Patent US5150110A successfully refreshed from Google Patents.
Patent EP0737481A1 successfully refreshed from Google Patents.
EP0737481A1
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EP
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Method for improving wear resistance of polymeric bio-implantable components
Assignee: DePuy Products Inc
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Filing: 1996-04-02
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Granted: —
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Expires: 2016-04-02
Abstract
Abstract Wear resistance and oxidation resistance of bioimplantable polymeric parts is improved by packaging the parts within flexible, gas impermeable containers while subjecting the containers and the parts to a relatively high vacuum force. The containers are heat sealed while subjected to the vacuum force such that, upon sealing, hydrostatic pressure is exerted on the part. Following sealing of the packages, the packages and their contents are irradiated to an extent sufficient to sterilize the parts and to promote crosslinking within the part. Alternatively, the same property enhancements can be imparted to polymeric parts by packaging the part within rigid or flexible containers, minimizing the oxygen content within the containers, pressurizing the containers with an inert gas, or with a mixture of hydrogen and an inert gas, to greater than 1.5 atmospheres, and irradiating the part and the container.
Inventors
- 👤 John V. Hamilton
- 👤 Mark A. Manasas
- 👤 Timothy M. Flynn
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 03:09
CPC Classifications
A; A61; A61L; A61L2/00; A61L2/02; A61L2/08; A61L2/081; A61L2/082; A61L2/087; A61L27/00; A61L27/14; A61L27/16; B; B65; B65B; B65B55/00; B65B55/02; B65B55/04; B65B55/08; B65B55/12; B65B55/16; C; C08; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/06; A61L2103/00; A61L2103/15; B65B31/00; B65B31/04; C08L2207/00; C08L2207/06; C08L2207/068
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
126 words
A method for improving the wear resistance of a polymeric manufactured part, comprising the steps of: providing one or more manufactured polymeric parts; placing the parts in one or more gas impermeable, flexible packaging containers wherein each container has at least one heat sealable opening therein; subjecting the packaging container and the polymeric parts to a vacuum force; heat sealing the flexible packaging container while subjected to the vacuum force such that upon sealing of the packaging container hydrostatic pressure is exerted on the part; and irradiating the heat sealed packages and the parts for a period of time sufficient to sterilize the parts and to promote crosslinking within the polymer that forms the part; the part being characterized by improved resistance to wear and oxidation.
Claim 2
Dependent Claim
33 words
The method of claim 1 wherein the vacuum force is sufficient to remove all or substantially all of the oxygen from within the packaging container and the environment adjacent to the packaging container.
Claim 3
Dependent Claim
20 words
The method of claim 1 or claim 2 wherein the vacuum force is in the range of about 500-1013 mbar.
Claim 4
Independent Claim
28 words
The method of any one of claims 1 to 3 wherein the hydrostatic pressure exerted on the part is in the range of about 7 to 14.7 psi.
Claim 5
Independent Claim
29 words
The method of any one of claims 1 to 4 wherein any gas contained within the flexible packaging container is characterized by a reduced number of mole of hydrogen.
Claim 6
Dependent Claim
24 words
The method of claim 5 wherein the gas within the flexible packaging container has less than about 2.2 x 10 -5 moles/g of hydrogen.
Claim 7
Independent Claim
39 words
The method of any one of claims 1 to 6 wherein, following the step of irradiating, the part is characterised by a gel content in the range of 75 to 100% as determined by Method C of ASTM D2765-90.
Claim 8
Independent Claim
33 words
The method of any one of claims 1 to 7 wherein the flexible packaging container is manufactured of a metal foil that is surrounded by one or more layers of a polymer film.
Claim 9
Independent Claim
54 words
The method of any one of claims 1 to 8 wherein the polymeric part is made from low density polyethylene, high density polyethylene, ultrahigh molecular weight polyethylene, polypropylene, polyester, nylon, polyurethane, or poly(methylmethacrylate) and is preferably made of an ultrahigh molecular weight polyethylene having a number average molecular weight greater than about 1.0 million.
Claim 10
Independent Claim
26 words
The method of any one of claims 1 to 9 wherein the polymeric part is manufactured by compression moulding process or by a RAM extrusion process.
Claim 11
Independent Claim
54 words
The method of any one of claims 1 to 10 wherein, following the step of irradiating, the method further comprises the step of aging the polymeric parts within a hydrogen enriched atmosphere of the packaging container for a period of time sufficient to enable hydrogen atoms to recombine with free radicals within the polymer.
Claim 12
Independent Claim
21 words
The method of claims 11 wherein the hydrogen rich atmosphere within the container has approximately 30% to 100% hydrogen by volume.
Claim 13
Independent Claim
105 words
A method for improving the wear resistance of a polymeric manufactured part, comprising the steps of: providing one or more manufactured polymeric parts; placing the parts in one or more sealable, gas impermeable packaging containers; removing all or substantially all of the oxygen from within the packaging container, pressurizing the packaging containers with an inert gas at a pressure greater than 1.5 to 4.0 atmospheres; irradiating the pressurized containers and the polymeric parts for a period of time sufficient to sterilize the parts and to promote crosslinking within the polymer that forms the part, the part being characterized by improved resistance to wear and oxidation.
Claim 14
Independent Claim
139 words
A method for improving the wear resistance of a polymeric manufactured part, comprising the steps of: providing one or more manufactured polymeric parts; placing the parts in one or more sealable, gas impermeable packaging containers. removing all or substantially all of the oxygen from within the packaging container, pressurizing the packaging containers with a mixture of hydrogen gas and an inert gas at a pressure greater than about 1.5 atmospheres; irradiating the pressurized containers and the polymeric parts for a period of time sufficient to sterilize the parts and to promote crosslinking within the polymer that forms the part; and aging the part within the atmosphere of the irradiated packaging container for a period of time sufficient for hydrogen atoms to recombine with free radicals within the part; the part being characterized by improved resistance to wear and oxidation.
Claim 15
Dependent Claim
55 words
The method of claim 16 wherein the mixture of hydrogen gas and inert gas is characterized by a minimum of about 2.2 x 10 -3 moles of hydrogen gas per gram of polymeric material within the packaging container and a volumetric concentration of hydrogen within the container in the range of about 30% to 95%.
Claim 16
Independent Claim
27 words
The method of any one of claims 11, 12, 14 and 15 wherein the part is aged within the packaging container for at least about 48 hours.
Claim 17
Independent Claim
32 words
The method of any one of claims 13 to 16 wherein the step of minimizing the oxygen concentration within the packaging container is effected by flushing the container with an inert gas.
Claim 18
Independent Claim
32 words
The method of any one of claims 13 to 16 wherein the step of minimizing the oxygen concentration within the packaging container is effected by applying a vacuum force to the container.
Claim 19
Independent Claim
19 words
The method of any one of claims 13 to 18 wherein the inert gas is argon, helium, or nitrogen.
Claim 20
Independent Claim
16 words
The method of any one of claims 13 to 19 wherein the packaging container is rigid.
Claim 21
Independent Claim
16 words
The method of any one of claims 13 to 19 wherein the packaging container is flexible.
Claim 22
Independent Claim
25 words
The method of any one of claims 1 to 21 wherein the step of irradiating is carried out using gamma, x-ray, or electron beam radiation.
Claim 23
Dependent Claim
23 words
The method of claim 22 wherein the step of irradiating is carried out until a dose of about 20-60 KGy has been achieved.
References Cited (Backward Citations)
FR2025430A1
Cited
FR2085832A1
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US5014494A
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US5133757A
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EP0603789A2
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WO1994027651A1
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