Michael D Purol

US Patent:

55001254, Mar 19, 1996

Filed:

May 19, 1994

Appl. No.:

8/245797

Inventors:

Richard R. Horn - Fairport NY
Christine K. Gaskell - Rochester NY
Susan R. Krauss - Pittsford NY
Michael D. Purol - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

C02F 900

US Classification:

210668

Abstract:

A method of treating photoprocessing wash water, comprising in sequence, the steps of: A) contacting the wash water with an acrylic anion exchange resin to remove silver thiosulfate complex in the water; and B) contacting the water from step A) with an oxidizing agent that converts thiosulfate ions to sulfate ions. C) recirculating continuously through the photoprocessing wash tank and steps A) and B).

US Patent:

52643239, Nov 23, 1993

Filed:

Dec 14, 1992

Appl. No.:

7/990350

Inventors:

Michael D. Purol - Rochester NY
Paul A. Zielinski - Rochester NY
Donald L. Kerr - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

G03C 106

US Classification:

430264

Abstract:

An improved photographic developing solution is free of dihydroxybenzene developing agents such as hydroquinone, has a pH in the range of from 9. 5 to 11. 5 and comprises (1) an ascorbic acid developing agent, (2) an auxiliary super-additive developing agent and (3) a carbonate buffering agent in a concentration of at least 0. 5 molar. The developing solution is broadly useful in black-and-white development but is most advantageously employed in a process for forming a high-contrast image utilizing a silver halide photographic element comprising a hydrazine compound which functions as a nucleating agent and an amino compound which functions as an incorporated booster. The developing solution is ecologically advantageous, exhibits excellent stability with respect to seasoning effects, and provides high speed and good upper scale contrast combined with a low level of pepper fog and a moderate degree of chemical spread.

US Patent:

52368165, Aug 17, 1993

Filed:

Apr 10, 1992

Appl. No.:

7/866604

Inventors:

Michael D. Purol - Rochester NY
Paul A. Zielinski - Rochester NY
Donald L. Kerr - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

G03C 530

US Classification:

430492

Abstract:

An improved photographic developing solution is free of dihydroxybenzene developing agents such as hydroquinone, has a pH in the range of from 9. 5 to 11. 5 and comprises (1) an ascorbic acid developing agent, (2) an auxiliary super-additive developing agent and (3) a carbonate buffering agent in a concentration of at least 0. 5 molar. The developing solution is broadly useful in black-and-white development but is most advantageously employed in a process for forming a high-contrast image utilizing a silver halide photographic element comprising a hydrazine compound which functions as a nucleating agent and an amino compound which functions as an incorporated booster. The developing solution is ecologically advantageous, exhibits excellent stability with respect to seasoning effects, and provides high speed and good upper scale contrast combined with a low level of pepper fog and a moderate degree of chemical spread.

US Patent:

42647169, Apr 28, 1981

Filed:

Sep 10, 1979

Appl. No.:

6/073770

Inventors:

Sheridan E. Vincent - Rochester NY
Michael D. Purol - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

G03C 530
G03C 716
C02F 510
C11D 1700

US Classification:

430380

Abstract:

Photographic color developer compositions containing a primary aromatic amino color developing agent and an hydroxylamine are stabilized by incorporating therein a combination of sequestering agents, one of which is an aminopolyphosphonic acid compound and another of which is an aromatic polyhydroxy compound. Decomposition of the hydroxylamine, in the presence of heavy metals such as iron which act to catalyze the decomposition, and resultant formation of ammonia is effectively prevented by the presence in the developer composition of this combination of sequestering agents. Undesirable precipitate formation is also effectively avoided.