US5774771A — Image forming method and apparatus using a partic…

Claim 1

Independent Claim 200 words

An image forming method comprising; a developing step of developing an electrostatic latent image by the use of a developer to form a toner image on an electrostatic latent image bearing member; a primary transfer step of transferring the toner image onto an intermediate transfer member to which a voltage is applied; and a secondary transfer step of transferring onto a transfer medium the toner image held on the intermediate transfer member, while a transfer means to which a voltage is applied is pressed against the transfer medium; wherein said developer has a toner, and the toner is a black magnetic toner having at least i) black magnetic toner particles formed of 100 parts by weight of a binder resin with 30 to 200 parts by weight of a magnetic material dispersed therein and ii) an inorganic fine powder; said black magnetic toner having the value of shape factor SF-1 of 120≦SF-1≦160, the value of shape factor SF-2 of 115≦SF-2≦140, and the value of ratio B/A of 1.0 or less which is the ratio of a value B obtained by subtracting 100 from the value of SF-2 to a value A obtained by subtracting 100 from the value of SF-1.

Claim 2

Dependent Claim 200 words

An image forming method comprising; a developing step of developing an electrostatic latent image by the use of a developer to form a toner image on an electrostatic latent image bearing member; a primary transfer step of transferring the toner image onto an intermediate transfer member to which a voltage is applied; and a secondary transfer step of transferring onto a transfer medium the toner image held on the intermediate transfer member, while a transfer means to which a voltage is applied is pressed against the transfer medium; wherein said developer has a toner, and the toner is a black magnetic toner having at least i) black magnetic toner particles formed of 100 parts by weight of a binder resin with 30 to 200 parts by weight of a magnetic material dispersed therein and ii) an inorganic fine powder; said black magnetic toner having the value of shape factor SF-1 of 120≦SF-1≦160, the value of shape factor SF-2 of 115≦SF-2≦140, and the value of ratio B/A of 1.0 or less which is the ratio of a value B obtained by subtracting 100 from the value of SF-2 to a value A obtained by subtracting 100 from the value of SF-1.

Claim 3

Dependent Claim 79 words

The image forming method according to claim 1, wherein said black magnetic toner satisfies the following conditions 3.0≦Sb/St≦7.0 Sb≧St×1.5+1.5 wherein Sb represents a specific surface area (m 2 /cm 3 ) per unit volume of said black magnetic toner, as measured by the BET method; and St represents a specific surface area (m 2 /cm 3 ) per unit volume as calculated from weight average particle diameter on the assumption that the black magnetic toner particles are truly spherical.

Claim 4

Dependent Claim 23 words

The image forming method according to claim 1, wherein black magnetic toner has the value of ratio B/A of from 0.20 to 0.90.

Claim 5

Dependent Claim 28 words

The image forming method according to claim 1, wherein said toner has a charge quantity per unit volume of from 30 C/m 3 to -80 C/m 3 .

Claim 6

Dependent Claim 37 words

The image forming method according to claim 1, wherein said inorganic fine powder is an inorganic fine powder of a material selected from the group consisting of titania, alumina, silica, and double oxides of any of these.

Claim 7

Dependent Claim 26 words

The image forming method according to claim 1 or 6, wherein said inorganic fine powder is an inorganic fine powder having been subjected to hydrophobic treatment.

Claim 8

Dependent Claim 26 words

The image forming method according to claim 6, wherein said inorganic fine powder is an inorganic fine powder having been treated with at least silicone oil.

Claim 9

Dependent Claim 42 words

The image forming method according to claim 1, wherein said inorganic fine powder has an average primary particle diameter of 30 nm or smaller, and said toner further contains a second fine powder having an average particle diameter larger than 30 nm.

Claim 10

Dependent Claim 27 words

The image forming method according to claim 8, wherein said second fine powder having an average particle diameter larger than 30 nm is an inorganic fine powder.

Claim 11

Dependent Claim 27 words

The image forming method according to claim 9, wherein said second fine powder having an average particle diameter larger than 30 nm is a fine resin powder.

Claim 12

Dependent Claim 28 words

The image forming method according to claim 8, wherein said second fine powder having an average particle diameter larger than 30 nm has substantially a spherical particle shape.

Claim 13

Dependent Claim 42 words

The image forming method according to claim 1, wherein said black magnetic toner particles have has a specific surface area per unit volume, of from 1.2 m 2 /cm 3 to 2.5 m 2 /cm 3 as measured by the BET method.

Claim 14

Dependent Claim 45 words

The image forming method according to claim 1 or 12, wherein said black magnetic toner particles have has a 60% pore radius of 3.5 nm or smaller in the integrating pore area percentage curve of pores of from 1 nm to 100 nm in size.

Claim 15

Dependent Claim 40 words

The image forming method according to claim 1, wherein said black magnetic toner particles have has a peak of low-molecular weight in its molecular weight distribution as measured by gel permeation chromatography, in the range of from 3,000 to 15,000.

Claim 16

Dependent Claim 194 words

The image forming method according to claim 1, wherein: an electrostatic latent image is developed with a developer having a yellow toner to form a yellow toner image on the electrostatic latent image bearing member, and the yellow toner image is transferred onto the intermediate transfer member; an electrostatic latent image is developed with a developer having a magenta toner to form a magenta toner image on the electrostatic latent image bearing member, and thereafter the magenta toner image is transferred onto the intermediate transfer member; an electrostatic latent image is developed with a developer having a cyan toner to form a cyan toner image on the electrostatic latent image bearing member, and thereafter the cyan toner image is transferred onto the intermediate member; an electrostatic latent image is developed with a developer having the black magnetic toner to form a black magnetic toner image on the electrostatic latent image bearing member, and thereafter the black magnetic toner image is transferred onto the intermediate transfer member; and the yellow toner image, magenta toner image, cyan toner image and black magnetic toner image held on the intermediate transfer member are transferred onto the transfer medium.

Claim 17

Dependent Claim 37 words

The image forming method according to claim 15, wherein said black magnetic toner has the value of SF-2 greater by at least 5 than the value of SF-2 of said yellow toner, magenta toner or cyan toner.

Claim 18

Dependent Claim 61 words

The image forming method according to claim 15, wherein said yellow toner has SF-1 of from 100 to 170 and SF-2 of from 100 to 139, said magenta toner has SF-1 of from 100 to 170 and SF-2 of from 100 to 139, and said cyan toner has SF-1 of from 100 to 170 and SF-2 of from 100 to 139.

Claim 19

Dependent Claim 61 words

The image forming method according to claim 15, wherein said yellow toner has SF-1 of from 100 to 160 and SF-2 of from 100 to 130, said magenta toner has SF-1 of from 100 to 160 and SF-2 of from 100 to 130, and said cyan toner has SF-1 of from 100 to 160 and SF-2 of from 100 to 130.

Claim 20

Dependent Claim 61 words

The image forming method according to claim 16, wherein said yellow toner has SF-1 of from 100 to 150 and SF-2 of from 100 to 125, said magenta toner has SF-1 of from 100 to 150 and SF-2 of from 100 to 125, and said cyan toner has SF-1 of from 100 to 150 and SF-2 of from 100 to 125.

Claim 21

Dependent Claim 40 words

The image forming method according to claim 15, wherein said black toner is a magnetic toner, said wherein said yellow toner is a non-magnetic toner, said magenta toner is a non-magnetic toner, and said cyan toner is a non-magnetic toner.

Claim 22

Dependent Claim 144 words

The image forming method according to claim 15, wherein said black magnetic toner has black magnetic toner particles produced by melt-kneading a mixture having at least a binder resin and a magnetic material, cooling the resulting melt-kneaded product, and pulverizing the melt-kneaded product cooled; said yellow toner has yellow toner particles produced by forming fine particles by polymerization in an aqueous medium of a polymerizable monomer composition containing at least a polymerizable monomer and a yellow colorant; said magenta toner has magenta toner particles produced by forming fine particles by polymerization in an aqueous medium of a polymerizable monomer composition containing at least a polymerizable monomer and a magenta colorant; and said cyan toner has cyan toner particles produced by forming fine particles by polymerization in an aqueous medium of a polymerizable monomer composition containing at least a polymerizable monomer and a cyan colorant.

Claim 23

Dependent Claim 30 words

The image forming method according to claim 1, wherein the surface of said electrostatic latent image bearing member has a contact angle to water, of not smaller than 85 degrees.

Claim 24

Dependent Claim 25 words

The image forming method according to claim 22, wherein said electrostatic latent image bearing member has a surface layer containing a material having fluorine atoms.

Claim 25

Dependent Claim 26 words

The image forming method according to claim 23, wherein said material having fluorine atoms is a fine powder of a compound or resin having fluorine atoms.

Claim 26

Dependent Claim 122 words

The image forming method according to claim 1, wherein said intermediate transfer member and said transfer means each have a surface formed of an elastic layer, said intermediate transfer member shows a volume resistivity lower than the volume resistivity of the transfer means, said intermediate transfer member has a surface hardness ranging from 10 to 40 as measured according to JIS K-6301, said transfer means has a surface hardness greater than the surface hardness of the intermediate transfer member, said transfer means is pressed against said intermediate transfer member so as to form a concave nip on the side of the intermediate transfer member, and said toner image is transferred to the transfer medium while applying a voltage to the transfer means.

Claim 27

Dependent Claim 23 words

The image forming method according to claim 1, wherein said intermediate transfer member has a cylindrical drum for holding the toner image thereon.

Claim 28

Dependent Claim 23 words

The image forming method according to claim 1, wherein said intermediate transfer member has an endless belt for holding the toner image thereon.

Claim 29

Dependent Claim 47 words

The image forming method according to claim 1, wherein said intermediate transfer member has a cylindrical drum for holding the toner image thereon, and said transfer means has a transfer belt by which the toner image held on the cylindrical drum is transferred to the transfer medium.

Claim 30

Dependent Claim 47 words

The image forming method according to claim 1, wherein said intermediate transfer member has an endless belt for holding the toner image thereon, and said transfer means has a transfer roller by which the toner image held on the endless belt is transferred to the transfer medium.

Claim 31

Dependent Claim 17 words

The image forming method according to claim 1, wherein said black magnetic toner contains a liquid lubricant.

Claim 32

Dependent Claim 35 words

The image forming method according to claim 30, wherein said liquid lubricant is contained in the toner in the form of lubricant-supported particles containing from 20 to 90 parts by weight of the liquid lubricant.

Claim 33

Dependent Claim 24 words

The image forming method according to claim 30, wherein said liquid lubricant is supported on the magnetic material contained in the black magnetic toner.

Claim 34

Dependent Claim 25 words

The image forming method according to claim 30, wherein said liquid lubricant has a viscosity at 25° C. of from 10 cSt to 200,000 cSt.

Claim 35

Dependent Claim 210 words

An image forming apparatus comprising: an electrostatic latent image bearing member; a developing means having a developer for forming a toner image on the electrostatic latent image bearing member; an intermediate transfer member for holding the toner image transferred from the electrostatic latent image bearing member; said intermediate transfer member having a bias applying means; and a transfer means for transferring the toner image held on the intermediate transfer member, onto a transfer medium; said transfer means having a bias applying means and being provided in the manner that it is pressed against the intermediate transfer member; wherein said developer has a toner, and the toner is a black magnetic toner having at least i) black magnetic toner particles formed of 100 parts by weight of a binder resin with 30 to 200 parts by weight of a magnetic material dispersed therein and ii) an inorganic fine powder; said black magnetic toner having the value of shape factor SF-1 of 120≦SF-1≦160, the value of shape factor SF-2 of 115≦SF-2≦140, and the value of ratio B/A of 1.0 or less which is the ratio of a value B obtained by subtracting 100 from the value of SF-2 to a value A obtained by subtracting 100 from the value of SF-1 .

Claim 36

Dependent Claim 210 words

An image forming apparatus comprising: an electrostatic latent image bearing member; a developing means having a developer for forming a toner image on the electrostatic latent image bearing member; an intermediate transfer member for holding the toner image transferred from the electrostatic latent image bearing member; said intermediate transfer member having a bias applying means; and a transfer means for transferring the toner image held on the intermediate transfer member, onto a transfer medium; said transfer means having a bias applying means and being provided in the manner that it is pressed against the intermediate transfer member; wherein said developer has a toner, and the toner is a black magnetic toner having at least i) black magnetic toner particles formed of 100 parts by weight of a binder resin with 30 to 200 parts by weight of a magnetic material dispersed therein and ii) an inorganic fine powder; said black magnetic toner having the value of shape factor SF-1 of 120≦SF-1≦160, the value of shape factor SF-2 of 115≦SF-2≦140, and the value of ratio B/A of 1.0 or less which is the ratio of a value B obtained by subtracting 100 from the value of SF-2 to a value A obtained by subtracting 100 from the value of SF-1 .

Claim 37

Dependent Claim 79 words

The image forming apparatus according to claim 34, wherein said black magnetic toner satisfies the following conditions 3.0≦Sb/St≦7.0 Sb≧St×1.5+1.5 wherein Sb represents a specific surface area per (m 2 /cm 3 ) unit volume of said black magnetic toner, as measured by the BET method; and St represents a specific surface area (m 2 /cm 3 ) per unit volume as calculated from weight average particle diameter on the assumption that the black magnetic toner particles are truly spherical.

Claim 38

Dependent Claim 24 words

The image forming apparatus according to claim 34, wherein said black magnetic toner has the value of ratio B/A of from 0.20 to 0.90.

Claim 39

Dependent Claim 28 words

The image forming apparatus according to claim 34, wherein said toner has a charge quantity per unit volume of from 30 C/m 3 to -80 C/m 3 .

Claim 40

Dependent Claim 37 words

The image forming apparatus according to claim 34, wherein said inorganic fine powder is an inorganic fine powder of a material selected from the group consisting of titania, alumina, silica, and double oxides of any of these.

Claim 41

Dependent Claim 26 words

The image forming apparatus according to claim 34 or 38, wherein said inorganic fine powder is an inorganic fine powder having been subjected to hydrophobic treatment.

Claim 42

Dependent Claim 26 words

The image forming apparatus according to claim 39, wherein said inorganic fine powder is an inorganic fine powder having been treated with at least silicone oil.

Claim 43

Dependent Claim 42 words

The image forming apparatus according to claim 34, wherein said inorganic fine powder has an average primary particle diameter of 30 nm or smaller, and said toner further contains a second fine powder having an average particle diameter larger than 30 nm.

Claim 44

Dependent Claim 27 words

The image forming apparatus according to claim 41, wherein said second fine powder having an average particle diameter larger than 30 nm is an inorganic fine powder.

Claim 45

Dependent Claim 27 words

The image forming apparatus according to claim 41, wherein said second fine powder having an average particle diameter larger than 30 nm is a fine resin powder.

Claim 46

Dependent Claim 28 words

The image forming apparatus according to claim 41, wherein said second fine powder having an average particle diameter larger than 30 nm has substantially a spherical particle shape.

Claim 47

Dependent Claim 41 words

The image forming apparatus according to claim 34, wherein said black magnetic toner particles have a specific surface area per unit volume, of from 1.2 m 2 /cm 3 to 2.5 m 2 /cm 3 as measured by the BET method.

Claim 48

Dependent Claim 44 words

The image forming apparatus according to claim 34 or 49, wherein said black magnetic toner particles have a 60% pore radius of 3.5 nm or smaller in the integrating pore area percentage curve of pores of from 1 nm to 100 nm in size.

Claim 49

Dependent Claim 39 words

The image forming apparatus according to claim 34, wherein said black magnetic toner particles have a peak of low-molecular weight in its molecular weight distribution as measured by gel permeation chromatography, in the range of from 3,000 to 15,000.

Claim 50

Dependent Claim 95 words

The image forming apparatus according to claim 34, wherein said developing means has a yellow developing assembly having a developer for forming a yellow toner image on the electrostatic latent image bearing member, a magenta developing assembly having a developer for forming a magenta toner image on the electrostatic latent image bearing member, a cyan developing assembly having a developer for forming a cyan toner image on the electrostatic latent image bearing member, and a black developing assembly having a developer for forming a black magnetic toner image on the electrostatic latent image bearing member.

Claim 51

Dependent Claim 37 words

The image forming apparatus according to claim 48, wherein said black magnetic toner has the value of SF-2 greater by at least 5 than the value of SF-2 of said yellow toner, magenta toner or cyan toner.

Claim 52

Dependent Claim 61 words

The image forming apparatus according to claim 48, wherein said yellow toner has SF-1 of from 100 to 170 and SF-2 of from 100 to 139, said magenta toner has SF-1 of from 100 to 170 and SF-2 of from 100 to 139, and said cyan toner has SF-1 of from 100 to 170 and SF-2 of from 100 to 139.

Claim 53

Dependent Claim 61 words

The image forming apparatus according to claim 48, wherein said yellow toner has SF-1 of from 100 to 160 and SF-2 of from 100 to 130, said magenta toner has SF-1 of from 100 to 160 and SF-2 of from 100 to 130, and said cyan toner has SF-1 of from 100 to 160 and SF-2 of from 100 to 130.

Claim 54

Dependent Claim 61 words

The image forming apparatus according to claim 48, wherein said yellow toner has SF-1 of from 100 to 150 and SF-2 of from 100 to 125, said magenta toner has SF-1 of from 100 to 150 and SF-2 of from 100 to 125, and said cyan toner has SF-1 of from 100 to 150 and SF-2 of from 100 to 125.

Claim 55

Dependent Claim 40 words

The image forming apparatus according to claim 48, wherein said black toner is a magnetic toner, said wherein said yellow toner is a non-magnetic toner, said magenta toner is a non-magnetic toner, and said cyan toner is a non-magnetic toner.

Claim 56

Dependent Claim 144 words

The image forming apparatus according to claim 41, wherein said black magnetic toner has black magnetic toner particles produced by melt-kneading a mixture having at least a binder resin and a magnetic material, cooling the resulting melt-kneaded product, and pulverizing the melt-kneaded product cooled; said yellow toner has yellow toner particles produced by forming fine particles by polymerization in an aqueous medium of a polymerizable monomer composition containing at least a polymerizable monomer and a yellow colorant; said magenta toner has magenta toner particles produced by forming fine particles by polymerization in an aqueous medium of a polymerizable monomer composition containing at least a polymerizable monomer and a magenta colorant; and said cyan toner has cyan toner particles produced by forming fine particles by polymerization in an aqueous medium of a polymerizable monomer composition containing at least a polymerizable monomer and a cyan colorant.

Claim 57

Dependent Claim 30 words

The image forming apparatus according to claim 34, wherein the surface of said electrostatic latent image bearing member has a contact angle to water, of not smaller than 85 degrees.

Claim 58

Dependent Claim 25 words

The image forming apparatus according to claim 55, wherein said electrostatic latent image bearing member has a surface layer containing a material having fluorine atoms.

Claim 59

Dependent Claim 26 words

The image forming apparatus according to claim 56, wherein said material having fluorine atoms is a fine powder of a compound or resin having fluorine atoms.

Claim 60

Dependent Claim 122 words

The image forming apparatus according to claim 34, wherein said intermediate transfer member and said transfer means each have a surface formed of an elastic layer, said intermediate transfer member shows a volume resistivity lower than the volume resistivity of the transfer means, said intermediate transfer member has a surface hardness ranging from 10 to 40 as measured according to JIS K-6301, said transfer means has a surface hardness greater than the surface hardness of the intermediate transfer member, said transfer means is pressed against said intermediate transfer member so as to form a concave nip on the side of the intermediate transfer member, and said toner image is transferred to the transfer medium while applying a voltage to the transfer means.

Claim 61

Dependent Claim 23 words

The image forming apparatus according to claim 34, wherein said intermediate transfer member has a cylindrical drum for holding the toner image thereon.

Claim 62

Dependent Claim 23 words

The image forming apparatus according to claim 34, wherein said intermediate transfer member has an endless belt for holding the toner image thereon.

Claim 63

Dependent Claim 47 words

The image forming apparatus according to claim 34, wherein said intermediate transfer member has a cylindrical drum for holding the toner image thereon, and said transfer means has a transfer belt by which the toner image held on the cylindrical drum is transferred to the transfer medium.

Claim 64

Dependent Claim 47 words

The image forming apparatus according to claim 34, wherein said intermediate transfer member has an endless belt for holding the toner image thereon, and said transfer means has a transfer roller by which the toner image held on the endless belt is transferred to the transfer medium.

Claim 65

Dependent Claim 17 words

The image forming apparatus according to claim 34, wherein said black magnetic toner contains a liquid lubricant.

Claim 66

Dependent Claim 37 words

The image forming apparatus according to claim 63, wherein said liquid lubricant is contained in the black magnetic toner in the form of lubricant-supported particles containing from 20 to 90 parts by weight of the liquid lubricant.

Claim 67

Dependent Claim 23 words

The image forming apparatus according to claim 63, said liquid lubricant is supported on the magnetic material contained in the black magnetic toner.

Claim 68

Dependent Claim 25 words

The image forming apparatus according to claim 63, wherein said liquid lubricant has a viscosity at 25° C. of from 10 cSt to 200,000 cSt.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2001-06-29	2001-12-29	2002-06-30	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2005-06-29	2005-12-29	2006-06-30	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2009-06-29	2009-12-29	2010-06-30	$7700.00	Window Closed / Lapsed

Image forming method and apparatus using a particular toner

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