Anthraquinone dyes and method of use
AssigneeSandoz Ltd.
InventorRoland Wald
Life of this patent
Estimating the term…
Abstract
The present invention relates to anthraquinone compounds of formula I, ##STR1## in which R.sub.1 is alkyl or cycloalkyl, R.sub.2 is hydrogen, methyl or ethyl, R.sub.3 is hydrogen or methyl, either R.sub.4 is hydrogen, methyl or ethyl, and Y--CO-- is the radical of an organic aliphatic aromatic or araliphatic carboxylic acid containing a total of 2 to 12 carbon atoms, or R.sub.4 together with the radical Y--CO-- and the nitrogen atom to which they are bound signify a cyclic imide of a dicarboxylic acid containing a total of 4 to 8 carbon atoms, X is a direct bond or (C.sub.1-3)alkylene, n is 0 or 1 which compounds are useful as colorants. More particularly those compounds where n is 1 are useful as anionic dyestuffs and those compounds where n is 0 are useful as pigments.
Claims20
A compound of formula I, ##STR67## in which R.sub.1 is alkyl or cycloalkyl,
- R.sub.2 is hydrogen, methyl or ethyl,
- R.sub.3 is hydrogen or methyl,
- R.sub.4 is hydrogen, methyl or ethyl, and Y--CO-- is the radical of an organic aliphatic aromatic or araliphatic carboxylic acid containing a total of 2 to 12 carbon atoms,
- X is a direct bond or (C.sub.1-3)alkylene,
- n is 0 or 1
- which compound, where n is 1, is in free acid or salt form.
Dependencies are inferred from the claim text.