US4973541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic latent image developer comprising capsule toner of irregular shape, wrinkled surface
Assignee: Minolta Co Ltd
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Filing: 1989-08-02
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Granted: 1990-11-27
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Expires: 2009-08-02
Abstract
Abstract The present invention provides a developer for developing electrostatic latent image which comprises capsule toners and carriers; said capsule toner having many wrinkles or hollows and upheavals and containing liquid in a shell, and the carriers have no sharp edge or a lower specific gravity, the image copied by the developer can be fixed by pressure under low temperature.
Inventors
- 👤 Toshitaro Kohri
- 👤 Junji Machida
- 👤 Masahiro Anno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:49
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/16; G03G9/08; G03G9/093; G03G9/09307; G03G9/09314; G03G9/09328; G03G9/09392; G03G9/10; Y; Y10; Y10S; Y10S524/00; Y10S524/901; Y10S525/00; Y10S525/934; Y10S526/00; Y10S526/934; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985; Y10T428/2987
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
106 words
A developer for developing electrostatic latent image, which comprises: (1) a capsule toner having an irregular shape and a wrinkled surface as substantially depicted in FIG. 2, in which a core material comprises at least, a solvent of high boiling point and a resin for fixing and a coloring agent, both of which are dissolved in or dispersed in the solvent, wherein the core material is enclosed in a shell material containing a chargeable resin, said capsule toner having a mean particle diameter of from 3 to 25 microns; and (2) a carrier, which has no sharp edge corner, or has a low true specific gravity.
Claim 2
Dependent Claim
106 words
A developer for developing electrostatic latent image, which comprises: (1) a capsule toner having an irregular shape and a wrinkled surface as substantially depicted in FIG. 2, in which a core material comprises at least, a solvent of high boiling point and a resin for fixing and a coloring agent, both of which are dissolved in or dispersed in the solvent, wherein the core material is enclosed in a shell material containing a chargeable resin, said capsule toner having a mean particle diameter of from 3 to 25 microns; and (2) a carrier, which has no sharp edge corner, or has a low true specific gravity.
Claim 3
Dependent Claim
23 words
A developer of claim 1, in which the shell of toner is made from isocyanates and at least one of polyols and polyamines.
Claim 4
Dependent Claim
21 words
A developer of claim 1, in which the shell of the capsule toner has a thickness of from 0.01 0.8 micron.
Claim 5
Dependent Claim
31 words
A developer of claim 1, in which the solvent contained in the capsule toner is an aliphatic hydrocarbon which may have at least one of a branch and an organic polysiloxane.
Claim 6
Dependent Claim
25 words
A developer of claim 1, in which the solvent contained in the capsule toner has a boiling point of from 150° C. to 350° C.
Claim 7
Dependent Claim
22 words
A developer of claim 1, in which the core material in the toner additionally contains a solvent having a lower boiling point.
Claim 8
Dependent Claim
40 words
A developer of claim 1, in which the resin in the toner is derived from the polymerization of one or more of the monomers selected from the group consisting of acrylic acid esters, methacrylic acid esters, styrene and vinyl monomers.
Claim 9
Dependent Claim
12 words
A developer of claim 1, in which the carrier is substantially spherical.
Claim 10
Dependent Claim
39 words
A developer of claim 1, in which the capsule toner is contained at 1 to 20% by weight in the case of a non-magnetic toner, or at 20 to 60% by weight in the case of a magnetic toner.
Claim 11
Dependent Claim
60 words
A developer of claim 1, in which the capsule toner has a shape factor (SF1) expressed by the following equation and is within the range shown below: SF1={(maximum length).sup.2 /area}×(pai/4)×100, 120≦SF1≦180 wherein the maximum length is the longest distance between any two points on the circumferential of the particle projection and the area is a projection area of the particle.
Claim 12
Dependent Claim
110 words
A developer for developing electrostatic latent image of the claim 1, in which said capsule toner is formed by a process comprising a step of mixing at least a high boiling point solvent, a first shell forming monomer, a fixing monomer, a polymerization initiator and colorant to make a dispersion; a step of emulsifying the dispersion into fine oil drops in an aqueous medium containing a second shell forming monomer; and a step of forming the shell around the oil drops by means of interfacial polymerization between said first and second shell forming monomers and simultaneously or subsequently polymerizing the fixing monomer in the dispersion by means of in-situ polymerization.
Claim 13
Dependent Claim
29 words
A developer of claim 1, in which the carrier has a mean particle diameter of 80 microns or less and a true specific gravity of from 1.0 to 4.5.
Claim 14
Dependent Claim
59 words
A developer of claim 1, in which the carrier has a shape factor (SF1) expressed by the following equation within the range shown below: SF.sup.1 ={(maximum length).sup.2 /area}×(pai/4)×100, 100 ≦SF1≦170 wherein the maximum length is the longest distance between any two points on the circumferential of the particle projection and the area is a projection area of the particle.
Claim 15
Dependent Claim
51 words
A developer of claim 1, in which the carrier has a shape factor (SF2) expressed by the following equation within the range shown below: SF2={(circumferential length).sup.2 /area}×100/4pai 100 ≦SF2≦140 wherein the circumferential length is a circumferential length of the particle projection and the area is a projection area of the particle.
Claim 16
Dependent Claim
19 words
A developer of claim 14, in which the carrier has a shape factor (SF2) of from 100 to 130.
Claim 17
Dependent Claim
92 words
A developer for developing electrostatic latent image, which comprises: (1) a capsule toner having an irregular shape and a wrinkled surface as substantially depicted in FIG. 2, in which a core material comprises a resin for fixing a coloring agent, wherein the core material is enclosed in a shell material containing a chargeable resin, said capsule toner having a mean particle diameter of from 3 to 25 microns; and (2) a carrier having at least one of a no sharp edge corner and a true specific gravity of from 1.0 to 4.5.
Claim 18
Dependent Claim
92 words
A developer for developing electrostatic latent image, which comprises: (1) a capsule toner having an irregular shape and a wrinkled surface as substantially depicted in FIG. 2, in which a core material comprises a resin for fixing a coloring agent, wherein the core material is enclosed in a shell material containing a chargeable resin, said capsule toner having a mean particle diameter of from 3 to 25 microns; and (2) a carrier having at least one of a no sharp edge corner and a true specific gravity of from 1.0 to 4.5.
Claim 19
Dependent Claim
34 words
A developer of claim 16, in which said toner is mixed with an insulating fine particle for preventing adhesion between the toner and the carrier, said insulating fine particle selected from silica and alumina.
Claim 20
Dependent Claim
51 words
A developer for developing electrostatic latent image, which comprises a toner having an irregular shape and a wrinkled surface as substantially depicted in FIG. 2, in which the toner comprises a resin for fixing and a coloring agent, said toner having a mean particle diameter of from 3 to 25 microns.
Claim 21
Dependent Claim
51 words
A developer for developing electrostatic latent image, which comprises a toner having an irregular shape and a wrinkled surface as substantially depicted in FIG. 2, in which the toner comprises a resin for fixing and a coloring agent, said toner having a mean particle diameter of from 3 to 25 microns.
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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) | 1993-11-26 | 1994-05-28 | 1994-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-26 | 1998-05-28 | 1998-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-26 | 2002-05-28 | 2002-11-27 | $7700.00 | Window Closed / Lapsed |