Patent US4038355A successfully refreshed from Google Patents.
Patent EP0331426A2 successfully refreshed from Google Patents.
EP0331426A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Image forming method and image forming apparatus
Assignee: Canon Inc
•
Filing: 1989-02-28
•
Granted: —
•
Expires: 2009-02-28
Abstract
Abstract An image forming apparatus, comprises: an electrostatic image-bearing member for holding an electrostatic latent image; a developing means for developing the electrostatic latent image to form a toner image on the electrostatic image-bearing member, the developing means including a non-magnetic color toner developing means for development with a developer comprising a non-magnetic color toner and a magnetic toner developing means for development with a magnetic toner, wherein the non-magnetic toner has a volume-average particle size of 4 to 15 microns, the magnetic toner contains 17 to 60 % by number of magnetic toner particles having a particle size of 5 microns or smaller, 1 - 23 % by number of magnetic toner particles having a particle size of 8.0 - 12.7 microns and 2.0 % by volume or less of magnetic toner particles having a size of 16 microns or larger, and the magnetic toner has a volume-average particle size of 4 - 9 micron and a degree of aggregation of 50 - 95 %; a transfer means for transferring the toner image formed on the electrostatic image-bearing member to a transfer-receiving material; and a cleaning means for blade-cleaning the surface of the electrostatic image-bearing member after the transfer.
Inventors
- 👤 Satoshi Yoshida
- 👤 Toshiaki Nakahara
- 👤 Hirohide Tanikawa
- 👤 Kiichiro Sakashita
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 12:11
CPC Classifications
G; G03; G03G; G03G13/00; G03G13/01; G03G13/013; G03G13/06; G03G13/08; G03G9/00; G03G9/08; G03G9/0819
Claims Analysis
Total Claims: 46
Claim 1
Independent Claim
197 words
An image forming apparatus, comprising: an electrostatic image-bearing member for holding an electrostatic latent image; a developing means for developing the electrostatic latent image to form a toner image on the electrostatic image-bearing member, the developing means including a non-magnetic color toner-developing means for development with a developer comprising a non-magnetic color toner and a magnetic toner-developing means for development with a magnetic toner, wherein the non-magnetic toner has a volume-average particle size of 4 to 15 microns, the magnetic toner contains 17 to 60 % by number of magnetic toner particles having a particle size of 5 microns or smaller, 1 - 23 % by number of magnetic toner particles having a particle size of 8.0 - 12.7 microns and 2.0 % by volume or less of magnetic toner particles having a size of 16 microns or larger, and the magnetic toner has a volume-average particle size of 4 - 9 microns and a degree of aggregation of 50 - 95 %; a transfer means for transferring the toner image formed on the electrostatic image-bearing member to a transfer-receiving material; and a cleaning means for blade-cleaning the surface of the electrostatic image-bearing member after the transfer.
Claim 2
Dependent Claim
197 words
An image forming apparatus, comprising: an electrostatic image-bearing member for holding an electrostatic latent image; a developing means for developing the electrostatic latent image to form a toner image on the electrostatic image-bearing member, the developing means including a non-magnetic color toner-developing means for development with a developer comprising a non-magnetic color toner and a magnetic toner-developing means for development with a magnetic toner, wherein the non-magnetic toner has a volume-average particle size of 4 to 15 microns, the magnetic toner contains 17 to 60 % by number of magnetic toner particles having a particle size of 5 microns or smaller, 1 - 23 % by number of magnetic toner particles having a particle size of 8.0 - 12.7 microns and 2.0 % by volume or less of magnetic toner particles having a size of 16 microns or larger, and the magnetic toner has a volume-average particle size of 4 - 9 microns and a degree of aggregation of 50 - 95 %; a transfer means for transferring the toner image formed on the electrostatic image-bearing member to a transfer-receiving material; and a cleaning means for blade-cleaning the surface of the electrostatic image-bearing member after the transfer.
Claim 3
Dependent Claim
40 words
An image forming apparatus according to Claim 1, wherein the non-magnetic color toner has a volume-average particle size of 5 - 15 microns which is larger than that of the magnetic toner by 1 micron or more than 1 micron.
Claim 4
Dependent Claim
32 words
An image forming apparatus according to Claim 2, wherein the non-magnetic color toner has a volume-average particle size which is larger than that of the magnetic toner by 1 - 8 microns.
Claim 5
Dependent Claim
86 words
An image forming apparatus according to Claim 1, wherein the magnetic toner has a particle size distribution satisfying the following formula: N/V = -0.04N + k, wherein N denotes the value of % by number of magnetic particles having a size of 5 microns or smaller, V denotes the value of % by volume of magnetic particles having a size of 5 microns or smaller, k is a positive number of from 4.5 to 6.5, and the N is a positive number of 17 to 60.
Claim 6
Dependent Claim
32 words
An image forming apparatus according to Claim 4, wherein the magnetic toner contains 25 - 50 % by number of magnetic toner particles having a particle size of 5 microns or smaller.
Claim 7
Dependent Claim
32 words
An image forming apparatus according to Claim 4, wherein the magnetic toner contains 30 - 50 % by number of magnetic toner particles having a particle size of 5 microns or smaller.
Claim 8
Dependent Claim
21 words
An image forming apparatus according to Claim 4, wherein the magnetic toner satisfies the formula wherein k is 4.5 to 6.0.
Claim 9
Dependent Claim
21 words
An image forming apparatus according to Claim 4, wherein the magnetic toner satisfies the formula wherein k is 4.5 to 5.5.
Claim 10
Dependent Claim
31 words
An image forming apparatus according to Claim 1, wherein the magnetic toner contains 1.0 % by volume or less of magnetic toner particles having a size of 16 microns or larger.
Claim 11
Dependent Claim
31 words
An image forming apparatus according to Claim 1, wherein the magnetic toner contains 0.5 % by volume or less of magnetic toner particles having a size of 16 microns or larger.
Claim 12
Dependent Claim
22 words
An image forming apparatus according to Claim 1, wherein the magnetic toner has a volume-average particle size of 4 - 8 microns.
Claim 13
Dependent Claim
22 words
An image forming apparatus according to Claim 1, wherein the magnetic toner has a degree of aggregation of 50 - 90 %.
Claim 14
Dependent Claim
22 words
An image forming apparatus according to Claim 1, wherein the magnetic toner has a degree of aggregation of 50 - 80 %.
Claim 15
Dependent Claim
21 words
An image forming apparatus according to Claim 1, wherein the magnetic toner has a true density of 1.45 - 1.70 g/cm³.
Claim 16
Dependent Claim
21 words
An image forming apparatus according to Claim 1, wherein the magnetic toner has a true density of 1.50 - 1.65 g./cm³.
Claim 17
Dependent Claim
43 words
An image forming apparatus according to Claim 1, wherein the magnetic toner has a remanence σ r of 1 - 5 emu/g, a saturation magnetization σ s of 20 - 40 emu/g and a coercive force H c of 400 - 100 Oersted.
Claim 18
Dependent Claim
20 words
An image forming apparatus according to Claim 1, wherein the cleaning means comprises a cleaning blade and a cleaning roller.
Claim 19
Dependent Claim
20 words
An image forming apparatus according to Claim 17, wherein the cleaning roller comprises a surface layer of an elastic material.
Claim 20
Dependent Claim
23 words
An image forming apparatus according to Claim 18, wherein the cleaning roller comprises an elastic surface layer of urethane rubber or silicone rubber.
Claim 21
Dependent Claim
24 words
An image forming apparatus according to Claim 17, wherein the cleaning roller comprises a magnetic roller carrying a magnetic toner on the surface thereof.
Claim 22
Dependent Claim
20 words
An image forming apparatus according to Claim 1, wherein the cleaning means comprises a cleaning blades of an elastic material.
Claim 23
Dependent Claim
20 words
An image forming apparatus according to Claim 21, wherein the cleaning blade is formed from urethane rubber or silicone rubber.
Claim 24
Dependent Claim
52 words
An image forming apparatus according to Claim 21, wherein the cleaning blade has a thickness of 0.5 - 4 mm and a rubber hardness (JIS-A) of 50 - 90 degrees, and the cleaning blade is pushed against the surface of the electrostatic image-bearing member at a pressure of 5 - 40 g/cm.
Claim 25
Dependent Claim
54 words
An image forming apparatus according to Claim 17, wherein the cleaning roller comprises a surface layer of urethane rubber of silicone rubber having a rubber hardness (JIS-A) of 50 - 90 degrees and is pressed against the surface of the electrostatic image-bearing member so as to cause a depression of 0.5 - 2 mm.
Claim 26
Dependent Claim
24 words
An image forming apparatus according to Claim 1, wherein the non-magnetic color toner developing means comprises a non-magnetic color toner and a magnetic carrier.
Claim 27
Dependent Claim
33 words
An image forming apparatus according to Claim 1, wherein the non-magnetic color toner and the magnetic toner comprise a binder resin, and the binder resin comprises a vinyl polymer or a polyester resin.
Claim 28
Dependent Claim
16 words
An image forming apparatus according to Claim 26, wherein the binder resin comprises a styrene copolymer.
Claim 29
Dependent Claim
27 words
An image forming apparatus according to Claim 7, wherein the binder resin comprises a styrene-acrylic acid ester copolymer, a styrene-methacrylic acid ester copolymer or a mixture thereof.
Claim 30
Dependent Claim
28 words
An image forming apparatus according to Claim 1, wherein the non-magnetic color toner and the magnetic toner comprise a binder resin, a charge controller and a waxy substance.
Claim 31
Dependent Claim
32 words
An image forming apparatus according to Claim 29, wherein the non-magnetic toner and the magnetic toner contains a nigrosine compound or an organic quaternary ammonium salt and has a positive triboelectric chargeability.
Claim 32
Dependent Claim
25 words
An image forming apparatus according to Claim 30, wherein the non-magnetic toner and the magnetic toner are respectively mixed with silica fine powder externally added.
Claim 33
Dependent Claim
27 words
An image forming apparatus according to Claim 29, wherein the non-magnetic toner and the magnetic toner contains an organic metal complex and has a negative triboelectric chargeability.
Claim 34
Dependent Claim
35 words
An image forming apparatus according to Claim 1, wherein the non-magnetic color toner developing means and the magnetic toner developing means respectively comprise an alternating electric field application means for causing the toner to jump.
Claim 35
Dependent Claim
18 words
An image forming apparatus according to Claim 1, wherein the electrostatic image-bearing member comprises an organic photo-conductive layer.
Claim 36
Dependent Claim
215 words
An image forming method, comprising: developing an electrostatic latent image on an electrostatic image-bearing member with a developer comprising a non-magnetic color toner having a volume-average particle size of 4 to 15 microns to form a non-magnetic color toner image; transferring the non-magnetic color toner image on the electrostatic image-bearing member to a transfer-receiving material; cleaning the electrostatic image-bearing member after the transfer with a cleaning blade; forming an electrostatic image on the electrostatic image-bearing member after the cleaning; developing the electrostatic latent image on the electrostatic image-bearing member with a developer comprising a magnetic toner to form a magnetic toner image, wherein the magnetic toner contains 17 to 60 % by number of magnetic toner particles having a particle size of 5 microns or smaller, 1 - 23 % by number of magnetic toner particles having a particle size of 8.0 - 12.7 microns and 2.0 % by volume or less of magnetic toner particles having a size of 16 microns or larger, and the magnetic toner has a volume-average particle size of 4 - 9 microns and a degree of aggregation of 50 - 95 %; transferring the magnetic toner image on the electrostatic image-bearing member to the transfer-receiving material; and cleaning the electrostatic image-bearing member after the transfer with a cleaning blade.
Claim 37
Dependent Claim
215 words
An image forming method, comprising: developing an electrostatic latent image on an electrostatic image-bearing member with a developer comprising a non-magnetic color toner having a volume-average particle size of 4 to 15 microns to form a non-magnetic color toner image; transferring the non-magnetic color toner image on the electrostatic image-bearing member to a transfer-receiving material; cleaning the electrostatic image-bearing member after the transfer with a cleaning blade; forming an electrostatic image on the electrostatic image-bearing member after the cleaning; developing the electrostatic latent image on the electrostatic image-bearing member with a developer comprising a magnetic toner to form a magnetic toner image, wherein the magnetic toner contains 17 to 60 % by number of magnetic toner particles having a particle size of 5 microns or smaller, 1 - 23 % by number of magnetic toner particles having a particle size of 8.0 - 12.7 microns and 2.0 % by volume or less of magnetic toner particles having a size of 16 microns or larger, and the magnetic toner has a volume-average particle size of 4 - 9 microns and a degree of aggregation of 50 - 95 %; transferring the magnetic toner image on the electrostatic image-bearing member to the transfer-receiving material; and cleaning the electrostatic image-bearing member after the transfer with a cleaning blade.
Claim 38
Dependent Claim
215 words
An image forming method, comprising: developing an electrostatic latent image on an electrostatic image-bearing member with a developer comprising a magnetic toner to form a magnetic toner image, wherein the magnetic toner contains 17 to 60 % by number of magnetic toner particles having a particle size of 5 microns or smaller, 1 - 23 % by number of magnetic toner particles having a particle size of 8.0 - 12.7 microns and 2.0 % by volume or less of magnetic toner particles having a size of 16 microns or larger, and the magnetic toner has a volume-average particle size of 4 - 9 microns and a degree of aggregation of 50 - 95 %; transferring the magnetic toner image on the electrostatic image-bearing member to a transfer-receiving material; cleaning the electrostatic image-bearing member after the transfer with a cleaning blade; forming an electrostatic image on the electrostatic image-bearing member after the cleaning; developing the electrostatic latent image on the electrostatic image-bearing member with a developer comprising a non-magnetic color toner having a volume-average particle size of 4 to 15 microns to form a non-magnetic color toner image; transferring the non-magnetic color toner image on the electrostatic image-bearing member to the transfer-receiving material; and cleaning the electrostatic image-bearing member after the transfer with a cleaning blade.
Claim 39
Dependent Claim
215 words
An image forming method, comprising: developing an electrostatic latent image on an electrostatic image-bearing member with a developer comprising a magnetic toner to form a magnetic toner image, wherein the magnetic toner contains 17 to 60 % by number of magnetic toner particles having a particle size of 5 microns or smaller, 1 - 23 % by number of magnetic toner particles having a particle size of 8.0 - 12.7 microns and 2.0 % by volume or less of magnetic toner particles having a size of 16 microns or larger, and the magnetic toner has a volume-average particle size of 4 - 9 microns and a degree of aggregation of 50 - 95 %; transferring the magnetic toner image on the electrostatic image-bearing member to a transfer-receiving material; cleaning the electrostatic image-bearing member after the transfer with a cleaning blade; forming an electrostatic image on the electrostatic image-bearing member after the cleaning; developing the electrostatic latent image on the electrostatic image-bearing member with a developer comprising a non-magnetic color toner having a volume-average particle size of 4 to 15 microns to form a non-magnetic color toner image; transferring the non-magnetic color toner image on the electrostatic image-bearing member to the transfer-receiving material; and cleaning the electrostatic image-bearing member after the transfer with a cleaning blade.
Claim 40
Dependent Claim
59 words
A method according to Claim 35 or 36, wherein the toner has the features of any of Claims 2 to 11, and/or 26 to 32, cleaning means according to any of claims 17 to 24 is present, non-magnetic colour toner developing means according to Claim 25 is present, or the apparatus has the features of Claims 33 to 34.
Claim 41
Dependent Claim
92 words
A non-magnetic toner that (a) has a volume-average particle size of 4 to 15 microns; (b) contains 17 to 60% by number of magnetic toner particles of 5 microns or below; (c) contains 1 to 23% by number of magnetic toner particles of particle size of 8.0 to 12.7 microns; (d) contains 2.0% by volume or less of magnetic toner particles having a size of 16 microns or above; (e) has a volume average particle size of 4 to 9 microns; and/or (f) has a degree of aggregation of 50 to 95%.
Claim 42
Dependent Claim
92 words
A non-magnetic toner that (a) has a volume-average particle size of 4 to 15 microns; (b) contains 17 to 60% by number of magnetic toner particles of 5 microns or below; (c) contains 1 to 23% by number of magnetic toner particles of particle size of 8.0 to 12.7 microns; (d) contains 2.0% by volume or less of magnetic toner particles having a size of 16 microns or above; (e) has a volume average particle size of 4 to 9 microns; and/or (f) has a degree of aggregation of 50 to 95%.
Claim 43
Dependent Claim
77 words
A magnetic toner having a particle size distribution satisfying the following formula: N/V = -0.04N + k, wherein N denotes the value of % by number of magnetic particles having a size of 5 microns or smaller, V denotes the value of % by volume of magnetic particles having a size of 5 microns or smaller, k is a positive number of from 4.5 to 6.5, and the N is a positive number of 17 or 60.
Claim 44
Dependent Claim
77 words
A magnetic toner having a particle size distribution satisfying the following formula: N/V = -0.04N + k, wherein N denotes the value of % by number of magnetic particles having a size of 5 microns or smaller, V denotes the value of % by volume of magnetic particles having a size of 5 microns or smaller, k is a positive number of from 4.5 to 6.5, and the N is a positive number of 17 or 60.
Claim 45
Dependent Claim
26 words
A method of developing an electrostatic latent image to form a toner image which comprises applying thereto a toner as defined in Claim 38 to 39.
Claim 46
Dependent Claim
29 words
A method of removing toner from an electrostatic image-bearing member developed with a toner as claimed in Claim 38 or 39 comprising cleaning the member with a cleaning blade.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.