US4125406A
Expired / Lapsed
US
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Alumina-chromia-metal (IV) oxide refractory fibers having a microcrystalline phase
Assignee: 3M Co
•
Filing: 1974-09-03
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Granted: 1978-11-14
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Expires: 1994-09-03
Abstract
Abstract Refractory fibers having a composition of 10-75% Al 2 O 3 , 1-30% Cr 2 O 3 and 10-75% metal (IV) oxide selected from at least one of silica, titania, zirconia, and tin oxide and having at least one microcrystalline phase therein may remain strong, flexible, and continuous at temperatures of 1300° to 1500°C and beyond.
Inventors
- 👤 Harold G. Sowman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:23
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/62227; C04B35/62231; C04B35/62236; C04B35/01; C04B35/42
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
66 words
A shaped, fired, transparent refractory fiber having at least one microcrystalline phase, the fiber comprising a composition of 10-75% Al 2 O 3 , 1-30% Cr 2 O 3 and 10-75% RO 2 wherein R is selected from silicon, titanium, zirconium or tin wherein the fibers having more than 60% Al 2 O 3 have a specific surface area of less than 30 m 2 /g.
Claim 2
Dependent Claim
66 words
A shaped, fired, transparent refractory fiber having at least one microcrystalline phase, the fiber comprising a composition of 10-75% Al 2 O 3 , 1-30% Cr 2 O 3 and 10-75% RO 2 wherein R is selected from silicon, titanium, zirconium or tin wherein the fibers having more than 60% Al 2 O 3 have a specific surface area of less than 30 m 2 /g.
Claim 3
Dependent Claim
12 words
A fabric material comprising a multiplicity of the fibers of claim 1.
Claim 4
Dependent Claim
33 words
The fiber of claim 1 wherein the major microcrystalline phase is a solid solution of Al 2-x Cr x O 3 wherein x has a value greater than 0 and less than 2.
Claim 5
Dependent Claim
16 words
The fiber of claim 1 wherein the major microcrystalline phase is Cr 2 O 3 .
Claim 6
Dependent Claim
15 words
The fiber of claim 1 having a microcrystalline phase of Al 2 O 3 .
Claim 7
Dependent Claim
26 words
The fiber of claim 1 which is transparent and comprises 55-75% Al 2 O 3 , 1-10% Cr 2 O 3 and 15-44% RO 2 .
Claim 8
Dependent Claim
22 words
The fiber of claim 1 comprising 10-30% Cr 2 O 3 , 20-65% Al 2 O 3 and 15-60% RO 2 .
Claim 9
Dependent Claim
15 words
The fiber of claim 1 having two distinct zones identifiable as a sheath and core.
Claim 10
Dependent Claim
10 words
The fiber of claim 1 wherein RO 2 is silica.
Claim 11
Dependent Claim
10 words
The fiber of claim 7 wherein RO 2 is silica.
Claim 12
Dependent Claim
70 words
A process for forming a refractory fiber which comprises extruding a viscous concentrate to a fiber form having a metal oxide equivalent composition of: 10 - 75% Al 2 O 3 1 - 30% cr 2 O 3 , and 10 - 75% RO 2 wherein R is selected from silicon, titanium, zirconium or tin, and, firing said fiber form to develop a transparent fiber having a microcrystalline species therein.
Claim 13
Dependent Claim
70 words
A process for forming a refractory fiber which comprises extruding a viscous concentrate to a fiber form having a metal oxide equivalent composition of: 10 - 75% Al 2 O 3 1 - 30% cr 2 O 3 , and 10 - 75% RO 2 wherein R is selected from silicon, titanium, zirconium or tin, and, firing said fiber form to develop a transparent fiber having a microcrystalline species therein.
Claim 14
Dependent Claim
13 words
The process of claim 11 wherein the fiber form is fired in air.
Claim 15
Dependent Claim
17 words
The process of claim 11 wherein the fiber form is dried to a green fiber before firing.
Claim 16
Dependent Claim
10 words
The process of claim 11 wherein RO 2 is silica.
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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) | 1981-11-13 | 1982-05-15 | 1982-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-13 | 1986-05-15 | 1986-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-13 | 1990-05-15 | 1990-11-14 | $7700.00 | Window Closed / Lapsed |