Patents by Inventor Paul Viroux

Paul Viroux 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).

  • High-purity polymer granules and method for the production thereof
    Patent number: 6720406
    Abstract: A process for producing polymer pellets is disclosed. The process that is particular suitable for making polycarbonate pellets entails extruding a polymer melt, cooling the extrudate by contacting it with a cooling fluid and pelletizing the solidified polymer. The process is characterized in that the cooling fluid has a solids particle content of at most 10 ppm.
    Type: Grant
    Filed: April 30, 2002
    Date of Patent: April 13, 2004
    Assignees: Bayer Aktiengesellschaft, Bayer Antwerpen N.V.
    Inventors: Thomas Elsner, Jürgen Heuser, Christian Kords, Steffen Kühling, Paul Viroux
  • Polycarbonate substrates
    Patent number: 6710154
    Abstract: A method for producing polycarbonate based on 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexanone and 4,4-(metaphenylene diisopropyl) diphenol is disclosed. The method is characterized in that the recovery and/or further processing of the polycarbonate is performed at temperatures below 290° C. The polycarbonate thus produced has high purity and high transmission and is suitable for the manufacture of optical data stores.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: March 23, 2004
    Assignee: Bayer Aktiengesellschaft
    Inventors: Tony van Osselaer, Steffen Kühling, Paul Viroux, Hugo Plompen, Richard Vansant
  • Polycarbonate substrates
    Publication number: 20030004297
    Abstract: The invention relates to a method for producing polycarbonate having a high purity and an extremely high transmittance especially at short wavelengths. The inventive polycarbonate is produced on the basis of 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexanone and 4,4-(meta-phenylendiisopropyl)-diphenol. The invention also relates to the polycarbonate obtained, to its use in the production of optical memories and to optical memories produced according to the invention.
    Type: Application
    Filed: July 10, 2002
    Publication date: January 2, 2003
    Inventors: Tony van Osselaer, Steffen Kuhling, Paul Viroux, Hugo Plompen, Richard Vansant