Patents by Inventor Fernand I. Ketels

Fernand I. Ketels 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 developing direct positive silver halide material
    Patent number: 5155014
    Abstract: Method for the production of direct-positive images by image-wise exposing a light-sensitive silver halide material comprising a support and an internal latent image-type silver halide emulsion layer and developing said exposed material in the presence of at least one development nucleator and density-increasing amounts of a compound chosen from the class consisting of formic acid, oxalic acid, glyoxylic acid, or salts of these and/or of a compound chosen from the class consisting of polyethylene glycols, with a hydroquinone-type developing solution having a pH not higher than 12.0 and comprising less than 25 g per liter of a hydroquinone and 5 to 100 g per liter of at least one alkanolamine.
    Type: Grant
    Filed: August 14, 1991
    Date of Patent: October 13, 1992
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Jozef P. De Prijcker, Fernand I. Ketels, Jean-Marie O. Dewanckele, Piet Kok