Patent US4250131A successfully refreshed from Google Patents.
US4250131A
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Refractory inorganic oxide fibers
Assignee: Honeywell UOP LLC
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Filing: 1979-01-15
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Granted: 1981-02-10
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Expires: 1999-01-15
Abstract
Abstract A method of preparing refractory inorganic oxide fibers. A substantially liquid phase reaction mixture is formed consisting essentially of an inorganic oxide sol, e.g., an alumina sol, and a soluble, fiber-forming organic polymer, e.g., polyethylene oxide. The reaction mixture is concentrated, drawn into fibers and calcined.
Inventors
- 👤 Jay E. Sobel
- 👤 Vincent T. Brand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:13
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/62227; C04B35/62231; C04B35/62236; Y; Y10; Y10S; Y10S264/00; Y10S264/19
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
165 words
A method of preparing alumina fibers by the sequential steps of: (a) preparing a spinning solution consisting essentially of a fiberizable alumina sol by effecting a reduction in the acid anion concentration of an aqueous solution of a hydrolyzable acid salt of aluminum; (b) admixing therewith a fiber-forming organic polymer consisting essentially of fiber-forming organic polymers which are soluble in said sol and which are selected from the group consisting of polyurethane, polyethylene oxide and polyvinyl pyrrolidone, to form a substantially liquid phase mixture, said organic polymer comprising from about 0.5 to about 25 wt. % of said mixture; (c) concentrating said mixture to a viscosity of from about 1 to about 20,000 poise; and (d) thereafter drawing the concentrated mixture into fibers in an atmosphere characterized by a humidity of less than about 80% and a temperature of from about 5° to about 90° C., and calcining the resulting fibers in air at a temperature of from about 300° C. to about 1000° C.
Claim 2
Independent Claim
165 words
A method of preparing alumina fibers by the sequential steps of: (a) preparing a spinning solution consisting essentially of a fiberizable alumina sol by effecting a reduction in the acid anion concentration of an aqueous solution of a hydrolyzable acid salt of aluminum; (b) admixing therewith a fiber-forming organic polymer consisting essentially of fiber-forming organic polymers which are soluble in said sol and which are selected from the group consisting of polyurethane, polyethylene oxide and polyvinyl pyrrolidone, to form a substantially liquid phase mixture, said organic polymer comprising from about 0.5 to about 25 wt. % of said mixture; (c) concentrating said mixture to a viscosity of from about 1 to about 20,000 poise; and (d) thereafter drawing the concentrated mixture into fibers in an atmosphere characterized by a humidity of less than about 80% and a temperature of from about 5° to about 90° C., and calcining the resulting fibers in air at a temperature of from about 300° C. to about 1000° C.
Claim 3
Dependent Claim
58 words
The method of claim 1 further characterized in that said sol is an aluminum chloride sol prepared by effecting a reduction in the chloride anion concentration of an aqueous aluminum chloride solution, said sol containing from less than about 14 wt. % aluminum in from about 1:1 to about a 2:1 atom ratio with the chloride content thereof.
Claim 4
Dependent Claim
22 words
The method of claim 2 further characterized in that said aluminum sol contains from about 12 to about 14 wt. % aluminum.
Claim 5
Dependent Claim
40 words
The method of claim 1 further characterized in that said concentrated mixture is drawn into fibers in an atmosphere characterized by a relative humidity of less than about 10% and a temperature of from about 25° to about 90° C.
Claim 6
Dependent Claim
17 words
The method of claim 1 further characterized in that said organic polymer is a soluble polyethylene oxide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-10 | 1984-08-11 | 1985-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-10 | 1988-08-11 | 1989-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-10 | 1992-08-11 | 1993-02-10 | $7700.00 | Window Closed / Lapsed |