Patents by Inventor Paul D. Marsh

Paul D. Marsh 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).

  • Injection molding process with reactive gas treatment
    Patent number: 4800053
    Abstract: A process for making shaped articles by injecting a thermoplastic or thermoset polymer into a mold cavity in which is maintained a reactive atmosphere containing between 0.1 mole % and 50 mole % F.sub.2 and at least 20 ppm O.sub.2 while the polymer is being injected into the mold, such that any portion of the polymer contacts the reactive atmosphere for a time not greater than 0.5 sec.
    Type: Grant
    Filed: April 26, 1988
    Date of Patent: January 24, 1989
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Bernard D. Bauman, David R. Ruprecht, Paul D. Marsh, Mark A. Williams
  • Injection molding process with reactive gas treatment
    Patent number: 4752428
    Abstract: The present invention is a process for making shaped articles by injecting a thermoplastic or thermoset polymer into a mold cavity in which is maintained at atmosphere containing between 0.1 mole % and 50 mole % F.sub.2 and at least 20 ppm O.sub.2 while said polymer is being injected into the mold. The process results in shaped articles having altered physical and chemical characteristics. A weld line formed where two interfaces of the polymer are joined in the mold cavity serves as a clean break point when pressure is applied to an article formed by the process. The atmosphere in the mold cavity may contain SO.sub.3.
    Type: Grant
    Filed: January 28, 1987
    Date of Patent: June 21, 1988
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Mark A. Williams, Bernard D. Bauman, David R. Ruprecht, Paul D. Marsh