Method for synthesizing MgO--Al.sub.2 O.sub.3 --SiO.sub.2 glasses and ceramics

• US 4,604,118 A
• Filed: 08/13/1985
• Issued: 08/05/1986
• Est. Priority Date: 08/13/1985
• Status: Expired due to Fees

• Current Assignee: Corning Glass Works (Corning Incorporated)
• Original Assignee: Corning Glass Works (Corning Incorporated)
• Inventors: Bocko, Peter L., Wein, William J., Young, Charles E.
• Primary Examiner(s): Kellogg, Arthur
• Application Number:
  US06/765,199
• Time in Patent Office: 357 Days
• Field of Search: 65/3.12, 65/18.2, 65/18.3, 427/163, 427/252, 427/253
• US Class Current: 65/416
• CPC Class Codes: C03B 19/1415 Reactant delivery systems
• CPC Class Codes: C03B 2201/32 doped with aluminium C03B2201/36 takes precedence
• CPC Class Codes: C03B 2201/54 doped with beryllium, magnesium or alkaline earth metals
• CPC Class Codes: C03B 2207/06 Concentric circular ports
• CPC Class Codes: C03B 2207/08 Recessed or protruding ports
• CPC Class Codes: C03B 2207/12 Nozzle or orifice plates
• CPC Class Codes: C03B 2207/20 Specific substances in specified ports, e.g. all gas flows specified
• CPC Class Codes: C03B 2207/28 for different glass precursors, reactants or modifiers
• CPC Class Codes: C03B 2207/30 For glass precursor of non-standard type, e.g. solid SiH3F
• CPC Class Codes: C03B 2207/32 Non-halide
• CPC Class Codes: C03B 2207/86 by bubbling a gas through the liquid
• CPC Class Codes: C03B 2207/87 Controlling the temperature
• CPC Class Codes: C03B 2207/90 with vapour generated from solid glass precursors, i.e. by sublimation
• CPC Class Codes: C03B 37/01413 Reactant delivery systems C03B37/01807 takes precedence; devices therefor in general B01D1/00, B01J4/00
• CPC Class Codes: C03B 37/0142 Reactant deposition burners
• CPC Class Codes: C23C 16/401 containing silicon

Abstract

A vapor phase method for the synthesis of MgO--Al₂ O₃ --SiO₂ products, including MgO--Al₂ O₃ --SiO₂ glasses of optical quality, wherein SiCl₄, aluminum halide, and organometallic magnesium vapors are oxidized by flame oxidation and the oxides collected and sintered to glass or ceramic products, is described. A added shield gas stream is provided during flame oxidation of the vapors to reduce or prevent MgCl₂ by-product formation at the burner and in the product.

Claims

1. A method for synthesizing a vapor deposited MgO--Al₂ O₃ --SiO₂ oxide product which comprises the steps of:

(a) generating and supplying to a flame oxidation burner vapors of each of SiCl₄, an aluminum halide, and a magnesium organometallic compound, the aluminum halide vapors and magnesium organometallic vapors being supplied in separate vapor streams;

(b) injecting the vapors into an oxidizing combustion flame supported by the burner, the aluminum halide and organometallic magnesium vapors being expelled from the burners into the flame in separate vapor streams, and an interposing shield gas stream, free of both aluminum halide and magnesium organometallic vapors, being expelled into the flame between the streams containing the aluminum halide and magnesium organometallic vapors; and

(c) collecting the MgO--Al₂ O₃ --SiO₂ particulate oxidation product resulting from combustion of the vapors by the flame.

2. A method in accordance with claim 1 wherein the aluminum halide vapors consist essentially of AlCl₃.

3. A method in accordance with claim 2 wherein the interposing shield gas stream comprises SiCl₄ vapors.

4. A method in accordance with claim 2 wherein the interposing shield gas stream consists essentially of oxygen.

5. A method for synthesizing a vapor-deposited MgO--Al₂ O₃ --SiO₂ glass which comprises the steps of:

(a) generating and supplying to a flame oxidation burner vapors of each of SiCl₄, an aluminum halide, and a magnesium organometallic compound, the aluminum halide vapors and magnesium organometallic vapors being supplied in separate vapor streams;

(b) injecting the vapors into an oxidizing combustion flame supported by the burner, the aluminum halide and organometallic magnesium vapors being expelled from the burners into the flame in separate vapor streams, and an interposing shield gas stream, free of both aluminum halide and magnesium organometallic vapors, being expelled into the flame between the streams containing the aluminum halide and magnesium organometallic vapors; and

(c) collecting the MgO--Al₂ O₃ --SiO₂ particulate oxidation product resulting from combustion of the vapors by the flame; and

(d) heating the collected particulate MgO--Al₂ O₃ --SiO₂ oxidation product to sinter it to a clear glass.

6. A method in accordance with claim 5 wherein the aluminum halide consists essentially of AlCl₃.

7. A method in accordance with claim 6 wherein the interposing shield gas stream comprises SiCl₄ vapors.

8. A method in accordance with claim 6 wherein the interposing shield gas stream consists essentially of oxygen.