Process for preparing a bulky synthetic pulp sheet useful as a separator for sealed-type lead batteries.

摘要

A separator for electrical cells is obtained using a bulky synthetic pulp sheet. A bulky synthetic pulp sheet is provided, which comprises 50 to 95% by weight of a synthetic pulp having a drainage factor over a range of from 0.1 to 2.0 sec/g and 5 to 50 % by weight of a polymer binder having a melting point lower than the melting point or decomposition temperature of the synthetic pulp; the sheet has an apparent density of 0.15 g/cm<3> or less under a load of 200 g/cm<2>. A process for the preparation of the bulky synthetic pulp sheet is also provided, comprising subjecting a mixture of the synthetic pulp and the fibrous binder to wet-type sheet-making and heat treatment.