Highly hygroscopic laminate
CA 2039357 C · Owner: Showa Denko K.K. · Inventors: Takuno, Masami
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A hygroscopic laminate comprises a hygroscopic layer comprising a gas permeable film, and a water-absorbing polymer and at least one humectant selected from the group consisting of acetic acid propionic acid, glycolic acid, lactic acid hydracrylic, acid, pyruvic acid and pyrrolidonecarboxylic acid and sodium, potassium, calcium and magnesium salts of these acids, which are wrapped in the gas permeable film; a porous non-water retention sheet; and a water impermeable sheet, the porous non-water retention sheet being disposed on one side of the hygroscopic layer and the water impermeable sheet being disposed on the other side of the hygroscopic layer, to thereby sandwich the hygroscopic …
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 March 28, 1991 and granted January 22, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 28, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 28, 2013.
- 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.