Patents by Inventor Paul T. Wombwell

Paul T. Wombwell 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: 5616633
    Abstract: The present invention provides a liquid epoxy resin composition that includes an epoxy resin, at least one filler and an inorganic thixotropic agent in an amount effective to reduce settling of said filler at ambient temperatures. The composition further includes a polymer powder that dissolves in and thickens the composition when the composition is heated. The polymer powder is added in an amount effective to reduce settling of said filler at temperatures up to the gelling temperature of the composition. The thixotropic agent is added in an amount that the resulting epoxy resin composition is a free-flowing liquid. The composition may optionally further include a curing agent.
    Type: Grant
    Filed: September 9, 1994
    Date of Patent: April 1, 1997
    Assignee: Ciba-Geigy Corporation
    Inventors: Paul T. Wombwell, Philip D. Willis, Christopher H. Bull
  • Patent number: 5523044
    Abstract: The present invention provides a process for the manufacture of a moulded article which comprises introducing a curable epoxy resin composition to a mould which is at a temperature high enough to initiate curing of the resin and supplying further resin under pressure to compensate for shrinkage of the composition, the epoxy resin containing coarse decorative particles therein, wherein the epoxy resin is introduced into the mould through a gap having a length which is 30 to 100% of that dimension of the moulded product being made which is adjacent to the gap and a width which is at least twice the maximum size of the decorative particles.
    Type: Grant
    Filed: June 14, 1994
    Date of Patent: June 4, 1996
    Assignee: Ciba-Geigy Corporation
    Inventors: Paul T. Wombwell, Philip D. Willis, Peter B. Ludman
  • Patent number: 5451362
    Abstract: The present invention provides a process for making a cured plastics moulding by introducing a pre-heated curable resin composition to a hotter mould which is at a temperature high enough to initiate curing of the resin, and supplying further resin under pressure to compensate for shrinkage of the composition, wherein the curable resin is an epoxy resin formulation comprising an epoxy resin containing more than one epoxide group per molecule on average, an acid anhydride hardener, an accelerator and a filler, the epoxy resin, hardener and accelerator being chosen so that the formulation is stable at 25.degree. C. for at least 14 days.
    Type: Grant
    Filed: November 18, 1993
    Date of Patent: September 19, 1995
    Assignee: Ciba-Geigy Corporation
    Inventors: Paul T. Wombwell, Richard J. Martin, Christopher H. Bull