Patent US5270143A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5270143A Expired / Lapsed US ⏱️ 0.0 years remaining

Developer for developing electrostatic image, image forming method, electrophotographic apparatus, apparatus unit, and facsimile apparatus

Assignee: Canon Inc
•
Filing: 1991-10-28
•
Granted: 1993-12-14
•
Expires: 2011-10-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A developer for developing an electrostatic image has a toner, fine resin particles with a surface shape sphericity ψ of from 0.90 to 0.50, and fine inorganic particles.

Inventors

  • 👤 Koichi Tomiyama
  • 👤 Masayoshi Kato
  • 👤 Tsutomu Kukimoto
  • 👤 Hiroshi Yusa
  • 👤 Kiyoko Tsuchiya

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 06:11
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/0827; G03G9/097

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 28 words
A developed for developing an electrostatic image, comprising a toner, fine resin particles with a surface shape sphericity ψ of from 0.90 to 0.50, and fine inorganic particles.
Claim 2
Dependent Claim 28 words
A developed for developing an electrostatic image, comprising a toner, fine resin particles with a surface shape sphericity ψ of from 0.90 to 0.50, and fine inorganic particles.
Claim 3
Dependent Claim 37 words
The developer according to claim 1, wherein said fine resin particles have an average particle diameter smaller than the average particle diameter of said toner and larger than the average particle diameter of said fine inorganic powder.
Claim 4
Dependent Claim 24 words
The developer according to claim 1, wherein said fine resin particles have a primary average particle diameter of from 0.03 μ to 1.0 μ.
Claim 5
Dependent Claim 24 words
The developer according to claim 1, wherein said fine resin particles have a primary average particle diameter of from 0.05 μ to 0.8 μ.
Claim 6
Dependent Claim 23 words
The developer according to claim 1, wherein said fine resin particles have a triboelectric charge quantity of from -200 μc/g to +50 μc/g.
Claim 7
Dependent Claim 23 words
The developer according to claim 1, wherein said fine resin particles have a triboelectric charge quantity of from -100 μc/g to +30 μc/g.
Claim 8
Dependent Claim 24 words
The developer according to claim 1, wherein said fine resin particles have a specific resistance of from 10 6 Ω.cm to 10 13 Ω.cm.
Claim 9
Dependent Claim 15 words
The developer according to claim 1, wherein said fine resin particles comprise a styrene resin.
Claim 10
Dependent Claim 22 words
The developer according to claim 1, wherein said fine resin particles have not less than 51% by weight of styrene monomer units.
Claim 11
Dependent Claim 21 words
The developer according to claim 1, wherein said fine resin particles have a glass transition point of 80° C. or above.
Claim 12
Dependent Claim 80 words
The developer according to claim 1, wherein said toner has a weight average particle diameter of from 3.5 μm to 20 μm, said fine resin particles have a primary average particle diameter of from 0.03 μ to 1.0 μ, and said fine inorganic powder has a primary average particle diameter of from 0.002 μ to 0.2 μ; the primary average particle diameter of said fine inorganic powder being smaller than the primary average particle diameter of said fine resin particles.
Claim 13
Dependent Claim 22 words
The developer according to claim 11, wherein said toner has a weight average particle diameter of from 3.5 μm to 14 μm.
Claim 14
Dependent Claim 22 words
The developer according to claim 11, wherein said toner has a weight average particle diameter of from 4 μm to 8 μm.
Claim 15
Dependent Claim 17 words
The developer according to claim 13, wherein said toner comprises toner particles containing a charge control agent.
Claim 16
Dependent Claim 101 words
The developer according to claim 1, wherein said toner comprises toner particles containing a negative charge control agent represented by the following Formula (I). ##STR4## wherein M represents Cr, Co, Ni, Mn or Fe having the coordination number or 6; Ar represents an aryl group which may have a substituent; X, X', Y and Y' may be the same or different and each represent --O--, --CO--, --NH-- or --NR--, where R represents an alkyl group having 1 to 4 carbon atoms; and A⊕ represents a hydrogen ion, a sodium ion, a potassium ion, an ammonium ion or an aliphatic ammonium ion.
Claim 17
Dependent Claim 36 words
The developer according to claim 1, wherein said toner comprises toner particles containing a wax having a ratio (Mw/Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn) of not less than 5.
Claim 18
Dependent Claim 37 words
The developer according to claim 1, wherein said toner comprises toner particles having a binder resin containing not less than 15% of a component with a molecular weight of not more than 5,000 in a GPC chromatogram.
Claim 19
Dependent Claim 37 words
The developer according to claim 1, wherein said toner comprises toner particles having a binder resin containing from 15% to 35% of a component with a molecular weight of not more than 5,000 in a GPC chromatogram.
Claim 20
Dependent Claim 13 words
The developer according to claim 1, wherein said toner comprises magnetic tone particles.
Claim 21
Dependent Claim 19 words
The developer according to claim 1, wherein said toner comprises insulating magnetic toner particles having a negative triboelectric chargeability.
Claim 22
Dependent Claim 28 words
The developer according to claim 18, wherein said toner comprises toner particles having a binder resin comprising a styrene polymer, a styrene copolymer, or a mixture of these.
Claim 23
Independent Claim 111 words
A method or forming an image by a process comprising the steps of; bringing a charging member to which a voltage has been externally applied, into contact with an electrostatic image bearing member to effect electrostatic charging; forming an electrostatic image on the charged electrostatic image bearing member; developing the electrostatic image formed on said electrostatic image bearing member, using a developer to form a toner image; said developer comprising a toner, fine resin particles with a surface shape sphericity ψ of from 0.90 to 0.50, and fine inorganic particles; and transferring the toner image formed on said electrostatic image bearing member to a transfer medium to form a transferred image.
Claim 24
Independent Claim 111 words
A method or forming an image by a process comprising the steps of; bringing a charging member to which a voltage has been externally applied, into contact with an electrostatic image bearing member to effect electrostatic charging; forming an electrostatic image on the charged electrostatic image bearing member; developing the electrostatic image formed on said electrostatic image bearing member, using a developer to form a toner image; said developer comprising a toner, fine resin particles with a surface shape sphericity ψ of from 0.90 to 0.50, and fine inorganic particles; and transferring the toner image formed on said electrostatic image bearing member to a transfer medium to form a transferred image.
Claim 25
Dependent Claim 59 words
The image forming method according to claim 22, wherein said electrostatic image bearing member has an OPC photosensitive member and is negatively charged by means of a charging member; an electrostatic image having a negative charge is formed on said electrostatic image bearing member; and said electrostatic image is reversely developed by the toner having a negative triboelectric charge.
Claim 26
Dependent Claim 19 words
The image forming method according to claim 22, wherein a direct current voltage is applied to said charging member.
Claim 27
Dependent Claim 19 words
The image forming method according to claim 22, wherein an alternating current voltage is applied to said charging member.
Claim 28
Dependent Claim 25 words
The image forming method according to claim 22, wherein a direct current voltage overlaid with an alternating current voltage is applied to said charging member.
Claim 29
Dependent Claim 24 words
The image forming method according to claim 22, wherein said electrostatic image bearing member is cleaned by a cleaning blade after the transfer step.
Claim 30
Dependent Claim 46 words
The image forming method according to claim 27, wherein part of the fine resin particles contained in the developer is not cleaned by said cleaning blade but transferred to the charging member, so that said fine resin particles adhere to the surface of said charging member.
Claim 31
Dependent Claim 61 words
The image forming method according to claim 22, wherein said charging member is brought into contact with said electrostatic image bearing member at a contact pressure of from 5 g/cm to 500 g/cm, and from -200 V to -900 V of direct current voltage and from 0.5 kVpp to 5 kVpp of alternating current voltage are applied to said charging member.
Claim 32
Dependent Claim 25 words
The image forming method according to claim 29, wherein said alternating current voltage has an alternating current frequency of from 50 Hz to 3,000 Hz.
Claim 33
Dependent Claim 31 words
The image forming method according to claim 22, wherein said charging member is roller-shaped, has a release film surface layer, and electrostatically charges the electrostatic image bearing member while being rotated.
Claim 34
Dependent Claim 26 words
The image forming method according to claim 22, wherein the electrostatic image is developed by the developer according to any one of claims 2 to 21.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-12-13 1997-06-14 1997-12-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-12-13 2001-06-14 2001-12-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-12-13 2005-06-14 2005-12-14 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag