JP2002287408A - Electrostatic charge image developing toner, method for manufacturing the same and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner which causes no slipping of toner particles from a cleaning device during forming an image, which decreases the wear amount of the cleaning blade of the cleaning device, which prevents the blurring of images and which shows little environment dependence of the image density of the formed images, and to provide a method for manufacturing the toner and an image forming device. SOLUTION: In the electrostatic charge image developing toner having toner particles obtained by polymerizing polymerizable monomers in a water-based medium, the toner contains a lithium salt of a fatty acid as an external additive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic image, a method for producing the same, and an image forming apparatus.

[0002]

2. Description of the Related Art At present, an electrostatic latent image developing method represented by an electrophotographic method is widely used in image forming apparatuses such as printers, copiers and facsimile machines.

[0003] The reason for this is that it is a highly complete method for stably obtaining a high-speed and high-quality image, but some problems still remain.

For example, conventionally, in a toner prepared by a pulverization method, the material dispersed in the toner is unevenly present on the fracture surface, and the surface properties of the toners are difficult to be constant, and variations occur in a transfer process. And there is a problem that color reproducibility as a color image is apt to be reduced.

On the other hand, it is desired to reduce the particle size of the electrostatic latent image developing toner from the viewpoint of high image quality. In recent years, polymerization toners have been actively developed as a method for producing small particle size toners. The polymerized toner is prepared by associating or salting-out, aggregating, and fusing the resin particles and, if necessary, the colorant particles to prepare an irregular shaped toner, or dispersing a radical polymerizable monomer and a colorant. Then, there is a method in which droplets are dispersed in an aqueous medium or the like so as to have a desired toner particle diameter, and suspension polymerization is performed.

However, since the toner particles produced by applying the suspension polymerization method are composed of spherical or curved surfaces, a toner having a uniform surface property can be formed, and the uniformity of charge among the toners is high. However, there is a problem that the spherical shape of the particles increases the adhesion to the latent image carrier, and the cleaning tends to be reduced.

[0007] In particular, in order to achieve high image quality, it is desirable to adjust the toner particles to a small particle size and to make the shape of the toner particles uniform. However, such toner particles have the following problems. There are problems such as slippage of toner particles from the cleaning device during image formation, large wear of the cleaning blade of the cleaning device, blurring of the image, and a large environmental dependence of the image density of the formed image. It has been desired to solve such problems.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to prevent toner particles from slipping through a cleaning device during image formation, reduce the amount of wear of a cleaning blade of the cleaning device, prevent image blurring, and An object of the present invention is to provide a toner for developing an electrostatic image, in which the image density of a formed image is less dependent on the environment, a method of manufacturing the same, and an image forming apparatus.

[0009]

The above objects of the present invention have been attained by the following items 1 to 18.

[0010] 1. An electrostatic image developing toner having toner particles obtained by polymerizing a polymerizable monomer in an aqueous medium, wherein the toner has a fatty acid lithium salt as at least one of external additives. An electrostatic image developing toner.

2. The fatty acid lithium salt has a water content of 0.1% by mass to 1.4% by mass, and a free fatty acid amount in the toner is 0.01% by mass to 0.7% by mass. For developing electrostatic images.

3. 3. The toner for developing an electrostatic image as described in 1 or 2, wherein the lithium fatty acid salt is lithium stearate.

4. Wherein the toner particles are obtained by coagulating and fusing resin particles in an aqueous medium.
The toner for developing an electrostatic image according to any one of the above items.

5. The toner particles are used as an external additive on the surface of the organic fine particles having an average particle size of 0.1 μm to 5.0 μm,
5. The electrostatic image developing toner according to any one of items 1 to 4, further comprising inorganic / organic composite fine particles having inorganic fine particles having a primary average particle diameter of 5 nm to 100 nm fixed thereto.

6. Number average particle diameter of toner particles is 2 μm or more
6. The electrostatic image developing method according to any one of 1 to 5, wherein the coefficient of variation of the shape coefficient is 16% or less, and the number variation coefficient in the number particle size distribution is 27% or less. toner.

[7] Number average particle diameter of toner particles is 2 μm or more
Any of 1 to 5 above, wherein the ratio of the toner particles having a shape coefficient of 1.0 to 1.6 to all the toner particles is 65% by number or more.
Item 14. The toner for developing an electrostatic image according to item 8.

8. Number average particle diameter of toner particles is 2 μm or more
Any one of the above items 1 to 5, wherein the ratio of the toner particles having a shape factor of 1.2 to 1.6 to all the toner particles is 65% by number or more.
Item 14. The toner for developing an electrostatic image according to item 8.

9. Number average particle diameter of toner particles is 2 μm or more
The toner for developing an electrostatic image according to any one of the above items 1 to 8, wherein the ratio of the toner particles having no corners to all toner particles is 50% by number or more.

10. Assuming that the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is defined as 0.
The relative frequency (m1) of the toner particles included in the most frequent class in the histogram showing the number-based particle size distribution divided into a plurality of classes at 23 intervals, and the above-described class included in the next most frequent class after the most frequent class Relative frequency of toner particles (m2)
The electrostatic charge image developing toner according to any one of 1 to 9 above, wherein the sum (M) of the toner is 70% or more.

11. 11. The method according to any one of items 1 to 10, wherein a ratio of toner particles having no corners to all toner particles is 50% by number or more and a number variation coefficient in a number particle size distribution is 27% or less. Charge image developing toner.

[12] The ratio of the toner particles having a shape coefficient in the range of 1.2 to 1.6 to all the toner particles is 65% by number or more, and the variation coefficient of the shape coefficient is 16% or less. The toner for developing an electrostatic image according to any one of the above items.

13. Wherein the toner particles are produced through a step of salting out, aggregating, and fusing the composite resin particles obtained by a multi-stage polymerization method and the colorant particles;
13. The toner for developing an electrostatic image according to any one of items 12 to 12.

14. In the GPC (gel permeation chromatography) measurement of the toner, the peak or shoulder is at least 100,000 to 1,000,000.
14. The toner for developing an electrostatic image according to any one of the items 1 to 13, wherein the toner is present in a range of from 1,000 to 50,000.

[15] In the GPC (gel permeation chromatography) measurement of the toner, the peak or shoulder is at least 100,000 to 1,000,000.
00, 25,000-100,000 and 1,000
The above-mentioned items 1 to 1, wherein
4. The toner for developing an electrostatic charge image according to any one of 3.

16. The electrostatic image formed on the organic photoreceptor is developed with a developer having the electrostatic image developing toner according to any one of 1 to 15, and the toner image visualized by the development is developed. An image forming apparatus, comprising: a cleaning device that removes toner remaining on the organic photoconductor after transferring from the organic photoconductor to a transfer material.

17. The image according to the above item 16, wherein the organic photoreceptor has a configuration in which a photosensitive layer is provided on a conductive support, and the surface layer of the photosensitive layer contains polycarbonate having an average molecular weight of 40,000 or more. Forming equipment.

18. 16. In producing the toner for developing an electrostatic image according to any one of the items 1 to 15, particles are formed in an aqueous medium, and after drying the particles, the fatty acid lithium salt is 0.005% by mass to 0.1% by mass. A method for producing a toner for developing an electrostatic image, characterized in that toner particles are produced by external addition in a range of 3% by mass.

Hereinafter, the present invention will be described in detail. In the present invention, in a toner for electrostatic image development having toner particles obtained by polymerizing a polymerizable monomer in an aqueous medium,
When the toner uses a fatty acid lithium salt as an external additive, the toner particles do not slip through the cleaning device during image formation, the amount of wear of the cleaning blade of the cleaning device is reduced, and there is no image blur, and It is possible to provide a toner for developing an electrostatic image, a method for manufacturing the same, and an image forming apparatus, in which the image density of the formed image is less dependent on the environment.

The fatty acid lithium salt according to the present invention will be described. Lithium fatty acid salt according to the present invention used as an external additive, specifically, lithium undecylate, lithium laurate, lithium tridecylate, lithium dodecylate, lithium myristate, lithium palmitate, lithium pentadecylate, lithium stearate Lithium oxide,
Long-chain fatty acid lithium, such as lithium behenate, lithium heptadecylate, lithium arachate, lithium montanate, lithium oleate, lithium linoleate, lithium arachidonic acid, and lithium behenate.

Among the above, lithium stearate is particularly preferably used in the present invention.

The fatty acid portion of the fatty acid lithium salt according to the present invention may be composed of a single fatty acid or a mixed fatty acid.

As a method for producing a fatty acid lithium salt according to the present invention, any of the following methods may be used.

Production method (1): A solid lithium salt and a solid higher fatty acid which are wetted with water are used as raw materials, and the raw material is used as a solid phase reaction between the lithium salt and the higher fatty acids in a closed space. Stirring while heating so as to maintain the carbon dioxide gas generated during the heating and stirring,
The raw materials are reacted so as not to escape to the outside to obtain a fatty acid lithium salt.

Production method (2): After adding water equivalent to 2.5 times the amount of the fatty acid to lithium carbonate, the liquid temperature is maintained at 80 ° C., and the fatty acid previously melted is stirred while the liquid is stirred. By addition, a fatty acid lithium salt is obtained.

The particle size of the fatty acid lithium salt according to the present invention is as follows:
From the viewpoint of obtaining good cleaning properties, it is preferable that the passing amount of mesh having a mesh size of 75 μm is 99%. From the viewpoint of improving the humidity stability during charging and preventing the occurrence of image blur, the water content of the fatty acid lithium salt according to the present invention is preferably from 0.1% by mass to 1.4% by mass, and particularly preferably. , 0.3% by mass to 1.2% by mass.

Here, the water content is measured by the Karl Fischer method. In addition, from the viewpoint of preventing contamination of a charging member such as a carrier and a developing roll and appropriately preventing wear of a cleaning blade, the amount of free fatty acid in the toner of the present invention is preferably 0.01% by mass to 0.9% by mass. Particularly preferably, it is 0.05% by mass to 0.6% by mass.

The free fatty acid in the toner of the present invention is added as an additive during the process of producing toner particles.
Fatty acids contained in the mixed fatty acid lithium salt are present in the toner without adhering to the toner particle surfaces.

In order to improve the chargeability stability by dispersing in the toner, a fatty acid lithium salt having an average particle size of 4 μm or less and particles having a size of more than 10 μm of 4% by mass or less in the fatty acid lithium salt is used. Preferably, it is used.

The addition amount of the fatty acid lithium salt according to the present invention to the toner is preferably about 0.1 to 5% by mass based on the toner.

The inorganic / organic composite fine particles used in the present invention will be described. In the present invention, inorganic / organic composite fine particles are preferably used as abrasive particles. The inorganic / organic composite fine particles have a spherical shape, the surface is an inorganic fine powder having a high hardness, and the core uses relatively elastic organic fine particles. Without causing scratches on the photoconductor or cleaning blade,
Demonstrate stable cleaning properties.

The primary average particle size of the inorganic fine particles constituting the inorganic / organic composite fine particles is from 5 nm to 100 nm from the viewpoint of improving the cleaning property, the polishing property, and the filming resistance.
And more preferably 10 nm to 65 nm. The primary average particle diameter of the inorganic fine particles refers to the number-based average particle diameter measured by an image analyzer when observed with a scanning electron microscope.

The constituent materials of the inorganic fine particles include silicon oxide, titanium oxide, aluminum oxide, zinc oxide, zirconium oxide, cerium oxide, tungsten oxide, antimony oxide, copper oxide, tellurium oxide, manganese oxide, barium titanate, and titanate. Strontium, magnesium titanate, silicon nitride, carbon nitride and the like are used.

The organic fine particles constituting the inorganic / organic composite fine particles are preferably resin particles made of an acrylic polymer, a styrene polymer, a styrene-acryl polymer or the like.

The acrylic polymer constituting the organic fine particles is a homopolymer or a copolymer obtained by polymerizing a monomer selected from acrylic acid or acrylic acid ester, methacrylic acid or methacrylic acid ester. Acrylic monomers used to obtain such an acrylic polymer include acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, and n-acrylate
-Octyl, dodecyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-methyl methacrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, methacryl Propyl acrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylamino methacrylate Examples of styrene monomers such as ethyl include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene,
p-ethylstyrene, 2,4-dimethylstyrene, p-
n-butylstyrene, p-tert-butylstyrene,
p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,
4-dichlorostyrene and the like. A styrene-based polymer can be obtained from one or more of the above-mentioned styrene-based monomers. In the present invention, one or more other monomers are copolymerized as necessary. There may be. In this case, it is preferable to use a styrene-based monomer in a proportion of 50% by mass or more in the monomer composition.

The styrene-acrylic copolymer constituting the organic fine particles is obtained by using one or more of the above-mentioned acrylic monomers and one or more of the above-mentioned styrene monomers. If necessary, one or more other monomers may be copolymerized. In this case, in the monomer composition, it is preferable to use the acrylic monomer and the styrene monomer in a ratio of 50% by mass or more. As the other monomer, acrylonitrile, methacrylonitrile, acrylic acid or methacrylic acid derivatives such as acrylamide, vinyl acetate, vinyl butyrate, vinyl esters such as vinyl benzoate, vinyl methyl ether, vinyl ether such as vinyl ethyl ether , Vinyl ketones such as vinyl methyl ketone, dienes such as butadiene and isoprene, unsaturated carboxylic acids such as maleic acid and fumaric acid, and the like.

The average particle diameter of the organic fine particles constituting the inorganic / organic composite fine particles is preferably from 0.1 μm to 5.0 μm from the viewpoints of improvement in cleaning properties and stability of triboelectric charging.
In particular, it is preferably from 0.2 μm to 3.0 μm. The average particle size of the organic fine particles refers to a volume-based average particle size measured by a laser diffraction type particle size distribution analyzer “HELOS” (manufactured by SYMPATEC) equipped with a wet disperser. . However, before the measurement, a pretreatment was performed in which 10 mg of organic fine particles were dispersed in 50 ml of water together with a surfactant, and then dispersed with an ultrasonic homogenizer (output 150 W) for 1 to 10 minutes while paying attention to reaggregation due to heat generation.

The inorganic / organic composite fine particles are constituted by fixing the inorganic fine particles treated with the above-mentioned specific treatment compound on the surface of the organic fine particles. Here, the term “fixed” refers to a state in which the length of a portion of the inorganic fine particles embedded in the organic fine particles is 5% to 95%, instead of being simply attached to the organic fine particles by the electrostatic force. Such a condition
It can be confirmed by observing the surface of the inorganic / organic composite fine particles with a transmission electron microscope or a normal electron microscope. In fixing the inorganic fine particles to the surface of the organic fine particles, it is preferable to first make the organic fine particles spherical, and then to fix the inorganic fine particles to the surface of the organic fine particles.
This is because when the organic fine particles are spherical, the inorganic fine particles are uniformly fixed, and the release of the inorganic fine particles is effectively prevented. As means for spheroidizing the organic fine particles, a method in which the organic fine particles are once melted by heat and then spray granulation, a method in which the hot-melted organic fine particles are jetted into water to form a sphere, a suspension polymerization method or And a method of synthesizing spherical organic fine particles by an emulsion polymerization method.

As a means for fixing the inorganic fine particles on the surface of the organic fine particles, a method of mixing the organic fine particles and the inorganic fine particles and then applying heat, a so-called mechanochemical method of mechanically fixing the inorganic fine particles on the surface of the organic fine particles. Method is used. Specifically, the organic fine particles and the inorganic fine particles are mixed and stirred and mixed by a Henschel mixer, a V-type mixer, a turbular mixer, etc., and the inorganic fine particles are adhered to the surface of the organic fine particles by electrostatic force. A method in which the organic fine particles having the fine particles attached thereto are introduced into a heat treatment apparatus such as a nitro atomizer or a spray drier, and heat is applied to soften the surface of the organic fine particles to fix the inorganic fine particles to the surface. After attaching the inorganic fine particles, the impact-type pulverizer is modified to fix the inorganic fine particles on the surface of the organic fine particles by using a device capable of imparting mechanical energy, for example, a device such as an ang mill, a free mill, and a hybridizer. And the like.

In obtaining the inorganic / organic composite fine particles, the compounding amount of the inorganic fine particles with respect to the organic fine particles may be an amount capable of uniformly covering the surface of the organic fine particles. Specifically, although it depends on the specific gravity of the inorganic fine particles, it is usually 5 to 100% by mass, preferably 5 to 80% by mass based on the organic fine particles.
Inorganic fine particles are used in a ratio of mass%. If the proportion of the inorganic fine particles is too small, the cleaning property tends to decrease, and if the proportion of the inorganic fine particles is too large, the inorganic fine particles are easily released.

The above-mentioned inorganic / organic composite fine particles are added to and mixed with the colored particles to form a toner. The mixing ratio of the inorganic / organic composite fine particles is determined from the viewpoints of improvement in cleaning properties and stability of triboelectric charging. 0.01 to colored particles
5.0 mass% is preferable, and especially 0.01 to 2.0 mass% is preferable.

The abrasive other than the inorganic / organic composite fine particles used in the present invention will be described. Externally added abrasives include, for example, lithium titanate powder, barium titanate powder, magnesium titanate powder, strontium titanate powder, cerium oxide powder, zirconium oxide powder, titanium oxide powder, aluminum oxide powder, boron carbide powder, There are silicon carbide powder, silicon oxide powder, diamond powder and the like, and these may be used alone or in combination. Of these, strontium titanate powder and cerium oxide powder are particularly preferably used.

In the present invention, the amount of the abrasive is preferably 0.1 to 1 with respect to 100 parts by mass of the toner particles.
The amount is preferably 0.0 parts by mass, more preferably 0.2 to 5.0 parts by mass.

The binder resin constituting the electrostatic image developing toner of the present invention will be described. The binder resin, which is a component of the toner particles according to the present invention, is produced using resin particles obtained by polymerizing a polymerizable monomer in an aqueous medium.

Here, the polymerizable monomers used for producing the resin particles include styrene, o-methylstyrene, m
-Methylstyrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-phenylstyrene, p-ethylstyrene, 2,
Styrene such as 4-dimethylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene Or styrene derivatives, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, methacrylic acid Methacrylate derivatives such as lauryl, phenyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate, methyl acrylate, ethyl acrylate, isopropyl acrylate, n acrylate
-Butyl, t-butyl acrylate, isobutyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate,
Acrylate derivatives such as phenyl acrylate,
Ethylene, propylene, olefins such as isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide, vinyl fluoride, halogenated vinyls such as vinylidene fluoride, vinyl propionate, vinyl acetate, vinyl esters such as vinyl benzoate, Vinyl ethers such as vinyl methyl ether and vinyl ethyl ether; vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl hexyl ketone; N-vinyl compounds such as N-vinyl carbazole, N-vinyl indole and N-vinyl pyrrolidone; vinyl There are vinyl compounds such as naphthalene and vinylpyridine, and acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile and acrylamide. These vinyl monomers can be used alone or in combination.

Further, it is more preferable to use a polymerizable monomer constituting the resin in combination with one having an ionic dissociation group. For example, those having a substituent such as a carboxyl group, a sulfonic acid group, and a phosphate group as a constituent group of the monomer, specifically, acrylic acid, methacrylic acid,
Maleic acid, itaconic acid, cinnamic acid, fumaric acid, monoalkyl maleate, monoalkyl itaconate, styrenesulfonic acid, allylsulfosuccinic acid, 2-acrylamido-2-methylpropanesulfonic acid, acid phosphooxyethyl Methacrylate,
3-chloro-2-acid phosphooxypropyl methacrylate and the like. In addition, divinylbenzene,
Uses polyfunctional vinyls such as ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, and neopentyl glycol diacrylate. To form a crosslinked resin.

These polymerizable monomers can be polymerized using a radical polymerization initiator. In this case, an oil-soluble polymerization initiator can be used in the suspension polymerization method. As the oil-soluble polymerization initiator, 2,2'-azobis- (2,4
-Dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvalero Azo or diazo polymerization initiators such as nitrile and azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide , Dicumyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis-
Examples include peroxide-based polymerization initiators such as (4,4-t-butylperoxycyclohexyl) propane and tris- (t-butylperoxy) triazine, and polymer initiators having a peroxide in a side chain. . When an emulsion polymerization method is used, a water-soluble radical polymerization initiator can be used. Examples of the water-soluble polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetate, azobiscyanovaleric acid and salts thereof, and hydrogen peroxide.

As the dispersion stabilizer, trilithium phosphate,
Examples include magnesium phosphate, zinc phosphate, aluminum phosphate, lithium carbonate, magnesium carbonate, lithium hydroxide, magnesium hydroxide, aluminum hydroxide, lithium metasilicate, lithium sulfate, barium sulfate, bentonite, silica, and alumina. it can. Further, a surfactant generally used as a surfactant such as polyvinyl alcohol, gelatin, methyl cellulose, sodium dodecylbenzenesulfonate, ethylene oxide adduct, and higher alcohol sodium sulfate can be used as a dispersion stabilizer.

The resin excellent in the present invention preferably has a glass transition point of 20 to 90 ° C. and a softening point of 8 ° C.
The thing of 0-220 ° C is preferred. The glass transition point is measured by a differential calorimetric analysis method, and the softening point can be measured by a Koka flow tester.

Further, as these resins, in GPC (gel permeation chromatography) measurement,
Peak or shoulder at least 100,000-
It is preferably present in the range of 1,000,000 and 1,000 to 50,000, and more preferably in GPC (gel permeation chromatography) measurement, the peak or shoulder is at least 100,000 to
1,000,000 and 25,000-100,000
And between 1,000 and 25,000.

In the measurement of the above resin by GPC measurement, a chromatogram can be obtained by measuring the solution after dissolving the toner in a solvent such as THF and filtering off dust and the like.

The colorant according to the present invention will be described. The toner of the present invention is obtained by salting out / fusing the above-mentioned composite resin particles and colorant particles. Examples of the colorant (colorant particles subjected to salting out / fusion with the composite resin particles) constituting the toner of the present invention include various inorganic pigments, organic pigments, and dyes. Conventionally known inorganic pigments can be used. Specific inorganic pigments are exemplified below.

Examples of black pigments include furnace black, channel black, acetylene black,
Carbon black such as thermal black and lamp black, and magnetic powder such as magnetite and ferrite are also used.

These inorganic pigments can be used alone or in combination of two or more as desired. The amount of the pigment to be added is 2 to 20% by mass, preferably 3 to 15% by mass, based on the polymer.

When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, from the viewpoint of imparting predetermined magnetic characteristics, 20 to 1
It is preferable to add 20% by mass.

Conventionally known organic pigments and dyes can also be used. Specific examples of organic pigments and dyes are shown below.

As the pigment for magenta or red,
For example, C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I.
Pigment Red 6, C.I. I. Pigment Red 7,
C. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I. I. Pigment Red 48: 1, C.I.
I. Pigment Red 53: 1, C.I. I. Pigment Red 57: 1, C.I. I. Pigment Red 122, C.I.
I. Pigment Red 123, C.I. I. Pigment Red 139, C.I. I. Pigment red 144, C.I. I.
Pigment Red 149, C.I. I. Pigment Red 1
66, C.I. I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222
And the like.

Examples of orange or yellow pigments include C.I. I. Pigment Orange 31, C.I.
I. Pigment Orange 43, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I.
Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 9
4, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 180, C.I. I. Pigment Yellow 1
85, C.I. I. Pigment yellow 155, C.I. I. Pigment Yellow 156 and the like.

The pigments for green or cyan include:
For example, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 1
5: 3, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like.

As the dye, for example, C.I. I. Solvent Red 1, 49, 52, 58, 63
111, 122, C.I. I. Solvent Yellow 1
9, 44, 77, 79, 81, 82, 9
3, 98, 103, 104, 112, 16
2, C.I. I. Solvent Blue 25, 36, 60
70, 93, 95, etc., and mixtures thereof can also be used.

These organic pigments and dyes can be used alone or in combination of two or more as desired.
The amount of the pigment added is 2 to 20% by mass based on the polymer.
And preferably 3 to 15% by mass.

The colorant (colorant particles) constituting the toner of the present invention may be surface-modified. As the surface modifier, a conventionally known one can be used, and specifically, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent and the like can be preferably used. Examples of the silane coupling agent include alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, and diphenyldimethoxysilane, siloxanes such as hexamethyldisiloxane, γ-chloropropyltrimethoxysilane, and vinyltrimethoxysilane. Chlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
γ-ureidopropyltriethoxysilane and the like. As the titanium coupling agent, for example, TTS, 9S, 38S, 41B, 46B, 55, 138, which are commercially available under the trade name of “Plenact” manufactured by Ajinomoto Co., Inc.
S-1, 238S, etc., commercial products A-1 and B-
1, TOT, TST, TAA, TAT, TLA, TO
G, TBSTA, A-10, TBT, B-2, B-4,
B-7, B-10, TBSTA-400, TTS, TO
A-30, TSDMA, TTAB, TTOP and the like. As the aluminum coupling agent, for example,
"Plenact AL-M" manufactured by Ajinomoto Co. and the like.

The addition amount of these surface modifiers is preferably from 0.01 to 20% by mass, more preferably from 0.1 to 5% by mass, based on the colorant.

Examples of the method for modifying the surface of the colorant particles include a method in which a surface modifier is added to a dispersion of the colorant particles, and the system is heated and reacted.

The surface-modified colorant particles are collected by filtration, and are subjected to drying treatment after repeated washing and filtration with the same solvent.

The release agent used in the toner of the present invention will be described. The toner used in the present invention is preferably a toner obtained by fusing resin particles containing a release agent in an aqueous medium. In this manner, the resin particles having the release agent encapsulated in the resin particles are salted out with the colorant particles in an aqueous medium.
By fusing, a toner in which a release agent is finely dispersed can be obtained.

In the toner of the present invention, a low molecular weight polypropylene (number average molecular weight = 1500 to 900) is used as a releasing agent.
0), low molecular weight polyethylene, and the like are preferable, and an ester compound represented by the following formula is particularly preferable.

R ^1- (OCO-R ² ) _{n In the} formula, n is an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4. R ^1, R
² represents a hydrocarbon group which may have a substituent. R ¹
Has 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, and more preferably 2 to 5 carbon atoms. R ² has 1 to 40 carbon atoms, preferably 16 to 30 carbon atoms, and more preferably 18 to 26 carbon atoms.

Next, examples of typical compounds are shown below.

[0079]

Embedded image

[0080]

Embedded image

The addition amount of the above compound is 1 to 30% by mass, preferably 2 to 20% by mass, more preferably 3 to 15% by mass based on the whole toner.

The toner of the present invention is preferably prepared by encapsulating the above-described release agent in resin particles by miniemulsion polymerization, salting out and fusing with the colored particles.

The physical characteristics, number average particle diameter, variation coefficient of shape coefficient, number variation coefficient in shape and particle size distribution, shape factor and the like of the toner particles according to the present invention will be described.

The particle diameter of the toner of the present invention is preferably 2 μm to 10 μm, more preferably 2 μm to 8 μm in number average particle diameter. This particle size can be controlled by the concentration of the coagulant (salting agent), the amount of the organic solvent added, the fusing time, and the composition of the polymer in the method for producing the toner.

By adjusting the number average particle diameter to 3 to 10 μm, in the fixing step, the number of toner particles having a large adhesive force that flies and adheres to the heating member to cause offset is reduced, and the transfer efficiency is increased. As a result, the image quality of halftone is improved, and the image quality of fine lines, dots, and the like can be improved.

The number average particle diameter of the toner is determined by using a Coulter Counter TA-II, Coulter Multisizer, SLAD
It can be measured using 1100 (a laser diffraction particle size analyzer manufactured by Shimadzu Corporation) or the like.

In the present invention, a Coulter Multisizer was used, and an interface for outputting the particle size distribution (manufactured by Nikkaki Co., Ltd.) and a personal computer were connected. The particle size distribution and the average particle size were calculated by measuring the volume distribution of toner having a size of 2 μm or more (for example, 2 to 40 μm) using an aperture of 100 μm as the aperture in the Coulter Multisizer.

The shape factor of the toner particles of the present invention will be described. The shape factor of the toner of the present invention is represented by the following equation, and indicates the degree of roundness of toner particles.

Shape factor = ((maximum diameter / 2) ² × π) / projected area Here, the maximum diameter is defined as the parallel image of a projected image of a toner particle onto a plane when the image is sandwiched between two parallel lines. Means the width of the particle at which the distance between the particles becomes maximum. The projection area refers to the area of the projected image of the toner particles on the plane.

In the present invention, the shape factor can be determined by taking a photograph in which the toner particles are enlarged by a factor of 2000 using a scanning electron microscope, and referring to the photograph based on this photograph.
The measurement was performed by analyzing a photographic image using "IMAGE ANALYZER" (manufactured by JEOL Ltd.). In this case, the shape factor of the present invention was measured by using the above formula using 100 toner particles.

The variation coefficient of the shape factor of the toner according to the present invention will be described. The “coefficient of variation of the shape coefficient” of the toner is calculated from the following equation.

Coefficient of variation of toner shape coefficient = (S1 /
K) × 100 (%) In the formula, S1 represents a standard deviation of the shape factor of 100 toner particles, and K represents an average value of the shape factor.

The number particle size distribution and the number variation coefficient of the toner according to the present invention will be described. The number particle size distribution and the number variation coefficient of the toner are measured with a Coulter Counter TA-II or a Coulter Multisizer (manufactured by Coulter Inc.). In the present invention, a Coulter Multisizer was used, connected to an interface (manufactured by Nikkaki) for outputting a particle size distribution and a personal computer.

The number particle size distribution represents the relative frequency of toner particles with respect to the particle size.
It represents the median diameter in the number particle size distribution. The “number variation coefficient in the number particle size distribution” of the toner (hereinafter referred to as the “number variation coefficient of the toner”) is calculated from the following equation.

Toner number variation coefficient = (S2 / Dn) × 100 (%) In the formula, S2 represents a standard deviation in the number particle size distribution;
n indicates a number average particle size (μm).

According to a sixth aspect of the present invention, the number average particle diameter of the toner particles is 2 μm to 8 μm, the variation coefficient of the shape factor is 16% or less, and the number variation coefficient in the number particle size distribution is 27% or less. The toner of the present invention can more preferably exhibit the effects described in the present invention by adjusting to the above.

By using a toner having a variation coefficient of the shape factor of 16% or less, the effect described in the above-mentioned effect of the shape factor is more remarkably exhibited, but a more preferable variation coefficient of the shape factor is 14% or less. .

The number variation coefficient of the toner according to claim 6 is 27% or less, preferably 25% or less. When the number variation coefficient is 27% or less, the charge amount distribution becomes sharp, the transfer efficiency is increased, and the image quality is improved. When such a toner is used in the image forming apparatus of the present invention, the charging characteristics of the toner are stable, cleaning failure is unlikely to occur, and the surface of the photoconductor having the siloxane-based resin layer described above can be always kept clean. .

The method for controlling the number variation coefficient of the toner is not particularly limited. For example, a method of classifying toner particles by wind force can be used, but classification in a liquid is effective for further reducing the number variation coefficient. As a method of classifying in a liquid, there is a method of separating and collecting toner particles according to a sedimentation speed difference caused by a difference in toner particle diameter by controlling a rotation speed by using a centrifugal separator.

In particular, when a toner is produced by a suspension polymerization method, a classification operation is indispensable in order to reduce the number variation coefficient in the number particle size distribution to 27% or less. In the suspension polymerization method,
Before polymerization, it is necessary to disperse the polymerizable monomer in an aqueous medium into oil droplets of a desired size as a toner. That is, mechanical shearing by a homomixer, a homogenizer, or the like is repeated on a large oil droplet of the polymerizable monomer to reduce the oil droplet to a size of about a toner particle. In the method by a gentle shear, the number and particle size distribution of the obtained oil droplets becomes broad, and therefore,
The particle size distribution of the toner obtained by polymerizing this becomes wide. For this reason, a classification operation is required.

Further, in order to uniformly control the shape factor of the toner and the variation coefficient of the shape factor without extremely varying lots, resin particles (polymer particles) constituting the toner of the present invention are prepared (polymerized). In the step of fusing and controlling the shape of the resin particles, an appropriate process end time may be determined while monitoring the characteristics of the toner particles (colored particles) being formed.

The term "monitoring" means that a measuring device is incorporated in-line and the process conditions are controlled based on the measurement result. That is, for example, in the case of a polymerization toner formed by incorporating measurement such as shape in-line and assembling or fusing resin particles in an aqueous medium, the shape and particle size are sequentially sampled in a process such as fusing. Is measured, and the reaction is stopped when the desired shape is obtained.

Although the monitoring method is not particularly limited, a flow type particle image analyzer FPIA-
2000 (manufactured by Toa Medical Electronics Co., Ltd.) can be used. This apparatus is suitable because the shape can be monitored by performing image processing in real time while passing the sample liquid. That is, a pump or the like is used from the reaction field to constantly monitor and measure the shape and the like, and stop the reaction when the desired shape and the like are obtained.

According to a seventh aspect of the present invention, when the number average particle diameter of the toner particles is 2 μm to 8 μm and the shape coefficient is in the range of 1.0 to 1.6, the number of toner particles is at least 65% by number. And more preferably 70% by number.
That is all.

More preferably, the toner particles having a number average particle diameter of 2 μm to 8 μm and a shape coefficient in a range of 1.2 to 1.6 are 65%. % Or more, and more preferably 70% or more.

As described in the twelfth aspect, the number of toner particles having a shape factor in the range of 1.2 to 1.6 is 65% by number or more, and the variation coefficient of the shape factor is 16% or less. It has also been found that, by adjusting, excellent developability and fine line reproducibility and stable cleaning properties can be formed over a long period of time.

As for the shape coefficient, the numerical value range is 1.
When the number of toner particles in the range of 0 to 1.6 is 65% by number or more, the triboelectrification property in the developer conveying member and the like becomes more uniform, and the accumulation of excessively charged toner is eliminated.
Since the toner is more easily exchanged than the surface of the developer conveying member, problems such as a development ghost are less likely to occur. Further, the toner particles are hardly crushed, the contamination of the charging member is reduced, and effects such as stabilization of the charging property of the toner can be obtained.

The method for controlling the shape factor is not particularly limited. For example, a method of spraying toner particles into a hot air stream,
Alternatively, the shape factor may be adjusted to 1.0 to 1.6 by a method of repeatedly applying mechanical energy due to impact force in a gas phase or a method of adding a toner particle to a solvent that does not dissolve the toner to impart a swirling flow. Or 1.2-1.
There is a method of adjusting the toner of No. 6 and adding it to ordinary toner so as to fall within the range of the present invention.
Further, the whole shape is controlled at the stage of preparing a so-called polymerization toner, and the shape factor is adjusted to 1.0 to 1.6 or 1.2.
There is a method in which the toner adjusted to 1.6 is similarly added to a normal toner and adjusted.

In the toner of the present invention, when the particle diameter of the toner particles is D (μm), the natural logarithm InD is plotted on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23. In the histogram showing the standard particle size distribution, the sum of the relative frequency (m1) of the toner particles included in the most frequent class and the relative frequency (m2) of the toner particles included in the next most frequent class after the most frequent class. It is preferable that the toner has (M) of 70% or more.

When the sum (M) of the relative frequency (m1) and the relative frequency (m2) is 70% or more, the dispersion of the particle size distribution of the toner particles is narrowed. Thus, the occurrence of selective development can be reliably suppressed.

In the present invention, the histogram showing the number-based particle size distribution is obtained by dividing the natural logarithm InD (D: particle size of individual toner particles) into a plurality of classes (0 to 0) at intervals of 0.23.
0.23: 0.23 to 0.46: 0.46 to 0.69:
0.69 to 0.92: 0.92 to 1.15: 1.15
1.38: 1.38 to 1.61: 1.61 to 1.84:
1.84 to 2.07: 2.07 to 2.30: 2.30 to
2.53: a histogram showing the number-based particle size distribution divided into 2.53 to 2.76..., Which is a particle size data of a sample measured by a Coulter Multisizer according to the following conditions. Is transferred to a computer via an I / O unit, and the computer creates the program using a particle size distribution analysis program.

[Measurement conditions] 1: Aperture: 100 μm 2: Sample preparation method: Electrolyte [ISOTON R-11
(Coulter Scientific Japan) 5
An appropriate amount of a surfactant (neutral detergent) is added to 0 to 100 ml and stirred, and 10 to 20 mg of a measurement sample is added thereto. This system is prepared by subjecting it to a dispersion treatment with an ultrasonic disperser for 1 minute.

Further, the inventors of the present invention have focused on the minute shape of each toner particle, and as a result, the shape of the corner portion of the toner particle has changed inside the developing device, and the shape has become round. It was found that blade wear occurred. Although the reason for this is not clear, it is presumed that stress is likely to be applied to the corner portion, which promotes blade wear in this portion. In addition, when electric charge is applied to the toner particles by frictional charging, it is presumed that the electric charge tends to be concentrated particularly in the corner portions, and the electric charge of the toner particles tends to be uneven.

That is, the ratio of toner particles having no corners is 50% by number or more, and the number variation coefficient in the number particle size distribution is 2%.
It has also been found that by using a toner composed of toner particles controlled to 7% or less, it is possible to form a high-quality image over a long period of time with excellent developability and fine line reproducibility.

The “cornerless toner particles” according to the present invention will be described with reference to FIG. In the toner according to the present invention, the ratio of the toner particles having no corners in the toner particles constituting the toner is preferably 50% by number or more, more preferably 70% by number or more.

When the ratio of the toner particles having no corners is 50% by number or more, the gap of the transferred toner layer (powder layer) is reduced, the fixing property is improved, and the offset hardly occurs. In addition, the amount of toner particles that are easily worn or broken and the number of toner particles having a portion where charges are concentrated are reduced, the charge amount distribution becomes sharp, the chargeability is stabilized, and good image quality can be formed over a long period of time.

Here, “toner particles having no corners” refers to toner particles having substantially no protrusions where charges are concentrated or which are easily worn out by stress.
Specifically, the following toner particles are referred to as toner particles having no corners. That is, as shown in FIG.
When the major axis is L, a circle C having a radius (L / 10)
The case where the circle C does not substantially protrude outside the toner T when the inside is rolled while contacting the inside at one point with respect to the peripheral line of the toner particle T is referred to as “toner particle having no corner”. “Cases that do not substantially protrude” refer to cases where there are no more than one protrusion having a protruding circle. Also,
The “longer diameter of the toner particle” refers to the width of the particle at which the interval between the parallel lines is the largest when the projected image of the toner particle on the plane is sandwiched between two parallel lines. FIGS. 5B and 5C show projected images of toner particles having corners, respectively.

The ratio of the toner particles having no corners was measured as follows. First, a photograph in which the toner particles were enlarged by a scanning electron microscope was taken, and further enlarged to 15.0.
Obtain a 00x photographic image. Next, the presence or absence of the corners is measured for this photographic image. This measurement was performed for 100 toner particles.

The method for obtaining a toner having no corners is not particularly limited. For example, as described above, as a method of controlling the shape coefficient, a method of spraying toner particles into a hot air flow, a method of repeatedly applying mechanical energy by an impact force in a gas phase, or a method of dissolving a toner It can be obtained by adding to a solvent that does not contain and giving a swirling flow.

A method for producing the toner of the present invention will be described. The toner of the present invention is prepared by suspension polymerization or emulsion polymerization of a monomer in a liquid containing an emulsion of necessary additives (in an aqueous medium) or miniemulsion polymerization to prepare fine resin particles. Then, the charge controllable resin particles of the present invention are added, and thereafter, an organic solvent, a coagulant such as a salt or the like is added, and the resin particles can be coagulated and fused.

An example of a method for producing the toner of the present invention is as follows. A charge controlling resin is dissolved in a polymerizable monomer, and a colorant, a releasing agent as necessary, and a polymerization initiator. The constituent materials are added, and various constituent materials are dissolved or dispersed in the polymerizable monomer using a homogenizer, a sand mill, a sand grinder, an ultrasonic disperser, or the like. The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in an aqueous medium containing a dispersion stabilizer into oil droplets of a desired size as a toner using a homomixer, a homogenizer, or the like. Thereafter, the stirring mechanism is moved to a reaction device (stirring device), which is a stirring blade described later, and the polymerization reaction is advanced by heating. After completion of the reaction, the toner of the present invention is prepared by removing the dispersion stabilizer, filtering, washing and drying.
The “aqueous medium” in the present invention means a medium containing at least 50% by mass of water.

Further, as a method of producing the toner of the present invention, a method of preparing a resin particle by salting out, aggregating, and fusing in an aqueous medium can also be mentioned. This method is not particularly limited.
No. 5,252, JP-A-6-329947, and JP-A-9-15904. That is, a method of salting out, aggregating, and fusing a plurality of fine particles composed of a resin and a colorant, or a dispersion particle of a constituent material such as a resin particle and a colorant, particularly dispersing these in water using an emulsifier. After that, a coagulant having a critical coagulation concentration or more is added and salted out, and at the same time, the formed polymer itself is heated and fused at a temperature of the glass transition temperature or more to gradually grow the particle size while forming fused particles. When the target particle size is reached, add a large amount of water to stop the particle size growth, further heat and stir to smooth the particle surface to control the shape, and heat the particles in a fluid state while keeping the particles wet. By drying, the toner of the present invention can be formed. Here, a solvent such as alcohol which is infinitely soluble in water may be added together with the coagulant.

The toner manufacturing process mainly includes the following steps. 1: Area where the release agent is other than the outermost layer (center or middle layer)
Multi-stage polymerization step (I) for obtaining composite resin particles contained in (2): salting-out / fusion step (II) in which the composite resin particles and colorant particles are subjected to salting-out / fusion to obtain toner particles : Filtering the toner particles from the dispersion system of the toner particles,
A filtration / washing step of removing a surfactant or the like from the toner particles; a drying step of drying the washed toner particles; and a step of adding an external additive to the dried toner particles.

Hereinafter, each step will be described in detail. [Multi-stage polymerization step (I)] The multi-stage polymerization step (I) is a step of producing composite resin particles by a multi-stage polymerization method in which a coating layer made of a monomer polymer is formed on the surface of the resin particles.

In the present invention, it is preferable to employ a multi-stage polymerization method of three-stage polymerization or more from the viewpoints of production stability and crushing strength of the obtained toner.

The two-stage polymerization method and the three-stage polymerization method, which are typical examples of the multi-stage polymerization method, will be described below.

<Two-Step Polymerization Method> The two-step polymerization method comprises a central portion (nucleus) formed of a high molecular weight resin containing a release agent and an outer layer (shell) formed of a low molecular weight resin. This is a method for producing composite resin particles.

More specifically, this method will be described. First, a release agent is dissolved in a monomer L to prepare a monomer solution, and this monomer solution is added to an aqueous medium (for example, an aqueous solution of a surfactant). After oil droplets are dispersed in the system, this system is subjected to polymerization treatment (first stage polymerization).
By doing so, a dispersion of high molecular weight resin particles containing a release agent is prepared.

Next, a polymerization initiator and a monomer L for obtaining a low-molecular-weight resin were added to the dispersion of the resin particles.
Polymerization treatment of monomer L in the presence of resin particles (second stage polymerization)
Is carried out to form a coating layer made of a low-molecular-weight resin (polymer of monomer L) on the surface of the resin particles.

<Three-step polymerization method> The three-step polymerization method comprises a central part (nucleus) formed from a high molecular weight resin, an intermediate layer containing a release agent, and an outer layer (shell) formed from a low molecular weight resin. This is a method for producing composite resin particles.

The method will be described in detail. First, a dispersion of resin particles obtained by a polymerization treatment (first-stage polymerization) according to a conventional method is added to an aqueous medium (for example, an aqueous solution of a surfactant). Along with the addition, the monomer solution obtained by dissolving the release agent in the monomer M in the aqueous medium is dispersed in oil droplets, and then the system is subjected to a polymerization treatment (second stage polymerization).
A coating layer (intermediate layer) made of a resin (polymer of monomer M) containing a release agent is formed on the surface of the resin particles (core particles) to form a composite resin particle (high molecular weight resin-intermediate molecular weight resin). )
A dispersion of is prepared.

Next, a polymerization initiator and a monomer L for obtaining a low-molecular-weight resin are added to the resulting dispersion of the composite resin particles, and the monomer L is subjected to a polymerization treatment in the presence of the composite resin particles. By performing (third stage polymerization), a coating layer made of a low molecular weight resin (polymer of monomer L) is formed on the surfaces of the composite resin particles. In the above method, by incorporating the second-stage polymerization, the release agent can be finely and uniformly dispersed, which is preferable.

One feature of the method for producing a toner according to the present invention is to polymerize a polymerizable monomer in an aqueous medium. That is, when forming resin particles (core particles) or a coating layer (intermediate layer) containing a release agent, the release agent is dissolved in a monomer, and the resulting monomer solution is oiled in an aqueous medium. In this method, latex particles are obtained by dispersing droplets, adding a polymerization initiator to the system, and performing a polymerization treatment.

In the present invention, the aqueous medium refers to water 50 to 10
A medium comprising 0% by mass and 0 to 50% by mass of a water-soluble organic solvent. Examples of the water-soluble organic solvent include, for example, methanol, ethanol, isopropanol, butanol,
Acetone, methyl ethyl ketone, tetrahydrofuran and the like can be exemplified, and an alcohol-based organic solvent which does not dissolve the obtained resin is preferable.

As a polymerization method suitable for forming a resin particle or a coating layer containing a release agent, an aqueous medium in which a surfactant having a concentration equal to or lower than the critical micelle concentration is dissolved is used.
A monomer solution in which the release agent is dissolved in the monomer is dispersed in oil droplets using mechanical energy to prepare a dispersion, and a water-soluble polymerization initiator is added to the obtained dispersion, A method in which radical polymerization is carried out in oil droplets (hereinafter, referred to as “mini-emulsion method” in the present invention) can be mentioned, and the effect of the present invention can be further exhibited, which is preferable. In the above method, an oil-soluble polymerization initiator may be used instead of or together with the water-soluble polymerization initiator.

According to the mini-emulsion method in which oil droplets are formed mechanically, unlike the usual emulsion polymerization method, the release agent dissolved in the oil phase does not detach, and the resin particles or A sufficient amount of release agent can be introduced into the coating layer.

Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited. For example, a stirrer “CLEARMIX” (M -Technic Co., Ltd.), an ultrasonic disperser, a mechanical homogenizer, a Menton-Gaulin and a pressure homogenizer. Further, the dispersion particle diameter is 1
0 to 1000 nm, preferably 50 to 1000 n
m, more preferably 30 to 300 nm.

As other polymerization methods for forming the resin particles or the coating layer containing the release agent, emulsion polymerization methods,
Known methods such as a suspension polymerization method and a seed polymerization method can also be employed. In addition, these polymerization methods are resin particles (core particles) or coating layers constituting the composite resin particles,
It can also be employed to obtain one that does not contain a release agent.

The particle size of the composite resin particles obtained in the polymerization step (I) is determined by using an electrophoretic light scattering photometer “ELS-80”.
It is preferable that the weight average particle diameter measured using “0” (manufactured by Otsuka Electronics Co., Ltd.) is in the range of 10 to 1000 nm.

In addition, the glass transition temperature (T
g) is preferably in the range of 48 to 74 ° C, more preferably 52 to 64 ° C.

The softening point of the composite resin particles is 95-14.
It is preferably in the range of 0 ° C. [Salt-out / fusion step (II)] This salt-out / fusion step (II)
Is an amorphous (non-spherical) by salting out / fusing the composite resin particles and the colorant particles obtained in the multi-stage polymerization step (I) (simultaneous salting out and fusion).
This is the step of obtaining the toner particles.

In the present invention, salting out / fusion refers to simultaneous salting out (aggregation of particles) and fusion (disappearance of interfaces between particles) or simultaneous salting out and fusion. Act. In order to simultaneously carry out the salting-out and the fusion, the particles (composite resin particles, colorant particles) under a temperature condition not lower than the glass transition temperature (Tg) of the resin constituting the composite resin particles.
Need to be aggregated.

In the salting-out / fusion step (II), together with the composite resin particles and the colorant particles, internal additive particles (fine particles having a number average primary particle diameter of about 10 to 1000 nm) such as a charge controlling agent are salted out. / It may be fused. The colorant particles may be surface-modified, and as the surface modifier,
Conventionally known ones can be used.

The colorant particles are subjected to salting out / fusion treatment in a state of being dispersed in an aqueous medium. The aqueous medium in which the colorant particles are dispersed is preferably an aqueous solution in which a surfactant is dissolved at a concentration equal to or higher than the critical micelle concentration (CMC).

The disperser used for the dispersion treatment of the colorant particles is not particularly limited, but is preferably a stirrer “CLEARMIX (CLEARM) equipped with a high-speed rotating rotor.
MIX) "(manufactured by M Technique Co., Ltd.), an ultrasonic disperser, a pressurized disperser such as a mechanical homogenizer, a Menton-Gaulin, a pressure type homogenizer, and a medium disperser such as a Getzman mill or a diamond fine mill.

In order to salt out / fuse the composite resin particles and the colorant particles, a salting-out agent (aggregating agent) having a critical coagulation concentration or more is added to the dispersion in which the composite resin particles and the colorant particles are dispersed. ) And heating the dispersion above the glass transition temperature (Tg) of the composite resin particles.

The preferable temperature range for salting out / fusing is (Tg + 10) to (Tg + 50 ° C.), and particularly preferably (Tg + 15) to (Tg + 40 ° C.). Further, in order to effectively perform the fusion, an organic solvent which is infinitely soluble in water may be added.

[Filtration / Washing Step] In this filtration / washing step, a filtration treatment for filtering the toner particles from the dispersion system of the toner particles obtained in the above step and a filtration treatment for the toner particles (cake-like) are performed. Washing treatment for removing extraneous substances such as surfactants and salting-out agents from the aggregates).

The filtration method is not particularly limited, such as a centrifugal separation method, a reduced pressure filtration method using a Nutsche method, and a filtration method using a filter press.

[Drying Step] This step is a step of drying the washed toner particles.

[0151] Examples of the dryer used in this step include a spray dryer, a vacuum freeze dryer, and a reduced-pressure dryer. A stationary shelf dryer, a movable shelf dryer, a fluidized bed dryer, a rotary bed dryer, It is preferable to use a type dryer, a stirring type dryer and the like.

The water content of the dried toner particles is preferably 5% by mass or less, more preferably 2% by mass or less.

Further, in producing the toner for developing an electrostatic image according to the present invention, particles are formed in an aqueous medium as described above, and after drying the particles, the fatty acid lithium salt according to the present invention is added to 0.1%. External addition in the range of 005% by mass to 0.3% by mass produces toner particles.

Incidentally, the dried toner particles are
In the case where the aggregates are aggregated by a weak attraction between particles, the aggregates may be crushed. Here, as the crushing device,
A mechanical pulverizer such as a jet mill, a Henschel mixer, a coffee mill, and a food processor can be used.

The toner of the present invention forms composite resin particles in the absence of a colorant, and adds a dispersion of the colorant particles to a dispersion of the composite resin particles to form the composite resin particles and the colorant particles. It is preferably prepared by salting out / fusing.

As described above, by preparing the composite resin particles in a system in which no colorant is present, the polymerization reaction for obtaining the composite resin particles is not hindered. Therefore, according to the toner of the present invention, the excellent offset resistance is not impaired, and the fixing device is not stained or the image is not stained due to the accumulation of the toner.

In addition, as a result of the reliable polymerization reaction for obtaining the composite resin particles, no monomer or oligomer remains in the obtained toner particles. No unpleasant odor is generated in the heat fixing step.

Further, the surface characteristics of the obtained toner particles are uniform and the charge amount distribution becomes sharp, so that an image having excellent sharpness can be formed for a long period of time. According to such a toner having a uniform composition, molecular weight, and surface characteristics among toner particles, good adhesion (high fixing strength) to an image support is maintained in an image forming apparatus including a fixing step by a contact heating method. Meanwhile, the offset resistance and the anti-winding property can be improved, and an image having an appropriate gloss can be obtained.

Next, each component used in the toner manufacturing process will be described in detail. (Polymerizable monomer) As a polymerizable monomer for producing the resin (binder) used in the present invention, a hydrophobic monomer is an essential component, and a crosslinkable monomer is optionally used. Used. As described below, at least one monomer having an acidic polar group or a monomer having a basic polar group is used.
It is desirable to contain a kind.

(1) Hydrophobic monomer The hydrophobic monomer constituting the monomer component is not particularly limited, and a conventionally known monomer can be used. Further, one kind or a combination of two or more kinds can be used so as to satisfy required characteristics.

Specifically, a monovinyl aromatic monomer,
It is possible to use (meth) acrylate monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers, halogenated olefin monomers, and the like. it can.

Examples of the vinyl aromatic monomer include, for example,
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n- Styrene-based monomers such as octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof. .

The acrylic monomers include acrylic acid,
Methacrylic acid, methyl acrylate, ethyl acrylate,
Butyl acrylate, 2-ethylhexyl acrylate,
Cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, β-hydroxyethyl acrylate, γ-aminopropyl acrylate, stearyl methacrylate, methacryl Dimethylaminoethyl acrylate, diethylaminoethyl methacrylate and the like.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, vinyl benzoate and the like.

Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like.

Examples of the monoolefin-based monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene and the like.

Examples of the diolefin-based monomer include butadiene, isoprene, chloroprene and the like.

(2) Crosslinkable monomer A crosslinkable monomer may be added to improve the properties of the resin particles. Examples of the crosslinkable monomer include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.

(3) Monomer having an acidic polar group Examples of the monomer having an acidic polar group include (a) an α, β-ethylenically unsaturated compound having a carboxyl group (—COOH) and (b) a sulfone. Α, β-ethylenically unsaturated compounds having a group (—SO ₃ H) can be mentioned.

Examples of the (a) α, β-ethylenically unsaturated compound having a —COO group include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, and monobutyl maleate. Examples thereof include esters, monooctyl maleate, and metal salts of Na, Zn and the like.

Examples of the (b) α, β-ethylenically unsaturated compound having a —SO ₃ H group include sulfonated styrene, its Na salt, allyl sulfosuccinic acid, allyl sulfosuccinate octyl, its Na salt and the like. be able to.

(4) Monomer having a basic polar group Examples of the monomer having a basic polar group include (i) an amine group or a quaternary ammonium group having 1 to 1 carbon atoms.
2, preferably 2 to 8, particularly preferably 2, (meth) acrylic esters of aliphatic alcohols, (ii) (meth)
Acrylamide or optionally N-C18
(Meth) acrylic acid amide mono- or di-substituted with an alkyl group, (iii) a vinyl compound substituted with a heterocyclic group having N as a ring member, and (iv) N, N-diallyl-
Examples thereof include an alkylamine and a quaternary ammonium salt thereof. Among them, (i) the (meth) acrylic acid ester of an aliphatic alcohol having an amine group or a quaternary ammonium group is preferable as the monomer having a basic polar group.

Examples of the (meth) acrylate of an aliphatic alcohol having an amine group or a quaternary ammonium group (i) include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, Quaternary ammonium salts of four compounds, 3-dimethylaminophenyl acrylate, 2-hydroxy-
Examples thereof include 3-methacryloxypropyltrimethylammonium salt.

Examples of (ii) (meth) acrylamide or (meth) acrylamide optionally mono- or dialkyl-substituted on N include acrylamide, N-butylacrylamide, N, N-dibutylacrylamide, piperidylacrylamide, Methacrylamide, N-butyl methacrylamide, N, N-dimethylacrylamide,
N-octadecylacrylamide and the like can be mentioned.

Examples of the vinyl compound (iii) substituted with a heterocyclic group having N as a ring member include vinylpyridine,
Vinyl pyrrolidone, vinyl-N-methylpyridinium chloride, vinyl-N-ethylpyridinium chloride and the like can be mentioned.

Examples of (iv) N, N-diallyl-alkylamine include N, N-diallylmethylammonium chloride, N, N-diallylethylammonium chloride and the like.

(Polymerization Initiator) The radical polymerization initiator used in the present invention can be appropriately used as long as it is water-soluble. For example, persulfates (eg, potassium persulfate, ammonium persulfate, etc.), azo compounds (eg, 4,4 ′)
-Azobis-4-cyanovaleric acid and salts thereof, 2,2'-azobis (2-amidinopropane) salts and the like), peroxide compounds and the like. Further, the above radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. The use of a redox initiator is preferable because the polymerization activity is increased, the polymerization temperature can be reduced, and the polymerization time can be further shortened.

As the polymerization temperature, any temperature may be selected as long as it is equal to or higher than the minimum radical generation temperature of the polymerization initiator. For example, a temperature in the range of 50 to 90 ° C. is used. However, by using a polymerization initiator started at room temperature, for example, a combination of hydrogen peroxide and a reducing agent (such as ascorbic acid), polymerization can be performed at room temperature or higher.

(Chain Transfer Agent) For the purpose of adjusting the molecular weight, a known chain transfer agent can be used. The chain transfer agent is not particularly limited, for example, octyl mercaptan, dodecyl mercaptan,
A compound having a mercapto group such as tert-dodecyl mercaptan is used. In particular, a compound having a mercapto group is preferably used because it suppresses odor at the time of heating and fixing, and a toner having a sharp molecular weight distribution is obtained, and has excellent storage stability, fixing strength, and offset resistance. For example, ethyl thioglycolate, propyl thioglycolate, propyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate And compounds having a mercapto group of ethylene glycol, compounds having a mercapto group of neopentyl glycol, and compounds having a mercapto group of pentaerythritol. Among them, n-octyl-3-mercaptopropionate is particularly preferable from the viewpoint of suppressing odor during toner heat fixing.

(Surfactant) In order to carry out miniemulsion polymerization using the above-mentioned polymerizable monomer, it is preferable to disperse oil droplets in an aqueous medium using a surfactant. Surfactants that can be used at this time are not particularly limited, but the following ionic surfactants can be mentioned as examples of suitable compounds.

Examples of the ionic surfactant include sulfonates (sodium dodecylbenzenesulfonate,
Sodium arylalkyl polyether sulfonate,
3,3-disulfonediphenylurea-4,4-diazo-
Sodium bis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol -6
Sodium sulfonate), sulfate salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.),
Fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, lithium oleate, etc.) can be mentioned.

Further, nonionic surfactants can also be used. Specifically, for example, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, esters of polyethylene glycol and higher fatty acids, alkylphenol polyethylene oxide, esters of higher fatty acids and polyethylene glycol, esters of higher fatty acids and polypropylene oxide, And sorbitan esters.

In the present invention, these surfactants are mainly used as an emulsifier at the time of emulsion polymerization, but they may be used for other steps or other purposes.

The resin particles used in the toner of the present invention and the molecular weight distribution of the toner of the present invention having the resin particles as a constituent will be described.

The toner of the present invention has a peak or shoulder of 10
000-1,000,000, and 1,000-
Preferably, the peak or shoulder is between 100,000 and 1,000,000,
5,000 to 150,000 and 1,000 to 50,000
More preferably it is present at 00.

The molecular weight of the resin particles is from 100,000 to
A resin containing at least a high molecular weight component having a peak or shoulder in the region of 1,000,000 and a low molecular weight component having a peak or shoulder in the region of 1,000 to less than 50,000 is preferred. More preferably, it is preferable to use an intermediate molecular weight resin having a peak or shoulder at a peak molecular weight of 15,000 to 100,000.

The method for measuring the molecular weight of toner or resin is as follows.
The measurement is preferably performed by GPC (gel permeation chromatography) using THF (tetrahydrofuran) as a solvent. That is, 1.0 ml of THF is added to 0.5 to 5 mg, more specifically, 1 mg of a measurement sample, and the mixture is stirred at room temperature using a magnetic stirrer or the like to be sufficiently dissolved. Then, pore size 0.45 to 0.50
After treating with a μm membrane filter, the mixture is injected into GPC. The GPC measurement conditions were as follows: the column was stabilized at 40 ° C., THF was flowed at a flow rate of 1.0 ml per minute, and 1 m
Approximately 100 μl of a sample at a concentration of g / ml is injected and measured. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex GPC KF-801, 802, 8 manufactured by Showa Denko KK
03, 804, 805, 806, 807, TSKgelG1000H, G2000H, manufactured by Tosoh Corporation,
G3000H, G4000H, G5000H, G600
0H, G7000H, TSKguard column
And the like. As the detector, a refractive index detector (IR detector) or a UV detector may be used. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodispersed polystyrene standard particles. It is preferable to use about 10 polystyrenes for preparing a calibration curve.

The coagulant used when preparing the toner particles of the present invention will be described. The coagulant used in the present invention is preferably selected from metal salts.

Examples of the metal salt include salts of monovalent metals such as alkali metals such as sodium, potassium and lithium, salts of divalent metals such as alkaline earth metals such as lithium and magnesium, and salts of manganese and copper. And trivalent metal salts such as iron and aluminum.

Specific examples of these metal salts are shown below.
Specific examples of metal salts of monovalent metals include sodium chloride,
Potassium chloride, lithium chloride, and metal salts of divalent metals include lithium chloride, zinc chloride, copper sulfate, magnesium sulfate, and manganese sulfate. Examples of the trivalent metal salt include aluminum chloride and iron chloride. These are appropriately selected according to the purpose. In general, the divalent metal salt has a smaller critical aggregation concentration (coagulation value or coagulation point) than the monovalent metal salt, and the trivalent metal salt has a smaller critical aggregation concentration.

The critical aggregation concentration referred to in the present invention is an index relating to the stability of a dispersion in an aqueous dispersion, and indicates the concentration at which aggregation occurs when a coagulant is added. This critical aggregation concentration varies greatly depending on the latex itself and the dispersant. For example, Seizo Okamura et al., Polymer Chemistry 17,601
(1960), and according to these descriptions, the value can be known. Also, as another method,
It is also possible to add a desired salt to the target particle dispersion at a different concentration, measure the ζ potential of the dispersion, and determine the salt concentration at the point where the ζ potential changes to be the critical aggregation concentration.

In the present invention, the polymer fine particle dispersion is treated using a metal salt so as to have a concentration higher than the critical aggregation concentration. At this time, of course, add the metal salt directly,
The addition as an aqueous solution is arbitrarily selected depending on the purpose. In the case of adding as an aqueous solution, the added metal salt needs to be at or above the critical aggregation concentration of the polymer particles with respect to the volume of the polymer particle dispersion and the total volume of the metal salt aqueous solution.

The concentration of the metal salt as the coagulant in the present invention may be at least the critical coagulation concentration, but is preferably added at least 1.2 times, more preferably at least 1.5 times the critical coagulation concentration.

In the present invention, from the viewpoint of suppressing excessive charging of the toner particles and imparting a uniform charging property, in particular, in order to stabilize and maintain the charging property with respect to the environment, the electrostatic charge image of the present invention is used. The toner for development preferably contains 250 to 20,000 ppm, more preferably 800 to 5,000 ppm, of the above-mentioned metal element (forms include metals and metal ions) in the toner.

In the present invention, the total value of the divalent (trivalent) metal element used for the coagulant and the monovalent metal element added as the coagulation terminator described later is 350 to 35,000 pp.
m is preferable.

The amount of metal ions remaining in the toner is measured using a fluorescent X-ray analyzer “System 3270” (manufactured by Rigaku Denki Kogyo Co., Ltd.) using a metal species of a metal salt used as a coagulant (for example, (E.g., calcium derived from calcium chloride). As a specific measuring method, a plurality of toners having a known content ratio of the coagulant metal salt are prepared, 5 g of each toner is pelletized, and the content ratio of the coagulant metal salt (mass p
pm) and the relationship (calibration curve) between the fluorescent X-ray intensity (peak intensity) from the metal species of the metal salt is measured. Next, the toner (sample) whose content ratio of the coagulant metal salt is to be measured is similarly pelletized, and the fluorescence X from the metal species of the coagulant metal salt is determined.
By measuring the linear intensity, the content ratio, that is, the “remaining amount of metal ions in the toner” can be obtained.

The developer used in the present invention will be described. The toner of the present invention may be used as a one-component developer or a two-component developer.

When used as a one-component developer, a non-magnetic one-component developer or 0.1 to 0.5 μm
And a magnetic one-component developer containing a certain amount of magnetic particles, and any of them can be used.

Further, it can be used as a two-component developer by mixing with a carrier. In this case, as magnetic particles of the carrier, metals such as iron, ferrite and magnetite,
Conventionally known materials such as alloys of these metals with metals such as aluminum and lead can be used. Particularly, ferrite particles are preferable. The magnetic particles have a volume average particle size of 15 to 100 μm, more preferably 25 to 8 μm.
It is preferably 0 μm.

The volume average particle size of the carrier is typically measured by a laser diffraction type particle size distribution analyzer “HELOS” equipped with a wet disperser (SYMPATIC (SYMPIC)).
(ATEC)).

The carrier is preferably a carrier in which magnetic particles are further coated with a resin, or a so-called resin-dispersed carrier in which magnetic particles are dispersed in a resin. The resin composition for coating is not particularly limited, but, for example, an olefin resin, a styrene resin, a styrene-acrylic resin, a silicone resin, an ester resin, or a fluorine-containing polymer resin is used. The resin for forming the resin dispersion type carrier is not particularly limited, and a known resin can be used. For example, a styrene-acrylic resin, a polyester resin, a fluororesin, a phenol resin, or the like is used. be able to.

The image forming apparatus used in the present invention will be described. The toner of the present invention is suitably used in an image forming apparatus including a step of fixing an image forming support on which a toner image is formed by passing the image forming support between a heating roller and a pressure roller constituting a fixing device. .

FIG. 1 is a sectional view showing an example of a fixing device using the toner of the present invention. The fixing device shown in FIG. 1 includes a heating roller 10 and a pressure roller 20 which comes into contact with the heating roller 10. . In FIG. 1, T is a toner image formed on a transfer paper (image forming support).

[0204] The heating roller 10 has a coating layer 12 made of a fluororesin or an elastic body formed on the surface of a metal core 11, and includes a heating member 13 made of a linear heater.

The core metal 11 is made of metal and has an inner diameter of 10 to 70 mm. The metal constituting the metal core 11 is not particularly limited, but examples thereof include metals such as iron, aluminum and copper or alloys thereof.

The thickness of the core metal 11 is set to 0.1 to 15 mm, and is determined in consideration of a balance between a demand for energy saving (thinning) and a strength (depending on a constituent material). For example,
In order to maintain a strength equivalent to that of a 0.57 mm iron core with an aluminum core, the wall thickness must be 0.8 mm.

As the fluororesin constituting the coating layer 12, PTFE (polytetrafluoroethylene) and P
FA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) and the like can be exemplified.

The thickness of the coating layer 12 made of fluororesin is 1
It is 0-500 μm, preferably 20-400 μm.

The thickness of the coating layer 12 made of fluororesin is 1
When the thickness is less than 0 μm, the function as a coating layer cannot be sufficiently exhibited, and the durability as a fixing device cannot be secured. On the other hand, there is a problem that the surface of the coating layer having a thickness of more than 500 μm is easily scratched by paper dust, and toner or the like adheres to the scratched portion, thereby causing image stains. Further, as the elastic body constituting the coating layer 12, it is preferable to use silicone rubber and silicone sponge rubber having good heat resistance such as LTV, RTV, and HTV.

Elastic Asker C constituting the coating layer 12
The hardness is less than 80 °, preferably less than 60 °. The thickness of the coating layer 12 made of an elastic material is 0.1
３０30 mm, preferably 0.1-20 mm.

The elastic material Asker C constituting the coating layer 12
When the hardness exceeds 80 ° and when the thickness of the coating layer 12 is less than 0.1 mm, the nip for fixing cannot be increased, and the effect of soft fixing (for example, the smoothed interface Improvement effect of color reproducibility by toner layer)
Cannot be demonstrated.

[0212] As the heating member 13, a halogen heater can be suitably used. The pressure roller 20
A coating layer 22 made of an elastic body is formed on the surface of the core metal 21. The elastic body constituting the coating layer 22 is not particularly limited, and examples thereof include various soft rubbers such as urethane rubber and silicone rubber and sponge rubber, and the silicone rubber exemplified as the material constituting the coating layer 12 and the like. It is preferable to use silicone sponge rubber.

Elastic Asker C constituting the coating layer 22
The hardness is less than 80 °, preferably less than 70 °, more preferably less than 60 °.

The thickness of the coating layer 22 is 0.1 to 30 m.
m, and preferably 0.1 to 20 mm.

Elastic Asker C constituting the coating layer 22
When the hardness exceeds 80 ° and when the thickness of the coating layer 22 is less than 0.1 mm, the nip for fixing cannot be increased, and the effect of soft fixing cannot be exhibited.

The material constituting the core 21 is not particularly limited, but may be a metal such as aluminum, iron, copper or the like, or an alloy thereof.

The contact load (total load) between the heating roller 10 and the pressure roller 20 is usually 40 to 350 N, preferably 50 to 300 N, and more preferably 50 to 300 N.
２５０250N. This contact load is applied to the heating roller 1
It is defined in consideration of the strength of 0 (thickness of the metal core 11). For example, in the case of a heating roller having a metal core of 0.3 mm, it is preferably 250 N or less.

From the viewpoints of offset resistance and fixability, the nip width is preferably 4 to 10 mm, and the surface pressure of the nip is 0.6 × 10 ⁵ Pa to 1.5.
It is preferably × 10 ⁵ Pa.

An example of the fixing conditions by the fixing device shown in FIG. 1 is as follows. Fixing temperature (surface temperature of heating roller 10)
Is 150 to 210 ° C., and the fixing linear velocity is 80 to 640 m.
m / sec.

The fixing device used in the present invention may be provided with a cleaning mechanism as required. In this case, as a method of supplying the silicone oil to the upper roller (heating roller) of the fixing unit, a method of supplying and cleaning with a pad, a roller, a web, or the like impregnated with the silicone oil can be used.

As the silicone oil, those having high heat resistance are used, and polydimethyl silicone, polyphenylmethyl silicone, polydiphenyl silicone and the like are used. Since those having a low viscosity have a large outflow during use, those having a viscosity at 20 ° C. of 1 to 100 Pa · s are preferably used.

However, the effect of the present invention is particularly remarkably exhibited when an image is formed by using a fixing device that does not supply silicone oil or that supplies a very small amount of silicone oil. Therefore, even when the silicone oil is supplied, the supply amount is preferably 2 mg or less per A4 sheet.

By setting the supply amount of the silicone oil to 2 mg or less per A4 sheet, the amount of the silicone oil adhering to the transfer paper (image support) after fixing is reduced, and the ballpoint pen is formed by the silicone oil adhering to the transfer paper. There is no difficulty in writing with an oil-based pen, etc., and the writing performance is not impaired.

In addition, it is possible to avoid problems such as deterioration of the offset resistance with time due to deterioration of the silicone oil, and contamination of the optical system and the band electrode by the silicone oil.

Here, the supply amount of the silicone oil is set to the transfer paper (A) in the fixing device (between the rollers) heated to a predetermined temperature.
100 sheets of 4 size white paper) are continuously passed, and the mass change (Δw) of the fixing device before and after the paper passing is measured and calculated (Δw / 100).

A cleaning blade used in an image forming apparatus according to the present invention will be described. The cleaning blade used in the present invention is preferably an elastic rubber blade. The physical properties of the cleaning blade are controlled simultaneously by controlling the rubber hardness and the rebound resilience, whereby the torque fluctuation of the present invention can be controlled to be small, and the reversal of the blade can be suppressed more effectively. 25 ± 5
When the JIS A hardness of the blade at less than 65 ° C. is less than 65, the blade is likely to be inverted, and when it is more than 80, the cleaning performance is reduced. Also, if the rebound resilience exceeds 80, the blade is likely to be inverted,
If it is less than 20, the cleaning performance deteriorates. More preferable rebound resilience is 20 or more and 80 or less. Young's modulus is 2
Those having a range of 94 to 588 N / cm ² are preferable. (J
Both ISA hardness and rebound resilience are measured based on the vulcanized rubber physical test method of JIS K6301. The value of the rebound resilience indicates%. Urethane rubber, silicon rubber, fluorine rubber, chloropyrene rubber, butadiene rubber, and the like are known as the material of the elastic rubber blade used for the cleaning blade. Among them, urethane rubber is compared with other rubbers. It is particularly preferable in that it has excellent wear characteristics. For example, urethane rubber obtained by reacting and curing a polycaprolactone ester and a polyisocyanate described in JP-A-59-30574 is preferable.

In the present invention, the method of fixing the elastic rubber blade to the support member is preferably such that the elastic rubber blade is substantially held by the support member on the photosensitive member contact surface side. By employing such a holding method, torque fluctuation of the cleaning blade can be stabilized.

The appropriate pressure contact condition of the cleaning blade used in the image forming apparatus of the present invention will be described.

The conditions for properly pressing the elastic rubber blade against the surface of the photoreceptor are determined by a delicate balance of various characteristics, and are considerably narrow. It depends on the characteristics such as the thickness of the elastic rubber blade and the setting requires accuracy. However, the elastic rubber blades cannot be always set under appropriate conditions because the thickness of the elastic rubber blades may vary at the time of manufacture. May deviate from the appropriate area. Particularly when combined with an organic photosensitive layer using a high molecular weight binder resin, image defects such as filming and black spots are liable to occur when the organic photosensitive layer deviates from an appropriate region.

Therefore, it is necessary to take measures to cancel the variation in the characteristics of the elastic rubber blade, and even if the thickness of the elastic rubber blade varies, the pressing force against the photosensitive member surface is not affected. The above setting method will be effective.

In the present invention, the free end of the elastic rubber blade is in the direction opposite to the rotation direction of the photoconductor (counter direction).
It is preferable to press in contact.

If necessary, the cleaning blade may be spray-coated with a fluorine-based lubricant on the edge of the cleaning blade, or may be further coated with a fluorine-based polymer and a fluorine-containing polymer, as described below, on the tip portion extending over the entire width direction. It is preferable to apply a dispersion in which the base resin powder is dispersed in a fluorine-based solvent.

Next, the organic photoreceptor used in the image forming apparatus of the present invention will be described. In the present invention, an organic electrophotographic photoreceptor (organic photoreceptor) is an electrophotography constituted by providing an organic compound with at least one of a charge generation function and a charge transport function essential for the configuration of the electrophotographic photoreceptor. Photoreceptor means all known organic electrophotographic photoreceptors such as a photoreceptor composed of a known organic charge generating substance or organic charge transporting substance, and a photoreceptor having a charge generating function and a charge transporting function composed of a polymer complex. contains.

The constitution of the organic photoreceptor used in the present invention will be described below. Conductive Support As the conductive support used in the photoreceptor of the present invention, any of a sheet shape and a cylindrical shape may be used, but in order to design the image forming apparatus compactly, the conductive support of the cylindrical shape is used. Is more preferred.

The cylindrical conductive support of the present invention means a cylindrical support necessary for forming an image endlessly by rotating, and has a straightness of 0.1 mm or less and a runout of 0.1 mm or less. Conductive supports in the range are preferred. Exceeding the ranges of the roundness and the shake make it difficult to form a good image.

As the conductive material, a metal drum of aluminum, nickel, or the like, a plastic drum on which aluminum, tin oxide, indium oxide, or the like is deposited, or a paper or plastic drum coated with a conductive substance can be used. The conductive support preferably has a specific resistance of 10 ³ Ωcm or less at room temperature.

The conductive support used in the present invention may have a surface on which a sealed alumite film is formed. The alumite treatment is usually performed in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, and sulfamic acid, but anodizing treatment in sulfuric acid gives the most preferable result. In the case of anodic oxidation treatment in sulfuric acid, it is preferable that the sulfuric acid concentration is 100 to 200 g / l, the aluminum ion concentration is 1 to 10 g / l, the liquid temperature is around 20 ° C., and the applied voltage is about 20 V. It is not limited. The average thickness of the anodic oxide coating is usually 2
0 μm or less, particularly preferably 10 μm or less.

Intermediate Layer In the present invention, an intermediate layer having a barrier function may be provided between the conductive support and the photosensitive layer.

In the present invention, in order to improve the adhesiveness between the conductive support and the photosensitive layer or to prevent charge injection from the support, an intermediate layer (below the support) is provided between the support and the photosensitive layer. (Including a subbing layer). Examples of the material for the intermediate layer include polyamide resins, vinyl chloride resins, vinyl acetate resins, and copolymer resins containing two or more of the repeating units of these resins. Among these undercoating resins, a polyamide resin is preferable as a resin capable of reducing an increase in residual potential due to repeated use. The thickness of the intermediate layer using these resins is 0.01 to 0.5 μm.
Is preferred.

The intermediate layer most preferably used in the present invention is an intermediate layer using a curable metal resin obtained by thermosetting an organic metal compound such as a silane coupling agent and a titanium coupling agent. The thickness of the intermediate layer using a curable metal resin is preferably 0.1 to 2 μm.

Photosensitive Layer The photosensitive layer of the photoreceptor of the present invention may have a single-layer structure in which a charge generation function and a charge transport function are provided in one layer on the intermediate layer. It is preferable to adopt a configuration in which the functions of the layers are separated into a charge generation layer (CGL) and a charge transport layer (CTL). By adopting a configuration in which functions are separated, an increase in residual potential due to repeated use can be controlled to be small, and other electrophotographic characteristics can be easily controlled according to the purpose. In the photoreceptor for negative charging, a charge generation layer (C
GL) and a charge transport layer (CTL) thereon. In the case of a positively charged photoreceptor, the order of the layer configuration is opposite to that of the negatively charged photoreceptor. The most preferred photosensitive layer structure of the present invention is a negatively charged photosensitive member having the function-separated structure.

The constitution of the photosensitive layer of the function-separated negatively charged photosensitive member will be described below. Charge generation layer Charge generation layer: The charge generation layer contains a charge generation material (CGM). As other substances, a binder resin and other additives may be contained as necessary.

As the charge generating material (CGM), a known charge generating material (CGM) can be used. For example, phthalocyanine pigments, azo pigments, perylene pigments, azurenium pigments, and the like can be used. Among them, CGM that can minimize the increase in residual potential due to repeated use
Has a steric and potential structure capable of forming a stable aggregation structure among a plurality of molecules, and specifically includes CGM of a phthalocyanine pigment and a perylene pigment having a specific crystal structure. For example, Bragg angle 2θ for Cu-Kα ray
CGM such as titanyl phthalocyanine having a maximum peak at 27.2 ° and benzimidazole perylene having a maximum peak at 2θ of 12.4 have almost no deterioration due to repeated use, and the residual potential increase can be reduced.

When a binder is used as a dispersion medium for CGM in the charge generation layer, a known resin can be used as the binder, but the most preferred resin is a formal resin, a butyral resin, a silicone resin, a silicone-modified butyral resin, a phenoxy resin. Resins. The ratio between the binder resin and the charge generating substance is preferably from 20 to 600 parts by mass per 100 parts by mass of the binder resin. By using these resins, the increase in residual potential due to repeated use can be minimized. The thickness of the charge generation layer is preferably from 0.01 μm to 2 μm.

Charge transport layer Charge transport layer: The charge transport layer contains a charge transport material (CTM) and a binder resin for dispersing the CTM to form a film.
As other substances, additives such as antioxidants may be contained as necessary.

As the charge transport material (CTM), a known charge transport material (CTM) can be used. For example, triphenylamine derivatives, hydrazone compounds, styryl compounds, benzidine compounds, butadiene compounds and the like can be used. These charge transport materials are usually dissolved in a suitable binder resin to form a layer. Among these, the CTM that can minimize the increase in residual potential due to repeated use has a high mobility and a characteristic in which the ionization potential difference with the CGM to be combined is 0.5 (eV) or less, and is preferably 0. .25 (eV) or less.

The ionization potential of CGM and CTM is measured with a surface analyzer AC-1 (manufactured by Riken Keiki Co., Ltd.).

Examples of the resin used for the charge transport layer (CTL) include polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, and alkyd. Resins, polycarbonate resins, silicone resins, melamine resins, and copolymer resins containing two or more of the repeating units of these resins. In addition to these insulating resins, poly-
A high-molecular organic semiconductor such as N-vinylcarbazole may be used.

The most preferred binder for these CTLs is a polycarbonate resin. The polycarbonate according to the present invention has a viscosity average molecular weight of 40,0.
00 or more, more preferably 50,000
0 or more. Further, specific examples of the polycarbonate according to the present invention include JP-A-8-272125, p.
Compound P ₁ -1~P ₁ -12 according to page 14, P ₂ -1 to
P ₂ -10 and P ₃ -1~P ₃ -10, and the like. Polycarbonate resins are most preferred for improving the dispersibility and electrophotographic properties of CTM. The ratio of the binder resin to the charge transporting material is preferably from 10 to 200 parts by mass per 100 parts by mass of the binder resin. The thickness of the charge transport layer is preferably from 10 to 40 μm.

Protective Layer Various resin layers can be provided as a protective layer of the photoreceptor. In particular, by providing a crosslinked resin layer, the organic photoreceptor of the present invention having high mechanical strength can be obtained.

The solvent or dispersion medium used for forming the intermediate layer, photosensitive layer, protective layer, etc. of the present invention includes n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N- Dimethylformamide, acetone, methyl ethyl ketone, methyl isopropyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1,
2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethane, tetrahydrofuran, dioxolan, dioxane, methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl Cellosolve and the like. Although the present invention is not limited to these, dichloromethane, 1,2-dichloroethane, methyl ethyl ketone and the like are preferably used. In addition, these solvents can be used alone or as a mixed solvent of two or more kinds.

Next, as a coating method for producing the organic electrophotographic photoreceptor of the present invention, coating methods such as dip coating, spray coating and circular amount control type coating are used.
The coating process on the upper layer side of the photosensitive layer is performed by spray coating or by a circular amount control type (a typical example is a circular slide hopper type) in order to minimize dissolution of the lower layer film and achieve uniform coating. It is preferable to use It is most preferable that the protective layer of the present invention uses the above-mentioned circular amount control type coating method. The circular amount control type coating is described in detail in, for example, JP-A-58-189061.

[0253]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Example 1 << Production of Fatty Acid Lithium >> (Production of Fatty Acid Lithium 1) As a reaction apparatus, a reactor shown in FIG. 2 was used, the volume of the reaction vessel 100 was 20 L, and the length of the upper stirring blade 600 was A 275 mm long stirring blade 700 having a length of 310 mm was prepared.

In the reaction vessel of the reactor, A. V (20
4) 70% stearic acid-containing flakes (melting point 63)
℃) 2750 g, a raw material consisting of 377.6 g of lithium carbonate powder having an average particle size of 17 μm (manufactured by Nippon Chemical Industry Co., Ltd., trade name of lithium carbonate S) and 1300 ml of water (47% of the amount of the flakes). Then, the container was sealed. The temperature of the raw material at this point was 30 ° C. The rotating shaft 400 is rotated, and the raw material is rotated at a speed of 16 m / sec (rotational speed of the longer stirring blade) by the two stirring blades 600 and 700 attached to the rotating shaft.
Pass 60 ° C warm water through the jacket while stirring and mixing with
The mixture was heated. When the temperature in the reaction vessel 100 is about 4
When the temperature reaches 0 ° C., carbon dioxide gas starts to be generated and the reaction is started, the pressure in the vessel increases, and the pressure gauge installed in the reaction vessel 100 is set to 0.0196 MPa (0.2 kg / c).
m ² ). In addition, water was generated by the reaction. Subsequently, when the heating and stirring are continued so that carbon dioxide gas does not escape outside the reaction vessel 100, the reaction vessel 10
As the temperature in 0 rose, the pressure rose. In such a high-pressure atmosphere, the water in the reaction vessel 100 was present in a mist state. The maximum pressure during the reaction is 0.049 MPa
(0.5 kg / cm ² ) (at this time, the reaction vessel 100
Temperature was 60 ° C.).

When the temperature in the reaction vessel 100 reached 75 ° C., no carbon dioxide gas was generated, and the pressure was lowered and the contents were solidified at the same time, and the reaction was completed. It took 30 minutes from the input of the raw materials to the end of the reaction. Further, the water content of the reaction product was measured and found to be 15.0%.

Thereafter, the cavity 20 of the reaction vessel 100 is
0 hot water and switch to steam,
Temperature was set to 100 ° C. or higher. By performing drying under reduced pressure for 30 minutes while continuing stirring by the two stirring blades described above, a fine powder of lithium fatty acid 1 having a 200 mesh pass of 99% or more (particle size of 74 μm or less) was produced.

With respect to the obtained lithium fatty acid 1, JI
When the amount of free fatty acids was measured by the method specified in the S standard, it was 0.43% and the melting point was 217 ° C. In addition, powder X-ray diffraction was performed, and the results are shown in FIG.

(Production of Lithium Fatty Acids 2 to 5) In the production of lithium fatty acid 1 described above, the reaction time and the drying time under reduced pressure were changed to obtain a fatty acid component, a water content (% by mass), a free fatty acid as shown in Table 1. Lithium fatty acids 2 to 5 were produced in the same manner except that the amounts (% by mass) were adjusted.

(Production of Lithium Fatty Acid 6) In the production of lithium fatty acid 1, as shown in Table 1, stearic acid and palmitic acid were used instead of stearic acid at a mass ratio of 3
In the same manner except that 99: 171, fatty acid lithium 6
I got

Table 1 shows the properties of the obtained lithium salt of fatty acid.

[0262]

[Table 1]

<< The inorganic / organic composite fine particles used in the present invention
Production >> Styrene / acrylic organic with average particle size of 1.0μm
Fine particles (electrical resistance 6.6 × 10¹³Ω · cm) 100g
On the other hand, the surface having a primary particle diameter of 30 nm was treated with tin oxide.
Titanium oxide particles trade name ET-300W (Ishihara Sangyo Co., Ltd.)
Was added and mixed with a turbula mixer. One
A hybridizer with a modified crusher (Nara Machinery Co., Ltd.)
For 3 minutes at a peripheral speed of 100 m / sec.
Inorganic oxide with titanium oxide fixed on the surface of organic fine particles
Machine composite fine particles were prepared. This is called "inorganic / organic composite fine particles.
Child 1 ". The electric resistance of the inorganic / organic composite fine particles 1 is
4.8 × 10 ⁸Ω · cm.

<< Production Example of Resin Particles for Toner >> (Latex: Preparation of 1HML) (1) Preparation of core particles (first stage polymerization): 5000 m equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device
, a surfactant solution (aqueous medium) prepared by dissolving 7.08 g of an anionic surfactant (sodium dodecylsulfonate: SDS) in 3010 g of ion-exchanged water is charged into a 1 l separable flask, and stirred at 230 rpm in a nitrogen stream. While stirring at, the internal temperature was raised to 80 ° C.

To this surfactant solution was added 9.2 g of a polymerization initiator (potassium persulfate: KPS) in 200 g of ion-exchanged water.
Was added, and the temperature was adjusted to 75 ° C., and then 70.1 g of styrene and n-butyl acrylate 1 were added.
A monomer mixture composed of 9.9 g and 10.9 g of methacrylic acid was added dropwise over 1 hour, and the system was heated and stirred at 75 ° C. for 2 hours to perform polymerization (first-stage polymerization). Latex (a dispersion of resin particles composed of a high molecular weight resin) was prepared. This is designated as “latex (1H)”.

(2) Formation of an intermediate layer (second stage polymerization): In a flask equipped with a stirrer, styrene 10
A compound represented by the above 19) was added to a monomer mixture comprising 5.6 g, 30.0 g of n-butyl acrylate, 6.4 g of methacrylic acid, and 5.6 g of n-octyl-3-mercaptopropionate (hereinafter referred to as 19). , "Exemplified compound (1
9) ". ) 72.0 g was added, and the mixture was heated to 80 ° C and dissolved to prepare a monomer solution.

On the other hand, an anionic surfactant (SDS)
A surfactant solution obtained by dissolving 1.6 g in 2700 ml of ion-exchanged water was heated to 80 ° C.
After adding 28 g of the latex (1H), which is a dispersion of core particles, in terms of solid content, the dispersion was exemplarily measured using a mechanical disperser “CLEARMIX” (manufactured by M Technic Co., Ltd.) having a circulation path. A monomer solution of the compound (19) is mixed and dispersed, and a uniform dispersed particle size (284
A dispersion liquid (emulsion liquid) containing emulsified particles (oil droplets) having the following formula:

Next, to this dispersion liquid (emulsion liquid) were added an initiator solution obtained by dissolving 5.1 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water, and 750 ml of ion-exchanged water. Polymerization (second-stage polymerization) is carried out by heating and stirring at 3 ° C. for 3 hours, and latex (a dispersion of composite resin particles having a structure in which the surface of resin particles composed of a high molecular weight resin is coated with an intermediate molecular weight resin) is used. Obtained.
This is referred to as “latex (1HM)”.

(3) Formation of outer layer (third stage polymerization): An initiator obtained by dissolving 7.4 g of a polymerization initiator (KPS) in 200 ml of ion-exchanged water in the latex (1HM) obtained as described above. The solution was added, and a monomer mixture consisting of 300 g of styrene, 95 g of n-butyl acrylate, 15.3 g of methacrylic acid, and 10.4 g of n-octyl-3-mercaptopropionate was added under a temperature condition of 80 ° C. It was dropped over time. After completion of the dropping, polymerization (third stage polymerization) is performed by heating and stirring for 2 hours.
After cooling to 28 ° C., a latex (having a central portion composed of a high molecular weight resin, an intermediate layer composed of an intermediate molecular weight resin, and an outer layer composed of a low molecular weight resin,
9) was obtained.
This latex is referred to as “latex (1HML)”.

The composite resin particles constituting this latex (1HML) were 138,000, 80,000 and 1
It has a peak molecular weight of 3,000,
The number average particle diameter of the composite resin particles was 102 nm.

(Preparation of latex 2HL) (1) Preparation of core particles (first-stage polymerization): In a flask equipped with a stirrer, 105.6 g of styrene, n-
30.0 g of butyl acrylate, 6.4 g of methacrylic acid
Compound (16) in a monomer mixture consisting of 72.0
g was added, and the mixture was heated to 80 ° C. and dissolved to prepare a monomer solution.

On the other hand, an anionic surfactant (SDS)
A surfactant solution obtained by dissolving 1.6 g in 2700 ml of ion-exchanged water was heated to 80 ° C.
Mechanical dispersion machine with a circulation path "CLEARMIX (CL
EARMIX) ”(manufactured by M Technique Co., Ltd.), by mixing and dispersing the monomer solution of Exemplified Compound (16) to obtain a dispersion liquid containing emulsified particles (oil droplets) having a uniform dispersed particle diameter (268 nm). (Emulsion liquid) was prepared.

Next, to this dispersion liquid (emulsion liquid) were added an initiator solution obtained by dissolving 5.1 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water, and 750 ml of ion-exchanged water. Polymerization (first-stage polymerization) was carried out by heating and stirring at 3 ° C. for 3 hours to prepare a latex (a dispersion of resin particles composed of a high molecular weight resin). This is designated as “latex (2H)”.

(2) Formation of outer layer (second stage polymerization): An initiator obtained by dissolving 14.8 g of a polymerization initiator (KPS) in 400 ml of ion-exchanged water in the latex (2H) obtained as described above. The solution was added, and a monomer mixture comprising 600 g of styrene, 190 g of n-butyl acrylate, 30.0 g of methacrylic acid, and 20.8 g of n-octyl-3-mercaptopropionate was added at 80 ° C. under a temperature condition of 1 g. It was dropped over time. After completion of the dropwise addition, polymerization (second-stage polymerization) is carried out by heating and stirring for 2 hours, and then cooled to 28 ° C. to form a latex (having a central portion composed of a high molecular weight resin and an outer layer composed of a low molecular weight resin). Thus, a dispersion of composite resin particles containing the exemplary compound (16) in the center was obtained. This latex is referred to as “latex (2HL)”.

The composite resin particles constituting the latex (2HL) had peak molecular weights of 168,000 and 11,000, and the weight average particle size of the composite resin particles was 126 nm.

<< Production Example of Colored Particle >> (Production of Colored Particle 1) Sodium n-dodecyl sulfate 5
9.0 g was dissolved under stirring in 1600 ml of ion-exchanged water.
While stirring this solution, 420.0 g of carbon black "REGAL 330" (manufactured by Cabot) is gradually added, and then dispersed using "CLEARMIX" (manufactured by M Technique Co., Ltd.). And a dispersion of colorant particles (hereinafter referred to as “colorant dispersion”). When the particle size of the colorant particles in this colorant dispersion was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle size was 9%.
It was 8 nm.

A latex (1HML) of 420.7 g (in terms of solid content), 900 g of ion-exchanged water, and 166 g of a colorant dispersion were charged with a temperature sensor, a cooling pipe, a nitrogen introducing device,
A reaction vessel equipped with a stirrer, a particle size and shape monitoring device (reactor having the configuration shown in FIG. 4, intersection angle α)
Was 25 °) (reactor having the structure shown in FIG. 4; crossing angle α was 25 °) and stirred. After adjusting the internal temperature to 30 ° C,
To this solution was added a 5 mol / L aqueous solution of sodium hydroxide to adjust the pH to 11.0.

Subsequently, magnesium chloride hexahydrate12.
An aqueous solution obtained by dissolving 1 g in 1000 ml of ion-exchanged water,
The solution was added at 30 ° C. over 10 minutes with stirring. After standing for 3 minutes, heating was started, and the temperature of the system was raised to 90 ± 3 ° C. over 6 to 10 minutes (heating rate = 10 ° C./min). In this state, the particle size of the associated particles was measured with a “Coulter counter TA-II”, and when the volume average particle size reached 5.5 μm, 80.4 g of sodium chloride was added to ion-exchanged water 1
An aqueous solution dissolved in 000 ml was added to stop the particle growth, and further, as a maturing treatment, the mixture was heated and stirred at a liquid temperature of 85 ± 2 ° C. for 0.5 to 15 hours to continue the fusion.

Thereafter, the mixture was cooled to 30 ° C. under the condition of 8 ° C./min, the pH was adjusted to 2.0 by adding hydrochloric acid, and the stirring was stopped. The generated associated particles are filtered using a Nutsche, washed repeatedly with ion-exchanged water, and then dried at a suction air temperature of 60 ° C. using a flash jet dryer,
Then dried at a temperature of 60 ° C. using a fluid bed dryer,
Colored particles 1 containing the release agent [exemplary compound (19)] and having the physical properties shown in Table 2 were obtained.

(Production of Colored Particles 2 to 4) In the production of the colored particles 1 described above, in the monitoring of the salting-out / fusion step and the shape control step, the number of rotations and the heating time are controlled to control the shape. Colored particles 2 to 4 having the shape characteristics and the particle size distribution characteristics shown in Table 2 were obtained in the same manner, except that the coefficient of variation of the shape factor and the coefficient of variation of the shape factor were controlled and the coefficient of variation of the particle size and the particle size distribution were arbitrarily adjusted. .

(Production of Colored Particles 5 to 8) Latex (1
HML) instead of latex (2HL) 420.7 g
Using (solid content conversion), colored particles 5 to 8 each having the shape characteristics and particle size distribution characteristics shown in Table 2, in the same manner as colored particle production examples 1 to 4 except that the aging treatment time was changed, Obtained. Table 2 shows the physical properties of the obtained colored particles.

[0282]

[Table 2]

<< Production of Toner Particles >> Hydrophobic silica (number average primary particle diameter = 10 nm, degree of hydrophobicity = 63) was added to each of the coloring particles 1 to 8 thus obtained at 1.0% by mass. , And hydrophobic titanium oxide (number average primary particle size = 25 nm, degree of hydrophobicity = 60) was added at a ratio of 0.8% by mass, respectively, and mixed with a Henschel mixer. Further, 0.1% by mass of a lithium salt of a fatty acid and 1% by mass of inorganic / organic composite fine particles or strontium titanate shown in Table 3 were added and mixed by a Henschel mixer, and the toner for developing an electrostatic image shown in Table 3 was added. Samples 1 to 15 were each manufactured.

In preparing toner sample 1, a toner to which no fatty acid lithium salt was added was prepared as comparative toner 1. In the preparation of the toner sample 1, a comparative toner 2 was prepared by adding zinc stearate (Zinc Stearate D manufactured by NOF Corporation) without using a lithium fatty acid salt.

[0285]

[Table 3]

Here, the relationship between the physical properties of the toner particles for developing an electrostatic image and the colored particles according to the present invention will be described.

In the production of the colored particles according to the present invention,
The resin particles and the colorant are monitored during the salting-out / fusion step and the shape control step, and by controlling the reaction such as the number of rotations for stirring and the heating time, the variation coefficient of the shape and the shape coefficient are controlled. Adjust the coefficient of variation of the distribution. An external additive is added to the thus obtained colored particles to produce toner particles.However, the external additive is merely fixed to the surface of the toner particles and does not physically change the colored particles. The physical characteristics (shape, particle size, etc.) of the toner particles are the same as the physical characteristics of the colored particles.

<< Manufacture of Carrier >> (Manufacture of Ferrite Core Material) MnO of 22 mol%, Fe
78 mol% of ₂ O ₃ was pulverized by a wet ball mill for 2 hours,
After mixing and drying, the mixture was calcined by holding at 900 ° C. for 2 hours, and the mixture was pulverized with a ball mill for 3 hours to form a slurry. A dispersant and a binder were added, and the mixture was granulated and dried by a spray drier.
The main firing was performed for a time to obtain ferrite core material particles having an average grain diameter of 5.2 μm and a resistance of 4.3 × 10 ⁸ Ω.

(Production of Resin-Coated Carrier) First, the concentration in an aqueous medium using sodium benzenesulfonate having an alkyl group having 12 carbon atoms as a surfactant was adjusted to 0.
Cyclohexyl methacrylate / methyl methacrylate (copolymerization ratio: 5/5) by emulsion polymerization at 3% by mass.
Was synthesized, and a volume average primary particle size of 0.1 μm, a weight average molecular weight (Mw) of 200,000, a number average molecular weight (Mn) of 91,000, Mw / Mn = 2.2, and a softening point temperature (Tsp) ) 230 ° C and glass transition temperature (Tg) 11
0 ° C. resin fine particles were obtained. In the emulsified state, the resin fine particles azeotrope with water and have a residual monomer amount of 510P.
PM.

Next, 100 parts by mass of the ferrite core material particles and 2 parts by mass of the resin fine particles were put into a high-speed stirring mixer equipped with stirring blades, and stirred and mixed at 120 ° C. for 30 minutes.
A resin-coated carrier having a volume average particle diameter of 61 μm was obtained by using the action of a mechanical impact force.

<< Manufacture of Developer >> Toner samples 1 to 15 and comparative toner samples 1 and 2 shown in Table 3 were mixed with the above carriers to prepare a developer having a toner concentration of 6% by mass. . The obtained developers were each used as a developer sample 1 to 15,
Developers 1 and 2 for comparison.

<< Production of Photoconductor >> 30 g of polyamide resin Amilan CM-8000 (manufactured by Toray Industries, Inc.) was treated with 900 parts of methanol.
The mixture was poured into a mixed solvent of 100 ml of 1 ml of 1-butanol and dissolved by heating at 50 ° C. This solution was prepared with an outer diameter of 60 mm and a length of 3
The composition was applied on a 60 mm cylindrical aluminum conductive support to form a 0.5 μm thick intermediate layer.

Next, 10 g of a silicone resin KR-5240 (manufactured by Shin-Etsu Chemical Co., Ltd.) was dissolved in 1000 ml of t-butyl acetate, and Y-TiOPc (JP-A 64-17066) was added thereto.
No., Fig. 1) 10 g was mixed and 20
After time dispersion, a coating solution for the charge generation layer was obtained. This liquid was used to coat the intermediate layer to form a 0.3 μm thick charge generation layer.

Next, 150 g of CTM (T-1: N- (4-methylphenyl) -N- {4- (β-phenylstyryl) phenyl} -p-toluidine) and a viscosity average molecular weight of 2
200 g of 10,000 polycarbonate resin Iupilon Z-200 (manufactured by Mitsubishi Gas Chemical Co., Ltd.) was added to 1,2-dichloroethane 10
The solution was dissolved in 00 ml to obtain a charge transport layer coating solution. This liquid was used to coat the charge generation layer on a circular slide hopper, and then dried at 100 ° C. for 1 hour to form a charge transport layer having a thickness of 22 μm. Thus, a photoreceptor (P1) including the intermediate layer, the charge generation layer, and the charge transport layer was obtained. Then, CTM (T-1) was added on the surface of the photoconductor sample (P1).
30 g and 50 g of polycarbonate resin Iupilon Z-800 (manufactured by Mitsubishi Gas Chemical Company) having a viscosity average molecular weight of 80,000 are mixed with 1,000 ml of 1,2-dichloroethane.
Using a coating solution dissolved in, a coating was performed on the charge transport layer with a circular slide hopper, and then dried at 100 ° C. for 1 hour to form a 5 μm thick overcoat layer, and the photoconductor (P2) I got

The obtained photoreceptor (P2) was placed in a high-temperature, high-humidity environment (temperature: 33 ° C., relative humidity: 8) using a remodeling machine mounted on a commercially available digital copying machine Konica Sitios 7030.
0%), an image with a pixel rate of 15% is continuously 30
A real-photograph test was conducted to form all the sheets to evaluate the amount of blade abrasion, slippage of toner particles, image blur, and environmental dependence of image density.

<Blade Abrasion> After printing 100,000 sheets, the cleaning blade was removed from the cleaning device, and the length of the portion disappeared due to wear was measured with a laser microscope. If the amount of wear is within 20 μm, there is no problem (practicable).

<< Slipping of Toner Particles >> The number of sheets which were detected (visually evaluated) as image stains by passing toner on the photoreceptor from the cleaning device in the white area of the image was evaluated.

<< Image Blur >> A character image having a character size of 5 points was formed on the entire image, and the number of sheets until the image was locally blurred or a portion where toner bleeding around the image was detected was visually evaluated. More than 200,000 sheets can be used.

<< Environmental Dependence of Image Density >> The maximum image density of the solid image portion was measured with a Macbeth reflection densitometer. High temperature and high humidity environment (33 ° C, 80% RH) and low temperature and low humidity environment (1
At 0 ° C., 20% RH), a difference of less than 0.05 was evaluated as “◎”, a value between 0.05 and 0.1 as “○”, and a value exceeding 0.1 as “×”.

Table 4 shows the obtained results.

[0301]

[Table 4]

From Table 4, it can be seen that the sample of the present invention was
It is clear that the abrasion of the cleaning blade and the penetration of the toner particles are small, and that the image blur and the environmental dependency of the image density are also good.

[0303]

According to the present invention, the toner particles do not slip through the cleaning device during image formation, the amount of wear of the cleaning blade of the cleaning device is reduced, the image is not blurred, and the image of the formed image is formed. It is possible to provide a toner for developing an electrostatic charge image, a method of manufacturing the same, and an image forming apparatus, which have a small environmental dependency of the density.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a fixing device (fixing device) used in the present invention.

FIG. 2 is a cross-sectional view showing an example of an apparatus used for producing a fatty acid lithium salt according to the present invention.

FIG. 3 is a characteristic diagram showing a powder X-ray diffraction pattern of a fine powder of lithium stearate produced in Example 1 of the present invention.

FIG. 4 is a perspective view of an example of a stirring tank provided with stirring blades.

FIG. 5 is a schematic diagram illustrating toner particles without corners.

[Description of Signs] 1 jacket 2 stirring tank 3 rotation axis 4, 5 stirring blade 9 baffle plate α crossing angle between stirring blades 8 image holder 10 heating roll 11 core metal of heating roll 12 coating layer of heating roll 13 heating member Reference Signs List 20 pressure roll 21 core metal of pressure roll 22 coating layer of pressure roll T toner image 100 container 200 cavity 300 hole 400 rotation shaft 500 bearing 600, 700 stirring blade 800 lid

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) G03G 9/08 381 384 (72) Inventor Yoshiaki Kobayashi 2970 Ishikawacho, Hachioji City, Tokyo Konica Corporation (72 Inventor Tomomi Oshiba 2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H005 AA01 AA08 AA15 AB03 AB06 CA30 EA05 EA06 EA07 2H068 AA13 BB25 BB52

Claims (18)

[Claims] 1. An electrostatic image developing toner having toner particles obtained by polymerizing a polymerizable monomer in an aqueous medium, wherein the toner has a fatty acid lithium salt as at least one external additive. A toner for developing electrostatic images, characterized in that: 2. The method according to claim 1, wherein the fatty acid lithium salt has a water content of 0.1% by mass to 1.4% by mass, and the free fatty acid amount in the toner is 0.01% by mass to 0.7% by mass. The toner for developing electrostatic images according to claim 1. 3. The electrostatic image developing toner according to claim 1, wherein the fatty acid lithium salt is lithium stearate. 4. The electrostatic image developing device according to claim 1, wherein the toner particles are produced through a process of aggregating and fusing the resin particles in an aqueous medium. toner. 5. The method according to claim 1, wherein the toner particles are used as an external additive on the surface of the organic fine particles having an average particle size of 0.1 μm to 5.0 μm.
The toner for developing an electrostatic charge image according to any one of claims 1 to 4, further comprising inorganic / organic composite fine particles having inorganic fine particles having a primary average particle diameter of 5 nm to 100 nm fixed thereto. 6. The toner particles have a number average particle size of 2 μm to 8 μm.
The electrostatic image development according to any one of claims 1 to 5, wherein the coefficient of variation of the shape factor is 16% or less, and the number variation coefficient in the number particle size distribution is 27% or less. For toner. 7. The toner particles have a number average particle diameter of 2 μm to 8 μm.
The toner according to any one of claims 1 to 5, wherein the ratio of the toner particles having a shape factor of 1.0 to 1.6 is 65% by number or more of all the toner particles. The toner for developing an electrostatic image according to the above. 8. The number average particle diameter of the toner particles is 2 μm to 8 μm.
The toner according to any one of claims 1 to 5, wherein the ratio of the toner particles having a shape coefficient of 1.2 to 1.6 in all the toner particles is 65% by number or more. The toner for developing an electrostatic image according to the above. 9. The toner according to claim 1, wherein the number average particle diameter of the toner particles is 2 μm to 8 μm.
The toner for developing an electrostatic image according to any one of claims 1 to 8, wherein the ratio of the toner particles having no corners to all toner particles is 50% by number or more. 10. When the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.23.
The relative frequency (m1) of the toner particles included in the most frequent class in the histogram indicating the number-based particle size distribution divided into a plurality of classes at intervals, and the toner included in the next most frequent class after the most frequent class The sum (M) of the relative frequency (m2) of the particles is at least 70%.
10. The electrostatic image developing toner according to any one of items 9 to 9. 11. The method according to claim 1, wherein the ratio of the toner particles having no corners to all the toner particles is 50% by number or more, and the number variation coefficient in the number particle size distribution is 27% or less. Item 2. The toner for developing an electrostatic image according to Item 1. 12. The ratio of toner particles having a shape factor in the range of 1.2 to 1.6 to all toner particles is 65% by number.
The electrostatic image developing toner according to any one of claims 1 to 11, wherein the variation coefficient of the shape factor is 16% or less. 13. The method according to claim 1, wherein the toner particles are produced through a step of salting out, aggregating, and fusing the composite resin particles obtained by the multi-stage polymerization method and the colorant particles.
13. The toner for developing an electrostatic image according to any one of items 12 to 12. 14. In a GPC (gel permeation chromatography) measurement of a toner, a peak or a shoulder has at least 100,000 to 1,000,000.
The electrostatic image developing toner according to any one of claims 1 to 13, wherein the toner is present at 0 and between 1,000 and 50,000. 15. In a GPC (gel permeation chromatography) measurement of the toner, a peak or a shoulder has at least 100,000 to 1,000,000.
0, 25,000-100,000, 1,000-
2. The method according to claim 1, wherein the number of the components is 25,000.
4. The toner for developing an electrostatic charge image according to any one of 3. 16. An electrostatic image formed on an organic photoreceptor is developed with a developer having the electrostatic image developing toner according to any one of claims 1 to 15, and the developed image is developed. An image forming apparatus comprising: a cleaning device that removes the toner remaining on the organic photoconductor after transferring the converted toner image from the organic photoconductor to a transfer material. 17. The method according to claim 1, wherein the organic photoreceptor has a photosensitive layer on a conductive support, and the surface layer of the photosensitive layer contains polycarbonate having an average molecular weight of 40,000 or more.
7. The image forming apparatus according to 6. 18. In producing the toner for developing an electrostatic image according to any one of claims 1 to 15, particles are formed in an aqueous medium, and after the particles are dried, a fatty acid lithium salt is added to 0.1%. A method for producing a toner for developing an electrostatic image, comprising adding externally in the range of 005% by mass to 0.3% by mass to produce toner particles.