| 摘要 |
The invention relates to a coating composition comprising a polyurethane ABC having tertiary amine groups, and an epoxide-functional compound D, to a process for the preparation of an aqueous dispersion of a polyurethane ABC comprising a first step wherein a polyurethane prepolymer is made from diols or polyols A, multifunctional isocyanates B, and at least one tertiary amine C bearing a tertiary amino group and at least one isocyanate-reactive group selected from the group consisting of hydroxyl groups, amino groups, hydrazine groups, hydrazide groups, and mercaptane groups, a second step comprising reacting the prepolymer with a chain stopper which is monofunctional with regard to reaction thereof with isocyanates, or a chain extender which has two or more reactive groups that react with isocyanate, a third step comprising neutralising the product of the second step with an acid, and a fourth step comprising dispersing the neutralised product of the third step in water, and to a method of use of these coating compositions comprising mixing the polyurethane ABC and the epoxide functional compound D, and applying the coating compositions to substrates selected from the group consisting of metals, coated metals, plastics, glass, concrete, wood, cardboard, and leather. |
