Hard coating film and image display device comprising same

Patent metadata

Field	Value
Publication number	US-11958953-B2
Application number	US-201917059258-A
Country	US
Kind code	B2
Filing date	May 27, 2019
Priority date	Jun 8, 2018
Publication date	Apr 16, 2024
Grant date	Apr 16, 2024

Abstract

A hard coating film may include a substrate and a hard coating layer provided on at least one surface of the substrate, in which, when the hard coating film is folded and unfolded 200,000 times with a bending radius of 1 mm in the direction in which the hard coating layer is oriented inwards under 60° C. and 90% relative humidity (RH), breakage does not occur, and the amount of change in transmission b* (chromaticity) of the film after UV irradiation for 100 hr using a 15 W UV-B lamp is 1.5 or less. The hard coating film may exhibit superior anti-curling properties, superior bending resistance under high-temperature and high-humidity conditions, and high light resistance, and can thus be applied not only to an image display device but also to a window for a flexible display device.

First claim

The invention claimed is:

1. A hard coating film, comprising:
a substrate; and
a hard coating layer provided on at least one surface of the substrate, wherein the hard coating layer comprises a cured product of a hard coating composition comprising a first photopolymerization initiator having a maximum absorption wavelength of 250 nm or less and a second photopolymerization initiator having a maximum absorption wavelength of 300 nm or less but exceeding 250 nm, and
wherein, when the hard coating film is folded and unfolded 200,000 times with a bending radius of 1 mm in a direction in which the hard coating layer is oriented inwards under 60° C. and 90% relative humidity (RH), breakage does not occur, and an amount of change in transmission b* (chromaticity) of the film after UV irradiation for 100 hr using a 15 W UV-B lamp is 1.5 or less.

2. The hard coating film of claim 1 , wherein the hard coating composition further comprises at least one selected from the group consisting of a light-transmissive resin, a solvent, and an additive.

3. The hard coating film of claim 2 , wherein the light-transmissive resin comprises dendritic acrylate.

4. The hard coating film of claim 1 , wherein an amount of each of the first photopolymerization initiator and the second photopolymerization initiator is 0.1 to 10 parts by weight based on a total of 100 parts by weight of the hard coating composition.

5. An image display device comprising the hard coating film of claim 1 .

6. A window for a flexible display device comprising the hard coating film of claim 1 .

Assignees

• Dongwoo Fine Chem Co Ltd

Inventors

• Lim Geo San
• Kim Seung Hee
• Kim Hye Lin

Classifications

• C08J7/046 Primary

  Forming abrasion-resistant coatings; Forming surface-hardening coatings · CPC title

• C08K11/00

  Use of ingredients of unknown constitution, e.g. undefined reaction products · CPC title

• C09D133/08

  Homopolymers or copolymers of acrylic acid esters · CPC title

• G02B1/14 Primary

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

• C08J2335/08

  Copolymers with vinyl ethers · CPC title