Method of making a bonded permeable article

Claim 1

IN MAKING A COATED SHEET MATERIAL THAT IS PERMEABLE TO AIR AND MOISTURE, THE METHOD WHICH COMPRISES APPLYING TO THE FACE OF A PERMEABLE SHEET A THIN FILM OF A VISCOUS AQUEOUS DISPERSION OF AN ORGANIC THICKENING AGENT IN THE PROPORTION OF 0.5 PART 5 PARTS OF THE THICKENING AGENT FOR 100 PARTS OF THE DISPERSION, THE SAID DISPERSION REMAINING ON THE FACE OF TE SHEET, THEN APPLYING DIRECTLY UPON THE SAID FILM IN WET CONDITION A FREE-FLOWING MASS OF FINE PARTICLES OF NORMALLY SOLID THERMOPLASTIC MATERIAL THAT ARE INSOLUBLE IN THE SAID DISPERSION AND ARE SOFTENABLE INDIVIDUALLY TO FLOWABLE FLUID CONDITION AT A TEMPERATURE OF 300*-400* F., REMOVING THOSE OF THE SAID PARTICLES NOT DIRECTLY IN CONTACT WITH THE SAID FILM, THIS REMOVAL DEVELOPING SPACES BETWEEN THE REMAINING THERMOPLASTIC PARTICLES, AND HEATING TH SHEET,FILM AND REMAINING SPACED THERMOPLASTIC PARTICLES TO THE TEMPERATURE OF SOFTENING OF THE SAID PARTICLES TO FLOWABLE FLUID CONDITION THIS HEATING CAUSING LOSS OF WATER AND DEVELOPMENT OF DISCONTINUITY OF THE FILM RESIDUE SO PRODUCED AND FINALLY CAUSING SOFTENING OF THE REMAINING THERMOPLASTIC PARTICLES AND PENETRATION OF THEM WITHIN THE SURFACE PORTION OF THE SAID SHEET.