# US 4,391,767 A · Coated polyester films > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,391,767 A - Document ID: US4391767A - Status: Granted - Kind: A - Application number: 06/188,144 - Filed: 1980-09-17 - Granted: 1983-07-05 - Earliest claimed: 1969-07-15 - Assignees: Imperial Chemical Industries PLC - Inventors: Gordon E. A. Pears - Web page: https://patentgrep.com/patent/US4391767A ## CPC - G03C 1/93: Macromolecular substances therefor - B29C 48/00: Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor (extrusion blow-moulding B29C49/04) - B29C 48/08: flexible, e.g. films - B29C 55/026: {of preformed plates or sheets coated with a solution, a dispersion or a melt of thermoplastic material} - C08J 7/042: {with two or more layers, where at least one layer of a composition contains a polymer binder} - C08J 7/043: Improving the adhesiveness of the coatings per se, e.g. forming primers (adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50) - C08J 7/044: Forming conductive coatings; Forming coatings having anti-static properties - C08J 7/046: Forming abrasion-resistant coatings; Forming surface-hardening coatings - C08J 11/06: without chemical reactions - C08J 2367/02: Polyesters derived from dicarboxylic acids and dihydroxy compounds; (C08J2367/06 takes precedence) - C08J 2433/12: Homopolymers or copolymers of methyl methacrylate - Y02W 30/62: Plastics recycling; Rubber recycling - Y10T 428/24736: Ornamental design or indicia - Y10T 428/31797: Next to addition polymer from unsaturated monomers - G03C: PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES (for photomechanical purposes G03F); PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY (photographic processes characterised by the use or manipulation of apparatus classifiable per se in subclass G03B, see G03B; photomechanical production of textured or patterned surfaces G03F; electrophotography, magnetography G03G) - 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) - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Coating polyester films between the longitudinal and transverse drawing stages of the biaxial orientation process with a non-heat sealing primer coating which may be reclaimable. ## Claims ### Claim 1 A process for the production of a synthetic linear polyester film which comprises melt extruding a substantially amorphous polyester film, drawing the film in the longitudinal direction, thereafter applying a primer coating comprising a thermosetting acrylic or methacrylic composition, wherein the acrylic or methacrylic component is crosslinkable, to one or both sides of said film, then drawing the coated film in the transverse direction, and heat setting the biaxially oriented and coated film, whereby a primer coating of the thermoset acrylic or methacrylic composition, wherein the acrylic or methacrylic component is thermoset, of thickness of at least 10.sup.-7 inch is obtained, and then recycling the coated film by re-extruding the same with fresh polyester. ### Claim 2 (depends on 1) A process according to claim 1, in which the coating composition comprises a polymer or copolymer of acrylic acid or methacrylic acid or their esters containing crosslinkable functional groups. ### Claim 3 (depends on 2) A process according to claim 2, in which the functional groups of the coating polymer or copolymer are crosslinked with an amine/formaldehyde condensation product. ### Claim 4 (depends on 1) A process according to claim 1, in which the film resulting from the extrusion of the recycled coated film and fresh polyester comprises up to 1.0% by weight of the thermosetting acrylic or methacrylic coating composition. ### Claim 5 (depends on 2) A process according to claim 2, in which said polymer or copolymer comprises ethyl acrylate and is admixed with the condensation product of an amine with formaldehyde. ### Claim 6 (depends on 1) A process according to claim 1, in which the synthetic linear polyester is polyethylene terephthalate. ### Claim 7 (depends on 1) A process according to claim 1, in which the film is drawn longitudinally before coating to about 3.5 times its original length and the coated film is then drawn transversely to about 3.5 times its original width and the thus drawn film is heat set at about 200.degree. C. ### Claim 8 (depends on 1) A process according to claim 1, in which the film is drawn longitudinally at a temperature of 78.degree. C. to 100.degree. C. and transversely at a temperature of 80.degree. C. to 125.degree. C. ### Claim 9 (depends on 1) A process according to claim 1, in which the thermosetting acrylic or methacrylic composition is derived from a polymer or copolymer of acrylic acid or methacrylic acid containing hydroxy, carboxyl, amide or oxirane functional groups and an amine condensation product.