Aqueous dye preparations containing coumarin dyes

US5531797A · kind A · utility

Assignee

• BASF SE

Inventors

• Rudolf Bermes · Ludwigshafen, DE
• Walter Breitschaft · Ludwigshafen, DE

Key dates

• Filing date: Mar 6, 1995
• Grant date: Jul 2, 1996
• Expiry date: Mar 6, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09B57/02
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Aqueous dye preparations contain from 12 to 30% by weight, based on the weight of the preparation and calculated as free acid, of a dye of the formula ##STR1## where L.sup.1 and L.sup.2 are each C.sub.1 -C.sub.4 -alkyl and Cat.sup..sym. is an alkali metal ion or an unsubstituted or substituted ammonium ion, and are used for coloring paper stocks.