Anti-glare film; anti-glare article, touchscreen, and display device using same; and method for selecting anti-glare film

Patent metadata

Field	Value
Publication number	US-12130408-B2
Application number	US-202017615412-A
Country	US
Kind code	B2
Filing date	May 26, 2020
Priority date	Jun 7, 2019
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

Provided is an anti-glare film that can suppress glare in various display devices with different distances between the display elements and the anti-glare layer. The anti-glare film includes an anti-glare layer, wherein the anti-glare layer has a 500-μm square area, as measured for surface roughness, satisfying condition 1 and condition 2 below, where the maximum peak height is defined as P, a plane having a height obtained by adding P/6 to the average height is defined as the first reference plane, the number of projections exceeding the first reference plane is defined as N1, a plane having a height obtained by adding P/3 to the average height is defined as the second reference plane, and the number of projections exceeding the second reference plane is defined as N2:

P is 0.20 μm or more and 1.20 μm or less; and  <condition 1>

0.20≤ N 2/ N 1≤0.45.  <condition 2>.

First claim

The invention claimed is:

1. An anti-glare film comprising an anti-glare layer, wherein
the anti-glare layer has a 500-μm square area, as measured for surface roughness, satisfying condition 1 and condition 2 below, where the maximum peak height is defined as P, a plane having a height obtained by adding P/6 to the average height is defined as a first reference plane, the number of projections exceeding the first reference plane is defined as N1, a plane having a height obtained by adding P/3 to the average height is defined as a second reference plane, and the number of projections exceeding the second reference plane is defined as N2:
P is 0.20 μm or more and 1.20 μm or less; and  <condition 1>

0.20≤ N 2/ N 1≤0.45.  <condition 2>.

2. The anti-glare film according to claim 1 , wherein
the 500-μm square area satisfying condition 1 and condition 2 further satisfies condition 3 below, where a plane having a height obtained by adding P/2 to the average height is defined as a third reference plane, and the number of projections exceeding the third reference plane is defined as N3:
0.20≤ N 3/ N 2≤0.45.  <condition 3>

3. The anti-glare film according to claim 1 , wherein
the 500-μm square area satisfying condition 1 and condition 2 has a maximum height roughness PV of more than 0.60 μm and 1.50 μm or less.

4. The anti-glare film according to claim 1 , wherein
the 500-μm square area satisfying condition 1 and condition 2 has an arithmetic average roughness Sa of 0.020 μm or more and 0.070 μm or less.

5. The anti-glare film according to claim 1 , having an internal haze of 6.0% or less.

6. The anti-glare film according to claim 1 , wherein
the sum of clarities of transmitted images C 0.125 , C 0.25 , C 0.5 , C 1.0 and C 2.0 , as measured for each of optical combs having widths of 0.125 mm, 0.25 mm, 0.5 mm, 1.0 mm and 2.0 mm according to JIS K7374:2007, is 380% or more, where the clarity of the transmitted image of the optical comb having a width of 0.125 mm is defined as C 0.125 , the clarity of the transmitted image of the optical comb having a width of 0.25 mm is defined as C 0.25 , the clarity of the transmitted image of the optical comb having a width of 0.5 mm is defined as C 0.5 , the clarity of the transmitted image of the optical comb having a width of 1.0 mm is defined as C 1.0 , and the clarity of the transmitted image of the optical comb having a width of 2.0 mm is defined as C 2.0 .

7. An anti-glare article comprising the anti-glare film according to claim 1 arranged on a member such that the surface on the anti-glare layer side of the anti-glare film faces the front side of the anti-glare article.

8. A touchscreen comprising a transparent substrate on its front surface, wherein
the transparent substrate is the anti-glare film according to claim 1 arranged so that the surface on the anti-glare layer side of the anti-glare film faces a user's side.

9. A display device comprising:
a display element; and
an anti-glare film arranged on the light-emitting surface side of the display element, wherein
the anti-glare film is the anti-glare film according to claim 1 arranged so that the surface on the anti-glare layer side of the anti-glare film faces a direction opposite the display element.

10. A method for selecting an anti-glare film comprising an anti-glare layer, the method comprising:
determining, as a determination condition, whether or not the anti-glare layer has a 500-μm square area, as measured for surface roughness, satisfying condition 1 and condition 2 below, where the maximum peak height is defined as P, a plane having a height obtained by adding P/6 to the average height is defined as a first reference plane, the number of projections exceeding the first reference plane is defined as N1, a plane having a height obtained by adding P/3 to the average height is defined as a second reference plane, and the number of projections exceeding the second reference plane is defined as N2; and
selecting the anti-glare layer satisfying the determination condition:
P is 0.20 μm or more and 1.20 μm or less; and  <condition 1>

0.20≤ N 2/ N 1≤0.45.  <condition 2>.

Assignees

• Dainippon Printing Co Ltd

Inventors

• Sato Masaharu
• Fukuda Takayuki
• Furui Gen

Classifications

• G06F3/041

  Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means · CPC title

• G02F1/133502 Primary

  Antiglare, refractive index matching layers · CPC title

• G02B5/0221 Primary

  the surface having an irregular structure (G02B5/0226 takes precedence) · CPC title

• G02B1/111

  using layers comprising organic materials · CPC title

• G02B27/0012

  Optical design, e.g. procedures, algorithms, optimisation routines · CPC title