US4559191A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of ceramic fibers
Assignee: Celanese Corp
•
Filing: 1983-08-15
•
Granted: 1985-12-17
•
Expires: 2003-08-15
Abstract
Abstract This invention provides a multi-step process for the preparation of ceramic fibers, such as ferrimagnetic spinel fibers which are useful in electromagnetic interaction shielding applications. The process involves subjecting a ceramic powder-filled hollow organic fiber to isostatic pressing, and then pyrolyzing and sintering the compacted fiber to yield a ceramic fiber.
Inventors
- 👤 Richard M. Arons
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:55
CPC Classifications
B; B28; B28B; B28B3/00; B28B3/003; C; C04; C04B; C04B35/00; C04B35/622; C04B35/62227; C04B35/62231; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/34; H01F1/342; H01F1/344; Y; Y10; Y10S; Y10S264/00; Y10S264/19
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
92 words
A process for the production of a ceramic fiber which comprises (1) providing an organic polymer hollow core fiber which is filled with ceramic powder; (2) submerging the fiber in a fluid medium which is non-permeating and inert to the organic polymer sheath of the filled hollow core fiber, and applying hydrostatic pressure to the fiber to achieve isostatic compacting of the fiber and the ceramic powder filling content; and (3) heating the compacted fiber to pyrolyze the organic polymer content, and sinter the ceramic powder content to form a ceramic fiber.
Claim 2
Dependent Claim
92 words
A process for the production of a ceramic fiber which comprises (1) providing an organic polymer hollow core fiber which is filled with ceramic powder; (2) submerging the fiber in a fluid medium which is non-permeating and inert to the organic polymer sheath of the filled hollow core fiber, and applying hydrostatic pressure to the fiber to achieve isostatic compacting of the fiber and the ceramic powder filling content; and (3) heating the compacted fiber to pyrolyze the organic polymer content, and sinter the ceramic powder content to form a ceramic fiber.
Claim 3
Dependent Claim
22 words
A process in accordance with claim 1 wherein the organic polymer sheath of the hollow core fiber in step(1) comprises a polyamide.
Claim 4
Dependent Claim
22 words
A process in accordance with claim 1 wherein the organic polymer sheath of the hollow core fiber in step(1) comprises a polyester.
Claim 5
Dependent Claim
23 words
A process in accordance with claim 1 wherein the organic polymer sheath of the hollow core fiber in step(1) comprises a polyvinyl halide.
Claim 6
Dependent Claim
22 words
A process in accordance with claim 1 wherein the organic polymer sheath of the hollow core fiber in step(1) comprises a polyolefin.
Claim 7
Dependent Claim
23 words
A process in accordance with claim 1 wherein the organic polymer sheath of the hollow core fiber in step(1) comprises a cellulosic polymer.
Claim 8
Dependent Claim
15 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises alumina.
Claim 9
Dependent Claim
15 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises silica.
Claim 10
Dependent Claim
15 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises alumina-silica.
Claim 11
Dependent Claim
15 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises thoria-silica.
Claim 12
Dependent Claim
15 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises zirconia-silica.
Claim 13
Dependent Claim
15 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises alumina-chromia.
Claim 14
Dependent Claim
15 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises titania.
Claim 15
Dependent Claim
15 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises ferrite.
Claim 16
Dependent Claim
16 words
A process in accordance with claim 1 wherein the ceramic powder in step(1) comprises ferrimagnetic spinel.
Claim 17
Dependent Claim
13 words
A process in accordance with claim 1 wherein the fluid medium comprises water.
Claim 18
Dependent Claim
15 words
A process in accordance with claim 1 wherein the fluid medium comprises an organic liquid.
Claim 19
Dependent Claim
145 words
A process for the production of a ceramic fiber which comprises (1) forming a hollow core fiber which has a microporous organic polymer sheath and which has a lumen filled with a slurry of a ceramic powder in a liquid medium; (2) heating the fiber under conditions sufficient to purge the slurry liquid medium from within the lumen of the fiber, and subsequently heating the fiber under conditions sufficient to heat-seal the microporosity of the organic polymer sheath; (3) submerging the fiber in a fluid medium which is non-permeating and inert to the organic polymer sheath of the filled hollow core fiber, and applying hydrostatic pressure to the fiber to achieve isostatic compacting of the fiber and the ceramic powder filling content; and (4) heating the compacted fiber to pyrolyze the organic polymer content, and sinter the ceramic powder content to form a ceramic fiber.
Claim 20
Dependent Claim
145 words
A process for the production of a ceramic fiber which comprises (1) forming a hollow core fiber which has a microporous organic polymer sheath and which has a lumen filled with a slurry of a ceramic powder in a liquid medium; (2) heating the fiber under conditions sufficient to purge the slurry liquid medium from within the lumen of the fiber, and subsequently heating the fiber under conditions sufficient to heat-seal the microporosity of the organic polymer sheath; (3) submerging the fiber in a fluid medium which is non-permeating and inert to the organic polymer sheath of the filled hollow core fiber, and applying hydrostatic pressure to the fiber to achieve isostatic compacting of the fiber and the ceramic powder filling content; and (4) heating the compacted fiber to pyrolyze the organic polymer content, and sinter the ceramic powder content to form a ceramic fiber.
References Cited (Backward Citations)
US2517902A
Cited
US3110545A
Cited
US3133133A
Cited
US3136831A
Cited
US3607025A
Cited
US4008299A
Cited
US3705223A
Cited
US3939241A
Cited
US4225546A
Cited
US4250131A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-16 | 1989-06-17 | 1989-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-16 | 1993-06-17 | 1993-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-16 | 1997-06-17 | 1997-12-17 | $7700.00 | Window Closed / Lapsed |