Patents by Inventor Robert John Opitz

Robert John Opitz has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Weakly alkaline ascorbic acid developing composition, processing kit and method using same
    Patent number: 5853964
    Abstract: A black-and-white developing composition includes as ascorbic acid developing agent, an auxiliary super-additive developing agent, borate buffer and a preservative. The composition pH is from 7 but less than 9. The composition can be formulated from two separately packaged parts that may be in dry or liquid form. The borate buffer is present to maintain the desired pH, and the two developing agents are present in desired molar ratios for optimal developing activity. Improved photographic properties are obtained while avoiding the use of environmentally unfriendly dihydroxybenzenes.
    Type: Grant
    Filed: December 17, 1997
    Date of Patent: December 29, 1998
    Assignee: Eastman Kodak Company
    Inventors: Robert John Opitz, Silvia Zawadzki
  • Weakly alkaline ascorbic acid developing composition, processing kit and method using same
    Patent number: 5756271
    Abstract: A black-and-white developing composition includes as ascorbic acid developing agent, an auxiliary super-additive developing agent, borate buffer and a preservative. The composition pH is from 7 but less than 9. The composition can be formulated from two separately packaged parts that may be in dry or liquid form. The borate buffer is present to maintain the desired pH, and the two developing agents are present in desired molar ratios for optimal developing activity. Improved photographic properties are obtained while avoiding the use of environmentally unfriendly dihydroxybenzenes.
    Type: Grant
    Filed: May 27, 1997
    Date of Patent: May 26, 1998
    Assignee: Eastman Kodak Company
    Inventors: Robert John Opitz, Silvia Zawadzki
  • Weakly alkaline ascorbic acid developing composition, processing kit and method using same
    Patent number: 5702875
    Abstract: A black-and-white developing composition includes as ascorbic acid developing agent, an auxiliary super-additive developing agent, borate buffer and a preservative. The composition pH is from 7 but less than 9. The composition can be formulated from two separately packaged parts that may be in dry or liquid form. The borate buffer is present to maintain the desired pH, and the two developing agents are present in desired molar ratios for optimal developing activity. Improved photographic properties are obtained while avoiding the use of environmentally unfriendly dihydroxybenzenes.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: December 30, 1997
    Assignee: Eastman Kodak Company
    Inventors: Robert John Opitz, Silvia Zawadzki