Patent ID: 6579415
Filing Date: 2003-06-17
Classification: D06M,D21C,D21H

Abstract:
A method for increasing the wet strength of a fibrous sheet, comprising:forming a fibrous slurry, wherein the slurry comprises individualized carboxylated cellulosic fibers, the fibers comprising cellulosic fibers covalently coupled to a carboxylating agent through an ester bond, wherein the carboxylating agent provides a carboxyl group to the fibers, and wherein the carboxylating agent is a polycarboxylic acid having one carboxyl group separated from a second carboxyl group by either two or three atoms, wherein the carboxylated fibers have a water retention value greater than or equal to the water retention value of the fibers from which the carboxylated fibers are formed; depositing the fibrous slurry on a foraminous support; dewatering the deposited slurry to provide a wet composite; and drying the wet composite to provide a fibrous sheet having a wet strength greater than a fibrous sheet formed from a fibrous slurry lacking carboxylated cellulosic fibers.