# US 11,898,066 B2 · Adhesive member and display device including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,898,066 B2 - Document ID: US11898066B2 - Status: Granted - Kind: B2 - Application number: 17/859,494 - Filed: 2022-07-07 - Published: 2023-05-04 - Granted: 2024-02-13 - Earliest claimed: 2021-10-27 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Tetsuya Fujiwara - Web page: https://patentgrep.com/patent/US11898066B2 ## CPC - C09J 175/06: from polyesters - C09J 175/16: having terminal carbon-to-carbon unsaturated bonds - C08F 290/067: {Polyurethanes; Polyureas} - C09J 7/385: {Acrylic polymers} - C09J 151/08: grafted on to macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds - C09J 2203/318: for the production of liquid crystal displays - C09J: ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES (preparation of glue or gelatine C09H) - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS ## Abstract An adhesive member includes a polymer derived from a resin composition. The resin composition includes at least one (meth)acrylate monomer, at least one urethane (meth)acrylate oligomer, and at least one photoinitiator. The adhesive member has a glass transition temperature in a range of about −70° C. to about −30° C., a 180° peel force of about 800 gf/25 mm or greater at a temperature of 25° C., and a deformation recovery rate in a range of about 75% to about 100% at temperatures of −20° C. and 60° C. The deformation recovery rate satisfies the following equation: X2=[1−(X1/25)]×100%, where X1 denotes a shear strain measured 600 seconds after removing a shear stress applied in a way such that the adhesive member has a shear strain of 25% at the temperatures of −20° C. and 60° C., and X2 denotes the deformation recovery rate. ## Claims ### Claim 1 An adhesive member comprising a polymer derived from a resin composition including at least one (meth)acrylate monomer, at least one urethane (meth)acrylate oligomer, and at least one photoinitiator, wherein the at least one (meth)acrylate monomer comprises 2-ethylhexyl-diglycol acrylate, wherein the adhesive member has a glass transition temperature in a range of about −70° C. or greater to less than about −30° C., a 180° peel force of about 800 gf/25 mm or greater for a glass substrate at a temperature of 25° C., and a deformation recovery rate in a range of about 75% or greater or to less than about 100% at temperatures of −20° C. and 60° C., wherein the deformation recovery rate satisfies the following equation: X2=[1−(X1/25)]×100%, wherein X1 denotes a shear strain measured 600 seconds after removing a shear stress applied in a way such that the adhesive member has a shear strain of 25% at the temperatures of −20° C. and 60° C., and X2 denotes the deformation recovery rate. ### Claim 2 (depends on 1) The adhesive member of claim 1, wherein the adhesive member has a first stress relaxation ratio in a range of about 75% or greater to less than about 95% for the shear strain of 25% at a temperature of −20° C., wherein the first stress relaxation ratio satisfies the following equation: Y3=[1−(Y1/Y2)]×100%, wherein Y1 denotes a first shear stress measured immediately after the shear strain of 25% is exhibited at the temperature of −20° C., Y2 denotes a second shear stress measured 10 seconds after the shear strain of 25% is exhibited at the temperature of −20° C., and Y3 denotes the first stress relaxation ratio. ### Claim 3 (depends on 1) The adhesive member of claim 1, wherein the adhesive member has a second stress relaxation ratio in a range of about 1% or greater to about 30% for the shear strain of 25% at a temperature of 60° C., wherein the second stress relaxation ratio satisfies the following equation: Z3=[1−(Z1/Z2)]×100%, wherein Z1 denotes a third shear stress measured immediately after the shear strain of 25% is exhibited at the temperature of 60° C., Z2 denotes a fourth shear stress measured 10 seconds after the shear strain of 25% is exhibited at the temperature of 60° C., and Z3 denotes the second stress relaxation ratio. ### Claim 4 (depends on 1) The adhesive member of claim 1, wherein the resin composition has a viscosity in a range of about 5 cP or greater to less than about 50 cP as measured at a temperature of 25° C. according to JIS K 2283. ### Claim 5 (depends on 1) The adhesive member of claim 1, wherein the (meth)acrylate monomer has a weight average molecular weight in a range of about 100 to about 500, and the urethane (meth)acrylate oligomer has a weight average molecular weight in a range of about 10,000 or greater to less than about 40,000. ### Claim 6 (depends on 1) The adhesive member of claim 1, wherein the urethane (meth)acrylate oligomer comprises a plurality of acryl groups. ### Claim 7 (depends on 1) The adhesive member of claim 1, wherein the at least one (meth)acrylate monomer further comprises 2-ethylhexyl acrylate, 4-hydroxybutyl acrylate, and/or tetrahydrofurfuryl acrylate. ### Claim 8 A display device comprising: a display panel; a window disposed on the display panel; and an adhesive member disposed between the display panel and the window, wherein the adhesive member includes a polymer derived from a resin composition having at least one (meth)acrylate monomer, at least one urethane (meth)acrylate oligomer, and at least one photoinitiator, where the at least one (meth)acrylate monomer comprises 2-ethylhexyl-diglycol acrylate, wherein the adhesive member has a glass transition temperature in a range of about −70° C. or to about −30° C., a 180° peel force of about 800 gf/25 mm or greater for a glass substrate at a temperature of 25° C., and a deformation recovery rate in a range of about 75% or greater to less than about 100% at temperatures of −20° C. and 60° C., wherein the deformation recovery rate satisfies the following equation: X2=[1−(X1/25)]×100%, wherein X1 denotes a shear strain measured 600 seconds after removing a shear stress applied in a way such that the adhesive member has a shear strain of 25% at the temperatures of −20° C. and 60° C., and X2 denotes the deformation recovery rate. ### Claim 9 (depends on 8) The display device of claim 8, wherein the adhesive member has a first stress relaxation ratio in a range of about 75% or greater to less than about 95% for the shear strain of 25% at a temperature of −20° C., wherein the first stress relaxation ratio satisfies the following equation: Y3=[1−(Y1/Y2)]×100%, wherein Y1 denotes a first shear stress measured immediately after the adhesive member exhibits the shear strain of 25% at the temperature of −20° C., Y2 denotes a second shear stress measured 10 seconds after the adhesive member exhibits the shear strain of 25% at the temperature of −20° C., and Y3 denotes the first stress relaxation ratio. ### Claim 10 (depends on 8) The display device of claim 8, wherein the adhesive member has a second stress relaxation ratio in a range of about 1% or greater to less than about 30% for the shear strain of 25% at a temperature of 60° C., wherein the second stress relaxation ratio satisfies the following equation: Z3=[1−(Z1/Z2)]×100%, wherein Z1 denotes a third shear stress measured immediately after the adhesive member exhibits the shear strain of 25% at the temperature of 60° C., Z2 denotes a fourth shear stress measured 10 seconds after the adhesive member exhibits the shear strain of 25% at the temperature of 60° C., and Z3 denotes the second stress relaxation ratio. ### Claim 11 (depends on 8) The display device of claim 8, wherein the resin composition has a viscosity in a range of about 5 cP or greater to less than about 50 cP as measured at a temperature of 25° C. according to JIS K 2283. ### Claim 12 (depends on 8) The display device of claim 8, wherein the (meth)acrylate monomer has a weight average molecular weight in a range of about 100 to about 500, and the urethane (meth)acrylate oligomer has a weight average molecular weight in a range of about 10,000 or greater to less than about 40,000. ### Claim 13 (depends on 8) The display device of claim 8, wherein the adhesive member has a thickness in a range of about 50 μm to about 200 μm. ### Claim 14 (depends on 8) The display device of claim 8, wherein the adhesive member is formed by providing the resin composition on one surface of the window or on one surface of the display panel, and then ultraviolet curing the resin composition. ### Claim 15 (depends on 8) The display device of claim 8, further comprising: a light control layer disposed between the adhesive member and the window; and an optical adhesive layer disposed between the light control layer and the window, wherein the optical adhesive layer includes a polymer derived from the resin composition, and wherein the light control layer is a polarizing plate or a color filter layer. ### Claim 16 (depends on 15) The display device of claim 15, wherein the optical adhesive layer has a 180° peel force of about 800 gf/25 mm or greater at a temperature of 25° C., wherein the 180° peel force is a peel force for a glass substrate. ### Claim 17 (depends on 8) The display device of claim 8, further comprising: an input sensing unit disposed on the display panel, wherein the adhesive member is disposed between the display panel and the input sensing unit or between the input sensing unit and the window. ### Claim 18 (depends on 17) The display device of claim 17, wherein the display panel comprises a display element layer and an encapsulation layer disposed on the display element layer, wherein the input sensing unit is disposed on the encapsulation layer, and the adhesive member is disposed on the input sensing unit. ### Claim 19 (depends on 8) The display device of claim 8, wherein at least one folding region is defined in the display device, wherein the folding region has a radius of curvature of about 5 mm or less. ### Claim 20 (depends on 8) The display device of claim 8, wherein the at least one (meth)acrylate monomer further comprises 2-ethylhexyl acrylate, 4-hydroxybutyl acrylate, and/or tetrahydrofurfuryl acrylate.