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US5258255A
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Electrostatic charge image developer composition
Assignee: Kao Corp
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Filing: 1992-07-16
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Granted: 1993-11-02
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Expires: 2012-07-16
Abstract
Abstract A developer composition for an electrostatic charge image, which comprises a toner comprising a binder resin and a coloring agent, and 0.1 to 1.0% by weight of fine polymer particles with a glass transition temperature of 90° C. or higher deposited on the surface of the toner, the binder resin comprising, as a main component, a polyester resin with an OHV/AV value of 1.2 or more wherein OHV and AV represent the hydroxyl value and acid value of the polyester resin, respectively.
Inventors
- 👤 Jun Shimizu
- 👤 Masayoshi Nawa
- 👤 Yoshihiro Fukushima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:44
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/097; G03G9/087; G03G9/08742; G03G9/08755
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
82 words
A developer composition for an electrostatic charge image, which comprises a toner comprising a binder resin and a coloring agent, and 0.1 to 1.0% by weight of fine polymer particles with a glass transition temperature of 90° C. or higher deposited on the surface of said toner, said binder resin comprising, as a main component, a polyester resin with an OHV/AV value of 1.2 or more wherein OHV and AV represent the hydroxyl value and acid value of said polyester resin, respectively.
Claim 2
Dependent Claim
82 words
A developer composition for an electrostatic charge image, which comprises a toner comprising a binder resin and a coloring agent, and 0.1 to 1.0% by weight of fine polymer particles with a glass transition temperature of 90° C. or higher deposited on the surface of said toner, said binder resin comprising, as a main component, a polyester resin with an OHV/AV value of 1.2 or more wherein OHV and AV represent the hydroxyl value and acid value of said polyester resin, respectively.
Claim 3
Dependent Claim
34 words
A composition as in claim 1, wherein said fine polymer particles are particles of at least one polymer selected from the group consisting of a acrylic polymer, a vinyl polymer and an acrylic-vinyl copolymer.
Claim 4
Dependent Claim
13 words
A composition as in claim 2, wherein said polymer is an acrylic-vinyl copolymer.
Claim 5
Dependent Claim
14 words
A composition as in claim 3, wherein said copolymer is a methyl methacrylate-styrene copolymer.
Claim 6
Dependent Claim
21 words
A composition as in claim 1, wherein said fine polymer particles have an average particle size of 0.05 to 1.0 μm.
Claim 7
Dependent Claim
21 words
A composition as in claim 5, wherein said average particle size of the fine polymer particles is 0.1 to 0.5 μm.
Claim 8
Dependent Claim
21 words
A composition as in claim 1, wherein said glass transition temperature of the fine polymer particles is 100° C. or higher.
Claim 9
Dependent Claim
27 words
A composition as in claim 1, wherein the amount of the fine polymer particles deposited on the surface of the toner is 0.05 to 0.30% by weight.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-11-01 | 1997-05-03 | 1997-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-11-01 | 2001-05-03 | 2001-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-11-01 | 2005-05-03 | 2005-11-02 | $7700.00 | Window Closed / Lapsed |