# US 2019/0375929 A1 · Melt processible fluororesin composition and injection molded article formed from same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0375929 A1 - Document ID: US20190375929A1 - Status: Published application - Kind: A1 - Application number: 16/431,030 - Filed: 2019-06-04 - Published: 2019-12-12 - Earliest claimed: 2018-06-07 - Assignees: Chemours-Mitsui Fluoroproducts Co., Ltd. - Applicants: Chemours-Mitsui Fluoroproducts Co., Ltd. - Inventors: Takahiro Nishimura; Toshiki Kitagawa - Web page: https://patentgrep.com/patent/US20190375929A1 ## CPC - C08L 27/18: Homopolymers or copolymers or tetrafluoroethene - B29C 45/0001: {characterised by the choice of material} - B29C 45/0025: {Preventing defects on the moulded article, e.g. weld lines, shrinkage marks (preventing defects on the preformed parts or layers B29C45/14836)} - C08L 27/22: modified by chemical after-treatment - B29K 2027/18: PTFE, i.e. polytetrafluoroethylene {, e.g. ePTFE, i.e. expanded polytetrafluoroethylene} - B29K 2995/0077: Yield strength; Tensile strength - C08L 2201/08: Stabilised against heat, light or radiation or oxydation - C08L 2205/025: containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure - C08L 2205/03: containing three or more polymers in a blend - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - 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 ## Abstract Provided is a melt processible fluororesin composition for injection molding of articles that has melt flow that facilitates injection molding, that can enhance strength of a fluororesin weld line area in an injection molded article, and that achieves excellent release from a mold. The fluororesin composition includes two or more types of melt processible fluororesins having different melt flow rates; one of the melt processible fluororesins being a high melt flow rate melt processible fluororesin having a melt flow rate of 35 g/10 min or greater, and another being a low melt flow rate melt processible fluororesin having a melt flow rate of 10 g/10 min or greater but less than 35 g/10 min; and wherein the ratio of the melt flow rate (MFRa) of the high MFR melt processible fluororesin to the melt flow rate (MFRb) of the low MFR melt processible fluororesin (MFRa/MFRb) is from 1 to 10. ## Claims ### Claim 1 A melt processible fluororesin composition comprising: two or more types of melt processible fluororesins having melt flow rates that are different from each other; one of the two or more types of melt processible fluororesins being a high melt flow rate melt processible fluororesin having a melt flow rate of 35 g/10 min or greater, and another being a low melt flow rate melt processible fluororesin having a melt flow rate of 10 g/10 min or greater but less than 35 g/10 min, and wherein the ratio of the melt flow rate (MFRa) of the high melt flow rate melt processible fluororesin to the melt flow rate (MFRb) of the low melt flow rate melt processible fluororesin (MFRa/MFRb) is greater than 1 but less than or equal to 10. ### Claim 2 (depends on 1) The melt processible fluororesin composition according to claim 1, wherein said melt processible fluororesin composition has a melt flow rate of from 10 to 100 g/10 min. ### Claim 3 (depends on 1) The melt processible fluororesin composition according to claim 1, wherein the content of the high melt flow rate melt processible fluororesin is from 5 to 95 wt. % of the total amount of the melt processible fluororesins. ### Claim 4 (depends on 1) The melt processible fluororesin composition according to claim 1, wherein the high melt flow rate melt processible fluororesin and the low melt flow rate melt processible fluororesin are tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymers (PFA). ### Claim 5 (depends on 1) The melt processible fluororesin composition according to claim 1, further comprising from 0.01 to 1 wt. % of a high molecular weight polytetrafluoroethylene (PTFE) based on the total weight of melt processible fluororesins and polytetrafluoroethylene. ### Claim 6 (depends on 4) The melt processible fluororesin composition according to claim 4, wherein the content of perfluoro(alkyl vinyl ether) in the high melt flow rate tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymer is from 1.5 to 5.0 mol %, and the content of perfluoro(alkyl vinyl ether) in the low melt flow rate tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymer is from 1.0 to 4.0 mol %. ### Claim 7 (depends on 1) The melt processible fluororesin composition according to claim 1, wherein at least one of said high melt flow rate melt processible fluororesin and said low melt flow rate melt processible fluororesin are fluorinated so as to reduce the number of fluororesin chain unstable endgroups and replace such endgroups with —CF3 endgroups. ### Claim 8 (depends on 1) The melt processible fluororesin composition according to claim 1, wherein, i) said composition is fabricated in accordance with ASTM D-2116 into a micro dumbbell-shaped test piece, by injection-molding said melt processible fluororesin composition at an injection pressure and holding pressure of 50 MPa to form a molded sheet having a weld line and a thickness of 1.9±0.5 mm, and cutting from said molded sheet said micro dumbbell-shaped test piece including said weld line, ii) said micro dumbbell-shaped test piece is subjected to a tensile fatigue test performed under conditions: distance between supports of 22 mm, tensile test speed of 200 mm/min, 23° C., sinusoidal wave, and stress ratio of 0.1, to generate tensile fatigue test results, iii) said tensile fatigue test results are plotted in a plot of stress at break in MPa on the Y axis versus cycle number in logarithmic scale on the X axis, and iv) the equation Y=a*ln(X)+b is fitted to said tensile fatigue test results by the least squares method, wherein when X is at least 1,000, a Y value of greater than 14.5 MPa and a value of the slope (a) of greater than −0.15 are obtained. ### Claim 9 (depends on 1) An injection molded article formed by subjecting the melt processible fluororesin composition described in claim 1 to injection molding. ### Claim 10 (depends on 9) The injection molded article of claim 9, wherein said article contains at least one weld line.