Process for producing information carrying discs
CA 1112408 A · Owner: Thomson-Brandt · Inventors: Bricot, Claude; Robin, Gerard; Le Carvennec, Francois
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The process according to the invention uses a matrix engraved by any means, the tracks being perfectly centered on this matrix in relation to a center of rotation. The matrix is placed in a vacuum chamber on a supporting axis capable of rotating and is coated over its entire surface with a polymerisable material which is free from air bubbles and which does not adhere to the constituent material of the matrix. A substrate previously drilled at its center balanced and coated, with a material to which the polymerisable material adheres is placed on the supporting shaft and held at a distance from the matrix. The vacuum is established in the chamber and the substrate is brought into contact …
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 November 17, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 17, 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.