Adhesive composition and display device

Patent metadata

Field	Value
Publication number	US-2016145472-A1
Application number	US-201514884589-A
Country	US
Kind code	A1
Filing date	Oct 15, 2015
Priority date	Nov 24, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

Disclosed are an adhesive composition that includes: a first photopolymerization initiator having a maximum absorption wavelength in a range of about 350 nm to about 370 nm and a second photopolymerization initiator having a maximum absorption wavelength in a range of about 380 nm to about 390 nm, and a method of manufacturing a display device.

First claim

What is claimed is:

1 . An adhesive composition comprising:
a monomer in an amount of about 15 percentage by weight (wt %) to about 30 wt % with respect to the total weight of the adhesive composition; an oligomer in an amount of about 20 wt % to about 40 wt % with respect to the total weight of the adhesive composition; a rubber-based elastic component in an amount of about 25 wt % to about 50 wt% with respect to the total weight of the adhesive composition; and a photopolymerization initiator in an amount of about 2 wt % to 7 wt % with respect to the total weight of the adhesive composition, wherein the photopolymerization initiator comprises a first photopolymerization initiator photo-sensitive in a range of a wavelength from about 350 nm to about 370 nm and a second photopolymerization initiator photo-sensitive in a range of a wavelength from about 380 nm to about 390 nm, and the first photopolymerization initiator and the second photopolymerization initiator have a content ratio of about 5˜2:1.

2 . The adhesive composition of claim 1 , wherein the first photopolymerization initiator is represented by at least one of the following Chemical Formulas 1 through 3:

3 . The adhesive composition of claim 1 , wherein the second photopolymerization initiator is represented by the following Chemical Formula 4:

4 . The adhesive composition of claim 1 , wherein the monomer is at least one selected from the group consisting of isobornyl acrylate, n-octyl acrylate, tetrahydrofurfuryl acrylate, and 4-hydroxy butyl acrylate.

5 . The adhesive composition of claim 1 , wherein the oligomer is at least one selected from the group consisting of urethane (meth)acrylate and ester (meth)acrylate that have a weight average molecular weight(Mw) in a range of about 5,000 Mw to about 50,000 Mw.

6 . The adhesive composition of claim 1 , wherein the rubber-based elastic component is at least one selected from the group consisting of polybutadiene and polyisoprene that have a weight average molecular weight (Mw) in a range of about 10,000 Mw to about 100,000 Mw.

7 . A method of manufacturing a display device comprising:
coating an adhesive composition on a surface of a display panel; performing a first curing of the adhesive composition using a first light source; disposing a window on the adhesive composition subject to the first curing and compressing the window toward the display panel; and performing a second curing of the adhesive composition subject to the first curing by irradiating light on the window using a second light source, wherein the adhesive composition comprises: a monomer in an amount of about 15 wt % to about 30 wt % with respect to the total weight of the adhesive composition; an oligomer in an amount of about 20 wt % to about 40 wt % with respect to the total weight of the adhesive composition; and a rubber-based elastic component in an amount of about 25 wt % to about 50 wt % with respect to the total weight of the adhesive composition; a photopolymerization initiator in an amount of about 2 wt % to 7 wt % with respect to the total weight of the adhesive composition, wherein the photopolymerization initiator comprises a first photopolymerization initiator having a photo-sensitive range of a wavelength from about 350 nm to about 370 nm and a second photopolymerization initiator having a photo-sensitive range of a wavelength from about 380 nm to about 390 nm, the first photopolymerization initiator and the second photopolymerization initiator have a content ratio (i.e., weight ratio) of about 5˜2:1, and the second light source emits light having a wavelength longer than that of the first light source.

8 . The method of claim 7 , wherein the first photopolymerization initiator is represented by at least one of the following Chemical Formulas 1 to 3:

9 . The method of claim 7 , wherein the second photopolymerization initiator is represented by the following Chemical Formula 4:

10 . The method of claim 7 , wherein the first light source emits an ultraviolet ray having a wavelength in a range of about 350 nm to about 370 nm.

11 . The method of claim 7 , wherein the second light source emits an ultraviolet ray having a wavelength in a range of about 380 nm to about 390 nm.

12 . The method of claim 7 , wherein the display panel is one of a liquid crystal display panel and an organic light emitting diode display panel.

13 . A display device comprising:
a display panel; an adhesive layer on the display panel; and a window on the adhesive layer, wherein the adhesive layer comprises an adhesive polymer resin, a rubber-based elastic component, and a photopolymerization initiator, and the photopolymerization initiator comprises a first photopolymerization initiator having a maximum absorption wavelength in a range of about 350 nm to about 370 nm and a second photopolymerization initiator having a maximum absorption wavelength in a range of about 380 nm to about 390 nm.

14 . The display device of claim 13 , wherein the adhesive layer has:
an elasticity in a range of about 0.10 Mpa to about 0.30 Mpa; an elongation index in a range of about 100% to about 300%; a refractive index in a range of about 1.49 to about 1.53; a transmittance more than about 92%; and a glass transition temperature in a range of about −10° C. to about −5° C.

Assignees

• Samsung Display Co Ltd

Inventors

• Kwack Junho
• You Jongsung

Classifications

• B32B37/12

  characterised by using adhesives · CPC title

• B32B2305/72

  Cured, e.g. vulcanised, cross-linked · CPC title

• B32B2037/1253

  curable adhesive · CPC title

• C09J109/00 Primary

  Adhesives based on homopolymers or copolymers of conjugated diene hydrocarbons · CPC title

• B32B2457/20

  Displays, e.g. liquid crystal displays, plasma displays · CPC title