Eastman-Kodak Company

Victor P Scaccia

Joe E Maskasky

David A Dickinson

Kenneth Joseph Reed

Samuel Chen

James A Friday

Mark Lelental

Thomas N Blanton

Roger L Klaus

Peter John Ghyzel

John W Boettcher

James L Wakley

Richard L Gaines

Black-and-white direct thermographic materials and photothermographic materials can be processed or developed at lower temperatures because of the incorporation of a quaternary ammonium salt in an amount of at least 0.5 mol % based on total silver in the material.

Thermally developable materials processable at lower temperatures

Silver-free, aqueous-based direct thermographic materials are designed to have image tone with near neutral density. Without the use of organic silver salts containing reducible silver ions, the image is formed using a color developing agent precursor that releases a color developing agent when heated to a temperature of at least 80&#xb0; C., a combination of cyan, yellow and magenta dye-forming color couplers that provide cyan, yellow, and magenta dyes, and a substituted or unsubstituted benzoquinone as an oxidizing agent. No silver metal or silver ions are purposely added to these materials. This combination of components provides a means for controlling image tone without reliance upon conventional toning agents.

Silver-free black-and-white thermographic materials containing a benzoquinone and methods of imaging

Silver-free, aqueous-based direct thermographic materials are designed to have image tone with near neutral density. Without the use of organic silver salts containing reducible silver ions, the image is formed using a color developing agent precursor that releases a color developing agent when heated to a temperature of at least 80&#xb0; C., a combination of cyan, yellow and magenta dye-forming color couplers that provide cyan, yellow, and magenta dyes, and a hindered-amine N-oxyl as an oxidizing agent. No silver metal or silver ions are purposely added to these materials. This combination of components provides a means for controlling image tone without reliance upon conventional toning agents.

Silver-free black-and-white thermographic materials

Aqueous-based thermally sensitive emulsions and photothermographic imaging materials include photosensitive silver halide grains that comprise at least 15 mol % iodide based on total silver in the grains and are doped with bismuth (+3). These materials have increased photographic speed especially in the infrared region of the electromagnetic spectrum.

Photothermographic materials containing doped high iodide emulsions

The present disclosure relates to aqueous dispersions of silver (carboxylate-azine toner) particles wherein the azine content of the particles is from about 0.01 to 10% by weight relative to silver carboxylate. The carboxylates are typically silver salts of long chain fatty acids and the azine toners are the compounds that function as development accelerators and toning agents such as phthalazine. These silver (carboxylate-azine) particles can be used to formulate imaging forming compositions that are useful in aqueous thermographic or photothermographic imaging elements.

Silver-(carboxylate-azine toner) particles for photothermographic and thermographic imaging

Aqueous-based thermally developable emulsions and photothermographic imaging materials include photosensitive silver halide core-shell grains that comprise at least 20 mol % iodide based on total silver, an amount of iodide in the core of the grains that can be up to the iodide saturation limit in silver iodobromide, and an amount of iodide in the shell of the grains that is at least 2 mol % less than the amount of iodide present in the core, and further provided that the total amount of silver in the shell is from about 10 to about 80 mol % of total silver in the grains. These materials provide desired D and reduced image &ldquo;print out&rdquo;.

Photothermographic materials containing high iodide core-shell emulsions

Silver-(carboxylate-azine toner) particles for photothemographic and thermographic imaging

Aqueous-based thermally sensitive emulsions and photothermographic imaging materials include phthalazine N-oxide or a derivative thereof to improve raw stock keeping and to extend the useful range of processing temperatures without interfering with spectral sensitization. The emulsions and photothermographic materials may also include a cyclic imide, phthalazinone, benzoxazine dione, benzthiazine dione, or quinazoline dione as a development promoter.

Thermally sensitive imaging materials containing phthalazine precursor

A process for precipitating a high bromide silver halide emulsion in an aqueous medium is disclosed comprising growing nucleated silver halide grains in a reaction vessel in the presence of a peptizer comprising a water dispersable starch to form high bromide radiation-sensitive silver halide grains, wherein the majority of grain growth in the reaction vessel is performed at a pH of less than 3.5. Growth of high bromide silver halide emulsion grains in the presence of a starch peptizer at low pH in accordance with the invention results in emulsion grains with lower fog, even in the absence of the use of strong oxidizing agents during grain precipitation.

Preparation of high bromide photographic emulsions with starch peptizer

A process for precipitating a high bromide silver halide emulsion in an aqueous medium is described comprising precipitating high bromide radiation-sensitive silver halide grains in a reaction vessel in the presence of a peptizer comprising a water dispersable starch, wherein a strong oxidizing agent is added to the reaction vessel during or after the precipitation at a pH of less than 4.0 such that an oxidation potential of at least 650 mV (Ag/AgCl ref.) is achieved. A reduction in the rate of reaction between strong oxidants such as bromine and starch at such low pH has been found to enable an advantageous decrease in the amount of oxidant required to achieve and maintain a high oxidation potential during emulsion grain precipitation. Starch, unlike gelatin, also advantageously has adequate stability at the combination of high acidity and high emulsion precipitation temperatures.

Preparation of high bromide photographic emulsions with starch peptizer and oxidizing agent

A process for precipitating a high chloride silver halide emulsion in an aqueous medium is disclosed comprising growing nucleated silver halide grains in a reaction vessel in the presence of a peptizer comprising a water dispersable starch to form high chloride radiation-sensitive silver halide grains, wherein the majority of grain growth in the reaction vessel is performed at a pH of less than 3.5. Growth of high chloride silver halide emulsion grains in the presence of a starch peptizer at low pH in accordance with the invention results in emulsion grains with lower fog, even in the absence of the use of strong oxidizing agents and antifoggants during grain precipitation.

Preparation of high chloride photographic emulsions with starch peptizer

A multicolor photographic element comprising a support bearing a cyan dye image-forming unit comprising at least one red-sensitive silver halide emulsion layer having associated therewith at least one cyan dye-forming coupler, a magenta dye image-forming unit comprising at least one green-sensitive silver halide emulsion layer having associated therewith at least one magenta dye-forming coupler, a yellow dye image-forming unit comprising at least one blue-sensitive silver halide emulsion layer having associated therewith at least one yellow dye-forming coupler, wherein at least one of said emulsion layers comprises tabular grains having &lcub;111&rcub; major faces containing greater than 50 mole percent bromide, and accounting for greater than 50 percent total grain projected area precipitated in a peptizer that is a water dispersible cationic starch, and contains a fragmentable electron donating sensitizer.

Color photographic element containing a fragmentable electron donor in combination with a one equivalent coupler and starch peptized tabular emulsion for improved photographic response

A photographic recording element is disclosed containing in at least one dye image forming layer unit (a) a radiation-sensitive silver halide grains include tabular grains (1) having &lcub;111&rcub; major faces, (2) containing greater than 50 mole percent bromide, based on silver, and (3) accounting for greater than 50 percent total grain projected area, (b) a fragmentable electron donating sensitizer, (c) a water dispersible cationic starch peptizer, and (d) a one equivalent dye image providing coupler. Increased photographic speed is realized.

Color photographic elements of increased sensitivity containing one equivalent coupler

A photographic emulsion is disclosed containing for enhanced imaging speed high bromide {111} tabular grain emulsion peptizer with a cationic starch and sensitized with a fragmentable electron donating sensitizer. The photographic emulsion is disclosed for use in black-and-white and color photographic elements.

Photographic emulsions and elements of increased sensitivity

A photographic element is disclosed having at least one emulsion layer comprised of (a) radiation-sensitive silver halide grains, (b) sensitizer for the radiation-sensitive silver halide grains, (c) hydrophilic colloid vehicle, including peptizer for the radiation-sensitive silver halide grains, and (d) light scattering particles, wherein (a) the radiation-sensitive silver halide grains include tabular grains (1) having an aspect ratio of at least 2.0, (2) having {111} major faces, (3) containing greater than 50 mole percent bromide, based on silver, and (4) accounting for greater than 50 percent total grain projected area, (b) the sensitizer includes a fragmentable electron donating sensitizer, (c) the peptizer is a water dispersible cationic starch, and (d) the light scattering particles have aspect ratios of less than 1.5 and can be dissolved for removal from the emulsion layer. The photographic elements exhibit enhanced imaging speed and can be employed for color or black-and-white photographic imaging.

Growing community of inventors

Rochester, NY, United States of America

Victor P Scaccia