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US 6,270,627 B1Granted
Use of colloidal borosilicates in the production of paper
AssigneeNalco Chemical Company
InventorsBruce A. Keiser, James E. Whitten
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Abstract
The invention comprises a borosilicate retention aid composition and a method for improving the production of paper by addition of the borosilicate. The borosilicate may be utilized in conjunction with a high molecular weight synthetic flocculant and/or starch, with or without the addition of a cationic coagulant. The borosilicate material is preferably a colloidal borosilicate. Methods for the preparation of the borosilicate material are disclosed.
Claims17
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 m2/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.
5 more elements
Dependencies are inferred from the claim text.