# US 5,350,927 A · Radiation emitting ceramic materials and devices containing same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,350,927 A - Document ID: US5350927A - Status: Granted - Kind: A - Application number: 07/900,228 - Filed: 1992-06-17 - Granted: 1994-09-27 - Earliest claimed: 1992-06-17 - Assignees: Mitech Scientific Corp. - Inventors: Roustam K. Rakhimov; Elena V. Kim - Web page: https://patentgrep.com/patent/US5350927A ## CPC - A61L 2/08: Radiation - C04B 35/185: Mullite {3Al2O3-2SiO2} - C04B 35/42: based on chromites (C04B35/047 and C04B35/105 take precedence) - F26B 3/30: from infrared-emitting elements {(by radiation emanating from passages containing heated fluids other than combustion gases F26B23/10)} - H05B 3/141: {Conductive ceramics, e.g. metal oxides, metal carbides, barium titanate, ferrites, zirconia, vitrous compounds} - H05B 3/64: using ribbon, rod, or wire heater - A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K) - 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 - F26B: DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM (drying devices for combines A01D41/133; racks for drying fruit or vegetables A01F25/12; drying foodstuffs A23; drying hair A45D20/00; body-drying implements A47K10/00; drying household articles A47L; drying gases or vapours B01D; chemical or physical processes for dewatering or like separating liquids from solids B01D43/00; centrifugal apparatus B04; drying ceramics C04B33/30; drying yarns or fabrics in association with some other form of treatment D06C; drying frames for laundry without heating or positive air circulation, domestic laundry-or spin-driers, wringing or hot pressing laundry D06F; furnaces, kilns, ovens F27) - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract The disclosed invention is directed to novel ceramic compositions, and to stabilizer compositions for use with those ceramic compositions. The ceramic materials are formed of rare earth chromium oxides that include a novel combination of stabilizing compounds. Also, dryer or sterilizer devices which incorporate these ceramic compositions for generating infrared radiation for drying or sterilizing various articles. ## Claims ### Claim 1 An apparatus for drying or sterilizing articles comprising: a chamber for receiving articles to be dried or sterilized; means for providing energy within the chamber; and a first ceramic material comprising a rare earth chromium oxide composition and a stabilizing composition comprising sufficient amounts of an alkaline earth spinel and an alkaline earth chromate which, in combination, stabilize the rare earth chromium oxide composition, wherein said ceramic material is associated with the chamber for receiving and absorbing energy from the providing means and for emitting infrared radiation of one or more selective wavelengths which radiation is directed toward the articles for drying or sterilization thereof. ### Claim 2 (depends on 1) The apparatus of claim 1 wherein the providing means includes an energizable element which is operatively associated with the first material such that a substantial portion of the energy generated by the element is received and absorbed by the first ceramic material. ### Claim 3 (depends on 1) The apparatus of claim 1 wherein the first ceramic material is positioned adjacent at least a portion of the element such that a substantial portion of the energy generated by the providing means is received and absorbed by the first ceramic material. ### Claim 4 (depends on 1) The apparatus of claim 1 wherein the providing means comprises a plurality of energizable elements each having an energy emitting surface, and the first ceramic material is positioned adjacent a portion of the energy emitting surface of each of said elements within the chamber. ### Claim 5 (depends on 4) The apparatus of claim 4 wherein the first ceramic material is concentric around at least one of the elements. ### Claim 6 (depends on 4) The apparatus of claim 4 wherein the first ceramic material forms a concentric tube around each element. ### Claim 7 (depends on 6) The apparatus of claim 6 which further comprises means for supporting the articles to be dried or sterilized. ### Claim 8 (depends on 1) The apparatus of claim 1 which further comprises a second ceramic material associated with the chamber for emitting infrared radiation of one or more selective wavelengths wherein said radiation is different from radiation emitted by the first ceramic material and is directed toward the articles for drying or sterilization thereof. ### Claim 9 (depends on 8) The apparatus of claim 8 wherein the second ceramic material is associated with the chamber for receiving and absorbing infrared radiation from the first ceramic material. ### Claim 10 (depends on 9) The apparatus of claim 9 wherein the first ceramic material is positioned adjacent at least a portion of the providing means such that a substantial portion of the energy generated by the providing means is received and absorbed by the first ceramic material, and the second ceramic material is positioned adjacent at least a portion of the first ceramic material such that a portion of the infrared radiation emitted by the first ceramic material is received and absorbed by the second ceramic material. ### Claim 11 (depends on 10) The apparatus of claim 10 wherein the providing means comprises a plurality of energizable elements each having an energy emitting surface, the first ceramic material is positioned adjacent a substantial portion of the energy emitting surface of each element and the second ceramic material is positioned adjacent a substantial portion of the first ceramic material. ### Claim 12 (depends on 11) The apparatus of claim 11 wherein the first ceramic material is concentric around at least one of the elements and the second ceramic material is concentric around the first ceramic material. ### Claim 13 (depends on 11) The apparatus of claim 11 wherein the first ceramic material forms a concentric tube around each element and the second ceramic material forms a concentric tube around each tube of first ceramic material. ### Claim 14 (depends on 9) The apparatus of claim 9 which further comprises means for supporting the elements to be dried or sterilized, and wherein the providing means comprises a plurality of energizable elements each having an energy emitting surface, the first ceramic material is positioned adjacent a substantial portion of the energy emitting surface of each element within the chamber, and the second ceramic material is positioned within the chamber to receive a substantial portion of the infrared radiation emitted from the first ceramic material. ### Claim 15 (depends on 14) The apparatus of claim 14 wherein the second ceramic material is configured in the form of a plate and is positioned near the energizable elements to receive substantially all infrared radiation emitted from the first ceramic material. ### Claim 16 (depends on 2) The apparatus of claim 2 wherein the energizable element comprises at least one of either a halogen lamp or a high resistance wire coil within a glass tube. ### Claim 17 (depends on 1) The apparatus of claim 1 which further comprises a second ceramic material associated with the chamber for emitting infrared radiation of one or more selective wavelengths which radiation is different from that emitted by the first ceramic material and is directed toward the articles for drying or sterilization thereof. ### Claim 18 (depends on 17) The apparatus of claim 17 which further comprises means for supporting the articles to be dried or sterilized, and wherein the providing means comprises a plurality of energizable elements, each having an energy emitting surface, the first ceramic material is positioned adjacent a substantial portion of the energy emitting surface of each of said elements within the chamber, and the second ceramic material is positioned within the chamber to receive a substantial portion of the infrared radiation emitted from the first ceramic material. ### Claim 19 An apparatus for drying or sterilizing articles comprising: a chamber for receiving articles to be dried or sterilized; means for providing energy within the chamber; and a first ceramic material comprising a rare earth chromium oxide and a stabilizing composition comprising sufficient amounts of an alkaline earth spinel and an alkaline earth chromate which, in combination, stabilize the rare earth chromium oxide composition, and at least one of (a) an oxide of zirconium or hafnium in an amount of about 0.5 to 5 weight percent of the ceramic composition, (b) a chromate of yttrium, scandium, ytterbium, or terbium in an amount of about 0.5 to 5 weight percent of the ceramic composition, or (c) an oxide of cerium, dysprosium, lutetium, or europium in an amount of about 0.1 to 1 weight percent of the ceramic composition, said ceramic material associated with the chamber for receiving and absorbing energy from the providing means and for emitting infrared radiation of one or more selective wavelengths which radiation is directed toward the articles for drying or sterilization thereof. ### Claim 20 An apparatus for drying or sterilizing articles comprising: a chamber for receiving articles to be dried or sterilized; means for providing energy within the chamber; a first ceramic material comprising rare earth chromium oxide and a stabilizing composition comprising sufficient amounts of an alkaline earth spinel and an alkaline earth chromate which, in combination, stabilize the rare earth chromium oxide composition, the ceramic material associated with the chamber for receiving and absorbing energy from the providing means and for emitting infrared radiation of one or more selective wavelengths which radiation is directed toward the articles for drying or sterilization thereof; and a second ceramic material comprising Cr.sub.2 O.sub.3 which includes SiO.sub.2, Fe.sub.2 O.sub.3 and one or more of the following additives: Al.sub.2 O.sub.3, CuO, CaO or MgO, wherein said second ceramic material is associated with the chamber for receiving and absorbing infrared radiation from the first ceramic material and for emitting infrared radiation of one or more selective wavelengths, which radiation is different from that emitted by the first ceramic material and is directed toward the articles for drying or sterilization thereof. ### Claim 21 (depends on 20) The apparatus of claim 20 wherein the second ceramic material comprises SiO.sub.2 in an amount of about 10 to 28 weight percent, Fe.sub.2 O.sub.3 in an amount of about 15 to 35 weight percent, and the balance essentially Cr.sub.2 O.sub.3 with one or more of the following additives: Al.sub.2 O.sub.3 in an amount of about 0.5 to 3.5 weight percent, CuO in an amount of about 0.1 to 2 weight percent; CaO in an amount of about 0.5 to 15 weight percent, and MgO in an amount of about 0.1 to 3 weight percent. ### Claim 22 An apparatus for drying or sterilizing articles comprising: a chamber for receiving articles to be dried or sterilized; means for providing energy within the chamber; and a ceramic material comprising Cr.sub.2 O.sub.3 which includes SiO.sub.2, Fe.sub.2 O.sub.3 and one or more of the following additives: Al.sub.2 O.sub.3, CuO, CaO or MgO, wherein said ceramic material is associated with the chamber for receiving and absorbing energy from the providing means and for emitting infrared radiation of one or more selective wavelengths which radiation is directed toward the articles for drying or sterilization thereof. ### Claim 23 (depends on 22) The apparatus of claim 22 wherein the ceramic material comprises SiO.sub.2 in an amount of about 10 to 28 weight percent, Fe.sub.2 O.sub.3 in an amount of about 15 to 35 weight percent, and the balance essentially Cr.sub.2 O.sub.3 with one or more of the following additives: Al.sub.2 O.sub.3 in an amount of about 0.5 to 3.5 weight percent, CuO in an amount of about 0.1 to 2 weight percent; CaO in an amount of about 0.5 to 15 weight percent, and MgO in an amount of about 0.1 to 3 weight percent.