SILVER HALIDE PHOTOGRAPHIC MATERIAL Russian patent published in 1999 - IPC

FIELD: light-sensitive materials. SUBSTANCE: invention relates to manufacturing various- destination black-and-white photographic materials. Materials include support covered with light-sensitive layer made of chemically and spectrally sensitized silver halide emulsion with tablet-shaped microcrystals with ratio of average diameter to average thickness at least 2:1, average diameter being at least 0.3 mcm; and protective hydrophilic colloidal layer. Light-sensitive and/or protective layer contains nitrogen-containing heterocyclic compound with general formula I: (I), wherein X is sulfur, oxygen, NR⁴ (R⁴ is hydrogen or lower alkyl), and lower hydroxyalkyl; Y is CO or C(R⁴)₂; Q oxygen or sulfur; R¹ and R², the same or different, are hydrogen, lower alkyl, alkoxyl, R⁵SO₃M, R⁵-aryl (R⁵ is lower alkyl and M hydrogen, alkali metal, phenyl or substituted phenyl) or -R⁵-O-R⁵; Z¹ is hydrocarbyl closing nitrogen-containing heterocycle, e. g. pyrrolydine, thiazolidine, oxazolidine, imidazole, pyrrol, pyridine, thiazole, oxazole, quinoline, indole, benzothiazol, benzoxazole, benzimidazole, benzoquinoline, benzoindole, naphthothiazole, naphthoxazole, or naphthoimidazole; R³ hydrogen, lower alkyl, alkoxyl, hydroxyl, halogen, SO₃M, COOM, SR⁶ (R⁶ is hydrogen, lower alkyl, or halogen- substituted lower alkyl), aryl, or benzo group; n=0 or 2; or compound with general formula II: (II), wherein R⁷ and R⁸, the same or different, are hydrogen, lower alkyl, alkylene, -R¹¹-COO^-, , -R¹¹-SO₃, -R¹¹-O-R¹¹, -R¹¹-aryl (R¹¹ is lower alkyl, arylphenyl, or substituted phenyl); Z² and Z³ have the same meanings as Z¹ in formula I; R⁹ and R¹⁰ have the same meanings as R³ in formula I; X^- is anion such as Hal^-, ClO-4

,, or ; K⁺ is cation such as -NH+4, (NH(R¹¹)+3, or ; if R⁷ contains acid group in anionic form, X^- is missing; if R⁸ contains no acid group in anionic form, K⁺ is missing; m=1 or 3; in amount 1•10^-7-1•10^-5 mole per 1 mole of silver halide in light-sensitive layer. EFFECT: increased information density of photographic material due to reduced (by 10- 30%) light scattering and, in some cases, increased both total and effective light-sensitivity. 2 tbl, 10 ex