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.

Date of Patent:
Jun. 12, 2001

Filed:

Apr. 16, 1998
Applicant:
Inventor:

Nipun Marwah, Mt. Pleasant, SC (US);

Assignee:

Westvaco Corporation, New York, NY (US);

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C 5/02 ;
U.S. Cl.
CPC ...
D21C 5/02 ;
Abstract

An improved process is disclosed for removing nonimpact inks and stickies contaminants from waste paper containing same by repulping the waste paper to form a slurry, adding a densifying agent and an agglomeration agent to the slurry, and subjecting the slurry to treatment with a conical cleaner to remove the inks/stickies. The densifying agent and agglomeration agent addition may be simultaneous or the densifying agent addition may precede agglomeration agent addition and, preferably, is conducted at ambient or greater temperature, at neutral to alkaline pH, and at a pulp consistency (below 18%). Densifying agent addition and agglomeration, followed by passing the repulped waste paper through a conical cleaner, provides improved ink removal over passing the slurry through a conical cleaner without such pre-treatment or with treatment only with densifying agent or only with agglomeration agent. Also, the process may be employed as an additional step in a conventional process for removing inks from reprographic printed papers, such as ink removal by screening, flotation, centrifugal cleaning, washing, and sedimentation with or without decantation. When the densifying agent is magnetite, the process may be employed with magnetic removal as an additional step.


Find Patent Forward Citations

Loading…