| 摘要 |
PROBLEM TO BE SOLVED: To prevent the interface release between an insert material and polyurethane resin by using a phosphate treated zinc plated steel plate for the insert material for an automobile interior and exterior products. SOLUTION: A rough steel 10 is formed of a rough section 11 and a rail section 12 loading cargoes, and a zinc plated steel plate provided with phosphate treated steel metal piping as an insert material forming a core material and the periphery of the steel plate is coated with a polyurethane resin surface layer 2 and the insert material and the surface layer 2 are RIM molded integrally. The surface of the zinc plated steel plate insert material is phosphate treated to increase the surface roughness and enlarge the surface area of the insert material. As a result, the bonding area with polyurethane resin is increased to improve the bonding force between the insert material and the polyurethane resin on the surface layer 2 to a large extent. |
