US5061292A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diamond abrasive and method for producing the same
Assignee: Ishizuka Research Institute Ltd
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Filing: 1989-07-13
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Granted: 1991-10-29
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Expires: 2009-07-13
Abstract
Abstract Diamond abrasive comprising a mass of idiomorphic crystal grits which each have an irregular shaped core of diamond formed under pressure where diamond is thermodynamically favored phase, and a growth layer of diamond and/or diamond-like carbon formed over said core by chemical vapor deposition.
Inventors
- 👤 Chia-Fu Chen
- 👤 Ensei Ko
- 👤 Hiroshi Ishizuka
- 👤 Satoru Hosomi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:03
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/22; C23C16/26; B; B24; B24D; B24D3/00; B24D3/005; B24D3/007; C09; C09K; C09K3/00; C09K3/14; C09K3/1436
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
56 words
Abrasive grits comprising a mass of idiomorphic diamond crystals which each have an irregular shaped core of diamond formed under a pressure at which diamond is the thermodynamicaly favored phase of carbon, and a growth layer of diamond-like carbon, which has at least in part a diamond structure, formed over said core by chemical vapor deposition.
Claim 2
Dependent Claim
56 words
Abrasive grits comprising a mass of idiomorphic diamond crystals which each have an irregular shaped core of diamond formed under a pressure at which diamond is the thermodynamicaly favored phase of carbon, and a growth layer of diamond-like carbon, which has at least in part a diamond structure, formed over said core by chemical vapor deposition.
Claim 3
Dependent Claim
26 words
The diamond abrasive as claimed in claim 1, in which said grits, as measured in average, exhibit an overall size not greater than twice the core.
Claim 4
Dependent Claim
18 words
The diamond abrasive as claimed in claim 2, in which said grits are not greater than 60 microns.
Claim 5
Dependent Claim
32 words
The diamond abrasive as claimed in claim 1, in which said grits exhibit a major to minor axial ratio not greater than 1.3 in average when taken perpendicular to the major axis.
Claim 6
Independent Claim
74 words
A method of producing diamond abrasive, comprising: placing as seeds irregular shaped diamond particles from a high pressure process in a controlled gas mixture comprising hydrogen and carbonaceous substance, exciting the gas mixture to be in plasma state, exposing said particles to the plasma thus causing growth of the particles, regulating the growth rate to a level close to the kinetic equilibrium thus imparting idiomorphic shapes, and recovering the grown diamond as abrasive grits.
Claim 7
Independent Claim
74 words
A method of producing diamond abrasive, comprising: placing as seeds irregular shaped diamond particles from a high pressure process in a controlled gas mixture comprising hydrogen and carbonaceous substance, exciting the gas mixture to be in plasma state, exposing said particles to the plasma thus causing growth of the particles, regulating the growth rate to a level close to the kinetic equilibrium thus imparting idiomorphic shapes, and recovering the grown diamond as abrasive grits.
Claim 8
Dependent Claim
25 words
The method as claimed in claim 5, in which said growth rate is a radial increase on the order of a few microns per hour.
Claim 9
Dependent Claim
23 words
The method as claimed in claim 6, in which said growth rate is a radial increase not greater than 5 microns per hour.
Claim 10
Dependent Claim
23 words
The method as claimed in claim 6, in which said growth rate is a radial increase not greater than 3 microns per hour.
Claim 11
Dependent Claim
18 words
The method as claimed in claim 5, in which said seeds exhibit an average size of 20 microns.
Claim 12
Dependent Claim
22 words
The method as claimed in claim 5, in which said grits are recovered before an average size exceeds twice the core size.
Claim 13
Dependent Claim
10 words
Abrasive grits made according to the process of claim 5.
References Cited (Backward Citations)
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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) | 1994-10-28 | 1995-04-29 | 1995-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-10-28 | 1999-04-29 | 1999-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-10-28 | 2003-04-29 | 2003-10-29 | $7700.00 | Window Closed / Lapsed |