TW201534990A - Anti-glare film - Google Patents

Abstract

An objective of this invention is to provide an anti-glare film, which has an excellent anti-glaring property at a wild observation angel even in low haze, and capable of suppressing the occurrence of whitening and glaring while provided in a picture display device. Provided is an anti-glare film comprising a transparent support body and a finely uneven surface formed thereon, the total haze of the anti-glare film is 0.1% or more and 3% or less, the surface haze is 0.1% or more and 2% or less, a kurtosis Rku of a roughness curve of the uneven surface is 4.9 or less. Intensity ratios of specific two spatial frequencies in a power spectrum of complex amplitudes which is calculated from elevation of the uneven surface and a refraction index of the anti-glare layer fall within predetermined ranges, respectively.

Description

Anti-glare film

The present invention relates to an anti-glare (antiglare) film excellent in anti-glare property.

An image display device such as a liquid crystal display or a plasma display panel, a Brown tube (Cathode Ray Tube: CRT) display, or an organic electroluminescence (EL) display, in order to avoid deterioration of identifiability due to reflection of external light on its display surface, Therefore, an anti-glare film is disposed on the display surface.

The anti-glare film mainly discusses a transparent film having a surface uneven shape. This anti-glare film exhibits anti-glare property by scattering and reflecting external light (scattered light of external light) by surface unevenness and further reducing reflection. However, when the scattered light of the external light is too strong, the overall display surface of the image display device may become white or display a cloudy color, that is, "whitening" may occur. Further, when the pixels of the image display device and the surface unevenness of the anti-glare film are dried, a luminance distribution is generated and it is difficult to see, that is, "glare" also occurs. From the above point of view, it is desirable for the anti-glare film to sufficiently prevent the occurrence of "whitening" and "glare" while ensuring excellent anti-glare properties.

In the case of the anti-glare film, for example, Patent Document 1 discloses that glare does not occur when disposed on a high-definition image display device, and An anti-glare film which sufficiently prevents the occurrence of whitening, and the anti-glare film forms a fine surface uneven shape on a transparent substrate, wherein an average length PSm of any cross-sectional curve of the surface uneven shape is 12 μm or less. The ratio Pa/PSm of the arithmetic mean height Pa to the average length PSm in the cross-sectional curve is 0.005 or more and 0.012 or less, and the ratio of the surface of the surface uneven shape having an inclination angle of 2 or less is 50% or less, and the inclination angle is 6 or less. The ratio of the faces is 90% or more.

In the anti-glare film disclosed in Patent Document 1, the average length PSm in an arbitrary cross-sectional curve is extremely reduced, and the surface unevenness shape having a cycle of 50 μm which is likely to cause glare is eliminated, whereby the glare can be effectively suppressed. However, in the anti-glare film disclosed in Patent Document 1, when the haze is to be made smaller (when the haze is to be set), the display surface of the image display device in which the anti-glare film is disposed is observed from the inclined surface. May cause a decrease in anti-glare properties. Therefore, the anti-glare film disclosed in Patent Document 1 has an improved space in terms of anti-glare property at a wide viewing angle.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2007-187952

An object of the present invention is to provide an anti-glare film which is excellent in anti-glare property at a wide viewing angle at a low haze and which can sufficiently suppress the occurrence of whitening and glare when disposed in an image display device.

The present inventors have intensively studied to solve the above problems, and as a result, have completed the present invention. That is, the present invention provides an anti-glare film comprising a transparent support and an anti-glare layer having a fine surface uneven shape formed on the transparent support; 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, and the kurtosis Rku of the roughness curve of the surface unevenness is 4.9 or less, and the complex amplitude obtained by the following power spectrum calculation method is used. The power spectrum system satisfies all of the following conditions (1) to (3).

(1) The ratio of the spatial frequency of the power spectrum of 0.002 μm ^-1 to the intensity H (0.002) and the spatial frequency of the power spectrum of 0.01 μm ^-1 to the intensity H (0.01) H (0.01) / H (0.002) is 0.02 or more to 0.6; (2) the spatial frequency power spectrum of 0.002μm intensity ^-1 H (0.002) and the spatial frequency power spectrum intensity 0.02μm H (0.02) ^-1 ratio of H (0.02) / H (0.002 ) of 0.005 or more and 0.05 or less; and a ratio of H (0.04 (3) the spatial frequency power spectrum of 0.002μm intensity ^-1 H (0.002) and the spatial frequency power spectrum intensity 0.04μm H (0.04) ^-1 of the in ) / H (0.002) is 0.0005 or more and 0.01 or less.

<Power spectrum calculation method>

(A) averaging the average plane of the virtual plane from the average of the elevation of the surface relief shape; (B) formulating the lowest elevation surface and the highest elevation surface, the minimum elevation surface package a virtual plane having a lowest elevation of the surface relief shape and parallel to the virtual plane of the average surface, the highest elevation surface comprising a point of highest elevation of the surface relief shape and parallel to a virtual plane of the average surface; (C) for self Calculating a plane wave perpendicular to the main normal direction of the lowest elevation surface and emitting a wavelength of 550 nm from the highest elevation surface, and calculating the highest elevation plane based on the elevation of the surface unevenness shape and the refractive index of the antiglare layer The power spectrum of the complex amplitude at the time of the complex amplitude.

Further, in the anti-glare film of the present invention, it is preferable to use the optical clarity of five types of optical combs having a dark portion and a bright portion of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm, respectively. The total Tc is 375% or more; the total of the reflection brightness measured by the optical combs of the dark portion and the bright portion of the 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm widths at an incident angle of 45° of light is used. Rc (45) is 180% or less; the reflection brightness of four types of optical combs having a width of 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm in the dark portion and the bright portion is measured at an incident angle of 60° of light. The total Rc (60) is 240% or less.

According to the present invention, it is possible to provide an anti-glare film which can sufficiently suppress the occurrence of whitening and glare even when it is disposed in an image display device even when it has a wide viewing angle at a low haze.

40‧‧‧Mold base for mold

41‧‧‧ Surface of the substrate for the mold after the first plating step and the grinding step (plating layer)

46‧‧‧The first type of surface relief shape formed by the first etching treatment

47‧‧‧ Surface relief shape shape-passivated by the second etching process

50‧‧‧Photosensitive resin film

60‧‧‧ mask

70‧‧‧ Surface embossed surface after chrome plating

71‧‧‧chrome plating

80‧‧‧Send rolls

81‧‧‧Transparent support

83‧‧‧ Coating area

86‧‧‧Active energy line irradiation device

87‧‧‧roll-shaped mould

88, 89‧‧‧ pinch roller

90‧‧‧ film winding device

103‧‧‧ Lowest elevation surface

104‧‧‧highest elevation

Fig. 1 is a view for simply explaining the elevation of the surface uneven shape of the antiglare film.

Fig. 2 is a view for simply explaining the relationship between the elevation of the surface uneven shape of the antiglare film and the coordinates (x, y).

Fig. 3 is a view for simply explaining the relationship between the elevation h(x, y) of the surface uneven shape of the antiglare film and the elevation reference surface and the highest elevation surface.

Fig. 4 is a view showing a state in which the elevation of the surface uneven shape of the anti-glare film is discretely obtained.

Fig. 5 is a view showing a state in which a one-dimensional power spectrum is calculated from a two-dimensional power spectrum of a complex variable amplitude calculated from an elevation of a surface uneven shape obtained in the form of a discrete function.

Fig. 6 is a graph showing the one-dimensional power spectrum H(f) of the complex amplitude calculated from the elevation of the surface uneven shape of the anti-glare film with respect to the spatial frequency f.

Fig. 7 (a) to (e) are diagrams schematically showing a preferred example of a method (first half) for manufacturing a mold.

Fig. 8 (a) to (d) are diagrams schematically showing a preferred example of a method of manufacturing a mold (the latter half).

Fig. 9 is a view schematically showing a preferred example of a manufacturing apparatus used in the method for producing an anti-glare film of the present invention.

Fig. 10 is a view schematically showing a suitable preliminary hardening step in the method for producing an antiglare film of the present invention.

Fig. 11 is a view schematically showing a unit cell for evaluation of glare.

Fig. 12 is a view schematically showing a glare evaluation device.

Fig. 13 is a view showing a part of the pattern A used in the first embodiment.

Fig. 14 is a view showing a part of the pattern B used in the second embodiment.

Fig. 15 is a view showing a part of the pattern C used in the third embodiment.

Fig. 16 is a view showing a part of the pattern D used in Comparative Example 1.

Fig. 17 is a view showing a part of the pattern E used in Comparative Example 2.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings, but the dimensions and the like shown in the drawings are arbitrarily given for ease of understanding.

The anti-glare film of the present invention is characterized in that the kurtosis Rku of the roughness curve of the surface uneven shape is 4.9 or less, and the spatial frequency of the power spectrum obtained by the power spectrum calculation method is 0.002 μm ^-1 in strength and space. The ratios of the intensities in the frequencies of 0.01 μm ^-1 , 0.02 μm ^-1 and 0.04 μm ^-1 are respectively in the aforementioned ranges.

First, regarding the antiglare film of the present invention, a method of determining the kurtosis Rku of the roughness curve and the power spectrum of the complex amplitude will be described.

[Roughness Rku of Roughness Curve]

The surface roughness of the antiglare layer of the antiglare film of the present invention has a kurtosis Rku of 4.9 in accordance with the method defined in JIS B 0601. the following. The larger the kurtosis Rku is, the more the uneven portion of the surface uneven shape is sharpened, that is, the surface uneven shape has a plurality of regions having steep inclination angles. When an image display device is obtained using the anti-glare film having a large kurtosis Rku, the image display device is whitened. In order to effectively suppress the whitening when the anti-glare film is disposed on the image display device, the inventors found that the anti-glare film having the kurtosis Rku of the roughness curve of 4.9 or less is most effective. In order to obtain an image display device which suppresses whitening more, the kurtosis Rku of the roughness curve of the antiglare film is preferably 4.5 or less, more preferably 4 or less.

The measurement conditions (cut length, evaluation length) when the kurtosis Rku of the roughness curve is measured are appropriately set by the surface roughness Ra obtained in accordance with JIS B0633. In other words, when the surface roughness Ra is more than 0.006 μm and 0.02 μm or less, the cut length is 0.08 mm, the evaluation length is 0.4 mm, and when the surface roughness Ra is more than 0.02 μm and 0.1 μm or less, the cut length is 0.25 mm, and evaluation is performed. When the surface roughness Ra is more than 0.1 μm and 2 μm or less, the cut length is 0.8 mm, the evaluation length is 4 mm, and when the surface roughness Ra is more than 2 μm and 10 μm or less, the cut length is 2.5 mm, and the evaluation length is 12.5mm.

The surface roughness Ra can be measured and determined by the method according to JIS B0601.

[Power spectrum of complex amplitude]

A power spectrum of the complex amplitude calculated from the elevation of the surface uneven shape of the anti-glare film and the refractive index of the anti-glare layer will be described. Fig. 1 is a cross-sectional view schematically showing the surface of an anti-glare film of the present invention. As shown in FIG. 1, the anti-glare film 1 of the present invention has a transparent support 101 and is formed on the transparent support. The anti-glare layer 102 on the object has an anti-glare layer 102 having a surface uneven shape having fine irregularities 2 on the side opposite to the transparent support 101.

Here, the "elevation of the surface unevenness shape" as used in the present invention means that any point P on the surface uneven shape and the minimum elevation surface are along the main normal direction 5 of the anti-glare film of the present invention (the aforementioned lowest elevation surface) The straight line distance from the normal direction. The height of any point of the lowest elevation plane that is virtually determined is 0 μm, and is the reference for determining the elevation of any point on the surface uneven shape, and is shown by the lowest elevation surface 103 in FIG.

Actually, as shown in Fig. 2, the anti-glare film is provided with an anti-glare layer having a fine surface unevenness on a two-dimensional plane. Therefore, as shown in Fig. 2, the elevation of the surface concavo-convex shape can be expressed as a two-dimensional function h(x, x) of the coordinates (x, y) when the rectangular coordinates in the plane of the film are represented by (x, y). y).

The elevation of the surface uneven shape can be obtained from three-dimensional information of the surface shape measured by a device such as a confocal microscope, a dry microscope, or an atomic force microscope (AFM). The horizontal angle resolution required for the measuring machine is preferably 5 μm or less, more preferably 2 μm or less. Further, the vertical angle resolution required for the measuring machine is preferably 0.1 μm or less, more preferably 0.01 μm or less. The non-contact three-dimensional surface shape and the roughness measuring machine suitable for the measurement include New View 5000 series (manufactured by Zygo Corporation), three-dimensional microscope PL μ 2300 (manufactured by Sensofar Co., Ltd.), and the like. The angular resolution of the power spectrum of the elevation is required to be 0.002 μm-1 or less. Therefore, the measurement area is preferably at least 500 μm × 500 μm, more preferably 750 μm × 750 μm or more.

In Fig. 3, the relationship between the elevation h(x, y) of the surface relief shape, the lowest elevation surface 103, and the highest elevation surface 104 is schematically shown. Here, the elevation of the highest elevation surface 104 is set to h _max (μm). In addition, this third figure shows the structure including the highest point of the elevation of the anti-glare film and the profile of the lowest point of the elevation.

The optical path length d(x, y) between the elevation reference plane 103 and the highest elevation plane 104 in the coordinates (x, y) can be expressed by the equation (1) using the two-dimensional function h(x, y) of the elevation.

[Number 1] d ( x , y ) = n _AG h ( x , y ) + n _air [ h _max - h ( x , y )] (1)

Here, n _AG is the refractive index of the antiglare layer, and n _air is the refractive index of air. Then, the refractive index n _{air of the air is} approximated to 1, and the formula (1) can be expressed as in the formula (2).

[Number 2] d ( x , y )=( n _AG -1) h ( x , y )+ h _max (2)

Next, a plane wave of a single wavelength λ transmitted to the main normal direction 5 (the direction perpendicular to the main normal direction of the lowest elevation surface) is incident on the anti-glare layer side from the transparent support side (the lowest elevation surface 103 side) ( The complex amplitude of the plane wave in the case where the highest elevation surface 104 side is emitted will be described. The complex amplitude refers to the portion of the element that does not contain time in the case where the complex number represents the amplitude of the fluctuation. The amplitude of the plane wave of the single wavelength λ can be expressed in plural by the following formula (3).

In the equation (3), A is the maximum amplitude of the plane wave, π is the pi, i is the imaginary unit, z is the z-axis direction (the main normal direction 5) coordinates (the optical path length from the origin), ω is The angular frequency, t is time, and φ ₀ is the initial phase.

In equation (3), the term of the non-dependent time is the complex amplitude. Therefore, the complex amplitude ψ(x, y) in the coordinates (x, y) of the highest elevation surface 104 of the plane wave shown by the equation (3) may be due to the time of the non-dependent (3), in the z It is represented by the following formula (4) in which the optical path length d (x, y) is substituted.

Further, in the equation (4), the maximum amplitude A of the plane wave and the initial phase φ ₀ are not dependent on the coordinates (x, y), and the present invention is intended to define the distribution of the uneven shape on the surface of the coordinate (x, y). The middle is a constant, so in the following, it is assumed that A=1 and φ 0=0. Further, when the above formula (2) is substituted, the complex amplitude ψ(x, y) can be expressed by the following formula (5). Further, in the present invention, λ = 550 nm is used as a reference.

Next, a method of determining the power spectrum of the complex variable amplitude will be described. First, the two-dimensional function Ψ(f _x , f _y ) is obtained from the two-dimensional function ψ(x, y) represented by the equation (5) by the two-dimensional Fourier transform defined by the equation (6). .

Here, f _x and f _y are frequencies in the x direction and the y direction, respectively, and have a reciprocal dimension of length. The square of the absolute value of the obtained two-dimensional function Ψ(fx,fy) is obtained, whereby the two-dimensional power spectrum H(f _x , f _y ) can be obtained from the equation (7).

[ _Equation 7] H ( f _x , f _y )=|Ψ( f _x , f _y )| ² (1)

This two-dimensional power spectrum H(f _x , f _y ) represents the spatial frequency distribution of the complex amplitude calculated from the elevation of the surface uneven shape of the anti-glare film. The anti-glare film is isotropic, so the two-dimensional function H(f _x , f _y ) of the two-dimensional power spectrum representing the complex amplitude can be one-dimensional function dependent only on the distance f from the origin (0, 0). H(f) is indicated. Next, a method of obtaining the one-dimensional function H(f) from the two-dimensional function H(f _x , f _y ) is shown. First, the two-dimensional function H(f _x , f _y ) in the two-dimensional power spectrum of the complex prime amplitude is expressed by a polar coordinate according to the equation (8).

[ _Equation 8] H ( f _x , f _y )= H ( f cos θ, f sin θ)... (8)

Here, θ is the argument in the Fourier space. The one-dimensional function H(f) is obtained by calculating the rotation average of the two-dimensional function H (fcos θ, fsin θ) expressed by the polar coordinates according to the equation (9). One of the dimensional functions obtained from the rotational average of the two-dimensional function H(fx,fy) in the two-dimensional power spectrum of the complex variable amplitude The number H(f) is also referred to below as the one-dimensional power spectrum H(f).

The anti-glare film of the present invention is characterized in that the spatial frequency of the one-dimensional power spectrum H(f) of the complex amplitude calculated from the elevation of the surface concavo-convex shape is 0.002 μm ^-1 of the intensity H (0.002) and the spatial frequency of 0.01 The ratio of the intensity H (0.01) in the μm ^-1 ratio H (0.01) / H (0.002), the intensity H (0.002) and the spatial frequency 0.02 μm ^-1 in the intensity H (0.02) H (0.02) / H (0.002), and the ratio of the intensity H (0.002) to the intensity H (0.04) in the spatial frequency of 0.04 μm ^-1 H (0.04) / H (0.002) are within a specific range.

Hereinafter, a method of obtaining a two-dimensional power spectrum of a complex amplitude calculated from the elevation of the surface uneven shape of the anti-glare film will be more specifically described. The three-dimensional information of the surface shape actually measured by the confocal microscope, the dry microscope, the atomic force microscope, or the like described above is generally a discrete value, that is, obtained by corresponding to the elevation of a plurality of measurement points. Fig. 4 is a view showing a state in which the function h(x, y) indicating the elevation is discretely obtained. As shown in Fig. 4, the Cartesian coordinates in the film plane are represented by (x, y), and on the film projection surface 3, the line divided by Δx in the x-axis direction and the y-axis direction are every △. The line divided by y is indicated by a broken line. In actual measurement, the elevation of the surface uneven shape is in the form of discrete elevation values of the area Δx × Δy divided by each broken line on each film projection surface 3. get.

The number of the obtained elevation values is determined by the measurement range and Δx and Δy. As shown in Fig. 4, the measurement range in the x-axis direction is X=MΔx, and the measurement range in the y-axis direction is set. When Y=NΔy, the number of the obtained elevation values is M×N.

As shown in Fig. 4, the coordinates of the point of interest A on the film projection surface 3 are (m Δx, n Δy). Here, m is 0 or more and M-1 or less, and n is 0 or more. When N-1 or less], the elevation of the point P corresponding to the point A on the film surface can be expressed as h (m Δx, n Δy).

Here, the measurement intervals Δx and Δy are determined by the horizontal resolution of the measuring device, and in order to accurately evaluate the surface unevenness, it is preferable that both Δx and Δy are 5 μm or less, and more preferably 2 μm or less. Further, the measurement ranges X and Y are preferably 500 μm or more, and more preferably 750 μm or more, as described above.

In such a practical measurement, the function indicating the elevation of the surface uneven shape is obtained as a discrete function h(x, y) having M × N values. Therefore, the complex amplitude ψ(x, y) obtained from the two-dimensional function h(x, y) of the surface concavo-convex shape by the equation (5) is also obtained in the form of a discrete function, whereby the amplitude ψ The two-dimensional function Ψ(f _x , f _y ) obtained by the two-dimensional Fourier transform of ( _x , _y ) is also a discrete Fourier transform calculated discretely by equation (6) as in equation (10). The form of the discrete function is obtained.

Here, j in the formula (10) 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, Δfx and Δfy are frequency intervals in the x direction and the y direction, respectively, and are defined by the equations (11) and (12).

The two-dimensional power spectrum H(f _x , f _y ) is obtained by modulating the absolute value of the discrete function Ψ(f _x , f _y ) obtained by the equation (10) as shown in the equation (13).

The two-dimensional power spectrum H(f _x , f _y ) obtained as a discrete function also represents the spatial frequency distribution of the complex amplitude calculated from the elevation of the surface relief shape of the anti-glare film. Moreover, since the anti-glare film is isotropic, the two-dimensional discrete function H(f _x , f _y ) representing the two-dimensional power spectrum of the complex amplitude can also be dependent only on the distance f from the origin (0, 0). The one-dimensional discrete function H(f) is used to represent. When the one-dimensional discrete function H(f) is to be obtained from the two-dimensional discrete function H(f _x , f _y ), the rotation average may be calculated in the same manner as in the equation (9). The discrete rotation averaging of the two-dimensional discrete function H(f _x , f _y ) can be calculated by equation (14). The power spectrum calculation method is to calculate one of the power spectrums represented by the one-dimensional discrete function H(f).

Here, when M≧N, l 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. Δf is the distance between the distances from the origin, and is set to Δf = (Δf _x + Δf _y )/2. Further, Θ(x) is a Heaviside function defined by the formula (15). f _jk is the distance from the origin in (j, k), which is calculated by equation (16).

The calculation shown in the formula (14) is explained using Fig. 5. Since 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 (l-1/2) Δf or more. 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 (l+1/2) Δf or more. Therefore, (f _jk -(l-1/2)Δf)-Θ(f _jk -(l+1/2)Δf) is only (f- _k ) at f _jk When Δf or more and less than (l-1/2) Δf, it is 1, and when it is other than 0, it is 0. Here, f _jk is the distance from the origin O (fx = 0, fy = 0) in the frequency space, so the denominator in equation (14) calculates the distance f _jk from the origin O as (l- 1/2) The number of all the dots (the black dots in Fig. 5) above Δf and not at the position of (l+1/2) Δf. Further, the molecular system in the formula (14) calculates all the dots at a position where the distance f _jk from the origin O is (1 - 1/2) Δf or more and does not reach (l + 1/2) Δf. H (f _x, f _y) of the total value (Fig. 5 black dots of the H (f _x, f _y) of the total value).

In general, the one-dimensional power spectrum obtained by the above method contains the noise in the measurement. When the one-dimensional power spectrum is obtained here, in order to remove the influence of the noise, the elevation of the surface uneven shape at a plurality of positions on the anti-glare film is measured, and one-dimensional power spectrum is obtained from the elevation of the individual surface uneven shape. The average value is preferably used as the one-dimensional power spectrum H(f). The number of positions at which the level of the surface unevenness on the antiglare film is measured is preferably three or more, more preferably five or more.

In Fig. 6, the H(f) of the one-dimensional power spectrum of the complex amplitude calculated from the elevation of the surface relief shape obtained in this manner is shown. The one-dimensional power spectrum H(f) of Fig. 6 is an average of one-dimensional power spectrum obtained by the elevation of the surface unevenness shape at five different positions on the anti-glare film.

The anti-glare film of the present invention is characterized in that the spatial frequency of the one-dimensional power spectrum H(f) of the complex amplitude calculated from the elevation of the surface concavo-convex shape is the intensity H (0.002) and the spatial frequency of 0.01 in the 0.002 μm ^-1 The ratio of the intensity H (0.01) in μm ^-1 to H (0.01) / H (0.002) is 0.02 or more and 0.6 or less, and the ratio of the intensity H (0.002) to the intensity H (0.02) in the spatial frequency of 0.02 μm ^-1 H (0.02) / H (0.002) is 0.005 or more and 0.05 or less, and the ratio of the intensity H (0.002) to the intensity H (0.04) in the spatial frequency of 0.04 μm ^-1 is H (0.04) / H (0.002) is 0.0005 or more and 0.01 the following. Since the one-dimensional power spectrum H(f) is obtained as a discrete function, the intensity H(f ₁ ) in the specific spatial frequency f ₁ is obtained as long as the interpolation calculation is performed as shown in the equation (17). Just fine.

The anti-glare film of the present invention can prevent the occurrence of whitening and glare by setting the intensity ratios in the specific spatial frequencies described above to a predetermined range and adding the haze and reflectance ratios described later. And at the same time, it shows excellent anti-glare properties. In order to exhibit this effect more effectively, the ratio H (0.01) / H (0.002) is preferably 0.02 or more and 0.6 or less, more preferably 0.03 or more and 0.3 or less. Similarly, the ratio H(0.02)/H(0.002) is preferably 0.005 or more and 0.05 or less, more preferably 0.007 or more and 0.04 or less, and more preferably H(0.04)/H(0.002) is 0.0005 or more. Further, it is 0.01 or less, more preferably 0.001 or more and 0.005 or less.

When the ratio H (0.01) / H (0.002) is lower than the above range, the antiglare effect when the antiglare film is observed from the oblique direction (30° or more) is about 100 μm (corresponding to 0.01 μm ^-1 at the spatial frequency). The optical variation of the cycle is small, and the anti-glare property is insufficient. When the ratio H (0.01) / H (0.002) is higher than the above range, the optical fluctuation of the period of about 100 μm is excessively large, and the surface unevenness of the antiglare film is roughened and the haze tends to increase. Not good.

When the ratio H (0.02) / H (0.002) is lower than the above range, the anti-glare effect of the anti-glare film from the oblique direction (10 ° to 30 °) can be improved by 50 μm left-handed (corresponding to 0.02 at the spatial frequency) The optical variation of the period of μm ^-1 ) is small, and the anti-glare property is insufficient. When the ratio H (0.02) / H (0.002) is higher than the above range, the optical variation of the period of about 50 μm becomes excessive and glare occurs.

When the ratio H (0.04) / H (0.002 ) is below the aforementioned range, the anti-glare effect can be improved around the time of observation of the antiglare film of 25 m (corresponding to a positive (0 ° to 10 °) at a spatial frequency of 0.04μm ^- The optical variation of the period of ¹ ) is small, and the anti-glare property is insufficient. When the ratio H (0.04) / H (0.002) is higher than the above range, the scattering caused by the optical fluctuation of a short period of about 25 μm becomes strong, and whitening easily occurs.

[Total haze, surface haze]

The anti-glare film of the present invention has an anti-glare property and prevents whitening, and has a total haze of 0.1% or more and 3% or less with respect to normal incident light, and a surface haze of 0.1% or more and 2% or less. Range. The total haze of the anti-glare film can be measured in accordance with the method shown in JIS K7136. An image display device in which an anti-glare film having a total haze or a surface haze of less than 0.1% is disposed does not exhibit sufficient anti-glare property, and thus is not preferable. Further, when the total haze is higher than 3% or the surface haze is higher than 2%, the anti-glare film is whitened in the image display device in which the anti-glare film is disposed, which is not preferable. The image display device also has a defect that its contrast also becomes insufficient.

Internal haze obtained by subtracting the surface haze from the total haze The lower the better. The image display device in which the anti-glare film having an internal haze of more than 2.5% is disposed has a tendency to be lowered in contrast.

[Through the sharpness Tc, the reflection sharpness Rc (45) and the reflection sharpness Rc (60)]

The anti-glare film of the present invention preferably has a total transmittance Tc of 375% or more obtained under the following measurement conditions. The total amount of sharpness is calculated by measuring the sharpness of the image using a predetermined wide optical comb according to the method of JIS K 7105, and then calculating the total value. Specifically, in the case where the ratio of the width of the dark portion to the bright portion is 1:1, five types of optical combs having a width of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm are used to measure the vividness, respectively. Further, the total value was obtained and set to Tc. When an anti-glare film having a Tc of less than 375% is disposed in a more high-definition image display device, glare may occur easily. The upper limit of Tc is selected from the range of 500% or less of the maximum value. However, when the Tc is too high, an image display device which is easy to reduce the antiglare property from the front is obtained, and therefore it is preferably, for example, 450% or less. .

The reflection brightness Rc (45) measured by the antiglare film of the present invention under incident light having an incident angle of 45 is preferably 180% or less. The reflection sharpness Rc (45) is measured in accordance with the method of JIS K 7105, and the widths of the five types of optical combs are 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm, respectively. The sharpness of the image measured by the four types of optical combs was calculated and found to be Rc (45). When Rc (45) is 180% or less, the image display device in which the anti-glare film is disposed is more excellent in anti-glare property when viewed from the front side and the oblique direction. The lower limit of Rc (45) is not particularly limited, but in order to suppress whitening and glare well The occurrence is preferably, for example, 80% or more.

The reflection brightness Rc (60) measured by the antiglare film of the present invention under incident light having an incident angle of 60 is preferably 240% or less. The reflection sharpness Rc (60) was measured in accordance with JIS K 7105, which is the same as the reflection sharpness Rc (45), except that the incident angle was changed. When Rc (60) is 240% or less, the image display device in which the anti-glare film is disposed is more excellent in anti-glare property when viewed obliquely, which is preferable. The lower limit of Rc (60) is not particularly limited, but is preferably 150% or more in order to suppress whitening and glare more excellently.

[Method for manufacturing anti-glare film]

The anti-glare film of the present invention is produced in the following manner. In the first method, a fine unevenness forming mold which is formed on a surface of a predetermined pattern according to a predetermined pattern is prepared, and the shape of the uneven surface of the mold is transferred to a transparent support, and then the uneven surface is transferred. The method of peeling the transparent support of the shape from the mold. The second method is to prepare a composition containing fine particles, a resin (adhesive), and a solvent, and disperse the fine particles in a resin solution, by applying the composition to a transparent support, and drying it as needed. The coating film (coating film containing fine particles) is cured. In the second method, the coating film thickness and the agglomerated state of the fine particles are adjusted by the composition of the composition or the drying conditions of the coating film, and the fine particles are exposed on the surface of the coating film. The transparent support forms random bumps. From the viewpoint of production stability and production reproducibility of the antiglare film, it is preferred to produce the antiglare film of the present invention by the first method.

Here, the anti-glare film of the present invention will be described in detail. A preferred first method in the manufacturing method.

In order to form an anti-glare layer having a surface uneven shape having the above-described characteristics with good precision, the prepared fine unevenness forming mold (hereinafter sometimes referred to as "mold") is mainly focused. More specifically, the surface uneven shape (hereinafter sometimes referred to as "mold uneven surface") of the mold is formed in accordance with a predetermined pattern, and the predetermined pattern is preferably a spatial frequency of the one-dimensional power spectrum of 0.002 μm ^-1 . The ratio Γ(0.01)/Γ(0.002) of the strength Γ(0.002) to the strength Γ(0.01) in the spatial frequency of 0.01 μm ^-1 is 1.5 or more and 6 or less, and the intensity in the spatial frequency is 0.002 μm ^-1 ( 0.002) with the spatial frequency intensity 0.02μm Γ (0.02) ^-1 of the ratio Γ (0.02) / Γ (0.002 ) of 5 or more and 0.3 or less, the spatial frequency intensity 0.002μm Γ (0.002) ^-1 in the spatial frequency The ratio Γ(0.04) / Γ(0.002) of the strength Γ (0.04) in 0.04 μm ^-1 is 3 or more and 13 or less. Here, the "pattern" means an image data for forming a surface uneven shape of an anti-glare layer of an anti-glare film, or a mask having a light-transmitting portion and a light-shielding portion, and the like, hereinafter abbreviated as "pattern""."

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

A method of finding a two-dimensional power spectrum of a pattern when the pattern is image data is displayed, for example. First, the image data is transformed into a second-order binary image data, and then the gradation is displayed as a two-dimensional function g(x, y). The obtained two-dimensional function g(x, y) is Fourier transformed into a two-dimensional function G(f _x , f _y ) as shown in the following formula (18), and is obtained as shown in the following formula (19). The square of the absolute value of the two-dimensional function G(f _x , f _y ) is used to obtain the two-dimensional power spectrum Γ (f _x , f _y ). Here, x and y represent right angle coordinates in the plane of the image data. Also, f _x and f _y represents the frequency in the x direction and the y direction, respectively, and has the reciprocal dimension of the length.

In the formula (18), π is a pi, and i is an imaginary unit.

[19] Γ( f _x , f _y )=| G ( f _x , f _y )| ² (19)

This two-dimensional power spectrum f(f _x , f _y ) represents the spatial frequency distribution of the pattern. Usually, the antiglare film is required to be isotropic, and the pattern for producing the antiglare film of the present invention is also 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 dimensional function Γ(f) corresponding only to the distance f from the origin (0, 0). Next, a method of obtaining the one-dimensional function Γ(f) from the two-dimensional function Γ(f _x , f _y ) will be described. First, as shown in the equation (20), the two-dimensional function Γ(f _x , f _y ) of the two-dimensional power spectrum of the tone of the pattern is represented by a polar coordinate.

[Number 20] Γ( f _x , f _y )=Γ( f cos θ, f sin θ)...(20)

Here, θ is the argument in the Fourier space. The one-dimensional function Γ(f) can be obtained by calculating the rotational average of the two-dimensional function Γ (fcos θ, fsin θ) expressed by the polar coordinates as in the equation (21). One dimensional function Γ(f) is obtained from the rotational average of the two-dimensional function Γ(f _x , f _y ) of the two-dimensional power spectrum belonging to the gradation of the pattern, which is hereinafter referred to as a one-dimensional power spectrum Γ(f) ).

In order to obtain good accuracy of the antiglare film of the present invention, the preferred frequency 0.002μm strength Γ (0.002) ^-1 in the one-dimensional power spectrum of the spatial pattern of the intensity of the spatial frequency 0.01μm Γ (0.01) ^-1 of the in ratio Γ (0.02) ratio Γ (0.01) / Γ (0.002 ) of 1.5 or more and 6 or less, the spatial frequency intensity Γ (0.002) in the spatial frequency intensity 0.002μm ^-1 Γ (0.02) of the of 0.02μm ^-1 ratio Γ (0.04) / Γ (0.002 ) /Γ(0.002) is 0.3 or more and 5 or less, in the spatial frequency intensity Gamma] 0.002μm ^-1 (0.002) and the spatial frequency intensity Γ (0.04) of the of 0.04μm ^-1 It is 3 or more and 13 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. At this time, it is only necessary to calculate the two-dimensional power spectrum by discrete Fourier transform. The one-dimensional power spectrum of the pattern is derived from the two-dimensional power spectrum of the pattern in the same manner.

The kurtosis Rku of the roughness curve of the surface uneven shape of the anti-glare film is 4.9 or less. In order to manufacture the anti-glare film of the present invention, the average value of the two-dimensional function g(x, y) is preferably a two-dimensional function g. The difference between the maximum value of (x, y) and the minimum value of the two-dimensional function g(x, y) is 35 to 65%. When the concave-convex surface of the mold is manufactured by lithography, the two-dimensional function g(x, y) becomes the aperture ratio of the pattern. Regarding the manufacture of the concave-convex surface of the mold by the lithography process, the aperture ratio of the pattern referred to herein is first defined. The aperture ratio when the photoresist used in the lithography process is a posi-resist means the total surface of the coating film when the image of the coating film of the positive photoresist is drawn. The ratio of the area of the area exposed. On the other hand, the aperture ratio when the photoresist used in the lithography process is a negative photoresist means that when the image film of the negative photoresist is imaged, the total surface of the film is relative to the film. The ratio of areas of the area that have not been exposed. The lithography process is an aperture ratio at the time of overall exposure, and means a ratio of a light-transmitting portion having a light-transmitting portion and a mask of the light-shielding portion. When the aperture ratio of the pattern is too small or too large, the convex portion or the concave portion of the fine uneven surface formed on the mold becomes loose, and as a result, the unevenness of the surface uneven shape of the obtained anti-glare film becomes loose, and the kurtosis tends to increase. The inventors have found that when the antiglare film is produced by a mold obtained by setting the aperture ratio of the pattern to the above range, it is easy to set the kurtosis Rku of the roughness curve to 4.9 or less.

The anti-glare film of the present invention can set the intensity ratio of the one-dimensional power spectrum of the pattern to Γ(0.01)/Γ(0.002), Γ(0.02)/Γ(0.002), and Γ(0.04)/Γ(0.002), respectively. The required mold is produced in the above range, and the mold is further produced by the above-described first method.

In order to create a pattern having such a power ratio of one-dimensional power spectrum, a pattern prepared by randomly arranging dots or a random brightness determined by random numbers or having a gradation determined by a computer may be prepared in advance. A pattern of distribution (preparation pattern) from which components of a particular spatial frequency range are removed. In the component removal of the specific spatial frequency range, the preliminary pattern may be passed through a band pass filter.

In order to manufacture an anti-glare film having an anti-glare layer formed with a surface uneven shape according to a predetermined pattern, a mold having a concave-convex surface for transferring a surface uneven shape formed according to the predetermined pattern to a transparent support is manufactured. The first method described above using the mold is characterized by An embossing method for forming an anti-glare layer on a transparent support.

Examples of the embossing method include a photo embossing method using a photocurable resin, a hot embossing method using a thermoplastic resin, and the like. Among them, from the viewpoint of production productivity, a photo embossing method is preferred.

In the photoembossing method, a photocurable resin layer is formed on a transparent support (the surface of the transparent support), and the photocurable resin layer is pressed while being pressed against the uneven surface of the mold of the mold to thereby mold the mold. A method of transferring the shape of the uneven surface to the photocurable resin layer. Specifically, the photocurable resin layer formed by applying a photocurable resin to the transparent support is adhered to the uneven surface of the mold, and in this state, light is irradiated from the side of the transparent support (the light system is hardenable) The photocurable resin (the photocurable resin contained in the photocurable resin layer) is cured, and then the transparent support formed of the cured photocurable resin layer is peeled off from the mold. In the antiglare film obtained by such a production method, the cured photocurable resin layer serves as an antiglare layer. In addition, it is preferable that the photocurable resin is an ultraviolet curable resin, and when the ultraviolet curable resin is used, ultraviolet rays are used for the light to be irradiated (the ultraviolet curable resin is used as the photocurable resin). The embossing method is hereinafter referred to as "UV embossing method". In order to manufacture an anti-glare film integrated with a polarizing film, a polarizing film is used as a transparent support, and in the embossing method described here, the transparent support may be replaced by a polarizing film.

The type of the ultraviolet curable resin used in the UV embossing method is not particularly limited, and may be appropriately used from commercially available resins depending on the type of the transparent support to be used or the type of the ultraviolet ray. The ultraviolet curable tree The grease conceptually includes photopolymerizable monomers (polyfunctional monomers), oligomers and polymers produced by ultraviolet irradiation, and mixtures thereof. Moreover, depending on the kind of the ultraviolet curable resin, a suitably selected photoinitiator can be used in combination, whereby a resin which can be cured under visible light longer than the ultraviolet wavelength can be used. A description of suitable examples of the ultraviolet curable resin and the like will be described later.

For the transparent support used in the UV embossing method, for example, a glass or a plastic film or the like can be used. The plastic film can be used as long as it has appropriate transparency and mechanical strength. Specific examples thereof include a cellulose acetate resin such as TAC (triacetate cellulose); an acrylic resin; a polycarbonate resin; a polyester resin such as polyethylene terephthalate; and polyethylene. A transparent resin film such as a polyolefin resin such as 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 μm, preferably 10 to 100 μm, more preferably 10 to 60 μm. When the thickness of the transparent support is within this range, an anti-glare film having sufficient mechanical strength tends to be obtained, and an image display device including the anti-glare film is more difficult to cause glare.

On the other hand, in the hot embossing method, the transparent resin film formed of the thermoplastic resin is pressed against the uneven surface of the mold while being heated and softened, and the surface uneven shape of the uneven surface of the mold is transferred to the transparent resin film. The method. The transparent resin film used in the hot embossing method may be any one that is substantially transparent to light, and specifically, those which are used as a transparent resin film as listed in the UV embossing method.

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

Regarding the manufacturing method of the mold, the molding surface of the mold is a mold which can transfer a surface uneven shape formed according to the predetermined pattern described above to a transparent support (an anti-glare layer which can form a surface uneven shape formed according to a predetermined pattern) The range of the uneven surface is not particularly limited, but in order to manufacture the anti-glare layer having the uneven shape of the surface with high precision and preferable reproducibility, a lithography process is preferred. Furthermore, the lithography process preferably comprises [1] a first plating step, [2] a first polishing step, [3] a photosensitive resin film forming step, [4] an exposure step, and [5] a developing step. [6] First etching step, [7] photosensitive resin film peeling step, [8] second etching step, [9] second plating step, and [10] second polishing step.

Fig. 7 is a view schematically showing a preferred example of the first half of the method for manufacturing a mold. Fig. 7 is a schematic view showing a section of a mold at each step. Hereinafter, each step in the method for producing a mold for producing an anti-glare film of the present invention will be described in detail with reference to FIG.

[1] 1st plating step

First, a substrate (a substrate for a mold) used for manufacturing a mold is prepared, and copper plating is applied to the surface of the substrate for the mold. In this manner, by applying copper plating to the surface of the substrate for a mold, the adhesion and gloss of chrome plating in the second plating step to be described later can be improved. Since copper plating has a high coating property or a smoothing effect, a small unevenness or looseness of a substrate for a mold is buried to form a flat and shiny surface. Therefore, by applying copper plating to the surface of the substrate for a mold in such a manner, even if chrome plating is applied in the second plating step to be described later, it is possible to eliminate the occurrence of minute irregularities or voids existing in the substrate. Caused by The chrome surface is rough. Therefore, even if the surface unevenness shape (fine uneven surface shape) according to the predetermined pattern is formed on the base molding surface of the mold, the influence of the surface of the base (substrate for the mold) such as minute irregularities or voids can be sufficiently prevented. Offset.

For the copper used for copper plating in the first plating step, a pure copper metal or an alloy containing copper as a main component (copper alloy) can be used. Therefore, the "copper" used in copper plating conceptually includes copper and copper alloys. The copper plating may be electrolytic plating or electroless plating, but it is preferable to use electrolytic plating for the copper plating of the first plating step. Further, the preferred plating layer in the first plating step is not limited to a copper plating layer, but may be a plating layer composed of a copper plating layer and a metal other than copper.

When the plating layer formed by plating copper on the surface of the substrate for a mold is too thin, the influence of the surface of the substrate (fine irregularities, voids, cracks, and the like) cannot be completely excluded, so the thickness is preferably 50 μm or more. . The upper limit of the thickness of the plating layer is not limited, but it is preferably about 500 μm or less in consideration of cost and the like.

The substrate for the mold is preferably a substrate composed of a metal material. Further, from the viewpoint of cost, the material of the metal material is preferably aluminum, iron or the like. Further, in view of the convenience of the treatment of the substrate for a mold, it is particularly preferable that the substrate composed of lightweight aluminum is used as a substrate for a mold. Further, the aluminum or iron referred to herein does not need to be each a pure metal, and may be an alloy mainly composed of aluminum or iron.

The shape of the substrate for a mold depends on the method for producing the anti-glare film of the present invention, as long as it is a suitable shape. Specifically, it can be flat A substrate, a cylindrical substrate, or a cylindrical (roller) substrate or the like is selected. When the antiglare film of the present invention is continuously produced, the mold is preferably a roll shape. Such a mold is produced from a substrate for a mold having a roll shape.

[2] First grinding step

Next, in the first polishing step, the surface (plating layer) of the substrate for a mold to which copper plating is applied in the above-described first plating step is polished. In the method for producing a mold used in the method for producing an anti-glare film of the present invention, it is preferred that the surface of the substrate for a mold is polished to a state close to the mirror surface through the first polishing step. As a commercially available product of a flat substrate or a roll-shaped base material used for a substrate for a mold, in order to achieve the desired precision, most of the machining is performed by cutting or grinding, and thus the surface of the substrate for the mold is used. Remaining fine processing marks. Therefore, even if a plating (preferably copper plating) layer is formed through the first plating step, the processing marks may remain. Moreover, even if the plating in the first plating step is applied, the surface of the substrate for the mold is not necessarily completely smoothed. In other words, for the substrate for a mold having a surface on which such a deep processing mark or the like is left, even if the steps [3] to [10] described later are applied, the surface unevenness of the surface of the obtained mold is determined according to the predetermined pattern. The surface unevenness shape may be different or may include irregularities such as processing marks. When an anti-glare film is produced by using a mold which is affected by the processing target or the like, the optical characteristics such as the anti-glare property of the target are not sufficiently exhibited, and there is a fear that the effect cannot be expected.

The polishing method used in the first polishing step is not particularly limited, and a polishing method depending on the shape and properties of the substrate for a mold to be polished may be selected. Specific examples of the polishing method applicable to the first polishing step include a mechanical polishing method, an electrolytic polishing method, and a chemical polishing method. Among these, the mechanical polishing method may use any of superfinishing, polishing, fluid milling, and polishing wheel polishing. Further, in the polishing step, mirror cutting may be performed by using a cutting tool to form a mirror surface on the surface of the substrate for a mold. The material and shape of the cutting tool at this time depend on the type of the material (metal material) of the base material for the mold, and it is possible to use a super-hard turning tool, a CBN turning tool, a ceramic turning tool, a diamond turning tool, etc., but from the viewpoint of machining accuracy. In view of this, it is better to use a diamond turning tool. The surface roughness after polishing is expressed in accordance with JIS B 0601 center line average roughness Ra, preferably 0.1 μm or less, more preferably 0.05 μm or less. When the center line average roughness Ra after polishing is more than 0.1 μm, the surface roughness of the mold of the finally obtained mold may be left to the influence of the surface roughness. Further, the lower limit of the center line average roughness Ra is not particularly limited. Therefore, the lower limit value may be determined from the viewpoint of the processing time (polishing time) or the processing cost in the first polishing step.

[3] Photosensitive resin film forming step

Next, a photosensitive resin film forming step will be described with reference to Fig. 7 .

In the photosensitive resin film forming step, the surface 41 of the mold substrate 40 subjected to mirror polishing obtained by the above-described first polishing step is coated with a solution in which a photosensitive resin is dissolved in a solvent (photosensitive) Resin solution) and by heating. It is dried to form a photosensitive resin film (photoresist film). In the seventh embodiment, a state in which the photosensitive resin film 50 is formed on the surface 41 of the substrate 40 for a mold is schematically shown (Fig. 7(b)).

As the photosensitive resin, a conventionally known photosensitive resin or a commercially available photoresist can be directly or, if necessary, purified by filtration or the like. Use it again. For example, in the case of a photosensitive resin having a negative type in which the photosensitive portion is hardened, a monomer or prepolymer which is used for a (meth) acrylate having an acrylonitrile group or a methacryl group in the molecule, and a double A mixture of bisazide and diene gum, a poly(vinyl cinnamate) compound, or the like. In addition, a phenol resin-based or novolak resin-based resin may be used as the positive-type photosensitive resin having a property in which the photosensitive portion is eluted by development and the photosensitive portion is not left. Among the positive or negative photosensitive resins, a positive photoresist or a negative photoresist can be easily obtained from the market. Further, the photosensitive resin solution may be blended with various additives such as a sensitizer, a development catalyst, an adhesion modifier, and a coatability improver, and may be mixed with a commercially available photoresist. It is used as a photosensitive resin solution.

In order to apply such a photosensitive resin solution to the surface 41 of the substrate 40 for a mold, the most suitable solvent is selected before forming a smoother photosensitive resin film, and the photosensitive resin is dissolved and diluted. A photosensitive resin solution obtained by the solvent is preferred. Such a solvent is selected depending on the type of the photosensitive resin and its solubility. Specifically, it is selected, for example, from a cellosolve solvent, a propylene glycol solvent, an ester solvent, an alcohol solvent, a ketone solvent, a highly polar solvent, or the like. When a commercially available photoresist is used, the most suitable photoresist can be selected and used as a photosensitive resin solution depending on the kind of the solvent contained in the photoresist or an appropriate preliminary experiment.

A method of coating a photosensitive resin solution on a mirror-polished surface of a substrate for a mold, which can be coated by a liquid concave surface, spray coated, or Among known methods such as dip coating, spin coating, roller coating, coating bar coating, pneumatic blade coating, blade coating, curtain coating, and ring coating, The shape of the substrate for the mold is selected. The thickness of the photosensitive resin film after application is preferably in the range of 1 to 10 μm after drying, and more preferably in the range of 6 to 9 μm.

[4] Exposure step

Then, the exposure step is a step of transferring the target pattern to 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 step may be appropriately selected by blending the photosensitive wavelength or sensitivity of the photosensitive resin contained in the photosensitive resin film, and for example, a g-line (wavelength: 436 nm) and an h-line (wavelength: 405 nm) of a high-pressure mercury lamp can be used. ), or i-line (wavelength: 365 nm), semiconductor laser (wavelength: 830 nm, 532 nm, 488 nm, 405 nm, etc.), YAG laser (wavelength: 1064 nm), KrF excimer laser (wavelength: 248 nm), ArF excimer Laser (wavelength: 193 nm), F2 excimer laser (wavelength: 157 nm), and the like. The exposure mode is a method of overall exposure using a mask corresponding to the target pattern, and may also be a drawing mode. In addition, the standard pattern is the same as explained, and the intensity ratio of the spatial frequency of the one-dimensional power spectrum is 0.01(0.01)/Γ(0.002), Γ(0.02)/Γ(0.002), and Γ(0.04)/Γ( 0.002) Set in the preferred range.

In the method for producing a mold, in order to form the uneven shape of the surface of the mold with better precision, it is preferable to expose the target pattern on the photosensitive resin film in a state of being precisely controlled. In order to expose in this state, the target pattern is created on the computer as image data, and by It is preferable that the pattern of the image data is drawn (laser drawing) on the photosensitive resin film from the laser light emitted from the laser light controlled by the computer. At the time of laser drawing, a laser drawing device which is widely used, such as printing plate production, can be used. A commercially available product of such a laser drawing device is, for example, Laser Stream FX (manufactured by Think Laboratory).

Fig. 7(c) is a view schematically showing a state in which the photosensitive resin film 50 is exposed by a pattern. When the photosensitive resin film 50 contains a negative photosensitive resin (for example, when a negative photoresist is used as the photosensitive resin solution), the exposed region 51 is subjected to exposure energy to carry out a crosslinking reaction of the photosensitive resin, which will be described later. The solubility of the developer is lowered. Therefore, the unexposed area 52 in the developing step is dissolved by the developer, and remains only on the surface of the substrate on the exposed region 51, and becomes the mask 60. On the other hand, when the photosensitive resin film 50 contains a positive photosensitive resin (for example, when a positive photoresist is used as the photosensitive resin solution), the photosensitive resin is cut by exposure energy in the exposed region 51. The combination or the like is easily dissolved in the developer described later. Therefore, the exposed region 51 in the developing step is dissolved by the developer, and only the unexposed region 52 remains on the surface of the substrate to become the mask 60.

[5] Development step

In the development step, when the photosensitive resin film 50 contains a negative photosensitive resin, the unexposed region 52 is dissolved by the developer, and the exposed region 51 remains on the substrate for the mold to form a mask. 60. On the other hand, when the photosensitive resin film 50 contains a positive photosensitive resin, only the exposed region 51 is dissolved by the developer, and the unexposed region 52 remains in the mold. The mask 60 is formed on the substrate. In the first etching step, the photosensitive resin film remaining on the substrate for a mold is used as a mask in a first etching step to be described later, in a substrate for a mold having a predetermined pattern as a photosensitive resin film. effect.

Regarding the developer used in the development step, depending on the type of the photosensitive resin to be used, it is possible to select an appropriate one among those conventionally known. For example, the developing solution may, for example, be sodium hydroxide, potassium hydroxide, sodium carbonate, sodium citrate, sodium methyl citrate or an inorganic base such as ammonia; the first amine such as ethylamine or n-propylamine; diethylamine; a second amine like di-n-butylamine; a third amine like triethylamine or methyldiethylamine; an alcohol amine like dimethylethanolamine or triethanolamine; tetramethylammonium hydroxide, tetraethyl a fourth-order ammonium compound such as ammonium hydroxide or trimethylhydroxyethylammonium hydroxide; an alkaline aqueous solution in which a cyclic amine such as pyrrole or piperidine is dissolved; an organic solvent such as xylene or toluene.

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

In the seventh diagram (d), the state after the development step using the negative type as the photosensitive resin is schematically shown. The unexposed region 52 in Fig. 7(d) is dissolved by the developer, and only the exposed region 51 remains on the surface of the substrate, and the photosensitive resin film in this region serves as the mask 60. In Fig. 7(e), the state after the development step is performed using a positive type as a photosensitive resin. The exposed region 51 in Fig. 7(e) is dissolved by the developer, and only the unexposed region 52 remains on the surface of the substrate, and the photosensitive resin film in this region serves as the mask 60.

[6] First etching step

The first etching step is performed after the development step described above, and the photosensitive resin film remaining on the surface of the substrate for the mold is used as a mask, and the surface of the substrate for the mold is mainly located in the unmasked surface. The step of etching the plating layer of the region.

Fig. 8 is a view schematically showing a preferred example of the latter half of the method for manufacturing a mold. In Fig. 8(a), the state in which the plating layer of the unmasked region is mainly etched by the etching step is schematically shown. The plating layer on the lower portion of the mask 60 is not etched by the photosensitive resin film as the mask 60, but is etched from the maskless region 45 while being etched. Therefore, the plating layer located at the lower portion of the mask 60 near the boundary between the region having the mask 60 and the unmasked region 45 is also etched. As such, the state in which the plating layer of the lower portion of the mask 60 near the boundary between the region having the mask 60 and the unmasked region 45 is also etched is referred to as side etching.

In the etching treatment in the first etching step, an etching solution such as a second iron (FeCl 3 ) solution, a second copper (CuCl ₂ ) solution, or an alkaline etching solution (Cu(NH ₃ ) ₄ Cl ₂ ) is usually used. Among the surfaces of the substrate for a mold, it is mainly carried out by causing the plating layer (metal surface) of the field without the mask 60 to rot. In the etching treatment, a strong acid such as hydrochloric acid or sulfuric acid may be used as an etching solution, and when the plating layer is formed by electrolytic plating, the potential opposite to that at the time of electrolytic plating may be used. Etching is performed by reverse electrolytic etching. The surface unevenness shape formed by the base material for the mold when the etching treatment is applied is based on the constituent material (metal material) of the mold base material, the type of the plating layer, the type of the photosensitive resin film, and the etching step. The type of the etching treatment differs depending on the type of the etching treatment, and it is not possible to unilaterally etch the surface of the substrate for the mold which is in contact with the etching liquid when the etching amount is 10 μm or less. The amount of etching referred to herein means the thickness of the plating layer which is reduced by etching.

The etching amount in the first etching step is preferably from 1 to 20 μm, more preferably from 3 to 10 μm, still more preferably from 5 to 8 μm. When the etching amount is less than 1 μm, the surface has substantially no surface unevenness, and the surface has a substantially flat surface. Therefore, even if the mold is used to produce an anti-glare film, the anti-glare film is substantially free of surface irregularities. . An image display device in which such an anti-glare film is disposed may fail to display sufficient anti-glare properties. Further, when the etching amount is too large, the resulting uneven surface of the mold tends to have a large difference in unevenness. Even if the anti-glare film is manufactured using the mold, the image display device including the anti-glare cannot sufficiently prevent the occurrence of whitening. The etching treatment in the etching step can be performed by one etching treatment, or the etching treatment can be carried out by dividing the etching treatment into two or more times. When the etching treatment is divided into two or more times, the total amount of etching in the etching treatment of two or more times is preferably from 1 to 20 μm.

[7] Photosensitive resin film peeling step

Then, in the photosensitive resin film peeling step, the photosensitive resin film remaining as a mask 60 in the first etching step and remaining on the substrate for the mold is removed, and the step is performed in the mold. It is preferred to completely remove the photosensitive resin film remaining on the substrate. It is preferable to use a peeling liquid to dissolve the photosensitive resin film in the photosensitive resin film peeling step. In the case of a stripping solution, it is possible to change its concentration by using the developer as a developer. It is prepared by pH or the like. Alternatively, the photosensitive resin film is peeled off by using the same developer as that used in the developing step, and by changing the temperature or the immersion time to be different from the development step. In the photosensitive resin film peeling step, the contact method (peeling method) of the peeling liquid and the substrate for a mold is not particularly limited, and immersion peeling, spray peeling, brush peeling, ultrasonic peeling, or the like can be used.

(b) of FIG. 8 is a view schematically showing a state in which the photosensitive resin film used as the mask 60 in the first etching treatment is completely dissolved and removed by the photosensitive resin film peeling step. The first surface uneven shape 46 is formed on the surface of the substrate for a mold by the mask 60 formed of the photosensitive resin film and the etching treatment.

[8] Second etching step

The second etching step is a step of passivating the first surface uneven shape 46 formed in the first etching step by a further etching treatment (second etching treatment). In the first surface uneven shape 46 formed by the first etching process, the portion having a steep surface inclination disappears (hereinafter, the surface is inclined steeply among the surface unevenness shapes) Partial passivation is called "shape passivation"). In Fig. 8(c), the first surface uneven shape 46 of the mold base material 40 is shape-passivated by the second etching treatment, whereby the portion whose surface inclination is steep is passivated, and the display is gentle. The state of the second surface uneven shape 47 whose surface is inclined. The mold obtained by performing the second etching treatment in such a manner has an effect of improving the optical characteristics of the anti-glare film of the present invention produced by using the mold.

In the second etching treatment in the second etching step, an etching treatment or a reverse electrolytic etching using the same etching liquid as in the first etching step may be used. The degree of shape passivation after the second etching treatment (the degree of disappearance of the steep portion of the surface unevenness after the first etching step) is based on the material of the substrate for the mold, the means for the second etching treatment, and the The size and depth of the unevenness of the surface unevenness obtained by the first etching step are different from each other, and it is not possible to control the passivation state (the degree of shape passivation) to the maximum due to the etching amount in the second etching process. The amount of etching referred to here is also expressed by the thickness of the substrate reduced by the second etching treatment, similarly to the case of the first etching step. When the etching amount of the second etching treatment is small, the effect of passivating the shape of the surface unevenness obtained by the first etching step is insufficient. Therefore, whitening may occur sometimes with an anti-glare film manufactured by a mold having insufficient shape passivation. On the other hand, when the etching amount in the second etching treatment is too large, most of the unevenness of the surface unevenness formed by the first etching step disappears, and the mold has a substantially flat surface. An anti-glare film manufactured using a mold having such a substantially flat surface may have insufficient anti-glare properties. Here, the etching amount of the second etching treatment is preferably in the range of 1 to 50 μm, more preferably in the range of 6 to 21 μm, still more preferably in the range of 12 to 15 μm. Similarly to the first etching step, the second etching treatment can be performed by one etching treatment, or the etching treatment can be carried out by dividing the etching treatment into two or more times. When the etching process is divided into two or more times, the total amount of etching in the etching process of two or more times is preferably from 1 to 50 μm.

[9] 2nd plating step

In the second plating step, the substrate for a mold which has undergone the steps [6] and [7] above is preferably plated on the surface of the substrate for a mold which has undergone the steps [6] to [8]. Cover (preferably chrome plating described later). By performing the second plating step, the surface unevenness shape 47 of the substrate for a mold is passivated, and the surface of the mold can be protected by the plating. In the eighth aspect (d), the chrome plating layer 71 is formed on the second surface uneven shape 47 formed by the second etching treatment as described above, whereby the surface uneven shape becomes the shape passivation (the mold uneven surface 70). .

The plating layer formed by the second plating step is preferably chrome-plated from the viewpoints of gloss, high hardness, low friction coefficient, and good release property. Among the chrome plating, chrome plating, which is called gloss chrome plating or decorative chrome plating, which exhibits good gloss, is particularly preferable. The chrome plating is usually carried out by electrolysis, but the plating bath is used as a plating solution containing an aqueous solution of chromic anhydride (CrO ₃ ) and a small amount of sulfuric acid. The thickness of the chrome plating layer can be controlled by adjusting the current density and the electrolysis time.

By chrome plating, the surface irregularities of the surface of the substrate for the mold after the second etching treatment can be passivated, and a mold whose surface hardness is improved can be obtained. The degree to which the shape passivation at this time is controlled is the largest because of the thickness of the chrome plating layer. When the thickness is thin, the degree of shape passivation is insufficient, and the anti-glare film obtained by using such a mold sometimes causes whitening. On the other hand, when the thickness of the chrome plating layer is too thick, the antiglare property is insufficient. The present inventors have found that it is effective to produce a mold in such a manner that the thickness of the chrome plating layer is within a predetermined range in order to obtain an anti-glare film of an image display device capable of sufficiently preventing occurrence of whitening and having excellent anti-glare properties. That is, chrome plating The thickness of the layer is preferably in the range of 2 to 10 μm, more preferably in the range of 5 to 10 μm.

The chrome plating layer formed in the second plating step is preferably formed so that the Vickers hardness is 800 or more, and more preferably formed to be 1000 or more. When the Vickers hardness of the chrome plating layer is less than 800, the durability of the mold tends to be lowered when a mold is used to manufacture the antiglare film.

[10] 2nd grinding step

The final stage of the mold manufacturing is a second polishing step of polishing the surface (chromium plating layer) of the chrome-plated mold base material in the second plating step described above. The chrome plating has high gloss, high hardness, low friction coefficient and good release property. However, the high internal stress at the time of forming the chrome layer causes micro cracks on the surface. In the method for producing a mold used in the method for producing an anti-glare film of the present invention, it is preferable to eliminate the roughness of some micro-surface shapes caused by micro-cracks by chrome plating through the second polishing step. When an anti-glare film is produced using a mold having a rough surface shape due to chrome-plated micro-cracks, there is a fear that scattering on the surface becomes strong and whitening occurs. Further, when the occurrence density of the microcracks is distributed, the antiglare film produced by using the mold may have a position where the scattering is strong and a position where the scattering is weak, and unevenness occurs.

In the second polishing step, a suitable polishing method is preferably a method of selectively grinding the surface shape roughness caused by the micro cracks without affecting the mold uneven surface 70 formed in the second plating step. . If such a grinding method is specifically listed, polishing, fluid Grinding method, sand blasting method, and the like. The amount of polishing in which the amount of the chromium plating layer is reduced in the second polishing step is preferably 0.03 μm or more and 0.2 μm or less. When the amount of grinding is less than 0.03 μm, the effect of eliminating the roughness of the surface shape caused by the microcracks may not be sufficient. On the other hand, when the amount of polishing is higher than 0.2 μm, a flat region is generated on the uneven surface 70 of the mold. When an anti-glare film is produced using a mold which produces a flat region, there is a fear that the anti-glare property is insufficient.

Hereinafter, the above-described light embossing method which is preferable in the method for producing the antiglare film of the present invention will be described. As described above, the UV embossing method is particularly preferred as the photoembossing method, but the embossing method using an active energy ray-curable resin is specifically described herein.

In order to continuously manufacture the antiglare film of the present invention, when the antiglare film of the present invention is produced by photoembossing, it preferably comprises the following steps: [P1] coating step, which is a transparent support which is continuously conveyed On the object, a coating liquid containing an active energy ray-curable resin is applied to form a coating layer; and [P2] a curing step is applied to the surface of the coating layer, in a state of pressing the surface of the mold, from The transparent support side illuminates the activation energy line.

Further, when the antiglare film of the present invention is produced by the photoembossing method, it is more preferable to include: [P3] preliminary hardening step after the coating step [P1], before the hardening step [P2], in the coating layer The two end regions of the width direction illuminate the activation energy line.

Hereinafter, each of the drawings will be described in detail with reference to the drawings. step. Fig. 9 is a view schematically showing a preferred example of a manufacturing apparatus used in the method for producing an anti-glare film of the present invention. The arrow in Fig. 9 indicates the conveyance direction of the film or the rotation direction of the roller.

[P1] Coating step

In the coating step, a coating liquid containing an active energy ray-curable resin is applied onto a transparent support to form a coating layer. In the coating step, for example, as shown in FIG. 9, a coating liquid containing an active energy ray-curable resin composition is applied to the transparent support 81 drawn from the delivery roller 80 in the application region 83.

Regarding the coating of the coating liquid on the transparent support 81, for example, a gravure coating method, a micro gravure coating method, a bar coating method, a knife coating method, a pneumatic blade coating method, a contact coating method, The die coating method or the like is carried out.

(transparent support)

The transparent support 81 may be any one that transmits light, and for example, a glass or a plastic film can be used. The plastic film is only required to have appropriate transparency and mechanical strength. Specifically, any one of the transparent supporters used as the UV embossing method may be used, and further, in order to continuously manufacture the anti-glare film of the present invention by photo-embossing, it is preferable to have appropriate flexibility. Sex.

For the purpose of improving the applicability of the coating liquid and improving the bondability between the transparent support and the coating layer, various surface treatments can be applied to the surface (coating layer side surface) of the transparent support 81. Examples of the surface treatment include corona discharge treatment, glow discharge treatment, pickling treatment, alkali washing treatment, and ultraviolet irradiation treatment. Also, for example, a bottom may be formed on the transparent support 81. A coating liquid is applied to the other layers of the coating or the like and over the other layers.

Further, in the antiglare film of the present invention, in order to improve the bonding property between the transparent support and the polarizing film when manufacturing the polarizing film, it is preferable to face the transparent support (in contrast to the coating layer) The side surface) was previously hydrophilized by various surface treatments. This surface treatment can be carried out after the manufacture of the anti-glare film.

(coating liquid)

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

(1) Activated energy ray-curable resin

As the activated energy ray-curable resin, for example, a compound containing a polyfunctional (meth) acrylate compound can be preferably used. The polyfunctional (meth) acrylate compound refers to a compound having at least two (meth) acryloxy groups in the molecule. Specific examples of the polyfunctional (meth) acrylate compound include, for example, an ester compound of a polyhydric alcohol and a (meth) acrylate, a polyurethane (meth) acrylate compound, a polyester (meth) acrylate compound, A polyfunctional polymerizable compound containing two or more (meth)acrylonyl groups such as an epoxy (meth) acrylate compound.

Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, 1,2-propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, polypropylene glycol, propylene glycol, and butyl. Glycol, pentanediol, hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, 2,2'-thiodiethyl Alcohol, 1,4-cyclohexane dimethanol like dihydric alcohol; trimethylolpropane, glycerol, pentaerythritol, diglycerin, dipentaerythritol, bis(trimethylol)propane like 3 or more alcohols.

Specific examples of the ester of a polyhydric alcohol and (meth)acrylic acid include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, and 1,6-hexanediol. (Meth) acrylate, neopentyl glycol di(meth) acrylate, trimethylolpropane tri(meth) acrylate, trimethylolethane tri(meth) acrylate, tetramethylol Methane tri(meth) acrylate, 1,6-hexanediol di(meth) acrylate, tetramethylol methane tetra(meth) acrylate, pentaglycerol tri(meth) acrylate, pentaerythritol tri ( Methyl) acrylate, pentaerythritol tetra (meth) acrylate, glycerol tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol five ( Methyl) acrylate, dipentaerythritol hexa (meth) acrylate.

The polyurethane ester (meth) acrylate compound may, for example, be an urethanization reaction product of an organic isocyanate having a plurality of isocyanato groups in one molecule and a (meth)acrylic acid derivative having a hydroxyl group. Examples of the organic isocyanate having a plurality of isocyanato groups in one molecule include hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, naphthalene diisocyanate, diphenylmethane diisocyanate, xylene. An organic isocyanate having two isocyanato groups in one molecule such as xylylene diisocyanate or dicyclohexylmethane diisocyanate, and the organic cyanate ester is modified to be a cyanurate or an additive. An organic organic compound having 3 isocyanates in one molecule after biuret modification Isocyanate, etc. Examples of the (meth)acrylic acid derivative having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate. Ester, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 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 preferred hydroxyl group-containing polyester to be used is a polyester having a hydroxyl group obtained by a compound having a polyhydric alcohol and a carboxylic acid or a plurality of carboxyl groups and/or an esterification reaction thereof. The polyol may be listed in the same manner as the aforementioned compound. Further, examples of the phenols other than the polyhydric alcohols include bisphenol A and the like. 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 an anhydride thereof include maleic acid, phthalic acid, fumaric acid, methylene succinic acid, adipic acid, and terephthalic acid. Maleic anhydride, phthalic anhydride, trimellitic acid, cyclohexane dicarboxylic anhydride, and the like.

Among the polyfunctional (meth) acrylate compounds as described above, hexanediol di(meth) acrylate or pentylene is preferred from the viewpoint of improvement in strength of the cured product or ease of availability. Alcohol di(meth)acrylate, diethylene glycol (meth)acrylate, tripropylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylic acid An ester, an ester of dipentaerythritol hexa(meth) acrylate, or the like; an adduct of hexamethylene diisocyanate and 2-hydroxyethyl (meth) acrylate; isophorone diisocyanate and 2-hydroxy ethane Base (meth)acrylic acid An adduct of an ester; an adduct of toluene diisocyanate and 2-hydroxyethyl (meth) acrylate; an adduct modified with isophorone diisocyanate and 2-hydroxyethyl (meth) acrylate An adduct; and a biuret modified an adduct of isophorone diisocyanate and 2-hydroxyethyl (meth) acrylate. Further, 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 polyfunctional (meth) acrylate compound. Examples of the monofunctional (meth) acrylate compound include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and isobutyl (meth) acrylate. N-butyl methacrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, 2-hydroxyl (meth) acrylate Butyl ester, 2-hydroxy-3-phenoxypropyl (meth)acrylate, glycidyl (meth)acrylate, acryloylmorpholine, N-vinylpyrrolidone, (meth)acrylic acid Tetrahydrofurfuryl ester, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)acrylate, ethyl methacrylate, (meth)acrylic acid Benzyl methyl ester, 2-ethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethylcarbitol acrylate, (a) Phenyl oxyacrylate, ethylene oxide modified phenoxy (meth) acrylate, propylene oxide (meth) acrylate, nonyl phenol (meth) acrylate, ethylene oxide modification ( Methyl) acrylate, Propylene oxide modified nonylphenol (meth) acrylate, methoxy diethylene glycol (meth) acrylate, 2- (meth) Bing Xixi oxy-2-hydroxypropyl phthalate A (meth) acrylate such as an ester, dimethylaminoethyl (meth) acrylate or methoxy triethylene glycol (meth) acrylate. These compounds can be used individually or in combination of 2 or more types.

Further, the active energy ray-curable resin may contain a polymerizable oligomer. The hardness of the cured product can be adjusted by containing a polymerizable oligomer. The polymerizable oligomer may be, for example, the aforementioned polyfunctional (meth) acrylate compound, that is, an ester of a polyhydric alcohol with (meth)acrylic acid, a polyurethane (meth) acrylate compound, or a polyester (meth) acrylate. An oligomer such as a dimer or a trimer such as an ester compound or an epoxy (meth) acrylate.

The other polymerizable oligomer may, for example, be an amine obtained by a reaction of a polyisocyanate having at least two isocyanato groups in the molecule with a polyol having at least one (meth) acryloxy group. Formate (meth) acrylate oligomer. The polyisocyanate may, for example, be a polymer of hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate or xylene diisocyanate, and has at least one (meth) propylene oxyhydroxide. The polyhydric alcohol may be a (meth) acrylate having a hydroxyl group obtained by esterification reaction of a polyhydric alcohol with (meth)acrylic acid, and examples of the polyhydric alcohol include 1,3-butanediol. , 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, neopentyl glycol, polyethylene glycol, polypropylene glycol, trimethylolpropane, glycerol, Pentaerythritol, dipentaerythritol, and the like. The polyol having at least one (meth) propylene fluorenyloxy group is a part of an alcoholic hydroxyl group of a polyhydric alcohol esterified with (meth)acrylic acid, and the alcoholic hydroxyl group remains in the molecule.

In addition, as for the other examples of the polymerizable oligomer In other words, a compound having a plurality of carboxyl groups and/or a polyester (meth) propylene oligomer obtained by reacting an anhydride thereof with a polyol having at least one (meth) acryloxy group. The compound having a plurality of carboxyl groups and/or its anhydride may be the same as those described for the polyester (meth) acrylate of the above polyfunctional (meth) acrylate compound. Further, the polyol having at least one (meth) acryloxy group may be the same as those described for the urethane (meth) acrylate oligomer.

In addition to the above-mentioned polymerizable oligomer, examples of the urethane (meth) acrylate oligomer include a hydroxyl group-containing polyester, a hydroxyl group-containing polyether or a hydroxyl group-containing (meth) group. A compound obtained by reacting a hydroxyl group of an acrylate with an isocyanate. A polyester having a hydroxyl group which can be preferably used is a polyester having a hydroxyl group and a carboxylic acid or a plurality of carboxyl groups and/or a hydroxyl group-containing polyester obtained by esterification reaction thereof. The compound having a polyhydric alcohol or a plurality of carboxyl groups and/or an anhydride thereof may be the same as those described for the polyester (meth) acrylate compound of the polyfunctional (meth) acrylate compound. The hydroxyl group-containing polyether which can be preferably used is a hydroxyl group-containing polyether obtained by adding one or more kinds of alkylene oxide and/or ε-caprolactone to a polyol. The polyol may be the same as the user having the hydroxyl group-containing polyester. The hydroxyl group-containing (meth) acrylate which can be preferably used is the same as those described for the urethane (meth) acrylate oligomer of the polymerizable oligomer. The isocyanate is preferably a compound having one or more isocyanate groups in the molecule, and particularly preferably a two-membered isocyanate compound such as toluene diisocyanate or hexamethylene diisocyanate or isophorone diisocyanate.

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 activation energy ray used in the production of the antiglare film of the present invention. Further, when an electron beam is used as the activation energy ray, a coating liquid containing no photopolymerization initiator may be used for the production of the glare film of the present invention.

As the photopolymerization initiator, for example, an acetophenone-based photopolymerization initiator, a benzoin-based photopolymerization initiator, a diphenylketone photopolymerization initiator, an oxathioxanthone-based photopolymerization can be used. Starting agent, three Photopolymerization initiator, A bisazole photopolymerization initiator or the like. Further, as the photopolymerization initiator, for example, 2,4,6-trimethylbenzimidyldiphenylphosphine oxide, 2,2'-bis(o-chlorophenyl)-4,4',5 can also be used. , 5'-tetraphenyl-1,2'-diimidazole, 10-butyl-2-acridone, 2-ethyl hydrazine, diphenylethylenedione (benzil), 9,10-phenanthrenequinone (9,10-phenanthraquinone), camphorquinone, methyl phenylglyoxylate, titanocene compound, and the like. 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 is a solvent containing an organic solvent or the like in order to improve the coating property to the transparent support. The organic solvent may be an aliphatic hydrocarbon such as hexane, cyclohexane or octane; an aromatic hydrocarbon such as toluene or xylene; ethanol, 1-propanol, isopropanol, 1-butanol or cyclohexane. Alcohols such as alcohols; ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters of ethyl acetate, butyl acetate, isobutyl acetate, etc.; ethylene glycol monomethyl ether, ethylene glycol single a glycol ether such as diethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether or propylene glycol monoethyl ether; an esterified glycol ether such as ethylene glycol monomethyl ether acetate or propylene glycol monomethyl ether acetate; Cellosolve of methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, etc.; 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyl) A carbitol such as ethoxy)ethanol or 2-(2-butoxyethoxy)ethanol is used in consideration of viscosity and the like. These solvents may be used singly or in combination of several types as needed. The above organic solvent must be evaporated after coating. For this reason, the desired boiling point is in the range of 60 ° C to 160 ° C. Further, the saturated vapor pressure at 20 ° C is preferably in the range of 0.1 kPa to 20 kPa.

When the coating liquid contains a solvent, it is preferred to provide a drying step of evaporating the solvent and drying it after the coating step and before the first curing step. The drying system can be carried out by passing the transparent support 81 having the coating layer through the drying zone 84 as in the example shown in Fig. 9. The drying temperature is appropriately selected depending on the type of solvent or transparent support to be used. It is generally in the range of 20 ° C to 120 ° C, but is not limited by this. Further, when the number of drying furnaces is plural, the temperature can be changed for each drying furnace. The thickness of the dried coating layer is preferably from 1 to 30 μm.

In this manner, a laminate in which a transparent support and a coating layer are laminated is formed.

[P2] hardening step

In this step, the coating energy layer is irradiated from the side of the transparent support while the surface of the mold having the desired surface unevenness is pressed against the surface of the coating layer, thereby curing the coating layer. Transparent support The step of forming a hardened resin layer thereon. Thereby, the coating layer is hardened and the surface uneven shape of the uneven surface of the mold is transferred to the surface of the coating layer. The mold used here is a roll shape, and is manufactured by using a roll-shaped mold base material in the mold manufacturing method described above.

This step is carried out by, for example, Fig. 9, for example, for passing through the coating zone 83 (when the drying zone 84 is dried, and when there is a preliminary hardening step to be described later, it is further) The layered body having the coating layer by the preliminary hardening zone of the active energy ray irradiation device 86 is irradiated, and the activation energy ray is irradiated by the activation energy ray irradiation device 86 such as an ultraviolet ray irradiation device disposed on the side of the transparent support 81.

First, a roll-shaped mold 87 is pressed on the surface of the coating layer of the laminate subjected to the hardening step using a pinch roller 88 or the like, and the activated energy ray irradiation device 86 is used in this state, from the transparent support. The object 81 side is irradiated with an activation energy ray to cure the coating layer 82. Here, "curing the coating layer" means that the active energy ray-curable resin contained in the coating layer is subjected to a hardening reaction by the energy of the activation energy ray. The use of the nip roller can effectively prevent air bubbles from entering between the coating layer of the laminate and the mold. One or more of the active energy ray irradiation devices can be used.

After the activation energy ray is irradiated, the laminated body is peeled off from the mold 87 having the roll 89 on the outlet side as a fulcrum. The obtained transparent support and the cured coating layer in the cured coating layer are an antiglare layer to obtain the antiglare film of the present invention. The resulting anti-glare film is generally taken up by a film winding device 90. In this case, for the purpose of protecting the anti-glare layer, the surface of the anti-glare layer may be bonded to the surface of the anti-glare layer by sandwiching the adhesive layer having re-peelability. A protective film composed of ethylene glycol or polyethylene is taken up while being wound up. Further, although the case where the mold used is a roll shape has been described here, a mold other than the roll shape may be used. Further, after being peeled off from the mold, additional activation energy ray irradiation can be performed.

The type of the active energy ray-curable resin contained in the coating liquid can be appropriately selected from ultraviolet rays, electron beams, near ultraviolet rays, visible light, near infrared rays, infrared rays, X-rays, etc., for the activation energy rays used in the present step. Among these, ultraviolet rays and electron beams are preferable, and in view of simple treatment and high energy, ultraviolet rays are particularly preferable (as in the above, in the case of photoembossing, UV embossing is preferred).

As the light source of the ultraviolet light, for example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, an electrodeless lamp, a metal halide lamp, a xenon arc lamp, or the like can be used. Further, an ArF excimer laser, a KrF excimer laser, an excimer lamp, or a synchrotron radiation may be used. Among these, ultrahigh pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, electrodeless lamps, xenon arc lamps, and metal halide lamps can be preferably used.

Further, as for the electronic wire, there are a Cockcroft-Walton type, a Van de Graaff type, a resonance transformation type, and an insulation core transformation type. An electron beam of 50 to 1000 keV, preferably 100 to 300 keV, emitted by various electron beam particle accelerators of a linear type, a Dynamitron type, a high frequency type or the like.

When the activation energy ray is ultraviolet ray, the cumulative amount of light in the ultraviolet ray UVA is preferably 100 mJ/cm ² or more and 3000 mJ/cm ² or less, more preferably 200 mJ/cm ² or more and 2000 mJ/cm ² or less. Further, since the transparent support also absorbs ultraviolet rays on the short-wavelength side, the cumulative amount of ultraviolet light UVV (395 to 445 nm) including the visible light wavelength region may be preferably formed for the purpose of suppressing the absorption. Adjust the amount of exposure. The cumulative amount of light in the UVV is preferably 100 mJ/cm ² or more and 3000 mJ/cm ² or less, more preferably 200 mJ/cm ² or more and 2000 mJ/cm ² or less. When the cumulative amount of light is less than 100 mJ/cm ² , the hardening of the coating layer is insufficient, the hardness of the obtained antiglare layer becomes low, or the uncured resin adheres to the guide roller or the like, which becomes a cause of the contamination step. The tendency. Further, when the integrated light amount exceeds 3,000 mJ/cm ² , the heat radiated from the ultraviolet ray irradiation device may cause the transparent support to shrink and wrinkle.

[P3] preliminary hardening step

This step is a step of pre-hardening the two end regions by irradiating the activation energy rays at both end regions in the width direction of the transparent support of the coating layer before the hardening step. Fig. 10 is a cross-sectional view schematically showing a preliminary hardening step. In the tenth aspect, the end portion field 82b of the coating layer in the width direction (the direction orthogonal to the conveying direction) is a region including the end portion of the coating layer and within a predetermined width from the end portion.

In the preliminary hardening step, by hardening the top region in advance, the adhesion to the transparent support 81 is further improved in the end region, and in the step after the hardening step, a part of the hardened resin is peeled off to prevent The steps are contaminated. The end region 82b can be an area that is, for example, 5 mm or more and 50 mm or less from the end of the coating layer 82.

Refer to Figure 9 and Figure 10 for the end of the coating layer The irradiation active energy line system of the region is carried out by using a transparent support 81 having a coating layer 82 through, for example, a coating zone 83 (drying zone 84 when drying), respectively, for use in coating The activation energy ray irradiation device 85 such as an ultraviolet ray irradiation device in the vicinity of both end portions on the side of the cloth layer 82 illuminates the activation energy ray. The activation energy ray irradiation device 85 may be provided on the side of the transparent support 81 as long as it can illuminate the end region 82b of the coating layer 82 with the activation energy ray.

The type of the activation energy line and the light source are the same as the main hardening step. When the activation energy ray is ultraviolet ray, the cumulative amount of light in the UVA of the ultraviolet ray is preferably 10 mJ/cm ² or more and 400 mJ/cm ² or less, more preferably 50 mJ/cm ² or more and 400 mJ/cm ² or less. By irradiating so as to be 50 mJ/cm ² or more, deformation in the main hardening step can be effectively prevented. Further, when it exceeds 400 mJ/cm ² , the hardening reaction proceeds excessively, and as a result, the boundary band between the hardened portion and the uncured portion may be peeled off due to a difference in film thickness or internal stress.

[Use of Anti-glare Film of the Present Invention]

The anti-glare film of the present invention obtained in the above-described manner is used in an image display device or the like, and is usually used as a visual-side protective film of a visual-side polarizing plate and bonded to a polarizing film (that is, disposed on The surface of the image display device.). Further, when a polarizing film is used as the transparent support as described above, since the polarizing film-integrated anti-glare film can be obtained, the polarizing film-integrated anti-glare film can be used in an image display device. The image display device including the anti-glare film of the present invention has sufficient anti-glare properties at a wide viewing angle, and can simultaneously prevent whitening and glare from occurring at the same time.

(Example)

Hereinafter, the present invention will be described in more detail by way of examples. In the example, the “%” and “parts” of the content and the usage amount are based on the weight unless otherwise stated. The evaluation method of the mold or the anti-glare film in the following examples is as follows.

[1] Determination of surface shape of anti-glare film

(surface roughness parameter of surface uneven shape)

The surface roughness parameter of the anti-glare film was measured using a surface roughness measuring machine Surftest SJ-301 manufactured by Mitutoyo Co., Ltd. according to JIS B 0601. In order to prevent the sample from being bent, the optical transparent adhesive was attached to the glass substrate so that the uneven surface became a surface, and then measured.

(power spectrum of complex amplitude calculated from the elevation of the surface relief shape)

The elevation of the surface uneven shape of the anti-glare layer of the anti-glare film belonging to the sample to be tested was measured using a three-dimensional microscope PL μ 2300 (manufactured by Sensofar Co., Ltd.). In order to prevent the sample from being bent, the surface of the sample to be tested on the opposite side to the anti-glare layer is bonded to the glass substrate using an optically transparent adhesive, and then measured. In the measurement, the measurement was performed by setting the magnification of the objective lens to 10 times. The horizontal resolutions Δx and Δy were both 1.66 μm, and the measurement area was 1270 μm × 950 μm. A sample of 512 × 512 (measurement area: 850 μm × 850 μm) was sampled from the center of the obtained measurement data, and the elevation of the surface uneven shape (surface unevenness of the antiglare layer) of the antiglare film was taken as a two-dimensional function h ( x, y) and find. Secondly, the complex amplitude is calculated as a two-dimensional function ψ(x, y) according to the two-dimensional function h(x, y). The wavelength λ at the time of calculating the complex amplitude was set to 550 nm. The two-dimensional function Ψ(x, y) is obtained by discrete Fourier transform to obtain a two-dimensional function Ψ(f _x , f _y ). The two-dimensional function H(f _x , f _y ) of the two-dimensional power spectrum is calculated by squaring the absolute value of the two-dimensional function Ψ(f _x , f _y ), and the one-dimensional power belonging to the distance f from the origin is calculated. One of the spectrum functions H(f). For each sample, the elevation of the surface relief shape at five locations is determined, and the average of the one-dimensional function H(f) of the one-dimensional power spectrum calculated from the data is used as one dimension of the one-dimensional power spectrum of each sample. Function H(f).

[2] Determination of optical properties of anti-glare film

(haze)

The total haze of the anti-glare film is an optical transparent adhesive for the anti-glare film, and the surface of the sample to be tested opposite to the anti-glare layer is bonded to the glass substrate, and the anti-glare is applied to the glass substrate. The film was incident on the glass substrate side, and was measured by a haze meter "HM-150" manufactured by Murakami Color Research Laboratory Co., Ltd. according to the method of JIS K 7136. The surface haze is obtained by determining the internal haze of the anti-glare film, and the surface haze = total haze - internal haze is obtained by subtracting the internal haze from the total haze according to the following formula. The internal haze is determined by the anti-glare layer of the sample to be tested after the total haze is measured, and the cellulose triacetate film having a haze of approximately 0 is applied with glycerin and then measured in the same manner as the total haze.

(penetration sharpness)

The penetration sharpness of the anti-glare film was measured using a developmental measuring instrument "ICM-1DP" manufactured by Suga Tester Co., Ltd. according to the method of JIS K 7105. At this time, in order to prevent the sample from being bent, an optically transparent adhesive is used, and the surface of the sample to be tested on the opposite side to the antiglare layer is bonded to the glass substrate, and then measured. In this state, light was incident from the glass substrate side, and measurement was performed. The measured value here is a total value of values measured by using five types of optical combs having a width of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm, respectively, in the dark portion and the bright portion.

(Reflective reflectance measured at an incident angle of light of 45°)

The reflectance of the anti-glare film was measured using a developing device "ICM-1DP" manufactured by Suga Tester Co., Ltd. according to the method of JIS K 7105. At this time, in order to prevent the sample from being bent, an optically transparent adhesive is used, and the surface of the sample to be tested on the opposite side to the antiglare layer is bonded to the black acrylic substrate, and then measured. In this state, light was incident at 45° from the side of the anti-glare layer, and measurement was performed. The measured value here is a total value of the values measured by using four types of optical combs of 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm, respectively, in the dark portion and the bright portion.

(reflection sharpness measured by the incident angle of light 60°)

The reflectance of the anti-glare film was measured using a developing device "ICM-1DP" manufactured by Suga Tester Co., Ltd. according to the method of JIS K 7105. At this time, in order to prevent the sample from being bent, an optically transparent adhesive is used, and the surface of the sample to be tested on the opposite side to the antiglare layer is bonded to the black acrylic substrate, and then measured. In this state, light was incident at 60° from the side of the anti-glare layer, and measurement was performed. The measured value here is a total value of the values measured by using four types of optical combs of 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm, respectively, in the dark portion and the bright portion.

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

(reflective, white visual assessment)

In order to prevent reflection from the back surface of the anti-glare film, the surface of the sample to be tested on the opposite side to the anti-glare layer is attached to the black acrylic resin sheet, and from the side of the anti-glare layer in the bright room where the fluorescent lamp is lit The degree of reflection and the degree of whitening of the fluorescent lamp were visually evaluated by visual observation. Regarding the reflection system, the degree of reflection of the antiglare film when viewed from the front and the degree of reflection when viewed from the inclination of 30° were evaluated, respectively. The reflective and ubiquitous lines were evaluated in three stages of 1 to 3 according to the following criteria.

Reflective 1: No reflections were observed.

2: A slight reflection was observed.

3: Obvious reflection was observed.

Whitening 1: No whitening is observed.

2: A slight whitening was observed.

3: Whitening was clearly observed.

(evaluation of glare)

Glare is evaluated in the following order. That is, a reticle having a pattern of unit cells as shown in the plan view in Fig. 11 is first prepared. In the figure, the unit cell 100 is formed with a chrome-shielding pattern 101 having a hook width of 10 μm and having a hook width of 10 μm on the transparent substrate, and a portion where the chrome-shielding pattern 101 is not formed is the opening 102. Here, the size of the unit cell is 211 μm × 70 μm (length × width of the figure). Therefore, the size of the opening is 201 μm × 60 μm (length × width of the figure). The unit cell shown is formed by arranging a plurality of sides along the length and width to form a reticle.

Then, as shown in the schematic cross-sectional view of Fig. 12, The chrome-shielding pattern 111 of the mask 113 is placed on the light box 115 so as to be positioned above, and the anti-glare film 110 is attached to the glass sheet 117 by the adhesive so that the anti-glare layer becomes a surface. On the mask 113. A light source 116 is disposed in the light box 115. In this state, the degree of glare was evaluated as a function of seven steps by visual observation at a position 119 of about 30 cm from the sample. Level 1 is a state in which glare is not confirmed at all, level 7 is equivalent to a state in which glare is observed in a large amount, and level 4 is a state in which glare is observed slightly.

(comparative assessment)

The polarizing plate on both sides of the watch was peeled off from a commercially available liquid crystal television ["KDL-32EX550" manufactured by Sony Corporation). In place of the original polarizing plates, the polarizing plate "SUMIKARAN SRDB831E" manufactured by Sumitomo Chemical Co., Ltd. is bonded to the absorption axis of the original polarizing plate in the same manner on the back side and the display surface side. The adhesive is applied to the surface-side polarizing plate, and the anti-glare film shown in each of the following examples is bonded to the surface of the anti-glare film so that the uneven surface is a surface. In the same manner, the obtained liquid crystal television was started in a dark room, and the brightness of the black display state and the white display state was measured using a TOPCON (brightness meter) luminance meter "BM5A" type, and the contrast was calculated. The contrast here is expressed as the ratio of the brightness of the white display state with respect to the brightness of the black display state. As a result, the contrast measured in the state in which the antiglare film was attached was expressed as a ratio of the contrast measured in the state in which the antiglare film was not attached.

[4] Evaluation of patterns for the manufacture of anti-glare films

The created pattern data is set to a second-order binary image data, and the gradation is represented by a two-dimensional discrete function g(x, y). The horizontal resolutions Δx and Δy of the discrete function g(x, y) are both set to 2 μm. A two-dimensional function G(f _x , f _y ) is obtained by performing a discrete Fourier transform on the obtained two-dimensional function g( _x , _y ). The two-dimensional function G (f _x, f _y) and calculates the absolute value of the square two-dimensional power spectrum of the two-dimensional function _{Γ (f x, f y)} , and which belong to one of the functions of the distance from the origin of the f-dimensional power The one-dimensional function of the spectrum Γ(f).

<Example 1>

(Production of mold for manufacturing anti-glare film)

A ballard plating copper was prepared on the surface of an aluminum roll having a diameter of 300 mm (as A6063 of JIS). The Ballard copper plating system is composed of a copper plating layer/a thin silver plating layer/a surface copper plating layer, and the entire thickness of the plating layer is set to be about 200 μm. The copper-plated surface is mirror-polished, and a photosensitive resin is applied onto the polished copper-plated surface, followed by drying to form a photosensitive resin film. Next, the pattern of the pattern A shown in FIG. 13 is repeatedly placed on the photosensitive resin film and exposed to laser light for development. Exposure and development by laser light were carried out using Laser Stream FX (manufactured by Think Laboratory). For the photosensitive resin film, a positive photosensitive resin is used. Here, the pattern A is formed by a pattern having a random brightness distribution and is formed by a plurality of Gaussian function type band pass filters, the aperture ratio is 45%, and the spatial frequency of the one-dimensional power spectrum is 0.002 μm ^-1 . The ratio of Γ(0.002) to the frequency strength Γ(0.01) in the spatial frequency 0.01μm ^-1 Γ(0.01)/Γ(0.002) is 4.8, the intensity Γ(0.002) in the spatial frequency 0.002μm ^-1 and the spatial cycle number 0.02μm strength Γ (0.02) in a ratio of ^-1 Γ (0.02) / Γ (0.002 ) to 0.4, the spatial frequency intensity 0.002μm Γ (0.002) ^-1 0.04μm in the spatial frequency of the intensity Gamma] ^-1 ( The ratio 0.0(0.04)/Γ(0.002) of 0.04) is 5.5.

Thereafter, the first etching treatment is performed on the chlorinated second copper liquid. The amount of etching at this time was set so as to be 5 μm. The photosensitive resin film was removed from the roll after the first etching treatment, and the second etching treatment was performed again with the second copper chloride solution. The etching amount at this time was set so as to be 12 μm. After that, chrome processing is performed. In this case, the chrome plating thickness was set to 6 μm. The chrome-plated roller was subjected to buffing under the following conditions to prepare a mold A.

Abrasive material: Micro Plish (an acidified aluminum abrasive material with a particle size of 0.05 μm) (manufactured by Musashino Electronics Co., Ltd.)

Grinding cloth: cloth (red) (Musashino Electronics Co., Ltd.)

Roll rotation speed: 60 rpm

Push pressure: 1.1kPa

(production of anti-glare film)

The components described below were dissolved in ethyl acetate at a solid concentration of 60%, and after curing, an ultraviolet curable resin composition A having a film having a refractive index of 1.53 was formed.

This ultraviolet curable resin composition A was applied on a cellulose triacetate (TAC) film having a thickness of 60 μm so that the thickness of the dried coating layer was 5 μm, and it was set in a dryer set at 60° C. Dry for 3 minutes. The dried film was adhered to the molding surface (surface having the surface uneven shape) of the previously obtained mold A so that the dried coating layer was placed on the mold side, and was adhered by a rubber roller. In this state, the light of the high-pressure mercury lamp having a strength of 20 mW/cm ² was irradiated so as to be h-line converted light amount to be 200 mJ/cm ² from the side of the TAC film, and the coating layer was cured. Anti-glare film. Thereafter, the obtained 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 mold B was produced in the same manner as the mold A of the first embodiment except that the pattern obtained by repeating the pattern B shown in Fig. 14 was exposed on the photosensitive resin film by laser light. An anti-glare film was produced in the same manner as in Example 1 except that the mold A was replaced with the mold B. This anti-glare film is used as the anti-glare film B. Here, the pattern B is formed by a pattern having a random brightness distribution and is formed by a plurality of Gaussian function type band pass filters, the aperture ratio is 40%, and the spatial frequency of the one-dimensional power spectrum is 0.002 μm ^-1 . The ratio Γ(0.01)/Γ(0.002) of Γ(0.002) to the intensity Γ(0.01) in the spatial frequency 0.01μm ^-1 is 3.7, the intensity Γ(0.002) in the spatial frequency 0.002μm ^-1 and the spatial frequency 0.02μm strength Γ (0.02) in a ratio of ^-1 Γ (0.02) / Γ (0.002 ) to 0.3, the spatial frequency intensity in Gamma] 0.002μm ^-1 (0.002) and the spatial frequency intensity in the Gamma] 0.04μm ^-1 (0.04) The ratio (0.04) / Γ (0.002) is 4.6.

<Example 3>

The mold C was produced in the same manner as the mold A of the first embodiment except that the pattern obtained by repeating the pattern C shown in Fig. 15 was exposed on the photosensitive resin film by laser light. An anti-glare film was produced in the same manner as in Example 1 except that the mold A was replaced with the mold C. This anti-glare film is used as the anti-glare film C. Here, the pattern C is formed by a pattern having a random brightness distribution and is formed by a plurality of Gaussian function type band pass filters, the aperture ratio is 45%, and the spatial frequency of the one-dimensional power spectrum is 0.002 μm ^-1 . The ratio Γ(0.01)/Γ(0.002) of Γ(0.002) to the intensity Γ(0.01) in the spatial frequency 0.01μm ^-1 is 3.5, the intensity Γ(0.002) in the spatial frequency 0.002μm ^-1 and the spatial frequency 0.02μm strength Γ (0.02) in a ratio of ^-1 Γ (0.02) / Γ (0.002 ) 0.42 Gamma] in the spatial frequency intensity 0.002μm ^-1 (0.002) and the spatial frequency intensity in the Gamma] 0.04μm ^-1 (0.04) The ratio 0.0(0.04)/Γ(0.002) is 5.5.

<Comparative Example 1>

The mold D was produced in the same manner as the mold A of the first embodiment except that the pattern obtained by repeating the pattern D shown in FIG. 16 was exposed on the photosensitive resin film by laser light. An anti-glare film was produced in the same manner as in Example 1 except that the mold A was replaced with the mold D. This anti-glare film is used as the anti-glare film D. Here, the pattern D is formed by a pattern having a random brightness distribution and is formed by a plurality of Gaussian function type band pass filters, the aperture ratio is 35%, and the spatial frequency of the one-dimensional power spectrum is 0.002 μm ^-1 . The ratio Γ(0.01)/Γ(0.002) of Γ(0.002) to the intensity Γ(0.01) in the spatial frequency 0.01μm ^-1 is 4.8, the intensity Γ(0.002) in the spatial frequency 0.002μm ^-1 and the spatial frequency 0.02μm strength Γ (0.02) in a ratio of ^-1 Γ (0.02) / Γ (0.002 ) to 0.5, the spatial frequency intensity in Gamma] 0.002μm ^-1 (0.002) and the spatial frequency intensity in the Gamma] 0.04μm ^-1 (0.04) The ratio (0.04) / Γ (0.002) is 6.9.

<Comparative Example 2>

In addition to the use of an aluminum roll having a diameter of 200 mm (A6063 of JIS), the pattern obtained by repeating the pattern E shown in FIG. 17 was exposed on the photosensitive resin film by laser light, and was produced in the same manner as in Production Example 1. The mold E was produced in the same manner as in the mold A, and an anti-glare film was produced in the same manner as in Example 1 except that the mold A was replaced with the mold E. This anti-glare film was used as the anti-glare film E. Here, the pattern E is formed by a pattern having a random brightness distribution and is formed by a plurality of Gaussian function type band pass filters, the aperture ratio is 45.0%, and the spatial frequency of the one-dimensional power spectrum is 0.002 μm ^-1 . The ratio Γ(0.01)/Γ(0.002) of Γ(0.002) to the intensity Γ(0.01) in the spatial frequency 0.01μm ^-1 is 4.2, the intensity Γ(0.002) in the spatial frequency 0.002μm ^-1 and the spatial frequency 0.02μm strength Γ (0.02) in a ratio of ^-1 Γ (0.02) / Γ (0.002 ) is 14, the spatial frequency intensity in Gamma] 0.002μm ^-1 (0.002) and the spatial frequency intensity in the Gamma] 0.04μm ^-1 (0.04) The ratio 0.0(0.04)/Γ(0.002) is 208.

<Comparative Example 3>

The surface of a 300 mm diameter aluminum roll (JIS A5056) was mirror-polished, and for the ground aluminum surface, a blasting device (manufactured by Fujia Co., Ltd.) was used to make zirconia beads TZ-SX-17 (TOSOH ( (manufacturing system, average particle diameter: 20 μm) was carried out at a blasting pressure of 0.1 MPa (gauge pressure, the same applies hereinafter), and a bead usage amount of 8 g/cm ² (the amount of use of each surface area of the roll of 1 cm ^{2 was} the same as the following). Sandblasting applies irregularities on the surface of the aluminum roll. The obtained embossed aluminum roll was subjected to electroless nickel plating to prepare a mold F. At this time, the thickness of the electroless nickel plating was set to 15 μm. An anti-glare film was produced in the same manner as in Example 1 except that the mold A was replaced with the mold F. This anti-glare film is used as the anti-glare film F.

<Comparative Example 4>

A bladed copper plate was prepared on the surface of an aluminum roll (with JIS A5056) having a diameter of 200 mm. The Ballard copper plating system is composed of a copper plating layer/a thin silver plating layer/a surface copper plating layer, and the overall thickness of the plating layer is about 200 μm. The copper-plated surface is mirror-polished, and the zirconia beads "TZ-SX-17" (TOSOH (manufactured by the company), average particle size) are used on the polished surface. : 20 μm) Sand blasting was performed at a blasting pressure of 0.05 MPa (gauge pressure, the same applies hereinafter), and the bead usage amount was 6 g/cm ² , and irregularities were applied to the surface of the aluminum roller. A mold G was produced by performing chrome-plating processing on the obtained copper-plated aluminum roll with irregularities. At this time, the chrome plating thickness was set to 6 μm. An anti-glare film was produced in the same manner as in Example 1 except that the mold A was replaced with the mold G. This anti-glare film is used as the anti-glare film G.

[evaluation result]

The evaluation results of the antiglare films obtained in the above Examples and Comparative Examples are shown in Table 1.

The anti-glare films A to C (Examples 1 to 3) satisfying the requirements of the present invention, although low in haze, have excellent anti-glare properties regardless of the viewing angle on the front side or the inclined surface, and are white and glare The suppression effect is also sufficient. On the other hand, the anti-glare film D (Comparative Example 1) was whitened. The antiglare film E (Comparative Example 2) was insufficient in antiglare property when viewed from a tilting surface. The anti-glare film F (Comparative Example 3) is prone to glare. The antiglare film G (Comparative Example 4) was insufficient in antiglare property when viewed from the oblique angle.

(industrial availability)

The anti-glare film of the present invention is advantageously used for an image display device such as a liquid crystal display.

1‧‧‧Anti-glare film

2‧‧‧Subtle bumps

5‧‧‧Main normal direction

101‧‧‧ Transparent support

102‧‧‧Anti-glare layer

103‧‧‧ Lowest elevation surface

Claims (2)

An anti-glare film comprising a transparent support and an anti-glare layer having a fine surface uneven shape formed on the transparent support, wherein the anti-glare film is characterized in that the total haze is 0.1% or more and 3% or less The surface haze is 0.1% or more and 2% or less, and the kurtosis Rku of the roughness curve of the surface unevenness is 4.9 or less, and the power spectrum of the complex amplitude obtained by the following power spectrum calculation method satisfies the following (1) ) to (3) all conditions of: (1) the spatial frequency power spectrum intensity 0.002μm H (0.002) ^-1 and in the spatial frequency power spectrum intensity H ^-1 in the 0.01μm (0.01) ratio H (0.01 ) / H (0.002) is 0.02 to 0.6; (2) the spatial frequency power spectrum of 0.002μm intensity ^-1 H (0.002) and the spatial frequency power spectrum of 0.02μm intensity ^-1 H (0.02) of ^-1 strength of 0.04μm and the spatial frequency power spectrum, and (3) the spatial frequency power spectrum intensity H 0.002μm (0.002) of ^-1; ratio H (0.02) / H (0.002 ) 0.005 or more and 0.05 or less H (0.04) ratio H (0.04) / H (0.002) is 0.0005 or more and 0.01 or less; wherein <power spectrum calculation method> (A) is defined by the average of the elevation of the surface unevenness shape (B) defining a minimum elevation surface and a highest elevation surface, the lowest elevation surface comprising a point at which the elevation of the surface relief shape is the lowest and parallel to the virtual plane of the average surface, the highest elevation surface a plane including the highest elevation of the surface relief shape and parallel to the virtual plane of the average plane; (C) a wavelength of 550 nm incident from a principal normal direction perpendicular to the lowest elevation surface and emitted from the highest elevation surface The plane wave is obtained by calculating a power spectrum of the complex amplitude when the complex amplitude of the highest elevation surface is calculated based on the elevation of the surface uneven shape and the refractive index of the antiglare layer. The anti-glare film according to the first aspect of the patent application is a penetrating sharpness measured by using five types of optical combs having a width of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm in the dark portion and the bright portion. The total Tc is 375% or more, and the total of the reflection sharpness measured at the incident angle of light of 45° is 4 types of optical combs having a dark portion and a bright portion of 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm. (45) is 180% or less, and the total of the reflection sharpness measured by the optical comb of four types of 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm of the dark portion and the bright portion at an incident angle of light of 60° is used. (60) is 240% or less.