US5094906A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceramic microtubular materials and method of making same
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1990-04-12
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Granted: 1992-03-10
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Expires: 2010-04-12
Abstract
Abstract Novel ceramic filamentary micro-tubular materials are described. An entirely, fluid-phase method has been devised for producing such interwoven ceramic filamentary tubular materials. The process depends for its success the ability to generate a three-dimensional random weave of ceramic tubes, with diameters in the range of about 0.01 to 2.0 microns, by forming carbon filaments by catalytic decomposition of a hydrocarbon feed, coating the filaments with a ceramic coating and then oxidizing the coated filaments to remove the carbon core leaving behind hollow ceramic micro-tubular filaments. The ceramic micro-tubular materials may be free-standing porous structures and may have a variety of uses as thermal insulators, catalyst supports, superconductor supports, filters or as reinforcements for composites.
Inventors
- 👤 Horst Witzke
- 👤 Bernard H. Kear
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:08
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2027; B01D39/2055; B01D39/2065; B01D39/2068; B01D39/2082; B01D39/2086; B01J; B01J35/00; B01J35/50; B01J35/58; B82; B82Y; B82Y30/00; C; C04; C04B; C04B20/00; C04B20/0048; C04B20/0056; C04B30/00; C04B30/02; C04B38/00; C04B38/06; C04B38/063; C04B38/0635; C04B38/0645; C04B38/065; C22; C22C; C22C47/00; C22C47/02; C22C47/04; C23; C23C; C23C16/00; C23C16/01; D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/127; D01F9/1271; B01D2239/00; B01D2239/04; B01D2239/0471; B01D2239/0492; B01D2239/06; B01D2239/0604; B01D2239/064; B01D2239/08; B01D2239/086; B01D2239/10; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/266; Y10T428/268; Y10T428/29; Y10T428/2913; Y10T428/2973; Y10T428/2975; Y10T442/00; Y10T442/60; Y10T442/603; Y10T442/605; Y10T442/608; Y10T442/614
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
85 words
A three-dimensional random weave of thin ceramic tubes produced by contacting a metallic catalyst for growing multi-directional carbon fibers with one or more gaseous hydrocarbons in a mold at a temperature sufficient to form filamentary carbon and insufficient to cause the pyrolytic deposition of carbon, depositing a conformal coating consisting of a ceramic or ceramic forming material on the carbon fibers, heating the coated fibers in an oxygen containing atmosphere for a time sufficient to volatilize, by oxidation, all or substantially all of the carbon.
Claim 2
Dependent Claim
85 words
A three-dimensional random weave of thin ceramic tubes produced by contacting a metallic catalyst for growing multi-directional carbon fibers with one or more gaseous hydrocarbons in a mold at a temperature sufficient to form filamentary carbon and insufficient to cause the pyrolytic deposition of carbon, depositing a conformal coating consisting of a ceramic or ceramic forming material on the carbon fibers, heating the coated fibers in an oxygen containing atmosphere for a time sufficient to volatilize, by oxidation, all or substantially all of the carbon.
Claim 3
Dependent Claim
19 words
A product of claim 1 wherein the conformal coating is deposited by chemical vapor deposition, electroplating or electroless deposition.
Claim 4
Dependent Claim
20 words
The product of claim 1 wherein a second conformal coating is deposited on the ceramic tubes after volatilizing the carbon.
Claim 5
Dependent Claim
24 words
A product of claim 1 wherein a liquid matrix material is introduced to the mold and converted to a solid after the volatilization step.
Claim 6
Dependent Claim
95 words
A three-dimensional random weave of thin ceramic tubes produced by a method comprising: contacting a finely divided metal catalyst for growing multi-directional carbon fibers with one or more gaseous hydrocarbons in a mold at a temperature from the dissociation temperature of the hydrocarbon to about 900° C., depositing a thin conformal ceramic coating of from about 0.1 micron to about 0.5 micron on the carbon fibers, heating the coated fibers in an oxygen containing atmosphere from a time sufficient to volatilize, by oxidation, all or substantially all of the carbon fibers to form ceramic tubes.
Claim 7
Dependent Claim
95 words
A three-dimensional random weave of thin ceramic tubes produced by a method comprising: contacting a finely divided metal catalyst for growing multi-directional carbon fibers with one or more gaseous hydrocarbons in a mold at a temperature from the dissociation temperature of the hydrocarbon to about 900° C., depositing a thin conformal ceramic coating of from about 0.1 micron to about 0.5 micron on the carbon fibers, heating the coated fibers in an oxygen containing atmosphere from a time sufficient to volatilize, by oxidation, all or substantially all of the carbon fibers to form ceramic tubes.
Claim 8
Dependent Claim
19 words
A product of claim 5 wherein the conformal coating is deposited by chemical vapor deposition, electroplating or electroless deposition.
Claim 9
Dependent Claim
20 words
A product of claim 5 wherein a second conformal coating is deposited on the ceramic tubes after volatilizing the carbon.
Claim 10
Dependent Claim
20 words
A product of claim 7 wherein the second conformal coating is carbon, a metal, a ceramic compound or mixture thereof.
Claim 11
Dependent Claim
20 words
A product of claim 5 wherein a liquid matrix material is introduced to the mold and converted to a solid.
Claim 12
Dependent Claim
19 words
A product of claim 9 wherein the matrix material is a polymer, elastomer, epoxy resin, metal, alloy or ceramic.
Claim 13
Dependent Claim
22 words
A product of claim 9 wherein the resulting structure has at least one section with a thickness of less than one millimeter.
Claim 14
Dependent Claim
89 words
The three-dimensional random weave of thin ceramic tubes produced by the method which comprises: contacting a finely divided catalyst consisting of solid solution of nickel and copper for growing multidirectional carbon fibers with a C 2 hydrocarbon gas in a mold at a temperature from about 450° C. to 750° C., depositing a thin conformal ceramic coating on the fibers, heating the coated fibers in an oxygen containing atmosphere from a time sufficient to volatilize, by oxidation, all or substantially all of the carbon fibers to form ceramic tubes.
Claim 15
Dependent Claim
89 words
The three-dimensional random weave of thin ceramic tubes produced by the method which comprises: contacting a finely divided catalyst consisting of solid solution of nickel and copper for growing multidirectional carbon fibers with a C 2 hydrocarbon gas in a mold at a temperature from about 450° C. to 750° C., depositing a thin conformal ceramic coating on the fibers, heating the coated fibers in an oxygen containing atmosphere from a time sufficient to volatilize, by oxidation, all or substantially all of the carbon fibers to form ceramic tubes.
Claim 16
Dependent Claim
20 words
The method of claim 12 wherein the conformal coating has a thickness of about 0.01 micron to about 0.5 micron.
Claim 17
Dependent Claim
21 words
The method of claim 12 wherein a second conformal coating is deposited on the ceramic tubes after volatilizing the carbon fibers.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1995-03-10 | 1995-09-09 | 1996-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-10 | 1999-09-09 | 2000-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-10 | 2003-09-09 | 2004-03-10 | $7700.00 | Window Closed / Lapsed |