Patent · US Expired

Process for the preparation of water-soluble dyestuffs with a low salt content

US4340389A · kind A · utility

9Cited by

5References

7Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Konrad Nonn
Joachim Laser · Cologne, DE
Karlheinz Wolf · Leverkusen, DE
Reinhold Hornle
Erich Istel · Dormagen, DE

Key dates

Filing date	Apr 15, 1981
Grant date	Jul 20, 1982
Priority date	—
Expiry date	Apr 15, 2001

Classification

Technology area (CPC D)Textiles; Paper
CPC primaryD06L4/664
WIPO fieldBasic materials chemistry
WIPO sectorChemistry

Abstract

Process for the preparation of water-soluble dyestuffs with a low salt content, characterized in that the water-soluble dyestuffs are salted out from their aqueous solutions and/or dispersions by adding salts which are volatile at temperatures of about 40.degree. C. to about 250.degree. C. under a pressure of about 10 mm Hg to about 760 mm Hg, the dyestuffs are isolated and the volatile salts are volatilized during the drying process.

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