| 摘要 |
PURPOSE:To strengthen the bonding state with polyurethane constituting a product main body and prevent a molded section from deteriorating its surface properties by mixing a specified substance with powder such as polyvinyl chloride constituting a molded section. CONSTITUTION:A mixture 2 composed of powder of polyvinyl chloride or thermoplastic polyurethane in which 3 - 25wt.% of phenol resin powder is filled in a mold recessed section 3a of a bottom force 3, and then polyurethane is injected into a cavity 4, while said filled mixture 2 is softened and melted to mold a bumper. Thus, hydroxyl radical-OH of phenol resin and isocyanate-NCO- of polyurethane are reacted to form urethane bonding - NHCOO- by which polyvinyl chloride or the like constituting the molded section and polyurethane constituting a bumper main body can be bonded together firmly. Also, as the mixing ratio of phenol resin is set properly, the deterioration of the surface properties of the molded section can be prevented securely. |
