abstract |
A process for coloring polyurethane resins made by a polyaddition reaction of a polyol and an isocyanate is provided, which comprises adding to the reaction mixture before or during the polyaddition reaction a reactive coloring agent suitable for incorporation in the resin with the formation of covalent bonds, said coloring agent having the formula: ##STR1## in which R 1 and R 2 are independently selected from an alkyl group having from 1 to about 12 carbon atoms, X is --CH 2 --, a and a' are integers from 1 to about 6, and Y and Y' are independently selected from polymeric units of hydroxy alkylenes or alkylene oxide monomers selected from ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, or glycidol, b and b' are independently either 0 or 1, and Z and Z' are reactive groups independently selected from --OH, --NH 2 , or --SH. |