Super-high contrast silver halide material
CA 2071499 A1 · Owner: Altavilla, Alexander · Inventors: Altavilla, Alexander
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A silver halide photographic material and a method for processing the photographic material to form a super high contrast negative image are disclosed. The photographic material comprises a radiation-sensitive silver halide grains capable of forming a surface latent image, a binder, a dot quality-promoting amount of a hydrazine or hydrazide compound and a pepper-reducing effective amount of a compound of formula (II), wherein R'1 is selected from the group consisting of benzothiazole, quinoline indolenine, nitrobenzothiazole, benzotriazole and rhodanine each of which may be , substituted or unsubstituted and m is an integer between 0 and 6, inclusive.
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 December 17, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 17, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 17, 2012.
- 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.