The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 13, 2026
Filed:
Mar. 24, 2021
Tosoh Corporation, Shunan, JP;
Kota Sakaguchi, Yokkaichi, JP;
Kazunari Iwanaga, Yokkaichi, JP;
Tomoya Shimono, Yokkaichi, JP;
Tomonari Nagai, Yokkaichi, JP;
Hiroshi Yamakawa, Yokkaichi, JP;
TOSOH CORPORATION, Shunan, JP;
Abstract
The present invention pertains to: a fluororesin that includes a residue unit represented by formula (1), and a terminal group represented by formula (2); and a fluororesin that includes a residue unit represented by formula (1) and has a transmittance of 50% or more measured at an optical path length of 10 mm and a wavelength of 275 nm when dissolved in perfluorohexane to produce a 10 wt % perfluorohexane solution. In formula (1): Rf, Rf, Rf, and Rfeach independently represent one selected from the group consisting of fluorine atoms, C1-7 linear perfluoroalkyl groups, C3-7 branched perfluoroalkyl groups, or C3-7 cyclic perfluoroalkyl groups; the perfluoroalkyl groups may have an etheric oxygen atom; Rf, Rf, Rf, and Rfmay bond to each other to form a ring having 4 to 8 carbon atoms; and the ring may include an etheric oxygen atom. In formula (2), i is an integer of 3-20. The present invention provides: a fluororesin that includes an oxolane ring, has suppressed yellowing after heating and melting, and especially has reduced discoloration, even in molding of thick products; and a method for producing said fluororesin.