| 摘要 |
PURPOSE:To obtain a hydraulic cylinder of a resin that has an excellent and uniform surface smoothness, by incorporating a specified amount of a specified copolymerized nylon into a polyamide molding material in which a specified amount of an inorganic fiber has been added, and injection molding the mixture. CONSTITUTION:15 to 60wt% inorganic fiber such as glass fiber are added to a polyamide resin such as nylon 66 or the like to obtain a polyamide molding material, then 2 to 15wt% 6, 66 copolymerized nylon, 6, 610 copolymerized nylon or 6, 66, 610 terpolymerized nylon are incorporated into the polyamide molding material, and the mixture is injection molded. Thus, when the melted resin material is forced through a gate 10 and a cylinder bottom wall section 11 into a cylinder opening section 12 and a reservoir 13, an enough injection pressure can be exerted to the resin material due to the solidification delay effect of the copolymerized nylon and therefore shortage of the cavity pressure can be obviated. |
