The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 08, 1992
Filed:
Jan. 15, 1991
Miklos Szucs, Budapest, HU;
Judit Csaplaros, Vac, HU;
Janos Becso, Vac, HU;
Laszlo Fenichel, Budapest, HU;
Peter Bako, Budapest, HU;
Laszlo Toke, Budapest, HU;
Forte Photochemical Industry, Vac, HU;
Abstract
The invention relates to a novel process for the chemical sensitization of silver halide photographic emulsions. The process according to the invention comprises adding as additional sensitizing agents a 40-260 .mu. moles/mole of a cyclic polyether containing 1 nitrogen and 5 oxygen atoms, or 2 nitrogen and 4 oxygen atoms, or 3 nitrogen and 3 oxygen atoms, or 4 nitrogen and 2 oxygen atoms as well as 12 carbon atoms and/or their complexes formed with gold and/or palladium and optionally 40-260 .mu. moles/mole of silver halide) of gold (I) or gold (III) sulfide to the sulfur-sensitized emulsion, and employing the cyclic polyether in relation to the noble metal salt in a molar ratio of 0.5:1-5:1 for the complex formation.