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:
Nov. 19, 1996
Filed:
Aug. 26, 1994
Richard L Daubendiek, Rochester, NY (US);
Donald L Black, Webster, NY (US);
Joseph C Deaton, Rochester, NY (US);
Timothy R Gersey, Rochester, NY (US);
Joseph G Lighthouse, Rochester, NY (US);
Myra T Olm, Webster, NY (US);
Xin Wen, Rochester, NY (US);
Robert D Wilson, Rochester, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
A chemically and spectrally sensitized ultrathin tabular grain emulsion is disclosed including tabular grains (a) having {111} major faces, (b) containing greater than 70 mole percent bromide and at least 0.25 mole percent iodide, based on silver, (c) accounting for greater than 90 percent of total grain projected area, (d) exhibiting an average equivalent circular diameter of at least 0.7 .mu.m, and (e) exhibiting an average thickness of less than 0.07 .mu.m. It has been observed that increased speed and contrast as well as improvements in speed-granularity relationships can be realized when during the chemical sensitization silver and halide ions including iodide and chloride ions are added to the ultrathin tabular grain host emulsion to deposit epitaxially on up to 50 percent of the surface area of the tabular grains silver halide protrusions (a) having an isomorphic face centered cubic crystal lattice structure, (b) containing at least a 10 mole percent higher chloride ion concentration than the tabular grains, and (c) containing an iodide concentration that is increased by the iodide ion addition.