Polyurethane coating materials for corrosion-proof coatings - based on poly:ol component contg. cyclo-aliphatic tri:ol, indane copolymer with phenolic hydroxyl, and tert. amino-contg. polyether-poly:ol

摘要

Polyurethane (PU) coating materials (I) are obtd. by reaction of (A) opt. modified polyisocyanates with (B) OH cpds. and opt. (C) low-mol. wt. chain-extenders and/or crosslinkers, opt. in the presence of (D) catalysts and (E) additives. (B) are mixts. of (B1) cycloaliphatic triol(s), (B2) copolymeric aromatic hydrocarbon(s) with phenolic OH gp(s). and (B3) polyether-polyol(s) with functionality at least 3, contg. at least one tert. amino gp.. Also claimed is a solvent-free PU coating system comprising polyisocyanate and polyol components, in which 100 pts. wt. of the polyol component contain 15-45 wt. (B1) with mol. wt. 50-1200, 12-20 pts. wt. (B2) with one phenolic OH and mol. wt. 700-1050, 4-20 pts. wt. tetrafunctional (B3) with mol. wt. 380-550, 0.20-50 pts. wt. (D) and 2.5-68.8 pts. wt. (E). USE/ADVANTAGE - Used as anticorrosion coating materials (claimed). (I) is a solvent-free PU coating system with very good adhesion to umprimed metal substrates; (I) is more hydrophobic and more stable to hydrolysis than prior-art PU systems, resulting in longer-lasting anticorrosion action and a longer service life (to the requirements of DIN 30667 Part 2); the components can be applied by spraying and are cheap and readily available.