US3941609A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zinc dust, its preparation, and apparatus for preparing same
Assignee: Asarco LLC
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Filing: 1973-08-22
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Granted: 1976-03-02
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Expires: 1993-08-22
Abstract
Abstract Zinc dust composed of generally spherical zinc dust grains and having a grain size distribution such that at least about 98% of the grains have a grain size less than 15 microns and no more than about 3% of the grains have a grain size less than 2 microns, and especially well adapted for use in corrosion-inhibiting coating compositions where thin but effective protective coatings are desired or required. The zinc dust has a metallic zinc content of about 96%-98%. The corrosion-inhibiting coating compositions, and apparatus and method for the preparation of such zinc dust are also disclosed.
Inventors
- 👤 Melvin Stern
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:26
CPC Classifications
C; C22; C22B; C22B19/00; C22B19/04; B; B22; B22F; B22F9/00; B22F9/02; B22F9/12; C09; C09C; C09C1/00; C09C1/62; C09C1/622; C09C1/625; C09D; C09D5/00; C09D5/08; C09D5/10; C09D5/106; C01; C01P; C01P2004/00; C01P2004/30; C01P2004/32; C01P2004/50; C01P2006/00; C01P2006/80
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
129 words
In a protective coating composition comprising zinc dust and an organic binder, the improvement which comprises utilizing as the zinc dust in said composition, by weight, about 50 to about 95% of a zinc dust comprising generally spherical zinc dust grains and having a grain size distribution as determined by a Coulter Counter such that at least about 98% of the grains have a grain size less than 15 microns, about 85 to about 93% of the grains have a grain size less than 10 microns, about 45 to about 55% of the grains have a grain size less than 5 microns, and no more than about 3% of the grains have a grain size less than 2 microns, said dust having a metallic zinc content of about 95-98%.
Claim 2
Dependent Claim
129 words
In a protective coating composition comprising zinc dust and an organic binder, the improvement which comprises utilizing as the zinc dust in said composition, by weight, about 50 to about 95% of a zinc dust comprising generally spherical zinc dust grains and having a grain size distribution as determined by a Coulter Counter such that at least about 98% of the grains have a grain size less than 15 microns, about 85 to about 93% of the grains have a grain size less than 10 microns, about 45 to about 55% of the grains have a grain size less than 5 microns, and no more than about 3% of the grains have a grain size less than 2 microns, said dust having a metallic zinc content of about 95-98%.
Claim 3
Dependent Claim
50 words
The coating composition of claim 1 wherein about 93% of the grains have a grain size less than 10 microns, about 49% of the grains have a grain size less than 5 microns, and no more than about 2% of the grains have a grain size less than 2 microns.
Claim 4
Dependent Claim
20 words
The coating composition of claim 1 wherein the grains are substantially free of acicular protuberances extending from the grain surfaces.
Claim 5
Dependent Claim
26 words
The coating composition of claim 1 wherein the organic binder is contained therein in amount, by weight, in the range of about 5 to about 45%.
Claim 6
Dependent Claim
15 words
The coating composition of claim 1 also containing a solvent or non-solvent for the binder.
Claim 7
Dependent Claim
12 words
The coating composition of claim 5 containing a solvent for the binder.
Claim 8
Dependent Claim
12 words
The coating composition of claim 5 containing a non-solvent for the binder.
References Cited (Backward Citations)
US3130061A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-02 | 1979-09-01 | 1980-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-02 | 1983-09-01 | 1984-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-02 | 1987-09-01 | 1988-03-02 | $7700.00 | Window Closed / Lapsed |