Water repellent and water repellent gypsum composition
CA 2010340 C · Owner: Tagawa, Toru · Inventors: Ozawa, Yasoji; Tadenuma, Takao; Tagawa, Toru
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A water repellent having the following components (A), (B), (C) and (D) emulsified in water: (A) a wax having a melting point of from 40 to 90°C; (B) a styrene-malefic anhydride copolymer; (C) a water-soluble alkaline compound; and (D) a polyvinyl alcohol having a saponification degree of at least 85 mol%.
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 February 19, 1990 and granted September 21, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 19, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 19, 2012.
- 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.