Styrene-dialkyl maleate copolymers as dewaxing agents
CA 1254530 A · Owner: Nalco Chemical Company · Inventors: Millard, Alan A.; Wang, Sophia
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A solvent dewaxing process for dewaxing waxy lubricating oil with a dewaxing solvent and a dewaxing aid which comprises using as the dewaxing aid a styrene dialkyl maleate copolymer wherein the side chain groups contain from C16 - C24 + carbon atoms. These polymers are further characterized as having a molecular weight within the range of 10,000 - 150,000.
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
- Granted May 23, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 23, 2006.
- 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.