US4650699A
Expired / Lapsed
US
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Thixotropic alumina coating compositions, parts and methods
Assignee: Sermetel
•
Filing: 1985-07-26
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Granted: 1987-03-17
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Expires: 2005-07-26
Abstract
Abstract A stable thixotropic coating composition especially suitable for dipspin application having an aqueous acid binder solution which comprises phosphate ions and ions of the group of chromate ions or molybdate ions, and a dispersible hydrated alumina having a boehmite type crystal lattice.
Inventors
- 👤 Mark F. Mosser
- 👤 Kevin Eddinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:37
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/73; C23C22/74
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
102 words
A method for coating a metal part by dipspinning which comprises (a) contacting the metal surface to be coated with a thixotropic coating composition which comprises (1) an aqueous acid coating solution which solution comprises phosphate ions and ions of the group consisting of chromate ions or molybdate ions, and (2) a hydrated alumina having a boehmite type crystal lattice and being dispersible in the acid solution, (b) subjecting said part having said surface coating to a rapid spinning movement, whereby the composition flows onto the surface to be coated, (c) stopping the spinning and (d) curing the coating on said surface.
Claim 2
Independent Claim
102 words
A method for coating a metal part by dipspinning which comprises (a) contacting the metal surface to be coated with a thixotropic coating composition which comprises (1) an aqueous acid coating solution which solution comprises phosphate ions and ions of the group consisting of chromate ions or molybdate ions, and (2) a hydrated alumina having a boehmite type crystal lattice and being dispersible in the acid solution, (b) subjecting said part having said surface coating to a rapid spinning movement, whereby the composition flows onto the surface to be coated, (c) stopping the spinning and (d) curing the coating on said surface.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said thixotropic coating composition includes fumed alumina.
Claim 4
Dependent Claim
22 words
The method of claim 2 wherein the fumed alumina is present in the amount of 0.25 to 10% by weight of composition.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein said thixotropic coating composition includes a nonionic surfactant.
Claim 6
Dependent Claim
26 words
The method of claim 4 wherein the amount of nonionic surfactant is in the range of about 0.01 to about 0.5% by weight of total solids.
Claim 7
Dependent Claim
21 words
The method of claim 1 wherein the pH range of the thixotropic coating composition is from about 0.5 to about 3.0.
Claim 8
Dependent Claim
21 words
The method of claim 1 wherein said thixotropic coating composition has a viscosity range from about 1,000 to about 50,000 cp.
Claim 9
Dependent Claim
17 words
The method of claim 7 wherein the viscosity range is from about 1,500 to about 10,000 cp.
Claim 10
Dependent Claim
50 words
A part coated with the cured composition which comprises (a) an aqueous acid coating solution which solution comprises phosphate ions and ions of the group consisting of chromate ions or molybdate ions, and (b) a hydrated alumina having a boehmite type crystal lattice and being dispersible in the acid solution.
Claim 11
Dependent Claim
50 words
A part coated with the cured composition which comprises (a) an aqueous acid coating solution which solution comprises phosphate ions and ions of the group consisting of chromate ions or molybdate ions, and (b) a hydrated alumina having a boehmite type crystal lattice and being dispersible in the acid solution.
Claim 12
Dependent Claim
13 words
The coated part of claim 9 wherein said coating composition contains fumed alumina.
Claim 13
Dependent Claim
25 words
The coated part of claim 10 wherein the fumed alumina is present in the amount of 0.25 to 10% by weight of said coating composition.
Claim 14
Dependent Claim
17 words
The coated part of claim 9 wherein said coating composition contains a nonionic surfactant and fumed silica.
Claim 15
Dependent Claim
30 words
The coated part of claim 12 wherein the amount of fumed silica in said coating composition is in the range of about 0.25 to 10% by weight of total solids.
Claim 16
Dependent Claim
45 words
The coated part of claim 9 wherein said coating composition includes a particulate solid material selected from the group consisting of aluminum, zinc, an oxide of the following: silicon, zirconium, beryllium or aluminum, iron, chromium, a refractory carbide, nitride, silicide, or boride, or alloy thereof.
Claim 17
Dependent Claim
17 words
The coated part of claim 14 wherein the particulate solid material is aluminum or an aluminum alloy.
Claim 18
Dependent Claim
21 words
The coated part of claim 15 wherein the particulate solid material is of an average particle size below about 10 microns.
Claim 19
Dependent Claim
17 words
The coated part of claim 9 wherein said coating composition comprises a gel of a reduced chromate.
Claim 20
Dependent Claim
17 words
The coated part of claim 17 wherein said gel is of a reduced water-soluble or water-insoluble chromate.
Claim 21
Dependent Claim
23 words
The coated part of claim 17 wherein said gel is an insoluble Cr(OH) 3 and/or a Cr 2 (CrO 4 ) 3 gel.
References Cited (Backward Citations)
US3804663A
Cited
US4267212A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-03-16 | 1990-09-15 | 1991-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-16 | 1994-09-15 | 1995-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-16 | 1998-09-15 | 1999-03-17 | $7700.00 | Window Closed / Lapsed |