Method for purifying semiconductor gases
CA 2365027 A1 · Owner: Holmer, Arthur Edward · Inventors: Salim, Sateria; Holmer, Arthur Edward; Shrewsbury, Ronald William
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention is directed a method for purifying an impure gas to produce an ultra-high purity gas comprising the steps of a) passing the impure liquefied gas through a first absorption means to remove impurities from the liquid phase therein to produce a first purified fluid; b) passing the first purified fluid through an evaporation means to remove impurities therein to produce a second purified gas; and c) passing the second purified gas through a second absorption means to remove impurities from the vapor phase therein to produce the ultra-high purity gas.
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 December 12, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 12, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 12, 2023.
- 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.