| abstract |
COATED PAPER IS PROVIDED IN SHEET, ROLL OR OTHER PHYSICAL FORM AND SHAPE WHICH IS WATER-REPELLENT WHEN WETTED ON EITHER SIDE BUT WHICH READILY DISINTEGRATES WHEN BOTH SIDES ARE WETTED AS WHEN THE ENTIRE SHEET IS IMMERSED IN WATER. THE PAPER IS PREFERABLY OF TOILET OR FACIAL TISSUE QUALITY OR WATER-SOLUBLE OR ANY OTHER TYPE, PROVIDED IT IS NOT WETSTRENGTH GRADE, WHICH READILY DISINTEGRATES IN WATER. A WATER-SOLUBLE GRADE OF NON-WOVEN FABRIC MAY ALSO BE USED INSTEAD OF PAPER. THE PAPER IS FIRST COVERED WITH AN EXTREMELY THIN (2 TO ABOUT 5 POUNDS PER REAM) COATING WHICH DOES NOT APPRECIABLY PENETRATE INTO OR IMPREGNATE THE PAPER. THE COATING IS PREFERABLY AN EXTREMELY THIN LAYER OF POLYETHYLENE WHICH SERVES AS A HOLD-OUT COATING FOR A SUBSEQUENT WATER-REPELLENT COATING, PREFERABLY OF WAX, MODIFIED WITH ETHYL VINYL ACETATE OR SYNTHETIC RUBBERS AND SOFTENERS. BY FLASHING THE POLYETHYLENE OR OTHER POLYMER HOLD-OUT LAYER WITH HEAT PRIOR TO APPLICATION OF THE WAX COATING OR BY APPLYING THE MODIFIED WAT AT TEMPERATURES IN THE RANGE OF 185* TO 235*F. (DEPENDING ON THE SPEED OF THE WAX COATING OPERATION) THE STRETCH PROPERTIES OF THE POLYETHYLENE ARE TOTALLY ELIMINATED AND YET THE POLYETHYLENE SERVES AS A HOLD-OUT COATING FOR THE FLEXIBLE WAX LAYER AND PREVENTS IS FROM SINKING INTO THE TISSUE PAPER AND RENDERING IT WATER-INSOLUBLE AND WITH WET STRENGTH PROPERTIES. WHEN AN ADDITIONAL UNCOATED SHEET OF TISSUE PAPER IS PLACED ON TOP OF TH WAXY INSOLUBLE COATING THE RESULT IS A SHEET WHICH REPELS WATER AS WELL AS THE PASSAGE OF BACTERIA AND OTHER MICRO-ORGANISMS ON EITHER SIDE AND MANITAINS ITS STRENGTH BUT WHICH, WHEN WETTED ON BOTH SIDES, READILY DISINTEGRATES OR DISSOLVES MUCH LIKE AN UNCOATED SHEETOF TISSUE PAPER. WHEN WETTED ON ONE SIDE THE SHEET DERIVES ITS STRENGTH FROM THE BOTTOM LAYER OF PAPER WHICH IS KEPT DRY AND STRONG BY THE WATERREPELLENT COATING. THE COATING, ITSELF, WHILE FLEXIBLE AND VIRTUALLY PIN-HOLE FREE, HAS NO STRETCH PRPERTIES AND IS VERY WEAK. WHEN BOTH TOP AND BOTTOM LAYERS OF PAPER ARE WETTED (AS WHEN FLUSHED ON A TOILET) THE ENTIRE SHEET TEARS AND DISINTEGRATES READILY SINCE THERE REMAINS NOTHING TO SUPPORT THE THIN, WHEAK WATER-INSOLUBLE COATING. THE SHEET MATERIAL IS ADAPTED FOR A VARIETY OF USES IN THE HOSPITAL, SANITARY, NURSING HOME AND CONSUMER FIELDS AND MAY BE CUT OR SHAPED INTO SIZES AND CONFIGURATIONS SUITABLE FOR THE PARTICULAR INTENDED USE. |