Mixed filter bed composition and method of use
CA 2079820 C · Owner: Minnesota Mining And Manufacturing Company · Inventors: White, Donald H. Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A mixed filter bed composition for purifying for human consumption water containing inorganic organic and, biological contaminants is provided. The composition of the bed includes from about 40% to about 80% by weight of a carbonous sorbent, from about 5% to about 20% by weight of activated alumina, from about 5% to about 20% by weight of silica hydrogel, from about 5% to about 20% by weight of zeolite, and from about 0% to about 10% by weight of metallic components that generate metallic cations. The invention provides potable water, free of organic inorganic, and microbial contaminants. The invention also imparts the desirable filtration characteristics of traditional adsorbents, while …
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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
- Filed October 5, 1992 and granted July 28, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 5, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 5, 2014.
- 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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Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.