SEPARATOR FOR ALUMINUM ELECTROLYTIC CAPACITORS, AND ALUMINUM ELECTROLYTIC CAPACITOR

To provide a separator for aluminum electrolytic capacitors, which enables the increase in impregnation of a conductive polymer fluid dispersion while it is a thinned separator.SOLUTION: A separator for aluminum electrolytic capacitors is used, as an anode material in the state of being interposed between a pair of electrodes, for an aluminum electrolytic capacitor having a conductive polymer and an electrolyte solution. The separator comprises a regenerated cellulose fiber, and a non-lumber cellulose fiber, of which the thickness is 25-45 μm, the breakdown strength is 14 kV/mm or more, the length-weighted average fiber length is 1.8-3.0 mm, the percentage of fibers shorter than 0.2 mm in fiber length is 30-50%, and the percentage of fibers of 3.0 mm or longer in fiber length in a length-weighted fiber length distribution is 25-65%.SELECTED DRAWING: Figure 1 【課題】薄葉化したセパレータでありながら、導電性高分子分散液の含浸性を向上することができる、アルミニウム電解コンデンサ用セパレータを提供する。【解決手段】一対の電極の間に介在し、陰極材料として導電性高分子と電解液とを有するアルミニウム電解コンデンサに用いられ、再生セルロース繊維と非木材セルロース繊維とからなり、厚さが２５～４５μｍ、絶縁破壊の強さが１４ｋＶ／ｍｍ以上、長さ加重平均繊維長が１．８～３．０ｍｍであり、繊維長０．２ｍｍ未満の繊維の割合が３０～５０％であり、長さ加重繊維長分布における繊維長が３．０ｍｍ以上の繊維の割合が２５～６５％であるアルミニウム電解コンデンサ用セパレータを構成する。【選択図】図１