Patents by Inventor Leslie E. Lawson

Leslie E. Lawson 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 and apparatus for controlling the processing of radiation sensitive plates with a liquid by monitoring the electrical conductivity of the liquid
    Patent number: 4577948
    Abstract: Changes occurring in the electrical conductivity of liquids used to process image-wise exposed radiation-sensitive devices are used as a measure of the deterioration in effectiveness of the liquids. This deterioration is compensated for by varying the processing conditions, such as temperature, time, scrubbing action and processing liquid composition, in accordance with the change in conductivity.
    Type: Grant
    Filed: October 20, 1983
    Date of Patent: March 25, 1986
    Assignee: Vickers PLC
    Inventors: Leslie E. Lawson, Michael Ingham
  • Lithographic fountain concentrates containing a desensitizing material in an organic solvent liquid
    Patent number: 4247328
    Abstract: A concentrate for dilution with water to obtain a fountain solution for lithographic printing comprises a lithographic desensitizing material dissolved in a vehicle liquid comprising an organic solvent liquid optionally in admixture with water. Preferred desensitizing materials are organo substituted ammonium salts of desensitizing acids and a preferred organic solvent liquid is isopropyl alcohol. The fountain solution obtained on dilution of the concentrate may be used with printing machines having integrated damping/inking equipment.
    Type: Grant
    Filed: January 15, 1979
    Date of Patent: January 27, 1981
    Assignee: Vickers Limited
    Inventors: Leslie E. Lawson, Frank E. Smith
  • Processing of radiation sensitive devices
    Patent number: 4240737
    Abstract: During the processing of an image-wise exposed radiation sensitive device, such as a radiation sensitive plate for lithographic printing plate production, by contacting the device with developer liquid, a temperature sensitive member is immersed in the developer liquid. The member produces an output signal in dependence on the temperature of the developer liquid. This signal is used to control the degree to which the device is processed in a manner dependent on the temperature of the developer liquid for example by controlling the residence time of the device in the developer liquid, by controlling the degree to which the developer liquid is agitated in contact with the device, or by controlling the degree to which the device is subjected to an overall exposure to radiation prior to or during contact with the developer liquid.
    Type: Grant
    Filed: June 4, 1979
    Date of Patent: December 23, 1980
    Assignee: Vickers Limited
    Inventor: Leslie E. Lawson
  • Treating developed lithoplate with oleophilic composition
    Patent number: 4191569
    Abstract: A positive working radiation sensitive plate is image-wise exposed, developed and desensitized, and dried. Thereafter an oleophilic composition including a solvent capable of softening the image is applied to the plate and the plate is then washed to remove the oleophilic composition from the non-image areas. The image accepts ink readily even when the image-wise exposure is effected using a continuous tone original in the absence of a half-tone screen.
    Type: Grant
    Filed: July 25, 1977
    Date of Patent: March 4, 1980
    Assignee: Vickers Limited
    Inventor: Leslie E. Lawson