← Back to Patent Explorer
US5759733A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid developer for electrostatic electrophotography

Assignee: Ricoh Co Ltd
•
Filing: 1992-01-13
•
Granted: 1998-06-02
•
Expires: 2012-01-13
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A liquid developer for use in electrophotography is disclosed, which comprises (i) a toner comprising as the main toner components a colorant, a resin, and a polyolefin resin having an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 cps, and (ii) a carrier liquid in which the toner is dispersed. The polyolefin resin and the colorant in the liquid developer may constitute an integral flushing colorant which is prepared by subjecting the resin and the colorant to flushing processing.

Inventors

  • 👤 Kazuo Tsubuko
  • 👤 Shinichi Kuramoto
  • 👤 Toshiki Nanya
  • 👤 Kazuhiko Umemura
  • 👤 Kayoko Nagai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 00:21
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/13; G03G9/131

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 60 words
A liquid developer for use in electrophotography comprising: a toner comprising as the main toner components a colorant and a polyethylene oxide or polypropylene oxide resin having an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 cps; and an aliphatic hydrocarbon carrier liquid in which said toner is dispersed.
Claim 2
Dependent Claim 60 words
A liquid developer for use in electrophotography comprising: a toner comprising as the main toner components a colorant and a polyethylene oxide or polypropylene oxide resin having an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 cps; and an aliphatic hydrocarbon carrier liquid in which said toner is dispersed.
Claim 3
Dependent Claim 135 words
A liquid developer for use in electrophotography comprising: a toner comprising as the main toner components a colorant, polyethylene oxide or polypropylene oxide resin having an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 and a second resin different from said polyethylene oxide or polypropylene oxide resin, the amount of the polyethylene oxide or propylene oxide resin being in the range of 10 to 90 wt. % of the total of said second resin and said polyethylene oxide or polypropylene oxide resin, said second resin being selected from the group consisting of a polyolefin different from polyethylene oxide or polypropylene oxide, acrylic resin, rosin-modified resin, styrene-butadiene resin, natural resins and paraffin wax; and an aliphatic hydrocarbon carrier liquid in which said toner is dispersed.
Claim 4
Dependent Claim 135 words
A liquid developer for use in electrophotography comprising: a toner comprising as the main toner components a colorant, polyethylene oxide or polypropylene oxide resin having an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 and a second resin different from said polyethylene oxide or polypropylene oxide resin, the amount of the polyethylene oxide or propylene oxide resin being in the range of 10 to 90 wt. % of the total of said second resin and said polyethylene oxide or polypropylene oxide resin, said second resin being selected from the group consisting of a polyolefin different from polyethylene oxide or polypropylene oxide, acrylic resin, rosin-modified resin, styrene-butadiene resin, natural resins and paraffin wax; and an aliphatic hydrocarbon carrier liquid in which said toner is dispersed.
Claim 5
Dependent Claim 33 words
The liquid developer as claimed in claim 1, wherein said polyolefin resin has an acid value of from 10 to 30 and a melt viscosity at 200° C. of 500 to 10,000 cps.
Claim 6
Dependent Claim 15 words
The liquid developer as claimed in claim 1, wherein said polyolefin resin is polyethylene oxide.
Claim 7
Dependent Claim 67 words
A liquid developer for use in electrophotography, comprising: a toner comprising a colorant and a binder resin selected from the group consisting of polyethylene oxide and polypropylene oxide, with the provisos that said binder resin has an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 cps, and a carrier liquid in which said toner is dispersed.
Claim 8
Dependent Claim 67 words
A liquid developer for use in electrophotography, comprising: a toner comprising a colorant and a binder resin selected from the group consisting of polyethylene oxide and polypropylene oxide, with the provisos that said binder resin has an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 cps, and a carrier liquid in which said toner is dispersed.
Claim 9
Dependent Claim 73 words
A liquid developer for use in electrophotography comprising: a toner comprising as the main toner components a colorant and a polyolefin resin having an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 cps, said polyolefin resin consisting of an ethylene-vinylpyridine-maleic acid copolymer with a respective component weight ratio of 90/5/5; and an aliphatic hydrocarbon carrier liquid in which said toner is dispersed.
Claim 10
Dependent Claim 73 words
A liquid developer for use in electrophotography comprising: a toner comprising as the main toner components a colorant and a polyolefin resin having an acid value of from 5 to 50 and a melt viscosity at 200° C. of from 100 to 15,000 cps, said polyolefin resin consisting of an ethylene-vinylpyridine-maleic acid copolymer with a respective component weight ratio of 90/5/5; and an aliphatic hydrocarbon carrier liquid in which said toner is dispersed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-06-01 2001-12-01 2002-06-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-06-01 2005-12-01 2006-06-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-06-01 2009-12-01 2010-06-02 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag