BATTERY SEPARATOR OF OLEFINIC-FLASH SPUN FIBERS

摘要

A battery separator of reduced electric resistance comprising a self-supporting non-woven mat consisting essentially of a mixture of (A) olefinic resin fibers having a coarseness of from 4 to 13 decigrex, (B) olefinic resin fibers having a coarseness of less than 4 decigrex in an amount of not less than 3 parts by weight per 100 parts by weight of fibers (A) and (C) inert filler materials in an amount of 0 to about 600 parts by weight per 100 parts by weight in total fibers (A) and (B). The battery separator is produced by subjecting an aqueous dispersion of said mixture to a sheet-forming operation; drying the resulting wet non-woven mat; and heattreating the dried mat at a temperature ranging from a point 20.degree.C lower than the melting point of the fibers (A) and (B) to a point about 50.degree.C higher than the melting point.