Hard Coat Layer Composition and Hard Coat Film

• US 20090274902A1
• Filed: 04/28/2009
• Published: 11/05/2009
• Est. Priority Date: 04/30/2008
• Status: Abandoned Application

• Current Assignee: Toppan Printing Co., Ltd. (TOPPAN Holdings, Inc.)
• Original Assignee: Toppan Printing Co., Ltd. (TOPPAN Holdings, Inc.)
• Inventors: Kume, Makoto
• Application Number:
  US12/431,703
• Publication Number:
  US 20090274902A1
• Time in Patent Office: Days
• US Class Current: 428/336
• CPC Class Codes: C08F 222/1065 of alcohol terminated (poly)urethanes, e.g. urethane(meth)acrylates
• CPC Class Codes: C09D 4/00 Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16
• CPC Class Codes: G02B 1/105 Protective coatings
• CPC Class Codes: G02B 1/14 Protective coatings, e.g. hard coatings
• CPC Class Codes: G02B 1/18 Coatings for keeping optical surfaces clean, e.g. hydrophobic or photo-catalytic films G02B1/16 takes precedence
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

The present invention provides a hard coat film and a hard coat layer forming composition which forms a hard coat layer adhering well to a substrate, which does not curl up easily and having antifouling properties, excellent abrasion resistance, surface hardness, and a high level of visibility. The present invention has a specific feature in that a hard coat layer forming composition which includes polyfunctional acrylic (or methacrylic) monomer (A), acrylic monomer having a hydroxyl group (B), radical photopolymerization initiator (C), and fluorocompound having a polymerizable group (D) is used. The hard coat film of the present invention has the hard coat layer which is formed by curing the hard coat layer forming composition on a transparent substrate and has a surface free energy less than 20 mN/m and the thickness in the range of 5-25 μm.

Claims

1. A hard coat layer forming composition comprising:

a polyfunctional acrylic or methacrylic monomer (A);

an acrylic or methacrylic monomer having a hydroxyl group (B);

a radical photopolymerization initiator (C); and

a fluorocompound having a polymerizable group (D).

2. The hard coat layer forming composition in accordance with claim 1, wherein a major component of said polyfunctional acrylic or methacrylic monomer (A) is a urethane acrylate or methacrylate monomer and/or a urethane acrylate or methacrylate oligomer.

3. The hard coat layer forming composition in accordance with claim 1, wherein said polyfunctional acrylic or methacrylic monomer (A) is contained in the range of 50-95% by weight relative to a sum of said polyfunctional acrylic or methacrylic monomer (A) and said acrylic or methacrylic monomer having a hydroxyl group (B).

4. The hard coat layer forming composition in accordance with claim 1, wherein said fluorocompound having a polymerizable group (D) is added in the range of 0.01-10% by weight relative to a sum of said polyfunctional acrylic or methacrylic monomer (A) and said acrylic or methacrylic monomer having a hydroxyl group (B).

5. The hard coat layer forming composition in accordance with claim 1, wherein said radical photopolymerization initiator (C) is added in the range of 0.01-10% by weight relative to a sum of said polyfunctional acrylic or methacrylic monomer (A) and said acrylic or methacrylic monomer having a hydroxyl group (B).

6. A hard coat film comprising a hard coat layer which is formed on a transparent substrate by curing said hard coat layer forming composition in accordance with claim 1, wherein

a surface free energy of said hard coat layer is less than or equal to 20 mN/m and the thickness of said hard coat layer is in the range of 5-25 μ

m.

7. The hard coat film in accordance with claim 6, wherein said surface free energy of said hard coat layer is more than or equal to 15 mN/m.

8. The hard coat film in accordance with claim 6, wherein said transparent substrate is mainly made of triacetyl cellulose.

9. The hard coat film in accordance with claim 6, wherein the light transmittance of said hard coat film is in the range of 90-97%.

10. The hard coat film in accordance with claim 6, wherein a haze of said hard coat film is in the range of 0.1-1.0%.

11. The hard coat film in accordance with claim 6, wherein a pencil hardness of said hard coat film is higher than or equal to 3H.

12. A polarizing plate comprising said hard coat film in accordance with claim 6, wherein

said transparent substrate has a polarizing layer and another transparent substrate on the opposite side from said hard coat layer.

13. A transmission type LCD comprising:

said polarizing plate in accordance with claim 12;

a liquid crystal cell;

a polarizing plate; and

a back light unit, in the order of this description.