Rapid image forming process utilizing high chloride tabular grain silver halide emulsions with (iii) crystallographic faces
AssigneeEastman Kodak Company
InventorRichard Peter Szajewski
Life of this patent
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Abstract
Photographic elements having bromide or iodide ion stabilized high chloride {111} tabular grain emulsions are rapidly processed. The emulsion grains comprise a high chloride core with a surrounding band of higher bromide or iodide ion than that found in the core. The emulsion is precipitated in the presence of an organic grain growth modifier or surface stabilizer. Specific developing conditions of temperature, time, bromide ion concentration, color developing agent concentration and ratio of developing agent to bromide ion allow for the rapid processing of these elements.
Claims16
An image forming process comprising a developing step of contacting an imagewise exposed light-sensitive photographic element with a developing solution,
- said element comprising a support having thereon a red light-sensitive color record comprised of a red sensitized silver halide emulsion, a green light-sensitive color record comprised of a green sensitized silver halide emulsion, and a blue light-sensitive color record comprised of a blue sensitized silver halide emulsion, wherein said element exhibits a photographic sensitivity of at least ISO-25, and a chemically and spectrally sensitized emulsion (A), characterized in that:
- emulsion (A) comprises a tabular silver halide emulsion population comprised of at least 50 mole % chloride, based on silver, wherein at least 50% of the grain population projected area is accounted for by tabular grains bounded by {111} major faces, each having an aspect ratio of at least 2 and each being comprised of a core and a surrounding band containing a higher level of bromide or iodide ion than is present in said core, said band containing up to about 30% of the silver in the tabular grain,
- wherein said emulsion (A) has been precipitated in the presence of an organic grain growth modifier or surface stabilizer and wherein said organic grain growth modifier or stabilizer has been substantially removed from said emulsion (A) after the formation of said band, and
- wherein the contact time of said element with said developing solution is from about 10 to about 120 seconds, and
- said developing solution being characterized in that:
- (1) the solution temperature is between about 25.degree. and 65.degree. C.,
- (2) the solution comprises bromide ion at a concentration of from about 3 to about 50 mmol/l,
- (3) the solution comprises a color developing agent at a concentration from about 1 to about 200 mmol/l,
- (4) the ratio of developing agent concentration to bromide ion concentration is from about 30:1 to about 1:1, and
- (5) the solution pH is from about 9 to about 12.
Dependencies are inferred from the claim text.