Patent EP0070117A2 successfully refreshed from Google Patents.
EP0070117A2
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Magnetic developer
Assignee: Kyocera Mita Industrial Co Ltd
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Filing: 1982-06-28
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Granted: —
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Expires: 2002-06-28
Abstract
Abstract A dry magnetic developer for use in electrophotography consists essentially of particles of a composition comprising a binder resin and a powdery magnetic material dispersed in the binder resin, wherein the magnetic material is composed of non-pulverizing agglomerates having a number average particle size of 1 to 10 microns, and which have been formed by granulating and sintering fine cubic particles of magnetite or another ferrite having a number average particle size of 0.1 to 1 micron.
Inventors
- 👤 Nobuhiro Miyakawa
- 👤 Masanori Nakamozu-Koen Danchi 1-1027 Fujii
- 👤 Kouzi Maekawa
- 👤 Haruo Koyama
- 👤 Takashi Teshima
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 06:53
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/083; G03G9/0836; G03G9/0837; G03G9/0838; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/104
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
78 words
A dry magnetic developer consisting essentially of particles of a composition comprising a binder resin and a powdery magnetic material dispersed in the binder resin, characterised in that the magnetic material is composed of non-pulverizing agglomerates (as hereinbefore defined) having a number average particle size of 1 to 10 microns and which have been formed by granulating and sintering fine cubic particles of magnetite or another ferrite having a number average particle size of 0.1 to 1 micron.
Claim 2
Dependent Claim
78 words
A dry magnetic developer consisting essentially of particles of a composition comprising a binder resin and a powdery magnetic material dispersed in the binder resin, characterised in that the magnetic material is composed of non-pulverizing agglomerates (as hereinbefore defined) having a number average particle size of 1 to 10 microns and which have been formed by granulating and sintering fine cubic particles of magnetite or another ferrite having a number average particle size of 0.1 to 1 micron.
Claim 3
Dependent Claim
28 words
A magnetic developer according to claim 1, wherein the agglomerates have an apparent density of 0.4 to 1.5 g/ml, as measured according to the method of JIS K-5101.
Claim 4
Dependent Claim
31 words
A magnetic developer according to claim 1 or 2, wherein faces of exposed non-pulverizing agglomerates and faces of the binder resin medium are present at the surfaces of the developer particles.
Claim 5
Dependent Claim
36 words
A magnetic developer according to any one of the preceding claims wherein the binder resin has a volume resistivity of at least 1 x 10 -5 Ω-cm, as measured in the absence of the non-pulverizing agglomerates.
Claim 6
Dependent Claim
39 words
A magnetic developer according to any one of the preceding claims wherein the non-pulverizing agglomerates are present in an amount of 40 to 70% by weight, based on the total amount of the binder resin medium and magnetic material.
Claim 7
Dependent Claim
37 words
A magnetic developer according to any one of the preceding claims which has a number average particle size of 5 to 35 pm, which is at least twice the number average particle size of the non-pulverizing agglomerates.
Claim 8
Dependent Claim
23 words
Use of a magnetic developer as claimed in any one of the preceding claims in the development of electrostatic latent images in electrophotography.
References Cited (Backward Citations)
No citation records indexed.
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