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US 5,554,731 AGranted
Process for the preparation of aminoazo dyes
AssigneeBayer Aktiengesellschaft
InventorsKarl-Josef Herd, Peter Roschger
Life of this patent
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Abstract
Preparation of water-soluble reactive dyes containing vinylsulphonyl and .beta.-sulphatoethylsulphonyl groups by the oxidation of dyes containing .beta.-hydroxyethylmercapto radicals, and then sulphation and, if appropriate, conversion of the .beta.-sulphatoethylsulphonyl radical to the vinylsulphonyl radical with bases.
Claims2
A process for the preparation of a water-soluble reactive dye of structure (1):
- A--(SO.sub.2 X).sub.1 or 2 ( 1)
- wherein
- A is a chromophoric azo, polyazo, anthraquinone or formazane radical, and
- X is a CH=CH.sub.2 or CH.sub.2 CH.sub.2 OSO.sub.3 H,
- which comprises oxidizing a mercapto compound of the formula
- A--(S--CH.sub.2 --CH.sub.2 --OH ).sub.1 or 2
- to form a sulphonyl compound of the formula
- A--(SO.sub.2 --CH.sub.2 --CH.sub.2 --OH).sub.1 or 2,
- sulphating said compound to produce a sulphate of the formula
- A--(SO.sub.2 --CH.sub.2 --CH.sub.2 --OSO.sub.3 H).sub.1 or 2,
- or further reacting said compound with a base to produce a vinylsulphonyl compound of the formula
- A--(SO.sub.2 --CH=CH.sub.2).sub.1 or 2.
9 more elements
Dependencies are inferred from the claim text.