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US5225303A Expired / Lapsed US ⏱️ 0.0 years remaining

Dry-type toner including waxes release agent for electrophotography

Assignee: Ricoh Co Ltd
•
Filing: 1991-10-03
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Granted: 1993-07-06
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Expires: 2011-10-03
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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)

US4845007A Cited
US5053305A Cited
US5047305A Cited

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

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