TUBULAR MULTILAYERED BLOW MOLDED PRODUCT AND PRODUCTION THEREOF

摘要

PROBLEM TO BE SOLVED: To prevent the damage or abrasion of a bent tubular molded product at an attaching region by providing a part where the wall thickness ratio of the inner and outer layers of a pipe wall is changed along a longitudinal direction and differentiating the kind of the resin forming the inner layer from that of at least one of the resins of two demarcated regions forming the outermost layer. SOLUTION: A tubular multilayered blow molded product 6 has two demarcated regions partitioned by the boundary line 4 parallel to the outermost layer in the longitudinal direction thereof so that the setting of a resin A becomes the upper half surface of the molded product and the section of a resin B becomes the rear surface thereof. The A-resin layer on the upper half surface side is composed of a polyamide 6 resin good in glossiness and the B-resin layer on the lower half surface side of an outer layer is composed of a glass fiber reinforced polyamide layer excellent in rigidity and heat resistance. The resin C of an inner layer is composed of a polyamide 11 resin having adhesiveness to these polyamide resins, having high flexibility and strong against hydrolysis. The wall thickness ratio of the soft resin layer C arranged inside the inner layer is made high at a part where the wall thickness ratio of the inner and outer layers of a pipe wall is changed along the longitudinal direction to impart flexibility.