Method for preparing inorganic material-coated separator for storage batteries

摘要

A method for preparing an inorganic material-coated separator for storage batteries comprises the steps of extruding a sheet 6 of a thermoplastic synthetic resin including a polyolefinic resin as a principal component, inorganic powder and a pore-forming agent, using an extruder 1; adhering, to one side of the thermoplastic sheet 6, an inorganic sheet 4 mainly including an inorganic material to which a polyolefinic synthetic pulp, as an organic binder, is added in an amount ranging from 10 to 40% by weight on the basis of the total weight of the inorganic sheet 4 while the thermoplastic sheet 6 is still in the semi-molten state to give a laminate; then pressure-molding the laminate to unify the semi-molten sheet 6 with the inorganic sheet 4; and then cooling the unified laminate 7 to give the inorganic material-coated separator 7' and removing the pore-forming agent therefrom. $$