Patent US5009674A successfully refreshed from Google Patents.
US5009674A
Expired / Lapsed
US
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Abrasives
Assignee: Imerys Fused Minerals Laufenburg GmbH
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Filing: 1989-11-02
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Granted: 1991-04-23
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Expires: 2009-11-02
Abstract
Abstract An abrasive grain with an aluminum oxide base which is distinguished by good throwing power and by a good capability of being integrated in flexible abrasives or in grinding wheels with artificial resin bonding.
Inventors
- 👤 Reiner Kunz
- 👤 Albert Babl
- 👤 Ales Zahradnicek
- 👤 Rainer Dietrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:57
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
100 words
Abrasive grain having an aluminum oxide base, comprising the aluminum oxide base with a hygroscopic salt coated on its surface, the amount of said hygroscopic salt being 0.001 to 5.0 percent by weight relative to the amount of the abrasive grain, the specific resistance of the treated abrasive grain, measured in grain beds, being smaller than 3.5×10 10 ohms×cm, and the hygroscopic salt is a carbonate, hydrogen carbonate, sulfate, nitrate, phosphate, fluoride or chloride of a metal of the first, second or third main group or of the first or second series of the transition metals of the periodic table.
Claim 2
Dependent Claim
100 words
Abrasive grain having an aluminum oxide base, comprising the aluminum oxide base with a hygroscopic salt coated on its surface, the amount of said hygroscopic salt being 0.001 to 5.0 percent by weight relative to the amount of the abrasive grain, the specific resistance of the treated abrasive grain, measured in grain beds, being smaller than 3.5×10 10 ohms×cm, and the hygroscopic salt is a carbonate, hydrogen carbonate, sulfate, nitrate, phosphate, fluoride or chloride of a metal of the first, second or third main group or of the first or second series of the transition metals of the periodic table.
Claim 3
Dependent Claim
25 words
The abrasive grain according to claim 1 wherein the amount of substance if 0.1 to 0.5 percent b weight relative to the amount of abrasive.
Claim 4
Dependent Claim
29 words
The abrasive grain according to claim 1 wherein the specific resistance of the treated abrasive grain, measured in grain beds, is between 0.05×10 10 and 2/5 ×10 10 ohms×cm.
Claim 5
Dependent Claim
26 words
The abrasive grain according to claim 1 wherein sodium carbonate, sodium hydrogen carbonate, magnesium chloride, calcium nitrate or iron chloride is used as the hygroscopic salt.
Claim 6
Dependent Claim
49 words
Abrasive produced by coating a base, which exhibits an adhesion promoter, with an abrasive grain according to claim 1 which has been coated with a hygroscopic salt in the electrical field of 20,000 to 10,000 ##EQU2## at a relative humidity of 30 to 90 percent in the processing range.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-04-22 | 1994-10-22 | 1995-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-04-22 | 1998-10-22 | 1999-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-04-22 | 2002-10-22 | 2003-04-23 | $7700.00 | Window Closed / Lapsed |