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. 12, 1996
Filed:
May. 15, 1995
Richard L Daubendiek, Rochester, NY (US);
Joseph C Deaton, Rochester, NY (US);
Donald L Black, Webster, 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 tabular grain emulsion is disclosed including tabular grains (a) having 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 (f) exhibiting an average thickness in the range of from less than 0.3 .mu.m to at least 0.07 .mu.m. It has been observed that increased speed, lower granularity, increased contrast and faster rates of development can be realized when (1) the tabular grains contain less than 10 mole percent iodide and (2) the surface chemical sensitization sites include epitaxially deposited silver halide protrusions of a face centered cubic crystal lattice structure of the rock salt type forming epitaxial junctions with the tabular grains, the protrusions (a) being restricted to those portions of the tabular grains located nearest peripheral edges of and accounting for less than 50 percent of the major faces of the tabular grains, (b) containing a silver chloride concentration at least 10 mole percent higher than that of the tabular grains, and (c) including at least 1 mole percent iodide.