The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 11, 1993
Filed:
Nov. 25, 1991
Tom A Kavassalis, Waterdown, CA;
Francoise M Winnik, Toronto, CA;
Xerox Corporation, Stamford, CT (US);
Abstract
Disclosed is a composition which comprises silica particles containing a water soluble dye entrapped therein, said silica particles being coated with a surfactant. The particles can be prepared by a process which comprises preparing a mixture of a surfactant and an organic solvent immiscible with water and capable of forming a stable microemulsion with water, adding to the mixture a solution of a water-soluble dye, a hydrolyzing reagent, and water to form a microemulsion of water domains within a continuous phase of the organic solvent, and adding to the microemulsion a tetraalkoxysilane, wherein the tetraalkoxysilane reacts with the hydrolyzing agent to form in each water domain a silica particle containing the water-soluble dye and coated with the surfactant. The particles are useful as colorants for various organic materials, such as dry electrostatic toners, liquid electrostatic toners, plastics, oil based inks, hot melt ink jet inks, and the like.