Optical film, and polarizer, surface plate, image display panel and image display device using optical film, and manufacturing method of optical film, and selection method of optical film, and evaluation method of fingerprint wiping property

Abstract

To provide an optical film having an excellent antiglare property and fingerprint wiping property.SOLUTION: An optical film including a first surface and a second surface which is opposite to the first surface, includes: an antireflection layer and an antiglare layer in this order from the first surface to the second surface, where the first surface has an uneven shape. A dale void volume, Vvv, defined by ISO 25178-2: 2012 of the first surface is 0.005 ml / m2 or more, and a drop contact angle measured by the following method is 30.0 degrees or more. [Measurement of Drop Contact Angle] A droplet with surface tension of 30 mN / m is dropped from the height of 45 mm onto the first surface of the optical film. The droplet is dropped from a direction perpendicular to the first surface. A static contact angle 10 seconds after the droplet landing thereon is measured by the θ / 2 method.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an optical film, a polarizing plate, a front plate, an image display panel, and an image display device using the optical film, a method for producing the optical film, a method for selecting an optical film, and a method for evaluating fingerprint wiping removability. [Background technology]

[0002] Optical films are often installed on the surfaces of image display devices, such as televisions, notebook PCs, and desktop PC monitors, to suppress reflections from the surface and to prevent background objects, such as lighting and people, from being caught in the images. As optical films, for example, Patent Documents 1 to 3 have been proposed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 026466 [Patent Document 2] International Publication No. 2019 / 026471 [Patent Document 3] JP 2019-85473 A Summary of the Invention [Problem to be solved by the invention]

[0004] The optical films of Patent Documents 1 and 2 are antiglare films having an antiglare layer with unevenness formed on the surface. Optical films having an uneven surface tend to have poor fingerprint wiping properties because fingerprints get into the uneven surface. The better the antiglare properties of an antiglare film, the more likely it is that the fingerprint wiping properties will be poor. The optical films of Patent Documents 1 and 2 do not consider antifouling properties at all.

[0005] The optical film of Patent Document 3 is a coated film in which the sliding angle of oleic acid is 32° or less. The coated film of Patent Document 3 aims to make it easier to wipe off fingerprints, but the fingerprint wiping property is not good. If fingerprints on an optical film are not wiped off sufficiently, the appearance of the optical film is deteriorated due to the contrast in optical properties between a portion having fingerprint components and a portion not having fingerprint components. In particular, in the case of an optical film having an anti-reflection layer, the contrast in reflectance between a portion having fingerprint components and a portion not having fingerprint components becomes large, and the appearance of the optical film is greatly deteriorated.

[0006] An object of the present disclosure is to provide an optical film having an uneven surface and an antireflection layer on the surface, the optical film having excellent antiglare properties and good fingerprint wiping properties.An object of the present disclosure is to provide a polarizing plate, a front plate, an image display panel, and an image display device having excellent antiglare properties and good fingerprint wiping properties.An object of the present disclosure is to provide a manufacturing method for an optical film having excellent antiglare properties and good fingerprint wiping properties.An object of the present disclosure is to provide a method for selecting an optical film having excellent antiglare properties and good fingerprint wiping properties.An object of the present disclosure is to provide an evaluation method capable of easily evaluating fingerprint wiping properties. [Means for solving the problem]

[0007] The present disclosure provides the following [1] to [8]. [1] An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, The first surface has an uneven shape, The first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2 That's all. An optical film having a drop contact angle of 30.0 degrees or more as measured by the following method. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped from a height of 45 mm onto the first surface of the optical film. The droplet is dropped perpendicularly to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method. [2] A polarizing plate having a polarizer, a first transparent protective plate arranged on one side of the polarizer, and a second transparent protective plate arranged on the other side of the polarizer, A polarizing plate, wherein at least one of the first transparent protective plate and the second transparent protective plate is the optical film described in [1], and the second surface of the optical film is arranged opposite the polarizer. [3] A front panel for an image display device, comprising a protective film laminated onto a resin plate or a glass plate, the protective film being the optical film described in [1], and the second surface of the optical film being arranged opposite the resin plate or the glass plate. [4] An image display panel having a display element and an optical film arranged on a light exit surface side of the display element, the optical film including the optical film according to [1]. [5] An image display device comprising the image display panel according to [4]. [6] A method for producing the optical film according to [1], A method for producing an optical film, comprising a first step of forming an antiglare layer on a substrate, and a second step of forming an antireflection layer on the antiglare layer. [7] A method for selecting an optical film that satisfies the following selection conditions: (Optical film selection criteria) An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, The first surface has an uneven shape, The first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2That's all. The drop contact angle measured by the method described below is 30.0 degrees or more. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped from a height of 45 mm onto the first surface of the optical film. The droplet is dropped perpendicularly to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method. [8] A method for evaluating fingerprint wiping removability, using the drop contact angle measured by the following method as the evaluation index. <Drop contact angle measurement> A droplet with a surface tension of 30 mN / m is dropped from a height of 45 mm onto the surface of the measurement object. The droplet is dropped perpendicular to the surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method. Effect of the Invention

[0008] The optical film, polarizing plate, front plate, image display panel, and image display device of the present disclosure can provide excellent anti-glare properties and good fingerprint wiping properties. The manufacturing method of the optical film of the present disclosure can easily manufacture an optical film that has excellent anti-glare properties and good fingerprint wiping properties. The selection method of the optical film of the present disclosure can efficiently select an optical film that has excellent anti-glare properties and good fingerprint wiping properties. The evaluation method of the fingerprint wiping properties of the present disclosure can easily evaluate the fingerprint wiping properties of a measurement object. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic cross-sectional view showing one embodiment of an optical film of the present disclosure. [Diagram 2] 1 is a cross-sectional view illustrating an embodiment of an image display panel of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present disclosure will be described. [Optical film] The optical films of the present disclosure are as follows: An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, The first surface has an uneven shape, The first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2 That's all. An optical film having a drop contact angle of 30.0 degrees or more as measured by the following method. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped from a height of 45 mm onto the first surface of the optical film. The droplet is dropped perpendicularly to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method.

[0011] FIG. 1 is a schematic cross-sectional view of the cross-sectional shape of an optical film 100 of the present disclosure. The optical film 100 in Fig. 1 has a first surface having an uneven shape and a second surface that is the surface opposite to the first surface. In Fig. 1, the upper surface is the first surface and the lower surface is the second surface. The optical film in FIG. 1 has, from the first surface to the second surface, an antireflection layer 30, an antiglare layer 20, and a substrate 10 in this order. Fig. 1 is a schematic cross-sectional view. That is, the scale of each layer constituting the optical film 100 and the scale of the concave-convex shape are schematic for ease of illustration and differ from the actual scale. The same applies to Figs. 2 and 3.

[0012] The optical film of the present disclosure is not limited to the laminated structure of Fig. 1. For example, the optical film of the present disclosure may have a laminated structure without a substrate. The optical film of the present disclosure may have layers other than the substrate, the antiglare layer, and the antireflection layer.

[0013] <Side 1> The optical film of the present disclosure has a first surface. In the optical film of the present disclosure, the first surface is preferably a surface of the antireflection layer.

[0014] The first surface of the optical film has an uneven shape, and the protruding valley volume Vvv defined in ISO 25178-2:2012 is 0.005 ml / m 2 If the first surface does not have an uneven surface, the antiglare properties of the optical film cannot be improved. Even if the first surface has an uneven surface, the antiglare properties of the optical film cannot be improved. 2 If it is less than this, the antiglare property of the optical film cannot be improved.

[0015] Vvv is 0.007ml / m 2 It is preferable that the concentration is 0.010 ml / m or more. 2 More preferably, it is 0.020 ml / m or more. 2 More preferably, it is 0.030 ml / m or more. 2 More preferably, it is equal to or greater than this. If Vvv is too large, it tends to be difficult to achieve a drop contact angle of 30.0 degrees or more. For this reason, Vvv is set to 0.100 ml / m 2 Preferably, it is 0.080 ml / m or less. 2 More preferably, it is 0.060 ml / m or less. 2 More preferably, it is 0.045 ml / m or less. 2 It is more preferable that:

[0016] An embodiment of the range of Vvv of the first surface is 0.005 ml / m 2 More than 0.100ml / m 2 Below, 0.005ml / m 2 More than 0.080ml / m 2 Below, 0.005ml / m 2 More than 0.060ml / m 2 Below, 0.005ml / m 2 More than 0.045ml / m 2 Below, 0.007ml / m 2 More than 0.100ml / m 2 Below, 0.007ml / m2 More than 0.080ml / m 2 Below, 0.007ml / m 2 More than 0.060ml / m 2 Below, 0.007ml / m 2 More than 0.045ml / m 2 Below, 0.010ml / m 2 More than 0.100ml / m 2 Below, 0.010ml / m 2 More than 0.080ml / m 2 Below, 0.010ml / m 2 More than 0.060ml / m 2 Below, 0.010ml / m 2 More than 0.045ml / m 2 Below, 0.020ml / m 2 More than 0.100ml / m 2 Below, 0.020ml / m 2 More than 0.080ml / m 2 Below, 0.020ml / m 2 More than 0.060ml / m 2 Below, 0.020ml / m 2 More than 0.045ml / m 2 Below, 0.030ml / m 2 More than 0.100ml / m 2 Below, 0.030ml / m 2 More than 0.080ml / m 2 Below, 0.030ml / m 2 More than 0.060ml / m 2 Below, 0.030ml / m 2 More than 0.045ml / m 2 The following are included:

[0017] The first surface of the optical film has a drop contact angle of 30.0 degrees or more, as measured by the following method. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped from a height of 45 mm onto the first surface of the optical film. The droplet is dropped perpendicularly to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method.

[0018] If the drop contact angle of the first surface is less than 30.0 degrees, the fingerprint wiping-off property cannot be improved. The relationship between the drop contact angle and the fingerprint wiping-off property will be explained below. In the drop contact angle measurement of the present disclosure, a droplet is dropped from a height of 45 mm onto the first surface of the optical film. The droplet that has fallen onto the first surface is crushed by the impact of the drop, so the contact angle of the droplet immediately after the drop tends to be small. In particular, in the case of an optical film having an uneven shape with Vvv equal to or greater than a predetermined value, the droplet is likely to wet and spread, so the contact angle of the droplet immediately after the drop tends to be small. Liquid present in a crushed shape on the first surface of the optical film is difficult to wipe off. In the measurement of the drop contact angle of the present disclosure, the static contact angle 10 seconds after the droplet lands is measured using the θ / 2 method. The optical film of the present disclosure has a drop contact angle of 30.0 degrees or more. In other words, the optical film of the present disclosure having a drop contact angle of 30.0 degrees or more means that droplets crushed by the impact of being dropped will recover to a shape close to a sphere. For this reason, the optical film of the present disclosure has a Vvv of 0.005 ml / m 2 Despite having the above-described uneven shape, the fingerprint can be easily wiped off.

[0019] When the surface of the optical film is touched with a finger, the pressure of the touch causes fingerprint components to penetrate into the uneven surface. In the drop contact angle measurement of the present disclosure, the droplet is dropped from a height of 45 mm because of the above-mentioned phenomenon (the phenomenon in which fingerprint components penetrate into the uneven surface due to pressure) being taken into consideration. In the drop contact angle measurement, the amount of the droplet dropped is preferably 5.0 μl.

[0020] Fingerprints contain not only water but also sebum and the like. For this reason, in the measurement of the drop contact angle in the present disclosure, a liquid with a surface tension of 30 mN / m is used instead of pure water. In this specification, a liquid with the following composition is used as the liquid with a surface tension of 30 mN / m. In this specification, the surface tension refers to a value measured using a Wilhelmy surface tensiometer specified in JIS K2241:2017. <Composition of a liquid with a surface tension of 30mN / m> A liquid containing 100% ethylene glycol monoethyl ether by mass.

[0021] The drop contact angle is preferably 40.0 degrees or more, more preferably 45.0 degrees or more, and even more preferably 50.0 degrees or more. If the drop contact angle is too large, the content of the fluorine-based compound and the silicone-based compound in the anti-reflection layer increases, and the scratch resistance of the optical film is likely to decrease. Therefore, the drop contact angle is preferably 70.0 degrees or less, more preferably 60.0 degrees or less, and even more preferably 55.0 degrees or less.

[0022] Examples of the range of the drop contact angle of the first surface include 30.0 degrees or more and 70.0 degrees or less, 30.0 degrees or more and 60.0 degrees or less, 30.0 degrees or more and 55.0 degrees or less, 40.0 degrees or more and 70.0 degrees or less, 40.0 degrees or more and 60.0 degrees or less, 40.0 degrees or more and 55.0 degrees or less, 45.0 degrees or more and 70.0 degrees or less, 45.0 degrees or more and 60.0 degrees or less, 45.0 degrees or more and 55.0 degrees or less, 50.0 degrees or more and 70.0 degrees or less, 50.0 degrees or more and 60.0 degrees or less, and 50.0 degrees or more and 55.0 degrees or less.

[0023] In this specification, Vvv, Vvc and Vmp are calculated assuming that the areal load ratio separating the core portion and the protruding peaks is 10% and that separating the core portion and the protruding valleys is 80%. In this specification, Sxp means the difference between the height at an areal bearing ratio of 2.5% and the height at an areal bearing ratio of 50%.

[0024] In this specification, the surface shapes of Vvv, Vvc, Vmp, Sxp, Sal, etc. are preferably measured using a confocal laser microscope. Examples of confocal laser microscopes include the "VK-X" series from Keyence Corporation. In addition, by using the "multi-file analysis application" of the above-mentioned "VK-X" series, Vvv, Vvc, Vmp, Sxp, and Sal can be easily calculated. The measurement conditions for measuring Vvv, Vvc, Vmp, Sxp, and Sal using the aforementioned "VK-X" series are preferably in accordance with the conditions described in the Examples. For example, the F-operation is preferably plane tilt correction (area designation). The measurement area is preferably a rectangle with one side of 50 μm to 200 μm, and the number of measurement points per side is preferably 500 to 2000.

[0025] In this specification, the surface shape (Vvv, Vvc, Vmp, Sxp, and Sal), contact angle (drop contact angle, pure water contact angle), element ratio (F / inorganic Si, organic Si / inorganic Si, F / organic Si, etc.), optical properties (R SCI Unless otherwise specified, each of the following properties (e.g., haze, total light transmittance, transmitted image clarity, etc.) means the average value of 14 measured values ​​obtained by excluding the maximum and minimum values ​​from the measured values ​​at 16 locations. In this specification, the 16 measurement points are preferably centered on 16 intersections of lines drawn by excluding a 1 cm area from the outer edge of the measurement sample as a margin and dividing the remaining area into 5 equal parts vertically and horizontally. For example, when the measurement sample is rectangular, a 0.5 cm area from the outer edge of the rectangle is excluded as a margin, and the measurement is performed with 16 intersections of dotted lines dividing the remaining area into 5 equal parts vertically and horizontally as the center. Then, the average value of 14 measurement values ​​excluding the maximum and minimum values ​​from the 16 measurement points is preferably set as the parameter value. When the measurement sample is a shape other than a rectangle, such as a circle, an ellipse, a triangle, or a pentagon, it is preferable to draw a rectangle inscribed in these shapes and perform 16 measurements on the rectangle using the above method.

[0026] In this specification, the surface shape (Vvv, Vvc, Vmp, Sxp, and Sal), contact angle (drop contact angle, pure water contact angle), surface tension, element ratio (F / inorganic Si, organic Si / inorganic Si, F / organic Si, etc.), optical properties (R SCI Unless otherwise specified, the following characteristics (e.g., haze, total light transmittance, transmitted image clarity, etc.) are measured at a temperature of 23±5°C and a relative humidity of 40% to 65%. In addition, before starting each measurement, the target sample is exposed to the above atmosphere for 30 minutes to 60 minutes before the measurement. In the optical film of the present disclosure, the pure water contact angle of the first surface is preferably 100 degrees or more and 120 degrees or less, and more preferably 110 degrees or more and 115 degrees or less. The pure water contact angle can be measured by dropping 1.0 μL of pure water onto the surface on the first side, and measuring the static contact angle 10 seconds after the drop has landed according to the θ / 2 method.

[0027] The first surface of the optical film of the present disclosure preferably has a ratio (Vvv / Vvc) of Vvv to Vvc, which is the core space volume defined in ISO 25178-2:2012, of 0.10 or less. By setting Vvv / Vvc to 0.10 or less, it is possible to more easily improve the ease of wiping off fingerprints. Vvv / Vvc is more preferably 0.09 or less, and even more preferably 0.08 or less.

[0028] The first surface of the optical film of the present disclosure has a peak volume Vmp of 0.005 ml / m as defined in ISO 25178-2:2012. 2 More than 0.100ml / m 2 It is preferable that: Vmp of the first surface is 0.005ml / m 2 By setting the value to 0.007 ml / m or more, it is possible to easily obtain good antiglare properties. 2 More preferably, it is 0.010 ml / m or more. 2 More preferably, it is 0.020 ml / m or more. 2 More preferably, it is equal to or greater than this. Vmp of the first surface is 0.100ml / m 2 By setting the Vmp to 0.080 (ml / m or less), the scratch resistance of the optical film can be easily improved. 2 ) or less, and more preferably 0.060 (ml / m 2 ) or less, and more preferably 0.045 (ml / m 2 ) or less is more preferable.

[0029] The first surface of the optical film of the present disclosure preferably has a minimum autocorrelation length Sal defined in ISO 25178-2:2012 of 4.0 μm or more and 12.0 μm or less.

[0030] Sal is a parameter that focuses on the horizontal direction. The smaller Sal is, the more densely the concaves and convexes of the first surface are, and the larger Sal is, the more widely the intervals between the concaves and convexes of the first surface are. The value of the "average length of roughness curve element RSm" specified in JIS B0601 is hardly affected by minute concaves and convexes, but only by large concaves and convexes. On the other hand, the value of Sal is affected not only by large concaves and convexes, but also by minute concaves and convexes, which differs from RSm. Also, even if the intervals between the concaves and convexes are wide, if the convex parts are small or the concaves and convexes have a complex shape, Sal tends to be small. Also, if the convex parts have a monotonous shape, Sal tends to be large.

[0031] By setting Sal to 4.0 μm or more, it is possible to more easily improve the ease of wiping off fingerprints.By setting Sal to 12.0 μm or less, it is possible to more easily improve the antiglare properties. The lower limit of Sal is more preferably 5.0 μm or more, and even more preferably 6.0 μm or more.The upper limit of Sal is more preferably 11.0 μm or less, and even more preferably 10.0 μm or less. Examples of the range of Sal of the first surface include 4.0 μm or more and 12.0 μm or less, 4.0 μm or more and 11.0 μm or less, 4.0 μm or more and 10.0 μm or less, 5.0 μm or more and 12.0 μm or less, 5.0 μm or more and 11.0 μm or less, 5.0 μm or more and 10.0 μm or less, 6.0 μm or more and 12.0 μm or less, 6.0 μm or more and 11.0 μm or less, and 6.0 μm or more and 10.0 μm or less.

[0032] The first surface of the optical film of the present disclosure preferably has a pole height Sxp defined in ISO 25178-2:2012 of 0.15 μm or more and 2.00 μm or less. Sxp is a parameter that indicates the difference between the average surface of the uneven shape and the convex parts after removing particularly high convex parts from the uneven shape. By making Sxp 0.15 μm or more, it is easier to improve the anti-glare properties. By making Sxp 2.00 μm or less, it is easier to improve the fingerprint wiping properties. The lower limit of Sxp is more preferably 0.20 μm or more, more preferably 0.25 μm or more, more preferably 0.50 μm or more, and more preferably 0.70 μm or more. The upper limit of Sxp is more preferably 1.80 μm or less, more preferably 1.50 μm or less, and more preferably 1.40 μm or less. The range of Sxp of the first surface is, for example, 0.15 μm or more and 2.00 μm or less, 0.15 μm or more and 1.80 μm or less, 0.15 μm or more and 1.50 μm or less, 0.15 μm or more and 1.40 μm or less, 0.20 μm or more and 2.00 μm or less, 0.20 μm or more and 1.80 μm or less, 0.20 μm or more and 1.50 μm or less, 0.20 μm or more and 1.40 μm or less, 0.25 μm or more and 2.00 μm or less, 0.25 μm or more and 1.8 0 μm or less, 0.25 μm or more and 1.50 μm or less, 0.25 μm or more and 1.40 μm or less, 0.50 μm or more and 2.00 μm or less, 0.50 μm or more and 1.80 μm or less, 0.50 μm or more and 1.50 μm or less, 0.50 μm or more and 1.40 μm or less, 0.70 μm or more and 2.00 μm or less, 0.70 μm or more and 1.80 μm or less, 0.70 μm or more and 1.50 μm or less, and 0.70 μm or more and 1.40 μm or less.

[0033] In the optical film of the present disclosure, it is preferable that the element ratios obtained by analyzing the surface region on the first surface side by X-ray photoelectron spectroscopy satisfy the following formulas 2 to 4. 3.5≦F / Inorganic Si≦10.0 (Formula 2) 0.08≦Organic Si / Inorganic Si≦1.00 (Formula 3) 5.0≦F / Organic Si≦50.0 (Formula 4) [In formulas 2 to 4, "F" is the ratio of fluorine element, "inorganic Si" is the ratio of silicon element belonging to an inorganic silicon compound, and "organic Si" is the ratio of silicon element belonging to an organic silicon compound.]

[0034] In this specification, the "surface region on the first surface side" refers to a region from the surface on the first surface side to a depth of 10 nm. In this specification, "X-ray photoelectron spectroscopy" may be referred to as "XPS." The element ratio of the surface region on the first surface side can be measured, for example, by the method described in the Examples.

[0035] In the surface region of the first surface of the optical film, inorganic Si is mainly derived from silica particles, and organic Si and F are mainly derived from the leveling agent. Inorganic Si and organic Si can be separated by peak separation of inorganic and organic components from the X-ray photoelectron spectrum of the Si2p orbital.

[0036] In the surface region of the first side of the optical film, inorganic Si can reduce the refractive index of the first side, but tends to deteriorate the fingerprint wiping property. In addition, by containing a predetermined amount or more of organic Si and F relative to inorganic Si in the surface region of the first side of the optical film, the fingerprint wiping property tends to be improved. Furthermore, by containing organic Si and F in a well-balanced manner in the surface region of the first side of the optical film, the fingerprint wiping property tends to be improved. Therefore, by setting F / inorganic Si to 3.5 or more, organic Si / inorganic Si to 0.08 or more, and F / organic Si to 5.0 or more and 50.0 or less, the drop contact angle can be easily set to 30.0 degrees or more, and the fingerprint wiping property can be easily improved. Furthermore, by setting F / inorganic Si to 10.0 or less and organic Si / inorganic Si to 1.00 or less, deterioration in the coatability of the antireflection layer can be easily suppressed.

[0037] The lower limit of F / inorganic Si is more preferably 4.0 or more, and even more preferably 4.5 or more, and the upper limit is more preferably 9.0 or less, and even more preferably 8.0 or less. The lower limit of the organic Si / inorganic Si ratio is more preferably 0.10 or more, and even more preferably 0.15 or more, and the upper limit is more preferably 0.80 or less, and even more preferably 0.50 or less. The lower limit of F / organic Si is more preferably 10.0 or more, even more preferably 15.0 or more, and even more preferably 22.0 or more, and the upper limit is more preferably 40.0 or less, and even more preferably 35.0 or less.

[0038] Examples of the range of F / inorganic Si include 3.5 or more and 10.0 or less, 3.5 or more and 9.0 or less, 3.5 or more and 8.0 or less, 4.0 or more and 10.0 or less, 4.0 or more and 9.0 or less, 4.0 or more and 8.0 or less, 4.5 or more and 10.0 or less, 4.5 or more and 9.0 or less, and 4.5 or more and 8.0 or less. Examples of the range of organic Si / inorganic Si include 0.08 to 1.00, 0.08 to 0.80, 0.08 to 0.50, 0.10 to 1.00, 0.10 to 0.80, 0.10 to 0.50, 0.15 to 1.00, 0.15 to 0.80, and 0.15 to 0.50. Examples of the range of F / organic Si include 5.0 or more and 50.0 or less, 5.0 or more and 40.0 or less, 5.0 or more and 35.0 or less, 10.0 or more and 50.0 or less, 10.0 or more and 40.0 or less, 10.0 or more and 35.0 or less, 15.0 or more and 50.0 or less, 15.0 or more and 40.0 or less, 15.0 or more and 35.0 or less, 22.0 or more and 50.0 or less, 22.0 or more and 40.0 or less, and 22.0 or more and 35.0 or less.

[0039] In the optical film of the present disclosure, the ratio of inorganic Si to all elements is preferably 2 atomic % or more and 20 atomic % or less, based on the element ratio obtained by analyzing the surface region on the first surface side by X-ray photoelectron spectroscopy. By making the ratio of inorganic Si to all elements 2 atomic % or more, the refractive index of the first surface can be easily reduced, making it easier to improve the antireflection properties of the optical film. By making the ratio of inorganic Si 20 atomic % or less, it is easy to make F / inorganic Si 3.5 or more and organic Si / inorganic Si 0.08 or more. The lower limit of the proportion of inorganic Si to all elements is more preferably 3 atomic % or more, and even more preferably 4 atomic % or more, and the upper limit is more preferably 15 atomic % or less, and even more preferably 12 atomic % or less. Examples of the range of the proportion of inorganic Si to all elements include 2 atomic % or more and 20 atomic % or less, 2 atomic % or more and 15 atomic % or less, 2 atomic % or more and 12 atomic % or less, 3 atomic % or more and 20 atomic % or less, 3 atomic % or more and 15 atomic % or less, 3 atomic % or more and 12 atomic % or less, 4 atomic % or more and 20 atomic % or less, 4 atomic % or more and 15 atomic % or less, and 4 atomic % or more and 12 atomic % or less.

[0040] <Layer structure> The optical film of the present disclosure has an antireflection layer and an antiglare layer in this order from the first surface to the second surface. The outermost surface on the first surface side of the optical film is preferably the antireflection layer. The optical film of the present disclosure may have a layer other than the antireflection layer and the antiglare layer. Examples of the layer other than the antireflection layer and the antiglare layer include a substrate, an antistatic layer, and an adhesive layer. The optical film of the present disclosure preferably has, from the first surface to the second surface, an antireflection layer, an antiglare layer, and a substrate in this order.

[0041] 《Base material》 For ease of production and handling, the optical film preferably has a substrate.

[0042] The substrate is preferably one that has light transmittance, smoothness, heat resistance, and excellent mechanical strength. Examples of such substrates include plastic films such as polyester, triacetyl cellulose (TAC), cellulose diacetate, cellulose acetate butyrate, polyamide, polyimide, polyethersulfone, polysulfone, polypropylene, polymethylpentene, polyvinyl chloride, polyvinyl acetal, polyether ketone, polymethyl methacrylate, polycarbonate, polyurethane, and amorphous olefin (Cyclo-Olefin-Polymer: COP). The substrate may be one in which two or more plastic films are laminated together. Among plastic films, stretched polyester films are preferred for their mechanical strength and dimensional stability, and biaxially stretched polyester films are more preferred. Examples of polyester films include polyethylene terephthalate films and polyethylene naphthalate films. TAC films and acrylic films are preferred because they are easy to improve light transmittance and optical isotropy. COP films and polyester films are preferred because they have excellent weather resistance.

[0043] The thickness of the substrate is preferably 5 μm or more and 300 μm or less, more preferably 20 μm or more and 200 μm or less, and even more preferably 30 μm or more and 120 μm or less. When it is desired to make the optical film thinner, the upper limit of the thickness of the substrate is preferably 100 μm or less, more preferably 80 μm or less. When the substrate is a low moisture permeable substrate such as polyester, COP, acrylic, etc., the upper limit of the thickness of the substrate for thinning is preferably 60 μm or less, more preferably 40 μm or less. Even in the case of a large screen, if the upper limit of the thickness of the substrate is within the above-mentioned range, it is also preferable in that distortion is less likely to occur. The thickness of the substrate can be measured, for example, by a film thickness measuring device. Examples of film thickness measuring devices include Mitutoyo's Digimatic Standard Outside Micrometer (product number: MDC-25SX). The thickness of the substrate may be determined by measuring any ten points and averaging the measured value as described above.

[0044] The substrate preferably has a total light transmittance according to JIS K7361-1:1997 of 70% or more, more preferably 80% or more, and even more preferably 85% or more. The substrate preferably has a haze according to JIS K7136:2000 of 10% or less, more preferably 5% or less, and even more preferably 3% or less.

[0045] The surface of the substrate may be subjected to a physical treatment such as corona discharge treatment or a chemical treatment in order to improve adhesion. The substrate may have an easy-adhesion layer on the surface.

[0046] 《Anti-glare layer》 The antiglare layer is a layer that plays a central role in providing antiglare properties. The antiglare layer can be formed, for example, by (A) a method using an embossing roll, (B) an etching treatment, (C) molding with a mold, (D) formation of a coating film by coating, etc. In order to easily obtain a stable surface shape, (C) molding with a mold is preferred, and (D) formation of a coating film by coating is preferred for productivity and compatibility with a wide variety of products.

[0047] In the method (C), for example, the antiglare layer can be formed by pouring a resin into a mold and removing the molded resin from the mold. The molded resin removed from the mold may be disposed on a substrate. The mold used has an inverted surface shape of the antiglare layer. Such a mold can be prepared, for example, by the following methods (c1-1) to (c1-2) or (c2). (c1-1) A shape in which Vvv etc. fall within a specified range is created by simulation. Furthermore, the simulated shape is inverted. (c1-2) A mold is obtained by engraving the metal surface with laser light or processing the metal surface by photolithography so that the inverted shape is reflected.

[0048] (c2) A mold having an inverted shape of the antiglare layer produced in (D) is obtained by a general-purpose electroforming method.

[0049] When the antiglare layer is formed by (D), for example, the following means (d1) and (d2) can be mentioned. (d1) is preferable to (d2) in that the range of the surface shape such as Vvv can be easily adjusted. (d1) A means for forming an antiglare layer having irregularities based on the particles by applying a coating liquid containing a binder resin and particles and drying it. (d2) A method of applying a coating liquid containing a resin and a resin having poor compatibility with the resin, thereby forming unevenness by phase separation of the resin.

[0050] -Thickness- The thickness T of the antiglare layer is preferably from 2.0 μm to 10.0 μm, more preferably from 3.0 μm to 8.0 μm, and even more preferably from 4.0 μm to 6.0 μm, in order to balance curl suppression, mechanical strength, hardness, and toughness. The thickness of the antiglare layer can be calculated by, for example, averaging 20 arbitrary points selected from a cross-sectional photograph of the optical film taken by a scanning transmission electron microscope. The acceleration voltage of the STEM is preferably 10 kV to 30 kV, and the magnification of the STEM is preferably 1000 times to 7000 times.

[0051] -component- The antiglare layer preferably mainly contains a resin component. The antiglare layer further preferably contains additives such as organic particles, inorganic particles, nanometer-sized particles, refractive index adjusters, antistatic agents, leveling agents, ultraviolet absorbers, light stabilizers, antioxidants, viscosity adjusters, and thermal polymerization initiators, as necessary.

[0052] The antiglare layer preferably contains a binder resin and particles. The particles include organic particles and inorganic particles, and inorganic particles are preferred. That is, the antiglare layer preferably contains a binder resin and inorganic particles. Furthermore, the antiglare layer more preferably contains a binder resin, inorganic particles, and organic particles.

[0053] -particle- Examples of inorganic particles include silica, alumina, zirconia, titania, etc., and silica is preferred. Among inorganic particles, amorphous inorganic particles are preferred, and amorphous silica is more preferred. Examples of organic particles include particles containing one or more resins selected from polymethyl methacrylate, polyacrylic-styrene copolymer, melamine resin, polycarbonate, polystyrene, polyvinyl chloride, benzoguanamine-melamine-formaldehyde condensate, silicone, fluorine-based resin, polyester-based resin, and the like.

[0054] The term "irregularly shaped inorganic particles" refers to inorganic particles having no specific shape that are obtained by crushing large-diameter inorganic particles and then classifying them.

[0055] The particles preferably include inorganic particles. The particles more preferably include amorphous inorganic particles, and further preferably include amorphous inorganic particles and organic particles. The amorphous inorganic particles are preferably amorphous silica.

[0056] Irregular inorganic particles tend to increase Vvv and decrease Sal compared to spherical particles. However, if the particle size distribution of the irregular inorganic particles is too wide, Vvv is likely to increase, and fingerprint wiping property is likely to decrease. In particular, if the irregular inorganic particles aggregate, Vvv becomes larger, and fingerprint wiping property is likely to decrease. On the other hand, if the particle size distribution of the irregular inorganic particles is too narrow, the coating suitability is likely to decrease. For this reason, it is preferable that the volume-based cumulative distribution of particle size of the irregular inorganic particles is in the range described below. However, inorganic particles are prone to aggregation when used alone. Therefore, in order to set Vvv to the above range and to easily improve fingerprint wiping property, it is preferable to set the particle size distribution of the irregular particles to the range described below and to use organic particles in combination.

[0057] It is preferable that the volume-based cumulative distribution d10 of particle diameters, the volume-based cumulative distribution d50 of particle diameters, and the volume-based cumulative distribution d90 of particle diameters of inorganic particles such as amorphous inorganic particles satisfy the following relationships (1) and (2). 1.5≦d50 / d10≦4.0 (1) 1.0≦d90 / d50≦3.0 (2)

[0058] A d50 / d10 of 1.5 or more means that the particle size distribution of inorganic particles is wide in the region where the particle size is below the average. By making the d50 / d10 1.5 or more, it becomes easier to impart fine irregularities to the irregular surface, making it easier to reduce Sal. By making the d50 / d10 4.0 or less, it is possible to suppress an increase in the amount of inorganic particles embedded in the antiglare layer, and to increase the efficiency of adding inorganic particles. A d90 / d50 of 1.0 or more means that the particle size distribution of inorganic particles is wide in the region where the particle size is above the average. By making d90 / d50 1.0 or more, it is easy to increase Vvv and Sal. By making d90 / d50 3.0 or less, it is easy to prevent Vvv and Sal from becoming too large.

[0059] The lower limit of d50 / d10 is more preferably 1.8 or more, and even more preferably 2.0 or more, and the upper limit is more preferably 3.5 or less, and even more preferably 3.0 or less. The lower limit of d90 / d50 is more preferably 1.3 or more, and even more preferably 1.5 or more, and the upper limit is more preferably 2.5 or less, and even more preferably 2.0 or less. The d10, d50 and d90 of inorganic particles such as amorphous inorganic particles can be measured by a laser diffraction method.

[0060] The inorganic particles such as amorphous inorganic particles preferably have a volume-based cumulative particle diameter distribution d50 of 2.5 μm or more and 5.5 μm or less, more preferably 3.0 μm or more and 5.0 μm or less, and even more preferably 3.3 μm or more and 4.7 μm or less. By setting d50 to 2.5 μm or more, the number of inorganic particles can be prevented from increasing too much, making it easier to prevent Sal from becoming too small. By setting d50 to 5.5 μm or less, the number of inorganic particles can be prevented from decreasing too much, making it easier to prevent Sal from becoming too large. In addition, by preventing the number of inorganic particles from decreasing too much, valleys can be easily formed between the particles, making it easier to increase Vvv. The thickness T of the antiglare layer and the d50 of the inorganic particles such as amorphous inorganic particles are preferably 0.55 or more and 1.00 or less, more preferably 0.60 or more and 0.95 or less, and even more preferably 0.70 or more and 0.90 or less. By setting d50 / T to 0.55 or more, it becomes easier to increase Sal. By setting d50 / T to 1.00 or less, it becomes easier to decrease Sal.

[0061] The thickness T of the antiglare layer and the d90 of the inorganic particles such as amorphous inorganic particles are such that d90 / T is preferably 1.00 or more and 1.50 or less, more preferably 1.08 or more and 1.45 or less, and even more preferably 1.20 or more and 1.40 or less. By making d90 / T 1.00 or more, it becomes easier to increase Vmp. By making d90 / T 1.50 or less, it becomes easier to decrease Vmp.

[0062] The content of inorganic particles such as amorphous inorganic particles is preferably 8 parts by mass or more and 40 parts by mass or less, more preferably 12 parts by mass or more and 30 parts by mass or less, and even more preferably 15 parts by mass or more and 28 parts by mass or less, relative to 100 parts by mass of the binder resin. By making the content of inorganic particles such as amorphous inorganic particles 8 parts by mass or more, the number of inorganic particles can be prevented from decreasing too much, so that the inorganic particles are densely arranged and valleys are formed between the inorganic particles. As a result, Vvv becomes a predetermined value or more, and further, Sal does not become too large, so that the antiglare property can be easily improved. By setting the content of inorganic particles such as amorphous inorganic particles to 40 parts by mass or less, it is possible to prevent the number of inorganic particles from increasing too much, and therefore it is possible to easily prevent Sal from becoming too small.

[0063] The content of the organic particles is preferably 1 part by mass or more and 25 parts by mass or less, more preferably 3 parts by mass or more and 18 parts by mass or less, and even more preferably 8 parts by mass or more and 14 parts by mass or less, relative to 100 parts by mass of the binder resin. By making the content of organic particles 1 part by mass or more, it is possible to easily suppress the aggregation of inorganic particles. In addition, by making the content of organic particles 1 part by mass or more, it is possible to prevent the number of organic particles from being reduced too much, which makes it easier to form valleys between particles. This makes it easier to increase Vvv. Note that when the number of particles is reduced, Vmp tends to increase. Since organic particles have a relatively uniform particle size distribution, an increase in the content of organic particles leads to a stronger tendency for Sal to become smaller. Therefore, by setting the content of organic particles to 25 parts by mass or less, it is possible to prevent Sal from becoming too small, and to facilitate good fingerprint wiping-off properties.

[0064] The average particle size of the organic particles is preferably from 1.0 μm to 5.0 μm, more preferably from 1.2 μm to 3.0 μm, and even more preferably from 1.3 μm to 2.5 μm. By setting the average particle diameter of the organic particles to 1.0 μm or more, it is possible to prevent the number of organic particles from increasing too much, and therefore it is possible to easily prevent Sal from becoming too small. Therefore, by setting the average particle diameter of the organic particles to 1.0 μm or more, it is possible to easily improve the fingerprint wiping property. By setting the average particle diameter of the organic particles to 5.0 μm or less, it is possible to prevent the number of organic particles from decreasing too much, and therefore it is possible to easily form a valley between the particles. Therefore, it is possible to easily increase Vvv. Note that when the number of particles decreases, Vmp tends to increase. In this specification, the average particle size of organic particles means a value determined as a volume average value d50 by a laser diffraction method.

[0065] The organic particles preferably have a narrow particle size distribution. Specifically, the ratio of particles within the range of ±0.5 μm of the average particle size of the organic particles is preferably 80% by volume or more, more preferably 85% by volume or more, and even more preferably 90% by volume or more of the total amount of the organic particles. By narrowing the particle size distribution of the organic particles, organic particles of uniform particle size are densely arranged, making it easier to suppress Vvv from becoming too large. The shape of the organic particles may be spherical, discoid, rugby ball-like, irregular, etc. Among these shapes, spherical organic particles are preferred because the particle size distribution is easily controlled.

[0066] The average particle size of the organic particles relative to the thickness of the antiglare layer (average particle size of the organic particles / thickness of the antiglare layer) is preferably 0.20 to 0.70, more preferably 0.23 to 0.50, and even more preferably 0.25 to 0.35. By setting the average particle size of the organic particles / thickness of the antiglare layer in the above range, Vvv and Sal can be easily set in the above range.

[0067] -Inorganic fine particles- The antiglare layer may further contain inorganic fine particles in addition to the binder resin and the particles. In this specification, the inorganic fine particles and the above-mentioned particles can be distinguished from each other by the average particle size. By including inorganic fine particles in the antiglare layer, the difference between the refractive index of the particles and the refractive index of the composition of the antiglare layer other than the particles becomes smaller, making it easier to reduce internal haze.

[0068] Examples of inorganic fine particles include fine particles made of silica, alumina, zirconia, titania, etc. Among these, silica is preferable because it is easy to suppress the generation of internal haze.

[0069] The average particle size of the inorganic fine particles is preferably from 1 nm to 200 nm, more preferably from 2 nm to 100 nm, and even more preferably from 5 nm to 50 nm.

[0070] - Binder resin - In order to facilitate good scratch resistance, the binder resin preferably contains a cured product of a curable resin composition, such as a cured product of a thermosetting resin composition or a cured product of an ionizing radiation curable resin composition, and more preferably contains a cured product of an ionizing radiation curable resin composition. The binder resin may contain a thermoplastic resin as long as the effects of the present disclosure are not impaired.

[0071] In order to facilitate achieving good scratch resistance, the ratio of the cured product of the curable resin composition to the total amount of the binder resin is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 100% by mass.

[0072] The thermosetting resin composition is a composition that contains at least a thermosetting resin, and is a resin composition that is cured by heating. Examples of the thermosetting resin include acrylic resin, urethane resin, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, silicone resin, etc. In the thermosetting resin composition, a curing agent is added to the curable resin as required.

[0073] The ionizing radiation curable resin composition is a composition containing a compound having an ionizing radiation curable functional group (hereinafter, also referred to as "ionizing radiation curable compound"). Examples of the ionizing radiation curable functional group include ethylenically unsaturated bond groups such as (meth)acryloyl group, vinyl group, and allyl group, as well as epoxy group and oxetanyl group. As the ionizing radiation curable compound, a compound having an ethylenically unsaturated bond group is preferred, a compound having two or more ethylenically unsaturated bond groups is more preferred, and among them, a polyfunctional (meth)acrylate-based compound having two or more ethylenically unsaturated bond groups is even more preferred. As the polyfunctional (meth)acrylate-based compound, either a monomer or an oligomer can be used. Ionizing radiation refers to electromagnetic waves or charged particle beams that have an energy quantum capable of polymerizing or crosslinking molecules. Usually, ultraviolet (UV) rays or electron beams (EB) are used, but other types of electromagnetic waves such as X-rays and gamma rays, as well as charged particle beams such as alpha rays and ion beams can also be used.

[0074] Among the polyfunctional (meth)acrylate compounds, examples of bifunctional (meth)acrylate monomers include ethylene glycol di(meth)acrylate, bisphenol A tetraethoxydiacrylate, bisphenol A tetrapropoxydiacrylate, and 1,6-hexanediol diacrylate. Examples of trifunctional or higher (meth)acrylate monomers include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol tetra(meth)acrylate, and isocyanuric acid-modified tri(meth)acrylate. The (meth)acrylate monomer may have a part of its molecular skeleton modified, for example, with ethylene oxide, propylene oxide, caprolactone, isocyanuric acid, alkyl, cyclic alkyl, aromatic, bisphenol, or the like.

[0075] Examples of the polyfunctional (meth)acrylate oligomer include acrylate polymers such as urethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, and polyether (meth)acrylate. The urethane (meth)acrylate can be obtained, for example, by reacting a polyhydric alcohol and an organic diisocyanate with a hydroxy (meth)acrylate. Preferred epoxy (meth)acrylates are (meth)acrylates obtained by reacting a tri- or higher functional aromatic epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin, or the like, with (meth)acrylic acid, (meth)acrylates obtained by reacting a di- or higher functional aromatic epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin, or the like, with a polybasic acid and (meth)acrylic acid, and (meth)acrylates obtained by reacting a di- or higher functional aromatic epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin, or the like, with a phenol and (meth)acrylic acid.

[0076] The weight average molecular weight of the polyfunctional (meth)acrylate oligomer is preferably 500 or more and 3,000 or less, and more preferably 700 or more and 2,500 or less. In this specification, the weight average molecular weight is an average molecular weight measured by GPC analysis and converted into standard polystyrene.

[0077] In addition, a monofunctional (meth)acrylate may be used in combination as an ionizing radiation curable compound for the purpose of adjusting the viscosity of the antiglare layer coating solution, etc. Examples of the monofunctional (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and isobornyl (meth)acrylate. The above ionizing radiation curable compounds may be used alone or in combination of two or more.

[0078] When the ionizing radiation curable compound is an ultraviolet ray curable compound, the ionizing radiation curable composition preferably contains additives such as a photopolymerization initiator and a photopolymerization accelerator. The photopolymerization initiator may be one or more selected from acetophenone, benzophenone, α-hydroxyalkylphenone, Michler's ketone, benzoin, benzyl dimethyl ketal, benzoyl benzoate, α-acyloxime ester, thioxanthones, and the like. The photopolymerization accelerator can reduce the inhibition of polymerization caused by air during curing and increase the curing speed. Examples of the accelerator include p-dimethylaminobenzoic acid isoamyl ester and p-dimethylaminobenzoic acid ethyl ester.

[0079] When the binder resin contains a cured product of an ionizing radiation curable resin composition, the ionizing radiation curable resin composition preferably contains a polyfunctional (meth)acrylate monomer and a polyfunctional (meth)acrylate oligomer. The mass ratio of the polyfunctional (meth)acrylate monomer to the polyfunctional (meth)acrylate oligomer is preferably from 5:95 to 60:40, more preferably from 20:80 to 60:40, and further preferably from 40:60 to 60:40. By adjusting the polyfunctional (meth)acrylate monomer to a predetermined ratio or more, it becomes easier to improve the scratch resistance of the antiglare layer. By making the polyfunctional (meth)acrylate oligomer have a predetermined ratio or more, the viscosity of the coating liquid for the antiglare layer can be increased, and it is easy to prevent the particles from sinking below the antiglare layer, and it is easy to prevent the binder resin from flowing down between the protrusions based on the particles. Therefore, it is easy to make Vvv a predetermined value or more, and Sal a predetermined value or less. On the other hand, if the ratio of the polyfunctional (meth)acrylate oligomer is too high, the strength of the antiglare layer may decrease. In addition, if the viscosity of the coating liquid for the antiglare layer is too high, Vmp may become too large or Sal may become too small. For this reason, it is preferable that the ionizing radiation curable resin composition contains a predetermined amount of polyfunctional (meth)acrylate oligomer and a predetermined amount of polyfunctional (meth)acrylate monomer.

[0080] -Solvent and drying conditions- The coating solution for the antiglare layer preferably contains a solvent to adjust the viscosity and to make each component soluble or dispersible. Since the surface shape of the antiglare layer after coating and drying varies depending on the type of solvent, it is preferable to select the solvent in consideration of the saturated vapor pressure of the solvent, the permeability of the solvent into the substrate, etc. Specifically, examples of the solvent include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone (MIBK), cyclohexanone, etc.), ethers (dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexane, etc.), alicyclic hydrocarbons (cyclohexane, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated carbons (dichloromethane, dichloroethane, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.), alcohols (isopropanol, butanol, cyclohexanol, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.), glycol ethers (propylene glycol monomethyl ether acetate, etc.), cellosolve acetates, sulfoxides (dimethyl sulfoxide, etc.), amides (dimethylformamide, dimethylacetamide, etc.), and mixtures of these may also be used.

[0081] The solvent in the coating solution for the antiglare layer is preferably a solvent with a high evaporation rate as a main component. By increasing the evaporation rate of the solvent, it is possible to suppress the particles from sinking to the bottom of the antiglare layer, and furthermore, to easily suppress the binder resin from flowing down between the protrusions based on the particles. Therefore, it is easy to make Vvv equal to or higher than a predetermined value, and Sal equal to or lower than a predetermined value. The term "main component" means that the solvent accounts for 50% by mass or more of the total amount of the solvent, preferably 70% by mass or more, more preferably 90% by mass or more, and further preferably 97% by mass or more. In this specification, a solvent having a fast evaporation rate means a solvent having an evaporation rate of 100 or more, where the evaporation rate of butyl acetate is taken as 100. The evaporation rate of a solvent having a fast evaporation rate is more preferably 120 or more and 300 or less, and even more preferably 150 or more and 220 or less. Examples of solvents with a fast evaporation rate include methyl isobutyl ketone (evaporation rate 160), toluene (evaporation rate 200), and methyl ethyl ketone (evaporation rate 370). On the other hand, examples of solvents with slow evaporation rates of less than 100 include cyclohexanone (evaporation rate 32) and propylene glycol monomethyl ether acetate (evaporation rate 44).

[0082] When the antiglare layer is formed from the coating liquid for the antiglare layer, it is preferable to control the drying conditions. The drying conditions can be controlled by the drying temperature and the wind speed in the dryer. The drying temperature is preferably 30° C. or higher and 120° C. or lower, and the drying wind speed is preferably 0.2 m / s or higher and 50 m / s or lower. In order to control the surface shape of the antiglare layer by drying, it is preferable to irradiate the antiglare layer with ionizing radiation after drying the coating solution. The drying conditions are preferably two-stage drying in the above temperature range and wind speed range. The drying temperature in the second stage is preferably higher and the wind speed is stronger than that in the first stage. By drying slowly in the first stage, when the surface of the amorphous inorganic particles is covered with the binder resin, the shape of the amorphous inorganic particles can be easily reflected on the surface of the binder resin. In addition, by setting the drying temperature in the second stage higher than that in the first stage and increasing the wind speed, the aggregation of the organic particles can be easily suppressed, and the organic particles can be easily arranged densely. Therefore, by performing two-stage drying, it is easy to make Vvv equal to or higher than a predetermined value and Sal equal to or lower than a predetermined value. In the first stage drying, the drying temperature is preferably 30° C. or more and less than 60° C., and the drying wind speed is preferably 0.2 m / s or more and less than 7 m / s. In the second stage drying, the drying temperature is preferably 60° C. or more and 120° C. or less, and the drying wind speed is preferably 7 m / s or more and 50 m / s or less.

[0083] 《Anti-reflection layer》 The antireflection layer is preferably located on the outermost surface on the first surface side. Examples of the antireflection layer include a single-layer structure of a low refractive index layer, a two-layer structure of a high refractive index layer and a low refractive index layer, and a multi-layer structure of three or more layers. The low refractive index layer and the high refractive index layer can be formed by a general-purpose wet method or dry method. In the case of the wet method, the single-layer structure or two-layer structure is preferable, and in the case of the dry method, the multi-layer structure is preferable. The wet method is superior to the dry method in terms of production efficiency and chemical resistance. In the optical film of the present disclosure, in order to easily maintain the uneven shape of the antiglare layer, the antireflection layer preferably has a single-layer structure of a low refractive index layer.

[0084] --Single-layer or two-layer structure-- The single layer structure is a single layer of a low refractive index layer, and the two-layer structure is formed from a high refractive index layer and a low refractive index layer. The single layer structure or the two-layer structure is preferably formed by a wet method. Examples of methods for forming an antireflection layer by a wet method include a method of forming the antireflection layer by a sol-gel method using a metal alkoxide or the like, a method of forming the antireflection layer by coating a resin having a low refractive index such as a fluororesin, and a method of forming the antireflection layer by coating a coating liquid in which low refractive index particles or high refractive index particles are contained in a binder resin composition. Among the wet methods, it is preferable to form an antireflection layer by applying a coating liquid of low-refractive index particles or high-refractive index particles to a binder resin composition for the purpose of adhesion and scratch resistance. That is, the low-refractive index layer preferably contains a binder resin and low-refractive index particles. Also, the high-refractive index layer preferably contains a binder resin and high-refractive index particles.

[0085] The lower limit of the refractive index of the low refractive index layer is preferably 1.10 or more, more preferably 1.20 or more, more preferably 1.26 or more, more preferably 1.28 or more, and more preferably 1.30 or more, and the upper limit is preferably 1.48 or less, more preferably 1.45 or less, more preferably 1.40 or less, more preferably 1.38 or less, and more preferably 1.32 or less. In this specification, the refractive index refers to the value at a wavelength of 550 nm.

[0086] The lower limit of the thickness of the low refractive index layer is preferably 80 nm or more, more preferably 85 nm or more, and more preferably 90 nm or more, and the upper limit is preferably 150 nm or less, more preferably 110 nm or less, and more preferably 105 nm or less.

[0087] In order to improve scratch resistance, the binder resin of the low refractive index layer preferably contains a cured product of a curable resin composition such as a cured product of a thermosetting resin composition or a cured product of an ionizing radiation curable resin composition, and more preferably contains a cured product of an ionizing radiation curable resin composition. The binder resin of the low refractive index layer may contain a thermoplastic resin as long as the effects of the present disclosure are not impaired.

[0088] Examples of the cured product of the curable resin composition for the low refractive index layer include the same cured products of the curable resin composition as exemplified for the antiglare layer. The proportion of the cured product of the curable resin composition relative to the total amount of the binder resin in the low refractive index layer is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 97% by mass or more.

[0089] The binder resin of the low refractive index layer may contain a thermoplastic resin. By containing a thermoplastic resin as the binder resin, the viscosity of the coating liquid for the low refractive index layer is increased, and the coating liquid for the low refractive index layer is less likely to flow down between the convex parts of the antiglare layer. Therefore, by containing a thermoplastic resin as the binder resin, Vvv can be easily set to a predetermined value or more, and Sal can be easily set to a predetermined value or less. Furthermore, since organic Si and fluorine are easily left in the vicinity of the surface of the first side, the element ratios of formulas 2 to 4 can be easily satisfied. On the other hand, if the viscosity of the coating liquid for the low refractive index layer becomes too high, defects may occur on the surface of the antiglare layer when the coating liquid for the antireflection layer is applied. Due to the above-mentioned effects and coating strength, the content of the thermoplastic resin is preferably from 0.1 to 3.0 mass% of the total amount of the binder resin, more preferably from 0.2 to 1.5 mass%, and even more preferably from 0.3 to 0.7 mass%.

[0090] Examples of thermoplastic resins include polystyrene-based resins, polyolefin-based resins, ABS resins (including heat-resistant ABS resins), AS resins, AN resins, polyphenylene oxide-based resins, polycarbonate-based resins, polyacetal-based resins, acrylic-based resins, polyethylene terephthalate-based resins, polybutylene terephthalate-based resins, polysulfone-based resins, and polyphenylene sulfide-based resins, with acrylic resins being preferred from the viewpoint of transparency. The weight average molecular weight of the thermoplastic resin is preferably 20,000 or more and 200,000 or less, more preferably 30,000 or more and 150,000 or less, and even more preferably 50,000 or more and 100,000 or less.

[0091] The low refractive index particles include hollow particles and solid particles. The low refractive index particles may contain only either hollow particles or solid particles, but it is preferable to contain hollow particles in order to lower the refractive index. In order to suppress the decrease in the coating strength of the low refractive index layer, solid particles may be contained in addition to hollow particles. Note that by containing only hollow particles without containing solid particles, the effect of the present disclosure can be easily achieved. The material of the hollow particles and solid particles may be any of inorganic compounds such as silica and magnesium fluoride, or organic compounds, but silica is preferred for lowering the refractive index and strength. That is, the low refractive index layer preferably contains hollow silica particles. It is also preferred that the low refractive index layer further contains solid silica particles in addition to the hollow silica particles.

[0092] The average primary particle diameter of the hollow particles is preferably smaller than the thickness of the low refractive index layer, for example, 1 nm to 150 nm. The average primary particle diameter of the hollow particles is preferably 35 nm to 100 nm, more preferably 50 nm to 100 nm, and even more preferably 60 nm to 80 nm. The average primary particle diameter of the solid particles is preferably smaller than the thickness of the low refractive index layer, for example, 0.5 nm to 100 nm. The average primary particle diameter of the solid particles is preferably 1 nm to 30 nm, more preferably 5 nm to 20 nm, and even more preferably 10 nm to 15 nm.

[0093] The average primary particle diameters of the hollow particles, solid particles described later, and highly refractive particles described later can be calculated by the following steps (A1) to (A3). (A1) The cross section of the antireflection member is imaged by a TEM or STEM. The acceleration voltage of the TEM or STEM is preferably 10 kv to 30 kV, and the magnification is preferably 50,000 to 300,000. (A2) Randomly extract 10 particles from the observed image, and calculate the particle diameter of each particle. The particle diameter is measured as the distance between two parallel lines that is the maximum distance between the two lines when the cross section of the particle is sandwiched between the two lines. (A3) The same procedure is carried out five times on separate observation images of the same sample, and the value obtained from the number average of the particle sizes of a total of 50 particles is regarded as the average primary particle size of the particles.

[0094] The higher the content of hollow particles, the higher the filling rate of the hollow particles in the binder resin, and the lower the refractive index of the low refractive index layer. Therefore, the content of hollow particles is preferably 100 parts by mass or more, more preferably 150 parts by mass or more, per 100 parts by mass of the binder resin. On the other hand, if the content of hollow particles is too high, the hollow particles tend to be easily damaged or dropped off, and the mechanical strength of the low refractive index layer, such as scratch resistance, tends to decrease. In addition, if the content of hollow particles is too high, it may be difficult to satisfy the above formulas 2 and 3. For this reason, the content of hollow particles is preferably 300 parts by mass or less, more preferably 250 parts by mass or less, relative to 100 parts by mass of the binder resin.

[0095] In order to improve the scratch resistance of the low refractive index layer, the content of the solid particles is preferably 20 parts by mass or more, and more preferably 40 parts by mass or more, based on 100 parts by mass of the binder resin. On the other hand, if the content of the solid particles is too high, the solid particles tend to aggregate. Also, if the content of the solid particles is too high, it may be difficult to satisfy the above formulas 2 and 3. Therefore, the content of the solid particles is preferably 100 parts by mass or less, more preferably 60 parts by mass or less, relative to 100 parts by mass of the binder resin.

[0096] The low refractive index layer preferably contains a leveling agent containing organic Si and fluorine so that the first surface easily satisfies the element ratios of the above formulas 2 to 4. The leveling agent containing organic Si and fluorine may be a compound containing organic Si and fluorine in the molecule. The leveling agent containing organic Si and fluorine may be a compound containing organic Si in the molecule and a compound containing fluorine in the molecule. In order to easily improve compatibility with the binder resin, the low refractive index layer preferably contains a compound containing organic Si and fluorine in one molecule as a leveling agent. The leveling agent preferably has a functional group reactive with the binder resin in the molecule. The element ratios of the above formulas 2 to 4 can be adjusted mainly by the content of the leveling agent and the ratio of organic Si and fluorine in the leveling agent. However, it is difficult to control the amount of the coating liquid for the low refractive index layer that flows down between the convex parts of the antiglare layer only by the content of the leveling agent and the ratio of organic Si and fluorine in the leveling agent. In order to easily satisfy the element ratios of the above formulas 2 to 4, it is preferable to increase the viscosity of the coating liquid for the low refractive index layer or control the drying conditions of the coating liquid for the low refractive index layer to reduce the amount of the coating liquid for the low refractive index layer that flows down between the convex parts of the antiglare layer.

[0097] The content of the leveling agent is preferably adjusted so as to satisfy the element ratios of the above formulas 2 to 4 according to the ratio of organic Si and fluorine in the leveling agent. In one embodiment of the present disclosure, the content of the leveling agent relative to the total solid content of the low refractive index layer is preferably 10% by mass or more and 40% by mass or less, more preferably 15% by mass or more and 40% by mass or less, and even more preferably 20% by mass or more and 40% by mass or less.

[0098] The high refractive index layer is preferably disposed closer to the antiglare layer than the low refractive index layer. The lower limit of the refractive index of the high refractive index layer is preferably 1.53 or more, more preferably 1.54 or more, more preferably 1.55 or more, and more preferably 1.56 or more, and the upper limit is preferably 1.85 or less, more preferably 1.80 or less, more preferably 1.75 or less, and more preferably 1.70 or less.

[0099] The upper limit of the thickness of the high refractive index layer is preferably 200 nm or less, more preferably 180 nm or less, and even more preferably 150 nm or less, and the lower limit is preferably 50 nm or more, and more preferably 70 nm or more.

[0100] The binder resin for the high refractive index layer may be the same as that for the low refractive index layer.

[0101] Examples of high refractive index particles include antimony pentoxide, zinc oxide, titanium oxide, cerium oxide, tin-doped indium oxide, antimony-doped tin oxide, yttrium oxide, and zirconium oxide. The average primary particle size of the high refractive index particles is preferably 2 nm or more, more preferably 5 nm or more, and even more preferably 10 nm or more. From the viewpoints of whitening suppression and transparency, the average primary particle size of the high refractive index particles is preferably 200 nm or less, more preferably 100 nm or less, more preferably 80 nm or less, more preferably 60 nm or less, and more preferably 30 nm or less. The content of the high refractive index particles may be set so that the refractive index of the high refractive index layer falls within the above-mentioned range.

[0102] When anti-reflection layers such as a low refractive index layer and a high refractive index layer are formed by a wet method, it is preferable to increase the viscosity of the coating liquid for the anti-reflection layer. By increasing the viscosity of the coating liquid for the anti-reflection layer, the coating liquid for the anti-reflection layer is less likely to flow down between the convex parts of the anti-glare layer, so that even if an anti-reflection layer is formed on the anti-glare layer, the surface shape of the anti-glare layer can be easily maintained. Therefore, by appropriately increasing the viscosity of the coating liquid for the anti-reflection layer, it is easy to make Vvv equal to or greater than a predetermined value and Sal equal to or less than a predetermined value. Furthermore, it is easy to make organic Si and fluorine remain near the surface of the first side, so that the element ratios of formulas 2 to 4 can be easily satisfied. For example, the viscosity of the coating liquid for the anti-reflection layer can be increased by adding a thermoplastic resin as a binder resin, increasing the proportion of an oligomer as an ionizing radiation curable resin composition, or selecting a solvent with a high viscosity as a solvent. On the other hand, if the viscosity of the coating liquid for the anti-reflection layer is too high, defects may occur on the surface of the anti-glare layer during application of the coating liquid for the anti-reflection layer. For this reason, the viscosity of the coating liquid for the antireflection layer at 23° C. is preferably 0.1 mPa·s or more and 5.0 mPa·s or less.

[0103] Examples of the solvent for the coating liquid for the antireflection layer include the same solvents as those exemplified as the solvent for the coating liquid for the antiglare layer.

[0104] When forming an antiglare layer from an antireflection layer coating liquid, it is preferable to control the drying conditions. The drying conditions can be controlled by the drying temperature and the wind speed in the dryer. The drying temperature is preferably 30° C. or higher and 70° C. or lower, and the drying wind speed is preferably 10 m / s or higher and 30 m / s or lower. By setting the drying temperature at a low temperature, the viscosity of the coating liquid for the antireflection layer can be easily increased. In addition, by increasing the wind speed, the viscosity of the coating liquid for the antireflection layer can be quickly increased. Therefore, by drying the coating liquid for the antireflection layer at a relatively low temperature and at a strong wind speed, the coating liquid for the antireflection layer can be prevented from flowing down between the convex parts of the antiglare layer. In other words, by drying the coating liquid for the antireflection layer at a relatively low temperature and at a strong wind speed, the surface shape such as Vvv of the first surface can be easily set in the above-mentioned range, and formulas 1 to 4 can be easily satisfied. The irradiation with ionizing radiation is preferably carried out after the coating solution for the antireflection layer has been dried.

[0105] --In the case of a multi-layer structure of three or more layers-- The multilayer structure preferably formed by the dry method has a structure in which high refractive index layers and low refractive index layers are alternately laminated to a total of three or more layers. Even in the multilayer structure, the low refractive index layer is preferably disposed on the outermost surface of the optical film.

[0106] The high refractive index layer preferably has a thickness of 10 nm to 200 nm, a refractive index of 2.10 to 2.40, and more preferably a thickness of 20 nm to 70 nm. The low refractive index layer preferably has a thickness of 5 nm to 200 nm, a refractive index of 1.33 to 1.53, and more preferably a thickness of 20 nm to 120 nm.

[0107] <Optical properties> The optical film has a total light reflectance R measured by the following method. SCI It is preferable that the content of the Cr content is 3.0% or less. [Total light reflectance (R SCI ) Measurement A sample is prepared by attaching a black plate to the second surface side of the optical film via a transparent adhesive. The optical film side of the sample is set as the light incident surface, and the total light reflectance (R SCI ) is measured.

[0108] R SCI By making the R of the optical film 3.0% or less, it is possible to easily increase the blackness of the black display area in an environment where light with a high illuminance is not incident on the first surface, and therefore it is possible to easily improve the contrast. SCI is more preferably 2.5% or less, and further preferably 2.0% or less. SCI The lower limit is not particularly limited, but is usually 0.1% or more.

[0109] Usually, R SCI When the reflectance ratio is set to 3.0% or less, the contrast between the reflectance ratio of the area having fingerprint components and the area not having fingerprint components becomes large, and the appearance of the optical film is likely to be significantly deteriorated. However, the optical film of the present disclosure has a high drop contact angle, which makes it easy to wipe off fingerprints. SCI Even if the thickness is 3.0% or less, deterioration in the appearance of the optical film can be easily suppressed.

[0110] R SCI is the reflected light measured by applying light from all directions to the sample surface using an integrating sphere and closing the light trap corresponding to the specular reflection direction. Representative R SCI The measuring device is configured to comply with the geometric condition c of JIS Z8722:2009. More specifically, the typical R SCI The measuring device uses D65 as the light source of the integrating sphere spectrophotometer, the position of the receiver is +8 degrees with respect to the normal line of the sample, the aperture angle of the receiver is 10 degrees, the position of the light trap is -8 degrees with respect to the normal line of the sample, and the viewing angle is 2 degrees or 10 degrees. In this specification, the viewing angle is 2 degrees. An example of a measuring device that satisfies the above conditions is an integrating sphere spectrophotometer manufactured by Konica Minolta (product name: CM-2002).

[0111] The difference between the refractive index of the transparent adhesive of the sample and the refractive index of the layer on the second surface side of the optical film is preferably within 0.05, more preferably within 0.03, and even more preferably within 0.01. The difference between the refractive index of the transparent adhesive of the sample and the refractive index of the binder resin of the black board is preferably within 0.05, more preferably within 0.03, and even more preferably within 0.01.

[0112] The optical film preferably has a total light transmittance according to JIS K7361-1:1997 of 80% or more, more preferably 85% or more, and even more preferably 90% or more. The light incident surface when measuring the total light transmittance and haze is the second surface side of the optical film.

[0113] The optical film preferably has a haze according to JIS K7136:2000 of 20% or more and 75% or less. The lower limit of the haze is more preferably 30% or more, even more preferably 40% or more, and even more preferably 50% or more, and the upper limit is more preferably 70% or less, and even more preferably 65% ​​or less. By setting the haze to 20% or more, it is possible to easily improve antiglare properties, and by setting the haze to 75% or less, it is possible to easily suppress a decrease in image resolution. Examples of the haze of the optical film include 20% or more and 75% or less, 20% or more and 70% or less, 20% or more and 65% or less, 30% or more and 75% or less, 30% or more and 70% or less, 30% or more and 65% or less, 40% or more and 75% or less, 40% or more and 70% or less, 40% or more and 65% or less, 50% or more and 75% or less, 50% or more and 70% or less, and 50% or more and 65% or less.

[0114] In order to facilitate good image resolution and contrast, the optical film preferably has an internal haze of 20% or less, more preferably 15% or less, and even more preferably 10% or less. The internal haze can be measured by a general-purpose method, for example, by bonding a transparent sheet onto the first surface of the optical film via a transparent adhesive layer, thereby eliminating any irregularities on the first surface.

[0115] The optical film has a transmission image clarity of C when the optical comb width is 0.125 mm, measured in accordance with JIS K7374:2007. 0.125 , the transmitted image clarity when the optical comb width is 0.25 mm is C 0.25 , the transmitted image clarity when the optical comb width is 0.5 mm is C 0.5 , the transmitted image clarity when the optical comb width is 1.0 mm is C 1.0 , the transmitted image clarity when the optical comb width is 2.0 mm is C 2.0 When we define 0.125 , C 0.25 , C 0.5 , C 1.0 and C 2.0 It is preferable that the value is in the following range: C 0.125 In order to improve the antiglare property, it is preferably 50% or less, more preferably 40% or less, still more preferably 30% or less, and still more preferably 20% or less. 0.125 is preferably 1.0% or more to improve the resolution. 0.125 Examples of the range include 1.0% or more and 50% or less, 1.0% or more and 40% or less, 1.0% or more and 30% or less, and 1.0% or more and 20% or less. C 0.25 In order to improve the antiglare property, it is preferably 50% or less, more preferably 40% or less, still more preferably 30% or less, and still more preferably 20% or less. 0.25 is preferably 1.0% or more to improve the resolution. 0.25 Examples of the range include 1.0% or more and 50% or less, 1.0% or more and 40% or less, 1.0% or more and 30% or less, and 1.0% or more and 20% or less. C 0.5 In order to improve the antiglare property, it is preferably 50% or less, more preferably 40% or less, still more preferably 30% or less, and still more preferably 20% or less. 0.5 is preferably 1.0% or more to improve the resolution.0.5 Examples of the range include 1.0% or more and 50% or less, 1.0% or more and 40% or less, 1.0% or more and 30% or less, and 1.0% or more and 20% or less. C 1.0 In order to improve the antiglare property, it is preferably 50% or less, more preferably 40% or less, still more preferably 30% or less, and still more preferably 20% or less. 1.0 is preferably 1.0% or more to improve the resolution. 1.0 Examples of the range include 1.0% or more and 50% or less, 1.0% or more and 40% or less, 1.0% or more and 30% or less, and 1.0% or more and 20% or less. C 2.0 In order to improve the antiglare property, it is preferably 50% or less, more preferably 40% or less, still more preferably 30% or less, and still more preferably 20% or less. 2.0 is preferably 5.0% or more to improve the resolution. 2.0 Examples of the range include 5.0% or more and 50% or less, 5.0% or more and 40% or less, 5.0% or more and 30% or less, and 5.0% or more and 20% or less.

[0116] Optical films are C 0.125 , C 0.5 , C 1.0 and C 2.0 The total is preferably 200% or less, more preferably 150% or less, more preferably 100% or less, and still more preferably 80% or less. The total is preferably 10.0% or more to improve the resolution. The range of the total may be 10.0% or more and 200% or less, 10.0% or more and 150% or less, 10.0% or more and 100% or less, or 10.0% or more and 80% or less.

[0117] <Size, shape, etc.> The optical film may be in the form of a sheet cut to a predetermined size, or in the form of a roll obtained by winding a long sheet into a roll. The size of the sheet is not particularly limited, but the maximum diameter is about 2 inches to 500 inches. The "maximum diameter" refers to the maximum length when any two points on the optical film are connected. For example, when the optical film is rectangular, the diagonal line of the area is the maximum diameter. When the optical film is circular, the diameter of the circle is the maximum diameter. The width and length of the roll are not particularly limited, but generally, the width is about 500 mm to 3000 mm, and the length is about 500 m to 5000 m. The optical film in the form of a roll can be cut into sheets according to the size of an image display device or the like. When cutting, it is preferable to remove the ends of the roll, which have unstable physical properties. The shape of the sheet is not particularly limited, and examples thereof include polygons such as triangles, rectangles, and pentagons, circles, and random, indeterminate shapes. More specifically, when the optical film is rectangular, the aspect ratio is not particularly limited as long as it does not cause any problems as a display screen. Examples include width:height = 1:1, 4:3, 16:10, 16:9, and 2:1, but in vehicle-mounted applications and digital signage that are rich in design, the aspect ratio is not limited to these.

[0118] The surface shape of the second surface of the optical film is not particularly limited, but is preferably approximately smooth. Approximately smooth means that the arithmetic mean roughness Ra according to JIS B0601:1994 at a cutoff value of 0.8 mm is less than 0.03 μm, and preferably 0.02 μm or less.

[0119] [Method of manufacturing optical film] The method for producing an optical film of the present disclosure is the method for producing an optical film of the present disclosure described above, and includes a first step of forming an antiglare layer on a substrate, and a second step of forming an antireflection layer on the antiglare layer.

[0120] The means for forming an antiglare layer on a substrate include the above-mentioned (A) a method using an embossing roll, (B) an etching treatment, (C) molding with a mold, and (D) formation of a coating film by coating. In the case of method (A), for example, a resin layer is formed on a substrate, and an embossing roll is used to apply a shape from the resin layer side, thereby forming an antiglare layer on the substrate. In the case of method (B), for example, a layer of a photocurable resin is formed on a substrate, and then photoetched, thereby forming an antiglare layer on the substrate. In the case of method (C), for example, a resin is poured into a mold, and the molded resin is removed from the mold and placed on a substrate, thereby forming an antiglare layer on the substrate. In the case of the method (D), for example, a coating film can be formed on a substrate by the above-mentioned method (d1) or (d2), thereby forming an antiglare layer on the substrate.

[0121] The method for forming the antireflection layer on the antiglare layer may be, for example, the above-mentioned wet method or dry method.

[0122] [Polarizing plate] A polarizing plate according to the present disclosure is a polarizing plate having a polarizer, a first transparent protective plate arranged on one side of the polarizer, and a second transparent protective plate arranged on the other side of the polarizer, At least one of the first transparent protective plate and the second transparent protective plate is the optical film of the present disclosure described above, and the second surface of the optical film is disposed opposite the polarizer.

[0123] <Polarizer> Examples of polarizers include sheet-type polarizers such as polyvinyl alcohol films, polyvinyl formal films, polyvinyl acetal films, and saponified ethylene-vinyl acetate copolymer films dyed with iodine or the like and stretched, wire grid-type polarizers made of a large number of metal wires arranged in parallel, coating-type polarizers coated with lyotropic liquid crystal or a dichroic guest-host material, and multilayer thin film-type polarizers. These polarizers may be reflective polarizers that have the function of reflecting polarized components that are not transmitted.

[0124] <Transparent protection plate> A first transparent protective plate is disposed on one side of the polarizer, and a second transparent protective plate is disposed on the other side of the polarizer. At least one of the first transparent protective plate and the second transparent protective plate is the optical film of the present disclosure described above. In the polarizing plate of the present disclosure, one of the first transparent protective plate and the second transparent protective plate may be the optical film of the present disclosure described above, or both of the first transparent protective plate and the second transparent protective plate may be the optical film of the present disclosure described above.

[0125] Of the first and second transparent protective plates, the transparent protective plate that is not the optical film of the present disclosure can be a general-purpose plastic film, glass, or the like.

[0126] The polarizer and the transparent protective plate are preferably attached to each other via an adhesive. A general-purpose adhesive can be used as the adhesive, and a PVA-based adhesive is preferable.

[0127] [Face plate for image display device] The face plate for an image display device according to the present disclosure is a face plate for an image display device having a protective film laminated onto a resin plate or a glass plate, the protective film being the optical film according to the present disclosure described above, and the second surface of the optical film being arranged opposite the resin plate or the glass plate.

[0128] As the resin plate or glass plate, a resin plate or glass plate that is generally used as a front plate of an image display device can be used.

[0129] The thickness of the resin plate or glass plate is preferably 10 μm or more in order to improve the strength. The upper limit of the thickness of the resin plate or glass plate is usually 5000 μm or less. In order to reduce the thickness, the upper limit of the thickness of the resin plate or glass plate is preferably 1000 μm or less, more preferably 500 μm or less, and even more preferably 100 μm or less. Examples of the range of the thickness of the resin plate or glass plate include 10 μm or more and 5000 μm or less, 10 μm or more and 1000 μm or less, 10 μm or more and 500 μm or less, and 10 μm or more and 100 μm or less.

[0130] [Image display panel] The image display panel of the present disclosure is an image display panel having a display element and an optical film arranged on the light emission surface side of the display element, and the optical film includes the optical film of the present disclosure described above (see FIG. 2).

[0131] In the image display panel, the optical film of the present disclosure is preferably disposed so that the second surface side faces the display element side. In an image display panel, the optical film of the present disclosure is preferably disposed on the outermost surface on the light exit surface side of a display element.

[0132] Examples of the display element include a liquid crystal display element, an EL display element (an organic EL display element, an inorganic EL display element), a plasma display element, and further, an LED display element such as a micro LED display element. These display elements may have a touch panel function inside the display element. Examples of the liquid crystal display mode of the liquid crystal display element include the IPS mode, VA mode, multi-domain mode, OCB mode, STN mode, and TSTN mode.

[0133] The image display panel of the present disclosure may be an image display panel with a touch panel, which has a touch panel between a display element and an optical film.

[0134] The size of the image display panel is not particularly limited, but the maximum diameter is about 2 inches to 500 inches. The maximum diameter means the maximum length when connecting any two points on the surface of the image display panel.

[0135] [Image display device] The image display device of the present disclosure includes the image display panel of the present disclosure.

[0136] The image display device of the present disclosure is not particularly limited as long as it includes the image display panel of the present disclosure. The image display device of the present disclosure preferably includes the image display panel of the present disclosure, a drive control unit electrically connected to the image display panel, and a housing that accommodates these. When the display element is a liquid crystal display element, the image display device of the present disclosure requires a backlight, which is disposed on the side opposite to the light exit surface of the liquid crystal display element.

[0137] The size of the image display device is not particularly limited, but the maximum diameter of the effective display area is about 2 inches or more and 500 inches or less. The effective display area of ​​an image display device is an area in which an image can be displayed. For example, when the image display device has a housing that surrounds a display element, the area inside the housing is the effective image area. The maximum diameter of the effective image area refers to the maximum length when any two points within the effective image area are connected. For example, if the effective image area is rectangular, the diagonal line of the area is the maximum diameter. Also, if the effective image area is circular, the diameter of the area is the maximum diameter.

[0138] [How to select optical films] The method for selecting an optical film according to the present disclosure involves selecting an optical film that satisfies the following selection conditions. (Optical film selection criteria) An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, The first surface has an uneven shape, The first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2 That's all. The drop contact angle measured by the method described below is 30.0 degrees or more. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped from a height of 45 mm onto the first surface of the optical film. The droplet is dropped perpendicularly to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method. The image display panel of the present disclosure is included.

[0139] The method for selecting an optical film of the present disclosure may have additional selection conditions. The additional selection conditions include preferred embodiments of the optical film. Examples of the additional selection conditions include the following A to D. A: Vvv / Vvc is less than 0.10. B: The optical film has, from the first surface to the second surface, the antireflection layer, the antiglare layer, and a substrate in this order. C: The element ratio satisfies the following formulas 2 to 4. 3.5≦F / Inorganic Si≦10.0 (Formula 2) 0.08≦Organic Si / Inorganic Si≦1.00 (Formula 3) 5.0≦F / Organic Si≦50.0 (Formula 4) D: Total light reflectance measured by the following method R SCI is less than 3.0%. [Total light reflectance (R SCI ) Measurement A sample is prepared by attaching a black plate to the second surface side of the optical film via a transparent adhesive. The optical film side of the sample is set as the light incident surface, and the total light reflectance (R SCI ) is measured.

[0140] According to the method for selecting an optical film of the present disclosure, an optical film having excellent antiglare properties and good fingerprint wiping properties can be efficiently selected.

[0141] [Evaluation method for fingerprint wiping off ability] The method for evaluating fingerprint wiping removability according to the present disclosure uses the drop contact angle value measured by the following measurement as an evaluation index. <Drop contact angle measurement> A droplet with a surface tension of 30 mN / m is dropped from a height of 45 mm onto the surface of the measurement object. The droplet is dropped perpendicular to the surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method.

[0142] According to the method for evaluating the fingerprint wiping property of the present disclosure, the fingerprint wiping property of a measurement object can be easily evaluated. Specifically, the smaller the drop contact angle value, the better the fingerprint wiping property can be evaluated.

[0143] This disclosure includes the following [1] to

[17] . [1] An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, The first surface has an uneven shape, The first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2 That's all. An optical film having a drop contact angle of 30.0 degrees or more as measured by the following method. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped from a height of 45 mm onto the first surface of the optical film. The droplet is dropped perpendicularly to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method. [2] The optical film according to [1], wherein the first surface has a ratio (Vvv / Vvc) of Vvv to Vvc, which is the core void volume defined in ISO 25178-2:2012, of 0.10 or less. [3] The optical film according to [1] or [2], wherein the first surface has a minimum autocorrelation length, Sal, defined in ISO 25178-2:2012, of 4.0 μm or more and 12.0 μm or less. [4] The optical film according to any one of [1] to [3], wherein the first surface has a pole height Sxp defined in ISO 25178-2:2012 of 0.15 μm or more and 2.00 μm or less. [5] The optical film according to any one of [1] to [4], wherein the optical film has, from the first surface to the second surface, the antireflection layer, the antiglare layer, and a substrate in this order. [6] The optical film according to any one of [1] to [5], wherein the antiglare layer contains a binder resin and particles. [7] The optical film according to any one of [1] to [6], wherein the element ratios obtained by analyzing the surface region on the first side by X-ray photoelectron spectroscopy satisfy the following formulas 2 to 4: 3.5≦F / Inorganic Si≦10.0 (Formula 2) 0.08≦Organic Si / Inorganic Si≦1.00 (Formula 3) 5.0≦F / Organic Si≦50.0 (Formula 4) [In formulas 2 to 4, "F" is the ratio of fluorine element, "inorganic Si" is the ratio of silicon element belonging to an inorganic silicon compound, and "organic Si" is the ratio of silicon element belonging to an organic silicon compound.] [8] The optical film according to [7], wherein, in the element ratio obtained by the analysis by X-ray photoelectron spectroscopy, the ratio of inorganic Si to all elements is 2 atomic % or more and 20 atomic % or less. [9] The optical film has a total light reflectance R measured by the following method. SCI The optical film according to any one of [1] to [8], wherein the optical film has a refractive index of 3.0% or less. [Total light reflectance (R SCI ) Measurement A sample is prepared by attaching a black plate to the second surface side of the optical film via a transparent adhesive. The optical film side of the sample is set as the light incident surface, and the total light reflectance (R SCI ) is measured.

[10] The optical film according to any one of [1] to [9], having a haze according to JIS K7136:2000 of 20% or more and 75% or less.

[11] A polarizing plate having a polarizer, a first transparent protective plate arranged on one side of the polarizer, and a second transparent protective plate arranged on the other side of the polarizer, A polarizing plate, wherein at least one of the first transparent protective plate and the second transparent protective plate is the optical film described in any one of [1] to

[10] , and the second surface of the optical film is disposed opposite the polarizer.

[12] A face panel for an image display device, comprising a protective film laminated onto a resin plate or a glass plate, the protective film being an optical film according to any one of [1] to

[10] , and the second surface of the optical film being disposed opposite the resin plate or the glass plate.

[13] An image display panel having a display element and an optical film arranged on a light exit surface side of the display element, the optical film comprising any one of the optical films according to [1] to

[10] .

[14] An image display device comprising the image display panel according to

[13] .

[15] A method for producing an optical film according to any one of [1] to

[10] , A method for producing an optical film, comprising a first step of forming an antiglare layer on a substrate, and a second step of forming an antireflection layer on the antiglare layer.

[16] A method for selecting an optical film, which selects an optical film that satisfies the following selection conditions: (Optical film selection criteria) An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, The first surface has an uneven shape, The first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2 That's all. The drop contact angle measured by the method described below is 30.0 degrees or more. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped from a height of 45 mm onto the first surface of the optical film. The droplet is dropped perpendicularly to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method.

[17] A method for evaluating fingerprint wiping removability, using the drop contact angle measured by the following method as the evaluation index. <Drop contact angle measurement> A droplet with a surface tension of 30 mN / m is dropped from a height of 45 mm onto the surface of the measurement object. The droplet is dropped perpendicular to the surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method. EXAMPLES

[0144] Next, the present disclosure will be described in more detail with reference to examples, but the present disclosure is not limited to these examples. In addition, "parts" and "%" are based on mass unless otherwise specified.

[0145] 1. Measurement and Evaluation The optical films of the examples and comparative examples were measured and evaluated as follows. The atmosphere during each measurement and evaluation was a temperature of 23±5°C and a relative humidity of 40% to 65%. Before each measurement and evaluation, the target sample was exposed to the atmosphere for 30 minutes to 60 minutes before the measurement and evaluation. The results are shown in Table 1 or 2.

[0146] 1-1. Surface shape measurement The antiglare films of the examples and comparative examples were cut to 10 cm x 10 cm. The cut locations were selected randomly after visually checking for any abnormalities such as dust or scratches. Sample 1 was produced by bonding the substrate side of the cut antiglare film to a glass plate (thickness 2.0 mm) measuring 10 cm long x 10 cm wide via an optically transparent adhesive sheet (product name: Panaclean PD-S1, thickness 25 μm) made by Panac Corporation. Using a confocal laser microscope (VK-X250 (control unit), VK-X260 (measurement unit)), sample 1 was set so that it was fixed and in close contact with the measurement stage, and then the surface shape of the first side of each sample was measured and analyzed under the following measurement condition 1, image processing condition 1, and analysis condition 1. The measurement and analysis software used was the Multifile Analysis Application (version 1.3.1.120).

[0147] (Measurement condition 1) Laser wavelength: 408nm Measurement optical system: Confocal optical system Objective lens: 150x Zoom:1x Measurement area: 93.95μm×70.44μm Number of measurement points: 1024 x 768 points Measurement conditions: Transparent object surface shape / High precision / Double scan

[0148] (Image processing condition 1) DCL / BCL: DCL=13000, BCL=65535, Processing method: Interpolate from surrounding pixels Height cut level: Strong (Analysis condition 1) ·Area: All areas Filter type: Gaussian S-filter: 0.25μm F-Operation: Plane tilt correction (area designation) L-Filter: None End effect compensation: ON s when calculating Sal: s=0.20 p, q when calculating Sxp: p=2.5%, q=50.0%

[0149] The analysis software displayed "Vvv," "Vvc," "Vmp," "Sal," and "Sxp" for each measurement area and used as the measured values.

[0150] 1-2.Contact angle <Normal contact angle> The optical films of the examples and comparative examples were cut into 10 cm squares. The substrate side of the cut optical film was attached to a glass plate (10 cm long x 10 cm wide, 2.0 mm thick) via a transparent adhesive sheet to prepare a sample for measurement. The cutting location was selected from a random location on the optical film after visually checking that there were no abnormalities such as dust or scratches. When attaching the optical film to the glass plate, care was taken to prevent wrinkles from occurring in the optical film and to prevent air bubbles from entering between the optical film and the glass plate. Using a contact angle meter (DM-300, Kyowa Interface Science Co., Ltd.), 1.0 μL of pure water was dropped onto the first surface of each sample, and the static contact angle 10 seconds after the drop landed was measured according to the θ / 2 method. When dropping the pure water, a syringe with a needle coated with fluororesin was used. <Falling contact angle> A droplet with a surface tension of 30 mN / m was placed in a syringe with a needle coated with fluororesin. A droplet with a surface tension of 30 mN / m was allowed to fall naturally from a height of 45 mm onto the first surface of each sample. The amount of the droplet that fell was 5.0 μl. The liquid used had the following composition. The droplet was allowed to fall perpendicularly to the first surface. The static contact angle 10 seconds after the droplet landed was measured using the θ / 2 method. A contact angle meter (model number: DM-300, Kyowa Interface Science Co., Ltd.) was used as the measuring device. <Liquid composition> A liquid containing 100% by mass of ethylene glycol monoethyl ether (Fujifilm Wako Pure Chemical Industries, product number: Mixture for wetting tension test No. 30)

[0151] 1-3.Element ratio Measurement pieces were cut out from the optical films of the examples and comparative examples. Using an X-ray photoelectron spectrometer, X-ray photoelectron spectra of the C1s orbital, O1s orbital, Si2p orbital, and F1s orbital of the surface region on the first side of each measurement piece were measured under the conditions described below. Peak separation was performed for each X-ray photoelectron spectrum to determine the ratio of F element, Si element, etc. In addition, the ratio of Si element belonging to inorganic silicon compound (inorganic Si) and Si element belonging to organic silicon compound (organic Si) was determined from the X-ray photoelectron spectrum of Si2p orbital. <Measurement> Equipment: Shimadzu Corporation product name "Kratos Nova" X-ray source: AlKα X-ray power: 150W Emission current: 10mA Acceleration voltage: 15 kV Measurement area: 300×700μm Charge neutralization mechanism: ON Pass energy (when measuring narrow spectrum): 40 eV

[0152] 1-4. Total light reflectance (R SCI ) The optical films of the examples and comparative examples were cut to 10 cm x 10 cm. The cut locations were selected randomly after visually checking for any abnormalities such as dust or scratches. Sample 2 was produced by bonding the substrate side of the cut optical film to a black board (Kuraray Co., Ltd., product name: Comoglass DFA2CG 502K (black) series, thickness 2 mm) measuring 10 cm long x 10 cm wide via an optically transparent adhesive sheet (product name: Panaclean PD-S1) made by Panac Corporation. Using an integrating sphere spectrophotometer (manufactured by Konica Minolta, Inc., product name: CM-2002), the total light reflectance (R SCI The illuminant of the integrating sphere spectrophotometer was D65, the receiver was positioned at +8 degrees to the normal to the sample, the aperture angle of the receiver was 10 degrees, the light trap was positioned at -8 degrees to the normal to the sample, and the viewing angle was 2 degrees.

[0153] 1-5. Haze (Hz) The optical films of the examples and comparative examples were cut into 10 cm squares. The cut locations were selected randomly after visually checking for any abnormalities such as dust or scratches. The haze of each sample was measured according to JIS K7136:2000 using a haze meter (HM-150, manufactured by Murakami Color Research Laboratory). To allow the light source to stabilize, the device was powered on and then left for 15 minutes or more, and calibration was performed without setting anything in the entrance opening, after which the measurement sample was set in the entrance opening and measurements were performed. The light incident surface was set on the substrate side. The optical films of the examples and comparative examples all had a total light transmittance of 90% or more.

[0154] 1-6. Transmitted image clarity The optical films of the examples and comparative examples were cut into 10 cm squares. The cut locations were selected at random after visually checking for any abnormalities such as dust or scratches. The transmitted image clarity of the samples was measured in accordance with JIS K7374:2007 using an image clarity measuring device (product name: ICM-1T) manufactured by Suga Test Instruments Co., Ltd. The optical comb had five widths: 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm. The light incident surface during measurement was the substrate side. C 0.125 , C 0.25 , C 0.5 , C 1.0 and C 2.0 The value of and C 0.125 , C 0.5 , C 1.0 and C 2.0 The total values ​​are shown in Table 2.

[0155] 1-7. Blackness The sample used was Sample 2 prepared in 1-4. The sample was observed in the same manner as in 1-4, except that the observer's line of sight was changed to about 160 cm from the floor. Twenty subjects evaluated the display based on the following evaluation points. The 20 subjects were five people from each age group, from their 20s to their 50s. The average score of the 20 people's evaluations was calculated and ranked according to the following criteria. The higher the rank of the following criteria, the better the blackness of the black display area. <Evaluation points> (1) No whiteness and sufficient blackness: 3 points (2) Black with a slight white tint: 2 points (3) Items that are of concern for whiteness: 1 point <Evaluation criteria> A: Average score of 2.5 or higher B: Average score is 2.0 or more but less than 2.5 C: Average score is 1.5 or more but less than 2.0 D: Average score is less than 1.5

[0156] 1-8. Anti-glare property In a bright room environment, Sample 2 prepared in 1-4 was placed on a horizontal table 70 cm high with the uneven surface facing up. The sample was placed so that it was almost directly under the illumination light. The sample was observed from the front (however, the observer was made to not block the illumination light), and the reflection of the illumination light on the uneven surface was evaluated according to the following evaluation criteria. The lighting used was a Hf32 type straight tube three-wavelength daylight fluorescent lamp, positioned 2m above the horizontal stand in the vertical direction. The illuminance on the uneven surface of the sample was evaluated in the range of 500 lux to 1000 lux. The observer's line of sight was approximately 120cm from the floor. The observer was a healthy person in their 30s with a visual acuity of 0.7 or higher. <Evaluation criteria> A: There is no outline of the light, and the position is unclear. B: There is no outline of the light, but the position is vaguely visible. C: The outline and position of the light are vaguely visible. D: The lighting outline is not very blurred and the position is clearly visible.

[0157] 1-9. Fingerprint wipe-off ability The following artificial dirt was soaked into a cloth for 10 seconds. The cloth used was "Kimtowel Wiper" manufactured by Nippon Paper Crecia Co., Ltd. Artificial dirt soaked in a cloth was applied to the rubber surface at 300g / cm 2 The rubber was cylindrical with a diameter of 12 mm. The transfer time was 5 seconds. The artificial grime transferred to the rubber surface was transferred with a load of 300 g / cm. 2 The artificial dirt was transferred to the first surface of Sample 2 with a load of 1000 g. The transfer time was 5 seconds. Using a spectrophotometer (manufactured by Konica Minolta, Inc., product name: CM-600d), the L of the total light reflection SCI of the area where the artificial dirt was transferred was measured from the first surface side of Sample 2. * Value, a * value and b * The obtained L * Value, a * value and b * Let the values ​​be L1, a1 and b1. Next, the black plate side of Sample 2 to which the artificial dirt had been transferred was attached to the base of a Gakushin abrasion tester (manufactured by Tester Sangyo Co., Ltd., product name "AB-301"). A cloth was attached to the friction element of the tester, and the artificial dirt transferred to the first surface of Sample 2 was wiped off under the wiping conditions described below. The cloth used was AS ONE Corporation's product name "ASPURE PROPREA II". Using a spectrophotometer (manufactured by Konica Minolta Inc., product name: CM-600d), the L of total light reflection SCI of the area from which the artificial dirt had been wiped off was measured from the first surface side of Sample 2. * Value, a * value and b * The obtained L * Value, a * value and b * Let the values ​​be L2, a2 ​​and b2. The color difference (ΔE) was calculated using the following formula, and the color difference value was ranked according to the following criteria. The higher the rank in the following criteria, the better the fingerprint wiping ability. ΔE={(L1-L2) 2 +(a1-a2) 2 +(b1-b2) 2} 1 / 2 <Artificial dirt> A liquid containing approximately 45% by mass of oleic acid, approximately 25% by mass of triolein, approximately 20% by mass of cholesterol oleate, approximately 4% by mass of liquid paraffin, approximately 4% by mass of squalene, and approximately 2% by mass of cholesterol (artificial sludge manufactured by Isekyusha (compliant with JIS C9606:2007 contaminated liquid)). <Wipe-off conditions> ·Moving speed: 100mm / sec ·Load: 150g / cm 2 Number of wipes: 1 each way <Evaluation criteria> A: Color difference is 2 or less B: Color difference is more than 2 and less than 4 C: Color difference is more than 4 and less than 7 D: Color difference is more than 7

[0158] 1-10. Overall rating Based on the two evaluations of anti-glare property and fingerprint wiping ability, an overall evaluation was made according to the following criteria. <Evaluation criteria> A: Both ratings are A. B: Of two ratings, one is A and one is B. C: Both of the two ratings are B. D: At least one of the two ratings is C or D.

[0159] 2. Preparation of Optical Film [Example 1] The following antiglare layer coating solution 1 was applied onto a substrate (a triacetyl cellulose resin film having a thickness of 80 μm, manufactured by Fujifilm Corporation). The substrate was then dried at 50° C. with a wind speed of 2 m / s for 40 seconds, and further dried at 70° C. with a wind speed of 15 m / s for 45 seconds. The substrate was then dried in a nitrogen atmosphere with an oxygen concentration of 200 ppm or less, with an integrated light amount of 50 mJ / cm. 2 The coated film was irradiated with ultraviolet light so as to form an antiglare layer having a thickness of 5.5 μm. Next, the following low refractive index layer coating solution 1 was applied onto the antiglare layer. Then, it was dried at 40°C with a wind speed of 20 m / s for 15 seconds, and further dried at 70°C with a wind speed of 15 m / s for 30 seconds. Then, it was dried in a nitrogen atmosphere with an oxygen concentration of 200 ppm or less with an integrated light amount of 150 mJ / cm. 2 Thus, a low refractive index layer having a thickness of 0.10 μm was formed, thereby obtaining the optical film of Example 1. The refractive index of the low refractive index layer was 1.31.

[0160] <Anti-glare layer coating solution 1> Urethane acrylate A 30 parts (Mitsubishi Chemical Corporation, product name: U-1700B: molecular weight 2,000, number of functional groups 10) Urethane acrylate B 10 parts (Shin Nakamura Chemical Industry Co., Ltd., product name: U-15HA: molecular weight 2,300, number of functional groups 15) Pentaerythritol triacrylate 60 parts (Toagosei, product name: M-305) Silica particles 23 parts (Surface-treated amorphous silica, d10: 1.2 μm, d50: 3.7 μm, d90: 6.2 μm) ·Organic particles B 8 parts (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.595) Photopolymerization initiator 5.0 parts (IGM Resins BV, product name: Omnirad184) Photopolymerization initiator 1.0 parts (IGM Resins BV, product name: Omnirad907) Silicone leveling agent 0.1 parts (Momentive Performance Materials, product name: TSF4460) Solvent (toluene) 190 parts Solvent (cyclohexanone) 5 parts Solvent (methyl isobutyl ketone) 20 parts

[0161] <Low refractive index layer coating solution 1> Multifunctional acrylate 100 parts (Manufactured by Toagosei Co., Ltd., product name "Aronix M-400") Acrylic polymer 0.5 parts (weight average molecular weight: 40,000) Hollow silica particles 180 parts (Average primary particle diameter: 75 nm, particles surface-treated with a silane coupling agent having a methacryloyl group) Fluorine-based silicone leveling agent with reactive functional groups 600 parts (Shin-Etsu Chemical Co., Ltd., product name "KY1203", solid content: 20%, solvent: methyl isobutyl ketone) Photopolymerization initiator 5.0 parts (IGM Resins, product name "Omnirad127") Solvent (methyl isobutyl ketone) 11,000 parts Solvent (1-methoxy-2-propyl acetate) 1,300 parts

[0162] [Examples 2, 3, 5, and 6] The optical films of Examples 2, 3, 5 and 6 were obtained in the same manner as in Example 1, except that the antiglare layer coating solution 1 was changed to the following antiglare layer coating solutions 2 to 5.

[0163] [Example 4] An optical film of Example 4 was obtained in the same manner as in Example 1, except that the antiglare layer coating solution 1 was changed to the antiglare layer coating solution 2 described below, and the low refractive index layer coating solution 1 was changed to the low refractive index layer coating solution 2 described below.

[0164] [Example 7] An optical film of Example 7 was obtained in the same manner as in Example 1, except that antiglare layer coating solution 1 was changed to the following antiglare layer coating solution 6 and the thickness of the antiglare layer was set to 4.8 μm.

[0165] [Example 8] An optical film of Example 8 was obtained in the same manner as in Example 1, except that the antiglare layer coating solution 1 was changed to the following antiglare layer coating solution 2, and the low refractive index layer coating solution 1 was changed to the following low refractive index layer coating solution 3. The refractive index of the low refractive index layer was 1.36.

[0166] [Comparative Example 1] An optical film of Comparative Example 1 was obtained in the same manner as in Example 1, except that the low refractive index layer coating solution 1 was changed to the following low refractive index layer coating solution 4.

[0167] [Comparative Examples 2 to 3] Optical films of Comparative Examples 2 and 3 were obtained in the same manner as in Comparative Example 1, except that antiglare layer coating solution 1 was changed to the following antiglare layer coating solutions 2 and 3.

[0168] [Comparative Example 4] An optical film of Comparative Example 4 was obtained in the same manner as in Example 1, except that antiglare layer coating solution 1 was changed to the following antiglare layer coating solution 7 and the thickness of the antiglare layer was set to 5.0 μm.

[0169] <Anti-glare layer coating solution 2> Urethane acrylate A 30 parts (Mitsubishi Chemical Corporation, product name: U-1700B: molecular weight 2,000, number of functional groups 10) Urethane acrylate B 10 parts (Shin Nakamura Chemical Industry Co., Ltd., product name: U-15HA: molecular weight 2,300, number of functional groups 15) Pentaerythritol triacrylate 60 parts (Toagosei, product name: M-305) Silica particles 21 parts (Surface-treated amorphous silica, d10: 1.2 μm, d50: 3.7 μm, d90: 6.2 μm) ·Organic particles B 10 parts (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.595) Photopolymerization initiator 5.0 parts (IGM Resins BV, product name: Omnirad184) Photopolymerization initiator 1.0 parts (IGM Resins BV, product name: Omnirad907) Silicone leveling agent 0.1 parts (Momentive Performance Materials, product name: TSF4460) Solvent (toluene) 180 parts Solvent (cyclohexanone) 15 parts Solvent (methyl isobutyl ketone) 20 parts

[0170] <Anti-glare layer coating solution 3> Urethane acrylate A 30 parts (Mitsubishi Chemical Corporation, product name: U-1700B: molecular weight 2,000, number of functional groups 10) Urethane acrylate B 10 parts (Shin Nakamura Chemical Industry Co., Ltd., product name: U-15HA: molecular weight 2,300, number of functional groups 15) Pentaerythritol triacrylate 60 parts (Toagosei, product name: M-305) Silica particles 19 parts (Surface-treated amorphous silica, d10: 1.2 μm, d50: 3.7 μm, d90: 6.2 μm) ·3 parts of organic particles A (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.515) ·Organic particles B 5 parts (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.595) Photopolymerization initiator 5.0 parts (IGM Resins BV, product name: Omnirad184) Photopolymerization initiator 1.0 parts (IGM Resins BV, product name: Omnirad907) Silicone leveling agent 0.1 parts (Momentive Performance Materials, product name: TSF4460) Solvent (toluene) 175 parts Solvent (cyclohexanone) 15 parts Solvent (methyl isobutyl ketone) 25 parts

[0171] <Anti-glare layer coating solution 4> Urethane acrylate A 30 parts (Mitsubishi Chemical Corporation, product name: U-1700B: molecular weight 2,000, number of functional groups 10) Urethane acrylate B 10 parts (Shin Nakamura Chemical Industry Co., Ltd., product name: U-15HA: molecular weight 2,300, number of functional groups 15) Pentaerythritol triacrylate 60 parts (Toagosei, product name: M-305) Silica particles 20 parts (Surface-treated amorphous silica, d50: 3.5 μm) ·Organic particles A 8 parts (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.515) ·Organic particles B 2 parts (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.595) Photopolymerization initiator 5.0 parts (IGM Resins BV, product name: Omnirad184) Photopolymerization initiator 1.0 parts (IGM Resins BV, product name: Omnirad907) Silicone leveling agent 0.1 parts (Momentive Performance Materials, product name: TSF4460) Solvent (toluene) 200 parts Solvent (cyclohexanone) 5 parts Solvent (methyl isobutyl ketone) 10 parts

[0172] <Anti-glare layer coating solution 5> Urethane acrylate A 30 parts (Mitsubishi Chemical Corporation, product name: U-1700B: molecular weight 2,000, number of functional groups 10) Urethane acrylate B 10 parts (Shin Nakamura Chemical Industry Co., Ltd., product name: U-15HA: molecular weight 2,300, number of functional groups 15) Pentaerythritol triacrylate 60 parts (Toagosei, product name: M-305) Silica particles 10 parts (Surface-treated amorphous silica, d10: 0.08, d50: 2.8 μm, d90: 4.5 μm) ·Organic particles A 5 parts (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.515) ·Organic particles B 5 parts (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.595) Photopolymerization initiator 5.0 parts (IGM Resins BV, product name: Omnirad184) Photopolymerization initiator 1.0 parts (IGM Resins BV, product name: Omnirad907) Silicone leveling agent 0.1 parts (Momentive Performance Materials, product name: TSF4460) Solvent (toluene) 180 parts Solvent (cyclohexanone) 30 parts Solvent (methyl isobutyl ketone) 5 parts

[0173] <Anti-glare layer coating solution 6> Urethane acrylate C 60 parts (Shin Nakamura Chemical Industry Co., Ltd., product name: U-1100H: molecular weight 800, number of functional groups 6) Pentaerythritol triacrylate 40 parts (Toagosei, product name: M-305) ·Organic particles C 11 parts (Spherical polyacrylic-styrene copolymer, average particle size 3.0 μm, refractive index 1.595) ·70 parts of inorganic ultrafine particles (Silica with reactive functional groups introduced on the surface, solvent: MIBK, solid content: 30%) (Average primary particle diameter 12nm) Photopolymerization initiator 5.0 parts (IGM Resins BV, product name: Omnirad184) Photopolymerization initiator 1.0 parts (IGM Resins BV, product name: Omnirad907) Silicone leveling agent 0.1 parts (Momentive Performance Materials, product name: TSF4460) Solvent (toluene) 180 parts Solvent (cyclohexanone) 15 parts

[0174] <Anti-glare layer coating solution 7> Urethane acrylate A 30 parts (Mitsubishi Chemical Corporation, product name: U-1700B: molecular weight 2,000, number of functional groups 10) Urethane acrylate B 10 parts (Shin Nakamura Chemical Industry Co., Ltd., product name: U-15HA: molecular weight 2,300, number of functional groups 15) Pentaerythritol triacrylate 60 parts (Toagosei, product name: M-305) Silica particles 3 parts (Surface-treated amorphous silica, d10: 0.08, d50: 2.8 μm, d90: 4.5 μm) ·Organic particles B 0.5 part (Spherical polyacrylic-styrene copolymer, average particle size 1.5 μm, refractive index 1.595) Photopolymerization initiator 5.0 parts (IGM Resins BV, product name: Omnirad184) Photopolymerization initiator 1.0 parts (IGM Resins BV, product name: Omnirad907) Silicone leveling agent 0.1 parts (Momentive Performance Materials, product name: TSF4460) Solvent (toluene) 180 parts Solvent (cyclohexanone) 5 parts Solvent (methyl isobutyl ketone) 25 parts

[0175] <Low refractive index layer coating solution 2> Multifunctional acrylate 180 parts (Manufactured by Toagosei Co., Ltd., product name "Aronix M-400") Hollow silica particles 100 parts (Average primary particle diameter: 75 nm, particles surface-treated with a silane coupling agent having a methacryloyl group) Fluorine-based silicone leveling agent with reactive functional groups 600 parts (Shin-Etsu Chemical Co., Ltd., product name "KY1203", solid content: 20%, solvent: methyl isobutyl ketone) Photopolymerization initiator 5 parts (IGM Resins, product name "Omnirad127") Solvent (methyl isobutyl ketone) 11,000 parts Solvent (1-methoxy-2-propyl acetate) 1,300 parts

[0176] <Low refractive index layer coating solution 3> Multifunctional acrylate 100 parts (Manufactured by Toagosei Co., Ltd., product name "Aronix M-400") Acrylic polymer 0.5 parts (weight average molecular weight: 40,000) Hollow silica particles 100 parts (Average primary particle diameter: 75 nm, particles surface-treated with a silane coupling agent having a methacryloyl group) Fluorine-based silicone leveling agent with reactive functional groups: 250 parts (Shin-Etsu Chemical Co., Ltd., product name "KY1203", solid content: 20%, solvent: methyl isobutyl ketone) Photoinitiator 5 parts (IGM Resins, product name “Omnirad127”) Solvent (methyl isobutyl ketone) 11,000 parts Solvent (1-methoxy-2-propyl acetate) 1,300 parts

[0177] <Low refractive index layer coating solution 4> Multifunctional acrylate 100 parts (Manufactured by Toagosei Co., Ltd., product name "Aronix M-400") Acrylic polymer 0.5 parts (weight average molecular weight: 40,000) Hollow silica particles 180 parts (Average primary particle diameter: 75 nm, particles surface-treated with a silane coupling agent having a methacryloyl group) Fluorine-based silicone leveling agent with reactive functional groups 150 parts (Shin-Etsu Chemical Co., Ltd., product name "KY1203", solid content: 20%, solvent: methyl isobutyl ketone) Photopolymerization initiator 5.0 parts (IGM Resins, product name "Omnirad127") Solvent (methyl isobutyl ketone) 11,000 parts Solvent (1-methoxy-2-propyl acetate) 1,300 parts

[0178] [Table 1]

[0179] [Table 2]

[0180] From the results in Table 1, it can be seen that the optical films of the examples can provide good anti-glare properties and ease of wiping off fingerprints. [Explanation of symbols]

[0181] 10: Base material 20: Anti-glare layer 30: Anti-reflection layer 100: Optical film 110: Display element 120: Image display panel

Claims

1. An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, the first surface has an uneven shape, The first surface has a valley volume Vvv of 0.005 ml / m as defined in ISO 25178-2:2012. ２ That's all, Regarding the transmitted image clarity measured in accordance with JIS K7374:2007, when the transmitted image clarity when the optical comb width is 0.125 mm is defined as C0.125, the transmitted image clarity when the optical comb width is 0.25 mm is defined as C0.25, the transmitted image clarity when the optical comb width is 0.5 mm is defined as C0.5, the transmitted image clarity when the optical comb width is 1.0 mm is defined as C1.0, and the transmitted image clarity when the optical comb width is 2.0 mm is defined as C2.0, C0.125 is 1.0% or more and 30% or less, C0.25 is 1.0% or more and 30% or less, C0.5 is 1.0% or more and 30% or less, C1.0 is 1.0% or more and 30% or less, and C2.0 is 5.0% or more and 30% or less, An optical film having a drop contact angle of 30.0 degrees or more as measured by the following method. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped onto the first surface of the optical film from a height of 45 mm. The droplet is dropped perpendicular to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method.

2. An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, the first surface has an uneven shape, the first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2 or more; With regard to the transmitted image clarity measured in accordance with JIS K7374:2007, when the transmitted image clarity when the optical comb width is 0.125 mm is defined as C0.125, the transmitted image clarity when the optical comb width is 0.5 mm is defined as C0.5, the transmitted image clarity when the optical comb width is 1.0 mm is defined as C1.0, and the transmitted image clarity when the optical comb width is 2.0 mm is defined as C2.0, the sum of C0.125, C0.5, C1.0, and C2.0 is 10.0% or more and 80% or less, An optical film having a drop contact angle of 30.0 degrees or more as measured by the following method. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped onto the first surface of the optical film from a height of 45 mm. The droplet is dropped perpendicular to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method.

3. An optical film as described in claim 1 or 2, wherein the ratio (Vvv / Vvc) of Vvv to Vvc, the core spatial volume defined in ISO 25178-2:2012, of the first surface is 0.10 or less.

4. The optical film described in claim 1 or 2, wherein the first surface has a minimum autocorrelation length Sal defined in ISO 25178-2:2012 of 4.0 μm or more and 12.0 μm or less.

5. An optical film as described in claim 1 or 2, wherein the first surface has a polar height Sxp, which is defined in ISO 25178-2:2012 and means the difference between the height at a load area ratio of 2.5% and the height at a load area ratio of 50%, of 0.15 μm or more and 2.00 μm or less.

6. An optical film as described in claim 1 or 2, which has, from the first surface to the second surface, the anti-reflection layer, the anti-glare layer, and a substrate in this order.

7. An optical film as described in claim 1 or 2, wherein the anti-glare layer comprises a binder resin and particles.

8. An optical film described in claim 1 or 2, wherein the elemental ratios obtained by analyzing the surface region on the first side by X-ray photoelectron spectroscopy satisfy the following formulas 2 to 4. 3.5≦F / Inorganic Si≦10.0 (Formula 2) 0.08≦Organic Si / Inorganic Si≦1.00 (Formula 3) 5.0≦F / Organic Si≦50.0 (Formula 4) [In formulas 2 to 4, "F" is the ratio of fluorine element, "inorganic Si" is the ratio of silicon element belonging to the inorganic silicon compound, and "organic Si" is the ratio of silicon element belonging to the organic silicon compound.]

9. An optical film as described in claim 8, wherein the ratio of inorganic Si to all elements is 2 atomic % or more and 20 atomic % or less, with respect to the element ratio obtained by analysis by the X-ray photoelectron spectroscopy.

10. The optical film according to claim 1 or 2, wherein the total light reflectance R SCI of the optical film measured by the following method is 3.0% or less. [Measurement of total light reflectance (R SCI )] A sample is prepared by attaching a black plate to the second surface of the optical film via a transparent adhesive, and the total light reflectance (R SCI ) of the sample is measured with the optical film side as the light incident surface.

11. An optical film described in claim 1 or 2, having a haze according to JIS K7136:2000 of 20% or more and 75% or less.

12. A polarizing plate having a polarizer, a first transparent protective plate disposed on one side of the polarizer, and a second transparent protective plate disposed on the other side of the polarizer, A polarizing plate, wherein at least one of the first transparent protective plate and the second transparent protective plate is the optical film according to claim 1 or 2, and the second surface of the optical film is arranged opposite the polarizer.

13. A face panel for an image display device, in which a protective film is bonded to a resin plate or a glass plate, wherein the protective film is an optical film as described in claim 1 or 2, and the second surface of the optical film is arranged opposite the resin plate or the glass plate.

14. An image display panel having a display element and an optical film arranged on the light emission surface side of the display element, wherein the optical film includes the optical film described in claim 1 or 2.

15. An image display device comprising the image display panel described in claim 14.

16. A method for producing the optical film according to claim 1 or 2, comprising: A method for producing an optical film, comprising: a first step of forming an antiglare layer on a substrate; and a second step of forming an antireflection layer on the antiglare layer.

17. A method for selecting an optical film, comprising selecting an optical film that satisfies the following selection conditions: (Optical film selection criteria) An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, the first surface has an uneven shape, the first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2 or more; Regarding the transmitted image clarity measured in accordance with JIS K7374:2007, when the transmitted image clarity when the optical comb width is 0.125 mm is defined as C0.125, the transmitted image clarity when the optical comb width is 0.25 mm is defined as C0.25, the transmitted image clarity when the optical comb width is 0.5 mm is defined as C0.5, the transmitted image clarity when the optical comb width is 1.0 mm is defined as C1.0, and the transmitted image clarity when the optical comb width is 2.0 mm is defined as C2.0, C0.125 is 1.0% or more and 30% or less, C0.25 is 1.0% or more and 30% or less, C0.5 is 1.0% or more and 30% or less, C1.0 is 1.0% or more and 30% or less, and C2.0 is 5.0% or more and 30% or less, The drop contact angle measured by the following method is 30.0 degrees or more. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped onto the first surface of the optical film from a height of 45 mm. The droplet is dropped perpendicular to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method.

18. A method for selecting an optical film, comprising selecting an optical film that satisfies the following selection conditions: (Optical film selection criteria) An optical film having a first surface and a second surface opposite to the first surface, the optical film has an antireflection layer and an antiglare layer in this order from the first surface to the second surface, the first surface has an uneven shape, the first surface has a valley volume Vvv defined in ISO 25178-2:2012 of 0.005 ml / m 2 or more; With regard to the transmitted image clarity measured in accordance with JIS K7374:2007, when the transmitted image clarity when the optical comb width is 0.125 mm is defined as C0.125, the transmitted image clarity when the optical comb width is 0.5 mm is defined as C0.5, the transmitted image clarity when the optical comb width is 1.0 mm is defined as C1.0, and the transmitted image clarity when the optical comb width is 2.0 mm is defined as C2.0, the sum of C0.125, C0.5, C1.0, and C2.0 is 10.0% or more and 80% or less, The drop contact angle measured by the following method is 30.0 degrees or more. <Drop contact angle measurement> A droplet having a surface tension of 30 mN / m is dropped onto the first surface of the optical film from a height of 45 mm. The droplet is dropped perpendicular to the first surface. The static contact angle 10 seconds after the droplet hits the surface is measured by the θ / 2 method.

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