Antireflection laminate, polarizing plate and image display device

1. An antireflection laminate comprising the following layers in order:

a support;

a layer having hardcoat property;

an overcoat layer; and

a low refractive index layer,

wherein

the layer having hardcoat property comprises a metal oxide particle and an organic resin particle,

the organic resin particle has an average particle diameter of 0.5 to 8 μm,

the antireflection laminate has a surface haze value of 0 to 12%, an internal haze value of 0 to 60%, and a Sm value of 40 to 200 μm, wherein Sm is an average distance of irregularity shape,

the metal oxide particle is a cohesive metal oxide particle and has an average secondary particle diameter of 1 to 10 μm,

the average secondary particle diameter of the metal oxide particle is larger than an average particle diameter of the organic resin particle,

the difference between the average secondary particle diameter of the metal oxide particle and the average particle diameter of the organic resin particle is from 0.1 to 5 μm, and

the overcoat layer has a refractive index of 1.48 to 1.65 and satisfies the following formulae (I) and (II):

0.1 Rz ( HC )< t ( OC )<3 Rz ( HC )  (I)

wherein Rz(HC) represents a ten-point average roughness of the layer having hardcoat property and t(OC) represents a film thickness of the overcoat layer,

0.1 Rz ( HC )< Rz ( OC )<1 Rz ( HC )  (II)

wherein Rz(HC) represents a ten-point average roughness of the layer having hardcoat property and Rz(OC) represents a ten-point average roughness of the overcoat layer.

2. The antireflection laminate according to claim 1 , which has an integrated reflectance of 2.0% or less.

3. The antireflection laminate according to claim 1 , wherein the overcoat layer has a surface free energy of 20 to 45 mJ/m 2 .

4. The antireflection laminate according to claim 1 , wherein the low refractive index layer is formed by coating a low refractive index coating composition that comprises a heat-curable and/or ionizing radiation-curable resin component.

5. The antireflection laminate according to claim 4 , wherein the low refractive index coating composition comprises a fluorine-containing resin component.

6. The antireflection laminate according to claim 4 , wherein the low refractive index coating composition comprises a solvent having a boiling point of 120° C. or more in an amount of 3 to 50 mass % based on a total amount of the low refractive index coating composition.

7. The antireflection laminate according to claim 1 , wherein the low refractive index layer comprises an inorganic fine particle having an average particle diameter of 5 to 200 nm.

8. The antireflection laminate according to claim 7 , wherein the inorganic fine particle has, in at least either an inside or a surface thereof, a pore having an average pore diameter of 0.01 to 90 nm.

9. The antireflection laminate according to claim 1 , wherein the overcoat layer comprises at least one kind of a fluorine-based leveling agent and/or at least one kind of a silicone-based leveling agent.

10. The antireflection laminate according to claim 1 , wherein the overcoat layer is a layer formed by coating a overcoat layer coating composition that comprises:

a silane coupling agent represented by a following formula (a); and/or

a hydrolysate of the silane coupling agent and a condensation reaction product of the hydrolysate:

R a ) m —Si(X a ) 4-m   Formula (a)

wherein

each of X a ('s) independently represents a substituent that is selected from the group consisting of an unsubstituted alkyl group, a hydroxyl group and a hydrolyzable group,

each of R a ('s) independently represents a substituent that is selected from the group consisting of a halogen atom, a hydroxyl group, a mercapto group, a carboxyl group, an epoxy group, an alkenyl group, an acyloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, an acylamino group and an isocyanate group, and that may be further substituted, and

m represents an integer of 1 to 3.

11. A polarizing plate comprising:

a polarizing film; and

protective films provided on both sides of the polarizing film,

wherein at least one of the protective films is the antireflection laminate according to claim 1 .

12. An image display device comprising:

the polarizing plate according to claim 11 on a viewing side of a display screen of the image display device.

13. An image display device comprising:

the antireflection laminate according to claim 1 on a viewing side of a display screen of the image display device.