JP2003029591A - Cleaning device, image forming method using it, and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning device having excellent cleaning performance that faulty cleaning is not caused even in the case of using small particle size toner aiming high image quality, and an image forming method and an image forming device each using the cleaning device. SOLUTION: This cleaning device has a cleaning roller having a conductive or semiconductive elastic body coming into contact with the surface of a photoreceptor and a cleaning blade arranged on a more downstream side in the moving direction of the photoreceptor than the cleaning roller, and the cleaning blade is held by a supporting member in a state where its surface on an opposite side to the surface abutting on the photoreceptor is brought into contact with a metallic thin plate member. The device is designed so that the free length (a) of the cleaning blade and the free length (b) of the metallic thin plate member satisfy a following expression 1. The expression 1 is 0.1<b/a<=0.9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device used for electrophotographic image formation, an image forming method using the cleaning device, and an image forming apparatus, and more particularly, to improvement of a photoconductor cleaning technique. .

[0002]

2. Description of the Related Art In recent years, in electrophotographic image forming apparatuses, the particle size of toner has been reduced from the viewpoint of high image quality. By using a toner with a small particle size, high resolution can be achieved by improving resolution and fine gradation expression. The problem of occurs. 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, a toner produced by the granulation polymerization method, which is an effective method for producing a toner having a small particle size, has a small particle size and particles having a substantially spherical shape. ,
In a cleaning process of cleaning the photoconductor with a blade (also simply referred to as a blade), there is a strong tendency that the toner passes through between the photoconductor and the edge of the cleaning blade, so-called "slipping", and cleaning failure occurs.

As a countermeasure against such a cleaning failure, Japanese Patent Laid-Open No. 3-189675 proposes a cleaning method in which an electrostatic toner removing action is added to a mechanical toner removing action by a cleaning blade. In the cleaning method disclosed in the above-mentioned publication, a brush roller to which a bias voltage is applied is provided on the upstream side of the cleaning blade.

[0004]

However, it has been found that the cleaning method described in the above publication has the following problems.

(1) Since most of the toner is removed from the photoconductor by the brush roller arranged on the upstream side,
The amount of toner adhering to the surface of the photoconductor with which the cleaning blade comes into contact is small. In the cleaning action of the cleaning blade, the toner acts as a lubricant between the surface of the photoconductor and the cleaning blade, but since the toner as the lubricant is removed by the brush roller, the frictional force increases and "Blade flipping" in which the cleaning blade does not slide smoothly against the body and the cleaning edge reverses
That phenomenon occurs.

As a cleaning method which is an improvement of the method disclosed in Japanese Patent Laid-Open No. 3-189675, Japanese Patent Application No. 11-272.
No. 003 proposes a cleaning method in which a cleaning roller to which a voltage is applied is arranged on the upstream side of the cleaning blade.

This method is superior to the cleaning method using the brush roller method disclosed in Japanese Patent Laid-Open No. 3-189675,
A good cleaning effect can be obtained. However, it has been found that there is room for further improvement in order to further improve the cleaning performance and make it usable for a longer period of time. That is, it has been found that it may be difficult to maintain good cleaning performance for a long period of time by the cleaning method in which the cleaning roller is arranged on the upstream side of the cleaning blade.

This phenomenon is because the frictional force between the photoconductor and the cleaning blade is not stable, and as a result, the moving speed of the photoconductor and the cleaning roller is not stable at the contact portion, and as a result, they are formed between the two. The generated electric field becomes unstable, and cleaning failure easily occurs.

Further, the toner once transferred to the cleaning roller due to electrostatic force may retransfer to the photosensitive member and cause cleaning failure.

An object of the present invention is to provide a cleaning device which solves the above problems in the conventional cleaning technique and has excellent cleaning performance. An image forming method and an image forming apparatus using the cleaning device are provided. Is to provide.

[0011]

The above-mentioned objects of the present invention are as follows.
It is achieved by any of the following inventions.

1. The electrostatic latent image formed on the photoconductor is developed with a developer containing toner, the toner image visualized by the development is transferred to a transfer material, and then the toner remaining on the photoconductor is removed. In the cleaning device, the cleaning device includes a cleaning roller having a conductive or semi-conductive elastic body that contacts the surface of the photoconductor, and a cleaning blade disposed downstream of the cleaning roller in the moving direction of the photoconductor. And, the cleaning blade is held by the support member in close contact with the metal thin plate member on the surface opposite to the surface contacting the photosensitive member,
A cleaning device characterized in that the free length a of the cleaning blade and the free length b of the thin metal plate member are designed so as to satisfy Expression 1.

Formula 1 0.1 <b / a ≦ 0.9 2. The electrostatic latent image formed on the photoconductor is developed with a developer containing toner, the toner image visualized by the development is transferred to a transfer material, and then the toner remaining on the photoconductor is removed. In the cleaning device, the cleaning device includes a cleaning roller having a conductive or semi-conductive elastic body that contacts the surface of the photoconductor, and a cleaning blade disposed downstream of the cleaning roller in the moving direction of the photoconductor. And the cleaning blade is held by a supporting member in close contact with the metal thin plate member on the surface opposite to the surface abutting on the photoconductor, and the cleaning blade has a thickness t ₁ and a thickness of the metal thin plate member. A cleaning device, characterized in that t ₂ is designed to satisfy Equation 2.

Formula 2 1/200 ≦ t ₂ / t ₁ ≦ 1 3. 3. The cleaning apparatus according to 1 or 2, wherein the cleaning roller is applied with a bias voltage having a polarity opposite to a charging polarity of toner that contributed to toner image formation during the development.

4. The cleaning device according to the above 3, wherein a bias voltage is applied to the cleaning roller by a constant current power supply.

5. 5. The cleaning device according to 4, wherein the constant current power source outputs a constant current of 1 μA to 50 μA.

6. The cleaning roller is 10 ² Ω
6. The cleaning device according to any one of 1 to 5 above, which has a surface resistivity of 10 to 10 ¹⁰ Ω.

7. 7. The cleaning device according to any one of 1 to 6 above, wherein the cleaning roller is made of a foam material and a resin film covering the foam material.

8. The cleaning blade is 0.1
8. The cleaning device according to any one of 1 to 7 above, wherein the cleaning device is brought into contact with the photoconductor in a counter method to perform cleaning under a weight of N / m to 30 N / m.

9. The cleaning blade is 0 ° to
The cleaning is carried out by contacting the photoconductor with a counter method at a contact angle θ of 40 °.
8. The cleaning device according to any one of 8 above.

10. The electrostatic latent image formed on the photoconductor is developed with a developer containing toner, the toner image visualized by the development is transferred from the photoconductor to the transfer material, and then the residual toner on the photoconductor is removed. An image forming method having a cleaning device for removing, wherein the residual toner on the photoconductor is removed by using the cleaning device according to any one of 1 to 9 above.

11. 11. The toner according to 10, wherein the toner has a variation coefficient of shape coefficient of toner particles of 16% or less and a number variation coefficient of 27% or less in a number particle size distribution of the toner particles. Image forming method.

12. The toner has a shape factor of 1.
10 or 1, wherein a toner containing 65% by number or more of toner particles in the range of 2 to 1.6 is used
1. The image forming method described in 1.

13. 13. The image forming method as described in any one of 10 to 12, wherein a toner containing 50% by number or more of toner particles having no corners is used as the toner.

14. An image forming apparatus using the image forming method described in any one of 10 to 13 above.

By adopting the above-mentioned configuration of the present invention, the inventors of the present invention can prevent the toner remaining on the organic photoconductor from being excessively increased in the frictional force generated between the organic photoconductor and the cleaning blade, and the blade can be turned up and the toner can be removed. It has been found that it is possible to prevent the occurrence of slip-through and effectively remove the toner remaining on the organic photoconductor, and to obtain a good and stable image for a long period of time. Hereinafter, the present invention will be described in detail.

FIG. 1 is a schematic configuration diagram showing the overall configuration of the image forming apparatus of the present invention. The image forming apparatus shown in FIG.
The digital image forming apparatus is composed of an image reading section A, an image processing section B (not shown), an image forming section C, and a transfer sheet conveying section D as a transfer sheet conveying means.

At the upper part of the image reading section A is provided an automatic document feeding means for automatically feeding a document, and the document table 1
The original document placed on 11 is separated and conveyed by the original document conveyance roller 112 to one sheet, and an image is read at the reading position 113a. The document for which the document reading is completed is ejected onto the document ejection tray 114 by the document conveying roller 112.

On the other hand, the image of the original placed on the platen glass 113 is read in a V-shape by the reading operation at the speed v of the first mirror unit 115 including the illumination lamp and the first mirror constituting the scanning optical system. It is read by the movement of the second mirror unit 116 including the positioned second mirror and third mirror in the same direction at the speed v / 2.

The read image is formed on the light receiving surface of the image pickup device CCD, which is a line sensor, through the projection lens 117. The linear optical image formed on the image sensor CCD is photoelectrically converted into an electrical signal (luminance signal) and then A / D converted, and the image processing unit B performs density conversion, filter processing, and the like. After being processed, the image data is once stored in the memory.

In the image forming section C, as an image forming unit, a drum-shaped photoconductor (hereinafter also referred to as a photoconductor drum) 121, which is an image carrier, and a charger 122, which is a charging unit, and a developing unit are provided on the outer periphery thereof. A developing device 123, a transfer unit 124 as a transfer unit, a separator 125 as a separation unit,
A cleaning device 126 and a PCL (pre-charge lamp) 127 are arranged in the order of operation. Photoconductor 12
Reference numeral 1 is a photoconductive compound coated and formed on a drum substrate. For example, an organic photoconductor (OPC) is preferably used, and the photoconductor is driven and rotated clockwise in the drawing.

The rotating photoconductor 121 is uniformly charged by the charger 122, and then the exposure optical system 130 performs image exposure based on the image signal called from the memory of the image processing section B. Exposure optical system 1 as writing means
30 uses a laser diode (not shown) as a light source,
The optical path is bent by the reflection mirror 132 through the rotating polygon mirror 131, the fθ lens (no reference sign), and the cylindrical lens (no reference sign), and main scanning is performed. Image exposure is performed on the photoconductor 121 at the position Ao. The latent image is formed by the rotation (sub-scanning) of the photoconductor 121. In the example of this embodiment, the character portion is exposed to form a latent image.

The latent image on the photoconductor 121 is subjected to reversal development by the developing device 123, and a visible toner image is formed on the surface of the photoconductor 121. In the transfer paper transport unit D, a paper feed unit 141 (A) as transfer paper storage means in which transfer papers P of different sizes are stored below the image forming unit,
141 (B) and 141 (C) are provided, and a manual paper feeding unit 142 for manually feeding paper is provided on the side, and the transfer paper P selected from any of them is guided by a guide roller 143. Paper is fed along the transport path 140,
The transfer sheet P is temporarily stopped and then re-fed by the registration roller pair 144 that corrects the inclination and deviation of the fed transfer sheet, and then the transfer sheet P and the pre-transfer roller 143a.
Also, the photoconductor 121 is guided by the transfer approach guide plate 146.
The above toner image is transferred to the transfer paper P by the transfer device 124 at the transfer position Bo, and then is discharged by the separator 125 to separate the transfer paper P from the surface of the photoconductor 121, and is conveyed to the fixing device 150 by the conveying device 145. It

The fixing device 150 has a fixing roller 151 and a pressure roller 152, and fixes the transfer paper P to the fixing roller 15
By passing between 1 and the pressure roller 152,
The toner is fused by heating and pressing. The transfer paper P on which the toner image has been fixed is discharged onto the paper discharge tray 164.

FIG. 2 is a block diagram of the cleaning device of the present invention. The cleaning device is a cleaning blade 12.
6A and a cleaning roller 126C. The cleaning blade 126A is supported by a fixed supporting member (blade holder) 126F, and the tip edge of the cleaning blade 126A is in pressure contact with the photoconductor 121 at a substantially constant pressure due to the elasticity of the blade. Further, as shown in FIG. 2, it is preferable that the tip portion of the cleaning blade forms a pressure contact surface when pressure contacting with the photosensitive member. As the support member 126F, it is also possible to use a support member that is rotatable about an axis and that applies a constant pressure contact force to the cleaning blade 126A by weighting with a spring or gravity. The tip of the cleaning blade 126A and the photoconductor 12 are
The contact angle θ with 1 forms an acute angle, that is, the photoconductor 121 is contacted in a counter method with respect to the photoconductor rotating direction.

In the present invention, the contact load P and the contact angle θ of the cleaning blade on the photosensitive member are preferably P = 5 to 40 N / m and θ = 5 to 35 °.

The contact load P is the cleaning blade 126.
Pressure contact force P'when A is brought into contact with the photosensitive drum 121
Is the vector value of the normal direction of.

The contact angle θ represents the angle between the tangent line X at the contact point A of the photosensitive member and the blade before deformation (shown by the dotted line in the drawing). 126E is the rotation axis of the support member, and
26G indicates a load spring.

A bias voltage is applied to the cleaning roller 126C by a constant current power source 126H, and the photosensitive member 1
The toner on 21 is electrostatically cleaned by the cleaning roller 126C.
Aspirate into. The polarity of the bias voltage contributes to the development in the developing device (developing device 123) and is opposite to the polarity of the toner forming the toner image. Cleaning roller 12
As shown in FIG. 2, a scraper 126D as a removing unit comes into contact with the 6C by a counter method to remove the toner collected from the photoconductor 121 and attached to the cleaning roller 126C.

The details of the cleaning device of the present invention will be described below for each constituent element. Cleaning Blade and Metal Thin Plate Member In the cleaning device used in the present invention, the cleaning blade 126A and the metal thin plate member 126B are the supporting members 126F.
Is attached to. A rubber elastic body is used as the material of the cleaning blade, and urethane rubber, silicon rubber, fluorine rubber, chloropyrene rubber, butadiene rubber, etc. are known as the material.
Urethane rubber is particularly preferable because it has excellent wear characteristics as compared with other rubbers. For example, urethane rubbers obtained by reacting and curing the polycaprolactone ester and polyisocyanate described in JP-A-59-30574 are preferable.

The thin metal plate member of the present invention has a thickness of 0.
It is a metal plate having a thickness of 01 to 2 mm, particularly preferably 0.02 to 0.5 mm, and means a member having a shape capable of being bonded to a cleaning blade. As the material of the metal thin plate, any metal material can be used as long as it is a flexible metal thin plate, but SUS300 is preferable.
System, SUS400 series stainless steel plate, aluminum plate,
A phosphor bronze plate or the like is used.

In the present invention, the thin metal plate member 126 is used.
B and cleaning blade 126A to support member 126F
2, the cleaning blade is attached to and held by the support member in close contact with the thin metal plate member on the surface opposite to the surface contacting the photosensitive member. At this time, a portion where the cleaning blade and the thin metal plate member are in contact with each other has a mechanism capable of reliably transmitting and absorbing the vibration generated by the blade to the thin metal plate member. By adopting such a holding method, the vibration of the cleaning blade can be effectively absorbed by the thin metal plate member, and the vibration of the blade can be stabilized. As a result, at the contact portion between the photoconductor and the cleaning roller, the moving speed of the both is stable, the effect of removing the charge of the toner by the cleaning roller is stable, and the cleaning property is maintained good for a long period of time.

That is, the proper pressure contact condition of the cleaning blade to the surface of the photosensitive member is determined by a delicate balance of various characteristics and is quite narrow. It depends on the characteristics such as the thickness of the cleaning blade, and the setting requires accuracy. However, since the cleaning blade can inevitably have some variation in its thickness at the time of manufacture, it cannot be said that it is always set under appropriate conditions. It may be out of the proper range. In particular, when combined with an organic photosensitive layer using a high molecular weight binder resin, deviation from the proper area may cause blade turning and toner slipping.

Therefore, the present invention is an effective means for canceling the variation in the characteristics of the cleaning blade, and even if the variation in the thickness of the cleaning blade is compared, the vibration of the blade due to the thin metal plate member can be effectively suppressed. By absorbing, the setting condition of the cleaning blade on the photoconductor surface can be stably maintained within the proper region.

The positional relationship between the cleaning blade and the thin metal plate member of the present invention is such that a step is provided between the tips of both members as shown in FIG. Further, the free length of the thin metal plate member is shorter than the free length of the cleaning blade. With this configuration, the vibration of the cleaning blade is absorbed by the thin metal plate member without disturbing the deformation at the tip of the cleaning blade (deformation caused by pressure contact with the photoconductor), and the vibration of the cleaning blade. Can be stabilized.

In the cleaning device of the present invention, the ratio of the free lengths of the cleaning blade and the thin metal plate member satisfies the formula 1, where the free length of the cleaning blade is a and the free length of the thin metal plate member is b, as shown in FIG. Is designed to The free length is the length of the cleaning blade, the metal thin plate member, and the portion not held by the respective supporting members. As shown in FIG. 2, the cleaning blade from the end B of the supporting member 126F and the metal thin plate are not deformed. It shows the length to the tip of each member.

Expression 1 0.1 <b / a ≦ 0.9 b / a within the above range, that is, b / a exceeds 0.1, and 0.
By designing it so that it is 9 or less, deformation of the cleaning blade at the tip portion (deformation caused by pressure contact with the photosensitive member) is not hindered, and vibration of the cleaning blade is absorbed by the thin metal plate member, and the blade is turned up. It has been found that stable cleaning performance can be realized without causing toner or toner slipping. Further, according to the present invention,
The range of 3 to 0.7 is more preferable. On the other hand, b / a is 0.
If it is 1 or less, toner slippage is likely to occur and b / a
If the ratio is larger than 0.9, the blade is likely to be turned over.

The ratio of the thickness of the cleaning device the cleaning blade and the sheet metal member of the present invention t ₁ the thickness of the cleaning blade as shown in Figure 2, when the thickness of the sheet metal member and t _2, wherein It is designed to satisfy 2.

Formula 2 1/200 ≦ t ₂ / t ₁ ≦ 1 t ₂ / t ₁ is within the above range, that is, the value of t ₂ / t ₁ is 1/200.
By designing it to be ~ 1, the cleaning blade is stably held by the support member, and the vibration of the cleaning blade is absorbed by the thin metal plate member, so that stable cleaning performance without blade flipping or toner slipping is realized. I found what I could do. Furthermore, t ₂
The value of / t ₁ is preferably in the range of 1/100 to 1/4. On the other hand, when t ₂ / t ₁ is less than 1/200, toner slipping-through is likely to occur, and when t ₂ / t ₁ is greater than 1, blade curling is likely to occur.

The free length a of the cleaning blade represents the length from the position of the end B of the supporting member 126F to the tip point of the blade before deformation as shown in FIG. The preferable value of the free length is a = 6 to 15 mm. The thickness of the cleaning blade is preferably 0.5 to 10 mm. Here, the thickness of the cleaning blade and the thin metal plate member of the present invention indicates the direction perpendicular to the bonding surface of the supporting member 126F as shown in FIG.

As other physical properties of the cleaning blade, the hardness is 25 ± 5 ° C. and the JIS A hardness is 55-55.
A range of 90 is preferred. If it is smaller than 55, the cleaning performance tends to be deteriorated, and if it is larger than 90, the blade is likely to be reversed. The impact resilience of the cleaning blade is preferably in the range of 25-80. If the impact resilience exceeds 80, the blade may be easily inverted,
If it is less than this, the cleaning performance is deteriorated. Young's modulus is 2
It is preferably in the range of 94 to 588 N / cm ² .

If necessary, the cleaning blade may be sprayed with a fluorine-based lubricant at the edge of the cleaning blade that comes into contact with the photosensitive member, or may be further applied to the tip of the cleaning blade over the entire width direction. It is preferable to apply a dispersion prepared by dispersing a fluorine-based polymer and a fluorine-based resin powder in a fluorine-based solvent.

Cleaning Roller The cleaning roller 126C is preferably a conductive or semi-conductive and elastic cleaning roller.

The cleaning roller 126C has a power source 12
By 6H, a voltage having a polarity opposite to that of the toner involved in the development is applied. That is, when development is performed with negatively charged toner and the negatively charged toner forms a toner image, a positive bias voltage is applied to the cleaning roller 126C by the power source 126H.

A rubber elastic body is used as the cleaning roller. As a material for such an elastic body, a conventionally known rubber such as silicone rubber or urethane rubber, a foam or a foam covered with a resin film is preferable.

Surface resistivity of cleaning roller (Ω)
Is normal temperature and humidity (temperature 26 ° C, relative humidity 50%), Mitsubishi Yuka's Hiresta IP (MPC-HT250), H
It is a value measured using an A probe at an applied voltage of 10 V and a measurement time of 10 seconds.

The thickness of the conductive or semi-conductive elastic layer depends on the surface resistivity and hardness of the material, but is generally about 0.
It is desirable to set the distance between 5 mm and 50 mm from the viewpoint of securing an appropriate resistance value and nip width. The volume resistivity of the roller material is preferably in the range of 10 ² Ωcm to ^{10 10} Ωcm.

The cleaning roller is preferably conductive or semiconductive and has a surface resistivity in the range of 10 ² Ω to ^{10 10} Ω. If the resistivity is lower than 10 ² Ω,
Banding due to discharge is likely to occur. Also,
If it is higher than 10 ¹⁰ Ω, the potential difference from the photoconductor becomes low, and cleaning failure tends to occur.

The cleaning roller preferably rotates so that its abutting portion moves in the same direction as the surface of the photosensitive member. When the contact portion moves in the opposite direction, when excess toner is present on the surface of the image bearing member, the toner removed by the cleaning roller may spill and stain the recording paper or the apparatus.

When the photoconductor and the cleaning roller move in the same direction as described above, the surface speed ratio of the two is preferably in the range of 0.5: 1 to 2: 1. Outside this range, the speed difference between the two becomes large,
When foreign matter such as recording paper is caught between the photoconductor and the cleaning roller, the photoconductor may be damaged.

The hardness of the cleaning roller is 5 ° to 60 °
Is preferable, and a range of 10 ° to 50 ° is particularly preferable. If the hardness is less than 5 °, the durability is insufficient and the hardness is 60.
If it exceeds 0, it becomes difficult to secure the contact width between the photoconductor and the cleaning roller, which is necessary for cleaning, and the surface of the photoconductor is easily scratched. In addition,
The hardness of the cleaning roller is a value measured by an Asker C hardness meter (load 300 gf) on the elastic body after being molded into the roller.

The contact width between the photosensitive member and the cleaning roller is preferably 0.2 mm to 5 mm, and 0.5 mm to 3 m.
The range of m is particularly preferable. If the contact width is less than 0.2 mm, the cleaning force is insufficient, and if it exceeds 5 mm, the photosensitive member is likely to be scratched by rubbing.

A bias voltage is applied from the power source 126H to the bias voltage cleaning roller 126C. The bias voltage is applied to the photoconductor 12
The voltage is a voltage for electrostatically attracting and removing the toner adhering to the surface 1 of the cleaning roller 126C to the cleaning roller 126C, which has a polarity opposite to the charging polarity of the toner. In this embodiment using the negatively charged toner, the bias voltage is positive. A constant current power supply is used as the power supply 126H that applies the bias voltage.

The constant current power source here is a power source configured to control the output voltage according to the resistance between the cleaning roller and the photoconductor so that a constant current value is always output.

After the transfer, there is an electrostatic charge on the photoconductor 121, and the potential on the photoconductor 121 is not uniform. However, by applying a bias voltage from the constant current power source to the cleaning roller 126C, the toner is electrostatically charged. When attracted to the cleaning roller 126C, a substantially constant electric field that is not affected by the potential on the photoconductor 121 is formed between the surface of the photoconductor 121 and the surface of the cleaning roller 126C, and a uniform cleaning effect is obtained. , An excellent cleaning effect can be achieved. Further, since a large potential difference is not locally generated, discharge is unlikely to occur.

The applied current value is 1 μA to 50 μ in absolute value.
The range of A is preferable. If it is smaller than 1 μA, the cleaning effect may be insufficient, and if it is larger than 50 μA, discharge or the like is likely to occur. Although this value varies depending on the type of the photoconductor and the resistance value of the cleaning roller, the organic photoconductor is dispersed in a resin to have a thickness of 10 μm to 3 μm.
The surface resistivity is 1 with the organic photoreceptor on which the photosensitive layer of 0 μm is formed.
When using a cleaning roller of 0 ² Ω to ^{10 10} Ω, the range of 5 μA to 40 μA is preferable.

Removing Means As shown in FIG. 2, it is preferable to remove a removed substance such as toner transferred from the photoconductor 121 to the cleaning roller 126C by bringing a scraper 126D as a removing means into contact with the cleaning roller 126C.

As the scraper 126D, an elastic plate such as a phosphor bronze plate, a polyethylene terephthalate plate or a polycarbonate plate is used, and the tip thereof is the cleaning roller 1.
The cleaning roller 126C may be contacted by any of a trail method that forms an acute angle on the uncleaned side of 26C or a counter method that the tip forms an acute angle on the cleaned side of the cleaning roller 126C.

In addition to the scraper, a roller or a brush can be used as the removing means. The toner collected by the scraper 126D, together with the toner collected by the cleaning blade 126A,
It is put into the developing device 123 by a recycling means (not shown) and reused. A plurality of removing means such as the scraper 126D may be provided. When the bias voltage is increased and the cleaning force of the cleaning roller 126C is increased, the toner is electrostatically strong and the cleaning roller 12C is strong.
Since it adheres to 6C, it is preferable to collect it with a plurality of scrapers.

Next, the organic photoreceptor of the present invention will be described. In the present invention, the photoconductor is an electrophotographic photoconductor used for electrophotographic image formation, and among them, an organic electrophotographic photoconductor (organic photoconductor) is preferable. The organic photoconductor means an electrophotographic photoconductor composed of an organic compound having at least one of a charge generation function and a charge transport function, which are indispensable for the construction of the electrophotographic photoconductor. It includes all known organic electrophotographic photoreceptors such as a photoreceptor formed of a substance or an organic charge transport material, a photoreceptor formed of a polymer complex having a charge generation function and a charge transport function.

The constitution of the organic photoconductor used in the present invention will be described below. Conductive Support As the conductive support used in the photoreceptor of the present invention, either a sheet shape or a cylindrical shape may be used, but in order to design the image forming apparatus compactly, the cylindrical conductive support is used. Is preferred.

The cylindrical conductive support of the present invention means a cylindrical support required to form an image endlessly by rotating, and has a straightness of 0.1 mm or less and a shake of 0.1 mm or less. Conductive supports in the range are preferred. When the circularity and the shake range are exceeded, good image formation becomes difficult.

As the conductive material, a metal drum of aluminum, nickel or the like, a plastic drum on which aluminum, tin oxide, indium oxide or the like is deposited, or a paper / plastic drum coated with a conductive substance can be used. It is preferable that the conductive support has a specific resistance of 10 ³ Ωcm or less at room temperature.

The conductive support used in the present invention may have a surface on which a pore-treated alumite film is formed. The alumite treatment is usually carried out in an acidic bath of chromic acid, sulfuric acid, oxalic acid, phosphoric acid, boric acid, sulfamic acid, etc., but anodizing treatment in sulfuric acid gives the most preferable result. In the case of anodizing treatment in sulfuric acid, it is preferable that the sulfuric acid concentration is 100 to 200 g / l, the aluminum ion concentration is 1 to 10 g / l, the liquid temperature is around 20 ° C., and the applied voltage is about 20 V. It is not limited. The average thickness of the anodized film is usually 2
It is preferably 0 μm or less, and particularly preferably 10 μm or less.

Intermediate Layer In the present invention, an intermediate layer having a barrier function may be provided between the conductive support 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 and 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 having 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 more preferably, it is photosensitive. 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. Further, in the case of a photoreceptor having a charge transport layer as a surface layer, a polycarbonate that is resistant to mechanical abrasion is preferable, and as such a polycarbonate, a polycarbonate having an average molecular weight of 40,000 or more is preferable. 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.

Protective Layer Various resin layers can be provided as a protective layer of the photoreceptor. In particular, by providing a crosslinked resin layer, the organic photoreceptor of the present invention having high mechanical strength can be obtained.

The solvent or dispersion medium used for forming the intermediate layer, photosensitive layer, protective layer and the like of the present invention includes n-butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N-. Dimethylformamide, acetone, methyl ethyl ketone, methyl isopropyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, dichloromethane, 1,2-dichloroethane, 1,
2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethane, tetrahydrofuran, dioxolane, dioxane, methanol, ethanol, butanol, isopropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl Cellosolve etc. are mentioned. The present invention is not limited to these, but dichloromethane, 1,2-dichloroethane, methyl ethyl ketone and the like are preferably used. Further, these solvents can be used alone or as a mixed solvent of two or more kinds.

Next, as a coating processing method for producing the organic photoreceptor used in the present invention, a coating processing method such as dip coating, spray coating or circular amount regulation type coating is used. It is preferable to use a coating processing method such as spray coating or circular amount regulation type (a circular slide hopper type is a typical example) coating in order to prevent the lower layer film from being dissolved as much as possible and to achieve uniform coating processing. . For the protective layer of the present invention, it is most preferable to use the circular amount regulating type coating processing method. The circular amount control type coating is described in detail, for example, in JP-A-58-189061.

Next, the toner used in the present invention will be described. The toner is preferably a polymerized toner in which the particle size distribution of individual toner particles and the shape are relatively uniform. Here, the polymerized toner means a toner obtained by forming a resin of a binder for a toner and forming a toner shape by polymerizing a raw material monomer of the binder resin and subsequent chemical treatment. More specifically, it means a toner obtained through a polymerization reaction such as suspension polymerization and emulsion polymerization and, if necessary, a fusion process of particles that are carried out after the polymerization reaction.

As the polymerized toner used in the cleaning device using the cleaning blade of the present invention, a toner having a specific shape is preferable. The polymerized toner that can be preferably used in the present invention will be described below.

Preferred polymerized toners applicable to the present invention are toner particles having a shape factor in the range of 1.2 to 1.6 of 65% by number or more, and a variation coefficient of the shape factor of 1.
To use a toner that is 6% or less. It has been found that, even when such a polymerized toner is used, the vibration of the cleaning blade can be stabilized in the present invention, and excellent cleaning performance is exhibited.

Further, the vibration stability of the cleaning blade varies depending on the particle size of the toner particles, and the smaller the particle size, the higher the adhesion to the image carrier, so that the vibration is apt to become excessive, and the toner is small. Have a high probability of slipping through the cleaning blade. However, when the toner particle size is large, such slip-through is reduced,
There is a problem that image quality such as resolution is deteriorated.

As a result of the examination from the above viewpoints, by using a toner in which the variation coefficient of the shape factor of the toner is 16% or less and the variation coefficient of the number particle size distribution of the toner is 27% or less, It has been found that it is possible to form a high-quality image over a long period of time with excellent cleaning properties and fine line reproducibility.

Further, by using toner particles having no corners of 50% by number or more and controlling the number variation coefficient in the number particle size distribution to be 27% or less, excellent cleaning property, fine line reproducibility and high quality are obtained. The image quality can be formed over a long period of time.

The shape factor of the toner of the present invention is represented by the following formula and represents the degree of roundness of toner particles.

Shape factor = ((maximum diameter / 2) ² × π) / projected area Here, the maximum diameter means the parallel line when the projected image of toner particles on a plane is sandwiched by two parallel lines. Refers to the width of the particles at which the interval is maximum. The projected area means the area of the projected image of the toner particles on the plane.

In the present invention, this shape factor is determined by taking a photograph of toner particles magnified 2000 times with a scanning electron microscope, and then using this photograph, "SCANNING" is taken.
It was measured by analyzing a photographic image using "IMAGE ANALYZER" (manufactured by JEOL Ltd.). At this time, the shape factor of the present invention was measured by the above calculation formula using 100 toner particles.

The preferred polymerized toner of the present invention is that the number of toner particles having a shape factor of 1.2 to 1.6 is 65% by number or more, and more preferably 7
It is 0% by number or more.

When the number of toner particles having the shape factor in the range of 1.2 to 1.6 is 65% by number or more, the adhesive force between the photoconductor and the toner is reduced and the toner passes through the cleaning blade. Hard to do. Further, the toner particles are less likely to be crushed, the contamination on the photoconductor is reduced, and the toner cleaning property is stabilized.

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

The variation coefficient of the shape factor of the polymerized toner preferably used in the present invention is calculated from the following formula.

Coefficient of variation = [S / K] × 100 (%) [In the formula, S represents the standard deviation of the shape factor of 100 toner particles, and K represents the average value of the shape factor. The variation coefficient of the shape factor is 16% or less, preferably 14% or less. When the variation coefficient of the shape coefficient is 16% or less, the residual toner after transfer is reduced and the toner does not easily slip through the cleaning blade. In addition, the charge amount distribution becomes sharp and the image quality is improved.

In order to uniformly control the shape factor and the variation coefficient of the shape factor of the toner without extremely lot-to-lot variation, the toner is formed in the steps of polymerizing, fusing and controlling the shape of resin particles (polymer particles). An appropriate process end time may be determined while monitoring the characteristics of certain toner particles (colored particles).

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

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

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

The number variation coefficient in the number particle size distribution of toner is calculated from the following formula. Number variation coefficient = [S / Dn] × 100 (%) [In the formula, S represents the standard deviation in the number particle size distribution, and D
n indicates a number average particle diameter (μm). The toner number variation coefficient is 27% or less, preferably 25% or less. When the number variation coefficient is 27% or less, the transfer residual toner is reduced, and the toner does not easily slip through the cleaning blade. Further, the charge amount distribution becomes sharp, the transfer efficiency is improved, and the image quality is improved.

The method of controlling the number variation coefficient is not particularly limited. For example, a method of classifying toner particles by wind force can be used, but classification in a liquid is effective for reducing the number variation coefficient. As a method of classifying in this liquid, there is a method of controlling the number of revolutions and separately collecting and preparing toner particles according to the difference in sedimentation speed caused by the difference in toner particle diameter.

Particularly when the toner is produced by the suspension polymerization method, the classification operation is indispensable to keep the number variation coefficient in the number particle size distribution at 27% or less. In the suspension polymerization method,
Before the polymerization, it is necessary to disperse the polymerizable monomer into an oil droplet having a desired size as a toner in an aqueous medium. That is, the large oil droplets of the polymerizable monomer are repeatedly mechanically sheared by a homomixer or a homogenizer to reduce the oil droplets to the size of toner particles. In the method of different shearing, the number particle size distribution of the obtained oil droplets becomes wide, and therefore,
The toner obtained by polymerizing this also has a wide particle size distribution. For this reason, classification operation is essential.

The toner particles having no corners are toner particles that do not substantially have protrusions where electric charges are concentrated or protrusions that are easily worn by stress, that is, as shown in FIG. In addition, when the major axis of the toner particles T is L, a circle C having a radius (L / 10) is in contact with the peripheral line of the toner particles T at one point, and when the inside is rolled, the circle C When the toner does not substantially protrude outside the toner T, it is referred to as “cornerless toner particles”. The term “when substantially not protruding” means a case where there is one or less protrusions with protruding circles. Also, "long diameter of toner particles"
The term "means the width of a particle in which the distance between the parallel lines is maximum when the projected image of the toner particle on the plane is sandwiched by two parallel lines. Note that FIGS. 3B and 3C respectively show projection images of toner particles having corners.

The cornerless toner was measured as follows. First, an enlarged photograph of toner particles is taken with a scanning electron microscope and further enlarged to obtain a photographic image at 15,000 times. Then, the presence or absence of the above-mentioned corner is measured for this photographic image. This measurement was performed on 100 toner particles.

In the toner of the present invention, the proportion of toner particles having no corners is 50% by number or more, preferably 70% by number or more. When the ratio of the toner particles having no corners is 50% by number or more, the generation of fine particles is less likely to occur due to the stress with the developer transport member and the like,
It is possible to prevent the presence of toner with excessive adhesion to the surface of the developer transport member, suppress contamination of the developer transport member, and make the charge amount sharp. Further, the toner particles that are easily worn or broken and the toner particles having a portion where the electric charge is concentrated are reduced, the charge amount distribution becomes sharp, the chargeability becomes stable, and good image quality can be formed for a long time.

The method for obtaining the toner without corners is not particularly limited. For example, as described above as a method of controlling the shape factor, a method of spraying toner particles in a hot air flow, a method of repeatedly applying mechanical energy due to impact force in a gas phase, or a method of dissolving toner It can be obtained by adding it to a solvent that does not contain it and imparting a swirling flow.

Further, in the polymerization toner formed by associating or fusing resin particles, the surface of the fused particles has many irregularities at the step of stopping the fusion, and the surface is not smooth, but in the shape controlling step. The toner having no corners can be obtained by appropriately adjusting the conditions such as the temperature, the rotation speed of the stirring blade, and the stirring time. These conditions vary depending on the physical properties of the resin particles, but for example, by setting the glass transition temperature of the resin particles or higher to a higher rotation speed, the surface becomes smooth and toner without corners can be formed.

The particle size of the toner of the present invention is preferably 3-8 μm in number average particle size. When the toner particles are formed by a polymerization method, this particle size can be controlled by the concentration of the aggregating agent, the amount of the organic solvent added, the fusing time, and the composition of the polymer itself.

By having the number average particle diameter of 3 to 8 μm, it is possible to reduce the presence of toner having excessive adhesion to the developer conveying member, toner having low adhesion, etc. in the fixing step, and to improve the developability. It can be stabilized for a long period of time, the transfer efficiency is improved, the halftone image quality is improved, and the image quality of fine lines, dots, etc. is improved.

As the polymerized toner preferably used in the present invention, when the particle diameter of the toner particles is D (μm), the natural logarithm lnD is plotted on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23. in histogram showing the particle size distribution of number criteria, the relative frequency of the toner particles contained in the modal class (m _1), the relative frequency of the toner particles contained in the following frequent the rank of the modal class (m ₂ ) And (M) is 7
The toner is preferably 0% or more.

When the sum (M) of the relative frequency (m ₁ ) and the relative frequency (m ₂ ) is 70% or more, the dispersion of the particle size distribution of the toner particles becomes narrow, so that the toner is used in the image forming process. By using it, the occurrence of selective development can be surely suppressed.

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

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

Among the methods of controlling the shape factor, the polymerized toner is preferable because it is simple as a production method, and the surface uniformity is excellent as compared with the pulverized toner.

The toner of the present invention is obtained by emulsion polymerization of a monomer in a suspension polymerization method or in a liquid containing an emulsion containing necessary additives.
It can be manufactured by a method in which finely divided polymer particles are produced, and thereafter, an organic solvent, an aggregating agent and the like are added and associated. At the time of association, a method of preparing by mixing with a dispersion liquid such as a release agent or a colorant necessary for the constitution of the toner to allow association, or dispersing a toner constituent component such as a release agent or a colorant in a monomer Then, a method of emulsion polymerization may be used. Here, the association means that a plurality of resin particles and colorant particles are fused.

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

That is, various constituent materials such as a colorant and, if necessary, a release agent, a charge control agent, and a polymerization initiator are added to the polymerizable monomer, and a homogenizer, a sand mill, a sand grinder, and an ultrasonic dispersion are added. Various constituent materials are dissolved or dispersed in the polymerizable monomer by a machine or the like. The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in an oil droplet having a desired size as a toner in a water-based medium containing a dispersion stabilizer by using a homomixer or a homogenizer. Then, the stirring mechanism is transferred to a reaction device which is a stirring blade described later and heated to allow the polymerization reaction to proceed. After the completion of the reaction, the dispersion stabilizer is removed, filtered, washed, and dried to prepare a toner.

Further, as a method for producing the toner of the present invention, a method of preparing by associating or fusing resin particles in an aqueous medium can be mentioned. This method is not particularly limited, but for example, JP-A-5-26
The methods shown in JP-A-5252, JP-A-6-329947 and JP-A-9-15904 can be mentioned. That is, a method of associating a plurality of resin particles and dispersed particles of a constituent material such as a colorant, or a plurality of fine particles composed of a resin and a colorant, in particular, after dispersing these in water with an emulsifier, the critical aggregation concentration At the same time as salting out by adding the aggregating agent above, while gradually growing the particle size while forming fused particles by heat fusion above the glass transition temperature of the polymer itself formed, the target particle size and After that, a large amount of water is added to stop the particle size growth, and the surface of the particles is smoothed while heating and stirring to control the shape, and the particles are heated and dried in a fluid state in a water-containing state. Can be formed. Here, an organic solvent that is infinitely soluble in water may be added simultaneously with the coagulant.

Those usable as the polymerizable monomer constituting the resin include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene and 3,4- Dichlorostyrene,
p-phenylstyrene, p-ethylstyrene, 2,4-
Dimethyl styrene, p-tert-butyl styrene, p
-N-hexyl styrene, pn-octyl styrene,
pn-nonylstyrene, pn-decylstyrene, p
Styrene or styrene derivative such as -n-dodecyl styrene, methyl methacrylate, ethyl methacrylate,
N-butyl methacrylate, isopropyl methacrylate,
Methacrylate ester derivatives such as isobutyl methacrylate, t-butyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, lauryl methacrylate, phenyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate. , Methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, isobutyl acrylate,
Acrylic ester derivatives such as n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate and phenyl acrylate, olefins such as ethylene, propylene and isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide , Vinyl fluoride, vinylidene fluoride, and other halogen-based vinyls, vinyl propionate, vinyl acetate, vinyl benzoate, and other vinyl esters, vinyl methyl ether, vinyl ethyl ether, and other vinyl ethers, vinyl methyl ketone, vinyl ethyl ketone , Vinyl ketones such as vinyl hexyl ketone, N-vinyl compounds such as N-vinyl carbazole, N-vinyl indole and N-vinyl pyrrolidone, vinyl compounds such as vinyl naphthalene and vinyl pyridine, acrylonitrile, Acrylonitrile, there are acrylic acid or methacrylic acid derivatives such as acrylamide. These vinyl monomers can be used alone or in combination.

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

Further, divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate,
It is also possible to use a polyfunctional vinyl such as neopentyl glycol diacrylate to form a resin having a crosslinked structure.

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

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

Examples of the dispersion stabilizer include tricalcium phosphate, magnesium phosphate, zinc phosphate, aluminum phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate. , Barium sulfate,
Examples thereof include bentonite, silica and alumina. Furthermore, polyvinyl alcohol, gelatin, methyl cellulose, sodium dodecylbenzene sulfonate, ethylene oxide adduct, higher alcohol sodium sulfate, and the like which are commonly used as surfactants can be used as the dispersion stabilizer.

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

The aggregating agent used is not particularly limited, but one selected from metal salts is preferably used. Specifically, monovalent metals such as salts of alkali metals such as sodium, potassium and lithium, divalent metals such as alkaline earth metal salts such as calcium and magnesium, divalent metals such as manganese and copper. Salt of
Examples thereof include salts of trivalent metals such as iron and aluminum, and specific salts include sodium chloride, potassium chloride, lithium chloride, calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate and the like. You can
These may be used in combination.

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

The addition amount of the aggregating agent may be a critical coagulation concentration or more, but is preferably 1.2 times or more the critical coagulation concentration.
It is more preferable to add 1.5 times or more.

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

The amount of the solvent that dissolves infinitely is 1 to 100% by volume with respect to the polymer-containing dispersion liquid to which the aggregating agent is added.
Is preferred.

In order to make the shape uniform, it is preferable to prepare colored particles, and after filtering, slurry in which 10% by mass or more of water is present is fluidized and dried. Those having a polar group in the polymer are preferred. It is considered that the reason for this is that since the existing water exerts an effect of swelling the existing water to some extent with respect to the polymer having the polar group, the homogenization of the shape is particularly likely to occur.

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

The colorant used in the toner of the present invention may be any carbon black, magnetic substance, dye, pigment or the like. Examples of carbon black include channel black, furnace black, acetylene black,
Thermal black, lamp black, etc. are used. Ferromagnetic metals such as iron, nickel, and cobalt as magnetic materials,
Alloys containing these metals, compounds of ferromagnetic metals such as ferrite and magnetite, alloys containing no ferromagnetic metals but exhibiting ferromagnetism by heat treatment, such as manganese-copper-
Aluminum, manganese-copper-tin, and other types of alloys called Heusler alloys, chromium dioxide, and the like can be used.

As the dye, C.I. I. Solvent Red 1, 49, 52, 58, 63, 111, 1
22, C.I. I. Solvent Yellow 19, 44, 7
7, ibid 79, ibid 81, ibid 82, ibid 93, ibid 98, ibid 10
3, 104, 112, 162, C.I. I. Solvent Blue 25, 36, 60, 70, 93, 9
5 and the like can be used, and a mixture thereof can also be used. As the pigment, C.I. I. Pigment Red 5,
48: 1, 53: 1, 57: 1, 122, 1
39, 144, 149, 166, 177, 1
78, ibid. 222, C.I. I. Pigment Orange 31, the same 43, C.I. I. Pigment Yellow 14, Same 17 and Same 9
3, 94, 138, C.I. I. Pigment Green 7, C.I. I. Pigment Blue 15: 3, 60 and the like, and a mixture thereof can also be used. The number average primary particle size varies depending on the type, but is generally about 10
About 200 nm is preferable.

The colorant may be added by adding the polymer particles prepared by the emulsion polymerization method at the stage of aggregating by adding an aggregating agent to color the polymer, or by polymerizing the monomer. It is possible to use a method in which a coloring agent is added and polymerized to obtain colored particles. When the colorant is added at the stage of preparing the polymer, it is preferable that the surface is treated with a coupling agent or the like so as not to hinder radical polymerizability.

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

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.

The particles of these charge control agents and fixability improvers have a number average primary particle diameter of 10 to 50 in a dispersed state.
It is preferably about 0 nm.

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

The reaction device for polymerized toner preferably used in the present invention will be described below. First, a reaction apparatus preferably used for producing a polymerized toner will be described.
4 and 5 are a perspective view and a sectional view, respectively, showing an example of a polymerized toner reaction device. In the reactor shown in FIGS. 4 and 5, a rotating shaft 3 is vertically provided at the center of a vertical cylindrical stirring tank 2 having a jacket 1 for heat exchange mounted on the outer periphery thereof, and stirring is performed on the rotating shaft 3. A lower stirring blade 40 arranged near the bottom surface of the tank 2 and a stirring blade 50 arranged further above are provided. The upper stirring blade 50 is
The stirring blades 40 located in the lower stage are arranged with a crossing angle α that precedes them in the rotational direction. In the case of producing the toner of the present invention, the crossing angle α is preferably less than 90 degrees (°). The lower limit of the intersection angle α is not particularly limited, but is preferably about 5 ° or more, and more preferably 10 ° or more. When three-stage stirring blades are provided, the intersecting angle α between adjacent stirring blades is preferably less than 90 degrees.

With such a structure, the medium is first stirred by the stirring blades 50 arranged in the upper stage, and a downward flow is formed. Then, the stirring blade 40 arranged in the lower stage accelerates the flow formed by the stirring blade 50 in the upper stage further downward, and the stirring blade 50 itself also forms a downward flow, so that the flow as a whole is reduced. It is estimated to accelerate and proceed. As a result, a basin having a large shear stress formed as a turbulent flow is formed, and it is presumed that the shape of the obtained toner particles can be controlled.

4 and 5, the arrow indicates the direction of rotation, 7 is the upper material charging port, 8 is the lower material charging port, and 9 is.
Is a turbulent flow forming member for making stirring effective.

Here, the shape of the stirring blade is not particularly limited, but it has a rectangular plate shape, a blade with a cutout, and a central portion with one or more holes, so-called slits. Things etc. can be used. Specific examples of these are shown in FIG. The stirring blade 5 shown in FIG.
a has no central hole, the stirring blade 5b shown in FIG. 6B has a large central hole 6b in the center, and the stirring blade 5c shown in FIG. 6C has a horizontally long central hole 6c (slit). ), The stirring blade 5d shown in FIG.
There is a (slit). Further, in the case of providing a three-stage stirring blade, even if the middle hole portion formed in the upper stirring blade and the middle hole portion formed in the lower stirring blade are different, they may be the same. It may be.

The gap between the upper and lower stirring blades having the above structure is not particularly limited, but it is preferable that there is a gap at least between the stirring blades. The reason for this is not clear, but it is considered that the stirring efficiency is improved because the flow of the medium is formed through the gap. However, the gap has a width of 0.5 to 50%, preferably a width of 1 to 30% with respect to the liquid surface height in a stationary state.

Further, the size of the stirring blade is not particularly limited, but the total height of all stirring blades is 50% to 100%, preferably 60% to 50% of the liquid surface height in a stationary state. 95
%.

On the other hand, in the case of the polymerized toner in which the resin particles are associated or fused with each other in the aqueous medium, the flow and temperature distribution of the medium in the reaction vessel at the fusion stage are controlled to further improve the shape after fusion. By controlling the heating temperature, stirring rotation number, and time in the control step, the shape distribution and shape of the entire toner can be arbitrarily changed.

That is, in the case of a polymerized toner in which resin particles are associated or fused, the flow in the reaction device is a laminar flow,
By using a stirring blade and a stirring tank that can make the internal temperature distribution uniform, by controlling the temperature, rotation speed, and time in the fusion process and shape control process, the desired shape factor and uniform A toner having a shape distribution can be formed. The reason for this is that when fusion is performed in a laminar flow-forming place, strong stress is not applied to particles (association or agglomerated particles) in which aggregation and fusion are progressing, and in a laminar flow in which the flow is accelerated, It is presumed that, as a result of the uniform temperature distribution in the stirring tank, the shape distribution of the fused particles becomes uniform. Furthermore, heating in the subsequent shape control process,
By stirring, the fused particles gradually become spherical and the shape of the toner particles can be arbitrarily controlled.

As the stirring tank used in the production of the polymerization toner in which the resin particles are associated or fused, the same one as in the suspension polymerization method can be used. In this case, it is necessary not to provide an obstacle such as a baffle plate that forms a turbulent flow in the stirring tank.

The shape of this stirring blade is also not particularly limited as long as it forms a laminar flow and does not form a turbulent flow, but it may be formed by a continuous surface such as the rectangular plate shown in FIG. 6 (a). What is formed is preferable, and may have a curved surface.

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

As the inorganic fine particles, it is preferable to use inorganic oxide particles such as silica, titania and alumina, and further, these inorganic fine particles are subjected to a hydrophobic treatment with a silane coupling agent or a titanium coupling agent. preferable. The degree of hydrophobic treatment is not particularly limited, but methanol wettability of 40 to 95 is preferable. Methanol wettability is an evaluation of wettability with respect to methanol. In this method, 50 ml of distilled water placed in a beaker with an internal volume of 200 ml was charged with inorganic fine particles to be measured in an amount of 0.
Weigh 2 g and add. Methanol is dripped slowly from a buret whose tip is dipped in the liquid, with slow stirring until the whole inorganic fine particles become wet. When the amount of methanol required to completely wet the inorganic fine particles is a (ml), the degree of hydrophobicity is calculated by the following formula.

Hydrophobicity = (a / (a + 50)) × 100 The addition amount of this external additive is 0.1 to 5% in the toner.
It is 0% by mass, preferably 0.5 to 4.0% by mass. Further, various external additives may be used in combination.

A fatty acid metal salt may be added as an external additive to the toner used in the present invention. Fatty acids and metal salts thereof include undecyl acid, lauric acid, tridecyl acid, dodecyl acid, myristic acid, palmitic acid, pentadecyl acid, stearic acid, heptadecyl acid, arachidic acid, montanic acid, oleic acid, linoleic acid, arachidonic acid, etc. And long-chain fatty acids thereof, and examples of the metal salt thereof include salts with metals such as zinc, iron, magnesium, aluminum, calcium, sodium and lithium. In the present invention, zinc stearate is particularly preferable. << Developer >> The toner used in the present invention may be a one-component developer or a two-component developer, but is preferably a two-component developer.

When used as a one-component developer, there is a method of using the toner as it is as a non-magnetic one-component developer, but normally, the toner particles contain magnetic particles of about 0.1 to 5 μm, and the magnetic one-component developer is used. Used as a developer. As a method of containing it, it is common to incorporate it in the non-spherical particles in the same manner as the colorant.

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, alloys of these metals with metals such as aluminum and lead are used as the magnetic particles of the carrier. Ferrite particles are particularly preferable. The volume average particle diameter of the magnetic particles is 15
˜100 μm, more preferably 25 to 60 μm.

The volume average particle diameter of the carrier is typically measured by a laser diffraction type particle size distribution measuring apparatus "HELOS" equipped with a wet disperser (SYMPATIC (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, and for example, styrene acrylic resin, polyester resin, fluorine resin, phenol resin, etc. can be used. it can.

To prepare the two-component developer, the toner and the carrier are mixed. The toner is mixed in a toner concentration of 2 to 10% by mass based on the developer.

The developing method according to the present invention is not particularly limited. Even in the contact development method in which development is performed in a state where the surface of the photoconductor and the developer layer are in contact with each other in the development area, the photoconductor and the developer layer are kept in the non-contact state in the development area, and an alternating electric field, etc. A non-contact developing method in which toner is caused to fly in the gap between the surface of the photoconductor and the developer layer by the action to develop the toner may be used.

[0168]

EXAMPLES Preparation of Photoreceptor and Developer The preparation of the photoreceptor and developer used in the following examples will be described below.

Preparation of photoconductor P1 The photoconductor P1 was manufactured as follows.

<Intermediate Layer> Titanium chelate compound (TC-750: manufactured by Matsumoto Pharmaceutical Co., Ltd.) 30 g Silane coupling agent (KBM-503: manufactured by Shin-Etsu Chemical Co., Ltd.) 17 g 2-propanol 150 ml It was provided on an aluminum drum substrate that was cut to have a thickness of 0.4 μm, and a dry film thickness of 0.
It was applied so as to have a thickness of 5 μm.

<Charge Generation Layer> Y-type titanyl phthalocyanine 60 g Silicone-modified butyral resin (X-40-1211: manufactured by Shin-Etsu Chemical Co., Ltd.) 700 g 2-butanone 2000 ml were mixed and dispersed for 10 hours using a sand mill, and the charge generation layer was mixed. Was prepared. This coating solution was applied onto the intermediate layer by a dip coating method to form a charge generation layer having a dry film thickness of 0.2 μm.

<Charge Transport Layer> Charge transport material (4-methoxy-4 ′-(4-methyl-α-phenylstyryl) triphenylamine) 200 g Polycarbonate (TS2050: manufactured by Teijin Chemicals Ltd.) 300 g Dichloromethane 2000 ml was mixed, It melt | dissolved and prepared the charge transport layer coating liquid. This coating solution was applied onto the charge generation layer by a dip coating method to form a charge transport layer having a dry film thickness of 20 μm, and a photoconductor P1 was produced.

Production of Photoreceptor P2 The charge transport layer was produced in the same manner as the photoreceptor P1.

<Resin Layer> Methyltrimethoxysilane 150 g Phenyltrimethoxysilane 30 g CTM (Compound A below) 45 g Antioxidant (Compound B below) 1 g 2-Propanol 225 g 2% Acetic acid 106 g Trisacetylacetonatoaluminum 4 g Colloidal silica ( 10% of a 30% methanol solution (manufactured by Nissan Chemical Industries, Ltd.) was mixed to prepare a coating liquid for a resin layer. A resin layer having a dry film thickness of 2.5 μm is formed on this charge transport layer by a circular amount regulation type coating device on the charge transport layer, and the resin layer is cured by heating at 110 ° C. for 1 hour to form a siloxane resin layer having a crosslinked structure. Then, a photoconductor P2 was produced.

[0175]

[Chemical 1]

Preparation of developer The toner used in the examples was prepared as follows.

Preparation of Toners T1 and T2 (Example of Emulsion Polymerization Method) 0.90 kg of sodium n-dodecyl sulfate and pure water 10.
Add 0 L and dissolve with stirring. To this solution, legal 330
After gradually adding 1.20 kg of R (carbon black manufactured by Cabot Corporation) and stirring well for 1 hour, the mixture was continuously dispersed for 20 hours using a sand grinder (medium type disperser). This is designated as "colorant dispersion liquid 1". Further, a solution composed of 0.055 kg of sodium dodecylbenzenesulfonate and 4.0 L of ion-exchanged water is referred to as "anionic surfactant solution A".

0.014 kg of nonylphenol polyethylene oxide adduct of 0.014 kg and ion-exchanged water of 4.0 L
The solution consisting of is referred to as "Nonionic surfactant solution B".
223.8 g of potassium persulfate, 12.0 L of ion-exchanged water
The solution dissolved in was designated as "initiator solution C".

In a 100 L GL (glass lining) reaction kettle equipped with a temperature sensor, a cooling pipe, and a nitrogen introducing device, W
AX emulsion (polypropylene emulsion having a number average molecular weight of 3000: number average primary particle size = 120 nm / solid content concentration = 29.9%) 3.41 kg and "anionic surfactant solution A" and the total amount and "nonionic surfactant solution B" Add the whole amount and start stirring. Next, deionized water 4
Add 4.0 L.

When heating was started and the liquid temperature reached 75 ° C., the entire amount of “initiator solution C” was added dropwise. Then, while controlling the liquid temperature to 75 ° C ± 1 ° C, styrene 1
2.1 kg, n-butyl acrylate 2.88 kg, methacrylic acid 1.04 kg and t-dodecyl mercaptan 54
8 g and is added dropwise. After the dropping was completed, the liquid temperature was raised to 80 ° C. ± 1 ° C., and the mixture was heated and stirred for 6 hours. Then, the liquid temperature is cooled to 40 ° C. or lower, stirring is stopped, and the mixture is filtered with a pole filter to obtain “latex-A”.

The resin particles in Latex-A had a glass transition temperature of 57 ° C., a softening point of 121 ° C., a molecular weight distribution of weight average molecular weight = 127,000, and a weight average particle diameter of 12.
It was 0 nm.

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

Potassium persulfate (manufactured by Kanto Chemical Co., Inc.) 200.
A solution prepared by dissolving 7 g in 12.0 L of ion-exchanged water is referred to as "initiator solution F".

In a 100 L GL reaction kettle equipped with a temperature sensor, a cooling tube, a nitrogen introducing device, and a comb-shaped baffle, a WAX emulsion (polypropylene emulsion having a number average molecular weight of 3000: number average primary particle diameter = 120 nm / solid content concentration 29.9). %) 3.41 kg, the total amount of “anionic surfactant solution D” and the total amount of “nonionic surfactant solution E” are added, and stirring is started. Next, ion-exchanged water 44.0L
Throw in. When heating is started and the liquid temperature reaches 70 ° C., “initiator solution F” is added. Then, a solution prepared by previously mixing 11.0 kg of styrene, 4.00 kg of n-butyl acrylate, 1.04 kg of methacrylic acid and 9.02 g of t-dodecyl mercaptan was added dropwise. After the dropping was completed, the liquid temperature was controlled at 72 ° C. ± 2 ° C., and the mixture was heated and stirred for 6 hours. Furthermore, the liquid temperature was raised to 80 ° C. ± 2 ° C., and the mixture was heated and stirred for 12 hours. The liquid temperature is cooled to 40 ° C. or lower and stirring is stopped. After filtering with a pole filter, this filtrate was designated as "latex-B".

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

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

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

100 L of S equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a particle size and shape monitoring device.
In a US reactor, latex-A = 2 prepared above
0.0 kg, latex-B = 5.2 kg, colorant dispersion 1 = 0.4 kg, and ion-exchanged water 20.0 kg are added and stirred. Then, the mixture was heated to 40 ° C., sodium chloride solution G, isopropanol (Kanto Chemical Co., Ltd.) 6.00 k
g, and nonionic surfactant solution H are added in this order. Then, after leaving it for 10 minutes, the temperature rise is started and the liquid temperature becomes 8
The temperature is raised to 5 ° C. in 60 minutes, and heated and stirred at 85 ± 2 ° C. for 0.5 to 3 hours to grow the particle size while salting out / fusing.
Next, 2.1 L of pure water is added to stop grain size growth.

5.0 kg of the fused particle dispersion prepared above was placed in a 5 L reaction vessel equipped with a temperature sensor, a cooling pipe, a particle size and shape monitoring device, and a liquid temperature of 85 ° C.
The shape was controlled by heating and stirring at ± 2 ° C for 0.5 to 15 hours. Then, the temperature is cooled to 40 ° C. or lower and stirring is stopped. Next, using a centrifuge, classification is performed in the liquid by a centrifugal sedimentation method, and the mixture is filtered through a sieve having an opening of 45 μm to obtain the filtrate as an association liquid. Then, using a Nutsche filter, wet cake-like non-spherical particles were collected from the association liquid by filtration. afterwards,
It was washed with ion-exchanged water.

The non-spherical particles were dried at a suction temperature of 60 ° C. using a flash jet dryer, and then at a temperature of 60 ° C. using a fluidized bed dryer. To 100 parts by mass of the obtained colored particles, 1 part by mass of silica fine particles and 0.1 part by mass of zinc stearate were externally added and mixed by a Henschel mixer to obtain a toner by an emulsion polymerization association method as shown in the table below. In the monitoring of the salting out / fusion step and the shape control step, the variation coefficient of the shape and the shape coefficient is controlled by controlling the stirring rotation speed and the heating time, and further the particle size and the particle size distribution are determined by the in-liquid classification. The toner T1 and the toner T2 shown in Table 1 were obtained by adjusting the variation coefficient of

Preparation of Toner T3 (Example of Suspension Polymerization Method) Styrene = 165 g, n-butyl acrylate = 35
g, carbon black = 10 g, di-t-butylsalicylic acid metal compound = 2 g, styrene-methacrylic acid copolymer = 8 g, paraffin wax (mp = 70 ° C.) = 20
g was heated to 60 ° C., uniformly dissolved and dispersed at 12000 rpm in a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), and 2,2′-azobis (2,4-valeronitrile) was added as a polymerization initiator thereto. ) = 10 g was added and dissolved to prepare a polymerizable monomer composition. Then, 450 g of a 0.1 M sodium phosphate aqueous solution was added to 710 g of ion-exchanged water, and the mixture was stirred at 13,000 rpm with a TK homomixer to 1.0.
68 g of M calcium chloride was gradually added to prepare a suspension in which tricalcium phosphate was dispersed. The above polymerizable monomer composition was added to this suspension, and the mixture was mixed with a TK homomixer for 10 minutes.
The polymerizable monomer composition was granulated by stirring at 000 rpm for 20 minutes. Then, using a reaction device (intersection angle α is 45 °) having a structure of a stirring blade as shown in FIG.
The reaction was carried out at 95 ° C for 5 to 15 hours. Tricalcium phosphate was dissolved and removed with hydrochloric acid, and then classified in the liquid by a centrifugal sedimentation method using a centrifuge, followed by filtration, washing and drying. To 100 parts by mass of the obtained colored particles,
1 part by mass of silica fine particles and 0.1 part by mass of zinc stearate were externally added and mixed by a Henschel mixer to obtain a toner by a suspension polymerization method.

By monitoring during the polymerization, the liquid temperature, the stirring rotation number, and the heating time were controlled to control the variation coefficient of the shape and the shape factor, and further the classification in the liquid to change the particle diameter and the particle size distribution. The coefficient was adjusted to obtain a toner T3 shown in Table 1 below.

[0193]

[Table 1]

Preparation of Developer 1 0.4 parts of hydrophobic silica particles (R805: manufactured by Nippon Aerosil Co., Ltd.) having an average particle diameter of 12 nm as external additives, and 100 parts of toner T1 described above, titania particles (T805: Nippon Aerosil). (Manufactured by the same company) was mixed and mixed with a Henschel mixer at room temperature for 10 minutes at a peripheral speed of a stirring blade of 40 (m / sec) to obtain a negatively chargeable toner. The adhesion rate of this toner was 45%.

A developer 1 having a toner concentration of 5% was prepared by mixing a ferrite carrier coated with a silicone resin and having a volume average particle diameter of 60 μm with the above toner.

Preparation of Developers 2 and 3 Developer 2 was prepared in the same manner except that toner T2 was used instead of toner T1 in the preparation of developer 1 described above.
A developer 3 was prepared in the same manner except that the toner T3 was used instead of the toner T1.

Example 1 In the following example, an image was formed using an image forming apparatus having processing means for charging, exposing, developing, transferring, fixing and cleaning as shown in FIGS.

The negatively chargeable OP is used as the present photoreceptor.
A negative electrostatic latent image was formed on the photoconductor using C photoconductors P1 and P2, and a toner image was formed on the photoconductor by reversal development using the developers 1 to 3 of the negatively charged toner. The moving speed of this photosensitive member was 370 mm / sec in terms of linear speed.

The conditions of the embodiment using the cleaning device according to claim 1 will be described below. Conditional structure of cleaning blade: As shown in FIG. 2, a thin metal plate member and a cleaning blade were attached to a supporting member. The free length a of the cleaning blade and the free length b of the thin metal plate member are shown in Tables 2 and 3.
It was changed as described in. However, in order to make the photoconductor and the cleaning blade conform to each other before the start of image formation, setting powder was sprayed on the photoconductor and the cleaning blade, and the photoconductor was rotated for 1 minute.

Cleaning conditions in Table 2 Cleaning blade contact angle: 20 ° Cleaning blade load (N / m): 25 N / m Cleaning blade: Thickness t ₁ : 2 mm, manufactured by Hokushin Kogyo Co., Ltd. (hardness 70 °, repulsion) Elasticity 60%) Metal thin plate member: SUS304, thickness t ₂ : 0.05 mm Photoreceptor: P1 Developer: 1 (toner: T1) Cleaning conditions in Table 3 Cleaning blade contact angle: 20 ° Cleaning blade load (N / m): 18 N / m Cleaning blade: Thickness t ₁ : 2 mm, manufactured by Hokushin Kogyo Co., Ltd. (hardness 67 °, rebound resilience 50%) Metal thin plate member: SUS304, thickness t ₂ : 0.02 mm Photoreceptor: P2 developer: 2 (toner: T2) consists cleaning roller conductive foamed urethane, the surface resistivity of 10 ³ Omega, click made of an elastic roller having a hardness 30 ° An over training roller was contacted so that the contact width 2mm a urethane wrapped (thickness 25 mm) formed roller so that the φ16mm the metal shaft of φ6mm the photoreceptor.

The contact portion moves in the forward direction with respect to the photoconductor at a peripheral speed ratio of 1: 1. 20μA with constant current power supply for bias voltage cleaning roller
Current was supplied and a positive bias voltage was applied.

Removal means Two scrapers made of SUS were brought into contact with the cleaning roller by a counter method.

Conditions of Photoreceptor and Developer Conditions of Table 2 Photoreceptor: P1 Developer: 1 (toner: T1) Conditions of Table 3 Photoreceptor: P2 Developer: 2 (toner: T2) Under environmental conditions, 200,000 images were formed and evaluated.

A. At 100,000 to 200,000 sheets, normal temperature and humidity (temperature 20 ° C, relative humidity 50%) b. From 0 to 100,000 sheets, high temperature and high humidity (temperature 30 ° C., relative humidity 80%) Evaluation items and evaluation criteria for this image formation are shown below. The evaluation results are shown in Tables 2 and 3.

Evaluation Items and Evaluation Criteria Blade turn-up (displayed in blanks in the table) ○: No blade turn-up up to 200,000 sheets △: No blade turn-up up to 100,000 sheets ×: Blade turn-up occurred under 100,000 sheets (After 100,000 and 200,000 copies have been copied, 10 copies are continuously made on A3 paper, and it is judged by whether or not toner slippage has occurred in the solid white area, and it is displayed as slippery in the table.): Up to 200,000 sheets of toner slippage No filming due to toner loss △: No filming due to toner slipping up to 100,000 sheets ×: Filming occurs due to toner slipping through less than 100,000 sheets Blade squeal Abnormal noise generated due to abnormal friction between cleaning blade and photoconductor The occurrence of this abnormal sound was evaluated.

◯: No blade squealing up to 200,000 sheets △: No blade squealing up to 100,000 sheets ×: Blade squealing occurs at less than 100,000 sheets Image unevenness (100,000 and continuous printing on A3 paper after 200,000 sheets have been copied) 10 copies are made and it is judged by the presence or absence of image unevenness in the halftone image.): No image unevenness occurs up to 200,000 sheets. Δ: No image unevenness occurs within 100,000 sheets. ×: Image unevenness occurs under 100,000 sheets. Occurrence

[0207]

[Table 2]

[0208]

[Table 3]

In any of the conditions shown in Table 2 and Table 3, the conductive foaming urethane cleaning roller is brought into contact with the photosensitive member and a bias voltage is applied to the cleaning roller to remove residual toner on the photosensitive member. When the charge is removed and the free length of the metal thin plate member and the cleaning blade is set to the condition of Expression 1, that is, 0.1 <b / a ≦ 0.9 and the vibration of the cleaning blade is stabilized, the blade is No curling, slipping of toner, and squeal of blade were observed, and good cleaning property was exhibited. No image unevenness was observed and a clear image was observed. On the other hand, 0.1 ≧ b /
In the case of a or b / a> 0.9, the vibration of the cleaning blade is not sufficiently stable, and under the conditions of (a) room temperature and normal humidity or more severe (b) high temperature and high humidity conditions, toner slipping, blade flipping or blade squeal Either of them occurred, and image unevenness also occurred.

Example 2 Below, the conditions of an example using the cleaning device according to claim 2 will be described.

Example 2 was carried out under the same conditions as in Example 1 except for the following conditions of the cleaning blade and the conditions of the photoconductor and the developer.

Conditional Structure of Cleaning Blade: As shown in FIG. 2, a thin metal plate member and a cleaning blade were attached to a supporting member. The thickness t ₁ of the cleaning blade and the thickness t ₂ of the thin metal plate member were changed as shown in Table 4.

Cleaning conditions in Table 4 Cleaning blade contact angle: 20 ° Cleaning blade load (N / m): 25 N / m Cleaning blade: Hokushin Kogyo KK (hardness 70
°, impact resilience 28%), free length a: 9 mm thin metal plate member: SUS303, free length b: 5.4 mm Conditions of photoconductor, developer Conditions of Table 4 Photoconductor: P2 Developer: 3 (toner: T3) The evaluation results are shown in Table 4.

[0214]

[Table 4]

The cleaning conditions shown in Table 4, that is, a cleaning roller made of conductive foam urethane is brought into contact with the photosensitive member, a bias voltage is applied to the cleaning roller, and the thickness ratio of the thin metal plate member to the cleaning blade is expressed by the formula 2,
That is, in the case of 1/200 ≦ t ₂ / t ₁ ≦ 1, the blade is not turned up and the toner does not slip through, and the blade does not squeal, which shows good cleaning property. Further, no image unevenness was generated. On the other hand 1/200> t ₂ / t ₁ or t ₂ / t _1>
In the case of 1, the toner slips through, the blade is turned over, or the blade is squealed, and image unevenness occurs.

[0216]

According to the present invention, namely, the cleaning action of the cleaning blade having the thin metal plate member and the conductive or semi-conductive cleaning roller is prevented from causing the blade to be turned up, and the cleaning means has a high performance for a long period of time. Is realized. As a result, the toner can be used for small particle diameter toner, and an image forming apparatus capable of forming a high quality image for a long period of time is realized.

Further, due to the effect of removing the residual toner by the conductive or semi-conductive cleaning roller, uniform cleaning performance which is not affected by the level of the potential existing on the photosensitive member can be obtained, and a high quality image can be formed. it can.

Further, since the vibration of the cleaning blade is absorbed and stabilized by the thin metal plate member, the peripheral speed ratio between the cleaning roller and the photosensitive member becomes unstable at the contact portion between the photosensitive member and the cleaning roller, and the photosensitive member is exposed from the cleaning roller. Retransfer of toner to the body is prevented, and cleaning failure due to these is prevented. As a result, the high image quality is maintained for a long period of time, and it becomes possible to form a high image quality image using the small particle size toner.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an overall configuration of an image forming apparatus of the present invention.

FIG. 2 is a configuration diagram of a cleaning device using the cleaning blade of the present invention.

FIG. 3A is an explanatory diagram showing projected images of toner particles having no corners, and FIGS. 3B and 3C are explanatory diagrams showing projected images of toner particles having corners.

FIG. 4 is a perspective view showing an example of a reactor equipped with a stirring blade that can be preferably used.

5 is a cross-sectional view of the reaction device shown in FIG.

FIG. 6 is a schematic view showing a specific example of the shape of a stirring blade.

[Explanation of symbols]

121 Photoreceptor 122 Charging Device 123 Developing Device 124 Transfer Device 125 Separator 126 Cleaning Device 126A Cleaning Blade 126B Metal Thin Plate Member 126C Cleaning Roller 126D Scraper 126F Supporting Member 126H Power Supply 127 PCL (Precharge Lamp) 130 Exposure Optical System a Cleaning Blade Free length b Free length of thin metal plate member t ₁ Thickness of cleaning blade t ₂ Thickness of thin metal plate member

Continued front page    F-term (reference) 2H005 EA05 EA07 EA10                 2H134 GA01 GB02 HA01 HA02 HA03                       HA04 HA05 HA11 HA13 HA17                       HD01 HD04 HD05 HD06 HD11                       HD19 KD07 KD08 KD13 KD16                       KE06 KF03 KG07 KG08 KH15

Claims (14)

[Claims] 1. An electrostatic latent image formed on a photoconductor is developed with a developer containing toner, and the toner image visualized by the development is transferred to a transfer material, and then remains on the photoconductor. In the cleaning device for removing the toner, the cleaning device includes a cleaning roller having a conductive or semi-conductive elastic body that comes into contact with the surface of the photoconductor, and a cleaning roller located downstream of the cleaning roller in the moving direction of the photoconductor. The cleaning blade is disposed, and the cleaning blade is held by the supporting member in close contact with the metal thin plate member on the surface opposite to the surface abutting on the photoconductor, and the free length a of the cleaning blade and the metal thin plate. A cleaning device, characterized in that the free length b of the member is designed to satisfy Equation 1. Formula 1 0.1 <b / a ≦ 0.9 2. An electrostatic latent image formed on a photoconductor is developed with a developer containing toner, and the toner image visualized by the development is transferred to a transfer material, and then remains on the photoconductor. In the cleaning device for removing the toner, the cleaning device includes a cleaning roller having a conductive or semi-conductive elastic body that comes into contact with the surface of the photoconductor, and a cleaning roller located downstream of the cleaning roller in the moving direction of the photoconductor. have arranged the cleaning blade and the cleaning blade is held by a supporting member in close contact with the sheet metal member in the surface opposite to the surface contacting the photosensitive member, the cleaning blade thickness t ₁ and the metal Thickness of thin plate member t ₂
Is designed to satisfy Equation 2. Formula 2 1/200 ≦ t ₂ / t ₁ ≦ 1 3. The cleaning device according to claim 1, wherein the cleaning roller is applied with a bias voltage having a polarity opposite to the charging polarity of the toner that contributed to toner image formation during the development. 4. The cleaning device according to claim 3, wherein a bias voltage is applied to the cleaning roller by a constant current power source. 5. The cleaning device according to claim 4, wherein the constant current power source outputs a constant current of 1 μA to 50 μA. 6. The cleaning roller has a resistance of 10 ² Ω.
The cleaning device according to any one of claims 1 to 5, having a surface resistivity of 10 ¹⁰ Ω. 7. The cleaning device according to claim 1, wherein the cleaning roller comprises a foam material and a resin film covering the foam material. 8. The cleaning blade is 0.1N
The cleaning device according to any one of claims 1 to 7, wherein the cleaning is performed by contacting the photoconductor in a counter method with a weight of / m to 30 N / m. 9. The cleaning blade is 0 ° to 4 °.
The cleaning is performed by contacting the photosensitive member by a counter method with a contact angle θ of 0 °.
8. The cleaning device according to any one of 8 above. 10. An electrostatic latent image formed on a photoconductor is developed with a developer containing toner, the toner image visualized by the development is transferred from the photoconductor to a transfer material, and then the photoconductor. An image forming method having a cleaning device for removing the residual toner, wherein the residual toner on the photoconductor is removed by using the cleaning device according to any one of claims 1 to 9. Forming method. 11. A toner having a variation coefficient of a shape factor of toner particles of 16% or less and a number variation coefficient of a number particle size distribution of the toner particles of 27% or less is used as the toner. The image forming method according to claim 10. 12. The toner has a shape factor of 1.2.
11. A toner containing 65% by number or more of toner particles in the range of 1.6 to 1.6 is used.
1. The image forming method described in 1. 13. The image forming method according to claim 10, wherein a toner containing 50% by number or more of toner particles having no corners is used as the toner. 14. An image forming apparatus using the image forming method according to claim 10.