Tungsten hexacarbonyl in plastic lenses
CA 1105696 A · Owner: Ppg Industries, Inc. · Inventors: Leatherman, Ivan R.; Misura, Michael S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Tungsten hexacarbonyl acts as a photochromic agent and an infrared absorber when incorporated in a liquid glycol bis(allyl carbonate) such, as allyl diglycol carbonate, and polymerizates thereof. Photochromic infrared-sbsorbing optical and ophthalmic lenses containing tungsten derived from tungsten hexacarbonyl are made.
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 July 28, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 28, 1998.
- 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.