US5079123A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dry-type toner for electrophotography with carnauba wax
Assignee: Ricoh Co Ltd
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Filing: 1990-05-30
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Granted: 1992-01-07
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Expires: 2010-05-30
Abstract
Abstract A dry-type toner for electrophotography comprising a binder resin, a coloring agent, and, as a lubricant, a carnauba wax substantially free of free aliphatic acids. The toner may further comprise a magnetic material, and the resulting toner mixture can be used as a magnetic toner.
Inventors
- 👤 Toshiki Nanya
- 👤 Kimitoshi Yamaguchi
- 👤 Hiromitsu Kawase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:12
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08702; G03G9/08706; G03G9/08708; G03G9/08775; G03G9/08782
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
30 words
A dry-type toner for electrophotography, comprising: (i) a binder resin, (ii) a coloring agent, and (iii) a carnauba wax which contains 1.0 wt. % or less of free aliphatic acids.
Claim 2
Dependent Claim
30 words
A dry-type toner for electrophotography, comprising: (i) a binder resin, (ii) a coloring agent, and (iii) a carnauba wax which contains 1.0 wt. % or less of free aliphatic acids.
Claim 3
Dependent Claim
32 words
The dry-type toner for electrophotography as claimed in claim 1, wherein the amount of said carnauba wax is 0.5 wt. % to 20 wt. % of the weight of said binder resin.
Claim 4
Dependent Claim
48 words
The dry-type toner for electrophotography as claimed in claim 1, wherein said binder resin is a styrene-based resin containing both a high-molecular-weight component and a low-molecular weight component with the ratio (Mw/Mn) of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) being 3.5 or greater.
Claim 5
Dependent Claim
18 words
The dry-type toner for electrophotography as claimed in claim 1, wherein said binder resin is a polyester resin.
Claim 6
Dependent Claim
15 words
The dry-type toner for electrophotography as claimed in claim 1, further comprising a magnetic material.
Claim 7
Dependent Claim
31 words
The dry-type toner for electrophotography as claimed in claim 5, wherein the amount of said magnetic material is 20 to 200 parts by weight of the weight of said binder resin.
Claim 8
Dependent Claim
23 words
The dry-type toner for electrophotography as claimed in claim 5, wherein said magnetic material has an average diameter of 0.1 to 2 μm.
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) | 1995-01-06 | 1995-07-08 | 1996-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-01-06 | 1999-07-08 | 2000-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-01-06 | 2003-07-08 | 2004-01-07 | $7700.00 | Window Closed / Lapsed |