JP2003098927A - Image forming method and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming method and image forming device, which easily and effectively clear away toner particles, that is spherical toner, remaining on an image carrier after the step of transferring and effectively recover the toner particles. SOLUTION: The image forming method has the steps of forming a toner image on the image carrier, transferring the toner image to a transfer body, and removing residual toner on the image carrier after that. In the case the image forming method uses toner sphered during or after the production thereof, a clearing member is brought into contact with the surface of the image carrier or the surface of the transfer body at an angle to the vertical axis in its driven direction when toner remaining on the image carrier or transfer body is cleared away.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method and an image forming apparatus, and more particularly to an electrophotographic image forming method for a copying machine, a printer, a facsimile or the like using a dry two-component or one-component developer. The present invention also relates to an image forming apparatus and, more particularly, to an electrophotographic image forming method and an image forming apparatus that avoid cleaning failure after toner image transfer when spherical toner is used.

[0002]

2. Description of the Related Art In electrophotographic image formation of a copying machine, printer, facsimile, etc. using a dry two-component or one-component developer, it has been generally used as a charging and / or voltage applying member. There is a corona charging method. However, this corona charger has problems of deterioration of the photoconductor and environmental protection due to ozone generated during discharge, and as an alternative to this, electrophotography using a direct voltage application method is commercially available. . This is to apply a desired charge or voltage by applying a voltage to a low resistance member that is in contact with an electrophotographic photosensitive member or an intermediate transfer member. When such a voltage applying means is used in the transfer process, compared to the known corona charging method, the material to be transferred can be held more reliably, so that the transfer stability of the material to be transferred is high and the transfer bias is relatively low. Moreover, since it has a low capacity, it has the advantage that the device can be made compact and there is no problem of ozone generation, so it is beginning to be installed in many models.

Further, as a recent trend, instead of the irregular toner by the pulverizing and classifying method, polymerized toner by the suspension polymerization method, emulsion polymerization or dispersion polymerization method, or the spherical treatment by the hot air flow or fluidized granulation method is performed. These toners are being used, and are attracting attention as a toner having excellent fluidity and excellent image forming ability. However, a problem to be solved when using these spherical toners is poor cleaning property on the surface of the image carrier.

As a countermeasure against this, a brush is used in the cleaning process and the contact pressure of the cleaning blade is increased. In either case, mechanical stress on the photoconductor increases, and It becomes a factor that shortens the life of the body, and the blade is inverted,
There are problems such as fatal scratches on the photoconductor.

In JP-A-5-333757, a toner having a roundness of 0.85 or more, which is not high in sphericity, is used, and the surface average roughness of the photosensitive member is 0.1 to 2 μm.
It has been proposed to improve the poor cleaning property by roughening. However, with a toner having a low roundness, the precision of the image formed cannot be expected, and it is theoretically difficult to maintain the surface roughness of the photoreceptor over time, which is not practical. .

Further, in JP-A-9-96965, JP-A-9-114232, JP-A-9-274364, and JP-A-11-84878, there is a residue on the image carrier after the transfer step. There is a proposal to improve the cleaning property by reducing the charge amount of the residual toner by using various discharging means for the spherical toner. However, newly providing the above-mentioned charge eliminating means directly leads to an increase in the number of parts and an increase in manufacturing cost, and further, the residual toner is originally applied to the transfer target even if a large transfer bias is applied in the transfer step. It remains without being transferred,
It is estimated that the amount of charge stored therein is lower than that of the normally transferred toner, and therefore the amount of charge is changed only by the charge eliminating means, and the cleaning property is improved. Was what remained.

[0007]

SUMMARY OF THE INVENTION The present invention solves the conventional problems described above, and when spherical toner is used, the toner particles remaining on the image carrier after the transfer step are easily and efficiently cleaned. An object of the present invention is to provide an image forming method and an image forming apparatus that can be efficiently collected.

[0008]

In order to solve the above problems, the inventors of the present invention have conducted intensive studies by paying attention to the manner of contact of a cleaning member, and as a result, have completed the present invention. .

That is, according to the present invention, firstly, a toner image is formed on an image bearing member, the toner image is transferred to a transfer target member, and then the toner remaining on the image bearing member is removed. An image forming method having a step, in the case of using a spherical toner in the manufacturing step or the step after the manufacturing, when cleaning the toner remaining on the image bearing member or the transferred material, There is provided an image forming method, characterized in that a cleaning member to be brought into contact is brought into contact with the surface of the image bearing member or the surface of the transferred member at an angle with respect to a vertical axis in a driving direction.

According to the first invention, the following (1) to (1
The image forming method described in 0) is included. (1) As the image bearing member, the first image bearing member is an electrophotographic photosensitive member in the developing step, and the second image bearing member is an intermediate transfer member that temporarily holds a toner image in the transfer step. And an image forming method in which the intermediate transfer member is made of a belt-shaped conductive or semi-conductive elastic body. (2) An electrostatic latent image is formed on the first image bearing member by charging and exposure, and the electrostatic latent image is developed with toner to form a toner image. After the primary transfer onto the image bearing member, the secondary transfer from the second image bearing member to the transferred member, and then the removal of the toner remaining on the image bearing member, the second image bearing member Is a belt-shaped intermediate transfer member, and the cleaning member contacting the intermediate transfer member has an angle of at least 0.1 to 40 degrees with respect to a vertical axis of the driving direction of the intermediate transfer member. An image forming method for recovering the spherical toner remaining from the end of the body. (3) An image forming method in which the cleaning member is composed of a cleaning roller, and the cleaning roller rotates in a direction different from the moving direction of the image carrier. (4) The cleaning roller rotates in a direction different from the moving direction of the image carrier, and rotates at a linear velocity of 0.7 to 1.3 with respect to the linear velocity of the image carrier. An image forming method. (5) The cleaning roller is formed of an elastic body,
An image forming method in which the volume resistance of the elastic body is 10 ⁵ to 10 ¹³ Ωcm. (6) An image forming method including means for applying a voltage to the cleaning roller. (7) The ratio of the vertical adhesive force to the horizontal adhesive force in the adhesive force between the spherical toner and the transfer target, which is measured based on the powder adhesive force measuring method using the centrifugal separation method ( Horizontal adhesive force / vertical adhesive force) is 0.3
An image forming method using the following toner. (8) An image forming method in which a toner particle recovery mechanism is provided near the end of the intermediate transfer member as a means for recovering the spherical toner. (9) An image forming method in which the toner particle collecting mechanism is a mechanism for sucking an air stream containing toner particles. (10) The image forming method, wherein the mechanism for sucking the air flow containing the toner particles is a mechanism for electrostatically sucking.

According to the present invention, secondly, after the toner image is formed on the image bearing member and the toner image is transferred to the transfer target member, the toner remaining on the image bearing member is removed. An image forming apparatus having a step, in the case of using a spheroidized toner in the manufacturing step or the step after the manufacturing, when cleaning the toner remaining on the image bearing member or the transferred material, There is provided an image forming apparatus, wherein an abutting cleaning member is abutted at an angle with respect to a vertical axis of a driving direction of the surface of the image bearing member or the surface of the transferred material.

[0012]

In order to achieve the above object, the present inventors first observed in detail the state of the toner when a cleaning failure occurs. As a result, in the case of the irregular toner, the toner particles are repeatedly attached to and detached from the surface of the cleaning member without losing the kinetic energy after colliding with the cleaning member, and are easily separated because the separation from this member is also good. However, in the case of spherical toner, the particles only rotate in a state of being sandwiched between the cleaning member and the material to be cleaned at the collision position, and the particles are not detached from the cleaning member. It was found that cleaning failure occurs by flowing out from a slight gap generated between the member and the material to be cleaned.

That is, in the case of a toner having a specific shape, this phenomenon is that the kinetic energy originally possessed by the toner particles is converted into rotational energy without being stored after the collision with the cleaning member. It became clear that this was the cause of the problem. When this phenomenon is analyzed from the mechanical viewpoint as the adhesive force of the toner, the ratio of the adhesive force in the vertical direction and the adhesive force in the horizontal direction (horizontal adhesive force / vertical adhesive force) to the surface of the intermediate transfer body is 0.3 or less. In particular, the spherical toner has a tendency to be particularly remarkable. Therefore, as a result of studies by the present inventors, when the contact state of the cleaning member is devised, a part of the kinetic energy of the spherical toner is not converted as the rotational energy of the toner particles, but is directly used as the transfer energy to the toner recovery member. It was found that it could be used and the above problems would be solved dramatically.

Embodiments of the present invention will be described below with reference to the drawings. A simple example of the present invention is shown in FIG. FIG. 1 relates to a cleaning means provided on a belt-shaped intermediate transfer member.

As described above, by bringing the cleaning member into contact with the surface of the image bearing member or the surface of the transferred member at an angle (indicated by θ in the drawing) from the vertical axis of the driving direction, the spherical toner is in the middle of FIG. The toner gathers at the right end of the transfer belt and is collected here by the toner collecting means.

As shown in the enlarged view of the cleaning section shown in FIG. 2, this utilizes a peculiar phenomenon that when spherical toner collides with the cleaning member of this structure, the toner moves according to the inclination of the cleaning member. Is. The magnitude of θ depends on the member to be cleaned and the material of the toner, the linear velocity of the member to be cleaned, the contact pressure, etc., but as far as the present inventors have studied, the vertical axis of the driving direction of the intermediate transfer member is It has been found that it is preferably 0.1 to 40 degrees, and particularly preferably 1 to 30 degrees. This is because if the angle is too small, even if it is a spherical toner, the movement toward the end of the intermediate transfer body does not easily occur, and if it is too large, the cleaning process length is too long and the electronic transfer Since the photographic device becomes long, the upper limit is set within the range of common sense in design. In FIGS. 1 and 2, the right side of the drawing shows the inclination so that the right side is located downstream in the traveling direction of the intermediate transfer member. However, naturally, the inclination may be such that the left side becomes the downstream side. Can be arbitrarily selected according to the layout of each component constituting the.

Further, in the present invention, the case where a cleaning roller is used as the cleaning member is mentioned. It is desirable that the cleaning roller is in contact with the image carrier driving direction so as to rotate in the opposite direction, and its rotation speed is 0 .. when the moving speed of the image carrier is 1.
It is preferably in the range of 7 to 1.3. This is because if the number of revolutions is less than the above ratio, sufficient cleaning cannot be performed and cleaning failure is likely to occur from the beginning, and if it exceeds the above ratio, the stress on the cleaning roller and the image carrier is too large. This is because the deterioration of the member is promoted.

The cleaning roller may be provided with a mechanism for applying an electric field for collecting toner in order to improve its cleaning efficiency. Therefore, it is necessary for the roller to have semiconductivity, and the electric resistance range is 1
0 ⁵ to 10 ¹³ Ω · cm is desirable. This is because if the resistance value exceeds the above value, it becomes difficult to apply a sufficient electric field, and if the resistance value is less than the above resistance value, problems such as discharge tend to occur, which is not practical.

In the present invention, provision of a means for collecting the toner collected by the cleaning roller and its specific method are specified. The toner particles collected at the end portion of the intermediate transfer body may be directly dropped from the surface of the intermediate transfer body to be collected, but known toner collecting means can be used. It may be provided. Further, since the intermediate transfer member is driven at a high speed, as a method of collecting the toner particles without contacting the intermediate transfer member, a means for sucking and collecting the entire air flow containing the toner is used, or the toner is electrostatically collected. It is also possible to use a method of collecting by providing a voltage applying means for collecting.

Next, a method of measuring the powder adhesion force by centrifugation will be described. First, an apparatus for measuring the powder adhesion force in the direction perpendicular to the contacted film surface by the centrifugal separation method will be described. 3 to 5 are views showing a measuring cell and a centrifugal separator of the powder adhesion measuring device according to the present invention.

FIG. 3 is an explanatory view of a measuring cell of the powder adhesion measuring device. In FIG. 3, reference numeral 1 is a measuring cell, and the measuring cell 1 is a receiving substrate having a sample substrate 2 having a sample surface 2a to which powder is attached and an attaching surface 3a to which powder separated from the sample substrate 2 is attached. 3 and the sample surface 2 of the sample substrate 2
a and a spacer 4 provided between the attachment surface 3 a of the receiving substrate 3.

FIG. 4 is a partial sectional view of the centrifugal separator of the powder adhesion measuring device. In FIG. 4, reference numeral 5 is a centrifugal separator, and the centrifugal separator 5 includes a rotor 6 for rotating the measurement cell 1 and a holding member 7. The rotor 6 has a hole shape in a cross section perpendicular to the rotation center axis 9 of itself,
It has a sample setting part 8 for setting the holding member 7. The holding member 7 includes a rod-shaped portion 7a, a cell holding portion 7b provided in the rod-shaped portion 7a for holding the measurement cell 1, a hole portion 7c for pushing out the measurement cell 1 from the cell holding portion 7b, and the rod-shaped portion 7a as a sample setting portion. An installation fixing portion 7d for fixing to 8 is provided. The cell holding portion 7b is configured such that, when the measurement cell 1 is installed, the vertical direction of the measurement cell 1 is perpendicular to the rotation center axis 9 of the rotor. In addition, the sample substrate 2, the receiving substrate 3, the spacer 4, and the holding member 7 have strength capable of withstanding a large centrifugal force, and when installed on the rotor 6, a weight that allows the centrifugal separator to rotate up to the maximum rotation speed. It is necessary to use the following lightweight materials.

Next, an apparatus for measuring the powder adhesion force in the horizontal direction with respect to the contacted film surface will be described. This measurement is based on Japanese Patent Application Laid-Open No. 11-6421 filed by the applicant earlier.
The measurement is carried out according to the description in Japanese Patent Publication No. 2 etc. Figure 5
FIG. 3 is a partial cross-sectional view of a centrifugal separator that is an example of a horizontal powder adhesion measuring device. In FIG. 5, reference numeral 1 is a powder adhesion measuring device, and the powder adhesion measuring device 1 is provided with a sample substrate 2 having a sample surface 2a on which powder is adhered, and a centrifugal separator 3. The sample substrate 2 is composed of a member whose sample surface 2a is quadrangular.

The centrifugal separator 3 has a rotor 5 and a holding member 6. The rotor 5 is rotatably provided around the rotation shaft 4, and holds the sample substrate 2 inside such that the sample surface 2 a of the sample substrate 2 faces vertically upward and is perpendicular to the rotation shaft 4. Further, it has a recess having a shape corresponding to the shape of the holding member 6 and a sample setting portion 5a for supporting the holding member 6 in a fittable manner. The rotor 5 is an angle rotor in which the sample mounting portion 5 a is inclined with respect to the rotating shaft 4.

The holding member 6 includes a rod-shaped portion 7 and a substrate holding portion 8 which is provided on the rod-shaped portion 7 and holds the sample substrate 2. The rod-shaped portion 7 of the holding member 6 has an arrangement adjusting portion 7a provided at the tip, an arrangement fixing portion 7b that abuts on the inner peripheral surface of the sample setting portion 5a when fitted to the sample setting portion 5a of the rotor 5,
have. The substrate holding portion 8 of the holding member 6 includes a fixing member that fixes the sample substrate 2 to the holding member 6 and a guide 9. The guide 9 is the substrate holding portion 8
In order to prevent the sample surface 2a of the sample substrate 2 held in contact with the inner peripheral surface of the substrate holding portion 8, the inner peripheral surface portion of the substrate holding portion 8 corresponding to the peripheral portion of the sample surface 2a is provided. ing. A gap is formed between the guide 9 and the sample substrate 2. The fixing member includes a screw 10. After inserting the sample substrate 2 into the substrate holding portion 8 with the sample surface 2a facing vertically upward, the sample substrate 2 is screwed on.
Is fixed to the holding member 6 and held.

The sample substrate 2 has a substrate holding portion 8 of the holding member 6.
It is composed of a member having a shape in which the installation direction is constant when held by. The sample substrate 2 and the holding member 6 have strength enough to withstand the large centrifugal force of the rotor 5 of the centrifugal separator 3 and are composed of lightweight members that are not more than the weight that allows the rotor 5 to rotate at the maximum rotation speed. The arrangement adjusting portion 7a of the holding member 6 is composed of a convex portion having a protrusion capable of adjusting the orientation of the holding member with some jig or a concave portion having a concave shape corresponding to the tip of the driver. The arrangement fixing portion 7b of the holding member is made of an elastic member such as rubber.

The centrifugal separation adhesive force measuring method of the embodiment includes a substrate arranging step and an adhesive force deriving step. In the substrate arranging step, the operator uses the powder adhesion measuring device 1 shown in FIG. 1 so that the operator holds the sample substrate 2 with the sample surface 2a facing vertically upward, and the substrate holding portion of the holding member 6 is held. 8 and the sample substrate 2 is fixed to the holding member 6 by using the screw 10 so that the substrate holding portion 8 of the holding member 6 holds the sample substrate 2. The operator fits the holding member 6 into the sample setting portion 5a, rotates the arrangement adjusting portion 7a around the axis of the rod-shaped portion 7 of the holding member 6, and sets the arrangement fixing portion 7b in the inner peripheral surface of the sample setting portion 5a. The sample surface 2a of the sample substrate 2 held by the substrate holding portion 8 is directed vertically upward and is perpendicular to the rotation axis 4 of the rotor 5 by contacting the rotation axis 4 with the rotation axis 4. The orientation of the holding member 6 in the sample mounting portion 5a with respect to the vertical direction is adjusted and fixed. For this reason,
It is easy to arrange the holding member 6 in the rotor 5 so that the centrifugal force due to the rotation of the rotor 5 acts on the powder adhered to the sample surface 2a of the sample substrate 2 in the direction parallel to the sample surface 2a. be able to.

Further, since the sample substrate 2 is fixed to the holding member 6 with the screw 10, the sample surface 2a of the sample substrate 2 faces vertically upward and is perpendicular to the rotation axis 4 of the rotor 5. It can be maintained easily.
In the step of deriving the adhesive force, the rotor 5 holding the sample substrate 2 inside is rotated about the rotation axis 4 to move the powder on the sample substrate 2 to obtain a particle size of the powder, From the specific gravity of the powder, the distance from the rotation axis 4 to the center position of the measurement region of the powder, and the rotation speed of the rotor 5, the adhesive force of the powder to the sample surface 2a can be obtained. Therefore, by applying a large centrifugal force to the sample substrate 2 using the rotor 5, it is possible to measure the adhesive force of the powder having a large adhesive force.

As a known report example, for example, JP-A-6-3
No. 08759, No. 7-152218, No. 7-152242, No. 7-152253
Japanese Patent Laid-Open No. 7-152304, Japanese Patent Laid-Open No. 7-1
In JP-A-75266, JP-A-8-328306, and JP-A-8-328341, the toner shape is limited by using the following function as the shape coefficient representing the sphericity of the spherical toner. SF1 = (X ² / A) × (π / 4) × 100 (1) SF2 = (P ² / A) × (1 / 4π) × 100 (2)

In the above, X represents the absolute maximum length of the developer on the image, P the peripheral length of the developer projected image, and A the area of the developer projected image. For example, SF1 in the above formula (1) is 10
Although the shape is quantified by the limitation such as 5 or more and less than 160, the findings obtained by the present inventors have revealed that
In the current situation where materials such as resins and external additives that make up the toner change, no matter how numerically the shape is limited, it may be possible for certain materials, but controlling the behavior of spherical toner itself. It turns out that I can't. For example,
In the case as shown in FIG. 6, there is a large difference in adhesive force between the two toners, but the difference between the two is hardly confirmed by the SF value. In other words, the numerical expression of the sphericity in the above equation is merely a factor physically showing the “roundness” of the toner particles without the limitation of the constituent materials, and this is formed by the electrophotographic method. It cannot be a factor that directly affects the quality and characteristics of the image to be processed, and even if the above-mentioned conditions are satisfied, it is not an essential problem solving and many exceptions are included.

Therefore, the inventors of the present invention measure and control the difference in the toner characteristics based on the spheroidization of the toner in the form of a physically recognized adsorption energy, which is the adhesive force between the toner particles and other members. The present invention has been completed after confirming that the above problems can be solved without exception. The ratio of the vertical and horizontal adhesion forces in the present invention is considered to indicate the dynamic friction coefficient that acts when individual toner particles adhere to the contact member. Therefore, the smaller the ratio (horizontal direction / vertical direction) of the adhesive force, the easier the toner particles move from the position in contact with the contact member, and the more easily the particles are in a fluidized state.
It is considered to be a numerical value that simply represents the shape of the toner particles.

Next, the toner used in the present invention will be described. As the spherical toner used in the present invention, known ones can be used, but as a method of producing particles defined by vertical and horizontal adhesive forces, those produced by a dispersion polymerization method or a suspension polymerization method are available. It is suitable.

Next, a method of measuring the non-electrostatic adhesion force of toner using the above apparatus will be described. First, a film-shaped photoconductor is prepared, processed according to the shape of the sample substrate 2, and attached to the sample substrate 2 with an adhesive. Next, the uncharged toner is naturally dropped and attached onto the photoconductor (sample surface 2a) attached to the sample substrate 2. Next, as shown in FIG. 3, the measurement cell 1 is configured using the sample substrate 2, the receiving substrate 3, and the spacer 4.

When the holding member 7 of the measuring cell 1 is installed on the sample installation portion 8 of the rotor 6, the sample substrate 2 is replaced by the receiving substrate 3
It is installed in the cell holding portion 7b of the holding member 7 so as to be between the rotation center axis 9 of the rotor 6 and the rotation center axis 9 of the rotor 6. The holding member 7 is installed on the sample installation portion 8 of the rotor 6 so that the vertical direction of the measurement cell 1 is perpendicular to the rotation center axis 9 of the rotor. The centrifugal separator 5 is operated to rotate the rotor 6 at a constant rotation speed.
The toner attached to the sample substrate 2 receives a centrifugal force according to the number of rotations. When the centrifugal force received by the toner is larger than the adhesive force between the toner and the sample surface 2a, the toner is separated from the sample surface 2a, Adhere to 3a.

The centrifugal force F received by the toner is obtained from the equation (3) using the weight m of the toner, the rotational speed f (rpm) of the rotor, and the distance r from the central axis of the rotor to the toner adhering surface of the sample substrate. To be F = m × r × (2πf / 60) ² (3) The toner weight m is calculated from the equation (2) using the true specific gravity ρ of the toner and the equivalent circle diameter d. m = (π / 6) × ρ × d ³ (4) From Equations (3) and (4), the centrifugal force F received by the toner is
It is obtained from the equation (5). ^{F = (π 3/5400)} × ρ × d 3 × r × f 2 (5)

After the centrifugal separation is completed, the holding member 7 is taken out from the sample setting portion 8 of the rotor 6, and the cell holding portion 7 of the holding member 7 is removed.
The measuring cell 1 is taken out from b. The receiving substrate 3 is exchanged, the measuring cell 1 is installed on the holding member 7, and the holding member 7 is placed on the rotor 6.
The rotor 6 is rotated at a higher rotation speed than the last time. The centrifugal force received by the toner becomes larger than that of the previous time, and the toner having a large adhesion force is separated from the sample surface 2a and adheres to the adhesion surface 3a.

By changing the set rotational speed of the centrifuge from a low rotational speed to a high rotational speed and performing the same operation, the sample surface 2a is adjusted according to the magnitude relationship between the centrifugal force and the adhesive force received at each rotational speed. The upper toner moves to the adhesion surface 3a. After the centrifugal separation is performed for all the set rotational speeds, the particle size of the toner adhering to the adhering surface 3a of the receiving substrate 3 at each rotational speed is measured to obtain the adhesive force of each toner by using the formula (5). be able to. The toner particle size and number are
The toner on the adhering surface 3a can be observed with an optical microscope, the image can be taken into a computer through a CCD camera, and the image processing software can be used.

Next, the dispersion-polymerized toner used in the present invention will be described. The resin particles A in the present invention are prepared by adding a polymer dispersant that dissolves in the hydrophilic organic liquid to the hydrophilic organic liquid, and dissolving the polymer dispersant in the hydrophilic liquid. Swollen in, or
It is produced by adding one or two or more vinyl monomers which are hardly dissolved and polymerizing.

The hydrophilic organic liquid that is a diluent for the monomers used in the formation of the seed particles and the growth reaction of the seed particles is methyl alcohol, ethyl alcohol, modified ethyl alcohol, isopropyl alcohol, n-butyl alcohol. , Isobutyl alcohol, t-butyl alcohol, s-butyl alcohol, t-amyl alcohol, 3
-Alcohols such as pentanol, octyl alcohol, benzyl alcohol, cyclohexanol, furfuryl alcohol, tetrahydrofurfuryl alcohol, ethylene glycol, glycerin, diethylene glycol, methyl cellosolve, cellosolve, isopropyl cellosolve, butyl cellosolve, ethylene glycol monomethyl ether, ethylene glycol Representative examples include ether alcohols such as monoethyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. These organic liquids can be used alone or as a mixture of two or more kinds.

By using an organic liquid other than alcohols and ether alcohols in combination with the above-mentioned alcohols and ether alcohols, under the condition that the organic liquid is not soluble in the produced polymer particles. By varying the SP value of the organic liquid to carry out the polymerization, it is possible to suppress the size of the produced particles, the coalescence of seed particles and the generation of new particles.

In this case, the organic liquid used in combination includes hydrocarbons such as hexane, octane, petroleum ethyl, cyclohexane, benzene, toluene and xylene, and halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene and tetrabromoethane. , Ethers such as ethyl ether, dimethyl glycol, silioxane, tetrahydrofuran, acetals such as methylal and diethyl acetal, acetone, methyl ethyl ketone, methyl isobutyl ketone, ketones such as cyclohexane, butyl formate, butyl acetate, ethyl propionate, cellosolve acetate Esters such as, formic acid, acetic acid, acids such as propionic acid, nitropropene, nitrobenzene, dimethylamine, monoethanolamine, pyridine, dimethyl sulfoxide, dimethy Sulfur such as formamide, nitrogen-containing organic compounds, other water is also included. The average particle size, particle size distribution, drying conditions, etc. of the polymer particles produced can be adjusted by changing the type and composition of the mixed solvent at the start of polymerization, during the polymerization, and at the end of the polymerization.

Suitable examples of the polymeric dispersant used in the production of seed particles or the production of grown particles include, for example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, croton. Acids, fumaric acid, acids such as maleic acid or maleic anhydride, acrylic monomers containing a hydroxyl group, for example, β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate.
Β-hydroxypropyl acrylate, β-methacrylic acid
Hydroxypropyl, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl acrylate, 3 methacrylic acid
-Chloro-2-hydroxypropyl, diethylene glycol monoacrylic acid ester, diethylene glycol monomethacrylic acid ester, glycerin monomethacrylic acid ester, glycerin monomethacrylic acid ester, N-methylol acrylamide, N-methylol methacrylamide, etc., with vinyl alcohol or vinyl alcohol Ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc., or esters of compounds containing a vinyl alcohol and a carboxyl group, such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, Diacetone acrylamide or methylol compounds thereof, acid chlorides such as acrylic acid chloride and methacrylic acid chloride, vinyl chloride Pyridine, vinylpyrrolidone, vinylimidazole, homopolymers or copolymers such as those having a nitrogen atom or its heterocycle such as ethyleneimine, polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, Polyoxyethylene alkyl amides, polyoxypropylene alkyl amides, polyoxyethylene nonyl phenyl ethers, polyoxyethylene lauryl phenyl ethers, polyoxyethylene stearyl phenyl esters, polyoxyethylene nonyl phenyl esters such as polyoxyethylene-based, methyl cellulose, hydroxyethyl cellulose , Cellulose such as hydroxypropyl cellulose or the above hydrophilic monomer and styrene, α-methylstyrene, vinyltoluene Having a benzene nucleus such as amine or a derivative thereof or acrylonitrile,
Copolymers with acrylic acid or methacrylic acid derivatives such as methacrylonitrile and acrylamide, as well as cross-linkable monomers such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, allyl methacrylate, divinylbenzene, etc. It is possible.

These polymer dispersants are appropriately selected depending on the hydrophilic organic liquid used, the seeds of the intended polymer particles and the production of seed particles or grown particles. Since the coalescence is mainly sterically prevented, a polymer having a high affinity for the polymer particle surface and an adsorptive property and a high affinity for the hydrophilic organic liquid and a high solubility is selected. Also,
In order to increase the repulsion between the particles in a three-dimensional manner, a molecular chain having a certain length, preferably a molecular weight of 10,000 or more is selected. However, when the molecular weight is too high, the viscosity of the liquid is remarkably increased, the operability and the stirring property are deteriorated, and the precipitation probability of the produced polymer on the particle surface is varied, so that caution is required. It is also effective for stabilization that a part of the above-mentioned polymer dispersant monomer is allowed to coexist with the monomer constituting the intended polymer particles.

Further, together with these polymer dispersants, metals such as cobalt, iron, nickel, aluminum, copper, tin, lead and magnesium or alloys thereof (particularly, those having a particle size of 1 μm or less), iron oxide, oxidation Fine powder of inorganic compounds of oxides of copper, nickel oxide, zinc oxide, titanium oxide, silicon oxide, etc., anionic surfactants such as higher alcohol sulfate ester salts, alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, etc. , Alkylamine salts, aminoalcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts,
Pyridinium salts, alkylisoquinolinium salts, quaternary ammonium salt type cationic surfactants such as benzethonium chloride, nonionic surfactants such as fatty acid amide derivatives and polyhydric alcohol derivatives, such as alanine type [eg, dodecyldiene (Aminoethyl) glycine, di (octylaminoethyl) glycine] and other amino acid type or betaine type amphoteric surfactants can be used together to further improve the stability and particle size distribution of the produced polymer particles. it can.

Generally, the amount of the polymer dispersant used in the production of the seed particles varies depending on the kind of the polymerizable monomer for forming the intended polymer particles, but is 0.1 with respect to the hydrophilic organic liquid.
10 to 10% by weight, preferably 1 to 5% by weight. When the concentration of the polymer dispersion stabilizer is low, the resulting polymer particles have a relatively large particle size, and when the concentration is high,
Although a small particle size is obtained, even if it is used in an amount exceeding 10% by weight, the effect of reducing the particle size is small.

The vinyl monomer is one that can be dissolved in a hydrophilic organic liquid, such as styrene or o.
-Methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylethylene,
2,4-dimethylstyrene, pn-butylstyrene,
p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-phenyl styrene,
Styrenes such as p-chlorostyrene and 3,4-dichlorostyrene, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, acrylic Lauryl acid, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-chloromethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, methacrylic acid Isobutyl, n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-methacrylic acid
Α-Methyl fatty acid monocarboxylic acid esters such as ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, acrylonitrile, methacrylonitrile, acrylic acid or methacrylic acid derivatives such as acrylamide, vinyl chloride. , Vinylidene chloride, vinyl bromide, vinyl fluoride, and other vinyl halides, etc., and mixtures thereof alone or with each other, and with a monomer containing 50% by weight or more of these and copolymerizable with them, Can be mentioned.

The above-mentioned polymer in the present invention may be polymerized in the presence of a so-called cross-linking agent having two or more polymerizable double bonds in order to enhance the offset resistance. . As the crosslinking agent preferably used,
Aromatic divinyl compounds which are divinylbenzene, divinylnaphthalene and their derivatives, and others, ethylene glycol dimethacrylate, diethylene glycol methacrylate, triethylene glycol methacrylate,
Trimethylolpropane triacrylate, allyl methacrylate, tert-butylaminoethyl methacrylate, tetraethylene glycol dimethacrylate,
1,3-butanediol dimethacrylate and other diethylenic carboxylic acid esters, N, N-divinylaniline,
Examples thereof include all divinyl compounds such as divinyl ether, divinyl sulfide and divinyl sulfone and compounds having three or more vinyl groups, and these may be used alone or in a mixture.

When the growth polymerization reaction is subsequently carried out using the seed particles thus crosslinked, the inside of the growing polymer particles is crosslinked. On the other hand, when the vinyl monomer solution used for the growth reaction contains the above-mentioned cross-linking agent, a polymer whose particle surface is hardened can be obtained.

For the purpose of adjusting the average molecular weight,
Examples of compounds in which a compound having a large chain transfer constant is allowed to coexist are a low molecular compound having a mercapto group, carbon tetrachloride, carbon tetrabromide, and the like.

Further, as the polymerization initiator of the above monomer,
For example, 2,2'-azobisisobutyronitrile, 2,
Azo-based polymerization initiators such as 2′-azobis (2,4-dimethylvaleronitrile), peroxide-based polymerization initiators such as lauryl peroxide, benzoyl peroxide, t-butyl peroctoate, potassium persulfate, etc. A persulfate-based polymerization initiator, a system in which sodium thiosulfate, an amine and the like are used in combination, and the like are used. The concentration of the polymerization initiator is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the vinyl monomer.

The polymerization conditions for obtaining the seed particles are as follows: the concentration of the polymer dispersant in the hydrophilic organic liquid, the concentration of the vinyl monomer, and the blending ratio, in accordance with the target average particle size of the polymer particles and the target particle size distribution. Determined by Generally, if the average particle size of the particles is reduced, the concentration of the polymer dispersant is set high, and if the average particle size is increased, the concentration of the polymer dispersant is set low. On the other hand, if the particle size distribution is to be made extremely sharp, the vinyl monomer concentration is set low, and if the distribution is relatively wide, the vinyl monomer concentration is set high.

The particles are produced by completely dissolving the polymer dispersion stabilizer in the hydrophilic organic liquid, and then using one or more vinyl monomers, a polymerization initiator, other inorganic fine powder, an interface, if necessary. 30-300 by adding activator, dye, pigment, etc.
The stirring speed of the polymerization initiator used is preferably as slow as possible, and the stirring speed of the turbine is more than that of the paddle type. Polymerization is carried out by heating at the corresponding temperature. Since the temperature at the initial stage of polymerization has a great influence on the type of particles produced, it is desirable to raise the temperature to the polymerization temperature after adding the monomer, and dissolve the polymerization initiator in a small amount of solvent before charging. At the time of polymerization, it is necessary to sufficiently expel oxygen in the air in the reaction vessel with an inert gas such as nitrogen gas or argon gas. If the oxygen purge is insufficient, fine particles are likely to be generated.

To carry out the polymerization in a high polymerization rate range, 5 to 40
Although it takes a long time for the polymerization, the polymerization rate can be increased by stopping the polymerization in a desired particle size and particle size distribution state, by sequentially adding a polymerization initiator, and by carrying out the reaction under high pressure. You can speed it up. After completion of the polymerization, it may be used as it is in the dyeing step, or after removing unnecessary fine particles, residual monomer, polymer dispersion stabilizer, etc. by operations such as sedimentation, centrifugation, decantation, etc., the polymer You may collect as a slurry and dye it. However, when the dispersion stabilizer is not removed, the stability of dyeing is high and unnecessary aggregation is suppressed.

Dyeing in the present invention will be described below. The resin particles A are dispersed in an organic solvent that does not dissolve the resin particles A, and the dye is dissolved in the solvent before or after this, and the dye is permeated into the resin particles A for coloring, and then the organic solvent is added. In the method for producing a dyed toner by removing the dye, the liquid solubility (D
1) and the solubility (D2) of the dye in the resin of the resin particles A is (D1) / (D2) ≦ 0.5. This makes it possible to efficiently manufacture a toner in which the dye penetrates (diffuses) to the deep portion of the resin particle A. Solubility in the present invention is defined as measured at a temperature of 25 ° C.

The solubility of the dye in the resin has exactly the same definition as the solubility of the dye in the solvent, and means the maximum amount of the dye that can be contained in the resin in a compatible state. Observation of the dissolved state or the deposited state of the dye can be easily performed by using a microscope. In order to know the solubility of the dye in the resin, an indirect observation method may be used instead of the above direct observation method. In this method, a liquid having a solubility coefficient similar to that of the resin, that is, a solvent that dissolves the resin well may be used, and the solubility of the dye in this solvent may be determined as the solubility in the resin.

As the dye used for coloring, the ratio (D1) / (D2) of the dye to the resin constituting the resin particles is determined from the solubility (D1) of the dye in the organic solvent used as described above.
Should be 0.5 or less. Furthermore, (D1) / (D
2) is preferably 0.2 or less. The dye is not particularly limited as long as it satisfies the above-mentioned solubility characteristics, but a water-soluble dye such as a cationic dye or an anionic dye may have a large environmental change, and the electric resistance of the toner becomes low, and the transfer rate decreases. There is a risk that
Disperse dyes and oil-soluble dyes are preferably used, and oil-soluble dyes are particularly preferable. Further, several kinds of dyes can be used in combination depending on the desired color tone. The ratio (weight) of the dye to be dyed and the resin particles is arbitrarily selected according to the degree of coloring,
Usually, it is preferable to use 1 to 50 parts by weight of the dye per 1 part by weight of the resin particles.

For example, when an alcohol having a high SP value such as methanol or ethanol is used as the dyeing solvent and a styrene-acrylic resin having an SP value of about 9 is used as the resin particles, the dye that can be used is For example, C.I. I.
SOLVENT YELLOW (6, 9, 17, 3
1, 35, 1, 102, 103, 105), C.I. I. S
OLVENT ORANGE (2,7,13,14,6
6), C.I. I. SOLVENT RED (5,16,
17, 18, 19, 22, 23, 143, 145, 14
6, 149, 150, 151, 157, 158), C.I.
I. SOLVENT VIOLET (31, 32, 3
3, 37), C.I. I. SOLVENTBLUE (2
2,63,78,83-86,91,94,95,10
4), C.I. I. SOLVENT GREEN (24,
25), C.I. I. SOLVENT BROWN (3,
9) and the like.

Among commercially available dyes, for example, Aizen SOT dyes Yellow-1,3,4, Ora manufactured by Hodogaya Chemical Co., Ltd.
nge-1, 2, 3, Scarlet-1, Red-
1, 2, 3, Brown-2, Blue-1, 2, Vi
olet-1, Green-1, 2, 3, Black-
1,4,6,8, Sudan dye from BASF, Ye
low-140, 150, Orange-220, R
ed-290, 380, 460, Blue-670, Mitsubishi Kasei's dialresin, Yellow-3G, F,
H2G, HG, HC, HL, Orange-HS, G,
Red-GG, S, HS, A, K, H5B, Violet
t-D, Blue-J, G, N, K, P, H3G, 4
G, Green-C, Brown-A, oil color manufactured by Orient Chemical Co., Yellow-3G, GG-S,
# 105, Orange-PS, PR, # 201, Sc
arlet- # 308, Red-5B, Brown-G
R, # 416, Green-BG, # 502, Blue
-BOS, HN, Black-HBB, # 803, E
E, EX, Sumiplast made by Sumitomo Chemical Co., Ltd., Blue G
P, OR, red FB, 3B, yellow FL7G, G
C, Nippon Kayaku's Kayaron, polyester black E
X-SH3, Kayaset Red-B blue A-2R and the like can be used. The dye is not limited to the above examples because it is appropriately selected depending on the combination of the resin particles and the solvent used for dyeing.

The organic solvent used for dyeing the resin particles with the dye is one in which the resin particles used do not dissolve or causes some swelling, specifically, a difference in solubility parameter (SP value). 1.0 or more, preferably 2.
Zero or more are used. For example, for styrene-acrylic resin particles, n-hexane, n-heptane or the like having a low SP value is used as an alcohol type such as methanol, ethanol or n-propanol having a high SP value. SP
If the difference in value is too large, the wettability with respect to the resin particles deteriorates, and good dispersion of the resin particles cannot be obtained,
The optimum SP value difference is preferably 2-5.

In the dyeing step, it is preferable to disperse the resin particles in an organic solvent in which the dye is dissolved, then keep the liquid temperature below the glass transition temperature of the resin particles and stir. This makes it possible to dye the resin particles while preventing them from aggregating. The stirring method is a commercially available stirrer, for example,
It may be stirred using a homomixer, a magnetic stirrer, or the like. Further, the dye may be directly added to the slurry obtained at the end of the polymerization by dispersion polymerization or the like, that is, the dispersion liquid in which the polymerized resin particles are dispersed in the organic solvent, and the mixture may be heated and stirred under the above conditions. If the heating temperature exceeds the glass transition temperature, fusion of the resin particles will occur. The method of drying the slurry after dyeing is not particularly limited, but may be dried under reduced pressure after filtration or directly under reduced pressure without filtering. In the present invention, the colored particles obtained by air-drying or vacuum-drying after filtering, there is almost no aggregation,
It can be reproduced without substantially impairing the particle size distribution of the introduced resin particles.

Next, the suspension polymerization toner will be described. The polymerizable monomer used in suspension polymerization is a monomer having a vinyl group, and specifically, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, Examples thereof include styrene such as butyl styrene and octyl styrene and derivatives thereof, and among them, a styrene monomer is most preferable. Other vinyl monomers include ethylenically unsaturated monoolefins such as propylene, butylene and isobutylene, vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide and vinyl fluoride, vinyl acetate and propionic acid. vinyl,
Vinyl esters such as vinyl benzoate and vinyl butyrate,
Methyl acrylate, ethyl acrylate, acrylic acid n-
Butyl, isobutyl acrylate, propyl acrylate,
-N-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate,
2-chloroethyl acrylate, phenyl acrylate,
α-chloromethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, methacrylic acid Α-Methylene aliphatic monocarboxylic acid esters such as phenyl acid and diethylaminoethyl methacrylate, acrylonitrile, methacrylonitrile, acrylic acid or methacrylic acid derivatives such as acrylamide, vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether, vinyl methyl ketone , Vinyl hexyl ketone, methyl isopropenyl ketone and other vinyl ketones, N-vinyl pyrrole, N-vinyl carbazole, N
-N- such as vinylindole and N-vinylpyrrolidone
Examples thereof include vinyl compounds and vinylnaphthalene, and these monomers can be used alone or in combination.

In order to form a crosslinked polymer in the monomer composition, suspension polymerization may be carried out in the presence of the following crosslinking agent. As this cross-linking agent, divinylbenzene,
Divinylnaphthalene, polyethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,6-hexane glycol dimethacrylate, neopentyl glycol diacrylate, dipropylene glycol dimethacrylate, polypropylene glycol Dimethacrylate, 2,2'-bis (4-methacryloxydiethoxyphenyl) propane, 2,2'-bis (4-acryloxydiethoxyphenyl) propane, trimethylolpropane trimethacrylate, trimethylolmethane tetraacrylate,
Examples include dibromoneopentyl glycol dimethacrylate and diallyl phthalate.

When the amount of the cross-linking agent used is too large, the toner is less likely to be melted by heat, resulting in poor heat fixing property and heat pressure fixing property. Further, when the amount of the crosslinking agent used is too small, properties such as blocking resistance and durability required as a toner are deteriorated, and at the time of heat roll fixing, a part of the toner does not completely adhere to the paper and is adhered to the roll surface. Cold offset occurs in which the toner adheres and is transferred to the next paper. Therefore, the amount of the crosslinking agent to be used is 0.001 to 15 parts by weight, preferably 0.1 to 15 parts by weight, based on 100 parts by weight of the polymerizable monomer.
10 parts by weight.

Further, a releasing agent may be contained in the polymerization composition in order to prevent offset of the obtained toner. As the release agent, low molecular weight polyolefins such as polyethylene and polypropylene are preferable. This low molecular weight olefin polymer is preferably dispersed in a polymerizable monomer together with a colorant. The releasing agent is preferably used in an amount of 1 to 15 parts by weight with respect to 100 parts by weight of the polymerizable monomer. When the amount of the release agent used is less than 1 part by weight, the obtained toner does not have a sufficient release effect and is easily offset on the roller. On the other hand, if the amount used exceeds 15 parts by weight, the release agent will be spent from the toner on the frictional charge imparting member, and the fluidity of the toner will be extremely deteriorated.

As the colorant contained in the monomer, conventionally known dyes and carbon black, and pigments such as grafted carbon black obtained by coating the surface of carbon black with a resin can be used. Other colorants include lamp black, iron black, ultramarine blue, nigrosine dye, aniline blue, phthalocyanine green, Hansa yellow G, rhodamine 6G, lake, chalco oil blue, chrome yellow, quinacridone, benzidine yellow, rose bengal, triallyl. There are dyes and pigments such as methane dyes, monoazo dyes, and disazo dyes. In addition,
These colorants can be used in an amount of 0.1 to 30 parts by weight based on 100 parts by weight of the polymerizable monomer.

The following can be used as the dispersion stabilizer. That is, water-soluble polymers such as polyvinyl alcohol, starch, methyl cellulose, carboxymethyl cellulose, hydroxymethyl cellulose, sodium polyacrylate, sodium polymethacrylate, barium sulfate, calcium sulfate, barium carbonate, magnesium carbonate, calcium phosphate, talc, clay, diatomaceous earth. , Metal oxide powder and the like are used. These are 0.1 against water
It is preferably used in the range of 10 to 10% by weight.

In the present invention, the polymerization initiator may be added to the dispersion liquid containing the monomer composition after granulation, but the polymerization initiator is uniformly applied to the individual monomer composition particles. From the point of view, it is desirable that the monomer composition be contained in the monomer composition before granulation. Examples of such a polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile) and 2,2 ′.
-Azobisisobutyronitrile, 1,1'-azobis-
(Cyclohexane-1-carbonitrile), 2,2'-
Azo-based or diazo-based polymerization initiators such as azobis-4-methoxy-2,4-dimethylvaleronitrile and azobisbutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, isopropyl peroxide,
Examples thereof include peroxide-based polymerization initiators such as 2,4-dichlorolylbenzoyl peroxide and lauryl peroxide.

The toner of the present invention may be a magnetic toner containing a magnetic material. To obtain a magnetic toner, magnetic particles may be added to the monomer composition. Examples of the magnetic material that can be used in the present invention include powders of ferromagnetic metals such as iron, cobalt and nickel, and powders of alloys and compounds such as magnetite, hematite and ferrite. As the magnetic particles, those having a particle size of 0.05 to 5 μm, preferably 0.1 to 1 μm are used, but when producing a small particle size toner, magnetic particles having a particle size of 0.8 μm or less are used. It is desirable to do. The magnetic particles are preferably contained in 10 to 60 parts by weight in 100 parts by weight of the monomer composition.

Further, these magnetic particles may be treated with a surface treating agent such as a silane coupling agent or a titanium coupling agent, or an appropriate reactive resin. in this case,
Depending on the surface area of the magnetic particles or the density of hydroxyl groups present on the surface, it is usually 5 parts by weight or less, preferably 0.1 to 3 parts by weight of the surface treatment agent per 100 parts by weight of the magnetic particles, Sufficient dispersibility in the polymerizable monomer is obtained, and physical properties of the toner are not adversely affected.

[0070]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. All parts shown below are based on weight.

[Method for producing spherical toner] 40 parts by weight of styrene monomer, 20 parts by weight of carbon black MA100 (manufactured by Mitsubishi Kasei) and 0.5 parts by weight of 2,2'-azobisisobutyronitrile as a polymerization initiator. In addition, put in a 500 ml four-neck separable flask equipped with a three-one motor driven stirring blade, cooler, gas introduction tube, thermometer,
The mixture was stirred at room temperature for 30 minutes under a nitrogen stream, and oxygen in the flask was replaced with nitrogen. Then, in a hot water bath at 70 ° C for 6 hours,
The mixture was stirred at 60 rpm to obtain graft carbon black.

Then, the following mixture was mixed with a ball mill for 10 minutes.
Time dispersed. Styrene monomer 50 parts n-Butyl methacrylate 14.5 parts 1,3-Butanediol dimethacrylate 0.5 parts t-Butyl acrylamide sulfonic acid 3 parts Low molecular weight polyethylene (Mitsui Petrochemical Co., Ltd., Mitsui High Wax 210P) 2 parts 30 parts of the above-mentioned graft carbon black

To the resulting dispersion, 1 part by weight each of 2,2'-azobisisobutyronitrile and sodium nitrite were dissolved, and then added to 250 parts by weight of a 2% aqueous solution of polyvinyl alcohol. A TK homomixer manufactured by Kasei Co., Ltd. was stirred at 1,000 to 6,000 rpm for 10 minutes to obtain a suspension. This suspension was equipped with a three-one motor driven stirring blade, a cooler, a gas introduction pipe, and a thermometer.
The mixture was placed in a 0 ml four-neck separable flask and stirred at room temperature under a nitrogen stream, and oxygen in the flask was replaced with nitrogen. Then, in a hot water bath at 70 ° C for 5-8 hours, about 100r
Polymerization was completed by stirring at pm to prepare suspension-polymerized particles. 100 parts by weight of these particles are added to water / methanol = 1/1
Liquid mixture was redispersed to a solid content of 30% (weight _{ratio), H 4 N (CH 2} ) as a charge control agent ₅ CH = C (C
₂ F ₅ ) ₂ (3 parts by weight) was added, and the mixture was stirred, filtered and dried to obtain a toner.

The toner particles and silica fine particles were blended so that the amount of silica fine particles added was 0.5% by weight of the toner amount, and the mixture was stirred and mixed by a Henschel mixer to prepare an electrophotographic toner.

The electrophotographic toner obtained as described above is
A two-component developer was prepared by mixing with a carrier for a copying machine (Preter450 manufactured by Ricoh Co., Ltd.), stirring and blending so as to have a toner concentration of 5.0% by weight. After sufficiently mixing this toner and the above carrier, the charge amount of the toner was measured by the blow-off method, and the charge amount was −22.6 μC /
It was g. The charge amount after 1 minute is -18.8 μC /
It was g, and the rise of charging was very good.

[Measurement of Adhesive Force] Adhesive forces in the vertical and horizontal directions of the electrophotographic toners of Examples and Comparative Examples were measured by the above-mentioned method of measuring the adhesive force of particles by centrifugation. The photoconductor used for the measurement is Precor 450 manufactured by Ricoh.
An organic photoconductor film having the same structure as that of the above-mentioned photoreceptor was applied on a Mylar film on which Al was vapor deposited. The measurement results are shown in Tables 1 to 3. The equipment used for the measurement is as follows. Centrifuge: CP100α manufactured by Hitachi Koki Co., Ltd. ・ Maximum rotation speed: 100,000 rpm ・ Maximum acceleration: 800,000 × g ・ Angle rotor P100AT) Image processing device: Hyper700 manufactured by Interquest

[Actual Machine Test] Example 1 A copy machine of imaco color 4000 made by Ricoh was remodeled, and the cleaning roller for the intermediate transfer belt was brought into contact with the transfer belt in the counter direction with respect to the drive direction and the transfer belt drive speed. The cleaning roller at the front side of the apparatus is installed at an angle such that the end of the cleaning roller is at the downstream side of the end at the back side (see FIG. 1). The angle at this time was set to 5 degrees. The cleaning roller has a linear velocity of the intermediate transfer belt (300 mm / s)
The intermediate transfer belt was installed so as to come into contact with the intermediate transfer belt at a constant speed and in the opposite direction. In addition, DC is +30 for the cleaning roller.
An electric field of 0 to +500 V was applied. The transfer residual toner is provided with a mechanism for collecting the cleaning belt by applying a voltage from the front side of the apparatus and bringing the cleaning belt into contact with the end surface of the belt.

The above two-component developer was set in the above copying machine, and a pattern image was formed in a single color mode.
After repeating about once, the presence or absence of an abnormal image due to defective cleaning and the state of toner remaining on the image photoreceptor after the cleaning process were confirmed, and the results shown in Table 1 were obtained. Further, after that, a running test was performed by passing 10,000 sheets, and it was confirmed whether or not an abnormal image was generated due to the image evaluation by the same pattern image and the cleaning residue.
The results are shown in Table 1.

Example 2 The angle of the cleaning blade for the intermediate transfer belt installed in Example 1 was set to 10 with respect to the driving direction of the transfer belt.
The same method as in Example 1 was performed except that the temperature was set to 0.

Example 3 The angle of the cleaning blade for the intermediate transfer belt set in Example 1 was set to 30 with respect to the transfer belt driving direction.
The same method as in Example 1 was performed except that the temperature was set to 0.

Example 4 The angle of the cleaning blade for the intermediate transfer belt installed in Example 1 was set to 40 with respect to the transfer belt driving direction.
The same method as in Example 1 was performed except that the temperature was set to 0.

Example 5 The angle of the cleaning blade for the intermediate transfer belt set in Example 1 above was set to 1 degree with respect to the transfer belt driving direction, and a suction fan was provided in the toner collecting section, so The same method as in Example 1 was carried out except that a mechanism for collecting the toner sent to the end portion of the roller was provided.

Comparative Example 1 The angle of the cleaning blade provided in Example 1 was 5
When set to 0 degrees, the total length of the cleaning process is 36
It became 0 mm or more, and it was confirmed that it was practically unusable.

Comparative Example 2 The toner used in Example 1 above was used
When the pulverized toner (cyan) used in the color 4000 machine is changed and the processing after the measurement of the adhesive force is performed in the same manner as in Example 1, the results shown in Table 1 are obtained.

Comparative Example 3 The same toner as in Comparative Example 2 above was used, except that the toner was usually image
The pulverized toner (cyan) used in the Color 4000 machine was changed, and the processing after the measurement of the adhesive force was performed in Example 3 below.
When operated in the same manner as in, the results shown in Table 1 were obtained.

[0086]

[Table 1] In Table 1, “toner shape” as “toner shape” means that the surface has large and small protrusions depending on the manufacturing method.

[0087]

According to the present invention, when spherical toner is used, the toner particles remaining on the image carrier after the transfer step can be easily and efficiently cleaned, and the image formation can be efficiently recovered. The method and the image forming apparatus are provided, and the contribution to the electrophotographic field such as a copying machine, a printer, and a facsimile is extremely large.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a cleaning unit according to an image forming apparatus of the present invention.

FIG. 2 is an enlarged view of the cleaning unit of FIG.

FIG. 3 is a view showing a measuring cell of the powder adhesion measuring device.

FIG. 4 is a partial cross-sectional view of a centrifugal separator of the powder adhesion measuring device.

FIG. 5 is a partial cross-sectional view of a centrifugal separator of the horizontal powder adhesion measuring device.

[Explanation of symbols]

1 measuring cell 2 Sample substrate 2a Sample surface 3 Receiving board 3a Adhesive surface 4 spacers 5 Centrifuge 6 rotor 7 Holding member 7a Rod part 7b Cell holding unit 7c hole 7d Installation fixed part 8 Sample setting section 9 rotation center axis

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H134 GA01 GA06 GB02 HA01 HA03                       HA05 HA07 HA09 HA13 JA03                       JB01 KG04 KG07 KH01                 2H200 FA09 GA44 GB15 JC03 JC12                       JC16 LB02 LB08 LB15 LB17                       LB36 LB37 LB38 MB01 MB02                       MB04 MC01 NA02 NA08

Claims (12)

[Claims] 1. An image forming method comprising the steps of forming a toner image on an image carrier, transferring the toner image to a transfer medium, and then removing the toner remaining on the image carrier.
When a spherical toner is used in the manufacturing process or the post-manufacturing process, when cleaning the toner remaining on the image carrier or the transferred body, a cleaning member that comes into contact with the surface of the image carrier is used. Alternatively, the image forming method is characterized by contacting the surface of the transfer target at an angle with respect to a vertical axis in the driving direction. 2. As the image bearing member, the first image bearing member is an electrophotographic photosensitive member in the developing step, and the second image bearing member is an intermediate transfer member temporarily holding a toner image in the transferring step. The image forming method according to claim 1, wherein the intermediate transfer member is made of a belt-shaped conductive or semi-conductive elastic body. 3. An electrostatic latent image is formed on the first image carrier by charging and exposure, and the electrostatic latent image is developed with toner to form a toner image. After the primary transfer onto the second image carrier, the second transfer from the second image carrier to the transfer target, and then the removal of the toner remaining on the image carrier, the second image The carrier is a belt-shaped intermediate transfer member, and the cleaning member contacting the intermediate transfer member has an angle of at least 0.1 to 40 degrees with respect to a vertical axis of the driving direction of the intermediate transfer member. The image forming method according to claim 1, wherein the spherical toner remaining from the end of the intermediate transfer member is collected. 4. The image forming apparatus according to claim 1, wherein the cleaning member is composed of a cleaning roller, and the cleaning roller rotates in a direction different from a moving direction of the image carrier. Method. 5. The cleaning roller rotates in a direction different from the moving direction of the image carrier, and rotates at a linear velocity of 0.7 to 1.3 with respect to the linear velocity of the image carrier. The image forming method according to claim 4, wherein the image forming method is one. 6. The cleaning roller is made of an elastic body, and the elastic body has a volume resistance of 10 ⁵ to 10 ¹³ Ωc.
The image forming method according to claim 4 or 5, wherein m is m. 7. The image forming method according to claim 4, further comprising means for applying a voltage to the cleaning roller. 8. The adhesive force between the spherical toner and the transfer target, which is measured based on a powder adhesive force measuring method using a centrifugal separation method, includes an adhesive force in a vertical direction and an adhesive force in a horizontal direction. Ratio (horizontal adhesive force / vertical adhesive force)
9. The image forming method according to claim 1, wherein the toner is 0.3 or less. 9. The image forming method according to claim 1, wherein a toner particle collecting mechanism is provided in the vicinity of the end portion of the intermediate transfer body as a means for collecting the spherical toner. 10. The image forming method according to claim 9, wherein the toner particle collecting mechanism is a mechanism for sucking an air flow containing toner particles. 11. The image forming method according to claim 10, wherein the mechanism for sucking the air flow containing the toner particles is a mechanism for electrostatically sucking. 12. An image forming apparatus comprising: a step of forming a toner image on an image carrier, transferring the toner image to a transfer medium, and then removing the toner remaining on the image carrier. When a spherical toner is used in the manufacturing process or the post-manufacturing process, when cleaning the toner remaining on the image carrier or the transferred body, a cleaning member that comes into contact with the surface of the image carrier is used. Alternatively, the image forming apparatus is in contact with the transfer target surface at an angle with respect to the vertical axis of the driving direction.