| abstract |
1278312 Azo dyes CIBA-GEIGY AG 9 July 1969 [15 July 1968] 34592/69 Heading C4P New azo dyes containing at least one acidic group which imparts solubility in water, not in a vicinal position to the azo bridge, and a residue of formula are prepared by azo coupling using 2,6- dihydroxy - 3 - cyano - 4 - methyl - pyridine as coupling components. The preferred dyes contain fibre-reactive groups which are present in the diazo component or subsequently introduced into the dye by a condensation reaction. The preparation of mono- and dis-azo, metallized azo and phthalocyanine-azo dyes which dye cellulose and wool fibres in yellow, red, green and brown shades is described in examples. |