公开(公告)号：US20220235156A1

公开(公告)日：2022-07-28

申请号：US17659182

申请日：2022-04-14

Applicant: AGC INC.

Inventor： Shinya HIGUCHI ,  Masahiro TAKAZAWA ,  Yingwei LAI ,  Shiro EBATA ,  Takehiro KOSE

IPC: C08F114/26

Abstract: To provide a method for producing an aqueous dispersion of polytetrafluoroethylene, whereby formation of fluorinated oligomers as byproducts is little and CFT of a coating film to be formed is large.
A method for producing an aqueous dispersion of polytetrafluoroethylene, which comprises step A1 of polymerizing a non-fluorinated monomer in an aqueous medium to obtain a solution 1 containing a polymer comprising units based on said non-fluorinated monomer, step A2 of conducting polymerization of tetrafluoroethylene in said solution 1 without substantially adding a surfactant to said solution 1, to obtain an aqueous emulsion containing polytetrafluoroethylene particles, and step A3 of adding a nonionic surfactant to said aqueous emulsion, and then concentrating said aqueous emulsion to obtain an aqueous dispersion of polytetrafluoroethylene, wherein the amount of said non-fluorinated monomer used is at most 200 mass ppm to the amount of said tetrafluoroethylene supplied to the polymerization system.

公开(公告)号：US20200207880A1

公开(公告)日：2020-07-02

申请号：US16814106

申请日：2020-03-10

Applicant: AGC Inc.

Inventor： Shinya HIGUCHI ,  Shiro EBATA ,  Takehiro KOSE

IPC: C08F2/16 ,  C08F214/26 ,  C08J3/16

Abstract: To provide a novel method for producing a modified PTFE.The method for producing a modified polytetrafluoroethylene comprises polymerizing tetrafluoroethylene in an aqueous medium in which a polymer comprising units based on a fluorine-free monomer is present.

公开(公告)号：US20210380794A1

公开(公告)日：2021-12-09

申请号：US17411227

申请日：2021-08-25

Applicant: AGC Inc.

Inventor： Yukiko HATTORI ,  Tsuyoshi KAWAI ,  Takeshi YAMADA ,  Takehiro KOSE

IPC: C08L27/18 ,  C08F214/26 ,  C08J3/24 ,  C08L21/02

Abstract: To provide a method for producing crosslinked rubber excellent in hardness and transparency.
The method for producing crosslinked rubber of the present invention is a method for producing crosslinked rubber, which comprises crosslinking a fluorinated copolymer in a composition comprising the fluorinated copolymer, a crosslinking agent and a crosslinking co-agent, wherein the fluorinated copolymer is a copolymer having units based on tetrafluoroethylene and units based on a perfluoro(alkyl vinyl ether), the content of the units based on tetrafluoroethylene is from 65 to 90 mol % to all units of the fluorinated copolymer, in the composition, the content of the crosslinking agent is from 0.03 to 0.7 part by mass to 100 parts by mass of the fluorinated copolymer, the content of the crosslinking co-agent is from 0.1 to 2.5 parts by mass to 100 parts by mass of the fluorinated copolymer, and the hardness is from 65 to 100.

公开(公告)号：US20230357515A1

公开(公告)日：2023-11-09

申请号：US18352379

申请日：2023-07-14

Applicant: AGC Inc.

Inventor： Shinya HIGUCHI ,  Kaori ABE ,  Takehiro KOSE

IPC: C08J3/05 ,  C08F114/26

CPC classification number: C08J3/05 ,  C08F114/26 ,  C08J2327/18

Abstract: To provide a method for producing an aqueous polytetrafluoroethylene dispersion, whereby the formation of fluorinated oligomers as byproducts is minimized, CFT of the formed coating film is large, and a highly concentrated aqueous polytetrafluoroethylene dispersion is easily obtainable. The method for producing an aqueous polytetrafluoroethylene dispersion, which comprises step A1 of polymerizing a non-fluorinated monomer in an aqueous medium to obtain a solution 1 containing a polymer containing units based on the non-fluorinated monomer, step A2 of conducting polymerization of tetrafluoroethylene in the solution 1 without substantially adding a surfactant to the solution 1, to obtain an aqueous emulsion containing polytetrafluoroethylene particles, and step A3 of adding a nonionic surfactant to the aqueous emulsion at a rate of from 10 to 150 mass % to the mass of PTFE contained in the aqueous emulsion, and subsequently concentrating the aqueous emulsion to obtain an aqueous polytetrafluoroethylene dispersion, wherein the amount of the non-fluorinated monomer used, to the amount of the tetrafluoroethylene supplied to the polymerization system, is at most 200 mass ppm.

公开(公告)号：US20210163648A1

公开(公告)日：2021-06-03

申请号：US17173455

申请日：2021-02-11

Applicant: AGC Inc.

Inventor： Satoko YASUDA ,  Takehiro KOSE ,  Yukiko HATTORI ,  Toshikazu YONEDA

IPC: C08F214/26 ,  C08F214/22 ,  C08F214/28 ,  C08F214/16 ,  C08F236/20 ,  C08L23/12

Abstract: To provide a fluorinated copolymer excellent in low temperature properties and crosslinking property as a fluororubber, and a method for producing it.
A fluorinated copolymer which has units based on tetrafluoroethylene, units based on propylene and units based on a compound represented by the following formula 1, and which has either one or both of iodine atoms and bromine atoms: CF2═CFO(Rf1O)nRf2  formula 1 wherein Rf1 is a C1-3 perfluoroalkylene group, Rf2 is a C1-6 perfluoroalkyl group, n is an integer of from 1 to 4, and in a case where n is from 2 to 4, a plurality of Rf1 may be the same or different.