Process for manufacturing a flushable fibrous sheet material for use in sanitary products

Claim 1

A PROCESS FOR PRODUCING A CELLULOSIC SHEET SUITABLE FOR USE IN FLUSHABLE SANITARY PRODUCTS AND BEING RESISTANT TO DISINTEGRATION IN USE, AND IN WHICH THE SHEET IS FORMED ON THE MACHINE WIRE OF A PAPER MACHINE, COMPRISING INCORPORATING IN THE WHITE WATER SYSTEM OF THE PAPER MACHINE A HIGH MOLECULAR WEIGHT WATER SOLUBLE POLYMERIC MATERIAL IN FINELY GROUND PARTICULATE FORM WHICH HYDRATES AND SWELLS RAPIDLY IN COLD WATER AND WHICH HAS COLD WATER SOLUBLE COMPONEENTS, SAID POLYMERIC MATERIAL BEING SUFFICIENTLY FINELY GROUND TO PASS THROUGH A 50 MESH SCREEN, PERMITTING SAID POLYMERIC MATERIAL TO REMAIN IN THE WHITE WATER FOR ABOUT THREE TO 90 SECONDS TO EFFECT HYDRATION AND SWELLING OF THE POLYMERIC PARTICLES BUT AVOIDING AN EXCESSIVE RESIDENCE TIME IN THE WHITE WATER SUFFICIENT TO DISSOLVE THE WATER SOLUBLE POLYMER COMPONENTS OR PERMIT LOSS OF THE HYDRATE PARTICLES THROUGH THE PAPER MACHINE WIRE, FORMING ON THE PAPER MACHINE WIRE A CELLULOSIC FIBER SHEET CONTAINING THE SWOLLEN POLYMERIC PARTICLES, AND SUBSEQUENTLY DRYING THE CELLULOSIIC SHEET PRODUCED ON THE PAPER MACHINE WITH THE WATER SOLUBLE POLYMERIC PARTICLES CONTAINED THEREIN EFFECTING BONDING TOGETHER OF THE CELLULOSIC FIBERS IN A SUFFICIENTLY STRONG MANNER TO PREVENT BREAKING OF THE BOND THROUGH NORMAL USE IN THE SANITARY PRODUCTS, BUT PERMITTING FLUSHING OF THE SANITARY PRODUCTS AFTER USE BY DISPERSING THE POLYMERIC PARTICLES AND THE CELLULOSIC FIBERS IN THE FLUSHING WATER.