Breathable fabric with a layer of water-sweliable elastomer

Claim 1

A BREATHABLE FABRIC PARTICURLARLY USEFUL AS RAINWEAR WHICH, IN CONTACT WITH LIQUID WATER IS WATER IMPERMEABLE BUT OUT OF CONTACT WITH LIQUID WATER, IS AIR AND WATER VAPOR-PERMEABLE, WHICH COMPRISES A FIBROUS TEXTILE FABRIC HAVING DEPOSITED BELOW ONE SURFACE OF BUT ABOVE THE MIDPLANE OF SAID FABRIC A LAYER OF WATER-SWELLABLE ELASTOMER HAVING AN ELONGATION OF AT LEAST 200% IN THE DRY STATE, WHICH LAYER, OUT OF CONTACT WITH LIQUID WATER, IS DISCONTINUOUS AND POROUS BY VIRTUE OF THE PRESENCE THEREIN OF A PLURALITY OF MINUTE VOIDS WHICH PERMIT PASSAGE THERETHROUGH OF AIR AND OF WATER VAPOR, AS SUCH, BUT WHICH ELASTOMER LAYER, IN CONTACT WITH LIQUID WATER, SWELLS FROM 50-500% OF THE VOLUME THE ELASTOMER HAS OUT OF CONTACT WITH LIQUID WATER, THEREBY SUBSTANTIALLY AND IMMEDIATELY TO REDUCE THE CROSS-SECTIONAL AREA OR SIZE OF SAID VOIDS TO SUCH AN EXTENT AS TO PRECLUDE THE PASSAGE OF LIQUID WATER, AS SUCH, THROUGH SAID VOIDS AND THUS TO REMAIN IMPERVIOUS TO THE PENETRATION OF WATER FOR SO LONG A TIME AS LIQUID WATER IS IN CONTACT WITH SAID LAYER BUT WHICH, UPON REMOVAL OF LIQUID WATER FROM CONTACT WITH SAID LAYER, SHRINKS AND THEREBY REGAINS ITS ORIGINAL DISCONTINUITY AD POROSITY AND ITS ORIGINAL PERMEABILITY TO AIR AND WATER VAPOR.