| 摘要 |
PROBLEM TO BE SOLVED: To provide a resin mandrel for a hose which has excellent durability, and can produce a rubber hose at high dimensional precision. SOLUTION: Since the water absorption coefficient of a thermoplastic resin forming a resin mandrel 1 is controlled to≤0.05%, even in an environment where heating steam is filled upon vulcanizing, water is made hard to be absorbed, and, even when it is repeatedly used in the production process, deterioration such as production of fine chips at an early stage can be prevented, and since its linear expansion coefficient is controlled to≤6.0×10<SP>-5</SP>/K, expansion/shrinkage caused by a temperature change due to heating upon vulcanizing is reduced, and the rubber hose can be produced while suppressing an adverse influence on the dimensional precision of the rubber hose. Since the bending strength is controlled to 40 to 120 MPa, the mandrel is not broken even when being repeatedly used in a bent form, and its bending rigidity suitable for handling can be secured. COPYRIGHT: (C)2009,JPO&INPIT |
