JP2008276005A - Image forming apparatus and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of providing a stable image which is free from defective image quality such as toner stripe stain and irregularity on a highlight part irrespective of image history and environment, over a long term by improving the ability of cleaning transfer remaining toner on an image retainer after transfer and, and to provide a process cartridge. <P>SOLUTION: The image forming apparatus has a cleaning means provided with a cleaning blade and a stagnation control member which holds the scraped transfer remaining toner, and the image forming apparatus uses a developer including such a toner that a fundamental fluid energy amount A measured by a powder rheometer at air flow rate 0 ml/min is 150 to 600 mJ, and the value obtained by dividing fluidizing energy B by the fundamental fluid energy amount A is 0.3 to 0.9, the fluidizing energy B being measured by the powder rheometer at air flow rate 0 ml/min after performing deaeration of the toner by fluidizing the toner at air flow rate 80 ml/min. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus and a process cartridge.

A method of visualizing image information through an electrostatic latent image such as electrophotography is currently used in various fields. In electrophotography, an electrostatic latent image formed on a photoreceptor by a charging and exposure process is developed with a developer containing toner, and visualized through a transfer and fixing process.
As such an image forming apparatus, conventionally, a blade cleaning system is used to remove the transfer residual toner on the photoreceptor.

The following proposals have been made for the blade cleaning system.
There has been proposed a system in which the toner reservoir formed at the contact portion of the cleaning blade with the photosensitive member is set to 1 mm or less and the rubber hardness of the blade is set to 70 or more (see, for example, Patent Documents 1 and 2).
A blade cleaning system has been proposed in which a toner is temporarily accumulated in a nip portion and a cleaning blade is provided to press the toner (see, for example, Patent Document 3).

There has been proposed a blade cleaning system in which a blade installed downward, a lower seal for storing toner at a position facing the blade, and a toner dampening member are installed (see, for example, Patent Document 4).
There has been proposed a blade cleaning system that forms an untransferred toner image on a transfer paper transport belt provided with a cleaner, supplies toner to a cleaner, and forms a toner reservoir in a blade nip (for example, (See Patent Document 5).

There has been proposed a cleaning blade having a member for temporarily stopping toner on the back surface and a blade cleaning system in which a magnetic brush is installed upstream thereof (see, for example, Patent Documents 6 and 7).
A blade cleaning system has been proposed in which a cleaning blade having a toner temporary stopper member for forming a toner reservoir at the tip is reciprocated in the direction of the rotation axis of the photosensitive member (see, for example, Patent Document 8).

There has been proposed a blade cleaning system in which a toner temporary dampening member having a wiper blade structure is installed upstream of a cleaner (see, for example, Patent Document 9).
A blade cleaning system has been proposed in which a part of the toner after cleaning removal is supplied again to the intermediate transfer body cleaner (see, for example, Patent Document 10).

A blade cleaning system having a spherical toner containing a cleaning aid, an image carrier having a tensile elastic modulus of 0.5 to 1.5 Gpa, and a cleaning blade has been proposed (see, for example, Patent Document 11).
JP 61-241777 A JP-A 61-239278 JP 2000-147968 A JP 11-161125 A JP-A-9-258627 JP 2005-258044 A JP 2006-10955 A JP 2006-10957 A JP 2006-227583 A JP 2005-43504 A JP 2003-140468 A

  The present invention improves the ability to clean the transfer residual toner on the image carrier after transfer, and image quality defects such as toner streaks and highlight unevenness do not occur over a long period of time regardless of the image history or environment. An object of the present invention is to provide an image forming apparatus and a process cartridge capable of obtaining a stable image.

The above problems are solved by the present invention described below.
That is, the present invention
<1> The electrostatic latent image is formed by an image carrier, a charging unit that charges the image carrier, a latent image forming unit that forms an electrostatic latent image on the surface of the charged image carrier, and a developer containing toner. Developing means for developing and forming a toner image on the image carrier, transfer means for transferring the toner image onto a recording medium to form an unfixed transfer image, and the unfixed image transferred on the recording medium A fixing means for fixing the transferred image of the toner, and a cleaning means for cleaning the transfer residual toner on the image holding body, wherein the cleaning means is fixed at one end to a support made of a rigid body, and at the other end, A cleaning blade made of an elastic body having a scraping portion that contacts the image holding member and scrapes off transfer residual toner on the image holding member, and attached to the back side of the cleaning blade, and scraped by the scraping portion. Before taken A retention control member that blocks toner remaining after transfer and forms a toner reservoir. The toner has an air flow rate of 0 ml / min, a tip speed of the rotor blade of 100 mm / sec, and an entrance angle of the rotor blade of -5 °. The basic fluidity energy amount A when measured with a powder rheometer under the above conditions is 150 mJ or more and 600 mJ or less, the aeration flow rate is 80 ml / min, the tip speed of the rotor blade is 100 mm / sec, and the approach angle of the rotor blade is -5 °. After giving a history of deaeration by fluidizing under conditions, fluidization energy B when measured under conditions of aeration flow rate 0 ml / min, tip speed of rotor blade 100 mm / sec, angle of approach of rotor blade -5 °, The basic fluidity energy amount A is a relationship in which (fluidization energy B / basic fluidity energy amount A) is 0.3 or more and 0.9 or less. An image forming apparatus, characterized by.

<2> the cleaning blade and the cross-sectional area of the retention control member, surrounded by, and the image carrier surface region, the image according to, characterized in that at 0.5 mm ² or more 5 mm ² or less <1> Forming device.
<3> The length of the stay control member from the same height as the tip of the cleaning blade to the tip of the stay control member is 0.5 mm or more and 5 mm or less. <1> or <2 The electrophotographic image forming apparatus according to <1>.

<4> The cleaning blade has a length from the same height as the upper end of the support made of the rigid body to the upper end of the cleaning blade of 3 mm or more and 15 mm or less. <1> to <3 The electrophotographic image forming apparatus according to any one of the above.

<5> The electrophotographic image forming apparatus according to any one of <1> to <4>, wherein the developer includes a carrier.
<6> The electrophotographic image forming apparatus according to <5>, wherein the carrier has an average circularity of 0.98 or more and 1.00 or less and a residual magnetization of 2 emu / g or more and 10 emu / g. It is.

<7> The electrostatic latent image formed on the image carrier can be developed with at least an image carrier and a developer containing toner, and the toner image can be held by the image carrier. A developing means formed on the body, and a cleaning means for cleaning the transfer residual toner on the image holding body after transfer, wherein the cleaning means is fixed to a support made of a rigid body, and the other end A cleaning blade made of an elastic body having a scraping portion that contacts the image holding member and scrapes off transfer residual toner on the image holding member; and the scraping portion attached to the back side of the cleaning blade. And a retention control member that forms a toner reservoir by blocking the transfer residual toner scraped off by the toner, and the toner has an aeration flow rate of 0 ml / min and a tip speed of the rotor blade of 100 m. / Sec, the basic flow energy amount A when measured with a powder rheometer under the condition of the approach angle of the rotor blade of −5 ° is 150 mJ or more and 600 mJ or less, the air flow rate is 80 ml / min, the tip speed of the rotor blade is 100 mm / After giving a history of degassing by fluidizing under the condition of sec, rotor blade approach angle -5 °, conditions of air flow rate 0 ml / min, tip speed of rotor blade 100 mm / sec, rotor blade approach angle -5 ° The fluidization energy B and the basic fluidity energy amount A when measured in (3) have the relationship that (fluidization energy B / basic fluidity energy amount A) is 0.3 or more and 0.9 or less. This is a featured process cartridge.

<8> the cleaning blade, and the retention control member, the cross-sectional area of the region enclosed by the surface of an image holding member, the process according to, characterized in that at 0.5 mm ² or more 5 mm ² or less <7> It is a cartridge.
<9> The length of the stay control member from the same height as the upper end of the cleaning blade to the tip of the stay control member is 0.5 mm or more and 5 mm or less. <7> or <8 > Is a process cartridge.

<10> The length of the cleaning blade from the same height as the tip of the support made of the rigid body to the tip of the cleaning blade is 3 mm or more and 15 mm or less. <7> to <9 The process cartridge according to any one of the above.

<11> The process cartridge according to any one of <7> to <10>, wherein the developer includes a carrier.
<12> The process cartridge according to <11>, wherein the carrier has an average circularity of 0.98 or more and 1.00 or less and a residual magnetization of 2 emu / g or more and 10 emu / g.

  According to the present invention, the ability to clean the transfer residual toner on the image holding member after transfer is improved, and image quality defects such as toner streak stains and uneven highlights are not generated regardless of the image history and environment. It is possible to provide an image forming apparatus and a process cartridge capable of obtaining the obtained image over a long period of time.

Hereinafter, the present invention will be described in detail.
<Image forming apparatus>
The image forming apparatus according to the present invention includes an image carrier, a charging unit that charges the image carrier, a latent image forming unit that forms an electrostatic latent image on the surface of the charged image carrier, and a developer containing toner. Developing means for developing an electrostatic latent image and forming a toner image on the image carrier, transfer means for transferring the toner image onto a recording medium to form an unfixed transfer image, and transferring the toner image onto the recording medium A fixing means for fixing the unfixed transferred image, and a cleaning means for cleaning the transfer residual toner on the image holding member, wherein the cleaning means is fixed to a support made of a rigid body at one end. A cleaning blade made of an elastic body having a scraping portion that contacts the image holding member and scrapes the transfer residual toner on the image holding member at the other end, and is attached to the back side of the cleaning blade, Scraping And a retention control member that forms a toner reservoir by blocking the residual toner that has been scraped off in step 1. The toner has an aeration flow rate of 0 ml / min, a tip speed of the rotor blade of 100 mm / sec, The basic fluidity energy A when measured with a powder rheometer at an entry angle of -5 ° is 150 mJ or more and 600 mJ or less, the aeration flow rate is 80 ml / min, the tip speed of the rotor blade is 100 mm / sec, and the rotor blade enters. After giving a history of degassing by fluidizing at an angle of -5 °, flow when measured under the conditions of aeration flow rate of 0 ml / min, tip speed of the rotor blade of 100 mm / sec, and entrance angle of rotor blade of -5 ° The fluidization energy B and the basic fluidity energy amount A are (fluidization energy B / basic fluidity energy amount A) of 0.3 or more and 0.00. Characterized in that it has a become relationship below.

Conventionally, in order to improve the cleaning property, it has been proposed to form a toner reservoir at the contact portion between the photosensitive member (image holding member) and the cleaning blade.
If there is no toner accumulation, the cleaning blade is likely to be turned over, and streaks due to the toner slipping through the contact portion between the photosensitive member and the cleaning blade, or an abnormal increase in the driving torque of the photosensitive member. There are problems such as outages.
On the other hand, if there is a toner pool, this toner pool scrapes off the toner adhering to the photoconductor and lowers the adhesion force to the photoconductor. At the same time, the friction resistance of the cleaning blade is lowered and the cleaning blade is turned up. In order to suppress the occurrence, it is considered that the cleaning property is improved.

However, even if this toner pool is present, if images with low image density are output continuously, streaks due to toner slipping through the contact portion between the photoreceptor and the cleaning blade may occur, resulting in the quality of the output image. This is a cause of deterioration and member contamination in the image forming apparatus. It was found that the following phenomenon occurred.
That is, the same toner continues to stay for a long time at the portion where the edge of the blade, which is the deepest part of the toner pool, contacts the photoconductor, and continues to receive high mechanical pressure and shearing force. Additives are liberated or buried significantly. In addition, the toner is destroyed and fine powder is generated, or internal fixing auxiliary components are exposed. For this reason, if images with low image density are continuously output, the toner in the deepest part of the toner pool is reduced in fluidity and increased in adhesion.

  As a result, toner and toner component aggregates adhere to the edge of the cleaning blade, and the blade edge cannot be uniformly pressed against the photosensitive member, and toner slip occurs. That is, in order to stably obtain high cleaning performance for a long period of time without being influenced by the image density history, it is necessary to appropriately maintain the toner reservoir and replace the toner forming the toner reservoir.

(toner)
First, the toner used in the present invention will be described.
The toner used in the present invention (hereinafter sometimes simply referred to as “toner”) is measured by a powder rheometer under the conditions of an airflow rate of 0 ml / min, a tip speed of the rotor blade of 100 mm / sec, and an entrance angle of the rotor blade of −5 °. When the basic fluidity energy amount A is 150 mJ or more and 600 mJ or less, the air flow is 80 ml / min, the tip speed of the rotor blade is 100 mm / sec, and the inlet angle of the rotor blade is -5 °. After giving the history, the fluidization energy B measured under the conditions of the aeration flow rate 0 ml / min, the tip speed of the rotor blade 100 mm / sec, and the approach angle -5 ° of the rotor blade, and the basic fluid energy amount A are: (Fluidization energy B / basic fluidity energy amount A) has a relationship of 0.3 to 0.9.

  As a result of intensive studies by the inventors, in order to maintain the toner reservoir and to appropriately replace the toner that forms the toner reservoir, a retention control member that forms the toner reservoir is provided in the cleaning blade, and the toner It was found that the behavior during degassing was important. It has also been found that it is preferable that the cleaning blade vibrates minutely (minute behavior). The cleaning blade vibrates minutely when rubbing the photoconductor, and the microvibration gradually releases the distortion of the cleaning blade and suppresses turning, thereby maintaining a stable pressing state between the cleaning blade edge and the photoconductor. maintain.

On the other hand, the minute vibration of the cleaning blade affects the behavior of the toner staying in the toner reservoir. The toner exposed to the vibration environment is degassed by vibration or fluidized by embracing air. It has been found by the inventors that the behavior of the toner in the toner reservoir can be expressed by a deaeration test using the following powder rheometer.
Here, the deaeration test means that after the air is applied to the toner layer in the vessel and fluidized, the air in the toner layer is extracted with a stirring blade under a certain condition (deaeration work) and then applied to the stirring blade. By measuring the load, the ease of air release from the fluidized toner layer and the ease of movement of the toner layer as powder at that time are measured.

In the deaeration test, air flow is applied and then deaeration is performed. The toner adhering to the layer on the photoconductor is scraped (= fluidized), and minute vibration is given to the scraped toner reservoir (= deaeration). It is thought that the situation is reproduced.
If this deaeration property is too low, the toner tends to move and become unstable in the toner reservoir in the blade nip portion, and the toner tends to spill out or rise up. Toner that spills or rises from the toner reservoir may contaminate the inside of the image forming apparatus and cause a failure, or may directly contaminate the recording medium and appear as dirt on the output image.

  On the other hand, if the degassing property is too high, the toner easily moves down in the toner pool in the blade nip, and the same toner stays in the toner pool. It sticks to the edge of the blade, scrapes off the toner, and causes a reduction in scraping performance. If the scraping performance of the blade is reduced, untransferred toner and transfer residual toner on the photoreceptor may pass through the cleaning blade nip, contaminating the charger, mixing colors of the developing machine, and contaminating the output image. It causes image quality degradation.

  As in the present invention, the cleaning means includes the stay control member, and the minute vibration of the cleaning blade and the degassing property of the toner are in an appropriate region, so that the formation of the toner pool and the replacement of the toner are appropriately performed. . Further, the cleaning means includes an elastic body having a scraping portion that is fixed to a support body made of a rigid body at one end and scrapes off transfer residual toner on the image support body at the other end. Therefore, when the image carrier is driven, minute vibrations are efficiently generated at the tip of the cleaning blade, and curling can be suppressed and an appropriate toner retention state can be obtained.

The degassing property can be evaluated by obtaining the basic fluidity energy amount A and fluidization energy B as described later.
Here, the basic fluidity energy amount A and fluidization energy B will be described. These are amounts of fluidity energy obtained by fluidity measurement with a powder rheometer.

  When measuring the fluidity of particles, it is more influenced by many factors than when measuring the fluidity of liquids, solids, or gases. It is difficult to specify the exact fluidity of the particles. In addition, even if a factor to be measured (for example, particle size) is determined to specify fluidity, the factor actually has little effect on fluidity or only in combination with other factors. The significance of measuring the factor may arise, and even determining the measurement factor is difficult.

  Furthermore, the fluidity of the powder varies significantly depending on external environmental factors. For example, in the case of a liquid, even if the measurement environment changes, the fluctuation range of the fluidity is not so large, but the fluidity of the particles is greatly affected by external environmental factors such as humidity and the state of the flowing gas. fluctuate. It is not clear which measurement factors are affected by these external environmental factors, so even if measured under strict measurement conditions, the reproducibility of the measured values obtained is actually poor. is there.

  In addition, the flowability when the developer (toner) stays in the toner reservoir has been taken as an index of repose and bulk density, but these physical property values are indirect to the flowability of the developer. In addition, it is difficult to quantify and manage the fluidity of the developer collected on the vibrating blade in a dynamic environment.

  However, since the powder rheometer can measure the amount of fluid energy applied from the toner to the rotating blades of the measuring machine, the powder rheometer can be obtained as a sum of the factors attributable to fluidity. Therefore, in the powder rheometer, as in the past, for the toner obtained by adjusting the physical property value and particle size distribution of the surface, determine the items to be measured and find the optimum physical property value for each item and measure it. The flowability can be measured directly.

  As a result, it is possible to determine whether it is suitable as a toner used for developing an electrostatic image by confirming whether it falls within the above numerical range with a powder rheometer. Such toner production management is a method that is extremely suitable for practical use as compared to the conventional method of managing by indirect values with respect to keeping the toner fluidity constant. Moreover, it is easy to make measurement conditions constant, and the reproducibility of measured values is high.

  That is, the method for specifying the fluidity by the value obtained by the powder rheometer is simple, accurate and highly reliable as compared with the conventional method.

Next, a method for measuring fluidity using a powder rheometer will be described.
The powder rheometer is a fluidity measuring device that directly measures fluidity by simultaneously measuring rotational torque and vertical load obtained by rotating a rotating blade spirally in packed particles. By measuring both the rotational torque and the vertical load, the fluidity including the characteristics of the powder itself and the influence of the external environment can be detected with high sensitivity. In addition, since the measurement is performed with the particle filling state kept constant, data with good reproducibility can be obtained.

  Measurement is performed using FT4 manufactured by freeman technology as a powder rheometer. In addition, in order to eliminate the influence of temperature and humidity before the measurement, toner that has been left at a temperature of 22 ° C. and a humidity of 50% RH for 8 hours or more is used.

  First, a toner container is filled with an amount of toner exceeding a height of 89 mm in a split container having an inner diameter of 50 mm (a cylinder having a height of 51 mm placed on a 160 mL container having a height of 89 mm so that it can be separated vertically).

  After the toner is filled, the sample is homogenized by gently stirring the filled toner. This operation will be called conditioning in the following.

  During conditioning, the rotor blades are gently agitated in a rotating direction that does not receive any resistance from the toner so that the toner is not stressed in the filled state, removing most of the excess air and partial stress, and ensuring that the sample is homogeneous. Put it in a state. Specific conditioning conditions are agitation at a tip angle of 60 mm / sec with an approach angle of −5 °.

  At this time, the propeller-type rotor blades move downward simultaneously with the rotation, so that the tip draws a spiral, and the angle of the spiral path drawn by the propeller tip at this time is called the entry angle.

  After repeating the conditioning operation four times, the container upper end of the split container is gently moved, and the toner inside the vessel is scraped off at a height of 89 mm to obtain a toner filling the 160 mL container. The conditioning operation is performed because it is important to always obtain a powder having a constant volume in order to obtain the fluid energy amount stably.

  The toner thus obtained is transferred to a 200 mL container having an inner diameter of 50 mm and a height of 140 mm. After the toner was transferred to the 200 mL container, the above conditioning operation was further performed five times, and then the tip speed of the rotating blade was 100 mm while moving from the bottom of the container to a height of 110 mm to 10 mm at an entrance angle of -5 °. Measure the rotational torque and vertical load when rotating at / sec. The rotation direction of the propeller at this time is the reverse direction to the conditioning (clockwise as viewed from above), and this measurement is the “basic fluidity energy A” measurement.

The relationship between the rotational torque or the vertical load with respect to the height H from the bottom surface is shown in FIGS. FIG. 2 shows the energy gradient (mJ / mm) with respect to the height H obtained from the rotational torque and the vertical load. The area obtained by integrating the energy gradient in FIG. 2 (shaded area in FIG. 2) is the fluid energy amount (mJ). The flowable energy amount is obtained by integrating the section from 10 mm to 100 mm in height from the bottom.
Moreover, in order to reduce the influence by an error, let the average value obtained by performing this conditioning and energy measurement operation cycle 5 times be a fluid energy amount (mJ).

  The rotor blade has a diameter of 48 mm of a two-blade propeller type shown in FIG. 3 manufactured by freeman technology.

  After conditioning, when the rotational torque and vertical load of the rotor blade were measured, the “basic flow” was performed under the conditions of an aeration flow rate of 0 ml / min, a tip speed of the rotor blade of 100 mm / sec, and an entrance angle of the rotor blade of −5 °. The measured fluidity energy amount is “basic fluidity energy amount A” by the measurement of “energy energy A”.

In addition, after conditioning, air with an air flow rate of 80 ml / min was introduced from the bottom of the container, fluidized under the conditions of a tip speed of the rotor blade of 100 mm / sec and an entrance angle of the rotor blade of -5 °, and a history of deaeration was given. Thereafter, the fluidity energy amount measured under the conditions of the aeration flow rate of 0 ml / min, the tip speed of the rotor blades of 100 mm / sec, and the approach angle of the rotor blades of −5 ° is the “fluidization energy amount B”. Here, the history of deaeration refers to repeating the conditioning operation four times under the condition of the aeration flow rate of 0 ml / min. The toner layer fluidized by airflow and agitation is gradually conditioned by the conditioning operation. There are methods of degassing such as giving vibration and tapping, but the basic effects of degassing are all the same. In the present invention, a stable deaeration condition is obtained, and a history of deaeration is given by performing a conditioning operation using a powder rheometer which is excellent in reproducibility.
In the FT4 manufactured by freeman technology, the inflow state of the air flow rate is controlled.

  The toner used in the present invention has a basic fluid energy amount A of 150 mJ to 600 mJ (preferably 150 mJ to 400 mJ, more preferably 180 mJ to 350 mJ). When the basic fluidity energy amount A is less than 150 mJ, the toner has excessive fluidity, so that the toner easily enters the nip of the cleaning blade and easily passes through the cleaning blade. Therefore, the toner that has passed through contaminates the output image or contaminates the charger. On the other hand, when the basic fluidity energy amount A exceeds 600 mJ, the fluidity of the toner decreases and the toner tends to aggregate before the cleaning blade nip. Therefore, the toner and the external additive component of the toner slide between the cleaning blade and the photoconductor. It becomes difficult to reach the rubbing part. For this reason, the frictional force generated when the cleaning blade and the photosensitive member are rubbed increases, and an excessive stress is applied to the scraping portion at the tip of the cleaning blade, leading to chipping of the edge of the cleaning blade, and streaky toner leakage occurs. Toner leakage causes image contamination and charger contamination.

  The toner used in the present invention has a value obtained by dividing the fluidization energy amount B by the basic fluidity energy amount A (fluidization energy amount B / basic fluidity energy amount A, hereinafter referred to as “B / A”). Is called 0.3 or more and 0.9 or less (preferably 0.5 or more and 0.9 or less, more preferably 0.6 or more and 0.8 or less). When (B / A) is less than 0.3, the toner tends to move and becomes unstable, and the toner tends to spill out or rise up. The toner that easily spills or rises from the toner reservoir may contaminate the inside of the image forming apparatus and cause a failure, or may appear as dirt on the output image. On the other hand, if the degassing index (B / A) exceeds 0.9, the toner easily tightens and the movement of the toner decreases, so that the same toner stays in the toner reservoir and the toner that has been excessively stressed is cleaned. It sticks to the edge of the blade, scrapes off the toner, and causes a reduction in scraping performance. If the scraping performance of the blade is reduced, untransferred toner and transfer residual toner on the photoreceptor may pass through the cleaning blade nip, contaminating the charger, mixing colors of the developing machine, and contaminating the output image. It causes image quality degradation.

  The toner used in the present invention includes, for example, at least toner particles and an external additive, and the basic fluid energy amount A and fluidization energy B are determined depending on the type of external additive to be externally added to the toner particles and the toner particles. Control the adhesion structure of the external additive, control the particle size distribution on the fine particle side of the toner particles, add a cleaning aid to the toner particles, control the shape and particle size of the toner particles, non-electrostatic of the toner particles It is also preferable to control the basic fluidity energy amount A and fluidization energy B by combining them.

[External additive]
The external additive that can be used in the present invention is for controlling the controllability of transferability, fluidity, cleaning property, and charge amount as well as control of the basic fluidity energy amount A and fluidization energy B. As the external additive, either inorganic particles or organic particles can be used. Further, a lubricant, an abrasive, etc. can be used in combination.

  Examples of inorganic particles include silica, aluminum oxide, titanium oxide, metatitanic acid, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, and diatomaceous earth. , Cerium chloride, bengara, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, magnesium carbonate, zirconium oxide, silicon carbide, silicon nitride, calcium carbonate, barium sulfate and other metal oxides and ceramic particles, either alone or in combination Can be used.

  Examples of the organic particles include vinyl polymers such as styrene polymers, (meth) acrylic polymers, and ethylene polymers, and various polymers such as ester, melamine, amide, and allyl phthalate. Fluoropolymers such as vinylidene fluoride and particles made of higher alcohols such as unilin.

  As the external additive, inorganic particles are particularly preferable. Among the inorganic particles, at least one selected from silica particles, aluminum oxide, titanium oxide, metatitanic acid, and zinc oxide is preferable. Silica, titanium oxide More preferably, it is silica.

  Here, as a method for controlling the basic fluidity energy amount A and the fluidization energy B by the external additive, the external additive is subjected to silane treatment with 10 or more carbon atoms, silicone oil treatment, or external additive A method of externally adding an irregular external additive or an irregular external additive (inorganic particles of silica, titanium oxide, or aluminum oxide) for controlling the particle diameter is preferably mentioned.

  Specific examples of the silane treatment having 10 or more carbon atoms (preferably 10 to 20, more preferably 10 to 18) include, for example, decylsilane, phenyltriethoxysilane, diphenyldiethoxysilane, decyltrimethoxysilane, and hexamethyl. This is a treatment using disilazane or the like. The amount of silane treated is suitably in the range of 5 to 50 parts by mass with respect to 100 parts by mass of the amorphous external additive.

  Specific examples of the silicone oil treatment include dimethyl silicone oil, methyl hydrogen silicone oil, methylphenyl silicone oil, alkyl-modified silicone oil, α-methylsulfone-modified silicone oil, chlorophenyl silicone oil, and amino-modified silicone. Oil, epoxy-modified silicone oil, carboxyl-modified silicone oil, carbino-modified silicone oil, methacryl-modified silicone oil, mercapto-modified silicone oil, phenol-modified silicone oil, polyether-modified silicone oil, methylstyryl-modified silicone oil, higher fatty acid ester-modified silicone oil , Treatment using fluorine-modified silicone oil or the like. Moreover, the processing amount of silicone oil is suitably in the range of 5 to 50 parts by mass with respect to 100 parts by mass of the amorphous external additive.

  Examples of the amorphous external additive include silica, titanium oxide, and aluminum oxide inorganic particles. Among these, silica is preferably used. Specifically, for example, gas phase method silica (method by high-temperature gas phase hydrolysis of silicon halide (flame hydrolysis method), silica sand and coke in an electric furnace. Anhydrous silica obtained by a vapor phase method such as a method in which gas is heated and reduced by arc and oxidized with air (arc method) is used.

  The number average particle size of the amorphous external additive is preferably 15 nm to 1 μm, more preferably 20 to 800 nm, and still more preferably 30 to 500 nm. In addition, the “indefinite shape” in the amorphous external additive indicates an average circularity described later of 0.830 to 0.960. Examples of the shape suitable as the amorphous external additive include a limping shape, a disk shape, and a rice grain shape, and examples thereof include titanium oxide and metatitanic acid particles.

The amorphous external additive may be externally added at a surface coverage of 10 cov% to 200 cov% (preferably 15 cov% to 100 cov%, more preferably 25 cov% to 70 cov%) with respect to the toner particle surface area.
The surface coverage of the amorphous external additive with respect to the surface area of the toner particles can be calculated according to the following formula. Here, Dt represents the volume average particle diameter of the toner particles, ρt represents the specific gravity of the toner particles, Da represents the number average particle diameter of the external additive, and ρa represents the specific gravity of the external additive.

By externally adding the external additives as described above to the toner particles, the above-mentioned basic fluidity energy A and fluidization energy B can be suitably obtained. Examples of toner particles include a volume average particle size of 3 to 12 μm, a particle size distribution D _84V / D _{50v on the} large particle size side of _1.05 to 1.3, and a particle size distribution D _50p / D _{16p on the} small particle size side. By applying toner particles having a small diameter of 1.1 to 1.35 and a narrow particle size distribution, the basic fluidity energy A and the degassing index can be achieved more suitably.

  Here, the number average particle diameter of the external additive is determined by observing the external additive dispersed on the toner particles using a scanning electron microscope (manufactured by Hitachi, Ltd .: S-4100) and using the photographed image. The diameter of 300 external additive particles can be measured and calculated based on the diameter.

  In addition, two or more types having different particle sizes, such as combining an external additive having a large particle size (for example, volume average particle size of 80 to 300 nm) and an external additive having a small particle size (for example, volume average particle size of 5 to 20 nm). By using external additives, fine irregularities on the surface of the toner particles are controlled, and the amount of fluid energy in the powder rheometer is suitably controlled by adjusting the adhesion between the toner particles and the ease of rolling of the toner particles. can do. Further, for example, by preparing the toner by adding inorganic particles having a large particle size before the inorganic particles having a small particle size, the small particle size inorganic particles coat the surface of the toner particles, and at the same time, outside the large particle size. By coating the surface of the additive, fine unevenness on the outermost surface of the toner can be controlled, and thereby desired fluidity can be secured.

  The amount of the external additive used as a whole is preferably 0.5% by mass or more and 10% by mass or less, more preferably 0.6% by mass or more and 8% by mass or less, based on the toner particles. More preferably, it is 8 mass% or more and 6 mass% or less.

[Cleaning aid]
The toner used in the present invention can control the basic fluidity energy A and fluidization energy B by adding a cleaning aid. Examples of the cleaning aid include fatty acid metal salt powders, higher alcohol powders, fatty acid powders, wax powders, fluorine compound particles, graphite powders, boron nitride powders, mica powders, fatty acid amides such as ethylenebisstearylamide, oleic acid amide, etc. Fatty acid metal salt powder, higher alcohol powder, and fatty acid powder are particularly preferable.
The addition amount of the cleaning aid is preferably 0.05% by mass or more and 5% by mass or less, more preferably 0.1% by mass or more and 3% by mass or less, based on the toner particles. More preferably, it is 15 mass% or more and 1 mass% or less.

The toner (toner particles) used in the present invention includes a binder resin, a colorant, and a release agent.
[Binder resin]
As the binder resin contained in the toner particles, a known resin that can be used for the toner particles can be appropriately selected. Specifically, for example, styrenes such as styrene and chlorostyrene, monoolefins such as ethylene, propylene, butylene and isobutylene, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate and vinyl butyrate, acrylic acid Esters of α-methylene aliphatic monocarboxylic acids such as methyl, ethyl acrylate, butyl acrylate, octyl acrylate, dodecyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate , Homopolymers and copolymers of vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl butyl ether, vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, vinyl isopropenyl ketone, etc. Examples of typical binder resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, and styrene. Mention may be made of maleic anhydride copolymers, polyethylene, polypropylene. Further examples include polyester, polyurethane, epoxy resin, silicone resin, polyamide, and modified rosin.
Among these, styrene- (meth) acrylic acid ester copolymer resins and polyester resins are preferably used.

The molecular weight of the binder resin varies depending on the type of resin, but the weight average molecular weight Mw is preferably 10,000 to 500,000, more preferably 15,000 to 300,000, and 20,000. More preferably, it is -200,000. The number average molecular weight Mn is preferably 2,000 to 30,000, more preferably 2,500 to 20,000, and still more preferably 3,000 to 15,000.
The values of the weight average molecular weight and the number average molecular weight are those measured using gel permeation chromatography (GPC). GPC uses HLC-8120GPC, SC-8020 (manufactured by Tosoh Corporation), and column uses two TSKgel and SuperHM-H (manufactured by Tosoh Corporation, 6.0 mm ID × 15 cm). THF (tetrahydrofuran) is used. As experimental conditions, the sample concentration is 0.5 mass%, the flow rate is 0.6 ml / min, the sample injection amount is 10 μl, the measurement temperature is 40 ° C., and an IR detector is used.

  The glass transition temperature of the binder resin is preferably 40 ° C. to 80 ° C., and preferably 45 ° C. to 75 ° C. from the viewpoints of preventing deterioration of fluidity in a high temperature environment and achieving low temperature fixability. More preferred.

  The glass transition point (Tg) refers to a value obtained by measurement under a temperature rising rate of 10 ° C./min using a differential scanning calorimeter (manufactured by Shimadzu Corporation: DSC-50). The glass transition point is the temperature at the intersection of the extension line of the base line and the rising line in the endothermic part.

[Colorant]
There is no restriction | limiting in particular as a coloring agent contained in a toner particle, The coloring agent known per se can be mentioned, According to the objective, it can select suitably. Examples of the colorant include carbon black, lamp black, Dupont Oil Red, Orient Oil Red, Rose Bengal, C.I. I. Pigment Red 5, 112, 123, 139, 144, 149, 166, 177, 178, 222, 48: 1, 48: 2, 48: 3, 53: 1, 57: 1, 81: 1, C.I. I. Pigment orange 31, 43, quinoline yellow, chrome yellow, C.I. I. Pigment Yellow 12, 14, 17, 93, 94, 97, 138, 174, 180, 188, ultramarine blue, aniline blue, calcoyl blue, methylene blue chloride, copper phthalocyanine, C.I. I. Pigment Blue 15, 60, 15: 1, 15: 2, 15: 3, C.I. I. Pigment Green 7 and malachite green oxalate, nigrosine dye, and the like can be used, and these can be used alone or in combination. These may have been subjected to flashing dispersion processing in advance.

Moreover, magnetic powder can also be used as a coloring agent. Examples of the magnetic powder include known magnetic materials, for example, metals such as iron, cobalt, nickel and alloys thereof, metal oxides such as Fe ₃ O ₄ , γ-Fe ₂ O ₃ , cobalt-added iron oxide, MnZn ferrite, Various ferrites such as NiZn ferrite, magnetite, hematite and other powders can be used, and the surface thereof is treated with a surface treatment agent such as a silane coupling agent or titanate coupling agent, and inorganic compounds such as silicon compounds and aluminum compounds Those coated with a system material or those coated with a polymer may be used.

  The colorant is preferably added in the range of 3% by mass to 15% by mass and more preferably in the range of 4% by mass to 10% by mass with respect to the toner particles. However, when magnetic powder is used as the colorant, it is preferably added in the range of 12% by mass to 48% by mass and more preferably in the range of 15% by mass to 40% by mass with respect to the toner particles. preferable. By appropriately selecting the type of the colorant, each color toner such as yellow toner, magenta toner, cyan toner, black toner, and green toner can be obtained.

(Release agent)
As the release agent contained in the toner particles, for example, paraffin wax and derivatives thereof, montan wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer-Tropsch wax and derivatives thereof, polyolefin wax and derivatives thereof, and the like can be used. Derivatives include oxides, polymers with vinyl monomers, graft modified products, and the like. In addition, alcohols, fatty acids, plant waxes, animal waxes, mineral waxes, ester waxes, acid amides, and the like can be used.

  Specifically, hydrocarbon waxes such as low molecular weight polypropylene and low molecular weight polyethylene, microcrystalline wax, silicone resin, rosins, ester wax, rice wax, carnauba wax, Fischer-Tropsch wax, montan wax, candelilla wax, etc. Is mentioned.

  The ratio of the release agent is preferably in the range of 0.1 to 10% by mass, more preferably in the range of 1 to 8% by mass with respect to the toner particles. If the content of the release agent is less than the above lower limit value, the toner release performance may be reduced and offset may occur. On the other hand, if the content exceeds the upper limit value, the toner charging performance is deteriorated or the heat storage performance is increased. May occur.

[Other additives]
In addition to the above composition, known materials used for developers can be added as appropriate to the toner of the present invention. For example, an internal additive, a charge control agent, an inorganic particle, an organic particle, a lubricant, an abrasive and the like can be mentioned.

Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel, and manganese, alloys, and magnetic materials such as compounds containing these metals.
Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments. As the charge control agent in the present invention, when a wet production method such as a suspension polymerization method, an emulsion polymerization method, an emulsion polymerization aggregation method, or a dispersion polymerization method is used in the toner production method, the stability at the time of aggregation or fusion is affected. From the viewpoint of controlling ionic strength and reducing wastewater contamination, a material that is difficult to dissolve in water is preferable.
Examples of the inorganic particles include all particles usually used as an external additive on the toner surface, such as silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, and cerium oxide. Examples of the organic particles include all particles usually used as external additives on the toner surface, such as vinyl resins, polyester resins, and silicone resins. These inorganic particles and organic particles can be used as fluidity aids, cleaning aids, and the like.
Examples of the abrasive include the aforementioned silica, titanium oxide, alumina, cerium oxide, and the like.

[Production method]
The toner of the present invention attaches or fixes the external additive to the surface of the toner particle by applying a mechanical impact force between the toner particle and the external additive with a stirring device such as a sample mill, a Henschel mixer, a hybridizer, or a nobilta. Can be obtained. At this time, the adhesion state of the external additive can be controlled by controlling temperature, mechanical impact force, and time.

  The toner particles can be produced according to a known production method. There is no restriction | limiting in particular as said manufacturing method, According to the objective, it can determine suitably.

  For example, after pre-mixing a binder resin, a colorant, a release agent, and a charge control agent, if desired, melt-kneading in a kneader, pulverizing after cooling, and vibration sieving machine or wind sieving machine as described above Etc., and can be produced using a kneading and pulverizing method. Further, it can be produced by a wet spheronization method, a suspension granulation method, a suspension polymerization method, an emulsion polymerization aggregation method or the like.

[Physical properties]
(Volume average particle diameter of toner particles)
The volume average particle diameter of the toner particles is preferably 3 μm to 12 μm, more preferably 3.5 μm to 10 μm, still more preferably 4 μm to 9 μm. When the volume average particle size of the toner particles is less than 4 μm, the fluidity is remarkably lowered, so that the developer layer is not sufficiently formed by the layer regulating member or the like, and the image may be fogged or dirtied. On the other hand, if it exceeds 12 μm, the resolution is lowered and a high-quality image may not be obtained, or the charge amount per developer unit weight is lowered, and the layer formation maintenance property of the developer layer is lowered, Fog and dirt may occur in the image.

As a method for measuring the volume average particle diameter of the toner particles, 0.5 to 50 mg of a measurement sample is added to 2 ml of a 5% by weight aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate, as a dispersant, and this is added to the electrolytic solution. Added in 100-150 ml. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute, and the particle diameter is 1.0 to 1.0 by using the Coulter Multisizer-II aperture having an aperture diameter of 50 μm. The particle size distribution of particles in the range of 30 μm is measured. The number of particles to be measured is 50,000.
For the particle size range (channel) obtained by dividing the obtained particle size distribution, the volume cumulative distribution is subtracted from the small particle size side, and the particle size that becomes 50% cumulative is _defined as the volume average particle size D _50v .

(Particle size distribution of toner particles)
The preferred particle size distribution of the toner particles is when the proportion of toner particles having a particle size of 4 μm or less is 45% by number or less, more preferably 40% by number or less, and even more preferably 35% by number or less.
Similarly to the determination of the volume average particle size D _50v , the particle size that becomes 84% cumulative when the volume cumulative distribution is subtracted from the small particle size side is D _84v, and the number cumulative distribution is calculated from the small particle size side. It is preferable that D _84v / D _50v is 1.35 or less, where D _{16p is} the particle size that is 16% cumulative when subtracted, and D _50p (number average particle size) is the particle size that is 50%. More preferably, it is 30 or less. _It is preferable that D 50p _{/ D 16p} is 1.45 or less, more preferably 1.40 or less.

  In order to obtain toner particles having such a particle size distribution, it can be adjusted to a desired particle size distribution by a wind classifier, a centrifugal classifier, an inertia classifier, or a sieve sorter.

  When the particle size distribution of the toner particles is wider than the above range, the fluid energy amount by the powder rheometer described above tends to be out of the specified range.

The particle size distribution of the toner particles is obtained by subtracting the volume cumulative distribution from the small particle size side with respect to the particle size range (channel) obtained by dividing the particle size distribution obtained by the same method as the measurement of the volume average particle size. When the particle size of 84% is _D84v , the cumulative number distribution is subtracted from the small particle size side, the particle size of 50% is _D50p , and the particle size of 16% is _D16p. the particle size distribution index and the volume average particle diameter _{D 84v} / volume average particle diameter _{D 50v,} refers to a value obtained fine powder side particle size distribution index as the number average particle diameter _{D 50p} / number average particle diameter _{D 16p.}

Further, using these, the volume average particle size distribution index (GSDv) is calculated from ^{_{(D 84v / D 16v) 1/2}} , the number average particle size distribution index (GSDp) than _{(D 84p} / D ^{16p) 1/2} Say the calculated value.

(Average circularity of toner particles)
The average circularity of the toner particles is preferably in the range of 0.950 to 0.998 (preferably in the range of 0.955 to 0.980). Below this range, the shape becomes indeterminate, and developability, transferability, durability, and fluidity are deteriorated, resulting in in-machine contamination due to toner spillage. On the other hand, when the average circularity exceeds the above range, the ratio of spherical particles increases, and cleaning properties may become difficult.

  Here, the average circularity is obtained by (circle equivalent perimeter) / (perimeter) [(perimeter of a circle having the same projection area as the particle image) / (perimeter of the particle projection image)] A flow-type particle image analyzer (for example, manufactured by Sysmex Corporation) takes a particle image as a still image by instantly strobe light emission, and forms a very flat flow. FPIA-2100). The number of samplings when obtaining the average circularity is 3500.

(Electrostatic latent image developer)
The toner for developing an electrostatic latent image of the present invention is used as it is as a one-component developer or as a two-component developer. When used as a two-component developer, it is used by mixing with a carrier.

The carrier that can be used in the two-component developer is not particularly limited, and a known carrier can be used. The average circularity is 0.98 or more and 1.00 or less (more preferably 0.98 or more and 0.99). The residual magnetization is 2 emu / g or more and 10 emu / g or less (more preferably 2 emu / g or more and 8 emu / g or less).
Here, the measurement of the residual magnetization of the carrier uses, for example, a vibration sample type magnetometer VSMP10-15 (manufactured by Toei Kogyo Co., Ltd.). The measurement applies an applied magnetic field and sweeps up to 1000 oersted. Next, the applied magnetic field is reduced to create a hysteresis curve on the recording paper. The residual magnetization is obtained from the curve data. In the present invention, the remanent magnetization refers to the magnetic force when the applied magnetic field is once swept up to 1000 Oersted and then the applied magnetic field is decreased and the application of the magnetic field is completed. Specifically, it is obtained by reading the Y intercept at the end of measurement of the hysteresis curve created on the recording paper.

For measurement of the average circularity of the carrier used in the present invention, for example, FPIA-3000 (manufactured by Sysmex Corporation) is used. This system employs a method in which particles dispersed in water or the like are measured by a flow-type image analysis method, and the aspirated particle suspension is guided to a flat sheath flow cell and converted into a flat sample flow by the sheath liquid. It is formed. By irradiating the sample stream with stroboscopic light, the passing particles are imaged as a still image with a CCD camera through the objective lens, and the captured particle image is processed in a two-dimensional image to obtain a projection area and perimeter length. The equivalent circle diameter and circularity were calculated. The equivalent circle diameter is calculated as the equivalent circle diameter from the area of the two-dimensional image for each photographed particle. Image analysis is performed on at least 5,000 or more of the particles photographed in this manner, and the circularity is obtained by the following equation for each photographed particle. In addition, the average circularity is obtained by performing image analysis on 5,000 or more photographed particles and performing statistical processing.
・ Circularity = equivalent diameter circumference length / perimeter length = [2 × (Aπ) ^1/2 ] / PM
In the above formula, A represents the projected area, and PM represents the perimeter. For the measurement, use the LPF mode, and cut and analyze particles that have a particle size of less than 10 μm and more than 50 μm, and that have been imaged by combining a plurality of carrier particles without dispersion. Is preferred.
The measurement sample is prepared as follows, for example. That is, 0.03 g of a carrier is added to and dispersed in a 25 wt% ethylene glycol aqueous solution to prepare a carrier dispersion, and this carrier dispersion may be used as a measurement sample.

When an image is formed using a two-component developer, a carrier made of magnetic particles such as metal oxide is used, but the carrier particles are transferred to the photoconductor in a minute amount during development. The magnetic particles of the carrier are very hard, and when the carrier transferred to the photosensitive member reaches the contact portion with the cleaning blade, it is strongly rubbed against the photosensitive member, which may cause damage to the photosensitive member.
Further, since the carrier also stays in the toner reservoir, the photoconductor scratches become more prominent and may cause image contamination due to latent image leakage.

  However, this problem can be improved by using a carrier having an average circularity of 0.98 or more and 1.00 or less and a residual magnetization of 2 emu / g or more and 10 emu / g2 to 10 emu / g or less. This is because the scratches on the photoreceptor due to the carrier start from the protrusions of the carrier, so that the scratch can be suppressed by bringing the carrier close to a spherical shape. On the other hand, since the spherical carrier has high fluidity, it easily enters the nip portion where the blade edge and the photosensitive member are in contact with each other, and stays in the toner reservoir and is not easily discharged. When a large amount of carrier is accumulated in the toner reservoir, the carrier has a particle size larger than that of the toner, so that the nip portion may be spread and the proper nip shape for scraping and removing the toner may not be maintained. As a result, the scraping property of the blade is reduced and cleaning failure occurs, and untransferred toner and transfer residual toner on the photosensitive member pass through the cleaning blade nip to contaminate the charger, or color mixing of the developing machine, In some cases, the output image is contaminated and the image quality is degraded.

Further, by setting the residual magnetization of the carrier to 2 emu / g or more and 10 emu / g or less, the carrier that has moved onto the photosensitive member continues to have magnetism, and the carriers are aggregated, so that it is easy to be discharged from the toner reservoir and becomes a toner reservoir. It can be prevented from continuing to accumulate.
Carriers with residual magnetization are affected by the magnetic field of the developer transport roll of the developing machine, and retain the magnetic force even after moving onto the photosensitive member. To do. If the residual magnetization is too low, the cohesive force of the carrier is reduced, so that the discharge from the toner reservoir is reduced and the toner tends to accumulate in the toner reservoir. If the remanent magnetization is too high, the cohesiveness of the carrier inside the developing machine becomes too high, the miscibility with the toner decreases, and a poorly charged toner is generated, which may cause toner ejection from the developing machine. is there.

  As a carrier having a remanent magnetization of 2 emu / g or more and 10 emu / g or less as described above, a magnetite carrier, a magnetic powder dispersed carrier in which magnetite fine particles are dispersed in a resin matrix, and the magnetite or magnetic powder dispersed carrier as a core. Further, a resin-coated carrier coated with a resin can be mentioned, and a resin-coated carrier coated with a resin with a magnetite or magnetic powder-dispersed carrier as a core is preferable.

  The mixing ratio (mass ratio) of the toner used in the present invention and the carrier in the two-component developer is preferably toner: carrier = 1: 100 to 30: 100, and more preferably 3: 100 to 20: 100.

(Cleaning means)
The cleaning means according to the present invention has an elastic structure in which one end is fixed to a support made of a rigid body, and the other end has a scraping portion that comes into contact with the image holding body and scrapes off transfer residual toner on the image holding body. A cleaning blade made of a body, and a stay control member attached to the back side of the cleaning blade and blocking the transfer residual toner scraped off by the scraping portion to form a toner pool. Hereinafter, the cleaning means in the present invention will be described.

As shown in FIG. 4, the cleaning unit 6 in the present invention includes a cleaner housing 40 that is disposed in the vicinity of the image carrier (photosensitive member) 1 and opens to the side facing the image carrier 1.
Further, the cleaner housing 40 is provided with a cleaning blade 42 that scrapes (scraps) residual toner T remaining on the surface of the image carrier in a state where the tip 44 contacts the surface of the image carrier. The rear end portion of the cleaning blade 42 is fixed to the cleaner housing 40.

Residual toner T scraped off by the cleaning blade 42 is retained on the back side of the cleaning blade 42 (the side opposite to the side where the image carrier 1 is disposed), and the tip of the cleaning blade 42 and the image carrier 1 are retained. A plate-like retention control member 46 that forms a toner reservoir 50 in contact with the toner reservoir 50 is provided. The lower end portion of the staying control member 46 is fixed to the cleaning blade 42. The longitudinal width of the staying control member 46 is approximately the same as the longitudinal width of the cleaning blade 42. In order to reduce the retention of the scraped toner, the longitudinal width of the retention control member 46 is made shorter than the longitudinal width of the cleaning blade 42 so that the toner can be easily discharged from the end of the retention control member. It is possible to perform control such as opening a hole on the slit in the member to facilitate toner discharge.
The waste toner 48 overflowing from the toner reservoir 50 is stored in the cleaner housing 40. Further, in the configuration of the present invention, there is no member that contacts the untransferred toner image and the transfer residual toner before cleaning, so there is no concern about the adhesion and accumulation of toner on these members, and the dirt that drops off from these members. Does not occur.

As shown in FIG. 5 that, the tip of the cleaning blade 42, the image bearing member 1, and the damming member 46, in cross-sectional area C of the toner reservoir is formed is 0.5 mm ² or more 5 mm ² or less Is preferably 1 mm ² or more and 4.5 mm ² or less, more preferably 2 mm ² or more and 3 mm ² or less. If the cross-sectional area C of the toner reservoir is less than 0.5 mm ² , the ability to store toner is low, and a sufficient toner reservoir may not be formed. If the cross-sectional area C exceeds 5 mm ² , a large amount of toner is stored in the toner reservoir. Therefore, a large amount of toner accumulated during removal or replacement of the cleaning means or the photoconductor may be spilled and stain the periphery.

  The cross-sectional area C of the toner reservoir is a cross-sectional area viewed from the axial direction of the image carrier 1, and includes the tip of the cleaning blade 42, the image carrier 1, the blocking member 46, and the blocking member 46. The area surrounded by a straight line with the tip extended. As for the cross-sectional area C of the toner reservoir, silicone rubber was poured into the toner pool, solidified after standing, taken out and cut, and the cross-sectional area of the toner pool was measured using the cross section. Cutting is performed by dividing the blade into 6 equal parts in the longitudinal direction, and measuring each cross section to obtain an average value to obtain a cross-sectional area of the toner reservoir (note that the retention control member has the same height as the tip of the cleaning blade 42 described below). The length up to the tip of 46 and the length from the same height as the tip of the attachment portion of the cleaning blade 42 of the cleaner housing 40 to the tip of the cleaning blade are also measured at the same measurement location (six in the longitudinal direction). The average value of the measured values.)

  The length D from the same height as the tip of the cleaning blade 42 to the tip of the stay control member 46 is preferably 0.5 mm or more and 5 mm or less, more preferably 1 mm or more and 3 mm or less, and 1.5 mm. More preferably, it is 2.5 mm or less. If the length D is less than 0.5 mm, the ability to accumulate toner is low and a sufficient toner reservoir may not be formed. If the length D exceeds 5 mm, a large amount of toner accumulates in the toner reservoir. In some cases, a large amount of toner accumulated during removal or replacement of the means or the photoconductor may spill and stain the periphery. Here, the length D refers to a distance between a line obtained by extending the tip of the cleaning blade 42 and the tip of the stay control member 46 in the center line in the width direction of the stay control member 46 as shown in FIG.

  The length E from the same height as the tip of the attachment portion of the cleaning blade 42 of the cleaner housing 40 (tip of the support made of a rigid body) to the tip of the cleaning blade 42 is preferably 3 mm or more and 15 mm or less. More preferably, it is 13 mm or less, and further preferably 6 mm or more and 12 mm or less. If the length from the same height as the tip of the support made of a rigid body to the tip of the cleaning blade is less than 3 mm, minute vibrations may not be sufficiently generated and the photosensitive member drive torque may increase. If it exceeds 15 mm, the cleaning blade 42 may be easily turned over. This is because the cleaning blade 42 slightly vibrates when the image carrier 1 is rubbed, and the fine vibrations sequentially release the distortion of the cleaning blade 42 to suppress turning, thereby stabilizing the cleaning blade 42 and the image carrier 1. This is to maintain the pressed state. Here, the length E refers to the distance between the line extending the tip of the cleaner housing 40 and the tip of the cleaning blade 42 at the center line in the width direction of the cleaning blade 42 as shown in FIG.

In the cleaning blade 42, the contact portion 44 of the image carrier 1 preferably has a corner, and the material thereof is preferably hard. Specifically, it is preferable that the Young's modulus of 50 Kg / cm ² or more 220 kg / cm ² or less of hard rubber blades, and more preferably 100 Kg / cm ² or more 160 Kg / cm ² or less. If the Young's modulus is less than 50 kg / cm ² , there is a problem in the durability of the corner portion (blade edge) of the rubber blade having the action of scraping the surface of the image carrier 1. If it exceeds 220 Kg / cm ² , the elastic distortion of the blade edge will be insufficient, and it will be difficult to generate micro-vibration of the blade that stabilizes the scraped state. In some cases, it becomes impossible to remove the toner component, which may cause contamination of other members or cause image smearing.

Next, an example of the image forming apparatus of the present invention will be described with reference to FIG.
FIG. 6 is a schematic configuration diagram showing a full color image forming apparatus of a quadruple tandem system. The image forming apparatus shown in FIG. 6 is a first to first electrophotographic method that outputs yellow (Y), magenta (M), cyan (C), and black (K) images based on color-separated image data. Fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) are provided. These image forming units (hereinafter simply referred to as “units”) 10Y, 10M, 10C, and 10K are juxtaposed at a predetermined distance in the horizontal direction. The units 10Y, 10M, 10C, and 10K may be process cartridges that are detachable from the main body of the image forming apparatus.

Above each of the units 10Y, 10M, 10C, and 10K, an intermediate transfer belt 20 as an intermediate transfer member is extended through each unit. The intermediate transfer belt 20 is provided by being wound around a driving roller 22 and a support roller 24 that are in contact with the inner surface of the intermediate transfer belt 20 that are spaced apart from each other from the left to the right in the drawing. It is designed to travel in the direction toward 10K. The support roller 24 is urged away from the drive roller 22 by a spring or the like (not shown), and a predetermined tension is applied to the intermediate transfer belt 20 wound around the support roller 24. Further, an intermediate transfer member cleaning device 30 is provided on the side of the image carrier of the intermediate transfer belt 20 so as to face the driving roller 22.
Further, each of the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K includes yellow, magenta, cyan, and black contained in the toner cartridges 8Y, 8M, 8C, and 8K. The four color toners can be supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K described above have the same configuration, here, the first unit that forms a yellow image disposed on the upstream side in the intermediate transfer belt traveling direction. 10Y will be described as a representative. Note that the second to fourth units are denoted by reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) in the same parts as the first unit 10Y. Description of 10M, 10C, 10K is omitted.

The first unit 10Y has an image carrier 1Y that functions as a latent image carrier. The periphery of the image carrier 1Y is exposed by a charging roller (charging means) 2Y for charging the surface of the image carrier 1Y to a predetermined potential, and the charged surface is exposed by a laser beam 3Y based on the color-separated image signal. An exposure device (latent image forming means) 3 that forms an electrostatic latent image, a developing device (developing means) 4Y that supplies charged toner to the electrostatic latent image and develops the electrostatic latent image, and intermediates the developed toner image A primary transfer roller 5Y (primary transfer unit) for transferring onto the transfer belt 20 and a photosensitive member cleaning device (cleaning unit) 6Y for removing toner remaining on the surface of the image holding member 1Y after the primary transfer are sequentially arranged. Has been.
The primary transfer roller 5Y is disposed on the inner side of the intermediate transfer belt 20, and is provided at a position facing the image carrier 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rollers 5Y, 5M, 5C, and 5K. Each bias power source varies the transfer bias applied to each primary transfer roller under the control of a control unit (not shown).

Hereinafter, an operation of forming a yellow image in the first unit 10Y will be described. First, prior to the operation, the surface of the image carrier 1Y is charged to a potential of about −600V to −800V by the charging roller 2Y.
The image carrier 1Y is formed by laminating a photosensitive layer on a conductive substrate (volume resistivity at 20 ° C .: 1 × 10 ⁻⁶ Ωcm or less). This photosensitive layer usually has a high resistance (a resistance equivalent to that of a general resin), but has a property that the specific resistance of the portion irradiated with the laser beam changes when irradiated with the laser beam 3Y. Therefore, a laser beam 3Y is output to the surface of the charged image carrier 1Y via the exposure device 3 in accordance with yellow image data sent from a control unit (not shown). The laser beam 3Y is applied to the photosensitive layer on the surface of the image carrier 1Y, whereby an electrostatic latent image of a yellow print pattern is formed on the surface of the image carrier 1Y.

The electrostatic latent image is an image formed on the surface of the image carrier 1Y by charging. The specific resistance of the irradiated portion of the photosensitive layer is lowered by the laser beam 3Y, and the surface of the image carrier 1Y is charged. On the other hand, this is a so-called negative latent image formed by the flow of electric charge while the electric charge of the portion not irradiated with the laser beam 3Y remains.
The electrostatic latent image formed on the image carrier 1Y in this way is rotated to a predetermined development position as the image carrier 1Y travels. Then, at this development position, the electrostatic latent image on the image carrier 1Y is converted into a visible image (developed image) by the developing device 4Y.

  In the developing device 4Y, for example, yellow toner having a volume average particle diameter of 7 μm including at least a yellow colorant and a binder resin is accommodated. The yellow toner is triboelectrically charged by being agitated inside the developing device 4Y, and has a charge of the same polarity (negative polarity) as the charged electric charge on the image holding body 1Y, and a developer roll (developer holding body). ) Is held on. Then, as the surface of the image carrier 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the latent image portion on the surface of the image carrier 1Y, and the latent image is developed with the yellow toner. Is done. The image carrier 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the image carrier 1Y is conveyed to a predetermined primary transfer position.

When the yellow toner image on the image carrier 1Y is conveyed to the primary transfer, a predetermined primary transfer bias is applied to the primary transfer roller 5Y, and electrostatic force directed from the image carrier 1Y to the primary transfer roller 5Y is generated. Acting on the toner image, the toner image on the image carrier 1Y is transferred onto the intermediate transfer belt 20. The transfer bias applied at this time is a (+) polarity opposite to the polarity (−) of the toner, and is controlled to about +10 μA by the control unit (not shown) in the first unit 10Y, for example.
On the other hand, the toner remaining on the image carrier 1Y is removed and collected by the cleaning device 6Y. Further, the composite particles remaining on the photosensitive member are also removed and collected by the cleaning device 6Y. In the cleaning by the cleaning device 6Y, the above-described effects of the present invention are exhibited.

Further, the primary transfer bias applied to the primary transfer rollers 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
Thus, the intermediate transfer belt 20 onto which the yellow toner image has been transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superimposed and transferred in a multiple manner.

  The intermediate transfer belt 20 onto which the four color toner images have been transferred in multiple layers through the first to fourth units is disposed on the image transfer surface side of the intermediate transfer belt 20 and the support roller 24 in contact with the inner surface of the intermediate transfer belt 20. The secondary transfer roller (secondary transfer means) 26 is connected to a secondary transfer portion. On the other hand, a recording sheet (recording medium) P is fed at a predetermined timing into a gap where the secondary transfer roller 26 and the intermediate transfer belt 20 are pressed against each other via a supply mechanism, and a predetermined secondary transfer bias is supplied to the support roller. 24. The transfer bias applied at this time is a (+) polarity opposite to the polarity (−) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P is applied to the toner image, so that the toner image is transferred onto the intermediate transfer belt 20. The toner image is transferred onto the recording paper P. Note that the secondary transfer bias at this time is determined according to the resistance detected by a resistance detecting means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

Thereafter, the recording paper P is sent to a fixing device (fixing means) 28, where the toner image is heated, and the color-superposed toner image is melted and fixed on the recording paper P. The recording paper P on which the color image has been fixed is carried out toward the discharge unit, and a series of color image forming operations is completed. On the other hand, the surface of the intermediate transfer belt 20 to which the toner image has been transferred is cleaned by the intermediate transfer body cleaning device 30. The composite particles remaining on the intermediate transfer belt 20 are removed and collected by the intermediate transfer cleaning device 30. The effects of the present invention described above are also exhibited in the cleaning by the intermediate transfer body cleaning device 30.
The image forming apparatus exemplified above is configured to transfer the toner image onto the recording paper P via the intermediate transfer belt 20, but the present invention is not limited to this configuration, and the toner image is directly transferred from the photoconductor. It may be a structure that is transferred to a recording sheet.

  The image forming apparatus of the present invention uses the toner used in the above-described present invention and includes a cleaning unit in which a toner reservoir is formed. A stable image free from image quality defects such as unevenness in the light portion can be obtained.

<Process cartridge>
The process cartridge of the present invention is detachable from the main body of the image forming apparatus, and develops the electrostatic latent image formed on the image holding body with at least an image holding body and a developer containing toner, and thereby a toner image. Developing means for forming the toner image on the image carrier, and cleaning means for cleaning the transfer residual toner on the image carrier after the transfer. The cleaning means is fixed to a support body having one end made of a rigid body. A cleaning blade made of an elastic body having a scraping part that contacts the image holding member and scrapes the transfer residual toner on the image holding member at the other end, and is attached to the back side of the cleaning blade, A retention control member that retains the transfer residual toner scraped off by the scraping portion to form a toner reservoir, and the toner rotates at an air flow rate of 0 ml / min. The basic fluidity energy A when measured with a powder rheometer under the conditions of a tip speed of 100 mm / sec and a rotor blade entry angle of -5 ° is 150 mJ or more and 600 mJ or less, and the air flow rate is 80 ml / min. After giving a history of deaeration by fluidizing at a tip speed of 100 mm / sec and a rotor blade entry angle of 5 °, an air flow rate of 0 ml / min, a tip speed of the rotor blade of 100 mm / sec, and an approach angle of the rotor blade The fluidization energy B when measured under the condition of 5 ° and the basic fluidity energy amount A are such that (fluidization energy B / basic fluidity energy amount A) is 0.3 or more and 0.9 or less. It is a process cartridge characterized by having.

The developer used in the process cartridge of the present invention is the same as the developer used in the above-described image forming apparatus of the present invention, and the cleaning means included in the process cartridge of the present invention includes the image forming apparatus of the present invention. It is the same as the cleaning unit, and the other image carrier and each unit are preferably the same as the image carrier and each unit of the image forming apparatus of the present invention.
When the process cartridge of the present invention is used, the toner used in the present invention described above is used and a cleaning means for forming a toner reservoir is provided. Thus, a stable image free from image quality defects such as unevenness in the highlight portion can be obtained.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples. In the text, “part” means “part by mass”.

<Measuring method of various characteristics>
First, methods for measuring physical properties of developers and the like used in Examples and Comparative Examples will be described.

-Toner particle size distribution measurement-
The volume average particle diameter of the toner particles was measured as follows.
As a dispersant, 0.5 to 50 mg of a measurement sample was added to 2 ml of a 5% by weight aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate, and this was added to 100 to 150 ml of the electrolytic solution. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute, and the particle diameter is 1.0 to 1.0 by using the Coulter Multisizer-II aperture having an aperture diameter of 50 μm. The particle size distribution of particles in the range of 30 μm is measured. The number of particles to be measured is 50,000. For the particle size range (channel) obtained by dividing the obtained particle size distribution, the volume cumulative distribution is subtracted from the small particle size side, and the particle size that becomes 50% cumulative is _defined as the volume average particle size D _50v . Similarly to the determination of the volume average particle size D _50v , when the volume cumulative distribution is created from the small particle size side, the particle size that becomes 84% cumulative is D _84v, and the number cumulative distribution is calculated from the small particle size side. If the particle size that is 16% cumulative when created is D _16p , and the particle size that is 50% cumulative when creating the number cumulative distribution from the small particle size side is D _50p (number average particle size), then the large particle size the particle size distribution of the side at _D 84v _{/ D 50v,} depicting the particle size distribution of small particle diameter side at _D 50p _{/ D 16p.}

-Measurement of number average particle size of externally added particles-
The number average particle diameter of the external additives is 300 using a photograph taken by observing the external additives dispersed in the form of toner base particles using a scanning electron microscope (manufactured by Hitachi, Ltd .: S-4100). The diameter of the external additive particles was measured and calculated based on the diameter.

(Production of toner particles (1))
-Preparation of resin fine particle dispersion (1)-
-Styrene: 330 parts-n-Butyl acrylate: 30 parts-Acrylic acid: 10 parts-Ion exchange water: 550 parts-Anionic surfactant (Dowfax, manufactured by Dow Chemical Co.): 1.4 parts Under stirring and mixing, 50 parts of ion-exchanged water in which 4.5 parts of ammonium persulfate is dissolved is added, and emulsion polymerization is performed at 72 degrees for 10 hours to disperse resin particles having a weight average molecular weight Mw = 28200. A fine particle dispersion (1) was prepared.

-Preparation of resin fine particle dispersion (2)-
-Styrene: 300 parts-n-Butyl acrylate: 100 parts-Acrylic acid: 20 parts-1,10-decanediol: 7 parts-Anionic surfactant (Dow Fax manufactured by Dow Chemical Company): 4.5 parts While stirring and mixing in a nitrogen atmosphere, 50 parts of ion-exchanged water in which 6 parts of ammonium persulfate was dissolved was added, and emulsion polymerization was performed at 72 ° C. for 10 hours to disperse resin particles having a weight average molecular weight Mw = 26800. A resin fine particle dispersion (2) was prepared.

-Preparation of colorant dispersion-
Carbon black (Mogal L: Cabot): 60 parts Nonionic surfactant (Nonipol 400: Sanyo Chemical Co., Ltd.): 10 parts Ion-exchanged water: 250 parts The above ingredients are mixed and dissolved. A colorant dispersant in which colorant (carbon black) particles having an average particle diameter of 220 nm are dispersed by stirring with a homogenizer (Ultra Turrax T50: manufactured by IKA) for 10 minutes and then dispersing with an optimizer. Was prepared.

-Preparation of release agent dispersion-
Paraffin wax (HNP0190: Nippon Seiwa Co., Ltd., melting point 85 ° C.): 100 parts Cationic surfactant (Sanisol B50: Kao Co., Ltd.): 8 parts Ion-exchanged water: 250 parts or more Is dispersed in a round stainless steel flask using a homogenizer (Ultra Turrax T50: manufactured by IKA) for 10 minutes, and then dispersed with a pressure discharge type homogenizer, and release agent particles having an average particle size of 498 nm. A mold release agent dispersion liquid was prepared.

-Production of toner particles (1)-
The resin fine particle dispersion (1) and the resin fine particle dispersion (2) are mixed at a ratio (mass ratio) of 2: 1. The mixed resin particle dispersion: 300 parts, the colorant dispersion: 70 parts, and the mold release. Agent dispersion liquid: 120 parts, polyaluminum hydroxide (manufactured by Asada Chemical Co., Paho2S): 0.4 part, and ion-exchanged water: 60 parts in a round stainless steel flask with a homogenizer (Ultra Turrax T50: The mixture was dispersed using IKA) and heated to 50 ° C. while stirring the inside of the flask in an oil bath for heating. After holding at 50 ° C. for 30 minutes, the temperature of the heating oil bath was further raised and held at 60 ° C. for 1 hour to prepare a dispersion containing aggregate particles having a D50v of 6.1 μm. Thereafter, 100 parts of the resin fine particle dispersion 1 was further added to the dispersion containing the aggregate particles, and then the temperature of the heating oil bath was raised to 55 ° C. and held for 30 minutes. The dispersion containing the aggregated particles was added with 1N sodium hydroxide to adjust the pH of the system to 7.0, and then the stainless steel flask was sealed and heated to 80 ° C. while continuing stirring using a magnetic seal. And held for 4 hours. After cooling, the toner particles were filtered off, washed four times with ion exchange water, and then lyophilized to obtain a dry powder.

This dry powder was classified using a classifier (EJ30, manufactured by Nippon Steel Mining Co., Ltd.). The classification conditions are as follows: the ejector pressure is 0.1 MPa, the raw material supply amount is 50 kg / H, the position of the classification edge is 15 mm from the Coanda block to the F edge tip, and the distance from the M edge tip to the Coanda block is The toner particles (1) were obtained by setting the blower air volume of fine powder, coarse powder, and medium powder at 5.1, 3.0, and 9.0 Nm3 / min, respectively. The resulting toner particles (1) have a volume average particle diameter D50v of _{6.8μm, D} 84v _/ D _50v is _{1.15, D} 50p _/ D _16p was 1.19.

-Preparation of externally added particles (1)-
A sol-gel silica particle having a number average particle diameter of 135 nm is suspended in a gas phase with a dimethyl silicone oil having a viscosity of 65 cs, and a solution containing dimethyl silicone oil is sprayed on 100 parts of the sol-gel silica particle. After 10 parts of treatment, externally added particles (1) were obtained.

-Preparation of external additive particles (2)-
3 parts of n-decyltrimethoxysilane was treated in a liquid with respect to 100 parts of metatitanic acid having a number average particle diameter of 22 nm to obtain external additive particles (2).

(Production of Toner (1))
100 parts of toner particles (1) and 5 parts of external additive particles (1) are blended for 20 minutes with a powder processing device (Nobilta NOB130, manufactured by Hosokawa Micron Corporation) with a clearance of 3 mm, a peripheral speed of 1000 rpm, and cooling water flowing through the jacket. Then, coarse particles were removed using a sieve having an opening of 45 μm to obtain composite particles (1). 100 parts of this composite particle (1) and 2 parts of externally added particles (2) were added, put into a Henschel mixer, and treated for 10 minutes at a peripheral speed of 15 m / sec while flowing cooling water through the jacket. Coarse particles were removed by sieve to obtain toner (1).

(Preparation of toner particles (2))
The resin fine particle dispersion (1) and the resin fine particle dispersion (2) are mixed at a ratio (mass ratio) of 2: 2, and this mixed resin particle dispersion: 300 parts, a colorant dispersion: 70 parts, release Agent dispersion liquid: 120 parts, polyaluminum hydroxide (manufactured by Asada Chemical Co., Paho2S): 0.4 part, and ion-exchanged water: 60 parts in a round stainless steel flask with a homogenizer (Ultra Turrax T50: The mixture was dispersed using IKA) and heated to 50 ° C. while stirring the inside of the flask in an oil bath for heating. After maintaining at 50 ° C. for 30 minutes, the temperature of the heating oil bath was further raised and maintained at 60 ° C. for 1 hour. After cooling, the toner particles were filtered off, washed four times with ion exchange water, and then lyophilized to obtain toner particles (2). The resulting toner particles (2) have a volume average particle diameter D50v of _{6.6μm, D} 84v _/ D _50v is _{1.21, D} 50p _/ D _16p was 1.27.

(Production of Toner (2))
Add 100 parts of toner particles (2) and 2 parts of external additive particles (2), put them in a Henschel mixer, and treat them for 10 minutes at a peripheral speed of 15 m / sec while flowing cooling water through the jacket. Thus, coarse particles were removed to obtain toner (2).

(Production of Toner (3))
Add 100 parts of toner particles (1) and 3 parts of external additive particles (2), put them in a Henschel mixer, and treat them for 10 minutes at a peripheral speed of 15 m / sec while flowing cooling water through the jacket. Thus, coarse particles were removed to obtain toner (3).

(Production of Toner (4))
100 parts of toner particles (2) and 8 parts of external additive particles (1) are blended for 20 minutes with a powder processing device (Nobilta NOB130, manufactured by Hosokawa Micron Corporation) with a clearance of 3 mm, a peripheral speed of 1000 rpm, and cooling water flowing through the jacket. Then, coarse particles were removed using a sieve having an opening of 45 μm to obtain composite particles B. Add 100 parts of this composite particle B and 1 part of externally added particles (2), put them into a Henschel mixer, and treat them for 10 minutes at a peripheral speed of 15 m / sec while flowing cooling water through the jacket. Coarse particles were removed to obtain toner (4).

-Production of toner particles (3)-
Linear polyester obtained from terephthalic acid, bisphenol A and glycerin (number average molecular weight M _n = 3,000, weight average molecular weight M _w = 10,500) 90 parts, carbon black (Mogal L: manufactured by Cabot): 3 parts 7 parts of paraffin wax were premixed and then kneaded with an extruder, and the resulting slab was rolled, cooled, crushed and then pulverized with a jet mill. Further, classification was performed with a classifier (EJ30, manufactured by Nippon Steel & Mining Co., Ltd.) to remove coarse powder and fine powder, and toner base particles C were obtained. The resulting toner mother particles 1, the volume average particle diameter D50v of _{5.3μm, D} 84v _/ D _50v is _{1.35, D} 50p _/ D _16p was 1.42.

(Production of Toner (5))
Add 100 parts of toner particles (3), 10 parts of externally added particles (1) and 4 parts of externally added particles (2), put them in a Henschel mixer, and let the cooling water flow through the jacket, while the peripheral speed is 15 m / sec. The treatment was performed for 10 minutes under the conditions, and coarse particles were removed with a 45 μm sieve to obtain toner (5).

(Production of Toner (6))
100 parts of toner particles (3) and 5 parts of externally added particles (1) are blended for 20 minutes with a powder processing device (Nobilta NOB130, manufactured by Hosokawa Micron Corporation) with a clearance of 3 mm, a peripheral speed of 1000 rpm, and cooling water flowing through the jacket. Then, coarse particles were removed using a sieve having an opening of 45 μm to obtain composite particles B. Add 100 parts of this composite particle B and 2 parts of externally added particles (2), put them into a Henschel mixer, and treat them for 10 minutes at a peripheral speed of 15 m / sec while flowing cooling water through the jacket. Coarse particles were removed to obtain toner (6).

Preparation of carrier (1) [Preparation of carrier]
(Preparation of magnetic powder-dispersed resin particles (1))
Phenol 50 parts, formalin 75 parts, magnetite (manufactured by Toda Kogyo Co., Ltd., volume average particle size 0.3 μm, sphere treated with 1.0 mass% silane coupling agent: KBM403: manufactured by Shin-Etsu Chemical Co., Ltd.) 550 parts, ammonia 13 parts of water and 100 parts of ion-exchanged water were added, and the temperature was gradually raised to 90 ° C. while mixing and stirring. After reacting and curing for 4 hours, cooling, filtering, washing and drying were performed. 1) was obtained.

(Production of carrier (1))
The following ingredients were used.
“Magnetic powder-dispersed resin particles (1)”: In 100 parts,
・ "Coating layer forming solution (1)"
Toluene: 150 parts Styrene-methyl methacrylate copolymer (styrene: methyl methacrylate mass ratio 70:30, weight average molecular weight 60,000): 5 parts Carbon black (Regal 330; manufactured by Cabot Corporation): 0.3 parts

The above components except the magnetic powder-dispersed resin particles (1) were stirred / dispersed with a stirrer for 60 minutes, and further subjected to ultrasonic dispersion for 10 minutes to prepare a coating layer forming solution (1). Next, this coating layer forming solution (1) and magnetic powder-dispersed resin particles (1) are placed in a fluidized bed (trade name: MP-01SFP, manufactured by POWREC Co., Ltd.), the blade rotation speed is 1000 rpm, and the air volume is 1.2 m ³ /. The carrier (1) was produced by coating at 70 ° C. for a min, a solution protrusion speed of 10 g / min, and passing through a mesh having an opening of 75 μm. Carrier (1) had an average particle diameter of 40.5 μm, an average circularity of 0.987, and a remanent magnetization of 5.2 emu / g.

(Production of carrier (2))
-Preparation of metal oxide particles (2)-
Mix 80 parts of Fe ₂ O ₃ , 20 parts of MnO ₂ and 7 parts of Mg (OH) ₂ , mix / crush with a wet ball mill for 25 hours, granulate and dry with a spray dryer, and then use a rotary kiln. Temporary baking 1 was performed at 750 ° C. for 10 hours to obtain a temporary baking product 2.
The obtained calcined product 2 was pulverized with a wet ball mill for 10 hours to have an average particle size of 5.9 μm, further granulated and dried with a spray dryer, and then heated at 1100 ° C. for 4 hours using a rotary kiln. Firing was performed. After the main firing, Mn—Mg ferrite particles (metal oxide particles (2)) were obtained through a crushing step and a classification step.

(Production of carrier (2))
Similarly to the carrier (1), a coat layer was formed on the metal oxide particles (2) to obtain a carrier (2). Carrier (2) had an average particle size of 39.2 μm, an average circularity of 0.969, and a residual magnetization of 0.6 emu / g.

(Development of developer)
Toners and carriers in the combinations shown in Table 1 were mixed so that the carrier: toner ratio was 91: 9 (mass ratio) to obtain developers.

(Production of cleaning member)
-Production of cleaning member (1)-
A polyester polyol having a molecular weight of 2800 was obtained from 1,9-nonanediol / 2-methyl-1,8-octanediol (molar ratio 68/32) and adipic acid. The ester concentration of this polyester polyol is 6.8 mmol / g. A rubber for a cleaning blade was produced by reacting this polyester polyol with a mixture of 1,3-propanediol and trimethylolethane as a chain extender. The Young's modulus of this rubber was 142 kg / cm ² . This rubber plate was molded into a thickness of 1.2 mm, a width of 15 mm, and a length of 325 mm to obtain a cleaning blade (1) ′.

A polyurethane resin sheet having a thickness of 30 μm, a width of 5 mm, and a length of 325 mm is attached to one side of one end of the cleaning blade (1) ′ so as to protrude 2 mm from the tip of the cleaning blade (1) ′, and the cleaning blade (1) Got.
To have the same configuration as the cleaning unit shown in FIG. 4, the end of the cleaning blade (1) on the same side as the surface on which the urethane resin sheet is attached and the end opposite to the end on which the urethane resin sheet is attached, A cleaning member (1) was prepared by sticking on a plate surface (1 cm × 34 cm) of a plate-like stainless steel plate 1 of 1 cm × 34 cm × 0.3 cm prepared as a rigid body. The tip of the cleaning blade (1) protruded 8 mm from the stainless steel plate to obtain a cleaning member (means) (1).

-Production of cleaning member (2)-
In the production of the cleaning blade (1), a cleaning member (2) was obtained in the same manner as the cleaning member (1) except that the polyurethane resin sheet was stuck so as to protrude 1 mm from the tip of the cleaning blade (1).

-Production of cleaning member (3)-
In the production of the cleaning blade (1), a cleaning member (3) was obtained in the same manner as in the production of the cleaning member (1) except that the polyurethane resin sheet protruded 0.4 mm from the tip of the cleaning blade 1.

-Production of cleaning member (4)-
In the production of the cleaning blade (1), a cleaning member (4) was obtained in the same manner as in the production of the cleaning member (1) except that the polyurethane resin sheet protruded 5.5 mm from the tip of the cleaning blade (1). .

-Production of cleaning member (5)-
In the production of the cleaning blade (1), a cleaning member (5) was obtained in the same manner as in the production of the cleaning member (1) except that the polyurethane resin sheet was not attached.

-Production of cleaning member (6)-
A cleaning member (6) was obtained in the same manner as in the preparation of the cleaning member (1) except that the cleaning blade (1) was protruded 5 mm from the stainless steel plate 1 in the preparation of the cleaning member (1).

-Production of cleaning member (7)-
A cleaning member (7) was obtained in the same manner as the cleaning member 1 except that the cleaning blade (1) was protruded from the stainless steel plate 1 by 14 mm from the tip of the cleaning blade (1).

<Examples 1-9, Comparative Examples 1-6>
Copier manufactured by Fuji Xerox Co., Ltd .: The cleaning member shown in Table 1 is incorporated in the Docu Center Color 400, and the developer which is mixed and combined with the toner and the carrier shown in Table 1 is added to the test developing device. Placed in a container. Furthermore, the Docu Center Color 400 has been modified to be able to output an image even in a single color, the above developing device is installed in the Yellow position, and empty developing devices are installed in the remaining Magenta, Cyan and Kuro positions. did. Further, a computer for controlling image formation was connected to the Docu Center Color 400, and a modified Docu Center Color 400 was produced.
Each cleaning member was attached so as to have the same configuration as in FIG. Specifically, the stainless steel plate 1 of the cleaning member is fixed to the cleaner housing, and the one not attached with the urethane resin sheet is brought into contact with the photosensitive member (image holding member) and attached so as to have the same configuration as FIG. It was.

<Evaluation method>
The modified Docu Center Color 400 was installed in an environment of a temperature of 7 ° C. and a humidity of 12% RH to perform image formation. A maximum of 100,000 highlight images with an image area coverage of 35% were output to a toner supply container while replenishing the developer as appropriate until significant image deterioration was observed, and the number of image quality defects was observed. Specifically, the number of image quality defects such as toner streaks and highlight unevenness was confirmed. Further, the presence or absence of toner contamination inside the image forming apparatus after the test and the presence or absence of significant scratches on the photoreceptor were confirmed. Further, during the test, the test was performed by confirming the presence or absence of abnormal sounds other than the normally generated sounds such as the motor sound of the image forming apparatus and the paper conveyance sound. The results are shown in Table 1. In Table 1, “(A)” indicates basic fluidity energy amount A, “(B) / (A)” indicates fluidization energy B / basic fluidity energy amount A, and “(C)”. Indicates a cross-sectional area of a region surrounded by the cleaning blade, the stay control member, and the surface of the image carrier.

  From Table 1, it can be seen that the image quality defect does not occur for a long time in the example.

It is a figure for demonstrating the measuring method of the fluid energy amount in a powder rheometer. It is a figure which shows the relationship between the vertical load and energy gradient which were obtained with the powder rheometer. It is a figure for demonstrating the shape of the rotary blade used with a powder rheometer. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus of the present invention. FIG. 5 is a schematic configuration diagram enlarging a main part of the image forming apparatus illustrated in FIG. 4. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus of the present invention.

Explanation of symbols

1Y, 1M, 1C, 1K photoconductor (image carrier)
2Y, 2M, 2C, 2K Charging roller 3Y, 3M, 3C, 3K Laser beam 3 Exposure device 4Y, 4M, 4C, 4K Developing device (developing means)
5Y, 5M, 5C, 5K Primary transfer roller 6 Cleaning means 6Y, 6M, 6C, 6K Photoconductor cleaning device (cleaning means)
8Y, 8M, 8C, 8K Toner cartridge 10Y, 10M, 10C, 10K Unit 20 Intermediate transfer belt 22 Drive roller 24 Support roller 26 Secondary transfer roller (transfer means)
28 Fixing device (fixing means)
30 Intermediate transfer member cleaning device 40 Cleaner housing 42 Cleaning blade 44 Front end portion 46 Retention control member 48 Waste toner 50 Toner reservoir

Claims (12)

An image carrier, a charging unit for charging the image carrier, a latent image forming unit for forming an electrostatic latent image on the surface of the charged image carrier, and developing the electrostatic latent image with a developer containing toner. Development means for forming an image on the image carrier, transfer means for transferring the toner image onto a recording medium to form an unfixed transfer image, and the unfixed transfer image transferred on the recording medium Fixing means for fixing the toner, and cleaning means for cleaning the transfer residual toner on the image carrier,
The cleaning means is an elastic body having one end fixed to a support body made of a rigid body, and another end having a scraping portion that contacts the image holding body and scrapes transfer residual toner on the image holding body. A cleaning blade, and a retention control member attached to the back side of the cleaning blade and blocking the transfer residual toner scraped off by the scraping portion to form a toner reservoir,
The toner has a basic fluid energy amount A of 150 mJ or more and 600 mJ or less when measured with a powder rheometer under conditions of an air flow rate of 0 ml / min, a rotating blade tip speed of 100 mm / sec, and a rotating blade approach angle of -5 °. Yes, after giving a history of fluidization and deaeration under conditions of aeration flow rate of 80 ml / min, rotor blade tip speed of 100 mm / sec, and rotation blade approach angle of -5 °, aeration flow rate of 0 ml / min, The fluidization energy B and the basic fluidity energy amount A measured under the conditions of a tip speed of 100 mm / sec and a rotating blade approach angle of -5 ° are (fluidization energy B / basic fluidity energy amount A). An image forming apparatus having a relationship of 0.3 to 0.9. ^2. The image forming apparatus according to claim 1, wherein a cross-sectional area of an area surrounded by the cleaning blade, the staying control member, and the surface of the image carrier is 0.5 mm ² or more and 5 mm ² or less.   The length of the stay control member from the same height as the tip of the cleaning blade to the tip of the stay control member is 0.5 mm or more and 5 mm or less. Electrophotographic image forming apparatus.   4. The cleaning blade according to claim 1, wherein a length from the same height as a tip of the support made of the rigid body to a tip of the cleaning blade is 3 mm or more and 15 mm or less. The electrophotographic image forming apparatus according to claim 1.   The electrophotographic image forming apparatus according to claim 1, wherein the developer includes a carrier.   6. The electrophotographic image forming apparatus according to claim 5, wherein the carrier has an average circularity of 0.98 or more and 1.00 or less and a residual magnetization of 2 emu / g or more and 10 emu / g. The electrostatic latent image formed on the image carrier is developed by at least an image carrier and a developer containing toner, and the toner image is developed on the image carrier. A developing unit for forming, and a cleaning unit for cleaning the transfer residual toner on the image carrier after transfer,
The cleaning means is an elastic body having one end fixed to a support body made of a rigid body, and another end having a scraping portion that contacts the image holding body and scrapes transfer residual toner on the image holding body. A cleaning blade, and a retention control member attached to the back side of the cleaning blade and blocking the transfer residual toner scraped off by the scraping portion to form a toner reservoir,
The toner has a basic fluid energy amount A of 150 mJ or more and 600 mJ or less when measured with a powder rheometer under conditions of an air flow rate of 0 ml / min, a rotating blade tip speed of 100 mm / sec, and a rotating blade approach angle of -5 °. Yes, after giving a history of fluidization and deaeration under conditions of aeration flow rate of 80 ml / min, rotor blade tip speed of 100 mm / sec, and rotation blade approach angle of -5 °, aeration flow rate of 0 ml / min, The fluidization energy B and the basic fluidity energy amount A measured under the conditions of a tip speed of 100 mm / sec and a rotating blade approach angle of -5 ° are (fluidization energy B / basic fluidity energy amount A). A process cartridge having a relationship of 0.3 to 0.9. Cleaning blade and a dwell control member, the cross-sectional area of the region surrounded by the a surface of an image holding member, a process cartridge according to claim 7, characterized in that at 0.5 mm ² or more 5 mm ² or less.   The length of the stay control member from the same height as the tip of the cleaning blade to the tip of the stay control member is 0.5 mm or more and 5 mm or less. Process cartridge.   The length of the cleaning blade from the same height as the tip of the support made of the rigid body to the tip of the cleaning blade is 3 mm or more and 15 mm or less. The process cartridge according to claim 1.   The process cartridge according to claim 7, wherein the developer includes a carrier.   The process cartridge according to claim 11, wherein the carrier has an average circularity of 0.98 or more and 1.00 or less and a residual magnetization of 2 emu / g or more and 10 emu / g.

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