Laminated optical film, method of producing laminated optical film, optical element, and image display

Patent metadata

Field	Value
Publication number	US-11536877-B2
Application number	US-201615754406-A
Country	US
Kind code	B2
Filing date	Jul 29, 2016
Priority date	Aug 24, 2015
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

The present invention is intended to provide a laminated optical film achieving both a high proportion of void space (porosity) and superior abrasion resistance. The laminated optical film of the present invention includes: a void-provided layer; a resin film; and a cover layer, wherein the void-provided layer is formed on the resin film, the cover layer is formed directly on the void-provided layer, and the void-provided layer has a contact angle with water of 90° or more and a proportion of void space of 30 vol % or more.

First claim

The invention claimed is:

1. A laminated optical film comprising:
a void-provided layer;
a resin film; and
a cover layer, wherein:
the void-provided layer is formed on the resin film,
the cover layer having a thickness of from 50 to 10,000 nm is formed directly on the void-provided layer,
the void-provided layer has a contact angle with water of 90° or more, and a proportion of void spaces of 30 vol % or more such that the void spaces of the void-provided layer are not filled with the cover layer,
the void-provided layer is a porous body in which microporous particles are chemically bonded to each other,
the cover layer is porous with a proportion of void spaces of 10 vol % or less,
the cover layer contains a water-soluble polymer, and a water-soluble silane crosslinked product formed from at least one of monomers and oligomers of water-soluble alkoxysilane, said monomers and/or oligomers of water-soluble alkoxysilane of the cover layer chemically bonded to the microporous particles of the void-provided layer, and
after the steel wool test on the cover layer (φ25 mm, 100 g (load)×10 (reciprocation)), no scratch was found by visual observation.

2. The laminated optical film according to claim 1 , wherein the cover layer is a layer having an abrasion resistance.

3. The laminated optical film according to claim 1 , wherein the void-provided layer has a refractive index of 1.3 or less.

4. The laminated optical film according to claim 1 , wherein the void-provided layer further includes structural units selected from the group consisting of a particle, a fiber, a plate, and any combinations thereof, wherein the structural units are chemically bonded directly or indirectly with minute void spaces formed between adjacent structural units, and wherein the void-provided layer contains a crosslinking assisting agent for indirectly bonding the structural units.

5. The laminated optical film according to claim 4 , wherein a content of the crosslinking assisting agent in the void-provided layer relative to a weight of the structural unit is in a range from 0.01 wt % to 20 wt %.

6. An optical element comprising: the laminated optical film according to claim 1 .

7. An image display comprising: the optical element according to claim 6 .

8. The laminated optical film according to claim 1 , wherein the microporous particles are chemically bonded to each other by a catalysis of a catalyst.

9. The laminated optical film according to claim 8 , wherein the microporous particle includes a pulverized product of a gelled silica compound.

10. The laminated optical film according to claim 1 , wherein the microporous particle includes a pulverized product of a gelled silica compound.

11. The laminated optical film according to claim 1 , wherein the cover layer has a proportion of void spaces of 9 vol % or less.

12. The laminated optical film according to claim 1 , wherein the cover layer has a proportion of void spaces of 8 vol % or less.

Assignees

• Nitto Denko Corp

Inventors

• Hattori Daisuke
• Nakamura Kozo
• Hosokawa Kazuhito

Classifications

• B32B2305/026

  Porous · CPC title

• B32B2307/73

  Hydrophobic · CPC title

• C08J2367/02

  Polyesters derived from dicarboxylic acids and dihydroxy compounds; (C08J2367/06 takes precedence) · CPC title

• G02B1/14 Primary

  Protective coatings, e.g. hard coatings · CPC title

• C08J2429/04

  Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids · CPC title