Method and means for producing photomasks
CA 2074714 A1 · Owner: Presstek, Inc. · Inventors: Nowak, Michael T.; Lewis, Thomas E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A novel photomask structure and method of producing photomasks using a non-contacting spark-discharge recording apparatus. The recording constructions of the present invention comprise a conductive layer, a layer transparent to the radiation that will be used to expose the target photosensitive material and optionally, a, coating layer deposited over the metal layer.
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 January 29, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 29, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 29, 2013.
- 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.