US4632842A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Glow discharge process for producing implantable devices
Assignee: Atrium Medical Corp
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Filing: 1985-06-20
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Granted: 1986-12-30
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Expires: 2005-06-20
Abstract
Abstract Disclosed is a method of producing implantable prosthetic devices, e.g., tubular vascular prostheses having a substantially non-thrombogenic inside surface and a biocompatible outside surface. The method involves deposition onto an elongate substrate, e.g., a porous tubular substrate, of a fluorine-containing coating by inducing glow discharge progressively along the length of a tubular reaction vessel. A polymerizable fluorine-containing gas is flowed through the tubular substrate and a portion of the gas migrates radially to traverse the pores of the substrate. An RF field is applied to successive volumes of the gas within the vessel and tube. A substantially non-thrombogenic fluorinated coating with a first fluorine to carbon ratio deposits and bonds to the inside surface of the substrate, and a fluorinated biocompatible cross-linked coating with a lower F/C atomic ratio than the inside coating deposits and bonds to the outside surface of the substrate. The method of the invention can produce uniform coatings containing fluorine over the surface of elongated substrates. The coatings can be engineered to have a very low surface energy and to be essentially non-thrombogenic.
Inventors
- 👤 Theodore Karwoski
- 👤 Yasuo Matsuzawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:41
CPC Classifications
A; A61; A61L; A61L33/00; A61L33/0076; A61L33/0088; A61F; A61F2/00; A61F2/02; A61F2/04; A61F2/06; C; C08; C08F; C08F8/00; C08F8/18; C08F8/20; C08F8/22; C08J; C08J7/00; C08J7/12; C08J7/126
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
190 words
A method of producing a tubular vascular prosthesis having a substantially non-thrombogenic inside surface and a biocompatible outside surface, said method comprising the steps of: A. placing an elongate organic tubular substrate defining pores and having a selected outside diameter within a tubular reaction vessel; B. establishing a flow of a fluorine-containing gas through said tubular substrate at a subatmospheric pressure; C. permitting a portion of said gas to diffuse through said pores in transit through said tube; D. applying an RF field to a portion of the volume of gas within said reaction vessel to produce glow discharge; and E. inducing relative motion of said RF field and said tubular substrate to deposit along the length of said substrate a substantially non-thrombogenic, polymerized, cross-linked coating bonded to the inside surface of said substrate having a first F/C atomic ratio and a biocompatible, polymerized, cross-linked coating bonded to the outside surface of said substrate having an F/C atomic ratio lower than said first ratio wherein deposition of said polymerizable coating is controlled by controlling the pressure and flow rates of said gas and the field strength of said RF field.
Claim 2
Independent Claim
190 words
A method of producing a tubular vascular prosthesis having a substantially non-thrombogenic inside surface and a biocompatible outside surface, said method comprising the steps of: A. placing an elongate organic tubular substrate defining pores and having a selected outside diameter within a tubular reaction vessel; B. establishing a flow of a fluorine-containing gas through said tubular substrate at a subatmospheric pressure; C. permitting a portion of said gas to diffuse through said pores in transit through said tube; D. applying an RF field to a portion of the volume of gas within said reaction vessel to produce glow discharge; and E. inducing relative motion of said RF field and said tubular substrate to deposit along the length of said substrate a substantially non-thrombogenic, polymerized, cross-linked coating bonded to the inside surface of said substrate having a first F/C atomic ratio and a biocompatible, polymerized, cross-linked coating bonded to the outside surface of said substrate having an F/C atomic ratio lower than said first ratio wherein deposition of said polymerizable coating is controlled by controlling the pressure and flow rates of said gas and the field strength of said RF field.
Claim 3
Dependent Claim
64 words
The method of claim 1 wherein the flow established in step B is controlled to maintain a substantially constant density of available reactive species of said fluorine-containing polymerizable gas at inside surfaces of said substrate and within said RF field during relative motion to produce a cross-linked coating having a substantially uniform F/C ratio along the length of the inside surface of said substrate.
Claim 4
Dependent Claim
26 words
The method of claim 1 wherein the tubular reaction vessel has an inside diameter less than one mm than the outside diameter of said tubular substrate.
Claim 5
Dependent Claim
19 words
The method of claim 1 wherein said fluorine containing gas is substantially free of oxygen and oxygen containing compounds.
Claim 6
Dependent Claim
17 words
The method of claim 1 wherein the RF field is moved along the length of said substrate.
Claim 7
Dependent Claim
22 words
The method of claim 1 wherein the gas comprises a gas having a fluorine to carbon atomic ratio of at least 2.0.
Claim 8
Dependent Claim
10 words
The method of claim 6 wherein said gas comprises tetrafluoroethylene.
Claim 9
Dependent Claim
32 words
The method of claim 1 wherein the deposition of polymerized coating is controlled to produce a coating having an F/C ratio greater than 1.5 bonded to the inside surface of said substrate.
Claim 10
Dependent Claim
12 words
The method of claim 1 wherein said substrate comprises a fabric tube.
Claim 11
Dependent Claim
21 words
The method of claim 9 wherein said fabric tube comprising threads composed of fibers less than approximately 15 microns in diameter.
Claim 12
Dependent Claim
18 words
The method of claim 9 wherein said fabric tube has a wall thickness less than about 0.60 mm.
Claim 13
Dependent Claim
12 words
The method of claim 9 wherein said fabric is a knitted fabric.
Claim 14
Dependent Claim
12 words
The method of claim 9 wherein said fabric is a woven fabric.
Claim 15
Dependent Claim
12 words
The method of claim 9 wherein said fabric is a non-woven fabric.
Claim 16
Dependent Claim
11 words
The method of claim 1 wherein said substrate comprises polyethylene terephthalate.
Claim 17
Dependent Claim
47 words
The method of claim 9 wherein said fabric tube comprises circumferentially oriented fill threads and longitudinally oriented warp threads defining loops extending radially from between said fill threads, said loops being set to return to a loop configuration upon the release of axial stress on said tube.
Claim 18
Dependent Claim
11 words
The method of claim 1 wherein said tubular substrate is elastic.
Claim 19
Independent Claim
147 words
A method of coating an elongate organic substrate to produce a uniform non-thrombogenic surface thereon having an F/C ratio greater than 1.5, said method comprising the steps of: A. placing said elongate organic substrate within a tubular reaction vessel; B. establishing a flow of a fluorine containing gas having an F/C atomic ratio of at least two through said vessel and about said substrate at a subatmospheric pressure; C. applying an RF field to a portion of the volume of gas within said vessel to produce glow discharge; D. inducing relative motion of said RF field and said elongate substrate while controlling the density of available reactive species from said gas in the volume of said glow discharge adjacent a surface of said substrate to deposit along the length of said substrate a substantially uniform, non-thrombogenic, polymerized, cross-linked, fluorine-containing coating having an F/C ratio greater than 1.5.
Claim 20
Independent Claim
147 words
A method of coating an elongate organic substrate to produce a uniform non-thrombogenic surface thereon having an F/C ratio greater than 1.5, said method comprising the steps of: A. placing said elongate organic substrate within a tubular reaction vessel; B. establishing a flow of a fluorine containing gas having an F/C atomic ratio of at least two through said vessel and about said substrate at a subatmospheric pressure; C. applying an RF field to a portion of the volume of gas within said vessel to produce glow discharge; D. inducing relative motion of said RF field and said elongate substrate while controlling the density of available reactive species from said gas in the volume of said glow discharge adjacent a surface of said substrate to deposit along the length of said substrate a substantially uniform, non-thrombogenic, polymerized, cross-linked, fluorine-containing coating having an F/C ratio greater than 1.5.
Claim 21
Dependent Claim
17 words
The method of claim 18 wherein the RF field is moved along the length of said substrate.
Claim 22
Dependent Claim
11 words
The method of claim 18 wherein said fluorine-containing gas is tetrafluoroethylene.
Claim 23
Dependent Claim
17 words
The method of claim 18 wherein said gas is substantially free of oxygen or oxygen containing compounds.
Claim 24
Dependent Claim
12 words
The method of claim 18 wherein said elongate substrate comprises polyethylene terephthalate.
Claim 25
Dependent Claim
11 words
The method of claim 18 wherein said substrate comprises a fabric.
Claim 26
Dependent Claim
43 words
The method of claim 19 wherein the density of available reactive species is controlled to be substantially constant at the surface of said substrate in the area of glow discharge by varying gas pressure at a gas inlet end of said tubular vessel.
Claim 27
Dependent Claim
48 words
The method of claim 19 wherein the density of available reactive species is controlled to be substantially constant at the surface of said substrate in the area of glow discharge by varying gas pressure at a gas inlet end and a gas outlet end of said tubular vessel.
References Cited (Backward Citations)
US3068510A
Cited
US3663265A
Cited
US3839743A
Cited
US4076916A
Cited
US4193138A
Cited
US4252848A
Cited
US4229838A
Cited
JPS5456672A
Cited
US4188426A
Cited
US4286341A
Cited
US4264750A
Cited
US4349582A
Cited
US4404256A
Cited
US4488954A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-29 | 1990-06-30 | 1990-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-29 | 1994-06-30 | 1994-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-29 | 1998-06-30 | 1998-12-30 | $7700.00 | Window Closed / Lapsed |