Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Processes of preparing a desired or intentional composition...
Reexamination Certificate
2006-07-11
2006-07-11
Seidleck, James J. (Department: 1711)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Processes of preparing a desired or intentional composition...
C162S164100, C524S013000, C524S035000, C524S300000, C524S447000, C524S492000
Reexamination Certificate
active
07074845
ABSTRACT:
A novel filler treatment comprising the preparation of swollen starch-latex compositions, prepared in the presence or absence of co-additives, and the addition of the said composition to a filler suspension, has been developed. Use of the treated filler during papermaking improves filler retention and produces filled papers where addition of the filler has only a minimal negative effect on strength properties. The swollen starch-latex compositions can be prepared in a batch or jet cooker, or by mixing with hot water under controlled conditions (i.e., temperature, pH, mixing, mixing time) in order to make the starch granules swell sufficiently to improve their properties as a filler additive but avoiding excess swelling leading to their rupture. The swollen starch-latex composition is then rapidly mixed with the filler slurry, preferably in a static mixer, and added to the papermaking furnish at a point prior to the headbox of the paper machine. The starch-latex composition can be used with wood-free or wood-containing furnishes. The treated filler is easily retained in the web during papermaking, improves drainage, and gives sheets having good formation. Sheets made with the treated fillers have higher bonding and tensile strengths than sheets produced using filler treated with either swollen starch alone or latex alone. Retention and drainage are further improved when conventional retention aid chemicals are added to the furnish containing the treated filler. The use of swollen starch-latex compositions could allow the papermaker to increase the filler content of the paper without sacrificing dry strength properties or increasing the amount, and hence the cost, of the retention aid added. The combination of swollen starch and latex could be used as furnish additives in the manufacture of both filled grades and grades that contain no filler such as sack papers and paperboard products.
REFERENCES:
patent: 4104213 (1978-08-01), Chiang et al.
patent: 4277529 (1981-07-01), Friedman
patent: 4750974 (1988-06-01), Johnson
patent: 4959125 (1990-09-01), Spendel
patent: 5439558 (1995-08-01), Bergmann et al.
patent: 6117525 (2000-09-01), Trokhan et al.
patent: 6416624 (2002-07-01), Nielsen et al.
patent: 0 924 341 (1999-06-01), None
patent: WO 97/11226 (1997-03-01), None
Ogilvy Renault LLP
Pulp and Paper Research Institute of Canada
Rajguru U. K.
Seidleck James J.
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