US4530893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
One-component type red color magnetic developer
Assignee: Kyocera Mita Industrial Co Ltd
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Filing: 1983-11-29
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Granted: 1985-07-23
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Expires: 2003-11-29
Abstract
Abstract Disclosed is a one-component type red color magnetic developer having a self-electroscopic property, which comprises particles prepared from a kneaded composition comprising 100 parts by weight of a magnetic powder composed mainly of ocherous gamma-type diiron trioxide, 2.5 to 30 parts by weight of a red azo pigment and 40 to 200 parts by weight of a binder resin, wherein a fixed image of the particles is measured by a color difference meter, the value x is from 0.51 to 0.73, the value y is from 0.22 to 0.40 and the value Y is from 5 to 65%.
Inventors
- 👤 Kouji Maekawa
- 👤 Nobuhiro Miyakawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:36
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/083; G03G9/0831; G03G9/0833; G03G9/09; G03G9/0906; G03G9/091; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/104
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
109 words
A one-component type red color magnetic developer having a self-electroscopic property, which comprises particles prepared by pulverizing a kneaded composition comprising 100 parts by weight of a magnetic powder composed mainly of ocherous gamma-type diiron trioxide having a number average particle size of 0.2 to 2 microns, 10 to 20 parts by weight of a red azo pigment and 40 to 200 parts by weight of a binder resin, wherein when a fixed image of the particles is measured by a color difference meter, the value x is from 0.51 to 0.73, the value y is from 0.22 to 0.40 and the value Y is from 5 to 65%.
Claim 2
Dependent Claim
109 words
A one-component type red color magnetic developer having a self-electroscopic property, which comprises particles prepared by pulverizing a kneaded composition comprising 100 parts by weight of a magnetic powder composed mainly of ocherous gamma-type diiron trioxide having a number average particle size of 0.2 to 2 microns, 10 to 20 parts by weight of a red azo pigment and 40 to 200 parts by weight of a binder resin, wherein when a fixed image of the particles is measured by a color difference meter, the value x is from 0.51 to 0.73, the value y is from 0.22 to 0.40 and the value Y is from 5 to 65%.
Claim 3
Dependent Claim
79 words
A magnetic developer as set forth in claim 1, wherein the red azo pigment is selected from Pigment Red 1 (C.I. 12070), Pigment Red 2 (C.I. 12310), Pigment Red 3 (C.I. 12120), Pigment Red 5 (C.I. 12490), Pigment Red 7 (C.I. 12420), Pigment Red 11 (C.I. 12430), Pigment Red 12 (C.I. 12385), Pigment Red 13 (C.I. 12395), Pigment Red 14 (C.I. 12380), Pigment Red 48 (C.I. 15865), Pigment Red 49 (C.I. 15630) and Pigment Red 60 (C.I. 16015 Lake).
Claim 4
Dependent Claim
27 words
A magnetic developer as set forth in claim 1, wherein the binder resin is a homopolymer or copolymer of a vinyl aromatic monomer or an acrylic monomer.
Claim 5
Dependent Claim
27 words
A magnetic developer as set forth in claim 3, wherein the vinyl aromatic monomer is selected from styrene, vinyl toluene, α-methylstyrene, α-chlorostyrene, vinyl xylene and vinyl naphthalene.
Claim 6
Dependent Claim
42 words
A magnetic developer as set forth in claim 3, wherein the acrylic monomer is selected from acrylic acid, methacrylic acid, ethyl acrylate, methyl methacrylic, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 3-aminopropyl acrylate, 3-N,N-diethylaminopropyl acrylate and acrylamide.
Claim 7
Dependent Claim
21 words
A magnetic developer as set forth in claim 1, wherein the binder resin has a molecular weight of 3,000 to 300,000.
Claim 8
Dependent Claim
32 words
A magnetic developer as set forth in claim 1, wherein the amount of the binder resin is 60 to 160 parts by weight per 100 parts by weight of the magnetic powder.
Claim 9
Dependent Claim
32 words
A magnetic developer as set forth in claim 1 wherein the amount of the red azo pigment is about 10 parts by weight per 100 parts by weight of the magnetic powder.
Claim 10
Dependent Claim
35 words
A magnetic developer as set forth in claim 1 wherein the value x is from 0.58 to 0.65, the value y is from 0.28 to 0.30, and the value Y is from 8.8 to 10.8%.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |