Patents by Inventor Al Kratzer

Al Kratzer 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: 5264080
    Abstract: Archival quality aperture cards manufactured from stock formulation including:1. between 40 and 60% southern softwood kraft pulp;2. between 60 and 40% northern mixed hardwood pulp;3. between 1.5 and 2.5% on total pulp, calcium carbonate for alkaline reserve;4. between 0.05 and 1.0% on total pulp, alkyl ketene dimer as an internal sizing agent;5. between 0.2 and 1.0% on total pulp, cationic potato starch for internal bonding improvements;6. between 0.5 and 2.0% on total pulp, cationic potato starch as a surface sizing agent;7. between 0.5 and 2.5% solids added to the surface sizing agent, alkyl ketene dimer as a slip agent; and8. between 0.01 and 0.3% dyed rayon granitizing fibers.
    Type: Grant
    Filed: July 31, 1992
    Date of Patent: November 23, 1993
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Jeffry S. Shaw, Al Kratzer, James M. Harris