chrome plating, in other words, the concavo-convex shape is relaxed. In this way, after the bumps are formed on the surface of the copper or nickel plating layer 42 to form irregularities, the surface 46 (46a or 46b) subjected to the process of dulling the irregularities is subjected to chromium plating, thereby substantially Thus, a metal mold having no flat portion can be obtained. In addition, such a mold is suitable for obtaining an antiglare film exhibiting preferable optical characteristics.

  The plating layer made of copper or nickel on the substrate is hit with fine particles in a state where the surface is polished, but it is particularly preferable that the plating layer is polished close to a mirror surface. This is because the metal plate or metal roll as the base material is often subjected to machining such as cutting or grinding in order to obtain the desired accuracy, and as a result, the processing surface remains on the base material surface. It is. Even in the state where copper plating or nickel plating is applied, those processed marks may remain, and the surface may not be completely smooth in the plated state. In the state where deep processed eyes remain, even if the surface of the substrate is deformed by hitting the fine particles, the unevenness such as the processed eyes may be deeper than the unevenness formed by the fine particles, and the effects of the processed eyes remain. there is a possibility. When an antiglare film is produced using such a mold, the optical properties may be unexpectedly affected.

  There is no particular limitation on the method of polishing the surface of the substrate on which plating has been performed, and any of mechanical polishing, electrolytic polishing, and chemical polishing can be used. Examples of the mechanical polishing method include super finishing, lapping, fluid polishing, and buff polishing. The surface roughness after polishing is represented by a center line average roughness Ra, and Ra is preferably 0.5 μm or less, and more preferably Ra is 0.1 μm or less. If Ra is too large, even if the metal surface is deformed by hitting fine particles, the influence of the surface roughness before deformation may remain, which is not preferable. Also, the lower limit of Ra is not particularly limited, and there is no need to specify it because there is a natural limit from the viewpoint of processing time and processing cost.

  As a method for hitting the surface of the substrate plated with fine particles, an injection processing method is preferably used. Examples of the injection processing method include a sand blast method, a shot blast method, and a liquid honing method. The particles used in these processes are preferably in a shape close to a sphere rather than a shape having sharp corners, and particles of a hard material that are crushed during processing and do not produce sharp corners are preferable. . As particles satisfying these conditions, spherical zirconia beads and alumina beads are preferably used for ceramic particles. For metal particles, beads made of steel or stainless steel are preferred. Furthermore, particles in which ceramic or metal particles are supported on a resin binder may be used.

  By using fine particles having an average particle diameter of 10 to 50 μm, particularly spherical fine particles, as the fine particles that strike the surface of the substrate plated, an anti-glare film exhibiting excellent anti-glare performance can be produced. If the average particle size of the fine particles is smaller than 10 μm, it becomes difficult to form sufficient irregularities on the plated surface, and it becomes difficult to obtain sufficient antiglare performance. On the other hand, if the average particle size of the fine particles is larger than 50 μm, the surface irregularities become rough, and glare is likely to occur or the texture is liable to deteriorate. Here, when processing using fine particles having an average particle size of 15 μm or less, it is preferable to employ a wet blasting method in which the particles are processed by being dispersed in a suitable dispersion medium so that the particles do not aggregate due to static electricity or the like.

Also, the pressure when hitting the fine particles, the amount of fine particles used, the distance from the nozzle that sprays the fine particles to the metal surface also affects the uneven shape after processing, and eventually the surface shape of the antiglare film, The pressure is about 0.1 to 0.4 MPa in gauge pressure, the amount of fine particles is about 4 to 12 g per 1 cm ² of the surface area of the metal to be treated, and the distance from the nozzle for spraying the fine particles to the metal surface is about 200 mm to 600 mm. What is necessary is just to select suitably according to the kind and particle diameter of a microparticle, the kind of metal, the shape of the nozzle which injects a microparticle, a desired uneven | corrugated shape, etc.

  The concavo-convex shape formed by hitting fine particles on the surface of the substrate plated has an arithmetic average height Pa of any cross-sectional curve of 0.1 μm or more and 1 μm or less, and the arithmetic average height of the cross-sectional curve The ratio Pa / PSm between Pa and the average length PSm is preferably 0.02 or more and 0.1 or less. When the arithmetic average height Pa is less than 0.1 μm or the ratio Pa / PSm is less than 0.02, the uneven surface is substantially flat when the uneven shape is blunted before the chrome plating process. It becomes difficult to obtain a mold having the desired surface shape. In addition, when the arithmetic average height Pa is greater than 1 μm or the ratio Pa / PSm is greater than 0.1, the process of dulling the concavo-convex shape before chrome plating must be performed under strong conditions. It tends to be difficult to control the shape.

  Thus, the process which blunts an uneven | corrugated shape is given to the base material with which the unevenness | corrugation was formed in the copper plating or nickel plating surface. As the process for dulling the uneven shape, as described above with reference to FIGS. 8C and 8D, etching treatment or copper plating is preferable. By performing the etching process, the sharp portion of the uneven shape produced by hitting the fine particles is eliminated. Thereby, the optical characteristic of the anti-glare film produced when it uses as a metal mold | die changes in a preferable direction. Moreover, since the copper plating has a strong smoothing action, the effect of dulling the uneven shape is stronger than that of the chromium plating. Thereby, the optical characteristic of the anti-glare film produced when it uses as a metal mold | die changes in a preferable direction.

Etching is usually performed by corroding the surface using an aqueous ferric chloride (FeCl ₃ ) solution, an aqueous cupric chloride (CuCl ₂ ) solution, an alkaline etchant (Cu (NH ₃ ) ₄ Cl ₂ ), or the like. However, a strong acid such as hydrochloric acid or sulfuric acid can be used, or reverse electrolytic etching by applying a potential opposite to that during electrolytic plating can be used. The degree of unevenness after etching is different depending on the type of underlying metal and the size and depth of the unevenness obtained by blasting techniques. The largest factor is the etching amount. The etching amount here is the thickness of the base material (plating layer) to be cut by etching. If the etching amount is small, the effect of dulling the surface shape of the unevenness obtained by a technique such as blasting is insufficient, and the optical characteristics of the antiglare film obtained by transferring the uneven shape to a transparent film are not so good. . On the other hand, when the etching amount is too large, the uneven shape is almost lost and the die is almost flat, so that the antiglare property is not exhibited. Therefore, the etching amount is preferably 1 μm or more and 20 μm or less, and more preferably 2 μm or more and 10 μm or less.

  When copper plating is used as the dulling process, the unevenness of the unevenness varies depending on the type of base metal, the size and depth of the unevenness obtained by techniques such as blasting, and the type and thickness of the plating. Although it cannot be said, the greatest factor in controlling the degree of rounding is the plating thickness. If the thickness of the copper plating layer is thin, the effect of dulling the surface shape of the unevenness obtained by techniques such as blasting is insufficient, and the optical properties of the antiglare film obtained by transferring the uneven shape to a transparent film are insufficient. It doesn't get much better. On the other hand, when the plating thickness is too thick, the productivity is deteriorated and the uneven shape is almost lost, so that the antiglare property is not exhibited. Therefore, the thickness of the copper plating is preferably 1 μm or more and 20 μm or less, and more preferably 4 μm or more and 10 μm or less.

  In this way, after dulling the surface shape of the substrate on which the unevenness is formed on the copper plating or nickel plating surface, the surface of the unevenness is further dulled and further the surface hardness is increased by applying chrome plating. Make a metal plate. The degree of unevenness at this time also differs depending on the type of base metal, the size and depth of the unevenness obtained by techniques such as blasting, and the type and thickness of the plating. The greatest factor in controlling is the plating thickness. If the thickness of the chrome plating layer is thin, the effect of dulling the surface shape of the unevenness obtained before the chrome plating process is insufficient, and the optical characteristics of the antiglare film obtained by transferring the uneven shape to a transparent film are It doesn't get much better. On the other hand, when the plating thickness is too thick, productivity is deteriorated and a protruding plating defect called a nodule is generated. Therefore, the thickness of the chrome plating is preferably 1 μm or more and 10 μm or less, and more preferably 2 μm or more and 6 μm or less.

In the present invention, a chrome plating that has a glossy surface, a high hardness, a low friction coefficient, and good releasability is employed on the surface of a flat plate or a roll. The type of chrome plating is not particularly limited, but it is preferable to use a chrome plating that expresses a good gloss, so-called gloss chrome plating or decorative chrome plating. Chromium plating is usually performed by electrolysis, and an aqueous solution containing chromic anhydride (CrO ₃ ) and a small amount of sulfuric acid is used as the plating bath. By adjusting the current density and electrolysis time, the thickness of the chromium plating can be controlled.

  The surface of the mold on which chromium plating is applied preferably has a Vickers hardness of 800 or more, more preferably 1000 or more. If the Vickers hardness is low, the durability when using the mold is reduced, and the decrease in hardness due to chrome plating is likely to cause abnormalities in the plating bath composition and electrolytic conditions during the plating process. There is a high possibility that the occurrence of defects will also have an undesirable effect.

  Patent Document 1, Patent Document 4, Patent Document 6 and the like listed in the Background Art section disclose the use of chrome plating, but depending on the type of the base and the chrome plating before the metal plating, In many cases, the surface is roughened after plating or a lot of minute cracks are generated by chrome plating, and as a result, the optical characteristics of the produced antiglare film proceed in an unfavorable direction. Those having a rough plated surface are not suitable for metal molds for anti-glare films. This is because the plating surface is generally polished after chrome plating in order to eliminate roughness, but as described later, polishing of the surface after plating is not preferable in the present invention. In the present invention, such inconvenience that is likely to occur in chromium plating is eliminated by applying copper plating or nickel plating to the base metal.

  In the case where the process of dulling the concavo-convex shape is not performed before the chrome plating, the chrome plating must be thickened in order to sufficiently dull the sharp portion of the concavo-convex shape produced by hitting fine particles. However, if the thickness of the chrome plating is too thick, nodules are likely to be generated, which is not preferable. In addition, when the thickness of the chrome plating is reduced, the uneven shape produced by hitting the fine particles cannot be sufficiently dulled, and a mold having the desired surface shape cannot be obtained. The produced anti-glare film does not exhibit excellent anti-glare performance.

  Patent Document 1 describes that a chrome-plated roller is formed on a surface of iron by forming a concavo-convex surface by a sandblasting method or a bead shot method, and Patent Document 2 describes that a metal surface is etched or etched. It is described that irregularities are formed by a technique such as sand blasting, and Patent Document 5 and Patent Document 6 describe that a bead shot method or a blasting process is performed on the roll surface. However, like the method shown in the present invention, after forming a concavo-convex shape by hitting fine particles, the surface shape is actively blunted, and then a chrome plating process is performed to dull the surface concavo-convex shape According to the study by the present inventors, an anti-glare film exhibiting excellent anti-glare performance unless the surface shape is actively dulled as in the method shown in the present invention. Could not be manufactured.

  In addition, it is not preferable to apply plating other than chromium plating to the metal surface with unevenness. This is because plating other than chromium has low hardness and wear resistance, so that the durability as a mold is lowered, and unevenness is worn away during use or the mold is damaged. In an antiglare film obtained from such a mold, there is a high possibility that a sufficient antiglare function cannot be obtained, and there is a high possibility that defects will occur on the film.

  Polishing the surface after plating as disclosed in Patent Document 6 is also not preferable in the present invention. By polishing, a flat portion is generated on the outermost surface, which may cause deterioration of optical characteristics, and because shape control factors increase, it becomes difficult to control the shape with good reproducibility. It is. FIG. 9 shows a process of dulling the uneven shape obtained by hitting fine particles, here, the surface subjected to the chrome plating shown in (D1) after performing the etching process shown in (C1) of FIG. It is a cross-sectional schematic diagram of the metal plate in which the flat surface was produced when the surface was polished. By polishing, some of the surface irregularities 48 of the chrome plating layer 47 formed on the surface of the copper or nickel plating layer 42 are shaved, resulting in a flat surface 49. FIG. 9 shows an example in which the post-etching chrome-plated surface shown in FIG. 8D1 is polished, but also in the case of chrome-plating after copper plating shown in FIG. If the surface is polished, a flat surface is similarly generated.

  Next, the process of manufacturing an anti-glare film using the metal mold obtained in this way will be described. An antiglare film is obtained by transferring the shape of the metal mold obtained by the method described above to a transparent resin film. The transfer to the mold-shaped film is preferably performed by embossing. Examples of embossing include a UV embossing method using a photocurable resin and a hot embossing method using a thermoplastic resin.

  In the UV embossing method, a photocurable resin layer is formed on the surface of a transparent substrate film, and the photocurable resin layer is cured while pressing the photocurable resin layer against the metal surface. Transferred to the resin layer. Specifically, an ultraviolet curable resin is applied on a transparent base film, and the applied ultraviolet curable resin is in close contact with a metal mold, and ultraviolet rays are irradiated from the transparent base film side. The shape of the metal mold is transferred to the ultraviolet curable resin by curing the ultraviolet curable resin and then peeling the transparent substrate film on which the cured ultraviolet curable resin layer is formed from the metal mold. The kind of ultraviolet curable resin is not particularly limited. Moreover, although expressed as an ultraviolet curable resin, a resin that can be cured even by visible light having a wavelength longer than that of ultraviolet rays can be obtained by appropriately selecting a photoinitiator. That is, the term “ultraviolet curable resin” as used herein is a generic name including such a visible light curable resin. On the other hand, in the hot embossing method, a transparent thermoplastic resin film is pressed against a metal mold in a heated state, and the surface shape of the mold is transferred to the thermoplastic resin film. Among these embossing methods, the UV embossing method is preferable from the viewpoint of productivity.

  The transparent substrate film that can be used for the production of the antiglare film may be substantially optically transparent, and examples thereof include resin films such as a triacetyl cellulose film and a polyethylene terephthalate film.

  A commercially available product can be used as the ultraviolet curable resin. For example, polyfunctional acrylates such as trimethylolpropane triacrylate and pentaerythritol tetraacrylate are used alone or in admixture of two or more thereof, and “Irgacure 907”, “Irgacure 184” (above, Ciba A product obtained by mixing a photopolymerization initiator such as “Specialty Chemicals” or “Lucirin TPO” (BASF) can be used as an ultraviolet curable resin.

  The thermoplastic transparent resin film used in the hot embossing method may be any film as long as it is substantially transparent. For example, polymethyl methacrylate, polycarbonate, polyethylene terephthalate, triacetyl cellulose, norbornene compounds A solvent cast film or an extruded film of a thermoplastic resin such as amorphous cyclic polyolefin as a monomer can be used. These transparent resin films can also be transparent substrate films when the UV embossing method described above is employed.

  The antiglare film of the present invention configured as described above has an excellent antiglare effect and effectively prevents whitening, and therefore has excellent visibility when mounted on an image display device. When the image display device is a liquid crystal display, this antiglare film can be laminated on a polarizing film. That is, in general, a polarizing film is often in a form in which a protective film is laminated on at least one surface of a polarizer made of a polyvinyl alcohol-based resin film on which iodine or a dichroic dye is adsorbed and oriented. If an antiglare film with the above irregularities is bonded to one surface, an antiglare polarizing film is obtained. In addition, the above-described anti-glare uneven film is used as a protective film and anti-glare layer, and the anti-glare layer is bonded to one side of the polarizer so that the uneven surface is on the outside. It can be set as a polarizing film. Furthermore, in the polarizing film in which the protective film is laminated, the antiglare polarizing film can be obtained by providing the antiglare unevenness as described above on the surface of the single-sided protective film.

  The image display device of the present invention is a combination of an antiglare film having a specific surface shape as described above and an image display means. Here, the image display means is typically a liquid crystal panel that includes a liquid crystal cell in which liquid crystal is sealed between upper and lower substrates and displays an image by changing the alignment state of the liquid crystal by applying a voltage. The antiglare film of the present invention can also be applied to various known displays such as panels, CRT displays, and organic EL displays. And an image display apparatus is comprised by arrange | positioning an above-described anti-glare film to the visual recognition side rather than an image display means. Under the present circumstances, it arrange | positions so that the uneven surface of an anti-glare film may become an outer side (viewing side). The antiglare film may be directly bonded to the surface of the image display means. When the liquid crystal panel is used as the image display means, for example, as described above, the antiglare film is bonded to the surface of the liquid crystal panel via the polarizing film. You can also Thus, the image display device provided with the antiglare film of the present invention can scatter incident light due to the unevenness of the surface of the antiglare film, blur the reflected image, and give excellent visibility. .

  In addition, even when the antiglare film of the present invention is applied to a high-definition image display device, the glare as seen in the conventional antiglare film does not occur, and although it has low haze, sufficient reflection It has the functions of prevention, prevention of whitishness, and suppression of glare.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. The evaluation method of the metal mold | die or anti-glare film in the following examples is as follows.

1. Measurement of Vickers hardness of mold
Vickers hardness was measured by a method based on JIS Z 2244 using an ultrasonic hardness tester “MIC10” manufactured by Krautkramer. The measurement was performed on the surface of the mold itself.

2. Measurement of optical properties of antiglare film (reflectance)
The uneven surface of the antiglare film is irradiated with parallel light from a He—Ne laser from a direction inclined by 30 ° with respect to the film normal, and the angle change of reflectance in a plane including the film normal and the irradiation direction is changed. Measurements were made. In the measurement of reflectance, both “3292 03 Optical Power Sensor” and “3292 Optical Power Meter” manufactured by Yokogawa Electric Corporation were used.

(Haze)
The haze of the antiglare film was measured using a haze meter “HM-150” manufactured by Murakami Color Research Laboratory Co., Ltd. based on JIS K 7136. In the measurement, in order to prevent the sample from warping, it was bonded to a glass substrate using an optically transparent pressure-sensitive adhesive so that the concavo-convex surface became the surface, and the measurement was performed in that state.

(Transparency definition)
The transmission clarity of the antiglare film was measured using an image clarity measuring device “ICM-1DP” manufactured by Suga Test Instruments Co., Ltd. in accordance with JIS K 7105. Also in this case, in order to prevent the sample from warping, it was subjected to measurement after being bonded to a glass substrate using an optically transparent adhesive so that the concavo-convex surface became the surface. In this state, light was incident from the glass side and measurement was performed. The measured value here is a total value of values measured using four types of optical combs in which the widths of the dark portion and the bright portion are 0.125 mm, 0.5 mm, 1.0 mm, and 2.0 mm, respectively. In this case, the maximum value of the transmission clarity is 400%.

(Reflection sharpness)
The reflection clarity of the antiglare film was measured using the same image clarity measuring device “ICM-1DP” as above. Also in this case, in order to prevent the sample from warping, it was subjected to measurement after being bonded to a glass substrate using an optically transparent adhesive so that the concavo-convex surface became the surface. In addition, in order to prevent reflection from the back glass surface, a 2 mm thick black acrylic resin plate is adhered to the glass surface of the glass plate on which the antiglare film is pasted, and the sample (antiglare film in this state) is attached. ) Side was used for measurement. As described above, the measured value here is a total value of values measured using three types of optical combs in which the widths of the dark part and the bright part are 0.5 mm, 1.0 mm, and 2.0 mm, respectively.

3. Measurement of surface shape of antiglare film
The surface shape of the antiglare film was measured using a confocal microscope “PLμ2300” manufactured by Sensofar. Also in this case, in order to prevent the sample from warping, it was subjected to measurement after being bonded to a glass substrate using an optically transparent adhesive so that the concavo-convex surface became the surface. At the time of measurement, the magnification of the objective lens was 50 times, and the measurement was performed with a reduced resolution. This is because if the measurement is performed at a high resolution, fine irregularities on the surface of the sample are measured, and the counting of the convex portions is hindered.

(Arithmetic mean height Pa, maximum cross section height Pt, and mean length PSm in the section curve)
Based on the measurement data obtained above, the arithmetic average height Pa, the maximum cross-sectional height Pt, and the average length PSm were obtained by calculation based on JIS B 0601.

(Elevation histogram)
Based on the three-dimensional coordinate values of each point on the surface of the antiglare film obtained in the above measurement, 5 points between the highest point (height 100%) and the lowest point (height 0%) according to the algorithm described above. The peak position was obtained by dividing by% increments and creating a histogram.

(Number of convex parts)
Based on the three-dimensional coordinate value of each point on the surface of the antiglare film obtained by the above measurement, according to the algorithm described above with reference to FIG. 4, the convex portions existing in the region of 200 μm × 200 μm I asked for a number.

(Voronoi polygon average area when Voronoi is divided)
Based on the three-dimensional coordinate values of each point on the antiglare film surface obtained in the above measurement, calculation is made based on the algorithm described above with reference to FIG. 5, and the average area of the Voronoi polygon is obtained. It was.

4). Evaluation of anti-glare performance of anti-glare film (visual evaluation of reflection, whitishness and texture)
In order to prevent reflection from the back surface of the antiglare film, the antiglare film is bonded to the black acrylic resin plate so that the uneven surface becomes the surface, and visually observed from the uneven surface side in a bright room with a fluorescent lamp. Then, the presence or absence of reflection of a fluorescent lamp, the degree of whitishness, and the texture were visually evaluated. Reflection, whitishness and texture were evaluated according to the following criteria in three stages of 1 to 3, respectively.

Reflection 1: Reflection is not observed,
2: Reflection is slightly observed,
3: Reflection is clearly observed.

White 1: The white is not observed,
2: A little whitish is observed,
3: The whitish is clearly observed.

Texture 1: Fine eyes, good texture,
2: The eyes are slightly rough and the texture is a little bad.
3: The eyes are clearly rough and the texture is poor.

(Evaluation of glare)
Glare was evaluated by the method described above with reference to FIGS. That is, a photomask having the unit cell pattern shown in FIG. 6 is prepared, and this is placed in the light box 35 with the chrome light-shielding pattern 31 of the photomask 33 facing up, as shown in FIG. A sample in which the antiglare film 21 is bonded to a glass plate 37 with an adhesive having a thickness of 20 μm is placed on a photomask 33, and visually observed from a position 39 that is about 30 cm away from the sample, so that the degree of glare is controlled in seven stages. evaluated. Level 1 corresponds to a state where no glare is recognized, level 7 corresponds to a state where severe glare is observed, and level 3 refers to a state where only slight glare is observed. Note that the unit cell of the photomask has a unit cell length × unit cell width in FIG. 6 of 254 μm × 84 μm, and thus the opening length × opening width in the figure is 244 μm × 74 μm.

[Example 1]
A 200 mm diameter iron roll (JIS STKM13A) with a copper ballad plated surface was prepared. The copper ballad plating consists of a copper plating layer / thin silver plating layer / surface copper plating layer, and the total thickness of the plating layer was about 200 μm. The copper-plated surface is mirror-polished, and blasting equipment (manufactured by Fuji Seisakusho Co., Ltd.) is used on the polished surface. The zirconia beads “TZ-SX-17” (trade name, average) manufactured by Tosoh Corporation Particle size 20 μm), beads are used 8 g / cm ² (the amount used per 1 cm ² of the surface area of the roll, hereinafter referred to as “blast amount”), blast pressure 0.25 MPa (gauge pressure, the same applies hereinafter), fine particles are sprayed Blasting was performed at a distance of 300 mm from the nozzle to the metal surface (hereinafter referred to as “blasting distance”), and the surface was uneven. The obtained copper-plated iron roll with unevenness was etched with an aqueous cupric chloride solution. The etching amount at that time was set to 4 μm. Thereafter, chrome plating was performed to produce a metal mold. At this time, the chromium plating thickness was set to 4 μm. The obtained mold had a surface Vickers hardness of 1,000.

Separately, a photocurable resin composition “GRANDIC 806T” (trade name) manufactured by Dainippon Ink & Chemicals, Inc. is dissolved in ethyl acetate to obtain a 50% strength by weight solution, which is a photopolymerization initiator. “Lucirin TPO” (manufactured by BASF, chemical name: 2,4,6-trimethylbenzoyldiphenylphosphine oxide) was added at 5 parts by weight per 100 parts by weight of the curable resin component to prepare a coating solution. This coating solution was applied onto a triacetylcellulose (TAC) film having a thickness of 80 μm so that the coating thickness after drying was 5 μm, and dried in a drier set at 60 ° C. for 3 minutes. The dried film was brought into close contact with the uneven surface of the metal mold produced above with a rubber roll so that the photocurable resin composition layer was on the mold side. In this state, light from a high-pressure mercury lamp having an intensity of 20 mW / cm ² was irradiated from the TAC film side so that the amount of light in terms of h-line was 200 mJ / cm ² to cure the photocurable resin composition layer. Thereafter, the TAC film was peeled from the mold together with the cured resin to obtain a transparent antiglare film comprising a laminate of the cured resin having irregularities on the surface and the TAC film.

  About the obtained anti-glare film, the optical characteristics, the uneven surface shape, and the anti-glare performance were evaluated by the method described above, and the results are shown in Table 1 together with the mold production conditions. Further, FIG. 10 shows a scattering characteristic (reflection profile graph) of reflected light obtained in the reflectance measurement, and FIG. 11 shows an altitude histogram. In addition, the breakdown of the reflection definition and the transmission definition in Table 1 (A) is as follows.

Reflection sharpness Transmission sharpness 0.125 mm Optical comb: −22.7%
0.5mm optical comb: 3.0% 19.7%
1.0mm optical comb: 6.3% 20.8%
2.0mm optical comb: 9.4% 28.6%
Total 18.7% 91.8%

[Examples 2-3 and Comparative Examples 1-2]
The blast pressure at the time of mold production was changed as shown in Table 1, and the others were the same as in Example 1 to produce a metal mold having irregularities on the surface. In any of the examples, the obtained mold had a surface Vickers hardness of 1,000. Using each mold, a transparent antiglare film comprising a laminate of a cured resin having irregularities on the surface and a TAC film was produced in the same manner as in Example 1. The optical properties, surface shape, and antiglare performance of the obtained antiglare film are shown in Table 1 together with the mold production conditions. In Table 1, (A) summarizes the mold preparation conditions and the optical properties of the antiglare film, and (B) summarizes the surface shape and antiglare performance of the antiglare film.

  Moreover, about Example 2 and 3, the reflection profile graph of the anti-glare film was shown in FIG. 10 with the result of Example 1, and the histogram of the altitude was shown in FIG. 11 with the result of Example 1, respectively. For Comparative Examples 1 and 2, a reflection profile graph of the antiglare film is shown in FIG. 12, and an altitude histogram is shown in FIG.

[Example 4]
The roll surface is blasted in the same manner as in Example 1 except that the blast pressure at the time of mold production is changed to 0.3 MPa and the blast distance is changed to 450 mm, and then copper plating is performed as a process for dulling the uneven shape. Adopting and setting the plating thickness at that time to 8 μm, the others were made in the same manner as in Example 1 to produce a metal mold having irregularities on the surface. The obtained mold had a surface Vickers hardness of 1,000. Using the mold, a transparent antiglare film made of a laminate of a cured resin having irregularities on the surface and a TAC film was produced in the same manner as in Example 1. The optical properties, surface shape, and antiglare performance of the obtained antiglare film are shown in Table 1 together with the mold production conditions. In addition, a graph of the reflection profile of the antiglare film is shown in FIG. 12 together with the results of Comparative Examples 1 and 2, and an altitude histogram is shown in FIG. 13 together with the results of Comparative Examples 1 and 2.

  As shown in Table 1, in Comparative Example 1, the regular reflectance R (30) is more than 0.2%, and R (40) is less than 0.005%. Sex was not expressed. In Comparative Example 2, since the regular reflectance R (30) was less than 0.04%, the whitening was severe. Further, Comparative Examples 1 and 2 did not satisfy some of the other requirements defined in the present invention, and as a result, they did not have the performance of low haze while exhibiting sufficient antiglare properties.

  On the other hand, in the samples of Examples 1 to 4 whose reflection profile and surface shape satisfy the provisions of the present invention, reflection is not observed, whiteness is little, glare is hardly observed, and excellent antiglare performance Was shown.

[Comparative Examples 3 and 4]
The fine particles used for blasting are changed to the zirconia beads “TZ-B125” (trade name, average particle size 125 μm) manufactured by Tosoh Corporation, and the blasting amount, blasting pressure, blasting distance, and surface shape are blunted. A metal mold having irregularities on the surface was prepared in the same manner as in Example 1 except that it was as shown in Table 2. All of the obtained molds had a surface Vickers hardness of 1,000. Using each mold, a transparent antiglare film comprising a laminate of a cured resin having irregularities on the surface and a TAC film was produced in the same manner as in Example 1. The optical properties, surface shape and antiglare performance of the obtained antiglare film are shown in Table 2 together with the mold production conditions. In Table 2, (A) summarizes the mold preparation conditions and the optical properties of the antiglare film, and (B) summarizes the surface shape and antiglare performance of the antiglare film. Further, a graph of the reflection profile of the antiglare film is shown in FIG. 14, and an altitude histogram is shown in FIG.

  Comparative Examples 3 and 4 did not satisfy the requirements defined in the present invention, and reflection was observed in Comparative Example 3, and a high level of glare and a decrease in texture were observed in Comparative Example 4. In the blasting process, when fine particles having a large average particle size were used, when the blast pressure was weak or the blasting distance was long, although there was a low haze, there was a tendency that reflection was likely to occur. On the other hand, when the blast pressure is strong or the blast distance is short, it has sufficient anti-reflection performance, but the glare is remarkably high and the texture tends to be poor. In order to obtain an antiglare film having a low haze while exhibiting the excellent antiglare property defined in the present invention, it is necessary to employ appropriate mold preparation conditions.

[Comparative Examples 5 and 6]
The surface of a 300 mm diameter aluminum roll (JIS A5056) was mirror-polished. The same zirconia beads “TZ-SX-17” as used in Example 1 were blasted on the surface of the obtained mirror polished aluminum roll at a blasting amount of 8 g / cm ² , a blasting pressure of 0.1 MPa, and a blasting distance of 450 mm. The surface was uneven. The obtained aluminum roll with unevenness was subjected to electroless bright nickel plating under two conditions to produce a metal mold. The plating thickness was measured using a β-ray film thickness measuring device (trade name “Fischerscope MMS”, obtained from Fisher Instruments Co., Ltd.) after the plating was completed. Using these molds, in the same manner as in Example 1, a transparent antiglare film made of a laminate of a cured resin having irregularities on the surface and a TAC film was produced. The optical characteristics, surface shape and antiglare performance of the obtained antiglare film are shown in Table 3 together with the electroless nickel plating thickness at the time of mold production. In this table, (A) summarizes the mold preparation conditions and the optical characteristics of the antiglare film, and (B) summarizes the surface shape and antiglare performance of the antiglare film. Further, the reflection profile of the antiglare film is shown in FIG. 16, and the altitude histogram is shown in FIG.

  As shown in Table 3, in the samples of Comparative Examples 5 and 6, the regular reflectance R (30) is both higher than 0.2% and R (40) is lower than 0.005%. It did not exhibit sufficient anti-reflection performance. Glare also occurred.

[Comparative Examples 7-12]
Anti-glare films “AG1,” “AG3,” “AG5”, “AG5” are used as an antiglare layer in the polarizing plate “Sumikaran” sold by Sumitomo Chemical Co., Ltd. For AG6 "," AG8 ", and" SL6 "(respectively referred to as Comparative Example 7 to Comparative Example 12), the respective optical characteristics, surface shape, and antiglare performance were evaluated by the above-described methods, and the results are shown in Table 4. It was. In Table 4, (A) summarizes the optical characteristics of the antiglare film, and (B) summarizes the surface shape and antiglare performance of the antiglare film. Further, a reflection profile graph is shown in FIG. 18, and an altitude histogram is shown in FIG. In FIG.18 and FIG.19, (A) is a result of Comparative Examples 7-9, respectively, (B) is a result of Comparative Examples 10-12.

  As shown in Table 4, none of the Comparative Examples 7 to 12 satisfies the requirements defined in the present invention, and as a result, sufficient reflection prevention, low haze, whitening prevention, and glare prevention are all achieved. There was no anti-glare film. The anti-glare films of Comparative Examples 7 and 8 do not exhibit sufficient anti-reflection performance because the regular reflectance R (30) is more than 0.2% and R (40) is less than 0.005%. It was. Also, glare was noticeable. Since the anti-glare films of Comparative Examples 9 and 11 had R (40) of less than 0.005%, the anti-reflection performance was not sufficient. In the antiglare film of Comparative Example 10, R (50) exceeded 0.0015%, and thus whitening occurred. The antiglare film of Comparative Example 12 satisfied the provisions of the present invention in R (30), R (40) and R (50), but did not satisfy the other requirements. It did not have all of prevention of jamming, low haze, whitening prevention, and glare prevention.

  From the above results, it was found that having the requirements defined in the present invention in a well-balanced manner is necessary for achieving the optical characteristics aimed by the present invention.

  By disposing the antiglare film of the present invention on various displays such as a liquid crystal panel, a plasma display panel, a CRT display, and an organic EL display so that the antiglare film is closer to the viewing side than the image display element. It is possible to blur the reflected image without generating a blur and a glare, and to provide excellent visibility.

It is a perspective view which shows typically the incident direction and reflection direction of the light to an anti-glare film. It is an example of the graph which plotted the reflection angle and reflectance (a reflectance is a logarithmic scale) of the reflected light with respect to the light which injected at an angle of 30 degrees from the normal line of an anti-glare film. It is an example which represented the altitude histogram of the anti-glare film on the graph. It is the perspective view which showed typically the algorithm of the convex part determination of an anti-glare film. It is a Voronoi figure which shows an example when performing Voronoi division | segmentation by using the convex-part vertex of an anti-glare film as a base point. It is a top view which shows the unit cell of the pattern for glare evaluation. It is a cross-sectional schematic diagram which shows the state of glare evaluation. It is a cross-sectional schematic diagram which shows the manufacturing method of the metal mold | die for producing the anti-glare film which concerns on this invention for every process. It is a cross-sectional schematic diagram which shows the state which grind | polished the surface after chromium plating. It is a graph showing the reflection profile of the anti-glare film obtained in Examples 1-3. It is a graph showing the histogram of the altitude of the anti-glare film obtained in Examples 1-3. It is a graph showing the reflection profile of the anti-glare film obtained in Comparative Examples 1-2 and Example 4. It is a graph showing the histogram of the altitude of the anti-glare film obtained in Comparative Examples 1-2 and Example 4. It is a graph showing the reflection profile of the anti-glare film obtained in Comparative Examples 3 and 4. It is a graph showing the histogram of the altitude of the anti-glare film obtained in Comparative Examples 3 and 4. It is a graph showing the reflection profile of the anti-glare film obtained in Comparative Examples 5 and 6. It is a graph showing the histogram of the altitude of the anti-glare film obtained in Comparative Examples 5 and 6. It is a graph showing the histogram of an altitude about the anti-glare film of Comparative Examples 7-12. It is a graph showing a reflection profile about the anti-glare film of Comparative Examples 7-12.

Explanation of symbols

11 ... Anti-glare film,
12 ... Film normal,
13: Incident light direction,
15 …… Specular reflection direction,
16 …… Any reflection direction,
18 …… Surface including incident light direction and film normal,
θ …… Reflection angle,
21 …… Any point on the antiglare film,
22 …… Anti-glare film surface,
23 …… Film reference plane,
24 …… A projected circle of a circle centered on an arbitrary point on the antiglare film on the film reference plane,
26 …… Projection point of convex part vertex (voron point of Voronoi division),
27 …… Voronoi polygon,
28 ...... Voronoi polygon that touches the measurement field boundary not counted as an average value,
30 …… Photomask unit cell,
31 …… Photomask chrome shading pattern,
32 …… Photomask opening,
33 …… Photomask,
35 …… Light box,
36 …… Light source,
37 …… Glass plate,
39 …… Glazing observation position,
41 …… Metal substrate,
42 …… Copper or nickel plating layer,
43 …… Polished surface,
44. Concave surface formed by hitting fine particles,
45 …… Copper plating layer,
46a: a surface obtained by etching an uneven surface formed by hitting fine particles,
46b: a surface in which the uneven surface formed by hitting the fine particles is dulled by copper plating,
47 …… Chrome plating layer,
48 .. Uneven surface remaining after chrome plating,
49. Flat surface generated when the surface after chromium plating is polished.

Claims (4)

It is an antiglare film in which fine irregularities are formed on the surface,
For light incident at an incident angle of 30 °, the reflectance R (30) at a reflection angle of 30 ° is 0.04% or more and 0.2% or less, and the reflectance R (40) at a reflection angle of 40 ° is 0.005. The reflectance R (50) at a reflection angle of 50 ° is 0.0015% or less at a reflection angle of 35 ° to 0.02%, and the reflectance in the direction of a reflection angle of 35 ° with respect to light incident at an incidence angle of 30 °. as R (35), R (35 ) / the value of R (30) is Ri der 0.4 to 0.8,
Arithmetic mean height Pa in an arbitrary cross-sectional curve of the film uneven surface is 0.09 μm or more and 0.21 μm or less,
The maximum cross-sectional height Pt in an arbitrary cross-sectional curve of the film uneven surface is 0.5 μm or more and 1.2 μm or less,
The average length PSm in an arbitrary cross-sectional curve of the film uneven surface is 12 μm or more and 20 μm or less,
When the elevation of each point on the uneven film surface is represented by a histogram, the peak of the histogram is centered on the middle point (height 50%) between the highest point (height 100%) and the lowest point (height 0%). Exists within ± 10%,
150 to 350 convex portions in a 200 μm × 200 μm region,
An anti-glare film, wherein an average area of a polygon formed when a surface is Voronoi-divided with a vertex of a convex portion of the film surface unevenness being a base point is 100 μm ² or more and 300 μm ² or less . The anti-glare film according to claim 1, wherein the haze with respect to normal incident light is 3% or more and 20% or less. The sum of reflection sharpness measured at a light incident angle of 45 ° using three types of optical combs having a dark part and a bright part width of 0.5 mm, 1.0 mm and 2.0 mm is 30% or less. Item 3. The antiglare film according to Item 1 or 2 . And the antiglare film according to any one of claims 1 to 3 and an image display device, image display device, characterized in that the antiglare film is disposed on the viewing side of the image display device.