Non-woven bonded fibrous products and methods for their production

Claim 1

A PROCESS OF MAKING A NON-WOVEN FABRIC WHICH COMPRISES ASSOCIATING, IN RANDOM ARRAY WITHIN A WEB OR MAT, A MASS OF FIBERS COMPRISING A PREDOMINANT PROPORTION OF FIBERS SELECTED FROM THE GROUP CONSISTING OF CELLULOSIC FIBERS, POLYAMIDE FIBERS, VINYL RESIN FIBERS, AND POLYESTER FIBERS, BRINGING INTO CONTACT WITH THE FIBERS A BINDER COMPRISING AN AQUEOUS DISPERSION CONTAINING (1) A WATERSOLUBLE AMINOPLAST AND (2) 2 TO 60% BY WEIGHT OF A WATER-INSOLUBLE COPOLYMER, HAVING A MOLECULAR WEIGHT FROM 100,000 TO TEN MILLION AND A T1 VALUE NOT OVER 30* C., OF 97 TO 80% BY WEIGHT OF AT LEAST ONE ESTER OF AN ALCOHOL HAVING 1 TO 18 CARBON ATOMS AND AN ACID SELECTED FROM THE GROUP CONSISTING OF ACRYLIC ACID AND METHACRYLIC ACID WITH 3 TO 20% BY WEIGHT OF A COMPOUND SELECTED FROM THE GROUP CONSISTING OF THOSE HAVING ONE OF THE FORMULAS I AND II FOLLOWING, THE AMOUNT OF AMINOPLAST BEING FROM 2 TO 25% BY WEIGHT OF THE COPOLYMER, DRYING THE FIBROUS MASS CONTAINING THE BINDER AT A TEMPERATURE ABOVE THE T1 OF THE POLYMER TO EFFECT FUSION OF THE POLYMER AND BONDING OF THE FIBERS THEREBY, AND HEATING THE DRIED FIBROUS PRODUCT AT A TEMPERATURE OF 110*C. TO 350*C. TO RENDER THE BINDER INSOLUBLE IN ORGANIC SOLVENTS, FORMULAS I AND II BEING: