Patent ID: 6114054
Filing Date: 2000-09-05
Classification: C04B

Abstract:
A method for coloring a surface of a ceramic mass to produce a colored ceramic body, the method comprising:(a) providing a host lattice material comprised of a colorless metal oxide compound which crystallizes when fired into one of a spinel lattice or a rutile lattice and which may be water soluble;(b) providing an aqueous coloring solution comprising water; a first water soluble compound including a metal ion which is one of a two-valent metal ion or a three-valent metal ion and which colors the host lattice material; and a second water soluble compound including a metal ion which is one of a five-valent metal ion or six-valent metal ion and which provides electrostatic balance;(c) treating the surface of the ceramic mass by one of:i. working a fine powder of the colorless metal oxide into the ceramic mass and applying the aqueous coloring solution onto at least one surface of the ceramic mass, ori.i. adding a water soluble colorless metal oxide compound to the aqueous coloring solution in an amount effective to form a mixture having a preselected viscosity and applying this mixture to the surface of the ceramic mass;(d) drying the solution; and(e) firing the ceramic body at a temperature ranging from 300 to 1400.degree. C. for a duration ranging from 0.5 to 5 hours to generate a mixed-phase pigment in the surface of the ceramic mass and thereby color the surface of the ceramic mass and produce the colored ceramic body.