JP2002062685A - Electrostatic latent image developing toner, image forming method and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide toners which do not give rise to the problems of drop-out defects of images, the degradation in a transfer rate and the toner filming to a photoreceptor with a contact transfer system and an image forming device. SOLUTION: This image forming method forms many sheets of the images by repeating respective process steps of transferring the toner images formed by developing the electrostatic latent images formed by subjecting the surface of the electrophotographic photoreceptor to electrostatic charge and image exposure with a developer containing the electrostatic latent image developing toners to a transfer material by using a contact transfer system then subjecting the transfer material to separating, fixing and cleaning, in which the electrostatic latent image developing toners are <=16% in the fluctuation coefficient of a shape coefficient. <=27% in the number fluctuation coefficient in a number grain side distribution and 3 to 35% in a flocculation rate of the toners.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic image developing toner (hereinafter, also simply referred to as "toner") used in a copying machine, a printer, and the like, and an image forming method and an image forming apparatus using the same.

[0002]

2. Description of the Related Art In a process of transferring a toner image formed on the surface of an electrophotographic photosensitive member (hereinafter, also simply referred to as a photosensitive member) to a paper or plastic sheet-like transfer material using a contact transfer method, a transfer roll, A transfer device including a drum or a belt is elastically pressed against the photosensitive member, and the transfer of the toner image is performed on the transfer material under application of a bias voltage.

However, the toner image is transferred directly to the transfer material via a conductive rubber roller using a conductive rubber or the like or a dielectric roller having a dielectric layer provided on the conductive rubber, and the toner image is transferred by an electric field generated thereby. In such a contact transfer method, a blank defect in a character often occurs in a process of transferring a toner image. This is related to the cohesive force or fluidity of the toners. It is known that a toner having a low cohesive force and a good fluidity of the toner is less likely to cause a void defect in a character. At present, effective means for resolving the void defect in characters has not yet been proposed.

In a transfer method for transferring a toner image from a photoreceptor to an intermediate transfer member and from the intermediate transfer member to a transfer material by an electric field,
Since a transfer current is applied, it is necessary to apply some pressure between the photoconductor and the intermediate transfer body. When pressure is applied, pressure is also applied to the toner image on the photoreceptor, and toner agglomeration is likely to occur and characters are likely to drop out.

Further, when the surface of the photoreceptor is made of a resin, adhesion occurs between the toner agglomerate and the photoreceptor, and the transfer to the transfer material is inhibited. In this case, the toner is fixed in the form of a film and image defects occur. Known toners are easily aggregated by pressurization, and it is difficult at present to prevent the occurrence of hollow defects, a decrease in transfer rate, and the prevention of toner filming on a photoconductor.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been proposed in view of the above problems.
When images are formed by the contact transfer method,
An object of the present invention is to provide a toner, an image forming method, and an image forming apparatus that do not cause a problem of a decrease in transfer rate and toner filming on a photosensitive member.

[0007]

The object of the present invention is attained by employing the invention as set forth in any one of claims 1 to 51. Means for solving the problems of the present invention mainly include the following items.

(1) A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer containing a toner for developing an electrostatic latent image is formed by a contact transfer method. In the image forming method of forming a large number of images by repeating the steps of transferring to a transfer material using a toner and then separating, fixing and cleaning, the toner for developing an electrostatic latent image has a shape factor Wherein the coefficient of variation is 16% or less, the coefficient of number variation in the number particle size distribution is 27% or less, and the toner aggregation rate is 3 to 35%.

(2) A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer containing a toner for developing an electrostatic latent image is formed by a contact transfer method. In the image forming method for forming a large number of images, the toner for developing an electrostatic latent image is transferred to a transfer material using The percentage of the toner particles not present is at least 50% by number,
An image forming method, wherein the number variation coefficient in the number particle size distribution is 27% or less and the toner aggregation rate is 3 to 35%.

(3) A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer containing a toner for developing an electrostatic latent image is formed by a contact transfer method. In the image forming method of forming a large number of images by repeating the steps of transferring to a transfer material using a toner and then separating, fixing and cleaning, the toner for developing an electrostatic latent image has a shape factor Wherein the number of toner particles is in the range of 1.2 to 1.6, the number of toner particles is 65% by number or more, the variation coefficient of the shape coefficient is 16% or less, and the toner aggregation rate is 3 to 35%.

(4) An intermediate transfer of a color toner image formed by developing an electrostatic latent image formed on the photoreceptor by performing charging and image exposure with a developer containing a toner for developing an electrostatic latent image. After transferring the image onto the body, the image is transferred from the intermediate transfer member to the transfer material using a contact transfer method, and then the separation, fixing, and cleaning steps are repeated to form an image forming method for forming a large number of images. Wherein the toner for developing an electrostatic latent image has a shape coefficient variation coefficient of 16% or less, a number variation coefficient in a number particle size distribution of 27% or less, and a toner aggregation rate of 3 to 35%. Image forming method.

(5) An intermediate transfer of a color toner image formed by developing an electrostatic latent image formed on the photoreceptor by performing charging and image exposure with a developer containing a toner for developing an electrostatic latent image. After transferring the image onto the body, the image is transferred from the intermediate transfer member to the transfer material using a contact transfer method, and then the separation, fixing, and cleaning steps are repeated to form an image forming method for forming a large number of images. Wherein the toner for developing an electrostatic latent image has a ratio of toner particles having no corners of 50% by number or more;
An image forming method, wherein the number variation coefficient in the number particle size distribution is 27% or less and the toner aggregation rate is 3 to 35%.

(6) An intermediate transfer of a color toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer containing a toner for developing an electrostatic latent image. After transferring the image onto the body, the image is transferred from the intermediate transfer member to the transfer material using a contact transfer method, and then the separation, fixing, and cleaning steps are repeated to form an image forming method for forming a large number of images. In the electrostatic latent image developing toner, the number of toner particles having a shape coefficient in the range of 1.2 to 1.6 is 65% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the toner aggregation rate Is 3 to 35%.

(7) A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer containing a toner for developing an electrostatic latent image is formed by a contact transfer method. The toner is used in an electrostatic latent image developing toner to be used in an image forming method for forming a large number of images by repeating the steps of transferring to a transfer material using an image forming method, and thereafter performing separation, fixing and cleaning. The latent image developing toner has a shape coefficient variation coefficient of 16% or less, a number variation coefficient in a number particle size distribution of 27% or less, and a toner aggregation rate of 3 to 35%. toner.

(8) A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer containing a toner for developing an electrostatic latent image is formed by a contact transfer method. The toner for developing an electrostatic latent image used in an image forming method for forming a large number of images by repeating the steps of transferring to a transfer material using The electrostatic latent image of the image developing toner is characterized in that the ratio of the toner particles having no corners is 50% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the toner aggregation rate is 3 to 35%. Development toner.

(9) A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer containing a toner for developing an electrostatic latent image is formed by a contact transfer method. The toner for developing an electrostatic latent image used in an image forming method for forming a large number of images by repeating the steps of transferring to a transfer material using The toner for image development has a shape factor of 1.2.
65% or more of toner particles in the range of 1.6 to 1.6, the coefficient of variation of the shape coefficient is 16% or less, and the toner aggregation rate is 3 to
35% of a toner for developing an electrostatic latent image.

(10) An image forming apparatus comprising the steps of cleaning, forming an electrostatic latent image, developing, transferring and fixing using the image forming method according to any one of the above items (1) to (6). .

Hereinafter, the present invention will be described in more detail. (1) Cause of image dropout When the surface of the photoreceptor is made of resin, adhesion occurs between the aggregate of toner and the photoreceptor, and transfer of the toner to the transfer material is hindered. In this case, a phenomenon in which a portion having strong adhesion is not transferred at all and an image is lost occurs.

This phenomenon occurs particularly remarkably in the line portion of 0.1 to 2.0 mm. This is because the edge phenomenon causes a large amount of toner in the line portion, and aggregation tends to occur due to pressure. The transferred image at this time is an image in which only the outline portion is formed, and an image defect called “hollow” occurs, which is a problem.

FIG. 1 shows an example of a void. In the figure, (a) is a normal image without a hollow portion, and (b) is a problem image in which a hollow portion occurs. (2) Decrease in transfer rate The transfer of the toner pressurized in the contact transfer section to the transfer material is inhibited, and the transfer rate is reduced by remaining on the photoreceptor surface. Since the toner not transferred to the transfer material does not contribute to image formation, the lower the transfer rate, the lower the image density, which is a problem. (3) Occurrence of toner filming The toner remaining on the surface of the photoconductor is removed by a cleaning blade. However, when the transfer rate decreases and the amount of toner remaining on the surface of the photoconductor increases, the amount of toner removed by the cleaning blade The cleaning blade increases the chance of rubbing the toner on the photoreceptor surface.
The rubbing causes a phenomenon (toner filming) in which the toner adheres to the surface of the photoconductor in a film shape. When toner filming occurs, fog image defects occur during actual shooting, which is a problem.

The present inventors have found that the variation coefficient of the shape factor of the toner, the number variation coefficient in the number particle size distribution, the agglomeration rate, and the like are important for solving the problems of the present invention, and complete the present invention. Reached.

It is presumed that the "hollow-out" of the character is caused by the toner aggregating at the time of pressing the transfer and remaining on the photoreceptor without being transferred, and various studies have been made on preventing the occurrence of toner agglomeration.
As a result, if the shape and circularity of the toner are uniform, the number of contact points between the toners decreases, and the form in which the corners of the toner enter the gaps between the toners also decreases, so that toner aggregation does not occur, and the occurrence of hollow holes is prevented. I found what I could do.

Also, a method for obtaining a high "transfer rate" of 90% or more is studied. If the shape and particle size of the toner sandwiched between the transfer material and the toner are positively supported by the transfer portion, the transfer material is uniform. It has been found that the distance between the transfer material and the photoreceptor is made uniform and minimized, a desired transfer electric field is applied, and a high transfer rate can be obtained.

Further, "toner filming" of the photosensitive member
Considering a method to prevent the occurrence, if the toner has a uniform shape and circularity, the adhesive force between the toner and the photoreceptor is evenly distributed, so that stress is not concentrated at one point, and the toner We found that filming could be prevented.

The inventors of the present invention have conducted intensive studies, and as a result, the toner has a specific shape and its distribution, agglutination rate, presence / absence of corners, and particle size distribution.
It has been found that even when a large number of images are formed, no "missing" of characters occurs, a high "transfer rate" can be secured, and "toner filming" does not occur on the photoreceptor.

The present inventors have conducted intensive studies and found that the "coefficient of variation of shape coefficient" is 16% or less, the "number variation coefficient in number particle size distribution" is 27% or less, and the "aggregation rate"
It has been found that the problem of the present invention can be solved by using a toner having a ratio of 3 to 35%, and the present invention has been completed. In other words, by achieving a uniform distribution of the shape of the toner itself, a high “transfer rate” is obtained,
It can suppress aggregation of the toner, prevent the occurrence of a “hollow-out” image defect due to transfer, and suppress “toner filming”.

The present inventors have conducted intensive studies, and have found that "toner particles having no corners" exhibit the same effect even if the dispersion of the shape is somewhat large because the toner aggregation resistance is improved. I found it. That is, the present invention has been completed by using a toner having 50% by number or more of toner particles without corners and having a number variation coefficient of 27% or less in a number particle size distribution.

FIG. 2 is a model diagram of toner (a) having no corner and toners (b) and (c) having corners.

Further, the present inventors have conducted intensive studies, and as a result,
It has been found that even when the specific shape is made uniform, the load applied to the toner and the photoreceptor in the transfer pressing portion can be made uniform, and the same effect can be exhibited.
That is, the variation coefficient of the shape coefficient is 16% or less, and the toner particles having the shape coefficient in the range of 1.2 to 1.6 are 65%.
It has been found that the purpose of the present invention can be solved by using a toner having a percentage of at least several percent, and the present invention has been accomplished.

The inventors of the present invention have studied toner particles having a large number of “voids” and “toner filming”. As a result, when the image forming process is repeated, toner particles and corners having irregular shapes are obtained. It has been found that toner particles having a portion cause "toner filming", and toner causing agglomeration at the time of transfer pressing tends to cause many "missing" image defects. Although the reason for this is not clear, it is presumed that in the case where the shapes of the toner particles are irregular, the stress is concentrated on one point of the photoconductor and the toner, and excessive stress is partially applied.

The difference in the manner in which the stress is applied also depends on the particle size of the toner particles, and the smaller the particle size, the higher the adhesion to the photoreceptor. It became. When the toner particle size is large, such a loss is reduced, but there is a problem that the image quality such as resolution is deteriorated.

As a result of an examination from the above viewpoints, it is necessary to use a toner having a shape coefficient variation coefficient of 16% or less, a number variation coefficient in a number particle size distribution of 27% or less, and a toner aggregation rate of 3 to 35%. The present inventors have found that a high-quality image can be formed over a long period of time with excellent transfer rate and fine line reproducibility, and the present invention has been completed.

Also, by controlling the toner particles having no corners to 50% by number or more and controlling the number variation coefficient in the number and particle size distribution to 27% or less, the transfer rate and the fine line reproducibility are improved, and a high-quality image can be obtained for a long time. And found that the present invention was completed.

Further, it has been found that even when the toner is made to have a specific shape and the shapes are aligned, the "toner filming" and "missing" image defects are reduced. That is, toner particles having a shape coefficient in the range of 1.2 to 1.6 are 65% by number or more, and the variation coefficient of the shape coefficient is 16%.
By using the following toner, it was found that a high-quality image could be formed over a long period of time with excellent transfer rate and fine line reproducibility, and the present invention was completed.

The shape factor of the toner of the present invention is represented by the following equation (1) and indicates the degree of roundness of toner particles.

Equation (1) Shape factor = ((maximum diameter / 2) ²
× π) / projected area In the formula, the maximum diameter indicates the width of the particle at which the interval between the parallel lines is maximum when the projected image of the toner particles on the plane is separated by two parallel lines. The projection area indicates the area of the projected image of the toner particles on the plane.

The shape factor was determined by scanning electron microscope.
Take a photo with the toner particles magnified by a factor of 00, and then "SCANNING IMAGE ANALYZER"
(Manufactured by JEOL Ltd.) to analyze the photographic image. The shape factor was obtained by analyzing 100 toner particles.

In the above items (1) and (2),
The number of toner particles having a shape factor in the range of 1.0 to 1.6 is preferably 65% by number or more, more preferably 70% by number or more.

When the number of toner particles having a shape factor in the range of 1.0 to 1.6 is at least 65% by number, the triboelectrification of the developer conveying member or the like becomes more uniform, and the excessively charged toner Is not accumulated, and the toner is more easily exchanged than the surface of the developer conveying member. Therefore, problems such as a development ghost are less likely to occur. Further, the toner particles are less likely to be crushed, so that the contamination of the charging member is reduced, and the charging property of the toner is stabilized.

In the above item (3), toner particles having a shape factor in the range of 1.2 to 1.6
It is necessary to be at least several%, preferably 70%
It is more than the number%.

The method of controlling the shape factor is not particularly limited. Specifically, a method of spraying toner particles into a hot air flow, a method of repeatedly applying mechanical energy by an impact force in a gas phase, or a method of adding a toner particle in a solvent that does not dissolve a toner to provide a swirling flow The shape factor is set to 1.0 to 1.6 or 1.2 to
There is a method in which a 1.6-toner is prepared and added to a normal toner so as to fall within the scope of the present invention. Further, the whole shape is controlled at the stage of producing the polymerization toner, and the shape factor is set to 1.0 to 1.6 or 1.2 to 1.6.
In the same manner, there is a method in which the toner prepared as described above is added to a normal toner.

Among the above methods, a polymerization toner is preferred because it is simple as a production method and has excellent surface uniformity as compared with a pulverized toner.

The variation coefficient of the shape factor of the toner of the present invention is calculated from the following equation (2). Equation (2) Coefficient of variation = (S / K) × 100 (%) In the equation, S represents the standard deviation of the shape coefficient of 100 toner particles, and K represents the average value of the shape coefficient.

The variation coefficient of the shape factor is 16% or less, preferably 14% or less. When the coefficient of variation of the shape factor is 16% or less, the voids in the transferred toner layer are reduced, the transfer rate is improved, and “voids” and “toner filming” are less likely to occur. Further, the charge amount distribution becomes sharp, and the image quality is improved.

In order to uniformly control the shape factor and the variation coefficient of the shape factor when manufacturing the polymerized toner without variation in lots, the resin particles (polymer particles) are polymerized, fused and controlled in shape. In the process, it is preferable to determine an appropriate process end time while monitoring characteristics of toner particles (colored particles) being formed.

Monitoring means that a measuring device is incorporated in-line and the process conditions are controlled based on the measurement result.

That is, in the case of a polymerization toner produced by incorporating a measuring device for shape and the like in-line and, for example, associating or fusing resin particles in an aqueous medium, successive sampling is performed in a process such as fusing. Measure the shape and particle size,
The reaction is stopped when the desired shape or particle size is reached.

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 measurement sample is taken out from the reactor using a pump or the like, and is constantly monitored to measure the shape and the like, and the reaction is stopped when the desired shape and the like are obtained.

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

The number particle size distribution and number average particle size were calculated using a computer from data measured by setting an aperture having a diameter of 100 μm 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 is
It represents the median diameter in the number particle size distribution.

The number variation coefficient in the number particle size distribution of the toner is calculated from the following equation (3). Formula (3) Number variation coefficient = (S / Dn) × 100 (%) In the formula, S represents a standard deviation in the number particle size distribution, and Dn
Indicates a number average particle size (μm).

The number variation coefficient of the toner of the present invention is 27% or less, preferably 25% or less. When the number variation coefficient is 27% or less, the gap of the transferred toner layer is reduced, the fixing property is improved, and the offset is less likely to occur. Further, the charge amount distribution becomes sharp, a high transfer rate is obtained, and the image quality is improved.

The method for controlling the number variation coefficient 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 the liquid, there is a method in which a centrifugal separator is used to separate and collect toner particles in accordance with a difference in centrifugal sedimentation speed caused by a difference in toner particle diameter by controlling a rotation speed.

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

The toner particles having no corners according to the present invention refer to toner particles having substantially no projections on which electric charges are concentrated or projections which are easily worn by stress. The particles are called cornerless toner particles.

That is, as shown in FIG. 2, when the inside of the toner particle is rolled while being in contact with the inside of the toner particle at one point with a circle having a major axis of L and a radius R of L / 10, The case where the circle does not substantially extend outside the toner is referred to as “cornerless toner particles”. The case where the protrusion does not substantially protrude means that one or more protrusions have a protruding circle. Further, the major axis of the toner particle means the width of the particle at which the interval between the parallel lines becomes maximum when the projected image of the toner particle on the plane is sandwiched between two parallel lines.

The measurement of the toner having no corner was performed as follows. First, a photograph in which the toner particles are enlarged is taken by a scanning electron microscope, and further enlarged to obtain a photographic image of 15,000 times. Next, the presence or absence of the corners is measured for this photographic image. This measurement was performed for 100 toner particles.

In the toner of the present invention, the ratio of toner particles having no corner is preferably at least 50% by number, more preferably at least 70% by number. When the ratio of the toner particles having no corners is 50% by number or more, generation of fine particles due to stress with the developer conveying member or the like is eliminated, and so-called excessively adherent toner to the surface of the developer conveying member is present. Can be prevented, contamination of the developer conveying member can be suppressed, and the charge amount can be sharpened. Also, the amount of toner particles that are liable to be worn or broken and the number of toner particles having a portion where charges are concentrated are reduced, the charge amount distribution becomes sharp, the chargeability is stabilized, and good image quality can be formed over a long period of time. I can do it.

The method for obtaining a toner having no corners is not particularly limited. Specifically, a method of spraying toner particles into a hot air flow, a method of repeatedly applying mechanical energy by an impact force in a gas phase, or a method of adding a toner particle to a solvent that does not dissolve the toner, And the like.

In a polymerization toner formed by associating or fusing resin particles, the surface of the fused particles has many irregularities at the stage of stopping the fusion, and the surface is not smooth. By appropriately controlling conditions such as the temperature in the process, the number of rotations of the stirring blade, and the stirring time, a toner having no corners can be obtained. These conditions vary depending on the physical properties of the resin particles. For example, by rotating at a high temperature at a temperature equal to or higher than the glass transition point of the resin particles, the surface becomes smooth and a toner having no corners can be formed.

The particle diameter of the toner used in the present invention is preferably from 2.2 to 9 μm, more preferably from 3 to 8 μm in number average particle diameter. The particle size is determined by the conditions of pulverization and classification when toner particles are formed by a pulverization method, and the concentration of an aggregating agent or the amount of an organic solvent added when fusing toner particles by a polymerization method, or the fusing time. Can be controlled by the composition of the polymer itself.

When the number average particle diameter is 2.2 to 9 μm, it is possible to reduce the presence of a toner having an excessive adhesive force or a toner having a low adhesive force to the developer conveying member in the developing step. In addition, the developability can be stabilized for a long time, a high transfer rate can be obtained, and the image quality of fine lines, dots, and the like can be improved.

In the toner of the present invention, when the particle size of the toner particles is D (μm), the natural logarithm InD is plotted on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23. In the histogram showing the particle size distribution, the “relative frequency (m1) of the toner particles included in the most frequent class and the relative frequency (m2) of the toner particles included in the class having the next highest frequency after the most frequent class are described. Sum (M) "is preferably 70% or more.

When the “sum (M) of the relative frequency (m1) and the relative frequency (m2)” is 70% or more, the dispersion of the particle size distribution of the toner particles becomes narrow, and the toner is used in the image forming process. By using this, the occurrence of selective development can be suppressed.

In the histogram showing the number-based particle size distribution, the natural logarithm lnD (D: particle size of individual toner particles) is divided into a plurality of classes (0 to 0.23: 0.
23-0.46: 0.46-0.69: 0.69-0.
92: 0.92 to 1.15: 1.15 to 1.38: 1.
38-1.61: 1.61-1.84: 1.84-2.
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 obtained by analyzing the particle size data of the sample measured by the Coulter Multisizer in accordance with the following measurement conditions. The program is transferred to a computer via a unit, and is created by the computer using a particle size distribution analysis program.

Measurement conditions (1) Measurement aperture diameter: 100 μm (2) Sample preparation: Electrolyte (ISOTON R-11)
(Coulter Scientific Japan) 5
An appropriate amount of a surfactant (neutral detergent) is added to 0 to 100 mL, and the mixture is stirred, and 10 to 20 mg of a measurement sample is added thereto. The measurement liquid is prepared by subjecting this system to a dispersion treatment with an ultrasonic disperser for one minute.

The aggregation rate of the toner of the present invention is 3 to 35%, preferably 8 to 22%, more preferably 9 to 22%.
18%. If it is less than 3%, the fluidity of the toner is too good, and the toner is scattered in the apparatus to cause contamination in the apparatus, which is not preferable. On the other hand, if it exceeds 35%, "hollow-out" occurs and "transfer rate" decreases, which is not preferable.

The agglomeration rate is obtained by applying the mass of the toner remaining on the sieve by the following measuring method to the following equation (4).

The measurement of the agglomeration rate is carried out by preliminarily measuring the temperature of the toner at 20.degree.
Leave in an environment of 0% RH for 12 hours or more, and in the same environment, use a powder tester (manufactured by Hosokawa Micron Co., Ltd.) with a sieve of 1:45 μm, a sieve of 2:75 μm, and a sieve of 3: 150 μm.
Set the test sieve on the step, fix it with the holding bar and the knob nut, set the swing width to 1 mm, weigh 2 g of the toner, put it on the top sieve 3 and apply vibration for 90 seconds to obtain the amount on the sieve It is done by doing.

Formula (4) Aggregation ratio = A + B + CA A = mass of toner remaining on sieve 3 × 100/2 B = mass of toner remaining on sieve 2 × 100/2 × 3/5 C = remaining on sieve 1 The mass of the toner x 100/2 x 1/5 (Toner) The toner preferably used in the present invention is obtained by suspension polymerization or emulsion polymerization of a monomer in a liquid to which an emulsion of necessary additives is added. , To produce fine polymer particles, and then
It can be produced by a method of associating by adding an organic solvent, a flocculant and the like. A method of preparing a toner by mixing with a dispersion liquid such as a release agent or a colorant necessary for the composition of the toner at the time of association and preparing the mixture, or dispersing a toner component such as a release agent or a colorant in a monomer. And then emulsion polymerization. Here, the association means that a plurality of resin particles and colorant particles are fused.

That is, various constituent materials such as a colorant and, if necessary, a release agent, a charge control agent, and a polymerization initiator are added to the polymerizable monomer, and a homogenizer, a sand mill, a sand grinder, and an ultrasonic disperser are added. Various constituent materials are dissolved or dispersed in the polymerizable monomer by a machine or the like. The polymerizable monomer in which the various constituent materials are dissolved or dispersed is dispersed in an aqueous medium containing a dispersion stabilizer into oil droplets having a desired size as a toner by using a homomixer, a homogenizer, or the like. Thereafter, the stirring mechanism is moved to a reaction device that is a stirring blade described below,
The polymerization reaction is advanced by heating. After completion of the reaction, the toner of the present invention is prepared by removing the dispersion stabilizer, filtering, washing and drying.

The aqueous medium in the present invention means a medium containing at least 50% by mass of water.

Further, as a method of producing the toner of the present invention, a method of preparing by associating or fusing resin particles in an aqueous medium can also be mentioned. Although this method is not particularly limited, for example, Japanese Patent Application Laid-Open No. 5-2652
52, JP-A-6-329947 and JP-A-9
-15904 can be mentioned.
That is, dispersed particles of constituent materials such as resin particles and colorant,
Alternatively, a method of associating a plurality of fine particles composed of a resin, a colorant, and the like, particularly after dispersing these in water using an emulsifier, adding a coagulant having a critical coagulation concentration or more and performing salting out, The polymer itself is heated and fused at a temperature equal to or higher than the glass transition temperature to gradually grow the particle size while forming fused particles, and when the target particle size is reached, a large amount of water is added to stop the particle size growth. The toner can be formed by further smoothing the surface of the particles while heating and stirring to control the shape, and heating and drying the particles in a fluid state while keeping the particles in a water-containing state. Here, an organic solvent which is infinitely soluble in water may be added together with the coagulant.

As the polymerizable monomer constituting the resin, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene, 3,4- Dichlorostyrene,
p-phenylstyrene, p-ethylstyrene, 2,4-
Dimethylstyrene, p-tert-butylstyrene, p
-N-hexylstyrene, pn-octylstyrene,
pn-nonylstyrene, pn-decylstyrene, p
Styrene or a styrene derivative such as n-dodecylstyrene, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-octyl methacrylate, methacrylic acid 2 -Ethylhexyl, stearyl methacrylate, lauryl methacrylate,
Methacrylate derivatives such as phenyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, isobutyl acrylate, acrylic N-octyl acid, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate, phenyl acrylate and the like, acrylate derivatives, olefins such as ethylene, propylene and isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide, Halogen vinyls such as vinyl fluoride and vinylidene fluoride, vinyl esters such as vinyl propionate, vinyl acetate and vinyl benzoate, and vinyl ethers such as vinyl methyl ether and vinyl ethyl ether , Vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl hexyl ketone, N-vinyl compounds such as N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone, vinyl compounds such as vinyl naphthalene and vinyl pyridine, There are acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide. These vinyl monomers can be used alone or in combination.

Further, it is more preferable to use a polymerizable monomer constituting the resin in combination with one having an ionic dissociation group. For example, those having a substituent such as a carboxyl group, a sulfonic acid group, and a phosphoric acid group as a constituent group of a monomer, specifically, acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, and fumaric acid. Acid, maleic acid monoalkyl ester, itaconic acid monoalkyl ester, styrenesulfonic acid, allylsulfosuccinic acid, 2-acrylamido-2-methylpropanesulfonic acid, acid phosphooxyethyl methacrylate, 3
-Chloro-2-acid phosphooxypropyl methacrylate and the like.

Further, divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate,
Polyfunctional vinyls such as neopentyl glycol diacrylate can be used to form a crosslinked resin.

These polymerizable monomers can be polymerized using a radical polymerization initiator. In this case, an oil-soluble polymerization initiator can be used in the suspension polymerization method. As the oil-soluble polymerization initiator, 2,2'-azobis- (2,4
-Dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvalero Nitroles, azo or diazo polymerization initiators such as azobisisobutyronitrile,
Benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis- (4
4-tert-butylperoxycyclohexyl) propane,
Examples include peroxide-based polymerization initiators such as tris- (t-butylperoxy) triazine and polymer initiators having a peroxide in a side chain.

When the emulsion polymerization method is used, a water-soluble radical polymerization initiator can be used. Examples of the water-soluble polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetate, azobiscyanovaleric acid and salts thereof, and hydrogen peroxide.

Examples of the dispersion stabilizer include tricalcium phosphate, magnesium phosphate, zinc phosphate, aluminum phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, and calcium sulfate. , Barium sulfate,
Bentonite, silica, alumina and the like can be mentioned. Further, those generally used as surfactants such as polyvinyl alcohol, gelatin, methyl cellulose, sodium dodecylbenzenesulfonate, ethylene oxide adduct, and higher alcohol sodium sulfate can be used as the dispersion stabilizer.

As the excellent resin in the toner used in the present invention, those having a glass transition point of 20 to 90 ° C. and those having a softening point of 80 to 220 ° C. are preferable. The glass transition point is measured by a differential calorimetric analysis method, and the softening point can be measured by a Koka type flow tester. Further, as these resins, those having a number average molecular weight (Mn) of 1,000 to 100,000 and a mass average molecular weight (Mw) of 2,000 to 1,000,000 as measured by gel permeation chromatography are preferred. Further, as a molecular weight distribution, Mw / Mn is 1.5
To 100, particularly preferably 1.8 to 70.

The coagulant used is not particularly limited, but those selected from metal salts are preferably used. Specifically, as a monovalent metal, for example, a salt of an alkali metal such as sodium, potassium, and lithium, and as a divalent metal, for example, a salt of an alkaline earth metal such as calcium and magnesium, or a divalent metal such as manganese or copper Salt,
Examples include salts of trivalent metals such as iron and aluminum, and specific salts include sodium chloride, potassium chloride, lithium chloride, calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, and manganese sulfate. Can be done.
These may be used in combination.

These coagulants are preferably added at a concentration higher than the critical coagulation concentration. The critical aggregation concentration is an index relating to the stability of the aqueous dispersion, and indicates the concentration at which aggregation occurs when a coagulant is added. This critical aggregation concentration is
It varies greatly depending on the emulsified component and the dispersant itself. For example, Seizo Okamura et al., “Polymer Chemistry 1
7, 601 (1960), edited by The Society of Polymer Science, Japan, etc., and a detailed critical aggregation concentration can be determined.
As another method, a desired salt is added to the target particle dispersion at a different concentration, and the ζ (zeta) potential of the dispersion is measured. The salt concentration at which this value changes is defined as the critical aggregation concentration. You can also ask.

The amount of the coagulant used in the present invention may be at least the critical coagulation concentration, but is preferably at least 1.2 times, more preferably at least 1.5 times the critical coagulation concentration. Good.

The solvent which is infinitely soluble means a solvent which is infinitely soluble in water, and a solvent which does not dissolve the formed resin in the present invention is selected.
Specifically, methanol, ethanol, propanol,
Examples thereof include alcohols such as isopropanol, t-butanol, methoxyethanol and butoxyethanol, nitriles such as acetonitrile, and ethers such as dioxane. Particularly, ethanol, propanol and isopropanol are preferred.

The amount of the solvent to be dissolved infinitely is 1 to 100% by volume based on the polymer-containing dispersion to which the flocculant has been added.
Is preferred.

In order to make the shape uniform, it is preferable to prepare a colored particle, and after the filtration, a slurry in which water is present in an amount of 10% by mass or more with respect to the particle is preferably fluidized and dried. Those having a polar group in the polymer are preferred. It is considered that the reason for this is that the existing water exerts an effect of slightly swelling the polymer in which the polar group is present, so that it is particularly easy to make the shape uniform.

The toner used in the present invention contains a resin and a colorant. If necessary, the toner may contain a releasing agent or a charge control agent as a fixing property improving agent. Further, an external additive composed of inorganic fine particles, organic fine particles, and the like may be added to the toner particles containing the resin and the colorant as main components.

As the colorant used in the toner used in the present invention, carbon black, magnetic substance, dye, pigment and the like can be used arbitrarily. As the carbon black, channel black, furnace black, acetylene black, thermal black and the like can be used. , Lamp black and the like are used. As the magnetic material, ferromagnetic metals such as iron, nickel and cobalt, alloys containing these metals, compounds of ferromagnetic metals such as ferrite and magnetite, alloys which do not contain ferromagnetic metals but show ferromagnetism by heat treatment, For example, alloys of a type called a Heusler alloy such as manganese-copper-aluminum and manganese-copper-tin, chromium dioxide, and the like can be used.

As the dye, C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 1
22, C.I. I. Solvent Yellow 19, 44, 7
7, 79, 81, 82, 93, 98, 10
3, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93, 9
5 and the like, and mixtures thereof can also be used. Examples of the pigment include C.I. I. Pigment Red 5, 48: 1, 53: 1, 57: 1, 122,
139, 144, 149, 166, 177,
178, 222, C.I. I. Pigment Orange 3
1, 43, C.I. I. Pigment Yellow 14, 1
7, 93, 94, 138, C.I. I. Pigment Green 7, C.I. I. Pigment Blue 15: 3, 60
And the like, and mixtures thereof can also be used. Although the number average primary particle size varies depending on the type,
It is preferably about 10 to 200 nm.

As a method of adding a colorant, a method of adding polymer particles prepared by an emulsion polymerization method at the stage of aggregation by adding an aggregating agent to color the polymer, or a stage of polymerizing a monomer. A method in which a coloring agent is added, polymerized to form colored particles, or the like can be used. When the colorant is added at the stage of preparing the polymer, it is preferable to use the colorant after treating the surface with a coupling agent or the like so as not to inhibit the radical polymerizability.

Further, low molecular weight polypropylene (number average molecular weight = 1500 to 9000), low molecular weight polyethylene or the like may be added as a fixing property improving agent.

The charge control agents are also various known ones.
In addition, those that can be dispersed in water can be used. Specific examples include a nigrosine dye, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylated amine, a quaternary ammonium salt compound, an azo metal complex, a metal salt of salicylic acid, and a metal complex thereof.

The particles of the charge controlling agent and the fixability improving agent have a number average primary particle diameter of 10 to 500 in a dispersed state.
It is preferable to set it to about nm.

In a suspension polymerization method toner in which a toner component such as a colorant is dispersed or dissolved in a so-called polymerizable monomer is suspended in an aqueous medium and then polymerized to obtain a toner. By controlling the flow of the medium in the reaction vessel, the shape of the toner particles can be controlled. That is, when a large number of toner particles having a shape factor of 1.2 or more are formed, the flow of the medium in the reaction vessel is made turbulent, and the polymerization proceeds to be present in the aqueous medium in a suspended state. When the oil droplets gradually become polymerized, the oil droplets become soft particles, and when the oil droplets collide, the particles collide to promote the coalescence of the particles, resulting in particles with an irregular shape . When spherical toner particles having a shape factor smaller than 1.2 are to be formed, spherical particles can be obtained by using a medium flow in the reaction vessel as a laminar flow to avoid collision of the particles. By this method, the distribution of the toner shape can be controlled within the scope of the present invention.

In the suspension polymerization method, by using a specific stirring blade, a turbulent flow can be formed, and the shape can be easily controlled. The reason for this is that, although it is not clear, when the configuration of the commonly used stirring blade as shown in FIG. 3 is one stage, the flow of the medium formed in the stirring tank is higher than the lower part of the stirring tank. Only the flow that moves along the wall to Therefore, conventionally, a turbulence is generally formed by disposing a baffle plate such as a wall surface of a stirring tank, and the efficiency of stirring is increased. However, in such a device configuration, although a turbulent flow is partially formed, the turbulent flow acts in a direction in which the flow of the fluid stagnates, and as a result, the slip with respect to the particles is reduced. Can't control.

A stirring tank having a stirring blade which can be preferably used will be described with reference to the drawings.

FIG. 3 is a schematic view showing an example of a stirring tank provided with a stirring blade commonly used in the prior art. FIG. 4 is a schematic view showing an example of a stirring tank provided with a more preferable stirring blade. A rotating shaft 3 is suspended from the center of a vertical cylindrical stirring tank 2 having a heat exchange jacket 1 attached to the outer periphery of the stirring tank, and the rotating shaft 3 is brought close to the bottom surface of the stirring tank 2. There is a lower stirring blade 4 disposed therein and a stirring blade 5 disposed higher in the stage. The upper-stage stirring blade 5 is disposed at a crossing angle α that precedes the rotation direction with respect to the lower-stage stirring blade 4. In the present invention, the intersection angle α is preferably less than 90 degrees. The lower limit of this intersection angle is not particularly limited, but is about 5 ° or more,
Preferably, it should be at least 10 degrees. FIG. 5 shows this in a top sectional view. If there are three or more stages, the intersection angle α between the adjacent stirring blades may be less than 90 degrees.

[0098] With this configuration, the medium is first stirred by the stirring blades arranged in the upper stage, and a flow to the lower side is formed. Next, by the stirring blade arranged in the lower stage,
It is presumed that the flow formed by the upper stirring blade is further accelerated downward, and a downward flow is separately formed by the stirring blade itself, so that the flow is accelerated as a whole and proceeds. As a result, it is presumed that a basin having a large shear stress formed as a turbulent flow is formed, so that the shape of the toner can be controlled.

In FIG. 4, the arrow indicates the rotation direction, 7 indicates the upper material input port, and 8 indicates the lower material input port. Reference numeral 9 denotes a turbulence forming member for making the stirring effective.

FIG. 5 is a top sectional view of FIG. Here, the shape of the stirring blade is not particularly limited, but is a square plate, a notch in a part of the blade, and a center portion having one or more middle holes, so-called slits. Etc. can be used.

FIG. 6 is a schematic diagram showing the shape of the stirring blade. FIG.
The middle (a) has no stirring hole in the stirring blade, (b) has a large middle hole 6 in the center, (c) has a horizontally long middle hole 6, and (d) has a vertically long hole. It has a hole 6.
Further, these may be different from each other in the upper hole and the lower hole, or may be the same.

FIGS. 7 to 11 show examples of preferable structures which can be used as the structure of the stirring blade.

FIG. 7 is a schematic view of a stirring tank having a slit in a lower stirring blade and a bent and projected end.

FIG. 8 is a schematic view of a stirring tank having a projection at the end of the stirring blade and / or a bent portion at the end.

FIG. 9 is a schematic view of a stirring tank having three stages of stirring blades. FIG. 10 shows an outline of a stirring tank having a gap in an upper stirring blade and having a bent portion and a projection at an end of the lower stirring blade.

FIG. 11 shows a stirring tank having a projection at the end of the upper stirring blade and a bend at the end of the lower stirring blade. The angle of the bent portion at the end of the stirring blade is 5 to 45.
Degree is preferable.

The agitating blade having the structure having the bent portion and the upper or lower protrusion effectively generates turbulence.

The gap between the upper and lower stirring blades having the above configuration is not particularly limited, but it is preferable to have a gap between the stirring blades. Although the reason is not clear, it is considered that the flow of the medium is formed through the gap, so that the stirring efficiency is improved. However, the gap is set at 0. 0 relative to the liquid level in the stationary state.
The width is 5 to 50%, preferably 1 to 30%.

Furthermore, the size of the stirring blade is not particularly limited, but the sum of the heights of all the stirring blades is 50 to 100%, preferably 60 to 95% of the liquid level in the stationary state. Is good.

FIG. 4 shows an example of a stirring blade and a stirring tank used for forming a laminar flow in the suspension polymerization method. It is characterized in that an obstacle such as a baffle plate that forms a turbulent flow is not provided in the stirring tank. Regarding the configuration of the stirring blade, similarly to the stirring blade used for forming the above-described turbulent flow, the upper stirring blade is arranged with the intersection angle α preceding the lower stirring blade in the rotation direction. It is preferable to provide a multi-stage configuration.

The shape of the stirring blade is not particularly limited as long as it does not form a turbulent flow. However, the shape of the stirring blade is preferably formed by a continuous surface such as a rectangular plate-like one in FIG. May be.

On the other hand, in the case of a polymerization toner in which resin particles are associated or fused in an aqueous medium, the flow and temperature distribution of the medium in the reaction vessel at the fusion stage are controlled to further improve the shape after fusion. In the control process, heating temperature, stirring speed,
By controlling the time, the shape distribution and shape of the entire toner can be arbitrarily changed.

That is, in the case of the polymerization toner in which the resin particles are associated or fused, the flow in the reaction apparatus is made laminar, and the stirring blade and the stirring tank which can make the internal temperature distribution uniform are used. By controlling the temperature, the number of rotations, and the time in the deposition step and the shape control step, it is possible to form a toner having the shape factor and uniform shape distribution of the present invention. The reason for this is that if you fuse in a place where a laminar flow is formed,
No strong stress is applied to the particles (aggregated or aggregated particles) that are undergoing aggregation and fusion, and the temperature distribution in the stirred tank is uniform in a laminar flow with accelerated flow,
It is estimated that the shape distribution of the fused particles becomes uniform. Furthermore, the fused particles gradually become spherical by heating and stirring in the subsequent shape control step, and the shape of the toner particles can be arbitrarily controlled.

As a stirring blade and a stirring tank used for a polymerization toner for associating or fusing resin particles, the same stirring blades as those used in the case of forming a laminar flow in the above-mentioned suspension polymerization method can be used. The one shown in FIG. 11 can be used. It is characterized in that no obstacle such as a baffle plate which forms a turbulent flow is provided in the stirring tank. Regarding the configuration of the stirring blade, similarly to the stirring blade used in the above-mentioned suspension polymerization method, the upper stirring blade is disposed with the intersection angle α preceding the lower stirring blade in the rotation direction. In addition, a multi-stage configuration is preferable.

The shape of the stirring blade may be the same as that in the case of forming a laminar flow in the above-mentioned suspension polymerization method, and is not particularly limited as long as it does not form a turbulent flow. It is preferably formed by a continuous surface, such as a square plate, and may have a curved surface.

The toner of the present invention can be used by adding fine particles such as inorganic fine particles and organic fine particles as an external additive. By adding an external additive, it is possible to improve the fluidity of the toner and maintain the charging characteristics.

As the inorganic fine particles, it is preferable to use inorganic oxide particles such as silica, titania and alumina.
Further, it is preferable that these inorganic fine particles have been subjected to a hydrophobic treatment with a silane coupling agent, a titanium coupling agent, or the like. The degree of the hydrophobization treatment is not particularly limited, but a hydrophobization degree (methanol wettability) of 40 to 95 is preferable. Methanol wettability is to evaluate the wettability to methanol. In this method, 0.2 g of the inorganic fine particles to be measured is weighed and added to 50 mL of distilled water placed in a 200 mL beaker. Methanol is slowly dropped from a burette whose tip is immersed in the liquid until the whole of the inorganic fine particles is wet with stirring slowly. Assuming that the amount of methanol required to completely wet the inorganic fine particles is a (mL), the degree of hydrophobicity is calculated by the following equation (5).

Formula (5) Degree of hydrophobicity = (a / (a + 50)) × 100 The amount of the external additive is preferably 0.1 to 0.1 in the toner.
To 5.0% by mass, more preferably 0.5 to 4.0% by mass.
It is. Also, various external additives may be used in combination.

Next, regarding the numerical values according to the present invention, numerical values of conventionally known toners will be described. This value differs depending on the manufacturing method.

In the case of a toner produced by a pulverization method, the number of toner particles having a shape coefficient in the range of 1.2 to 1.6 is about 60% by number. The coefficient of variation of the shape factor is 20
%. Further, in the pulverization method, since the particle size is reduced while crushing is repeated, the toner particles have many corners, and the ratio of toner particles without corners is 30% by number or less. Therefore, in order to obtain a rounded toner having no corners and a uniform shape, it is necessary to perform a process of forming a spherical shape by heat or the like as described above as a method of controlling the shape coefficient. The number variation coefficient in the number particle size distribution is about 30% when the classification operation after the pulverization is performed once,
In order to reduce the number variation coefficient to 27% or less, it is necessary to repeat the classification operation.

In the case of a toner produced by a suspension polymerization method,
Conventionally, since polymerization is carried out in a laminar flow, substantially spherical toner particles are obtained. For example, in the toner described in JP-A-56-130762, the shape factor is 1.2 to 1.
The number of toner particles in the range of 6 is about 20% by number, the variation coefficient of the shape coefficient is also about 18%, and the ratio of toner particles without corners is also about 85% by number. Further, as described in the method of controlling the number variation coefficient in the number particle size distribution, a large oil droplet of a polymerizable monomer is repeatedly mechanically sheared to reduce the oil droplet to a size of a toner particle. In addition, the distribution of oil droplet diameters is widened, and the particle size distribution of the obtained toner is wide, and the coefficient of variation in number is as large as about 32%. A classification operation is required to reduce the coefficient of variation in number.

In the case of a toner produced by a polymerization method formed by associating or fusing resin particles, for example, in a toner described in JP-A-63-186253,
The toner particles having a shape factor in the range of 1.2 to 1.6 are 6
It is about 0% by number, the variation coefficient of the shape factor is about 18%, and the ratio of the toner particles without corners is 55% by number.
It is about. Further, the particle size distribution of the toner is wide, and the number variation coefficient in the number particle size distribution is 30%, and a classification operation is required to reduce the number variation coefficient.

(Photoreceptor) The photoreceptor used in the present invention comprises:
A photosensitive layer is provided on a conductive support, wherein the photosensitive layer comprises an undercoat layer and a surface layer, the surface layer comprises a charge generation layer and a charge transport layer, and the surface layer of the photosensitive layer is an average. It contains a polycarbonate having a molecular weight of 10,000 to 100,000. Preferably, the photoconductor has a surface protective layer, and the surface protective layer contains a siloxane resin having a crosslinked structure, and more preferably, the surface protective layer containing the siloxane resin has a charge transporting structural unit. Is included in a part of the crosslinked structure.

As the binder resin for the surface layer, it is preferable to use polycarbonate having an average molecular weight of 10,000 to 100,000 in terms of toner filming resistance and the like.
If the average molecular weight of the polycarbonate is less than 10,000, the film strength of the surface layer becomes weak, and if it exceeds 100,000, the surface layer becomes uneven, which is not preferable.

The surface protective layer containing a siloxane resin is preferable from the viewpoints of extending the life of the photosensitive member and preventing toner filming from occurring.

The layer structure of the photoreceptor used in the present invention is not particularly limited, but may be a charge generation layer, a charge transport layer, or a charge generation / charge transport layer (a single layer having both functions of charge generation and charge transport). (A photosensitive layer) and a protective layer provided thereon. Further, the charge generation layer,
Each layer of the charge transport layer or the charge generation / transport layer may be composed of a plurality of layers.

The charge generation material (CG) contained in the photosensitive layer
Examples of M) include phthalocyanine pigments, polycyclic quinone pigments, azo pigments, perylene pigments, indigo pigments, quinacridone pigments, azurenium pigments, squalilium dyes,
Cyanine dye, pyrylium dye, thiopyrylium dye,
Xanthene dyes, triphenylmethane dyes, styryl dyes and the like can be mentioned, and these charge generating substances (CGM) are used alone or together with a suitable binder resin to form a layer.

The charge transport material (C) contained in the photosensitive layer
TM) include, for example, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazoline derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds, benzidine compounds, pyrazoline derivatives, stilbenes Compound,
Amine derivatives, oxazolone derivatives, benzothiazole derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostilbene derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, etc. These charge transport materials (CTM) are usually used to form a layer together with a binder.

As the binder resin contained in the charge generating layer (CGL) and the charge transport layer (CTL) in the case of the photosensitive layer having a single layer structure and the laminate structure, polycarbonate resin, polyester resin, polystyrene resin, methacrylic resin,
Acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl butyral resin, polyvinyl acetate resin, styrene-butadiene resin, vinylidene chloride-acrylonitrile copolymer resin, vinyl chloride-maleic anhydride copolymer resin, urethane resin, silicone Resins, epoxy resins, silicone-alkyd resins, phenol resins, polysilane resins, polyvinyl carbazole, and the like.

In the present invention, the ratio between the charge generating substance and the binder resin in the charge generating layer is from 1: 5 to 5: 1 by mass.
Is preferred. The thickness of the charge generation layer is preferably 5 μm or less, and particularly preferably 0.05 to 2 μm.

The charge transport layer is formed by dissolving the charge transport material and the binder resin in a suitable solvent, and applying and drying the solution. The mixing ratio of the charge transport material and the binder resin is preferably from 3: 1 to 1: 3 by mass ratio.

The thickness of the charge transport layer is usually from 5 to 50 μm, preferably from 10 to 40 μm. When a plurality of charge transport layers are provided, the thickness of the upper layer of the charge transport layer is 10 μm.
m or less, and preferably smaller than the total thickness of the charge transport layer provided below the charge transport layer.

A siloxane-based resin layer having a crosslinked structure is
The charge-transporting layer may also serve as the charge-transporting layer, but is preferably provided on a photosensitive layer such as a charge-transporting layer, a charge-generating layer, or a single-layer-type charge-generating / transporting layer as a separate layer. In this case, it is more preferable to provide an adhesive layer between the photosensitive layer and the resin layer of the present invention.

The material of the conductive support used in the present invention is mainly aluminum, copper, brass, steel,
A belt-shaped or drum-shaped metal material such as stainless steel or another plastic material is used. Among them, aluminum excellent in cost, workability and the like is preferably used, and a thin-walled cylindrical aluminum tube usually formed by extrusion or drawing is often used.

The crosslinkable (also referred to as curable) siloxane resin for forming the siloxane-based resin having a structural unit having a charge transporting property and having a crosslinked structure used in the present invention is prepared by a known method, It is produced using an organosilicon compound having a hydroxyl group or a hydrolyzable group.
The organosilicon compound has a structure of any of the following general formulas (A) to (D).

[0136]

Embedded image

In the formula, R _{1 to} R ₆ represent an organic group in which carbon is directly bonded to silicon in the formula, and Z represents a hydroxyl group or a hydrolyzable group.

When Z in the above formula is a hydrolyzable group, the hydrolyzable group is methoxy, ethoxy, methylethylketoxime, diethylamino, acetoxy, propenoxy, propoxy, butoxy, methoxyethoxy. And the like. Examples of the organic group in which carbon is directly bonded to silicon represented by R _{1 to} R ₆ include alkyl groups such as methyl, ethyl, propyl and butyl, aryl groups such as phenyl, tolyl, naphthyl and biphenyl, and γ.
Epoxy-containing groups such as glycidoxypropyl, β- (3,4-epoxycyclohexyl) ethyl, (meth) acryloyl-containing γ-acryloxypropyl and γ-methacryloxypropyl, γ-hydroxypropyl, 2, 3
-A hydroxyl group such as dihydroxypropyloxypropyl,
Vinyl, vinyl-containing groups such as propenyl, mercapto-containing groups such as γ-mercaptopropyl, γ-aminopropyl, N-
amino-containing groups such as β (aminoethyl) -γ-aminopropyl; halogen-containing groups such as γ-chloropropyl, 1,1,1-trifluoropropyl, nonafluorohexyl, and perfluorooctylethyl; and other nitro and cyano groups Examples include a substituted alkyl group. Further, R _{1 to} R ₆ may have the same or different organic groups.

The organosilicon compound used as a raw material of a curable siloxane resin having a structural unit having charge transporting ability and having a crosslinked structure, which is used in the present invention, is generally substituted with a silicon atom. When the number n of the hydrolyzable groups bonded is 1, the polymerization reaction of the organosilicon compound is suppressed. n is 2, 3 or 4
In the case of (3), the polymerization reaction is likely to occur.
It is possible to advance the crosslinking reaction to a high degree. Therefore, by controlling these, it is possible to control the preservability of the obtained coating layer liquid, the hardness of the coating layer, and the like.

As a raw material of the curable resin, a hydrolysis-condensation product obtained by hydrolyzing the organosilicon compound under acidic or basic conditions to oligomerize or polymerize can be used.

As described above, the curable siloxane resin is an oligomer or polymer having a siloxane bond by previously polymerizing an organosilicon compound. And further, a three-dimensional network structure is formed by polymerization or crosslinking reaction,
A resin that has the ability to cure. That is, it means a siloxane resin formed by promoting a siloxane bond by a hydrolysis reaction and subsequent dehydration condensation of an organosilicon compound having a siloxane bond, and resulting siloxane resin.

Further, the surface layer may be a resin layer in which colloidal silica having a hydroxyl group or a hydrolyzable group is contained in a curable siloxane resin, and silica particles are incorporated in a part of a crosslinked structure.

The definition of the charge transport performance is as follows:
By a known method capable of detecting the charge transporting ability of the me-Of-Flight method, it can be expressed as that a detection current caused by charge transport can be obtained.

In the present invention, the structural unit having a charge transporting property is one in which this partial structure itself has the property of having electron or hole drift mobility (charge transporting ability-imparting group).
It is. The siloxane resin used in the present invention is a resin which has a compound used as a charge transporting substance (hereinafter also referred to as a charge transporting compound or CTM) as a partial structure or can react with this to form a partial structure. .

Examples of the charge transporting compound include hole transporting CTMs: xazole, oxadiazole, thiazole, triazole, imidazole, imidazolone, imidazoline, bisimidazolidin, styryl, hydrazone, benzidine, pyrazoline, stilbene, amine, Oxazolone, benzothiazole, benzimidazole,
Quinazoline, benzofuran, acridine, phenazine,
It has a chemical structure such as aminostilbene, poly-N-vinylcarbazole, poly-1-vinylpyrene, and poly-9-vinylanthracene.

On the other hand, the electron transport type CTM includes succinic anhydride, maleic anhydride, phthalic anhydride, pyromellitic anhydride, melitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, nitrobenzene, dinitrobenzene, trinitrobenzene. , Tetranitrobenzene, nitrobenzonitrile, picryl chloride, quinone chlorimide, chloranil, bromanyl, benzoquinone, naphthoquinone, diphenoquinone, tropoquinone, anthraquinone, 1-chloroanthraquinone, dinitroanthraquinone, 4-nitrobenzophenone, 4,4'-dinitrobenzophenone , 4-nitrobenzalmalonedinitrile, α-cyano-β- (p-cyanophenyl) -2-
(P-chlorophenyl) ethylene, 2,7-dinitrofluorene, 2,4,7-trinitrofluorenone, 2,
4,5,7-tetranitrofluorenone, 9-fluorenylidenedicyanomethylenemalononitrile, polynitro-9-fluoronylidenedicyanomethylenemalonodinitrile, picric acid, o-nitrobenzoic acid, p-nitrobenzoic acid, 3, It has a structure such as 5-dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid, and melitic acid.

Preferred charge-transporting ability-imparting groups include commonly used charge-transporting compounds as described above, and those of compounds having the charge-transporting compound as a partial structure via a carbon atom constituting the charge-transporting compound. It is incorporated into the curable siloxane resin via a connecting atom or a connecting group of Y in the following general formula via a carbon atom, or is incorporated into the curable siloxane resin.

[0148]

Embedded image

X is a charge-transporting ability-imparting group, which is a group bonding to Y in the formula via a carbon atom constituting the imparting group;
Is a divalent or higher valent atom or group excluding adjacent bonding atoms (Si and C). However, when Y is an atom having a valence of 3 or more, the bond of Y other than Si and C in the above formula is bonded to any of the constituent atoms in the curable resin capable of bonding or other atoms. , Having a structure (group) linked to a molecular group.

In the compound represented by the above general formula, an oxygen atom (O), a sulfur atom (S), and a nitrogen atom (N) are particularly preferable as the Y atom. In the case of a nitrogen atom (N), it is NR, and R represents a hydrogen atom or a monovalent organic group.

Although the charge transport-imparting group X is shown as a monovalent group in the above general formula, the charge transport compound to be reacted with the siloxane curable resin has two or more reactive functional groups. In this case, the resin may be joined as a divalent or higher crosslink group in the curable resin, or may be joined simply as a pendant group.

The above-mentioned atoms, that is, the atoms of O, S, and N, are formed by the reaction of a hydroxyl group, a mercapto group, or an amine group and an organic silicon compound having a hydroxyl group or a hydrolyzable group, respectively, introduced into a compound having a charge transporting ability. It is a linking group that is formed and incorporates a charge transport compound into the curable siloxane resin as a partial structure.

Next, the charge transporting compound having a hydroxyl group, a mercapto group and an amine group will be described more specifically.

The charge transporting compound having a hydroxyl group is a charge transporting substance having a commonly used structure and a compound having a hydroxyl group. That is, typically, a charge transporting compound represented by the following general formula that can form a siloxane-based resin layer by bonding with an organosilicon compound can be given, but is not limited to the following structure. Any compound having a charge transporting ability and a hydroxyl group may be used.

X- (R ₇ -OH) _mm ≧ 1 wherein X is a charge-transporting group, R _{7 is a} bond, each substituted or unsubstituted alkylene or arylene group, and m is 1 to 5 It is an integer.

Among them, the following are typical ones. For example, a triarylamine-based compound has a triarylamine structure such as triphenylamine as a charge transporting ability-imparting group (X), and has an alkylene or arylene group extended from a carbon atom constituting X or extended from X. Is a compound having a hydroxyl group.

In the present invention, an electrostatic latent image formed by performing charging and image exposure on a photoreceptor is developed with a developer, and a toner image formed is transferred to a transfer material using a contact transfer method. The fixing and cleaning steps are repeated to form a large number of images.

(Transfer Roll) The transfer of the toner image from the photoreceptor surface to the transfer material is performed by elastically pressing the transfer roll against the photoreceptor and applying a bias voltage to the toner image. As the transfer roll, an elastic body made of rubber, a porous foam, or the like is used. For example, (1) an ion conductive type manufactured by Bridgestone, (2) an electronic conductive type manufactured by Bridgestone, (3) a urethane foamed ruby cell type manufactured by Toyo Polymer, (4) an ion conductive type manufactured by Sumitomo Rubber Industries, and (5) Sumitomo. EPDM type manufactured by Rubber Industries,
(6) Epichlorohydrin type manufactured by Sumitomo Rubber Industries, Ltd.
(7) ENDUR ion conductive type manufactured by Inoac Corporation, (8) foamed silicone type manufactured by Tigers Polymer, (9) urethane foamed type manufactured by Hokushin Kogyo, (10) foamed silicone type manufactured by Shin-Etsu Polymer, or (11) Nitto Kogyo Various types of transfer rolls, such as a carbon black-containing ruby cell foam type manufactured by Kuraray Co., Ltd., may be mentioned, but a foam type is preferred.

In the image forming method used in the present invention, in order to transfer the toner image on the surface of the photoreceptor to the transfer material satisfactorily, the pressing force of the transfer roll against the photoreceptor is 2.5 to 10
0 kPa is preferable and 10-80 kPa is more preferable.

When the pressing force is 2.5 to 100 kPa, the transfer of the toner image becomes sufficient, and the release agent in the toner can be prevented from being transferred to the surface of the photosensitive member, and the occurrence of image defects can be prevented. I can do it. In addition, the impact when the transfer roll is released is reduced, preventing image defects due to transfer deviation,
Damage to the photoreceptor can be prevented.

As the characteristics required for the transfer roll, for example, the rebound resilience, electric resistance, surface hardness and the like are important.

The resilience of the elastic body of the transfer roll is preferably 30 to 70%. When the rebound resilience is 30 to 70%, a sufficient pressing force to the photoreceptor for transferring the toner image can be obtained, so that a good transfer rate can be obtained and the impact at the time of transfer can be reduced. Can be prevented from occurring. The rebound resilience is JIS
It is measured by the measuring method of K7311.

The transfer roll needs to have an appropriate conductivity in order to enable application of a bias voltage for transferring a toner image, and has an electric resistance of 1 × 1 measured by the following measuring method.
It is preferably from 0 ³ to 1 × 10 ¹³ Ω.

Measurement method: 4 m thick on a rotating shaft having a diameter of 16 mm and a length of 310 mm
transfer roller provided with an elastic body having a thickness of 20 m is pressed against an aluminum tube having a diameter of 30 mm with a force of 17 kPa.
Under an environment of 0% RH, the electric resistance value between the rotation axis of the transfer roll and the aluminum tube is measured.

The surface hardness of the elastic body measured by an Asker C hardness tester is preferably 20 to 70 degrees. Asker C hardness 2
A transfer roll made of an elastic material having a hardness of 0 to 70 degrees is preferable because transfer is properly performed and image defects such as transfer deviation do not occur.

The image forming apparatus used in the image forming method for forming a large number of images of the present invention will be described with reference to the drawings.

Incidentally, the image forming method of the present invention for forming a large number of images refers to a method in which an electrostatic latent image formed by performing charging and image exposure on a photosensitive member contains a toner for developing an electrostatic latent image. An image forming method for forming a large number of images by transferring a toner image formed by developing with a developer onto a transfer material by using a contact transfer method, and thereafter repeating each process of separating, fixing and cleaning. say.

FIG. 12 is a schematic diagram showing an example of an image forming apparatus using a transfer roll. In FIG. 12, a photoreceptor 10 is an organic photoreceptor that rotates in the direction of an arrow, and 11 is a charger for uniformly charging the photoreceptor. The charger is a corona discharger, a roller charger, a magnetic charger. It may be a brush charger. Reference numeral 12 denotes analog image exposure light or digital image exposure light using a semiconductor laser, a light emitting diode, or the like, and an electrostatic latent image is formed on the photoconductor by the image exposure light. This electrostatic latent image is developed in a contact or non-contact manner by a developing device 13 containing a developer containing a fine particle toner having a volume average particle size of 2.2 to 9 μm, and a toner image is formed on the photoconductor. .

The toner image is transferred onto the transfer material P conveyed in a timely manner by the transfer roll 15 at a pressing force of 2.5 to 100 kPa, preferably 10 to 80 kPa on the photosensitive member under the application of a DC bias.

The DC bias power supply 16 for applying a bias to the transfer roll 15 is preferably a constant current power supply or a constant voltage power supply. In the case of the constant current power supply, 5 to 15 μA
In the case of a constant voltage power supply, the absolute value is 400 to 1500.
V.

The transfer material P on which the image has been transferred by the transfer roll 15 is separated from the photoreceptor 10 by the separation pole 14 and conveyed to a fixing device (not shown) to be heated and fixed.

The surface of the photoreceptor after the transfer is cleaned by a cleaning blade 17 and then discharged by a discharge lamp (PCL) 18 to prepare for the next image formation. Reference numeral 19 denotes a paper feed roller, and reference numeral 20 denotes a fixing device.

(Intermediate Transfer Body) The transfer of a toner image from a photoreceptor to a transfer material can also be performed by a method using an intermediate transfer body. That is, an image forming unit (image forming unit) is provided for each of the four color developers, and in each image forming unit, a visible image of each color is formed on each photoconductor, and these visible images are sequentially transferred to an intermediate transfer member. It can also be preferably used in a system in which a color image is obtained by transferring and collectively transferring to a transfer material (usually plain paper, but is not particularly limited as long as it can be transferred) and then fixing it.

An image forming method in which images of a plurality of colors are formed in an image forming section, and the images are successively superimposed and transferred on the same intermediate transfer member will be described with reference to the drawings.

FIG. 13 is a schematic diagram showing an example of an image forming apparatus using an intermediate transfer member (transfer belt).

Referring to FIG. 13, the image forming apparatus for obtaining a color image includes a plurality of image forming units, each of which forms a visible image (toner image) having a different color from each other. This is an image forming method in which images are sequentially superimposed and transferred on the same intermediate transfer member.

Here, first, second, third and fourth image forming units Pa, Pb, Pc and Pd are arranged side by side, and the image forming sections are each a photosensitive element which is an electrostatic latent image forming body. It has bodies 1a, 1b, 1c and 1d.

The photosensitive members 1a, 1b, 1c and 1d have latent image forming portions 2a, 2b, 2c and 2d and a developing portion 3
a, 3b, 3c and 3d, transfer discharge parts 4a, 4b, 4c
And 4d, cleaning devices 5a, 5b, 5c and 5d having a cleaning member and a rubber blade, a charging device 6
a, 6b, 6c and 6d are arranged.

With such a configuration, first, a latent image of, for example, a yellow component color in a document image is formed on the photoreceptor 1a of the first image forming unit Pa by the latent image forming section 2a. The latent image is converted into a visible image by the developer containing the yellow toner in the developing unit 3a, and is transferred to the transfer belt 21 by the transfer discharging unit 4a.

On the other hand, while the yellow toner image is being transferred to the transfer belt 21 as described above, a magenta component color latent image is formed on the photoreceptor 1b in the second image forming unit Pb. At 3b, a visible image is formed with a developer containing a magenta toner. This visible image (magenta toner image) is transferred onto the transfer belt 21 at a predetermined position when the transfer belt, which has been transferred by the first image forming unit Pa, is carried into the transfer discharge unit 4b. You.

Hereinafter, the third and fourth steps are performed in the same manner as described above.
Cyan component color by the image forming units Pc and Pd of
An image of a black component color is formed, and a cyan toner image and a black toner image are transferred on the same transfer belt in a superimposed manner. When such an image forming process is completed, a multicolor superimposed image is obtained on the transfer belt 21. On the other hand, each of the photoconductors 1a, 1b,
And 1d, the residual toner is removed by the cleaning devices 5a, 5b, 5c and 5d, and is used for the subsequent latent image formation.

In the image forming apparatus, the transfer belt 2
13, the transfer belt 21 is used in FIG.
Is transported from the right side to the left side, passes through the transfer discharge sections 4a, 4b, 4c and 4d in the image forming units Pa, Pb, Pc and Pd in the course of the transport, and the color transfer images are transferred.

When the transfer belt 21 is in the fourth image forming unit P
When the voltage passes d, the AC voltage is applied to the separation / discharge discharger 22d, the transfer belt 21 is discharged, and the toner image is collectively transferred onto the transfer material P. Thereafter, the transfer material P enters the fixing device 23, is fixed, and is discharged from the discharge port 25.

Incidentally, in the drawing, 22a, 22b, 22c and 2
2d is a separation static elimination discharger. After the transfer of the toner image, the transfer belt 21 is cleaned of residual toner by a cleaning device 24 using both a brush-like cleaning member and a rubber blade, and is ready for the next image formation.

As described above, the multi-color superimposed image is formed on the long transfer belt 21 such as the transport belt, and the multi-color superimposed image is collectively transferred to the transfer material. The units may be provided with independent transfer belts, and then the transfer material may be sequentially transferred from each transfer belt to the transfer material.

The transfer belt is preferably made of, for example, a polyimide, polyether, polyamide or tetrafluoroethylene / perfluorovinyl ether copolymer having a surface resistance of at least 10 ¹⁴ Ω and a high-resistance film having a thickness of about 20 μm. And a conductive agent is added to a fluorine-based or silicon-based resin to make the surface resistance 10 ⁵ to 10 ⁸ Ω.
An endless film provided with a m-thick release layer is used.

[0187]

EXAMPLES The present invention will be described specifically with reference to Examples.
The scope of the present invention is not limited to this.

<Preparation of Toner> (Preparation of Toner 1: Emulsion Polymerization Association Method) In a 20 L container, 0.90 kg of sodium n-dodecyl sulfate and 10.0 L of pure water were put and dissolved by stirring. To this solution, 1.20 kg of Regal 330R (carbon black manufactured by Cabot Corporation) was gradually added, and the mixture was stirred well for 1 hour, and then continuously dispersed for 20 hours using a sand grinder (medium type disperser). This dispersion was referred to as “colorant dispersion 1”. In addition, a solution composed of 0.055 kg of sodium dodecylbenzenesulfonate and 4.0 L of ion-exchanged water was referred to as “anionic surfactant solution A”.

0.014 kg of a 10 mol adduct of nonylphenol polyethylene oxide and 4.0 L of ion-exchanged water
Is referred to as "nonionic surfactant solution B".
223.8 g of potassium persulfate was added to 12.0 L of deionized water.
Was dissolved in "initiator solution C".

A wax emulsion (polypropylene emulsion having a number average molecular weight of 3000: a number average primary particle diameter of 120 nm, a solid concentration of 29.9) was placed in a 100 L GL (glass lining) reactor equipped with a temperature sensor, a cooling pipe, and a nitrogen introducing device. Mass%) 3.41 kg, the total amount of “anionic surfactant solution A” and “nonionic surfactant solution B”
The whole amount was added and stirring was started. The configuration of the stirring blade was the configuration shown in FIG. Next, 44.0 L of ion-exchanged water was added. Next, heating was started, and when the liquid temperature reached 75 ° C., the entire amount of “initiator solution C” was added dropwise. Then, while controlling the liquid temperature to 75 ° C. ± 1 ° C., the styrene 1
2.1 kg, 2.88 kg of n-butyl acrylate, 1.04 kg of methacrylic acid and t-dodecyl mercaptan 5
A solution obtained by previously mixing 48 g was dropped. After the completion of the dropwise addition, the temperature of the solution was raised to 80 ° C. ± 1 ° C., and the mixture was heated and stirred for 6 hours. Next, the liquid temperature was cooled to 40 ° C. or lower, stirring was stopped, and the mixture was filtered with a pole filter, and the filtrate was designated as “latex A”.

The glass transition temperature of the resin particles in “Latex A” was 57 ° C., the softening point was 121 ° C., the weight average molecular weight was 127,000, and the weight average particle size was 120 nm.

A solution prepared by dissolving 0.055 kg of sodium dodecylbenzenesulfonate in 4.0 L of ion-exchanged pure water was designated as “anionic surfactant solution D”. A solution obtained by dissolving 0.014 kg of a nonylphenol polyethylene oxide 10 mol adduct in 4.0 L of ion-exchanged water was referred to as "nonionic surfactant solution E".

Potassium persulfate (Kanto Chemical) 200.
A solution in which 7 g was dissolved in 12.0 L of ion-exchanged water was referred to as “initiator solution F”.

A 100 L GL reactor equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a comb-shaped baffle (the structure of the stirring blade is shown in FIG. 10) was charged with a wax emulsion (polypropylene emulsion having a number average molecular weight of 3000: number average primary particle diameter). (120 nm, solid content concentration: 29.9% by mass) 3.41
kg, the whole amount of “anionic surfactant solution D” and the whole amount of “nonionic surfactant solution E” were added, and stirring was started. Next, 44.0 L of ion-exchanged water was charged. Next, heating was started, and when the liquid temperature reached 70 ° C., “Initiator solution F” was added. Then, 11.0 kg of styrene,
4.00 kg of n-butyl acrylate, methacrylic acid 1.
A solution previously mixed with 04 kg and 9.02 g of t-dodecyl mercaptan was added dropwise. After completion of the dropwise addition, the mixture was heated and stirred for 6 hours while controlling the liquid temperature at 72 ° C. ± 2 ° C.
Next, the liquid temperature was raised to 80 ° C. ± 2 ° C., and the mixture was heated and stirred for 12 hours. Next, the liquid temperature was cooled to 40 ° C. or less, and stirring was stopped. The solution was filtered through a pole filter, and the filtrate was designated as "latex B".

The glass transition temperature of the resin particles in “Latex B” was 58 ° C., the softening point was 132 ° C., the weight average molecular weight was 245,000, and the weight average particle size was 110 nm.

Sodium chloride 5.36k as salting-out agent
g was dissolved in 20.0 L of ion-exchanged water to obtain "sodium chloride solution G".

A solution obtained by dissolving 1.00 g of a fluorinated nonionic surfactant in 1.00 L of ion-exchanged water was designated as “nonionic surfactant solution H”.

A 100 L SU equipped with a temperature sensor, a cooling pipe, a nitrogen introduction device, and a particle size and shape monitoring device.
In the S reaction vessel (the configuration of the stirring blade is shown in FIG. 10), 20.0 kg of the “latex A” and “latex B” 5.
2 kg, 0.4 kg of “colorant dispersion 1”, and 20.0 kg of ion-exchanged water were added and stirred. Next, the mixture was heated to 40 ° C., and “Sodium chloride solution G”, 6.00 kg of isopropanol (manufactured by Kanto Kagaku), and “Nonionic surfactant solution H” were added in this order. Thereafter, after standing for 10 minutes, the temperature was raised, the temperature of the solution was raised to 85 ° C. over 60 minutes, and the mixture was heated and stirred at 85 ± 2 ° C. for 0.5 to 3 hours while salting out / fusing. The grain size was grown. Next, 2.1L of pure water
Was added to stop the growth of the particle size, thereby producing a "fused particle dispersion".

The “fused particle dispersion” prepared above was placed in a 5 L reaction vessel equipped with a temperature sensor, a cooling pipe, and a particle size and shape monitoring device (the structure of the stirring blade is shown in FIG. 7).
Then, the mixture was heated and stirred at a liquid temperature of 85 ° C. ± 2 ° C. for 0.5 to 15 hours to control the shape. Thereafter, the mixture was cooled to 40 ° C. or lower and the stirring was stopped. Next, classification was performed in the liquid by centrifugal sedimentation using a centrifugal separator, followed by filtration with a sieve having openings of 45 μm, and this filtrate was used as “association liquid”. Next, the wet cake-like “non-spherical particles” were filtered from the association liquid using a Nutsche. Then, it was washed with ion-exchanged water.

The “non-spherical particles” were dried at a suction temperature of 60 ° C. using a flash jet drier, and further dried at a temperature of 60 ° C. using a fluidized bed drier to produce “colored particles”. 1 of the "colored particles" obtained
1 part by mass of silica fine particles was externally added and mixed with 00 parts by mass with a Henschel mixer, and “toner” was obtained by an emulsion polymerization association method.
Was prepared.

In the monitoring of the salting-out / fusion step and the shape control step, the number of rotations of the stirring and the heating time are controlled to control the variation coefficient of the shape and the shape coefficient.
Furthermore, the “toner 1 to 50” shown in Tables 1 and 2 were prepared by arbitrarily adjusting the variation coefficient of the shape coefficient, the number variation coefficient in the number particle size distribution, and the agglomeration rate by submerged classification.

[0202]

[Table 1]

[0203]

[Table 2]

(Toner Preparation 2: Emulsion Polymerization Association Method) In Toner Preparation 1, except that 1.05 kg of a benzidine-based yellow pigment was used instead of carbon black as the colorant, 51 to 59 ".

(Toner Production 3: Emulsion Polymerization Association Method) In toner production 1, except that 1.20 kg of a quinacridone-based magenta pigment was used in place of carbon black as a coloring agent, the same procedure as shown in Table 3 was carried out. 60 to 68 ".

(Toner Preparation 4: Emulsion Polymerization Association Method) Toner 69 shown in Table 3 was prepared in the same manner as in toner preparation 1, except that 0.60 kg of a phthalocyanine cyan pigment was used instead of carbon black as a coloring agent. ~ 77 were produced.

[0207]

[Table 3]

(Toner Production 5: Suspension Polymerization Method) In a 2 L container, 165 g of styrene, 35 g of n-butyl acrylate, 10 g of carbon black, 2 g of a metal compound of di-tert-butylsalicylate, 8 g of a styrene-methacrylic acid copolymer and 8 g of paraffin wax (Mp = 70 ° C.)
Heated to 0 ° C, TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.)
At 12000 rpm to uniformly disperse and disperse. To this, 10 g of 2,2'-azobis (2,4-valeronitrile) as a polymerization initiator was added and dissolved to prepare a "polymerizable monomer composition". Then, add 0.10 g to 710 g of ion exchanged water.
450 g of a 1 M aqueous sodium phosphate solution was added, and 68 g of 1.0 M calcium chloride was gradually added while stirring at 13,000 rpm with a TK homomixer to prepare a “suspension” in which tricalcium phosphate was dispersed. The “polymerizable monomer composition” was added to the “suspension”, and the mixture was stirred at 10,000 rpm for 20 minutes with a TK homomixer to “granulate” the polymerizable monomer composition. Then, the configuration of the stirring blade was changed as shown in FIG.
Using the reactor as described in (b) above,
The reaction was performed for 15 hours. Tricalcium phosphate was dissolved and removed with hydrochloric acid, and then classified in a liquid by a centrifugal sedimentation method using a centrifugal separator, followed by filtration, washing and drying to prepare “colored particles”. To 100 parts by mass of the obtained “colored particles”, 1 part by mass of silica fine particles was externally added and mixed with a Henschel mixer to prepare a “toner” by a suspension polymerization method.

By monitoring at the time of the polymerization and controlling the liquid temperature, the number of rotations of the stirring, and the heating time,
The shape coefficient and the coefficient of variation of the shape coefficient were controlled, and the coefficient of variation of the shape coefficient, the number coefficient of variation in the number particle size distribution, and the aggregation rate were arbitrarily adjusted by submergence classification. Was prepared.

[0210]

[Table 4]

(Toner Production 6: Suspension Polymerization Method) In toner production 5, except that the structure of the stirring blade was as shown in FIG. 7 and classification was not performed in a liquid using a centrifuge, the same as above. Thus, “Toner 84” shown in Table 4 was produced.

<Preparation of Photoreceptor> (Preparation of Photoreceptor 1) << Undercoat Layer >> Titanium chelate compound (TC-750, manufactured by Matsumoto Pharmaceutical Co., Ltd.) 30 g Silane coupling agent (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) ) 17 g of 2-propanol (150 mL) was mixed and dissolved to prepare an “undercoat layer coating solution”. Using this coating solution, a dip coating method is applied to a cylindrical aluminum support having a diameter of 60 mm to form a “undercoat layer” having a thickness of 0.5 μm.
Was formed.

<< Charge Generating Layer >> Y-type titanyl phthalocyanine 60 g, silicone-modified butyral resin 700 g (X-40-1211M, manufactured by Shin-Etsu Chemical Co., Ltd.) t-butanol 1600 mL 2-methoxymethylpentanone 400 mL were mixed, and the mixture was mixed with a sand mill. The mixture was dispersed for 10 hours to prepare a “charge generation layer coating liquid”. This coating solution was applied on the “undercoat layer” by a dip coating method to form a “charge generation layer” having a thickness of 0.2 μm.

<< Charge Transport Layer >> Charge transport substance (N- (4-methylphenyl) -N- (4-β-225 g phenylstyrylphenyl) -p-toluidine) Bisphenol Z-type polycarbonate 300 g (average molecular weight 50,000) Antioxidant (Compound 1) 6g Dichloromethane 2000mL

[0215]

Embedded image

Are mixed and dissolved to form a “charge transport layer coating solution”
Was prepared. This coating solution was applied on the “charge generation layer” by dip coating, and then dried at 100 ° C. for 60 minutes to form a “charge transport layer” having a thickness of 25 μm, thereby producing “Photoconductor 1”. .

(Preparation of Photoreceptor 2) Like the photoreceptor 1, up to the “charge generation layer” was formed.

<< Charge Transport Layer >> Charge transport substance (N- (4-methylphenyl) -N- (4-β-225 g tolystyrylphenyl) -p-anisidine) Bisphenol Z-type polycarbonate 300 g (average molecular weight 30,000) 6 g of an antioxidant (compound 1) and 2,000 mL of dichloromethane 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, and then dried at 100 ° C. for 60 minutes to form a film having a thickness of 25 μm.
m of the “charge transport layer” was formed to prepare “Photoconductor 2”.

(Preparation of Photoreceptor 3) The “charge transport layer coating solution” of the photoreceptor 1 was applied on the “charge generation layer” of the photoreceptor 1 by a dip coating method, followed by drying at 100 ° C. for 60 minutes. Film thickness 2
A 3 μm “charge transport layer” was formed.

<< Surface Protective Layer >> Methylmethoxysilane 182 g Charge-transporting substance (compound 2) 40 g Antioxidant (compound 3) 1 g 2-propanol 225 g 2% acetic acid 106 g colloidal silica 106 g dibutyltin acetate 1 g

[0221]

Embedded image

Were mixed to prepare a "coating solution for surface protective layer". After forming a layer having a thickness of 2 μm on the charge transporting layer by using a circular amount controlling coating apparatus, the coating liquid is cured by heating at 100 ° C. for 60 minutes to form a “siloxane-based surface protective layer” having a crosslinked structure. Then, "Photoconductor 3" was produced.

<Transfer Roll> The following "transfer rolls 1 and 2" were used as the transfer rolls.

[0224] The voltage applied to the transfer rolls 1 and 2 was -1000V.

<Transfer Belt> The following "transfer belt" was used as the transfer belt.

“Transfer belt” is a polyimide film
(Surface resistance 10¹⁴Ω, 20μm thick high resistance film)
And a conductive agent is added to the fluororesin to reduce the surface resistance to 7
× 10 ⁶A release layer with a thickness of 10 μm is provided as Ω.
Endless film.

<Preparation of Developer> Each of “Toners 1 to 84” and a 65 μm “ferrite carrier” coated with a silicone resin were mixed at a ratio of toner / carrier = 50 g / 950 g, and “Development” for evaluation was evaluated. Agents 1 to 84 "were produced.

<Evaluation> Evaluation using a high-speed printer using a transfer roll
os 7075 "(printing speed: 75 sheets / min).

(Evaluation Method) The above-mentioned “Toners 1 to 50, 78”
-84 "and" Developers 1-50, 78-84 ", and the B4 plate original image (10% coverage image) having solid black, halftone, characters, and a blank portion is applied to the printer by the" photoconductor ". 1 to 3 "and the above-mentioned" transfer rolls 1 and 2 "were continuously printed, and the evaluation of the" transfer rate "," the occurrence of voids "and" the occurrence of toner filming "of the 1 millionth sheet was evaluated. went. The toner collected from the cleaning unit was not returned to the developing device but was taken in a bag.

(Evaluation Results) "Transfer Rate" The transfer rate (%) was determined by the following equation (6).

Formula (6) Transfer rate (%) = {1− (mass of collected toner / mass of consumed toner)} × 100 “Occurrence of void” The presence or absence of the occurrence of void in the character was visually observed. .

Evaluation criteria were as follows: No hollow area occurred. ○ A hollow area occurred. × “Toner filming”. The presence or absence of toner filming on the photoreceptor surface was visually observed.

The evaluation criteria are as follows: No toner filming occurred. ○ Toner filming occurred. × Evaluation results are shown in Tables 5 and 6.

[0234]

[Table 5]

[0235]

[Table 6]

[0236] 2. Evaluation with a color printer using a transfer belt The “toner 60 to 77” and the “developer 60 to 77”
The B4 plate original image (10% coverage image) having solid black, halftones, characters, and a blank portion was applied to the “photoconductor 3” in the “image forming apparatus using a transfer belt” shown in FIG. Attach the `` transfer belt '', copy continuously,
The "transfer rate", "occurrence of voids" and "occurrence of toner filming" of the 500,000th sheet were evaluated. The toner collected from the cleaning unit was not returned to the developing device but was taken in a bag.

(Evaluation Results) "Transfer Rate" The transfer rate (%) was determined by the above equation (6).

"Occurrence of a void" The presence or absence of the occurrence of a void in a character portion was visually observed.

Evaluation criteria were as follows: no hollowing occurred. ○ hollowing occurred. × “Toner filming”. The presence or absence of toner filming on the photoreceptor surface was visually observed.

Evaluation criteria are as follows: No toner filming occurred. ○ Toner filming occurred. × Evaluation results are shown in Table 7.

[0241]

[Table 7]

[0242]

As has been demonstrated in the examples, the present invention has been proposed in view of the above problems, and has as its object the purpose of the present invention is to provide a contact transfer type image having a defect in an image, a reduction in the transfer rate, and a reduction in the transfer rate. It is possible to provide a toner, an image forming method, and an image forming apparatus that do not cause the problem of toner filming to the toner.

[Brief description of the drawings]

FIG. 1 is an example of a void.

FIG. 2 is a model diagram of toner having no corners and toner having corners.

FIG. 3 is a schematic view showing an example of a stirring tank provided with a stirring blade which has been conventionally used.

FIG. 4 is a schematic diagram showing an example of a stirring tank provided with a more preferable stirring blade.

FIG. 5 is a top sectional view of FIG. 4;

FIG. 6 is a schematic diagram of a shape of a stirring blade.

FIG. 7 is a schematic diagram of a stirring tank having a slit in a lower stirring blade and a bent and projected end.

FIG. 8 is a schematic view of a stirring tank having a projection at an end of a stirring blade and / or a bent portion at the end.

FIG. 9 is a schematic diagram of a stirring tank having three stages of stirring blades.

FIG. 10 is a schematic diagram of a stirring tank having a gap in an upper stirring blade and having a bent portion and a projection at an end of the lower stirring blade.

FIG. 11 is a schematic view of a stirring tank having a protrusion at an end of an upper stirring blade and a bend at an end of a lower stirring blade.

FIG. 12 is a schematic configuration diagram illustrating an example of an image forming apparatus using a transfer roll.

FIG. 13 is a schematic configuration diagram illustrating an example of an image forming apparatus using a transfer belt.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat exchange jacket 2 Stirring tank 3 Rotating shaft 4 Lower stirring blade 5 Upper stirring blade 6 Medium hole 10 Photoconductor 11 Charger 12 Image exposure light 13 Developing device 14 Separation electrode 15 Transfer roll 16 Bias power supply 17 Cleaning Blade 18 Static elimination lamp 19 Paper feed roller 20 Fixing device P Transfer material Pa, Pb, Pc, Pd Image forming unit 1a, 1b, 1c, 1d Photoconductor 2a, 2b, 2c, 2d Latent image forming unit 3a, 3b, 3c, 3d developing unit 4a, 4b, 4c, 4d transfer discharging unit 5a, 5b, 5c, 5d cleaning unit 6a, 6b, 6c, 6d charging unit 21 transfer belt 22a, 22b, 22c, 22d separation discharging unit 23 fixing device 24 cleaning Vessel 25 outlet

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 9/09 G03G 9/08 361 381 (72) Inventor Hiroshi Yamazaki 2970 Ishikawacho, Hachioji-shi, Tokyo Konica shares In-house F term (reference) 2H005 AA15 AA21 AB03 AB06 EA05 2H068 BA58 BB25 BB33 BB44 BB52 BB57 FA04 FB13 FC11

Claims (51)

[Claims] 1. A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photosensitive member with a developer containing a toner for developing an electrostatic latent image, and contact-transferring the toner image. In the image forming method for forming a large number of images by repeating the steps of transferring to a transfer material using a method and then performing separation, fixing and cleaning, the toner for developing an electrostatic latent image An image forming method, wherein the coefficient of variation of the coefficient is 16% or less, the number variation coefficient in the number particle size distribution is 27% or less, and the toner aggregation rate is 3 to 35%. 2. The image forming apparatus according to claim 1, wherein the toner for developing an electrostatic latent image contains 65% by number or more of toner particles having a shape coefficient in a range of 1.0 to 1.6. Method. 3. The image forming apparatus according to claim 1, wherein the toner for developing an electrostatic latent image has 65% by number or more of toner particles having a shape coefficient in a range of 1.2 to 1.6. Method. 4. The image forming method according to claim 1, wherein the toner for developing an electrostatic latent image has a ratio of toner particles having no corners of 50% by number or more. 5. The image forming method according to claim 1, wherein the toner for developing an electrostatic latent image has a number average particle size of 2.2 to 9 μm. 6. The particle diameter of the toner for developing an electrostatic latent image is D
(Μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23. Relative frequency of toner particles for latent image development (m1)
The sum (M) of the relative frequency (m2) of the particles of the toner for developing an electrostatic latent image included in the class having the second highest frequency after the mode is 70% or more. 1 to
6. The image forming method according to any one of 5. 7. The image forming method according to claim 1, wherein the toner for developing an electrostatic latent image is obtained by polymerizing a polymerizable monomer in an aqueous medium. 8. The toner for developing an electrostatic latent image according to claim 1, wherein the toner is obtained by associating resin particles in an aqueous medium.
The image forming method according to any one of claims 1 to 7, wherein 9. A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photosensitive member with a developer containing a toner for developing an electrostatic latent image, and transferring the toner image by contact transfer. In the image forming method for forming a large number of images by repeating the steps of transferring to a transfer material using a method and then performing separation, fixing and cleaning, the toner for developing an electrostatic latent image An image forming method, wherein the ratio of toner particles having no toner is 50% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the toner aggregation rate is 3 to 35%. 10. The image forming apparatus according to claim 9, wherein the toner for developing an electrostatic latent image has 65% by number or more of toner particles having a shape factor in a range of 1.0 to 1.6. Method. 11. The image forming apparatus according to claim 9, wherein the toner for developing an electrostatic latent image has 65% by number or more of toner particles having a shape coefficient in a range of 1.2 to 1.6. Method. 12. The toner according to claim 9, wherein the toner for developing an electrostatic latent image has a number average particle size of 2.2 to 9 μm.
2. The image forming method according to claim 1. 13. When the particle diameter of the toner for developing an electrostatic latent image is D (μm), the natural logarithm lnD is plotted on the horizontal axis.
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 (m1) of the toner particles for electrostatic latent image development included in the most frequent class
The sum (M) of the relative frequency (m2) of the toner particles for electrostatic latent image development included in the class having the second highest frequency after the mode is 70% or more. 9 ~
13. The image forming method according to any one of the above items 12. 14. The image forming method according to claim 9, wherein the toner for an electrostatic latent image is obtained by polymerizing a polymerizable monomer in an aqueous medium. 15. The electrostatic latent image toner is obtained by associating resin particles in an aqueous medium.
15. The image forming method according to any one of 14. 16. A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photosensitive member with a developer containing a toner for developing an electrostatic latent image, and contact-transferring the toner image. In the image forming method for forming a large number of images by repeating the steps of transferring to a transfer material using a method and then performing separation, fixing and cleaning, the toner for developing an electrostatic latent image 65% by number or more of toner particles having a coefficient in the range of 1.2 to 1.6, and a variation coefficient of the shape coefficient is 1
An image forming method, wherein the toner aggregation rate is 6% or less and the toner aggregation rate is 3 to 35%. 17. The image forming method according to claim 16, wherein in the toner for developing an electrostatic latent image, a ratio of toner particles having no corners is 50% by number or more. 18. The image forming method according to claim 16, wherein the number average particle diameter of the electrostatic latent image developing toner is 2.2 to 9 μm. 19. When the particle diameter of toner particles for electrostatic latent image development is D (μm), the natural logarithm lnD is plotted on the horizontal axis,
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 (m1) of the toner particles for electrostatic latent image development included in the most frequent class
The sum (M) of the relative frequency (m2) of the toner particles for electrostatic latent image development included in the class having the second highest frequency after the mode is 70% or more. 16
19. The image forming method according to any one of claims 18 to 18. 20. The image forming method according to claim 16, wherein the toner for developing an electrostatic latent image is obtained by polymerizing a polymerizable monomer in an aqueous medium. 21. The image forming method according to claim 16, wherein the toner for developing an electrostatic latent image is obtained by associating resin particles in an aqueous medium. 22. An image forming method comprising the steps of cleaning, forming an electrostatic latent image, developing, transferring and fixing using the image forming method according to any one of claims 1, 9 and 16. apparatus. 23. A color toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photoreceptor with a developer containing a toner for developing an electrostatic latent image. An image forming method for forming a large number of images by repeating the steps of transferring from an intermediate transfer body to a transfer material using a contact transfer method, and then separating, fixing and cleaning, after the transfer is performed on the transfer body. Wherein the electrostatic latent image developing toner has a shape coefficient variation coefficient of 16% or less, a number variation coefficient in a number particle size distribution of 27% or less, and a toner aggregation rate of 3 to 35%. Image forming method. 24. The image forming apparatus according to claim 23, wherein the toner for developing an electrostatic latent image has 65% by number or more of toner particles having a shape factor in a range of 1.0 to 1.6. Method. 25. The image forming apparatus according to claim 23, wherein the toner for developing an electrostatic latent image contains 65% by number or more of toner particles having a shape factor in a range of 1.2 to 1.6. Method. 26. The image forming method according to claim 23, wherein the toner for developing an electrostatic latent image has a ratio of toner particles having no corners of 50% by number or more. 27. The electrostatic latent image developing toner according to claim 23, wherein the number average particle diameter is 2.2 to 9 μm.
The image forming method according to any one of items 26 to 26. 28. When the particle diameter of the toner for developing an electrostatic latent image is D (μm), the natural logarithm lnD is plotted on the horizontal axis.
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 (m1) of the toner particles for electrostatic latent image development included in the most frequent class
The sum (M) of the relative frequency (m2) of the toner particles for electrostatic latent image development included in the class having the second highest frequency after the mode is 70% or more. 23
28. The image forming method according to any one of items 27 to 27. 29. The image forming method according to claim 23, wherein the electrostatic latent image developing toner is obtained by polymerizing a polymerizable monomer in an aqueous medium. 30. The image forming method according to claim 23, wherein the toner for developing an electrostatic latent image is obtained by associating resin particles in an aqueous medium. 31. A color toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photoreceptor with a developer containing a toner for developing an electrostatic latent image, to form an intermediate image. An image forming method for forming a large number of images by repeating the steps of transferring from an intermediate transfer body to a transfer material using a contact transfer method, and then separating, fixing and cleaning, after the transfer is performed on the transfer body. In the toner for developing an electrostatic latent image, the ratio of the toner particles having no corners is 50% by number.
As described above, the image forming method is characterized in that the number variation coefficient in the number particle size distribution is 27% or less and the toner aggregation rate is 3 to 35%. 32. The image forming apparatus according to claim 31, wherein the toner for developing an electrostatic latent image has 65% by number or more of toner particles having a shape factor in a range of 1.0 to 1.6. Method. 33. The image forming apparatus according to claim 31, wherein the toner for developing an electrostatic latent image has 65% by number or more of toner particles having a shape coefficient in a range of 1.2 to 1.6. Method. 34. The electrostatic latent image developing toner according to claim 31, wherein the toner has a number average particle size of 2.2 to 9 μm.
34. The image forming method according to any one of items 33. 35. When the particle diameter of the electrostatic latent image developing toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis,
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 (m1) of the toner particles for electrostatic latent image development included in the most frequent class
The sum (M) of the relative frequency (m2) of the toner particles for electrostatic latent image development included in the class having the second highest frequency after the mode is 70% or more. 31
35. The image forming method according to any one of items 34 to 34. 36. The image forming method according to claim 31, wherein the toner for developing an electrostatic latent image is obtained by polymerizing a polymerizable monomer in an aqueous medium. 37. The toner for developing an electrostatic latent image according to claim 31, wherein the resin particles are associated with each other in an aqueous medium.
37. The image forming method according to any one of Items 36 to 36. 38. A color toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photosensitive member by using a developer containing a toner for developing an electrostatic latent image, An image forming method for forming a large number of images by repeating the steps of transferring from an intermediate transfer body to a transfer material using a contact transfer method, and then separating, fixing and cleaning, after the transfer is performed on the transfer body. In the toner for developing an electrostatic latent image, the number of toner particles having a shape coefficient in the range of 1.2 to 1.6 is 65% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the toner aggregates. Rate is 3-35%
An image forming method, characterized in that: 39. The image forming method according to claim 38, wherein the toner for developing an electrostatic latent image has a ratio of toner particles having no corners of 50% by number or more. 40. The image forming method according to claim 38, wherein the toner for developing an electrostatic latent image has a number average particle size of 2.2 to 9 μm. 41. When the particle diameter of the toner for developing an electrostatic latent image is D (μm), the natural logarithm lnD is plotted on the horizontal axis,
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 (m1) of the toner particles for electrostatic latent image development included in the most frequent class
The sum (M) of the relative frequency (m2) of the toner particles for electrostatic latent image development included in the class having the second highest frequency after the mode is 70% or more. 38
41. The image forming method according to any one of items 40 to 40. 42. The image forming method according to claim 38, wherein the electrostatic latent image developing toner is obtained by polymerizing a polymerizable monomer in an aqueous medium. 43. The toner for developing an electrostatic latent image according to claim 38, wherein the resin particles are associated with each other in an aqueous medium.
43. The image forming method according to any one of items 42 to 42. 44. Any one of claims 23, 31, and 38
An image forming apparatus comprising the steps of cleaning, forming an electrostatic latent image, developing, transferring and fixing using the image forming method described in the above section. 45. Contact transfer of a toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photoreceptor with a developer containing a toner for developing an electrostatic latent image. By transferring each image onto a transfer material using a method, and thereafter repeating the steps of separating, fixing, and cleaning, the toner for developing an electrostatic latent image used in an image forming method for forming a large number of images is used. The electrostatic latent image developing toner is characterized in that the variation coefficient of the shape factor is 16% or less, the number variation coefficient in the number particle size distribution is 27% or less, and the toner aggregation rate is 3 to 35%. For toner. 46. Contact transfer of a toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photosensitive member with a developer containing a toner for developing an electrostatic latent image. By transferring each image onto a transfer material using a method, and thereafter repeating the steps of separating, fixing, and cleaning, the toner for developing an electrostatic latent image used in an image forming method for forming a large number of images is used. In the toner for developing an electrostatic latent image, the ratio of the toner particles having no corners is 50% by number or more, the number variation coefficient in the number particle size distribution is 27% or less, and the toner aggregation rate is 3 to
35% of a toner for developing an electrostatic latent image. 47. A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on an electrophotographic photosensitive member with a developer containing a toner for developing an electrostatic latent image, and contact-transferring the toner image. By transferring each image onto a transfer material using a method, and thereafter repeating the steps of separating, fixing, and cleaning, the toner for developing an electrostatic latent image used in an image forming method for forming a large number of images is used. The toner for developing an electrostatic latent image contains 65% by number of toner particles having a shape coefficient in the range of 1.2 to 1.6.
As described above, the toner for developing an electrostatic latent image is characterized in that the variation coefficient of the shape coefficient is 16% or less and the toner aggregation rate is 3 to 35%. 48. The electrophotographic photoreceptor has a structure in which a photosensitive layer is provided on a conductive support, and the surface layer of the photosensitive layer contains a polycarbonate having an average molecular weight of 10,000 to 100,000. The method according to claim 1,
39. The image forming method according to any one of 9, 16, 23, 31, and 38. 49. The electrophotographic photoreceptor has a surface protective layer, and the surface protective layer contains a siloxane resin having a crosslinked structure.
The image forming method according to any one of items 23, 31, and 38. 50. The method according to claim 1, wherein the surface protective layer containing the siloxane resin contains a charge transporting structural unit as a part of a crosslinked structure. 2. The image forming method according to claim 1. 51. An image forming apparatus comprising the steps of cleaning, forming an electrostatic latent image, developing, transferring and fixing using the image forming method according to any one of claims 48 to 50.