Forte Photochemical Industry

Janos Becso

Laszlo Toke

Miklos Szucs

Laszlo Fenichel

Peter Bako

Judit Csaplaros

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.

Growing community of inventors

Vac, Hungary

Janos Becso