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:
Aug. 27, 2002
Filed:
Sep. 05, 2000
Jonathan George, Vienne, FR;
Andrea Grosso, Turin, IT;
Raimo Piittala, Tampere, FI;
Kay Rokman, Karhula, FI;
Kaj Back, Tampere, FI;
Ahlstrom Paper Group Research and Competence Center, Pont-Eveque, FR;
Abstract
A non-woven web of fibrous material containing a reactive particulate material is made using the wet laid, or preferably foam, process. First and second fibrous webs are made using the wet laid or foam process, and a liquid or foam slurry including reactive particulate material is provided between the webs so as to provide a composite web. Liquid, or foam and liquid, are withdrawn from the composite web and then the composite web is dried so as to produce a final non-woven web with reactive material having substantially optimum reactivity (that is the reactive material loses a minimum amount reactivity during the web production process). The webs and slurry may be made using substantially pure water, and the particulate part of the reactive material is mixed with the foam or liquid slurry no more than about ten seconds before the liquid and/or foam are withdrawn from the composite web. Activated carbon and titanium dioxide are two particularly desirable reactive particulates; the reactive loading is at least 0.01 g/cm , and the air permeability of the final web is at least 3000 liters per square meter per second.