Patents by Inventor JoAnn D. Hanna

JoAnn D. Hanna 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).

  • Method of passivating a silver donor with a dye and photothermographic systems made thereby
    Patent number: 6576411
    Abstract: The invention is directed to a color photothermographic film in which particles comprising an organic silver salt is treated with a dye that functions as a passivating agent. In particular, the present invention involves passivating the organic silver salts with a dye that blocks the surface of the organic silver salt or ligand, resulting in a reduction of speed loss. The invention is also directed to a method of making a photothermographic element to improve raw stock keeping.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: June 10, 2003
    Assignee: Eastman Kodak Company
    Inventors: Mark E. Irving, Gregg P. Bryant, JoAnn D. Hanna, Mark R. Mis, Nancy B. Liebert
  • Core/shell silver donors for photothermographic systems comprising an oxidatively less reactive shell
    Patent number: 6548236
    Abstract: The present invention is directed to a photothermographic element comprising silver halide, a blocked developer, a coupler, and core/shell particles, each such particle comprising a mixture of at least two non-photosensitive organic silver salts, which particle comprises a center portion comprising a non-photosensitive first organic silver salt and at least one shell portion covering the center portion, the shell comprising a non-photosensitive second organic silver salt. The organic silver salt in the shell has a higher pKsp relative to the organic silver salt in the core. This invention also provides a composition comprising core/shell non-photosensitive organic silver salt particles, and a method of making the particles.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: April 15, 2003
    Assignee: Eastman Kodak Company
    Inventors: Mark E. Irving, David H. Levy, JoAnn D. Hanna, Stephen Swingley, Donald L. Black, Stephen C. Stoker
  • Method of passivating silver donors in photothermographic systems and imaging elements made thereby
    Patent number: 6497999
    Abstract: The invention is directed to a color photothermographic film in which particles comprising an organic silver salt is treated with a passivating agent. In particular, the present invention involves passivating the organic silver salts with an organic adsorbate that blocks the surface of the organic silver salt or ligand, resulting in a reduction of speed loss. The invention is also directed to a method of making a photothermographic element to improve raw stock keeping.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: December 24, 2002
    Assignee: Eastman Kodak Company
    Inventors: Gregg P. Bryant, JoAnn D. Hanna, Nancy B. Liebert, Mark E. Irving