US4810479A
Expired / Lapsed
US
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Preparation of cubic boron nitride using as a flux a fluoronitride
Assignee: Centre National de la Recherche Scientifique
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Filing: 1987-04-15
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Granted: 1989-03-07
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Expires: 2007-04-15
Abstract
Abstract A process for producing cubic boron nitride comprises heating at an elevated temperature and under high pressure a source of boron and a source of nitrogen in the presence of a fluoronitride or a source of fluoronitride.
Inventors
- 👤 Gilles Biardeau
- 👤 Gerard Demazeau
- 👤 Michel Pouchard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:09
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/583; C04B35/5831
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
107 words
A process for preparing cubic boron nitride comprising (i) heating at an elevated temperature and under a high pressure a starting material comprising (1) a source of boron, (2) a source of nitrogen and (3) a fluoronitride, for a time sufficient for forming cubic boron nitride; (ii) quenching the reaction mixture; and (iii) reducing the pressure to atmospheric pressure, wherein (a) said elevated temperature is a temperature sufficient for the appearance of a liquid phase, (b) said high pressure is one at which cubic boron nitride is formed, and (c) said sources of boron and nitrogen are in condensed form under standard conditions of temperature and pressure.
Claim 2
Dependent Claim
107 words
A process for preparing cubic boron nitride comprising (i) heating at an elevated temperature and under a high pressure a starting material comprising (1) a source of boron, (2) a source of nitrogen and (3) a fluoronitride, for a time sufficient for forming cubic boron nitride; (ii) quenching the reaction mixture; and (iii) reducing the pressure to atmospheric pressure, wherein (a) said elevated temperature is a temperature sufficient for the appearance of a liquid phase, (b) said high pressure is one at which cubic boron nitride is formed, and (c) said sources of boron and nitrogen are in condensed form under standard conditions of temperature and pressure.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein said fluoronitride is an alkali fluoronitride, an alkaline earth metal fluoronitride or mixed fluoronitrides of these metals.
Claim 4
Dependent Claim
13 words
The process of claim 1 wherein said fluoronitride is admixed with a fluoride.
Claim 5
Dependent Claim
34 words
The process of claim 1 wherein said fluoronitride is (i) magnesium fluoronitride, (ii) calcium fluoronitride, (iii) barium fluoronitride or (iv) mixed fluoronitrides of (i), (ii) or (iii) with an alkali metal, manganese or zirconium.
Claim 6
Dependent Claim
21 words
The process of claim 1 wherein said source of boron is ammonium fluoroborate, an alkali metal fluoroborate or an alkali borohydride.
Claim 7
Dependent Claim
18 words
The process of claim 1 wherein said source of nitrogen is a nitride, amide or non-oxygenated ammonium salt.
Claim 8
Dependent Claim
16 words
The process of claim 1 whrein said source of boron and nitrogen comprises hexagonal boron nitride.
Claim 9
Dependent Claim
30 words
The process of claim 1 wherein said fluoronitride is present in an amount ranging from 10 to 70 percent by weight relative to the total weight of the starting material.
Claim 10
Dependent Claim
19 words
The process of claim 1 wherein the starting material comprises alternate layers of (1) and (2) and of (3).
Claim 11
Dependent Claim
14 words
The process of claim 1 wherein said pressure is between 4 and 9 GPa.
Claim 12
Dependent Claim
13 words
The process of claim 1 wherein said temperature is at least 1,000° C.
Claim 13
Dependent Claim
12 words
The process of claim 1 wherein said fluoronitride is formed in situ.
Claim 14
Dependent Claim
36 words
A compound of the formula M.sub.3-x M'.sub.x B.sub.2 N.sub.4-x/3 wherein M is an alkaline earth metal, M' is an alkali metal and x is a number, other than 0 but lower than or equal to 1.
Claim 15
Dependent Claim
36 words
A compound of the formula M.sub.3-x M'.sub.x B.sub.2 N.sub.4-x/3 wherein M is an alkaline earth metal, M' is an alkali metal and x is a number, other than 0 but lower than or equal to 1.
Claim 16
Dependent Claim
21 words
The compound of claim 13 wherein M represents Ca, M' represents Li and x is lower than or equal to 0.3.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-03-06 | 1992-09-05 | 1993-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-06 | 1996-09-05 | 1997-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-06 | 2000-09-05 | 2001-03-07 | $7700.00 | Window Closed / Lapsed |