US5053305A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composition and method for developing electrostatic latent images
Assignee: TDK Corp
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Filing: 1989-09-05
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Granted: 1991-10-01
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Expires: 2009-09-05
Abstract
Abstract A composition for developing electrostatic latent images in electrographic printing or copying machinery is provided in which a toner component is blended with 10 to 40% by weight of a carrier. The toner component includes magnetic toner particles each having magnetic powder bound in a resin, and magnetic particles in admixture with the magnetic toner particles, preferably as an external additive in an amount of 0.1 to 10% by weight.
Inventors
- 👤 Kazuo Aoki
- 👤 Akira Kakinuma
- 👤 Megumi Saito
- 👤 Motohiko Makino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:50
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/083; G03G9/0819; G03G9/0831; G03G9/10
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
106 words
An electrostatic latent image developing composition, comprising: (A) a toner component comprising magnetic toner particles having a mean particle diameter of from 5 to 25 μm and each formed from magnetic powder and a resin, and externally added magnetic particles having a mean particle diameter of from 0.01 to 10 μm in an amount of 0.1 to 10% by wt of the magnetic toner particles, which are in admixture with the magnetic toner particles; and (B) from 10 to 40% by wt, based on the weight of the composition of soft magnetic carrier particles which have a mean particle diameter of from 10 to 45 μm.
Claim 2
Dependent Claim
106 words
An electrostatic latent image developing composition, comprising: (A) a toner component comprising magnetic toner particles having a mean particle diameter of from 5 to 25 μm and each formed from magnetic powder and a resin, and externally added magnetic particles having a mean particle diameter of from 0.01 to 10 μm in an amount of 0.1 to 10% by wt of the magnetic toner particles, which are in admixture with the magnetic toner particles; and (B) from 10 to 40% by wt, based on the weight of the composition of soft magnetic carrier particles which have a mean particle diameter of from 10 to 45 μm.
Claim 3
Dependent Claim
20 words
The developing composition of claim 1 wherein said magnetic toner particles each comprise at least two types of magnetic powder.
Claim 4
Dependent Claim
87 words
A method for developing an electrostatic latent image using a developing unit including a magnet, a developing sleeve mounted for relative rotation on the magnet, and a photoconductor disposed in proximity to the sleeve and adapted to have a latent image born thereon, comprising the steps of: charging the developing unit with an electrostatic latent image developing composition as set forth in claim 1, and causing relative rotation of the magnet and the developing sleeve, thereby developing the latent image on the photoconductor with the developing composition.
Claim 5
Dependent Claim
13 words
The method of claim 3 which further includes replenishing only the toner component.
Claim 6
Dependent Claim
16 words
The developing composition of claim 1, wherein toner component (A) further contains a non-magnetic external additive.
Claim 7
Dependent Claim
19 words
The developing composition of claim 5, wherein the external additive has a particle size of 0.01 to 5 μm.
Claim 8
Dependent Claim
28 words
The developing composition of claim 5 or 6, wherein the external additive is present in an amount of 0.1 to 5% by weight based on the toner component.
Claim 9
Dependent Claim
126 words
An electrostatic latent image developing composition, comprising: (A) a toner composition comprising magnetic toner particles having a mean particle diameter of from 5 to 25 μm and each formed from magnetic powder and a resin, and externally added magnetic particles having a mean particle diameter of from 0.01 to 10 μm in an amount of 0.1 to 10% by wt of the magnetic toner particles and 0.1 to 5% by wt of externally added non-magnetic particles having a particle size of 0.01 to 5 μm, which are in admixture with the magnetic toner particles; and (B) from 10 to 40% by wt, based on the weight of the composition, of soft magnetic carrier particles which have a mean particle diameter of from 10 to 45 μm.
Claim 10
Dependent Claim
126 words
An electrostatic latent image developing composition, comprising: (A) a toner composition comprising magnetic toner particles having a mean particle diameter of from 5 to 25 μm and each formed from magnetic powder and a resin, and externally added magnetic particles having a mean particle diameter of from 0.01 to 10 μm in an amount of 0.1 to 10% by wt of the magnetic toner particles and 0.1 to 5% by wt of externally added non-magnetic particles having a particle size of 0.01 to 5 μm, which are in admixture with the magnetic toner particles; and (B) from 10 to 40% by wt, based on the weight of the composition, of soft magnetic carrier particles which have a mean particle diameter of from 10 to 45 μm.
References Cited (Backward Citations)
US3345294A
Cited
JPS5548754A
Cited
JPS5745557A
Cited
JPS5745556A
Cited
JPS5745555A
Cited
JPS59121054A
Cited
JPS59162563A
Cited
US4640880A
Cited
JPS59182464A
Cited
JPS59210450A
Cited
JPS59210466A
Cited
JPS59216149A
Cited
JPS6242163A
Cited
US4797344A
Cited
JPS62275280A
Cited
JPS62294259A
Cited
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| 3.5 Years (Year 4) | 1994-09-30 | 1995-04-01 | 1995-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-30 | 1999-04-01 | 1999-10-01 | $3760.00 | Window Closed / Lapsed |
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