KR20160015160A - Anti-glare film - Google Patents

Abstract

[PROBLEMS] To provide an antiglare film which has low haze, excellent antifogging property at a wide viewing angle, and can sufficiently suppress the occurrence of whitening and flashing when placed in an image display device.
[MEANS FOR SOLVING PROBLEMS] An optical recording medium comprising a transparent support and an antiglare layer having a fine surface irregularity formed thereon, wherein the total haze is 0.1% or more and 3% or less, the surface haze is 0.1% or more and 2% The average value of the angles is not less than 0.2 DEG and not more than 1.2 DEG, the standard deviation of the tilt angle is not less than 0.1 DEG and not more than 0.8 DEG, the area of the polygon formed when the surface of the convex portion of the convex- Is not less than 50 μm ^{2 and not} more than 150 μm ² , and the coefficient of variation of the area of the polygon is not less than 40% and not more than 80%.

Description

ANTI-GLARE FILM

The present invention relates to an anti-glare film having excellent anti-glare properties.

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 has a display And an antiglare film is disposed on the surface.

As the antiglare film, a transparent film having a surface relief shape is mainly studied. Such an antiglare film reduces scattering by scattering and reflecting external light (external light scattering light) with its surface relief shape, and exhibits antistatic properties. However, when the external light scattering light is strong, so-called " whitening " occurs in which the entire display surface of the image display device becomes whitish or the display becomes blurred. In addition, the surface irregularities of the pixels of the image display device and the antiglare film may interfere with each other, resulting in a so-called " flashing " In view of the above, the antiglare film is required to sufficiently prevent occurrence of these " whitening " and " flashing "

Therefore, for example, Patent Document 1 discloses that an anti-glare film which does not cause flashing even when placed in a high-definition image display device and is sufficiently prevented from whitening, has a fine surface irregularity shape formed on a transparent substrate, (Pa / PSm) of an arithmetic average height (Pa) and an average length (PSm) in the cross-section curve is not less than 0.005 and not more than 0.012 Of the surface irregularities of the surface irregularities is not more than 50%, and the ratio of the surface having the oblique angles of not more than 6% is 90% or more.

The anti-glare film disclosed in Patent Document 1 eliminates the surface irregularities having a period of about 50 탆 which makes it easy to cause flashing by making the average length (PSm) in an arbitrary cross-sectional curve very small, Can be effectively suppressed. However, in the antiglare film disclosed in Patent Document 1, when it is intended to make the haze smaller (when it is desired to have a lower haze), the retardation when the display surface of the image display device in which the antiglare film is arranged is observed in the oblique direction is decreased There was a case. Therefore, the anti-glare film disclosed in Patent Document 1 still had room for improvement in terms of the retardation at a wide observation angle.

Patent Document 1: Japanese Patent Application Laid-Open No. 2007-187952

An object of the present invention is to provide an antiglare film which has low haze, excellent antifogging property at a wide viewing angle, and can sufficiently suppress the occurrence of whitening and flashing when placed in an image display device.

Means for Solving the Problems The present inventors have intensively studied in order to solve the above problems, and have completed the present invention. That is, the present invention provides an antiglare film comprising a transparent support and an antiglare layer having a fine surface relief shape formed thereon,

The total haze is 0.1% or more and 3% or less,

A surface haze of 0.1% or more and 2% or less,

The average value of the inclination angles of the surface irregularities is 0.2 to 1.2 degrees and the standard deviation of the inclination angles is 0.1 to 0.8 degrees,

The average value of the area of the polygon formed when the surface of the convex portion of the convexo-concave shape is formed as the center point is Voronoi tesselation is 50 탆 ² or more and 150 탆 ² or less, An antiglare film having an area variation coefficient of 40% or more and 80% or less is provided.

In this antiglare film,

The sum Tc of transmission sharpness measured using five kinds of optical combs having the widths of the light shielding portion and the transmission portion of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm is 375% or more,

The sum Rc (45) of the reflection sharpness measured at an incident angle of light of 45 ° is 180% or less using four kinds of optical combs having the widths of the shielding portion and the transmitting portion of 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm,

It is preferable that the sum Rc (60) of the reflection sharpness measured at an incident angle of light of 60 占 using the four types of optical combs having the widths of the shielding portion and the transmitting portion of 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm is 240% or less Do.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an antiglare film having a low haze, a sufficient diffusibility at a wide viewing angle, and sufficiently suppressing whitening and glare when placed in an image display device.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view for explaining inclination angles of surface irregularities of an antiglare film. FIG.
2 is a schematic view for explaining a method of measuring the inclination angle of the surface of the antiglare film.
3 is a Voronoi diagram showing an example of Voronoi division.
4 is a perspective view schematically showing an algorithm of determining the convexity of the antiglare film.
5 is a diagram schematically showing a preferable example of the first half of the method for manufacturing a mold.
Fig. 6 is a diagram schematically showing a preferable example of the second half of the manufacturing method of the metal mold.
Fig. 7 is a diagram schematically showing an arrangement example of a device suitably used in producing an antiglare film. Fig.
8 is a diagram schematically showing an appropriate preliminary curing step in the production of an antiglare film.
9 is a plan view schematically showing a unit cell for evaluation of flashing.
10 is a cross-sectional view schematically showing a device for evaluating flashing.
11 is a view showing a part of patterns used in Examples 1 to 3 and Comparative Example 1. Fig.
12 is a diagram showing a part of the pattern used in the fourth embodiment.
13 is a diagram showing a part of the pattern used in the fifth embodiment.
14 is a diagram showing a part of a pattern used in Comparative Example 2. Fig.

Hereinafter, the preferred embodiments of the present invention will be described with reference to the drawings as necessary, but the dimensions and the like described in the drawings are arbitrary for easy viewing.

In the antiglare film of the present invention, the average value of the inclination angles of the surface irregularities is 0.2 to 1.2 degrees, the standard deviation of the inclination angles is 0.1 to 0.8 degrees, and the peak of the convex portions The average value of the area of the polygon formed when the Voronoi is divided on the surface is not less than 50 μm ^{2 and not} more than 150 μm ² and the coefficient of variation of the area of the polygon is not less than 40% and not more than 80%.

First, a method of obtaining the area of the polygon formed when the Voronoi is divided on the surface of the antiglare film of the present invention, taking the average value and the standard deviation of the inclination angle and the apex of the convex portion of the convex and concave surface as the origin .

[Average value and standard deviation of inclination angle]

In the image display apparatus to which the antiglare film is applied, it is effective to make the surface irregularities of the antiglare film exhibit a specific inclination angle distribution in effectively preventing the whitening while giving excellent antiglare performance. Thus, in the antiglare film of the present invention, the average value of the inclination angles of the surface irregularities is 0.2 to 1.2 degrees, and the standard deviation of the inclination angles is 0.1 to 0.8 degrees. When the average value of the tilt angles is less than 0.2 deg., The irregularities of the surface become a substantially flat surface, and there is a possibility that sufficient antiglare performance can not be exhibited. On the other hand, when the average value exceeds 1.2 deg., The individual inclination angles become sharp, and light from the surroundings can be easily condensed, so that the image display device provided with such an antiglare film tends to cause whitening. Further, when the standard deviation of the tilt angle is less than 0.1 deg., The surface irregularity shape becomes uniform, and there is a possibility that sufficient antireflection performance may not be exhibited. On the other hand, when the standard deviation is more than 0.8 deg., Even if the average value is within the predetermined range, there is a region where the inclination angle is steep at the surface irregularity shape. In the image display device having such an antiglare film, . The average value of the inclination angles of the surface relief shapes is preferably 0.5 to 1.2 degrees, and the standard deviation of the inclination angles is preferably 0.3 to 0.7 degrees.

A method of obtaining an average value and a standard deviation of the tilt angles will be described. In Fig. 1, the surface of the antiglare film is shown in a schematic perspective view. Referring to this figure, the antiglare film (1) has fine irregularities (2) on its surface. The term "tilt angle of the surface irregularity shape" in the present invention means a tilt angle of the surface of the antiglare film 1 at an arbitrary point P on the surface of the antiglare film 1 shown in FIG. 1, the normal line direction 5 of the film, , The angle (?) Formed by the local normal line (6). The angle (?) Formed by the local normal line (6) affects the influence of the unevenness at the point P. In Fig. 1, the orthogonal coordinates in the film plane are represented by (x, y), and the plane of the entire film is represented by the projection plane 3. The inclination angle of the surface irregularity shape can be obtained from the three-dimensional information of the surface shape measured by a confocal microscope, an interference microscope, an atomic force microscope (AFM), or the like.

2 is a schematic view for explaining a method of measuring the inclination angle of the surface relief shape. As shown in FIG. 2, a point of interest A on a virtual plane FGHI indicated by a dotted line is determined on the film average surface 1, and a point A on the x-axis passing through the point A The points B and D are symmetrically symmetrical with respect to the point A and the points C and E are symmetrically arranged with respect to the point A in the vicinity of the point A on the y-axis passing the point A, The points Q, R, S, and T on the film surface corresponding to C, D, and E are determined. In Fig. 2, the orthogonal coordinates in the film plane are represented by (x, y), and the coordinates in the film thickness direction are represented by z. The plane FGHI is defined by a straight line parallel to the x axis passing through point C on the y axis and a straight line parallel to the x axis passing through point E on the y axis and parallel to the y axis passing through point B on the x axis, And a straight line parallel to the y-axis passing through the point D on the x-axis. 2, the position of the actual film surface is on the upper side with respect to the plane FGHI in the film average plane 1. However, depending on the position of the point of interest A, (FGHI) in the plane (1), or may come to the lower side.

The inclination angles of the obtained surface shape data are set such that a point P on an actual film surface corresponding to the target point A and a point Q on an actual film surface corresponding to four points B, C, D, Obtained by averaging the normal vectors 6a, 6b, 6c and 6d of the polygon 4 plane, that is, the four triangles PQR, PRS, PST and PTQ, drawn by the total of five points of R, S and T, Can be obtained by finding the polar angle of the vector (6). After obtaining the tilt angle with respect to each measurement point in this manner, the average value and the standard deviation of the tilt angle are calculated.

When an antiglare film is produced by applying a resin solution in which fine particles are dispersed on a transparent support to form random irregularities on the transparent support by exposing the fine particles to the surface of the coating film, the average value of the inclination angles Is in the range of 0.2 占 to 1.2 占 and the standard deviation of the tilt angle is 0.1 占 to 0.8 占 the particle size and dispersion state of the fine particles and the film thickness of the coating film can be adjusted. Generally, if the particle size of the fine particles is constant, by increasing the film thickness of the coating film, the average value of the tilt angle becomes small. Further, the better the dispersion state of the fine particles, that is, the more uniformly the fine particles are arranged on the transparent support, the smaller the standard deviation of the tilt angle.

On the other hand, when the UV embossing method, which is a preferred method for producing the antiglare film of the present invention to be described later, is adopted, the amount of etching in the second etching step for manufacturing the mold is adjusted, Can be obtained. By increasing the etching amount of the second etching step, the average value and the standard deviation of the inclination angle can be reduced.

[Area of the polygon formed when the irregular surface is divided by the Voronoi with the apex of the convex portion as the center point]

Regarding the concavo-convex shape of the surface of the antiglare film, the area of the polygon formed when the Voronoi is divided on the surface of the corrugation of the convex portion will be described. First, the Voronoi division will be described. When a plurality of points (referred to as a point) are arranged on a plane, a drawing which is obtained by dividing the plane according to which point is nearest to an arbitrary point in the plane, And the division is called Voronoi division. Fig. 3 shows an example in which Voronoi is divided on the surface of the antiglare film, with the apex of the convex portion serving as a common point. In this figure, rectangular polygons (27, 27) each having a square point 26, 26 as a point are formed by Voronoi division, and a Voronoi region or a Voronoi polygon Called Voronoi polygon in the following. In this figure, the portions 28 and 28 which are thinly painted around are described later. In the Voronoi diagram, the number of spots and the number of Voronoi polygons coincide. The area of the polygon formed when the Voronoi is divided on the surface of the convex portion of the convex portion of the surface is the area of the Voronoi polygon.

In order to obtain the average value and the coefficient of variation of the area of the Voronoi polygon obtained by dividing the Voronoi segment obtained by dividing the apex of the convex portion on the surface of the antiglare film into a confocal microscope, The three-dimensional coordinate values of the points on the surface of the antiglare film are measured, and then the Voronoi is divided by the algorithm described below to calculate the average value of the areas of the Voronoi polygon and the variation coefficient. When measuring the surface shape, it is preferable that the measurement region is 150 占 퐉 占 150 占 퐉 or more and 500 占 占 占 500 占 퐉 or less in order to precisely measure the micro concavo-convex surface of the antiglare film while reducing errors. In addition, it is preferable to measure the area of three or more points and take the average value as the measured value.

A Voronoi splitting method in which the peak of the convex portion of the fine concavo-convex surface of the antiglare film is taken as the spots is described in detail. First, the apex of the convex portion of the fine uneven surface is obtained. That is, when attention is paid to an arbitrary point on the surface of the antiglare film, when there is no point having a higher elevation than the noted point around the point, the point is referred to as the apex of the convex portion, And the Voronoi division is performed. More specifically, as shown in Fig. 4, attention is paid to an arbitrary point 21 on the surface of the antiglare film, and the point 21 of the antiglare film having a radius of 2.5 占 퐉 When there is no point having a higher altitude than the noted point 21 among points on the antiglare film surface 22 included in the projection plane 24 of the circle when the circle is drawn, It is determined to be a vertex. Here, the range for comparing the elevation is set within the range of the circle 24 having a radius of 2.5 占 퐉 in order to eliminate the influence of the high-frequency surface relief shape which hardly contributes to the antiglare property and flashing of the antiglare film.

Then, the apex of the obtained convex portion is projected onto the antiglare film reference surface 23. Thereafter, all the three-dimensional coordinates obtained by the measurement of the surface shape are projected on the reference plane, and all the projected points are attributed to the nearest neighboring points to divide the Voronoi and obtain the area of the polygon obtained by dividing, The average value of the neighbors of the polygon and the coefficient of variation are obtained. Here, the coefficient of variation is calculated as a percentage of a value obtained by dividing the standard deviation of the area of the Voronoi polygon by the average value. The reason for adopting the variation coefficient instead of the standard deviation as an index for evaluating the variation of the area of the Voronoi polygon is to evaluate the variation except for the influence of the magnitude of the average value of the area of the Voronoi polygon.

3 is a Voronoi diagram showing an example in which the Voronoi is divided on the surface of the convex portion of the antiglare film at the apex of the antiglare film. A plurality of corner points 26 and 26 having a plurality of corners are apexes of convex portions of the antiglare film and one Voronoi polygon 27 is assigned to one corner point 26 by Voronoi division. In this figure, the Voronoi polygons 28, 28, which are thinly painted, are Voronoi polygons that are in contact with the boundary of the field of view. The Voronoi polygon that is in contact with the boundary of this field of view is not used only when calculating the average value of the area of the Voronoi polygon and the coefficient of variation, since it is not determined only by the apex of the convex portion that is the furthest point. On the other hand, in this figure, it is easily understood from the above description and this drawing that there are a plurality of spots and a Voronoi polygon, although some drawing points and a Voronoi polygon are drawn only to some points and a sign.

The antiglare film of the present invention can be obtained by setting the average value and the variation coefficient of the area of the Voronoi polygon described above to a predetermined range, respectively, by the synergetic effect of the haze described later, the average value and the standard deviation of the inclination angle described above, It exhibits excellent anti-glare properties while satisfactorily preventing occurrence of stuttering. In order to effectively exhibit such an effect, the average value of the area of the Voronoi polygon is set to be not less than 50 μm ^{2 and not} more than 150 μm ² . It is more preferable that the average value of the area is not less than 75 μm ^{2 and not} more than 125 μm ² . For the same reason, the variation coefficient of the area of the Voronoi polygon is set to 40% or more and 80% or less. The coefficient of variation is more preferably 50% or more and 70% or less, and still more preferably 50% or more and 60% or less.

When the average value of the areas of the Voronoi polygons is less than the above range, the convex portions of the micro concavo-convex surface of the antiglare film are arranged in an excessively dense manner, and it is difficult to obtain sufficient diffusibility. On the other hand, when the average value of the areas of the Voronoi polygons exceeds the above-mentioned range, the convex portions of the micro concavo-convex surface of the antiglare film are excessively brittle and flicker occurs when arranged in the image display apparatus.

When the variation coefficient of the area of the Voronoi polygon is less than the above range, the area distribution of the Voronoi polygon is not sufficiently widened, and the arrangement of the convex portions having the intervals of 50 mu m or more is insufficient, It is difficult to obtain the present status. On the other hand, when the variation coefficient of the area of the Voronoi polygon exceeds the above range, the area distribution of the Voronoi polygon becomes excessively wide, so that the arrangement of dense convex portions can not be obtained and flashing occurs.

[Total haze and surface haze]

The antiglare film of the present invention has a total haze in the range of 0.1% or more and 3% or less and a surface haze in a range of 0.1% or more and 2% or less in terms of vertical incidence light in order to exhibit anti- do. The total haze of the antiglare film can be measured in accordance with the method specified in JIS K7136: 2000 " Method of obtaining haze of plastic-transparent material ". An antiglare film having a total haze or a surface haze of less than 0.1% is undesirable because the image display device in which it is disposed does not exhibit sufficient antiglare property. Further, an antiglare film having a total haze of more than 3% or a surface haze of more than 2% is not preferable because the image display device in which the antiglare film is formed causes whitening. Such an image display device also has a problem that its contrast is also insufficient.

The lower the internal haze obtained by subtracting the surface haze from the total haze, the better. An image display device in which an antiglare film having an internal haze of more than 2.5% is disposed has a tendency to lower its contrast.

[Transmission clarity Tc, reflection sharpness Rc (45) and reflection sharpness Rc (60)]

The antiglare film of the present invention preferably has a transmission clearance Tc of 375% or more obtained by the following method. That is, the sum of transmission sharpness Tc can be obtained by measuring the image clarity by the transmission method using an optical comb of a predetermined width by a method defined in JIS K7374: 2007 "Method for obtaining plastic-image clarity" . Specifically, the image clarity by the transmission method was measured using five types of optical combs having a ratio of the shielding portion to the transmitting portion of 1: 1 and widths of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm , And the sum of these values is obtained to be Tc. When the antiglare film having a Tc of less than 375% is arranged in a high-definition image display apparatus, flashing may occur easily. The upper limit of Tc is selected within the range of 500% or less, which is the maximum. However, if the Tc is too large, the image display device easily becomes defective from the front. % Or less.

The antiglare film of the present invention preferably has a reflectance sharpness Rc (45) of 180% or less, more preferably 160% or less, as measured with incident light at an incident angle of 45 °. Like the above Tc, the reflection sharpness Rc (45) is measured by the method specified in JIS K7374: 2007. Here, among the five types of optical combs, the widths of the optical combs are 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm Four types of optical combs are used to measure the image clarity at an incident angle of 45 degrees by reflection method, and the sum of these values is obtained as Rc (45). In JIS, five types of optical combs are defined as described above. All of them are selected or the widths are selected as necessary. However, in the antiglare film defined in the present invention, reflection with the use of an optical comb having a width of 0.125 mm Since the value itself is small and the measurement error becomes large, the sharpness is defined as the reflection sharpness with the sum of the image sharpness measured using the above-mentioned four types of optical combs. When the Rc (45) is 180% or less, the image display device having the antiglare film disposed thereon is preferable because the antireflection property when viewed from the front and in the oblique direction becomes good, and when it is 160% or less, Therefore, it is preferable. The lower limit of the Rc (45) is not particularly limited, but is preferably 80% or more, for example, in order to suppress occurrence of whitening and glare.

Further, the antiglare film of the present invention preferably has a reflectance sharpness Rc (60) of 240% or less, more preferably 220% or less, as measured with incident light at an incident angle of 60 °. The reflection sharpness Rc (60) is measured by a method in accordance with JIS K7374: 2007 which is the same as the above-described reflection sharpness Rc (45) except that the incident angle is changed. When the content of Rc (60) is 240% or less, the image display device provided with the antiglare film is preferable because the antireflection property when observed in the oblique direction becomes good, and when it is 220% or less, the image display device is preferable. The lower limit of the Rc (60) is not particularly limited, but is preferably 150% or more, for example, in order to suppress occurrence of whitening and glare.

[General method for producing antiglare film]

The antiglare film of the present invention is produced, for example, as follows. The first method is a method of preparing a fine unevenness forming mold having a surface relief shape based on a predetermined pattern formed on a molding surface, transferring the shape of the relief surface of the mold to a transparent support, And the support is peeled off from the mold. A second method is a method of preparing a coating film comprising fine particles comprising fine particles, a binder resin and a solvent, preparing a composition in which the fine particles are dispersed in a resin solution, applying the composition onto a transparent support, Curing. In the second method, fine particles are exposed on the surface of the coating film to form random irregularities on the transparent support by adjusting the thickness of the coating film and the coagulation state of the fine particles by the composition of the composition and the drying conditions of the coating film. From the viewpoint of production stability and production reproducibility of the antiglare film, it is preferable to produce the antiglare film of the present invention by the first method.

Here, a first method preferable as a method for producing an antiglare film of the present invention will be described in detail. In order to precisely form the antiglare layer having the surface irregularities having the above-mentioned characteristics, it is important to prepare the fine irregularities forming mold (hereinafter abbreviated as " mold "). More specifically, the surface irregularities (hereinafter sometimes referred to as " metal irregularities ") of the metal mold are formed based on a predetermined pattern, and the predetermined pattern has an average frequency Of not less than 0.075 mu m- ^{1 and not} more than 0.105 mu m- ¹ , and a standard deviation of not less than 0.095 mu m- ^{1 and not} more than 0.125 mu m- ¹ . Here, the term " pattern " means image data for forming the surface irregularities of the antiglare layer of the antiglare film, a mask having the light transmitting portion and the light shielding portion, and the like.

First, a method of determining a pattern for forming the surface relief shape of the antiglare layer of the antiglare film of the present invention will be described.

A method of obtaining the two-dimensional power spectrum of the pattern is described, for example, when the pattern is image data. First, after converting the image data into binary image data of two gradations (gradation), the gradation is represented by a two-dimensional function g (x, y). The two-dimensional function g (f _x , f _y ) obtained by Fourier transforming the obtained two-dimensional function g (x, y) as shown in the following equation (1) (f _x , f _y ) by squaring the absolute value of the two-dimensional power spectrum Γ (f _x , f _y ). Here, x and y represent the Cartesian coordinates in the image data plane. In addition, f _x and f _y represent frequencies in the x and y directions, respectively, and have dimensions of reciprocal of length.

In the equation (1), π is the circularity, i is the imaginary unit, and <g> is the average of the two-dimensional function g (x, y).

The obtained two-dimensional power spectrum Γ (f _x , f _y ) represents the spatial frequency distribution of the pattern. Normally, since the antiglare film is required to be isotropic, the pattern for producing the antiglare film of the present invention becomes isotropic. Therefore, the two-dimensional function Γ (f _x , f _y ) representing the two-dimensional power spectrum of the pattern can be represented by a one-dimensional function Γ (f) depending only on the distance f from the origin (0,0).

Next, a method of obtaining a one-dimensional function Γ (f) from the two-dimensional function Γ (f _x , f _y ) will be described. First, a two-dimensional function Γ (f _x , f _y ), which is a two-dimensional power spectrum of the gradation of a pattern, is expressed in polar coordinates as shown in the following equation (3).

Here,? Is a declination angle in the Fourier space. The one-dimensional function Γ (f) can be obtained by calculating the rotation average of the two-dimensional function Γ (fcosθ, fsinθ) expressed in polar coordinates by the following equation (4). Dimensional function Γ (f) obtained from the rotation average of the two-dimensional function Γ (f _x , f _y ) which is the two-dimensional power spectrum of the gradation of the pattern is also referred to as a one-dimensional power spectrum Γ (f).

In order to obtain an anti-glare film of the present invention with high accuracy, the average frequency calculated from the one-dimensional power spectrum of the pattern <f> is 0.075 ㎛ ^-1 than 0.105 ㎛ ^-1 or less, and the standard deviation σ _f is 0.095 ㎛ ^-1 than 0.125 ㎛ ^{- 1} or less. Here, the average frequency &lt; f &gt; and the standard deviation [sigma] _f calculated from the one-dimensional power spectrum of the pattern are defined by the following equations (5) and (6), respectively.

When the two-dimensional power spectrum of the pattern is obtained, the two-dimensional function g (x, y) of the gradation is usually obtained as a discrete function. In this case, the two-dimensional power spectrum may be calculated by discrete Fourier transform. The one-dimensional power spectrum of the pattern is obtained from the two-dimensional power spectrum of the pattern in the same manner.

The average value of the two-dimensional function g (x, y) is determined by the maximum value of the two-dimensional function g (x, y) and the minimum value of the two-dimensional function g (x, y) To 30% of the difference of the difference. In the case where the surface of the mold concavity and convexity is manufactured by the lithography method, this two-dimensional function g (x, y) is the aperture ratio of the pattern. In the case where the surface of the mold concavity and convexity is manufactured by the lithography method, the aperture ratio of the pattern described here is defined. The aperture ratio when the resist used in the lithography method is a positive type means the ratio of the exposed area to the entire surface area of the coated film when image data is drawn on the coated film of the positive resist. On the other hand, the aperture ratio in the case where the resist used for the lithography method is of the negative type means the ratio of the unexposed area to the entire surface area of the coating film when the image data is drawn on the coating film of the negative resist. The aperture ratio when the lithography method is a batch exposure means the ratio of the transparent portion of the mask having the transparent portion and the shielding portion.

The antiglare film of the present invention is produced by preparing a desired mold by setting the average frequency &lt; f &gt; and the standard deviation? _F calculated from the one-dimensional power spectrum of the pattern to the above-mentioned ranges, Can be manufactured.

In order to generate a pattern of one-dimensional power spectrum having such an intensity ratio, a pattern (random pattern) prepared by randomly arranging dots or a pattern having a random brightness distribution determined by a random number or a similar random number generated by a calculator And a component in a specific spatial frequency range is removed from the preliminary pattern. In removing the component of the specific spatial frequency range, the preliminary pattern may be passed through the band-pass filter.

In order to produce an antiglare film having an antiglare layer provided with a surface relief shape based on a predetermined pattern, a mold having a relief surface for transferring a surface relief shape formed on the basis of the predetermined pattern to a transparent support is produced. The first method using such a mold is an embossing method in which an antiglare layer is formed on a transparent support.

The emboss method is further classified into an optical emboss method using a photo-curable resin, a hot emboss method using a thermoplastic resin, and the like. Among them, the optical embossing method is preferable from the viewpoint of productivity.

The photomasking method is a method in which a photocurable resin layer is formed on a transparent support (a surface of a transparent support), and the photocurable resin layer is cured while pressing the photocurable resin layer against the surface of the mold, . Specifically, in the state that the photo-curable resin layer formed by applying the photo-curing resin on the transparent support is in close contact with the surface of the metal mold, light is irradiated from the transparent support side (this light indicates that the photo- Is used to cure the photocurable resin layer, and then the transparent support on which the hardened layer of the photocurable resin is formed is peeled from the mold. In the antiglare film obtained by this method, the cured layer of the photocurable resin becomes the antiglare layer. On the other hand, from the viewpoint of ease of manufacture, an ultraviolet ray-curable resin is preferable as the photo-curing resin, and ultraviolet rays are used as the light to be irradiated when this ultraviolet ray-curable resin is used. The embossing method using an ultraviolet curable resin as the photo-curing resin is hereinafter referred to as &quot; UV embossing method &quot;. In order to produce an antiglare film integrated with a polarizing film, a polarizing film may be used as the transparent support, and the transparent support may be replaced with a polarizing film in the embossing method described herein.

The type of ultraviolet-curable resin used in the UV embossing method is not particularly limited, and among commercially available resins, an appropriate one may be used depending on the kind of the transparent support and the kind of ultraviolet ray. The ultraviolet ray curable resin referred to here is a concept including a monomer (multifunctional monomer), an oligomer and a polymer which are photopolymerized by ultraviolet irradiation, and a mixture thereof. A resin capable of curing even visible light having a wavelength longer than that of ultraviolet rays may be used by suitably using a photoinitiator selected in accordance with the type of the ultraviolet curable resin. Suitable examples of the ultraviolet-setting resin will be described later.

Examples of the transparent support used in the UV embossing method include glass and plastic film. Plastic films can be used if they have adequate transparency and mechanical strength. Specifically, for example, a cellulose acetate-based resin such as triacetylcellulose; Acrylic resin; Polycarbonate resin; Polyester-based resins such as polyethylene terephthalate; And a transparent resin film made of a polyolefin-based resin such as polyethylene or polypropylene. These transparent resin films may be solvent cast films or extruded films.

The thickness of the transparent support is, for example, 10 to 500 占 퐉, preferably 10 to 100 占 퐉, and more preferably 10 to 60 占 퐉. If the thickness of the transparent support is within this range, an antiglare film having sufficient mechanical strength tends to be obtained, and the image display apparatus provided with the antiglare film is less likely to flicker.

On the other hand, the hot emboss method is a method in which a transparent resin film formed of a thermoplastic resin is heated and softened in a state softened, and the surface unevenness shape of the mold is transferred to a transparent resin film. The transparent resin film used in the hot embossing method may be any film as long as it is substantially optically transparent. Specifically, the transparent resin film used in the UV embossing method may be those exemplified above.

[Manufacturing Method of Mold]

Next, a method of manufacturing a mold used in the embossing method will be described. With respect to the manufacturing method of the mold, it is preferable that the mold surface of the mold is formed so as to be capable of transferring the surface irregularities formed on the basis of the above-mentioned predetermined pattern onto the transparent support (forming the antiglare layer having the surface irregularities formed on the basis of the predetermined pattern , The lithography method is preferable in order to manufacture the antiglare layer of the surface relief shape with high precision and high reproducibility. The lithography method may further include the steps of [1] a first plating step, [2] a first polishing step, [3] a photosensitive resin film forming step, [4] an exposure step, [5] It is preferable that the process includes the steps of [7] photosensitive resin film peeling step, [8] second etching step, [9] second plating step, and [10] protective film forming step.

5 is a diagram schematically showing a preferable example of the first half of the method for manufacturing a mold (up to the developing step of the above-mentioned [5]). This figure schematically shows a cross section of a mold in each step. Hereinafter, with reference to Fig. 5, each step of the method for producing a mold for producing an antiglare film will be described in detail.

[1] First plating process

First, a substrate (substrate for a mold) used for manufacturing a mold is prepared, and the surface of the substrate for a mold is plated with copper. As described above, by performing copper plating on the surface of the mold base material, the adhesion and gloss of the nickel plating in the second plating step described later can be improved. Copper plating has a high covering property and a high smoothing action, so that it is possible to form a smooth and glossy surface by filling minute concavities and convexities of a base material for a mold. Therefore, by performing copper plating on the surface of the mold base material in this manner, after the nickel plating is performed in the second plating process to be described later, the surface roughness that may be caused by minute irregularities and holes existing in the base material is eliminated do. Therefore, after the surface irregularity shape (fine irregular surface shape) based on the predetermined pattern is formed on the mold base material molding surface, it is possible to sufficiently prevent the deviation due to the influence of the surface of the base (base material) .

Copper used for copper plating in the first plating process may be a pure metal of copper or an alloy (copper alloy) containing copper as a main component. Therefore, &quot; copper &quot; used for copper plating is a concept including copper and a copper alloy. Copper plating may be either electrolytic plating or electroless plating, but it is preferable to use electrolytic plating for copper plating in the first plating step. The preferable plating layer in the first plating step may be not only a copper plating layer but also a copper plating layer and a plating layer made of a metal other than copper.

If the plating layer formed by copper plating on the surface of the mold base material is too thin, the influence of the base surface (minute unevenness, holes, cracks, etc.) can not be excluded. Although the upper limit of the thickness of the plating layer is not critical, it is preferably about 500 탆 or less in consideration of cost and the like.

The substrate for a mold is a metal material, but from the viewpoint of cost, aluminum, iron, or the like is preferable as a material of the metal material. From the viewpoint of handling convenience of the mold base material, a base material made of lightweight aluminum is particularly preferable as a mold base material. On the other hand, the aluminum or the iron mentioned here is not necessarily a pure metal, and may be an alloy containing aluminum or iron as a main component.

The shape of the base material for the mold may be any suitable one in accordance with the production method of the antiglare film. Specifically, it is selected from a plate-like base material, a columnar or cylindrical (roll-shaped) base material, and the like. When the antiglare film is continuously produced, it is preferable that the mold is roll-shaped. Such a mold is made of a roll-shaped mold base material.

[2] First polishing step

In the subsequent first polishing step, the surface (plating layer) of the substrate for copper plating is polished in the first plating step described above. In the production of a mold for use in the production of an antiglare film, it is preferable that the surface of the mold base is polished to a state close to the mirror surface through the first polishing step. In the case of a flat plate substrate or a roll-shaped substrate commercially available as a substrate for a metal mold, machining such as cutting or grinding is frequently performed in order to obtain a desired precision, and thus fine processing marks remain on the surface. Therefore, even if the copper plating layer is formed by the first plating step, the above-mentioned processing mark may remain. Further, even if copper plating is performed in the first plating step, the surface of the mold base material is not completely smoothed. That is, even if the steps of [3] to [10] to be described later are carried out on a substrate for a mold having such a deep processing mark left on its surface, the concavo-convex shape of the obtained mold surface may be different from that of a predetermined pattern, Or unevenness originating in the land may be included. When an antiglare film is produced by using a mold in which the influence of a machining station or the like remains, there is a fear that optical characteristics such as a desired antiglare property are not sufficiently manifested and an unexpected influence is exerted.

The polishing method to be applied in the first polishing step is not particularly limited, and a method according to the shape and properties of the substrate for polishing to be polished is selected. Specific examples of the polishing method applicable to the first polishing step include mechanical polishing, electrolytic polishing, and chemical polishing. Of these, in the mechanical polishing, any of super finishing method, lapping method, fluid polishing method, and buff polishing method can be used. Further, the surface of the mold base may be mirror-finished by mirror-cutting using a cutting tool in the polishing step. The cutting tool in this case can be a cemented carbide, a CBN, a ceramic, a diamond, or the like depending on the material (the kind of the metal material) of the mold base material. The surface roughness after polishing is represented by a center line average roughness (Ra) according to JIS B0601: 2013 &quot; Geometric Property Specification (GPS) - Surface Property: Contour Curve Method - Terms, Definitions and Surface Property Parameters &quot; More preferably 0.05 mu m or less. If the center line average roughness (Ra) after polishing is larger than 0.1 占 퐉, the surface roughness of the finally obtained mold surface may be influenced by the surface roughness. The lower limit of the center line average roughness Ra is not particularly limited, and the lower limit may be set in view of the processing time (polishing time) and the processing cost in the first polishing step.

[3] Photosensitive resin film forming process

Next, the photosensitive resin film forming step will be described with reference to Fig. 5A shows a state in which the surface of the mold base material 40 is polished and plated through the first plating step and the first polishing step. In the step of forming a photosensitive resin film, a solution (photosensitive resin solution) in which a photosensitive resin is dissolved in a solvent is applied to the polished surface 41 of the mold base material 40 obtained by the above-described first polishing step, Thereby forming a photosensitive resin film (resist film). Fig. 5B schematically shows a state in which the photosensitive resin film 50 is formed on the polished surface 41 of the mold base material 40. Fig.

As the photosensitive resin, conventionally known ones can be used, and those commercially available as resists can be used as they are, or they can be purified after filtration if necessary. Examples of the negative-type photosensitive resin having a property of curing the photosensitive portion include monomers and prepolymers of (meth) acrylic acid esters having acryloyl groups or methacryloyl groups in the molecule, mixtures of bisazides and diene rubbers, Vinyl cinnamate-based compounds, and the like. As the positive photosensitive resin having the property that the photosensitive portion is eluted by the development and only the non-photosensitive portion remains, a phenol resin-based nano-bloc resin-based resin or the like can be used. Such a positive or negative photosensitive resin can be easily obtained as a positive resist or a negative resist on the market. The photosensitive resin solution may be blended with various additives such as a sensitizer, a development promoter, an adhesion modifier, and a coating property improving agent as necessary, and a mixture of such additives in a commercially available resist may be used as a photosensitive resin solution .

In order to apply these photosensitive resin solutions to the polished plated surface 41 of the mold base material 40, an optimal solvent for forming a smooth photosensitive resin film is selected, and the photosensitive resin is dissolved and diluted in such a solvent It is preferable to use the obtained photosensitive resin solution. Such a solvent is selected depending on the kind of the photosensitive resin and its solubility. Specifically, it is selected from a cellosolve solvent, a propylene glycol solvent, an ester solvent, an alcohol solvent, a ketone solvent, a high polar solvent, and the like. When a commercially available resist is used, an optimum resist may be selected and used as a photosensitive resin solution, depending on the type of the solvent contained in the resist or a suitable preliminary experiment.

The method of applying the photosensitive resin solution to the polished plated surface 41 of the mold base material may be a method of applying the photosensitive resin solution to the polished plated surface 41 of the mold base by a method such as meniscus coat, fountain coat, dip coat, spin coating, roll coating, wire bar coating, air knife coating, , A ring coat, and the like, depending on the shape of the mold base material and the like. The thickness of the photosensitive resin film after application is preferably in the range of 1 to 10 mu m after drying, more preferably in the range of 6 to 9 mu m.

[4] Exposure Process

The subsequent exposure step is a step of transferring the pattern to the photosensitive resin film 50 by exposing the intended pattern to the photosensitive resin film 50 formed in the photosensitive resin film forming step described above. The light source used in the exposure process may be suitably selected in accordance with the photosensitive wavelength and the sensitivity of the photosensitive resin included in the photosensitive resin film. For example, a g line (wavelength: 436 nm), h line (wavelength: 405 nm) (Wavelength: 830 nm, 532 nm, 488 nm, 405 nm), YAG laser (wavelength: 1064 nm), KrF excimer laser (wavelength: 248 nm), ArF excimer Laser (wavelength: 193 nm), F2 excimer laser (wavelength: 157 nm), or the like can be used. The exposure method may be a method of collective exposure using a mask corresponding to a target pattern, or a drawing method. The aimed pattern means that the mean frequency &lt; f &gt; and the standard deviation? _F calculated from the one-dimensional power spectrum of the pattern are within a predetermined preferable range, respectively, as described above.

In manufacturing the mold, it is preferable to expose the desired pattern on the photosensitive resin film 50 in a precisely controlled state in order to form the surface relief shape of the mold with high precision. In order to expose in such a state, a desired pattern on a computer is created as image data, and a pattern based on the image data is drawn (laser drawn) on the photosensitive resin film by laser light emitted from a computer-controlled laser head . For laser imaging, for example, a device commonly used in the production of a printing plate can be used. As a commercially available product of such a laser beam drawing apparatus, for example, Laser Stream FX (manufactured by Synlaboratori) can be mentioned.

Fig. 5 (c) schematically shows a state in which the pattern is exposed on the photosensitive resin film 50 in Fig. 5 (b). When a negative photosensitive resin is contained in the photosensitive resin film 50 (specifically, when a negative type resist is used as the photosensitive resin solution), the exposed region 51 is exposed to exposure energy to perform a crosslinking reaction of the photosensitive resin And the solubility in a developer to be described later decreases. Thus, the unexposed area 52 is dissolved in the developing solution in the developing step, and only the exposed area 51 remains on the surface of the substrate to become the mask 60 (refer to FIG. 5 (d)). On the other hand, in the case where a positive photosensitive resin is contained in the photosensitive resin film 50 (specifically, when a positive type resist is used as the photosensitive resin solution), the exposed region 51 is exposed to the exposure energy, By breaking the bond, it becomes easy to dissolve in a developer to be described later. Thus, the exposed area 51 is dissolved in the developing solution in the developing process, and only the unexposed area 52 remains on the surface of the substrate to become the mask 60.

[5] Development process

In the developing step, when the photosensitive resin film 50 contains a negative-type photosensitive resin, the unexposed area 52 is dissolved in the developing solution, the exposed area 51 remains on the mold base, The mask 60 is formed. On the other hand, when the photosensitive resin film 50 contains a positive photosensitive resin, the exposed area 51 is dissolved in the developing solution, the unexposed area 52 remains on the substrate for the mask, 60). In the substrate for a mold in which a predetermined pattern is formed as a photosensitive resin film, the photosensitive resin film remaining on the substrate for a mold acts as a mask in a first etching step to be described later.

With regard to the developer used in the developing process, among those conventionally known, those suitable for the type of the photosensitive resin used can be selected. Examples of the developer include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; Primary amines such as ethylamine, n-propylamine; Secondary amines such as diethylamine, di-n-butylamine; Tertiary amines such as triethylamine and methyldiethylamine; Alcohol amines such as dimethylethanolamine and triethanolamine; Quaternary ammonium compounds such as tetramethylammonium hydroxide, tetraethylammonium hydroxide and trimethylhydroxyethylammonium hydroxide; An alkaline aqueous solution in which cyclic amines such as pyrrole and piperidine are dissolved; And organic solvents such as xylene and toluene.

The developing method in the developing step is not particularly limited, and an immersion phenomenon, a spray phenomenon, a brush phenomenon, an ultrasonic phenomenon, or the like can be used.

Fig. 5 (d) schematically shows a state after the development step is performed by using a photosensitive resin as a negative type. The unexposed area 52 is dissolved in the developing solution and only the exposed area 51 remains on the surface of the substrate so that the photosensitive resin film in this area is the mask 60 shown in FIG. do. Fig. 5 (e) schematically shows a state after the development step is performed by using a photosensitive resin as a positive type. The exposed area 51 is dissolved in the developing solution and only the unexposed area 52 remains on the surface of the substrate so that the photosensitive resin film in this area is exposed to the mask 60 shown in FIG. do.

[6] First etching step

The first etching step is a step of etching the plating layer in the mask-free area of the surface of the mold base using the photosensitive resin film remaining on the surface of the mold base after the above-described development process as a mask.

6 is a diagram schematically showing a preferred example of the second half of the method for manufacturing a mold (after the first etching step of the above-mentioned [6]). Fig. 6 (a) schematically shows a state after the plating layer in the maskless region is etched mainly by the etching step. The plating layer under the mask 60 is not etched because the photosensitive resin film functions as the mask 60, but the etching proceeds from the maskless region 45 with the progress of the etching. Therefore, the plating layer under the mask 60 is also etched near the boundary between the region where the mask 60 is present and the region without the mask 45. In this manner, the plating layer under the mask 60 is also etched at the vicinity of the boundary between the region where the mask 60 is present and the region without the mask 45, which is referred to as side etching.

The etching treatment in the first etching step is usually carried out by using an etching solution such as an aqueous solution of ferric chloride (FeCl ₃ ), an aqueous solution of cupric chloride (CuCl ₂ ), an alkali etching solution (Cu (NH ₃ ) ₄ Cl ₂ ) (Metal surface) in a region where the mask 60 is not present, among the surface of the mold base material. In this etching treatment, a strong acid such as hydrochloric acid or sulfuric acid may be used as an etching solution. In the case where the first plating step is performed by electrolytic plating, an inverse electrolytic etching with a potential opposite to that at electrolytic plating may be employed. Since the surface irregularities formed on the mold base material by performing the etching treatment depend on the constituent material (metal material) of the mold base material, the kind of the plated layer, the type of the photosensitive resin film, and the type of the etching treatment in the etching process, When the etching amount is not more than 10 탆, it is etched from the surface of the substrate for forming the mold in contact with the etching solution in a substantially isotropic manner. The etching amount referred to here is the thickness of the plating layer cut by etching.

The etching amount in the first etching step is preferably 1 to 20 占 퐉, more preferably 3 to 12 占 퐉, and still more preferably 5 to 8 占 퐉. When the etching amount is less than 1 占 퐉, the surface irregularities are hardly formed on the metal mold and have a substantially flat surface. Therefore, even when the antiglare film is produced by using the metal mold, In an image display device having such an antiglare film, the film is not sufficiently deflected. In addition, when the etching amount is excessively large, the concave-convex surface of the finally obtained mold tends to have a large difference in height. When an antiglare film produced from such a mold is applied to an image display apparatus, the occurrence of whitening can not be sufficiently prevented. The etching process may be performed by one etching process or may be divided into two or more etching processes. In the case where the etching treatment is divided into two or more times, it is preferable that the sum of the etching amounts in two or more etching treatments is 1 to 20 占 퐉.

[7] Photosensitive resin film peeling step

The subsequent photosensitive resin film peeling step is a step of acting as a mask 60 in the first etching step to remove the photosensitive resin film remaining on the substrate for a mold. In this step, the photosensitive resin film remaining on the substrate for the mold is completely removed . In the photosensitive resin film peeling step, it is preferable to dissolve the photosensitive resin film using a peeling liquid. As the exfoliation liquid, those exemplified as the developer can be used by changing the concentration, pH, and the like. Alternatively, the same developer as that used in the developing process may be used, and the photosensitive resin film may be peeled off by changing the temperature or immersion time with the developing process. In the photosensitive resin film peeling step, a method of contacting the peeling liquid with the substrate for the mold (peeling method) is not particularly limited, and the peeling may be peeling off, spray peeling, brush peeling, ultrasonic peeling or the like.

6 (b) schematically shows a state in which the photosensitive resin film used as the mask 60 in the first etching step is completely dissolved and removed in the photosensitive resin film peeling step. The first surface irregularities 46 are formed on the surface of the mold base material by the mask 60 and the etching treatment with the photosensitive resin film.

[8] Second etching process

The second etching step is a step for further reducing the first surface irregularities 46 formed in the first etching step by the etching treatment (second etching treatment). By this second etching treatment, there is no part of the first surface relief shape 46 formed in the first etching treatment, where the surface inclination is steeply inclined (hereinafter referred to as &quot; surface irregularity shape &quot; Is referred to as &quot; shape slowing &quot;). 6 (c) shows a state in which the first surface concave-convex shape 46 of the mold base material 40 is reduced in shape by the second etching treatment, so that the portion of the surface inclination having a steep slope is reduced, There is shown a state in which the surface relief shapes 47 are formed. As described above, the mold obtained by reducing the shape by the second etching treatment has an effect of making the optical characteristics of the antiglare film produced using the mold more preferable.

Also in the second etching step, an etching process using an etching liquid such as the first etching process or an inverse electrolytic etching process can be used. The degree of the shape reduction after the second etching treatment (degree of disappearance of the portion where the surface inclination is steep in the surface irregular shape after the first etching step) is determined by the material of the mold base material, the means of the second etching treatment, The size and depth of the concavities and convexities in the surface irregularities obtained by the first etching treatment, and the like. However, the greatest factor in controlling the slowing state (degree of shape reduction) is etching . The amount of etching referred to here is also expressed by the thickness of the substrate shaved by the second etching treatment, as in the case of the first etching step. If the etching amount of the second etching process is small, the effect on the shape reduction of the surface irregularity shape obtained by the first etching process becomes insufficient. Therefore, in the antiglare film produced using a mold with insufficient shape reduction, the average value and the standard deviation of the inclination angles of the surface irregularities tend to exceed the range specified in the present invention, resulting in the occurrence of whitening have. On the other hand, if the etching amount in the second etching process is excessively large, the surface irregularities formed by the first etching process are almost lost, and a mold having a substantially flat surface may be formed. The antiglare film produced using such a mold having an almost flat surface has a problem in that the average value and standard deviation of the inclination angles of the surface irregularities tend to fall short of the range specified in the present invention and as a result, There are many. Therefore, the etching amount in the second etching treatment is preferably in the range of 1 to 50 mu m, further more preferably in the range of 4 to 20 mu m, particularly preferably in the range of 9 to 12 mu m. The second etching step may be performed by one etching treatment or may be divided into two or more etching steps similarly to the first etching step. When the etching treatment is divided into two or more times, it is preferable that the total etching amount in two or more etching treatments is in the range of 1 to 50 mu m.

[9] Second plating process

In the second plating step, on the surface of the substrate for a mold which has undergone the above-mentioned [6] first etching step and [7] photosensitive resin film peeling step, preferably the above-mentioned [8] second etching step, Preferably, glossy nickel plating described later) is performed. By performing the second plating process, the surface irregularities 47 of the mold base material can be further reduced, and the surface of the mold can be protected by the plating. 6 (d), the nickel plating layer 71 is formed on the second surface irregular surface 47 formed by the second etching treatment as described above, so that the surface irregularities are reduced in shape, As shown in Fig.

The plating layer formed in the second plating step is preferably made of nickel plating which is glossy and has excellent corrosion resistance. Among nickel plating, nickel plating which is called glossy nickel plating or the like and which exhibits good gloss is particularly preferable. The nickel plating may be performed by electrolytic plating or electroless plating. When electrolytic plating is employed, an aqueous solution containing nickel sulfate, nickel chloride and boric acid is preferably used as the plating bath. By controlling the current density and the electrolysis time, the thickness of the nickel plating layer can be controlled. When electroless plating is employed, examples of the plating bath include nickel salts (nickel sulfate, nickel chloride, nickel carbonate, nickel acetate, nickel sulfite, nickel hypophosphite, etc.), reducing agents (hypophosphorous acid, sodium hypophosphite, potassium hypophosphite (Aminic compounds such as ethylenediamine, glycolic acid, lactic acid, gluconic acid, propionic acid and the like), and the like, , Tricarboxylic acids such as tartaric acid, malic acid, succinic acid and malonic acid, tricarboxylic acids such as citric acid and the like, or carboxylic acid salts such as sodium salts, potassium salts and ammonium salts of these carboxylic acids, stabilizers (Pb, Bi , Heavy metal stabilizers such as Tl, In and Sn; and organic stabilizers such as propargyl alcohol, thioether compounds, thiocyanic compounds, thionic acid, and titanates) are preferably used. The thickness of the nickel plating layer can be controlled by controlling the concentration, temperature, and processing time of the plating liquid.

By performing nickel plating on the concave-convex shape on the surface of the mold base material after the second etching treatment, it is possible to further reduce the shape and obtain a mold with increased surface hardness. The largest factor in controlling the degree of shape reduction in this case is the thickness of the nickel plated layer. If the nickel plating layer is thin, the degree of shape reduction becomes insufficient, and the antiglare film obtained from such a mold may cause whitening. On the other hand, if the nickel plating layer is too thick, the antireflection property becomes insufficient. It has been found that it is effective to manufacture a mold such that the thickness of the nickel plating layer is within a predetermined range in order to sufficiently prevent occurrence of whitening and to provide an antiglare film to give an image display device having excellent antiglare property. That is, the thickness of the nickel plating layer is preferably in the range of 2 to 12 占 퐉, more preferably in the range of 5 to 10 占 퐉.

[10] Protective Coating Process

The last step of the mold production is a protective film forming step of forming a protective film on the surface (nickel plating layer) of the base material for nickel which is subjected to nickel plating in the second plating step. Nickel plating is glossy and has excellent corrosion resistance. However, since hardness is not sufficient, if the antiglare film is continuously produced as it is, there is a possibility that the surface is worn or damaged. Thus, it is preferable to form a protective coating film on the nickel plating, which has a high hardness, a small coefficient of friction, and a good releasability by providing a protective film forming process.

The film formed in the protective film forming step is preferably a carbon film, and examples thereof include a diamond thin film, a diamond-like carbon film, a hydrogenated amorphous carbon film (also called a DLC film by reducing a diamond like carbon film) and the like. The diamond-like carbon film and the DLC film can be formed by a plasma CVD method, an ion beam method, or the like by a microwave plasma CVD method, a hot filament CVD method, a plasma jet method, an ECR plasma CVD method, A sputtering method, an ion beam deposition method, a plasma sputtering method, or the like. IBM (Ion Beam Mixing) for injecting at least one kind of ion selected from an inert gas, nitrogen and carbon at the same time as forming the carbon film, or PBII (Plasma Based Ion Implantation) for applying a pulse bias to the substrate for injection, It is possible to eliminate the clear interface between the film and the mold base material and improve the adhesion. The thickness of these carbon films is preferably in the range of 0.1 to 5 mu m, more preferably in the range of 0.5 to 3 mu m. If the carbon film is too thin, there is a possibility that the durability as a mold becomes insufficient. On the other hand, if the carbon film is excessively thick, the productivity is deteriorated, which is not preferable.

[Production of antiglare film using mold]

Hereinafter, the above-described optical embossing method which is preferable as a method for producing the antiglare film of the present invention will be described. As described above, the UV embossing method is particularly preferable as the optical embossing method. Here, the embossing method using the active energy ray-curable resin will be described in detail.

When the antiglare film is continuously produced by the optical embossing method, it is preferable that at least the coating process of [P1] and the final curing process of [P3] are provided in this order among the following processes. Further, it is more preferable to provide a preliminary curing step of [P2] between the both steps.

[P1] A coating process for coating a coating liquid containing an active energy ray-curable resin on a transparent support continuously transported to form a coating layer,

[P2] a preliminary curing step of irradiating an active energy ray to both end regions in the width direction of the coating layer formed in the coating step, and

[P3] The main curing step of irradiating the active energy ray on the surface of the coating layer while the surface of the mold is closely attached.

Hereinafter, each step will be described in detail with reference to the drawings. 7 is a diagram schematically showing an arrangement example of a device suitably used in the case of continuously producing an antiglare film. 7, the straight arrows indicate the transport direction of the film, and the curved arrows indicate the rotation direction of the roll.

[P1] Coating process

In the coating step, a coating liquid containing an active energy ray-curable resin is coated on a transparent support to form a coating layer. In the coating step, as shown in Fig. 7, a coating liquid containing an active energy ray-curable resin is applied to the transparent support 81, which is unwound from the delivery roll 80, in the coating zone 83. [

The application of the coating liquid onto the transparent support 81 can be carried out, for example, by a gravure coating method, a micro gravure coating method, a rod coating method, a knife coating method, an air knife coating method, a kiss coating method, have.

(Transparent support)

The transparent support 81 may be of any type as long as it is transmissive. For example, glass or plastic film can be used. The plastic film may have appropriate transparency and mechanical strength. Specifically, any of those exemplified as the transparent support used in the UV embossing method may be used first, and in order to continuously produce an antiglare film by the optical embossing method, those having suitable flexibility are selected.

Various surface treatments may be applied to the surface of the transparent support 81 (the surface to which the coating liquid is applied) for the purpose of improving the coating property and improving the adhesion between the transparent support and the coating layer. Examples of the surface treatment include a corona discharge treatment, a glow discharge treatment, an acid surface treatment, an alkali surface treatment, and an ultraviolet ray irradiation treatment. Further, another layer such as a primer layer may be formed on the transparent support 81, and the coating solution may be coated on the other layer.

In order to improve the adhesion between the transparent support and the polarizing film, it is preferable that the surface of the transparent support (the side opposite to the side to which the coating liquid is applied Is preferably hydrophilized by various surface treatments. This surface treatment may be carried out after the production of the antiglare film.

(Coating solution)

The coating liquid contains an active energy ray curable resin and usually contains a photopolymerization initiator (radical polymerization initiator). If necessary, various additives such as a light-transmitting fine particle, a solvent such as an organic solvent, a leveling agent, a dispersing agent, an antistatic agent, an antifouling agent and a surfactant may be contained.

(1) Active energy ray curable resin

As the active energy ray-curable resin, for example, a resin containing a polyfunctional (meth) acrylate compound can be preferably used. The polyfunctional (meth) acrylate compound is a compound having at least two (meth) acryloyloxy groups in the molecule. Specific examples of the polyfunctional (meth) acrylate compound include ester compounds of polyhydric alcohol and (meth) acrylic acid, urethane (meth) acrylate compounds, polyester (meth) acrylate compounds, epoxy (meth) .

Examples of polyhydric alcohols used in the formation of the ester compound include polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, Diols such as glycols, propanediol, butanediol, pentanediol, hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, 2,2'-thiodiethanol and 1,4-cyclohexanedimethanol ; Trimethylol propane, glycerol, pentaerythritol, diglycerol, dipentaerythritol, ditrimethylol propane and the like.

Specific examples of the ester compound between a polyhydric alcohol and (meth) acrylic acid include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,6-hexane diol di (meth) (Meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, trimethylol propane tri (Meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate and the like.

The urethane (meth) acrylate compound may be a urethane reaction product of a polyisocyanate having a plurality of isocyanate groups (-N═C═O) in one molecule and a (meth) acrylic acid derivative having a hydroxyl group. Examples of the polyisocyanate having a plurality of isocyanate groups in a molecule include hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, naphthalene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, dicyclohexylmethane diisocyanate, etc. A diisocyanate having two isocyanate groups in the molecule, and a triisocyanate having three isocyanate groups in a molecule in which isocyanurate-modified, adduct-modified or biuret-modified diisocyanates are included. Examples of the (meth) acrylic acid derivative having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, ) Acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, and pentaerythritol tri (meth) acrylate.

Preferred as the polyester (meth) acrylate compound is a compound obtained by reacting a hydroxyl group-containing polyester with (meth) acrylic acid. The hydroxyl group-containing polyester which is preferably used is a compound obtained by an esterification reaction of a polyhydric alcohol with a compound having a carboxylic acid or a plurality of carboxyl groups and / or anhydride thereof. As the polyhydric alcohol, the same compounds as the above-mentioned compounds can be exemplified. In addition to polyhydric alcohols, polyhydric phenols such as bisphenol A can also be used. Examples of the carboxylic acid include formic acid, acetic acid, butylcarboxylic acid, and benzoic acid. Examples of the compounds having a plurality of carboxyl groups and / or anhydrides thereof include maleic acid, phthalic acid, fumaric acid, itaconic acid, adipic acid, terephthalic acid, maleic anhydride, phthalic anhydride, trimellitic acid and cyclohexanedicarboxylic acid anhydride. .

Among the above-mentioned polyfunctional (meth) acrylate compounds, hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate and diethylene glycol di (meth) acrylate are preferable from the viewpoints of improvement in strength of the cured product, Ester compounds such as trimethylolpropane tri (meth) acrylate, tripropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate and dipentaerythritol hexa (meth) acrylate; Adducts of hexamethylene diisocyanate and 2-hydroxyethyl (meth) acrylate, adducts of isophorone diisocyanate and 2-hydroxyethyl (meth) acrylate, adducts of tolylene diisocyanate and 2-hydroxyethyl (Meth) acrylate, an adduct of adduct-modified isophorone diisocyanate with 2-hydroxyethyl (meth) acrylate, an adduct of adduct of biuret-modified isophorone diisocyanate and 2-hydroxyethyl (Meth) acrylate compounds such as adduct of urethane (meth) acrylate are preferable. These polyfunctional (meth) acrylate compounds may be used alone or in combination of two or more.

The active energy ray-curable resin may contain, in addition to the above-mentioned polyfunctional (meth) acrylate compound, a monofunctional compound having only one polymerizable carbon-carbon double bond in one molecule. Specific examples of the monofunctional (meth) acrylate compound include monofunctional compounds such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxybutyl (Meth) acrylate, 3-methoxybutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethoxyethyl (Meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, glycidyl (meth) acrylate, tetrahydrofurfuryl Acrylate, phenoxyethyl (meth) acrylate, (Meth) acrylate, propylene oxide modified phenoxy (meth) acrylate, nonylphenol (meth) acrylate, ethylene oxide modified nonylphenol (meth) acrylate, propylene oxide modified nonylphenol Acrylate, methoxydiethylene glycol (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, dimethylaminoethyl (meth) acrylate, methoxy triethylene glycol . Further, acryloylmorpholine, N-vinylpyrrolidone and the like can also be monofunctional compounds. These monofunctional compounds may be used alone or in combination of two or more.

The active energy ray curable resin may contain a polymerizable oligomer. By containing a polymerizable oligomer, the hardness of the cured product can be adjusted. Examples of the polymerizable oligomer include a polyfunctional (meth) acrylate compound such as an ester compound of a polyhydric alcohol and (meth) acrylic acid, a urethane (meth) acrylate compound, a polyester (meth) (Meth) acrylate, dimer, trimer, and the like.

Examples of other polymerizable oligomers include urethane (meth) acrylate oligomers obtained by reacting a polyisocyanate having at least two isocyanate groups in a molecule with a compound having at least one (meth) acryloyloxy group and a hydroxyl group . Examples of the polyisocyanate to be used for this purpose include hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate and the like, and at least one (meth) acryloyloxy group and The compound having a hydroxyl group is a hydroxyl group-containing (meth) acrylic acid ester obtained by an esterification reaction between a polyhydric alcohol and (meth) acrylic acid, and a part of the alcoholic hydroxyl group of the polyhydric alcohol is esterified with (meth) acrylic acid, A part of the alcoholic hydroxyl group remains in the molecule. Examples of the polyhydric alcohol to be used herein include polyhydric alcohols such as 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, neopentyl glycol, polyethylene glycol, polypropylene glycol, Glycerol, pentaerythritol, dipentaerythritol, and the like.

Examples of other polymerizable oligomers include polyester (meth) acrylates obtained by reacting a compound having a plurality of carboxyl groups and / or an anhydride thereof with a compound having at least one (meth) acryloyloxy group and a hydroxyl group, Acrylate oligomers. Examples of the compounds having a plurality of carboxyl groups and / or anhydrides thereof to be used for this purpose include those exemplified as the polyester (meth) acrylate compounds of the above-mentioned polyfunctional (meth) acrylate compounds. Examples of the compound having at least one (meth) acryloyloxy group and hydroxyl group include those exemplified for the urethane (meth) acrylate oligomer.

Examples of other urethane (meth) acrylate oligomers include, in addition to the polymerizable oligomer as described above, a compound obtained by reacting an isocyanate with a hydroxyl group of a hydroxyl group-containing polyester, a hydroxyl group-containing polyether or a hydroxyl group-containing (meth) . The hydroxyl group-containing polyester preferably used for this purpose is obtained by an esterification reaction of a polyhydric alcohol with a compound having a carboxylic acid or a plurality of carboxyl groups and / or an anhydride thereof. Examples of the compound having a polyhydric alcohol and a plurality of carboxyl groups and / or anhydrides thereof include those exemplified as polyester (meth) acrylate compounds of a polyfunctional (meth) acrylate compound. The hydroxyl group-containing polyether which is preferably used is obtained by adding one or more kinds of alkylene oxide and / or? -Caprolactone to the polyhydric alcohol. The polyhydric alcohol may be the same as that usable for the hydroxyl group-containing polyester. Examples of the hydroxyl group-containing (meth) acrylate ester that is preferably used include those exemplified as urethane (meth) acrylate oligomers of polymerizable oligomers. The isocyanate may be any compound having at least one isocyanate group in the molecule, but is particularly preferably a divalent isocyanate compound such as tolylene diisocyanate, hexamethylene diisocyanate, or isophorone diisocyanate.

These polymerizable oligomers may be used alone or in combination of two or more.

(2) Photopolymerization initiator

The photopolymerization initiator can be appropriately selected depending on the kind of the active energy ray to be applied to the production of the antiglare film. When an electron beam is used as an active energy ray, a coating liquid containing no photopolymerization initiator may be used for the production of an antiglare film. As the photopolymerization initiator, for example, an acetophenone photopolymerization initiator, a benzoin photopolymerization initiator, a benzophenone photopolymerization initiator, a thioxanthone photopolymerization initiator, a triazine photopolymerization initiator, and an oxadiazole photopolymerization initiator. Examples of the photopolymerization initiator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,2'-bis (o-chlorophenyl) -4,4 ', 5,5'-tetraphenyl- -Imidazole, 10-butyl-2-chloroacridone, 2-ethyl anthraquinone, benzyl, 9,10-phenanthrenequinone, camphaquinone, methyl phenylglyoxylate, and titanocene compounds. The photopolymerization initiator is used in an amount of usually 0.5 to 20 parts by weight, preferably 1 to 5 parts by weight, per 100 parts by weight of the active energy ray curable resin.

(3) Other optional components constituting the coating liquid

The coating liquid may contain an organic solvent in order to improve the coating property to the transparent support. Examples of the organic solvent include aliphatic hydrocarbons such as hexane, cyclohexane and octane; Aromatic hydrocarbons such as toluene and xylene; Alcohols such as ethanol, 1-propanol, isopropanol, 1-butanol and cyclohexanol; Ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; Esters such as ethyl acetate, butyl acetate and isobutyl acetate; Glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether and propylene glycol monoethyl ether; Esterified glycol ethers such as ethylene glycol monomethyl ether acetate and propylene glycol monomethyl ether acetate; Cellosolves such as 2-methoxyethanol, 2-ethoxyethanol and 2-butoxyethanol; And carbitols such as 2- (2-methoxyethoxy) ethanol, 2- (2-ethoxyethoxy) ethanol and 2- (2-butoxyethoxy) ethanol . These solvents may be used alone or in combination of two or more thereof if necessary. When the coating liquid contains a solvent, it is necessary to evaporate the solvent after coating. Therefore, the solvent preferably has a boiling point in the range of 60 캜 to 160 캜. The saturated vapor pressure at 20 占 폚 is preferably in the range of 0.1 kPa to 20 kPa.

(Other processes optionally arranged in the coating process and arrangement of the coating process)

When the coating liquid contains a solvent, it is preferable to provide a drying step after the coating step, before the main curing step and before the pre-curing step, in which the solvent is evaporated and dried. The drying can be carried out by passing the transparent support 81 after the coating layer is formed, for example, through the inside of the drying zone 84 as in the example shown in Fig. The drying temperature is appropriately selected depending on the type of solvent or transparent support to be used. But is not limited thereto. When there are a plurality of drying furnaces, the temperature may be changed for each drying furnace. The thickness of the coating layer after drying is preferably 1 to 30 mu m.

The coating process as described above and, if necessary, the drying process are further carried out to form a laminate in which a coating layer is laminated on the transparent support.

[P2] Pre-hardening process

The preliminary curing step is a step of preliminarily curing both end regions by irradiating active energy rays to both end portions of the coating layer in the width direction of the coating layer prior to the final curing step to be described later. 8 is a cross-sectional view schematically showing a preliminary curing step. In Fig. 8, the end regions 82b existing at both ends in the width direction of the coating layer (direction orthogonal to the transport direction) are regions having a predetermined width from the end portion including the end portion of the coating layer.

In the preliminary curing step, the both end regions are previously cured so that the adhesion with the transparent support 81 at that portion is further increased. In the subsequent main curing step and subsequent steps, a part of the cured resin is peeled off and falls , It is possible to prevent the process from being contaminated. The end region 82b may be an area of 5 mm to 50 mm from the end of the coating layer 82, for example.

7 and 8, the irradiation of the active energy ray to the end region of the coating layer is carried out by irradiating the coating layer 82 (for example, the coating zone 82 Can be performed by irradiating an active energy ray using an active energy ray irradiating device 85 such as an ultraviolet irradiator provided in the vicinity of both ends of the coating layer 82 side with respect to the transparent support 81 . The active energy ray irradiating device 85 may be provided on the transparent support 81 side as long as it can irradiate the active energy ray to the end region 82b of the coating layer 82. [

The kind of the active energy ray and the light source are the same as the main curing step described later. When the active energy ray is ultraviolet ray, the accumulated light quantity at ultraviolet ray UVA (wavelength 400 to 315 nm) is preferably 10 mJ / cm2 to 400 mJ / cm2, more preferably 50 mJ / cm2 to 400 mJ / cm2 desirable. When irradiated so that the accumulated light quantity becomes 50 mJ / cm 2 or more, deformation in the subsequent main curing step can be more effectively prevented. On the other hand, when the accumulated light quantity exceeds 400 mJ / cm 2, the curing reaction proceeds excessively, and as a result, the resin peeling may occur at the boundary between the cured portion and the uncured portion due to a difference in film thickness or distortion of internal stress.

[P3] Main Curing Process

In the final curing step, the active energy ray is irradiated on the surface of the coating layer with the mold surface (molding surface) having the desired surface concavo-convex shape closely attached, and the coating layer is cured to cure the coating layer, Thereby forming a cured resin layer. As a result, the coating layer is cured and the concave-convex shape of the mold surface is transferred to the surface of the coating layer. The mold used here is produced by continuously using the antiglare film as a long product, in the form of a roll, and by using the roll-shaped mold base in the previously described mold manufacturing method.

As shown in Fig. 7, for example, in the coating zone 83 (in the case of carrying out the drying step, the drying zone 84, and in the case of performing the preliminary curing step described above, An active energy ray irradiating device 86 such as an ultraviolet irradiating device disposed on the side of the transparent support 81 with respect to the laminate having the coated layer after passing through the preliminary curing zone irradiated by the device 85 And irradiating an active energy ray.

First, the roll-shaped mold 87 is closely contacted to the surface of the coated layer of the layered product having the coated layer formed thereon by the use of a nip roll 88 or the like and placed on the transparent support 81 side in this state The activated energy ray irradiating device 86 irradiates an active energy ray to cure the coating layer. Here, "curing the coating layer" means that the active energy ray-curable resin contained in the coating layer receives the energy of the active energy ray and causes the curing reaction. Use of the nip roll 88 is effective in preventing bubbles from being mixed in between the coating layer of the laminate and the mold. The active energy ray irradiating device 86 may use one or more groups.

After the active energy ray irradiation, the laminate is peeled from the mold 87 with the nip roll 89 at the exit side as a fulcrum. The laminate comprising the obtained transparent support and the cured coating layer becomes an antiglare film having the cured coating layer as an antiglare layer. The obtained antiglare film is usually wound by a film winding device 90. At this time, for the purpose of protecting the antiglare layer, a protective film made of polyethylene terephthalate, polyethylene or the like may be adhered to the surface of the antiglare layer through a pressure-sensitive adhesive layer having re-releasability. Here, the case where the metal mold to be used is in a roll shape has been explained, but a metal mold other than the roll shape may also be used. Further, after peeling from the mold, an additional active energy ray may be irradiated.

The active energy ray used in this step can be appropriately selected from ultraviolet rays, electron rays, near ultraviolet rays, visible rays, near-infrared rays, infrared rays, and x rays depending on the kind of the active energy ray curable resin contained in the coating liquid. Ultraviolet ray is particularly preferable because it is preferable and easy to handle and high energy can be obtained. Therefore, as described above, the UV emboss method is preferable as the optical embossing method.

Examples of the ultraviolet light source include low pressure mercury lamps, medium pressure mercury lamps, high pressure mercury lamps, ultra high pressure mercury lamps, carbon arc lamps, electrodeless lamps, metal halide lamps, and xenon arc lamps. An ArF excimer laser, a KrF excimer laser, an excimer lamp, or a synchrotron radiation can also be used. Of these, ultrahigh pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, electrodeless lamps, xenon arc lamps, and metal halide lamps are preferably used.

Examples of the electron beam include an electron beam of 50 to 1000 keV emitted from various electron beam accelerators such as a Cockcroft-Walton type, a Bandegraph type, a resonance type, an insulation core type, a linear type, a dinamitron type, , And preferably an electron beam having an energy of 100 to 300 keV.

When the active energy ray is ultraviolet ray, the accumulated light quantity in UVA (wavelength 400 to 315 nm) of ultraviolet ray is preferably 100 mJ / cm2 to 3000 mJ / cm2, more preferably 200 mJ / mJ / cm &lt; 2 &gt; Further, in some cases, the transparent support absorbs ultraviolet rays on the short wavelength side, so that the total amount of ultraviolet UVV (wavelength 395 to 445 nm) in the wavelength region including visible light is preferably set to be a desirable value The dose may be adjusted. In this case, the accumulated amount of light in the UVV is preferably 100 mJ / cm2 or more and 3000 mJ / cm2 or less, more preferably 200 mJ / cm2 or more and 2000 mJ / cm2 or less. If the accumulated light quantity is less than 100 mJ / cm 2, the curing of the coating layer becomes insufficient, the hardness of the obtained antiglare layer becomes low, or the uncured resin tends to adhere to the guide roll or the like to cause process contamination. If the accumulated light quantity exceeds 3000 mJ / cm 2, the transparent support may shrink due to heat radiated from the ultraviolet irradiator to cause wrinkles.

[Uses of antiglare film]

The antiglare film of the present invention obtained as described above is used for an image display apparatus or the like and is usually used as a visible side protective film of a viewer side polarizing plate bonded to a polarizing film. That is, the polarizing plate to which the anti-ghost film is bonded is disposed on the surface of the image display apparatus. Further, as described above, when a polarizing film is used as the transparent support, an antiglare film integrated with a polarizing film can be obtained. Therefore, such an antiglare film integrated with a polarizing film can be applied to an image display apparatus. The image display device equipped with the antiglare film of the present invention has sufficient diaphragmability at a wide viewing angle and can also prevent the occurrence of whitening and flashing at the same time.

[ Example ]

Hereinafter, the present invention will be described in more detail by way of examples. In the examples,% and parts representing the content or amount are based on the weight unless otherwise specified. The evaluation method of the mold or the antiglare film in the following examples is as follows. On the other hand, the antiglare film of the present invention was evaluated by the same method as the following evaluation method.

[1] Measurement of surface shape of antiglare film

(Inclination angle of the surface relief shape)

The elevation of the surface of the antiglare film was measured using a three-dimensional microscope "PL 占 2300" (manufactured by Sensofar). In order to prevent warpage of the measurement sample, an optically transparent pressure-sensitive adhesive was used and the surface opposite to the antiglare layer of the measurement sample was bonded to the glass substrate and used for measurement. The magnification of the objective lens at the time of measurement was set at 50 times. The horizontal resolutions? X and? Y were all 0.332 占 퐉 and the measurement area was 255 占 퐉 占 191 占 퐉. Based on the obtained measurement data, the average value of the inclination angles of the surface irregularities was obtained based on the above-described algorithm, and the standard deviation was obtained therefrom.

[Average value and variation coefficient of area of Voronoi polygon]

The surface morphology of the antiglare film was measured using a three-dimensional microscope "PL 占 2300" (manufactured by Sensofar). In order to prevent the sample from warping, an optically transparent pressure-sensitive adhesive was used to bond the glass substrate so that the uneven surface became the surface, and then used for measurement. When measuring, the magnification of the objective lens was set to 50 times. The horizontal resolutions? X and? Y were all 0.332 占 퐉 and the measurement area was 255 占 퐉 占 191 占 퐉. From the measurement data thus obtained, Voronoi dividing the convex portion of the fine concavo-convex surface on the surface of the fine concavo-convex portion was performed to obtain the average value and standard deviation of the area of the Voronoi polygon, and the coefficient of variation = (standard deviation / × 100 (%) was obtained.

[2] Measurement of Optical Properties of Antiglare Film

[Hayes]

The total haze of the antiglare film was measured by using an optically transparent pressure sensitive adhesive to adhere the surface opposite to the antiglare layer of the measurement sample to the glass substrate and to cause the light from the glass substrate side to enter the antiglare film bonded to the glass substrate , And the measurement was conducted using a haze meter "HM-150" type manufactured by Murakami Shikishi Sai Gijutsu Kenshoku Co., Ltd. in accordance with the aforementioned JIS K7136: 2000. The surface haze was determined by finding the internal haze of the antiglare film,

Surface Haze = Overall Haze - Inner Haze

Lt; RTI ID = 0.0 &gt; haze. &Lt; / RTI &gt; The inner haze was measured in the same manner as the total haze after adhering a triacetyl cellulose film having a haze of 0 with glycerin to the viscous layer surface of the measurement sample after measuring the total haze.

[Transparent Sharpness]

In accordance with the above-mentioned JIS K7374: 2007, the transparency clearness of the antiglare film was measured using a specularity meter "ICM-1DP" manufactured by Suga Shikeki Co., Ltd. Also in this case, an optically transparent pressure-sensitive adhesive was used to adhere the surface opposite to the antiglare layer of the measurement sample to the glass substrate in order to prevent the sample from being warped. In this state, light was incident on the glass substrate side and the measurement was made. Here, the measured values are the sum of values measured using five types of optical combs having widths of the shielding portion and the transmitting portion of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm, respectively.

[Reflection sharpness measured at a light incidence angle of 45 [deg.])

In accordance with JIS K7374: 2007 mentioned above, the reflection sharpness of the antiglare film was measured using a mood meter "ICM-1DP" manufactured by Suga Shikenki Co., Ltd. In this case as well, the surface opposite to the antiglare layer of the measurement sample is bonded to the black acrylic resin substrate using an optically transparent pressure-sensitive adhesive in order to prevent the sample from warping and also to prevent reflection from the back surface. . In this state, light was incident at 45 deg. From the side of the antiglare layer side, and measurement was performed. Here, the measured values are the sum of values measured by using four types of optical combs having widths of the light shielding portion and the transmitting portion of 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm, respectively.

[Reflection sharpness measured at an incident angle of light of 60 degrees]

Except that the angle of incidence of light was changed to 60 DEG, the same method as that of the reflection sharpness measured at an incident angle of 45 DEG of the above light was used.

[3] Evaluation of anti-glare performance of antiglare film

[Evaluation to check visually, whiteness]

In order to prevent reflection from the back surface of the antiglare film, a surface opposite to the antiglare layer of the measurement sample is bonded to the black acrylic resin substrate using a pressure-sensitive adhesive, and in this state, And the degree of non-reflectance and degree of whitening of the fluorescent lamp were evaluated. With regard to non-immersion, evaluation was made when the antiglare film was observed from the front and when it was obliquely observed at 30 °. The non-irritation and the whitening were evaluated according to the following criteria in three steps of 1 to 3, respectively.

Nonvisual 1: No impression is observed.

2: Some non-visible light is observed.

3: Visible light is clearly observed.

all sorts of flowers 1: No whitening is observed.

2: White pigment is slightly observed.

3: Whiteness is clearly observed.

[Evaluation of flashing]

The flashing was evaluated in the following order. That is, first, a photomask having a pattern of a unit cell shown in a plan view in FIG. 9 was prepared. In this figure, the unit cell 100 has a key-shaped chromium shielding pattern 101 with a line width of 10 mu m formed on a transparent substrate and a portion where the chromium shielding pattern 101 is not formed is formed in the opening 102 ). Here, the dimensions of the unit cells were 211 占 퐉 占 70 占 퐉 (lengthwise and widthwise of the drawing), and thus the dimensions of the openings were 201 占 퐉 占 60 占 퐉 (length × width of the drawing). A plurality of unit cells shown in the drawing are arranged in a longitudinal and lateral direction to form a photomask.

10, the chromium shielding pattern 111 formed on the glass substrate 112 of the photomask 113 is raised, and the chromium shielding pattern 111 on the light diffusion plate 120 of the light box 115 And a sample on which the antiglare film 110 is adhered to the glass plate 117 with an adhesive as a surface is placed on the photomask 113. [ A light source 116 is disposed in the light box 115. In this state, the degree of glare was visually observed at a position (119), which is about 30 cm away from the sample, in seven stages. Level 1 corresponds to a state in which flashing is not recognized at all, Level 7 corresponds to a state in which a glaring flash is observed, and Level 4 indicates a state in which a very slight flashing is observed.

[Evaluation of contrast]

The polarizing plates on both sides of the front and back sides were peeled from a commercially available liquid crystal television ("KDL-32EX550" manufactured by Sony Corporation). In place of these original polarizing plates, a polarizing plate "Sumikaran SRDB831E" manufactured by Sumitomo Chemical Co., Ltd. was bonded to the rear side and the display surface side through an adhesive so that the absorption axes thereof coincided with the absorption axes of the original polarizing plates, On the polarizing plate, an antiglare film described in each of the following examples was bonded through a pressure-sensitive adhesive so that the uneven surface became the surface. The thus obtained liquid crystal television was activated in the dark room, and the brightness was measured in a black display state and a white display state using a luminance meter "BM5A" type manufactured by TOPCON CORPORATION, and the contrast was calculated. Here, the contrast is expressed by the ratio of the luminance in the white display state to the luminance in the black display state. On the other hand, in the above-mentioned configuration, the contrast was similarly calculated in the configuration except for the antiglare film (the state in which the antiglare film was not bonded to the display side polarizing plate), and the result was that the antiglare film with respect to the contrast measured in the non- (%) Of the contrast measured in one state.

[4] Evaluation of patterns for producing antiglare film

The generated pattern data is regarded as two-gradation binary image data, and the gradation is expressed as a two-dimensional discrete function g (x, y). The horizontal resolutions? X and? Y of the discrete function g (x, y) were both 2 占 퐉. Dimensional function g (x, y) obtained is subjected to discrete Fourier transform to obtain a two-dimensional function G (f _x , f _y ). Dimensional function Γ (f _x , f _y ) of the two-dimensional power spectrum by squaring the absolute value of the two-dimensional function G (f _x , f _y ) and calculating a one-dimensional function Γ (f ), And the average frequency &lt; f &gt; and the standard deviation [sigma] _f were calculated.

&Lt; Example 1 >

[Production of mold for manufacturing anti-glare film]

An aluminum roll having a diameter of 300 mm (A6063 by JIS) was coated with copper ballard. The copper ballard plating was made of a copper plating layer / a thin silver plating layer / a surface copper plating layer, and the thickness of the entire plating layer was about 200 占 퐉. The copper-plated surface was mirror-polished, and the surface of the polished copper-plated surface was coated with a photosensitive resin and dried to form a photosensitive resin film. Subsequently, a pattern in which the pattern shown in Fig. 11 was repeatedly repeated was exposed on the photosensitive resin film by a laser beam and developed. Exposure by laser light and development were carried out using Laser Stream FX (manufactured by Sincla Laboratories). As the photosensitive resin, a positive type photosensitive resin was used. The pattern shown in Fig. 11 is prepared by passing through a plurality of Gaussian function type band-pass filters from a pattern having a random brightness distribution. The aperture ratio is 45%, and the average frequency &lt; f & And standard deviation σ _f are 0.091 ㎛ ^-1 and 0.102 ㎛ ^-1, respectively. In the drawing, laser exposure was performed so that the black portion became the exposed portion and the white portion became the unexposed portion. The relationship between the exposed portion and the unexposed portion is the same in Figs. 12 to 14 to be described later.

Thereafter, the first etching treatment was performed with a cupric chloride aqueous solution. The etching amount at that time was set to be 5 占 퐉. The photosensitive resin film was removed from the roll after the first etching treatment, and the second etching treatment was performed again with the cupric chloride aqueous solution. The etching amount at that time was set to be 10 占 퐉. Subsequently, the plating thickness was set to be 6 占 퐉, and nickel plating processing was performed. A DLC film was formed as a protective film on a nickel-plated roll by a sputtering method to prepare a mold. The thickness of the DLC film at this time was 0.5 mu m.

(Fabrication of antiglare film)

An ultraviolet ray curable resin composition was prepared in which the following components were dissolved in ethyl acetate at a solid content concentration of 60% and a film showing a refractive index of 1.53 after curing was formed.

Pentaerythritol triacrylate 60 parts

Multifunctional urethane acrylate 40 copies

(The reaction product of hexamethylene diisocyanate and pentaerythritol triacrylate)

2,4,6-trimethylbenzoyldiphenylphosphine oxide Part 5

This ultraviolet ray curable resin composition was coated on a triacetylcellulose (TAC) film having a thickness of 60 占 퐉 so that the thickness of the coating layer after drying was 5 占 퐉 and dried in a dryer set at 60 占 폚 for 3 minutes. The dried film was pressed against the molding surface (surface having concavo-convex shape) of the above-described mold by a rubber roll so that the coated layer after drying became the mold side and brought into close contact with each other. In this state, light from a high-pressure mercury lamp of intensity 20 mW / cm 2 was irradiated from the TAC film side so as to have an integrated light quantity of h-line conversion of 200 mJ / cm 2 to cure the coating layer to form an antiglare layer. Thus, the film having the antiglare layer formed on the TAC film was peeled from the mold to obtain a transparent antiglare film. This is referred to as antiglare film A.

&Lt; Example 2 >

A mold was produced in the same manner as in the production of the mold in Example 1 except that the etching amount in the second etching step was set to be 9 占 퐉. An antiglare film was produced in the same manner as in the production of the antiglare film in Example 1 except that this mold was used. The obtained antiglare film was used as the antiglare film B.

&Lt; Example 3 >

A mold was produced in the same manner as in the production of the mold in Example 1 except that the etching amount in the second etching step was set to be 11 mu m. An antiglare film was produced in the same manner as in the production of the antiglare film in Example 1 except that this mold was used. The obtained antiglare film is referred to as an antiglare film C.

<Example 4>

A mold was produced in the same manner as in the production of a mold in Example 1 except that a pattern in which the patterns shown in FIG. 12 were repeatedly arranged was exposed on the photosensitive resin film by laser light. An antiglare film was produced in the same manner as in the production of the antiglare film in Example 1 except that this mold was used. The obtained antiglare film is referred to as antiglare film D. The pattern shown in Fig. 12 is prepared by passing through a plurality of Gaussian function type band-pass filters from a pattern having a random brightness distribution. The aperture ratio is 45%, and the average frequency &lt; f & And standard deviations σ _f are 0.088 ㎛ ^-1 and 0.101 ㎛ ^-1, respectively.

&Lt; Example 5 >

A mold was produced in the same manner as in the production of a mold in Example 1, except that a pattern in which the patterns shown in FIG. 13 were repeatedly arranged was exposed on the photosensitive resin film by laser light. An antiglare film was produced in the same manner as in the production of the antiglare film in Example 1 except that this mold was used. The obtained antiglare film is referred to as an antiglare film E. The pattern shown in Fig. 13 is obtained by passing through a plurality of Gaussian function type band-pass filters from a pattern having a random brightness distribution. The aperture ratio is 45%, and the average frequency <f> calculated from the one- And the standard deviation σ _f are 0.092 ㎛ ^-1 and 0.107 ㎛ ^-1, respectively.

&Lt; Comparative Example 1 &

A mold F was produced in the same manner as in the production of a mold in Example 1, except that the etching amount in the second etching step was set to be 8 占 퐉. An antiglare film was produced in the same manner as in the production of the antiglare film in Example 1 except that this mold was used. The obtained antiglare film is referred to as antiglare film F.

&Lt; Comparative Example 2 &

A surface of an aluminum roll (A6063 by JIS) having a diameter of 200 mm was coated with copper ballard so that the entire thickness of the plating layer was about 200 占 퐉. The same procedure as in the production of a mold in Example 1 except that a pattern in which the pattern shown in Fig. 14 was repeatedly repeated was exposed on the photosensitive resin film by using the aluminum roll having the copper ballard plating, To produce a mold. An antiglare film was produced in the same manner as in the production of the antiglare film in Example 1 except that this mold was used. The obtained antiglare film is used as the antiglare film G. The pattern shown in Fig. 14 is prepared by passing through a plurality of Gaussian function type band-pass filters from a pattern having a random brightness distribution. The aperture ratio is 45% and the average frequency &lt; f & And standard deviation σ _f are 0.087 ㎛ ^-1 and 0.094 ㎛ ^-1, respectively.

&Lt; Comparative Example 3 &

The surface of an aluminum roll having a diameter of 300 mm (A5056 by JIS) was mirror-polished and the polished aluminum surface was polished with zirconia beads "TZ-SX-17 ", manufactured by Fuji Seisakusho Co., Was blasted with a blast pressure of 0.1 MPa (gauge pressure, the same applies hereinafter) and a bead usage amount of 8 g / cm 2 (the usage per 1 cm 2 of the surface area of the roll, hereinafter the same) The surface of the aluminum roll was given unevenness. An aluminum roll having the unevenness obtained was subjected to electroless nickel plating to prepare a metal mold. At this time, the electroless nickel plating thickness was set to be 15 占 퐉. An antiglare film was produced in the same manner as in the production of the antiglare film in Example 1 except that this mold was used. The obtained antiglare film is referred to as antiglare film H.

&Lt; Comparative Example 4 &

A copper ballard plating was carried out on the surface of an aluminum roll having a diameter of 200 mm (A5056 according to JIS) so that the entire thickness of the plating layer was about 200 占 퐉. The copper-plated surface was mirror-polished and the same zirconia bead "TZ-SX-17" as used in Comparative Example 3 was applied to the polished surface with a blasting machine (manufactured by Fuji Seisakusho Co., Ltd.) 0.05 MPa and a bead usage amount of 6 g / cm &lt; 2 &gt; The obtained copper ballard-plated aluminum roll having unevenness was chrome-plated to produce a metal mold. At this time, the chromium plating thickness was set to be 6 占 퐉. An antiglare film was produced in the same manner as in the production of the antiglare film in Example 1 except that this mold was used. The obtained antiglare film was used as the antiglare film I.

[Evaluation results]

Table 1 shows the evaluation results of the antiglare film obtained in the above Examples and Comparative Examples.

The anti-glare films A to E (Examples 1 to 5) satisfying the requirements of the present invention had excellent anti-glare properties even when the viewing angle was oblique both at the front and the back, and had an effect of suppressing whitening and glare, . On the other hand, in the antiglare film F (Comparative Example 1), whitening occurred. The antiglare film G (Comparative Example 2) had insufficient flicker when observed in an oblique direction. In the antiglare film H (Comparative Example 3), flashing easily occurred. In the antiglare film I (Comparative Example 4), the retardation when observed in an oblique direction was insufficient, and whitening occurred.

1: antiglare film (or average surface thereof), 2: surface irregularities, 3: projection plane of the film,
5: principal normal of the film, 6: local normal with irregularities,
6a, 6b, 6c, 6d: Normal vector of the polygonal surface,
21: arbitrary point of the antiglare film surface, 22: antiglare film surface,
23: antiglare film reference plane, 24: projection plane of a circle centered at arbitrary point (21)
26: Voronoi division point, 27: Voronoi polygon,
28: Voronoi polygons which do not count on the average,
40: mold base material,
41: a plated surface polished through a first plating process and a polishing process,
45: maskless region to be etched by the first etching treatment,
46: a first surface relief shape formed by the first etching treatment,
47: second surface irregular surface shape reduced by the second etching treatment,
50: photosensitive resin film, 51: exposed area, 52: unexposed area,
60: mask,
70: final mold concave and convex surface shape-reduced by nickel plating,
71: nickel plated layer,
80: feed roll, 81: transparent support,
82: coating layer, 82b: end region of coating layer, 83: coating zone,
84: drying zone, 85: active energy ray irradiation apparatus for preliminary curing,
86: active energy ray irradiating device, 87: roll-shaped mold,
88, 89: nip roll, 90: film winding device,
100: unit cell, 101: shielding pattern, 102: opening,
110: antiglare film, 111: shielding pattern, 112: glass substrate,
113: photomask, 115: light box, 116: light source,
117: glass plate, 119: observation position of flashing, 120: light diffusion plate.
[Industrial applicability]
The antiglare film of the present invention is useful for an image display apparatus such as a liquid crystal display.

Claims (2)

An antiglare film comprising a transparent support and an antiglare layer having a fine surface relief shape formed thereon,
The total haze is 0.1% or more and 3% or less,
A surface haze of 0.1% or more and 2% or less,
The average value of the inclination angles of the surface irregularities is 0.2 to 1.2 degrees and the standard deviation of the inclination angles is 0.1 to 0.8 degrees,
An average value of the areas of the polygons formed when the Voronoi is divided on the surface of the convex portions of the convex portions of the surface irregularities is not less than 50 μm ^{2 and not} more than 150 μm ² and the coefficient of variation of the area of the polygon is not less than 40% 80% or less. 2. The method according to claim 1, wherein the sum Tc of transmission sharpness measured using five types of optical combs having widths of the light-shielding portion and the transmission portion of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm, respectively 375% or more,
The sum Rc (45) of the reflection sharpness measured at an incident angle of light of 45 ° is 180% or less using four kinds of optical combs having the widths of the shielding portion and the transmitting portion of 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm,
An antiglare film having a sum Rc (60) of 240% or less of reflection sharpness measured at an incident angle of light of 60 ° using four kinds of optical combs having a light shielding portion and a transmitting portion width of 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm, respectively .

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