Verfahren zur Herstellung neuer Farbstoffe der Anthrachinonreihe

The invention comprises dyes of the formula wherein X is hydroxyl or a primary or alkylated amino group, n is a whole number and Y is a reactive aliphatic acyl group, i.e. an aliphatic acyl group capable of reacting with a cellulosic fibre to form a covalent bond. The dyes are made by treating a dye of the formula wherein X, Y and n are as above, with a reducing agent is a slightly acid to alkaline bath to split off the sulphonic acid group in the 2-position, and if necessary oxidizing the dyestuff, or by acylating a dye of the formula with an anhydride or halide of an aliphatic acid, the aliphatic chain of which contains a grouping capable of reacting with cellulose fibre to form a covalent bond. Those dyes in which Y is an acroyl radical are also made by treating those wherein Y is b -chloropropionyl with an alkali. Specified values for Y are vinylsulphonyl, acryloyl, monochloroacryloyl, propiolyl, b -sulphatoethylsulphonyl, chloroacetyl, b -chloropropionyl, a :b -dichloropropionyl, b -sulphatopropionyl, b - methylsulphonyloxypropionyl and b -chlorocrotonyl radicals. The dyes dye and print polyamide and polyurethane fibres, silk and wool from a slightly acid, neutral or slightly alkaline bath in blue shades. Specification 885,814 is referred to.