JP2003005604A - Cleaning device, image forming method using cleaning device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning device with a superior cleaning function and also to provide an image forming method and an image forming apparatus using the cleaning method. SOLUTION: In the cleaning device, a cleaning roll provided with a conductive or a semiconductive elastic body brought into contact with a photoreceptor surface and a cleaning blade installed on the downstream side in the moving direction of the photoreceptor than the cleaning roll are provided. In this case, supporting members for the cleaning blade and the cleaning blade are joint by being overlapped in parallel in one part and an oscillation control material is adhered to the cleaning blade.

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, the toner produced by the granulation polymerization method, which is an effective method for producing a small particle size toner, has a small particle size and particles that are close to a spherical shape. In the cleaning process for cleaning the body, there is a strong tendency for toner to pass through between the photoconductor and the edge of the cleaning blade, so-called “sleeping”, resulting in poor cleaning.

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 a supporting member of the cleaning blade and a supporting member of the cleaning blade partially overlap each other in parallel and joined, and a damping material is attached to the cleaning blade.

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 a supporting member of the cleaning blade and a supporting member of the cleaning blade are partially overlapped in parallel and joined to each other, and a damping material is attached to the supporting member.

3. 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 comes into contact with the surface of the photoconductor, and the cleaning blade and a supporting member of the cleaning blade are partially overlapped in parallel with each other. Are joined together,
A cleaning device, characterized in that a damping material is attached between the cleaning blade and a supporting member.

4. As the damping material, the maximum loss coefficient η
The cleaning device according to any one of the items 1 to 3, wherein a viscoelastic material having a _max of 0.3 to 2.0 is used.

5. 5. The cleaning device according to any one of 1 to 4 above, 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.

6. 6. The cleaning device according to 5, wherein the bias voltage is applied to the cleaning roller by a constant current power supply.

7. 7. The cleaning device according to 6, wherein the constant current power source outputs a constant current of 1 μA to 50 μA.

8. The cleaning roller is 10 ² Ω
8. The cleaning device according to any one of 1 to 7 above, which has a surface resistivity of 10 to 10 ¹⁰ Ω.

9. 9. The cleaning device according to any one of 1 to 8 above, wherein the cleaning roller is made of an elastic body.

10. 10. The cleaning device according to any one of 1 to 9 above, wherein the cleaning roller is made of a foam material and a resin film covering the foam material.

11. The cleaning blade is 0.
11. The cleaning device according to any one of 1 to 10 above, wherein the cleaning device is brought into contact with the photoconductor in a counter method to perform cleaning with a weight of 1 N / m to 30 N / m.

12. The cleaning blade is 0 °
The cleaning method is carried out by contacting the photosensitive member by a counter method at a contact angle θ of -40 °.
The cleaning device according to any one of 1 to 11.

13. 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. In the image forming method for removing, the residual toner on the photoconductor is removed by using the cleaning device according to any one of 1 to 12 above.

14. 14. The toner according to the above 13, wherein the toner has a variation coefficient of shape coefficient of toner particles of 16% or less and a number variation coefficient of number particle size distribution of the toner particles of 27% or less. Image forming method.

15. The toner has a shape factor of 1.
13 or 1, wherein a toner containing 65 number% or more of toner particles in the range of 2 to 1.6 is used
4. The image forming method according to item 4.

16. 16. The image forming method described in any one of 13 to 15 above, wherein a toner containing 50% by number or more of toner particles having no corners is used as the toner.

17. An image forming apparatus using the image forming method described in any one of 13 to 16 above.

By adopting the above-mentioned constitution 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 turn-up and the toner can be prevented. 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, an automatic document feeding means for automatically feeding the document is provided, 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 by the speed v of the first mirror unit 115 composed of the illumination lamp and the first mirror constituting the scanning optical system, and V-shaped. 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 sensor 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 to form a visible toner image on the surface of the photoconductor 121. In the transfer paper transport unit D, transfer papers (transfer materials) P having different sizes are provided below the image forming unit.
Paper feed unit 14 as a transfer paper storage means for storing
1 (A), 141 (B), 141 (C) are provided, and a manual paper feeding unit 142 for laterally feeding paper manually is provided.
Is provided and the transfer sheet P selected from any one of them is fed by the guide roller 143 along the conveying path 140, and the registration roller pair 144 for correcting the inclination and deviation of the fed transfer sheet. The transfer sheet P is temporarily stopped and then re-fed, and is guided to the conveyance path 140, the pre-transfer roller 143a and the transfer entrance guide plate 146, and the toner image on the photoconductor 121 is transferred at the transfer position Bo. It is transferred to the transfer paper P by 124, and then the separator 1
The transfer sheet P is destaticized by 25, separated from the surface of the photoconductor 121, and conveyed to the fixing device 150 by the conveying device 145.

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.

The details of the cleaning device of the present invention will be described below for each constituent element. Cleaning Blade and Damping Material FIG. 2 is a block diagram of the cleaning device of the present invention.

In the cleaning device, a cleaning blade 126A is attached to a supporting member 126B.
A rubber elastic body is used as the material of the cleaning blade, and urethane rubber, silicon rubber, fluororubber, chloropyrene rubber, butadiene rubber, and the like are known as the material. Among these, urethane rubber is the other material. It is particularly preferable in that it has excellent wear characteristics as compared with rubber. For example, urethane rubbers obtained by reacting and curing the polycaprolactone ester and polyisocyanate described in JP-A-59-30574 are preferable.

On the other hand, the support member 126B is composed of a plate-shaped metal member or plastic member. As the metal member, a stainless steel plate, an aluminum plate, a vibration control steel plate, or the like is preferable.

The cleaning blade and the supporting member are characterized in that they are partially overlapped and joined in parallel with each other. Here, the term "superimposing and joining in parallel" means that the supporting member and the blade are superposed in parallel. Means joining. That is, as shown in FIGS. 3 (a) to 3 (f), it means that the support member and the blade are superposed in parallel with each other and joined at the parallel surface. On the other hand, joining in series means that
This means that the support member and the blade are linearly joined as shown in (g).

In the present invention, by joining the cleaning blade to the supporting member in parallel, a sufficient joining area between the cleaning blade and the supporting member can be ensured, stable joining is achieved, and vibration of the blade is stabilized. You can In addition, by attaching a damping material to the support member or cleaning blade, the vibration of the cleaning blade can be suppressed more effectively, and as a result, good cleaning without toner slipping or blade curling is achieved. it can.

The minimum width of the joint between the blade and the supporting member is 3 mm or more, preferably 5 mm or more in order to stabilize the joint strength. The blade and the support member can be joined by using an adhesive such as a thermoplastic resin adhesive, a thermosetting adhesive, an elastomer adhesive, or a double-sided adhesive tape, or a double-sided adhesive tape and an adhesive in combination.

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 of the characteristics of the cleaning blade, and even if the variation of the thickness of the cleaning blade is compared, the vibration control applied to the blade or its supporting member is suppressed. By effectively absorbing the vibration of the blade by the material, the setting condition of the cleaning blade on the surface of the photoconductor can be stably maintained within the proper region.

In the present invention, it is preferable that the tip of the cleaning blade which is brought into pressure contact with the surface of the photosensitive member is in pressure contact with the load in the direction opposite to the rotating direction of the photosensitive member (counter direction). As shown in FIG. 2, it is preferable that the tip portion of the cleaning blade forms a pressure-contact surface when pressure-contacting the photoconductor.

As shown in FIG. 2, 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 a vector value in the normal direction of the pressure contact force P'when the blade 126A is brought into contact with the photosensitive drum 121.

The contact angle θ represents the angle between the tangent line X at the contact point F of the photosensitive member and the blade before deformation (shown by the dotted line in the drawing). 126E is a rotary shaft that allows the support member to rotate, and 126G is a load spring.

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

As the physical properties of the cleaning blade, the hardness is 25 ± 5 ° C. and the JIS A hardness is 55-9.
A range of 0 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. Rebound is 8
If it exceeds 0, the blade is likely to be reversed, and if it is less than 25, the cleaning performance is deteriorated. Young's modulus is 29
The range of 4 to 588 N / cm ² is preferable.

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.

In the present invention, the vibration damping material is a member that is attached to the cleaning blade or its supporting member to suppress the vibration thereof, and may be any member as long as it has a vibration suppressing effect.

As a concrete damping material, as the vibration suppressing effect, the magnitude of the vibration is measured by the following method, and the magnitude of the vibration is attenuated by 20% or more as compared with the case without the damping material. Is preferred.

Method for measuring the magnitude of vibration A sensor of an acceleration detector NP-3210 manufactured by Ono Sokki Co., Ltd. was attached to a support member joined in parallel with a cleaning blade, and the vibration when the photoconductor rotates at a constant speed was measured by the sensor. Read for 10 seconds, and the output data from the sensor is arithmetically processed by "ONO SOKKI CF6400 4-channel intelligent FF analyzer" to obtain the average value of the amplitude of the vibration, which is determined by the vibration magnitude (nm) of the blade. expressed. However, if a damping material is attached to the sensor mounting position, remove the damping material at the sensor mounting position and measure.

As the damping material of the present invention, a viscoelastic material having both viscous and elastic properties is preferable. Particularly, the viscoelastic material preferably used in the present invention has a vibration frequency: 10
^When the vibration damping characteristics measured in the range (horizontal axis in Fig. 4) of ^-2 to 10 ⁷ Hz (with temperature (range of 0 to 100 ° C) as a parameter) are displayed in complex numbers, the dynamics represented by the real part are displayed. Ratio of shear modulus G ¹ and dynamic loss coefficient G ² of imaginary part G ² /
If G ¹ is η, the maximum value of η (η _max : maximum loss coefficient)
Is preferably 0.3 to 2.0, more preferably 0.5 to 1.5. A viscoelastic material with η _max in this range has a large earthquake-proof effect. Further, G ¹ when η _max is obtained is 6.9 × 10 ^{2 to} 6.9 × 10 ⁴ (kPa)
Is preferred.

The vibration damping characteristic is measured by a high frequency viscoelasticity spectrometer VES-HC (manufactured by Iwamoto Seisakusho), and η _max can be obtained from a graph showing the frequency dependence of η as shown in FIG. .

Commercially available vibration-damping materials for these are VEM series manufactured by Sumitomo 3M and LR manufactured by Bridgestone.
There are damping materials such as dampers in the series, but in addition to this, by compounding the damping material, it is possible to manufacture damping materials with different characteristics of G ¹ and η _max .

On the other hand, the present invention can effectively reduce the vibration of the cleaning blade and its supporting member by attaching these damping materials to the cleaning blade or the supporting member supporting the blade. Also, it has good toner cleaning properties and prevents blades from turning over.

FIG. 3 shows a concrete example of effective attachment of damping materials.
Shown in. In FIG. 3, the damping material is indicated by y (hatched portion), the cleaning blade is indicated by 126A, and the supporting member is indicated by 126B.

FIGS. 3A to 3E are examples of the present invention.
3 (f) and 3 (g) are examples other than the present invention.

In FIGS. 3A to 3E, the cleaning blade 126A and the supporting member 126B are partially overlapped in parallel and joined together. On the other hand, FIG. 3 (f) does not use a damping material, and FIG. 3 (g) has a cleaning blade 126A and a support member 126B joined in series.

FIG. 3A shows an example in which the damping material y is attached between the cleaning blade and the supporting member, FIG. 3B shows an example in which it is attached on the cleaning blade, and FIGS.
(E) is an example in which it is attached to a support member. By using the damping material in this manner, as shown in the results of the later examples, FIG. 3 (f) without the damping material or the cleaning blade 126A and the supporting member 126B joined in series. As compared with (g), FIGS. 3 (a) to 3 (e) show good cleaning characteristics in which the toner does not slip through and the blade is not turned over.

The pasting area (S ₁ ) of the above damping material is
When the area of the cleaning blade (the product of the length b of the length a and the photoreceptor axis of the free-length direction of the cleaning blade of FIG. 5) and S _2, S ₁ / S ₂ is in the range of 0.05 to 12 preferable. If it is less than 0.05, the effect is hard to come out, and if it exceeds 12, the effect is hard to increase. S ₁ / S ₂ is more preferably in the range of 0.3 to 5, most preferably in the range of 0.5 to 3.

The case where S ₁ <S _{2 is} the case where the bonded area of the damping material is smaller than the area of the cleaning blade. For example, the damping material bonding as shown in FIGS. It is one that In this case, it is particularly preferable to use FIGS.

The case where S ₁ = S _{2 is} the case where the bonding area of the vibration damping material and the area of the cleaning blade are equal, and any of FIGS. 3 (a) to 3 (d) may be used. In particular, FIG.
(B) is preferred.

The case of S ₁ > S ₂ means, for example, the case shown in FIG. 3 (e) or the case where the vibration damping material is attached to the entire cleaning device such that the area is larger than the area of the cleaning blade. Show.

The damping material can be attached to the cleaning blade or the supporting member by using a double-sided adhesive tape, an adhesive or the like, but the damping material itself is processed into a tape shape or a sheet shape, and as it is. What can be glued is
It can be used as it is.

Cleaning Roller As shown in FIG. 2, the cleaning roller 126C includes:
A bias voltage is applied by the constant current power source 126H to electrostatically remove the toner on the photoconductor 1 from the cleaning roller 126.
Aspirate to C. The polarity of the bias voltage contributes to the development in the developing means 4 and is opposite to the polarity of the toner forming the toner image. As shown in FIG.
As shown in FIG. 7, the scraper 126D as a removing unit contacts in a counter method to remove the toner collected from the photoconductor 1 and adhering to the cleaning roller 126C.

As the cleaning roller 126C, a conductive or semi-conductive and elastic cleaning roller is desirable.

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. The surface resistance is controlled by dispersing a conductive material such as carbon black, graphite, metal powder or metal oxide powder in these rubber layer, foam layer and resin layer.

Surface resistivity of the 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 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 is preferably rotated so that its abutting portion moves in the same direction as the surface of the photosensitive member. When the abutting portion moves in the opposite direction, when excess toner is present on the surface of the photoconductor, 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 to the bias voltage cleaning roller 126C by a power source 126H. The bias voltage electrostatically removes the toner adhering to the photoconductor 1 from the cleaning roller 1
It is a voltage to be sucked and removed by 26C, and 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 1,
Although the electric potential on the photoconductor 1 is not uniform, the toner is electrostatically removed from the cleaning roller 126 by applying a bias voltage from the constant current power source to the cleaning roller 126C.
When attracted to C, a substantially constant electric field that is not affected by the potential on the photoconductor 1 is formed between the surface of the photoconductor 1 and the surface of the cleaning roller 126C, and a uniform cleaning effect is obtained, and excellent cleaning is performed. It is effective. 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 1 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 means 4 by the recycling means 9 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 strongly attached to the cleaning roller 126C, and therefore it is preferable to collect the toner with a plurality of scrapers.

Next, the 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 photoreceptor used in the present invention is 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 having aluminum, tin oxide, indium oxide or the like deposited thereon, 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 electroconductive support used in the present invention may have a surface on which a sealed 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 draw layer) can also be provided. Examples of the material of the intermediate layer include a polyamide resin, a vinyl chloride resin, a vinyl acetate resin, and a copolymer resin containing two or more of repeating units of these resins. Among these undercoat resins, a polyamide resin is preferable as a resin that can reduce the increase in residual potential due to repeated use. The thickness of the intermediate layer using these resins is 0.01 to 0.5 μm.
Is preferred.

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

Photosensitive Layer The photosensitive layer structure of the photoconductor of the present invention may be a photosensitive layer structure 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.

As the solvent or dispersion medium used for forming the intermediate layer, photosensitive layer, protective layer and the like of the present invention, 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.
The coating process on the upper layer side of the photosensitive layer does not dissolve the lower layer film as much as possible, and in order to achieve uniform coating process, spray coating or circular amount control type (a circular slide hopper type is a typical example) Is preferably used. 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 65% by number or more of toner particles having a shape factor of 1.2 to 1.6 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.

The vibration stability of the cleaning blade also depends on the particle size of the toner particles. The smaller the particle size, the higher the adhesion force to the image carrier, so the vibration tends to be excessive, and the toner is 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 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 number% or more and controlling the number variation coefficient in the number particle size distribution to 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 that when a projected image of a toner particle on a plane is sandwiched by two parallel lines, the parallel line 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 obtained by taking a photograph of the toner particles magnified 2000 times with a scanning electron microscope, and then, based on the photograph, "SCANNING" is used.
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 slips 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 by 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 step 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 number variation coefficient of the toner are measured with a 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 for keeping 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 a projection where electric charges are concentrated or a projection that is easily worn by stress, that is, as shown in FIG. 6A. 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. 6B and 6C show projected images of toner particles having corners, respectively.

The toner having no corners 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 number% or more, preferably 70 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 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 polymerized 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. 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.

When the number average particle diameter is 3 to 8 μm, it is possible to reduce the presence of toner having excessive adhesion to the developer conveying member or toner having low adhesion 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) in a plurality of classes (0 to 0) at intervals of 0.23.
0.23: 0.23 to 0.46: 0.46 to 0.69:
0.69 to 0.92: 0.92 to 1.15: 1.15
1.38: 1.38 to 1.61: 1.61 to 1.84:
1.84-2.07: 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 manufacturing 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 as used 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 of producing the toner of the present invention, a method of preparing resin particles by associating or fusing them 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.

The polymerizable monomer used for the resin is styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-chlorostyrene, 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.

The resin excellent in the present invention preferably has a glass transition point of 20 to 90 ° C. and a softening point of 8
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 those selected from metal salts are 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 higher. 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 amount of the aggregating agent added may be a critical coagulation concentration or higher, but is preferably 1.2 times the critical coagulation concentration or higher.
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 based on the polymer-containing dispersion liquid to which the flocculant 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 also 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.

As the colorant used in the toner of the present invention, carbon black, magnetic materials, dyes, pigments and the like can be optionally used. Examples of the 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 at the step of polymerizing a 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, the charge control agents are various known ones,
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 constituent 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.
7 and 8 are a perspective view and a cross-sectional view showing an example of a polymerized toner reaction device, respectively. In the reactor shown in FIG. 7 and FIG. 8, 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.

7 and 8, 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 notch, 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. Stirrer blade 5 shown in FIG. 9 (a)
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 at least a gap 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 a polymerized toner in which resin particles are associated or fused with each other in an aqueous medium, the flow and temperature distribution of the medium in the reaction vessel at the fusion stage are controlled to further improve the shape after fusion. By controlling the heating temperature, 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 the polymerization toner in which the 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 the stirring blade is not particularly limited as long as it forms a laminar flow and does not form a turbulent flow. However, a continuous surface such as a rectangular plate shown in FIG. 9A is used. 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. 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 the 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.

In the case of using 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, magnetic particles of about 0.1 to 5 μm are contained in toner particles. 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.

Also, 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.

The two-component developer is prepared by mixing the toner and the carrier. 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.

[0185]

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

Preparation of Photoreceptor 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 was mixed and dispersed for 10 hours using a sand mill, and the charge generation layer was mixed. A coating liquid 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: 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 transporting 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.

[0192]

[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 and 4.0 L of ion-exchanged water
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-liter 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.

Heating was started, and when the liquid temperature reached 75 ° C., the entire amount of “initiator solution C” was added dropwise. Then, while controlling the liquid temperature to 75 ° C ± 1 ° C, 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 is referred to 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 a 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 the 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 temperature sensor, cooling pipe, nitrogen introducing device, 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 (salting out / fusing step). 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 (shape control step). 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. Then, it was washed with ion-exchanged water.

The non-spherical particles were dried at a suction temperature of 60 ° C. using a flash jet 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 salting out / fusion step and the shape control step, by controlling the number of revolutions of the stirring blade and the heating time of the liquid temperature, the variation coefficient of the shape and the shape coefficient is controlled, and further by the in-liquid classification, The toner T1 and the toner T2 shown in Table 1 were obtained by adjusting the variation coefficient of the particle size and the particle size distribution.

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, and controlling the liquid temperature, the number of revolutions of the stirring blade, and the heating time of the liquid temperature, the variation coefficient of the shape and the shape coefficient is controlled,
Further, the variation coefficient of the particle size and the particle size distribution was adjusted by in-liquid classification to obtain a toner T3 shown in Table 1 below.

[0210]

[Table 1]

Preparation of Developer 1 0.4 parts of hydrophobic silica particles having an average particle diameter of 12 nm (R805: manufactured by Nippon Aerosil Co., Ltd.) as external additives and 100 parts of toner T1 described above, and titania particles (T805: Nippon Aerosil Co., Ltd.) (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%.

[0212] A developer 1 having a toner concentration of 5% was prepared by mixing the above toner with a ferrite carrier having a volume average particle diameter of 60 µm and coated with a silicone resin.

Preparation of Developers 2 and 3 Developer 2 was prepared in the same manner except that the toner T2 was used instead of the toner T1 in the preparation of the developer 1.
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, image formation was carried out using an image forming apparatus having processing means for charging, exposing, developing, transferring, fixing and cleaning as shown in FIGS.

As the present photoreceptor, the negatively chargeable OP is used.
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 examples will be described below. Conditions of cleaning blade A combination (1A to 1G) of the joining form of the cleaning blade and the supporting member, the bonding position of the damping material, the contact load of the blade, and the contact angle (1A to 1G) was prepared as shown in Table 2.
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.

[0217] The cleaning blade: 70 ° Hardness, rebound resilience of 60%, a thickness of 2 mm, a free length 9 mm, photoreceptor axial length 340 mm, width 18mm, S ^_2: 6120mm ₂ Damping material: Scotch dump SJ2015X-Type11
0 (Sumitomo 3M) (maximum loss coefficient η _max ≈1.2) Bonding width of cleaning blade and support (parallel bonding: 9
mm, series connection 2 mm) Other cleaning conditions Cleaning blade contact angle: cleaning blade load (N / m) shown in Table 2: cleaning roller shown in Table 2 made of conductive urethane foam, surface resistivity 10 ³ Ω, hardness A cleaning roller composed of a 30 ° elastic roller, which was formed by winding urethane (thickness: 25 mm) on a metal shaft having a diameter of 6 mm to have a diameter of 16 mm (thickness: 25 mm), was brought into contact with the photosensitive member so that the contact width was 2 mm.

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 for Photoreceptor and Developer Photoreceptor: P1 Developer: 1 (toner T1) Under the above conditions and the following environmental conditions, 200,000 sheets of 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 Table 2.

Evaluation Items and Evaluation Criteria Blade flipping ○: No blade flipping up to 200,000 sheets △: Blade flipping does not occur up to 100,000 sheets ×: Blade flipping occurs at less than 100,000 sheets (100,000 and 200,000 sheets) After copying is completed, 10 copies are continuously made on A3 paper, and it is judged by the presence or absence of toner slippage in solid white area.): Up to 200,000 sheets No filming due to toner slippage. △: Up to 100,000 sheets due to toner slippage. No occurrence of jamming x: Filming occurs due to toner slippage when the number of sheets is less than 100,000 The magnitude of vibration of the cleaning blade A sensor of an acceleration detector NP-3210 manufactured by Ono Sokki Co., Ltd. is attached to a supporting member joined in parallel with the cleaning blade, The vibration when the photoconductor rotates at a constant speed is read by the sensor for 10 seconds, Obtain an average value of the amplitude of the vibration of the output data from the server and processing in "ONO SOKKI CF6400 4-channel intelligent FF Analyzer", it expressed this magnitude of vibration of said blade ([mu] m).

The evaluation results are shown in Table 2.

[0224]

[Table 2]

As is clear from Table 2, the cleaning roller made of conductive urethane foam is brought into contact with the photosensitive member and a bias voltage is applied to the cleaning roller, whereby the charge of the residual toner on the photosensitive member is removed, and Whereas the cleaning blade and the supporting member are joined in parallel and the vibration damping materials are adhered to the examples of the present invention 1A to 1E, the toner does not slip through the blade and the blade is not turned over, and shows good cleaning characteristics. , 1F, 1G outside the present invention
Also in the evaluation of the magnitude of vibration, the vibration was larger than that in the present invention, and toner slip-through, blade curling, and the like occurred.

Example 2 The following cleaning blade conditions and photoconductor,
The evaluation was performed under the same conditions as in Example 1 except for the developer conditions.

Conditions of Cleaning Blade The conditions of the cleaning blade and the damping material were changed to the following.

Cleaning blade: hardness 70 degrees, impact resilience 50%, thickness 2.5 mm, free length 5 mm Vibration damping material: Scotch dump SJ2015X-Type11
2 (manufactured by Sumitomo 3M) (maximum loss coefficient η _max ≈1.0) Other cleaning conditions Cleaning blade contact angle: Table 3 Cleaning blade load (N / m): Table 3 Photoreceptor, developer Conditions Photoconductor: P2 Developer: 2 (toner: T2) Other evaluation conditions are the same as in Example 1.

The results are shown in Table 3.

[0230]

[Table 3]

As is clear from Table 3, the cleaning roller made of conductive urethane foam is brought into contact with the photosensitive member and a bias voltage is applied to the cleaning roller, whereby the charge of the residual toner on the photosensitive member is removed, and While the cleaning blade and the supporting member are joined in parallel, and the examples of the present invention 2A to 2E in which the vibration damping material is attached, the toner does not slip through and the blade is not turned up, and the good cleaning property is shown. , 2F, 2G outside the present invention
Also in the evaluation of the magnitude of vibration, the vibration was larger than that in the present invention, and toner slip-through, blade curling, and the like occurred.

Example 3 The following cleaning blade conditions and photosensitive member,
Example 3 was carried out under the same conditions as in Example 1 except for the developer conditions.

Cleaning blade conditions The type of damping material was changed as shown in Table 4.

Conditions for photoconductor and developer Photoconductor: P2 Developer: 2 (toner: T2) The evaluation results are shown in Table 4.

[0235]

[Table 4]

As is clear from Table 4, the conductive urethane foam cleaning roller is brought into contact with the photosensitive member and a bias voltage is applied to the cleaning roller, whereby the charge of the residual toner on the photosensitive member is removed, and The examples of the present invention 3A to 3C in which the cleaning blade and the supporting member are joined in parallel and the vibration damping material is adhered thereto do not cause the toner to slip through or the blade is turned over, and show good cleaning characteristics.

Example 4 Example 4 was carried out under the same conditions as in 1A of Example 1 except for the following cleaning blade conditions.

Condition of Cleaning Blade The viscoelastic properties (η _max and G ¹ ) of the vibration damping material were changed as shown in Table 5. The evaluation results are shown in Table 5.

[0239]

[Table 5]

As is apparent from Table 5, the cleaning roller made of conductive urethane foam is brought into contact with the photosensitive member and a bias voltage is applied to the cleaning roller to remove the electric charge of the residual toner on the photosensitive member, and If the maximum loss coefficient η _max of the vibration control material is in the range of 0.3 to 2.0, the toner slip-through and blade curling are suppressed, and good cleaning characteristics are exhibited, and the vibration magnitude The damping effect is also large. Especially, the damping material having the maximum loss coefficient η _max in the range of 0.5 to 1.5 has a great effect.

Example 5 Example 5 was carried out under the same conditions as in Example 1 except for the following cleaning blade conditions.

Condition of Cleaning Blade As shown in Table 6, the bonding area S _{1 of the} vibration damping material and the cleaning blade area S ₂ were further changed. The evaluation results are shown in Table 6.

[0243]

[Table 6]

As is clear from Table 6, the cleaning roller made of conductive urethane foam is brought into contact with the photosensitive member and a bias voltage is applied to the cleaning roller, whereby the electric charge of the residual toner on the photosensitive member is removed, and S ₁ / S ₂
The effect is seen in all the regions where the ratio is 0.05 to 12, but the effect is particularly large in the region of 0.3 to 12.

[0245]

According to the present invention, the cleaning action of the cleaning blade having the vibration damping material and the conductive or semi-conductive cleaning roller prevents the toner from slipping through and the blade from being turned over, and the performance is improved for a long period of time. The cleaning performance of 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 can be obtained without being influenced by the level of the potential existing on the photosensitive member, and a high quality image can be formed. it can.

Further, the vibration of the cleaning blade is absorbed and stabilized by the vibration control material, so that the peripheral speed ratio between the cleaning roller and the photoconductor becomes unstable at the contact portion, and the toner retransfers from the cleaning roller to the photoconductor. Etc. are prevented, and defective cleaning 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. 3 is a diagram showing a specific example of effective attachment of vibration damping materials.

FIG. 4 is a graph showing the frequency dependence of η.

FIG. 5 is a diagram showing an area of a cleaning blade.

FIG. 6A is an explanatory diagram showing a projected image of toner particles without corners, and FIGS. 6B and 6C are explanatory diagrams showing projected images of toner particles with corners.

FIG. 7 is a perspective view showing an example of a polymerized toner reaction device.

FIG. 8 is a cross-sectional view showing an example of a polymerized toner reaction device.

FIG. 9 is a schematic view showing a specific example of the shape of a stirring blade.

[Explanation of symbols]

121 photoconductor 122 Charger 123 Developing device 124 Transfer device 125 separator 126 Cleaning device 126A cleaning blade 126B support member 127 PCL (pre-charge lamp) 130 Exposure optical system Free length of L cleaning blade t Cleaning blade thickness

Continued front page    F-term (reference) 2H005 AA15                 2H134 GA01 GB02 HA01 HA03 HA04                       HA05 HA09 HA11 HA13 HA16                       HA17 HD01 HD05 HD06 HD11                       HD19 HD20 KB02 KB06 KB09                       KD06 KD07 KD08 KD12 KE07                       KE09 KF03 KG07 KH01 KH05                       KH15

Claims (17)

[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. Having a cleaning blade arranged, and the cleaning blade and a supporting member of the cleaning blade,
A cleaning device characterized in that a part of each of them is superposed and joined in parallel, and a damping material is attached to the cleaning blade. 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. Having a cleaning blade arranged, and the cleaning blade and a supporting member of the cleaning blade,
A cleaning device, characterized in that a part of each of them is superposed and joined in parallel, and a damping material is attached to the support member. 3. 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 removed toner, the cleaning device has a cleaning roller having a conductive or semi-conductive elastic body that comes into contact with the surface of the photoconductor, and the cleaning blade and a supporting member of the cleaning blade are part of each other. The cleaning device is characterized in that a vibration damping material is bonded between the cleaning blade and the support member. 4. The maximum loss coefficient η _max as the damping material.
The viscoelastic material of 0.3 to 2.0 is used, The cleaning device of any one of Claims 1-3 characterized by the above-mentioned. 5. The cleaning roller according to any one of claims 1 to 4, wherein a bias voltage having a polarity opposite to a charging polarity of the toner that contributes to toner image formation is applied to the cleaning roller. Cleaning device. 6. The cleaning device according to claim 5, wherein a bias voltage is applied to the cleaning roller by a constant current power supply. 7. The cleaning device according to claim 6, wherein the constant current power source outputs a constant current of 1 μA to 50 μA. 8. The cleaning roller has a resistance of 10 ² Ω.
The cleaning device according to claim 1, which has a surface resistivity of 10 ¹⁰ Ω. 9. The cleaning device according to claim 1, wherein the cleaning roller is made of an elastic material. 10. The cleaning device according to claim 1, wherein the cleaning roller is made of a foam material and a resin film that covers the foam material. 11. The cleaning blade is 0.1
The cleaning device according to claim 1, wherein cleaning is performed by contacting the photoconductor in a counter method with a weight of N / m to 30 N / m. 12. The cleaning blade is 0 ° to
2. The cleaning is performed by contacting the photoconductor by a counter method at a contact angle θ of 40 °.
The cleaning device according to any one of 1 to 11. 13. 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. In the image forming method for removing the above residual toner,
The residual toner on the photoconductor is defined as any one of claims 1 to 12.
An image forming method, characterized in that the image is removed by using the cleaning device described in the item. 14. A toner having a variation coefficient of the shape factor of toner particles of 16% or less and a variation coefficient of the number particle size distribution of the toner particles of 27% or less is used as the toner. The image forming method according to claim 13. 15. The toner has a shape factor of 1.2.
14. A toner containing 65% by number or more of toner particles in the range of from 1.6 to 1.6 is used.
4. The image forming method according to item 4. 16. The image forming method according to claim 13, wherein a toner containing 50% by number or more of toner particles having no corners is used as the toner. 17. An image forming apparatus using the image forming method according to any one of claims 13 to 16.