US4514485A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developer for electrophotography having carrier particles, toner particles and electroconductive fine powders
Assignee: Canon Inc
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Filing: 1982-08-19
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Granted: 1985-04-30
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Expires: 2002-08-19
Abstract
Abstract An electrophotographic developer comprises magnetic particles coated with a low surface energy resin, toner particles and electroconductive fine powders. This developer can develop solid areas uniformly and does not form fog.
Inventors
- 👤 Hisayuki Ushiyama
- 👤 Hisayuki Ochi
- 👤 Tatsuo Miyamae
- 👤 Katsutoshi Wakamiya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:08
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/10; G03G9/113; G03G9/1132; G03G9/097; G03G9/09708; G03G9/1133; G03G9/1134
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
30 words
An electrophotographic developer which comprises magnetic particles coated with a low surface energy resin, toner particles and electroconductive fine powders from 0.001-1 micron selected from tin oxide and zinc oxide.
Claim 2
Dependent Claim
30 words
An electrophotographic developer which comprises magnetic particles coated with a low surface energy resin, toner particles and electroconductive fine powders from 0.001-1 micron selected from tin oxide and zinc oxide.
Claim 3
Dependent Claim
21 words
An electrophotographic developer according to claim 1 in which the low surface energy resin has a surface tension of 15-30 dyne/cm.
Claim 4
Dependent Claim
16 words
An electrophotographic developer according to claim 1 in which the low surface energy resin is fluoroplastics.
Claim 5
Dependent Claim
22 words
An electrophotographic developer according to claim 3 in which the thickness of the fluoroplastics coating on the magnetic particles is 5-20 microns.
Claim 6
Dependent Claim
17 words
An electrophotographic developer according to claim 1 in which the low surface energy resin is silicone resin.
Claim 7
Dependent Claim
23 words
An electrophotographic developer according to claim 5 in which the thickness of the silicone resin coating on the magnetic particles is 0.5-2 microns.
Claim 8
Dependent Claim
20 words
An electrophotographic developer according to claim 1 in which the resistivity of the electroconductive fine powders is 0.1-10 5 ohm.cm.
Claim 9
Dependent Claim
25 words
An electrophotographic developer according to claim 1 in which the amount of the electroconductive fine powders is 1-10% base on the weight of the toner.
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) | 1988-04-29 | 1988-10-29 | 1989-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-29 | 1992-10-29 | 1993-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-29 | 1996-10-29 | 1997-04-30 | $7700.00 | Window Closed / Lapsed |