Sulfur containing atomic group introduced porous article, process for introducing a sulfur containing atomic group onto the outer-inner surfaces of a porous article, and a battery separator

Abstract

A porous article wherein a sulfur containing atomic group is introduced onto at least a part of outer-inner surfaces of the article, a ratio (S/C) of the number of sulfur atoms (S) to the number of carbon atoms (C) on the surface onto which the sulfur containing atomic group is introduced is 7×10−4 or more, a ratio (O/C) of the number of oxygen atoms (O) to the number of carbon atoms (C) on the surface onto which the sulfur containing atomic group is introduced is 0.2 or more, and the ratio (S/C) and the ratio (O/C) are determined by means of an X-ray photoelectron spectrophotometer is disclosed.

Dependencies are inferred from the claim text.