US5120366A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite ferrite material
Assignee: Panasonic Holdings Corp
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Filing: 1991-09-09
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Granted: 1992-06-09
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Expires: 2011-09-09
Abstract
Abstract A composite ferrite material is provided. The composite ferrite material obtained from a mixture of a magnetic ferrite powder with high crystallinity, prepared by firing at a prescribed temperature, and a glass powder, having a softening temperature lower than said firing temperature, by heat treatment of said mixture at a temperature which is higher than, or equal to said softening temperature of said glass powder and lower than, or equal to said firing temperature, to effect the binding of said magnetic ferrite powder by said glass material. The composite ferrite material has excellent magnetic characteristics and can be obtained in a form of the desired dimensions with high accuracy.
Inventors
- 👤 Shinji Harada
- 👤 Tadashi Kawamata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:46
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/10; H01F1/11; H01F1/113; H01F1/12; H01F1/34; H01F1/36; H01F1/37
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
93 words
A method for the preparation of a composite ferrite material, comprising: mixing a sintered magnetic ferrite powder with high crystallinity, and a glass powder with a softening temperature lower than the sintering temperature of said ferrite powder, subjecting said mixture to press forming, and subjecting said press-formed mass to heat treatment at a temperature which is higher than or equal to the softening temperature of said glass powder and lower than said sintering temperature to fuse said glass powder contained in said mass thereby binding said magnetic ferrite powder with said fused glass.
Claim 2
Independent Claim
93 words
A method for the preparation of a composite ferrite material, comprising: mixing a sintered magnetic ferrite powder with high crystallinity, and a glass powder with a softening temperature lower than the sintering temperature of said ferrite powder, subjecting said mixture to press forming, and subjecting said press-formed mass to heat treatment at a temperature which is higher than or equal to the softening temperature of said glass powder and lower than said sintering temperature to fuse said glass powder contained in said mass thereby binding said magnetic ferrite powder with said fused glass.
Claim 3
Dependent Claim
22 words
A method according to claim 1, wherein said magnetic ferrite powder is composed of granules with at least two different size distributions.
Claim 4
Dependent Claim
17 words
A method according to claim 1, wherein said sintering temperature is in the range of 1000°-1400° C.
Claim 5
Dependent Claim
19 words
A method according to claim 1, wherein said softening temperature of said glass powder is 650° C. or lower.
Claim 6
Dependent Claim
18 words
A method according to claim 1, wherein the temperature of said heat treatment is 800° C. or higher.
Claim 7
Dependent Claim
12 words
A method according to claim 1, wherein said glass contains zinc oxide.
Claim 8
Dependent Claim
38 words
A method according to claim 1, wherein said glass powder is used in an amount of 0.3 to 30% by weight based on the total weight of said glass powder and said magnetic ferrite powder with high crystallinity.
Claim 9
Independent Claim
116 words
A method for the preparation of a composite ferrite material, comprising: mixing a sintered magnetic ferrite powder with high crystallinity, and a glass powder with a softening temperature lower than the sintering temperature of said ferrite powder, subjecting said mixture to press forming, and simultaneous heat treatment at a temperature which is higher than or equal to the softening temperature of said glass powder and lower than said sintering temperature and thereby fusing said glass powder thus effecting the binding of said magnetic ferrite powder by said fused glass, and firing the obtained mass after said heat treatment at a temperature which is lower than or equal to the sintering temperature of said magnetic ferrite powder.
Claim 10
Independent Claim
116 words
A method for the preparation of a composite ferrite material, comprising: mixing a sintered magnetic ferrite powder with high crystallinity, and a glass powder with a softening temperature lower than the sintering temperature of said ferrite powder, subjecting said mixture to press forming, and simultaneous heat treatment at a temperature which is higher than or equal to the softening temperature of said glass powder and lower than said sintering temperature and thereby fusing said glass powder thus effecting the binding of said magnetic ferrite powder by said fused glass, and firing the obtained mass after said heat treatment at a temperature which is lower than or equal to the sintering temperature of said magnetic ferrite powder.
Claim 11
Dependent Claim
22 words
A method according to claim 8, wherein said magnetic ferrite powder is composed of granules with at least two different size distributions.
Claim 12
Dependent Claim
17 words
A method according to claim 8, wherein said firing temperature is in the range of 1000°-1400° C.
Claim 13
Dependent Claim
19 words
A method according to claim 8, wherein said softening temperature of said glass powder is 650° C. or lower.
Claim 14
Dependent Claim
18 words
A method according to claim 8, wherein the temperature of said heat treatment is 800° C. or higher.
Claim 15
Dependent Claim
12 words
A method according to claim 8, wherein said glass contains zinc oxide.
Claim 16
Dependent Claim
38 words
A method according to claim 8, wherein said glass powder is used in an amount of 0.3 to 30% by weight based on the total weight of said glass powder and said magnetic ferrite powder with high crystallinity.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-09 | 1995-12-09 | 1996-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-09 | 1999-12-09 | 2000-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-09 | 2003-12-09 | 2004-06-09 | $7700.00 | Window Closed / Lapsed |