US4497722A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composition for plastic magnets
Assignee: Shin-Etsu Chemical Co Ltd
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Filing: 1984-07-02
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Granted: 1985-02-05
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Expires: 2004-07-02
Abstract
Abstract The plastic magnet composition provided by the invention comprises a thermoplastic resin as a binder and a powder of a metallic or alloy-type magnet which is coated on the particle surface with a phosphorus-containing compound having at least one phosphorus-to-oxygen linkage in a molecule such as phosphoric acid and related compounds. By virtue of the surface coating, the magnet powder is freed from the degradation by air oxidation and the danger of ignition in the molding process so that plastic magnets of high performance can be readily manufactured with safety. The advantages of the coating layer are further increased when the coating layer is formed of a combination of the phosphorus-containing compound and an organic dye compound. An overcoating on the thus coated magnet powder with an organopolysiloxane has an effect of increased lubricity.
Inventors
- 👤 Michinori Tsuchida
- 👤 Tokuji Abe
- 👤 Hajime Kitamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:22
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/06; H01F1/061; H01F1/047; H01F1/053; H01F1/055; H01F1/0551; H01F1/0552; H01F1/0555; H01F1/0558; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
54 words
A plastic magnet composition which comprises: (a) a thermoplastic resin as a binder: and (b) a powder of a metallic or alloy magnet having a coating layer on the surface of the particles formed of a phosphorus-containing compound having at least one phosphorus-to-oxygen linkage in a molecule and uniformly blended with the thermoplastic resin.
Claim 2
Dependent Claim
54 words
A plastic magnet composition which comprises: (a) a thermoplastic resin as a binder: and (b) a powder of a metallic or alloy magnet having a coating layer on the surface of the particles formed of a phosphorus-containing compound having at least one phosphorus-to-oxygen linkage in a molecule and uniformly blended with the thermoplastic resin.
Claim 3
Dependent Claim
42 words
The plastic magnet composition as claimed in claim 1 wherein the coating layer on the surface of the particles of the powder of a metallic or alloy magnet is formed of a combination of the phosphorus-containing compound and an organic dye compound.
Claim 4
Dependent Claim
41 words
The plastic magnet composition as claimed in claim 1 wherein the coating layer on the surface of the particles of the powder of a metallic or alloy magnet is formed of a combination of the phosphorus-containing compound and an organopolysiloxane compound.
Claim 5
Dependent Claim
45 words
The plastic magnet composition as claimed in claim 2 wherein the coating layer on the surface of the particles of the powder of a metallic or alloy magnet is formed of a combination of the phosphorus-containing compound, the organic dye compound and an organopolysiloxane compound.
Claim 6
Dependent Claim
48 words
The plastic magnet composition as claimed in claim 3 wherein the coating layer on the surface of the particles of the powder of a metallic or alloy magnet is composed of an undercoating layer formed of the phosphorus-containing compound and an overcoating layer formed of the organopolysiloxane compound.
Claim 7
Dependent Claim
53 words
The plastic magnet composition as claimed in claim 4 wherein the coating layer on the surface of the particles of the powder of a metallic or alloy magnet is composed of an undercoating layer formed of the phosphorus-containing compound and the organic dye compound and an overcoating layer formed of the organopolysiloxane compound.
Claim 8
Dependent Claim
36 words
The plastic magnet composition as claimed in claim 1 wherein the amount of the phosphorus-containing compound is in the range from 0.01 to 5% by weight based on the powder of the metallic or alloy magnet.
Claim 9
Dependent Claim
43 words
The plastic magnet composition as claimed in claim 1 wherein the phosphorus-containing compound is selected from the group consisting of phosphoric acid, sodium dihydrogen-phosphate, phosphorous acid, sodium hypophosphite, sodium pyrophosphate, potassium pyrophosphate, sodium tripolyphosphate, sodium hydrogenmetaphosphate, isopropyl tris(dioctyl pyrophosphate) titanate and phytic acid.
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) | 1988-02-05 | 1988-08-06 | 1989-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-05 | 1992-08-06 | 1993-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-05 | 1996-08-06 | 1997-02-05 | $7700.00 | Window Closed / Lapsed |