Production of amide containing cellulose

Claim 1

IN A PROCESS OF CARBAMYLETHYLATING CELLULOSE BY HEATING IT WITH AN AQUEOUS TREATING LIQUOR COMPRISING WATER, AN ARCYLAMIDE AND A STRONG ALKALI, THE IMPROVEMENT WHICH COMPRISES; CARRYING OUT THE REACTION AT FROM ABOUT 45* TO ABOUT 130* C; MAINTAINING IN SAID TREATING LIQUOR, PER HUNDRED PARTS OF WATER, AN AMOUNT OF ALKALI STOICHIOMETRICALLY EQUIVALENT TO FROM ABOUT ONE-HALF TO ABOUT FOUR PARTS OF SODIUM HYDROXIDE, AN AMOUNT OF AN ACRYLAMIDE OF FROM ABOUT FIVE PARTS TO ABOUT THE SOLUBILITY LIMIT AT THE OPERATING TEMPERATURE, AND AN AMOUNT EFFECTIVE TO PRODUCE SWELLING OF THE CELLULOSE OF A WATERSOLUBLE SALT OF A STRONG ALKALI AND A STRONG ACID, SAID SALT HAVING IN WATER ALONE A SUBSTANTIALLY NEUTRAL TO SLIGHTLY ALKALINE PH AND BEING IN SAID TREATING LIQUOR SUBSTANTIALLY UNREACTIVE WITH THE ARCYLAMIDE; MAINTAINING SAID CELLULOSE IN INTIMATE REACTIVE CONTACT WITH A SUFFICIENT AMOUNT OF SAID TREATING LIQUOR TO THROUGHLY WET THE CELLULOSE; AND MAINTAINING SAID CONDITIONS UNTIL SUBSTITUTION IS COMPLETED, WHEREBY THE AMIDE-CONTAINING CELLULOSE IS OBTAINED WITH A MINIMIZED CARBOXYETHYL CONTENT.