Non-woven fabric treatment

This invention relates to a method of treating a non-woven fabric and to a treated non-woven fabric. The fabric can be used as a separator in an electrochemical device. Non-woven fabrics are disclosed comprising substantially unbonded fibers and vinyl monomers which are capable of reacting with an acid or a base to form a salt directly or indirectly by a reaction involving exposure to ultraviolet radiation while impregnated with a solution of the vinyl monomer copolymerized to the surface of the fibers. Laminates of these non-woven fabrics as well as electrochemical devices employing them as a separator, and methods of treating such non-woven fabrics are also disclosed.