| 摘要 |
In a preferred embodiment, an improved high solids polyurethane paint composition contains metallic flake pigment and a binder comprising a particular isocyanate-terminated polyether-urethane resin. The resin is formed by reacting an excess of a suitable aliphatic diisocyanate with a suitable mixture of polyoxypropylene diols and triols and a hindered piperidine type UV stabilizer in the presence of an organotin catalyst. The product urethane resin having the stabilizer reacted into its molecular structure is formulated with color producing pigments, metallic flakes and a suitable solvent to produce a composition having a nonvolatiles content of 60 to 70 weight percent. The composition is spray applied to a substrate and moisture cured to provide a decorative topcoat wherein the flakes lie at varying depths and are oriented substantially parallel to the topcoat surface. The topcoat with the desired flake orientation displays a high degree of geometric metamerism comparable to metallic acrylic lacquer topcoats applied at a substantially lower solids content.
|
