KR20160091957A - Antiglare film - Google Patents

Abstract

Provided is an antiglare film which has excellent antifogging property even at a low viewing angle even at a low haze and can sufficiently suppress the occurrence of flare and glare when placed in an image display device.
1. 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% or less, or less than 0.2 ° 1.2 °, and the standard deviation of the inclination angle less than 0.1 ° 0.8 °, the power spectrum of the altitude of the surface irregularities, the spatial frequency 0.01 ㎛ ^-1, the spatial frequency and the spatial frequency 0.02 ㎛ ^-1 And the intensity I (0.01), I (0.02) and I (0.1) at 0.1 m ^-1 are respectively within a predetermined range.

Description

Antistatic Film {ANTIGLARE FILM}

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

An image display apparatus such as a liquid crystal display, a plasma display panel, a cathode ray tube (CRT) display, and an organic electroluminescence (EL) display has a configuration in which, in order to avoid deterioration of visibility due to external light, And an antiglare film is disposed on the surface.

As the antiglare film, a transparent film having a surface irregularity shape is mainly studied. Such an antiglare film exhibits anti-scattering property by reducing non-reflectance by scattering reflection of external light (external light scattering light) by surface irregularities. However, when the external light scattering light is strong, the entire display surface of the image display apparatus may become blurred or the display may become a whitish color. There is also a case where so-called " flashing " occurs in which the surface irregularities of the antiglare film interfere with the pixels of the image display device, and the luminance distribution is generated and becomes invisible. In view of the above, it is desired that the antiglare film sufficiently prevent the occurrence of this "desire" and "flash" while ensuring excellent antifogging property.

As such an anti-glare film, for example, Patent Document 1 discloses an anti-glare film in which glare does not occur even when placed in a high-definition image display device and fading is sufficiently prevented, Wherein an average length PSm of an arbitrary section curve of the surface irregularity shape is 12 占 퐉 or less, a ratio Pa / PSm of an arithmetic average height Pa to an average length PSm in the section curve is 0.005 or more and 0.012 or less, Wherein a ratio of a face having an oblique angle of 2 DEG or less is 50% or less, and a ratio of a face having an oblique angle of 6 DEG or less is 90% or more.

The anti-glare film disclosed in Patent Document 1 effectively suppresses the above-mentioned glare by making the average length PSm in an arbitrary cross-sectional curve very small, thereby eliminating the surface irregularities having a period of about 50 탆 which makes it easier to generate glare . However, in the antiglare film disclosed in Patent Document 1, when the haze is to be made smaller (when trying to make the haze lower), when the display surface of the image display device on which the antiglare film is arranged is observed in the oblique direction, . Therefore, the antiglare film disclosed in Patent Document 1 still had room for improvement in terms of the retardation at a wide viewing angle.

Japanese Patent Laid-Open No. 2007-187952

An object of the present invention is to provide an antiglare film which has excellent antiglare property even at a low viewing angle even at low viewing angle and can sufficiently suppress the occurrence of fading and glare when placed in an image display device.

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above problems, and as a result, they have completed the present invention. That is,

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,

An antiglare film having 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 surface irregularity shape is an antiglare film characterized in that the power spectrum of the surface thereof satisfies all of the following conditions (1) to (3).

(1) the spatial frequency 0.01 ㎛ ^{- 1} to the intensity I (0.01) or less than 2 ㎛ ⁴ 10 ㎛ ⁴ in;

(2) spatial frequency 0.02 ㎛ ^{- 1} to the intensity I (0.02) or less than 0.1 ㎛ ^{4 4} 1.5 ㎛ in; And

3, the spatial frequency 0.1 ㎛ ^{- 1} being less than the intensity I (0.1) is more than 0.0001 ㎛ ⁴ 0.01 ㎛ ⁴ in.

In the antiglare film of the present invention,

The sum Tc of the transmission sharpness measured using five types of optical combs having widths of the arm portion and the bright 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 degrees using four kinds of optical combs having widths of the arm portion and the nominal portion of 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm is 180% or less,

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

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an antiglare film which has sufficient diffusibility at a wide observation angle even at low haze and is sufficiently suppressed from occurrence of flare 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 relief shape of the antiglare film.
3 is a view for simply explaining the elevation of the surface relief shape of the antiglare film.
4 is a schematic view showing a state in which the elevation of the surface relief shape of the antiglare film is discretely obtained.
5 is a schematic diagram showing a state in which a one-dimensional power spectrum is calculated from a two-dimensional power spectrum of an elevation of a surface unevenness obtained as a discrete function.
6 is a view showing the one-dimensional power spectrum I (f) of the elevation of the surface relief shape of the antiglare film with respect to the spatial frequency f.
Fig. 7 is a diagram schematically showing a preferable example of the manufacturing method (first half portion) of the mold.
Fig. 8 is a diagram schematically showing a preferable example of the method for manufacturing a mold (latter half).
9 is a diagram schematically showing a preferred example of the production apparatus used in the method for producing an antiglare film of the present invention.
10 is a diagram schematically showing an appropriate preliminary curing step in the method for producing an antiglare film of the present invention.
11 is a diagram schematically showing a unit cell for glare evaluation.
12 is a diagram schematically showing a flashing evaluation apparatus.
13 is a view showing a part of a pattern A used in Examples 1 to 3 and Comparative Example 1. Fig.
14 is a view showing a part of a pattern B used in Comparative Example 2. Fig.

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

The antiglare film of the present invention is characterized in that 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 and the spatial frequency of the power spectrum of the surface irregularities ^-1, 0.02 ㎛ ^-1, and 0.1 ㎛ ^- the intensity in the ^first characterized in that in the above-described ranges, respectively.

Firstly, with respect to the antiglare film of the present invention, a description will be given of a method of obtaining an average value and a standard deviation of inclination angles and a power spectrum of an elevation of surface irregularity shape.

[Average value and standard deviation of inclination angle]

A method of obtaining an average value and a standard deviation of the tilt angles will be described.

The inventor of the present invention has found that it is very effective in obtaining an image display device which has excellent anti-glare performance and effectively prevents fade, in order to make the surface irregularity shape of the antiglare film exhibit a specific inclined angle distribution. That is, 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 angle is less than 0.2 deg., The unevenness of the surface irregularity shape becomes a substantially flat surface, and there is a possibility that sufficient antiglare performance can not be exhibited. When the average value of the inclination angle of the surface irregularity shape exceeds 1.2 degrees, the inclination angle becomes steep and the light from the surroundings can be easily condensed. Therefore, the image display apparatus provided with such an antiglare film tends to cause fading Loses. In addition, 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 antiglare performance may not be exhibited. In the case where the standard deviation of the tilt angle exceeds 0.8 deg., Even if the average value is within the predetermined range, there is a region where the tilt angle is steep in the surface irregularity shape, and the image display apparatus provided with such an anti- It becomes easier to do.

The term "angle of inclination of the surface irregularity shape" in the present invention means an angle of inclination of the surface irregularity shape at an arbitrary point P on the surface of the antiglare film 1 shown in FIG. Means an angle ψ. The angle ψ formed by the local normal line 6 affects the influence of the unevenness at the point P. The inclination angle of the surface relief shape can be obtained from 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. 2, a notable point A on a hypothetical plane FGHI indicated by a dotted line is determined, and a point A is determined in the vicinity of a noteworthy point A on the x-axis passing through the noteworthy point A Points C and E are taken symmetrically with respect to the point A in the vicinity of the point A and the point A on the y-axis passing through the point A in a substantially symmetrical manner and correspond to these points B, C, D and E The points Q, R, S, and T on the film surface 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 the point C on the y-axis and a straight line parallel to the x-axis passing through the point E on the y-axis and a straight line parallel to the y- 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 drawn to the upper side with respect to the plane FGHI. However, depending on the position where the point of interest A is taken, the position of the actual film surface may be on the upper side of the plane FGHI There are also cases that come to the bottom.

The inclination angle of the obtained surface shape data (surface shape data of the surface irregularity shape) corresponds to the point P on the actual film surface corresponding to the remarked point A and the four points B, C, D and E taken in the vicinity thereof 6b, 6c, and 6d of the polygon 4 plane, that is, the four triangles PQR, PRS, PST, and PTQ expanded by five points of Q, R, S, and T on the actual film plane, Of the average normal vector 6 obtained by averaging the average normal vectors. 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.

In order to set the average value of the inclination angle of the surface irregular shape to 0.2 to 1.2 degrees and to set the standard deviation of the inclination angle to 0.1 to 0.8 degrees, a resin solution in which the fine particles are dispersed is applied on the transparent support, If the method is to form random irregularities on the transparent support by exposing to the surface of the coating film, the particle size and dispersion state of the fine particles and the film thickness of the coating film may be adjusted. Generally, under the condition that the particle size of the fine particles is constant, the average value of the inclination angle is lowered by increasing the film thickness of the coating film. 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.

In the preferred method for obtaining the antiglare film of the present invention described later, an antiglare film satisfying the requirements of the present invention can be obtained by adjusting the etching amount of the etching step and the plating thickness of the second plating step. The average value and the standard deviation of the tilt angle can be reduced by reducing the etching amount of the etching process or increasing the plating thickness of the second plating process.

[Power spectrum of elevation of surface irregularities]

Hereinafter, the power spectrum of the elevation of the surface relief shape of the antiglare film will be described. 2 is a cross-sectional view schematically showing the surface of an antiglare film of the present invention. 2, the antiglare film 1 of the present invention has a transparent support 101 and an antiglare layer 102 formed on the transparent support 101. The antiglare layer 102 is formed on the opposite side of the transparent support 101 And has a surface relief shape having fine irregularities (2).

Herein, the "height of the surface irregular surface shape" in the present invention means an arbitrary point P on the surface of the film (1) and a virtual plane (103) having the height at the average height of the surface irregular surface 0 占 퐉) in the main normal direction 5 of the film (normal direction in the virtual plane 103).

Actually, the antiglare film has, as schematically shown in Fig. 1, an antiglare layer in which fine irregularities are formed on a two-dimensional plane. 1, the elevation of the surface relief shape is represented by a two-dimensional function h (x, y) of the coordinates (x, y) when the rectangular coordinates in the film plane are represented by (x, y) .

The elevation of the surface irregularities can be obtained from three-dimensional information of the surface shape measured by a confocal microscope, an interference microscope, an atomic force microscope (AFM), or the like. The horizontal resolution required for the measuring instrument is at least 5 μm or less, preferably 2 μm or less, and the vertical resolution is at least 0.1 μm or less, preferably 0.01 μm or less. The non-contact three-dimensional surface shape / roughness measuring instrument suitable for this measurement includes a New View 5000 series (manufactured by Zygo Corporation) and a 3-dimensional microscope PLμ2300 (manufactured by Sensofar). The measurement area is preferably at least 200 탆 x 200 탆, more preferably at least 500 탆 x 500 탆, since the resolution of the power spectrum of the elevation is required to be 0.005 탆 ^-1 or less.

Next, a method of obtaining the power spectrum of elevation from the two-dimensional function h (x, y) will be described. First, a two-dimensional function H (f _x , f _y ) is obtained from a two-dimensional function h (x, y) by a two-dimensional Fourier transform defined by equation (1).

Where f _x and f _y are frequencies in the x and y directions, respectively, and have a dimension of the reciprocal of the length. In the equation (1),? Is the circumferential ratio and i is the imaginary unit. The two-dimensional power spectrum I (f _x , f _y ) can be obtained by the formula (2) by squaring the absolute values of the obtained two-dimensional functions H (f _x , f _y ).

This two-dimensional power spectrum I (f _x , f _y ) represents the spatial frequency distribution of the surface irregularities of the antiglare film. Since the antiglare film is isotropic, the two-dimensional function I (f _x , f _y ) representing the two-dimensional power spectrum of the surface irregularities is a one-dimensional function I (f _x , f _y ) dependent only on the distance f from the origin f). Next, a method of obtaining the one-dimensional function I (f) from the two-dimensional function I (f _x , f _y ) is shown. First, the two-dimensional function I (f _x , f _y ), which is the two-dimensional power spectrum of the elevation, is displayed in polar coordinates based on equation (3).

Where θ is the angle of declination in the Fourier space. The one-dimensional function I (f) can be obtained by calculating the rotation average of the two-dimensional function I (fcosθ, fsinθ) displayed in polar coordinates on the basis of equation (4). The one-dimensional function I (f) obtained from the rotation average of the two-dimensional function I (f _x , f _y ), which is the two-dimensional power spectrum of the elevation, is also referred to as a one-dimensional power spectrum I (f).

0.01 ㎛ spatial frequency of the one-dimensional power spectrum I (f), which is calculated from the elevation of the anti-glare film, the surface irregularities of the present ^invention and the intensity I (0.01) in the ^first, the intensity of the spatial frequency 0.02 ㎛ ^-1 I (0.02) and the intensity I (0.1) at a spatial frequency of 0.1 탆 ^-1 are within a specific range.

Hereinafter, a method of obtaining the two-dimensional power spectrum of the elevation of the surface relief shape of the antiglare film will be described in more detail. The three-dimensional information of the surface shape actually measured by the confocal microscope, the interference microscope, the atomic force microscope and the like is generally obtained as discrete values, i.e., elevations corresponding to a plurality of measurement points. Fig. 4 is a schematic diagram showing a state in which a function h (x, y) representing an elevation is discretely obtained. As shown in Fig. 4, a rectangular coordinate in the film plane is represented by (x, y), and a line segmented by Δx in the x-axis direction on the film projection plane 3 and a line segmented by Δy in the y- In the actual measurement, the elevation of the surface irregularity shape is obtained as a discrete table correction value for each area? X 占 y divided by each dashed line on the film projection surface 3.

If the measurement range in the x-axis direction is X = M? X and the measurement range in the y-axis direction is Y = N? Y as shown in Fig. 4, the number of the obtained elevation values is determined by the measurement range and? X and? Y, The number of the obtained elevation values is M × N.

(M? X, n? Y) (where m is not less than 0 but not more than M-1 and n is not less than 0 but not more than N-1) as shown in Fig. 4, The elevation of the point P on the film surface corresponding to the point A can be represented by h (m? X, n? Y).

Here, the measurement intervals [Delta] x and [Delta] y depend on the horizontal resolution of the measuring instrument, and in order to evaluate the surface irregularity shape with good precision, both [Delta] x and [Delta] y are preferably 5 [micro] m or less and more preferably 2 [micro] m or less. In addition, as described above, the measurement ranges X and Y are all preferably 200 m or more, and more preferably 500 m or more.

In this way, in actual measurement, the function indicating the elevation of the surface relief shape is obtained as a discrete function h (x, y) having M x N values. Therefore, the two-dimensional function H (f _x , f _y ) obtained by the two-dimensional Fourier transform of the two-dimensional function h (x, y) of the elevation of the surface irregularities can also be expressed as discrete Can be obtained as a discrete function by the Fourier transform as shown in equation (5).

Here, j in the equation (5) is an integer of -M / 2 or more and M / 2 or less, and k is an integer of -N / 2 or more and N / 2 or less. Further,? F _x and? F _y are frequency intervals in the x direction and y direction, respectively, and are defined by equations (6) and (7).

The two-dimensional power spectrum I (f _x , f _y ) can be obtained as shown in equation (8) by squaring the absolute value of the discrete function H (f _x , f _y ) obtained by equation (5).

In the equation (8), | H (j? F _x , k? F _y ) | ² is divided by MN DELTA x DELTA y in order to standardize the fact that the integral range differs depending on the measurement area in the case of actual measurement.

The two-dimensional power spectrum I (f _x , f _y ) obtained as a discrete function also shows the spatial frequency distribution of the surface relief shape of the antiglare film. Since the antiglare film is isotropic, the two-dimensional discrete function I (f _x , f _y ) representing the two-dimensional power spectrum of the surface irregular shape is also a one-dimensional discrete function (f _x , f _y ) depending only on the distance f from the origin Can be expressed as a function I (f). When the one-dimensional discrete function I (f) is obtained from the two-dimensional discrete function I (f _x , f _y ), the rotation average can be calculated as in the case of the equation (4). The discrete rotational averages of the two-dimensional discrete function I (f _x , f _y ) can be calculated by equation (9).

Here, when M > = N, 1 is an integer of 0 or more and N / 2 or less, and when M < N, l is an integer of 0 or more and M / 2 or less. Further,? F is the distance between the origin and? F = (? F _x +? F _y ) / 2. Further, Θ (x) is a Heaviside function defined by equation (10), and f _jk is the distance from the origin at (j, k) and is calculated by equation (11).

The calculation shown in Expression (9) will be described with reference to FIG. The function Θ (f _jk - (l-1/2) Δf) is 0 when f _jk is less than (l-1/2) Δf and is 1 when it is more than (l-1/2) _jk - (l + 1/2) Δf) is 0 when f _jk is less than (l + 1/2) Δf and is 1 when it is not less than (l + _{f jk - (l-1/} 2) Δf) -Θ (f jk - (l + 1/2) Δf) are, f _jk is (l-1/2) Δf or more (l-1/2) Δf below 1, and 0 otherwise. Where f _jk is in a frequency space, the origin _{○ (f x = 0, f} y = 0) , because the distance it is from, the denominator of equation (9) is the distance from the origin ○ f _jk is (l-1/2) The number of all the points (points in Fig. 5) located below? F or above (l + 1/2)? F is calculated. The numerator of equation (9) is a numerator of I (f _x , f _y ) of all points located at a distance f _jk from the origin O to (l-1/2) (A total value of I (f _x , f _y ) at the point [omega] in Fig. 5) is calculated.

Generally, the one-dimensional power spectrum obtained by the above method includes noise in measurement. In order to eliminate the influence of the noise in obtaining the one-dimensional power spectrum, the elevation of the surface irregularities at a plurality of locations on the antiglare film is measured, and the average value of the one-dimensional power spectrum obtained from the elevation of the surface irregularities is It is preferable to use it as the one-dimensional power spectrum I (f). The number of sites for measuring the elevation of the surface irregularities on the anti-ghost film is preferably 3 or more, and more preferably 5 or more.

Fig. 6 shows I (f) of the one-dimensional power spectrum of the elevation of the surface irregularity shape thus obtained. The one-dimensional power spectrum I (f) in FIG. 6 is obtained by averaging the one-dimensional power spectra obtained from the elevation of the surface concave-convex shapes at five different places on the antiglare film.

The anti-glare film of the invention, the surface spatial frequency 0.01 ㎛ of a one-dimensional power spectrum I (f), which is calculated from the altitude of the concave-convex shape ^- and the intensity I (0.01) in the ¹ 2 ㎛ ⁴ or more and 10 ㎛ ^4, space frequency 0.02 ㎛ ^- the intensity I (0.02) in the ^first and at least 0.1 ㎛ ⁴ 1.5 ㎛ ⁴ or less, the spatial frequency 0.1 ㎛ ^- the intensity I (0.1) in a ¹ characterized in that not more than 0.0001 ㎛ ⁴ more than 0.01 ㎛ ⁴ do. Since the one-dimensional power spectrum I (f) is obtained as a discrete function, the intensity I (f ₁ ) at a specific spatial frequency f ₁ can be interpolated as shown in equation (12).

The antiglare film of the present invention has the strength at the specific spatial frequency set in each of the predetermined ranges to cause occurrence of fainting and glare due to the synergistic effect of the haze described later and the average value of the inclination angles of the surface concave- , While exhibiting excellent anti-glare properties. In order to further exhibit such an effect, the intensity I (0.01) is preferably not less than 2.5 μm ^{4 and not} more than 9 μm ⁴ , more preferably not less than 3 μm ^{4 and not} more than 8 μm ⁴ . Likewise, the strength I (0.02) is preferably 0.2 to ⁴ μm and not more than 1.2 μm ^4, more preferably 0.25 to ⁴ μm and 1 μm ⁴ or less, and the strength I (0.1) is preferably not less than 0.0003 μm ^{4 and not} more than 0.0075 μm ⁴ , more preferably from 0.0005 ㎛ ⁴ or more than ⁴ 0.005 ㎛.

When I (0.01) is less than the above range, undulations of a period of about 100 占 퐉 (corresponding to 0.01 占 퐉 ^-1 at a spatial frequency), which contributes to the antiglare effect when the antiglare film is observed in an oblique direction, The repellency becomes insufficient. When I (0.01) exceeds the above range, undulations of the period of about 100 占 퐉 become too large, the micro concavity and convexity of the antiglare film becomes rough, and the haze tends to rise.

When the I (0.02) is less than the above range, the undulations of the period of about 50 占 퐉 (corresponding to 0.02 占 퐉 ^-1 at the spatial frequency) contributing to the antiglare effect when the antiglare film is observed at the front face are reduced, The present state becomes insufficient. When I (0.02) exceeds the above range, undulation of a period of about 50 占 퐉 becomes too large and glare occurs.

In the case where I (0.1) is less than the above range, the concavity and convexity of the short period of about 10 占 퐉 (corresponding to 0.1 占 퐉 ^-1 at the spatial frequency) is very small and the surface irregularity shape of the antiglare film is formed only in the concavo- And the surface texture of the antiglare film becomes rough, which is not preferable. When I (0.1) exceeds the above range, scattering due to the surface irregularities of a short period of about 10 占 퐉 becomes strong, and desire is liable to occur.

[Total haze, surface haze]

The antiglare film of the present invention has a total haze of not less than 0.1% and not more than 3% with respect to the normal incident light and exhibits a surface haze of not less than 0.1% and not more than 2% in order to exhibit antifogging properties and prevent fretting. The total haze of the antiglare film can be measured by a method in accordance with the method described in JIS K7136. An image display device in which an antiglare film having a total haze or surface haze of less than 0.1% is disposed is not preferable because it does not exhibit sufficient diffusibility. The antiglare film when the total haze exceeds 3% or the surface haze exceeds 2% is not preferable because the image display device in which the antiglare film is disposed causes fading. In addition, such an image display apparatus also has a problem that the contrast thereof becomes insufficient.

The lower the internal haze that can be obtained by subtracting the surface haze from the total haze, the more desirable it is, and specifically the haze is preferably 2.5% or less. 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)]

In the antiglare film of the present invention, it is preferable that the sum Tc of the transmission clarity determined under the following measurement conditions is 375% or more. The sum of transmission sharpness Tc is calculated by measuring the sharpness of each image by using an optical comb of a predetermined width by a method in accordance with JIS K 7105, and then calculating the sum. Specifically, the image clarity was measured using five kinds of optical combs each having a ratio of the width of the arm portion and the width of the name portion of 1: 1 and the widths of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm, To obtain Tc. When the anti-glare film having a Tc of less than 375% is arranged in an image display device with higher image clarity, the anti-glare film may easily become flicker. The upper limit of Tc is selected within a range of 500% or less of its maximum value. However, if the Tc is excessively high, an image display apparatus which easily deteriorates the retardation from the front surface can be obtained.

The antiglare film of the present invention preferably has a reflectance sharpness Rc (45) measured with incident light at an incident angle of 45 degrees of 180% or less. The reflection sharpness Rc (45) is measured by a method in accordance with JIS K 7105 in the same manner as Tc. Four types of optical combs having the widths of 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm And the total of the measured sharpnesses is obtained as Rc (45). When the Rc (45) is 180% or less, the image display device having such an antiglare film is preferable because the retardation when viewed from the front and oblique directions becomes better. 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 desire or glare.

The antiglare film of the present invention preferably has a reflectance sharpness Rc (60) of 240% 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 K 7105 which is the same as the reflection sharpness Rc (45) except that the incident angle is changed. When the Rc (60) is 240% or less, the image display device provided with the antiglare film is preferable because the retardation when observed in the oblique direction becomes better. The lower limit of the Rc (60) is not particularly limited, but is preferably 150% or more, for example, in order to further suppress occurrence of desire or glare.

[Method of producing antiglare film of the present invention]

The antiglare film of the present invention is produced, for example, as follows. The first method is a method in which a surface irregular shape based on a predetermined pattern is prepared by preparing a mold for forming fine irregularities formed on a molding surface and transferring the shape of the irregular surface of the mold to the transparent support, And the transparent support is peeled from the mold. A second method is a coating method comprising the steps of preparing a composition containing fine particles, a resin (binder) and a solvent and dispersing the fine particles in a resin solution, applying the composition onto a transparent support, A coating film containing fine particles) is cured. 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 coating film thickness and the coagulation state of the fine particles by the composition of the composition and the drying conditions of the coating film. From the viewpoints 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 form the antiglare layer having the surface irregularities having the above-described characteristics with good precision, the fine irregularities forming mold (hereinafter sometimes abbreviated as " mold ") is important. More specifically, the surface irregularities (hereinafter sometimes referred to as " mold irregularities ") of the metal mold are formed on the basis of a predetermined pattern, and the predetermined pattern has a spatial frequency of 0.01 ㎛ ^- strength at ¹ Γ (0.01) and the spatial frequency 0.02 ㎛ ^- and the ratio Γ (0.02) / Γ (0.01 ) of the intensity Γ (0.02) in the ^first 1.2 to 0.05, the spatial frequency 0.01 ㎛ ^{- 1} strength Γ (0.01) and the spatial frequency in the 0.1 ^㎛-ratio Γ (0.1) / Γ (0.01 ) of the intensity Γ (0.1) in the ^first is preferred if at least 25 4 or less. Here, the " pattern " means image data for forming a surface irregularity shape of the antiglare layer of the antiglare film, a mask having a light transmitting portion and a light shielding portion, and the like.

First, a method for 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 shown, for example, when the pattern is image data. First, after converting the image data into binarized image data of two gradations, the gradation is represented by a two-dimensional function g (x, y). Dimensional function G (f _x , f _y ) by Fourier transforming the obtained two-dimensional function g (x, y) as shown in the following equation (13) By squaring the absolute value of G (f _x , f _y ), a two-dimensional power spectrum Γ (f _x , f _y ) is obtained. Here, x and y represent the Cartesian coordinates in the image data plane. Further, f _x and f _y represent frequencies in the x and y directions, respectively, and have dimensions of reciprocal of length.

In the equation (13),? Is the circumferential rate and i is the imaginary unit.

This 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 for obtaining the one-dimensional function Γ (f) from the two-dimensional function Γ (f _x , f _y ) will be described. First, the two-dimensional function Γ (f _x , f _y ), which is the two-dimensional power spectrum of the gradation of the pattern, is expressed in polar coordinates as shown in equation (15).

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) in polar coordinates, as shown in Eq. (16). 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 good precision, the spatial frequency of the one-dimensional power spectrum of the pattern is 0.01 ㎛ ^- the ratio of the strength Γ (0.01) and the spatial frequency 0.02 ㎛ strength Γ (0.02) at the ^-1 in the ^first Γ (0.02) / Γ (0.01 ) is 0.05, and 1.2 or less, the spatial frequency 0.01 ^㎛-ratio Γ (0.1 strength Γ (0.1) in the ^{first-strength} in the ^first Γ (0.01) and the spatial frequency 0.1 ㎛ ) /? (0.01) is preferably 4 or more and 25 or less.

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 can be obtained in the same way from the two-dimensional power spectrum of the pattern.

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 maximum value of the two-dimensional function g ) Of the difference between the minimum value and the minimum value. 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. With respect to 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 resist means the ratio of the exposed area to the entire surface area of the coating film when image data is drawn on the coating film of the positive resist. On the other hand, the aperture ratio when the resist used in the lithography method is a negative resist means the ratio of the unexposed area to the entire surface area of the coating film when 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 can be produced by forming each of the intensity ratios Γ (0.02) / Γ (0.01) and Γ (0.1) / Γ , And can be produced according to the first method using the mold.

In order to generate a pattern of a one-dimensional power spectrum having such an intensity ratio, a pattern prepared by randomly arranging dots or a pattern having a random brightness distribution in which the density is determined by a random number or a similar random number generated by a calculator ), And removes a component in a specific spatial frequency range from the preliminary pattern. To remove the component of the specific spatial frequency range, the preliminary pattern may be passed through a bandpass 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 mold 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 emboss method in which an antiglare layer is formed on a transparent support.

Examples of the embossing method include an optical embossing method using a photo-curable resin, a hot embossing method using a thermoplastic resin, and the like. Above all, from the viewpoint of productivity, the optical emboss method is preferable.

The optical embossing method is a method in which a photo-curable resin layer is formed on a transparent support (a surface of a transparent support), and the photo-curable resin layer is cured on the surface of the metal mold concavity and convexity, It is a method of transferring to a photocurable resin layer. Specifically, the photo-curing resin layer formed by applying the photo-curable resin on the transparent support is placed in close contact with the surface of the mold unevenness, and light (the light which can be cured by the photo-curable resin is used from the transparent support side ) Is cured to cure the photo-curable resin (the photo-curing resin included in the photo-curable resin layer), and then the transparent support on which the photo-curable resin layer after curing is formed is peeled from the mold. In the antiglare film obtained by such a production method, the photocurable resin layer after curing becomes an antiglare layer. From the viewpoint of ease of manufacture, ultraviolet curable resin is preferable as the photo-curing resin. When the ultraviolet curable resin is used, ultraviolet light is used as the light to be irradiated (as the photo-curable resin, an emboss method Hereinafter referred to as " UV emboss method "). 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 the ultraviolet ray-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 the ultraviolet ray. Such a UV-curable resin is a concept including a monomer (multifunctional monomer), an oligomer and a polymer which are photopolymerized by ultraviolet irradiation, and a mixture thereof. Further, by using a photoinitiator suitably selected depending on the kind of the ultraviolet ray-curable resin, a resin capable of curing even visible light having a longer wavelength than ultraviolet ray can be used. Examples of the compatibility of the ultraviolet-curable resin and the like will be described later.

As the transparent support used in the UV embossing method, for example, glass or a plastic film can be used. Plastic films can be used if they have appropriate transparency and mechanical strength. Specifically, for example, a cellulose acetate-based resin such as TAC (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. When 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 device provided with the antiglare film is more likely to cause glare.

On the other hand, the hot emboss method is a method in which a transparent resin film formed of a thermoplastic resin is pressed and bonded to the surface of the mold concavity and convexity while being heated and softened, and the surface concavo-convex shape of the mold concave and convex surface is transferred to the transparent resin film. The transparent resin film used in the hot embossing method may be any substantially transparent as long as it is substantially optically transparent. Specifically, those exemplified as the transparent resin film used in the UV embossing method may be mentioned.

Next, a method of manufacturing a mold used in the embossing method will be described.

With regard to the method for producing a mold, it is preferable that the mold surface of the above-mentioned mold is formed so that a surface irregularity formed on the basis of the aforementioned predetermined pattern can be transferred onto the transparent support In order to produce the antiglare layer having the surface irregularity shape with good precision and good reproducibility, the lithography method is preferable. The lithography method may further include the steps of [1] a first plating step, [2] a polishing step, [3] a photosensitive resin film forming step, [4] an exposure step, [5] An etching step, a photosensitive resin film peeling step, and a second plating step.

Fig. 7 is a diagram schematically showing a preferred example of the first half of the manufacturing method of the mold. Fig. 7 schematically shows a cross section of a mold in each step. Hereinafter, with reference to FIG. 7, each step of the method for producing a mold for producing an antiglare film of the present invention will be described in detail.

[1] First plating process

First, a base material (base material for mold) used in the production of a mold is prepared, and copper is plated on the surface of the base material for a die. As described above, by performing copper plating on the surface of the mold base material, the adhesion and gloss of the chromium plating in the second plating process, which will be described later, can be improved. Copper plating has a high covering property and a strong smoothing action, so that it is possible to form a smooth and glossy surface by filling minute unevenness and voids of the substrate for a mold. Therefore, even if chromium plating is performed in the second plating process described later, by performing the copper plating on the surface of the substrate for a die in this manner, the surface of the chromium plating surface, which is considered to be caused by minute unevenness and voids existing in the substrate The roughness is eliminated and the coating property of the copper plating is high, so that occurrence of fine cracks is reduced. Therefore, even if the surface irregularities based on the predetermined pattern (fine irregularities) are formed on the mold base material molding surface, the irregularities due to the influence of the surface of the base (base material) .

As the copper used for the copper plating in the first plating step, a pure metal of copper may be used, or an alloy (copper alloy) containing copper as a main component may be used. Therefore, " copper " used for copper plating is a concept including copper and a copper alloy. The copper plating may be 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 formed of a metal other than copper.

When the plating layer formed by performing copper plating on the surface of the mold base material is too thin, the influence of the base surface (minute unevenness, voids, cracks, etc.) can not be completely eliminated. Although the upper limit of the thickness of the plating layer is not critical, it is preferably about 500 占 퐉 or less in consideration of cost and the like.

The substrate for a mold is preferably a substrate made of a metal material. 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. The aluminum or the railway referred to herein 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 shape according to the method for producing an antiglare film of the present invention. Specifically, it is selected from a flat substrate, a cylindrical substrate, or a cylindrical (roll-shaped) substrate. In the case of continuously producing the antiglare film of the present invention, the mold preferably has a roll shape. Such a mold is manufactured from a rolled mold base material.

[2] Polishing process

In the subsequent polishing step, the surface (plating layer) of the substrate for copper which has undergone copper plating in the above-described first plating step is polished. In the method for producing a mold used in the method for producing an antiglare film of the present invention, it is preferable that the surface of the mold base is polished to a state close to a mirror surface through the above polishing step. Commercial products such as a flat substrate or a roll substrate used as a substrate for a mold often have been subjected to machining such as cutting or grinding in order to obtain a desired accuracy. As a result, a fine workpiece remains on the surface of the substrate for a die. Therefore, even if a plating (preferably copper plating) layer is formed by the first plating step, the above-mentioned processing mark may remain. Further, even if plating is performed in the first plating step, the surface of the mold base material can not be completely smoothed. That is, even if the steps [3] to [8] to be described later are carried out on the substrate for a mold having such a deep processing mark remaining on the surface, the surface irregularity of the obtained mold surface differs from the surface irregular shape based on the predetermined pattern There may be cases in which irregularities originating from a processing station or the like are included. When an antiglare film is produced by using a mold having an influence of a processing station or the like remaining thereon, optical characteristics such as desired antiglare properties can not be sufficiently exhibited, which may cause unexpected effects.

The polishing method used in the polishing step is not particularly limited, and a polishing method in accordance with the shape and properties of the substrate for a mold to be polished is selected. Specific examples of the polishing method applicable to the polishing step include mechanical polishing, electrolytic polishing, and chemical polishing. Among these, as the mechanical polishing, a super finishing method, a lapping method, a fluid polishing method, and a 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. In this case, the material and shape of the cutting tool can be selected from among cemented carbide, CBN, ceramic, and diamond bite depending on the type of material (metallic material) of the mold base material. From the viewpoint of machining accuracy, desirable. The surface roughness after polishing is preferably 0.1 占 퐉 or less and more preferably 0.05 占 퐉 or less as expressed by a centerline average roughness (Ra) according to JIS B 0601. If the centerline average roughness (Ra) after polishing is larger than 0.1 占 퐉, the surface roughness of the finally obtained metal mold irregularities may be influenced by such surface roughness. The lower limit of the center line average roughness Ra is not particularly limited. Therefore, the lower limit may be set in view of the processing time (polishing time) and the processing cost in the polishing step.

[3] Photosensitive resin film forming process

Next, the photosensitive resin film forming process will be described with reference to Fig.

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 surface 41 of the mold base material 40 subjected to the mirror polishing obtained by the above-mentioned polishing step and heated and dried , And a photosensitive resin film (resist film) are formed. 7 schematically shows a state in which the photosensitive resin film 50 is formed on the surface 41 of the mold base material 40 (Fig. 7 (b)).

As the photosensitive resin, conventionally known photosensitive resins can be used. Those which are already commercially available as a resist can be used as it is, or after purification by 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. Further, 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-block 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, if necessary. Alternatively, a mixture of such additives in a commercially available resist may be used as a photosensitive resin solution have.

In order to apply these photosensitive resin solutions to the surface 41 of the mold base material 40, a solvent most suitable for forming a smoother photosensitive resin film is selected, and a photosensitive resin obtained by dissolving and diluting the photosensitive resin in such a solvent Solution is preferable. Such a solvent is also 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. In the case of using a commercially available resist, 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 mirror polished surface of the mold base material can be carried out by a method such as meniscus coat, fountain coat, dip coat, spin coating, roll coating, wire bar coating, air knife coating, blade coating, , The shape of the mold base material, and the like. The thickness of the photosensitive resin film after the application is preferably in the range of 1 to 10 mu m, more preferably in the range of 6 to 9 mu m, after the drying.

[4] Exposure Process

The subsequent exposure step is a step of transferring the intended pattern onto the photosensitive resin film 50 by exposing the photosensitive resin film 50 formed in the above-described photosensitive resin film forming step. The light source used in the exposure process may be appropriately 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: 365 nm), a semiconductor laser (wavelength: 830 nm, 532 nm, 488 nm, 405 nm), a YAG laser A laser (wavelength: 193 nm), and an F2 excimer laser (wavelength: 157 nm). The exposure method may be a method of collective exposure using a mask corresponding to a target pattern, or a drawing method. As described above, the target pattern has the intensity ratios Γ (0.02) / Γ (0.01) and Γ (0.1) / Γ (0.01) of the spatial frequency of the one-dimensional power spectrum respectively within a predetermined preferable range.

In the method of manufacturing a mold, it is preferable to expose a desired pattern on a photosensitive resin film in a precisely controlled state in order to form the surface relief shape of the mold with higher precision. In order to expose in such a state, it is desirable to draw a desired pattern on the computer as image data and draw (pattern) a pattern based on the image data on the photosensitive resin film by laser light emitted from a computer-controlled laser head Do. When laser drawing is performed, for example, a laser drawing apparatus generally used in the production of a printing plate or the like can be used. Commercially available products of such a laser beam drawing apparatus include, for example, Laser Stream FX (manufactured by Sink Laboratories).

Fig. 7C schematically shows a state in which the pattern is exposed on the photosensitive resin film 50. Fig. When a negative photosensitive resin is contained in the photosensitive resin film 50 (for example, when a negative resist is used as the photosensitive resin solution), the exposed region 51 is exposed to the exposure energy and the crosslinking reaction of the photosensitive resin proceeds And the solubility in a developing solution to be described later is lowered. Therefore, in the developing step, the unexposed area 52 is dissolved by the developing solution, and only the exposed area 51 remains on the substrate surface to become the mask 60. [ On the other hand, in the case where a positive type photosensitive resin is contained in the photosensitive resin film 50 (for example, when a positive resist is used as the photosensitive resin solution), in the exposed region 51, Is likely to dissolve in a developer to be described later. Thus, in the developing process, the exposed area 51 is dissolved by the developing solution, and only the unexposed area 52 remains on the substrate surface 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 by the developing solution, and the exposed area 51 remains on the mold substrate, (60). On the other hand, when the photosensitive resin film 50 contains a positive photosensitive resin, only the exposed area 51 is dissolved by the developing solution, and the unexposed area 52 remains on the mold base material, 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 in the etching process acts as a mask in an etching process described later.

As the developing solution used in the developing process, among those conventionally known, those suitable for the type of the photosensitive resin used can be selected. For example, the developing solution may contain inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; Primary amines such as ethylamine, n-propylamine and the like; Secondary amines such as diethylamine and 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; Alkaline aqueous solutions such as cyclic amines such as pyrrole and piperidine; And organic solvents such as toluene, 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. 7 (d) schematically shows a state after the development process is performed using a negative photosensitive resin. 7D, the unexposed area 52 is dissolved by the developing solution, and only the exposed area 51 remains on the surface of the substrate, and the photosensitive resin film of this area becomes the mask 60. As shown in FIG. Fig. 7 (e) schematically shows a state after the development process is performed using a positive photosensitive resin. In Fig. 7E, the exposed area 51 is dissolved by the developer, and only the unexposed area 52 remains on the substrate surface, and the photosensitive resin film of this area becomes the mask 60. Fig.

[6] Etching process

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

Fig. 8 is a diagram schematically showing a preferable example of the second half of the method for producing a mold. FIG. 8A schematically shows a state after the plating layer in the region where no mask is mainly etched by the etching process. The plating layer under the mask 60 is not etched due to the photosensitive resin film acting as the mask 60 but the etching from the maskless region 45 proceeds with the progress of the etching. Therefore, the plating layer underlying the mask 60 is also etched near the boundary between the masked region 45 and the masked region 45. As described above, the plating on the lower plating layer of the mask 60 is also referred to as side etching in the vicinity of the boundary between the mask 60 and the maskless region 45.

The etching treatment in the etching step is usually carried out by using an etching solution such as a ferric chloride (FeCl ₃ ) solution, a cupric chloride (CuCl ₂ ) solution, or an alkali etching solution (Cu (NH ₃ ) ₄ Cl ₂ ) (Metal surface) in an area where the mask 60 is not mainly present in the surface of the substrate. As the etching treatment, a strong acid such as hydrochloric acid or sulfuric acid may be used as an etching solution. In the case where the plating layer is formed by electrolytic plating, etching treatment is performed using reverse electrolytic etching by applying a potential opposite to that at electrolytic plating You may. Since the surface irregularities formed on the mold base material when the etching treatment is carried out are different depending on the kind of the constituent material (metal material) or plating layer of the mold base material, the type of the photosensitive resin film, the kind of etching treatment in the etching step , It is etched in a substantially isotropic manner from the surface of the substrate for a mold in contact with the etching solution when the etching amount is not more than 10 탆. The etching amount referred to here is the thickness of the plating layer cut by etching.

The etching amount in the etching step is preferably 1 to 10 mu m, more preferably 1 to 6 mu m, and further preferably 1 to 3 mu m. When the etching amount is less than 1 占 퐉, the surface roughness of the mold is hardly formed on the mold and the surface has a substantially flat surface. Therefore, even when the antiglare film is produced using the mold, It is not. The image display device having such an antiglare film does not exhibit sufficient flashing resistance. In addition, when the etching amount is excessively large, the surface of the concavity and convexity of the finally obtained metal concavity and convexity tends to be large. Even when an antiglare film is produced by using the mold, the occurrence of fade can not be sufficiently prevented in the image display device provided with the antiglare film. The etching treatment in the etching step may be performed by one etching treatment or may be performed by dividing the etching treatment into two or more times. In the case where 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 1 to 10 mu m.

[7] Photosensitive resin film peeling step

In the subsequent photosensitive resin film peeling step, the photosensitive resin film remaining on the mold substrate is removed by acting as the mask 60 in the etching step, and the photosensitive resin film remaining on the mold substrate 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 prepared by changing the concentration, pH and the like of the exemplified developer can be used. 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, the method of contacting the peeling liquid and 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.

8B schematically shows a state in which the photosensitive resin film used as the mask 60 in the etching step is completely dissolved and removed by the photosensitive resin film peeling step. The first surface relief shape 46 is formed on the surface of the mold base material by the mask 60 made of the photosensitive resin film and the etching treatment.

[8] Second plating process

The final step in the production of the mold is a second plating step of performing plating (preferably chromium plating described below) on the surface of the substrate for the mold which has undergone the steps of [6] and [7] By performing the second plating process, the surface irregularities 46 of the mold base material can be reduced, and the surface of the mold can be protected by the plating. Hereinafter, dulling of the surface irregularity shape of the mold base material is referred to as " shape reduction. &Quot; 8C, the chromium plating layer 71 is formed on the first surface irregular surface 46 formed by the etching process as described above, whereby the surface irregularity shape is reduced (the mold irregular surface 70) Respectively.

As the plating layer formed by the second plating process, chromium plating is preferable in that it is glossy, has a high hardness, has a small coefficient of friction, and can impart good releasability. Among the chromium plating, chromium plating, which is called so-called glossy chromium plating or decorative chromium plating, which exhibits good glossiness, is particularly preferable. Chrome plating is carried out, but by the conventional electrolytic, and the plating bath, the aqueous solution containing chromic anhydride (CrO ₃₎ and a small amount of sulfuric acid is used as the plating solution. By controlling the current density and the electrolysis time, the thickness of the chromium plating layer can be controlled.

In this manner, plating in the second plating step, preferably chromium plating, is performed to obtain a mold for producing the antiglare film of the present invention. By performing chromium plating on the surface concavo-convex shape on the surface of the mold base material after the etching treatment, the shape can be reduced and a mold with increased surface hardness can be obtained. The largest factor in controlling the degree of shape reduction in this case is the thickness of the chromium plating layer. If the thickness is thin, the degree of shape reduction becomes insufficient, and the antiglare film obtained by using such a mold may cause fretting. On the other hand, if the thickness of the chromium plated layer is excessively large, the degree of the shape reduction becomes too large, and the antiglare film obtained by using such a mold tends to become insufficient in antireflection property. The inventors of the present invention have found that it is effective to manufacture a mold so that the thickness of the chromium plating layer is within a predetermined range in the antiglare film for sufficiently preventing occurrence of fretting and obtaining an image display device having excellent antiglare property. That is, the thickness of the chromium plating layer is preferably in the range of 3 to 10 mu m, more preferably in the range of 4 to 8 mu m.

The chromium plating layer formed in the second plating step is preferably formed so as to have a Vickers hardness of 800 or more, more preferably 1,000 or more. When the Vickers hardness of the chrome plated layer is less than 800, the durability of the mold tends to be lowered when an antiglare film is produced using the mold.

Hereinafter, the optical embossing method 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 specifically described.

In order to continuously produce the antiglaving film of the present invention, when the antiglare film of the present invention is produced by the optical embossing method, the following steps:

[P1] a coating step of coating a coating liquid containing an active energy ray-curable resin on a transparent support continuously transported to form a coating layer, and

A final curing step of irradiating an active energy ray from the side of the transparent support with the surface of the mold pressed on the surface of the [P2] coated layer,

.

Further, when the antiglare film of the present invention is produced by the optical embossing method,

[P3] It is more preferable to include a pre-hardening step after the coating step [P1] and prior to the hardening step [P2], in which both end regions in the width direction of the coated layer are irradiated with active energy rays.

Hereinafter, each step will be described in detail with reference to the drawings. 9 is a diagram schematically showing a preferred example of the production apparatus used in the method for producing an antiglare film of the present invention. The arrows in Fig. 9 indicate the transport direction of the film or the rotation direction of the roll.

[P1] Coating process

In the coating step, a coating solution containing an active energy ray-curable resin is coated on a transparent support to form a coating layer. In the coating process, a coating liquid containing an active energy ray-curable resin composition is applied to the transparent support 81 fed from the feed roll 80, as shown in Fig. 9, in the coating zone 83, for example.

Coating of the coating liquid onto the transparent support 81 can be performed by, for example, 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, a die coating method, .

(Transparent support)

The transparent support 81 may be of a light transmitting type, for example, glass or a plastic film. The plastic film may have appropriate transparency and mechanical strength. Concretely, any of those exemplified as the transparent support already used in the UV embossing method can be used. In order to continuously produce the antiglare film of the present invention by the optical embossing method, those having suitable flexibility are selected.

Various surface treatments may be performed on the surface (coating layer side surface) of the transparent support 81 for the purpose of improving the coating property of the coating liquid and improving the adhesiveness 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 a coating liquid may be coated on the other layer.

In order to improve the adhesion between the transparent support and the polarizing film, the surface of the transparent support (the surface opposite to the coating layer) is subjected to various surface treatments It is preferable to make it hydrophilic. 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 dispersant, 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 esters of polyhydric alcohol and (meth) acrylic acid, urethane (meth) acrylate compounds, polyester (meth) acrylate compounds, epoxy (meth) And polyfunctional polymerizable compounds containing two or more (meth) acryloyl groups such as compounds.

Examples of the polyhydric alcohol include polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, polypropylene glycol, Dihydric alcohols such as diol, 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 esters of polyhydric alcohol and (meth) acrylic acid include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) (Meth) acrylate, trimethylol ethane tri (meth) acrylate, tetramethylol methane tri (meth) acrylate, 1,6-hexanediol di (meth) (Meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, glycerin tri (meth) acrylate, dipentaerythritol tri (Meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, It may include a relay agent.

Examples of the urethane (meth) acrylate compound include an urethane formation reaction product of an organic isocyanate having a plurality of isocyanate groups in one molecule and a (meth) acrylic acid derivative having a hydroxyl group. Examples of the organic isocyanate having a plurality of isocyanate groups in one molecule include hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, naphthalene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate and dicyclohexylmethane diisocyanate. Organic isocyanates having two isocyanate groups in one molecule, and organic isocyanates having three isocyanate groups in one molecule in which isocyanurate modification, adduct modification and biuret modification of these organic isocyanates are exemplified. Examples of the (meth) acrylic acid derivative having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxybutyl (Meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate and pentaerythritol triacrylate.

The polyester (meth) acrylate compound is preferably a polyester (meth) acrylate obtained by reacting a hydroxyl group-containing polyester with (meth) acrylic acid. The hydroxyl group-containing polyester which is preferably used is a hydroxyl group-containing polyester 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, bisphenol A and the like may be mentioned as phenols. Examples of the carboxylic acid include formic acid, acetic acid, butylcarboxylic acid, and benzoic acid. Examples of the compound 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 improving the 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; Adducts of adducts of modified adduct of isophorone diisocyanate and 2-hydroxyethyl (meth) acrylate; And adducts of biuret-modified isophorone diisocyanate and 2-hydroxyethyl (meth) acrylate are preferred. These polyfunctional (meth) acrylate compounds may be used alone or in combination of two or more.

The active energy ray-curable resin may contain a monofunctional (meth) acrylate compound in addition to the above-mentioned multifunctional (meth) acrylate compound. Examples of the monofunctional (meth) acrylate compound include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, (Meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (Meth) acrylate, glycidyl (meth) acrylate, acryloylmorpholine, N-vinylpyrrolidone, tetrahydrofurfuryl (meth) acrylate, cyclohexyl (Meth) acrylate, isobornyl (meth) acrylate, acetyl (meth) acrylate, benzyl (meth) acrylate, 2-ethoxyethyl ) Acrylate, ethyl carbitol (meth) acrylate, phenoxy ) Acrylate, ethylene oxide modified phenoxy (meth) acrylate, propylene oxide (meth) acrylate, nonylphenol (meth) acrylate, ethylene oxide modified (meth) acrylate, propylene oxide modified nonylphenol Acrylate, methoxydiethylene glycol (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, dimethylaminoethyl (meth) acrylate and methoxy triethylene glycol (Meth) acrylates. These compounds may be used alone or in combination of two or more.

Further, 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. The polymerizable oligomer can be obtained, for example, by reacting the polyfunctional (meth) acrylate compound, that is, an ester compound of a polyhydric alcohol and (meth) acrylic acid, a urethane (meth) acrylate compound, a polyester (meth) ) Acrylate, and oligomers such as trimers 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 polyhydric alcohol having at least one (meth) acryloyloxy group . Examples of the polyisocyanate include a polymer of hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate. The polyisocyanate includes at least one (meth) acryloyloxy group- Examples of the alcohol include hydroxyl group-containing (meth) acrylic acid esters obtained by an esterification reaction between a polyhydric alcohol and (meth) acrylic acid. Examples of the polyhydric alcohol include 1,3-butanediol, 1,4- Diol, diethylene glycol, triethylene glycol, neopentyl glycol, polyethylene glycol, polypropylene glycol, trimethylol propane, glycerin, pentaerythritol, dipentaerythritol and the like. In the polyhydric alcohol having at least one (meth) acryloyloxy group, a part of the alcoholic hydroxyl group of the polyhydric alcohol is esterified with (meth) acrylic acid and the alcoholic hydroxyl group remains in the molecule.

Examples of other polymerizable oligomers include polyester (meth) acrylates obtained by reacting a compound having a plurality of carboxyl groups and / or anhydride thereof with a polyhydric alcohol having at least one (meth) acryloyloxy group Oligomers. Examples of the compound having a plurality of carboxyl groups and / or anhydrides thereof include the same ones described in the polyester (meth) acrylate of the polyfunctional (meth) acrylate compound. Examples of the polyvalent alcohol having at least one (meth) acryloyloxy group include the same ones described for the urethane (meth) acrylate oligomer.

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) acrylate ester as an example of a urethane (meth) . The hydroxyl group-containing polyester which is preferably used is a hydroxyl group-containing polyester 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. Examples of the polyhydric alcohol, compound having a plurality of carboxyl groups and / or anhydrides thereof are the same as those described in the polyester (meth) acrylate compound of the polyfunctional (meth) acrylate compound. The hydroxyl group-containing polyether which is preferably used is a hydroxyl group-containing polyether obtained by adding one or more kinds of alkylene oxide and / or epsilon -caprolactone to a 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 which is preferably used include the same ones described in the urethane (meth) acrylate oligomer of the polymerizable oligomer. As the isocyanate, a compound having at least one isocyanate group in the molecule is preferable, and a divalent isocyanate compound such as tolylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate is particularly preferable.

These polymerizable oligomer compounds 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 active energy ray to be applied to the production of the antiglare film of the present invention. When an electron beam is used as the active energy ray, a coating liquid containing no photopolymerization initiator may be used for producing the antiglare film of the present invention.

Examples of the photopolymerization initiator include 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'- 2-chloroacridone, 2-ethyl anthraquinone, benzyl, 9,10-phenanthrenequinone, camphorquinone, methyl phenylglyoxylate, and titanocene compounds can also be used . 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.

The coating liquid may contain a solvent such as 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, Can be used. These solvents may be used alone or in combination of two or more of them if necessary. After the coating, it is necessary to evaporate the organic solvent. Therefore, the boiling point is preferably in the range of 60 占 폚 to 160 占 폚. The saturated vapor pressure at 20 占 폚 is preferably in the range of 0.1 kPa to 20 kPa.

When the coating liquid contains a solvent, it is preferable to provide a drying step after the coating step and before the first curing step, in which the solvent is evaporated and dried. The drying can be performed, for example, by passing a transparent support 81 having a coating layer through the drying zone 84, as in the example shown in Fig. The drying temperature is appropriately selected depending on the type of solvent and 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.

Thus, a laminate in which a transparent support and a coating layer are laminated is formed.

[P2] Curing process

In this step, an active energy ray is irradiated from the side of the transparent support in the state that the surface of the coating layer has a concavo-convex metallic concave surface (molding surface) having a desired surface concavo-convex shape, and the coating layer is cured, Thereby forming a cured resin layer. As a result, the coating layer is hardened, and the surface irregularities on the surface of the mold concavity and convexity are transferred onto the surface of the coating layer. The mold used here is in the form of a roll, which is manufactured by using a roll-shaped mold base material in the previously described mold production method.

9, the coating zone 83 (the drying zone 84 in the case of drying, the active energy ray irradiating unit 86 in the case of performing the pre-hardening step described later) The active energy ray irradiating device 86 such as an ultraviolet ray irradiating device arranged on the transparent support 81 side is used to irradiate the active energy rays As shown in FIG.

First, the rolled mold 87 is pressed onto the surface of the coated layer of the laminate subjected to the curing process by using a compression device such as a nip roll 88, and in this state, the active energy ray irradiating device 86, , An active energy ray is irradiated from the side of the transparent support 81 to cure the coating layer 82. 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 to cause a curing reaction. The use of a nip roll is effective in preventing bubbles from being mixed in between the coating layer of the laminate and the mold. One or more active energy ray irradiating devices may be used.

After irradiating the active energy ray, the laminate is peeled from the mold 87 using the nip roll 89 on the exit side as a fulcrum. The cured coating layer of the obtained transparent support and the cured coating layer becomes an antiglare layer, and the antiglare film of the present invention can be obtained. The obtained antiglare film is usually wound by a film winding device 90. At this time, for the purpose of protecting the antiglare layer, the protective film made of polyethylene terephthalate or polyethylene may be wound on the surface of the antiglare layer through a pressure-sensitive adhesive layer having re-releasability. Although the case where the mold used is roll-shaped is explained here, a mold other than the roll-shaped mold may also be used. Further, after peeling from the mold, additional active energy ray irradiation may be performed.

The active energy ray to be 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 type of active energy ray curable resin contained in the coating solution. Since the electron beam is preferable, and handling is simple and high energy is obtained, ultraviolet rays are particularly preferable (as described above, the UV emboss method is preferable in the optical embossing method).

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

The electron beam may be 50 to 1000 keV, preferably 100 to 1000 keV, emitted from various electron beam accelerators such as a COCORT WALTON type, a Vandegraph type, a resonance type, an insulating core type, a linear type, a Dynamitron type, And an electron beam having an energy of ~ 300 keV.

When the active energy ray is ultraviolet ray, the accumulated amount of light in UVA of ultraviolet ray is preferably 100 mJ / cm2 or more and 3000 mJ / cm2 or less, and more preferably 200 mJ / cm2 or more and 2,000 mJ / cm2 or less. In order to suppress the absorption, the amount of ultraviolet UVV (395 to 445 nm) in the wavelength range including visible light is preferably adjusted so that the amount of accumulated ultraviolet light is preferably adjusted to adjust the amount of irradiation . The amount of accumulated light in the UVV is preferably not less than 100 mJ / cm2 and not more than 3000 mJ / cm2, and more preferably not less than 200 mJ / cm2 and not more than 2000 mJ / cm2. When 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 adheres to a guide roll or the like, which tends to cause process contamination. When the accumulated light quantity exceeds 3000 mJ / cm 2, the transparent support shrinks due to heat radiated from the ultraviolet irradiator to cause wrinkles.

[P3] Pre-hardening process

The present step is a step of preliminarily curing the both end regions by irradiating active energy rays to both end regions in the width direction of the transparent support of the coating layer prior to the curing step. 10 is a cross-sectional view schematically showing a preliminary curing step. In Fig. 10, the end region 82b in the width direction of the coating layer (the direction perpendicular to the transport direction) is a region having a predetermined width from the end portion including the end portion of the coating layer.

By adhering the end regions in advance in the preliminary curing step, the adhesion with the transparent support 81 is further enhanced in the end regions. In the process after the curing step, part of the cured resin is peeled off and falls, Can be prevented. The end region 82b can be, for example, an area of 5 mm or more and 50 mm or less from the end of the coating layer 82.

The irradiation of the active energy ray with respect to the end region of the coating layer can be carried out by irradiating the coating layer 82 passing through the coating zone 83 (in the case of drying, the drying zone 84) Can be performed by irradiating an active energy ray using an active energy ray irradiating device 85 such as an ultraviolet ray irradiating device provided in the vicinity of both end portions on the coating layer 82 side with respect to the transparent support 81 having the above- The active energy ray irradiating device 85 may be provided so as to irradiate an active energy ray to the end region 82b of the coating layer 82 and may be provided on the transparent support 81 side.

The kind of active energy ray and the light source are the same as the present curing process. When the active energy ray is ultraviolet ray, the accumulated amount of light in UVA of ultraviolet ray is preferably 10 mJ / cm2 or more and 400 mJ / cm2 or less, more preferably 50 mJ / cm2 or more and 400 mJ / cm2 or less. The irradiation at 50 mJ / cm 2 or more can more effectively prevent deformation in the final curing step. On the other hand, if it exceeds 400 mJ / cm 2, the curing reaction proceeds excessively, and as a result, the resin peeling may occur at the boundary between the hardened portion and the uncured portion due to the difference in the thickness of the film and the distortion of the internal stress.

[Use of Antiglare Film of the Present Invention]

The antiglare film of the present invention obtained as described above is used in an image display apparatus or the like and is usually used by being bonded to a polarizing film as a visible side protective film of a viewer side polarizing plate (that is, disposed on the surface of an 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 used for an image display apparatus. The image display apparatus provided with the antiglare film of the present invention has satisfactory flicker resistance at a wide viewing angle, and also can prevent both fading and glare from occurring well.

Example

Hereinafter, the present invention will be described in more detail by way of examples. In the examples, "% " and " part " representing the content or amount are based on weight unless otherwise specified.

The evaluation method of the mold or the antiglare film in the following examples is as follows.

[1] Measurement of surface shape of antiglare film

(Inclination angle of the surface relief shape)

The height of the surface of the antiglare film was measured using a three-dimensional microscope PL mu 2300 (manufactured by Sensofar). In order to prevent warping 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 then provided for measurement. The magnification of the objective lens at the time of measurement 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. Based on the obtained measurement data, calculation was made based on the above-described algorithm, and an average value and standard deviation of the inclination angles of the surface irregularities were calculated.

(Power spectrum of the elevation of the surface relief shape)

The height of the surface relief shape of the antiglare layer of the antiglare film as a measurement sample was measured using a three-dimensional microscope PL 占 2300 (manufactured by Sensofar). In order to prevent warpage of the 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 then provided for the measurement. At the time of measurement, the magnification of the objective lens was set to 10 times. The horizontal resolutions? X and? Y were both 1.66 占 퐉 and the measurement area was 1270 占 퐉 占 950 占 퐉. Data of 512 x 512 (850 mu m x 850 mu m in measurement area) are sampled from the center of the obtained measurement data, and the elevation of the surface irregularities (irregular surface irregularities of the antiglare layer) x, y). Subsequently, the two-dimensional function h (x, y) is subjected to discrete Fourier transform to obtain a two-dimensional function H (f _x , f _y ). Two-dimensional function H (f _x, f _y) a two-dimensional power spectral two-dimensional function of the square of the absolute value of I (f _x, f _y) for calculation, and a one-dimensional power spectrum as a function of the distance f from the origin 1 Dimensional function I (f) was calculated. Dimensional elevation function I (f) of the one-dimensional power spectrum calculated from the data of the elevations of the five surface irregularities is measured for each sample, and the average value of the one-dimensional function I (f).

[2] Measurement of Optical Properties of Antiglare Film

(Hayes)

The total haze of the antiglare film was obtained by bonding the antiglare film to the glass substrate on the side opposite to the antiglare layer of the measurement sample by using an optically transparent pressure-sensitive adhesive and measuring the antiglare film bonded to the glass substrate from the glass substrate side Light was incident thereon and measured by a method in accordance with JIS K 7136 using a haze meter " HM-150 " type manufactured by Murakami Shikisai Seiki Seisakusho Co., Ltd. The surface haze was determined by finding the internal haze of the antiglare film,

Surface Haze = Overall Haze - Inner Haze

And the internal haze was subtracted from the total haze. The inner haze was measured in the same manner as the total haze after adhering a triacetylcellulose film having haze of almost zero to the surface of the light-scattering layer of the measurement sample after measuring the total haze with glycerin.

(Transmission sharpness)

The transparency clearance of the antiglare film was measured by a method conforming to JIS K 7105 using a mattimeter "ICM-1DP" manufactured by Suga Shikenki Corporation. Also in this case, in order to prevent warping of the 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 then provided for measurement. In this state, light was incident from the glass substrate side, and measurement was performed. Here, the measured values are the sum of measured values using five types of optical combs having widths of the arm portion and the light portion of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm, respectively.

(Reflection sharpness measured at an incident angle of light of 45 degrees)

The reflectance sharpness of the antiglare film was measured by a method conforming to JIS K 7105 using a "ICM-1DP" measuring instrument of Suga Shikenki Co., Ltd. Also in this case, in order to prevent warpage of the sample, a surface opposite to the antiglare layer of the measurement sample was bonded to the black acrylic substrate using an optically transparent pressure-sensitive adhesive, and then provided for measurement. In this state, light was incident at an angle of 45 DEG from the side of the antiglare layer, and measurement was performed. Here, the measured values are the sum of measured values using four kinds of optical combs having widths of the arm portion and the nominal 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)

The reflectance sharpness of the antiglare film was measured by a method conforming to JIS K 7105 using a "ICM-1DP" measuring instrument of Suga Shikenki Co., Ltd. Also in this case, in order to prevent warpage of the sample, a surface opposite to the antiglare layer of the measurement sample was bonded to the black acrylic substrate using an optically transparent pressure-sensitive adhesive, and then provided for measurement. In this state, light was incident at 60 ° from the side of the antiglare layer, and measurement was performed. Here, the measured values are the sum of measured values using four kinds of optical combs having widths of the arm portion and the nominal portion of 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm, respectively.

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

(Non-visual inspection, evaluation of visual confirmation of visual acuity)

In order to prevent reflection from the back surface of the antiglare film, a surface opposite to the antiglare layer of the measurement sample was adhered to a black acrylic resin plate by an antiglare film and observed visually from the side of the antiglare layer in a bright room with a fluorescent lamp, The degree of non-visualization and the degree of visual desirability were visually confirmed and evaluated. With respect to the non-penetration, the degree of non-contact when the antiglare film was observed from the front side and the degree of non-contact when observed from the direction of 30 ° were evaluated respectively. The non-penetration and the desire were evaluated by the following criteria in three steps of 1 to 3, respectively.

Nonvisual 1: No impression is observed.

2: A small amount of non-visible light is observed.

3: Visible light is clearly observed.

wish 1: No desire is observed.

2: A slight desire is observed.

3: The desire is clearly observed.

(Evaluation of flashing)

The glare was evaluated by the following procedure. That is, first, a photomask having a pattern of unit cells as shown in a plan view in Fig. 11 was prepared. In this figure, a unit cell 100 has a transparent substrate, a claw-shaped chromium shielding pattern 101 having a line width of 10 mu m, and a portion where the chromium shielding pattern 101 is not formed is formed in an opening 102). Here, the dimensions of the unit cells were 211 占 퐉 占 70 占 퐉 (lengthwise in the figure) and thus the dimensions of the openings were 201 占 퐉 占 60 占 퐉 (lengthwise in the drawing). A plurality of unit cells shown are arranged longitudinally and laterally to form a photomask.

12, the chromium light shielding pattern 111 of the photomask 113 is placed on the light box 115 and the antiglare film 110 is adhered to the glass plate 117 as an adhesive agent. Then, as shown in a schematic cross- A sample bonded to the surface of the antiglare layer is placed on the photomask 113. In the light box 115, a light source 116 is disposed. In this state, the sample was visually observed at a position (119), which was about 30 cm away from the sample, and the degree of glare was evaluated in seven steps. Level 1 corresponds to a state in which no glare is observed, Level 7 corresponds to a state in which a strong glow is observed, and Level 4 indicates a state in which a slight glare is observed.

(Evaluation of contrast)

The polarizing plates on both sides of the front and rear sides were peeled off 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 on the back side and the display surface side through the pressure-sensitive adhesive so that the absorption axes thereof coincided with the absorption axes of the original polarizing plates, On the polarizing plate, the antiglare films shown in each of the following examples were 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 luminance in the black display state and the white display state was measured using the 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. The results are shown by the ratio of the contrast measured when the antiglare film was bonded to the contrast measured when the antiglare film was not bonded.

[4] Evaluation of patterns for producing antiglare film

The created 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) are all 2 占 퐉. The obtained two-dimensional function g (x, y) 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 values of the two-dimensional functions G (f _x , f _y ) Dimensional function Γ (f).

≪ Example 1 >

(Production of mold for producing anti-glare film)

A surface of aluminum roll (A6063 by JIS) having a diameter of 300 mm 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 set to be about 200 占 퐉. The copper-plated surface was mirror-polished, 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 A shown in FIG. 13 was repeatedly arranged was exposed on the photosensitive resin film by laser light and developed. Exposure by laser light and development were carried out using Laser Stream FX (manufactured by Sink Laboratories). As the photosensitive resin film, a film containing a positive photosensitive resin was used. Here, the pattern A from the pattern has a distribution of the brightness random, as created by passing a plurality of Gaussian functional of the band-pass filter, the aperture ratio is 45%, and the spatial frequency 0.01 ㎛ of a one-dimensional power ^spectrum strength in a ¹ Γ (0.01) and the spatial frequency 0.02 ㎛ ^- ratio Γ (0.02) / Γ (0.01) of the intensity Γ (0.02) in the ^first is 0.11, and the spatial frequency of 0.01 ㎛ ^- the intensity in the ^first Γ (0.01) and the spatial frequency The ratio Γ (0.1) / Γ (0.01) of the intensity Γ (0.1) at 0.1 μm ^-1 is 10.97.

Thereafter, etching treatment was performed with a cupric chloride solution. The etching amount at that time was set to be 2 占 퐉. The photosensitive resin film was removed from the roll after the etching treatment, and chromium plating processing was performed to prepare a mold A. At this time, the chromium plating thickness was set to be 8 占 퐉.

(Fabrication of antiglare film)

An ultraviolet curable resin composition A was prepared in which the following components were dissolved in ethyl acetate at a solid 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 parts

(The reaction product of hexamethylene diisocyanate and pentaerythritol triacrylate)

Diphenyl (2,4,6-trimethoxybenzoyl) phosphine oxide 5 parts

This ultraviolet ray curable resin composition A was applied on a triacetylcellulose (TAC) film having a thickness of 60 占 퐉 so that the thickness of the coated layer after drying became 5 占 퐉 and dried in a drier set at 60 占 폚 for 3 minutes. The dried film was pressed against the molding surface (surface having the surface irregularities) of the previously obtained mold A with a rubber roll so that the coated layer after drying became the mold side, and was closely contacted. In this state, an antiglare film was prepared from the TAC film side by irradiating light from a high-pressure mercury lamp of intensity 20 mW / cm 2 with a h-line converted light quantity of 200 mJ / cm 2 to cure the coating layer. Thereafter, the resulting antiglare film was peeled off from the mold to prepare a transparent antiglare film A having an antiglare layer on the TAC film.

≪ Example 2 >

The same procedure as in Example 1 was carried out except that the mold B was prepared in the same manner as in the production of the mold A of Example 1 except that the chrome plating thickness in the chrome plating process was set to be 6 탆 and the mold A was replaced with the mold B To prepare an antiglare film. This antiglare film is referred to as antiglare film B.

≪ Example 3 >

A mold C was produced in the same manner as in the production of the mold A of Example 1 except that the chromium plating thickness in the chrome plating process was set to be 4 탆 and the mold A was replaced with the mold C in the same manner as in Example 1 To prepare an antiglare film. This antiglare film is used as the antiglare film C.

≪ Comparative Example 1 &

A mold D was prepared in the same manner as in the production of the mold A of Example 1 except that the thickness of the chromium plating in the chrome plating process was set to 3 탆 and the same mold as in Example 1 To prepare an antiglare film. This antiglare film is referred to as an antiglare film D.

≪ Comparative Example 2 &

A mold E was produced in the same manner as in the production of the mold A in Example 1, except that the pattern in which the pattern B repeatedly arranged as shown in Fig. 14 was repeatedly exposed on the photosensitive resin film by the laser beam. An antiglare film was produced in the same manner as in Example 1. This antiglare film is referred to as an antiglare film E. Here, the pattern B from the pattern has a distribution of the brightness random, as created by passing a plurality of Gaussian functional of the band-pass filter, and the opening ratio is 45.0%, the spatial frequency 0.01 ㎛ of a one-dimensional power ^spectrum strength in a ¹ Γ (0.01) and the spatial frequency 0.02 ㎛ ^- ratio Γ (0.02) / Γ (0.01) of the intensity Γ (0.02) in the ^first is 2.69, the spatial frequency of 0.01 ㎛ ^- the intensity in the ^first Γ (0.01) and the spatial frequency 0.1 ㎛ ^- ratio Γ (0.1) / Γ (0.01 ) of the intensity Γ (0.1) in the ^first is 278.67.

≪ Comparative Example 3 &

The surface of an aluminum roll (A5056 by JIS) having a diameter of 300 mm was mirror-polished and the zirconia bead TZ-SX-17 (Toso Co., Ltd.) was polished on the polished aluminum surface using a blasting machine Blasted with a blast pressure of 0.1 MPa (gauge pressure, the same applies hereinafter) and a bead amount of 8 g / cm 2 (the amount used per 1 cm 2 of the surface area of the roll, hereinafter the same) Unevenness was formed on the roll surface. An electroless nickel plating process was performed on the obtained aluminum roll having the unevenness to prepare a mold F. [ 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 Example 1 except that the mold A was replaced with the mold F. [ This antiglare film is referred to as antiglare film F.

≪ Comparative Example 4 &

A copper ballard plating was performed on the surface of an aluminum roll (A5056 according to JIS) having a diameter of 200 mm. 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. TZ-SX-17 "(manufactured by TOSOH CORPORATION; average particle diameter: 10 μm) was applied to the polished surface of the copper-plated surface by a blast apparatus (manufactured by Fuji Seisakusho Co., Ltd.) 20 탆) was blasted at a blast pressure of 0.05 MPa (gauge pressure, the same applies hereinafter) and a bead usage amount of 6 g / cm ² to form irregularities on the surface of the aluminum roll. The resulting copper-plated aluminum roll with unevenness was chrome-plated to produce a mold G. At this time, the chromium plating thickness was set to be 6 mu m. An antiglare film was produced in the same manner as in Example 1 except that the mold A was replaced with the mold G. This antiglare film is used as the antiglare film G. [

[Evaluation results]

Table 1 shows the results of evaluation of the above-mentioned antiglare film with respect to the above Examples and Comparative Examples.

The antiglare films A to C (Examples 1 to 3) satisfying the requirements of the present invention were excellent in anti-glare properties even in oblique directions, and had a satisfactory effect of suppressing flare and glare even in the case of low haze. On the other hand, the antiglare film D (Comparative Example 1) had a desire. The antiglare film E (Comparative Example 2) had insufficient flicker when observed in an oblique direction. The antiglare film F (Comparative Example 3) was easy to cause glare. The antiglare film G (Comparative Example 4) had insufficient flicker when observed in an oblique direction.

6a, 6b, 6c, 6d: normal vector,
6: average normal vector,
40: mold base material,
41: a surface of a base material (plating layer) for a mold which has undergone a first plating process and a polishing process,
46: a first surface relief shape formed by etching,
50: photosensitive resin film,
60: mask,
70: a surface of a surface irregular surface after chrome plating,
71: chrome plated layer,
80: discharge roll,
81: transparent support,
83: Pottery Zone,
86: active energy ray irradiator,
87: roll mold,
88, 89: nip roll,
90: Film winding device.
Industrial availability
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 of the antiglare film 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 surface irregularity shape is characterized in that the power spectrum of the elevation has the following conditions (1) to (3):
(1) the spatial frequency 0.01 ㎛ ^{- 1} to the intensity I (0.01) or less than 2 ㎛ ⁴ 10 ㎛ ⁴ in;
(2) spatial frequency 0.02 ㎛ ^{- 1} to the intensity I (0.02) or less than 0.1 ㎛ ^{4 4} 1.5 ㎛ in; And
3, the spatial frequency of 0.1 ㎛ ^- intensity I in the ^first (0.1) is not more than 0.0001 ㎛ ⁴ more than 0.01 ㎛ ⁴
Of the antiglare film. The optical information recording medium according to claim 1, wherein the sum Tc of the transmission sharpness measured using five kinds of optical combs having widths of the arm portion and the symbol portion of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm is 375%
The sum Rc (45) of the reflection sharpness measured at the incident angle of 45 [deg.] Of the light using the four types of optical combs having widths of 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm,
Wherein a sum Rc (60) of the reflection sharpness measured at an incident angle of light of 60 占 using the four kinds of optical combs having the widths of the arm portion and the list portion of 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm is 240% or less. .

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