EP0275636A2 — Color toner and two-component developer containin…

Claim 1

Independent Claim 518 words

A process for forming multi-colour images by electrophotography, comprising forming first, second, third and fourth electrostatic latent images (A), (B), (C), and (D) on an image-bearing member, developing the electrostatic latent images (A), (B), (C) and (D) on the image-bearing member with respective developers (A), (B), (C) and (D) each comprising a different colour toner (A), (B), (C) or (D) respectively to form a developed image of the colour toner (A), (B), (C) or (D) on the image-bearing member, transferring the developed images of the colour toners (A), (B), (C) and (D) to a transfer material, and fixing the developed images of the colour toners (A), (B), (C) and (D) to the transfer material to form a multi-colour image on the transfer material, wherein each of the developers (A), (B), (C) and (D) comprises (1) a colour toner composition containing said respective colour toner (A), (B), (C) or (D) which in turn contains at least a binder resin and a colorant, and a fluidity improver, and (2) a ferrite carrier coated with fIuorine-containing resin-styrene type resin, the colour toner composition having an agglomeration degree of 25% or below and an apparent density of 0.2 to 1.5 g/cm³, and the colour toner having a volume-average particle size of 11.0 to 14.0 microns, containing 30% by number or less of particles having sizes below 6.35 microns and containing 9% by weight or less of particles having sizes above 20.2 microns, having an apparent viscosity at 100°C of 10⁴to 5 × 10⁵ poise, an apparent viscosity at 90 °C of 5 × 10 ⁴to 5 × 10⁶ poise, a DSC heat-absorption peak at 58 to 72 °C, and a gloss of 5.0% or higher, and showing a triboelectric charge of -5 to -20 micro-C/g with respect to a ferrite carrier coated with fluorine-containing resin-styrene type resin containing 70 wt.% or more of carrier particles having sizes of 250 mesh-pass and 350 mesh-on, and wherein the developers (A), (B), (C) and (D) are selected from yellow developer, magenta developer, cyan developer and black developer, each developer containing a respective colorant, the yellow toner containing 0.1 to 12.0 wt. parts of the yellow colorant per 100 wt. parts of the binder resin and having chromaticity values of a* = -6.5 to -26.5, b* = 73.0 to 93.0, and L* = 77.0 to 97.0, the magenta toner containing 0.1 to 15.0 wt. parts of the magenta colorant per 100 wt. parts of the binder resin and having chromaticity values of a* = 60.0 to 80.0, b* = -12.0 to -32.0 and L* = 40.0 to 60.0, the cyan toner containing 0.1 to 15.0 wt. parts of the cyan colorant per 100 wt. parts of the binder resin and having chromaticity values of a* = -8 to -28.0, b* -30.0 to -5.0, and L* 39.0 to 59.0, and the black toner containing two or more colorants and showing a reflectance of 40% or higher in the near infrared wavelength region of 900 to 1000 nm, and chromaticity values of a* = -3.5 to +6.5, b* = -6.0 to 4.0, and L* = 26.0 to 36.0.

Claim 2

Dependent Claim 518 words

A process for forming multi-colour images by electrophotography, comprising forming first, second, third and fourth electrostatic latent images (A), (B), (C), and (D) on an image-bearing member, developing the electrostatic latent images (A), (B), (C) and (D) on the image-bearing member with respective developers (A), (B), (C) and (D) each comprising a different colour toner (A), (B), (C) or (D) respectively to form a developed image of the colour toner (A), (B), (C) or (D) on the image-bearing member, transferring the developed images of the colour toners (A), (B), (C) and (D) to a transfer material, and fixing the developed images of the colour toners (A), (B), (C) and (D) to the transfer material to form a multi-colour image on the transfer material, wherein each of the developers (A), (B), (C) and (D) comprises (1) a colour toner composition containing said respective colour toner (A), (B), (C) or (D) which in turn contains at least a binder resin and a colorant, and a fluidity improver, and (2) a ferrite carrier coated with fIuorine-containing resin-styrene type resin, the colour toner composition having an agglomeration degree of 25% or below and an apparent density of 0.2 to 1.5 g/cm³, and the colour toner having a volume-average particle size of 11.0 to 14.0 microns, containing 30% by number or less of particles having sizes below 6.35 microns and containing 9% by weight or less of particles having sizes above 20.2 microns, having an apparent viscosity at 100°C of 10⁴to 5 × 10⁵ poise, an apparent viscosity at 90 °C of 5 × 10 ⁴to 5 × 10⁶ poise, a DSC heat-absorption peak at 58 to 72 °C, and a gloss of 5.0% or higher, and showing a triboelectric charge of -5 to -20 micro-C/g with respect to a ferrite carrier coated with fluorine-containing resin-styrene type resin containing 70 wt.% or more of carrier particles having sizes of 250 mesh-pass and 350 mesh-on, and wherein the developers (A), (B), (C) and (D) are selected from yellow developer, magenta developer, cyan developer and black developer, each developer containing a respective colorant, the yellow toner containing 0.1 to 12.0 wt. parts of the yellow colorant per 100 wt. parts of the binder resin and having chromaticity values of a* = -6.5 to -26.5, b* = 73.0 to 93.0, and L* = 77.0 to 97.0, the magenta toner containing 0.1 to 15.0 wt. parts of the magenta colorant per 100 wt. parts of the binder resin and having chromaticity values of a* = 60.0 to 80.0, b* = -12.0 to -32.0 and L* = 40.0 to 60.0, the cyan toner containing 0.1 to 15.0 wt. parts of the cyan colorant per 100 wt. parts of the binder resin and having chromaticity values of a* = -8 to -28.0, b* -30.0 to -5.0, and L* 39.0 to 59.0, and the black toner containing two or more colorants and showing a reflectance of 40% or higher in the near infrared wavelength region of 900 to 1000 nm, and chromaticity values of a* = -3.5 to +6.5, b* = -6.0 to 4.0, and L* = 26.0 to 36.0.

Claim 3

Dependent Claim 36 words

A process according to claim 1, wherein said developer (A) is the magenta developer, said developer (B) is the cyan developer, said developer (C) is the yellow developer, and said developer (D) is the black developer.

Claim 4

Dependent Claim 17 words

A process according to claim 1 or 2, wherein said fluidity improver comprises hydrophobic silica fine powder.

Claim 5

Dependent Claim 47 words

A process according to claim 1, 2 or 3, wherein the electrostatic latent images (A), (B), (C) and (D) are respectively developed with a toner under the application of a bias electric field between an image bearing member and a developing sleeve carrying one of the developers.

Claim 6

Dependent Claim 15 words

A process according to claim 4, wherein the bias electric field comprises an AC component.

Claim 7

Dependent Claim 28 words

A process according to claim 5, wherein the bias electric field comprises a frequency of 1000 to 3000 Hz and a peak-to-peak voltage of 1000 to 2500 volts.

Claim 8

Dependent Claim 40 words

A process according to any preceding claim, wherein each developer contains 5 to 15 wt. % of the toner based on the developer and 0.01 to 10 wt. parts of the fluidity improver per 100 wt. parts of the toner.

Claim 9

Dependent Claim 22 words

A process according to claim 7, wherein in each developer the carrier has an average particle size of 20 to 100 microns.

Claim 10

Dependent Claim 20 words

A process according to any preceding claim, wherein the carrier occupies 1.5 to 40% by volume in a development region.

Claim 11

Dependent Claim 38 words

A process according to claim 9, wherein the toner is transferred from the surface of the carrier and the surface of a developing sleeve carrying the developer to the image-bearing member to develop the electrostatic latent image thereon.

Claim 12

Dependent Claim 40 words

A process according to any preceding claim, wherein the electrostatic latent images are developed with the developers in the order of the magenta developer, the cyan developer, the yellow developer and the black developer to form developed colour toner images.

Claim 13

Dependent Claim 39 words

A process according to claim 11, wherein the developed toner images are electrostatically transferred to the transfer material in the order of the magenta toner image, the cyan toner image, the yellow toner image and the black toner image.

Claim 14

Dependent Claim 59 words

A process according to claim 12, wherein the electrostatic transfer of the developed cyan toner images are conducted under the applications of transfer currents satisfying the conditions of: transfer current for the magenta toner image < transfer current for the cyan toner image < transfer current for the yellow toner image < transfer current for the black toner image.

Claim 15

Dependent Claim 67 words

A process according to any preceding claim, wherein the yellow toner, magenta toner and cyan toner satisfy angular relationships on their chromaticity diagran that the cyan toner and yellow toner form an angle of 145 ± 15 deg., the cyan toner and magenta toner form an angle of 95 ± 15 deg., and the magenta toner and yellow toner form an angle of 120 ± 10 deg.

Claim 16

Dependent Claim 167 words

A colour toner composition, comprising a colour toner which in turn comprises at least a binder resin and a colorant, and a fluidity improver, the colour toner composition having an agglomeration degree of 25% or below and an apparent density of 0.2 to 1.5 g/cm³, and the colour toner having a volume-average particle size of 11.0 to 14.0 microns, containing 30% by number or less of particles having sizes below 6.35 microns and containing 9 % by weight or less of particles having sizes above 20.2 microns, having an apparent viscosity at 100°C of 10⁴ to 5 × 10⁵ poise, apparent viscosity at 90°C of 5 × 10⁴ to 5 × 10⁶ poise, a DSC heat-absorption peak at 58 to 72°C, and a gloss of 5.0% or higher, and showing a triboelectric charge of -5 to -20 micro-C/g with respect a ferrite carrier coated with fluorine- containing resin-styrene type resin containing 70 wt. % or more of carrier particles having sizes of 250 mesh-pass and 350 mesh-on.

Claim 17

Dependent Claim 167 words

A colour toner composition, comprising a colour toner which in turn comprises at least a binder resin and a colorant, and a fluidity improver, the colour toner composition having an agglomeration degree of 25% or below and an apparent density of 0.2 to 1.5 g/cm³, and the colour toner having a volume-average particle size of 11.0 to 14.0 microns, containing 30% by number or less of particles having sizes below 6.35 microns and containing 9 % by weight or less of particles having sizes above 20.2 microns, having an apparent viscosity at 100°C of 10⁴ to 5 × 10⁵ poise, apparent viscosity at 90°C of 5 × 10⁴ to 5 × 10⁶ poise, a DSC heat-absorption peak at 58 to 72°C, and a gloss of 5.0% or higher, and showing a triboelectric charge of -5 to -20 micro-C/g with respect a ferrite carrier coated with fluorine- containing resin-styrene type resin containing 70 wt. % or more of carrier particles having sizes of 250 mesh-pass and 350 mesh-on.

Claim 18

Dependent Claim 29 words

A colour toner composition according to claim 15, wherein the binder resin comprises a styrene-acrylic acid ester type resin, a styrene-methacrylic acid ester type resin or a polyester resin.

Claim 19

Dependent Claim 62 words

A colour toner composition according to claim 15, wherein the binder resin comprises a polyester formed from a di- or more-functional carboxylic acid and a bisphenol derivative represented by the formula: wherein R denotes an ethylene or propylene group; x and y are respectively a positive integer of 1 or more providing the sum (x+y) of 2 to 10 on an average.

Claim 20

Dependent Claim 36 words

A colour toner composition according to claim 17, wherein the carboxylic acid is selected from the group consisting of fumaric acid, maleic acid, maleic anhydride, phthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid and mixture thereof.

Claim 21

Dependent Claim 45 words

A colour toner composition according to any of claims 15 to 18, wherein the fluidity improver is vinylidene fluoride resin fine powder, polytetrafluoroethylene fine powder, zinc stearate, calcium stearate, lead stearate, zinc oxide powder, silica fine powder or a mixture of two or more thereof.

Claim 22

Dependent Claim 17 words

A colour toner composition according to claim 19, wherein the fluidity improver is hydrophobic silica fine powder.

Claim 23

Dependent Claim 31 words

A colour toner composition according to claim 20, wherein the fluidity improver is hydrophobic silica fine powder having a hydrophobicity of 30 to 80 as measured by the methanol titration test.

Claim 24

Dependent Claim 29 words

A colour toner composition according to any of claims 15 to 21, comprising 0.01 to 10 wt. parts of the fluidity improver per 100 wt. parts of the toner.

Claim 25

Dependent Claim 25 words

A colour toner composition according to claim 22 comprising 0.1 to 5 wt. parts of the fluidity improver per 100 wt. parts of the toner.

Claim 26

Dependent Claim 109 words

A colour toner composition according to any of claims 15 to 23, having an agglomeration degree of 1.0 to 20 %, and an apparent density of 0.25 to 1.0 g/cm³, and wherein the colour toner has a volume-average particle size of 11.5 to 13.5 microns, contains 25 % by number or less of particles having sizes below 6.35 microns and contains 7 % by weight or less of particles having sizes above 20.2 microns, and has an apparent viscosity at 90°C of 7.5 × 10⁴ to 2 × 10⁶ poise, an apparent viscosity at 100°C of 10⁴ to 3.0 × 10⁶ and a gloss of 7.0 % or higher.

Claim 27

Dependent Claim 95 words

A colour toner composition according to claim 24, having an agglomeration degree of 1.0 to 10 %, and an apparent density of 0.3 to 0.8 g/cm³, and wherein the colour toner has a volume-average particle size of 11.7 to 13.3 microns, contains 20 % by number or less of particles having sizes below 6.35 microns and contains 5 % by weight or less of particles having sizes above 20.2 microns, and has an apparent viscosity at 90°C of 10⁵ to 10⁶ poise, and an apparent viscosity at 100°C of 10⁴ to 2 × 10⁵ poise.

Claim 28

Dependent Claim 59 words

A colour toner composition according to any of claims 15 to 25 wherein the colour toner is a yellow toner comprising by weight, 0.1 to 12.0 parts of a yellow colorant per 100 parts of the binder resin and having chromaticity values of a* = -6.5 to -26.5, b* = 73.0 to 93.0, and L* = 77.0 to 97.0.

Claim 29

Dependent Claim 27 words

A colour toner composition according to claim 26, which contains by weight, 0.5 to 7.0 parts of the yellow colorant per 100 parts of the binder resin.

Claim 30

Dependent Claim 37 words

A colour toner composition according to claim 26 or 27, wherein the yellow colorant is selected from C.I. Pigment Yellow 17, C.I. Pigment Yellow 15, C.I. Pigment Yellow 13, C.I. Pigment Yellow 14, C.I. Pigment Yellow 12.

Claim 31

Dependent Claim 36 words

A colour toner composition according to any of claims 26 to 28, wherein the yellow toner has chromaticity values of a* = -11.5 to -21.5, b* = 78.0 to 88.0, and L* = 82.0 to 92.0.

Claim 32

Dependent Claim 31 words

A colour toner according to claim 29, wherein the yellow toner has chromaticity values of a* = -12.5 to -20.5, b* = 79.0 to 87.0, and L* = 83.0 to 91.0.

Claim 33

Dependent Claim 59 words

A colour toner composition according to any of claims 15 to 25, wherein the colour toner is a magenta toner containing, by weight, 0.1 to 15.0 parts of a magenta colorant per 100 parts of the binder resin and having chromaticity values of a* = 60.0 to 80.0, b* = -12.0 to -32.0, and L* = 40.0 to 60.0.

Claim 34

Dependent Claim 27 words

A colour toner composition according to claim 31, which contains, by weight, 0.1 to 9.0 parts of the magenta colorant per 100 parts of the binder resin.

Claim 35

Dependent Claim 38 words

A colour toner composition according to claim 31 to 32, wherein the magenta colorant is selected from C.I. Pigment Red 5, C.I. Pigment Red 3, C.I. Pigment Red 2, C.I. Pigment Red 6 and C.I. Pigment Red 7.

Claim 36

Dependent Claim 35 words

A colour toner composition according to claim 31, 32 or 33, wherein the magenta toner has chromaticity values of a* = 65.0 to 75.0, b* = -17.0 to -27.0, and L* = 40.0 to 55.0.

Claim 37

Dependent Claim 31 words

A colour toner composition according to claim 34, wherein the magenta toner has chromaticity values of a* = 66.0 to 74.0, b* -18.0 to -26.0, and L* = 44.0 to 54.0.

Claim 38

Dependent Claim 59 words

A colour toner composition, according to any of claims 15 to 25, wherein the colour toner is a cyan toner containing by weight 0.1 to 15.0 parts of a cyan colorant per 100 parts of the binder resin and having chromaticity values of a* = -8.0 to -28.0, b* = -30.0 to -5.0, and L* = 39.0 to 59.0.

Claim 39

Dependent Claim 28 words

A colour toner composition according to claim 36, which contains by weight 0.1 to 9 wt. parts of the cyan colorant per 100 parts of the binder resin.

Claim 40

Dependent Claim 35 words

A cyan toner composition according to claim 36 or 37, wherein the cyan colorant is selected from C.I. Pigment Blue 15, C.I. Pigment Blue 16, and copper phthalocyanine pigments having 2 - 3 carboxybenzamidomethyl groups.

Claim 41

Dependent Claim 35 words

A colour toner composition according to claim 36, 37 or 38, wherein the cyan toner has chromaticity values of a* = -10.0 to -27.0, b* = -33.0 to -45.0, and L* = 44.0 to 59.0.

Claim 42

Dependent Claim 32 words

A cyan toner composition according to claim 39, wherein the cyan toner has chromaticity vlaues of a* = -14.0 to -25.0, b* = -35.0 to -44.0, and L* = 45.0 to 57.0.

Claim 43

Dependent Claim 67 words

A colour toner composition, according to any of claims 15 to 25, wherein the colour toner is a black toner which contains two or more colorants, shows a reflectance of 40 % or highter in the near infrared wavelength region of 900 to 1000 nm and which has chromaticity values of a* = -3.5 to 6.5, b* = -6.0 to 4.0, and L* = 26.0 to 36.0.

Claim 44

Dependent Claim 26 words

A colour toner composition according to claim 41, which contains, by weight, 3 to 15 parts of the colorants per 100 parts of the binder resin.

Claim 45

Dependent Claim 27 words

A colour toner composition according to claim 41 or 42, wherein the colorants comprise a disazo-type yellow pigment, a monoazo-type red pigment and a phthalocyanine-type blue pigment.

Claim 46

Dependent Claim 33 words

A colour toner composition according to claim 43, wherein the disazo-type yellow pigment, the monoazo-type red pigment and the phthalocyanine-type blue pigment are mixed in weight ratios of 1:1.5 to 2.5:0.5 to 1.5.

Claim 47

Dependent Claim 42 words

A black toner composition according to claim 43 or 44, wherein the disazo-type yellow pigment is C.I. Pigment Yellow 17 or 13; the monoazo-type red pigment is C.I. Pigment Red 5 or 7; and phthalocyanine-type blud pigment is C.I. Pigment Blue 15.

Claim 48

Dependent Claim 36 words

A colour toner composition according to any of claims 41 to 45, wherein the black toner has chromaticity values of a* = -2.0 to 5.5, b* = -5.0 to 3.0, and L* = 27.0 to 35.0.

Claim 49

Dependent Claim 74 words

A multi-colour toner kit comprising a yellow toner package containing a yellow toner composition according to any of claims 26 to 30, a magenta toner package containing a magenta toner composition according to any of claims 31 to 35, a cyan toner package containing a cyan toner composition according to any of claims 36 to 40 and a black toner package containing a black toner composition according to any of claims 41 to 46.

Claim 50

Dependent Claim 33 words

A colour developer for developing electrostatic latent images, comprising; (1) a colour toner composition according to any of claims 15 to 45, and (2) a ferrite carrier coated with fluorine-containing resin-styrene type resin.

Claim 51

Dependent Claim 21 words

A colour developer according to claim 48, wherein the ferrite carrier has an average particle size of 20 to 100 microns.

Claim 52

Dependent Claim 21 words

A colour developer according to claim 49, wherein the ferrite carrier has an average particle size of 25 to 70 microns.

Claim 53

Dependent Claim 21 words

A colour developer according to claim 50, wherein the ferrite carrier has an average particle size of 30 to 65 microns.

Claim 54

Dependent Claim 40 words

A colour developer according to any of claims 48 to 51, wherein the ferrite carrier is coated with 0.01 to 5 wt. % based on the carrier of a mixture of the fluorine containing resin and the styrene type resin.

Claim 55

Dependent Claim 36 words

A colour developer according to claim 52, wherein the ferrite carrier is coated with 0.1 to 1 wt. % based on the carrier of a mixture of the fluorine containing resin and the styrene type resin.

Claim 56

Dependent Claim 29 words

A colour developer according to any of claims 48 to 51, wherein the fluorine-containing resin and the styrene type resin are mixed in a weight ratio 90:10 to 20:80.

Claim 57

Dependent Claim 26 words

A colour developer according to claim 52, wherein the fluorine-containing resin and the styrene type resin are mixed in a weight ratio of 70:30 to 30:70.

Claim 58

Dependent Claim 39 words

A colour developer according to any of claims 48 to 55, wherein the fluorine-containing resin is polyvinylidene fluoride, polytetrafluoroethylene or vinylidene fluoride-tetrafluoroethylene copolymer, and the styrene-type resin is styrene-methyl methacrylate copolymer, styrene-2-ethylhexyl acrylate copolymer or styrene-2-ethylhexyl acrylate-methyl methacrylate copolymer.

Claim 59

Dependent Claim 25 words

A colour developer according to claim 56, wherein the fluorine-containing resin is vinylidene fluoride-tetrafluoroethylene copolymer, and the styrene type resin is styrene-2-ethylhexyl acrylate-methyl methacrylate copolymer.

Color toner and two-component developer containing same

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag