US4401741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
One-component type developer
Assignee: Kyocera Mita Industrial Co Ltd
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Filing: 1982-05-27
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Granted: 1983-08-30
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Expires: 2002-05-27
Abstract
Abstract Disclosed is an electrically insulating, magnetic one-component type developer comprising an electrically insulating binder medium, and a magnetic material powder and a charge control agent dispersed in the binder medium, wherein the charge control agent comprises a negative or positive charge control agent and a charge control agent having a polarity opposite to that of said charge control agent at a weight ratio of from 1/0.05 to 1/1.5.
Inventors
- 👤 Nobuhiro Miyakawa
- 👤 Kouzi Maekawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:08
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/09; G03G9/0906; G03G9/091; G03G9/0918; G03G9/097; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/104
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
66 words
An electrically insulating, magnetic one-component type developer comprising an electrically insulating binder medium, and a magnetic material powder and a charge control agent dispersed in the binder medium, wherein the charge control agent comprises a negative or positive charge control agent and a charge control agent having a polarity opposite to that of said charge control agent at a weight ratio of from 1/0.05 to 1/1.5.
Claim 2
Dependent Claim
66 words
An electrically insulating, magnetic one-component type developer comprising an electrically insulating binder medium, and a magnetic material powder and a charge control agent dispersed in the binder medium, wherein the charge control agent comprises a negative or positive charge control agent and a charge control agent having a polarity opposite to that of said charge control agent at a weight ratio of from 1/0.05 to 1/1.5.
Claim 3
Dependent Claim
32 words
A developer as set forth in claim 1, wherein the negative charge control agent and positive charge control agent are used in combination at a weight ratio of from 1/0.1 to 1/1.
Claim 4
Dependent Claim
37 words
A developer as set forth in claim 1 or 2, wherein the negative charge control agent is a complex salt azo dye containing chromium, iron or cobalt, and the positive charge control agent is an oil-soluble dye.
Claim 5
Dependent Claim
33 words
A developer as set forth in claim 1 or 2, wherein the total amount of the charge control agents is 0.5 to 10% by weight based on the amount of the binder medium.
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) | 1986-08-29 | 1987-02-28 | 1987-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-29 | 1991-02-28 | 1991-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-29 | 1995-02-28 | 1995-08-30 | $7700.00 | Window Closed / Lapsed |