Process of improving the wet strength and dimensional stability of cellulose paper fibers and regenerated cellulose films by reacting them with acetals and products produced thereby

Claim 1

THE PROCESS OF IMPROVING THE WET STRENGTH AND DIMENSIONAL STABILITY OF CELLULOSE PAPER FIBERS AND REGENERATED CELLULOSE FILMS WHICH COMPRISES APPLYING TO SAID CELLULOSE MATERIALS AN AQUEOUS BATH CONTAINING AN ACID CATALYST AND, AS THE ESSENTIAL AGENT, AN ACETAL OF AN ALDEHYDE SELECTED FROM THE GORUP CONSISTING OF ALIPHATIC AND CARBOCYCLIC ALDEHYDES HAVING 1 TO 8 CARBON ATOMS IN MONOMERIC FORM AND MIXTURES OF THE AFORESAID ALDEHYDES, AND AN ALIPHATIC HYDROXYL-BEARING COMPOUND SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC MONOHYDRIC ALCOHOLS CONTAINING FROM 1 TO 5 CARBON ATOMS, MONOALKYLENE AND POLYALKYLENE GLYCOLS IN WHICH THE ALKYLENE RADICAL HAS FROM 2 TO 4 CARBONS ATOMS IN A STRAINGT CHAIN, AND ALIPHATIC POLYHYDRIC ALCOHOLS CONTAINING FROM 3 TO 6 HYDROXYL GROUPS AND FROM 3 TO 10 CARBON ATOMS AND MIXTURES OF THE AFORESAID HYDROXYL-BEARING COMPOUNDS, SAID ACETAL BEING APPLIED IN AMOUNT FROM ABOUT 0.02% TO ABOUT 15% BY WEIGHT OF THE DRY CELLULOSE, SAID CATALYST BEING PRESENT IN THE BATH AT LEASDT IN AMOUNT FROM ABOUT 10% TO ABOUT 285% BASED ON THE WEIGHT OF THE ACETAL AND HEATING THE CELLULOSE MATERIALS AT ELEVATED TEMPERATURE UNTIL THE ACETAL REACTS WITH THE CELLULOSE AND IMPROVES THE WET STRENGHT AND DIMENSIONAL STABILITY OF THE CELLULOSE.