Abstract: A process for diazotizing an amine comprises the steps of oxidizing nitric oxide in solution with an oxidizing agent to maintain an equilibrium concentration of a diazotizing agent and reacting a primary aromatic amine in situ with said diazotizing agent in said solution.

Abstract: A trichromatic dye combination especially suited for the continuous dyeing of synthetic polyamide materials; the system including an acid red dye component, an acid blue dye component and an acid yellow dye component, each of said dye components being selected on the basis of minimum and compatible cold strike and compatible on tone strike rates.The trichromatic combination according to the invention dyes synthetic polyamide fibers from aqueous liquors, producing level dyeings having excellent fastness properties including good lightfastness and good ozone fastness.

Abstract: The specification describes a new group of alkanol substituted disazo compounds that are useful in dyeing polyamide textile fibers in orange hues. The new compounds are compatible with several acid blue dyes and several acid red dyes that are commercially important as dyes for nylon. The new compounds are particularly well suited for use as the "yellow" component in trichromatic systems for dying polyamide carpeting and other textiles. The new compounds are relatively inexpensive to make and have outstanding application and fastness properties. Other aspects of the specification are concerned with a method of making the new compounds and with a method of dyeing polyamides with said compounds and to the novel dyed polyamides resulting from the use of the new group of compounds as dyes.

Abstract: The present invention is a process for the preparation of concentrated anionic red dye solutions which are storage stable. The process allows manufacture of a solution of a dye having the formula: ##STR1## wherein R.sub.1 is --SO.sub.2 N(CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.3).sub.2, --SO.sub.2 N(C.sub.6 H.sub.5)(CH.sub.2 CH.sub.3), --SO.sub.2 N(CH.sub.3)(C.sub.6 H.sub.11), or --CF.sub.3 ;R.sub.2 is --H, --Cl or ##STR2## and R.sub.3 is lower alkyl M is ##STR3## wherein R.sub.4 and R.sub.5 are --H or --CH.sub.3 independently andm+n+q.ltoreq.9, but >0,by reacting a dye having the structure: ##STR4## wherein R.sub.1 is --SO.sub.2 N(CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.3).sub.2, --SO.sub.2 N(C.sub.6 H.sub.5)(CH.sub.2 CH.sub.3), --SO.sub.2 N(CH.sub.3)(C.sub.6 H.sub.11), or --CF.sub.3 ;R.sub.2 is --H, --Cl or ##STR5## wherein R.sub.3 is lower alkyl, andX is NH(R.sub.6).sub.3,wherein R.sub.

Abstract: A trichromatic dye system for the dyeing of synthetic polyamide fibers, the system including an acid red dye component, an acid blue dye component, and an acid yellow dye component, each of the dye components being compatible from a performance standpoint.