| abstract |
A catalyst composition is disclosed which is suitable for catalysing the curing reaction between a blocked organic polyisocyanate and a polymer having hydroxyl groups. The invention is based on the discovery that a portion of the tin compounds conventionally employed to cure polymer compositions containing hydroxyl and isocyanate groups can be replaced by salts or chelated coordination complexes of divalent copper, zinc, nickel, iron, cobalt or vanadium without any substantial decrease in the cure rate or the solvent resistance of the coatings of the cured polymer. |