HOLLOW POROUS FILM AND METHOD FOR PRODUCING THE SAME

• Main Authors: HINENOYA MITSURU, TAKAHASHI SHUSAKU, TERAMACHI MASASHI
• Format: Patent
• Language: English; Japanese
• Published: 14.02.2019
• Subjects: LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

To provide a hollow porous film which can achieve both excellent permeable performance and excellent fraction performance over a long period of time.SOLUTION: A hollow porous film 1 has a film layer formed of polyvinylidene fluoride, where a mass average molecular weight (Mw) of the polyvinylidene fluoride is 2.0×10or more and 1.2×10or less, the polyvinylidene fluoride has a ratio (Mw/Mn) of the mass average molecular weight (Mw) to the number average molecular weight (Mn) of 4.0 or less, and in the polyvinylidene fluoride, particles with a particle diameter of 0.022 μm or more are 1.2×10pieces/cmor less in an N,N-dimethyl acetamide solution obtained by dissolving polyvinylidene fluoride in N,N-dimethyl acetamide so that a content of the polyvinylidene fluoride is 5 mass%.SELECTED DRAWING: Figure 1 【課題】長期にわたって、優れた透水性能と優れた分画性能とを両立できる中空状多孔質膜を提供する。【解決手段】ポリフッ化ビニリデンからなる膜層を有する中空状多孔質膜１であって、前記ポリフッ化ビニリデンの質量平均分子量（Ｍｗ）が２．０×１０５以上、１．２×１０６以下であり、前記ポリフッ化ビニリデンは、質量平均分子量（Ｍｗ）と数平均分子量（Ｍｎ）の比（Ｍｗ／Ｍｎ）が４．０以下であり、前記ポリフッ化ビニリデンは、ポリフッ化ビニリデンの含有量が５質量％となるようにポリフッ化ビニリデンをＮ，Ｎ−ジメチルアセトアミドに溶かして得られるＮ，Ｎ−ジメチルアセトアミド溶液中の、粒径０．０２２μｍ以上の粒子が１．２×１０１６個／ｃｍ３以下となるポリフッ化ビニリデンである。【選択図】図１