Abstract:
A process for the preparation of stable polyurethane urea solutions by chain lengthening with bifunctional hydrazide compounds prepolymers prepared from dihydroxy compounds and excess 1-isocyanato-3-isocyanato-methyl-3,5,5trimethylcyclohexane. The polyurethane ureas dissolved in a mixture of water, aromatic hydrocarbons and aliphatic alcohols can be used for producing coatings which have exceptional light fastness.
Abstract:
COATED SUBSTRATES ARE PREPARED BY A PROCESS WHICH COMPRISES TREATING A SUBSTRATE MATERIAL WITH A CURABLE COATING COMPOSITION COMPRISING (A) A KETOXIME BLOCKED ISOCYANATE TERMIANTED REACTION PRODUCT OF A POLYOL WITH AN ISOCYANURATE POLYISOCYANATE, SAID REACTION PRODUCT HAVING A MOLECULAR WEIGHT OF FROM ABOUT 8,000 TO ABOUT 15,000, (B) A TERTIARY AMINOALCOHOL HAVING AT LEAST TWO HYDROXYL GROUP, OPITIONALLY IN THE PRESENCE OF (C) AN INERT ORGANIC SOLVENT, AND HEATING THE COATED SUBSTRATE MATERIAL TO TEMPERATURES OF FROM ABOUT 80*C. TO ABOUT 200*C. TO CROSSLINK THE CURABLE COATING COMPOSITION.