Method of producing resinous copolymers in situ on fabrics

Claim 1

IN THE ART OF IMPARTING DURABLE MECHANICAL FINISHES TO CELLULOSIC FABRICS INVOLVING IMPREGNATING THE FABRIC WITH AN AQUEOUS SOLUTION CONTAINING A MIXTURE OF RESINOUS FINISHING AGENTS TO BE RETAINED BY THE FABRIC WHEREIN SAID RESINOUS MIXTURE INCLUDES A WATER-SOLUBLE THERMOSETTING RESIN PRECONDENSATE AS ONE RESINOUS COMPONENT AND POLYVINYL ALCOHOL AS A SECOND RESINOUS COMPONENT DRYING THE FABRIC, CALENDERING THE DRIED IMPREGNATED FABRIC AND HEATING THE FABRIC IN THE PRESENCE OF A RESIN CURING CATALYST TO FIX THE RESINOUS FINISHING AGENTS, THE IMPROVEMENT CHARACTERIZED IN THAT THE POLYVINYL ALCOHOL IS AT LEAST 50% HYDROLYZED, THE WATER-SOLUBLE THERMOSETTING RESIN PRECONDENSATE IS SELECTED FROM THE GROUP CONSISTING OF METHYLOL UREAS, METHYLOL MELAMINES, AND KETONE ALDEHYDES, THE WEIGHT RATIO OF THE POLYVINYL ALCOHOL TO THE THERMOSETTING RESIN PRECONDENSATE RANGES FROM 1:3 TO 1:125, THE TOTAL COMBINED WEIGHT OF THE POLYVINYL ALCOHOL AND THE THERMOSETTING RESIN COMPRISES AT LEAST 90% OF THE INTER-REACTABLE MATERIALS PRESENT IN THE IMPREGNATING SOLUTION, AND COMPRISES THE MAJOR PORTION OF THE FINISHING AGENTS TO BE RETAINED BY THE FABRIC, THE TOTAL RESIN CONCENTRATION OF THE IMPREGNATING SOLUTION AND THE SOLUTION PICK-UP ARE ADJUSTED TO PROVIDE FOR APPLYING TO THE FABRIC A TOTAL COMBINED WEIGHT OF THE RESIN SOLIDS OF FROM 2 TO 8% OF THE WEIGHT OF THE FABRIC AND THE HEATING OF THE FABRIC IS SUFFICIENT TO EFFECT THE FORMATION OF A WATER INSOLUBLE COPOLYMER OF POLYVINYL ALCOHOL AND THE THERMOSETTING RESIN.