US4018858A
Expired / Lapsed
US
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Method of manufacturing refractory articles
Assignee: Zirconal Processes Ltd
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Filing: 1975-03-24
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Granted: 1977-04-19
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Expires: 1995-03-24
Abstract
Abstract The invention concerns the binding of refractory powders into self-supporting "green" shapes which are fired to provide refractory objects. In accordance with the invention the binders are based on zirconium salts and include a dispersion of calcined magnesia in a mixture of water and a polyhydric alcohol. The magnesia reacts with the zirconium salt to form zirconium oxide/hydroxide which gells hard. In order to control the speed of gelling a separate gell time delaying agent is also optionally included.
Inventors
- 👤 Ian Richard Walters
- 👤 Harold Garton Emblem
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:57
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/632; C04B35/6325; C04B35/01; C04B35/48; C04B35/481; C04B35/6303; C04B35/634
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
144 words
A method of manufacturing refractory articles comprising the steps of: a. preparing a gellable, liquid binder for a refractory powder by mixing an aqueous solution of a zirconium salt and a dispersion of calcined magnesia powder in a mixture of from 20 to 90% water and from 80 to 10% of a polyhydric alcohol; b. mixing a refractory powder with the liquid binder to form a liquid, flowable slurry thereof, the amounts of zirconium salt, magnesium powder and refractory powder being such that the slurry will set to a coherent state upon standing; c. pouring the slurry while liquid and flowable into a mold; d. allowing the slurry in the mold to set to form a coherent green shape; and e. removing the green shape from the mold, drying the green shape, and firing the dried green shape to form a sintered refractory mass.
Claim 2
Independent Claim
144 words
A method of manufacturing refractory articles comprising the steps of: a. preparing a gellable, liquid binder for a refractory powder by mixing an aqueous solution of a zirconium salt and a dispersion of calcined magnesia powder in a mixture of from 20 to 90% water and from 80 to 10% of a polyhydric alcohol; b. mixing a refractory powder with the liquid binder to form a liquid, flowable slurry thereof, the amounts of zirconium salt, magnesium powder and refractory powder being such that the slurry will set to a coherent state upon standing; c. pouring the slurry while liquid and flowable into a mold; d. allowing the slurry in the mold to set to form a coherent green shape; and e. removing the green shape from the mold, drying the green shape, and firing the dried green shape to form a sintered refractory mass.
Claim 3
Dependent Claim
48 words
The method of claim 1 wherein a substance controlling the speed of gelling is added to said liquid binder, said substance being chosen from the group consisting of magnesium salt, ammonium lactate, a compound which in solution provides a dipolar ion (Zwitterion), a polyhydric alcohol and a monosaccharide.
Claim 4
Dependent Claim
25 words
The method of claim 1 wherein said magnesia is light magnesia having a bulk density such that 20 grams occupies at least 150 cubic centimeters.
Claim 5
Dependent Claim
27 words
The method of claim 1 wherein said zirconium salt is selected from the group consisting of a zirconium acetate, zirconium oxychloride, zirconium formate, and ammonium zirconium carbonate.
Claim 6
Dependent Claim
12 words
The method of claim 1 where said zirconium salt is zirconium acetate.
Claim 7
Dependent Claim
11 words
The method of claim 1 wherein said polyhydric alcohol is glycerol.
Claim 8
Dependent Claim
12 words
The method of claim 1 wherein said polyhydric alcohol is ethylene glycol.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-04-18 | 1980-10-18 | 1981-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-18 | 1984-10-18 | 1985-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-18 | 1988-10-18 | 1989-04-19 | $7700.00 | Window Closed / Lapsed |