Patents by Inventor Pieter Jan Willem Bongertman

Pieter Jan Willem Bongertman 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).

  • Method of preparing electrode pitches
    Patent number: 3970542
    Abstract: A method for the preparation of electrode pitch which includes mixing a highly aromatic residual fraction from petroleum raw materials with a coal tar pitch in a weight ratio of from 1:9 to 9:1 and heating the mixture at a temperature of above 350.degree.C. until a pitch is produced with a softening point above 60.degree.C., an insolubility in anthracene oil and toluene is over 30 percent and a coking value of at least 50 corresponding to binder pitch for the production of carbon, graphite electrodes and refractory material.
    Type: Grant
    Filed: November 15, 1974
    Date of Patent: July 20, 1976
    Assignee: Cindu N.V.
    Inventor: Pieter Jan Willem Bongertman