Patent EP0625490B1 successfully refreshed from Google Patents.
EP0625490B1
Expired / Lapsed
EP
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Method for the preparation of carbonated hydroxyapatite compositions
Assignee: Abonetics Ltd
•
Filing: 1994-05-16
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Granted: 1996-06-19
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Expires: 2014-05-16
Abstract
No abstract record available.
Inventors
- 👤 William Prof. Bonfield
- 👤 Serena Michelle Best
- 👤 Jake Edward Barralet
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 22:37
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/02; A61L27/12; C; C04; C04B; C04B35/00; C04B35/01; C04B35/447; A61F; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
120 words
A method for the preparation of a carbonated hydroxyapatite composition which has a density of at least 95% of the theoretical density, which method comprises sintering at substantially atmosphere pressure a green carbonated hydroxyapatite composition containing up to 20% by weight of C0₃²⁻ ions and having a green density of from 25 to 60% of the theoretical density at a temperature in the range of from 750° to 1450°C in carbon dioxide containing from 0.001 to 0.10 grams of water per litre of gas, the sintering temperature being selected within the above range and the green composition being sintered for a period of time sufficient to cause the green composition to densify to at least 95% of the theoretical density.
Claim 2
Dependent Claim
22 words
A method as claimed in claim 1 wherein the green composition has a density of 30 to 40% of the theoretical density.
Claim 3
Dependent Claim
23 words
A method as claimed in claim 1 or claim 2 wherein the sintering temperature is in the range of from 750° to 1150°C.
Claim 4
Independent Claim
27 words
A method as claimed in any one of the preceding claims wherein the carbon dioxide contains from 0.01 to 0.02 grams of water per litre of gas.
Claim 5
Independent Claim
27 words
A method as claimed in any one of the preceding claims wherein the sintering is carried out for a period of time of up to 24 hours.
Claim 6
Dependent Claim
23 words
A method as claimed in claim 5 wherein the sintering is carried out for a period of time of up to 4 hours.
Claim 7
Independent Claim
28 words
A method as claimed in any one of the preceding claims wherein the green carbonated hydroxyapatite composition has a carbonate content of from 3 to 10% by weight.
Claim 8
Independent Claim
26 words
A method as claimed in any one of the preceding claims wherein the carbonated hydroxyapatite composition comprises from 4 to 6% by weight of C0₃²⁻ ions.
Claim 9
Independent Claim
27 words
A method as claimed in any one of the preceding claims wherein the carbonated hydroxyapatite has a density of from 98% to 100% of the theoretical density.
Claim 10
Dependent Claim
13 words
A method as claimed in claim 9 wherein the carbonated hydroxyapatite is translucent.
Claim 11
Independent Claim
91 words
A method for the preparation of a carbonated hydroxyapatite composition which has a density of at least 95% of the theoretical density, which method comprises sintering at substantially atmosphere pressure a green carbonated hydroxyapatite composition containing up to 20% by weight of C0₃²⁻ ions at a temperature in the range of from 1000° to 1450°C in carbon dioxide containing from 0.001 to 0.10 grams of water per litre of gas, for a period of time sufficient to cause the green compact to densify to at least 95% of the theoretical density.
Claim 12
Dependent Claim
20 words
A method as claimed in claim 11 wherein the sintering temperature is in the range of from 1100° to 1300°C.
Claim 13
Dependent Claim
26 words
A method as claimed in claim 11 or claim 12 wherein the carbon dioxide contains from 0.01 to 0.02 grams of water per litre of gas.
Claim 14
Dependent Claim
22 words
A method as claimed in claim 11 wherein the carbonated hydroxyapatite composition comprises from 4 to 6% by weight of C0₃²⁻ ions.
References Cited (Backward Citations)
No citation records indexed.
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