SEPARATION MEMBRANE

To provide a separation membrane which prevents clogging and can obtain a permeation liquid having excellent flavor.SOLUTION: A separation membrane has a layer having a spherical structure, wherein the spherical structure contains a polyvinylidene fluoride-based resin, a thickness L of the layer is 60 μm or more and 500 μm or less, the layer has a first surface and a second surface, an existential quantity Pmax/Pmin of a region Spmax with a maximum existential quantity of a polysaccharide component to a region Spmin with a minimum existential quantity thereof in a polysaccharide closed state obtained by a polysaccharide closed test in the regions partitioned with a width of 5 μm in a film thickness direction is 100.8 or more and 102.5 or less, seven or more regions with a width of 5 μm exist between the Spmax and the Spmin, and the Spmax is a region close to the first surface than the Spmin.SELECTED DRAWING: None 【課題】目詰まりが発生しにくく、しかも優れた香味を持つ透過液を得ることのできる分離膜を提供する。【解決手段】球状構造を有する層を備える分離膜であって、前記球状構造がポリフッ化ビニリデン系樹脂を含有し、前記層の厚みＬが６０μｍ以上５００μｍ以下であり、前記層が第１の面と第２の面とを有し、膜厚方向に５μｍ幅で区切られた領域のうち、多糖閉塞試験で得られた多糖閉塞状態における多糖成分の存在量が最大の領域Ｓｐｍａｘと最小の領域Ｓｐｍｉｎにおける多糖成分の存在量比Ｐｍａｘ／Ｐｍｉｎが１００．８以上１０２．５以下であり、ＳｐｍａｘとＳｐｍｉｎの間に前記５μｍ幅の領域が７つ以上存在し、かつＳｐｍａｘがＳｐｍｉｎより第１面に近い領域である分離膜。【選択図】なし