# US 2022/0152904 A1 · A process and an apparatus for manufacturing bi-axially oriented polyester film from rpet > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0152904 A1 - Document ID: US20220152904A1 - Status: Published application - Kind: A1 - Application number: 17/439,579 - Filed: 2020-03-27 - Published: 2022-05-19 - Earliest claimed: 2019-03-15 - Assignees: Polyplex Corporation Limited - Applicants: Polyplex Corporation Limited - Inventors: Pranay Kothari; Krishna Reddy - Web page: https://patentgrep.com/patent/US20220152904A1 ## CPC - B29B 17/02: Separating plastics from other materials - B29C 48/0018: {combined with shaping by orienting, stretching or shrinking, e.g. film blowing (B29C48/0017 takes precedence)} - B29C 48/08: flexible, e.g. films - B29C 48/21: the layers being joined at their surfaces - B29C 55/143: {firstly parallel to the direction of feed and then transversely thereto} - B29D 7/01: Films or sheets - C08J 5/18: Manufacture of films or sheets - C08J 11/24: containing hydroxyl groups - B29B 2017/0015: {Washing, rinsing} - B29B 2017/0272: {Magnetic separation} - B29C 55/005: {characterised by the choice of materials} - B29C 55/12: biaxial - B29K 2067/003: {PET, i.e. poylethylene terephthalate} - B29K 2105/26: Scrap {or recycled material} - B29K 2995/0053: bi-axially - B29L 2007/008: {Wide strips, e.g. films, webs} - C08J 2367/02: Polyesters derived from dicarboxylic acids and dihydroxy compounds; (C08J2367/06 takes precedence) - Y02P 20/582: Recycling of unreacted starting or intermediate materials - Y02W 30/52: Mechanical processing of waste for the recovery of materials, e.g. crushing, shredding, separation or disassembly - Y02W 30/62: Plastics recycling; Rubber recycling - Y02W 30/80: Packaging reuse or recycling, e.g. of multilayer packaging (bio-packaging Y02W90/10) - B29B: PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS - 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) - B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00) - 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) - 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 - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS - Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT ## Abstract The present disclosure relates to a process for producing bi-axially oriented polyester (BOPET) film from the recycled polyethylene terephthalate (RPET) granules. The process involves preparing recycled PET (RPET) granules form post-consumer recycled PET (PCR PET) by depolymerization and polycondensation followed by preparing the biaxially oriented polyethylene terephthalate (BOPET) film having recycled polyethylene terephthalate (RPET) up to 100%. The bi-axially oriented polyester film has good elongation, mechanical and/or thermal properties and are similar in quality to virgin PET films useful in high end food and pharma packaging and industrial applications. ## Claims ### Claim 1 A process for preparing a biaxially oriented polyethylene terephthalate (BOPET) film comprising, the steps of preparing a recycled polyethylene terephthalate (RPET) granules, comprises depolymerization by glycolysis of a pre cleaned PET products to produce monomers, polycondensation of monomers in a polycondensation reactor or an autoclave to produce recycled PET (RPET) granules. preparing the biaxially oriented polyethylene terephthalate film, comprises charging the RPET granules along with a virgin PET granules, to an extruder to obtain a molten polyethylene terephthalate, extruding the molten polyethylene terephthalate through a die, quenching the extruded polyethylene terephthalate on chilled rollers and stretching to obtain biaxially oriented polyethylene terephthalate film. characterized in that, the glycolysis reaction is conducted in an esterification reactor by addition of glycol, at a temperature of 245-255° C. and at a pressure of 0.5-1 bar, and the RPET granules are up to 100% in the mixture of the RPET and virgin PET granules, charged to the extruder. ### Claim 2 (depends on 1) The process as claimed in claim 1, wherein the biaxially oriented polyethylene terephthalate obtained has at least three layers. ### Claim 3 (depends on 1) The process as claimed in claim 1, wherein the biaxially oriented polyethylene terephthalate is an A/B/A or A/B/C configuration, the B layer comprises biaxially oriented polyethylene terephthalate film made from the recycled PET (RPET) and cap layers A and/or C, comprises biaxially oriented polyethylene terephthalate film, made from virgin PET granules, along with inorganic filler. ### Claim 4 (depends on 1) The process as claimed in claim 1, wherein the step of film preparation comprises up to 95% of the recycled PET granules. ### Claim 5 (depends on 1) The process as claimed in claim 1, wherein the step of film preparation comprises up to 90% of the recycled PET granules. ### Claim 6 (depends on 1) The process as claimed in claim 1, wherein the step of pre cleaning of PET products comprises the followings steps, primary washing of PET products by solvent to remove contamination, non PET materials such as poly propylene, poly ethylene, poly vinyl chloride. de brushing the washed PET product for removal of dust and unwanted materials, de-stoning of the PET product for removal of the stones to obtain cleaned PET products. ### Claim 7 (depends on 1) The process as claimed in claim 1, wherein the step of preparing the recycled polyethylene terephthalate (RPET) is followed by filtration for foreign particles removal and de-coloration, before the film preparation step. ### Claim 8 (depends on 1) The process as claimed in claim 1, wherein the PET products are selected from one or more films, sheets, laminate, bottles and flakes, amorphous PET (A-PET), crystalline PET (C-PET), polyester film and post-consumer recycled PET (PCR PCT). ### Claim 9 (depends on 1) The process as claimed in claim 1, wherein the autoclave temperature is 275-295° C. and the batch time is of 3-4 hrs. ### Claim 10 (depends on 1) The process as claimed in claim 1, wherein the autoclave reactor is maintained at vacuum and catalyst is added. ### Claim 11 (depends on 1) The process as claimed in claim 1, wherein the stretching involves machine direction stretching with stretch ratio of 3-3.5, and transverse direction stretching with stretch ratio of 3.8-4.2. ### Claim 12 (depends on 1) The process as claimed in claim 1, wherein the autoclave reactor is added with additives. ### Claim 13 (depends on 1) The process as claimed in claim 1, wherein the biaxially oriented polyethylene terephthalate (BOPET) is a food grade packaging film or pharma products packaging film. ### Claim 14 An apparatus for producing biaxially oriented polyethylene terephthalate (BOPET) film comprises, cleaning device for pre cleaning PET products to be recycled, esterification reactor for converting a pre cleaned PET product to a monomer, autoclave reactor operated at temperature of 275-295° C. and at vacuum pressure, for polycondensation of the monomers to obtain a recycled PET granules, extruders for extruding the recycled PET granules and optionally a virgin PET granules to obtain the molten polyethylene terephthalate (PET), chilled rollers for quenching the molten PET and stretching to obtain biaxially oriented polyethylene terephthalate, characterized in that, the esterification reactor involves glycolysis reaction by addition of glycol, at a temperature of 245-255° C. and at a pressure of 0.5-1 bar, and the RPET granules are up to 100% in the mixture of the RPET and virgin PET charged to the extruder. ### Claim 15 (depends on 14) The apparatus as claimed in claim 14, wherein the cleaning apparatus comprises pre cleaning machine for washing, removing contamination and non-PET materials such as poly propylene, poly ethylene, poly vinyl chloride from the PET flakes, de brushing apparatus for removal of dust and unwanted materials, de stoning apparatus for the removal of the stones to obtain cleaned PET products. magnetic separator for removal of iron and other metal particles.