Method of bleaching chemical pulp in multiple stages
CA 1103409 A · Owner: Japan Pulp & Paper Research Institute, Inc. · Inventors: Nomura, Kenji; Kimura, Ryuichi; Yoneda, Yutaka
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
TITLE OF THE INVENTION:, METHOD OF BLEACHING CHEMICAL PULP IN MULTIPLE STAGES ABSTRACT OF THE DISCLOSURE:, Disclosed herein is an improvement in a method of bleaching a chemical pulp in multiple stages in which the, steps of treating the pulp with an ozone-containing gas and then washing the thus treated pulp are repeated successively. In this improved method an ozone-containing gas released, from the second stage of ozone-treatment and at least one stage of ozone-treatment following to the second stage is introduced into the first stage of ozone-treatment. According to this improved method a gas not substantially, containing ozone is finally released from the stages of ozone-treatment and …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted June 23, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 23, 1998.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.