Patent · US Expired

Dyestuff preparations and processes for their production

US4111649A · kind A · utility

1Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 1975
Grant dateSep 5, 1978
Priority date
Expiry dateDec 23, 1995

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09B69/045
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A process for the manufacture of stable, concentrated solutions of water-soluble tertiary ammonium salts of disazo dyestuffs is described, which comprises diazotizing 2 moles of the same primary aromatic amine or 1 mole each of different primary aromatic amines and reacting the diazo mixture with 1 mole of a compound which is able to couple with diazonium salt in at least 2 positions, in the presence of at least 2 moles of a tertiary amine and optionally other assistants. The resulting solutions prove stable even on prolonged storing at room temperature and are not affected by frost. The solutions are miscible in any ratio with water or, in part, also with suitable water-miscible organic solvents.

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