Cyanopyridine-N-oxides and salts

摘要

Mono-, di- and tri-cyanopyridine-N-oxides (I) or their salts are used as bleach activators. The cyanopyridine-N-oxides are of formula (I); R1, R2 = 1-15 carbon (C) alkyl, cycloalkyl, aryl, 1-4 C alkoxy, primary, secondary or tertiary amino, halogen, sulfo, carboxyl, groups of the formulae -(CH2)rCOOH (CH2)r-CO3H, (CH2)r-PO3H2 or (CH2)l-OH or salt forms of the acid groups; r = 0-4; l = 1-4; x = 1-3; y, z = 0-4; x + y + z = 1-5 .