# US 2015/0307406 A1 · Coloured technical ceramic bodies and method for preparing the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2015/0307406 A1 - Document ID: US20150307406A1 - Status: Published application - Kind: A1 - Application number: 14/647,642 - Filed: 2013-12-20 - Published: 2015-10-29 - Earliest claimed: 2012-12-21 - Assignees: Rolex SA - Applicants: Rolex S.A. - Inventors: Ollivier PUJOL; Carine BIENVENU - Web page: https://patentgrep.com/patent/US20150307406A1 ## CPC - C04B 35/64: Burning or sintering processes (C04B33/32 takes precedence {; powder metallurgy B22F}) - C04B 35/10: based on aluminium oxide - C04B 41/009: {characterised by the material treated} - C04B 41/5007: {with salts or salty compositions, e.g. for salt glazing (C04B41/5006 takes precedence)} - C04B 41/85: with inorganic materials - G04B 37/226: {coated with a metallic layer} - C04B 2111/82: Coloured materials - C04B 2235/9661: Colour - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - G04B: MECHANICALLY-DRIVEN CLOCKS OR WATCHES; MECHANICAL PARTS OF CLOCKS OR WATCHES IN GENERAL; TIME PIECES USING THE POSITION OF THE SUN, MOON OR STARS (spring- or weight-driven mechanisms in general F03G; electromechanical clocks or watches G04C; electromechanical clocks with attached or built-in means operating any device at pre-selected times or after predetermined time intervals G04C23/00; clocks or watches with stop devices G04F7/08) ## Abstract The present invention relates to novel technical ceramic bodies and a method for preparing these technical ceramic bodies. The method of the invention for the production of a coloured technical ceramic body comprises the following steps: providing a composition comprising alumina, at least one pigment component and optionally binder materials, preparing a green body from this composition, optionally debinding the green body, thereafter subjecting the green body to a treatment with a metal-containing preparation as a further pigment component, and sintering the treated green body. The coloured technical ceramic body of the present invention consists of alumina as a technical ceramic material, the technical ceramic body comprising a first coloured area and a second coloured area of a different colour, whereby the first coloured area contains a first pigment component, and the second coloured area contains a second pigment component in combination with the first pigment component. ## Claims ### Claim 1 Method for the production of a coloured technical ceramic body, comprising the following steps: providing a composition comprising alumina as the major component, at least one pigment component and optionally binder materials, preparing a green body from this composition, optionally debinding the green body, thereafter subjecting the green body to a treatment with a metal-containing preparation as a further pigment component, and sintering the treated green body. ### Claim 2 (depends on 1) The method of claim 1, wherein the composition comprises the binder materials and the method includes the debinding step which consists in treating the green body with heat, or in treating the green body with an aqueous solution and subsequently drying the treated green body. ### Claim 3 (depends on 1) The method of claim 1 wherein the at least one pigment component is a metal selected from the group consisting of chromium, nickel, manganese, vanadium, titanium and iron which metal is present in substitution at one of the alumina lattice sites. ### Claim 4 (depends on 1) The method of claim 1 wherein the composition which is provided in the first step contains magnesium in an amount of 0.0008 to 5% by weight, calculated as the amount of magnesia in the composition. ### Claim 5 (depends on 1) The method of claim 1 wherein the composition which is provided in the first step consists of: 0.4-5% by weight of at least one of Cr, Co, Ni, Mn, V, Ti or Fe 0.0008-0.5% by weight of Mg, 0.05-6% by weight of a lanthanide element, and up to 100% weight alumina, these amounts being calculated on the basis of the oxides of the elements which are present. ### Claim 6 (depends on 1) The method of claim 1, the composition consisting of 1.0-3.0 wt-% of Cr203, 0.05-0.5 wt-% of MgO, 0.1-5 wt-% of Er203 and the remainder of alumina. ### Claim 7 (depends on 1) The method of claim 1, wherein the treatment with heat for debinding the green body is conducted at a temperature in the range of 700 to 1200° C. ### Claim 8 (depends on 1) The method of claim 1, whereby the green body is subjected partly to treatment with the metal-containing preparation. ### Claim 9 (depends on 1) The method of claim 1, wherein the treatment with the metal-containing preparation is an impregnation with a solution of at least one metallic salt as a further pigment component, which is followed by drying of the impregnated body. ### Claim 10 (depends on 9) The method of claim 9, wherein the impregnating solution is a solution of at least one salt of a metal selected from the group consisting of Co, Cu, Cr, Fe, Mg, Mn, Mo, Ni, Ti, and Zn in water and/or if appropriate at least one organic solvent. ### Claim 11 (depends on 9) The method of claim 9, wherein the drying step after the impregnation is conducted at ambient temperature during 12 to 24 hours, or at 60-100° C. during 1 to 60 minutes. ### Claim 12 (depends on 1) The method of claim 1, wherein the green body which has been treated with a metal-containing preparation as a further pigment component and has been optionally dried is sintered at a temperature of between 1250 and 1700° C., preferably at a temperature between 1550 and 1670° C. ### Claim 13 (depends on 1) The method of claim 1, wherein the coloured technical ceramic body is a watch component, in particular a watch bezel or a watch case. ### Claim 14 A coloured technical ceramic body, comprising as a major component of its composition alumina as a technical ceramic material, the technical ceramic body comprising a first coloured area and a second coloured area of a different colour, whereby the first coloured area contains a first pigment component, and the second coloured area contains a second pigment component in combination with the first pigment component. ### Claim 15 (depends on 14) The coloured technical ceramic body according to claim 14, wherein the first pigment component is Cr present in substitution in the alumina crystal lattice and the second pigment component is a complex inorganic pigment compound showing a spinel crystal structure of space group Fd-3m. ### Claim 16 (depends on 14) The coloured technical ceramic body according to claim 14, wherein the first coloured area has a red colour and the second coloured area has a blue colour. ### Claim 17 (depends on 15) The coloured technical ceramic body according to claim 15 which is a watch bezel. ### Claim 18 (depends on 10) The method of claim 10, wherein the drying step after the impregnation is conducted at ambient temperature during 12 to 24 hours, or at 60-100° C. during 1 to 60 minutes.