Process and apparatus for the formation of negative resist pattern
CA 2001852 A1 · Owner: Yamatoya & Co. Ltd · Inventors: Numakura, Iwao
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A negative resist pattern is formed using a resist containing a diazoquinone sensitizer. An imagewise exposed area of a layer of the resist is subjected to heat treatment with a water-containing heating medium in the presence of a carboxyl-inactivating agent. The entire surface of the layer is exposed to radiation. The thusexposed surface is then treated with an alkaline developer solution. An apparatus suitable for use in the practice of the above process is also disclosed.
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 October 31, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 31, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 31, 2011.
- 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.