US5133845A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making prosthesis of polymeric material coated with biocompatible carbon
Assignee: Sorin Biomedica Cardio SpA
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Filing: 1990-02-14
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Granted: 1992-07-28
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Expires: 2010-02-14
Abstract
Abstract A prosthetic device includes a turbostratic biocompatible carbon film firmly adherent to a substrate and having a density of at least 2.1 g/cm 3 . The carbon preferably is very thin, e.g., less than about one micron. The thin carbon biocompatible film covers at least that portion of the substrate which will be in contact with body tissue and/or fluids to insure against physiological rejection and degradation of the prosthetic device. The carbon can be deposited on a variety of substrates, including low temperature substrates, in situ, without adversely affecting the mechanical properties of the substrate. The prosthetic device of the invention is formed by triode sputtering vacuum deposition at a relatively low temperature to achieve the desired results with respect to the deposited carbon and the substrate and with respect to the required adherence therebetween.
Inventors
- 👤 Franco Vallana
- 👤 Pietro Arru
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:48
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/28; A61L27/30; A61L27/303; C; C23; C23C; C23C14/00; C23C14/06; C23C14/0605; C23C14/22; C23C14/34; C23C14/35; C23C14/354; C23C14/355; A61F; A61F2310/00; A61F2310/00389; A61F2310/00574
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
88 words
A method of forming a prosthetic device having a substrate, consisting essentially of: triode cathodic sputtering of carbon at a low temperature and a pressure of between 6×10 -4 to 6×10 -3 mbar and at a sputtering voltage of from about 2,000 to 3,200 volts and a sputtering current of from about 0.1 to 0.3 amps onto the substrate without degradation thereof to form a continuous turbostratic biocompatible carbon coating having a density of at least about 2.1 g/cm 3 on the substrate which is firmly adherent thereto.
Claim 2
Independent Claim
88 words
A method of forming a prosthetic device having a substrate, consisting essentially of: triode cathodic sputtering of carbon at a low temperature and a pressure of between 6×10 -4 to 6×10 -3 mbar and at a sputtering voltage of from about 2,000 to 3,200 volts and a sputtering current of from about 0.1 to 0.3 amps onto the substrate without degradation thereof to form a continuous turbostratic biocompatible carbon coating having a density of at least about 2.1 g/cm 3 on the substrate which is firmly adherent thereto.
Claim 3
Dependent Claim
25 words
The method of claim 1, wherein the step of triode cathodic sputtering is conducted at a filament current of rom about 80 to 90 amps.
Claim 4
Dependent Claim
25 words
The method of forming a prosthetic deevice according to claim 1, wherein the carbon cathode consists of graphite or pyrolytic carbon or a combination thereof.
Claim 5
Dependent Claim
26 words
The method of forming a prosthetic device according to claim 1, wherein the carbon cathode and anode are cooled by water conveyed through conduits continguous therewith.
Claim 6
Dependent Claim
29 words
The method according to claim 1, wherein the substrate is flat and is rotated about the carbon cathode and about itself for uniform distribution of the sputtered carbon thereon.
Claim 7
Dependent Claim
25 words
The method according to claim 1, wherein the substrate is tubular and is rotated about its axis for uniform distribution of the sputtered carbon thereon.
Claim 8
Dependent Claim
26 words
The method according to claim 1, wherein the substrate is suture yarn and is rotated about a frame for uniform distribution of the sputtered carbon thereon.
Claim 9
Dependent Claim
24 words
The method according to claim 1, further comprising masking portions of the substrate so that the sputtered carbon only is deposited on unmasked portions.
Claim 10
Dependent Claim
36 words
The method according to claim 1, wherein the substrate is a polyester resin and the temperature at the substrate is maintained at about 80° C. to enhance the adhesion of the sputtered carbon to the substrate.
Claim 11
Dependent Claim
23 words
The method according to claim 1, wherein the carbon sputtered onto the substrate has a thickness of not more than about 1.0 micron.
Claim 12
Independent Claim
43 words
The method according to cliam 1, wherein the material of the substrate is selected from the group consisting of polyester resins, polytetrafluoroethylene, silicone, polyacetal resins, polyurethanes, polyethylene, cobalt-chromium alloys, titanium and titanium alloys, and wherein the carbon sputtered on the substrate is turbostratic.
Claim 13
Independent Claim
43 words
The method according to cliam 1, wherein the material of the substrate is selected from the group consisting of polyester resins, polytetrafluoroethylene, silicone, polyacetal resins, polyurethanes, polyethylene, cobalt-chromium alloys, titanium and titanium alloys, and wherein the carbon sputtered on the substrate is turbostratic.
Claim 14
Dependent Claim
13 words
The method according to claim 1 wherein the substrate is a non-refractory metal.
Claim 15
Dependent Claim
16 words
The method according to claim 12 wherein the non-refractory metal is titanium or a titanium alloy.
Claim 16
Dependent Claim
13 words
The method of claim 12 wherein the non-refractory metal is a cobalt-chromium alloy.
Claim 17
Independent Claim
133 words
A method of forming a prosthetic device having a substrate, comprising: forming a plasma beam at a filament current of about 80-90 amps and directing the beam toward a carbon cathode circumscribed by an anode, the cathode and anode being remote from the site of formation of the plasma beam, sputtering the carbon cathode at a pressure of from about 6×10 -4 to 6×10 -3 mbar by said beam while cooling the cathode and anode and operating the cathode at from about 2,000 to 3,200 volts and a current of from about 0.1 to 0.3 amps, and directing said sputtered carbon onto the substrate without degradation thereof to form a biocompatible carbon coating on the substrate which is firmly adherent thereto, and has a density of at least about 2.1 g/cm 3 .
Claim 18
Independent Claim
133 words
A method of forming a prosthetic device having a substrate, comprising: forming a plasma beam at a filament current of about 80-90 amps and directing the beam toward a carbon cathode circumscribed by an anode, the cathode and anode being remote from the site of formation of the plasma beam, sputtering the carbon cathode at a pressure of from about 6×10 -4 to 6×10 -3 mbar by said beam while cooling the cathode and anode and operating the cathode at from about 2,000 to 3,200 volts and a current of from about 0.1 to 0.3 amps, and directing said sputtered carbon onto the substrate without degradation thereof to form a biocompatible carbon coating on the substrate which is firmly adherent thereto, and has a density of at least about 2.1 g/cm 3 .
Claim 19
Dependent Claim
19 words
The method of claim 15, wherein the density of the deposited carbon is at least 2.2 g/cm 3 .
Claim 20
Dependent Claim
21 words
The method of claim 16, wherein the density of the deposited carbon is from about 2.2 to 2.4 g/cm 3 .
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) | 1995-07-28 | 1996-01-27 | 1996-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-28 | 2000-01-27 | 2000-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-28 | 2004-01-27 | 2004-07-28 | $7700.00 | Window Closed / Lapsed |