Patents by Inventor David Hacker

David Hacker 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).

  • Erasable colored pencil lead
    Patent number: 6011084
    Abstract: The present invention provides a colored pencil lead composition comprising a colorant, one or more binder resins, a fibrillatable or fibrillated material, a non-fibrillatable particulate lubricant, and a filler. An example of a suitable binder resin is high density polyethylene, and an example of a fibrillated or fibrillatable material is fibrillatable polytetrafluoroethylene. An example of a non-fibrillatable particulate lubricant is micronized polytetrafluoroethylene. The colored pencil lead of the present invention produces marks on paper which are easily erased by ordinary pencil eraser. The present invention further provides a process for preparing the colored pencil lead of the present invention comprising compounding the colorant, the binder resin or resins, the fibrillatable or fibrillated material, the non-fibrillatable particulate lubricant, and the filler to obtain a blend and forming the pencil lead from the blend.
    Type: Grant
    Filed: June 26, 1998
    Date of Patent: January 4, 2000
    Assignee: Binney & Smith Inc.
    Inventors: Jacob Leidner, David Hacker