US4917952A
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Electroconductive iron oxide particles
Assignee: Toda Kogyo Corp
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Filing: 1988-09-26
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Granted: 1990-04-17
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Expires: 2008-09-26
Abstract
Abstract Disclosed herein are electroconductive iron oxide particles having a volume resistivity less than 5×10 6 Ω-cm, and comprising iron oxide particles selected from hematite and maghemite, and SnO 2 particles containing Sb as a solid solution deposited on the surfaces of the iron oxide particles, and a process for producing the same.
Inventors
- 👤 Tsutomu Katamoto
- 👤 Tokihiro Kurata
- 👤 Nanao Horiishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:42
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/06; H01B1/08; C; C08; C08K; C08K9/00; C08K9/02; C09; C09C; C09C1/00; C09C1/22; C09C1/24; C09C1/245; C01; C01P; C01P2002/00; C01P2002/50; C01P2002/70; C01P2002/72; C01P2004/00; C01P2004/01; C01P2004/03; C01P2004/10; C01P2004/20; C01P2004/30; C01P2004/32; C01P2004/38; C01P2004/54; C01P2004/60; C01P2004/61; C01P2004/62; C01P2004/80; C01P2006/00; C01P2006/40; C01P2006/60; C01P2006/62; C01P2006/66; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/928; Y10S428/9335; Y10S428/937; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2989; Y10T428/2991; Y10T428/2993
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
42 words
Electroconductive iron oxide particles having a volume resistivity less than 5×10 6 Ω-cm, and comprising iron oxide particles selected from hematite and maghemite, and SnO 2 particles containing Sb as a solid solution deposited on the surfaces of the iron oxide particles.
Claim 2
Dependent Claim
42 words
Electroconductive iron oxide particles having a volume resistivity less than 5×10 6 Ω-cm, and comprising iron oxide particles selected from hematite and maghemite, and SnO 2 particles containing Sb as a solid solution deposited on the surfaces of the iron oxide particles.
Claim 3
Dependent Claim
35 words
Electroconductive iron oxide particles according to claim 1, wherein the SnO 2 particle containing Sb as a solid solution is deposited in an amount of 5.0 to 200% by weight based on iron oxide particle.
Claim 4
Dependent Claim
41 words
Electroconductive iron oxide particles according to claim 1, wherein the amount of Sb in the SnO 2 particle containing Sb as a solid solution is 0.1 to 40.0% by weight based on SnO 2 particle containing Sb as a solid solution.
Claim 5
Dependent Claim
18 words
Electroconductive iron oxide particles according to claim 1, wherein the iron oxide particle is a plate-like hematite particle.
Claim 6
Dependent Claim
37 words
Electroconductive iron oxide particles according to claim 4, wherein the plate-like hematite particles have an average diameter of 0.5 to 100 μm, a thickness of 0.005 to 15 μm and an aspect ratio of 2:1 to 500:1.
Claim 7
Dependent Claim
37 words
Electroconductive iron oxide particles according to claim 4, wherein the plate-like hematite particles have an average diameter of 0.5 to 5.0 μm, a thickness of 50 to 500 Å and an aspect ratio of 50:1 to 500:1.
Claim 8
Dependent Claim
31 words
Electroconductive iron oxide particles according to claim 1 wherein the iron oxide particle is coated with a layer of an oxide of Si or Ti or both of Si and Ti.
Claim 9
Dependent Claim
17 words
Electroconductive iron oxide particles according to claim 7 having a volume resistivity less than 5×10 5 Ω-cm.
Claim 10
Dependent Claim
33 words
Electroconductive iron oxide particles according to claim 7, wherein the amount of Si in the coating layer is 1 to 100% by weight (calculated as SiO 2 ) based on iron oxide particle.
Claim 11
Dependent Claim
33 words
Electroconductive iron oxide particles according to claim 7, wherein the amount of Ti in the coating layer is 1 to 100% by weight (calculated as TiO 2 ) based on iron oxide particle.
Claim 12
Dependent Claim
14 words
Electroconductive iron oxide particles according to claim 1, which are plate-like electroconductive hematite particles.
Claim 13
Dependent Claim
38 words
Electroconductive iron oxide particles according to claim 11, wherein the plate-like electroconductive hematite particles have an average diameter of 0.5 to 100 μm, a thickness of 0.005 to 15 μm and an aspect ration of 2:1 to 500:1.
Claim 14
Dependent Claim
38 words
Electroconductive iron oxide particles according to claim 11, wherein the plate-like electroconductive hematite particles have an average diameter of 0.5 to 5.0 μm, a thickness of 50 to 500 Å and an aspect ratio of 50:1 to 500:1.
Claim 15
Dependent Claim
47 words
Electroconductive iron oxide particles according to claim 13, wherein the plate-like electroconductive hematite particles have a lightness of L* of not less than 30, a hue (θ=Tan -1 b * /a * ) of not less than 50° and a saturation C* of not less than 17.
References Cited (Backward Citations)
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