Patents Assigned to Ciba Specialty Chemicals Holding, Inc.
  • Patent number: 5718753
    Abstract: The instant invention relates to a process for the production of colored metallic pigments, as well as these colored metallic pigments themselves, their use to color high molecular weight organic material in the mass and compositions or masterbatches containing them.The colored metallic pigment consists essentially of multiple loose particles of 0.1-1000 .mu.m size each, said particles comprising a core of a transition metals, metalloid or alloy, preferably an aluminum flake, and a very fine, substantially continuous, uniform and homogeneous layer of organic pigment particles which is directly in contact with the metallic core. The core may be superficially oxidized.The colored metallic pigment is prepared by a vacuum deposition process, said process being performed in an apparatus constructed, modified or charged in such a way that the organic pigment gas flows toward the metallic core.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: February 17, 1998
    Assignee: Ciba Specialty Chemicals Holding, Inc.
    Inventors: Masakazu Suzuki, Hiroshi Nakaminami, Seiji Homma
  • Patent number: 5718998
    Abstract: The invention is related to an electrophotographic photoreceptor, its preparation, and its use in electrophotography. The instant photoreceptor comprises a conductive substrate and a photosensitive layer containing an organic pigment as a charge generating material, wherein said organic pigment is formed from a soluble organic pigment precursor.Particularly suitable soluble pigment precursors are of formulae (I) or (XIV), ##STR1## wherein A represents a chromophore residue which is a perylene, quinacridone, dioxazine, anthraquinone, azo, phthalocyanine, isoindolinone, isoindoline, indigo, quinophthalone or pyrrolopyrrole with 1 to 5 N atoms bound to the D.sub.1 and D.sub.2 groups, whereby each N atom of A is independently from the other bound to 0, 1 or 2 groups D.sub.1 or D.sub.2 ;D.sub.1 and D.sub.2 are independently a group represented by the general formula ##STR2## x is an integer from 0 to 4; L.sub.1 and L.sub.2 are independently from one other halogen, alkoxy or amino groups, andM.sub.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: February 17, 1998
    Assignee: Ciba Specialty Chemical Holding, Inc.
    Inventors: Ryuichi Takahashi, Kazuyo Yamamoto, Abul Iqbal, Zhimin Hao