A cement additive, a concrete composition and a structure using the same
CA 2363087 C · Owner: Shimoyama, Yoshihide · Inventors: Ayata, Takashi; Tanaka, Satoshi; Shimoyama, Yoshihide
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A cement additive composition for preventing discoloration of the surface of concrete, comprising a cement additive (a) and a water-reducing admixture (b), the additive (a) comprising a mixture of compounds represented by the general formula (1) : R1O(AO)n1H .multidot. (1) (wherein R1 is a C1-6 alkyl group, A is an ethylene group and/or a propylene group, and n, is a number of 1 or more) containing all the compounds , satisfying n1 = 2 to 6 in a total amount of not less than 40 % by mass and , having an average n1 of 1.5 to 10 a molecular weight distribution Mw/Mn of not less than 1.05, a Z average molecular weight Mz of not less than 200 and a ratio of (a) : (b) by mass of (5 to …
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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 December 15, 2000 and granted February 14, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 15, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 15, 2022.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.