| 摘要 |
PROBLEM TO BE SOLVED: To provide a semipermeable membrane support that is superior in alkali resistance, strength, smoothness and adhesion with a semipermeable membrane.SOLUTION: The semipermeable membrane support is produced by heat treatment of fiber sheets containing polyolefin principal fibers and polyolefin binder fibers as fibrous components. The polyolefin binder fibers contain first core-sheath type conjugate fibers obtained by using polypropylene-based resins as core materials and low melting point polypropylene-based resins as sheath materials, and second core-sheath type conjugate fibers obtained by using polypropylene-based resins as core materials and low density polyethylene-based resins as sheath materials. The semipermeable membrane support has a smoothness of 2 seconds or more and 120 seconds or less, an air permeability of 0.2 cc/cmper second or more and 50.0 cc/cmper second or less, a tensile strength in the 5% extension of 1.0 kN/m or more, and a basis weight of 20 g/mor more. |
