| abstract |
Process for preparing stilbene azo dyesn4,4'-dinitrostilene-2,2'-disulfonic acidnand aromatic amino compounds or aminoazolesnin the presence of reducing sugarsnso that during the condensation, optionallynthereafter, feeds a mixture containing it into the reaction mixturenmoosaccharides and oligosaccharides snthe total concentration of reducing sugars 30nup to 800 g / l, expressed as glucose equivalentnfor 1 mo'l used 4,4‘-dinitrostilbene-n-2,2‘-disulfonic acid with reductionnis carried out in an aqueous alkaline medium atnpH above 9.nIt is the use of a mixture of reducing sugars fromnfood production as a reducing agentnin the preparation of said azo dyes. |