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US5496399A Expired / Lapsed US ⏱️ 0.0 years remaining

Storage stable calcium phosphate cements

Assignee: KNC NOR Acquisition Sub Inc
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Filing: 1994-08-23
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Granted: 1996-03-05
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Expires: 2014-08-23
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Abstract

Abstract Two component, storage stable apatitic cement compositions, as well as methods for their production, are provided. The dry component of subject apatitic cements comprises basic calcium source particles at least partially coated with a partially neutralized acidic calcium phosphate. The dry component of subject compositions is prepared by combining basic calcium source particles with dissolved acidic phosphate in at least a partially aqueous medium, whereby the basic calcium source particles become partially coated with a partially neutralized acidic calcium phosphate. The reaction is terminated prior to completion of the reaction between the acidic phosphate and the basic calcium source by removing the available water from the reaction mixture. In a first mode, the subject cement may be produced by mechanically mixing an acidic phosphate source with basic calcium source particles in the presence of an aqueous solvent and stopping the reaction between the acid and base prior to completion. Alternatively, a phosphoric acid solution may be rapidly combined with a basic calcium phosphate particle slurry such that partially neutralized acidic calcium phosphate precipitates on the surface of the basic calcium phosphate particles.

Inventors

  • 👤 Ira C. Ison
  • 👤 Mark T. Fulmer
  • 👤 Bryan M. Barr
  • 👤 Brent R. Constantz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 19:46
CPC Classifications
C; C04; C04B; C04B20/00; C04B20/10; C04B20/1055; C04B20/107; A; A61; A61L; A61L27/00; A61L27/02; A61L27/12; C04B12/00; C04B12/02; C04B12/025; C04B20/1077; C04B28/00; C04B28/34; C04B28/344; C04B40/00; C04B40/06; A61F; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293; A61L2430/00; A61L2430/38; C04B2111/00; C04B2111/00474; C04B2111/00836; Y; Y10; Y10S; Y10S623/00; Y10S623/901; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294; Y10T428/2942; Y10T428/2949; Y10T428/2982; Y10T428/2991; Y10T428/2993

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 107 words
A method for producing a dry component for a storage stable, two component apatitic cement composition, said method comprising: mixing an acidic phosphate source with a basic calcium source in the presence of an aqueous solvent, whereby a reaction between said acidic phosphate source and basic calcium source occurs; and stopping the reaction between said acidic phosphate source and basic calcium source prior to completion by removing substantially all of the free water from said reaction mixture, resulting in solids substantially free of uncombined water; whereby a dry component comprising said basic calcium source at least partially coated with a partially neutralized acidic calcium phosphate is produced.
Claim 2
Independent Claim 107 words
A method for producing a dry component for a storage stable, two component apatitic cement composition, said method comprising: mixing an acidic phosphate source with a basic calcium source in the presence of an aqueous solvent, whereby a reaction between said acidic phosphate source and basic calcium source occurs; and stopping the reaction between said acidic phosphate source and basic calcium source prior to completion by removing substantially all of the free water from said reaction mixture, resulting in solids substantially free of uncombined water; whereby a dry component comprising said basic calcium source at least partially coated with a partially neutralized acidic calcium phosphate is produced.
Claim 3
Dependent Claim 16 words
The method according to claim 1, wherein said basic calcium source is a basic calcium phosphate.
Claim 4
Dependent Claim 25 words
The method according to claim 2, wherein said basic calcium phosphate is selected from the group consisting of tricalcium phosphate, tetracalcium phosphate and octacalcium phosphate.
Claim 5
Dependent Claim 37 words
The method according to claim 1, wherein said acidic phosphate source is selected from the group consisting of monobasic calcium phosphate monohydrate, monobasic calcium phosphate anhydrous, dibasic calcium phosphate anhydrous, dibasic calcium phosphate dihydrate and orthophosphoric acid.
Claim 6
Dependent Claim 19 words
The method according to claim 1, wherein 100% of said mixing occurs in the presence of said liquid phase.
Claim 7
Independent Claim 95 words
A method for producing a dry component for a storage stable two component apatitic cement composition, said method comprising: mixing an acidic phosphate source with tricalcium phosphate in the absence of a liquid phase, resulting in a dry mixture; mixing said dry mixture in the presence of an aqueous solvent; and stopping the reaction between said acidic phosphate source and tricalcium phosphate prior to completion by removing substantially all of the free water from said reaction mixture; whereby a dry component comprising tricalcium phosphate partially coated with a partially neutralized acidic calcium phosphate is produced.
Claim 8
Independent Claim 95 words
A method for producing a dry component for a storage stable two component apatitic cement composition, said method comprising: mixing an acidic phosphate source with tricalcium phosphate in the absence of a liquid phase, resulting in a dry mixture; mixing said dry mixture in the presence of an aqueous solvent; and stopping the reaction between said acidic phosphate source and tricalcium phosphate prior to completion by removing substantially all of the free water from said reaction mixture; whereby a dry component comprising tricalcium phosphate partially coated with a partially neutralized acidic calcium phosphate is produced.
Claim 9
Independent Claim 94 words
A method for producing a dry component for a storage stable two component apatitic cement composition, said method comprising: mixing a phosphoric acid source with tricalcium phosphate in the presence of an aqueous solvent, whereby a reaction between said phosphoric acid source and said tricalcium phosphate occurs; and stopping the reaction between said phosphoric acid source and tricalcium phosphate prior to completion by removing substantially all of the free water from said reaction mixture; whereby a dry component comprising tricalcium phosphate at least partially coated with a partially neutralized acidic calcium phosphate is produced.
Claim 10
Independent Claim 94 words
A method for producing a dry component for a storage stable two component apatitic cement composition, said method comprising: mixing a phosphoric acid source with tricalcium phosphate in the presence of an aqueous solvent, whereby a reaction between said phosphoric acid source and said tricalcium phosphate occurs; and stopping the reaction between said phosphoric acid source and tricalcium phosphate prior to completion by removing substantially all of the free water from said reaction mixture; whereby a dry component comprising tricalcium phosphate at least partially coated with a partially neutralized acidic calcium phosphate is produced.

References Cited (Backward Citations)

USRE33161E Cited
USRE33221E Cited
US4880610A Cited
US5053212A Cited
US5129905A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-03-05 1999-09-04 2000-03-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-03-05 2003-09-04 2004-03-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-03-05 2007-09-04 2008-03-05 $7700.00 Window Closed / Lapsed

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