KR20100132447A - Manufacturing method of antiglare film, antiglare film and manufacturing method of mold - Google Patents

Abstract

PURPOSE: A method for manufacturing an antiglare film, the antiglare film, and a method for manufacturing a mold are provided to implement high contrast and prevent glare. CONSTITUTION: The surface(8) of a molding substrate(7) is plated with copper or nickel. The plated surface is polished. A photosensitive resin film(9) is formed on the polished surface. A gradation pattern is exposed. The exposed photosensitive resin film is developed with the gradation pattern. The developed photosensitive resin film is used as a mask and is etched. A polished unevenness is formed on a plated surface. The photosensitive resin film is exfoliated.

Description

Manufacturing method of anti-glare film, manufacturing method of anti-glare film and mold {MANUFACTURING METHOD OF ANTIGLARE FILM, ANTIGLARE FILM AND MANUFACTURING METHOD OF MOLD}

This invention relates to the anti-glare film obtained by the manufacturing method of an anti-glare (anti glare) film, and its manufacturing method. Moreover, this invention relates to the gray scale pattern used for the manufacturing method of the said anti-glare film, and the manufacturing method of the metal mold | die used suitably for the manufacturing method of the said anti-glare film.

In an image display device such as a liquid crystal display, a plasma display panel, a cathode ray tube (cathode ray tube: CRT) display, an organic electroluminescence (EL) display, and the like, when external light shines on the display surface, visibility is remarkably impaired. Conventionally, in order to prevent such external light from shining, in a television or a personal computer that values image quality, a video camera or a digital camera used outdoors with strong external light, and a mobile phone which displays using reflected light, etc. The film layer for preventing the external light from shining is formed in the surface. This film layer is largely divided into a film having an antireflection treatment using interference by an optical multilayer film and a film having an antiglare treatment that blurs an image by scattering incident light by forming fine unevenness on the surface. do. Since the antireflective film which is an electron needs to form the multilayer film of uniform optical film thickness, cost becomes high. On the other hand, since the latter anti-glare film can be manufactured relatively inexpensively, it is widely used for large-scale personal computers, monitors, and the like.

Such an anti-glare film is conventionally applied by, for example, a method of forming a random surface unevenness on a base sheet by adjusting a film thickness on a base sheet by applying a resin solution in which fine particles are dispersed, and exposing the fine particles to a coating film surface. Is being manufactured. However, since the arrangement and the shape of the surface irregularities are influenced by the dispersion state, the application state, and the like of the fine particles in the resin solution, the antiglare film produced using the resin solution in which such fine particles are dispersed can obtain the surface irregularities as intended. It was difficult, and when setting the haze of anti-glare film low, there existed a problem that sufficient anti-glare effect was not acquired. Moreover, when such a conventional anti-glare film is arrange | positioned on the surface of an image display apparatus, the whole display surface becomes white light by scattered light, and the so-called "whitening" which becomes a dim color of a display tends to generate | occur | produce there was. In addition, with the recent sharpening of image display apparatuses, a so-called "sparkling" phenomenon in which the pixels of the image display apparatus and the surface irregularities of the anti-glare film interfere with each other, and as a result, a luminance distribution occurs and the display surface becomes difficult to see. There was a problem that it was easy to occur. In order to eliminate the glare, there have been attempts to scatter light by providing a difference in refractive index between the binder resin and the fine particles dispersed therein, but when such an anti-glare film is placed on the surface of the image display device, There was also a problem that contrast tends to be lowered by scattering of light.

On the other hand, there exists an attempt to express anti-glare only by the fine unevenness | corrugation formed in the surface of a transparent resin layer, without containing microparticles | fine-particles. For example, Japanese Unexamined Patent Application Publication No. 2002-189106 discloses a fine surface on which a three-dimensional ten-point average roughness and an average distance between adjacent convex portions on a three-dimensional roughness reference plane each satisfy a predetermined value on a transparent resin film. The anti-glare film in which the hardened | cured material layer of the ionizing radiation curable resin layer which has an unevenness | corrugation was laminated | stacked is disclosed. This anti-glare film is manufactured by hardening the ionizing radiation curable resin in the state which sandwiched the ionizing radiation curable resin between an embossing mold and a transparent resin film. However, even with the antiglare film disclosed in Japanese Patent Laid-Open No. 2002-189106, it was difficult to achieve sufficient antiglare effect, suppression of whitening, high contrast and suppression of glare.

Moreover, as a method of manufacturing the film in which the fine unevenness | corrugation was formed in the surface, the method of transferring the uneven | corrugated shape of the roll which has an uneven | corrugated surface to a film is known. As a method for producing a roll having such an uneven surface, for example, Japanese Patent Application Laid-Open No. 6-34961 discloses a cylindrical body made of metal or the like, and the surface of which is formed by electron engraving, etching, sandblasting, or the like. A method of forming irregularities by the method is disclosed. Further, Japanese Patent Laid-Open No. 2004-29240 discloses a method of producing an embossing roll by a beads shot method, and Japanese Patent Laid-Open No. 2004-90187 discloses a metal on the surface of the roll. The method of manufacturing an embossing roll is provided through the process of forming a plating layer, the process of mirror-polishing the surface of a metal plating layer, and the process of peening as needed.

However, in the state which blasted the surface of the embossing roll in this way, distribution of the uneven | corrugated diameter resulting from the particle size distribution of a blast particle generate | occur | produces, and it is difficult to control the depth of the recessed part obtained by blasting, and an anti-glare function is performed There was a problem in obtaining reproducibly excellent shapes of irregularities.

In addition, the above-mentioned Japanese Patent Laid-Open Publication No. 2002-189106 discloses that an uneven surface is formed by sandblasting or bead shot method, preferably using a roller chromium-plated on the iron surface. In addition, in order to improve durability at the time of use, it is preferable to use it after the chromium plating etc. on the surface in which the unevenness | corrugation was formed in this way, and to prevent hardening and corrosion There is also a description that it can be planned. On the other hand, in each of the examples of Japanese Patent Laid-Open No. 2004-45471 and Japanese Patent Laid-Open No. 2004-45472, chromium plating was performed on the surface of the iron core, and after liquid sand blasting treatment of # 250, chrome was again present. It is described to form a fine uneven shape on the surface by plating.

However, in the manufacturing method of such an embossing roll, since blasting and shot are performed on chromium plating with high hardness, unevenness | corrugation is hard to form and it was also difficult to control the shape of the unevenness | corrugation formed precisely.

Japanese Unexamined Patent Application Publication No. 2000-284106 discloses that after performing sand blasting on a substrate, an etching step and / or a thin film lamination step are performed. In addition, Japanese Patent Laid-Open No. 2006-53371 discloses that a substrate is polished, sand blasted, and then electroless nickel plating is performed. Japanese Unexamined Patent Application Publication No. 2007-187952 discloses that an embossed plate is produced by performing a copper plating or nickel plating on a substrate, followed by polishing, sandblasting, and then chromium plating. In addition, Japanese Unexamined Patent Publication No. 2007-237541 discloses an embossed plate by performing copper plating or nickel plating, followed by polishing, sandblasting, etching or copper plating, and then chrome plating. It is described. In the manufacturing method using these sand blasting processes, it is difficult to form the surface irregularities in a precisely controlled state, so that relatively large irregularities having a period of 50 µm or more in the surface irregularities are also produced. As a result, these large irregularities and pixels of the image display device interfere with each other, and thus there is a problem that "glare", which is difficult to see the display surface, occurs due to luminance distribution.

An object of the present invention, while being low haze, exhibits excellent anti-glare performance when applied to an image display device, and also prevents deterioration of visibility due to whitening, and is applied even when applied to a high-definition image display device. It is providing the method for manufacturing the anti-glare film which can express high contrast, without producing it, and the anti-glare film obtained by the manufacturing method. Further, another object of the present invention is to provide a gradation pattern used for the production method of the antiglare film, and a production method of a metal mold that is suitably used for the production method of the antiglare film.

This invention relates to the manufacturing method of the anti-glare film containing the process of forming an uneven surface on a transparent base material based on a gradation pattern. The gray scale pattern has a minimum side length of 15 mm or more, and the energy spectrum of the gray scale pattern exhibits a local maximum within a range of a spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 . In the manufacturing method of the anti-glare film of this invention, the uneven surface formed on the transparent base material is a repeating structure of the uneven surface unit which consists of the concave part and convex part corresponding to the gradation of the said gradation pattern (a plurality of uneven surface unit repeatingly arranged). Structure).

In the manufacturing method of the anti-glare film of this invention, the image data created by the calculator can be used suitably as a gradation pattern. It is preferable that the image data as the gradation pattern is binarized into white and black. When the gradation pattern is image data binarized in white and black, the uneven surface unit is composed of a concave portion and a convex portion corresponding to the gray level of the binarized image data, and specifically, a concave portion constituting the uneven surface unit. Or either of the convex portions corresponds to the area of the bag of binarized image data.

It is preferable that the process of forming the uneven | corrugated surface on the said transparent base material includes the process of producing the metal mold | die which has an uneven | corrugated surface based on the said gradation pattern, and transferring the uneven surface of the metal mold | die on the transparent base material.

Moreover, this invention provides the manufacturing method of the metal mold | die used suitably for the manufacturing method of the anti-glare film of the said invention. The manufacturing method of the metal mold | die of this invention is the 1st plating process which performs copper plating or nickel plating on the surface of the base material for metal mold | die, the grinding | polishing process of grinding | polishing the surface by which the plating was performed by the 1st plating process, and the polished surface A photosensitive resin film forming step of forming a photosensitive resin film, an exposure step of exposing the gray scale pattern on the photosensitive resin film, a developing step of developing a photosensitive resin film exposed with the gray scale pattern, and a developed photosensitive resin film are used as a mask. The etching process includes a first etching step of forming unevenness on the polished plating surface, a photosensitive resin film peeling step of peeling off the photosensitive resin film, and a second plating step of applying chromium plating on the formed uneven surface.

The manufacturing method of the metal mold | die of this invention includes the 2nd etching process which blunts the uneven shape of the uneven surface formed by the 1st etching process by an etching process between the photosensitive resin film peeling process and the 2nd plating process. desirable.

It is preferable that the uneven surface to which the chrome plating formed in the 2nd plating process is given is the uneven surface of the metal mold | die transferred on a transparent base material. That is, it is preferable to use the uneven surface on which chromium plating was performed as an uneven surface of the metal mold | die transferred on a transparent base material as it is, without performing the process of grinding | polishing the surface after a 2nd plating process.

It is preferable that the chromium plating layer formed by chromium plating in a 2nd plating process has a thickness of 1 micrometer-10 micrometers.

Moreover, in this invention, the length of the minimum one side used for the anti-glare film obtained by the manufacturing method of the anti-glare film of the said invention, and the manufacturing method of the anti-glare film of the said invention is 15 mm or more, and the energy spectrum is It relates to a gradation pattern exhibiting a local maximum within a range of a spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 . It is preferable that the gradation pattern of this invention is image data binarized by white and black.

According to the present invention, when applied to an image display device while being low haze, excellent anti-glare performance can be exhibited, and deterioration of visibility due to whitening can be prevented, and even when applied to a high-definition image display device, glare is generated. The anti-glare film which expresses high contrast can be manufactured with high reproducibility, without making it impossible.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which expands and shows a part of an example of the gradation pattern used preferably for the manufacturing method of the anti-glare film of this invention, and enlarges a part of the gradation pattern used at the time of metal mold manufacture of Example 1 and Example 3. It is a figure which shows.
It is a figure which shows typically a preferable example of the first half part of the manufacturing method of the metal mold | die of this invention.
It is a figure which shows typically a preferable example of the latter part of the manufacturing method of the metal mold | die of this invention.
It is a figure which shows typically the state in which side etching advances in a 1st etching process.
It is a figure which shows typically the state in which the uneven surface formed by the 1st etching process dulls by the 2nd etching process.
It is a figure which expands and shows a part of gradation pattern used at the time of metal mold manufacture of Example 2. FIG.
It is a figure which expands and shows a part of gradation pattern used at the time of metal mold manufacture of Comparative Examples 1-3.
It is a figure which expands and shows a part of gradation pattern used at the time of metal mold manufacture of the comparative example 4. FIG.
It is a figure which expands and shows a part of gradation pattern used at the time of metal mold manufacture of the comparative example 5. FIG.
It is a figure which expands and shows a part of gradation pattern used at the time of metal mold manufacture of the comparative example 6. FIG.
It is a figure which expands and shows a part of gradation pattern used at the time of metal mold manufacture of the comparative example 7. FIG.
FIG. 12 is a diagram showing a cross section at f _x = 0 of the energy spectrum G ² (f _x , f _y ) calculated from the gray scale patterns used in Examples 1 and ^2. FIG.

<Method for Producing Anti-glare Film>

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of this invention is described in detail. The manufacturing method of the anti-glare film of this invention is characterized by including the process of forming a fine uneven surface (fine uneven surface) on a transparent base material based on a specific gradation pattern. Here, the "gradation pattern" is typically used to form the fine uneven surface of the antiglare film, and means image data composed of two or three gradations or more gradations created by a calculator, but the image data It may also include data uniquely convertible (such as matrix data). Examples of data that can be uniquely converted into image data include data in which only coordinates and gradations of respective pixels are stored. By forming the concave portion and the convex portion on the transparent substrate so as to correspond to the gray scale of such a gradation pattern, it is possible to form the uneven surface unit corresponding to one gradation pattern on the transparent substrate. In the manufacturing method of the anti-glare film of this invention, the fine uneven surface formed on the transparent base material can be comprised by the repeating structure of the uneven surface unit formed by densely repeating two or more uneven surface units.

(Gradation pattern)

In the present invention, as the gradation pattern, a pattern having a minimum side length of 15 mm or more and an energy spectrum exhibiting a maximum value within a range of a spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 is used. By forming a fine concavo-convex surface on the transparent substrate based on such a gradation pattern, when it is low haze and it is applied to an image display apparatus, it exhibits the outstanding anti-glare performance and can prevent the fall of visibility by whitening, Even when applied to a high-definition image display apparatus, it becomes possible to provide an anti-glare film capable of expressing high contrast without causing glare.

In other words, by using a gray scale pattern in which the energy spectrum exhibits a maximum value within a range of a spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 , a fine uneven surface showing a specific spatial frequency distribution, more specifically, 10 µm to 50 µm The fine uneven surface containing the surface shape which has period as a main component can be formed precisely, and glare can fully be suppressed, expressing sufficient anti-glare effect (anti-glare effect etc.) by this. When the fine concavo-convex surface of the antiglare film contains a long period component of more than 50 µm, when disposed on the surface of a high-definition image display device, there is a tendency that glare tends to occur, and a short period component of less than 10 µm On the fine uneven surface containing bay, there exists a tendency for anti-glare effects, such as an anti-glare effect, to become inadequate.

In addition, in the antiglare film produced by repeatedly arranging the uneven surface units corresponding to a pattern to form a fine uneven surface, when the interference color due to interference with external light is seen or disposed on the surface of the image display device, moire (moire) In some cases, according to the present invention, an anti-glare film that is not only excellent in anti-shaking ability but also effectively prevents generation of interference colors and moire can be obtained by setting the length of at least one side of the gradation pattern to 15 mm or more. You can get it. In addition, even when the length of one minimum side of the gradation pattern is less than 15 mm, interference color and moire may not occur. When the length of the minimum side of the gradation pattern is less than 10 mm, interference color and moire tend to occur. Therefore, in order to reliably prevent the occurrence of interference colors and moire, it is preferable that the length of at least one side of the gradation pattern is 15 mm or more.

In addition, in the case where the uneven surface unit corresponding to a certain pattern is repeatedly arranged to form a fine uneven surface, when the surface of the antiglare film is observed by illuminating external light, the repeated shape (for example, based on the square pattern, the uneven surface of the square) Although the lattice-shaped line which forms the boundary line of each uneven | corrugated surface unit in the case of forming the fine uneven | corrugated surface formed by densely repeating the surface unit) is concerned, the minimum length of one side is 15 mm or more. In addition, by using the gradation pattern whose energy spectrum shows the maximum value in the range of the spatial frequency of 0.025 micrometer <^-1> -0.125 micrometer <^-1>, the anti-glare film which is very excellent in the visibility which this repeating pattern is not observed can be obtained.

Here, the "minimum length of one side" of a gradation pattern means the length of the shortest side among the sides which comprise the external shape of a gradation pattern. The external shape of the gradation pattern is not particularly limited as long as the length of at least one side is 15 mm or more, and examples thereof include polygons such as triangles, squares, and hexagons having sides of 15 mm or more. When the gradation pattern is repeatedly arranged adjacent to each other on a plane, it is preferable that the region where the pattern is not arranged is not formed and has an outline shape that can be densely filled. Thereby, when forming a fine uneven | corrugated surface on a transparent base material based on a gradation pattern, the generation | occurrence | production of the area | region in which unevenness | corrugation is not formed can be prevented. From this point of view, the external shape of the gradation pattern is preferably polygonal rather than having a curved line or the like. When the external shape of the gradation pattern is a polygon such as a triangle, a square, a hexagon, or the like, the length of each side may be the same or different. The length of the minimum one side of the gradation pattern is preferably 16 mm or more, and more preferably 20 mm or more. The upper limit of the length of at least one side of the gradation pattern is not particularly limited, but is preferably 300 mm or less from the viewpoint of suppressing an increase in the calculation load when producing image data by a calculator.

Next, the energy spectrum of a gradation pattern is demonstrated. As described above, in the gray scale pattern used in the present invention, the energy spectrum exhibits a local maximum within a range of a spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 . By forming a fine concavo-convex surface on the basis of the gradation pattern exhibiting such spatial frequency characteristics, it is possible to obtain an anti-glare film excellent in anti-glare performance and excellent in visibility with suppressed glare, whitening, interference color, moire and repetitive shape.

When the gradation pattern is image data, the energy spectrum of the gradation pattern converts the gradation pattern data into a gray scale of 256 gradations, and then represents the gradation of the gradation pattern data by the two-dimensional function g (x, y), The two-dimensional function g (x, y) obtained is Fourier transformed to calculate the two-dimensional function G (f _x , f _y ), and is obtained by squaring the obtained two-dimensional function G (f _x , f _y ). Here, x and y represent rectangular coordinates in the gradation pattern data plane (for example, the x direction is the horizontal direction of the gradation pattern as image data, and the y direction is the vertical direction of the gradation pattern as image data), f _x and f _y Denotes the spatial frequency in the x direction and the spatial frequency in the y direction, respectively.

In reality, since the gradation of each pixel is obtained as a set of discrete data points, the two-dimensional function g (x, y) representing the gradation of the image data is a discrete function. Therefore, the energy spectrum G ² (f _x ) is calculated by calculating the discrete function G (f _x , f _y ) by the Discrete Fourier Transform defined by the following formula (1), and squaring the obtained discrete function G (f _x , f _y ). , f _y ) is obtained. Here, (pi) in Formula (1) is a circumference, and i is an imaginary unit. M is the number of pixels in the x direction, N is the number of pixels in the y direction, l is an integer of -M / 2 or more and M / 2 or less, and m is an integer of -N / 2 or more and N / 2 or less. Δf _x and Δf _y are spatial frequency intervals in the x and y directions, respectively, and are defined by the following equations (2) and (3), respectively. (DELTA) x and (DELTA) y in Formula (2) and Formula (3) are horizontal resolution in an x-axis direction and a y-axis direction, respectively. In the case where the gradation pattern is image data, Δx and Δy are equal to the length in the x-axis direction and the length in the y-axis direction of one pixel, respectively. That is, when a gray scale pattern is created as image data of 6400 dpi, it is (DELTA) x = (DELTA) y = 4 micrometer, and when a gray scale pattern is created as image data of 12800 dpi, it is (DELTA) x = (DELTA) y = 2 micrometer.

(1)

(One)

(2)

(2)

(3)

(3)

As described later, the image data is a gradation pattern, when the writing dot of a number randomly as a pattern layout, or based on this, the energy spectrum G ² (f _x, f _y) are the horizontal, vertical, height In three-dimensional graphs of f _x , f _y , and energy spectra G ² (f _x , f _y ), respectively, point-symmetry around the origin of f _x = 0 and f _y = 0 is obtained. Thus, the "spatial frequency represents the maximum value of the energy spectrum" in the present invention, the energy spectrum G ² a view showing a section of the at f _x = 0 in the (f _x, f _y) (and the horizontal axis represents the spatial frequency f _y, the longitudinal axis It is set as the spatial frequency calculated | required from this two-dimensional graph which is an energy spectrum. In this two-dimensional graph, the spatial frequency f _{y on the} horizontal axis can be set to the absolute value of the spatial frequency f _y since the energy spectrum is symmetrical with respect to f _y = 0.

In the present invention, "energy spectrum shows a maximum value within the range of the spatial frequency 0.025 ㎛ ^-1 ~0.125 ㎛ ^-1" refers to the energy spectrum of the G ² (f _x, f _y) at _x = 0 f In the figure showing a cross section, the energy spectrum has a plurality of local maxima, and includes at least one of these local maxima located within a range of a spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 .

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which expands and shows a part of an example (specifically, the gradation pattern used at the time of metal mold manufacture of Example 1 and Example 3) used for the manufacturing method of the anti-glare film of this invention. . In the present invention, the specific shape pattern is a gradation pattern with, and the length of one side of at least 15 ㎜, also, particularly the energy spectrum showing the maximum value in the range of spatial frequencies 0.025 ㎛ ^-1 ~0.125 ㎛ ^-1 Although not limited, for example, as shown in FIG. 1, the pattern which randomly arranges many dots (white area | region in FIG. 1) may be sufficient. The gradation pattern shown in FIG. 1 is a two-gradation image data (image resolution: 12800 dpi) binarized in white and black, and a plurality of randomly arranged one kind of dots having a dot diameter of 16 µm. Moreover, this gradation pattern is a square whose one side is 20 mm, and the energy spectrum shows the maximum at the spatial frequency of 0.046 micrometer <^-1> .

As described above, in the case where a plurality of dots are randomly arranged to create a gradation pattern, a plurality of dots having one type of dot diameter may be randomly arranged, and a plurality of dots having a plurality of types of dot diameters are randomly arranged. You may also Although the average dot diameter (the average value of the dot diameter of all the dots in a pattern) of a dot is not specifically limited, Preferably it is 6 micrometers-30 micrometers. If the average dot diameter exceeds or is less than 30 ㎛ 6 ㎛ is, there is a case that the energy spectrum that does not represent the maximum value within the range of the spatial frequency 0.025 ㎛ ^-1 ~0.125 ㎛ ^-1.

In the case where the gradation pattern is image data, as a means for randomly drawing a plurality of dots, for example, by generating a pseudo random number sequence R [b] having a value from 0 to 1 for an image having a width WX and a height WY For example, the method of generating | generating many dots whose x coordinate of a dot center is WXxR [2xa-1] and ay coordinate is WYxR [2xa] is mentioned. Here, a and b are both natural numbers. As a method for generating a pseudo random number sequence, any pseudo random number generation method can be used as long as it has a sufficient period length that can correspond to the number of dots to be distributed, such as linear congruence, Xorshift, or Mersenne twister. Alternatively, the pattern data in which dots are randomly arranged may be generated by hardware that generates random numbers by not only pseudo-random numbers but also thermal noise.

In addition, the gradation pattern used by this invention may be pattern data obtained by performing a specific operation with respect to the pattern data formed by arranging many of the said dots at random. As such an operation, for example, (i) an operation of applying a high pass filter for removing low spatial frequency components consisting of spatial frequencies below a specific lower limit value B, and (ii) than a specific lower limit value B '. A low spatial frequency component consisting of a low spatial frequency and a high spatial frequency component consisting of a spatial frequency exceeding a specific upper limit value T 'are removed and a specific range of space ranging from the lower limit value B' to the upper limit value T '. And an operation of applying a band pass filter for extracting a spatial frequency component composed of frequencies.

According to the gray scale pattern obtained by applying the high pass filter of (iii), since the low spatial frequency component is removed from the spatial frequency component that can be included in the pattern formed by arranging a large number of dots, the period exceeds 50 µm. The fine uneven surface becomes more difficult to be formed, and it becomes possible to prevent the sparkling more effectively. The said lower limit (B) can be in the range of 0.02 micrometer <^-1> -0.05 micrometer < ^-1 >, for example.

Further, according to the gradation pattern obtained by applying the bandpass filter of (ii), since the low spatial frequency component and the high spatial frequency component are removed from the spatial frequency component that can be included in the pattern formed by arranging a large number of dots, The fine uneven surface having a period of more than 50 μm is more difficult to be formed, which makes it possible to prevent glare more effectively, and can improve the process reproducibility when forming the uneven surface on the transparent substrate based on the gradation pattern. . The lower limit value B 'is, for example, 0.01 μm ⁻¹ or more, and preferably 0.02 μm ⁻¹ or more. It is preferable that an upper limit T 'is 1 / (Dx2) micrometer <^-1> or less. Here, D (μm) is the resolution of the laser in the case of forming the uneven surface by resolving the resolution of the processing device (for example, using a laser drawing device to form the uneven surface) when forming the uneven surface on the transparent substrate. Spot diameter).

In the case where a gradation pattern is created by arranging a large number of dots at random, or when a high pass filter or a band pass filter is applied to the gradation pattern, a dot diameter, a dot density, a lower limit value of the high pass filter (B), and a lower limit value of the band pass filter (B By appropriately controlling ')', the upper limit value T 'and the like, it is possible to obtain a gradation pattern in which the energy spectrum exhibits the maximum value within the range of the spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 . It is preferable that dot density (the ratio of the area | region where the dot is drawn with respect to the whole gradation pattern area) is 20%-80%, More preferably, it is 40%-70%.

In the case where the step of forming the uneven surface on the transparent substrate includes a resist work using a laser drawing apparatus or the like, the gradation pattern used in the production method of the antiglare film of the present invention is image data binarized in white and black. It is preferable. This is because in the case of including a resist work using a laser drawing apparatus or the like, an uneven shape is usually formed by, for example, binary values of whether or not a laser is irradiated. The image data of three or more gradations can be converted into easily binarized image data by setting an appropriate threshold value in consideration of the ratio of the exposure area or the like in the resist or the like.

(Formation of the uneven surface based on the gradation pattern)

In the manufacturing method of the anti-glare film of this invention, a fine uneven surface is formed on a transparent base material based on said gray scale pattern. The minute uneven surface formed is comprised by the recessed part and convex part corresponding to the gray-scale of a gradation pattern. When the gradation pattern is image data binarized into white and black, either one of the concave portion or the convex portion constituting the fine uneven surface corresponds to the area of the bag of the binarized image data. In the present invention, the fine concavo-convex surface formed on the transparent substrate has a fine structure having a repeating structure in which concave-convex surface units composed of concave portions and convex portions corresponding to the gray scales of one gray scale pattern are closely and repeatedly arranged adjacently. Uneven surface may be sufficient. The fine concavo-convex surface having such a repeating structure may be formed by using pattern data created by repeatedly arranging two or more gradation patterns which are image data, and the fine concavo-convex surface (uneven surface unit) corresponding to one gradation pattern is sequentially formed. It can also form by repeating and forming. It is also possible to form a mask corresponding to one gradation pattern, to arrange the mask in a plurality of repetitive arrangements, and to perform full-surface exposure through the plurality of masks arranged and arranged.

As a specific method of forming a fine uneven surface on a transparent base material based on the said gradation pattern, the printing method, the pattern exposure method, the embossing method, etc. are mentioned, for example. In the printing method, for example, the above-described gradation pattern is printed on a transparent substrate and produced by flexographic printing, screen printing, inkjet printing using photocurable resin or thermosetting resin, and then dried or dried by actinic light or heating. By hardening, the anti-glare film of this invention can be manufactured.

For example, in flexographic printing, after producing a flexo plate, which is a convex plate based on the above-described pattern, applying a photocurable resin to the convex portion of the flexo plate, transferring the applied photocurable resin onto the transparent support, and then actinic light By hardening by, fine unevenness | corrugation based on the pattern mentioned above can be formed on a transparent support body. In the case of screen printing, a screen which is a stencil based on the above-described pattern is produced, and the above-mentioned pattern is printed on the transparent support using the screen and the photocurable resin, and then photocurable by actinic light. By hardening resin, fine unevenness | corrugation can be formed on a transparent support body. In the case of inkjet printing, fine irregularities can be formed on the transparent support by directly printing the above-mentioned pattern on the transparent support using a photocurable resin, and then curing the photocurable resin with actinic light. have. Since the fine concavo-convex formed by such a printing method generally has a steep inclination, and there exists a site | part in which the resin layer is not formed on the transparent support body, the photocurable resin is further coated and inclined on the fine concavo-convex formed by the printing method. It is preferable to smooth an angle and to form a resin layer in the whole surface on a transparent support body. In the pattern exposure method, after apply | coating photocurable resin on a transparent base material, pattern exposure is performed by direct drawing exposure by the laser which used the above-mentioned gradation pattern, or whole surface exposure through the mask which has the above-mentioned gradation pattern, After developing as needed, the anti-glare film of this invention can be manufactured by hardening by actinic light or heating.

In the direct drawing exposure by a laser, after apply | coating photocurable resin on a transparent support body, the above-mentioned pattern is directly drawn and exposed by a laser beam, the site | part exposed by development remains or melt | dissolves, and the remaining scene By irradiating actinic light to a chemical conversion resin and hardening completely, the fine unevenness | corrugation based on the pattern mentioned above can be formed on a transparent support body. Since fine indentations formed by the direct drawing exposure by such a laser generally have a steep inclination, it is preferable to further coat a photocurable resin on the fine unevenness formed by the direct drawing exposure by a laser to smooth the inclination angle. desirable. In front-side exposure through a mask, a mask having the above-described pattern is produced, the photocurable resin is coated on a transparent support, the photocurable resin is exposed through the mask, and the exposed portion is left in the developing step. Or by dissolving the remaining photocurable resin and irradiating the active light with the active light to completely cure the fine concavo-convex based on the above-described pattern. In the entire surface exposure through the mask, the inclination angle of the fine unevenness may be controlled by appropriately controlling the proximity gap, or may be controlled by manufacturing the mask as a gradation mask and controlling the exposure degree. In the embossing method, a mold having a fine concavo-convex surface is produced on the basis of the gray scale pattern described above, the concavo-convex surface of the manufactured mold is transferred onto a transparent substrate, and then the transparent substrate on which the concave-convex surface is transferred is peeled from the mold, The anti-glare film of this invention can be manufactured. Among these, it is preferable that the anti-glare film of this invention is manufactured by the embossing method from a viewpoint of forming a fine uneven surface precisely and reproducibly.

As an embossing method, the UV embossing method using a photocurable resin and the hot embossing method using a thermoplastic resin are illustrated. Especially, the UV embossing method is preferable from a productivity viewpoint.

UV embossing is a method of transferring the uneven surface of a metal mold | die to the photocurable resin layer by hardening | curing, forming a photocurable resin layer on the surface of a transparent base material, and pressing the photocurable resin layer to the uneven surface of a metal mold | die. Specifically, the ultraviolet curable resin is coated on the transparent substrate, and the ultraviolet curable resin is cured by irradiating ultraviolet rays from the transparent substrate side in a state in which the coated ultraviolet curable resin is in close contact with the uneven surface of the mold, and then the ultraviolet curable resin is cured. The uneven | corrugated shape of a metal mold | die is transferred to ultraviolet curable resin by peeling the transparent base material with which the ultraviolet curable resin layer after hardening was formed.

In the case of using the UV embossing method, the transparent substrate is a substantially optically transparent film, for example, a triacetyl cellulose film, a polyethylene terephthalate film, a polymethyl methacrylate film, a polycarbonate film, or a norbornene-based compound as a monomer. And resin films such as solvent cast films or extruded films of thermoplastic resins such as amorphous cyclic polyolefins.

The kind of ultraviolet curable resin in the case of using the UV embossing method is not specifically limited, A commercially available suitable thing can be used. Moreover, it is also possible to use the resin which can harden | cure even visible light which has a wavelength longer than an ultraviolet-ray by combining the photoinitiator suitably selected with ultraviolet curable resin. As ultraviolet curable resin, 1 type or 2 types or more of polyfunctional acrylates, such as a trimethylol propane triacrylate and pentaerythritol tetraacrylate, Irgacure 907 (made by Chiba Specialty Chemicals), Irgacure 184, for example. Resin composition containing photoinitiators, such as (the Chiba Specialty Chemicals company make) and Lucirin TPO (BASF company make), can be used suitably.

On the other hand, the hot embossing method is a method of pressing a transparent substrate made of a thermoplastic resin into a mold in a heated state, and transferring the surface irregularities of the mold to the transparent substrate. As a transparent base material used for a hot embossing method, what kind of thing may be sufficient as it is a substantially transparent thing, For example, polymethyl methacrylate, a polycarbonate, a polyethylene terephthalate, a triacetyl cellulose, an amorphous cyclic polyolefin which uses a norbornene-type compound as a monomer, etc. Solvent cast films or extruded films of thermoplastic resins may be used. These transparent resin films can also be used suitably also as a transparent base material for coating the ultraviolet curable resin in the UV embossing method demonstrated above.

<The manufacturing method of the metal mold | die for anti-glare film production>

Hereinafter, the manufacturing method of the metal mold | die which can be used suitably for the manufacturing method of the anti-glare film of this invention is demonstrated. It is a figure which shows typically a preferable example of the first half part of the manufacturing method of the metal mold | die of this invention. 2, the cross section of the metal mold | die in each process is shown typically. The manufacturing method of the metal mold | die of this invention is a [1] 1st plating process, [2] polishing process, [3] photosensitive resin film formation process, [4] exposure process, [5] developing process, [ 6] 1st etching process, [7] photosensitive resin film peeling process, and [8] 2nd plating process are contained fundamentally. Hereinafter, each process of the manufacturing method of the metal mold | die of this invention is demonstrated in detail, referring FIG.

[1] first plating process

In the manufacturing method of the metal mold | die of this invention, first, copper plating or nickel plating is given to the surface of the base material used for a metal mold | die. Thus, by performing copper plating or nickel plating on the surface of the base material for metal mold | die, the adhesiveness and glossiness of chrome plating in a subsequent 2nd plating process can be improved. That is, when chromium plating is performed on the surface of iron or the like, or when chromium plating is again performed after the unevenness is formed on the surface of the chrome plating by sandblasting or beads shot method, fine cracks are generated. , The uneven shape of the mold surface becomes difficult to control. On the other hand, such a problem can be eliminated by giving copper plating or nickel plating to the surface of a base material first. This is because copper plating or nickel plating has a high coating property and a strong smoothing action, and thus forms a flat and glossy surface by filling minute irregularities, cavities, and the like of the base material for a mold. By the characteristics of these copper plating or nickel plating, even if chromium plating is performed in the 2nd plating process mentioned later, the roughness of the chromium plating surface considered to be caused by the micro unevenness | corrugation and the cavity which existed in the base material It is eliminated, and generation | occurrence | production of a fine crack is reduced by the high coating property of copper plating or nickel plating.

Examples of copper or nickel used in the first plating step include respective pure metals. In addition, copper may be an alloy mainly composed of copper or an alloy mainly composed of nickel. It is a meaning containing copper and a copper alloy, and "nickel" is a meaning containing nickel and a nickel alloy. Copper plating and nickel plating may be performed by electrolytic plating or electroless plating, respectively, but electrolytic plating is employ | adopted normally.

When carrying out copper plating or nickel plating, if the plating layer is too thin, the influence of the underlying surface cannot be completely excluded, so the thickness thereof is preferably 50 µm or more. The upper limit of the thickness of the plating layer is not critical, but in view of cost and the like, the upper limit of the thickness of the plating layer is preferably set to about 500 µm.

In the manufacturing method of the metal mold | die of this invention, aluminum, iron, etc. are mentioned from a cost viewpoint as a metal material used suitably for formation of the base material for metal mold | die. It is more preferable to use lightweight aluminum from the convenience of handling. Aluminum, a railroad, and a pure metal may respectively be used here, and besides, an alloy mainly composed of aluminum or iron may be used.

In addition, the shape of the base material for metal mold | die may just be a suitable shape conventionally employ | adopted in the said field | area, For example, a cylindrical or cylindrical roll other than a flat plate shape may be sufficient. If a mold is produced using a roll base material, there exists an advantage that an anti-glare film can be manufactured in a continuous roll shape.

[2] polishing process

In the subsequent polishing step, the surface of the base material subjected to copper plating or nickel plating in the above-described first plating step is polished. Through this step, the substrate surface is preferably polished in a state close to the mirror surface. The reason for this is that in order to achieve a desired precision, the metal plate or the metal roll serving as the base material is often subjected to machining such as cutting or grinding, whereby traces of processing remain on the surface of the base material, and copper plating or nickel plating is performed. This is because even in this state, these processing traces may remain, and the surface may not be completely smoothed in the plated state. That is, even if the process described later is performed on the surface where such deep processing traces and the like remain, the irregularities such as the processing traces may be deeper than the irregularities formed after each process, and the influence of the processing traces and the like may remain. When manufacturing an anti-glare film using such a metal mold | die, it may have an unexpected effect on an optical characteristic. In FIG. 2 (a), the plate-shaped mold base material 7 is subjected to copper plating or nickel plating on the surface thereof in the first plating step (about the copper plating or nickel plating layer formed in this step). (Not shown) and the state which had the surface 8 mirror-polished by the grinding | polishing process is shown typically.

The method for polishing the surface of the substrate subjected to copper plating or nickel plating is not particularly limited, and any of mechanical polishing, electrolytic polishing and chemical polishing can be used. Examples of the mechanical polishing method include an ultrafine finishing method, a lapping, a fluid polishing method, a buff polishing method, and the like. As for the surface roughness after grinding | polishing, it is preferable that centerline average roughness Ra based on the specification of JISB0601 is 0.1 micrometer or less, and it is more preferable that it is 0.05 micrometer or less. If the centerline average roughness Ra after polishing is larger than 0.1 µm, there is a possibility that the influence of surface roughness after polishing remains on the uneven shape of the final mold surface. The lower limit of the center line average roughness Ra is not particularly limited, and since there is naturally a limit in terms of processing time and processing cost, there is no need to specify it in particular.

[3] photosensitive resin film forming step

In the following photosensitive resin film formation process, the photosensitive resin is apply | coated as the solution which melt | dissolved photosensitive resin in the solvent, and heated and dried to the polished surface 8 of the base material 7 for mirrors which performed mirror polishing by the above-mentioned grinding | polishing process, To form a film. FIG. 2B schematically shows a state in which the photosensitive resin film 9 is formed on the polished surface 8 of the base material for metal mold 7.

Conventionally well-known photosensitive resin can be used as photosensitive resin. As a negative photosensitive resin which has a property which a photosensitive part hardens | cures, For example, the monomer and prepolymer of an acrylic acid ester which has an acryl group or a methacryl group, a mixture of bis azide, and diene rubber, a polyvinyl cinnamate type compound, etc. are mentioned, for example. It is available. As the positive photosensitive resin having the property that the photosensitive portion is eluted by the development and only the unphotosensitive portion remains, for example, a wasteol resin system, a novolac resin system, or the like can be used. In addition, you may mix | blend various additives, such as a sensitizer, a development promoter, an adhesive modifier, and a coating property improving agent, with photosensitive resin as needed.

When applying these photosensitive resins to the polished surface 8 of the base material 7 for metal mold | die, in order to form a favorable coating film, it is preferable to dilute and apply in a suitable solvent. As the solvent, a cellosolve solvent, a propylene glycol solvent, an ester solvent, an alcohol solvent, a ketone solvent, a high polar solvent, or the like can be used.

As a method of applying the photosensitive resin solution, known methods such as meniscus coat, fountain coat, dip coat, rotary coating, roll coating, wire bar coating, air knife coating, blade coating, and curtain coating can be used. It is available. It is preferable to make the thickness of a coating film into the range of 1 micrometer-6 micrometers after drying.

[4] exposure process

In the following exposure process, the above-mentioned gradation pattern is exposed on the photosensitive resin film 9 formed in the above-mentioned photosensitive resin film formation process. What is necessary is just to select suitably the light source used for an exposure process according to the photosensitive wavelength, sensitivity, etc. of the apply | coated photosensitive resin, For example, g line (wavelength: 436 nm) of high pressure mercury lamp, h line (wavelength: 405 nm) of high pressure mercury lamp, I-line (wavelength: 365 nm), high-pressure mercury lamp, semiconductor laser (wavelength: 830 nm, 532 nm, 488 nm, 405 nm, etc.), YAG laser (wavelength: 1064 nm), KrF excimer laser (wavelength: 248 nm), ArF excimer laser (wavelength: 193 nm), F2 excimer laser (wavelength: 157 nm), etc. can be used.

In the manufacturing method of the metal mold | die of this invention, in order to form surface uneven | corrugated shape with high precision, it is preferable to expose the said gray scale pattern in the state controlled precisely on the photosensitive resin film in an exposure process. In the manufacturing method of the metal mold | die of this invention, in order to expose the said gradation pattern on a photosensitive resin film with high precision, it is based on the gradation pattern which is image data produced by the calculator, and the laser beam generate | occur | produces from the computer-controlled laser head. It is preferable to draw a pattern on the photosensitive resin film. When performing such laser drawing, the laser drawing apparatus for printing plate preparation can be used. Examples of such a laser drawing apparatus include Laser Stream FX (manufactured by Sync Laboratories).

In FIG.2 (c), the state which the pattern was exposed to the photosensitive resin film 9 is typically shown. When the photosensitive resin film is formed of negative photosensitive resin, crosslinking reaction of resin advances in the exposed area | region 10 by exposure, and the solubility with respect to the developing solution mentioned later falls. Therefore, in the developing step, the unexposed region 11 is dissolved by the developer, and only the exposed region 10 remains on the substrate surface to become a mask. On the other hand, when the photosensitive resin film is formed of positive photosensitive resin, the bond of resin is cut | disconnected by exposure in the exposed area | region 10, and the solubility to the developing solution mentioned later increases. Therefore, in the developing step, the exposed region 10 is dissolved by the developer, and only the unexposed region 11 remains on the substrate surface to become a mask.

[5] Development Process

In the following development process, when negative photosensitive resin is used for the photosensitive resin film 9, the unexposed area | region 11 melt | dissolves with a developing solution, and only the exposed area | region 10 remains on the base material for metal mold | die, It serves as a mask in the subsequent first etching process. On the other hand, when positive type photosensitive resin is used for the photosensitive resin film 9, only the exposed area | region 10 is melt | dissolved by the developing solution, and the unexposed area | region 11 remains on the base material for metal mold | die, and is continued 1st It acts as a mask in the etching process.

As the developing solution used in the developing step, a conventionally known one can be used. For example, inorganic alkalis, such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia water, 1st amines, such as ethylamine and n-propylamine, diethylamine, di-n-butylamine, etc. Tertiary amines such as amines, triethylamine, methyldiethylamine, alcoholamines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, trimethylhydroxyethylammonium hydroxide Alkaline aqueous solutions such as cyclic amines such as quaternary ammonium salts, pyrrole, and piperidine; And organic solvents such as xylene and toluene.

The developing method in the developing step is not particularly limited, and methods such as immersion development, spray development, brush development, and ultrasonic development can be used.

In FIG.2 (d), the state which performed image development process using the negative photosensitive resin for the photosensitive resin film 9 is typically shown. In FIG.2 (c), the unexposed area | region 11 melt | dissolves with a developing solution, and only the exposed area | region 10 remains on the surface of a base material, and becomes the mask 12. FIG. In FIG.2 (e), the state which performed image development process typically using positive photosensitive resin for the photosensitive resin film 9 is shown. In FIG. 2C, the exposed region 10 is dissolved by the developer, and only the unexposed region 11 remains on the substrate surface to form the mask 12.

[6] first etching process

In the following 1st etching process, after using the photosensitive resin film | membrane which remained on the surface of the metal mold | die base material after the above-mentioned image development process, the metal mold | die base material of a part without a mask is mainly etched, and an unevenness | corrugation is formed in the polished plating surface. It is a figure which shows typically a preferable example of the latter part of the manufacturing method of the metal mold | die of this invention. FIG. 3A schematically shows a state in which the mold base 7 in the portion 13 without a mask is etched mainly by the first etching step. The mold base 7 in the lower portion of the mask 12 is not etched from the surface of the mold base, but etching proceeds from the portion 13 without the mask as the etching proceeds. Therefore, near the boundary between the mask 12 and the portion 13 without the mask, the base material 7 for the mold under the mask 12 is also etched. In the vicinity of the boundary between the mask 12 and the portion 13 without the mask, the substrate 7 for the mold under the mask 12 is also etched, hereinafter referred to as side etching. In FIG. 4, the progress of side etching is shown typically. The dotted line 14 of FIG. 4 has shown the surface of the metal substrate for metal mold | die which changes with progress of an etching step by step.

The etching treatment in the first etching step is usually performed using a ferric chloride (FeCl ₃ ) solution, cupric chloride (CuCl ₂ ) solution, alkali etching solution (Cu (NH ₃ ) ₄ Cl ₂ ), or the like. Although it is performed by corroding a surface, strong acids, such as hydrochloric acid and a sulfuric acid, can also be used, and reverse electrolytic etching by applying the reverse electric potential at the time of electroplating can also be used. Since the concave shape formed on the base material for a metal mold | die at the time of an etching process differs with the kind of base metal, the kind of photosensitive resin film, the etching method, etc., it cannot say uniformly, but when etching amount is 10 micrometers or less, It is etched approximately isotropically from the metal surface in contact. Etching amount here is the thickness of the base material shaved by etching.

The etching amount in the first etching step is preferably 1 µm to 50 µm. In the case where the etching amount is less than 1 µm, almost no irregularities are formed on the metal surface and the mold becomes almost flat, so that the anti-glare property is not exhibited. Moreover, when etching amount exceeds 50 micrometers, the height difference of the uneven | corrugated shape formed in a metal surface becomes large, and there exists a possibility that whitening may generate | occur | produce in the image display apparatus which applied the anti-glare film produced using the obtained metal mold | die. The etching treatment in the first etching step may be performed by one etching treatment or may be performed by dividing the etching treatment into two or more times. When dividing an etching process into two or more times, it is preferable that the sum total of the etching amount in two or more etching processes is 1 micrometer-50 micrometers.

[7] photosensitive resin film peeling step

In the following photosensitive resin film peeling process, the remaining photosensitive resin film used as a mask in a 1st etching process is melt | dissolved and removed completely. In the photosensitive resin film peeling process, a photosensitive resin film is melt | dissolved using a peeling liquid. As the stripping solution, the same developer as that described above can be used. When the negative photosensitive resin film is used by changing pH, temperature, concentration, and immersion time, the photosensitive resin film in the exposed portion is completely dissolved and removed, and the positive type In the case of using the photosensitive resin film, the photosensitive resin film of the non-exposed part is completely dissolved and removed. The peeling method in the photosensitive resin film peeling step is not particularly limited, and methods such as immersion development, spray development, brush development, and ultrasonic development can be used.

3B schematically shows a state in which the photosensitive resin film used as the mask 12 in the first etching step is completely dissolved and removed by the photosensitive resin film peeling step. By etching using the mask 12 made of the photosensitive resin film, the first surface uneven shape 15 is formed on the surface of the mold base.

[8] second plating process

Subsequently, chrome plating is performed on the formed uneven surface (first surface uneven shape 15) to blunt the uneven surface shape. In FIG. 3C, the chromium plating layer 16 is formed on the first surface uneven shape 15 formed by the etching process of the first etching step, thereby making the surface unevener than the first surface uneven shape 15. The surface 17 of chromium plating] is shown.

In the present invention, chromium plating is employed on the surfaces of flat plates, rolls, and the like, which have gloss, high hardness, small coefficient of friction, and which can provide good release properties. Although the kind of chromium plating is not specifically limited, It is preferable to use chromium plating which expresses favorable gloss called so-called gloss chrome plating, decorative chromium plating, etc. 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 the electrolysis time, the thickness of the chromium plating can be controlled.

Although Japanese Patent Laid-Open Publication No. 2002-189106, Japanese Patent Laid-Open Publication No. 2004-45472, Japanese Patent Laid-Open Publication No. 2004-90187 and the like have been disclosed to employ chromium plating, they have been described with a base material before plating of a mold. Depending on the type of chromium plating, the surface may be rough after plating or a large number of minute cracks may occur due to chromium plating. As a result, the optical properties of the antiglare film obtained by using the mold may be in an undesired direction. Proceed. The metal mold | die of the state in which the plating surface was rough is not suitable for manufacture of an anti-glare film. The reason for this is that, in general, the plating surface is polished after chromium plating in order to eliminate tackiness, but as described later, polishing of the surface after plating is not preferable in the present invention. In the present invention, copper plating or nickel plating is performed on the base metal to solve such a problem that is likely to occur in chromium plating.

In addition, it is not preferable to perform plating other than chromium plating in a 2nd plating process. The reason for this is that in platings other than chromium, hardness and abrasion resistance are lowered, so that durability as a mold decreases, irregularities are worn out during use, and the mold is damaged. In the anti-glare film obtained from such a metal mold | die, it is highly unlikely that sufficient anti-glare function will be obtained, and also the possibility of a defect generate | occur | producing on a film will become high.

In addition, surface polishing after plating as disclosed in Japanese Patent Laid-Open No. 2004-90187 or the like described above is also undesirable in the present invention. That is, it is preferable to use the uneven surface on which chromium plating was performed as an uneven surface of the metal mold | die transferred on a transparent base material as it is, without performing the process of grinding | polishing the surface after a 2nd plating process. The reason for this is that since a flat portion is generated on the outermost surface by polishing, deterioration of the optical characteristics may occur, and since the control factor of the shape increases, shape control with good reproducibility becomes difficult. .

Thus, in the manufacturing method of the metal mold | die of this invention, by performing chromium plating on the surface in which the fine surface uneven | corrugated shape was formed, the uneven | corrugated shape becomes dull and the metal mold | die which the surface hardness became high is obtained. The unevenness at this time varies depending on the type of the underlying metal, the size and depth of the unevenness obtained from the first etching process, the type and thickness of the plating, and the like. The biggest factor is also the plating thickness. When the thickness of chromium plating is thin, the effect of blunting the surface shape of the unevenness obtained before chrome plating process is inadequate, and the optical characteristic of the anti-glare film obtained by transferring the uneven | corrugated shape on a transparent base material does not improve very much. On the other hand, when the plating thickness is too thick, the productivity is poor and furthermore, a projection-shaped plating defect called nodule occurs, which is not preferable. Therefore, it is preferable to exist in the range of 1 micrometer-10 micrometers, and, as for the thickness of chromium plating, it is more preferable to exist in the range which is 3 micrometers-6 micrometers.

It is preferable that the chromium plating layer formed in this 2nd plating process is formed so that Vickers hardness may be 800 or more, and it is more preferable to form so that it may be 1000 or more. The reason is that when the Vickers hardness of the chromium plating layer is less than 800, the durability at the time of use of the mold decreases, and the decrease in the hardness of the chromium plating may cause abnormalities in the plating bath composition, electrolytic conditions, etc. during the plating treatment. This is because there is a high possibility that it is likely to have an undesirable effect on the occurrence of defects.

Moreover, in the manufacturing method of the metal mold | die of this invention, the 2nd which dulls the uneven surface formed by the 1st etching process between the above-mentioned [7] photosensitive resin film peeling process and [8] 2nd plating process by an etching process. It is preferable to include an etching process. In a 2nd etching process, the 1st surface uneven | corrugated shape 15 formed by the 1st etching process which used the photosensitive resin film as a mask is blunted by an etching process. By this 2nd etching process, the steep part of the surface inclination in the 1st surface uneven | corrugated shape 15 formed by the 1st etching process disappears, and the optical characteristic of the anti-glare film manufactured using the obtained metal mold | die in the preferable direction Change. 5, the 1st surface uneven | corrugated shape 15 of the base material for metal mold | die 7 is blunted by the 2nd etching process, the steep part of surface inclination dulls, and the 2nd surface uneven | corrugated shape which has a gentle surface slope ( 18) is shown.

Similarly to the first etching step, the etching treatment of the second etching step also includes a ferric chloride (FeCl ₃ ) solution, cupric chloride (CuCl ₂ ) solution, and alkaline etching solution (Cu (NH ₃ ) ₄ Cl ₂ ) Although it is carried out by corroding the surface with the like, a strong acid such as hydrochloric acid or sulfuric acid may be used, or reverse electrolytic etching by applying a potential opposite to that of electroplating may be used. Since the dull state of the unevenness after the etching treatment is different depending on the type of the underlying metal, the etching method, and the size and depth of the unevenness obtained by the first etching step, it cannot be said uniformly. The biggest factor is the etching amount. Etching amount here is also the thickness of the base material shaved by etching similarly to a 1st etching process. If the etching amount is small, the effect of blunting the surface shape of the unevenness obtained by the first etching step is insufficient, and the optical properties of the antiglare film obtained by transferring the uneven shape on the transparent substrate are not very good. On the other hand, if the etching amount is too large, the uneven shape is almost eliminated, and the mold becomes almost flat. Therefore, the anti-glare property is not exhibited. Therefore, it is preferable to exist in the range of 1 micrometer-50 micrometers, and, as for etching amount, it is more preferable to exist in the range which is 4 micrometers-20 micrometers. Also about the etching process in a 2nd etching process, you may perform by one etching process similarly to a 1st etching process, and may divide and perform an etching process in 2 or more times. When dividing an etching process into two or more times, it is preferable that the sum total of the etching amount in two or more etching processes is 1 micrometer-50 micrometers.

By using the metal mold | die obtained by the manufacturing method of the metal mold | die of this invention, since the fine concavo-convex surface shape is precisely controlled and formed, it exhibits sufficient anti-glare property and does not generate whitening and arrange | positions on the surface of an image display apparatus. Even when it does, no glare occurs and it becomes possible to obtain an anti-glare film showing high contrast. In addition, it is possible to obtain an antiglare film in which interference color, moire generation and repeated pattern generation are effectively suppressed.

Yes

Although an Example is given to the following and this invention is demonstrated in more detail, this invention is not limited to these Examples.

[1] Spatial frequency measurement showing maximum value of energy spectrum of gradation pattern

The created grayscale pattern data was made into grayscale image data of 256 grayscales at 12800 dpi, and the grayscales were represented by a two-dimensional discrete function g (x, y). The obtained two-dimensional discrete function g (x, y) was discrete Fourier transformed to obtain a two-dimensional function G (f _x , f _y ). Two-dimensional function G (f _x, f _y) a square calculating a two-dimensional function G ² (f _x, f _y) of the energy spectrum, and the f _x = 0 in G ² (0, f _y) cross-section curve of [the horizontal axis is From the two-dimensional graph in which the spatial frequency is f _y and the vertical axis is the energy spectrum, the spatial frequency representing the maximum value of the energy spectrum was obtained. Here, in the "spatial frequency representing the maximum value of the energy spectrum" shown in Table 1 below, among the plurality of maximum values existing outside the position of the spatial frequency f _y = 0 µm ^-1 , the maximum is represented at the spatial frequency having the smallest absolute value. The corresponding spatial frequency of the maximum is described. The horizontal resolution of the pattern used for calculation was 2 micrometers for (DELTA) x and (DELTA) y. In addition, the calculation range was 1000 micrometers x 1000 micrometers.

[2] Measurement of haze of anti-glare film

The haze of the antiglare film was measured by the method specified in JIS K 7136. Specifically, haze was measured using a haze meter HM-150 type (manufactured by Murakami Color Research Institute) in accordance with this standard. In order to prevent curvature of an anti-glare film, it measured by bonding to a glass substrate so that an uneven surface might become a surface using an optically transparent adhesive. In general, when the haze increases, the image becomes dark when applied to the image display device, and as a result, the front contrast tends to decrease. For this reason, the lower one of the haze is preferable.

[3] Evaluation of antiglare performance of antiglare film

(Visual evaluation of repetitive shape, interference color, dancing, whitening)

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 a surface, and visually observed from the uneven surface side in a bright room where fluorescent lamps are turned on, and the presence or absence of a repeating color The presence or absence of non-dance of fluorescent lamps and the presence of whitening were visually evaluated. Repetitive shapes, interference colors, flickering and whitening were evaluated according to the following criteria in three steps of 1 to 3, respectively.

Repeating shape 1: No repeating shape is observed.

            2: A slight repeating shape is observed.

            3: The repeat shape is clearly observed.

Interference color 1: No interference color is observed.

            2: Interference color is slightly observed.

            3: The interference color is clearly observed.

No dance 1: No dance is observed.

            2: A slight dance is observed.

            3: Visibility is clearly observed.

Whitening 1: Whitening is not observed.

            2: Slight whitening is observed.

            3: Whitening is observed clearly.

(Evaluation of glitter and moire)

The polarizing plate of both front and back was peeled from commercial liquid crystal television (LC-32GH3 (made by Sharp Co., Ltd.)). Instead of these original polarizing plates, on both the back side and the display surface side, polarizing plates Sumikaran SRDB31E (manufactured by Sumitomo Kagaku Co., Ltd.) were bonded through an adhesive such that each absorption axis coincided with the absorption axis of the original polarizing plate, On the display surface side polarizing plate, the anti-glare film shown in each following example was bonded together through an adhesive so that the uneven surface might be a surface. In this state, the degree of glare and moire were evaluated in three steps by the following criteria by visual observation from a position about 30 cm away from the sample.

Flash 1: No flash is observed.

        2: A slight flash is observed.

        3: The flash is clearly observed.

Moire 1: No moire is observed.

        2: Moire is slightly observed.

        3: Moire is clearly observed.

&Lt; Example 1 >

It was prepared that a copper ballard plating was performed on the surface of an aluminum roll (A5056 by JIS) having a diameter of 200 mm. Copper ballad plating consists of a copper plating layer / thin silver plating layer / surface copper plating layer, and the thickness of the whole plating layer was set so that it might be set to about 200 micrometers. The copper plating surface was mirror-polished, the photosensitive resin was apply | coated to the polished copper plating surface, and it dried, and formed the photosensitive resin film. Subsequently, pattern data formed by successively arranging a plurality of gradation pattern data shown in FIG. 1 was exposed and developed on the photosensitive resin film with a laser beam. Exposure by laser light and development were performed using Laser Stream FX (manufactured by Sync Laboratories). Positive photosensitive resin was used for the photosensitive resin film. The gradation pattern data shown in FIG. ¹ is a pattern in which a large number of dots having a dot diameter of 16 µm are randomly arranged, and the energy spectrum has a maximum at a spatial frequency of 0.046 µm ^-1 . In addition, the gradation pattern data shown in FIG. 1 was created as a square whose side is 20 mm.

Then, the 1st etching process was performed with the cupric chloride liquid. The etching amount at that time was set to be 3 micrometers. The photosensitive resin film was removed from the roll after the first etching treatment, and the second etching treatment was again performed with cupric chloride liquid. The etching amount at that time was set to be 10 micrometers. Then, the chrome plating process was performed and the metal mold | die A was produced. At this time, the chromium plating thickness was set to 4 µm.

Photocurable resin composition GRANDIC 806T (manufactured by Dainippon Ink & Chemicals Co., Ltd.) was dissolved in ethyl acetate to obtain a solution having a concentration of 50% by weight, and further, lucirin TPO (manufactured by BASF, chemical name: 2) as a photopolymerization initiator. (4,6-trimethylbenzoyldiphenylphosphine oxide) was added 5 parts by weight per 100 parts by weight of the curable resin component to prepare a coating solution. On the 80-micrometer-thick triacetyl cellulose (TAC) film, this coating liquid was apply | coated so that the coating thickness after drying might be set to 10 micrometers, and it dried for 3 minutes in the dryer set to 60 degreeC. The film after drying was pressed by the rubber roll so that the photocurable resin composition layer might become the metal mold | die side to the uneven surface of the metal mold A obtained previously. In this state, the light from the high-pressure mercury lamp of 20 mW / cm <2> intensity | strength was irradiated so that it might become 200 mJ / cm <2> by h-ray-converted light quantity, and the photocurable resin composition layer was hardened. Thereafter, the TAC film was peeled from the mold together with the cured resin to prepare a transparent anti-glare film A made of a laminate of a cured resin having irregularities on the surface and a TAC film.

<Example 2>

As the gradation pattern exposed by the laser beam, the mold was carried out in the same manner as in Example 1 except that the first etch process and the second etch process were performed at the etching amounts shown in Table 1 using the gradation pattern shown in FIG. B was obtained. An anti-glare film B was produced in the same manner as in Example 1 except that the obtained mold B was used. The gradation pattern data shown in Fig. 6 is a pattern in which a large number of dots having a dot diameter of 12 mu m are randomly arranged, and the energy spectrum has a maximum at a spatial frequency of 0.056 mu m ^-1 . In addition, the gradation pattern data shown in FIG. 6 was created as a square with one side 100 mm.

<Example 3>

As the gradation pattern exposed by the laser beam, the first etching treatment was performed using the same gradation pattern as used in Example 1 except that the pattern data was prepared as a square having a side length of 16 mm. And the metal mold | die C was obtained like Example 1 except having performed the 2nd etching process. An anti-glare film C was produced in the same manner as in Example 1 except that the obtained mold C was used.

<Comparative Example 1 and Comparative Example 2>

As the gray scale pattern exposed by the laser beam, the first etching treatment and the second etching treatment are performed at the etching amounts shown in Table 1 using the gray scale pattern data shown in FIG. 7 prepared as a square having a side length of 20 mm. The metal mold | die D and the metal mold | die E were obtained like Example 1 except having performed. Except using the obtained metal mold | die D and metal mold | die E, the anti-glare film D and the anti-glare film E were produced like Example 1. The gradation pattern data shown in FIG. 7 is a pattern in which a large number of dots having a dot diameter of 36 mu m are randomly arranged, and the energy spectrum has a maximum at a spatial frequency of 0.017 mu m ⁻¹ . The energy spectrum of the gradation pattern data shown in FIG. 7 does not have a maximum value within the range of the spatial frequency of 0.025 μm ^{−1 to} 0.125 μm ⁻¹ .

Comparative Example 3

As the gradation pattern exposed by the laser beam, the mold F was obtained in the same manner as in Comparative Example 1 except that the gradation pattern data shown in FIG. 7 created as a square having a side length of 10 mm was used. An anti-glare film F was produced in the same manner as in Comparative Example 1 except that the obtained mold F was used.

<Comparative Examples 4-7>

As the gradation pattern exposed by laser light, Example 1 and 2 were performed except that the 1st etching process and the 2nd etching process were performed with the etching amount shown in Table 1 using the gradation pattern shown in FIGS. 8-11, respectively. In the same manner, molds G to J were obtained. Except for using obtained molds G-J, it carried out similarly to Example 1, and produced anti-glare films G-J. The gradation pattern data shown in Fig. 8 is a pattern in which a large number of dots having a dot diameter of 16 µm are randomly arranged, and the energy spectrum has a maximum at a spatial frequency of 0.056 µm ^-1 . In addition, the gradation pattern data shown in FIG. 8 was created as a square whose side is 10 mm. The gradation pattern data shown in Fig. 9 is a pattern in which a large number of three kinds of dots having a dot diameter of 14 탆, 18 탆 and 22 탆 are randomly arranged, and the energy spectrum has a maximum at a spatial frequency of 0.042 탆 ⁻¹ . In addition, the tone pattern data shown in FIG. 9 was created as a square whose side is 2 mm. The gradation pattern data shown in Fig. 10 is a pattern in which a large number of dots having a dot diameter of 20 mu m are randomly arranged, and the energy spectrum has a maximum at a spatial frequency of 0.033 mu m ^-1 . In addition, the gradation pattern data shown in FIG. 10 was created as a square whose side is 1 mm. The gradation pattern data shown in Fig. 11 is a pattern in which a large number of dots having a dot diameter of 22 mu m are randomly arranged, and the energy spectrum has a maximum value at a spatial frequency of 0.033 mu m ^-1 . In addition, the gradation pattern data shown in FIG. 11 was created as a square whose side is 1 mm.

Spatial frequency which shows the etching amount of the 1st etching process and the 2nd etching process at the time of manufacture of metal molds A-J, the dot diameter of the gradation pattern used for preparation, and the local maximum of an energy spectrum [as mentioned above, the space described in this column] A frequency is a plurality of frequencies existing outside the position of the spatial frequency f _y = 0 μm ⁻¹ in G ² (0, f _y ), which is a cross-sectional curve of f _x = 0 of the energy spectrum G ² (f _x , f _y ). Among the maximum values, the absolute value is the corresponding spatial frequency of the maximum value indicating the maximum at the smallest spatial frequency], the shape of the gradation pattern, and the length of the minimum side. 12 is a diagram showing a cross section at f _x = 0 of the energy spectrum G ² (f _x , f _y ) calculated from the gradation patterns used in Example 1 and Example 2. FIG. The numerical value on the horizontal axis of FIG. 12 has shown the absolute value of the spatial frequency f _y .

In addition, in Table 2, the measurement result of the haze of the obtained anti-glare film, and the evaluation result of anti-glare performance are shown.

From the evaluation result of Table 2, in the anti-glare films A-C of Examples 1-3 obtained by the manufacturing method of this invention, the minimum one side length is 15 mm or more, and an energy spectrum has a spatial frequency of 0.025 micrometer <^-1> The mold is fabricated using a gradation pattern showing a maximum value within the range of ˜0.125 μm ⁻¹ , and the fine concavo-convex surface is formed by transferring the concave-convex surface of the obtained mold, so that the anti-dancing ability is excellent, and the glare, whitening, and repetition are repeated. It turns out that it is an anti-glare film excellent in visibility that a shape, an interference color, and a moire are not observed. In addition, since the anti-glare films A to C exhibit good anti-glare performance while being low haze, it is possible to provide an image display device having high contrast while exhibiting excellent anti-glare properties.

On the other hand, in the antiglare films D and E of Comparative Examples 1 and 2, since the length of the minimum side of the gray scale pattern used was 20 mm, interference colors and moire did not occur, but the energy spectrum had a spatial frequency of 0.025 µm ^{-1 to} 0.125 µm. ^{Since the} maximum value is not displayed within the range of ^-1, the effect of suppressing the glare and whitening is not sufficient. In addition, by using a gray scale pattern in which the energy spectrum does not exhibit a maximum value within the above range, a repeating shape (lattice-shaped lines constituting the outline of the uneven surface unit corresponding to the repeatedly arranged gray scale pattern) was observed.

In addition, in the anti-glare films F to J of Comparative Examples 3 to 7, since the length of the minimum side of the gray scale pattern used is 1 mm to 10 mm, the energy spectrum is in the range of the spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 . Even when the maximum value was expressed at, the repeating shape was observed. Moreover, interference color and moire were also observed in the anti-glare films H-J of Comparative Examples 5-7 whose length of the minimum one side of the used gradation pattern is less than 10 mm. Further, in the anti-glare film F of Comparative Example 3, since the energy spectrum of the gradation pattern using the maximum value does not indicate the extent of the spatial frequency 0.025 ㎛ ^-1 ~0.125 ㎛ ^-1, the glare was observed.

Claims (10)

A step of forming an uneven surface on the transparent substrate based on the gradation pattern,
The gray scale pattern has a minimum side length of 15 mm or more, and the energy spectrum of the gray scale pattern exhibits a local maximum within a range of a spatial frequency of 0.025 µm ^{-1 to} 0.125 µm ^-1 ,
The said uneven | corrugated surface is a manufacturing method of the anti-glare film which is comprised by the repeating structure of the uneven | corrugated surface unit which consists of the recessed part and convex part corresponding to the gradation of the said gradation pattern. The method of claim 1, wherein the gradation pattern is image data binarized into white and black,
The manufacturing method of the anti-glare film in which any one of the recessed part or convex part which comprises the said uneven surface unit corresponds to the area | region of the bag of the said binarized image data. The process of claim 1, wherein the step of forming the uneven surface on the transparent substrate comprises a step of producing a mold having an uneven surface based on the gradation pattern, and transferring the uneven surface of the mold onto the transparent substrate. The manufacturing method of an anti-glare film containing. As a method of manufacturing the mold according to claim 3,
1st plating process which performs copper plating or nickel plating on the surface of the base material for metal molds,
A polishing step of polishing the surface on which the plating is performed by the first plating step,
A photosensitive resin film forming step of forming a photosensitive resin film on the polished surface,
An exposure step of exposing the gradation pattern on the photosensitive resin film;
A developing step of developing the photosensitive resin film exposed with the gray scale pattern;
A first etching step of performing an etching treatment using the developed photosensitive resin film as a mask to form irregularities on the polished plating surface;
A photosensitive resin film peeling step of peeling the photosensitive resin film,
2nd plating process which performs chromium plating on the formed uneven surface
Manufacturing method of a mold comprising a. The manufacturing method of the metal mold | die of Claim 4 containing the 2nd etching process which blunts the uneven | corrugated shape of the uneven surface formed between the said photosensitive resin film peeling process and the said 2nd plating process by an etching process. The manufacturing method of the metal mold | die of Claim 4 whose uneven surface by which the chrome plating formed in the said 2nd plating process was given is the uneven surface of the metal mold | die transferred on the said transparent base material. The method for manufacturing a mold according to claim 4, wherein the chromium plating layer formed by chromium plating in the second plating step has a thickness of 1 µm to 10 µm. The anti-glare film manufactured by the manufacturing method of the anti-glare film of Claim 1. As a gradation pattern used for the manufacturing method of the anti-glare film of Claim 1,
A gradation pattern and the length of one side of at least 15 ㎜, energy spectrum, it represents the maximum value in the range of spatial frequencies 0.025 ㎛ ^-1 ~0.125 ㎛ ^-1. The gradation pattern according to claim 9, which is image data binarized into white and black.

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