Patents by Inventor Joseph Hall

Joseph Hall 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: 4842974
    Abstract: A liquid composition for developing latent electrostatic images comprising toner particles associated with a pigment dispersed in a nonpolar liquid. The salient feature of the invention is that the toner particles are formed with a plurality of fibers of tendrils from a thermoplastic polymer and carry a charge of a polarity opposite to the polarity of the latent electrostatic image. The polymer is insoluble or insolvatable in the dispersant liquid at room temperature. The toner particles are formed by plasticizing the polymer and pigment at elevated temperature and then either permitting a sponge to form and wet-grinding pieces of the sponge or diluting the plasticized polymer-pigment while cooling and constantly stirring to prevent the forming of a sponge while cooling. When cool, the diluted composition will have a concentration of toner particles formed with a plurality of fibers.
    Type: Grant
    Filed: June 11, 1987
    Date of Patent: June 27, 1989
    Assignee: Savin Corporation
    Inventors: Benzion Landa, Peretz Ben-Auraham, Joseph Hall, George A. Gibson