Patents by Inventor Lindsay Kilmurray, deceased

Lindsay Kilmurray, deceased 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).

  • Process for producing transparent pigmentary quinacridones by acid swelling of premilled subpigmentary quinacridones in the presence of an organic liquid
    Patent number: 5919299
    Abstract: A process for preparing transparent, pigmentary quinacridone compounds and solid solutions thereof comprises combining a premilled, sub-pigmentary powder containing at least one unsubstituted or substituted quinacridone or a derivative thereof with a sufficient amount of moderately concentrated sulfuric acid to form a slurry, then agitating this slurry in the presence of an organic liquid which is immiscible or only partially miscible with the slurry and which is effective in deagreggating and improving the crystallinity of the pigment, for an effective length of time to convert the sub-pigmentary unsubstituted or substituted quinacridone or solid solution thereof to a transparent, pigmentary form.
    Type: Grant
    Filed: December 3, 1997
    Date of Patent: July 6, 1999
    Assignee: Ciba Specialty Chemicals Corporation
    Inventors: Lindsay Kilmurray, deceased, Edward E. Jaffe