Fisher, Christen & Sabol
Dyestuff mixtures and process for dyeing polyester fiber therewith
 Mixtures of water-insoluble monoazo dyestuffs are disclosed together with the dyeing, padding or printing of polyester material therewith. The water-insoluble monoazo dyestuffs of the following general formula (A) ##SPC1## in which Y represents hydrogen, chlorine, bromine, methyl, ethyl, methoxy, ethoxy or cyano; R.sub.1 represents methoxy, ethoxy or phenoxy; R.sub.2 represents methyl or ethyl; R.sub.3 represents hydrogen, methyl, ethyl, cyanoethyl or allyl; and R.sub.4 represents methyl, ethyl, propyl, butyl, allyl or phenyl, are suitable for the production of inexpensive navy shades of good fastness to light, washing, perspiration, sublimation and heat setting; however, difficulties sometimes arise in the case of these dyestuffs. The improvement disclosed comprises overcoming said difficulties and providing new navy shades by using a mixture of at least two dyestuffs, in one of which the Y constituent above is hydrogen and in the other of which the Y constituent is replaced by constituent X which represents chlorine, bromine, methyl, ethyl, methoxy, ethoxy or cyano. 
Mitsui Toatsu Chemicals, Incorporated
D C C Y
D06P C09B C09B Y10S
inventional inventional inventional additional
Hiroshi Fumio Tetsuo Ken
Aiga Fujii Watanabe Mukai