US4055862A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Human body implant of graphitic carbon fiber reinforced ultra-high molecular weight polyethylene
Assignee: Zimmer USA Inc
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Filing: 1976-01-23
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Granted: 1977-11-01
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Expires: 1996-01-23
Abstract
Abstract A medical body implant element that is intended to experience rolling or sliding pressure during its function in the human body comprises microparticles of ultra-high molecular weight polyethylene which are fused together into a matrix. A quantity of graphitic carbon fibers of short, random lengths is disposed in intersticies of the matrix. The resultant composite is wear-resistant and substantially isotropic.
Inventors
- 👤 Gene M. Farling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:10
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/30; A61F2/38; A61L; A61L27/00; A61L27/40; A61L27/44; A61L27/443; A61F2002/3895
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
75 words
A medical implant element which is to be subjected to rolling or sliding pressure or a combination of such pressures in the human body, comprising: a plurality of microparticles of ultra-high molecular weight polyethylene resin fused together into a matrix; and a quantity of graphitic carbon, consisting essentially of a substantially unoriented array of short, random length fibers, disposed in interstices of said matrix, said graphitic carbon fiber-containing matrix being a wear-resistant, substantially isotropic member.
Claim 2
Dependent Claim
75 words
A medical implant element which is to be subjected to rolling or sliding pressure or a combination of such pressures in the human body, comprising: a plurality of microparticles of ultra-high molecular weight polyethylene resin fused together into a matrix; and a quantity of graphitic carbon, consisting essentially of a substantially unoriented array of short, random length fibers, disposed in interstices of said matrix, said graphitic carbon fiber-containing matrix being a wear-resistant, substantially isotropic member.
Claim 3
Dependent Claim
23 words
A medical implant element according to claim 1 wherein said fibers have a length of from about 100 microns to about 3 millimeters.
Claim 4
Dependent Claim
22 words
A medical implant element according to claim 1 wherein said fibers have a diameter of from about 5 to about 15 microns.
Claim 5
Dependent Claim
23 words
A medical implant element according to claim 1 which further comprises an X-ray opaque member embedded therein spaced inwardly from the surface thereof.
Claim 6
Dependent Claim
21 words
A medical implant element according to claim 1 wherein the polyethylene molecules in said matrix are disposed in substantially random orientation.
Claim 7
Dependent Claim
29 words
A medical implant element according to claim 1 wherein said graphitic carbon is present in an amount of up to about 30 per cent by weight of said implant.
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) | 1980-10-31 | 1981-05-02 | 1981-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-31 | 1985-05-02 | 1985-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-31 | 1989-05-02 | 1989-11-01 | $7700.00 | Window Closed / Lapsed |