Positive photoresist composition
CA 2240564 A1 · Owner: Yako, Yuko · Inventors: Fukui, Nobuhito; Yako, Yuko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A chemical amplifying type positive photoresist composition, excellent in various properties particularly, in TDE resistance as well as sensitivity and resolution and able to suppress unfavorable halation effect without deteriorating profile, which comprises (A) a resin which is converted to alkali-soluble from alkali-insoluble or alkali slightly soluble by the action of an acid (B) an, acid generator, (C) a basic compound and (D) a fluorenone compound represented by the following formula (I): wherein R1, R2, R3, R4, R5, R6, R7 and R8 each independently represent hydrogen, alkyl having 1 to 6 carbon atoms which may be optionally substituted with halogen halogen or nitro, is provided; and a …
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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 June 12, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 12, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 12, 2020.
- 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.