US4070514A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of fabricating graphite for use as a skeletal prosthesis and product thereof
Assignee: United States Department of Energy
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Filing: 1973-06-05
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Granted: 1978-01-24
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Expires: 1993-06-05
Abstract
Abstract A method for producing porous graphite for use as bone replacement with a structure for osteon penetration. Graphite is produced with ordered circular pores of 100 to 1000 microns in diameter covering at least 25% of the exposed surfaces. A cylindrical fiber is coated with a carbon flour-pitch mix and is then wound on a bobbin in a predetermined manner. The product of winding is dried, pressed, carbonized, and then graphitized. The fibers are removed either chemically or by volatilization during carbonization or graphitization.
Inventors
- 👤 Walter P. Eatherly
- 👤 J. M. Robbins
- 👤 David E. Rosson, Sr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:46
CPC Classifications
C; C04; C04B; C04B38/00; C04B38/06; C04B38/063; A; A61; A61F; A61F2/00; A61F2/02; A61F2/28; A61L; A61L27/00; A61L27/02; A61L27/08; B; B01; B01J; B01J37/00; B01J37/0009; B01J37/0018; C01; C01B; C01B32/00; C01B32/30; C01B32/354; C01B32/384; C04B35/00; C04B35/515; C04B35/52; C04B35/528; C04B35/532; C04B38/04; A61F2/30; A61F2002/30001; A61F2002/30108; A61F2002/30199; A61F2002/30224; A61F2002/30225; A61F2/30767; A61F2/30771; A61F2002/30772; A61F2002/30784; A61F2002/30785; A61F2230/00; A61F2230/0063; A61F2230/0069; A61F2310/00; A61F2310/00005; A61F2310/00161; A61F2310/00173; C04B2111/00; C04B2111/00474; C04B2111/00836; Y; Y10; Y10S; Y10S623/00; Y10S623/92; Y10S623/923; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1003; Y10T428/00; Y10T428/21; Y10T428/24; Y10T428/24273; Y10T428/30
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
164 words
A method for producing a prosthetic article, comprising the steps of: passing a fugitive fiber through a slurry comprising a carbon powder filler and a thermosetting carbon precursor binder to coat said fiber with said slurry; winding said fiber into a generally elliptical toroidal configuration having cross sections containing a parallel array of fibers created by the arrangement of said fugitive fiber, said parallel array of fibers having interstices between said fibers substantially filled with said slurry; setting said binder to create a cured configuration; cutting said cured configuration at points substantially perpendicular to said parallel array to produce a plurality of generally cylindrical sections having said parallel array of fibers embodied therein with said fibers being substantially parallel to the axis of each said cylindrical section; destructively removing said parallel array of fibers from said cylindrical sections to leave uniformly dispersed generally parallel pores having a diameter within the range of 100 to 1000 micrometers within carbon precursor relics; and carbonizing said relics.
Claim 2
Independent Claim
164 words
A method for producing a prosthetic article, comprising the steps of: passing a fugitive fiber through a slurry comprising a carbon powder filler and a thermosetting carbon precursor binder to coat said fiber with said slurry; winding said fiber into a generally elliptical toroidal configuration having cross sections containing a parallel array of fibers created by the arrangement of said fugitive fiber, said parallel array of fibers having interstices between said fibers substantially filled with said slurry; setting said binder to create a cured configuration; cutting said cured configuration at points substantially perpendicular to said parallel array to produce a plurality of generally cylindrical sections having said parallel array of fibers embodied therein with said fibers being substantially parallel to the axis of each said cylindrical section; destructively removing said parallel array of fibers from said cylindrical sections to leave uniformly dispersed generally parallel pores having a diameter within the range of 100 to 1000 micrometers within carbon precursor relics; and carbonizing said relics.
Claim 3
Dependent Claim
11 words
The method according to claim 1 further including graphitizing said relic.
Claim 4
Dependent Claim
17 words
The method according to claim 1 wherein said step of removing comprises volatilizing said fiber by heating.
Claim 5
Dependent Claim
15 words
The method according to claim 1 wherein said step of removing comprises etching said fiber.
Claim 6
Dependent Claim
21 words
The method according to claim 1 wherein said fiber is selected from the group consisting of nylon, copper, tin, and iron.
Claim 7
Dependent Claim
45 words
The method according to claim 1 wherein said carbon powder comprises raw air-blown coke, calcined air-blown coke, and carbon black, said binder is selected from the group consisting of pre-polymerized furfuryl alcohol and coal tar pitch and said slurry further comprises acetone as a solvent.
Claim 8
Dependent Claim
9 words
The product produced by the process of claim 1.
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) | 1981-01-23 | 1981-07-25 | 1982-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-23 | 1985-07-25 | 1986-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-23 | 1989-07-25 | 1990-01-24 | $7700.00 | Window Closed / Lapsed |