| 摘要 |
PURPOSE: To provide a coating agent for motor car glass run which contains a terminal OH-containing urethane prepolymer, a silicone oil, a hydrophobic silica and a terminal NCO-containing polyisocyanate, thus avoids occurrence of defects in appearance and has improved abrasion resistance after coating. CONSTITUTION: This coating agent comprises (A) 100 pts.wt. terminal OH- bearing urethane prepolymer, (B) 1-200 pts.wt. silicone oil (preferably dimethylsilicone oil), (C) 1-50 pts.wt. hydrophobic silica (preferably fine particles of silica is made hydrophobic by surface treatment) and (D) 10-200 pts.wt. terminal NCO-bearing polyisocyanate as a curing agent. The component A is preferably prepared by reaction of a terminal OH-bearing polyester from a 3-6C saturated lower diol, a 4-6C organic dicarboxylic acid and less than 1wt.%, based on the total dicarboxylic acid, three-functional lower polyol, with a diisocyanate at a molar ratio of NCO:OH=(0.6-0.95):1. |
