| 摘要 |
PURPOSE:To obtain a high performance flexible hose excellent in high pressure resistance, low expansibility, heat resistance, hot water resistance and fatigue resistance by using a specific PVA fiber as a reinforcing material. CONSTITUTION:An oil brake hose has a two-layer structure in order to secure safety even when one layer is destructed. Since the inner layer braid system being the first layer largely contributes to the capacity of the hose, a high performance PVA fiber is pref. used at least in the first layer. By using the high performance fiber formed from a specific PVA polymer as a reinforcing material, the difficult point of hot water resistance from the aspect of the process at the time of the manufacturing of the hose is reduced and, further, the capacity of the hose can be also enhanced. As properties to be equipped, tensile strength is 15g/d or more, the initial modulus of elasticity is 250g/d or more, the strength retentivity of the fiber due to hot water of 120 deg.C after constant length heat treatment is 80% or more and the polymerization degree of PVA is 3,000 or more. |
