Optical disk substrate
CA 1317675 C · Owner: Mitsubishi Kasei Corporation · Inventors: Kasahara, Kanji; Murayama, Masamitsu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical disk substrate made of a non-crystalline thermoplastic resin comprising from 80 to 100% by weight of a vinyl cyclohexane polymer (A) containing at least 80% by weight of a vinyl cyclohexane component in the molecular chain and from 0 to 20% by weight of a vinyl aromatic polymer (B) and having a light transmittance of at least 85%, a water absorbance of at most 0.1% by weight and a double refraction of at most 50 nm.
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 11, 1993. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 11, 2010.
- 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.