Patents Assigned to ColoRSil B.V.
  • Patent number: 5275649
    Abstract: A new doped zirconium mixed silicate pigment has been found, having a particle size D.sub.50 of 3 .mu.m or less and a molar ratio of zirconium dioxide/silicon dioxide that deviates from the stoichiometric ratio and is in the range of 1/1.5-1/36. This new pigment is doped with 1-25% by weight of a color-providing metal oxide an exhibits great color strength as well as good thermostability. The new pigment, which has a very high particle fineness, can be used for ceramic applications and for coloring glass, but is also particularly suitable for applications outside the ceramic field, in particular as a colorant in plastics, rubber, paint, printing ink and cosmetic products. Further, a similar new doped zirconium silicate pigment has been found, which, however, has a D.sub.50 particle size that is greater than 3 .mu.m, the molar ratio of zirconium dioxide/silicon dioxide being in the range of 1/4.9-1/36. The last-mentioned pigment is very suitable to be incorporated into glass.
    Type: Grant
    Filed: February 18, 1993
    Date of Patent: January 4, 1994
    Assignee: ColoRSil B.V.
    Inventors: Erich A. E. Linke, Cornelis H. Zwart, Adrianus D. Smout