Optical adhesive sheet

Patent metadata

Field	Value
Publication number	US-11745462-B2
Application number	US-201615545756-A
Country	US
Kind code	B2
Filing date	Mar 9, 2016
Priority date	Jun 22, 2015
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

An optical adhesive sheet having an excellent repulsion resistance and an excellent swelling rate, and a method for manufacturing the same.

First claim

The invention claimed is:

1. An optical adhesive sheet, comprising:
a polyethylene foam substrate; and
an adhesive agent layer formed on at least one surface of the substrate, wherein the adhesive agent layer has micro pores capable of being impregnated with a solvent, wherein the adhesive agent layer is formed by curing an adhesive agent composition, which comprises an acrylic copolymer formed by polymerizing a monomer mixture consisting of ethylhexyl acrylate, isobornyl acrylate, and acrylic acid, and
a swelling rate of the adhesive agent layer, which is calculated by the following Equation 1, is from 60% to 90%:
Swelling rate (%)=( W 2 /W 1 )×100   [Equation 1]

where,
W 1 =an initial weight which is a weight of a sample before immersing the sample, which is obtained by cutting a cured adhesive agent layer into a predetermined size, into a solvent, and
W 2 =a post weight which is a weight of a sample obtained by immersing the sample into the solvent, wherein the solvent is chloroform, ethyl acetate, acetone, methanol, ethanol, isopropanol, butanol or dimethylformamide, leaving the sample to stand for a predetermined time, filtering the sample using a filtration device at a temperature from 100° C. to 150° , wherein the filtration device is a 300 mesh steel screen, and then drying the sample.

2. The adhesive sheet of claim 1 , wherein the adhesive agent composition further comprises a photoinitiator selected from the group consisting of a benzoin-based initiator, a hydroxy ketone-based initiator, an amino ketone-based initiator, caprolactam, and a combination thereof.

3. The optical adhesive sheet of claim 1 , wherein the acrylic copolymer is formed by polymerizing the monomer mixture at an ambient temperature of 20 to 30° C. by irradiation with UV light having a UV intensity of 6 to 8 mW/cm 2 .

4. The optical adhesive sheet of claim 3 , wherein a total UV dose irradiated onto the adhesive agent composition at an ambient temperature of 20 to 30° C. is 1,575 mJ/cm 2 to 1,750 mJ/cm 2 .

5. A method for manufacturing an optical adhesive sheet of claim 1 , the method comprising:
forming an adhesive agent composition comprising an acrylic copolymer formed by polymerizing a monomer mixture consisting of ethylhexyl acrylate, isobornyl acrylate and acrylic acid; and
forming an adhesive agent layer by applying the adhesive agent composition onto at least one surface of a polyethylene foam substrate and UV-curing the adhesive agent composition,
wherein the UV-curing is carried out by using UV light having a UV intensity of 6 to 8 mW/cm 2 at an ambient temperature of 20 to 30° C., and
a swelling rate of the adhesive agent layer, which is calculated by the following Equation 1, is from 60% to 90%:
Swelling rate (%)=( W 2 /W 1 )×100   [Equation 1]

where,
W 1 =an initial weight which is a weight of a sample before immersing the sample, which is obtained by cutting a cured adhesive agent layer into a predetermined size, into a solvent, and
W 2 =a post weight which is a weight of a sample obtained by immersing the sample into the solvent, leaving the sample to stand for a predetermined time, filtering the sample using a filtration device, and then drying the sample, and
wherein a total UV dose irradiated onto the adhesive agent composition at the ambient temperature is 1,575 mJ/cm 2 to 1,750 mJ/cm 2 .

6. The method of claim 5 , wherein the adhesive agent composition further comprises a photoinitiator selected from the group consisting of a benzoin-based initiator, a hydroxy ketone-based initiator, an amino ketone-based initiator, caprolactam, and a combination thereof.

Assignees

• Lg Chemical Ltd

Inventors

• Jang Ae-Jung
• Choi Hong-June
• Kim Jang-Soon

Classifications

• B32B5/18 Primary

  characterised by features of a layer {of} foamed material · CPC title

• B32B5/22

  characterised by the presence of two or more layers which {are next to each other and are fibrous, filamentary, formed of particles or foamed (layer formed of natural mineral fibres or particles next to a foam layer B32B19/047, next to a layer made of particles B32B19/048, or next to a fibrous or filamentary layer B32B19/06; paper layer or cardboard layer next to a paper layer or cardboard layer B32B29/005, next to a foam layer B32B29/007, next to a fibrous or filamentary layer B32B29/02, or next to a particulate layer B32B29/04)} · CPC title

• B32B7/12

  using interposed adhesives or interposed materials with bonding properties · CPC title

• B32B15/046

  of foam · CPC title

• B32B15/09

  comprising polyesters · CPC title