# US 9,751,241 B2 · Foam gasket and bonding tape based on polyurethane dispersions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,751,241 B2 - Document ID: US9751241B2 - Status: Granted - Kind: B2 - Application number: 14/300,813 - Filed: 2014-06-10 - Published: 2014-12-18 - Granted: 2017-09-05 - Earliest claimed: 2013-06-13 - Assignees: Saint-Gobain Performance Plastics Corporation - Applicants: Saint-Gobain Performance Plastics Corporation - Inventors: Jing Guan; Yue Dong; Georges Moineau - Web page: https://patentgrep.com/patent/US9751241B2 ## CPC - B29C 39/203: {Making multilayered articles} - B29C 39/18: incorporating preformed parts or layers, e.g. casting around inserts or for coating articles {(B29C39/206 takes precedence)} - B29K 2075/00: Use of {PU, i.e.} polyureas or polyurethanes {or derivatives thereof}, as moulding material - B29K 2995/0077: Yield strength; Tensile strength - B29K 2995/0087: Wear resistance - B29L 2007/002: {Panels; Plates; Sheets} - B29L 2009/005: {coated} - B29L 2031/265: {Packings, Gaskets} - Y10T 428/1452: Polymer derived only from ethylenically unsaturated monomer - Y10T 428/1457: Silicon - Y10T 428/1462: Polymer derived from material having at least one acrylic or alkacrylic group or the nitrile or amide derivative thereof [e.g., acrylamide, acrylate ester, etc.] - Y10T 428/1476: Release layer - Y10T 428/2495: Thickness [relative or absolute] - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A polymer sheet includes a polyurethane core. The polyurethane core has a first major surface and a second major surface opposite the first major surface. The polymer sheet can have at least one functional layer overlying a major surface. The polymer sheet has a thickness tPS. The polyurethane core has a thickness tPC. In embodiments tPC can be at least 0.3 tPS. The polyurethane core can have at least one of the following property: (i) a Scratch Resistance Rating, as further described herein, of not greater than about 10 wt %, (ii) an elongation at break of at least 200%, (iii) a tensile strength at break of at least 0.3 MPa, (iv) a loss of tensile strength of not greater than about 30% when exposed to UV light according to standard SAE J1960 (Rev. August 2003). The polymer sheet can be used for gaskets or bonding tapes. ## Claims ### Claim 1 A polymer sheet comprising: a polyurethane core, having a first major surface and a second major surface opposite the first major surface; and at least one functional layer; wherein the polymer sheet has a thickness tPS and the polyurethane core has a thickness tPC, wherein tPC is at least 0.3 tPS, wherein the polyurethane core comprises polyurethane polymer, and wherein the polyurethane core has a loss of tensile strength when exposed to UV light according to standard SAE J1960 (Rev. August 2003) of not greater than 30%. ### Claim 2 (depends on 1) The polymer sheet according to claim 1, wherein the polymer sheet has a primary aspect ratio of at least 400. ### Claim 3 (depends on 1) The polymer sheet according to claim 1, wherein the functional layer is selected from the group consisting of a permanent liner, a release liner, a topcoat, and an adhesive. ### Claim 4 (depends on 1) The polymer sheet according to claim 1, wherein the functional layer comprises a permanent liner, and the permanent liner comprises a thermoplastic selected from the group consisting of polyethylene, polyester, and polyimide. ### Claim 5 (depends on 1) The polymer sheet according to claim 1, wherein the functional layer comprises a permanent liner, and the permanent liner comprises ultra-high molecular weight polyethylene. ### Claim 6 (depends on 1) The polymer sheet according to claim 1, wherein the functional layer is selected from the group consisting of a permanent liner, a release liner, and an adhesive layer, and wherein the functional layer has a thickness of in a range of from 0.01 mm to 0.1 mm. ### Claim 7 (depends on 1) The polymer sheet according to claim 1, wherein the functional layer is a release liner, and wherein the release liner includes a-polyester, polyethylene, polypropylene, or paper. ### Claim 8 (depends on 1) The polymer sheet according to claim 1, wherein the functional layer is a topcoat, and wherein the topcoat has a thickness in a range of from 0.001 mm to 0.01 mm. ### Claim 9 (depends on 1) The polymer sheet according to claim 1, wherein the functional layer is a pressure sensitive adhesive selected from the group consisting of an acrylic adhesive, a silicon adhesive, a rubber hot melt adhesive, an acrylic copolymer, and a rubber acrylic copolymer. ### Claim 10 (depends on 1) The polymer sheet according to claim 1, wherein the polymer sheet is in a form of a roll. ### Claim 11 (depends on 1) The polymer sheet according to claim 1, wherein the polyurethane core has a thickness in a range of from 0.2 mm to 3.0 mm. ### Claim 12 (depends on 1) The polymer sheet according to claim 1, wherein the loss of tensile strength when exposed to UV light according to standard SAE J1960 (Rev. August 2003) is not greater than 25%. ### Claim 13 (depends on 1) The polymer sheet according to claim 1, wherein the polyurethane core has a compression force deflection at 25% compression of at least 3 kPa. ### Claim 14 (depends on 1) The polymer sheet according to claim 1, wherein the polyurethane core when exposed to UV light according to standard SAE J1960 (Rev. August 2003) has a discoloration ΔE of not greater than 4.0. ### Claim 15 (depends on 1) The polymer sheet according to claim 1, wherein the polyurethane core when exposed to UV light according to standard SAE J1960 (Rev. August 2003) has a yellowing Δb of not greater than 2. ### Claim 16 (depends on 1) The polymer sheet according to claim 1, wherein the polyurethane core is free of pigment. ### Claim 17 A method of preparing a polymer sheet, the method comprising: frothing a polyurethane dispersion into a froth; casting the froth onto a liner; treating the froth to have a uniform thickness; drying the froth to form a polyurethane core having a thickness of at least 0.5 of a total thickness of the polymer sheet, wherein the polyurethane core comprises polyurethane polymer, wherein the polyurethane core has a loss of tensile strength when exposed to UV light according to standard SAE J1960 (Rev. August 2003) of not greater than about 30%. ### Claim 18 (depends on 17) The method according to claim 17 further comprising casting a topcoat layer onto the polymer sheet, wherein the topcoat layer comprises a polyurethane coating, and wherein the topcoat has a thickness in a range of from 0.001 mm to 0.01 mm. ### Claim 19 An assembly comprising: a first member; a second member; and a gasket; wherein the gasket includes a polyurethane core, wherein the polyurethane core has a first major surface and a second major surface opposite the first major surface, wherein the gasket is compressed between the first member and the second member at a compression of at least about 10%, wherein the polyurethane core comprises a polyurethane polymer, and wherein the polyurethane core has a loss of tensile strength when exposed to UV light according to standard SAE J1960 (Rev. August 2003) of not greater than 30%. ### Claim 20 (depends on 19) The assembly according to claim 19, wherein the assembly is an electronic device and wherein the first member and the second member are components of the electronic device.