JP2001222130A - Image forming device and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excellent electrophotographic image by using an image forming device using an intermediate transfer body and to provide the image forming device and an image forming method by which an image defect such as registration deviation is not caused on a superposed color image on the intermediate transfer body even in the case of forming images for many sheets and the image blurring and the black spot are not caused on the obtained image. SOLUTION: In this image forming device using the intermediate transfer body, the variation coefficient of the shape factor of toner used in the developing means of the image forming device is <=16%, the number variation coefficient thereof is <=27%, and film thickness wear amount ΔHd (μm) per one rotation of an electrophotographic sensitive body in a wearing test is 0<=ΔHd<1×10-5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus used as a copying machine or a printer, and an image forming method. In particular, the present invention relates to an image forming apparatus used as a color copying machine or a color printer, and an image forming method.

[0002]

2. Description of the Related Art In recent years, color copiers and color printers have a strong tendency to obtain color images. Color image forming methods of high practical value can be roughly classified into commonly used names, such as a transfer drum method, an intermediate transfer method, a KNC method (a method of forming a multi-color superimposed image on a photoconductor and collectively transferring), a tandem method. There are four types of methods.

Needless to say, these are names given from different viewpoints, and there are, of course, intermediate transfer systems and tandem systems. However, among them, an intermediate transfer type color image forming apparatus is known to be capable of obtaining a high quality full color image. In this method, one color is used for each of yellow, magenta, cyan, and black.
In this method, a single photoconductor is used, or each photoconductor corresponding to each color is used, a color superimposed image is formed on an intermediate transfer body, and the images are collectively transferred to a transfer material.

On the other hand, as an electrophotographic photosensitive member (hereinafter simply referred to as a photosensitive member), an organic photosensitive member using an organic photoconductive substance has been widely used. The organic photoreceptor is advantageous in that materials corresponding to various exposure light sources from visible light to infrared light can be easily developed, materials that do not cause environmental pollution can be selected, and manufacturing costs are low. However, the only drawback is that the mechanical strength is weak, and the surface of the photoreceptor is deteriorated by wear and scratches are generated during copying and printing of a large number of sheets.

When such a photosensitive member is employed in the image forming apparatus of the above-mentioned intermediate transfer system, the coefficient of friction between the surface of the intermediate transfer member and the surface of the photosensitive member changes under high temperature and high humidity, and color superposition on the intermediate transfer member is performed. It has been found that image defects such as registration deviation (registration deviation) occur in the image. As a countermeasure for this, it has been studied to provide a photosensitive layer or a surface protective layer containing a highly durable organosilicon binder resin. This binder resin layer has an extremely low amount of wear, and has the advantage that the photoreceptor maintains substantially the same film thickness as the initial state even after long-term use, but image blurring due to filming of toner or paper powder on the photoreceptor surface, Defects such as image deletion are likely to occur.
Particularly in an image forming apparatus using an intermediate transfer member, these problems tend to be amplified and generated.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a good electrophotographic image using an image forming apparatus using an intermediate transfer member. It is an object of the present invention to provide an image forming apparatus and an image forming method which do not cause image defects such as misregistration, and which do not cause image defects such as image blur and black spots in the obtained image.

[0008]

The object of the present invention is attained by adopting one of the following constitutions.

1. The toner image formed on the electrophotographic photosensitive member is temporarily transferred onto an intermediate transfer member by a developing means installed around the electrophotographic photosensitive member, and then the toner image on the intermediate transfer member is transferred to a transfer material. In an image forming apparatus which transfers and removes residual toner on the surface of the electrophotographic photosensitive member by a cleaning unit, the coefficient of variation of the shape factor of the toner used in the developing unit is 16% or less, and the number variation coefficient is 27%.
And the film thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member in the wear test is 0 ≦
An image forming apparatus, wherein ΔHd <1 × 10 ⁻⁵ .

[0010] 2. A plurality of developing means containing at least a different hue toner is installed around the electrophotographic photoreceptor,
By sequentially operating the plurality of developing units, a toner image formed on the electrophotographic photosensitive member corresponding to each developing unit is sequentially superimposed on an intermediate transfer member to form a color toner image. In the image forming apparatus, the color toner image on the intermediate transfer member is collectively transferred to a transfer material, and the residual toner on the electrophotographic photosensitive member is removed by a cleaning unit after the transfer of the color toner on the intermediate transfer member. The variation coefficient of the shape factor of the toner used in the means is 16% or less;
And the number variation coefficient is 27% or less, and the film thickness loss amount ΔHd (μm) per rotation of the electrophotographic photosensitive member in the wear test is 0 ≦ ΔHd <1 × 10 ^−5. Image forming apparatus.

3. A plurality of sets of charging means, image exposing means and developing means are provided for the electrophotographic photosensitive member, and charging, image exposing and developing are repeated during one rotation of the electrophotographic photosensitive member, and the peripheral surface of the electrophotographic photosensitive member is In a color image forming apparatus for forming a plurality of toner images in a superimposed manner, transferring the superimposed color toner images collectively onto an intermediate transfer member, and then transferring the image to a transfer material, the shape factor of the toner used in the developing means Has a variation coefficient of 16% or less and a number variation coefficient of 27%
And the film thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member in the wear test is 0 ≦
An image forming apparatus, wherein ΔHd <1 × 10 ⁻⁵ .

4. 4. The image forming apparatus according to claim 1, wherein the electrophotographic photosensitive member is an electrophotographic photosensitive member having at least a plurality of resin layers on a cylindrical conductive support.

5. One of the plurality of resin layers is a surface layer, and the surface layer has a structural unit having charge transport performance,
5. The image forming apparatus as described in 4 above, further comprising a siloxane-based resin having a crosslinked structure.

6. A siloxane-based resin having a structural unit having the charge transport performance, and a siloxane-based resin having a cross-linked structure, a hydroxyl group, or an organosilicon compound having a hydrolyzable group,
6. The image forming apparatus as described in 5 above, which is a siloxane-based resin obtained by reacting a compound represented by the following general formula (2).

Formula (2) B- (R₁-ZH)_m In the formula, B is a monovalent or monovalent compound containing a structural unit having charge transporting performance
Represents a polyvalent group; ₁Is a single bond or divalent alkylene
Z represents an oxygen atom, a sulfur atom or NH;
Represents an integer of 1 to 4.

[7] 7. The image forming apparatus according to the item 6, wherein Z in the general formula (2) is an oxygen atom.

8. The image forming apparatus according to any one of the above items 5 to 7, wherein an antioxidant is contained in the surface layer.

9. 9. The image forming apparatus according to claim 8, wherein the antioxidant is a hindered phenol antioxidant or a hindered amine antioxidant.

10. Any one of the above items 5 to 9, wherein the surface layer contains organic or inorganic particles.
Item 10. The image forming apparatus according to item 1.

11. The image forming apparatus according to any one of Items 5 to 10, wherein the surface layer contains colloidal silica.

[12] Wherein the toner used in the developing means contains at least 65% by number of toner particles having a shape factor in the range of 1.0 to 1.6.
The image forming apparatus according to claim 1.

13. Wherein the toner used in the developing means has a volume average particle diameter of 4 to 9 μm and toner particles having a volume average particle size of 3.0 μm or less are 30% by number or less.
13. The image forming apparatus according to claim 12.

14. When the particle diameter of the toner used in the developing means is D (μm), the natural logarithm InD is plotted on the horizontal axis, and the horizontal axis shows the number-based particle size distribution divided into a plurality of classes at intervals of 0.23. In the histogram, the relative frequency sum (M ₁ ) of the relative frequency (m ₁ ) of the toner particles included in the most frequent class and the relative frequency (m ₂ ) of the toner particles included in the next frequent class after the most frequent class ) Is 70% or more, the image forming apparatus according to any one of 1 to 13 above.

[15] The toner image formed on the electrophotographic photosensitive member is temporarily transferred to an intermediate transfer member by a developing process installed around the electrophotographic photosensitive member, and then the toner image on the intermediate transfer member is transferred to a transfer material. In the image forming method for transferring and removing the residual toner on the surface of the electrophotographic photoreceptor by a cleaning step, the variation coefficient of the shape factor of the toner used in the development step is 16% or less and the number variation coefficient is 27%.
% Or less, and the thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member in the abrasion test is 0.
.Ltoreq..DELTA.Hd <1.times.10.sup.- ⁵ .

16. A plurality of developing steps containing at least toners having different hues are provided around the electrophotographic photosensitive member, and the plurality of developing steps are sequentially operated to form a plurality of developing steps on the electrophotographic photosensitive member corresponding to each developing step. The color toner image is formed by sequentially superimposing the toner images to be formed on the intermediate transfer body, the color toner image on the intermediate transfer body is collectively transferred to a transfer material, and the color toner is transferred onto the intermediate transfer body. In an image forming method for removing residual toner on the electrophotographic photoreceptor by a cleaning step later, the coefficient of variation of the shape factor of the toner used in the developing step is 16% or less, and the number variation coefficient is 27% or less; An image forming method, wherein the film thickness loss per rotation ΔHd (μm) of the electrophotographic photosensitive member in the wear test is 0 ≦ ΔHd <1 × 10 ⁻⁵ .

17. A plurality of sets of charging step, image exposure step and development step are provided for the electrophotographic photosensitive member, and charging, image exposure and development are repeated during one rotation of the electrophotographic photosensitive member,
In the color image forming method, a plurality of toner images are formed by superimposing on the peripheral surface of the electrophotographic photoreceptor, and the superimposed color toner images are collectively transferred onto an intermediate transfer body and then transferred to a transfer material. The variation coefficient of the shape factor of the toner used in the process is 16% or less, and the number variation coefficient is 27
% Or less, and the thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member in the abrasion test is 0.
.Ltoreq..DELTA.Hd <1.times.10.sup.- ⁵ .

As a result of intensive studies, the present inventors have found the following facts. In the image forming apparatus using the intermediate transfer member of the present invention, a photoreceptor having a resin layer which is not easily worn as a photoreceptor (hereinafter also referred to as an electrophotographic photoreceptor) is used, and the toner is similarly used in the image forming apparatus. By using a toner having a coefficient variation coefficient of 16% or less and a number variation coefficient of 27% or less, the superimposed color image on the intermediate transfer member is free from image defects such as misregistration, and the obtained image An image forming apparatus that does not cause image blur, image deletion, and the like can be obtained.

The present invention will be described in more detail. Next, the toner and the developer used in the present invention will be described.

<< Toner used in the present invention >><Shape coefficient of toner>"Shapecoefficient" of the toner of the present invention
Is represented by the following formula, and indicates the degree of roundness of the toner particles.

Shape factor = [(maximum diameter / 2) ² × π] / projected area Here, the maximum diameter is defined as a parallel line when a projected image of a toner particle on a plane 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 is determined by taking a photograph in which the toner particles are magnified 2,000 times by a scanning electron microscope, and referring to this photograph based on “SCANNING”.
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.

In the toner of the present invention, the ratio of the toner particles whose shape factor is in the range of 1.0 to 1.6 is set to 65.
% Or more, more preferably 7% or more.
0% by number or more. More preferably, the ratio of the toner particles whose shape factor is in the range of 1.2 to 1.6 is set to 65%.
% Or more, and more preferably 70% or more.

Effect of Toner Shape Factor on the Present Invention When a toner having the same shape factor is used for a plurality of color toners used in the image forming apparatus of the present invention, the charging characteristics among the color toners can be made uniform. In addition, it is possible to reduce color misregistration of a color image generated when a large number of the same color images are produced. Also, the surface of the photoreceptor on which the image of each color toner is formed is uniform because the shape factors of the respective color toners are uniform, so that the surface deterioration of the photoreceptor becomes uniform, which also produces many sheets of the same color image. The color shift of the color image generated at the time can be reduced, and a uniform and good color image can be produced.

Further, when a toner having a shape factor of 65% by number or more in which the ratio of toner particles in the range of 1.0 to 1.6 is used, the toner particles are hard to be crushed and the generation of fine particle toner is reduced. This prevents toner filming of the photoconductor due to defective cleaning.

The method for controlling the shape factor is not particularly limited. For example, a method of spraying toner particles in a hot air flow, a method of repeatedly applying mechanical energy by an impact force in a gaseous phase in a gas phase, a method of adding a toner in a solvent that does not dissolve a toner and imparting a swirling flow, etc. A method of preparing toner particles having a shape factor of 1.0 to 1.6 or 1.2 to 1.6, and adding the particles to a normal toner so as to fall within the range of the present invention. is there.
Further, the overall 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 to 1.2.
There is a method in which the toner particles adjusted to 1.6 are similarly added to a normal toner for adjustment.

Among the above methods, polymerization toners are preferred in that they are simple as a production method and are superior in surface uniformity as compared with pulverized toners.

<Coefficient of Variation of Shape Factor of Toner> The “coefficient of variation of shape coefficient” of the toner of the present invention is calculated from the following equation.

Coefficient of variation of toner shape coefficient = [S ₁ /
K] × 100 (%) In the formula, S ₁ represents the standard deviation of the shape factor of 100 toner particles, and K represents the average value of the shape factor.

By using a toner having a variation coefficient of the shape factor of 16% or less in the image forming apparatus of the present invention, the effect described in the effect of the shape factor is more remarkably exhibited.
A more preferable variation coefficient of the shape factor is 14% or less.

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

Monitoring means that a measuring device is incorporated in-line and process conditions are controlled based on the measurement result. That is, for example, in the case of a polymerization toner formed by incorporating measurement of shape and the like in-line and associating or fusing resin particles in an aqueous medium, the shape and particle size are sequentially sampled in steps 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.

<Number Variation Coefficient of Toner> The number particle size distribution and number variation coefficient of the toner of the present invention are measured with a Coulter Counter TA or Coulter Multisizer (manufactured by Coulter Co.). 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 particle size distribution and the average particle size were calculated by measuring the volume and the number of toner particles having a size of 2 μm or more by using a 100 μm aperture as the aperture used in the Coulter Multisizer. The number particle size distribution represents the relative frequency of the toner particles with respect to the particle size, and the number average particle size represents the median size in the number particle size distribution. "Number variation coefficient in number particle size distribution" of toner (hereinafter referred to as toner number variation coefficient)
Is calculated from the following equation.

Coefficient of variation in number of toner = [S ₂ / D _n ] × 1
00 (%) In the formula, S ₂ represents a standard deviation in the number particle size distribution, and D _n
Indicates a number average particle size (μm).

Effect of Coefficient of Variation of Number of Toner on the Present Invention The coefficient of variation of the number of toner used in the present invention is 27% or less, and 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 for a plurality of color toners used in the image forming apparatus of the present invention, the charging characteristics among the color toners can be made uniform, and the color generated when many sheets of the same color image are produced. The color shift of the image can be reduced. In addition, the surface of the photoreceptor on which the image of each color toner is formed also has a uniform number-average particle of each color toner, so that the surface deterioration of the photoreceptor becomes uniform.
The color misregistration of a color image generated when a large number of the same color images are produced can be reduced, and a uniform and good color image can be produced.

The method for controlling the number variation coefficient in the toner of the present invention 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 the size of toner particles. 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.

<Diameter of Toner Particles> The toner of the present invention preferably has a number average particle diameter of 3 to 8 μm. In the case where toner particles are formed by a polymerization method, the particle size is determined by the concentration of the coagulant, the amount of the organic solvent added, or the fusing time, and the composition of the polymer itself, in the toner manufacturing method described in detail below. Can be controlled by

When the number average particle diameter is from 3 to 8 μm, the amount of toner particles having a large adhesive force which adheres to the photoreceptor and causes filming is reduced, and the transfer efficiency is increased, so that the halftone image quality is reduced. The image quality of fine lines, dots, and the like is improved.

The toner used in the present invention has a natural logarithm lnD when the particle diameter of the toner particles is D (μm).
Is plotted on the horizontal axis, and in the histogram showing the number-based particle size distribution in which the horizontal axis is divided into a plurality of classes at intervals of 0.23, the relative frequency (m ₁ ) of the toner particles included in the most frequent class
It is preferable that the toner has a sum (M) of 70% or more of the relative frequency (m ₂ ) of the toner particles included in the class having the second highest frequency after the mode.

When the sum (M) of the relative frequency (m ₁ ) and the relative frequency (m ₂ ) is 70% or more, the dispersion of the particle size distribution of the toner particles is narrowed. By using this, 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 plotting the natural logarithm lnD (D: particle size of individual toner particles) in 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: 2.53 to 2.76...) Is a histogram showing the number-based particle size distribution, 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-1
1 (manufactured by Coulter Scientific Japan)
An appropriate amount of a surfactant (neutral detergent) is added to 50 to 100 ml, and the mixture is 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.

In the case of the pulverized toner, the shape factor is 1.2 to
The ratio of the 1.6 toner particles is about 60% by number. The variation coefficient of the shape factor is about 20%. In addition, the number variation coefficient in the number particle size distribution is about 30% when the classification operation after the pulverization is performed once, and the classification operation needs to be further repeated to reduce the number variation coefficient to 27% or less. There is.

In the case of the toner obtained by the suspension polymerization method, the toner is conventionally polymerized in a laminar flow, so that substantially spherical toner particles are obtained. For example, in the case of the toner described in JP-A-56-130762, The ratio of the toner particles having a coefficient of 1.2 to 1.6 is about 20% by number, and the variation coefficient of the shape coefficient is also about 18%. Further, as described above as a method for controlling the number variation coefficient in the number particle size distribution, mechanical shearing is repeated for a large oil droplet of a polymerizable monomer to reduce the oil droplet to a size of about a toner particle. Therefore, the distribution of oil droplet diameters is widened, and the particle size distribution of the obtained toner is wide, and the number variation coefficient is as large as about 32%. Therefore, a classification operation is required to reduce the number variation coefficient. .

Polymerized toners formed by associating or fusing resin particles are described in, for example,
In the toner described in JP-A-186253, the ratio of the toner particles having a shape coefficient of 1.2 to 1.6 is 60% by number.
And the variation coefficient of the shape factor is about 18%. Further, the particle size distribution of the toner is wide and the number variation coefficient is 30%, and a classification operation is required to reduce the number variation coefficient.

The particle diameter of the toner used in the present invention is preferably 3 to 8 μm in terms of volume average particle diameter. The volume average particle size and the particle size distribution of the toner are as follows: Coulter Counter TA-II,
It can be measured using a Coulter Multisizer, SLAD1100 (Shimadzu Corporation laser diffraction particle size analyzer) or the like. Aperture diameter = 100 for Coulter Counter TA-II and Coulter Multisizer
It is obtained by measuring the particle size distribution in the range of 2.0 to 40 μm using a μm aperture.

Further, the toner preferably has 30% by number or less of particles having a volume average particle diameter of less than 3.0 μm. The method for producing the toner is not particularly limited. In the pulverization classification method, pulverization may be performed while suppressing excessive pulverization during pulverization. Further, a method of repeatedly classifying may be employed. Further, as a method for producing a so-called polymerization toner, a method for producing a toner by a suspension polymerization method or a fusion method is also preferable.

Incidentally, the polymerization method can also be achieved by removing fine particles by centrifugation in a dispersion of resin particles, if necessary.

In any case, a pulverized toner or a polymerized toner satisfying the above requirements of the present invention,
The object of the present invention can be achieved.

<< Method of Manufacturing Toner Used in the Present Invention >>
The method for producing the toner used in the present invention is the most commonly used pulverization method, that is, a binder resin and a colorant,
It may be produced by kneading and pulverizing various additives to be added as required and then classifying, or may be produced by synthesizing and producing resin particles containing a release agent and a colorant in a medium.

As a method of fusing in an aqueous medium, for example, JP-A-63-186253, JP-A-63-2827
No. 49, JP-A-7-146583, and the like, and a method of salting out / fusing resin particles to form the resin particles.

The resin particles used herein preferably have a weight average particle size of 50 to 2,000 nm. These resin particles may be obtained by any granulation polymerization method such as emulsion polymerization, suspension polymerization, seed polymerization, etc., but are preferably used. Is an emulsion polymerization method.

Hereinafter, the monomers used for producing the resin are as follows:
In any of the production methods, a conventionally known polymerizable monomer can be used. In addition, one kind or a combination of two or more kinds can be used so as to satisfy required characteristics.

The binder resin is not particularly limited, and generally known binder resins such as a styrene resin, an acrylic resin, a styrene-acryl resin, a polyester resin, a styrene-butadiene resin, and an epoxy resin can be used. Can be used.

The resins constituting the styrene resin, the acrylic resin, and the styrene-acryl resin include styrene,
o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene,
3,4-dichlorostyrene, p-phenylstyrene, p
-Ethylstyrene, 2,4-dimethylstyrene, pt
-Butylstyrene, pn-hexylstyrene, pn
-Octyl styrene, pn-nonyl styrene, pn
Styrene or a styrene derivative such as -decylstyrene, pn-dodecylstyrene, methyl methacrylate,
Ethyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate,
Methacrylate derivatives such as lauryl methacrylate, phenyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, acrylic Acrylate derivatives such as isobutyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate, phenyl acrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, etc. These are listed as constituent monomers, and these can be used alone or in combination.

Examples of other specific compounds of vinyl polymers include olefins such as ethylene, propylene and isobutylene, and halogenated vinyls such as vinyl chloride, vinylidene chloride, vinyl bromide, vinyl fluoride and vinylidene fluoride. Vinyl esters such as vinyl propionate, vinyl acetate and 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 carbazole; N-vinyl compounds such as N-vinylindole and N-vinylpyrrolidone; vinyl compounds such as vinylnaphthalene and vinylpyridine; acrylonitrile, methacrylonitrile, acrylamide, N-butylacrylamide, N, N-dibutylacrylamide , Methacrylamide, N- methacrylamide, there are acrylic acid or methacrylic acid derivatives such as N- octadecyl acrylamide. These vinyl monomers can be used alone or in combination.

Examples of monomers for obtaining a carboxylic acid-containing polymer with a styrene-acrylic resin (vinyl resin) include acrylic acid, methacrylic acid, α-ethylacrylic acid, fumaric acid, maleic acid, itacone Acid, cinnamic acid, monobutyl maleate, monooctyl maleate, cinnamic anhydride, methyl alkenyl succinate half ester and the like.

Further, a crosslinking agent such as divinylbenzene, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, and triethylene glycol dimethacrylate may be added.

The polyester resin is a resin obtained by condensation-polymerizing a divalent or higher carboxylic acid and a divalent or higher alcohol component. Examples of divalent carboxylic acids include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutacoic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n- Dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, and the like can be used, and these acid anhydrides can also be used.

Examples of the dihydric alcohol component constituting the polyester resin include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl)
Propane, polyoxypropylene (3.3) -2,2-
Bis (4-hydroxyphenyl) propane, polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0)-
Etherified bisphenols such as polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, ethylene glycol, Diethylene glycol, triethylene glycol,
1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,4 butenediol, neopentyl glycol, 1,5-pentane glycol, 1,6-hexane glycol, 1,4- Examples thereof include cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, bisphenol Z, hydrogenated bisphenol A, and the like.

Examples of the polyester resin having a crosslinked structure include the following trivalent carboxylic acids, for example, 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4- Naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,
2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane,
1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, empole trimer acid and the like. Alternatively, a polyhydric alcohol component, specifically, sorbitol, 1,2,2
3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol,
1,2,5-pentatriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene and the like By adding it, a crosslinked polyester resin can be obtained.

Examples of the coloring agent include inorganic pigments and organic pigments. 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-described magnetite can be added. In this case, from the viewpoint of imparting predetermined magnetic characteristics, 20 to 6
It is preferable to add 0% by mass.

Conventionally known organic pigments can also be used. Specific organic pigments are exemplified below.

As pigments for magenta or red,
C. 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. I. Pigment Red 15, C.I. I. Pigment Red 16,
C. 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. Pigment red 144, C.I. I. Pigment Red 149, C.I. I. Pigment Red 166, 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. 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 94, C.I. I.
Pigment Yellow 138 and the like.

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

These organic 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.

The colorant can be used after surface modification. 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.

A so-called external additive can be added to the toner obtained in the present invention for the purpose of improving fluidity and cleaning property. These external additives are not particularly limited, and various inorganic fine particles,
Organic particulates and lubricants can be used.

Conventionally known inorganic fine particles can be used. Specifically, silica, titanium, alumina fine particles and the like can be preferably used. These inorganic fine particles are preferably hydrophobic. Specifically, as silica fine particles, for example, commercial products R-805, R-976, R-974, and R-97 manufactured by Nippon Aerosil Co., Ltd.
2, R-812, R-809, HVK- manufactured by Hoechst
2150, H-200, commercial product TS- manufactured by Cabot Corporation
720, TS-530, TS-610, H-5, MS-
5 and the like.

Examples of the titanium fine particles include commercially available products T-805 and T-604 manufactured by Nippon Aerosil Co., Ltd., and commercially available products MT-100S, MT-100B and MT-5 manufactured by Teika.
00BS, MT-600, MT-600SS, JA-
1. Commercial products TA-300SI, TA-
500, TAF-130, TAF-510, TAF-5
10T, commercial products IT-S, IT-OA manufactured by Idemitsu Kosan Co., Ltd.
IT-OB, IT-OC and the like can be mentioned.

Examples of the alumina fine particles include commercial products RFY-C and C-604 manufactured by Nippon Aerosil Co., Ltd., and commercial products TTO-55 manufactured by Ishihara Sangyo Co., Ltd.

As the organic fine particles, spherical organic fine particles having a number average primary particle diameter of about 10 to 2000 nm can be used. As this, a homopolymer such as styrene or methyl methacrylate or a copolymer thereof can be used.

Examples of the lubricant include salts of zinc, aluminum, copper, magnesium, calcium and the like of stearic acid, salts of zinc, manganese, iron, copper and magnesium of oleic acid, and zinc, copper, magnesium and calcium of palmitic acid. Metal salts of higher fatty acids such as salts of linoleic acid such as zinc and calcium, and salts of ricinoleic acid such as zinc and calcium.

The addition amount of these external additives is preferably about 0.1 to 5% by mass based on the toner. In the toner-forming step, the above-mentioned external additive may be added to the toner particles obtained above for the purpose of improving, for example, fluidity, chargeability, and cleaning properties. As a method of adding the external additive, various known mixing devices such as a Turbula mixer, a Henschel mixer, a Nauter mixer, and a V-type mixer can be used.

The toner may contain, in addition to the binder resin and the colorant, a material capable of imparting various functions as a toner additive. Specific examples include a release agent and a charge control agent.

The release agent may be any of a variety of known ones. Specific examples include olefin waxes such as polypropylene and polyethylene, modified products thereof, natural waxes such as carnauba wax and rice wax, and fatty acids. Examples include amide waxes such as bisamide. It has already been mentioned that these are preferably added as release agent particles and are preferably salted out / fused together with the resin or colorant.

The charge control agents are also various known ones.
What can be dispersed in water can also be used. Specifically, nigrosine dyes, metal salts of naphthenic acid or higher fatty acids, alkoxylated amines,
Quaternary ammonium salt compounds, azo-based metal complexes, salicylic acid metal salts or metal complexes thereof.

<< Developer >> The toner used in the present invention is:
Although it may be used as a one-component developer or a two-component developer,
Preferably as a two-component developer.

When the toner is used as a one-component developer, there is a method in which the toner is used as it is as a non-magnetic one-component developer. However, usually, magnetic particles having a particle size of about 0.1 to 5 μm are contained in the toner particles. Used as a developer. As a method of containing the same, it is common to make the non-spherical particles contain the same as the coloring agent.

Further, it can be used as a two-component developer by mixing with a carrier. In this case, as the magnetic particles of the carrier, conventionally known materials such as metals such as iron, ferrite and magnetite, and alloys of these metals with metals such as aluminum and lead are used. Particularly, ferrite particles are preferable. The magnetic particles have a volume average particle size of 15
-100 μm, more preferably 25-60 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 known resins can be used.For example, styrene acrylic resin, polyester resin, fluorine resin, phenol resin, and the like can be used. it can.

Next, the photosensitive member used in the present invention will be described in detail. In the image forming apparatus using the intermediate transfer member of the present invention, since the color toner image on the surface of the photoconductor is overlapped on the intermediate transfer member, it is easily affected by the surface deterioration of the photoconductor. In the image forming apparatus of the present invention, by using a resin layer having a large resistance to abrasion as described below for the surface layer of the photoreceptor, the surface deterioration of the photoreceptor is reduced, and the image forming apparatus of the present invention is used. Image quality degradation can be reduced. That is, in the electrophotographic photoreceptor of the present invention, the film thickness loss per rotation ΔHd (μm) is 0 ≦ ΔH
d <5 × 10 ⁻⁵ .

The thickness loss amount ΔHd (under normal temperature and normal humidity environment (20
° C, 50% RH)) In the present invention, the measurement of the thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member is a value obtained by performing the following abrasion test.

Abrasion test Under normal temperature and normal humidity (20 ° C., 50% RH), the electrophotographic photosensitive member connected to the drive unit has a hardness of 70 ± 1 ° and a rebound resilience of 35 ± 1.
%, A thickness of 2 ± 0.1 (mm), and a free blade of 9 ± 0.1 mm with a contact angle of 10 ± in the counter direction.
0.5 °, biting amount 1.5 ± 0.2 (mm) abuts on the electrophotographic photoreceptor while rotating the electrophotographic photoreceptor by a drive unit at a rotation of 0.1 to 10 seconds per rotation. 0.
A powder having a bulk density of 0.41 ± 0.1 g / cm ³ and a number average particle diameter of 10 to 40 (nm) developed with an adhesion amount of 15 ± 0.05 (mg / cm ² ) is an external additive. The toner having a volume average particle diameter of 8.5 ± 0.2 μm mixed at 1 ± 0.1 mass (%) with respect to the toner is cleaned. The amount of change in the thickness of the photoconductor when the electrophotographic photoconductor was rotated 100,000 times or more under the above conditions was measured, and the value obtained by dividing the value by the number of rotations of the photoconductor was used as the value per rotation. It is assumed to be the thickness loss.

In the present invention, the film thickness loss per rotation Δ
Hd (μm) is 0 ≦ ΔHd <1 × 10 ⁻⁵ , preferably 0 ≦ ΔHd <5 × 10 ⁻⁶ , more preferably 0 ≦ ΔH.
d <3 × 10 ⁻⁶ .

FIG. 1 is an explanatory view of the contact condition of the cleaning blade to the photosensitive member in the abrasion test.

In FIG. 1, the electrophotographic photosensitive member is represented by 1, and the contact angle is represented by θ. The free length L of the cleaning blade 2 represents the length of the tip of the blade before deformation from the end B of the support member 3 as shown in FIG.

Reference numeral 4 denotes a fixing screw for fixing the support member 3. h indicates the thickness of the blade.

The contact angle θ is the angle between the tangent line X at the contact point A of the photosensitive member and the blade before deformation (shown by a dotted line in the drawing).

Further, as shown in FIG. 1, the bite amount a is the central axis of the photosensitive member having one point as the radius r ₀ of the outer periphery S ₀ of the photosensitive member and the position A ′ of the blade before deformation (indicated by a dotted line in the drawing). This is the difference from the radius r ₁ of the circle S ₁ centered on C.

The physical property values of the elastic rubber blade used for the cleaning blade;
The hardness and the rebound resilience are measured based on JIS K6301 vulcanized rubber physical test method.

The amount of toner attached is the mass (mg) of toner per 1 cm ² developed on the surface of the photoreceptor by bias development from a developing unit. In the abrasion test of the present invention, the unit area removed by a cleaning blade is used. Per toner amount.

The amount of toner adhered is determined by transferring the toner developed and adhered to the surface of the photoreceptor onto an adhesive tape, calculating the mass difference of the adhesive tape before and after the toner transfer, and converting it to about 1 cm ² .

<< Specific Example of Measurement of Depletion of Film Thickness in the Present Invention >> A specific example of measurement of loss of thickness in the present invention will be described below. An abrasion tester having only a developing unit and a cleaning unit was manufactured by modifying a digital copying machine Konica 7040 manufactured by Konica Corporation. A cleaning blade having a hardness of 70 °, a rebound resilience of 35%, a thickness of 2 (mm) and a free length of 9 mm was brought into contact with the cleaning portion in the counter direction at a contact angle of 10 ° and a bite amount of 1.5 (mm). Next, while rotating the cylindrical electrophotographic photosensitive member having a diameter of 60 mm at a linear velocity of 210 (mm / sec), a zero voltage is applied on the electrophotographic photosensitive member by utilizing a potential difference between a bias potential of the developing section and a photosensitive member connected to the ground. .
Development is performed with a toner adhesion amount of 15 ± 0.05 (mg / cm ² ). As the toner and the developer, the following developers for evaluation were used. Under normal temperature and normal humidity environment (20 ° C, 50% R
H) The electrophotographic photoreceptor is rotated 1,000,000 times, and the film thickness variation (difference from the initial film thickness) of the photoreceptor when the development-cleaning process is repeated is measured. The value obtained by dividing the number of rotations of the photoreceptor was defined as the thickness loss per rotation.

Preparation of developer for evaluation 100 parts of styrene acrylic resin having a mass ratio of styrene: butyl acrylate: butyl methacrylate = 75: 20: 5, 10 parts of carbon black, 4 parts of low molecular weight polypropylene (number average molecular weight = 3500) Were melted and kneaded, and then finely pulverized using a mechanical pulverizer and classified to obtain colored particles having a volume average particle size of 8.5 μm.

[0112] Hydrophobic silica particles having an average particle diameter of 12 nm
And 0.6 part of titania particles having an average particle size of 30 nm were mixed at room temperature with a Henschel mixer at a peripheral speed of the stirring blade of 40 parts.
(M / sec) for 10 minutes to obtain a negatively chargeable toner. The bulk density of the toner was 0.41 g / cm ³ .

A ferrite carrier coated with a silicone resin and having a volume average particle diameter of 60 μm was mixed with the toner to prepare a developer having a toner concentration of 5%.

Measurement of bulk (apparent) density: The apparent density is measured using a powder tester (manufactured by Hosokawa Micron).

For the measurement, a 60-mesh screen is set on a vibrating table, and a cup for measuring the apparent density (content: 100 ml) whose mass has been measured in advance is placed immediately below the screen. Next, the rheostat scale is adjusted to 2.0 and vibration is started.
The measurement sample is gently discharged from the vibrating top of the 60-mesh screen so as to enter the measurement cup.

When the cup is filled with the heaping sample, the vibration is stopped, the upper surface of the heaping cup is abraded by a blade, and the balance is accurately weighed by a balance.

Since the measuring cup has a content of 100 ml, the apparent density (g / cm ³ ) = the mass of the sample ÷ 1
00 can be obtained.

The sample was prepared for about 1 hour at 20 ° C. and 50% RH.
The measurement environment was 20 ℃, 50%
RH.

* Thickness Measurement Method The thickness of the photosensitive layer is measured at random at 10 locations of uniform thickness, and the average value is defined as the thickness of the photosensitive layer. The film thickness measuring device is an eddy current type film thickness measuring device EDDY560C (HELMUT
FISCHER GMBTE CO).

The structure of the 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 cylindrical conductive support is used. Is more preferred.

The cylindrical conductive support means a cylindrical support necessary for forming an image endlessly by rotating, and has a straightness of 0.1 mm or less and a run-out of 0.1 mm.
Conductive supports in the following ranges 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 / 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.

In the present invention, “having at least a plurality of resin layers on the cylindrical conductive support” means that two or more layers in which the resin has a main function of forming a layer are formed on the cylindrical conductive support. This means that the resin layer may have at least two layers of a subbing layer, a photosensitive layer, a surface layer, a charge generation layer, a charge transport layer and the like.

The preferred layer structure of the electrophotographic photosensitive member of the present invention will be described below. Undercoat Layer The undercoat layer (UCL) used in the photoreceptor of the present invention is used to improve the adhesion between the conductive support and the photosensitive layer or to prevent charge injection from the support. Is provided between the photosensitive layer, the material of the undercoat layer, polyamide resin, vinyl chloride resin, vinyl acetate resin,
Copolymer resins containing two or more of the repeating units of these resins are exemplified. Among these undercoat 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 undercoat layer using these resins is preferably 0.01 to 0.5 μm.

The undercoat layer most preferably used in the present invention is an undercoat layer using a curable metal resin obtained by thermosetting an organic metal compound such as a silane coupling agent or a titanium coupling agent. The thickness of the undercoat 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 undercoat layer, but more preferably. It is preferable that the function of the photosensitive layer is separated into a charge generation layer (CGL) and a charge transport layer (CTL layer). 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. It is preferable that the photoreceptor for negative charging has a configuration in which a charge generation layer (CGL) is provided on the undercoat layer, and a charge transport layer (CTL layer) is provided 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 structure 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 substance (CGM), a known charge generating substance (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 between 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 silicon-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 layer) include polystyrene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, polyvinyl butyral resin, epoxy resin, polyurethane resin,
Phenolic resin, polyester resin, alkyd resin,
A polycarbonate resin, a silicon resin, a melamine resin, and a copolymer resin containing two or more of 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. 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.

Surface Layer (Surface Layer Containing Siloxane Resin Having Charge Transporting Performance) The electrophotographic photoreceptor of the present invention having a high hardness and a small increase in residual potential is a siloxane resin containing a structural unit having charge transporting properties. A photoreceptor having a resin layer containing a surface layer as a surface layer is preferred. The siloxane-based resin layer is typically formed by applying and drying a coating composition using an organosilicon compound represented by the following general formula (1) as a raw material. These raw materials form a condensate (oligomer) of an organosilicon compound in a hydrophilic solvent by hydrolysis and a subsequent condensation reaction. By coating and drying these coating compositions, a resin layer containing a siloxane-based resin having a three-dimensional network structure can be formed.

Formula (1) (R) _n -Si- (X) _{4-n In the} formula, R represents an organic group in which carbon is directly bonded to a silicon atom, and X represents a hydroxyl group or a hydrolyzable group. And n is 0 to
Represents an integer of 3.

In the organosilicon compound represented by the general formula (1), the organic group in which carbon represented by R is directly bonded to silicon includes alkyl groups such as methyl, ethyl, propyl and butyl, phenyl and tolyl. , Naphthyl, aryl groups such as biphenyl, γ-glycidoxypropyl, β-
Epoxy-containing groups such as (3,4-epoxycyclohexyl) ethyl, (meth) acryloyl groups such as γ-acryloxypropyl and γ-methacryloxypropyl, γ-hydroxypropyl and 2,3-dihydroxypropyloxypropyl Hydroxyl groups, vinyl, vinyl-containing groups such as propenyl, mercapto-containing groups such as γ-mercaptopropyl, γ-
Amino-containing groups such as aminopropyl and N-β (aminoethyl) -γ-aminopropyl; γ-chloropropyl;
Examples include a halogen-containing group such as 1,1-trifluorofluoropropyl, nonafluorohexyl, and perfluorooctylethyl, and other nitro and cyano-substituted alkyl groups. Particularly, an alkyl group such as methyl, ethyl, propyl, and butyl is preferable. Examples of the hydrolyzable group for X include an alkoxy group such as methoxy and ethoxy, a halogen group, and an acyloxy group. Particularly, an alkoxy group having 6 or less carbon atoms is preferable.

The organosilicon compounds represented by the general formula (1) may be used alone or in combination of two or more. However, it is preferable that at least one of the organosilicon compounds represented by the general formula (1) used is an organosilicon compound in which n is 0 or 1.

When n is 2 or more in the specific compound of the organosilicon compound represented by the general formula (1), a plurality of Rs may be the same or different. Similarly, when n is 2 or less, a plurality of Xs may be the same or different. When two or more organosilicon compounds represented by the general formula (1) are used, R and X may be the same or different between the respective compounds.

The resin layer is preferably formed by adding colloidal silica to a composition containing the above-mentioned organosilicon compound or a hydrolytic condensate thereof. Colloidal silica is silicon dioxide particles dispersed in a colloidal form in a dispersion medium. Colloidal silica may be added at any stage of adjusting the composition of the coating solution. Colloidal silica may be added in the form of an aqueous or alcoholic sol,
The aerosol formed in the gas phase may be directly dispersed in the coating solution of the present invention.

In addition, metal oxides such as titania and alumina may be added in the form of sol or particles.

The colloidal silica or the tetrafunctional (n = 0) or trifunctional (n = 1) organosilicon compound gives the resin layer film of the present invention elasticity and rigidity by forming a crosslinked structure. When the ratio of the bifunctional organosilicon compound (n = 2) increases, the rubber elasticity increases and the hydrophobicity increases.
The functional organosilicon compound (n = 3) does not become a polymer, but has a function of increasing hydrophobicity by reacting with unreacted residual SiOH groups.

As the surface layer of the present invention, which is required to have high hardness and high elasticity, a tetrafunctional (n =
It is preferable to form a siloxane-based resin layer having elasticity and rigidity by using at least one of 0) and trifunctional (n = 1) as a raw material.

The resin layer further contains a siloxane-based resin containing a structural unit having a charge transporting property by a condensation reaction of the compound represented by the following general formula (2) with the organosilicon compound or the condensate thereof. By modifying the resin layer, an increase in the residual potential of the resin layer can be suppressed.

Formula (2) B- (R₁-ZH)_m In the formula, B is a monovalent or monovalent compound containing a structural unit having charge transporting performance
Represents a polyvalent group; ₁Is a single bond or divalent alkylene
Z represents an oxygen atom, a sulfur atom or NH;
Represents an integer of 1 to 4.

The compound represented by the general formula (2) is subjected to a condensation reaction with a hydroxyl group on the surface of colloidal silica,
It may be incorporated in the siloxane-based resin layer.

In the present invention, a siloxane-based ceramic resin layer formed by adding a metal hydroxide other than colloidal silica (for example, a hydrolyzate of each alkoxide of aluminum, titanium and zirconium) may be used.

In the general formula (2), B is a charge-transporting compound structure
And a monovalent or higher group. Where B is a charge transport compound
Including the compound structure means that (R) in the general formula (2)₁—ZH) group
Whether the compound structure except for has charge transport performance, or
Is (R) in the general formula (2). ₁-ZH) group by a hydrogen atom
Means that the substituted BH compound has charge transport performance
I do.

The above-mentioned charge transporting compound is a compound having a property of having electron or hole drift mobility. Another definition is Time-Of-Flight.
It can be defined as a compound capable of obtaining a detection current due to charge transport by a known method capable of detecting charge transport performance such as a method.

The total amount (H) of the organosilicon compound having a hydroxyl group or a hydrolyzable group and the condensate formed from the organosilicon compound having a hydroxyl group or a hydrolyzable group, and the compound of the formula (2) The composition ratio in the composition (I) is preferably 100: 3 to 50: 100, more preferably 100: 10 to 50:10 by mass ratio.
It is between 0.

In the present invention, colloidal silica or another metal oxide may be added. However, when colloidal silica or another metal oxide (J) is added, the total amount (H) + the compound (I) It is preferable to use 1 to 30 parts by mass of (J) based on 100 parts by mass of the total component.

When the total amount (H) is used in the above range, the surface layer of the photosensitive member of the present invention has high hardness and elasticity. Excess or deficiency of the colloidal silica component (J) has the same tendency as the total amount (H). on the other hand,
When the compound (I) is used in the above range, the electrophotographic characteristics such as sensitivity and residual potential characteristics are good, and the hardness of the photoconductor surface layer is high.

For forming the siloxane-based resin layer, it is preferable to use a condensation catalyst in order to accelerate the condensation reaction. The condensation catalyst used here may be a catalyst that has at least one of a catalyst that acts in contact with the condensation reaction and a catalyst that acts to shift the reaction equilibrium of the condensation reaction to the production system.

As a specific condensation catalyst, a known catalyst conventionally used for a silicon hard coat material, such as an acid, a metal oxide, a metal salt, and an alkylaminosilane compound can be used. For example, organic carboxylic acids, nitrous acid,
Alkali metal salts of sulfurous acid, aluminate, carbonic acid and thiocyanic acid, organic amine salts (tetramethylammonium hydroxide, tetramethylammonium acetate), tin organic acid salts (stannas octoate, dibutyltin diacetate, dibutyltin dilaurate, dibutyl) Timmercaptide, dibutyltin thiocarboxylate, dibutyltin malate and the like.

In the general formula (2), the group having a charge transporting compound structure represented by B includes a hole transport type and an electron transport type. The hole transport type is oxazole, oxadiazole, thiazole, triazole, imidazole,
Groups containing structural units such as imidazolone, imidazoline, bisimidazolidine, styryl, hydrazone, benzidine, pyrazoline, triarylamine, oxazolone, benzothiazole, benzimidazole, quinazoline, benzofuran, acridine, phenazine and groups derived from these derivatives. Is mentioned. On the other hand, the electron transport type includes succinic anhydride, maleic anhydride, phthalic anhydride, pyromellitic anhydride, melitic anhydride, tetratocyanoethylene, tetratocyanoquinodimethane, nitrobenzene, dinitrobenzene, trinitrobenzene, tetranitrobenzene, and nitrobenzene. Benzonitrile, picryl chloride,
Quinone chlorimide, chloranil, bromanyl, benzoquinone, naphthoquinone, diphenoquinone, tropoquinone, anthraquinone, 1-chloroanthraquinone, dinitroanthraquinone, 4-nitrobenzophenone, 4,
4'-dinitrobenzophenone, 4-nitrobenzalmalone dinitrile, α-cyano-β- (p-cyanophenyl) -2- (p-chlorophenyl) ethylene, 2,7-
Dinitrofluorenone, 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitrofluorenone,
9-fluoronylidenedicyanomethylenemalonitrile,
Polynitro-9-fluoronylidenedicyanomethylenemalonitrile, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, 3,5-dinitrobenzoic acid, perfluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitro Examples include groups containing chemical structural units such as salicylic acid, phthalic acid and melitic acid, and groups derived from derivatives thereof, but are not limited to these structures.

Examples of typical compounds represented by the general formula (2) are shown below. Examples of compounds in which Z is an oxygen atom in the general formula (2) are shown below.

[0157]

Embedded image

[0158]

Embedded image

[0159]

Embedded image

[0160]

Embedded image

[0161]

Embedded image

Next, examples of the compound of the formula (2) in which Z is an NH group are shown below.

[0163]

Embedded image

Next, examples of the compound in which Z is a mercapto group (SH) in the general formula (2) are shown below.

[0165]

Embedded image

Among the compounds represented by the following formula (2), the most preferred compounds are those wherein Z is a hydroxyl group (OH) and m is 2 or more. A compound in which Z is a hydroxyl group (OH) and m is 2 or more is a resin layer having high hardness and a small increase in residual potential due to the compound reacting with the organosilicon compound and penetrating into the network structure of the siloxane-based resin. Can be formed.

Although the most preferred layer configuration of the photoreceptor of the present invention has been described above, other layer configurations of the photoreceptor may be used in the present invention. For example, if a resin layer containing a siloxane-based resin containing a structural unit having a charge transporting property is applied to the charge transporting layer, the above-described surface layer of the photoconductor layer can be removed. Further, when a resin layer containing a siloxane-based resin containing a structural unit having a charge transporting property is applied to a photosensitive layer having a single-layer structure, an undercoat layer and a photosensitive layer having a single-layer structure are formed on a cylindrical conductive support. The electrophotographic photoreceptor of the present invention can be formed from two resin layers.

The surface layer of the electrophotographic photosensitive member of the present invention preferably has a water contact angle of 90 ° or more. By setting the contact angle with water to 90 ° or more, filming of paper powder and toner fine powder can be further reduced.

As a method for setting the contact angle of water to the siloxane-based resin layer having the charge transporting property of 90 ° or more, it is effective to increase the hydrophobicity of the siloxane resin layer. As a method for this, a method of introducing an F atom-containing group into the siloxane resin, a method of introducing a dimethylsiloxane skeleton, a method of introducing an aromatic group, or a method of adding resin particles or an organic polymer having water repellency such as PTFE. And the like.

Next, examples of the organic fine particles and inorganic fine particles which can be used together with the above-mentioned colloidal silica in the resin layer of the present invention or can be used in place of the co-idal silica are as follows.

<Organic Fine Particles> As the above organic fine particles,
For example, silicone resin, polytetrafluoroethylene,
Polyvinylidene fluoride, Polyethylene trifluoride chloride, Polyvinyl fluoride, Polytetrafluoroethylene-perfluoroalkylvinyl ether copolymer, Polytetrafluoroethylene-propylene hexafluoride copolymer, Polyethylene-trifluoroethylene copolymer Polymer, polytetrafluoroethylene-hexafluoropropylene-perfluoroalkylvinyl ether copolymer, polyethylene, polyvinyl chloride, metal stearate, polymethyl methacrylate or melamine, etc. It is preferably from 0.05 to 10 μm, more preferably from 0.1 to 5 μm. or,
The amount of the organic fine particles contained in the resin layer of the present invention is preferably 0.1 to 100 with respect to the binder resin of the resin layer.
% By mass, more preferably 1 to 50% by mass,
%, Sufficient printing durability and lubricity cannot be imparted to the photosensitive layer, which tends to cause poor cleaning during image formation, and does not improve the adhesion to the lower layer. If it exceeds 100% by mass, the photosensitivity of the photoreceptor decreases, and fogging is likely to occur.

<Inorganic Fine Particles> As the inorganic fine particles, metal oxides such as magnesium oxide, calcium oxide, titanium oxide, zirconium oxide, tin oxide, aluminum oxide, silicon oxide (silica), indium oxide, beryllium oxide, and lead oxide , Bismuth oxide, etc., and the nitrides include, for example, boron nitride, aluminum nitride, and silicon nitride. The carbides include, for example, silicon carbide, boron carbide, and the like. The inorganic fine particles may be preferably subjected to a hydrophobic treatment with a hydrophobic treatment agent such as a titanium coupling agent, a silane coupling agent, an aluminum coupling agent, or a high-molecular fatty acid.

The particle diameter of the above-mentioned inorganic fine particles is preferably from 0.05 to 10 μm in terms of volume average particle diameter, more preferably from 0.1 to 10 μm.
1 to 5 μm. Further, the amount of the inorganic fine particles contained in the photoconductor surface layer, the binder resin of the surface layer,
Preferably 0.1 to 100% by mass, more preferably 1 to 100% by mass.
When the amount is 50% by mass and less than 0.1%, sufficient printing durability, mechanical strength, or adhesiveness with the lower layer cannot be imparted to the surface layer of the photoreceptor, and the surface layer of the photoreceptor is not formed during image formation. However, if it exceeds 100% by mass, the surface roughness of the photoreceptor surface layer becomes large, and the cleaning member is damaged to cause poor cleaning.

The volume average particle diameter of the organic fine particles and the inorganic fine particles is measured by a laser diffraction / scattering type particle size distribution analyzer “LA-700” (manufactured by Horiba, Ltd.).

By adding an antioxidant to the surface layer of the siloxane-based resin, it is possible to effectively prevent a rise in residual potential and image blur.

Here, the antioxidant is a typical antioxidant that reacts with an autoxidizable substance present in the electrophotographic photoreceptor or on the surface of the photoreceptor under the conditions of light, heat, discharge and the like. It is a substance having the property of preventing or suppressing the action. Specifically, the following compounds may be mentioned.

(1) Radical chain inhibitor • Phenolic antioxidant (hindered phenol) • Amine antioxidant (hindered amine, diallyldiamine, diallylamine) • Hydroquinone antioxidant (2) Peroxidation Decomposers ・ Sulfur antioxidants (thioethers) ・ Phosphoric antioxidants (phosphites) Among the above antioxidants, the radical chain inhibitor of (1) is preferable, and particularly hindered phenol or Hindered amine antioxidants are preferred. Further, two or more kinds may be used in combination, for example, a combination of the hindered phenol antioxidant (1) and the thioether antioxidant (2) may be used. Further, a molecule containing the above structural unit, for example, a hindered phenol structural unit and a hindered amine structural unit in a molecule may be used.

Among the above antioxidants, hindered phenol-based and hindered amine-based antioxidants are particularly effective in preventing fogging and image blurring at high temperature and high humidity.

The content of the hindered phenol or hindered amine antioxidant in the resin layer is from 0.01 to 2
0% by mass is preferred. When the content is less than 0.01% by mass, there is no effect on fogging and image blur at high temperature and high humidity, and when the content is more than 20% by mass, the charge transport ability in the resin layer is reduced, and the residual potential tends to increase, In addition, a decrease in film strength occurs.

The antioxidant may be contained in the lower charge generation layer, charge transport layer, intermediate layer and the like, if necessary. The amount of the antioxidant added to these layers is preferably 0.01 to 20% by mass with respect to each layer.

Here, the hindered phenol refers to compounds having a branched alkyl group at an ortho position to the hydroxyl group of the phenol compound and derivatives thereof (however, the hydroxyl group may be modified to alkoxy).

A hindered amine compound is a compound having a bulky organic group near an N atom. As the bulky organic group, there is a branched alkyl group, and for example, a t-butyl group is preferable. For example, compounds having an organic group represented by the following structural formula are preferable.

[0183]

Embedded image

In the formula, R ₁₃ is a hydrogen atom or a monovalent organic group,
R ₁₄ , R ₁₅ , R ₁₆ and R _{17 each} represent an alkyl group, and R ₁₈ represents a hydrogen atom, a hydroxyl group or a monovalent organic group.

Examples of the antioxidant having a hindered phenol partial structure include, for example, JP-A-1-118137 (P.
7 to P14), but the present invention is not limited thereto.

Examples of the antioxidant having a hindered amine partial structure include, for example, JP-A-1-118138 (P7-
The compounds described in P9) may also be mentioned, but the present invention is not limited thereto.

As the organic phosphorus compound, for example, there are the following compounds represented by the general formula RO-P (OR) -OR. Here, R represents a hydrogen atom, a substituted or unsubstituted alkyl group, alkenyl group or aryl group.

As the organic sulfur-based compound, for example, the following compounds are representative of the compounds represented by the general formula RSR. Here, R represents a hydrogen atom, a substituted or unsubstituted alkyl group, alkenyl group or aryl group.

The following are examples of typical antioxidant compounds.

[0190]

Embedded image

[0191]

Embedded image

[0192]

Embedded image

[0193]

Embedded image

The following compounds are commercially available antioxidants, such as “Irganox 1076” and “Irganox 1” as hindered phenol compounds.
010 "," Ilganox 1098 "," Ilganox 245 "," Ilganox 1330 "," Ilganox 3114 "," Ilganox 1076 ",
"3,5-di-t-butyl-4-hydroxybiphenyl" and "Sanol LS262
6, "Sanol LS765", "Sanol LS77"
0 "," Sanol LS744 "," Tinuvin 144 ",
“Tinuvin 622LD”, “Mark LA57”, “Mark LA67”, “Mark LA62”, “Mark LA6”
8 "and" Mark LA63 ", and as thioethers," Sumilyzer-TPS "and" Sumilyzer TP-
D ", and as a phosphite system," Mark 211 "
2, "Mark PEP-8", "Mark PEP-24"
G "," Mark PEP-36 "," Mark 329K ",
"Mark HP-10".

In order to form a layer containing the siloxane-based resin of the present invention, the siloxane-based resin composition is usually dissolved in a solvent and applied. Methanol as a solvent,
Alcohols such as ethanol, propanol, butanol, methyl cellosolve and ethyl cellosolve and derivatives thereof; ketones such as methyl ethyl ketone and acetone; esters such as ethyl acetate and butyl acetate are used.

The siloxane-based resin layer of the present invention is preferably dried by heating. The heating promotes the crosslinking / curing reaction of the siloxane-based resin layer. The cross-linking and curing conditions vary depending on the type of solvent used and the presence or absence of a catalyst.
Heating in the range of 0 to 160 ° C for 10 minutes to 5 hours is preferable, and more preferably in the range of 90 to 120 ° C for 30 minutes to 2 hours.
Time heating is preferred.

Solvents used for dispersing and dissolving the charge generating substance and the charge transporting substance include hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as methylene chloride and 1,2-dichloroethane; methyl ethyl ketone and cyclohexanone. Ketones; esters such as ethyl acetate and butyl acetate; alcohols such as methanol, ethanol, methyl cellosolve and ethyl cellosolve and derivatives thereof; tetrahydrofuran, 1,4-dioxane and 1,3
Ethers such as dioxolane; amines such as pyridine and diethylamine; amides such as N, N-dimethylformamide; other fatty acids and phenols; one or two of sulfur and phosphorus compounds such as carbon disulfide and triethyl phosphate; More than one species can be used.

As a coating method for producing the electrophotographic photosensitive member having the surface layer, a dip coating, a spray coating, a circular amount control type coating, or the like of a coating solution can be used. In particular, in the coating process on the surface layer side of the photosensitive layer, spray coating or circular amount control type coating (a typical example is a circular slide hopper) is used to dissolve the lower layer film as much as possible and to achieve uniform coating process. Is preferred. The spray coating is described in JP-A-3-90250 and JP-A-3-269238, and the details of the circular amount control type coating are described in JP-A-58-189061.

Next, each means used in the image forming apparatus of the present invention will be described with reference to examples. (However, the image forming apparatus does not need to include all of these units, and may be appropriately composed of some of these units depending on the intended image forming apparatus.) Exposure for erasing the charge remaining on the photoreceptor during the formation): Light irradiation by an LED or the like is used as the pre-charging exposure means. Exposure before charging can suppress an increase in the residual potential due to a delay in the response of the photoreceptor and the occurrence of memory due to the exposure pattern. However, in the image forming apparatus of the present invention, the pre-charging exposure unit is not always necessary.

Charging means: Any of corona charging and contact charging methods can be suitably used. The charging potential on the photoreceptor is appropriately determined depending on the photoreceptor to be used, but is charged by this charging means so that the charging voltage becomes 300 to 1500 V.

Image exposure means: exposure light source is white light, LE
Both D and LD can be suitably used. In the case of a digital image, the image exposure light source is preferably an LED or LD.

Developing means: One-component and two-component developers can be used for the developing means, and both magnetic and non-magnetic toners can be suitably used. Further, contact development in which the photoconductor and the developer are in contact with each other or non-contact development in the opposite direction may be used.

Transfer means: As the transfer means, any of corona transfer, roller transfer, and transfer method using an intermediate transfer member is suitably used.

Cleaning means: Usually, a cleaning blade is suitably used, and a fur brush or a roller can be used as an auxiliary member for cleaning.
Since the cleaning conditions greatly affect the wear of the photoreceptor, the use of the electrophotographic photoreceptor of the present invention can support a wide range of cleaning means.

Next, a description will be given of the cleaning means which has an important relation to the thickness reduction of the photoreceptor in the present invention such as the photoreceptor thickness reduction and filming among the image forming units.

Cleaning blade characteristics and contact conditions In the present invention, using a device provided with a blade-like cleaning member arranged in pressure contact with the photoreceptor to clean toner remaining on the photoreceptor without being transferred. preferable. The contact condition of the cleaning blade to the photoreceptor is preferably from 5 to 50 g / cm in pressure from the viewpoint of improving the cleaning property. If the pressing force is less than 5 g / cm, the toner tends to slip through, and the pressing force is 50 g / cm.
If it is larger than cm, blade scraping easily occurs.

In the stage prior to the cleaning means, a charge removing means for removing the charge on the surface of the photoreceptor may be added to facilitate the cleaning. This static elimination means is performed by, for example, a static eliminator that generates an AC corona discharge.

The cleaning blade used in the present invention has a hardness of 65 ° to 75 ° and a rebound resilience of 15% to 60%.
A rubber elastic body (under conditions of 20 ° C. and 50 ± 5% RH) is preferable. If the rebound resilience is less than 15%, the blade tends to be bound easily, and it is difficult to ensure the cleaning property in a low temperature environment. If the resilience exceeds 75%, the followability of the blade is increased, and the blade is more likely to be scraped ( Physical properties of the elastic rubber blade used for the cleaning blade; hardness and rebound resilience are measured as JISA hardness and rebound resilience based on JIS K6301 vulcanized rubber physical test method).

As the cleaning blade used in the present invention, silicon rubber, urethane rubber or the like is used, but one made of urethane rubber is most preferable.

In an image forming apparatus using an intermediate transfer member (also referred to as an intermediate transfer means) of the present invention, a color image is formed by superimposing a color toner on the intermediate transfer member, and then a transfer material (transfer paper, recording paper) is formed. , Which is also referred to as a recording material).

The structure of the intermediate transfer member is generally a multilayer structure. For example, an elastic layer formed of at least rubber, an elastomer, a resin, etc., on a conductive support,
And a structure provided with at least one coating layer. The shape of the intermediate transfer member is not particularly limited and can be appropriately selected depending on the purpose.
A roller shape, a belt shape, and the like are preferably exemplified.

As the material of the intermediate transfer member, for example,
Conductive carbon particles and metal powder for polyurethane resin, polyester resin, polystyrene resin, polyolefin resin, polybutadiene resin, polyamide resin, polyvinyl chloride resin, polyethylene resin, fluorine resin, etc. And the like are preferably used. Among these, those obtained by dispersing carbon particles in a polyurethane resin can be suitably used.

The surface volume resistance of the intermediate transfer member is preferably, for example, 10 ⁸ to 10 ¹⁶ Ωcm. If the surface volume resistance value is less than 10 ⁸ Ωcm, bleeding or thickening occurs in the image, and if it exceeds 10 ¹⁶ Ωcm, scattering of the image occurs, and the need for static elimination of the intermediate transfer body sheet occurs.
Either case is not preferred. The thickness of the intermediate transfer member is preferably, for example, about 50 to 200 μm.

FIG. 2 is a sectional view showing the structure of the color image forming apparatus of the present invention. This embodiment is an image forming apparatus for forming a color toner image on a transfer material.

Around the photosensitive drum 21 rotating clockwise as indicated by the arrow, a charging unit 22, an exposure unit 23 using a laser as a light source, a yellow developing unit 24Y, a magenta developing unit 24M, a cyan developing unit 24C, and a black developing unit Means 24K
And a cleaning unit 25. An intermediate transfer member 10 including a conductive base 61 made of a metal drum and a layer 62 containing a conductive metal oxide of the present invention is arranged in contact with the photoreceptor drum 21. A transfer voltage is applied to a conductive substrate 61 of the intermediate transfer member by a power supply 63. A transfer roller 65 for transferring the toner image on the intermediate transfer member 10 to a transfer material is disposed substantially immediately below the transfer position of the toner image from the photosensitive drum 21 to the intermediate transfer member 10. A voltage for transferring a toner image from the intermediate transfer body 10 to a transfer material is applied to the transfer roller 65 by a power supply 64.

The photosensitive drum 21 cleaned by the cleaning means 25 is uniformly charged by the charging means 22 and is exposed by the exposing means 23 to form an electrostatic latent image of a yellow image on the peripheral surface of the photosensitive drum 21. Is done. The electrostatic latent image of the yellow image is developed by the yellow developing unit 24Y. At this time, the magenta developing unit 24M, the cyan developing unit 24C, and the black developing unit 24K are in an inoperative state, and do not affect the development of the yellow toner image.
For the yellow toner image, the photosensitive drum 21 is
Is transferred to the intermediate transfer member 10 at a position where the intermediate transfer member 10 contacts the intermediate transfer member 10. This transfer is performed under a transfer electric field by the power supply 63. After the transfer, the photosensitive drum 21 is cleaned by the cleaning unit 25, charged again by the charging unit 22, and then subjected to exposure corresponding to the magenta image by the exposing unit 23, thereby forming an electrostatic latent image corresponding to the magenta image. Is formed on the peripheral surface of the photosensitive drum 21. Subsequently, a magenta toner image is formed by the magenta developing unit 24M, and is transferred onto the intermediate transfer body 10.

With the third and fourth rotations of the photosensitive drum 21, the cyan toner image and the black toner image are transferred to the intermediate transfer member 10.
It is transferred and formed on. These toner images are superimposed on the intermediate transfer member 10 to form a color toner image. When the color toner image reaches the position of the transfer roller 65, a transfer voltage is applied to the transfer roller 65 by the power supply 64. Further, the color toner image is transferred to the transfer roller 65.
The transfer material P is supplied at the timing when the transfer material P is reached. The transfer voltage from the power supply 64 is applied to the transfer material P via the transfer roller 65, and the color toner is transferred to the transfer material P.
Is transferred to The color toner image transferred to the transfer material P is fixed by the fixing unit 40.

FIG. 3 is a sectional view showing the structure of another color image forming apparatus (copier or laser beam printer) according to the present invention. The belt-shaped intermediate transfer body 10 uses an elastic body having a medium resistance.

Reference numeral 21 denotes a rotating drum type photosensitive drum repeatedly used as an electrophotographic photosensitive member, and is driven to rotate at a predetermined peripheral speed in a counterclockwise direction indicated by an arrow.

In the course of rotation, the photosensitive drum 21 is uniformly charged to a predetermined polarity and potential by the charging means 22, and then, in response to a time-series electric digital pixel signal of image information by an image exposure means (not shown). An electrostatic latent image corresponding to a yellow (Y) color component image of a target color image is formed by receiving image exposure using scanning exposure light or the like by the modulated laser beam.

Next, the electrostatic latent image is developed by the yellow (Y) developing means (yellow developing device) 24Y with the first color yellow toner. At this time the second to fourth
(Magenta color developing device, Cyan developing device, Black developing device) The developing devices 24M, 24C, and 24K are off and do not act on the photosensitive drum 21, and the first color yellow The toner image is not affected by the second to fourth developing means.

The intermediate transfer member 10 is rotated clockwise at the same peripheral speed as the photosensitive drum 21.

In the process in which the yellow toner image of the first color formed and carried on the photosensitive drum 21 passes through the nip portion between the photosensitive drum 21 and the intermediate transfer member 10, the primary transfer roller transfers the yellow toner image to the intermediate transfer member. An intermediate transfer (primary transfer) is sequentially performed on the outer peripheral surface of the intermediate transfer body 10 by an electric field formed by a primary transfer bias applied to the intermediate transfer body 10.

The surface of the photosensitive drum 1 after the transfer of the first color yellow toner image corresponding to the intermediate transfer member 10 is cleaned by the cleaning device 25.

Thereafter, similarly, the magenta toner image of the second color, the cyan toner image of the third color, and the black (black) toner image of the fourth color are sequentially superimposed on the intermediate transfer member 10 and transferred. A superimposed color toner image corresponding to the image is formed.

The secondary transfer roller 65 is provided on the lower surface of the intermediate transfer member 10 so as to be separated from the lower surface of the intermediate transfer member 10 so as to correspond to the secondary transfer opposing roller 34 and be supported in parallel.

The primary transfer bias for the sequential superposition transfer of the toner images of the first to fourth colors from the photosensitive drum 21 to the intermediate transfer member 10 has a polarity opposite to that of the toner and is applied from a bias power supply. The applied voltage is, for example, +100 V to +2
kV range.

In the primary transfer step of the first to third color toner images from the photosensitive drum 21 to the intermediate transfer member 10, the secondary transfer roller 65 and the intermediate transfer member cleaning means 16 are separated from the intermediate transfer member 10. Is also possible.

The transfer of the superimposed color toner image transferred onto the belt-shaped intermediate transfer member 10 onto the transfer material P, which is the second image carrier, is performed by the secondary transfer roller 65 using the intermediate transfer member 1.
At a predetermined timing at a predetermined timing at a contact nip between the belt of the intermediate transfer body 10 and the secondary transfer roller 65 through a paper feed roller (not shown) and a timing roller 18. P is fed. A secondary transfer bias is applied to the secondary transfer roller 65 from a bias power supply. With this secondary transfer bias, the superimposed color toner image is transferred (secondary transfer) from the intermediate transfer member 10 to the transfer material P as the second image carrier. The transfer material P to which the toner image has been transferred is introduced into the fixing unit 40 and is fixed by heating.

The color electrophotographic image forming apparatus using the above-mentioned intermediate transfer member is a conventional color electrophotographic image forming apparatus having an image forming apparatus for transferring an image from a photosensitive drum onto a transfer material while adhering the transfer material to the transfer material. In comparison with an electrophotographic apparatus, for example, a transfer apparatus as described in JP-A-63-301960, any processing and control (for example, gripping by a gripper, suction The image can be transferred from the intermediate transfer member without requiring a curvature, etc.), so that thin paper (40 g / m ² paper) such as envelopes, postcards and label paper can be transferred from thick paper (2 g).
(00 g / m ² paper), the second image bearing member has an advantage that it can be variously selected irrespective of its width, length, or thickness.

FIG. 4 is a sectional view showing the structure of another color image forming apparatus according to the present invention. FIG. 4 shows an example using a photosensitive drum of a transparent plastic cylindrical support. The transparent plastic cylindrical support of the photoreceptor drum 21 is manufactured by a centrifugal polymerization method or the like using methacrylic acid methyl ester monomer or the like. On this transparent support, a transparent conductive layer, ie, indium tin oxide (ITO), tin oxide, lead oxide, indium oxide, alumina, copper iodide, Au, A
A conductive resin is formed by mixing a resin and a conductive fine particle made of g, Ni, Al, or the like, and the photosensitive layer of the present invention is formed thereon.

Reference numeral 22 denotes a scorotron charger (hereinafter also simply referred to as charging means), which performs a charging action on the above-mentioned organic photoreceptor layer of the photoreceptor drum 21 by a grid maintained at a predetermined potential and corona discharge by a discharge wire. A uniform potential is applied to the photosensitive drum 21.

Reference numeral 23 denotes an image exposure means, that is, an exposure means composed of LEDs arranged in the axial direction of the photosensitive drum 21 and a selfoc lens which is a unit-magnification imaging system, which is read by a separate image reading device. Image signals of the respective colors are sequentially taken out of the memory and input to the respective exposure means 23 as electric signals.

Each of the exposure means 23 is attached to a support member 20 provided as an optical system support means, and is accommodated in the base of the photosensitive drum 21.

24Y to 24K are developing means for accommodating yellow (Y), magenta (M), cyan (C) and black (K) developers, each having a predetermined gap with respect to the peripheral surface of the photosensitive drum 21. And a developing sleeve 13 that rotates in the same direction while maintaining the image quality.

Each of the developing means is provided with the charging means 2 described above.
2. The electrostatic latent image on the photosensitive drum 21 formed by the charging by the exposure unit 2 and the image exposure by the exposure unit 23 is reversely developed in a non-contact state by applying a developing bias voltage.

The original image is stored in an image reading device separate from the present device, and the image read by the image pickup device or the image edited by the computer is temporarily stored in the memory as image signals for each of Y, M, C and K colors. And stored.

At the start of image recording, the photosensitive drum 21 is rotated in the counterclockwise direction by the start of the photosensitive member drive motor, and at the same time, the application of a potential to the photosensitive drum 21 is started by the charging action of the charging means 22Y.

After the photosensitive drum 21 is supplied with a potential, the exposure means 23Y starts exposure with an electric signal corresponding to a first color signal, that is, an image signal of yellow (Y), and the photosensitive drum 21 is rotated and scanned by the rotation of the drum. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer on the surface.

The latent image is reversal-developed by the developing means 24Y in a state in which the developer on the developing sleeve is not contacted, and a yellow (Y) toner image is formed in accordance with the rotation of the photosensitive drum 21.

Next, the photosensitive drum 21 is further provided with a potential on the yellow (Y) toner image by the charging action of the charging means 22M, and the second color signal of the exposure means 23M, that is, the image signal of magenta (M). The magenta (M) toner image is sequentially superimposed on the yellow (Y) toner image by non-contact reversal development by the developing unit 24M.

By the same process, a cyan (C) toner image corresponding to the third color signal is further produced by the charging means 22C, the exposing means 23C and the developing means 24C, and the cyan image is also produced by the charging means 22K, the exposing means 23K and the developing means 24K. A black (K) toner image corresponding to the fourth color signal is sequentially superposed, and a color toner image is formed on the peripheral surface within one rotation of the photosensitive drum 21.

The photosensitive drum 21 by each of these exposure means
Exposure to the organic photosensitive layer is performed from the inside of the drum through a substrate transparent to the above-mentioned exposure wavelength. Therefore, the exposure of the images corresponding to the second, third, and fourth color signals is performed without any influence from the previously formed toner image, and is equivalent to the image corresponding to the first color signal. It is possible to form an electrostatic latent image. In order to stabilize the temperature in the photosensitive drum 21 and prevent the temperature from rising due to the heat generated by each of the exposure means 23, a material having good thermal conductivity is used for the support member 20. In this case, measures such as radiating heat to the outside through the heat pipe can be suppressed to a level that does not cause any trouble. In the developing operation of each developing unit, a developing bias to which a direct current or a further alternating current is applied is applied to the developing sleeve 13, and a jumping development is performed by a one-component or two-component developer contained in the developing unit, and the developing sleeve 13 is transparent. Non-contact reversal development is performed on the photosensitive drum 21 that grounds the conductive layer.

Thus, the color toner image formed on the peripheral surface of the photosensitive drum 21 is temporarily transferred to the peripheral surface of the belt-shaped intermediate transfer body 10 provided as an intermediate transfer means.

The belt-like intermediate transfer member 10 has a thickness of 0.5 to
A 2.0 mm endless rubber belt having a semiconductive substrate of silicon rubber or urethane rubber having a resistance of 10 ⁸ to 10 ¹² Ω · cm, and a thickness of 5 μm on the outside of the rubber substrate as a toner filming prevention layer. It has a two-layer structure with a fluorine coating of ５０50 μm. This layer also preferably has a similar semiconductivity. 0.1-thick instead of rubber belt base
0.5mm semiconductive polyester or polystyrene,
Polyethylene, polyethylene terephthalate and the like can also be used. The belt-like intermediate transfer body 10 is a roller 34
A, 34B, 34C, and 34D are stretched and transported in a clockwise direction in synchronization with the peripheral speed of the photosensitive drum 21 by the power transmitted to the roller 34D.

The belt-like intermediate transfer member 10 is
The belt surface between the roller 4A and the roller 34B is
, And the belt surface on the outer periphery of the roller 34C is in contact with the transfer roller 65 as a transfer member, and a transfer area of the toner image is formed at each contact point.

The color toner image adhered to the peripheral surface of the photosensitive drum 21 is first transferred to the belt-shaped intermediate transfer member 1 described above.
By applying a bias voltage having a polarity opposite to that of the toner to the roller 34B at a contact point between 0 and 0, the toner image is sequentially transferred to the peripheral surface of the belt-shaped intermediate transfer body 10. That is, the color toner image on the drum is conveyed to the transfer area without scattering the toner by the guidance of the grounded roller 34A, and is efficiently transferred to the belt-shaped intermediate transfer body 10 by applying a bias voltage of 1 to 2 kV to the roller 34B. Is done.

On the other hand, the transfer paper P is carried out by the operation of the paper feed roller 17 of the paper feed cassette (not shown) and is fed to the timing roller 18 for transporting the color toner image on the belt-shaped intermediate transfer body 10. The paper is fed to the transfer area of the transfer roller 65 in synchronization.

The transfer roller 65 is rotated counterclockwise in synchronization with the peripheral speed of the belt-shaped intermediate transfer member 10.
The fed transfer paper P is brought into close contact with the color toner image on the belt-shaped intermediate transfer body 10 in a transfer area formed by a nip portion between the transfer roller 65 and the roller 34C which is in the ground state, and is transferred to the transfer roller 65. The application of the bias voltage of the opposite polarity to the toner of 1 to 2 kV sequentially transfers the color toner images onto the transfer paper P.

The transfer paper P having received the transfer of the color toner image is neutralized, conveyed to the fixing means 40 via the conveyance plate 19, and is heated by being pinched and conveyed between the heat roller 40A and the pressure roller 40B. After the toner is fused and fixed, the toner is discharged to the outside of the apparatus via a paper discharge roller 41.

The photosensitive drum 21 and the belt-shaped intermediate transfer member 10 have cleaning devices 25 and 1 respectively.
6 are provided, and the blades provided are constantly pressed against each other, and the remaining adhered toner is removed, so that the peripheral surface is always kept in a clean state.

[0252]

Next, embodiments of the present invention will be described specifically.
The configuration of the present invention is not limited to this.

A photoreceptor was prepared as follows (two photoreceptors for each example were prepared, one for photoreceptor for film thickness wear test and one for image evaluation).

Preparation of Photoreceptor 1 The following intermediate layer coating solution was prepared and applied on a cleaned cylindrical aluminum substrate by dip coating to form an intermediate layer having a dry film thickness of 0.3 μm.

<Intermediate Layer (UCL) Coating Solution> Polyamide resin (Amilan CM-8000: manufactured by Toray Industries, Ltd.) 60 g Methanol 1600 ml The following coating solutions were mixed and dispersed using a sand mill for 10 hours to prepare a charge generating layer coating solution. did. This coating solution was applied by a dip coating method to form a charge generation layer having a thickness of 0.2 μm.

<Charge Generating Layer (CGL) Coating Solution> Y-type titanyl phthalocyanine (the maximum peak angle of X-ray diffraction by Cu-Kα characteristic X-ray is 27.3 at 2θ) 60 g Silicone resin solution (KR5240, 15% xylene- Butanol solution: Shin-Etsu Chemical Co., Ltd.) 700 g 2-butanone 2000 ml The following coating solutions were mixed and dissolved to prepare a charge transport layer coating solution. This coating solution was applied on the charge generation layer by a dip coating method to form a charge transport layer having a thickness of 20 μm.

<Charge Transport Layer (CTL) Coating Solution> Charge transport substance (4-methoxy-4 '-(4-methyl-α-phenylstyryl) triphenylamine) 200 g Bisphenol Z-type polycarbonate (Iupilon Z300: Mitsubishi Gas Chemical) 300 g 1,2-dichloroethane 2000 ml The following coating solutions were mixed and dissolved to prepare a protective layer coating composition.

<Surface Layer (OCL) Coating Solution> Molecular sieve 4A was added to 10 parts by mass of a polysiloxane resin composed of 80 mol% of methylsiloxane units and 20 mol% of methyl-phenylsiloxane units, and left to stand for 15 hours for dehydration treatment did. This resin was dissolved in 10 parts by mass of toluene, and 5 parts by mass of methyltrimethoxysilane and 0.2 parts by mass of dibutyltin acetate were added thereto to form a uniform solution. The dihydroxymethyltriphenylamine (Exemplified Compound T-
1) 6 parts by mass were added and mixed, and this solution was dried to a thickness of 2 μm.
m, and cured by heating at 120 ° C. for 1 hour to prepare a photoreceptor 1.

Preparation of Photoreceptor 2 Photoreceptor 2 was prepared in exactly the same manner as in Preparation of Photoreceptor 1, except that 0.3 parts by mass of hindered amine (Exemplified Compound 2-1) was added to the surface layer.

Preparation of Photoreceptor 3 Photoreceptor 1 was prepared in exactly the same manner as in photoreceptor 1, except that dihydroxymethyltriphenylamine in the surface layer was replaced with 4- [2- (triethoxysilyl) ethyl] triphenylamine. Body 3 was produced.

Preparation of Photoreceptor 4 Photoreceptor 4 was prepared in exactly the same manner as in Preparation of Photoreceptor 2, except that the hindered amine in the surface layer was replaced with hindered phenol (Exemplified Compound 1-3).

Preparation of Photoconductor 5 Photoconductor 5 was prepared in the same manner as in preparation of photoconductor 1, except that the following intermediate layer was used.

<Intermediate layer (UCL) coating liquid> Zirconium chelate compound ZC-540 (Matsumoto Pharmaceutical Co., Ltd.) 200 g Silane coupling agent KBM-903 (Shin-Etsu Chemical Co., Ltd.) 100 g Methanol 700 ml Ethanol 300 ml Dip the above coating liquid Apply, dry at 150 ° C for 30 minutes,
An intermediate layer having a dry film thickness of 1.0 μm was formed.

Preparation of Photoreceptor 6 The following dispersion was prepared and applied on a cylindrical aluminum substrate obtained by drawing to form a conductive layer having a dry film thickness of 15 μm.

<Coating Solution for Conductive Layer (PCL)> Phenol resin 160 g Conductive titanium oxide 200 g Methyl cellosolve 100 ml The following intermediate layer coating solution was prepared. This coating solution was applied on the conductive layer by a dip coating method to form an intermediate layer having a dry film thickness of 1.0 μm.

<Intermediate Layer (UCL) Coating Solution> Polyamide resin (Amilan CM-8000: manufactured by Toray Industries, Ltd.) 60 g Methanol 1600 ml 1-butanol 400 ml The following coating solutions were mixed and dispersed using a sand mill for 10 hours. A coating solution was prepared. This coating solution was applied onto the intermediate layer by a dip coating method to form a charge generation layer having a dry film thickness of 0.2 μm.

<Charge Generating Layer (CGL) Coating Solution> Y-type titanyl phthalocyanine 60 g Silicone resin solution (KR5240, 15% xylene-butanol solution: Shin-Etsu Chemical Co., Ltd.) 700 g 2-butanone 2000 ml The following coating solutions were mixed and dissolved. Thus, a charge transport layer coating solution was prepared. This coating solution was applied on the charge generation layer by a dip coating method to form a charge transport layer having a thickness of 20 μm.

<Charge Transport Layer (CTL) Coating Solution> Charge transport substance (4-methoxy-4 '-(4-methyl-α-phenylstyryl) triphenylamine) 200 g Bisphenol Z-type polycarbonate (Iupilon Z300: Mitsubishi Gas Chemical) 300 g 1,2-dichloroethane 2000 ml <Coating solution for surface layer (OCL)> 10 parts by mass of a polysiloxane resin consisting of 80 mol% of methylsiloxane units and 20 mol% of methyl-phenylsiloxane units on the above CTL and molecular sieve 4A Was added and left to stand for 15 hours for dehydration treatment. This resin was dissolved in 10 parts by mass of toluene, and 5 parts by mass of methyltrimethoxysilane and 0.2 parts by mass of dibutyltin acetate were added thereto to form a uniform solution. In addition, dihydroxymethyltriphenylamine (Exemplified Compound T)
-1) 6 parts by mass were added and mixed.
It was applied as a surface layer having a thickness of μm, and was heated and cured at 120 ° C. for 1 hour to prepare a photoreceptor 6.

Preparation of Photoreceptor 7 In the preparation of Photoreceptor 6, dihydroxymethyltriphenylamine in the surface layer was replaced with 4- [2- (triethoxysilyl) ethyl] triphenylamine, and a hindered amine (Exemplified Compound 2- 1) Photoconductor 7 was prepared in exactly the same manner except that 0.3 parts by mass was added.

Preparation of Photoreceptor 8 Photoreceptor 8 was prepared in exactly the same manner as in preparation of photoreceptor 7, except that the hindered amine in the surface layer was changed to hindered phenol (Exemplified Compound 1-3).

Preparation of Photoreceptor 9 In the preparation of Photoreceptor 1, on the photoreceptor coated to CTL, a polysiloxane containing 1% by mass of silanol groups formed from 80 mol% of methylsiloxane units and 20 mol% of dimethylsiloxane units was formed. 10 parts by mass of a methylsiloxane resin was dissolved in 10 parts by mass of toluene, and molecular sieve 4A was added thereto. 5 parts by mass of methyltrimethoxysilane and 0.1 part of dibutyltin acetate were added thereto.
2 parts by mass were added to make a uniform solution. To 100 parts by mass of this composition, 200 parts by mass of toluene, 40 parts by mass of 4- [N, N-bis (3,4-dimethylphenyl) amino]-[2- (triethoxysilyl) ethyl] benzene and hindered amine (exemplary compound) 2-7) 0.3 part by mass was added and mixed, and this solution was applied as a surface layer having a dry film thickness of 2 μm, and was heated and cured at 140 ° C. for 4 hours to produce a photoreceptor 9.

Preparation of Photoreceptor 10 In the preparation of photoreceptor 6, on the photoreceptor coated up to CTL, a polysiloxane containing 1% by mass of silanol groups formed from 80% by mole of methylsiloxane unit and 20% by mole of dimethylsiloxane unit was prepared. 10 parts by mass of a methylsiloxane resin was dissolved in 10 parts by mass of toluene, and molecular sieve 4A was added thereto. 5 parts by mass of methyltrimethoxysilane and 0.1 part of dibutyltin acetate were added thereto.
2 parts by mass were added to make a uniform solution. To 100 parts by mass of this composition, 200 parts by mass of toluene, 40 parts by mass of 4- [N, N-bis (3,4-dimethylphenyl) amino]-[2- (triethoxysilyl) ethyl] benzene and hindered amine (exemplary compound) 2-7) 0.3 parts by mass were added and mixed, and this solution was applied as a surface layer having a dry film thickness of 2 μm, and was cured by heating at 140 ° C. for 4 hours.
Was prepared.

Preparation of Photoconductor 11 Photoconductor 11 was prepared in exactly the same manner as photoconductor 6, except that the conductive layer was replaced with the following composition.

<Conductive Layer (PCL) Composition> Phenol resin 160 g Conductive barium sulfate 200 g Methyl cellosolve 100 ml Silicone resin particles (average particle size 2 μm) 3 g Preparation of photoreceptor 12 In the preparation of photoreceptor 1, a cylindrical aluminum substrate was used. A photoreceptor 12 was prepared in exactly the same manner except that the sealed aluminum alumite cylindrical aluminum substrate was used.

Preparation of Photoreceptor 13 In the preparation of Photoreceptor 1, the cylindrical aluminum substrate was replaced with a sealed alumite cylindrical aluminum substrate.
The polysiloxane resin of the surface layer coating solution was prepared by adding 30 mol% of a methylsiloxane unit, 40 mol% of an ethylsiloxane unit,
A photoreceptor 13 was prepared in exactly the same manner except that a polysiloxane resin (containing 2% by mass of silanol groups) composed of 20 mol% of dimethylsiloxane units and 10 mol% of diethylsiloxane units was used.

Preparation of Photoreceptor 14 In the preparation of Photoreceptor 1, a polysiloxane resin was prepared by mixing 30 mol% of methylsiloxane units, 30 mol% of phenylsiloxane units, 20 mol% of dimethylsiloxane units, and 20 mol% of diethylsiloxane units. A photoreceptor 14 was prepared in exactly the same manner except that the siloxane resin (containing 2% by mass of a silanol group) was used.

Preparation of Photoconductor 15 Photoconductor 1 was prepared in exactly the same manner as photoconductor 1 except that dihydroxymethyltriphenylamine (exemplified compound T-1) was replaced with hydrazone-type exemplified compound H-1.
5 was produced.

Preparation of Photoconductor 16 Photoconductor 1 was prepared in exactly the same manner as photoconductor 1 except that dihydroxymethyltriphenylamine (exemplified compound T-1) was replaced with stilbene-type exemplified compound S-1.
No. 6 was produced.

Preparation of Photoreceptor 17 Photoreceptor 17 was prepared in exactly the same manner as in photoreceptor 1 except that dihydroxymethyltriphenylamine (exemplified compound T-1) was replaced by benzidine-type exemplified compound Be-1. Produced.

Preparation of Photoreceptor 18 Photoreceptor 18 was prepared in exactly the same manner as in photoreceptor 1 except that dihydroxymethyltriphenylamine (exemplified compound T-1) was replaced with butadiene-type exemplified compound Bu-1. Produced.

Preparation of Photoconductor 19 In the preparation of Photoconductor 1, dihydroxymethyltriphenylamine (Exemplified Compound T-1) was replaced with Exemplified Compound So-
A photoconductor 19 was prepared in exactly the same manner except that the photoconductor 19 was changed to 1.

Preparation of Photoconductor 20 In the preparation of Photoconductor 1, dihydroxymethyltriphenylamine (Exemplified Compound T-1) was replaced with Exemplified Compound V-1.
The photoreceptor 20 was produced in exactly the same manner except that

Preparation of Photoconductor 21 In the preparation of Photoconductor 1, dihydroxymethyltriphenylamine (Exemplified Compound T-1) was replaced with Exemplified Compound W-1.
The photoreceptor 21 was produced in exactly the same manner except that

Preparation of Photoreceptor 22 Except for changing the coating solution for the intermediate layer to the coating solution for the intermediate layer of Photoreceptor 5 and adding 5 parts by mass of colloidal silica to the coating solution for the surface layer in the preparation of the photoreceptor 1, And the photoreceptor 22
Was prepared.

Preparation of Photoreceptor 23 Photoreceptor 23 was prepared in exactly the same manner as in Preparation of Photoreceptor 1, except that 12 parts by mass of colloidal silica was added to the surface layer.

Preparation of Photoreceptor 24 In the preparation of Photoreceptor 1, CTL was prepared. Then, 60 parts by mass of a commercially available curable siloxane resin KP-854 (manufactured by Shin-Etsu Chemical Co., Ltd.) and 60 parts by mass of isopropanol were added and uniformly dissolved, and dihydroxymethyltriphenylamine (Exemplified Compound T-1) was added thereto. 6) Parts by mass were added and mixed, and this solution was applied so as to form a surface layer having a dry film thickness of 1 μm, and dried at 120 ° C. for 1 hour to obtain a photosensitive member 24.
Was prepared.

Production of Photoconductor 25 In the production of photoconductor 24, siloxane resin KP-85 was used.
X-40-2239 (manufactured by Shin-Etsu Chemical Co., Ltd.) instead of 4
A photoreceptor 25 was prepared in exactly the same manner except that was used.

Preparation of Photoconductor 26 In the preparation of photoconductor 24, siloxane resin KP-85 was used.
X-40-2269 (Shin-Etsu Chemical Co., Ltd.) instead of 4
A photoreceptor 26 was prepared in exactly the same manner except that

Preparation of Photoreceptor 27 In the preparation of Photoreceptor 2, the hindered amine in the surface layer was mixed with an antioxidant (Exemplary Compound 1-1) and an antioxidant (Exemplary Compound 4-1) (mixing ratio: 1/1). The photoreceptor 27 was produced in exactly the same manner as in the above, except that the above was changed to ()).

Preparation of Photoreceptor 28 Photoreceptor 28 was prepared in exactly the same manner as in Preparation of Photoreceptor 1, except that 0.25 parts by mass of silicone resin particles having an average particle diameter of 1 μm were added to the surface layer.

Preparation of Photoreceptor 29 Photoreceptor 29 was prepared in exactly the same manner as in photoreceptor 28 except that the silicone resin particles in the surface layer were changed to silica particles having an average particle size of 0.5 μm and 3 parts by mass. did.

Preparation of Photoreceptor 30 In the preparation of Photoreceptor 1, coating was performed in the same manner up to the charge generation layer.

<Charge Transporting Layer CTL> Charge transporting substance (exemplified compound T-1) 200 g Methyltrimethoxysilane 300 g Hindered phenol compound (exemplified compound 1-4) 1 g Colloidal silica (30% methanol solution) 8 g 1-butanol 50 g 50 g of 1% acetic acid, 2 g of aluminum tetraacetyl acetate, and 10 g of fluororesin particles (average particle size: 1 μm) were mixed and dissolved to prepare a charge transport layer coating solution. This coating solution is applied on the charge generation layer by a dip coating method.
The resultant was cured by heating at 10 ° C. for 2 hours to form a charge transport layer having a dry film thickness of 12 μm.

Preparation of Photoreceptor 31 In the preparation of Photoreceptor 1, the charge transport layer was formed in the same manner. Further, the following compounds were mixed and dissolved thereon to prepare a surface layer coating solution.

<Surface Layer (OCL) Coating Solution> Charge Transport Material (Exemplified Compound T-1) 200 g Methyltrimethoxysilane 300 g Hindered Phenol Compound (Exemplified Compound 1-3) 1 g Colloidal Silica (30% methanol solution) 8 g Ethanol / T-butanol (1/1 mass ratio) 50 g 1% acetic acid 50 g aluminum tetraacetyl acetate 2 g silicone oil (KF-54) (Shin-Etsu Chemical Co., Ltd.) 1 g is mixed, dissolved and dried to form a surface layer having a dry film thickness of 2 μm. And cured by heating at 110 ° C. for 1 hour to produce a photoreceptor 31.

Preparation of Photoconductor 32 In preparation of photoconductor 31, methyltrimethoxysilane in the surface layer was changed to methyltrimethoxysilane and dimethyldimethoxysilane (6/4 mass ratio), and silicone oil KF-54 was replaced with X-. A photoconductor 32 was prepared in exactly the same manner except that the photoconductor 32 was replaced with 22-160AS.

Preparation of Photoreceptor 33 In the preparation of Photoreceptor 30, the hindered phenol compound in the charge transport layer was replaced with an antioxidant (Exemplified Compound 2-3), and the fluororesin particles were replaced with silica particles (average particle size 2 μm).
A photoreceptor 33 was produced in exactly the same manner except that

Preparation of Photoreceptor 34 In the preparation of Photoreceptor 1, commercially available primer PC-7J (manufactured by Shin-Etsu Chemical Co., Ltd.) was diluted twice with CTL on toluene, coated, dried at 100 ° C. for 30 minutes, and dried. Film thickness 0.
An adhesive layer of 3 μm was formed. Further, 10 parts by mass of a polysiloxane resin (containing 1% by mass of silanol groups) composed of 80% by mol of methylsiloxane units and 20% by mol of methyl-phenylsiloxane units was further added with molecular sieve 4
A was added, and the mixture was allowed to stand for 15 hours to perform a dehydration treatment. This resin was dissolved in 10 parts by mass of toluene, and 5 parts by mass of methyltrimethoxysilane and 0.2 parts by mass of dibutyltin acetate were added thereto to form a uniform solution. To this, 6 parts by mass of dihydroxymethyltriphenylamine (Exemplified Compound T-1) was added and mixed. The solution was applied as a surface layer having a dry film thickness of 1 μm, and dried at 120 ° C. for 1 hour to obtain a photosensitive member 34. Was prepared.

Preparation of Photoreceptor 35 Photoreceptor 35 was prepared in the same manner as in preparation of Photoreceptor 1, except that 6 parts by mass of dihydroxymethyltriphenylamine (Exemplified Compound T-1) was removed from OCL.

Preparation of Photoreceptor 36 Photoreceptor 36 was prepared in exactly the same manner as in photoreceptor 1 except that OCL was omitted.

The photoreceptors 1 to 36 were subjected to a film thickness reduction test for 1,000,000 revolutions of each photoreceptor, and the thickness loss per rotation was determined from the results. Table 1 shows the results.

[0302]

[Table 1]

Next, an image evaluation toner of the present invention was prepared as follows. * Preparation of Toner 1-K, Toner 1-Y, Toner 1-M, Toner 1-C 100 parts of styrene-acryl resin having a mass ratio of styrene: butyl acrylate: butyl methacrylate = 75: 20: 5, carbon black 10 And 4 parts of low molecular weight polypropylene (number average molecular weight = 3500)
After kneading, the mixture was finely pulverized using a mechanical pulverizer and classified by an air classifier to obtain colored particles having a volume average particle size of 5.2 μm. Hydrophobic silica (degree of hydrophobicity = 75 / number average primary particle diameter = 12 nm) was added to the colored particles by 1.2.
%, And 1.2% by mass of 0.05 μm titanium oxide, and stirred at 53 ° C. to obtain a toner. This is referred to as “Toner 1
−K ”.

In the production of Toner 1-K, C.I. I. Pigment Yellow 1
"Toner 1-Y" was obtained in the same manner except that eight parts of 85 were used.

In the production of Toner 1-K, C.I. I. Pigment Red 12
"Toner 1-M" was obtained in the same manner except that 10 parts of No. 2 were used.

In the production of Toner 1-K, C.I. I. Pigment Blue 1
"Toner 1-C" in the same manner except that 5 parts of 5: 3 were used.
I got

* Toner 2-K, Toner 2-Y, Toner 2
-M, Preparation of Toner 2-C 100 parts of styrene-acryl resin having a mass ratio of styrene: butyl acrylate: butyl methacrylate: acrylic acid = 75: 18: 5: 2, carbon black 1
0 parts, low molecular weight polypropylene (number average molecular weight = 350
0) 4 parts were melted and kneaded, and then finely pulverized by a pneumatic classifier using a mechanical pulverizer, and classified to obtain colored particles having a volume average particle diameter of 6.2 μm. 1.2% by mass of hydrophobic silica (hydrophobicity = 75 / number average primary particle size = 12 nm) and 0.8% by mass of melamine formaldehyde resin particles of 0.2 μm are added to the colored particles to form a toner. Obtained. This is referred to as “toner 2-K”.

In the production of Toner 2-K, C.I. I. Pigment Yellow 1
"Toner 2-Y" was obtained in the same manner except that 8 parts of 85 were used.

In the production of Toner 2-K, C.I. I. Pigment Red 12
"Toner 2-M" was obtained in the same manner except that 10 parts of No. 2 were used.

In the production of Toner 2-K, C.I. I. Pigment Blue 1
"Toner 2-C" in the same manner except that 5 parts of 5: 3 were used.
I got

* Toner 3-K, Toner 3-Y, Toner 3
-M, Preparation of Toner 3-C Styrene: butyl acrylate: methacrylic acid = 70:
Styrene-acrylic resin 1 having a mass ratio of 20:10
After melting and kneading 00 parts, 10 parts of carbon black, and 4 parts of low molecular weight polypropylene (number average molecular weight = 3500), pulverize using a mechanical pulverizer, classify with an air classifier, and volume average. Colored particles having a particle size of 5.3 μm were obtained. 1.0% by mass of hydrophobic silica (hydrophobicity = 75 / number average primary particle size = 13 nm) and 0.6% by mass of 0.5 μm titanium oxide are added to the colored particles, and the mixture is heated at 51 ° C. After stirring, a toner was obtained. This is referred to as “Toner 3
−K ”.

In the production of Toner 3-K, C.I. I. Pigment Yellow 1
"Toner 3-Y" was obtained in the same manner except that 8 parts of 85 were used.

In the production of Toner 3-K, C.I. I. Pigment Red 12
"Toner 3-M" was obtained in the same manner except that 10 parts of No. 2 were used.

In the production of Toner 3-K, C.I. I. Pigment Blue 1
"Toner 3-C" was prepared in the same manner except that 5 parts of 5: 3 were used.
I got

* Toner 4-K, Toner 4-Y, Toner 4
-M, Preparation of Toner 4-C Sodium n-dodecyl sulfate = 0.90 kg and pure water 1
Add 0.0L and dissolve with stirring. To this solution, with stirring, Regal 330R (carbon black manufactured by Cabot Corporation)
20 kg was gradually added, and then the mixture was continuously dispersed for 20 hours using a sand grinder (medium type disperser). After dispersion, ELS-8 electrophoretic light scattering photometer manufactured by Otsuka Electronics Co., Ltd.
As a result of measuring the particle size of the dispersion liquid using No. 00, the weight average particle size was 122 nm. The solid content concentration of the dispersion was 16.6% by mass as measured by a mass method based on standing drying. This dispersion is referred to as “colorant dispersion 1”.

[0316] 0.055 kg of sodium dodecylbenzenesulfonate is mixed with 4.0 L of ion-exchanged water and dissolved by stirring at room temperature. This is designated as an anionic surfactant solution A.

Nonylphenyl alkyl ether 0.01
4 kg is mixed with 4.0 L of ion-exchanged water and dissolved by stirring at room temperature. This is designated as nonionic surfactant solution A.

223.8 g of potassium persulfate is mixed with 12.0 L of ion-exchanged water and dissolved by stirring at room temperature. This is called initiator solution A.

A 100 L reactor equipped with a temperature sensor, a cooling pipe, and a nitrogen introducing device was charged with a number average molecular weight (Mn) of 35.
Then, 3.41 kg of the polypropylene emulsion of No. 00, anionic surfactant solution A and nonionic surfactant solution A are added, and stirring is started. Then, ion-exchanged water 44.0
Add L.

Heating is started, and when the liquid temperature reaches 75 ° C., the entire amount of the initiator solution A is added. Then, while controlling the liquid temperature to 75 ° C. ± 1 ° C., 12.1 kg of styrene
And 2.88 kg of n-butyl acrylate, 1.04 kg of methacrylic acid and 548 g of t-dodecylmercaptan.

Further, the liquid temperature was raised to 80 ° C. ± 1 ° C.
Heating and stirring were performed for 6 hours. The liquid temperature is cooled to 40 ° C. or less, and the stirring is stopped. The mixture was filtered with a pole filter to obtain latex A1.

The glass transition temperature of the resin particles in the latex A1 was 57 ° C., the softening point was 121 ° C., and the molecular weight distribution was as follows.
It was 0 nm.

A mixture of potassium persulfate (200.7 g) and ion-exchanged water (12.0 L) is dissolved under stirring at room temperature. This is designated as initiator solution B.

A nonionic surfactant solution A is charged into a 100 L reaction vessel equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a comb baffle, and stirring is started. Next, 44.0 L of ion-exchanged water is charged.

The heating is started, and when the liquid temperature reaches 70 ° C., the initiator solution B is added. At this time, styrene 1
1.0 kg, 4.00 kg of n-butyl acrylate, 1.04 kg of methacrylic acid, and t-dodecyl mercaptan 9.
And a solution obtained by previously mixing 02 g with the mixture.

Thereafter, the liquid temperature was controlled at 72 ° C. ± 2 ° C., and the mixture was heated and stirred for 6 hours. Further, the liquid temperature is set to 80 ° C.
The temperature was raised to ± 2 ° C., and the mixture was heated and stirred for 12 hours.

The temperature of the solution is cooled to 40 ° C. or less, and the stirring is stopped. The solution was filtered through a pole filter, and the filtrate was used as latex B1.

The resin particles in the latex B1 have a glass transition temperature of 58 ° C., a softening point of 132 ° C., a molecular weight distribution of weight average molecular weight = 245,000, and a weight average particle size of 11
It was 0 nm.

Sodium chloride as salting-out agent = 5.36
kg and 20.0 L of ion-exchanged water are added and stirred and dissolved.
This is designated as sodium chloride solution A.

A 100-L SUS reaction vessel equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a comb-shaped baffle (the stirring blade was an anchor blade) was charged with the latex A1 = 2 prepared above.
0.0 kg, latex B1 = 5.2 kg, colorant dispersion 1 = 0.4 kg, and ion-exchanged water 20.0 kg are stirred. Then, the mixture is heated to 35 ° C., and sodium chloride solution A is added. Thereafter, after standing for 5 minutes, heating is started and the temperature is increased to 85 ° C. in 5 minutes (heating rate =
10 ° C / min). The mixture is heated and stirred at a liquid temperature of 85 ° C. ± 2 ° C. for 6 hours to cause salting out / fusion. Thereafter, the mixture is cooled to 30 ° C. or lower and the stirring is stopped. The solution is filtered through a sieve having an opening of 45 μm, and this filtrate is used as an association liquid. Then use a centrifuge,
Non-spherical particles in the form of a wet cake were collected by filtration from the associated liquid. Thereafter, the substrate was washed with ion-exchanged water.

The wet cake-like colored particles which had been washed as described above were dried with warm air at 40 ° C. to obtain colored particles.
The volume average particle size of the colored particles was 4.6 μm. Further, the colored particles are added to hydrophobic silica (hydrophobicity = 65,
1.0% by mass of a number average primary particle size = 12 nm) and 1.0% by mass of 0.1 μm styrene-methyl methacrylate particles, and the mixture was stirred at 46 ° C.
K "was obtained.

In the production of Toner 4-K, C.I. I. Pigment Yellow 1
"Toner 4-Y" was obtained in the same manner except that eight parts of 85 were used.

In the production of Toner 4-K, C.I. I. Pigment Red 12
"Toner 4-M" was obtained in the same manner except that 10 parts of No. 2 were used.

In the production of Toner 4-K, C.I. I. Pigment Blue 1
"Toner 4-C" in the same manner except that 5 parts of 5: 3 were used.
I got

* Toner 5-K, Toner 5-Y, Toner 5
-M, Preparation of Toner 5-C Coloring particles of which the particle size was changed by changing the fusing condition of the toner 4 were prepared, and hydrophobic silica (hydrophobicity =
65, a number average primary particle size = 12 nm) of 1.0 mass%, and 1.6 μm of titanium oxide 1.6 mass%, and 26
C. to obtain "Toner 5-K".

In the production of Toner 5-K, C.I. I. Pigment Yellow 1
"Toner 5-Y" was obtained in the same manner except that eight parts of 85 were used.

In the production of Toner 5-K, C.I. I. Pigment Red 12
"Toner 5-M" was obtained in the same manner except that 10 parts of No. 2 were used.

In the production of Toner 5-K, C.I. I. Pigment Blue 1
"Toner 5-C" in the same manner except that 5 parts of 5: 3 were used.
I got

The characteristics of each of the toners were evaluated, and the measurement results are shown in Table 2.

[0340]

[Table 2]

Method for measuring volume average particle diameter of toner: Measured by Coulter Multisizer. Measuring method of sum of relative frequency of number distribution of toner particles: Particle size data of each toner measured by a Coulter Multisizer is transferred to a computer via an I / O unit, and the computer calculates relative frequency m ₁ and m ₂ . Sum M
I asked.

Preparation of Developer The above toners, that is, toners 1-K to 5-C (20 toners in total), were mixed with a ferrite carrier coated with a silicone resin and having a volume average particle diameter of 45 μm. Each developer having a concentration of 6% was adjusted and used for evaluation. These 24 types of developers are referred to as developer 1-K to developer 5-C, respectively, corresponding to the toner.

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

<Evaluation> In each example and comparative example, Y of toner (developer) and photoreceptor (four photoreceptors having the same formulation in each example and comparative example) shown in Tables 3 and 4 were used. ,
It is mounted on a digital copying machine having the intermediate transfer member shown in FIG. 2 having M, C, and K image forming units, and a white background portion, a solid black portion, a solid image portion of red, green, and blue, a character image portion, An A4 image having the following formula (1) was imaged using neutral paper at room temperature and normal humidity (20 ° C., 50% RH) until the image formation by the photoreceptor reached 1,000,000 rotations. The evaluation was performed at the initial stage and on an image corresponding to the 1,000,000th rotation. The results are shown in Tables 3 and 4.

Process conditions of digital copying machine having intermediate transfer member Charging means: scorotron charger Image exposure means: semiconductor laser Developing means: two-component contact reversal development in which photoconductor and developer are contacted Cleaning conditions: for photoconductor A cleaning blade having a hardness of 70 °, a rebound resilience of 34%, a thickness of 2 (mm), and a free length of 7 mm was abutted against the counter direction by a weight load method so as to have a linear pressure of 20 (g / cm).

(1) Image evaluation The image density and fog were measured using a densitometer “RD-918” (manufactured by Macbeth) for the white background and solid black of the image at 1,000,000 rotations. The fog was measured at a relative density with the paper being zero. The presence or absence of image blur was visually evaluated.

A. Image density ・ ・ ・: 1.4 or more / Good ・ ・ ・: 1.0 or more to less than 1.4 / No problem in practical use ×: Less than 1.0 / Problem in practical use b. Fog ・ ・ ・: Less than 0.001 / Good ・ ・ ・: 0.001 or more to less than 0.003 / No practical problem x: 0.003 or more / Practical problem c. Image blurring (evaluation of image blurring in image of character part) ◎ ・ ・ ・ 5 or less out of 50,000 sheets / good ○ ・ ・ ・ 6 to 20 out of 50,000 sheets / No problem in practical use ×: 21 or more sheets out of 50,000 sheets / a problem in practical use d. Fine Line Reproducibility The line width of a line image corresponding to a 2-dot line image signal was measured by a print evaluation system “RT2000” (manufactured by Yarman Corporation).

A: Line width of first formed image (L
1) and the line width (L1
Is not more than 200 μm, and the change in line width (L1−L1,000,000) is not more than 10 μm / good.... In other cases / practical problem e. Color difference Secondary colors (red, blue, and yellow) of each of the Y, M, and C toners of the first formed image and the formed image at the 1,000,000th rotation.
Green) solid image part is "MacbethC
color-Eye7000 ", and CMC
The color difference was calculated using the (2: 1) color difference equation.

◎: color difference of 5 or less / good ×: color difference of more than 5 / practical problem f. Evaluation of black spots The evaluation of black spots was performed using the image analyzer "Omnicon 3000".
The shape and the number of black spots are measured using a “type” (manufactured by Shimadzu Corporation), the particle diameter and the number of black spots are measured, and the number of black spots of 0.1 mm or more is determined per 100 cm ^2. did.
Other large cuts and the like were visually judged. The criterion for black spot evaluation is as follows.

Black spot (formed image at 1 millionth rotation): 1 or less / A4 paper / good ○: 2 to 3 / A4 paper / Practical problem level × ..4 or more / one A4 sheet / practical problem g. Uneven wear amount (μm) Absolute value of the difference in film thickness at 3 cm from the center and the end of the photosensitive drum for black | Thickness of photosensitive member at 1,000,000th rotation-3 cm from end at 1,000,000th rotation The film thickness at the point | = Δd (μm) Photoreceptor film thickness measuring method The film thickness of the photosensitive layer is measured at random at 10 places of uniform film thickness, and the average value is defined as the film thickness of the photosensitive layer. The film thickness measuring device is an eddy current type film thickness measuring device EDDY560C (HELMUT
FISCHER GMBTE CO).

H. Image Registration With respect to the line width of a line image corresponding to an image signal of a two-dot line in which magenta and cyan are superimposed, the protruding length of each color was measured in an image at 1,000,000 rotations.

Less than 70 μm: 良好: good Good: less than 70 to 100 μm: ○: no problem in practical use 100 to less than 150 μm: Δ: severely impossible in practical use 150 μm or more: x: unsuitable

[0353]

[Table 3]

[0354]

[Table 4]

As is clear from Tables 3 and 4, in Examples 1 to 34 of the present invention, no fogging occurred even in the image at the 1,000,000th rotation, and the density of the solid black portion was 1 in reflection density. A concentration of 4 or more, without any misregistration,
An image with excellent color balance was obtained. Also, the amount of wear per rotation of each photoconductor at the end of one million sheets was 1.0 × 1.
0 was very low and ^-5 [mu] m or less. Further, no image defects such as black spots or blurred images occurred, and the resolution was good.

On the other hand, Comparative Examples 4 and 5 in which the surface layer of the photoreceptor is out of the range of the present invention, and Comparative Examples 1 to 3 in which the variation coefficient of the shape factor and the number variation coefficient of the toner exceeded the range of the present invention. Good images have not been obtained.

[0357]

According to the image forming apparatus of the intermediate transfer system of the present invention, a highly durable and finally obtained electrophotographic image is free from image defects such as misregistration. It is possible to provide a clear color image that does not cause image blur or the like.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a contact condition of a cleaning blade to a photoconductor in a wear test.

FIG. 2 is a sectional view illustrating a configuration of a color image forming apparatus according to the present invention.

FIG. 3 is a sectional view illustrating the configuration of another color image forming apparatus according to the present invention.

FIG. 4 is a sectional view illustrating a configuration of another color image forming apparatus of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 electrophotographic photosensitive member 2 cleaning blade 3 support member 4 fixing screw θ contact angle L free length a biting amount C central axis 10 intermediate transfer body (intermediate transfer means) 21, 21Y, 21M, 21C, 21K photosensitive drum (electronic Photosensitive body) 22, 22Y, 22M, 22C, 22K Charging means 23, 23Y, 23M, 23C, 23K Exposure means 24Y, 24M, 24C, 24K Developing means 25 Cleaning means P Transfer material (transfer paper)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 5/147 504 G03G 5/147 504 9/09 15/16 15/16 9/08 361

Claims (17)

[Claims] 1. A toner image formed on an electrophotographic photosensitive member is temporarily transferred onto an intermediate transfer member by a developing means provided around the electrophotographic photosensitive member. In an image forming apparatus for transferring an image to a transfer material and removing residual toner on the surface of the electrophotographic photoreceptor by a cleaning unit, the coefficient of variation of the shape coefficient of the toner used in the developing unit is 16% or less, and the number variation coefficient Is not more than 27%, and the film thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member in the following wear test is 0 ≦ Δ
An image forming apparatus, wherein Hd <1 × 10 ⁻⁵ .・ Wear test Under normal temperature and normal humidity (20 ° C., 50% RH), the electrophotographic photosensitive member connected to the drive unit has a hardness of 70 ± 1 ° and a rebound resilience of 35 ± 1.
%, A thickness of 2 ± 0.1 (mm), and a free blade of 9 ± 0.1 mm with a contact angle of 10 ± in the counter direction.
0.5 °, biting amount 1.5 ± 0.2 (mm) abuts on the electrophotographic photoreceptor while rotating the electrophotographic photoreceptor by a drive unit at a rotation of 0.1 to 10 seconds per rotation. 0.
A powder having a bulk density of 0.41 ± 0.1 g / cm ³ and a number average particle diameter of 10 to 40 (nm) developed with an adhesion amount of 15 ± 0.05 (mg / cm ² ) is an external additive. The toner having a volume average particle diameter of 8.5 ± 0.2 μm mixed at 1 ± 0.1 mass (%) with respect to the toner is cleaned. The film thickness variation of the electrophotographic photosensitive member when the electrophotographic photosensitive member was rotated 100,000 times or more under the above conditions was measured,
The value obtained by dividing the value by the number of rotations of the electrophotographic photoreceptor is defined as the thickness loss per rotation. 2. A plurality of developing means containing at least toners having different hues are provided around an electrophotographic photosensitive member, and the plurality of developing means are sequentially operated, so that each developing means is provided on the electrophotographic photosensitive member. A color toner image is formed by successively superimposing the toner images formed corresponding to the intermediate transfer member on the intermediate transfer member, and the color toner image on the intermediate transfer member is collectively transferred to a transfer material, and is transferred onto the intermediate transfer member. In the image forming apparatus in which the residual toner on the electrophotographic photosensitive member is removed by the cleaning unit after the transfer of the color toner, the variation coefficient of the shape factor of the toner used in the developing unit is 16% or less, and the number variation coefficient is 27. % or less, and an image forming, wherein the electrophotographic photosensitive member of the first film thickness depletion amount DerutaHd per revolution ([mu] m) is 0 ≦ ΔHd <1 × 10 ^-5 in the abrasion test Location. 3. An electrophotographic photosensitive member, wherein a plurality of sets of charging means, image exposing means and developing means are provided, and charging, image exposing and developing are repeated during one rotation of the electrophotographic photosensitive member. In a color image forming apparatus for forming a plurality of toner images on the peripheral surface of a photoreceptor by superimposing them, transferring the superimposed color toner images onto an intermediate transfer body at a time, and then transferring the image to a transfer material, The variation coefficient of the shape coefficient of the toner to be used is 16% or less, and the number variation coefficient is 27%.
And the film thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member in the wear test is 0 ≦
An image forming apparatus, wherein ΔHd <1 × 10 ⁻⁵ . 4. The electrophotographic photosensitive member according to claim 1, wherein the electrophotographic photosensitive member has at least a plurality of resin layers on a cylindrical conductive support. Image forming device. 5. One of the plurality of resin layers is a surface layer, and the surface layer has a structural unit having charge transport performance,
The image forming apparatus according to claim 4, further comprising a siloxane-based resin having a crosslinked structure. 6. It has a structural unit having the charge transporting performance.
And a siloxane-based resin having a cross-linked structure is a hydroxyl group,
Or an organosilicon compound having a hydrolyzable group, and
Obtained by reacting with the compound represented by the general formula (2)
6. The siloxane resin according to claim 5,
Image forming apparatus. General formula (2) B- (R₁-ZH)_m In the formula, B is a monovalent or monovalent compound containing a structural unit having charge transporting performance
Represents a polyvalent group; ₁Is a single bond or divalent alkylene
Z represents an oxygen atom, a sulfur atom or NH;
Represents an integer of 1 to 4. 7. The image forming apparatus according to claim 6, wherein Z in the general formula (2) is an oxygen atom. 8. The image forming apparatus according to claim 5, wherein the surface layer contains an antioxidant. 9. The image forming apparatus according to claim 8, wherein the antioxidant is a hindered phenol antioxidant or a hindered amine antioxidant. 10. The method according to claim 5, wherein the surface layer contains organic or inorganic particles.
Item 10. The image forming apparatus according to item 1. 11. The image forming apparatus according to claim 5, wherein said surface layer contains colloidal silica. 12. The toner according to claim 1, wherein the toner used in said developing means contains at least 65% by number of toner particles having a shape factor in the range of 1.0 to 1.6.
The image forming apparatus according to claim 1. 13. The toner according to claim 1, wherein the toner used in said developing means has a volume average particle size of 4 to 9 μm and 30% or less of toner particles having a volume average particle size of 3.0 μm or less.
13. The image forming apparatus according to claim 12. 14. When the particle size of the toner used in the developing means 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. The relative frequency (m ₁ ) of the toner particles included in the most frequent class and the relative frequency (m ₁ ) of the toner particles included in the next frequent class after the most frequent class
The image forming apparatus according to any one of claims 1 to 13, wherein the sum of relative frequencies (M) to ( ₂ ) is 70% or more. 15. A toner image formed on the electrophotographic photosensitive member is temporarily transferred onto an intermediate transfer member by a developing process provided around the electrophotographic photosensitive member, and then the toner image on the intermediate transfer member is transferred. In an image forming method in which an image is transferred to a transfer material and residual toner on the surface of the electrophotographic photoreceptor is removed by a cleaning step, the coefficient of variation of the shape factor of the toner used in the developing step is 16% or less, and the number variation coefficient Is 27%
And the film thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member in the wear test is 0 ≦
An image forming method, wherein ΔHd <1 × 10 ⁻⁵ . 16. A plurality of developing steps containing at least toners having different hues are provided around an electrophotographic photosensitive member,
By sequentially operating the plurality of developing steps, a toner image formed on the electrophotographic photosensitive member corresponding to each developing step is sequentially superimposed on an intermediate transfer member to form a color toner image. The image forming method of claim 1, wherein the color toner image on the intermediate transfer body is collectively transferred to a transfer material, and the residual toner on the electrophotographic photoreceptor is removed by a cleaning step after the transfer of the color toner on the intermediate transfer body. The variation coefficient of the shape factor of the toner used in the process is 16% or less;
And the number variation coefficient is 27% or less, and the film thickness loss amount ΔHd (μm) per rotation of the electrophotographic photosensitive member in the wear test is 0 ≦ ΔHd <1 × 10 ^−5. Image forming method. 17. An electrophotographic photoreceptor having a plurality of sets of a charging step, an image exposing step, and a developing step, wherein charging, image exposing, and developing are repeated during one rotation of the electrophotographic photoreceptor. A color image forming method in which a plurality of toner images are formed by superimposing on the peripheral surface of a photoreceptor, and the superimposed color toner images are collectively transferred onto an intermediate transfer body and then transferred to a transfer material, and are used in the developing step. The variation coefficient of the shape coefficient of the toner to be used is 16% or less, and the number variation coefficient is 27%.
And the film thickness loss ΔHd (μm) per rotation of the electrophotographic photosensitive member in the wear test is 0 ≦
An image forming method, wherein ΔHd <1 × 10 ⁻⁵ .