The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 22, 2001
Filed:
Mar. 18, 1999
Applicant:
Inventors:
Steven R. Middleton, Pointe Claire, CA;
Josée Desmeules, Montreal, CA;
Anthony M. Scallan, Pointe Claire, CA;
Assignee:
Pulp and Paper Research Institute of Canada, Pointe Claire, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21H 1/767 ;
U.S. Cl.
CPC ...
D21H 1/767 ;
Abstract
A method is described for attaining high levels of loading of calcium carbonate fillers in the lumens of wood pulp fibers. The pulp is pretreated with a cationic polymer prior to being impregnated with the filler. Different conditions of pH and temperature are specified depending on whether the filler is a precipitated calcium carbonate or a ground calcium carbonate. The lumen-loaded pulps are used to make novel products with advantages in higher filler retention and sheet strength over conventionally made papers.