Light-polarizing film
CA 1269555 C · Owner: Sumitomo Chemical Company, Limited · Inventors: Kikui, Hitoshi; Okada, Toyokazu; Okumura, Takuzo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A highly durable light-polarizing film, having neutral gray as well as high polarizing coefficient is provided. The film comprises a uniaxially stretched base polymer film of for example, polyvinyl alcohol or derivatives thereof and at least two dichroism dyes adsorbed and orientated therein. The dichroism dyes are, for example C.I. Direct Yellow 12, C.I. Direct Black 17 and C.I. Direct Blue 202. The film is usable for display by liquid crystal.
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 29, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 29, 2007.
- 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.