JP4836421B2 - Cleaning device and image forming apparatus - Google Patents

Description

  The present invention relates to an electrophotographic image forming apparatus such as a copying machine, a printer, and a facsimile, and a process cartridge, and more particularly to an electrophotographic apparatus having a cleaning device for cleaning the surface of an image carrier after a transfer process.

  In an electrophotographic image forming apparatus, a toner image formed on an image carrier such as a photosensitive member in a development process is transferred to an intermediate transfer member such as an intermediate transfer belt or directly onto a transfer member such as transfer paper. An image is formed by transferring the toner image onto the surface of the photosensitive member and the intermediate transfer member after transfer of the toner image. For this reason, a cleaning device for removing residual toner from the photosensitive member and the intermediate transfer member is provided. Various types of cleaning devices are known, and in addition to a cleaning blade and a cleaning roller made of an elastic member, a fur brush, a magnetic brush, and the like can be used. Among them, the cleaning blade is widely put into practical use because it has a simple configuration, can be easily downsized, and is advantageous in terms of cost.

However, the cleaning blade has the following problems. When the frictional force between the cleaning blade and the surface of the object to be cleaned such as the image carrier increases or the contact angle of the blade increases, the tip of the cleaning blade is caught in the moving direction of the surface of the object to be cleaned, temporarily. Or, it may be deformed so as to be permanently turned up.
As a countermeasure against this, Patent Document 1 proposes a method in which a powder lubricant is applied between the blade edge and the image carrier to reduce the frictional force with the image carrier and prevent entrainment. Further, Patent Document 2 proposes a method in which a notch is generated by providing a notch in the vicinity of the attachment member of the cleaning blade to facilitate the bending deformation of the blade.

In recent years, however, toner particles have been made smaller and spherical to improve image quality. Polymerized toners such as suspension polymerization and emulsion polymerization, and toners subjected to spherical treatment by hot air flow and fluidized granulation are now available. There is a problem in that when a toner having a spherical shape or a reduced particle size is used, an image forming apparatus including various cleaning devices is liable to cause an image defect due to a cleaning defect.
As countermeasures, Patent Documents 3 to 6 use various static elimination means for spherical toner remaining on the image carrier after the transfer process to reduce the charge amount of the residual toner and improve the cleaning performance. .
However, newly providing the static eliminating means directly leads to an increase in the number of parts and an increase in manufacturing cost.

Therefore, many cleaning devices using a cleaning roller or a cleaning brush have been proposed. For example, Patent Document 7 discloses a recovery cleaning roller in a cleaning device that applies a predetermined voltage to each of a cleaning brush and a recovery cleaning roller and recovers residual toner on the surface of the photosensitive drum to the surface of the recovery cleaning roller via the cleaning brush. A magnetic body disposed at a predetermined distance from the inner peripheral surface of the recovery cleaning roller inside the recovery cleaning roller below the horizontal plane including the axis of the tip, or a tip on the surface of the recovery cleaning roller near the magnetic body Printing is performed with a configuration in which one of the magnetic blades that are disposed opposite to each other and scrapes the residual toner collected on the surface of the collection cleaning roller as the collection cleaning roller rotates is a magnet. Prevents quality degradation and cleaning device life It has been proposed that long.
Further, in Patent Document 8, in a cleaning device for an electrophotographic apparatus provided with a cleaning brush for cleaning a portion to be cleaned and a collection roll for removing and collecting dust adhering to the cleaning brush, the cleaning brush is cleaned during non-cleaning operation. The cleaning brush is rotated in the direction opposite to that during the cleaning operation to prevent the dust adhering to the cleaning brush from being scattered outside the cleaning device and extending the life of the cleaning brush. Etc. have been proposed.
However, in such a cleaning apparatus that collects the residual toner on the surface of the drum-shaped photoconductor of the image carrier on the surface of the recovery cleaning roller via a cleaning roller or a cleaning brush, even if the initial cleaning performance is good The performance of the cleaning roller and the cleaning brush decreases with time due to use over time. That is, as the transfer residual toner is removed, the toner gradually adheres to the cleaning roller, or accumulates in the cleaning brush and becomes clogged. In the cleaning roller and the cleaning brush in such a state, the performance of removing the transfer residual toner is lost, and the function as the cleaning member cannot be performed.

  As described above, the conventional cleaning device is difficult to clean the toner having a spherical or small particle size due to high image quality, and the use of the toner having the spherical or small particle size makes the cleaning device large and costly. There is a problem that leads to high.

JP-A-10-304060 JP 2002-55577 A JP-A-9-96965 JP-A-9-114232 Japanese Patent Laid-Open No. 9-274364 Japanese Patent Laid-Open No. 11-84878 Japanese Patent Laid-Open No. 5-18836 JP-A-6-167912

  The present invention has been made in view of the above-mentioned problems, and the object of the present invention is to involve the tip of the cleaning blade while having a stable and good cleaning performance especially for a spherical toner. It is an object of the present invention to provide a cleaning device capable of preventing, an electrophotographic image forming apparatus and a process cartridge capable of stably obtaining a high-quality image by using the cleaning device.

  As a result of intensive studies, the present inventors have found that in a cleaning device using a cleaning blade, there is no protrusion of the blade portion that has existed in the past with respect to the support portion, and the blade has a high hardness and the arm rotates (changes direction). And a mechanism (constant force applying means) that applies a constant pressure using a spring, it is resistant to entrainment without impairing the ability to follow the surface to be cleaned, and to the spherical toner. The inventors have found that a cleaning blade having a stable and good cleaning property can be obtained, and the present invention has been achieved.

That is, the above-mentioned problem is (1) “a cleaning device that removes toner on the surface of the object to be cleaned with a cleaning blade, and the toner is a spheroidized toner in a manufacturing process or a post-manufacturing process. The cleaning device includes a blade portion that performs cleaning and an arm portion, and the arm portion connects the front half of the arm that supports the blade portion, the rear half of the arm, and the front half of the arm and the rear half of the arm. The rotary shaft portion has a stop angle adjusting mechanism that adjusts the angle between the front half portion of the arm and the rear half portion of the arm around the shaft portion. A constant force applying means for applying a constant force to be always brought into contact with the surface of the object to be cleaned with a predetermined pressing force, and the blade portion is a tip portion of the first half of the arm It is fixed and is in close contact with the front half of the arm on the surface opposite to the surface in contact with the surface of the object to be cleaned, and the tip of the front half of the arm protrudes from the tip of the cleaning blade or has no step. (2) “The front half of the arm has a pressure assisting member for assisting in pressurization at a position in contact with the rear end of the blade. (3) “The rubber hardness (JIS K6301A) of the cleaning blade is 70 to 100”. (1) or (3) The cleaning device according to item 2), (4) “The friction coefficient of the cleaning blade against the surface of the object to be cleaned is 0.5 or less,” (1) to (3), Noisy The cleaning device according to any one of the above, "(5)" a constant force applying means for applying a constant force of the latter half of the arm has a mechanism for applying a force to the latter half of the arm from a plurality of directions. (6) “The toner has a circularity represented by the following formula (I) of 1.0 to 1.0”. 1.4, and the flatness represented by the following formula (II) is 1.0 to 1.4, wherein the flatness is any one of the items (1) to (5) Cleaning device;
Circularity = {(peripheral length of particle) ² / (projected area of particle)} × (1 / 4π) (I)
Flatness = {(maximum length of particle) ² / (projected area of particle)} × (π / 4) (II) ”, (7)“ The cleaning blade and a cleaning roller or a cleaning brush are used in combination. This is solved by the “cleaning device according to any one of items (1) to (6)”.
Further, the above-mentioned problems are solved by (8) “image carrier for carrying at least a toner image, charging device for charging the image carrier, and exposure device for forming an electrostatic latent image on the image carrier. A developing device for forming a toner image on the image carrier, a transfer device for transferring the toner image formed on the image carrier to a transfer member, and a residue on the surface of the image carrier or intermediate transfer member by a cleaning blade. An image forming apparatus having a cleaning device to be removed, wherein the cleaning device is the cleaning device according to any one of (1) to (7). Achieved by "equipment".
Further, the above problem is (9) “Image carrier and cleaning device and at least one device selected from a charging device, an exposure device, and a developing device are integrally supported and detachable from the main body of the image forming apparatus. In a certain process cartridge, the cleaning device is the cleaning device according to any one of the items (1) to (7), and is detachable from the image forming apparatus. Achieved by:

  According to the cleaning device of the present invention, there is no protrusion called a free length of the cleaning blade, a high-hardness cleaning blade, arm rotation (direction change), and a mechanism that applies constant pressure using a spring (constant) In combination with the force imparting means, it is possible to prevent the blade tip from being caught and to perform stable and good cleaning on the spherical toner.

Hereinafter, the present invention will be described in more detail.
First, the member to be cleaned in the present invention mainly indicates a photosensitive member or an intermediate transfer member in an electrophotographic apparatus.
The cleaning device of the present invention is configured to remove the residual toner on the surface of the photosensitive member or the intermediate transfer member with a cleaning blade, and the toner used is a toner having a spherical shape. Spherical toner is more likely to rotate on the surface to be cleaned during blade cleaning than toner generated by the conventional pulverization method, and the problem is that the cleaning blade is pushed through the cleaning blade by rotational force and causes a so-called cleaning failure. It has become. The cleaning device of the present invention increases the density of the tip by applying an appropriate pressure to the tip of the cleaning blade, and further increases the hardness of the blade to reduce the deformation of the blade against the pushing up of the toner, thereby making it spherical. It is strong against blade slippage due to the rotation of the toner, and it is possible to prevent poor cleaning of the spherical toner.

Hereinafter, the cleaning device of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a cross-sectional view of the blade portion and the arm portion of the cleaning device of the present invention.
The blade portion used in the cleaning device of the present invention is preferably made of a rubber elastic body, particularly polyurethane rubber, and the arm portion preferably has a predetermined rigidity such as metal.
The cleaning blade used in the cleaning device of the present invention has a configuration in which the blade portion (1) does not protrude from the conventional cleaning blade support portion (2). The protruding portion of the blade portion (1) with respect to the support portion (2) is called a so-called free length, but when the free length is long, the pressure applied to the blade tip during cleaning greatly depends on the material characteristics of the blade. For example, when the Young's modulus of the blade is low and the free length is long, the pressure transmitted to the tip is very small compared to the pressure applied to the entire blade. Requires a very large force on the entire blade. In addition, when the pressure applied to the blade is increased or the amount of toner entering the contact portion is small, the frictional force between the tip of the blade (1) and the pair to be cleaned becomes strong, and the tip of the cleaning blade is cleaned. Since the blade is pulled strongly in the moving direction of the body, the entire cleaning blade may be caught particularly when the blade is deformed so as to be temporarily or permanently turned and the free length is long.
In the cleaning blade of the present invention having no free length, the pressure applied to the entire blade is easily transmitted to the tip, and the entire blade can be cleaned at a lower pressure than when there is a free length. The cleaning property can be improved while preventing the phenomenon.

An example of a cleaning device using the blade part and the arm part is shown in FIG.
In FIG. 2, the cleaning device (12) includes a blade part (1), an arm front half part (2), an arm rear half part (3), a rotating shaft part (4), a constant force applying means ( 6), a support portion (7), auxiliary cleaning means (9) made up of rollers and brushes, and waste toner collecting means (10). In the drawing, the support portion (7) is arranged in the cleaning device, but it is not necessarily arranged in the device, and the same effect can be obtained even when arranged in the machine body.

  In the cleaning device (12), the blade portion (1) and the arm portion are arranged in the above-described configuration, and a sponge or the like is disposed on the upstream side in the rotation direction of the photosensitive member (14) with respect to the blade portion (1). Auxiliary cleaning means (9) comprising a roller or a brush of magnetic material carrier particles by magnetism or a brush of insulating fiber or the like is disposed so as to contact the photoconductor (14). The photosensitive member (14) in contact with the cleaning device (12) rotates at a predetermined speed in the direction of the arrow in the figure, and a part of the transfer residual toner is an auxiliary cleaning means (9) composed of a roller, a brush and the like. ) And the remainder is scraped off by the blade part (1). Thus, the cleaning efficiency can be further improved by using the cleaning blade and the cleaning brush in combination with the cleaning blade. Furthermore, the charge of the residual toner can be controlled by applying a voltage to the auxiliary cleaning means (9). In addition, even when another object to be cleaned such as an intermediate transfer member is disposed at the position of the photosensitive member (14), the same effect can be obtained with the same configuration.

The cleaning blade that eliminates the free length and is applied with a pressure that increases the density of the tip of the blade is strong against the push-up of the blade due to the rotation of the spherical toner, and can improve the cleaning property of the spherical toner. However, the cleaning blade having no free length does not have a force escape area in the normal direction of the tangent to the surface of the photoreceptor (14), and the following problems become significant.
That is, in blade cleaning, when the object to be cleaned is in the form of a drum, the frictional force in the longitudinal direction of the blade increases greatly due to slight eccentricity of the drum and the amount of toner adhering during cleaning. In this case, damage to the photosensitive member and extreme entrainment of the blade occur. If cleaning is continued in such a state, there are many cleaning failures and further problems such as a loss of the tip of the cleaning blade occur. Therefore, the cleaning device of the present invention uses an arm portion including an arm first half portion (2), an arm rear half portion (3), and a rotating shaft portion (4) for a blade portion (1) having no free length. The rotating shaft portion (4) is rotatably fixed and supports the arm front half (2) and the arm rear half (3).
In other words, in a non-limiting manner, the shaft is pivotally supported by a shaft projecting from the casing wall into the inside of the sinus, and the angle between the arm front half (2) and the arm rear half (3) is kept constant. Keep and support. The stopping angle between the arm front half part (2) and the arm rear half part (3) can be adjusted, changed, and fixed again. The arm portion includes a means (6) for applying a constant force to the rear half portion (3) of the arm so that pressure is applied to the blade portion (1) by a rotational movement about the rotation shaft portion (4). Therefore, a constant pressure can be applied to the tip of the blade part (1) and the surface of the photoreceptor (14), generation of extremely large frictional force can be prevented, and good cleaning properties can be maintained. Can do. In FIG. 2, the means (6) for applying a constant force is arranged between the support part (7) and the rear arm part (3) and pulls the rear arm part (3) with a constant force. . In addition, as shown in FIG. 3, means (6) for applying a constant force is arranged between the support part (7) and the rear arm part (3) to press the rear arm part (3) with a constant force. Configuration is also possible.
Further, as shown in FIG. 4, a means (6) for applying a constant force is arranged from a plurality of directions so that a constant force is applied to the arm portion comprehensively. Since the arm is held in the rotational direction in which the tip of 1) is pulled in the moving direction of the photosensitive member (14), cleaning can be performed more stably. The means (6) for applying a constant force is a metal coil spring, so that its function can be exhibited easily at low cost.

  As shown in FIG. 1, the cleaning device of the present invention further includes a pressure assisting member (5) at a position in contact with the rear end portion of the blade portion (1) in the arm first half portion (2). The pressure can be easily transmitted to the tip, and the tip can be densified.

  The cleaning device of the present invention has a mechanism for adjusting the angle formed by the arm first half (2) and the arm rear half (3) with the rotation shaft (4) as a center. Thereby, by setting an optimal angle according to the arrangement position of the apparatus and the type and state of the object to be cleaned, it is possible to prevent the cleaning blade from being caught and defective in cleaning to various objects to be cleaned.

In the cleaning device of the present invention, the blade part (1) is preferably a rubber elastic body, particularly polyurethane rubber, which is prepared by preparing a urethane prepolymer using a polyol and a polyisocyanate, and adding a curing agent thereto. It is manufactured by molding while cross-linking and curing and aging at room temperature.
In the cleaning device of the present invention, the blade part (1) has a rubber hardness (JIS K6301A) of 70-100. By setting the hardness of the blade part (1) in the range of 70 to 100, it is difficult to be deformed by the pushing up of the blade due to the rotation of the spherical toner, and the cleaning property of the spherical toner can be improved. Further, increasing the hardness of the cleaning blade can facilitate the reduction of friction on the surface of the cleaning blade. If the hardness of the blade part (1) is less than 70, the spherical toner will sink between the blade and the object to be cleaned at the time of blade cleaning, and cleaning failure tends to occur. Further, means such as a slide hole for adjusting and correcting the length ratio of the arm front half (2) and the arm rear half (3) can be provided in the arm front half (2) and the arm rear half (3).

The cleaning blade used in the cleaning device of the present invention is preferably set so that the coefficient of friction with respect to the object to be cleaned is 0.5 or less. The friction coefficient μ between the cleaning blade and the surface of the object to be cleaned is usually measured by a surface property test apparatus (model HEIDON-14) manufactured by HEIDON when the object to be cleaned is in the form of a sheet, flat plate or endless belt. . However, in practice, the photosensitive drum incorporated in the electrophotographic image forming apparatus is mainly a photosensitive drum. In this case, the measurement of the coefficient of friction μ between the cleaning blade and the surface of the cleaning target is a rotational torque T (kg) of the photosensitive drum. -It is calculated | required by the measurement of cm). That is, the rotational torque T1 (kg · cm) of the photosensitive drum itself and the rotational torque T2 (kg · cm) of the photosensitive drum in which the blade cleaning member is pressed against the load F (kg) are measured and calculated by the following formula. Desired.
μ = (T2−T1) / (F · γ) (where γ is the radius (cm) of the photosensitive drum)

  When the coefficient of friction between the cleaning blade and the object to be cleaned decreases, the force with which the cleaning blade is pulled in the direction of movement of the object to be cleaned decreases. Thus, the reciprocating motion is reduced. By setting the friction coefficient to 0.5 or less, the occurrence of the cleaning blade is prevented and the reciprocation of the cleaning blade is reduced, so that the residual toner can be cleaned well. In addition, abnormal noise due to excessive frictional force of the cleaning blade, wear and chipping at the tip of the cleaning blade are reduced, and durability is improved. When the coefficient of friction is greater than 0.5, the above-described problems occur, and cleaning defects are particularly noticeable with spherical toners.

The cleaning means of the present invention is excellent in space saving because of the blade cleaning system, and the cleaning device (12) of FIG. 2 is suitable for being configured to be detachable from the image forming apparatus main body as a process cartridge.
In recent years, in order to cope with the digitization of images, the reproducibility of dots forming images has been required, and the uniformity of the toner that forms dots has led to the progress of toner spheroidization and particle size reduction. It is out.

  As the toner used in the image forming apparatus having the cleaning device of the present invention, a toner that has been spheroidized in a manufacturing process or a post-manufacturing process is used. The toner spheroidized in the post-manufacturing process is, for example, a resin or colorant, which is a constituent material of the toner, mixed and stirred, melted and kneaded, pulverized and classified, and the pulverized toner produced by heat or mechanical force. The spheroidized toner and the spheroidized toner in the production process are toners produced by a polymerization method such as a dispersion polymerization method, a suspension polymerization method, or an emulsion polymerization method. In particular, the polymerization method is excellent in terms of toner shape and particle diameter controllability, productivity and the like, and is also suitable as a method for producing the toner used in the present invention.

From the viewpoint of forming a high-quality image, the toner used in the present invention is preferably particles close to a sphere, and the circularity represented by the following formula (I) is 1.0 to 1.4. It is preferable that the flatness represented by this is 1.0-1.4.
Circularity = {(peripheral length of particle) 2 / (projected area of particle)} × (1 / 4π) (I)
Flatness = {(maximum length of particle) 2 / (projected area of particle)} × (π / 4) (II)
Here, the peripheral length of the particles is the peripheral length in the two-dimensional projection image of the toner particles, and the maximum length of the particles is the absolute maximum length in the two-dimensional projection image of the toner particles.

  In the present invention, the shape factor is, for example, FE-SEM (S-4500) manufactured by Hitachi, Ltd., 100 toner images magnified 1000 times are sampled randomly, and the image information is, for example, image processing software (Media Cybernetics). It is a value calculated by performing analysis using Image-Pro Plus). This shape factor approaches 1 as it approaches a true sphere. If the circularity and flatness exceed 1.4, the dot formation of the image becomes non-uniform and the graininess of the image deteriorates.

  The toner used in the present invention preferably has a volume average particle diameter of 1 to 7 μm. The volume average particle diameter of the toner is determined by Coulter Multisizer measurement manufactured by Coulter Electric. A fine powder toner having a toner particle diameter of less than 1 μm is liable to cause image defects. If the volume average particle diameter exceeds 7 μm, it is difficult to meet the demand for high resolution electrophotographic images.

  In the present invention, a toner whose surface is coated with an external additive is preferably used. Based on the results of measuring the adhesion force and charge amount of various toners whose surfaces were coated with the external additive, the present inventors determined that the adhesion force between the toner and the photoreceptor is the material of the external additive, the particle size, and the external additive. It has been found that it varies depending on the coverage. For this reason, in order to reduce the adhesion between the toner and the photoconductor, satisfy the conditions for good cleaning and stable and good images, the external additive material, particle size and external additive coverage must be set. It is necessary to select and adjust appropriately. The external additive coverage is a ratio of the external additive coating area to the surface area of one toner particle, and can be measured by image analysis of an electron microscope image of the toner surface.

  As the external additive used in the present invention, known organic fine particles and inorganic fine particles can be used, and as the inorganic fine particles, it is particularly preferable to use at least one of silica, titanium, and alumina. It is. In the case of these inorganic fine particles having hygroscopicity, those subjected to a hydrophobization treatment are preferably used in consideration of environmental stability. The hydrophobizing treatment can be performed by reacting the hydrophobizing agent with the fine powder at a high temperature. There is no restriction | limiting in particular as a hydrophobization processing agent, For example, a silane coupling agent, silicone oil, etc. can be used.

As the particle diameter of the external additive, those having an average primary particle diameter of 5 nm to 150 nm are used.
The adhesion force between the toner and the photoreceptor tends to decrease and saturate as the external additive coverage increases, and the external additive coverage dependency and saturation value depend on the material and particle size of the external additive. For this reason, the appropriate range of the external additive coverage varies depending on the material and particle size of the external additive, but it is preferable to adjust the external additive coverage to at least 10 to 90%. If the external additive coverage is less than 10%, it is difficult to make the adhesive force between the toner and the photoreceptor appropriate, which causes an increase in transfer residue. On the other hand, when the external additive coverage exceeds 90%, the external additive is extremely easily separated from the toner, and the constituent members of the image forming apparatus such as the photosensitive member are easily damaged.

Moreover, the external addition method of the external additive used for this invention can use the well-known external addition method using various mixing apparatuses, such as a V-type blender, a Henschel mixer, and a mechano-fusion.
Next, the photoconductor used in the image forming apparatus of the present invention will be described.
When considering blade cleaning as shown in FIG. 2, the surface energy on the surface of the photoreceptor (14) can be reduced to reduce the adhesion and frictional force between the toner and the photoreceptor, and the rotational force of the spherical toner during blade cleaning. Therefore, the cleaning property can be improved.

The contact angle between the photoreceptor used in the image forming apparatus of the present invention and water is preferably 90 ° or more. When the contact angle is less than 90 °, the adhesion force between the toner and the photosensitive member is large, and a defective image is likely to be generated due to an increase in cleaning failure caused by slipping through the blade during cleaning or a decrease in transfer rate.
The contact angle in the present invention was measured using an automatic contact angle meter CA-W manufactured by Kyowa Interface Science Co., Ltd.
As a method for reducing the surface energy of the surface of the photoconductor, a material having a low surface energy is added to the material constituting the surface of the photoconductor, or a material having a low surface energy is given a concentration distribution in the depth direction of the layer. There is a way to make it exist.

As the material having a small surface energy, one or more selected from the group consisting of tetrafluoroethylene, hexafluoropropylene, trifluoroethylene, chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride, and perfluoroalkyl vinyl ether -Containing polymer or copolymer, metal soap such as zinc stearate, aluminum stearate, iron stearate, dimethyl silicone oil, methyl phenyl silicone oil, methyl hydrogen polysiloxane, cyclic dimethyl polysiloxane, alkyl modified silicone oil , Polyether modified silicone oil, alcohol modified silicone oil, fluorine modified silicone oil, amino modified silicone oil, mercapto modified silicone oil, epoxy modified silicone N'oiru, carboxyl-modified silicone oil, silicone oils such as higher fatty acid-modified silicone oil, titanium oxide, silica, aluminum oxide, zirconium oxide, tin oxide, tin oxide doped with antimony oxide, and metal oxides such as indium oxide.
These materials having a small surface energy may be added to the outermost layer, or a concentration distribution may be provided in the depth direction of the layer so as to increase the concentration of the low surface energy material on the surface side.

There is also a method of reducing the surface energy of the surface of the photoreceptor by applying a water repellent material or the like to the surface of the photoreceptor.
Water-repellent substances include dimethyl silicone oil, methyl phenyl silicone oil, methyl hydrogen polysiloxane, cyclic dimethyl polysiloxane, alkyl modified silicone oil, polyether modified silicone oil, alcohol modified silicone oil, fluorine modified silicone oil, amino modified silicone. Silicone oils such as oil, mercapto-modified silicone oil, epoxy-modified silicone oil, carboxyl-modified silicone oil, and higher fatty acid-modified silicone oil.
Amino group-containing silane coupling agents such as γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxy Silane coupling agents containing a mercapto group such as silane, coupling agents containing an epoxy group such as γ-glycidoxypropyltrimethoxysilane, or fluorine-containing silane coupling agents.
Isopropyltriisostearoyl titanate, isopropyltri (N-aminoethyl-aminoethyl) titanate, isopropyltri, (dioctylpyrophosphite) titanate, tetraoctylbis (ditridecylphosphite) titanate, tetraoctylbis (ditolyldecylphosphite) ) Titanium coupling agents such as titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, isopropyltrioctanoite titanate, and the like.
By diluting these materials in an appropriate solvent such as alcohol and applying the solution to the outermost surface of the photoconductor, the surface of the photoconductor is reduced in surface energy, and the condition of the contact angle can be satisfied.

Hereinafter, although embodiment of this invention is described, this invention is not limited at all by these examples.
<Embodiment>
FIG. 5 shows an example of an image forming apparatus according to the present invention.
The image forming apparatus shown in FIG. 5 is a four-color full-color electrophotographic image forming apparatus, and includes a plurality of image forming units (13a), (13b), (13c), (13d) and an intermediate transfer belt (22) ( The toner images formed on the photosensitive drums are temporarily transferred onto the intermediate transfer belt (22) in order and superimposed on each other, and then the toner images are transferred onto the transfer material (24). Secondary transfer is performed at once, and the toner image is fixed on the surface of the transfer material (22) by the fixing device (25) to obtain an image.

  FIG. 5 is a longitudinal sectional view showing a schematic configuration of the entire image forming apparatus. In this image forming apparatus, the spherical toner described above is used, and the cleaning device (12) of the present invention is provided for each unit. As an example of the toner used in this image forming apparatus, a resin prepared by mixing and stirring a constituent material such as a resin or a colorant, melt-kneading, pulverizing and classifying the prepared toner in a hot air stream, the softening point transition of the binder resin is performed. The toner is spheroidized by heating to the above temperature and further classified. The toner has a volume average particle size of 5.0 (μm), the above-described circularity is 1.16, and the flatness is 1.12. In the toner particles, silica treated with hydrophobicity (average primary particle diameter 25 nm) is 1.0% by weight of the toner amount, and titanium oxide treated with hydrophobicity (average primary particle diameter 15 nm) is 1.0 weight of the toner amount. %, And the mixture was stirred and mixed with a Henschel mixer. The external additive coverage measured by image analysis of the electron microscopic image of the toner surface is 40%. The physical properties of the blade part 1 are rubber hardness (JIS K6301A): 90, 300% modulus: 130 kg / cm2, and rebound resilience: 30%.

  The image forming apparatus shown in FIG. 4 includes four image forming units (13a), (13b), (13c), (13) from the upstream side to the downstream side along the moving direction (arrow direction) of the intermediate transfer belt (22). 13d) is provided. The image forming unit forms magenta, cyan, yellow, and black toner images from the upstream. Since these unit configurations are the same, a magenta image forming unit (13a) will be described below as an example. In the image forming unit (13a), a cylindrical photoconductor (14) is rotationally driven in the direction of the arrow at a predetermined process speed. (15) is a charging device, which is installed so as to face the photoconductor (14), and uniformly charges the photoconductor (14) to a predetermined potential having a negative polarity. (16) is an exposure device, which exposes the image portion with optical information corresponding to each color toner obtained by color-separating the input image on the photoreceptor (14) charged by the charging device (15), An electrostatic latent image is formed. The electrostatic latent image formed in this way is visualized as a toner image by attaching charged toner to the developing device (17).

Next, the intermediate transfer belt (22) is pressed against the photoconductor (14) with a predetermined pressing force, and has a peripheral speed equal to or substantially equal to the peripheral speed of the photoconductor (14). The photosensitive member (14) is driven to rotate in the forward direction with respect to the rotational direction of the photoconductor (14), and a constant voltage or a constant current controlled voltage having a polarity opposite to the normal charging polarity of the toner is applied. The toner image formed on the surface of the photoreceptor (14) is transferred to the surface of the intermediate transfer belt (22) at the pressure contact portion. Thereafter, the toner image is discharged out of the apparatus as an image through the above-described process. The transfer residual toner adhering to the surface of the photoreceptor (14) after the toner image is transferred to the intermediate transfer belt (22) is removed by the cleaning device (12) described above. In this image forming apparatus, the cleaning device (12) has the same configuration as that shown in FIG. In FIG. 2, the tension spring (6) is fixed to one end of the rear half of the arm (3), and the other end of the tension spring (6) is attached to the support (7) fixed in the housing (11). It is fixed. Since it can rotate around the rotation shaft (4) and the arm tends to rotate by the force of the tension spring (6), the blade portion (1) contacts the photoreceptor (14) with a constant force. Yes. For this reason, it is possible to prevent the blade from being squeezed or entangled without excessive frictional force. The auxiliary cleaning device (9) is a fur brush having a driving force, and the transfer residual toner adhering to the surface of the photoreceptor (14) is scraped off by the rubbing force of the auxiliary cleaning device (9). This limits the amount of toner that reaches the tip of the blade portion (1). After that, the spherical toner that has come into contact with the tip of the blade portion (1) starts to rotate and deforms and lifts the cleaning blade to advance in the moving direction of the photosensitive member (14). Then, there is no free length of the blade part (1), and since the auxiliary pressure member (5) is arranged at the rear end part of the blade part (1), the tip of the blade part (1) is densified, Furthermore, because of the high physical properties, the blade portion (1) is not deformed by the rotational force of the toner, and defective cleaning can be prevented. In addition, the cleaning device (12) is a process cartridge, which makes it easy to replace consumables and defective products.
The present invention is not limited to the above-described embodiments, and all design changes within the scope of matters described in the specification are included in the scope of the present invention.

The process cartridge of the present invention integrally supports at least one device selected from an electrostatic image bearing member such as a photosensitive member and a cleaning unit, and a charging device, an exposure device, and a developing device, and is detachably attached to the image forming apparatus main body. The cleaning device is the cleaning device of the present invention.
FIG. 6 shows a schematic configuration example of an image forming apparatus having the process cartridge of the present invention.
In the figure, (101) represents the entire process cartridge, (30) represents a photosensitive member, (31) represents a charging unit, (32) represents a developing unit, and (33) represents a cleaning unit.
In the present invention, a plurality of components such as the cleaning means (33), the photosensitive member (30), the charging means (31), and the developing means (32) are integrally combined as a process cartridge. The process cartridge is configured to be detachable from a main body of an image forming apparatus such as a copying machine or a printer.

  In the image forming apparatus having the process cartridge of the present invention, the photosensitive member is rotationally driven at a predetermined peripheral speed. In the rotation process, the photosensitive member is uniformly charged with a positive or negative predetermined potential on its peripheral surface by the charging unit, and then receives image exposure light from an image exposing unit such as slit exposure or laser beam scanning exposure. An electrostatic latent image is sequentially formed on the peripheral surface of the body, and the formed electrostatic latent image is then developed with toner by a developing unit, and the developed toner image is transferred between the photosensitive member and the transfer unit from the paper feeding unit. Then, the image is sequentially transferred to the transfer material fed in synchronization with the rotation of the photosensitive member by the transfer means. The transfer material that has received the image transfer is separated from the surface of the photosensitive member, introduced into the image fixing means, and fixed on the image, and printed out as a copy (copy). The surface of the photoconductor after the image transfer is cleaned by removing toner remaining after transfer by a cleaning unit, and after being further neutralized, it is repeatedly used for image formation.

It is a schematic sectional drawing of the blade part and arm part of the cleaning apparatus of this invention. It is a schematic sectional drawing which shows an example of the cleaning apparatus of this invention. It is a schematic sectional drawing which shows the other example of the cleaning apparatus of this invention. It is a schematic sectional drawing which shows the other example of the cleaning apparatus of this invention. 1 is a schematic cross-sectional view illustrating an example of an image forming apparatus of the present invention. It is the schematic of the process cartridge of this invention.

Explanation of symbols

1 Blade part 2 First half of arm (Blade support part)
3 Rear half part of arm 4 Rotating shaft part 5 Pressure assisting member 6 Constant force assisting member 7 Supporting part 8 Supporting part 9 Auxiliary cleaning means 10 Waste toner collecting means 11 Housing 12 Cleaning device 13a Magenta unit 13b Cyan unit 13c Yellow unit 13d Black unit 14 Photoconductor 15 Charging device 16 Exposure device 17 Development device 18 Roller 19 Roller 20 Roller 21 Roller 22 Intermediate transfer belt 23 Roller 24 Transfer material 25 Fixing device 30 Photoconductor 31 Charging device 32 Developing device 33 Cleaning device 101 Process cartridge

Claims (9)

A cleaning device that removes toner on the surface of an object to be cleaned with a cleaning blade, wherein the toner is a spheroidized toner in a manufacturing process or a post-manufacturing process, and the cleaning device includes a blade unit that performs cleaning, and an arm The arm part has an arm front half part that supports the blade part, an arm rear half part, and a rotary shaft part that connects the arm front half part and the arm rear half part. There is a stop angle adjustment mechanism that adjusts the angle between the front half of the arm and the rear half of the arm around the shaft, and the rear half of the arm has a constant pressing force against the surface of the object to be cleaned. A constant force applying means for applying a constant force for contact is provided, and the blade portion is fixed to the tip of the front half of the arm, and contacts the surface of the object to be cleaned. That surface as close contact with the surface opposite to the said arm front half, a cleaning device, wherein the distal end of the arm front half portion or protruding from the tip of the cleaning blade, or the absence of the step.   The cleaning device according to claim 1, wherein the front half of the arm has a pressure assisting member for assisting in pressurization at a position in contact with the rear end of the blade.   The cleaning device according to claim 1 or 2, wherein the cleaning blade has a rubber hardness (JIS K6301A) of 70 to 100.   4. The cleaning device according to claim 1, wherein a friction coefficient of the cleaning blade with respect to the surface of the object to be cleaned is 0.5 or less.   The constant force applying means for applying a constant force of the latter half of the arm has a mechanism for applying force to the latter half of the arm from a plurality of directions. A cleaning device according to claim 1. The toner has a circularity represented by the following formula (I) of 1.0 to 1.4 and a flatness represented by the following formula (II) of 1.0 to 1.4. A cleaning device according to any one of claims 1 to 5.
Circularity = {(peripheral length of particle) ² / (projected area of particle)} × (1 / 4π) (I)
Flatness = {(maximum length of particle) ² / (projected area of particle)} × (π / 4) (II)   The cleaning apparatus according to claim 1, wherein the cleaning blade, a cleaning roller, and a cleaning brush are used in combination.   An image carrier for carrying at least a toner image, a charging device for charging the image carrier, an exposure device for forming an electrostatic latent image on the image carrier, and a developing device for forming a toner image on the image carrier. And an image forming apparatus having a transfer device for transferring the toner image formed on the image carrier to the transfer member, and a cleaning device for removing residues on the surface of the image carrier or the intermediate transfer member with a cleaning blade. An electrophotographic image forming apparatus, wherein the cleaning apparatus is the cleaning apparatus according to claim 1.   In a process cartridge that integrally supports at least one device selected from an image carrier and a cleaning device, and a charging device, an exposure device, and a developing device, and is detachable from the image forming apparatus main body, the cleaning device is defined in claims 1 to 3. 8. A process cartridge according to claim 7, wherein the process cartridge is detachable from the image forming apparatus.

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