US5958504A
Expired / Lapsed
US
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Hydroxyapatite coatings and a method of their manufacture
Assignee: Etex Corp
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Filing: 1996-12-18
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Granted: 1999-09-28
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Expires: 2016-12-18
Abstract
Abstract A process for the production of a hydroxyapatite coated article includes contacting a coating comprising hydroxyapatite with a recrystallization medium, pressurizing the recrystallization medium, heating the coated article under conditions of reduced oxygen activity at a temperature in the range of 100 to 350° C. A process for the production of highly crystalline hydroxyapatite coated articles includes contacting a coating comprising hydroxyapatite with recrystallization medium containing hydroxyapatite particles, pressurizing the recrystallization medium, and heating the immersed coated article under conditions effective to crystallize hydroxyapatite.
Inventors
- 👤 Dusuk Duke Lee
- 👤 William T. Conner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:35
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/28; A61L27/30; A61L27/32; A61F; A61F2310/00; A61F2310/00389; A61F2310/00592; A61F2310/00796
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
94 words
A process for the production of a hydroxyapatite coated article, comprising the steps of: contacting an article, said article having a hydroxyapatite coating, with a recrystallization medium comprised of a liquid; pressurizing said recrystallization medium; and hydrothermally treating the coated article to effect crystallization of said hydroxyapatite coating under conditions of reduced oxygen activity, said reduced oxygen activity being obtained by reducing the oven content of the recapitalization medium or an atmosphere in contact with the recrystallization medium to less than the oxygen content of an aqueous recrystallization medium in equilibrium with atmospheric air.
Claim 2
Dependent Claim
94 words
A process for the production of a hydroxyapatite coated article, comprising the steps of: contacting an article, said article having a hydroxyapatite coating, with a recrystallization medium comprised of a liquid; pressurizing said recrystallization medium; and hydrothermally treating the coated article to effect crystallization of said hydroxyapatite coating under conditions of reduced oxygen activity, said reduced oxygen activity being obtained by reducing the oven content of the recapitalization medium or an atmosphere in contact with the recrystallization medium to less than the oxygen content of an aqueous recrystallization medium in equilibrium with atmospheric air.
Claim 3
Dependent Claim
13 words
The method of claim 1, wherein the recrystallization medium further comprises hydroxyapatite particles.
Claim 4
Dependent Claim
50 words
A process for the production of a hydroxyapatite coated article, comprising the steps of: contacting an article, said article having a hydroxyapatite coating, with a recrystallization medium comprised of hydroxyapatite particles and a liquid; pressurizing said recrystallization medium; and hydrothermally treating the coated article to obtain a crystalline hydroxyapatite coating.
Claim 5
Dependent Claim
50 words
A process for the production of a hydroxyapatite coated article, comprising the steps of: contacting an article, said article having a hydroxyapatite coating, with a recrystallization medium comprised of hydroxyapatite particles and a liquid; pressurizing said recrystallization medium; and hydrothermally treating the coated article to obtain a crystalline hydroxyapatite coating.
Claim 6
Dependent Claim
56 words
A process for the production of a hydroxyapatite coated article, comprising the steps of: contacting an article, said article having a hydroxyapatite coating, with a recrystallization medium comprised of hydroxyapatite particles and a mixture of an organic liquid and water; pressurizing said recrystallization medium; and hydrothermally treating the coated article to obtain a crystalline hydroxyapatite coating.
Claim 7
Dependent Claim
56 words
A process for the production of a hydroxyapatite coated article, comprising the steps of: contacting an article, said article having a hydroxyapatite coating, with a recrystallization medium comprised of hydroxyapatite particles and a mixture of an organic liquid and water; pressurizing said recrystallization medium; and hydrothermally treating the coated article to obtain a crystalline hydroxyapatite coating.
Claim 8
Dependent Claim
17 words
The method of claim 1, 2, 3 or 4, wherein the step of pressurizing comprises externally pressurizing.
Claim 9
Dependent Claim
17 words
The method of claim 1, 2, 3 or 4 wherein the step of pressurizing comprises internally pressurizing.
Claim 10
Dependent Claim
29 words
The method of claim 6, wherein the step of internally pressurizing comprises the steps of: disposing the recrystallization medium in a vessel; sealing the vessel; and heating the vessel.
Claim 11
Dependent Claim
30 words
The method of claim 1, 2, 3 or 4, wherein the step of contacting the coated article with the recrystallization medium comprises immersing the coated article in the recrystallization medium.
Claim 12
Dependent Claim
28 words
The method of claim 1, 2, 3 or 4, wherein the step of heating comprises heating at a temperature in the range of about 100 to 350° C.
Claim 13
Dependent Claim
27 words
The method of claim 1, 2 or 4, wherein the step of heating comprises heating at a temperature in the range of about 200 to 300° C.
Claim 14
Dependent Claim
24 words
The method of claim 3, wherein the step of heating comprises heating at a temperature in the range of about 120 to 140° C.
Claim 15
Dependent Claim
28 words
The method of claim 1, 2, 3 or 4, wherein the step of heating comprises heating at a pressure in the range of about 0.1 and 15 MPa.
Claim 16
Dependent Claim
37 words
The method of claim 1, 3 or 4, wherein the step of immersing the coated article in a recrystallization medium comprises immersing the coated article in a recrystallization medium comprising about 0.01 to 10 wt % hydroxyapatite.
Claim 17
Dependent Claim
35 words
The method of claim 1, 3 or 4, wherein the step of immersing the coated article in a recrystallization medium comprises immersing the coated article in a recrystallization medium comprising about 0.5 wt % hydroxyapatite.
Claim 18
Dependent Claim
48 words
The method of claim 1, 3 or 4, wherein the step of contacting the coated article with a recrystallization medium comprising hydroxyapatite particles comprises contacting the coated article with a recrystallization medium comprising hydroxyapatite particles having a particle size in the range of about 1 to 200 microns.
Claim 19
Dependent Claim
45 words
The method of claim 1, 2 or 3, wherein the step of contacting the coated article with a recrystallization medium comprising a liquid comprises contacting the coated article with a liquid selected from the group consisting of water, aqueous solutions, organic liquids and mixtures thereof.
Claim 20
Dependent Claim
28 words
The method of claim 1 or 2, wherein the step of heating under conditions of reduced oxygen activity comprises heating in a recrystallization medium comprising an oxygen scavenger.
Claim 21
Dependent Claim
23 words
The method of claim 17, wherein said oxygen scavenger is selected from the group consisting of alkanes, alcohols, organic esters and mixtures thereof.
Claim 22
Dependent Claim
53 words
The method of claim 1 or 2, wherein the step of heating under conditions of reduced oxygen activity comprises the steps of: providing a vessel for containing the recrystallization medium; introducing an oxygen diluting atmosphere above the recrystallization medium in the vessel; and heating the vessel at a temperature sufficient to crystallize hydroxyapatite.
Claim 23
Dependent Claim
62 words
The method of claim 1 or 2, wherein the step of heating under conditions of reduced oxygen activity comprises the steps of: providing a vessel for containing the recrystallization medium; evacuating the vessel containing the recrystallization medium and coated article; introducing an oxygen diluting atmosphere into the evacuated vessel; and heating the vessel at a temperature sufficient to effect crystallization of hydroxyapatite.
Claim 24
Dependent Claim
24 words
The method of claim 19, wherein the oxygen diluting atmosphere is selected from the group consisting of inert gas, argon and deoxygenated water vapor.
Claim 25
Dependent Claim
24 words
The method of claim 20, wherein the oxygen diluting atmosphere is selected from the group consisting of inert gas, argon and deoxygenated water vapor.
Claim 26
Dependent Claim
62 words
The method of claim 1 or 2, wherein the step of heating under conditions of reduced oxygen activity comprises the steps of: providing a vessel for containing the recrystallization medium; evacuating the vessel containing the recrystallization medium and coated article; sealing the vessel, such that a deoxygenated atmosphere results; and heating the vessel at a temperature sufficient to effect crystallization of hydroxyapatite.
Claim 27
Dependent Claim
62 words
The method of claim 1 or 2, wherein the step of heating under reduced oxygen activity comprises the steps of: providing a vessel for containing the recrystallization medium; boiling the recrystallization medium containing the coated article; sealing the reaction vessel, such that a deoxygenated atmosphere is formed above the recrystallization medium; and heating at a temperature sufficient to effect crystallization of hydroxyapatite.
Claim 28
Dependent Claim
31 words
The method of claim 1 or 2, wherein the step of heating under reduced oxygen activity comprises heating at a temperature in the range of about 120° C. to 140° C.
Claim 29
Dependent Claim
22 words
The method of claim 4, wherein the organic liquid selected from the group consisting of alcohol, alkanes, organic esters and mixtures thereof.
Claim 30
Dependent Claim
24 words
The method of claim 4, wherein the step of contacting the coated article with an organic liquid comprises contacted the coated article, with ethanol.
Claim 31
Dependent Claim
19 words
The method of claim 4, wherein the recrystallization medium comprises water in the range of 1 to 20% vol.
Claim 32
Dependent Claim
48 words
The method of claim 4, wherein the step of contacting the coated article with an organic liquid comprises contacting the coated article with a 90:10 ethanol:water mixture; and wherein the step of heating comprises heating at a temperature in the range of about 200° C. to 300° C.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2002-09-27 | 2003-03-29 | 2003-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-09-27 | 2007-03-29 | 2007-09-28 | $3760.00 | Window Closed / Lapsed |
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