Filter material
CA 2136563 C · Owner: Heinrich, Gunter · Inventors: Heinrich, Gunter; Kochel, Roland
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention concerns a filter material particularly useful in the manufacture of tea bags coffee, bags, coffee filters and the like. The filter material includes an at least two layer non-woven substrate material wherein the two layers are essentially planar and super-imposed one layer is composed of natural fibers and one layer is composed of synthetic fibers. The synthetic fiber layer includes a plurality of individual plastic fibers which are deposited in a heated state on the natural fiber layer. The plastic fibers fuse with each other and also fuse with the natural fibers of the other layer. The filter material provides the particular advantage due to the, deposition of the …
Read the whole patent
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 November 24, 1994 and granted July 13, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 24, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 24, 2016.
- 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
Timeline From CIPO dates
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.