Patents Assigned to Park Management and Development Co.
  • Patent number: 4262623
    Abstract: A plurality of fingerprints of a person are recorded by applying a solution of a first substantially colorless chemical reagent to the fingertips. Essentially invisible fingerprints are obtained by gently pressing the fingers having the solution of the first chemical reagent thereon on a suitable recording sheet. Subsequently the recording sheet is exposed to sublimed vapors of a second chemical reagent. The first and second chemical reagents are selected to react with one another to yield a highly colored substance which is formed on the surface of the recording sheet providing a visible image of the fingerprints. Ferric chloride and a 8-hydroxyquinoline are ideally suited chemical reagents for use in this invention. An apparatus of unitary construction incorporating a replaceable dispensing pad having the solution of the first chemical, is disclosed.
    Type: Grant
    Filed: December 11, 1978
    Date of Patent: April 21, 1981
    Assignee: Park Management and Development Co.
    Inventors: Jay Smith, III, Virgile L. Hedgcoth, Thomas H. Grimm