Anti-glare film and image display device

Patent metadata

Field	Value
Publication number	US-11960162-B2
Application number	US-202318350424-A
Country	US
Kind code	B2
Filing date	Jul 11, 2023
Priority date	May 15, 2020
Publication date	Apr 16, 2024
Grant date	Apr 16, 2024

Abstract

Provided is an anti-glare film excellent in anti-glare properties and capable of suppressing reflected scattered light. The anti-glare film includes an anti-glare layer, the anti-glare film having an uneven surface, wherein for an amplitude spectrum of elevation of the uneven surface, when a sum of amplitudes corresponding to spatial frequencies of 0.005 μm −1 , 0.010 μm −1 , and 0.015 μm −1 is defined as AM1 and an amplitude at a spatial frequency of 0.300 μm −1 is defined as AM2, AM1 is 0.070 μm or more and 0.400 μm or less, AM2 is 0.0050 μm or more, and AM2<AM1.

First claim

The invention claimed is:

1. An anti-glare film comprising an anti-glare layer, the anti-glare film having an uneven surface, wherein a smoothed reflected light intensity measured under the following measurement conditions satisfies the following conditions 1 and 2, wherein the uneven surface has a three-dimensional mean peak interval Smp of 2.524 μm or more and 8.228 μm or less,
<measurement conditions>
(1) in a transmission measurement mode of a goniophotometer, a visible light beam is emitted as a parallel light beam from a light source of the goniophotometer, an intensity of the emitted light is measured at an aperture angle of 1 degree without passing through a sample, and standardization is performed so that the maximum intensity is 100,000;
(2) a black plate is bonded to a surface opposite to the uneven surface of the anti-glare film via a transparent adhesive layer to produce a sample α in which the anti-glare film, the transparent adhesive layer, and the black plate are laminated and which has the uneven surface;
(3) the sample α is placed in the goniophotometer, the uneven surface of the sample α is irradiated with a visible light beam as a parallel light beam from the light source of the goniophotometer, and a reflected light intensity is measured at an aperture angle of 1 degree, wherein an irradiation angle of the parallel light beam is set to a direction inclined by +45 degrees from a normal direction of the sample α, the reflected light intensity is measured at intervals of 1 degree from 0 degrees, which is the normal direction of the sample α, to −85 degrees, and in order to maintain effects of standardization in (1), the reflected light intensity is measured in the transmission measurement mode; and
(4) a smoothing process represented by the following formula (i) is performed at each angle from 0 degrees to −85 degrees, and the reflected light intensity after the smoothing process is defined as the smoothed reflected light intensity at each angle:
n −degree smoothed reflected light intensity=([ n− 2-degree reflected light intensity]+[ n− 1-degree reflected light intensity]+[ n −degree reflected light intensity]+[ n+ 1-degree reflected light intensity]+[ n+ 2-degree reflected light intensity])/5  (i)

<condition 1>
when the n-degree smoothed reflected light intensity is defined as Rn, and the n−1-degree smoothed reflected light intensity is defined as Rn−1, a maximum absolute value of difference between Rn and Rn−1 is 2.00 or less, and

<condition 2>
the smoothed reflected light intensity at −35 degrees is 0.1 or more and 4.0 or less.

2. The anti-glare film according to claim 1 , wherein in Condition 1, the maximum absolute value of difference is 1.00 or less.

3. The anti-glare film according to claim 1 , further satisfying the following condition 3:
<condition 3>
the smoothed reflected light intensity at −45 degrees is 8.0 or less.

4. The anti-glare film according to claim 1 , having a haze of 60% or more and 98% or less according to JIS K7136:2000.

5. The anti-glare film according to claim 1 , wherein the anti-glare layer contains a binder resin and particles.

6. The anti-glare film according to claim 5 , wherein when a thickness of the anti-glare layer is defined as T and an average particle size of the particles is defined as D, D/T is 0.20 or more and 0.96 or less.

7. The anti-glare film according to claim 5 , wherein the particles have an average particle size D of 1.0 μm or more and 5.0 μm or less.

8. The anti-glare film according to claim 5 , wherein the particles are contained in an amount of 40 parts by mass or more and 200 parts by mass or less based on 100 parts by mass of the binder resin.

9. The anti-glare film according to claim 5 , wherein the particles are organic particles.

10. The anti-glare film according to claim 5 , wherein the anti-glare layer further contains inorganic fine particles.

11. The anti-glare film according to claim 10 , wherein the inorganic fine particles are contained in an amount of 40 parts by mass or more and 200 parts by mass or less based on 100 parts by mass of the binder resin.

12. The anti-glare film according to claim 5 , wherein the binder resin comprises a cured product of an ionizing radiation-curable resin composition and a thermoplastic resin.

13. The anti-glare film according to claim 1 , further comprising an anti-reflection layer on the anti-glare layer, a surface of the anti-reflection layer being the uneven surface.

14. An image display device comprising:
a display element; and
the anti-glare film according to claim 1 disposed on the display element so that a surface of the anti-glare film on the uneven surface side is disposed so as to face the opposite side to the display element, the anti-glare film being disposed on an outermost surface.

Assignees

• Dainippon Printing Co Ltd

Inventors

• Kuzuhara Mitsuhiro
• Iwata Yukimitsu
• Tsujimoto Jun
• Murakami Shigeki
• Furui Gen

Classifications

• G02B1/118 Primary

  having sub-optical wavelength surface structures designed to provide an enhanced transmittance, e.g. moth-eye structures · CPC title

• H10K59/8791

  Arrangements for improving contrast, e.g. preventing reflection of ambient light · CPC title

• G01J1/0242

  Control or determination of height or angle information of sensors or receivers; Goniophotometry · CPC title

• G02F1/133314

  Back frames · CPC title

• G02F1/133331

  Cover glasses · CPC title