US5225303A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dry-type toner including waxes release agent for electrophotography
Assignee: Ricoh Co Ltd
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Filing: 1991-10-03
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Granted: 1993-07-06
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Expires: 2011-10-03
Abstract
Abstract A dry-type toner for electrophotography composed of a binder resin, a coloring agent, and a release agent which contains as the main components a carnauba wax substantially free of free aliphatic acids and/or a montan ester wax, and an oxidized rice wax with an acid value of 10 to 30.
Inventors
- 👤 Masami Tomita
- 👤 Toshiki Nanya
- 👤 Yasuaki Iwamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:45
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08702; G03G9/08706; G03G9/08775; G03G9/08782
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
49 words
A dry-type toner for electrophotography comprising a binder resin, a coloring agent, and a release agent, said release agent comprising (a) a carnauba wax substantially free of free aliphatic acids and/or a montan ester wax and (b) an oxidized rice wax with an acid value of 10 to 30.
Claim 2
Dependent Claim
49 words
A dry-type toner for electrophotography comprising a binder resin, a coloring agent, and a release agent, said release agent comprising (a) a carnauba wax substantially free of free aliphatic acids and/or a montan ester wax and (b) an oxidized rice wax with an acid value of 10 to 30.
Claim 3
Dependent Claim
23 words
The dry-type toner for electrophotography as claimed in claim 1, wherein said carnauba wax contains 5 wt.% or less of free aliphatic acids.
Claim 4
Dependent Claim
23 words
The dry-type toner for electrophotography as claimed in claim 1, wherein said carnauba wax contains 2 to 5 wt.% of free aliphatic acids.
Claim 5
Dependent Claim
23 words
The dry-type toner for electrophotography as claimed in claim 1, wherein said montan ester wax has an acid value of 5 to 14.
Claim 6
Dependent Claim
34 words
The dry-type toner for electrophotography as claimed in claim 1, wherein the amount of said carnauba wax and/or montan ester wax is 0.2 to 20 wt.% of the total weight of said dry-type toner.
Claim 7
Dependent Claim
31 words
The dry-type toner for electrophotography as claimed in claim 1, wherein the amount of said oxidized rice wax is 0.2 to 20 wt.% of the total weight of said dry-type toner.
Claim 8
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 9
Dependent Claim
18 words
The dry-type toner for electrophotography as claimed in claim 1, wherein said binder resin is a polyester resin.
Claim 10
Dependent Claim
15 words
The dry-type toner for electrophotography as claimed in claim 1, further comprising a magnetic material.
Claim 11
Dependent Claim
34 words
The dry-type toner for electrophotography as claimed in claim 9, wherein the amount ratio of said magnetic material to said binder resin is 20 to 200 parts by weight to 100 parts by weight.
Claim 12
Dependent Claim
23 words
The dry-type toner for electrophotography as claimed in claim 9, 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) | 1996-07-05 | 1997-01-04 | 1997-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-05 | 2001-01-04 | 2001-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-05 | 2005-01-04 | 2005-07-06 | $7700.00 | Window Closed / Lapsed |