Process for producing liquid dyestuff preparations

US4329145A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Jochen Koll · Odenthal, DE
• Hans-Heinz Molls · Leverkusen, DE
• Reinhold Hornle
• Erhard Schuffenhauer · Leverkusen, DE
• Horst Brandt · Weiterstadt, DE
• Fritz Bremer · Leverkusen, DE
• Karlheinz Wolf · Leverkusen, DE
• Willy Schiwy · Leverkusen, DE

Key dates

• Filing date: Aug 8, 1980
• Grant date: May 11, 1982
• Expiry date: Aug 8, 2000

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09B67/0096
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Highly concentrated liquid preparations of disperse dyestuffs are obtained with a low consumption of energy by first adding a dispersing agent to the water-moist dyestuff press-cake to convert it into a form in which it is capable of flow, subjecting this product to wet grinding and increasing the dyestuff content of the resulting, insufficiently concentrated dispersion in a second step by means of a membrane separation process, for example pressure permeation.