Process for manufacturing petroleum resin
CA 2062332 C · Owner: Maruzen Petrochemical Co. Ltd. · Inventors: Ochiai, Fumio; Ikeda, Yo-Ichi; Minomiya, Katsumi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for manufacturing a petroleum resin is disclosed. The process comprises, polymerizing a petroleum fraction containing unsaturated hydrocarbons in the presence of a Friedel-Crafts catalyst, and washing the polymerized product with water or an alkaline solution in the presence of 1-200 ppm of a polymer having a hydroxyl value of 40-120 mg KOH/g and represented by formula (I): wherein R1 represents a C4-16 alkyl group each R2, individually represents H or a methyl group each X, individually represents H, an alkyl or an aminomethyl group n is an integer of 0-8, and m is an integer of 8-20. The process can remarkably shorten the time required for the separation of oil from water after …
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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 March 5, 1992 and granted September 17, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 5, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 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
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.