US5354639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Color toner for developing electrostatic image comprising a polyalkylene having a crystallinity of 10-50%
Assignee: Canon Inc
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Filing: 1992-08-28
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Granted: 1994-10-11
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Expires: 2012-08-28
Abstract
Abstract A color toner for developing electrostatic images is formed of color toner particles each including a binder resin, a polyalkylene, and a colorant. The color toner particles are formed by suspension polymerization. The polyalkylene is characterized by having a crystallinity of 10-50% and a melting enthalpy (as measured by a differential scanning calorimeter) of at most 35 cal/g. The color toner is characterized by an improved fixability without causing offset especially at a relatively low temperature and suitable for providing a transparency film for an overhead projection.
Inventors
- 👤 Takashige Kasuya
- 👤 Takayuki Nagatsuka
- 👤 Tatsuya Nakamura
- 👤 Makoto Kanbayashi
- 👤 Tatsuhiko Chiba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:06
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08702; G03G9/08704; G03G9/08784; G03G9/08786; G03G9/093; G03G9/0935; G03G9/09357; G03G9/09364
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
133 words
A color toner for developing electrostatic images, comprising: color toner particles each comprising a binder resin, a polyalkylene, and a colorant; wherein the color toner particles have been obtained by suspension polymerization of a polymerizable monomer composition including an α,β- ethylenically unsaturated monomer, a polar polymer or copolymer, the polyalkylene and the colorant by dispersion within an aqueous medium and polymerized in the presence of a polymerization initiator; wherein each color toner particle has a capsule-like structure comprising a core substance comprising the polyalkylene and an outer shell covering the core substance as confirmed by observation of a section thereof by stained microtomy through a transmission electron microscope; and wherein the polyalkylene has a crystallinity of 10-50% and a melting enthalpy (as measured by a differential scanning calorimeter) of at most 35 cal/g.
Claim 2
Dependent Claim
133 words
A color toner for developing electrostatic images, comprising: color toner particles each comprising a binder resin, a polyalkylene, and a colorant; wherein the color toner particles have been obtained by suspension polymerization of a polymerizable monomer composition including an α,β- ethylenically unsaturated monomer, a polar polymer or copolymer, the polyalkylene and the colorant by dispersion within an aqueous medium and polymerized in the presence of a polymerization initiator; wherein each color toner particle has a capsule-like structure comprising a core substance comprising the polyalkylene and an outer shell covering the core substance as confirmed by observation of a section thereof by stained microtomy through a transmission electron microscope; and wherein the polyalkylene has a crystallinity of 10-50% and a melting enthalpy (as measured by a differential scanning calorimeter) of at most 35 cal/g.
Claim 3
Dependent Claim
15 words
The color toner according to claim 1, wherein said polyalkylene has a crystallinity of 20-30%.
Claim 4
Dependent Claim
19 words
The color toner according to claim 1, wherein said polyalkylene has a melting enthalpy of at most 25 cal/g.
Claim 5
Dependent Claim
17 words
The color toner according to claim 1, wherein said polyalkylene has a melting point of 30°-150° C.
Claim 6
Dependent Claim
17 words
The color toner according to claim 1, wherein said polyalkylene has a melting point of 50°-100° C.
Claim 7
Dependent Claim
27 words
The color toner according to claim 1, wherein said polyalkylene is contained in a proportion of 2-50 wt. parts per 100 wt. parts of the binder resin.
Claim 8
Dependent Claim
27 words
The color toner according to claim 1, wherein said polyalkylene is contained in a proportion of 5-35 wt. parts per 100 wt. parts of the binder resin.
Claim 9
Dependent Claim
30 words
The color toner according to claim 1, wherein the core substance comprises 50 wt. % or more of the polyalkylene as measured at a central part of each toner particle.
Claim 10
Dependent Claim
21 words
The color toner according to claim 1, wherein said polyalkylene comprises a homopolymer or copolymer of a linear or branched olefin.
Claim 11
Dependent Claim
33 words
The color toner according to claim 1, wherein said polyalkylene comprises a graft copolymer obtained by graft-polymerizing a comonomer onto a Polyalkylene main chain, followed by heating and coating at a controlled rate.
Claim 12
Dependent Claim
24 words
The color toner according to claim 1, wherein said polyalkylene comprises a graft copolymer obtained by graft-polymerizing styrene monomer onto polyethylene, followed by quenching.
Claim 13
Dependent Claim
57 words
The color toner according to claim 1, wherein during the suspension polymerization, the polymerizable monomer composition is heated until the polalkylene is dissolved or melted to be uniformly dissolved or dispersed therein, and the monomer composition is dispersed within the aqueous medium to form droplets which are subjected to polymerization in the presence of the polymerization initiator.
Claim 14
Dependent Claim
32 words
The color toner according to claim 12, wherein said polymerizable monomer composition further includes a polar polymer in an amount of 0.1-10 wt. parts per 100 wt. parts of the polymerizable monomer.
Claim 15
Dependent Claim
26 words
The color toner according to claim 1, wherein said binder resin comprises principally a polymer of an ethylenically unsaturated monomer and further comprises a polar polymer.
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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) | 1997-10-10 | 1998-04-11 | 1998-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-10-10 | 2002-04-11 | 2002-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-10-10 | 2006-04-11 | 2006-10-11 | $7700.00 | Window Closed / Lapsed |