Claims
- 1. A Method for increasing retention of fines and fillers on a cellulosic sheet formed from a papermaking furnish subjected to papermaking conditions comprising the steps of:adding to the papermaking furnish 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 subjecting the furnish to papermaking conditions; and recovering a cellulosic sheet, whereby the retention of fines and fillers on said sheet and the rate of drainage of liquid from said sheet is increased.
- 2. The method according to claim 1, wherein the papermaking furnish is selected from the group consisting of fine paper, board, and newsprint paper making furnishes.
- 3. The method according to claim 1, wherein the colloidal borosilicate is added after the flocculent.
- 4. The method of claim 3 wherein the furnish is subjected to a shear stage after the addition of flocculant but prior to the addition of borosilicate.
- 5. The method according to claim 1, further comprising the addition of a composition selected from a group consisting of: bentonite, talc, hectorite, kaolin and mixtures thereof.
- 6. The method according to claim 1, wherein the colloidal borosilicate is added in an amount of from about 0.005 to about 0.25% by weight based on the dry weight of fiber in the furnish.
- 7. The method according to claim 1, wherein the colloidal borosilicate is added in an amount of from about 0.005 to about 0.15% by weight based on dry weight of fiber in the furnish.
- 8. The method according to claim 1, wherein the flocculant is added in an amount of from about 0.005 to about 0.2% by weight based on dry weight of fiber in the furnish.
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
This application is a divisional of U.S. patent application Ser. No. 09/444,741, filed Nov. 22, 1999, now U.S. Pat. No. 6,270,627 B1; which is a divisional of U.S. patent application Ser. No. 08/940,888, filed Sep. 30, 1997, now abandoned.
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