US4911855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High magnetic strength magnets containing a flexible acrylate-amps binder
Assignee: Aerojet Rocketdyne Holdings Inc
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Filing: 1989-01-30
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Granted: 1990-03-27
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Expires: 2009-01-30
Abstract
Abstract An emulsion acrylate copolymer is provided which unexpectedly is an effective magnetic binder inasmuch as it can be loaded with high amounts of one or more magnetic particles such as ferrite or ferrite containing materials to provide a flexible permanent type magnetic composition of high magnetic energy. The copolymer is made from an alkyl acrylate and a salt of 2-acrylamido-2-methylpropane sulfonic acid (AMPS). A carboxylated ethoxy alkyl phenol surfactant is utilized which provides good processability and permits a blend of the magnetic particles with the emulsion acrylate copolymer to be precipitated from a latex solution by high shear mixing. Flexible high magnetic energy magnets can thus be made and utilized in various applications such as refrigerator doors, electrical motors, and the like.
Inventors
- 👤 Vincent M. Rasicci
- 👤 John F. Mioduszeski
- 👤 Cecil R. Gurganus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:59
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/34; H01F1/36; H01F1/37; H01F1/375; H01F1/032; H01F1/04; H01F1/06; H01F1/08; H01F1/083
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
127 words
A flexible high magnetic energy magnet, comprising from about 500 to about 1,200 parts by weight of magnetic particles per 100 parts by weight of an acrylate copolymer binder comprising: in copolymerized form (1) an acrylate monomer having the formula ##STR4## wherein R 1 is an alkyl having from 1 to 10 carbon atoms or a corresponding methacrylate, and (2) an AMPS monomer having the formula ##STR5## wherein M is an alkaline metal or NH 4 , the amount of said acrylate monomer being from about 90 percent to about 99.8 percent by weight and the amount of said AMPS monomer being from about 0.2 percent to about 10 percent by weight, said percentages based upon the total weight of said acrylate monomer and said AMPS monomer.
Claim 2
Dependent Claim
127 words
A flexible high magnetic energy magnet, comprising from about 500 to about 1,200 parts by weight of magnetic particles per 100 parts by weight of an acrylate copolymer binder comprising: in copolymerized form (1) an acrylate monomer having the formula ##STR4## wherein R 1 is an alkyl having from 1 to 10 carbon atoms or a corresponding methacrylate, and (2) an AMPS monomer having the formula ##STR5## wherein M is an alkaline metal or NH 4 , the amount of said acrylate monomer being from about 90 percent to about 99.8 percent by weight and the amount of said AMPS monomer being from about 0.2 percent to about 10 percent by weight, said percentages based upon the total weight of said acrylate monomer and said AMPS monomer.
Claim 3
Dependent Claim
33 words
A flexible high magnetic energy magnet, according to claim 1 comprising from about 800 to about 1,200 parts by weight of magnetic particles per 100 parts by weight of the acrylate copolymer binder.
Claim 4
Dependent Claim
33 words
A flexible high magnetic energy magnet, according to claim 1 comprising from about 900 to about 1,200 parts by weight of magnetic particles per 100 parts by weight of the acrylate copolymer binder.
Claim 5
Dependent Claim
33 words
A flexible high magnetic energy magnet, according to claim 1 comprising from about 900 to about 1,200 parts by weight of magnetic particles per 100 parts by weight of the acrylate copolymer binder.
Claim 6
Dependent Claim
52 words
A flexible high magnetic energy magnet, according to claim 1 comprising from about 900 to about 1,200 parts by weight of magnetic particles per 100 parts by weight of the acrylate copolymer binder, said magnetic particles having from about 1 percent to about 90 percent by weight of ferrite containing particles therein.
References Cited (Backward Citations)
US3124725A
Cited
US3282909A
Cited
US3956440A
Cited
US3933536A
Cited
US4292261A
Cited
US4190548A
Cited
US4200547A
Cited
US4327346A
Cited
US4373056A
Cited
US4496303A
Cited
US4600521A
Cited
US4746687A
Cited
US4788228A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-26 | 1993-09-25 | 1994-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-26 | 1997-09-25 | 1998-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-26 | 2001-09-25 | 2002-03-27 | $7700.00 | Window Closed / Lapsed |