Harold G Judd

US Patent:

6422736, Jul 23, 2002

Filed:

Jun 21, 2000

Appl. No.:

09/598573

Inventors:

Michael G. Antoniades - Rochester NY
Harold G. Judd - Bolingbrook IL
Katrin I. Parsiegla - Rochester NY
Benjamin T. Chen - Penfield NY
Douglas E. Singer - Rochester NY
Donald R. Irwin - Rochester NY
Sucheta Tandon - Fairport NY
Heinz E. Stapelfeldt - Pittsford NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

B01F 722

US Classification:

3661722, 366264, 366270, 422227

Abstract:

A mixer for preparing silver halide grains for photographic use has upper and lower impellers housed in a draft tube. The bottom impeller has flat blades for micromixing silver and halide reactants introduced into the bottom of the draft tube. The upper impeller has pitched blades for macromixing the bulk fluid. The impellers are spaced apart at least the distance of their diameters so that the upper and lower impellers operate independently of one another so that micromixing is independent of macromixing. A flow disrupter structurally associated with the draft tube and positioned above the top impeller prevents vortexing of the fluid during mixing. Baffles may be provided in the draft tube to discourage vortexing.

US Patent:

57363129, Apr 7, 1998

Filed:

Nov 20, 1996

Appl. No.:

8/753073

Inventors:

Seshadri Jagannathan - Rochester NY
Harold G. Judd - Rochester NY
Samuel Chen - Penfield NY
David E. Fenton - Fairport NY
Allen K. Tsaur - Rochester NY
Kenneth J. Reed - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

G03C 1035
G03C 1015

US Classification:

430569

Abstract:

A process of preparing a photographic emulsion having radiation-sensitive silver iodohalide grains. Iodide is introduced into the grains by releasing iodide ions from iodate (IO. sub. 3. sup. -). Release of iodide ions from the IO. sub. 3. sup. - is employed to enhance the uniformity of iodide availability during emulsion preparation, either during grain precipitation or subsequent halide conversion. The process of the invention is in one preferred form directed to the partial halide conversion of tabular grains. A speed-granularity advantage is demonstrated.