JP2003186235A - Image forming method and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming method and image forming device which provide an electrophotographic image of sufficiently high image quality by controlling a shape factor and particle size distribution and using toner made small in particle diameter. <P>SOLUTION: In the image forming method, a latent image formed on a columnar electrophotographic photoreceptor that has a columnar degree of 5 to 40 μm is developed with developer using toner. In the toner, the ratio (Dv50/Dp50) of 50% volume particle diameter (Dv50) to 50% number particle diameter (Dp50) is 1.0 to 1.15, the ratio (Dv75/Dp75) of cumulative 75% volume particle diameter (Dv75) from the large volume particle diameter side to cumulative 75% number particle diameter (Dp75) from the large number particle diameter side is 1.0 to 1.20, and the number of toners having a particle diameter of 0.7×(Dp50) or less is 10 number % or less. <P>COPYRIGHT: (C)2003,JPO

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 used for electrophotographic copying machines, printers and the like.

[0002]

2. Description of the Related Art In recent years, with respect to an electrophotographic image forming method, digital image forming has become the mainstream due to the recent development of digital technology. The digital image forming method is basically based on visualizing a small dot image of one pixel such as 400 dpi (1 inch = the number of dots per 2.54 cm), and a high resolution that faithfully reproduces these small dot images. Image quality technology is required. In particular, in recent years, there has been an increasing demand for downsizing, high resolution, full-color copying machines and for printers. Technology is required.

In response to such demands for higher image quality, research is being conducted to control the shape factor and particle size distribution of the toner to reduce the particle size of the toner. By sharpening the shape distribution and particle size distribution of the toner and reducing the particle size of the toner, the resolution is improved, the fine gradation expression is improved, and the high image quality is realized and developed. However, the image quality improvement using the small particle size toner is not as effective as initially expected, and rather the problem due to the use of the small particle size toner may not occur. One of the problems in cleaning is the problem that the toner has a smaller particle size and the adhesion of the toner to the photoconductor is apparently increased, which makes cleaning difficult. In particular, the toner produced by the granulation polymerization method, which is an effective method for producing small particle size toner,
In addition to having a small particle size, the particles are close to spherical, so in the cleaning process of cleaning the photoconductor with the cleaning blade, the so-called "sleeping" that toner passes between the photoconductor and the edge of the cleaning blade There is a strong tendency to cause cleaning failures.

In order to solve such a problem, it is important to improve the accuracy of the process means that constitutes the electrophotographic image forming apparatus. In particular, it is required that the positional relationship between the surface of the photoconductor and the developing device, the transfer device, the cleaner, etc. be configured more strictly. If these position definitions deviate from the original positions, the image defects shown below are likely to occur.

That is, the misalignment between the photoconductor and the exposure unit causes the exposure focus of the laser beam to become weak, resulting in a reduction in resolution.

The positional deviation between the photoconductor and the developing device (Dsd) causes fog, lower image density, and lower resolution.

The positional deviation between the photoconductor and the transfer device causes deterioration of image quality such as blurring or crushing of the transferred image.

The positional deviation between the photosensitive member and the cleaning blade is accompanied by a change in the blade pressure, which causes cleaning failure and deterioration of the durability of the photosensitive member.

As described above, the displacement of the positional relationship between the photoconductor and the image forming member around the photoconductor has a great influence on the image quality of the electrophotographic image, and one of the factors that determines the positional relationship is the positional accuracy of the photoconductor. It turns out that it's not hard to imagine. Then, when the photoconductor is manufactured using a cylindrical substrate, it has been found that the cylindricity of the cylindrical substrate is an important factor that determines the accuracy of these positional relationships.

In the present invention, the relationship between the shape factor and particle size distribution of the toner and the positional accuracy of the image forming apparatus of the photoconductor using the cylindrical substrate is important in response to the above-mentioned demand for high image quality of the electrophotographic image. It was made as a result of focusing on and examining.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a sufficiently high quality electrophotographic image by using a toner having a controlled form factor and particle size distribution and a reduced particle size. An object of the present invention is to provide an image forming method and an image forming apparatus that can be used.

[0012]

DISCLOSURE OF THE INVENTION As a result of repeated studies to solve the above problems, the present inventors have found that the object of the present invention can be achieved by taking one of the following configurations. .

That is, 1. A latent image formed on a cylindrical electrophotographic photosensitive member having a cylindricity of 5 to 40 μm was measured with 50% volume particle size (Dv50) and 50%.
The ratio (Dv50 / Dp50) of the number particle diameter (Dp50) is 1.0 to 1.15, and the cumulative 75% volume particle diameter (Dv75) from the larger volume particle diameter and the larger number particle diameter Ratio of cumulative 75% number particle size (Dp75) (Dv75 /
Dp75) is 1.0 to 1.20 and the particle size is 0.
An image forming method, comprising: developing with a developer using a toner in which the number of toner particles of 7 × (Dp50) or less is 10% by number or less.

2. 50% volume particle size (Dv5
0) is 2 μm to 8 μm. The image forming method described in 1 above.

3. 3. The image forming method as described in 1 or 2 above, wherein the toner is obtained from colored particles obtained by polymerizing at least a polymerizable monomer in an aqueous medium.

4. Item 4. The image forming method described in any one of Items 1 to 3, wherein the toner is obtained from colored particles obtained by salting out / fusing at least resin particles in an aqueous medium.

5. The holding member is inserted and pressed into the inner diameter of the cylindrical substrate, and the cylindrical substrate gripped from the inside is spigot processed on the basis of the outer diameter, then both ends of the cylindrical substrate are gripped by the gripping means, and the inner diameter of the spigot processing part The photosensitive layer is formed on a cylindrical substrate whose surface has been cut according to the standard, and the cylindricity is 5 to 5.
A cylindrical electrophotographic photosensitive member having a size of 40 μm was produced, and the latent image formed on the cylindrical electrophotographic photosensitive member was measured for a ratio (Dv50) of 50% volume particle diameter (Dv50) and 50% number particle diameter (Dp50).
50 / Dp50) is 1.0 to 1.15, and the cumulative 75% volume particle size (Dv75) from the larger volume particle size and the cumulative 75% number particle size (Dp7) from the larger volume particle size.
5) the ratio (Dv75 / Dp75) is 1.0 to 1.20 and the number of toner particles having a particle size of 0.7 × (Dp50) or less is 10% by number or less. An image forming method comprising developing.

6. An image forming apparatus using the image forming method described in any one of 1 to 5 above.

The present invention will be described in detail below. The cylindricity of the present invention is based on JIS standard (B0621-1984). That is, when the cylindrical substrate is sandwiched by two coaxial geometric cylinders, the difference between the radii at the position where the distance between the two coaxial cylinders is the minimum is represented, and in the present invention, the difference between the radii is represented by μm.

The cylindrical electrophotographic photosensitive member of the present invention (hereinafter also referred to as an electrophotographic photosensitive member or a photosensitive member) has a cylindricity of 5 to 40.
μm, preferably 7 to 30 μm, and more preferably 7 to 27 μm. When it is larger than 40 μm, the above-mentioned bad results occur. If it is less than 5 μm, the yield becomes poor and the cost becomes disadvantageous. However, the cylindricity of the electrophotographic photosensitive member means the cylindricity of an area where image formation is substantially performed, and excludes a variation area of the thickness of the photosensitive layer at both ends where image formation is not performed.

The cylindricity of the present invention is measured by measuring the roundness at a total of 7 points, ie, 2 points at both ends of the cylindrical substrate, 2 points at the center, 4 points at the center and 3 points equally divided between the ends. Ask. A non-contact universal roll diameter measuring machine (manufactured by Mitutoyo Corporation) was used as a measuring instrument.

The spigot processing of the present invention means the processing of cutting the inside of a cylindrical substrate to form a processed surface such as a step (for attaching a member, etc.) on the inner surface of the substrate.
While rotating the cylindrical substrate, the cutting tool is brought into contact with it, and is fed and moved for processing.

Since the spigot processing of the present invention is mainly intended to form steps for attaching flanges to both ends of the cylindrical base body, a step having a length dmm in the axial direction of the base body at both ends of the cylindrical base body (the spigot of the present invention is used. Length). In the present invention, if the length of the cylindrical substrate (axial direction) is Lmm and the length of the holding member (axial direction) is Dmm, the length D of the holding member is D.
Is preferably in the following range.

If ½ × L ≦ D <L-2d D is smaller than ½ × L, both ends of the base body are likely to swing in the top shape during spigot processing, and the processing accuracy is likely to deteriorate. When D is L-2d or more, the space for the spigot working portion is insufficient, and the working operation becomes difficult.

The holding member of the present invention means a member which is inserted and pressure-contacted with the inner diameter of the cylindrical substrate in order to suppress vibration and prevent the deformation of the shape of the substrate during machining of the cylindrical substrate such as spigot processing.

The outer diameter reference of the present invention means that the central axis of the outer surface cylinder of the cylindrical substrate is used as the reference axis.

The inner diameter reference of the spigot working portion of the present invention means that the central axis of the inner diameter of the cylinder formed by the spigot working is used as the reference axis.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic front view of an electrophotographic photosensitive member 10 according to the present invention, which is composed of a cylindrical substrate 11 and flanges 14 and 15 provided at ends 12 and 13 which are openings on both sides thereof, and has a cylindrical shape. A photosensitive layer 16 is formed on the surface of the base 11. A shaft 17 is arranged at the center of the electrophotographic photosensitive member 10 so as to match the axis C of the cylindrical substrate 11, so that the electrophotographic photosensitive member 10 can be rotated.

The cylindrical substrate 11 is made of a conductive metal such as aluminum or an aluminum alloy and is processed into a hollow cylindrical shape. For example, when an aluminum alloy is used, it is formed into a cylindrical shape by subjecting it to stretching and / or cutting.

The flanges 14 and 15 are disc-shaped to fit the inner surfaces of both ends of the cylindrical substrate 11 to make the cylindrical substrate 11 cylindrical, and a hole 18 is formed in the center thereof. Further, one flange 14 has a gear 14 on its outer periphery.
a is formed so that the rotation of the electrophotographic photosensitive member 10 can be controlled.

The shaft 17 is a rod-shaped member made of metal, plastic or the like having a rectangular cross section, a square shape, a cross shape, a circular shape, etc., and is made of a material that is not easily deformed such as bending. Further, the shaft 17 is fixed through the holes 18 formed in the flanges 14 and 15, and serves as a shaft for supporting the rotation of the electrophotographic photosensitive member 10.

The photosensitive layer 16 is made of a photoconductive material having a photoelectric effect, such as an organic photoconductor (OPC) photosensitive layer.

In order to manufacture the electrophotographic photosensitive member of the present invention, it is first necessary to prepare the cylindrical substrate 11 to have a cylindricity of 5 to 40 μm.

FIGS. 2A to 2D show the order of steps (a) and (b) in order to explain the manufacturing steps of the cylindrical substrate according to the present invention. First, a hollow cylindrical cylindrical substrate 11 as shown in FIG. 2A is prepared. Cylindrical base 1
As 1, an aluminum alloy having a thickness of 2 mm and an outer diameter of 100 mmφ can be used, for example.

FIG. 2 (a) is a view in which the holding member 3 is inserted inside the base body and is processed by a cutting tool as a spigot process. A spigot process is applied to the end so as to provide a step inside. At this location, thin-walled portions (inlay processing portions) 12a, 13a are formed in which the outer diameter does not change but the wall thickness is reduced by the step difference to increase the inner diameter.

In the present invention, during this spigot processing, the cylindrical substrate is gripped from inside by the holding member and the pressure varying means 4, and the cylindrical substrate is driven by the motors 20 and 21 around the central axis 19 penetrating the holding member. By rotating
The turning blade 22 is brought into contact with the inside of the base body to perform the spigot working. That is, by gripping the cylindrical substrate from the inside,
It is characterized in that the surface is not damaged.

Next, the surface of the cylinder is cut by using the spigot-processed cylindrical substrate. That is, FIG. 2 (b) shows a non-sliding opening / closing chuck (manufactured by Fujii Seimitsu Kogyo Co., Ltd., which is used to open and close the gripping claws 23 on the inlay portions at both ends of the cylindrical substrate having the inner diameter formed by the inlay processing. FIG. 3 is a view showing that the surface of the substrate is cut by gripping with a balloon chuck, craftgraphy, and a diaphragm chuck manufactured by Dynamic Tool Co., Ltd.) 24, 25, and the inner surface of the spigot processing part is used as a reference.

By adopting the method for processing a cylindrical substrate as described above, a cylindrical substrate for an electrophotographic photoreceptor having an outer diameter cylindricity of 5 to 40 μm can be produced. 26 is a cutting blade.

It is preferable that the holding member is a rigid member having high strength in order to suppress vibration during spigot processing and maintain its shape. The rigid member is preferably made of metal such as stainless steel or brass, or ceramics. Further, it is preferable that the holding member is equipped with a contact pressure varying means or the like. Hereinafter, a method of inserting and pressing the rigid member into the inner diameter of the cylindrical substrate will be described.

FIG. 3A is a perspective view of the holding member 3.
FIG. 3B is a sectional view showing the pressure varying means 4 of the holding member. 3-1 to 3-8 are parts of the holding member each having a fan-shaped cross section, and each part is connected by loose connection (not shown), for example, by a spring to form the entire holding member, and the outer surface of the holding member. Has a cylindrical shape so as to contact the inner surface of the cylindrical substrate. As shown in FIG. 3B, the central portion of the holding member serves as pressure varying means 4 and has a center bar 4-1 with a taber.
It forms a ring that can be taken in and out. Figure 3 (b)
By inserting the center rod 4-1 as shown in FIG. 5, the holding member expands to the outside and holds the cylindrical substrate while pressing it. Adjust the pressure when pressing the center rod 4
It is adjusted with an insertion depth of -1.

As the holding member, an elastic member such as hard urethane or rubber can be used instead of the rigid member.

Further, the center rod 4-1 has a central shaft 19 penetrating the holding member, and the spigot working is carried out by rotationally driving the cylindrical substrate around this central shaft.

Next, after cleaning the substrate, as shown in FIG.
The photosensitive layer 16 is applied and formed on the outer surface of the cylindrical substrate 11.

Next, the flanges 14 and 15 are attached to the cylindrical substrate on which the photosensitive layer is formed. Flange 14,
Reference numeral 15 denotes a disk shape, having an outer diameter that is substantially equal to the outer diameter of the cylindrical base body 11, and is composed of an outer portion that is attached to the cylindrical base body 11 and serves as a lid, and an inner portion that has a smaller outer diameter than that. A hole 18 is formed at the center thereof. The inner portion having a small outer diameter has an outer diameter equal to or slightly larger than the inner diameters of the thin portions 12a and 13a formed by the spigot working. Inner portions of the flanges 14 and 15 having a small outer diameter are thin portions 12a and 13 of the cylindrical substrate 11, respectively.
Fit a. Thereby, the flanges 14 and 15 are fixed to the ends of the cylindrical substrate 11 so as to cover them. At this time, with the flanges 14 and 15 attached, the cylindricity around the axis C of the cylindrical substrate 11 is 5 to 40 μm.
Is preferred. A gear 14a is formed on the outer peripheral portion of the one flange 14. In addition, a hole 18 for fixing the shaft is provided at the center of the flange.

Next, the constitution of the electrophotographic photosensitive member of the present invention will be described. The photoconductor using the cylindrical substrate of the present invention can be applied to an inorganic photoconductor using selenium, amorphous silicon, etc., but is applied to an organic electrophotographic photoconductor (also referred to as an organic photoconductor) because of cost and environmental suitability. It is preferable. In the present invention, the organic photoreceptor means an electrophotographic photoreceptor constituted by giving an organic compound either one of the charge generation function and the charge transport function, which is essential for the construction of the electrophotographic photoreceptor, It includes all known organic electrophotographic photoconductors such as a photoconductor composed of a known organic charge generating substance or an organic charge transporting substance, and a photoconductor comprising a polymer complex having a charge generating function and a charge transporting function.

The layer structure of the organic photoreceptor is not particularly limited, but a charge generation layer, a charge transport layer, or a charge generation / charge transport layer (a layer having the functions of charge generation and charge transport in the same layer).
It is preferable to adopt a constitution in which a photosensitive layer such as the above and a protective layer are coated thereon.

Cylindrical Substrate The cylindrical substrate of the present invention is preferably made of a metal drum such as aluminum or nickel. The cylindrical substrate preferably has a specific resistance of 10 ³ Ωcm or less at room temperature.

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

In the present invention, an intermediate layer (lower layer) is provided between the support and the photosensitive layer in order to improve the adhesion between the conductive support and the photosensitive layer or prevent charge injection from the support. (Including a pulling layer) can also be provided. Examples of the material of the intermediate layer include a polyamide resin, a vinyl chloride resin, a vinyl acetate resin, and a copolymer resin containing two or more of repeating units of these resins. Among these undercoat resins, a polyamide resin is preferable as a resin that can reduce the increase in residual potential due to repeated use. The thickness of the intermediate layer using these resins is 0.01 to 0.5 μm.
Is preferred.

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

Photosensitive Layer The photosensitive layer structure of the photoconductor of the present invention may be a photosensitive layer structure of a single layer structure in which one layer has a charge generating function and a charge transporting function on the above-mentioned intermediate layer, but it is more preferable that the photosensitive layer is It is preferable that the function of the layer is separated into a charge generation layer (CGL) and a charge transport layer (CTL). By adopting a constitution in which the functions are separated, the increase in residual potential due to repeated use can be controlled to be small, and other electrophotographic characteristics can be easily controlled according to the purpose. In the negative charging photoreceptor, the charge generation layer (C
GL) and a charge transport layer (CTL) thereon. In the case of the photoconductor for positive charging, the order of the layers is the reverse of that of the photoconductor for negative charging. The most preferable photosensitive layer structure of the present invention is a negatively charged photosensitive member structure having the above-mentioned function separation structure.

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

As the charge generating substance (CGM), a known charge generating substance (CGM) can be used. For example, a phthalocyanine pigment, an azo pigment, a perylene pigment, an azurenium pigment or the like can be used. Among these, CGM that can minimize the increase in residual potential with repeated use
Has a steric structure and a potential structure capable of forming a stable aggregation structure among a plurality of molecules, and specific examples thereof include a phthalocyanine pigment and a perylene pigment CGM having a specific crystal structure. For example, the Bragg angle 2θ with respect to Cu-Kα rays
CGMs such as titanyl phthalocyanine having a maximum peak at 27.2 ° and benzimidazole perylene having a maximum peak at 22.4 at 27.2 have almost no deterioration due to repeated use, and the residual potential increase can be reduced.

When a binder is used as a CGM dispersion medium in the charge generation layer, a known resin can be used as the binder, but the most preferable resin is a formal resin, a butyral resin, a silicone resin, a silicone-modified butyral resin, or a phenoxy resin. Resin etc. are mentioned. The ratio of the binder resin to the charge generating substance is preferably 20 to 600 parts by mass with respect to 100 parts by mass of the binder resin. By using these resins, the increase in residual potential due to repeated use can be minimized. The thickness of the charge generation layer is preferably 0.01 μm to 2 μm.

Charge Transport Layer The charge transport layer contains a charge transport material (CTM) and a binder resin for dispersing CTM to form a film. Other substances may optionally contain additives such as antioxidants.

As the charge transport material (CTM), a known charge transport material (CTM) can be used. For example, a triphenylamine derivative, a hydrazone compound, a styryl compound, a benzidine compound, a butadiene compound or the like can be used. These charge transport materials are usually dissolved in a suitable binder resin to form a layer. Among these, CTM that can minimize the increase in residual potential due to repeated use has high mobility and has a characteristic that the difference in ionization potential with CGM to be combined is 0.5 (eV) or less, and preferably 0. It is 0.25 (eV) or less.

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

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

The most preferable binder for these CTLs is a polycarbonate resin. Polycarbonate resin is most preferable in improving dispersibility of CTM and electrophotographic characteristics. The ratio of the binder resin to the charge transport material is preferably 10 to 200 parts by mass with respect to 100 parts by mass of the binder resin. The thickness of the charge transport layer is preferably 10-40 μm.

Next, as a coating processing method for producing the electrophotographic photosensitive member of the present invention, dip coating, spray coating,
A coating processing method such as circular amount regulation type coating is used. In particular, when a circular amount regulation type coating device is used, since the lower layer film is not dissolved as much as possible, a uniform coating process can be achieved and an electrophotographic photosensitive member can be produced in which the cylindrical degree of the cylindrical substrate is maintained. Regarding the circular amount regulation type coating, for example, JP-A-58-18906.
It is described in detail in Japanese Patent No.

Next, the toner used in the present invention will be described. First, the toner used in the present invention preferably has a monodisperse particle size distribution or a particle size distribution close to that, and the 50% volume particle size (Dv50) and 50% number particle size (D).
p50) ratio (Dv50 / Dp50) is 1.0 to 1.1.
The requirement is to be 5. More preferably 1.0
~ 1.13 is preferable. If this ratio exceeds 1.15, the particle size distribution becomes wide and the object of the present invention cannot be achieved.

Further, the cumulative amount of toner particles from the larger one is 7
5% volume particle diameter (Dv75) and cumulative 75% number particle diameter (Dp
75) ratio (Dv75 / Dp75) is 1.0 to 1.20.
Must be If it exceeds 1.20, the abundance ratio of the small particle size component increases, which causes an increase in the weakly charged component, the generation of the opposite polarity toner, or the generation of the overcharged component. As a result, the resolution and the cleaning property are deteriorated, and image defects such as uneven halftone are likely to occur.

Further, it is necessary that the number of toner particles having a particle size of 0.7 × (Dp50) or less is 10% or less and 10
If it exceeds the number%, the existence ratio of the small particle size component increases, and as described above, the weakly charged component increases and the toner of the opposite polarity is generated.
Alternatively, it may cause generation of overcharged components. As a result, the resolution and the cleaning property are deteriorated, and image defects such as uneven halftone are likely to occur.

In the present invention, a latent image on a cylindrical electrophotographic photosensitive member having a cylindricity of 5 to 40 μm is developed with a developer containing a toner having the above-mentioned particle size distribution characteristic, whereby the resolution and the cleaning property are improved and It is possible to obtain an electrophotographic image with good sharpness in which uneven tone is prevented.

In general, a cylindrical electrophotographic photosensitive member having a good cylindricity is apt to cause cleaning failure, which causes deterioration of resolution and generation of halftone unevenness. By developing with a developer containing a toner having a distribution characteristic, the above-mentioned defects can be prevented and an electrophotographic image with good sharpness can be obtained.

The 50% volume particle diameter (Dv50) is preferably 2 to 8 μm, more preferably 3 to 7 μm. By setting this range, the resolution can be increased. Further, by combining with the above range of the present invention, it is possible to reduce the amount of toner having a fine particle diameter, even though it is a small particle diameter toner, and improve the cleaning property and the transfer rate of the toner for a long period of time. It is possible to form a stable image with good sharpness.

In the present invention, the accumulation from the largest 75
% Volume particle diameter (Dv75) or cumulative 75% number particle diameter (D
p75) is the volume particle size or the number particle size of the particle size distribution region in which the frequencies from the larger particle size are accumulated and each represents 75% of the sum of the total volume or the sum of the number.

In the present invention, 50% volume particle size (Dv5
0), 50% number particle size (Dp50), cumulative 75% volume particle size (Dv75), cumulative 75% number particle size (Dp75), etc. are measured by Coulter Counter TAII type or Coulter Multisizer (manufactured by Coulter). You can

Further, as the toner of the present invention, 0.7
Toner particles having a particle size of x (Dp50) or less are 10% by number, and the amount of the fine powder toner can be measured using an electrophoretic light scattering photometer ELS-800 manufactured by Otsuka Electronics Co., Ltd.

In the technical field of developing an electrostatic latent image to which the present invention belongs by dry development, an external additive is added to at least colored particles (prototype of toner particles) composed of a colorant and a resin. The thing is used as toner. However, unless there is a particular problem, the colored particles and the toner are not so distinguished from each other,
It is generally described. In terms of the particle size and the particle size distribution in the present invention, the measured value does not change regardless of whether the colored particles or the toner particles are measured.

The diameter of external additives and the like is nm order (number average primary particles), and should be measured by a light scattering electrophoresis particle size measuring device "ELS-800" (manufactured by Otsuka Electronics Co., Ltd.). Can be done.

The constitution and manufacturing method of the toner used in the present invention having the above-mentioned particle size distribution will be described in detail below.

<Toner> In the present invention, an associative toner obtained by salting out / fusing resin particles containing a releasing agent and colorant particles is preferably used as the toner.

The reason for this is that in addition to the fact that the toner having the above-mentioned particle size distribution can be produced, the associative toner has a uniform surface property between the toner particles, so that the transfer property is not impaired and the present invention can be used. It is presumed that the effect of was able to be exhibited.

The above-mentioned "salting out / fusion" means that salting out (aggregation of particles) and fusion (disappearance of interface between particles) occur simultaneously, or salting out and fusion occur simultaneously. Refers to an act. In order to carry out salting out and fusion at the same time, it is necessary to agglomerate the particles (resin particles, colorant particles) under a temperature condition equal to or higher than the glass transition temperature (Tg) of the resin constituting the resin particles.

<Release Agent> The release agent constituting the toner of the present invention is not particularly limited, but the crystalline ester compound represented by the following general formula (1) (hereinafter,
It is called a "specific ester compound". ) Is preferred.

General formula (1): R _1- (OCO-R ₂ ) _n (In the formula, R ₁ and R ₂ are each a hydrocarbon having 1 to 40 carbon atoms which may have a substituent. Group, n is 1
Is an integer of ~ 4. <Specific ester compound> In the general formula (1) representing a specific ester compound, R ₁ and R ₂ each represent a hydrocarbon group which may have a substituent.

The hydrocarbon group R ₁ has 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 2 to 5 carbon atoms.

The hydrocarbon group R ₂ has 1 to 40 carbon atoms, preferably 16 to 30, and more preferably 18 to 26.
It is said that

In the general formula (1), n is 1 to 4
And is preferably an integer of 2 to 4, more preferably 3
4 and particularly preferably 4.

The specific ester compound can be suitably synthesized by a dehydration condensation reaction between an alcohol and a carboxylic acid.

As the most preferable specific ester compound, pentaerythritol tetrabehenate can be mentioned.

Specific examples of the specific ester compound include:
The compounds represented by the following formulas 1) to 26) can be exemplified.

[0085]

[Chemical 1]

[0086]

[Chemical 2]

<Release Agent Content Ratio> The content ratio of the release agent in the toner of the present invention is usually 1 to 30% by mass, preferably 2 to 20% by mass, more preferably 3 to.
It is set to 15% by mass.

<Resin Particles Containing Release Agent> In the present invention, “resin particles containing a release agent” are obtained by dissolving the release agent in the monomer for obtaining the binder resin. It is possible to obtain latex particles by dispersing the monomer solution in an aqueous medium and subjecting this system to a polymerization treatment.

The weight average particle diameter of the resin particles is 50 to 2
It is preferably 000 nm. Examples of the polymerization method for obtaining resin particles containing a release agent in the binder resin include an emulsion polymerization method, a suspension polymerization method, and a granulation polymerization method such as a seed polymerization method.

As a preferred polymerization method for obtaining resin particles containing a releasing agent, the releasing agent is added to the monomer in an aqueous medium in which a surfactant having a concentration of not more than the critical micelle concentration is dissolved. A method of radical polymerization by adding a water-soluble polymerization initiator to the obtained dispersion to disperse the dissolved monomer solution into oil droplets using mechanical energy , "Mini-emulsion method" in this specification
Say. ) Can be mentioned. Instead of adding the water-soluble polymerization initiator, or while adding the water-soluble polymerization initiator, an oil-soluble polymerization initiator may be added to the monomer solution.

The dispersing machine for dispersing the oil droplets by mechanical energy is not particularly limited, but for example, a stirring device "CLEARMIX" (provided with a rotor rotating at high speed) ( M-Technique Co., Ltd.), an ultrasonic disperser, a mechanical homogenizer, a Manton-Gaulin, a pressure homogenizer, and the like. The dispersed particle diameter is 10 to 1000 nm, preferably 30 to 30 nm.
It is set to 0 nm.

<Binder Resin> The binder resin constituting the toner of the present invention has a molecular weight distribution measured by GPC of 10 or less.
A high molecular weight component having a peak or shoulder in the range of 10,000 to 1,000,000, and 1,000 to 20,000
It is preferable that the resin contains a low molecular weight component having a peak or a shoulder in the region.

Here, as a method for measuring the molecular weight of the resin by GPC, 1 ml of THF was added to 0.5 to 5.0 mg (specifically 1 mg) of the measurement sample, and the mixture was heated to room temperature using a magnetic stirrer or the like. And stir to dissolve well. Then, pore size 0.45-0.50 μm
After treating with the membrane filter of No. 1, it is injected into GPC.

The GPC measurement conditions were as follows: the column was stabilized at 40 ° C., and THF was flowed at a flow rate of 1 ml / min.
About 100 μl of a sample having a concentration of 1 mg / ml is injected and measured. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex GPC KF-801, 802 manufactured by Showa Denko KK
A combination of 803, 804, 805, 806, 807,
Tosoh TSKgel G1000H, G2000
H, G3000H, G4000H, G5000H, G6
000H, G7000H, TSK guard col
The combination of umn etc. can be mentioned. A refractive index detector (IR detector) or a UV detector may be used as the detector. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve prepared using monodisperse polystyrene standard particles. About 10 points may be used as polystyrene for preparing the calibration curve.

The constituent materials of the resin particles and the preparation method (polymerization method) will be described below. [Monomer] As the polymerizable monomer used to obtain the resin particles, a radical polymerizable monomer is an essential constituent component, and a crosslinking agent can be used if necessary. In addition, at least 1 of the following radical polymerizable monomer having an acidic group or radical polymerizable monomer having a basic group is used.
It is preferable to include a kind. (1) Radical polymerizable monomer: The radical polymerizable monomer is not particularly limited, and conventionally known radical polymerizable monomers can be used. Further, one kind or a combination of two or more kinds can be used so as to satisfy the required characteristics.

Specifically, aromatic vinyl monomers, (meth) acrylic acid ester monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers. A monomer, a halogenated olefin-based monomer or the like can be used.

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

Examples of the (meth) acrylic acid ester type monomer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate. , Butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, γ-aminoacrylate propyl, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and the like.

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

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

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

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

As the halogenated olefin-based monomer,
Examples thereof include vinyl chloride, vinylidene chloride, vinyl bromide and the like.

(2) Crosslinking agent: As the crosslinking agent, a radically polymerizable crosslinking agent may be added to improve the characteristics of the toner. Examples of the radical-polymerizable cross-linking agent include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate and diallyl phthalate.

(3) Radical Polymerizable Monomer Having Acidic Group or Basic Group: The radical polymerizable monomer having an acidic group or the radical polymerizable monomer having a basic group is, for example, a carboxyl group. Amine-based compounds such as a content monomer, a sulfonic acid group-containing monomer, a primary amine, a secondary amine, a tertiary amine, and a quaternary ammonium salt can be used.

Examples of the radically polymerizable monomer having an acidic group include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, maleic acid monobutyl ester, and carboxylic acid group-containing monomers. Maleic acid monooctyl ester etc. are mentioned.

Examples of the sulfonic acid group-containing monomer include styrene sulfonic acid, allyl sulfosuccinic acid, and octyl allyl sulfosuccinate.

These may have a structure of an alkali metal salt such as sodium or potassium or an alkaline earth metal salt such as calcium.

Examples of the radical polymerizable monomer having a basic group include amine compounds, such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and quaternary compounds of the above four compounds. Ammonium salt, 3-dimethylaminophenyl acrylate, 2-hydroxy-3-methacryloxypropyltrimethylammonium salt, acrylamide, N-butylacrylamide, N, N-dibutylacrylamide,
Piperidyl acrylamide, methacrylamide, N-butyl methacrylamide, N-octadecyl acrylamide; vinyl pyridine, vinyl pyrrolidone; vinyl N-methylpyridinium chloride, vinyl N-ethylpyridinium chloride, N, N-diallylmethylammonium chloride, N, N- Examples include diallylethylammonium chloride.

As the radical-polymerizable monomer used in the present invention, a radical-polymerizable monomer having an acidic group or a radical-polymerizable monomer having a basic group is used in an amount of 0.1 to 15 of all monomers. The radical-polymerizable cross-linking agent is preferably used in an amount of 0.1 to 10 mass% with respect to the total radical-polymerizable monomers, although it depends on its characteristics.

[Chain Transfer Agent] A commonly used chain transfer agent can be used for the purpose of adjusting the molecular weight of the resin particles.

The chain transfer agent is not particularly limited, and examples thereof include mercaptans such as octyl mercaptan, dodecyl mercaptan and tert-dodecyl mercaptan, mercaptopropionic acid esters such as n-octyl-3-mercaptopropionic acid ester, and tetracarboxylic acid esters. Carbon bromide and styrene dimer are used.

[Polymerization Initiator] The radical polymerization initiator used in the present invention can be appropriately used as long as it is water-soluble.
For example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4′-azobis-4-cyanovaleric acid and its salts, 2,2′-azobis (2-amidinopropane) salt, etc.), peroxides A compound etc. are mentioned.

Further, the above radical polymerization initiator can be used as a redox type initiator in combination with a reducing agent, if necessary. By using the redox type initiator, the polymerization activity can be increased, the polymerization temperature can be lowered, and further shortening of the polymerization time can be expected.

Any temperature may be selected as the polymerization temperature as long as it is at least the minimum radical generation temperature of the polymerization initiator, but for example, a range of 50 ° C. to 90 ° C. is used. However, it is also possible to polymerize at room temperature or higher by using a combination of a polymerization initiator that starts at room temperature, for example, a combination of hydrogen peroxide and a reducing agent (ascorbic acid, etc.).

[Surfactant] In order to carry out polymerization using the above-mentioned radically polymerizable monomer, it is necessary to disperse oil droplets in an aqueous medium using a surfactant. The surfactant that can be used in this case is not particularly limited, but the following ionic surfactants can be mentioned as suitable examples.

As the ionic surfactant, sulfonates (sodium dodecylbenzene sulfonate, sodium arylalkyl polyether sulfonate, 3,3-
Disulfone diphenylurea-4,4-diazo-bis-amino-8-naphthol-6-sulfonate sodium, ortho-carboxybenzene-azo-dimethylaniline,
2,2,5,5-tetramethyl-triphenylmethane-
4,4-diazo-bis-β-naphthol-6-sulfonate, etc.), sulfuric acid ester salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (sodium oleate, laurin) Acid sodium salt, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate and the like).

Further, nonionic surfactants can also be used. Specifically, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, ester of polyethylene glycol and higher fatty acid, alkylphenol polyethylene oxide, ester of higher fatty acid and polyethylene glycol, ester of higher fatty acid and polypropylene oxide, sorbitan ester. Etc. can be mentioned.

<Colorant> Examples of the colorant constituting the toner of the present invention include inorganic pigments, organic pigments and dyes.

As the inorganic pigment, conventionally known ones can be used. Specific inorganic pigments are exemplified below.

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

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

When used as a magnetic toner, the above magnetite can be added. In this case, from the viewpoint of imparting a predetermined magnetic characteristic, 20 to 6 is contained in the toner.
It is preferable to add 0% by mass.

Known organic pigments and dyes can be used. Specific organic pigments and dyes are exemplified below.

As the magenta or red pigment,
C. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 15, C.I. I. Pigment Red 16,
C. I. Pigment Red 48: 1, C.I. I. Pigment Red 53: 1, C.I. I. Pigment Red 57:
1, C.I. I. Pigment Red 122, C.I. I. Pigment Red 123, C.I. I. Pigment Red 139,
C. I. Pigment Red 144, C.I. I. Pigment Red 149, C.I. I. Pigment Red 166, C.I.
I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222 and the like.

Pigments for orange or yellow include C.I. I. Pigment Orange 31, C.I. I. Pigment Orange 43, C.I. I. Pigment Yellow 12,
C. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I.
I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, C.I. I.
Pigment Yellow 138, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 185, C.I.
I. Pigment Yellow 155, C.I. I. Pigment Yellow 156 and the like.

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

As the dye, C.I. I. Solvent Red 1, 49, 52, 58, 63, 111,
122, C.I. I. Solvent Yellow 19, 44,
77, 79, 81, 82, 93, 98, 103, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93,
Id. 95 and the like can be used, and a mixture thereof can also be used.

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

The colorant may be surface-modified before use. As the surface modifier, conventionally known ones can be used, and specifically, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent and the like can be preferably used.

<External Additive> The toner of the present invention has fluidity,
A so-called external additive may be added and used for the purpose of improving charging property and cleaning property.
These external additives are not particularly limited, and various inorganic fine particles, organic fine particles and lubricants can be used.

As the inorganic fine particles, conventionally known ones can be used. Specifically, silica, titanium, alumina fine particles and the like can be preferably used. The inorganic fine particles are preferably hydrophobic. Specifically, as the silica fine particles, for example, commercially available products R805, R976, R974, R972, R8 manufactured by Nippon Aerosil Co., Ltd.
12, R809, HVK2150, H2 manufactured by Hoechst
00, commercial products TS720 and TS53 manufactured by Cabot Corporation
0, TS610, H5, MS5 and the like.

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

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

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

Examples of lubricants include zinc stearate, aluminum, copper, magnesium, calcium salts, oleic acid zinc, manganese, iron, copper, magnesium salts, and palmitic acid zinc, copper, magnesium, calcium. And the like, salts of zinc and calcium of linoleic acid, and metal salts of higher fatty acids such as salts of zinc and calcium of ricinoleic acid.

The addition amount of these external additives is preferably 0.1 to 5 mass% with respect to the toner. The toner of the present invention is preferably an associative toner obtained by salting out / fusing resin particles containing a release agent and colorant particles in an aqueous medium. Thus, by salting out / fusing resin particles containing a releasing agent, a toner in which the releasing agent is finely dispersed can be obtained, and in addition to the effect of the particle size distribution, the charging property can be improved. It is possible to exert effects such as stabilization of.

The toner of the present invention has a shape having irregularities on its surface from the time of its production, and further, it is an association type toner obtained by fusing resin particles and colorant particles in an aqueous medium. Since it is a toner, the difference in shape and surface property between the toner particles is extremely small, and as a result, the surface property tends to be uniform. For this reason, it is possible to keep the image in good condition, unlikely to cause a difference in transfer property and charging property between the toners.

<Toner Manufacturing Step> As an example of the method of manufacturing the toner of the present invention, (1) a dissolving step of dissolving a release agent in a monomer to prepare a monomer solution, and (2) obtaining Dispersion step of dispersing the obtained monomer solution in an aqueous medium, (3) dispersion of resin particles containing a release agent (latex) by polymerizing the obtained aqueous dispersion of the monomer solution
And (4) salting out / fusing step of salting / fusing the obtained resin particles and the colorant particles in an aqueous medium to obtain associated particles (toner particles), The obtained associated particles are filtered out from an aqueous medium, and a filtering / washing step of washing and removing a surfactant and the like from the associated particles, (6) a step of drying the washed associated particles, (7)
An external additive adding step of adding an external additive to the dried associated particles may be included.

[Dissolution Step] The method of dissolving the release agent in the monomer is not particularly limited.

As the amount of the release agent dissolved in the monomer, the content of the release agent in the finally obtained toner is 1 to 3.
The amount is 0% by mass, preferably 2 to 20% by mass, and more preferably 3 to 15% by mass.

It is also possible to add an oil-soluble polymerization initiator and other oil-soluble components to this monomer solution.

[Dispersion Step] The method of dispersing the monomer solution in the aqueous medium is not particularly limited, but a method of dispersing by mechanical energy is preferable, and particularly, a method of dispersing the monomer solution at a concentration equal to or lower than the critical micelle concentration is preferable. It is preferable to disperse the monomer solution in oil droplets by utilizing mechanical energy in an aqueous medium in which a surfactant is dissolved (an essential aspect in the mini-emulsion method).

The disperser for dispersing oil droplets by mechanical energy is not particularly limited, and examples thereof include "Clearmix", ultrasonic disperser, mechanical homogenizer, manton-gorin and pressure. A formula homogenizer etc. can be mentioned. The dispersed particle size is 10 to 1000 nm, preferably 30 to 300 nm.

[Polymerization Step] In the polymerization step, a conventionally known polymerization method (emulsion polymerization method, suspension polymerization method, granulation polymerization method such as seed polymerization method) can be basically used.

As an example of a preferable polymerization method, a miniemulsion method, that is, a monomer solution is oiled by using mechanical energy in an aqueous medium in which a surfactant having a concentration of a critical micelle concentration or less is dissolved. There may be mentioned a method in which a water-soluble polymerization initiator is added to the dispersion liquid obtained by the droplet dispersion to carry out radical polymerization.

[Salting-out / fusion-bonding step] In the salting-out / fusion-bonding step, a dispersion of colorant particles is added to the dispersion of resin particles obtained by the above-mentioned polymerization step, and the resin particles and the above-mentioned coloring are added. The agent particles are salted out / fused in an aqueous medium.

In addition, in the salting-out / fusing step, internal additive particles such as a charge control agent may be fused together with the resin particles and the colorant particles.

The "water-based medium" in the salting-out / fusion-bonding step means that the main component (50% by mass or more) is water. Examples of the components other than water include organic solvents that are soluble in water, and examples thereof include methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, and tetrahydrofuran.
Of these, alcohol-based organic solvents such as methanol, ethanol, isopropanol and butanol, which are organic solvents that do not dissolve the resin, are particularly preferable.

The colorant particles used in the salting-out / fusion step can be prepared by dispersing the colorant in an aqueous medium. The dispersion treatment of the colorant is performed in water in a state where the surfactant concentration is equal to or higher than the critical micelle concentration (CMC).

The disperser used for the dispersion treatment of the colorant is not particularly limited, but is preferably "Clearmix", an ultrasonic disperser, a mechanical homogenizer, a pressure disperser such as Manton-Gaulin or a pressure homogenizer, and a sand grinder. A medium type disperser such as a Getzman mill or a diamond fine mill can be used. The surfactant used may be the same as the above-mentioned surfactant.

The colorant (particles) may be surface-modified. In the surface modification method of the colorant, the colorant is dispersed in a solvent, the surface modifier is added to the dispersion, and the temperature of this system is raised to react. After the reaction is completed, the colorant is filtered off, washed and filtered with the same solvent repeatedly, and then dried to obtain a colorant (pigment) treated with a surface modifier.
Is obtained.

In the salting-out / fusion method, a salting-out agent comprising an alkali metal salt and / or an alkaline earth metal salt or the like is coagulated in water in which resin particles and colorant particles are present at a critical coagulation concentration or more. This is a step of adding as an agent and then heating the resin particles to a temperature not lower than the glass transition point thereof to promote salting out and at the same time perform fusion. In this step, an organic solvent insoluble in water may be added.

Examples of alkali metal salts and alkaline earth metal salts which are salting-out agents include lithium, potassium and sodium as alkali metals, and magnesium, calcium, strontium, barium and the like as alkaline earth metals. And preferably potassium, sodium, magnesium, calcium, or barium. Examples of the salt include chlorine salt, bromine salt, iodine salt, carbonate salt, and sulfate salt.

Further, as the organic solvent infinitely soluble in water, methanol, ethanol, 1-propanol,
2-propanol, ethylene glycol, glycerin,
Examples thereof include acetone, but alcohols having 3 or less carbon atoms such as methanol, ethanol, 1-propanol, and 2-propanol are preferable, and 2-propanol is particularly preferable.

In the salting-out / fusion-bonding step, it is preferable to shorten the time after the salting-out agent is added (the time until heating is started) as short as possible. That is, it is preferable that after the salting-out agent is added, the heating of the dispersion liquid of the resin particles and the colorant particles is started as quickly as possible to reach the glass transition temperature of the resin particles or higher.

Although the reason for this is not clear, the agglomeration state of the particles fluctuates, the particle size distribution becomes unstable, and the surface property of the fused toner fluctuates depending on the standing time after salting out. Or problems occur.

Time to start heating (leave time)
Is usually within 30 minutes, preferably within 10 minutes.

The temperature at which the salting-out agent is added is not particularly limited, but it is preferably below the glass transition temperature of the resin particles.

In the salting out / fusion step, it is necessary to raise the temperature quickly by heating, and the rate of temperature increase is preferably 1 ° C./minute or more. The upper limit of the temperature rising rate is not particularly limited, but it is preferably 15 ° C./minute or less from the viewpoint of suppressing the generation of coarse particles due to the rapid progress of salting out / fusion.

Further, after the dispersion liquid of the resin particles and the colorant particles reaches the temperature of the glass transition temperature or higher, the temperature of the dispersion liquid is maintained for a certain period of time so that salting out / fusion can be continued. It is essential. As a result, the growth of toner particles (aggregation of resin particles and colorant particles) and fusion (disappearance of the interface between particles) can be effectively progressed, and the durability of the finally obtained toner is improved. can do.

After stopping the growth of associated particles,
The fusion by heating may be continued.

[Filtration / Washing Step] In this filtration / washing step, a filtering treatment for filtering the toner particles from the dispersion liquid of the toner particles obtained in the above step, and the filtered toner particles (cake-shaped A cleaning process is performed to remove deposits such as surfactants and salting-out agents from the aggregate.

Here, the filtration method is not particularly limited, such as a centrifugal separation method, a vacuum filtration method using a Nutsche or the like, or a filtration method using a filter press or the like.

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

As the dryer used in this step, a spray dryer, a vacuum freeze dryer, a vacuum dryer, etc. can be mentioned. A stationary shelf dryer, a mobile shelf dryer, a fluidized bed dryer, a rotary dryer It is preferable to use a dryer or a stirring dryer.

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

It should be noted that the dried toner particles are
When the aggregates are aggregated by the weak attraction between particles, the aggregates may be crushed. Here, as the disintegration processing device,
A mechanical crushing device such as a jet mill, a Henschel mixer, a coffee mill or a food processor can be used.

[Step of Adding External Additive] This step is a step of adding the external additive to the dried toner particles.

The equipment used to add the external additive includes a Turbuler mixer, a Hensiel mixer,
Various known mixing devices such as a Nauta mixer and a V-type mixer can be mentioned.

Further, the toner of the present invention is 0.7 × (D
The toner having a particle size of p50) or less is 10% by number or less.
In order to adjust the particle size distribution within this range, it is preferable to narrow the temperature control in the salting out / fusion step. Specifically, it is to raise the temperature as quickly as possible, that is, to raise the temperature quickly. The conditions are those shown in the above-mentioned conditions, the time until the temperature rise is less than 30 minutes, preferably less than 10 minutes, and the rate of temperature rise is 1 to 15 ° C.
/ Min is preferred.

In the toner of the present invention, a material capable of imparting various functions as a toner material may be added in addition to the colorant and the release agent. Specific examples include charge control agents. These components can be added by various methods such as a method of adding the resin particles and the colorant particles at the same time as the salting-out / fusing step and incorporating them into the toner, a method of adding them to the resin particles themselves.

Similarly, various charge control agents are known,
Moreover, the thing which can be disperse | distributed in water can be used. Specifically, nigrosine dyes, metal salts of naphthenic acid or higher fatty acids, alkoxylated amines,
Examples thereof include secondary ammonium salt compounds, azo-based metal complexes, salicylic acid metal salts or metal complexes thereof.

<Developer> The toner of the present invention may be used as a one-component developer or a two-component developer.

When used as a one-component developer, 0.1 to 0.5 μm is contained in a non-magnetic one-component developer or toner.
A magnetic one-component developer containing a certain amount of magnetic particles can be used, and any one can be used.

Further, it can be used as a two-component developer by mixing with a carrier. In this case, conventionally known materials such as metals such as iron, ferrite and magnetite and alloys of these metals with metals such as aluminum and lead can be used as the magnetic particles of the carrier. Ferrite particles are particularly preferable. The volume average particle diameter of the magnetic particles is 15 to 100 μm, and more preferably 25 to 80 μm.
μm is preferable.

The volume average particle diameter of the carrier is typically measured by a laser diffraction type particle size distribution measuring apparatus “HELOS” (sympathic (SYMP)
(Made by ATEC)).

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

<Image Forming Method and Image Forming Apparatus> FIG.
FIG. 3 is a sectional view of an example of an image forming apparatus for carrying out the image forming method of the present invention.

In FIG. 5, reference numeral 50 denotes a photosensitive drum (photosensitive member) which is an image bearing member, and an organic photosensitive layer is coated on the drum.
A photosensitive member having the resin layer of the present invention applied thereon is grounded and driven and rotated clockwise. Reference numeral 52 denotes a scorotron charger (charging means) for uniformly charging the peripheral surface of the photosensitive drum 50 by corona discharge. This charger 5
Prior to the charging by 2, the exposure may be performed by the pre-charge pre-exposure unit 51 using a light emitting diode or the like to eliminate the history of the photo conductor in the pre-image formation to eliminate the charge on the peripheral surface of the photo conductor.

After the photosensitive member is uniformly charged, an image exposing device 53 as an image exposing means performs image exposure based on an image signal. The image exposure device 53 in this figure uses a laser diode (not shown) as an exposure light source. Rotating polygon mirror 5
Scanning on the photosensitive drum is performed by the light whose optical path is bent by the reflection mirror 532 through the 31, f.theta.
An electrostatic latent image is formed.

Here, the reversal development process of the present invention is to uniformly charge the surface of the photoreceptor by the charger 52 and develop the image-exposed area, that is, the exposed portion potential (exposed portion area) of the photoreceptor. It is an image forming method that visualizes by a step (means). On the other hand, the unexposed portion potential is not developed by the developing bias potential applied to the developing sleeve 541.

The electrostatic latent image is then developed by the developing device 54 as a developing means. A developing device 54 containing a developer composed of toner and carrier is provided on the periphery of the photosensitive drum 50, and development is performed by a developing sleeve 541 that contains a magnet and holds the developer and rotates.
Inside the developing unit 54, the developer stirring and conveying members 544, 543,
The developer is constituted by a conveyance amount regulating member 542 and the like, and the developer is agitated and conveyed to be supplied to the developing sleeve, and the supply amount is controlled by the conveyance amount regulating member. The amount of the developer conveyed varies depending on the linear velocity of the applied organic electrophotographic photosensitive member and the specific gravity of the developer, but is generally 20 to 200 m.
It is in the range of g / cm ² .

The developer is, for example, a carrier in which an insulating resin is coated around the above-mentioned ferrite core, a coloring agent such as carbon black and a charge control agent mainly composed of the above-mentioned styrene acrylic resin, and a charge control agent of the present invention. Colored particles consisting of low molecular weight polyolefin, and toner externally added with silica, titanium oxide, etc., the developer is transported to the developing zone with the layer thickness regulated by the transport amount regulating member, and development is carried out. . At this time, normally, a DC bias is applied between the photosensitive drum 50 and the developing sleeve 541, and if necessary, an AC bias voltage is applied to develop. Further, the developer is developed in a state of being in contact with or non-contacting with the photoreceptor. The potential sensor 547 measures the potential of the photoconductor.
Is provided above the developing position as shown in FIG.

After the image formation, the recording paper P is fed to the transfer area by the rotation operation of the paper feed roller 57 when the transfer timing is adjusted.

In the transfer area, the transfer electrodes (transfer means: transfer device) 58 on the peripheral surface of the photosensitive drum 50 are activated in synchronization with the transfer timing, and the recording paper P fed is sandwiched and transferred. It

Then, the recording paper P is de-charged by a separating electrode (separator) 59 which is activated almost at the same time as the transfer electrode, is separated by the peripheral surface of the photosensitive drum 50 and is conveyed to the fixing device 60, and is heated by a heat roller. 601 and pressure roller 6
The toner is melted by heating and pressurizing 02, and then discharged to the outside of the apparatus through the paper discharge roller 61. The transfer electrode 58 and the separation electrode 59 are withdrawn from the peripheral surface of the photoconductor drum 50 after the recording paper P has passed and are prepared for the next toner image formation. In FIG. 5, a corotron transfer band electrode is used as the transfer electrode 58. The transfer electrode setting conditions are:
Although it cannot be unconditionally specified because it varies depending on the process speed (peripheral speed) of the photoconductor, for example, the transfer current is +100 to +400 μA, and the transfer voltage is +500.
~ + 2000V can be set value.

On the other hand, the photosensitive drum 50 after separating the recording paper P removes and cleans the residual toner by pressing the blade 621 of the cleaning device (cleaning means) 62.
The pre-charging pre-exposure unit 51 again removes electricity and the charger 52 charges, and the next image forming process starts.

Reference numeral 70 denotes a detachable process cartridge in which a photoconductor, a charging device, a transfer device, a separator and a cleaning device are integrated.

The organic electrophotographic photoreceptor of the present invention is generally applied to electrophotographic apparatuses such as electrophotographic copying machines, laser printers, LED printers and liquid crystal shutter type printers. It can be widely applied to devices such as printing, plate making, and facsimile.

[0191]

EXAMPLES Examples of the present invention will be described below, but the invention is not limited to the following examples.

Preparation of Cylindrical Substrate 1. Substrate processing method a. Cylindrical substrate A-1. A cylindrical substrate (length L = 344 mm, diameter φ (outer diameter = 100 mm)) made of aluminum alloy and having a thickness of 2.00 mm formed by drawing and processing is applied to the contact pressure varying means of FIG. Three
-8 is used, length D = 300 mm (0.84 x L))
The stainless steel holding member is pressed and held by the inner diameter of the cylindrical substrate, and the diameter φ = 98.40 mm and the length d = 8 m based on the outer diameter.
m spigot processing was performed (the spigot processing was made by Egro Co., Ltd., using a precision CNC double-end processing machine BS).

After that, both ends of the cylindrical base body were gripped by using the non-sliding type open / close chuck, and the base body surface was cut based on the inner diameter of the spigot processing section (the cutting machine is SPA manufactured by Shoun Kosakusho). -5 is used). Cylindrical substrate A- after processing
No. 1 had a surface ten-point roughness Rz of 0.7 μm and a cylindricity of 8 μm.

Definition and Measuring Method of Surface Ten-Point Roughness Rz Rz of the present invention means a value of reference length 0.25 mm described in JIS B0601-1982. That is, the reference length is 0.2
It is the difference between the average height of the top 5 peaks and the average height of the 5 bottom valleys over a distance of 5 mm.

In the above, the roughness Rz was measured with a surface roughness meter (Surforder SE-30H manufactured by Kosaka Laboratory Ltd.). However, another measuring device may be used as long as the measuring device produces the same result within the error range.

B. Processing of cylindrical substrate A-2 In processing of cylindrical substrate A-1, D = 214 mm
Inlay processing and cutting processing were performed in the same manner except for (0.60 × L). The processed cylindrical substrate A-2 had a surface ten-point roughness Rz of 0.7 μm and a cylindricity of 25 μm.

C. Processing of cylindrical substrate A-3 In processing of cylindrical substrate A-1, D = 143 mm
Inlay processing and cutting processing were performed in the same manner except for (0.40 × L). The processed cylindrical substrate A-3 had a surface ten-point roughness Rz of 0.7 μm and a cylindricity of 35 μm.

D. Processing of cylindrical substrate A-4 In processing of cylindrical substrate A-1, D = 332 mm
Inlay processing and cutting processing were performed in the same manner except for (0.93 × L). The processed cylindrical substrate A-4 had a surface ten-point roughness Rz of 0.7 μm and a cylindricity of 28 μm.

E. Processing of Cylindrical Base Body B-1 (External Grasping (Outside of the Present Invention)) A holding member is not inserted into the inside of the cylindrical base body, but a gripping means is provided from the outside, that is, FIG.
After setting on the fixed V cradle 30 shown in, the presser V cradle 3
1. Cylindrical substrate A, except that after fixing the outer diameter of the cylindrical substrate 11 in 1, the spigot processing (for example, using a precision CNC double-end processing machine UB-600 manufactured by Egro Co., Ltd.) was performed by the left and right rotary drive turning tools 32. The spigot process and the cutting process were performed in the same manner as the process of -1. The processed cylindrical substrate B-1 had a surface ten-point roughness Rz of 0.7 μm and a cylindricity of 45 μm.

2. Fabrication of photoconductor In the following description, “part” means part by mass.

Preparation of Photoreceptor 1 After cleaning the cylindrical substrate A-3, the following dispersion was prepared and applied to form a conductive layer having a dry film thickness of 15 μm. <Conductive layer (PCL) composition liquid> Phenolic resin 160 parts Conductive titanium oxide 200 parts Methyl cellosolve 100 parts The following intermediate layer coating liquid was prepared. This coating solution was applied onto the conductive layer by a dip coating method to form an intermediate layer having a film thickness of 1.0 μm.

<Mid layer (UCL) composition liquid> Polyamide resin (Amilan CM-8000: manufactured by Toray) 60 parts Methanol 1600 parts 1-Butanol 400 parts The following coating composition liquids are mixed and dispersed for 10 hours using a sand mill. A charge generation layer coating solution was prepared. This coating solution was applied onto the intermediate layer by a dip coating method to form a charge generation layer having a thickness of 0.2 μm.

<Charge Generating Layer (CGL) Composition Liquid> Y-type titanyl phthalocyanine 60 parts Silicone resin solution (KR5240, 15% xylene-butanol solution: manufactured by Shin-Etsu Chemical Co., Ltd.) 700 parts 2-butanone 2000 parts Mixing the following coating composition liquids Then, it was dissolved to prepare a charge transport layer coating solution. This coating solution is applied onto the charge generation layer as disclosed in JP-A-5-58.
Coating was carried out by the circular amount regulation type coating device described in JP-A-8-189061 to form a charge transport layer having a film thickness of 20 μm, and a photoconductor 1 was produced. The cylindricity of this photoreceptor was 35 μm.

<Charge Transport Layer (CTL) Composition Liquid> Charge Transport Material (N- (4-methylphenyl) -N- {4- (β-phenylstyryl) phenyl} -p-toluidine) 200 parts Bisphenol Z-type polycarbonate (Iupilon Z300: manufactured by Mitsubishi Gas Chemical Co., Inc.) 300 parts 1,2-dichloroethane 2000 parts Preparation of Photosensitive Member 2 After cleaning the cylindrical substrate A-4, the following intermediate layer composition liquid is applied by dipping and dried at 150 ° C. for 30 minutes. An intermediate layer having a thickness of 1.0 μm was formed. <Intermediate layer (UCL) composition liquid> Zirconium chelate compound ZC-540 (Matsumoto Pharmaceutical Co., Ltd.) 200 parts Silane coupling agent KBM-903 (Shin-Etsu Chemical Co., Ltd.) 100 parts Methanol 700 parts Ethanol 300 parts The following coating composition liquid Were mixed and dispersed for 10 hours using a sand mill to prepare a charge generation layer coating solution. This coating solution was applied onto the intermediate layer by a dip coating method to form a charge generation layer having a thickness of 0.2 μm.

<Charge Generating Layer (CGL) Composition Liquid> Y-type titanyl phthalocyanine 60 parts Silicone resin solution (KR5240, 15% xylene-butanol solution: Shin-Etsu Chemical Co., Ltd.) 700 parts 2-butanone 2000 parts Mixing the following coating composition liquids Then, it was dissolved to prepare a charge transport layer coating solution. This coating liquid was applied onto the charge generation layer by the circular amount regulation type coating device to form a charge transport layer having a film thickness of 20 μm, and a photoconductor 2 was produced. The cylindricity of this photosensitive member was 29 μm. <Charge transport layer (CTL) composition liquid> Charge transport material (N- (4-methylphenyl) -N- {4- (β-phenylstyryl) phenyl} -p-toluidine) 200 parts Bisphenol Z-type polycarbonate (Iupilon Z300 : Mitsubishi Gas Chemical Co., Ltd.) 300 parts 1,2-dichloroethane 2000 parts Preparation of Photoreceptor 3 The following coating composition liquids were mixed and dissolved to prepare a protective layer coating composition, which was applied onto the CTL of the photoreceptor 2. .

<Protective Layer (OCL) Composition Liquid> Molecular Sieve 4A was added to 10 parts by mass of a polysiloxane resin consisting of 80 mol% of methyl siloxane unit and 20 mol% of methyl-phenyl siloxane unit, and allowed to stand for 15 hours for dehydration treatment. did. This resin was dissolved in 10 parts by mass of toluene, and 5 parts by mass of methyltrimethoxysilane and 0.2 parts by mass of dibutyltin acetate were added thereto to form a uniform solution. To this, 6 parts by mass of dihydroxymethyltriphenylamine was added and mixed, and this solution was applied as a protective layer having a dry film thickness of 2 μm by the circular amount regulation type coating device, and heat-cured at 120 ° C. for 1 hour, A photoconductor 3 was produced. The cylindricity of this photoreceptor was 30 μm.

Preparation of Photoreceptor 4 After washing the cylindrical substrate A-1, the following intermediate layer composition liquid was applied by a dip coating method to form an intermediate layer having a dry film thickness of 2 μm.

<Intermediate layer (UCL) composition liquid> The following intermediate layer dispersion liquid was diluted twice with the same mixed solvent, and allowed to stand overnight and then filtered (filter; Rigimesh filter manufactured by Nippon Pall Co., Ltd. nominal filtration accuracy: 5 microns). , Pressure; 5 × 10 ⁴ Pa)
Then, an intermediate layer composition liquid was prepared.

Intermediate layer dispersion liquid Polyamide resin CM8000 (manufactured by Toray) 1 part Titanium oxide SMT500SAS (manufactured by Teika; surface treatment is silica treatment, alumina treatment, and methylhydrogenpolysiloxane treatment) 3.0 parts Methanol 10 parts Dispersion was carried out in a batch manner with a sand mill as a disperser for a dispersion time of 10 hours to prepare an intermediate layer dispersion liquid.

The following composition liquids were mixed and dispersed using a sand mill to prepare a charge generation layer composition liquid. This composition liquid was applied by a dip coating method to form a dry film thickness of 0.3 μm on the intermediate layer.
m charge generating layer was formed.

<Charge Generating Layer (CGL) Composition Liquid> Y-type oxytitanyl phthalocyanine (Cu-Kα characteristic X-rays has a maximum peak angle of 2θ of 27.3 at 27.3) 20 parts Polyvinyl butyral (# 6000-C, (Manufactured by Denki Kagaku Kogyo Co., Ltd.) 10 parts t-butyl acetate 700 parts 4-methoxy-4-methyl-2-pentanone 300 parts The following composition liquids were mixed and dissolved to prepare a charge transport layer composition liquid. This composition liquid was applied on the charge generation layer by the circular amount regulation type coating device to form a charge transport layer having a film thickness of 24 μm, and a photoconductor 4 was produced. The cylindricity of this photoconductor is 15
was μm. <Charge transport layer (CTL) composition liquid> Charge transport material (N- (4-methylphenyl) -N- {4- (β-phenylstyryl) phenyl} -p-toluidine) 75 parts Polycarbonate resin "Iupilon-Z300" (Manufactured by Mitsubishi Gas Chemical Co., Inc.) 100 parts Methylene chloride 750 parts Preparation of Photosensitive Member 5 A photosensitive member 5 was prepared in the same manner as the photosensitive member 4 except that the cylindrical substrate A-1 was replaced with A-2. The cylindricity of this photoconductor is 2
It was 6 μm.

Preparation of Photoreceptor 6 (Comparative Example 1) A photoreceptor 6 was prepared in the same manner as the photoreceptor 4 except that the cylindrical substrate A-1 was replaced with B-1. The cylindricity of this photoconductor is 4
It was 3 μm.

Preparation of Toner and Developer (Latex Preparation Example 1) An anionic activator (sodium dodecylbenzene sulfonate: SDS) was placed in advance in a 5000 ml separable flask equipped with a stirrer, temperature sensor, cooling tube, and nitrogen introducing device. A solution prepared by dissolving 7.08 g in deionized water (2760 g) is added. While stirring at a stirring speed of 230 rpm under a nitrogen stream, the internal temperature is 80
The temperature was raised to ° C. On the other hand, 72.0 g of Exemplified Compound 19) was added to 115.1 g of styrene and 42.
In addition to the monomer consisting of 0 g and methacrylic acid 10.9 g,
It heated at 80 degreeC and melt | dissolved, and the monomer solution was produced.

Here, the above heating solution was mixed and dispersed by a mechanical disperser having a circulation path to prepare emulsified particles having a uniform dispersed particle diameter. Then, 0.84 g of a polymerization initiator (potassium persulfate: KPS) was added to ion-exchanged water 200
Latex particles were prepared by adding the solution dissolved in g and heating and stirring at 80 ° C. for 3 hours.

Subsequently, a polymerization initiator (KPS) 7.
A solution prepared by dissolving 73 g in 240 ml of ion-exchanged water was added, and after 15 minutes, 383.6 g of styrene at 80 ° C. and n-
Butyl acrylate 140.0 g, methacrylic acid 36.
A mixed solution of 4 g and 14.0 g of n-octyl-3-mercaptopropionic acid ester was added dropwise over 120 minutes. After completion of dropping, the mixture was heated and stirred for 60 minutes and then cooled to 40 ° C. to obtain latex particles. These latex particles are latex 1
And

(Toner Preparation Example) Production of Colored Particles 1Bk 9.2 g of sodium n-dodecyl sulfate was added to ion-exchanged water 1
Dissolve in 60 ml with stirring. To this solution, 20 g of Legal 330R (carbon black manufactured by Cabot Corporation) was gradually added with stirring, and then dispersed using CLEARMIX. Electrophoresis light scattering photometer ELS-80 manufactured by Otsuka Electronics Co., Ltd.
As a result of measuring the particle size of the above dispersion liquid using No. 0, the weight average particle size was 112 nm. This dispersion is referred to as "colorant dispersion 1".

1250 g of the above-mentioned “latex 1”, 2000 ml of ion-exchanged water and “colorant dispersion 1” were attached to a temperature sensor, a cooling pipe, a nitrogen introducing device, and a stirring device.
Place in a 4-liter four-necked flask and stir. After adjusting the temperature to 30 ° C., a 5 mol / liter sodium hydroxide aqueous solution was added to this solution to adjust the pH to 10.0.

Then, magnesium chloride hexahydrate 52.
An aqueous solution prepared by dissolving 6 g in 72 ml of ion-exchanged water was added with stirring at 30 ° C. for 5 minutes. Then, after standing for 2 minutes, the temperature rise is started and the liquid temperature is raised to 90 ° C. in 5 minutes (temperature rising rate: 12 ° C./min). In that state, the particle size was measured with a Coulter Counter TA-II, and when the volume average particle size reached 4.3 μm, an aqueous solution prepared by dissolving 115 g of sodium chloride in 700 ml of ion-exchanged water was added to stop particle growth, Further, the mixture is continuously heated and stirred at a liquid temperature of 85 ° C. ± 2 ° C. for 8 hours for salting out / fusing.

Then, the mixture was cooled to 30 ° C. under the condition of 6 ° C./min, hydrochloric acid was added to adjust the pH to 2.0, and stirring was stopped. The generated colored particles are filtered / washed under the following conditions,
Then, it dried with 40 degreeC warm air, and obtained the colored particle. This is designated as "colored particle 1Bk".

Production of Colored Particles 2Bk to 11Bk In the production of colored particles 1Bk, the production conditions relating to salting out / fusion are changed as shown in Table 1 to obtain colored particles 2Bk to 11Bk.
Bk was produced.

[0221]

[Table 1]

Next, 1% by mass of hydrophobic silica (number average primary particle diameter: 12 nm, hydrophobicity: 68) and hydrophobic titanium oxide (number average primary particles) were added to each of the above "colored particles 1Bk" to "colored particles 11Bk". Diameter: 20 nm, degree of hydrophobicity:
63) 1% by mass was added and mixed by a Henschel mixer to obtain a toner. These are referred to as "toner 1Bk" to "toner 11Bk". The average particle size and particle size distribution of these toners are measured and shown in Table 2. Each of these toners was mixed with a silicon carrier and used as a two-component developer, and a developer number corresponding to each toner was given. That is, toner 1Bk
As the developer number corresponding to, the number of the developer 1Bk is given, and the same applies hereinafter.

Regarding the physical properties such as the average particle size and the particle size distribution, no matter whether the colored particles which are the prototype of the toner or the toner (usually an external additive is added to the colored particles) is measured, There is no substantial difference in the values.

[0224]

[Table 2]

Evaluation The photoconductors 1 to 6 and the developers 1Bk to 11Bk were combined as shown in Table 3, and as an evaluation machine, a digital copying machine Konica "Situos 7075" (corona charging, laser exposure, reversal development, electrostatic transfer) manufactured by Konica Corporation was used. , Nail separation, blade cleaning, cleaning auxiliary brush roller adoption process, printing speed was 75 sheets / min). The pixel rate is 7 for cleaning and image evaluation.
% Of a character image, a portrait image, a solid white image, and a solid black image are each divided into quarters, and an original image is copied onto A4 neutral paper. The copying conditions were such that the most severe conditions were high temperature and high humidity (30 ° C., 80% RH), and continuous copying was performed on 200,000 sheets to evaluate halftone, solid white image, and solid black image. However, before the start of copying, the surface of the photoconductor was sprinkled with setting powder, the photoconductor and the cleaning blade were made to fit, and 200,000 copies were made. The evaluation items and evaluation criteria are shown below.

[0226]

[Table 3]

Evaluation Items and Evaluation Standard Image Density (Measured using RD-918 manufactured by Macbeth Co.).
The relative reflection density was measured with the reflection density of the paper being "0".
(Evaluated both at the initial stage and after 200,000 copies) ◎: 1.2 or higher at both the initial stage and after 200,000 copies: Good ○: 1.0 or higher at both the initial stage and after 200,000 copies: No problem in practical use × : At least one of the initial stage and at least one after 200,000 copies is less than 1.0: Level fog which is a problem in practical use: Judgment based on solid white image density Copy sheet not printed using Macbeth reflection densitometer "RD-918" ( The density of a blank sheet) is measured at 20 locations with absolute image densities, and the average value is taken as the blank sheet density. Next, the white background portion of the evaluation sheet on which the image was formed
Absolute image density was measured at 0 places, and the value obtained by subtracting the blank paper density from the average density was evaluated as the fog density.

⊚: 0.005 or less (good) both at the initial stage and after 200,000 copies ◯: 0.01 or less at both the initial stage and after 200,000 copies (no practical problem) ×: Initial stage and 200,000 copies At least one of the latter is 0.01
Larger (obviously, there is a problem in practical use) Resolution (determined by the ease of distinguishing character images) ◎: There is no difference in the resolution between the initial and 200,000 copies ○: Halftone images have a slight resolution after 200,000 copies There is a significant decrease in the resolution after 200,000 copies. Halftone unevenness: After the copying of 200,000 sheets, the density difference (ΔHD of a halftone image (a uniform image near a density of 0.2)).
= Maximum density-minimum density) Using a Macbeth reflection densitometer "RD-918", the density of unprinted copy paper (blank paper) was measured at 20 locations in absolute image density, and the average value was the blank paper density. And Next, the above halftone image area was measured at 20 locations at the same absolute image density, and the maximum density-minimum density was evaluated as ΔHD.

⊚: 0.05 or less (good) ◯: Greater than 0.05 and less than 0.1 (no practical problems) ×: 0.1 or more (problematic problems) Toner transfer rate Transfer by the following formula The rate (%) was calculated. However, when obtaining the transfer rate, the toner collected from the cleaning unit was not returned to the developing device but was taken in a bag.

Transfer rate (%) = {1- (mass of recovered toner / mass of consumed toner)} × 100 Cleaning property (A3 after completion of 100,000 and 200,000 copies)
10 sheets are continuously copied on paper, and it is judged by the presence or absence of defective cleaning in solid white areas. ◎: No toner slipping up to 200,000 sheets ○: No toner slipping up to 100,000 sheets ×: 100,000 sheets Occurrence of slipping of toner below and other evaluation conditions The other evaluation conditions using the above 7075 were set to the following conditions.

Charging conditions Charging device: Scorotron charger, initial charging potential of -750
V exposure condition Set the exposure amount to make the exposed portion potential -50V.

Development conditions DC bias: -550V The developer is a carrier having ferrite as a core and coated with an insulating resin, a styrene acrylic resin as a main material, a colorant such as carbon black, a charge control agent, a low molecular weight of the present invention. A toner developer obtained by externally adding silica, titanium oxide or the like to colored particles made of polyolefin was used.

Transfer conditions Transfer pole: Corona charging system Cleaning conditions Hardness 70 °, impact resilience 65%, thickness 2 in cleaning part
(Mm) and a cleaning blade having a free length of 9 mm were brought into contact with each other by a weight load method in the counter direction so as to have a linear pressure of 18 (N / m).

The evaluation results are shown in Table 4.

[0235]

[Table 4]

As is apparent from Table 4, the combination of the latent images on the cylindrical electrophotographic photosensitive member of the present invention having a cylindricity of 5 to 40 μm developed with a developer using a toner having all of the following characteristics No. 1-3, 5, 6, 8, 9 and N
o. 11 to 15 are combinations N that do not satisfy this condition.
o. The characteristics such as image density, resolution, cleaning property, halftone unevenness, and toner transfer rate are superior to those of Nos. 4, 7, and 10. Further, even if the toner satisfies all of the following characteristics (1) to (5), the combination No. using the photoconductor 6 having a cylindricity of 43 μm is used. Also in No. 16, characteristics such as resolution, cleaning property, halftone unevenness, and toner transfer rate are deteriorated. The ratio (Dv50 / Dp50) of the 50% volume particle diameter (Dv50) and the 50% number particle diameter (Dp50) of the toner is 1.0 to
It is 1.15. The ratio (Dv7) of the cumulative 75% volume particle size (Dv75) from the larger volume particle size of the toner to the cumulative 75% number particle size (Dp75) from the larger number particle size of the toner.
5 / Dp75) is 1.0 to 1.20. Among all the toners, the number of toner particles having a particle size of 0.7 × (Dp50) or less is 10 number% or less.

[0237]

As is apparent from the above examples, the image forming method satisfying the conditions of the present invention is excellent in cleaning property even when an electrophotographic image is formed with a developer using a toner having a small particle size. It is possible to form a sharp electrophotographic image without image unevenness.

[Brief description of drawings]

FIG. 1 is a schematic front view of an electrophotographic photosensitive member according to the present invention.

FIGS. 2A to 2C show the order of steps (a) and (b) in order to explain the manufacturing steps of the cylindrical substrate according to the present invention.

FIG. 3A is a perspective view of a holding member. (B) is sectional drawing which shows the pressure varying means of a holding member.

FIG. 4 is a diagram in which a photosensitive layer is formed by coating on the outer surface of a cylindrical substrate.

FIG. 5 is a cross-sectional view of an example of an image forming apparatus for carrying out the image forming method of the present invention.

FIG. 6 is an example of a spigot process for gripping the substrate outside.

[Explanation of symbols]

3 holding member 4 Pressure changing means 4-1 Center bar with taber 10 Electrophotographic photoreceptor 11 Cylindrical substrate 12a, 13a Thin part (inlay processing part) 14,15 flange 16 Photosensitive layer

Claims (6)

[Claims] 1. A latent image formed on a cylindrical electrophotographic photosensitive member having a cylindricity of 5 to 40 μm has a 50% volume particle diameter (Dv5).
0) and 50% number particle size (Dp50) ratio (Dv50 / D
p50) is 1.0 to 1.15 and the ratio of the cumulative 75% volume particle size (Dv75) from the larger volume particle size to the cumulative 75% number particle size (Dp75) from the larger volume particle size. (Dv75 / Dp75) is 1.0 to 1.20 and the number of toner particles having a particle size of 0.7 × (Dp50) or less is 1
An image forming method comprising developing with a developer using a toner of 0% by number or less. 2. A 50% volume particle diameter (Dv5) of the toner.
0) is 2 μm to 8 μm.
The image forming method described in 1 .. 3. The image forming method according to claim 1, wherein the toner is obtained from colored particles obtained by polymerizing at least a polymerizable monomer in an aqueous medium. 4. The image formation according to claim 1, wherein the toner is obtained from colored particles obtained by salting out / fusing at least resin particles in an aqueous medium. Method. 5. The holding member is inserted and pressed into the inner diameter of the cylindrical base body, and the cylindrical base body gripped from the inside is spigot processed on the basis of the outer diameter, and then both ends of the cylindrical base body are gripped by gripping means, The photosensitive layer is formed on the cylindrical substrate whose surface has been cut based on the inner diameter of the spigot processing portion, and the cylindricity is 5 to 4
A cylindrical electrophotographic photosensitive member having a diameter of 0 μm was prepared, and the latent image formed on the cylindrical electrophotographic photosensitive member was treated with a 50% volume particle diameter (D
v50) and 50% number particle size (Dp50) ratio (Dv50
/ Dp50) is 1.0 to 1.15, and the cumulative 75% volume particle diameter (Dv75) from the larger volume particle diameter and the cumulative 75% number particle diameter (Dp75) from the larger volume particle diameter. The ratio (Dv75 / Dp75) is 1.0 to 1.20,
An image forming method comprising: developing with a developer using a toner having a particle size of 0.7 × (Dp50) or less and a toner number of 10% or less. 6. An image forming apparatus, wherein the image forming method according to claim 1 is used.