Patent · US Expired

Novel benzofuran dyes

US4900831A · kind A · utility

1Cited by
9References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 9, 1988
Grant dateFeb 13, 1990
Priority date
Expiry dateMay 9, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09B23/105
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A 6-tertiary amino-2-(Z.dbd.CH--)benzofuran dye is disclosed, where Z represents the atoms providing an electron withdrawing group and a conjugated methine linkage completing a resonant dye chromophore including the 6-tertiary amino group as an electron donor and the electron withdrawing group as an electron acceptor. The dyes are formed by condensing a 6-tertiary amino-2-formylbenzofuran with an electron withdrawing dye nucleus precursor containing an active methyl or methylene site. The dyes exhibit bathochromically shifted absorption peaks.

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