Anti-glare film, manufacturing method for same, polarizing plate and image display device

• US 9,164,203 B2
• Filed: 03/17/2011
• Issued: 10/20/2015
• Est. Priority Date: 03/18/2010
• Status: Active Grant

• Current Assignee: Dai Nippon Printing Company Limited
• Original Assignee: Dai Nippon Printing Company Limited
• Inventors: Kodama, Takashi, Honda, Makoto, Suzuki, Hiroko
• Primary Examiner(s): Shafer, Ricky D
• Application Number:
  US13/635,604
• Publication Number:
  US 20130057955A1
• Time in Patent Office: 1,678 Days
• Field of Search: 359/487.01, 359/599, 359/601, 359/900, 359/488.01, 349/96, 349/112, 349/137, 427/508, 427/162, 427/163.1, 427/164
• US Class Current: 1/1
• CPC Class Codes: G02B 1/111 using layers comprising organic materials
• CPC Class Codes: G02B 5/02 Diffusing elements; Afocal elements
• CPC Class Codes: G02B 5/0221 the surface having an irregular structure G02B5/0226 takes precedence
• CPC Class Codes: G02B 5/0242 by means of dispersed particles
• CPC Class Codes: G02B 5/0268 characterized by the fabrication or manufacturing method
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00
• CPC Class Codes: G02F 1/133502 Antiglare, refractive index matching layers
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606
• CPC Class Codes: G02F 1/133528 Polarisers

Abstract

Provided is an anti-glare film having excellent anti-glare property, and suppressing white muddiness and scintillation, generation of cracks when attaching the films to polarizing elements and a fabrication process of liquid crystal cells, and changes of an anti-glare property over time. An anti-glare film comprises a light-transmitting substrate; and a diffusion layer having a surface roughness and provided on at least one surface of the light-transmitting substrate, in which the diffusion layer is obtainable by applying, on the at least one surface of the light-transmitting substrate, a coating composition including organic fine particles and a radiation curable binder that includes a (meth)acrylate monomer as an essential component, drying the composition to form a coating, and curing it, the organic fine particles in the diffusion layer have an impregnation layer being impregnated with the radiation curable binder, and the impregnation layer has an average thickness of 0.01 to 1.0 μm.

Claims

1. An anti-glare film, comprising:

a light-transmitting substrate; and

a diffusion layer having a surface roughness and provided on at least one surface of the light-transmitting substrate,

wherein the diffusion layer is obtainable by applying, on the at least one surface of the light-transmitting substrate, a coating composition including organic fine particles (A) and a radiation curable binder that includes a (meth)acrylate monomer as an essential component, drying the coating composition to form a coating, and curing the coating,

the organic fine particles (A) in the diffusion layer each have an impregnation layer that is impregnated with the radiation curable binder, and

the impregnation layer has an average thickness of 0.01 to 1.0 μ

m.

2. The anti-glare film according to claim 1,

wherein a haze variation during a 60°

C., 90% RH, 1000-hour moisture and heat resistance test is 1.5% or less.

3. The anti-glare film according to claim 2,

wherein the diffusion layer further includes fine particles (B) with an average particle size of smaller than an average particle size of the organic fine particles (A).

4. The anti-glare film according to claim 2

wherein the coating composition includes at least a solvent that swells the organic fine particles (A).

5. The anti-glare film according to claim 1,

wherein the diffusion layer further includes fine particles (B) with an average particle size of smaller than an average particle size of the organic fine particles (A).

6. The anti-glare film according to claim 5,

wherein Δ

_A and Δ

_B satisfy the formula (1);

|Δ

_A|<

|A_B| 

 

(1)

wherein Δ

_A represents a difference between a refractive index of the radiation curable binder and a refractive index of the organic fine particles (A) and Δ

_B represents a difference between a refractive index of the radiation curable binder and a refractive index of the fine particles (B).

7. The anti-glare film according to claim 6,

wherein D_A1 and D_A2 satisfy the formula (2):

0.01 μ

m<

D_A2−

D_A1<

1.0 μ

m 

 

(2)

wherein D_A1 represents an average particle size of the organic fine particles (A) and D_A2 represents an average particle size of the organic fine particles (A) in the diffusion layer.

8. The anti-glare film according to claim 5,

wherein D_A1 and D_A2 satisfy the formula (2):

0.01 μ

m<

D_A2−

D_A1<

1.0 μ

m 

 

(2)

wherein D_A1 represents an average particle size of the organic fine particles (A) and D_A2 represents an average particle size of the organic fine particles (A) in the diffusion layer.

9. The anti-glare film according to claim 5,

wherein D_A1, D_B1, D_A2, and D_B2 satisfy the formula (3):

1.0 μ

m>

D_A2−

D_A1>

D_B2−

D_B1≧

0 

 

(3)

wherein D_A1 represents an average particle size of the organic fine particles (A), D_B1 represents an average particle size of the fine particles (B), D_A2 represents an average particle size of the organic fine particles (A) in the diffusion layer, and D_B2 represents an average particle size of the fine particles (B) in the diffusion layer.

10. The anti-glare film according to claim 5,

wherein the fine particles (B) are organic fine particles.

11. The anti-glare film according to claim 5

wherein the coating composition includes at least a solvent that swells the organic fine particles (A).

12. The anti-glare film according to claim 1,

wherein the coating composition includes at least a solvent that swells the organic fine particles (A).

13. The anti-glare film according to claim 12,

wherein Δ

_A and Δ

_B satisfy the formula (1);

|Δ

_A|<

|A_B| 

 

(1)

wherein Δ

_A represents a difference between a refractive index of the radiation curable binder and a refractive index of the organic fine particles (A) and Δ

_B represents a difference between a refractive index of the radiation curable binder and a refractive index of the fine particles (B).

14. The anti-glare film according to claim 12,

wherein D_A1 and D_A2 satisfy the formula (2):

0.01 μ

m<

D_A2−

D_A1<

1.0 μ

m 

 

(2)

wherein D_A1 represents an average particle size of the organic fine particles (A) and D_A2 represents an average particle size of the organic fine particles (A) in the diffusion layer.

15. The anti-glare film according to claim 1,

wherein the diffusion layer further includes a lamellar inorganic compound.

16. The anti-glare film according to claim 15,

wherein the lamellar inorganic compound is talc.

17. A polarizer provided with a polarizing element, the polarizer comprising the anti-glare film according to claim 1, provided on a surface of the polarizing element.

18. An image display device, comprising the anti-glare film according to claim 1, or the polarizer according to claim 17 on an outermost surface of the image display device.

19. A method for producing an anti-glare film that includes a light-transmitting substrate and a diffusion layer having a surface roughness and provided on least one surface of the light-transmitting substrate,

the method comprising forming the diffusion layer by applying, on the at least one surface of the light-transmitting substrate, a coating composition including organic fine particles (A), a radiation curable binder that includes a (meth)acrylate monomer as an essential component, and a solvent;

drying the coating composition to form a coating; and

curing the coating,

the radiation curable binder or the solvent or both including a component that swells the organic fine particles (A),

the organic fine particles (A) each having an impregnation layer that is impregnated with the radiation curable binder and has an average thickness of 0.01 to 1.0 μ

m.