US4933253A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic developer comprising toner particles and acrylic polymer fine particles
Assignee: Fujifilm Business Innovation Corp
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Filing: 1985-03-06
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Granted: 1990-06-12
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Expires: 2005-03-06
Abstract
Abstract A developer for an electrostatic latent image is disclosed, which comprises a toner powder and a fine powder of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder. The developer can be easily cleaned off without causing damage to a latent image-forming member.
Inventors
- 👤 Takayoshi Aoki
- 👤 Yukihiro Ishii
- 👤 Koichi Tanaka
- 👤 Shigeru Sadamatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:38
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/0819; G03G9/0825; G03G9/0827; G03G9/087; G03G9/08702; G03G9/08706; G03G9/08708; G03G9/08711; G03G9/09; G03G9/0902; G03G9/097; G03G9/09708; G03G9/09716; G03G9/09725; G03G9/10; G03G9/113; G03G9/1132; G03G9/1133; G03G9/1139
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
54 words
A developer for use in electrophotography consisting essentially of a toner powder which contains a colorant and 0.01 to 10 wt % based on the wt % of the toner of a fine powder consisting essentially of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder.
Claim 2
Dependent Claim
54 words
A developer for use in electrophotography consisting essentially of a toner powder which contains a colorant and 0.01 to 10 wt % based on the wt % of the toner of a fine powder consisting essentially of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder.
Claim 3
Dependent Claim
56 words
A developer for use in electrophotography consisting essentially of carrier particles, a toner powder which contains a colorant and 0.01 to 10 wt % based on the wt % of the toner of a fine powder consisting essentially of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder.
Claim 4
Dependent Claim
56 words
A developer for use in electrophotography consisting essentially of carrier particles, a toner powder which contains a colorant and 0.01 to 10 wt % based on the wt % of the toner of a fine powder consisting essentially of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder.
Claim 5
Dependent Claim
22 words
A developer according to claim 1 or 2, wherein said fine powder comprises particles ranging from 0.05 to 5 μm in size.
Claim 6
Dependent Claim
22 words
A developer according to claim 1 or 2, wherein said fine powder comprises particles ranging from 0.1 to 2 μm in size.
Claim 7
Dependent Claim
16 words
A developer according to claim 1 or 2, wherein said fine powder comprises substantially spherical particles.
Claim 8
Dependent Claim
25 words
A developer according to claim 1 or 2, wherein said acrylic homopolymer or copolymer contains an acrylic or methacrylic acid ester as a monomer component.
Claim 9
Dependent Claim
25 words
A developer according to claim 1 or 2, wherein said acrylic homopolymer or copolymer has a weight average molecular weight of from 10,000 to 300,000.
Claim 10
Dependent Claim
20 words
A developer according to claim 2, wherein said carrier particles each consists of a core material and a surface coat.
Claim 11
Dependent Claim
33 words
A developer according to claim 8, wherein the surface coat on each carrier particle is made of at least one resin selected from the group consisting of fluoroplastics, acrylic resins and silicone resins.
Claim 12
Dependent Claim
31 words
A developer according to claim 8, wherein the surface coat on each carrier particle is made of an acrylic resin containing an acrylic or methacrylic acid ester as a monomer component.
Claim 13
Dependent Claim
28 words
A developer according to claim 8, wherein the surface coat on each carrier particle is made of a silicone resin containing a siloxane bond in the main chain.
Claim 14
Dependent Claim
39 words
A developer according to claim 8, wherein the surface coat on each carrier particle is made of a silicone resin selected from the group consisting of polymethyl siloxane, polymethylphenyl siloxane, polyphenyl siloxane, acryl-modified silicone resin and epoxy-modified silicone resin.
Claim 15
Dependent Claim
50 words
A developer according to claim 1 or 2, wherein said developer contains a colorant selected from the group consisting of carbon black, Nigrosine dyes, Aniline Blue, Alcohoil Blue, Chrome Yellow, Ultramarine Blue, Dupont Oil Red, Quinoline Yellow, Methylene Blue Chloride, Phthalocyanine Blue, Malachite Green oxalate, Lamp Black and Rose Bengal.
Claim 16
Dependent Claim
22 words
A developer according to claim 1 or 2, wherein said toner powder has an average particle size of 3 to 20 μm.
Claim 17
Dependent Claim
18 words
A developer according to claims 1 or 2, consisting essentially of said toner powder and said fine powder.
Claim 18
Dependent Claim
17 words
A developer accordingly to claims 1 or 2, consisting of said toner powder and said fine powder.
Claim 19
Dependent Claim
53 words
A developer for use in electrophotography consisting essentially of a toner powder which contains a colorant and 0.01 to 10 wt % based on the wt % of the toner of a fine powder consisting of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder.
Claim 20
Dependent Claim
53 words
A developer for use in electrophotography consisting essentially of a toner powder which contains a colorant and 0.01 to 10 wt % based on the wt % of the toner of a fine powder consisting of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder.
Claim 21
Dependent Claim
56 words
A developer for use in electrophotography consisting essentially of carrier particles, a toner powder which contains a colorant and 0.01 to 10 wt % based on the wt % of the toner powder of a fine powder consisting of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder.
Claim 22
Dependent Claim
56 words
A developer for use in electrophotography consisting essentially of carrier particles, a toner powder which contains a colorant and 0.01 to 10 wt % based on the wt % of the toner powder of a fine powder consisting of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder.
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) | 1993-06-11 | 1993-12-11 | 1994-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-11 | 1997-12-11 | 1998-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-11 | 2001-12-11 | 2002-06-12 | $7700.00 | Window Closed / Lapsed |