Patents by Inventor Frans H. A. Vollebregt

Frans H. A. Vollebregt 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).

  • Phosphor composition comprising fine-grain and coarse-grain SiO.sub.2 particles
    Patent number: 6010779
    Abstract: A display screen having a phosphor coating comprising a phosphor composition of a phosphor provided with a coating which comprises one or more oxgyen compounds of the elements zinc, aluminium, magnesium, calcium and barium as well as colloidal SiO.sub. particles, said colloidal SiO.sub.2 particles being composed of SiO.sub.2 particles having an average size of 4 nm.ltoreq.d.ltoreq.30 nm, corresponding to a specific surface of 100 m.sup.2 /g.ltoreq.A.sub.s .ltoreq.550 nm m.sup.2 /g, and SiO.sub.2 particles having an average size of 50 nm.ltoreq.d.ltoreq.150 nm, corresponding to a specific surface of 25 m.sup.2 /g.ltoreq.A.sub.s .ltoreq.70 m.sup.2 /g.
    Type: Grant
    Filed: October 5, 1997
    Date of Patent: January 4, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Friederike Picht, Jacqueline Merikhi, Joachim Opitz, Hans-Otto Jungk, Jan W. G. de Bakker, Miguel Boutelje, Arlis G. Van Braam, Frans H. A. Vollebregt