Patent · US Expired

Purification of crude 9,9-bis-(4-hydroxyphenyl)-fluorene

US4049721A · kind A · utility

8Cited by
0References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 7, 1976
Grant dateSep 20, 1977
Priority date—
Expiry dateSep 7, 1996

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C2603/18
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Certain impurities found in 9,9-bis(4-hydroxyphenyl)-fluorene are removed by treatment of the latter with a methanol-water mixture and thereafter isolating the purified fluorene.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.