Patent ID: 6270627
Filing Date: 2001-08-07
Classification: C01B,D21H

Abstract:
A method for the manufacture of a cellulosic sheet which comprises:a. forming a cellulosic furnish containing from 0.01 to 1.5% by weight cellulosic fiber,b. adding to the furnish:(i) from about 0.00005 to about 1.25% by weight, based on the dry weight of fiber in the furnish, of a borosilicate having a mole ratio of boron to silicon of from about 1:1000 to about 100:1, a mole ratio of alkali metal to silicon of from about 6:1000 to about 1.04:1, a particle size of from about 1 to 2000 nm; and a surface area of from about 15 to 3000 m.sup.2 /g.; and,from about 0.001 to about 0.5% by weight, based on the dry weight of fiber in the furnish of a substantially water soluble polymeric flocculant having a molecular weight greater than 500,000 daltons; and then,c. dewatering said furnish to obtain a cellulosic sheet.