JP2002023408A - Electrostatic latent image developing toner, method for image formation and device for image formation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic latent image developing toner having extremely excellent cleaning performance without causing image irregularity, black stripes or fog which are serious problems for the development of the method and device for image formation to obtain stable copied images of high picture quality for a long time, and to provide a method and device for image formation by using the toner. SOLUTION: In the method for image formation to repeat the processes of forming an electrostatic latent image by electrification and exposure on a photoreceptor, developing the latent image with a developer to form a toner image, transferring the toner image to a transfer material and cleaning and removing the residual toner on the photoreceptor by using a brush-like cleaning member and a rubber blade, the toner shows <=16% coefficient of variation in the shape coefficient and <=27% coefficient of variation in number in the distribution of grain size by number.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic latent image developing 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 an electrophotographic image forming method of the Carlson method used in a copying machine or the like, an electrostatic latent image is formed by uniformly charging a photoreceptor and then erasing the charge imagewise by exposure. Then, the electrostatic latent image is developed and visualized with toner, and then the toner is transferred to a recording material (transfer material) such as paper and then fixed to complete image formation.

However, not all of the toner on the photoreceptor is transferred, and some of the toner remains on the photoreceptor. Therefore, the photoreceptor is repeatedly used after a cleaning process. If cleaning is not complete, a good copied image without stain cannot be obtained when an image is repeatedly formed.

A typical cleaning means is a fur brush, a magnetic brush, a blade, or the like, but a blade is mainly used in terms of performance, configuration, and the like. At this time, a plate-shaped rubber elastic body is generally used as the blade member. However, there has been a problem that cleaning may not be performed completely using only the elastic rubber blade.

On the other hand, a brush has been conventionally proposed as another means of cleaning. However, it is difficult to obtain a cleaning performance equivalent to that of an elastic rubber blade using only a brush. However, there is a problem that the cost is increased and the installation space is secured, and at the same time, the mechanical stress applied to the photoconductor increases, and the life of the photoconductor is shortened.

Therefore, a technique using both the blade and the brush has been proposed. However, in an image forming method such as a high-speed color printer which has a large amount of adhesion and a large load on the cleaning member, the durability of the cleaning member is low. It was a big problem.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cleaning system using an elastic blade and a brush in combination to prevent the abrasion of the blade and the brush and to form a stable image for a long period of time. However, as a result of the study by the present inventors in view of the above situation, it is difficult to solve this problem only by examining the cleaning method and its conditions, and the shape of the toner particles of the toner to be cleaned is greatly involved. Turned out to be necessary.

[0008] That is, an object of the present invention is to prevent image unevenness, black streaks, and fogging, which are major problems in the development of an image forming method and an image forming apparatus capable of obtaining a high-quality and stable copied image for a long period of time. An object of the present invention is to provide an electrostatic latent image developing toner having extremely excellent cleaning performance, and an image forming method and an image forming apparatus using the same.

[0009]

As a result of intensive studies by the inventors, the object of the present invention can be attained by adopting one of the following constitutions as described in claims 1 to 51. I understood.

[1] A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer is transferred onto a transfer material, and then a brush-like image is formed on the photoreceptor. An image forming method in which a process of cleaning and removing residual toner by a cleaning member and a rubber blade is repeated, the image forming method adopting the following configurations 1) to 3). 1) An image forming method, wherein the toner has a shape coefficient variation coefficient of 16% or less and a number variation coefficient in a number particle size distribution of 27% or less. 2) An image forming method, wherein the toner has 50% by number or more of toner particles having no corners, and the number variation coefficient in the number particle size distribution is 27% or less. 3) An image forming method, wherein the toner has 65% by number or more of toner particles having a shape coefficient in the range of 1.2 to 1.6, and a variation coefficient of the shape coefficient is 16% or less.

In the above toner, the shape factor is 1.0 to 1.0.
It is desirable that the number of toner particles in the range of 1.6 is at least 65% by number, more preferably the number of toner particles whose shape factor is in the range of 1.2 to 1.6 is at least 65% by number.

[0012] Further, when the toner has 50
% Or more, and the number average particle diameter of the toner is 3 to 8
μm is preferred.

Further, when the particle diameter of the toner particles is D (μm), the natural logarithm lnD is plotted on the abscissa, and the abscissa is set to 0.1.
In the histogram showing the number-based particle size distribution divided into a plurality of classes at 23 intervals, the relative frequency (m1) of the toner particles included in the most frequent class and the toner included in the class having the second highest frequency after the most frequent class The sum (M) of the relative frequency (m2) of the particles is preferably 70% or more.

Further, it is preferable that the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium, and / or that the toner is formed by associating at least resin particles in an aqueous medium.

[2] The above image forming method is applied to an image forming apparatus having steps of cleaning, forming an electrostatic latent image, developing, transferring and fixing.

[3] A color toner image obtained by visualizing the electrostatic latent image formed on the photoreceptor is transferred onto the intermediate transfer member, and then transferred from the intermediate transfer member to a transfer material to form an image. Photoconductor, which carries a color toner image visualized from an electrostatic latent image using an image forming apparatus, an intermediate transfer body on which the color toner image on the photoconductor is overlaid and rotated, and A cleaning blade for scraping off the deposits adhering to the body, and a cleaning blade disposed upstream of the cleaning blade with respect to the rotation direction of the intermediate transfer member and rotating and rubbing the deposits adhering to the intermediate transfer member. An image forming method including a brush roller for dropping and repeating a process of cleaning and removing residual toner, wherein the image forming method employs the following configurations 1) to 3). 1) An image forming method, wherein the toner has a shape coefficient variation coefficient of 16% or less and a number variation coefficient in a number particle size distribution of 27% or less. 2) An image forming method, wherein the toner has 50% by number or more of toner particles having no corners, and the number variation coefficient in the number particle size distribution is 27% or less. 3) An image forming method, wherein the toner has 65% by number or more of toner particles having a shape coefficient in the range of 1.2 to 1.6, and a variation coefficient of the shape coefficient is 16% or less.

In the above toner, the shape factor is 1.0 to 1.0.
It is desirable that the number of toner particles in the range of 1.6 is at least 65% by number, more preferably the number of toner particles whose shape factor is in the range of 1.2 to 1.6 is at least 65% by number.

Further, when the toner has 50
% Or more, and the number average particle diameter of the toner is 3 to 8
μm is preferred.

Further, when the particle diameter of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is defined as 0.
In the histogram showing the number-based particle size distribution divided into a plurality of classes at 23 intervals, the relative frequency (m1) of the toner particles included in the most frequent class and the toner included in the class having the second highest frequency after the most frequent class The sum (M) of the relative frequency (m2) of the particles is preferably 70% or more.

Further, it is preferable that the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium, and / or that the toner is formed by associating at least resin particles in an aqueous medium.

[4] The image forming method of the above [3] is applied to an image forming apparatus having steps of cleaning, forming an electrostatic latent image, developing, transferring and fixing.

[5] A toner used for forming an image using the image forming method of the above [3] and having the steps of cleaning, forming an electrostatic latent image, developing, transferring and fixing.

The present inventors have found that the shape and distribution of a specific toner, as well as the particle size, specific "presence / absence of an angle", and the particle size distribution are important for solving the problems of the present invention. This has led to the completion of the present invention.

The inventors of the present invention have studied toner particles having a large amount of wear of the cleaning member. As a result, when the image forming process is repeated, toner particles having irregular shapes and toner particles having corner portions are found. The cleaning member tends to wear out easily. Although the reason for this is not clear, if the shape of the toner particles is irregular, the cleaning member is susceptible to mechanical stress,
It was presumed that this was due in part to excessive stress.

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 extensive studies, the present inventors have found that the use of a toner having a shape coefficient variation coefficient of 16% or less and a number variation coefficient in the number particle size distribution of 27% or less provides cleaning properties and fine lines. They have found that excellent reproducibility and high quality image quality can be formed over a long period of time, and have completed the present invention.

That is, by making the distribution of the shape of the toner itself uniform, the friction applied to the cleaning member is reduced, the toner can be prevented from slipping, and the occurrence of filming / scratch on the photosensitive member can be suppressed. Can be prevented from occurring.

The present inventors have conducted intensive studies. As a result, the same effect as described above can be obtained with toner particles having no corners, even if the variation in the shape is somewhat large in order to reduce polishing and wear of the cleaning member by toner. I found to do.
That is, by using a toner having 50% by number or more of toner particles having no corner and having a number variation coefficient of 27% or less in the number particle size distribution, excellent cleaning property and fine line reproducibility and high quality image quality can be obtained for a long time. It was found that it could be formed over

Further, as a result of intensive studies, the present inventors have made it possible to equalize the load applied to the cleaning member even when the specific shape is made uniform.
It has been found that a similar effect is exhibited. That is, by using toner having 65% by number or more of toner particles having a shape coefficient in the range of 1.2 to 1.6 and a coefficient of variation of the shape coefficient of 16% or less, cleaning properties and fine line reproducibility are obtained. And high quality image quality can be formed over a long period of time.

In the description of the present invention, a transfer member on which a toner image is finally fixed is distinguished from an intermediate transfer member as a transfer material.

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

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

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

In the structure according to the first and ninth aspects, it is preferable that the toner particles having the shape factor in the range of 1.0 to 1.6 are 65% by number or more, more preferably 70% by number. % Or more. More preferably,
This means that the number of toner particles having a shape coefficient in the range of 1.2 to 1.6 is at least 65% by number, and 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 65% by number or more, the load applied to the cleaning member becomes uniform, and the durability of the member increases.

Further, in the structure of the sixteenth aspect, it is necessary that the number of toner particles whose shape factor is in the range of 1.2 to 1.6 is 65% by number or more.
70% by number or more.

The method of controlling the shape factor is not particularly limited. For example, a method of spraying toner particles in a hot air flow, a method of repeatedly applying mechanical energy by an impact force in a gas phase, or a method of adding a toner particle in a solvent that does not dissolve a toner to give a swirling flow, etc. To prepare a toner having a shape factor of 1.0 to 1.6 or 1.2 to 1.6, and then add it to a normal toner so as to fall within the range of the present invention. There is. Further, the whole shape is controlled at the stage of preparing a so-called polymerization toner, and the shape factor is set to 1.0 to 1.6,
Alternatively, there is a method in which the toner prepared in the range of 1.2 to 1.6 is similarly added to a normal toner for adjustment.

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

The coefficient of variation of the shape factor of the toner of the present invention is calculated from the following equation. Coefficient of variation = (S / K) × 100 (%) (where S represents the standard deviation of the shape factor of 100 toner particles, and K represents the average value of the shape factor.) Is 16% or less, preferably 14% or less. When the variation coefficient of the shape factor is 16% or less, the amount of toner passing through the elastic rubber blade is significantly reduced. Further, the charge amount distribution becomes sharp, and the image quality is improved.

In order to uniformly control the shape factor of the toner and the variation coefficient of the shape factor without variation among lots, resin particles (polymer particles) are being formed in a process of polymerization, fusion, and shape control. The proper process end time may be determined while monitoring the characteristics of the toner particles (colored particles).

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

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

The number particle size distribution and the number variation coefficient of the toner of the present invention are measured with a Coulter Counter TA-II or a Coulter Multisizer (manufactured by Coulter Corporation). In the present invention, a Coulter Multisizer was used by connecting an interface (manufactured by Nikkaki Co., Ltd.) for outputting a particle size distribution and a personal computer. The aperture used in the Coulter Multisizer is 100 μm and the aperture is 2 μm.
The volume and number of the above toners were measured to calculate the particle size distribution and the average particle size. The number particle size distribution represents the relative frequency of the toner particles with respect to the particle size, and the number average particle size represents the median size in the number particle size distribution.

The number variation coefficient in the number particle size distribution of the toner is calculated from the following equation. Number variation coefficient = (S / Dn) × 100 (%) (where S represents a standard deviation in the number particle size distribution, and D
n 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 is sharpened, the transfer efficiency is increased, 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 a liquid, there is a method of separating and collecting toner particles according to a sedimentation speed difference caused by a difference in toner particle diameter by controlling a rotation speed by using a centrifugal separator.

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

The toner particles having no corners according to the present invention are toner particles having substantially no protrusions on which electric charges are concentrated or protrusions which are easily worn by stress. The particles are called cornerless toner particles.
That is, as shown in FIG. 10, when the toner particle is a circle having a major axis of L and a radius R of L / 10, and the inside is in contact with the toner particle peripheral line at one point, the circle is completely formed. Corners that do not substantially protrude from the outside of the toner are called toner particles having no corners. The case where the protrusion does not substantially protrude means that one or more protrusions have a protruding circle. In addition, the major axis of the toner particle refers to 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 toner particles are enlarged by a scanning electron microscope is taken, 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 the toner particles having no corner is at least 50% by number, 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 and 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. In addition, the amount of toner particles that are easily worn or broken and the number of toner particles having a portion where charges are concentrated are reduced, the charge amount distribution is sharpened, the chargeability is stabilized, and good image quality can be formed over a long period of time.

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

In the polymerization toner formed by associating or fusing the 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 adjusting the conditions such as the temperature, the number of rotations of the stirring blade, and the stirring time, toner having no corners can be obtained. These conditions vary depending on the physical properties of the resin particles. For example, when the rotation speed is higher than the glass transition temperature of the resin particles and the number of rotations is high, the surface becomes smooth and a toner having no corners can be formed.

The toner of the present invention preferably has a number average particle diameter of 3 to 8 μm. When toner particles are formed by a polymerization method, the particle diameter can be controlled by the concentration of the coagulant, the amount of the organic solvent added, the fusing time, and the composition of the polymer itself.

When the number average particle diameter is 3 to 8 μm, both the cleaning property and the image quality improvement such as the fine line reproducibility and the dot reproducibility are achieved.

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 sum (M1) of the relative frequency (m1) of the toner particles included in the most frequent class and the relative frequency (m2) of the toner particles included in the class having the second highest frequency after the most frequent class. ) 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 is narrowed. Thus, the occurrence of selective development can be reliably suppressed.

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

(Measurement conditions) (1) Aperture: 100 μm (2) Sample preparation method: electrolytic solution [ISOTON R-1
1 (manufactured by Coulter Scientific Japan)
An appropriate amount of a surfactant (neutral detergent) is added to 50 to 100 ml and stirred, and 10 to 20 mg of a measurement sample is added thereto. This system is prepared by subjecting it to a dispersion treatment with an ultrasonic disperser for 1 minute.

[0058]

BEST MODE FOR CARRYING OUT THE INVENTION The toner of the present invention is prepared 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. , An organic solvent, a coagulant and the like can be added to the mixture for association. At the time of association, a method of preparing by mixing and mixing with a dispersion liquid such as a release agent or a colorant necessary for the composition of the toner,
Examples include a method in which toner constituents such as a release agent and a colorant are dispersed in a monomer and emulsion polymerization is performed. Here, the association means that a plurality of resin particles and colorant particles are fused.

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

That is, a coloring agent and, if necessary, various constituent materials such as 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 these various constituent materials are dissolved or dispersed is dispersed in an aqueous medium containing a dispersion stabilizer into oil droplets of a desired size as a toner using a homomixer, a homogenizer, or the like. Thereafter, the stirring mechanism is moved to a reaction device, which is a stirring blade described later, and heated to cause the polymerization reaction to proceed. After completion of the reaction, the toner of the present invention is prepared by removing the dispersion stabilizer, filtering, washing and drying.

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. 5-265
252, JP-A-6-329947, and JP-A-9-15904. That is, a method of associating a plurality of resin particles and dispersed particles of a constituent material such as a colorant, or a plurality of fine particles composed of a resin and a colorant, particularly, after dispersing these in water using an emulsifier, the critical aggregation concentration At the same time as adding the above flocculant and salting out, the formed polymer itself is heated and fused at a temperature equal to or higher than the glass transition temperature to gradually form a fused particle, thereby gradually growing the particle size. At this point, a large amount of water was added to stop the growth of the particle diameter, and the surface was smoothened by heating and stirring to control the shape. The toner of the invention can be formed. Here, an organic solvent that 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,
Methacrylate derivatives such as isobutyl methacrylate, t-butyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, lauryl methacrylate, phenyl methacrylate, diethylaminoethyl methacrylate, and dimethylaminoethyl methacrylate. , Methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, isobutyl acrylate,
Acrylic ester derivatives such as n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate, phenyl acrylate, and the like, olefins such as ethylene, propylene, and isobutylene, vinyl chloride, vinylidene chloride, and vinyl bromide , Vinyl fluoride such as vinyl fluoride and vinylidene fluoride; vinyl esters such as vinyl propionate, vinyl acetate and vinyl benzoate; vinyl ethers such as vinyl methyl ether and vinyl ethyl ether; vinyl methyl ketone and vinyl ethyl ketone , Vinyl ketones such as 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, acrylonitrile, Acrylonitrile, there are acrylic acid or methacrylic acid derivatives such as 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 Azo or diazo polymerization initiators such as nitrile and azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide , Dicumyl peroxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis-
Examples thereof include peroxide-based polymerization initiators such as (4,4-t-butylperoxycyclohexyl) propane and tris- (t-butylperoxy) triazine, and polymer initiators having a peroxide in a side chain. .

When 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, a surfactant generally used as a surfactant such as polyvinyl alcohol, gelatin, methyl cellulose, sodium dodecylbenzenesulfonate, ethylene oxide adduct, and higher alcohol sodium sulfate can be used as a dispersion stabilizer.

The resin excellent in the present invention preferably has a glass transition point of 20 to 90 ° C. and a softening point of 8 ° C.
The thing of 0-220 ° C is preferred. The glass transition point is measured by a differential calorimetric analysis method, and the softening point can be measured by a Koka flow tester. Furthermore, these resins have a number average molecular weight (Mn) of 10 as measured by gel permeation chromatography.
00 to 100,000, 200 in terms of mass average molecular weight (Mw)
Those having 0 to 1,000,000 are preferred. Further, as a molecular weight distribution, Mw / Mn is 1.5 to 100, particularly 1.8.
-70 are preferred.

The flocculant 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.
These may be used in combination.

It is preferable that these coagulants are 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.
7, 601 (1960), edited by The Society of Polymer Science, Japan, and the like, 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, the 、 (zeta) potential of the dispersion is measured, and the salt concentration at which this value changes is defined as the critical aggregation concentration. You can also ask.

The amount of the coagulant of the present invention may be not less than the critical coagulation concentration, but is preferably 1.2 to the critical coagulation concentration.
It is better to add it at least twice, more preferably at least 1.5 times.

The solvent which is infinitely soluble means a solvent which is infinitely soluble in water. The 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 infinitely dissolved 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, filter it, and then carry out fluid drying of a slurry containing 10% by mass or more of water based on the particle. 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 of the present invention contains at least a resin and a colorant, but may contain a releasing agent or a charge control agent as a fixing property improving agent, if necessary. 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 of the present invention, carbon black, magnetic substance, dye, pigment and the like can be arbitrarily used. As the carbon black, channel black, furnace black, acetylene black, and the like can be used.
Thermal black, lamp black and the like are used. Ferromagnetic metals such as iron, nickel, and cobalt as magnetic materials,
Alloys containing these metals, compounds of ferromagnetic metals such as ferrite and magnetite, alloys that do not contain ferromagnetic metals but show ferromagnetism by heat treatment, such as manganese-copper-
An alloy of a type called a Heusler alloy such as aluminum, manganese-copper-tin, chromium dioxide, or 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 a mixture 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 a mixture 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 coagulation by adding a coagulant to color the polymer, or a process of polymerizing monomers. And a method of adding a colorant, polymerizing, and forming colored particles 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) or low molecular weight polyethylene as a fixing property improving agent may be added.

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

The particles of the charge control 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.

A suspension polymerization 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 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 shown in FIG. 1 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 turbulent flow 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 formed in part, it acts in a direction in which the flow of the fluid stagnates due to the presence of the turbulent flow,
As a result, the shape cannot be controlled because the slip with respect to the particles is reduced.

A stirring tank provided with a stirring blade which can be preferably used will be described with reference to the drawings. FIG. 1 shows an example of a stirring tank provided with a stirring blade commonly used in the related art. A more preferred embodiment is one having a two-stage stirring blade as shown in FIG. 2 (however, as will be described in detail later, it is better to slightly change the shape of the stirring blade, and to have a baffle plate which is a turbulence forming member. Is better). A rotating shaft 3 is suspended from the center of a vertical cylindrical stirring tank 2 having a heat exchange jacket 1 mounted on 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 90 degrees (°).
Less is better. The lower limit of the intersection angle is not particularly limited, but may be about 5 ° or more, preferably 10 ° or more. FIG. 3 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.

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. Then, 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. 2, the arrow indicates the rotation direction, 7 indicates the upper material inlet, and 8 indicates the lower material inlet. Also, 9 shown in FIG. 1 is a turbulence forming member (baffle plate) for making the stirring effective.
It is.

Here, the shape of the stirring blade is not particularly limited, but it has a rectangular plate shape, a notch in a part of the blade, and one or more middle holes, so-called slits, in the center. Things and the like can be used. These examples are described in FIG. In FIG. 4, (a) shows a stirring blade without a hole, (b) a large hole 6 in the center, (c) a horizontally long hole 6, and (d). There is a vertically long middle hole 6. Further, these may be different from each other in the upper hole and the lower hole, or may be the same.

FIGS. 5 to 9 show examples of preferable structures which can be used as the structure of the stirring blade. FIG. 5 shows a configuration having a projection at the end of the stirring blade and / or a bent portion at the end, FIG. 6 shows a configuration having a slit at the lower stage of the stirring blade and bending and a projection at the end, and FIG. FIG. 8 shows a configuration in which an upper stirring blade has a gap and an end of a lower stirring blade has a bent portion and a projection, and FIG. 9 shows a configuration in which the stirring blade has three stages. Are respectively shown. The angle of the bent portion at the end of the stirring blade is preferably about 5 to 45 °.

The stirring blade having the bent portion and the projection (4 'or 5') projecting upward or downward (4 "or 5") effectively generates a turbulent flow.

The gap between the upper and lower stirring blades having the above configuration is not particularly limited, but it is preferable that at least a gap is provided 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 has a width of 0.5 to 50%, preferably 1 to 30% with respect to the liquid level in the stationary state.

Further, 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. 2 shows an example of a stirring blade and a stirring tank used for forming a laminar flow in the suspension polymerization method.
There are the following. 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 to form the turbulent flow described above, the upper stirring blade is arranged with the intersection angle α that precedes the rotation direction with respect to the lower stirring blade. 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, but is preferably formed by a continuous surface such as a rectangular plate 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. By controlling the heating temperature, the number of rotations for stirring, and the time in the control step, 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 reactor is made laminar and the stirring blade and the stirring tank which can make the internal temperature distribution uniform are used. Temperature in the deposition process and the shape control process,
By controlling the number of rotations and time, 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 when fusion is performed in a place where a laminar flow is formed, strong stress is not applied to the particles that are undergoing aggregation and fusion (association or aggregated particles) and the flow is accelerated in a laminar flow. It is estimated that the shape distribution of the fused particles becomes uniform as a result of the uniform temperature distribution in the stirring tank.
Further, 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 the stirring blade and stirring tank used for the polymerization method toner for associating or fusing the resin particles, the same stirring blades and stirring tank as those used for forming a laminar flow in the above-mentioned suspension polymerization method can be used. The following 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,
Similar to the stirring blade used in the suspension polymerization method described above, the upper stirring blade is arranged with a crossing angle α that precedes the lower stirring blade in the rotation direction with respect to the lower stirring blade. Is preferred.

The shape of the stirring blade can 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. Those formed by continuous surfaces such as plate-like ones are preferable, and may have a curved surface.

Further, in the toner of the present invention, more effects can be exhibited by adding and using fine particles such as inorganic fine particles and organic fine particles as an external additive. The reason for this is presumed that the embedding and detachment of the external additive can be effectively suppressed, so that the effect is remarkable.

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. preferable. The degree of the hydrophobizing treatment is not particularly limited, but a methanol wettability of 40 to 95 is preferable. Methanol wettability is to evaluate the wettability to methanol. In this method, an inorganic fine particle to be measured is added to 50 ml of distilled water placed in a beaker having a capacity of 200 ml.
Weigh 2 g and add. Methanol is slowly dropped from a burette whose tip is immersed in the liquid until the entire inorganic fine particles are wet with stirring slowly. When 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.

Degree of hydrophobicity = (a / (a + 50)) × 100 The amount of the external additive to be added is 0.1 to 5.
0 mass%, preferably 0.5 to 4.0 mass%. Various external additives may be used in combination.

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

In the case of the pulverized toner, the shape factor is 1.2 to
The ratio of the 1.6 toner particles is about 60% by number. The variation coefficient of the shape factor is about 20%. Further, in the pulverization method, in order to reduce the particle size while repeating crushing, the toner particles have many corners, and the ratio of toner particles having no 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. In addition, the number variation coefficient in the number particle size distribution is about 30% when the classification operation after the pulverization is performed once, and the classification operation needs to be further repeated to reduce the number variation coefficient to 27% or less. There is.

In the case of the toner obtained by the suspension polymerization method, the toner is conventionally polymerized in a laminar flow, so that substantially spherical toner particles are obtained. For example, in the toner described in JP-A-56-130762, The proportion of toner particles having a coefficient of 1.2 to 1.6 is about 20% by number, the variation coefficient of the shape coefficient is also about 18%, and the proportion of toner particles having no corners is also about 85% by number. Further, as described above in the method for controlling the number variation coefficient in the number particle size distribution, mechanical shearing is repeated for a large oil droplet of a polymerizable monomer to reduce the oil droplet to a size of a toner particle. Therefore, the distribution of oil droplet diameters is widened, and the particle size distribution of the obtained toner is wide, and the number variation coefficient is as large as about 32%. Therefore, a classification operation is required to reduce the number variation coefficient. .

Polymerized toners formed by associating or fusing resin particles are described in, for example,
In the toner described in JP-A-186253, the ratio of the toner particles having a shape coefficient of 1.2 to 1.6 is 60% by number.
The variation coefficient of the shape factor is about 18%, and the ratio of toner particles without corners is about 44% by number. The ratio of toner particles without corners is about 55% by number. Further, the particle size distribution of the toner is wide and the number variation coefficient is 30%, and a classification operation is required to reduce the number variation coefficient.

The cleaning system which can use the toner of the present invention is shown below. FIG. 11 is a schematic configuration diagram of a developing unit to which a cleaning method that can be suitably used in the image forming method of the present invention is applied.

In FIG. 11, reference numeral 11 denotes a photosensitive member (electrostatic latent image forming member), 12 denotes a charger, 13 denotes a developing device, 14 denotes a transfer device,
5 is a separator, 22 is a cleaning device, 221 is a rubber blade, 224 is a columnar brush support, 223 is a toner adhesion layer, and 222 is a brush roller.

The material of the brush according to the present invention may be any material, but it is preferable to use a fiber-forming polymer having hydrophobicity and a high dielectric constant.
Examples of such high-molecular polymers include rayon, nylon, polycarbonate, polyester, methacrylic resin, acrylic resin, polyvinyl chloride, polyvinylidene chloride, polypropylene, polystyrene, polyvinyl acetate, styrene-butadiene copolymer, and vinylidene chloride. -Acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol formaldehyde resin, styrene-alkyd resin, polyvinyl acetal (for example, polyvinyl acetal) Butyral) and the like. These resins can be used alone or as a mixture of two or more.
In particular, preferably rayon, nylon, polyester,
Acrylic and polypropylene.

The brush may be conductive or insulative, and may be a material in which a constituent material contains a low-resistance substance such as carbon and the resistance is adjusted to an arbitrary value.

The support used in the brush of the present invention is mainly a metal such as stainless steel or aluminum, paper, or the like.
Plastic or the like is used, but is not limited thereto.

Also, if necessary, the brush roller 222 may be used.
A member (flicker) may be provided for knocking off the toner and foreign matter adhered to the brush from the brush.

Rubber blade 221 used in the present invention
Has a configuration in which a support member 224 is provided with a free end as shown in FIG.

It is preferable that the free end of the rubber blade is in pressure contact with (counter) the rotation direction of the photosensitive member.

The rubber hardness of the rubber blade is JIS A
60-70 °, rebound resilience 30-70%, Young's modulus 3
000-6000 kPa, thickness 1.5-3.0 mm,
Free length is 7-12mm, pressing force on photoreceptor is 5-30m
N / cm is preferable, but not particularly limited.

A typical example of the electrostatic latent image forming body is an electrophotographic photosensitive member. Specific examples include an inorganic photosensitive member such as selenium and arsenic selenium, an amorphous silicon photosensitive member, and an organic photosensitive member. be able to. Particularly preferred is an organic photoreceptor having a laminated structure of a charge transport layer and a charge generation layer.

The image forming method is not particularly limited, but can be preferably used in a method using a so-called intermediate transfer member. 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 a photosensitive drum as a photosensitive member, and these visible images are formed on an intermediate transfer member. The method is also preferably used in a system in which a color image is obtained by sequentially transferring and collectively transferring 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 an image of a plurality of colors is formed in an image forming section, and the images are sequentially superimposed and transferred on the same intermediate transfer member will be described with reference to FIG.

The image forming apparatus for obtaining a color image according to the present invention includes a plurality of image forming units, each of which forms a visible image (toner image) of a different color, and forms the toner image. This is an image forming method in which the images are sequentially transferred onto the same transfer member.

Here, the first, second, third and fourth image forming units Pa, Pb, Pc and Pd are arranged side by side.
Each of the image forming units includes photosensitive drums 1a, 1b, 1c, and 1d as electrostatic latent image forming bodies.

The photosensitive drums 1a to 1d have latent image forming portions 2a, 2b, 2c and 2d and developing portions 3a and 3
b, 3c and 3d, a transfer discharger 4a, 4b, 4c and 4d, and a cleaning device 5a having a brush-like cleaning member and a rubber blade according to the present invention.
5b, 5c and 5d 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 photosensitive drum 1a of the first image forming unit Pa by the latent image forming unit 2a. The latent image is formed into a visible image by a developer having a yellow toner in the developing section 3a, and is transferred to the intermediate transfer member 18 in the transfer discharging section 4a.

On the other hand, while the yellow image is being transferred to the intermediate transfer member 18 as described above, a magenta component color latent image is formed on the photosensitive drum 1b in the second image forming portion Pb, and then the developing portion At 3b, a visible image is formed with a developer containing magenta toner. This visible image (magenta toner image) is superimposed on a predetermined position of the intermediate transfer body 18 when the intermediate transfer body, which has been transferred in the first image forming unit Pa, is carried into the transfer discharge unit 4b. Transcribed.

Hereinafter, third and fourth steps are performed in the same manner as described above.
The cyan and black images are formed by the image forming units Pc and Pd, and the cyan and black colors are transferred onto the same intermediate transfer member in a superimposed manner. When such an image forming process is completed, the intermediate transfer member 18
A multicolor superimposed image is obtained on top. On the other hand, the photosensitive drums 1a, 1b, 1c and 1d, to which the transfer has been completed, have the residual toner removed by the cleaning devices 5a, 5b, 5c and 5d, and are provided for the subsequent latent image formation.

In the above image forming apparatus, the intermediate transfer member 18 is used.
8 is conveyed from the right side to the left side, passes through the transfer discharge sections 4a, 4b, 4c and 4d in the image forming sections Pa, Pb, Pc and Pd in the course of the transfer, and undergoes transfer.

In this image forming method, in order to transport the intermediate transfer member, a transport belt using a mesh of Tetron (registered trademark) fiber, a polyethylene terephthalate-based resin, and a polyimide-based resin from the viewpoint of ease of processing and durability. In general, a thin dielectric sheet such as a urethane resin is used as a support, and an intermediate transfer layer is coated thereon.

When the intermediate transfer member 18 passes through the fourth image forming portion Pd, an AC voltage is applied to the neutralizer and the intermediate transfer member 1
8 is neutralized, and the toner image is collectively transferred to the transfer material S.
Thereafter, the transfer material enters the fixing device 17, where the image is fixed, and is discharged from the discharge port 20.

In the figures, 13a, 13b, 13c, 13
d is a separation static eliminator. The intermediate transfer body 18 after the transfer of the toner image is cleaned by a cleaning device 19 also using a brush-like cleaning member and a rubber blade.
The residual toner is cleaned to prepare for the next image formation.

As described above, a multicolor superimposed image is formed on a long intermediate transfer member 18 such as a conveyor belt, and is transferred onto a transfer material at a time and fixed. Each of the image forming units may include an independent intermediate transfer member, and then transfer the image onto the transfer material sequentially from each intermediate transfer member.

As a preferred fixing method used in the present invention, a so-called contact heating method can be used. In particular, examples of the contact heating method include a heat and pressure fixing method, a heat roll fixing method, and a pressure contact heat fixing method in which fixing is performed by a rotating pressing member including a fixedly disposed heating element.

In the hot roll fixing method, in many cases, a heat source is placed inside a metal cylinder made of iron, aluminum, or the like, the surface of which is coated with tetrafluoroethylene or polytetrafluoroethylene-perfluoroalkoxyvinyl ether copolymer or the like. And a lower roller made of silicone rubber or the like.
A typical example of the heat source is one having a linear heater and heating the surface temperature of the upper roller to about 120 to 200 ° C. In the fixing section, pressure is applied between the upper roller and the lower roller to deform the lower roller and form a so-called nip. The nip width is 1 to 12 mm, preferably 3.5 to 9 mm. The fixing linear speed is 40 to 600 mm /
sec is preferred. When the nip is narrow, heat cannot be uniformly applied to the toner, causing uneven fixing. On the other hand, if the nip width is wide, melting of the resin is promoted, and the fixing offset becomes excessive, which causes a problem.

A fixing cleaning mechanism may be provided for use. As this method, a method in which a silicone oil is supplied to a roller or a film after fixing, or a method in which a silicone oil-impregnated pad, roller, web or the like is used for cleaning can be used.

Next, a description will be given of a fixing method using a rotating pressing member including a fixedly arranged heating element preferably used in the present invention.

This fixing system is a system in which a heating member fixedly arranged and a pressing member which is in pressure contact with the heating member and closely adheres the recording material to the heating member via a film via a film are used for pressure-heating fixing.

In this press-contact heating fixing device (fixing device), the heating element has a smaller heat capacity than a conventional heating roller, and has a linear heating section in a direction perpendicular to the transfer material passing direction. The maximum temperature of the part is 100-300 ° C.

Incidentally, the press-contact heat fixing means fixing the unfixed toner image by pressing the unfixed toner image against a heating source, such as a method of passing a recording material containing unfixed toner between a heating member and a pressing member as usually used. How to By doing so, the heating is performed quickly, so that the fixing speed can be increased. However, it is difficult to control the temperature, and the so-called residual toner is adhered to the unfixed toner directly, such as the surface of the heating source, where the unfixed toner is pressed. There is also a problem that a toner offset is likely to occur and a failure such as a winding of the transfer material around the fixing device is apt to occur.

In this fixing method, the low heat capacity linear heating element fixedly supported by the apparatus has a thickness of 0.2 to 5.0 mm.
0 mm, more preferably 0.5 to 3.5 mm and width 10
A resistance material is applied to an alumina substrate having a length of 240 to 400 mm and a length of 240 to 400 mm, and is supplied with electricity from both ends.

The energization is performed by changing the pulse width according to the temperature and the amount of energy release controlled by the temperature sensor with a pulse waveform of DC 100 V and a cycle of 25 msec. In the case of the temperature T1 detected by the temperature sensor in the low heat capacity linear heating element, the surface temperature T2 of the film facing the resistance material is lower than T1. Here, T1 is preferably 120 to 220 ° C., and the temperature of T2 is T1
Is preferably 0.5 to 10 ° C. lower than the temperature of
Further, the film material surface temperature T3 at a portion where the film is separated from the toner surface is substantially equal to T2. The film moves in the direction indicated by the central arrow in FIG. 14 described below while being in contact with the heating element whose energy and temperature are controlled in this manner.

Next, FIG. 14 is a sectional view showing the structure of the fixing device. In FIG. 14A, reference numeral 24 denotes a low-heat-capacity linear heating body fixedly supported by the apparatus. As an example, a resistive material 26 is formed on an alumina substrate 25 having a height of 10 mm, a width of 10 mm, and a longitudinal length of 240 mm. It is coated to 1.0 mm and is energized from both ends in the longitudinal direction.

The energization is carried out, for example, at a DC voltage of 100 V and a pulse-like waveform having a period of 2.0 msec.
The temperature is controlled by the signal from the controller. For this reason, the pulse width is changed in accordance with the energy release amount, and the range is, for example, 0.5 to 5 msec.

The transfer material S carrying the unfixed toner image 33 is brought into contact via the film 28 moved to the heating member controlled as described above, and the toner is thermally fixed.

The film used here moves without generating wrinkles while being tensioned by the driving roller 29 and the driven roller 30. Reference numeral 35 denotes a pressure roller having a rubber elastic layer formed of silicone rubber or the like, and presses the heating body through the film at a total pressure of 40 to 200N. The unfixed toner image 33 on the recording material S is guided to the fixing unit by the entrance guide 36, and a fixed image is obtained by the above-described heating.

The endless belt has been described above. However, as shown in FIG. 14B, a film sheet feeding shaft 31 and a winding shaft 32 may be used, and the fixing film may be an endless one.

[0142]

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

(Toner Production Example 1: Example of Emulsion Polymerization Association Method)
9. 0.90 kg of sodium n-dodecyl sulfate and pure water
Add 0 l and stir to dissolve. To this solution, add Regal 330
1.20 kg of R (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 is referred to as “colorant dispersion liquid 1”. A solution composed of 0.055 kg of sodium dodecylbenzenesulfonate and 4.0 l of ion-exchanged water is referred to as “anionic surfactant solution A”.

Nonylphenol polyethylene oxide 10 mol adduct 0.014 kg and ion exchanged water 4.0 L
Is referred to as “nonionic surfactant solution B”.
223.8 g of potassium persulfate was added to 12.0 L of deionized water.
Is referred to as "initiator solution C".

A 100-liter GL (glass lining) reactor equipped with a temperature sensor, a cooling pipe, and a nitrogen introducing device was charged with W.
3.41 kg of AX emulsion (polypropylene emulsion having a number average molecular weight of 3,000: number average primary particle size = 120 nm / solid concentration = 29.9%), the whole amount of “anionic surfactant solution A” and “nonionic surfactant solution B” Add the whole amount and start stirring. The configuration of the stirring blade was the configuration shown in FIG. The angle and the overall size of the stirring blade are shown in the separate table. Next, 44.0 L of ion-exchanged water is added.

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, n-butyl acrylate 2.88 kg, methacrylic acid 1.04 kg and t-dodecyl mercaptan 54
8 g are added dropwise. After 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 less, stirring was stopped, and the mixture was filtered with a pole filter to obtain “latex-A”.

Incidentally, the glass transition temperature of the resin particles in the latex-A is 57 ° C., the softening point is 121 ° C., and the molecular weight distribution is as follows: weight average molecular weight = 12.7 million, weight average particle size is 12
It was 0 nm.

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

Potassium persulfate (Kanto Chemical) 200
A solution obtained by dissolving 7 g in 12.0 l of ion-exchanged water is 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. 4A) was mixed with a wax emulsion (polypropylene emulsion having a number average molecular weight of 3000: number average). Primary particle size = 120 nm / solid content 29.9%) 3.4
1 kg, the whole amount of “anionic surfactant solution D” and the whole amount of “nonionic surfactant solution E” are added, and stirring is started.
Next, 44.0 L of ion-exchanged water is charged. Heating is started, and when the liquid temperature reaches 70 ° C., “Initiator solution F” is added. Then, 11.0 kg of styrene, 4.00 kg of n-butyl acrylate and 1.04 methacrylic acid were used.
kg and 9.02 g of t-dodecylmercaptan are added dropwise. After the completion of dropping, the temperature of
The mixture was heated and stirred for 6 hours while controlling at 2 ° C. ± 2 ° C. Further, the liquid temperature was raised to 80 ° C. ± 2 ° C., and the mixture was heated and stirred for 12 hours. The liquid temperature is cooled to 40 ° C. or less, and the stirring is stopped. The solution was filtered through a Pall filter, and this filtrate was designated as "latex-B".

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

Sodium chloride as salting-out agent 5.36k
g in ion-exchanged water 20.0 L is referred to as “sodium chloride solution G”.

A solution obtained by dissolving 1.00 g of a fluorine-based nonionic surfactant in 1.00 L of ion-exchanged water is referred to as “nonionic surfactant solution H”.

A 100 L S equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a particle size and shape monitoring device.
In a US reactor (the configuration of the stirring blade is shown in FIG. 4B), the latex-A = 20.0 kg, the latex-B = 5.2 kg, the colorant dispersion 1 = 0.4 kg, and the ion-exchange water 20.0 kg and stirred. Then, 40
The mixture was heated to ℃, and sodium chloride solution G, 6.00 kg of isopropanol (manufactured by Kanto Chemical Co.) and nonionic surfactant solution H were added in this order. Thereafter, after standing for 10 minutes, the temperature was raised, and the temperature was raised to a liquid temperature of 85 ° C. in 60 minutes.
Heating and stirring at 85 ± 2 ° C for 0.5 to 3 hours to grow the particle size while salting out / fusing. Next, 2.1 l of pure water is added to stop the particle size growth.

In a 5 L reaction vessel equipped with a temperature sensor, a cooling pipe, and a monitoring device for particle size and shape (the structure of the stirring blade is shown in FIG. 4B), 5.0 kg of the fused particle dispersion prepared above was placed. At a liquid temperature of 85 ° C. ± 2 ° C.
The shape was controlled by heating and stirring for 15 hours. Thereafter, the temperature is cooled to 40 ° C. or less, and the stirring is stopped. Next, using a centrifuge,
Classify in the liquid by centrifugal sedimentation method, opening 45μm
And the filtrate is used as an association liquid. Then
Using a Nutsche, non-spherical particles in the form of a wet cake were collected by filtration from the association liquid. Thereafter, the substrate 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 then dried at a temperature of 60 ° C. using a fluidized bed drier. 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 obtain a toner by an emulsion polymerization association method.

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. And the coefficient of variation of the particle size distribution was adjusted arbitrarily to obtain toner 1 shown in Tables 1 and 2.
~ 50 was obtained.

[0158]

[Table 1]

[0159]

[Table 2]

(Toner Production Example 2: Example of Emulsion Polymerization Association Method)
Toners 51 to 59 shown in Table 3 were obtained in the same manner as in Toner Production Example 1 except that 1.05 kg of a benzidine-based yellow pigment was used instead of carbon black as the coloring agent.

(Toner Production Example 3: Example of Emulsion Polymerization Association Method)
Toners 60 to 68 shown in Table 3 were obtained in the same manner as in Toner Production Example 1, except that 1.20 kg of a quinacridone-based magenta pigment was used instead of carbon black as the coloring agent.

(Toner Production Example 4: Example of Emulsion Polymerization Association Method)
Toners 69 to 77 shown in Table 3 were obtained in the same manner as in Toner Production Example 1 except that 0.60 kg of a phthalocyanine-based cyan pigment was used instead of carbon black as the coloring agent.

(Toner Production Example 5: Example of Suspension Polymerization Method) Styrene = 165 g, n-butyl acrylate = 35 g, carbon black = 10 g, metal di-t-butylsalicylate = 2 g, styrene-methacrylic acid copolymer = 8
g, paraffin wax (mp = 70 ° C.) = 20 g = 6
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, 0.10 g of ion-exchanged water was added to 710 g.
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 13000 rpm with a TK homomixer to prepare a suspension in which tricalcium phosphate was dispersed. The above polymerizable monomer composition was added to this suspension, and the mixture was mixed with a TK homomixer at 1000.
The mixture was stirred at 0 rpm for 20 minutes to granulate the polymerizable monomer composition. Thereafter, the reaction was carried out at 75 to 95 ° C. for 5 to 15 hours using a reaction apparatus having the configuration of the stirring tank shown in FIG. 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. 100 of the obtained colored particles
1 part by mass of silica fine particles was externally added and mixed with the mass part by a Henschel mixer to obtain a toner by a suspension polymerization method.

By monitoring during the polymerization and controlling the liquid temperature, the number of rotations of the stirring, and the heating time, the variation coefficient of the shape and the shape coefficient are controlled. The coefficients were arbitrarily adjusted to obtain toners 78 to 83 shown in Table 4.

(Toner Production Example 6: Example of Suspension Polymerization Method) In toner production example 5, the structure of the stirring tank was changed to that shown in FIG.
A toner 84 shown in Table 4 was obtained in the same manner except that classification was not performed in a liquid using a centrifuge.

(Toner Production Example 7: Example of a pulverization method) A toner raw material composed of 100 kg of a styrene-n-butyl acrylate copolymer resin, 10 kg of carbon black, and 4 parts by mass of polypropylene was premixed with a Henschel mixer, and then twin-screw extruder , And coarsely pulverized with a hammer mill, pulverized with a jet pulverizer, and dispersed in a hot air flow of a spray drier (200 to 300 ° C.).
For 0.05 seconds) to obtain particles whose shape was adjusted. These particles were repeatedly classified by an air classifier until the target particle size distribution was obtained. 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 obtain a toner by a pulverization method.

In this way, the shape and the variation coefficient of the shape factor were controlled, and further, the variation coefficient of the particle size and the particle size distribution were adjusted to obtain toners 85 to 88 shown in Table 3.

[0168]

[Table 3]

[0169]

[Table 4]

Evaluation 1. Evaluation of photoconductor cleaning in high-speed printer The evaluation was made by Konica's printer “Sitios Ko”.
Nica 7075 "was used to output 2 million sheets.
The photoreceptor was a laminated organic photoreceptor, which was used as it was.

(Production of Developer) A developer for evaluation was produced by mixing each of the toners 1 to 88 with a 65 μm ferrite carrier coated with a silicone resin at a ratio of toner / carrier = 50 g / 950 g. did.

(Evaluation Method) (1) Presence or Absence of Occurrence of Cleaning Failure The image after 2,000,000 sheets was observed, and it was confirmed whether or not there was a stain on the background portion due to slipping through the cleaning and an image defect due to filming. (2) Amount of Wear of Rubber Blade The wear width of the blade after 2 million sheets from the first sheet was measured with a laser microscope. (3) Amount of wear of cleaning brush (cleaning member) A brush wear width after 2 million sheets from the first sheet was measured with a laser microscope.

Specifically, the length of the brush leg is set to 30
The length was measured and the average value was evaluated. (4) Line Width The line width of a line image corresponding to a 2-dot line image signal was measured by a print evaluation system “RT2000” (manufactured by Yarman).

The line width of the first formed image and 200
If any of the line widths of the 10,000th formed image is 200 μm or less and the change in the line width is less than 10 μm, it can be said that fine line reproducibility is not a problem. (5) Image Unevenness A halftone image having an image density of 0.5 was formed on the entire surface of the transfer material, and evaluated visually.

When there was no density unevenness synchronized with the rotation of the photosensitive member, "none" was used. (6) Black streaks A white background image was formed on the transfer material, and the presence or absence was visually determined. (7) Fog A white background image was formed on the transfer material, and the presence or absence was visually determined.

[0176]

[Table 5]

[0177]

[Table 6]

It can be seen that all the examples in the present invention show better characteristics than the comparative example. 2. Evaluation of cleaning of intermediate transfer body in color printer
An image was formed using a combination of the toners shown in Table 7 and evaluated.

For the evaluation, the image forming apparatus shown in FIG. 13 was used. However, no black toner was used.

Under the above conditions, 500,000 sheets of images were formed, and various evaluations were performed on the image formed on the first sheet and the image formed on the 500,000 sheet.

(Evaluation Method) (1) Presence or Absence of Occurrence of Cleaning Failure The image after 500,000 sheets was observed, and it was confirmed whether or not there was any stain on the background portion due to cleaning slippage and an image defect due to filming. (2) Amount of wear of rubber blade The wear width of the blade after 500,000 sheets from the first sheet was measured with a laser microscope. (3) Cleaning Brush (Cleaning Member) Wear Amount The brush wear width after 500,000 brushes from the first brush was measured with a laser microscope.

The length of each of the bristle legs of the brush was measured for 30 pieces, and the change in the average value was evaluated. (4) Line Width The line width of a line image corresponding to a 2-dot line image signal was measured by a print evaluation system “RT2000” (manufactured by Yarman).

If both the line width of the first formed image and the line width of the 500,000th formed image are 200 μm or less and the change in the line width is less than 10 μm,
It can be said that fine line reproducibility is not a problem. (5) Image Unevenness A halftone image having an image density of 0.5 was formed on the entire surface of the transfer material, and evaluated visually.

A sample having no density unevenness synchronized with the rotation of the photosensitive member was designated as "none". (6) Black streaks A white background image was formed on the transfer material, and the presence or absence was visually determined. (7) Fog A white background image was formed on the transfer material, and the presence or absence was visually determined.

[0185]

[Table 7]

It can be seen that all the examples in the present invention show better characteristics than the comparative example.

[0187]

According to the present invention, in the development of an image forming method and an image forming apparatus capable of obtaining a high-quality and stable copy image over a long period of time, image unevenness, black stripes,
It is possible to provide an electrostatic latent image developing toner which does not cause fogging and has extremely excellent cleaning performance, and an image forming method and an image forming apparatus using the same.

[Brief description of the drawings]

FIG. 1 is a perspective view of an example of a stirring tank provided with a conventional stirring blade.

FIG. 2 is a perspective view of an example of a stirring tank provided with stirring blades.

FIG. 3 is a top sectional view of FIG. 2;

FIG. 4 is a schematic diagram of a shape of a stirring blade.

FIG. 5 is a perspective view of an example of a stirring tank provided with stirring blades.

FIG. 6 is a perspective view of an example of a stirring tank provided with stirring blades.

FIG. 7 is a perspective view of an example of a stirring tank provided with stirring blades.

FIG. 8 is a perspective view of an example of a stirring tank provided with stirring blades.

FIG. 9 is a perspective view of an example of a stirring tank provided with stirring blades.

FIG. 10 is a schematic diagram illustrating toner particles without corners.

FIG. 11 is a schematic configuration diagram illustrating image formation according to the present invention.

FIG. 12 is a schematic configuration diagram of a cleaning device using an elastic rubber blade according to the present invention.

FIG. 13 is a schematic configuration diagram illustrating image formation according to the present invention.

FIG. 14 is a schematic diagram of a fixing device used in the image forming method according to the present invention.

[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 Pa, Pb, Pc, Pd Image forming unit 1a, 1b, 1c, 1d Photosensitive drum 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 13a, 13b, 13c, 13d Separation / discharge discharger 17 Fixing device 18 Intermediate transfer member 22 Cleaning device (cleaning device) 221 Rubber blade 222 Brush roller 24 Fixed and supported low heat capacity linear heating member 28 Film 29 Drive roller 30 Follower roller 35 Pressure roller S Transfer material

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 21/10 G03G 21/00 314 318 (72) Inventor Hiroshi Yamazaki 2970 Ishikawacho, Hachioji-shi, Tokyo Konica shares. F term in the company (reference) 2H005 AA15 AB04 AB06 AB09 EA05 EA10 2H030 AB02 AD01 AD03 AD04 BB42 2H034 AA06 BA01 BD03 BD04 BF02 BF03 BF05

Claims (51)

[Claims] 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 onto a transfer material. Then, a brush-like cleaning is performed on the photoreceptor. In an image forming method in which a step of cleaning and removing residual toner by a member and a rubber blade is repeated, the toner has a shape coefficient variation coefficient of 16% or less and a number variation coefficient in a number particle size distribution of 27% or less. Characteristic image forming method. 2. The image forming method according to claim 1, wherein the toner has 65% by number or more of toner particles having a shape factor in a range of 1.0 to 1.6. 3. The image forming method according to claim 1, wherein the toner has 65% by number or more of toner particles having a shape factor in a range of 1.2 to 1.6. 4. The image forming method according to claim 1, wherein the toner has 50% by number or more of toner particles having no corners. 5. The image forming method according to claim 1, wherein the number average particle diameter of the toner is 3 to 8 μm. 6. When the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.23.
In the histogram showing the number-based particle size distribution divided into a plurality of classes at intervals, the relative frequency (m1) of the toner particles included in the most frequent class and the toner particles included in the class having the second highest frequency after the most frequent class The sum (M) of the relative frequency (m2) of the first and the second is not less than 70%.
6. The image forming method according to any one of 5. 7. The image forming method according to claim 1, wherein the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 8. The image forming method according to claim 1, wherein the toner is formed by associating at least resin particles in an aqueous medium. 9. A brush-like cleaning of the photoreceptor after transferring a toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on the photoreceptor with a developer onto a transfer material. In an image forming method in which a step of cleaning and removing residual toner by a member and a rubber blade is repeated, the toner is such that toner particles having no corners are 50% by number or more and a number variation coefficient in a number particle size distribution is 27% or less. An image forming method comprising: 10. A toner having a shape factor of 1.0 to 1.6.
10. The image forming method according to claim 9, wherein the number of toner particles in the range is 65% by number or more. 11. The toner having a shape factor of 1.2 to 1.6.
The image forming method according to claim 9, wherein the number of toner particles in the range is 65% by number or more. 12. The image forming method according to claim 9, wherein the number average particle diameter of the toner is 3 to 8 μm. 13. When the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.2.
In the histogram showing the number-based particle size distribution divided into a plurality of classes at three intervals, the relative frequency (m1) of the toner particles included in the most frequent class and the toner included in the class having the second highest frequency after the most frequent class The sum (M) of the relative frequency (m2) of the particles is 70% or more.
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 is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 15. The toner according to claim 9, wherein the toner is formed by associating at least resin particles in an aqueous medium.
The image forming method according to claim 1. 16. A brush-like cleaning of the photoreceptor after the electrostatic latent image formed by performing charging and image exposure on the photoreceptor is developed with a developer, and the formed toner image is transferred onto a transfer material. In an image forming method for repeating a step of cleaning and removing residual toner by a member and a rubber blade, the toner includes:
6 toner particles having a shape factor in the range of 1.2 to 1.6
An image forming method, wherein the number is 5% by number or more and the variation coefficient of the shape factor is 16% or less. 17. The method according to claim 17, wherein the toner has no corner toner particles.
17. The image forming method according to claim 16, wherein the number is at least several percent. 18. The image forming method according to claim 16, wherein the number average particle diameter of the toner is 3 to 8 μm. 19. When the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.2.
In the histogram showing the number-based particle size distribution divided into a plurality of classes at three intervals, the relative frequency (m1) of the toner particles included in the most frequent class and the toner included in the class having the second highest frequency after the most frequent class The sum (M) of the relative frequency (m2) of the particles is 70% or more.
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 is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 21. The toner according to claim 16, wherein the toner has at least resin particles associated in an aqueous medium.
0. The image forming method according to any one of 0. 22. An image forming method according to claim 1, wherein
An image forming apparatus comprising the steps of cleaning, forming an electrostatic latent image, developing, transferring, and fixing. 23. An image forming method according to claim 9,
An image forming apparatus comprising the steps of cleaning, forming an electrostatic latent image, developing, transferring, and fixing. 24. 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 claim 16. 25. A color toner image obtained by visualizing an electrostatic latent image formed on a photoreceptor is superimposed on an intermediate transfer member, and then transferred from the intermediate transfer member to a transfer material to form an image. In the image forming apparatus, a photoreceptor that carries a color toner image visualized from an electrostatic latent image, an intermediate transfer body on which the color toner image on the photoreceptor is overlaid and rotated and moves, and A cleaning blade for scraping off the deposits adhering to the intermediate transfer body, and a brush disposed upstream of the cleaning blade with respect to the rotation direction of the intermediate transfer body for rotating and scraping off the deposits adhering to the intermediate transfer body In an image forming method including a step of cleaning and removing residual toner by providing a roller, the toner has a shape coefficient variation coefficient of 16% or less and a number variation coefficient in a number particle size distribution of 27% or less. An image forming method. 26. A toner having a shape factor of 1.0 to 1.6.
26. The image forming method according to claim 25, wherein the toner particles in the range are 65% by number or more. 27. A toner having a shape factor of 1.2 to 1.6.
26. The image forming method according to claim 25, wherein the toner particles in the range are 65% by number or more. 28. The method according to claim 28, wherein the toner has no corner particles.
The image forming method according to any one of claims 25 to 27, wherein the number is not less than a number%. 29. The image forming method according to claim 25, wherein the number average particle diameter of the toner is 3 to 8 μm. 30. Assuming that the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.2.
In the histogram showing the number-based particle size distribution divided into a plurality of classes at three intervals, the relative frequency (m1) of the toner particles included in the most frequent class and the toner included in the class having the second highest frequency after the most frequent class 26. The sum (M) of the relative frequency (m2) of the particles is 70% or more.
30. The image forming method according to any one of items 29 to 29. 31. The image forming method according to claim 25, wherein the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 32. The toner according to claim 25, wherein the toner is formed by associating at least resin particles in an aqueous medium.
2. The image forming method according to claim 1. 33. After a color toner image obtained by visualizing an electrostatic latent image formed on a photoreceptor is overlaid and transferred on an intermediate transfer member, an image is formed by transferring the color toner image from the intermediate transfer member to a transfer material. A photoreceptor carrying a color toner image visualized from an electrostatic latent image, an intermediate transfer member on which the color toner image on the photoreceptor is overlaid and rotated and moved, and A cleaning blade that scrapes off the deposits adhering to the top, and a cleaning blade that is disposed upstream of the cleaning blade with respect to the rotation direction of the intermediate transfer member and rotates and scrapes off the deposits adhering to the intermediate transfer member. In an image forming method including a brush roller and a process of repeatedly removing and removing residual toner, the toner has a toner particle having no corners of 50% by number or more and a number variation coefficient in a number particle size distribution of 27% or more. An image forming method, comprising: 34. The toner having a shape factor of 1.0 to 1.6.
34. The image forming method according to claim 33, wherein the toner particles in the range are 65% by number or more. 35. The toner having a shape factor of 1.2 to 1.6.
35. The image forming method according to claim 33, wherein the number of toner particles in the range is 65% by number or more. 36. The image forming method according to claim 33, wherein the number average particle diameter of the toner is 3 to 8 μm. 37. Assuming that the particle size of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.2.
In the histogram showing the number-based particle size distribution divided into a plurality of classes at three intervals, the relative frequency (m1) of the toner particles included in the most frequent class and the toner included in the class having the second highest frequency after the most frequent class The sum (M) of the relative frequency (m2) of the particles is 70% or more.
37. The image forming method according to any one of Items 36 to 36. 38. The image forming method according to claim 33, wherein the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 39. The toner according to claim 33, wherein the toner is formed by associating at least resin particles in an aqueous medium.
9. The image forming method according to any one of 8. 40. After a color toner image obtained by visualizing an electrostatic latent image formed on a photoreceptor is overlaid and transferred on an intermediate transfer member, an image is formed by transferring the image from the intermediate transfer member to a transfer material. A photoreceptor carrying a color toner image visualized from an electrostatic latent image, an intermediate transfer member on which the color toner image on the photoreceptor is overlaid and rotated and moved, and A cleaning blade that scrapes off the deposits adhering to the top, and a cleaning blade that is disposed upstream of the cleaning blade with respect to the rotation direction of the intermediate transfer member and rotates and scrapes off the deposits adhering to the intermediate transfer member. In an image forming method including a brush roller and repeating a step of cleaning and removing residual toner, the toner has a shape factor of 1.2.
An image forming method, wherein the number of toner particles in the range of 1.6 to 1.6 is at least 65% by number and the variation coefficient of the shape factor is 16% or less. 41. The method according to claim 41, wherein the toner has no corner toner particles.
41. The image forming method according to claim 40, wherein the number is not less than a number%. 42. The image forming method according to claim 40, wherein the number average particle diameter of the toner is 3 to 8 μm. 43. When the particle diameter of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is 0.2.
In the histogram showing the number-based particle size distribution divided into a plurality of classes at three intervals, the relative frequency (m1) of the toner particles included in the most frequent class and the toner included in the class having the second highest frequency after the most frequent class 41. The sum (M) of the relative frequency (m2) of the particles is 70% or more.
43. The image forming method according to any one of items 42 to 42. 44. The image forming method according to claim 40, wherein the toner is obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 45. The toner according to claim 40, wherein the toner has at least resin particles associated in an aqueous medium.
5. The image forming method according to any one of 4. 46. 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 claim 25. 47. 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 claim 33. 48. 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 claim 40. 49. A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer and transferring the toner image to a transfer material, and then on the photoreceptor or the intermediate transfer member. Is a toner for developing an electrostatic latent image used in an image forming method for repeating a process of cleaning and removing residual toner with a brush-like cleaning member and a rubber blade, wherein the toner has a shape coefficient variation coefficient of 16% or less. A toner for developing an electrostatic latent image, wherein a number variation coefficient in a particle size distribution is 27% or less. 50. A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer and transferring the formed toner image onto a transfer material, and then on the photoreceptor or the intermediate transfer member. Is a toner for developing an electrostatic latent image used in an image forming method in which a step of cleaning and removing residual toner is repeated by a brush-like cleaning member and a rubber blade, wherein the toner has 50% by number or more of toner particles having no corners, An electrostatic latent image developing toner, wherein the number variation coefficient in the number particle size distribution is 27% or less. 51. A toner image formed by developing an electrostatic latent image formed by performing charging and image exposure on a photoreceptor with a developer and transferring the formed toner image onto a transfer material, and then on the photoreceptor or the intermediate transfer member. In an electrostatic latent image developing toner used in an image forming method in which a step of cleaning and removing residual toner by a brush-like cleaning member and a rubber blade is repeated, the toner having a shape factor in a range of 1.2 to 1.6. Some toner particles are 65
A toner for developing an electrostatic latent image, wherein the toner has a number percent or more and a variation coefficient of a shape factor is 16% or less.