Patents by Inventor James R. Stephens

James R. Stephens 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).

  • Self-bonding varnish for magnet wires comprising a polyalkylenetrimellitate ester imide
    Patent number: 4012556
    Abstract: Magnet Wire Bearing a Self-Bonding Poly(alkylenetrimellitate ester imide) varnish coating which is capable of forming a unitary structure after producing a fabricated article from the coated wire wherein the varnish layer bonds on heating.
    Type: Grant
    Filed: February 23, 1976
    Date of Patent: March 15, 1977
    Assignee: Standard Oil Company (Indiana)
    Inventors: Robert G. Keske, James R. Stephens
  • Process for preparing polyamide-imide from trimellitic acid, diamine and diisocyanate and polyamide imide shaped articles
    Patent number: 3959233
    Abstract: Polyamide-imides are prepared by reacting trimellitic acid with an aromatic or an aliphatic diamine in the molar ratio of about 1:0.55 to 1:0.95 and then reacting this product with at least 0.45 to about 0.75 moles to about 0.05 to about 0.35 moles of an aromatic diisocyanate. The products are useful as wire enamels and coatings when they are formulated into wire enamels and coated on electrical conductors. They may also be used as molding resins.
    Type: Grant
    Filed: April 9, 1973
    Date of Patent: May 25, 1976
    Assignee: Standard Oil Company (Indiana)
    Inventors: Robert B. Hanson, James R. Stephens