Patents by Inventor Robert W. Kelsall

Robert W. Kelsall 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).

  • Patent number: 5989781
    Abstract: In accordance with the present invention, there are provided methods for producing printing plates comprising rapid, efficient drying of solvent-containing resin compositions of the printing plates and apparatus useful therefor. Printing plates processed employing invention methods and apparatus are ready for use in printing applications in a relatively short period of time, especially compared to the time required for conventional convection drying. Moreover, printing plates processed according to the present invention method and apparatus are not subjected to excessive levels of heat, as is frequently the case with conventional convection drying. Excessive heating tends to be detrimental to the performance properties of the polymeric resin. In a particular aspect of the present invention, there are provided novel compositions which, upon drying according to the methods described herein, undergo a color change, thereby indicating when the drying process is substantially complete.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: November 23, 1999
    Assignee: NAPP Systems, Inc.
    Inventors: Michael J. Idacavage, Robert W. Kelsall
  • Patent number: 5350661
    Abstract: In accordance with the present invention, there are provided water-developable photopolymerizable compositions useful for the preparation of printing plates. Printing plates prepared employing invention compositions have excellent form stability, thereby enabling such plates to be handled without the need for excessive care. Once photopolymerized, printing plates of the invention have excellent physical properties, enabling their use in many very demanding commercial applications, e.g., commercial flexographic printing. Such applications require the photopolymerized resin to have excellent water resistance (so that exposure to water-based inks does not significantly alter resin properties), as well as high durability (so that the physical contacting associated with the printing process does not significantly degrade resin properties).
    Type: Grant
    Filed: March 25, 1993
    Date of Patent: September 27, 1994
    Assignee: Napp Systems, Inc.
    Inventors: Robert W. Kelsall, Allyson R. Maurer