PURPOSE: To perform easy manufacture with high processing precision at a low cost by a method wherein a heating fluid flow passage part having a panel and a hollow part, through which heating fluid flows, is an integral molded product injection-molded by using thermoplastic resin.
CONSTITUTION: A panel 12 for preventing freezing of the wiper of a vehicle and a heating fluid flow passage part 14 having a hollow part through which heating fluid flows are an integral molded prod which is injection-molded by using thermoplastic resin. In this case, the heating fluid flow passage 14 is integrally molded such that a pre-molded panel 12 is placed in a mold cavity, and molten thermoplastic resin is injected in the mold cavity and thereafter, pressure gas is injected in molten thermoplastic resin to form a hollow part 16.
KOYAMA AKIRA
NISHIO NAOTO
