JP2003149956A - Process cartridge, electrophotographic apparatus, image forming method, and intermediate transfer belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge which is easily maintained, can be miniaturized and made low-cost, stably and accurately carries out density detection measurement for controlling image forming conditions, and provides excellent image corresponding to use conditions, and to provide an electrophotographic apparatus, an image forming method and an intermediate transfer belt. SOLUTION: In the process cartridge, an electrophotographic photoreceptor, the intermediate transfer belt, a primary transfer means and an electric charge applying means are supported integrally. The intermediate transfer belt has an averages glossiness of 30 to 90 obtained in a circumferential direction, a glossiness deviation within 10, an average film thickness of 40 to 200 micrometers, and film thickness unevenness within ±20% relative to the average film thickness. The electrophotographic apparatus is provided with the process cartridge. The intermediate transfer belt is for the process cartridge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process cartridge, an electrophotographic apparatus, an image forming method and an intermediate transfer belt.

[0002]

2. Description of the Related Art An electrophotographic image forming apparatus (electrophotographic apparatus) using an intermediate transfer belt is used to sequentially transfer a plurality of component color images of full color image information and multicolor image information in a layered manner to obtain a full color image or a multicolor image. It is effective as a full-color electrophotographic device or a multi-color image forming device that outputs an image-formed product obtained by combining and reproducing images.

A full-color electrophotographic apparatus using an intermediate transfer belt has an electrophotographic apparatus for pasting or adsorbing a second image bearing member on a conventional transfer drum and transferring an image from the electrophotographic photosensitive member thereto. Compared with a transfer device of a full-color electrophotographic device (for example, described in JP-A-63-301960), an image can be transferred from the intermediate transfer belt without any processing or control of the transfer material. From thin paper (40 g / m ² paper) to thick paper (20 g
0 g / m ² paper), regardless of the width and width,
There is an advantage that a wide variety of second image carriers can be selected.

Further, by adopting an intermediate transfer belt shape,
Compared with the case where a rigid cylinder such as an intermediate transfer drum is used, the degree of freedom in arranging inside the electrophotographic apparatus is increased, and the apparatus main body can be downsized and the cost can be reduced by effectively utilizing the space. There are also merits.

However, the life of the intermediate transfer belt is shorter than that of the main body, and replacement is essential under the present circumstances.

Further, it is necessary to install and treat a waste toner container in which the developer (hereinafter, toner) remaining on the intermediate transfer belt is collected.

In addition to these, in printers and copying machines, it is necessary to replace many parts such as the electrophotographic photosensitive member, the developing means, and the toner.

As a method of unitizing these replacement parts and easily attaching and detaching them from the main body, Japanese Patent Laid-Open No. 8-137181
In the publication, it is proposed that the intermediate transfer belt and the electrophotographic photosensitive member are arranged as independent units so as to be easily detachable from the main body.

However, with this means, the number of replacement units is large and the user's operation becomes complicated. Further, since each unit is designed and arranged independently of each other, problems such as an increase in size of the main body and an increase in cost occur.

As a means for solving this problem, a means for simultaneously removing and replacing the intermediate transfer belt, which is a replacement part, and the electrophotographic photosensitive member as an integrated unit from the main body, and replacing the same is disclosed in JP-A-6-110261. JP-A-10-1
It is proposed in Japanese Patent No. 77329 and Japanese Patent Laid-Open No. 11-30944.

[0011]

However, the intermediate transfer belt and the electrophotographic photosensitive member are constituted as an integrated unit, that is, the intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge (hereinafter, also simply referred to as "integrated process cartridge"). In the method (1), when a problem occurs in the intermediate transfer belt, the whole process cartridge must be replaced, which may increase the cost.

Generally, in a full-color electrophotographic apparatus, the image density varies or the proper color tone cannot be obtained due to changes in the environment in which it is used.

Therefore, in the case of a full-color electrophotographic apparatus using an intermediate transfer belt, as a means for obtaining accurate density information, toner images (patches) for density detection of each color formed on the intermediate transfer belt are Illuminate with a predetermined light,
It has a density detecting means for detecting the density from the reflected light and the reflectance of the intermediate transfer belt, and feeding back the detection result to the exposure amount, the developing bias and the like to control the image density. Therefore, it is important that the glossiness of the surface of the intermediate transfer belt is stable over the entire circumference of the belt.

However, when the integrated process cartridge is shipped or when the user removes the integrated process cartridge and carries it, since the intermediate transfer belt and the electrophotographic photosensitive member are in contact with each other, the intermediate transfer belt and the electrophotographic photosensitive member vibrate. Or they are subject to mutual friction or sliding frequently and repeatedly. Therefore, the surface of the intermediate transfer belt is scratched and scraped, and the glossiness of the intermediate transfer belt at the contact portion is reduced.

Further, by storing the integrated process cartridge for a long time at the time of shipping, the components constituting the intermediate transfer belt and the electrophotographic photosensitive member exude, the abutting portion becomes cloudy, and the glossiness decreases.

Further, as the number of prints increases, dirt on the surface of the intermediate transfer belt accumulates due to toner or paper dust, or minute scratches occur, so that the glossiness of the intermediate transfer belt decreases.

Further, in the intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge, since the intermediate transfer belt is always in contact with the electrophotographic photosensitive member, friction between the intermediate transfer belt and the electrophotographic photosensitive member causes an intermediate transfer. Not only does the gloss of the belt surface decrease overall, but also uneven gloss occurs. As a result, density detection is not accurately performed, and density unevenness occurs for each image. Further, the unevenness of the glossiness from the initial stage of use is magnified as the belt is used, and the unevenness of the density of each image is further deteriorated.

On the other hand, in an electrophotographic apparatus in which the intermediate transfer belt and the electrophotographic photosensitive member are independent units,
Even if a belt with uneven gloss is used, the unevenness hardly changes.

The object of the present invention is to facilitate maintenance,
An intermediate transfer belt that enables downsizing of the device and cost reduction, can perform more stable and more accurate density detection measurement for controlling image forming conditions, and can obtain excellent images according to use conditions. -To provide an electrophotographic photosensitive member integrated process cartridge, an electrophotographic apparatus having the process cartridge, an image forming method using the electrophotographic apparatus, and an intermediate transfer belt for the process cartridge.

[0020]

In order to solve the above problems, the inventors of the present invention have made earnest studies and found that the average glossiness of the intermediate transfer belt is 30 to 90 and the deviation thereof is preferably 10 or less. I found it.

Further, since the intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge is often in a stationary state under tension for a long time before being actually used, it is not possible to use the tensioned roller. A bending tendency is given to the portion, and if the density detection is performed at this portion, accurate reflected light cannot be obtained, and as a result, unevenness in the density occurs for each image.

In order to solve the above-mentioned problems, the present inventors have made earnest studies and found that the average film thickness of the intermediate transfer belt is 40 μm.
It was found that it is preferable that the thickness is m to 200 μm and the unevenness is within ± 20% of the average value.

That is, the present invention is a process cartridge which is detachably mountable to the main body of an electrophotographic apparatus and has an electrophotographic photosensitive member for carrying a toner image and an abutting portion for contacting the electrophotographic photosensitive member. An intermediate transfer belt, a primary transfer means for primarily transferring an image of the toner from the electrophotographic photosensitive member to the intermediate transfer belt at the contact portion, and toner on the intermediate transfer belt at the contact portion. In order to return the toner to the electrophotographic photosensitive member and clean the intermediate transfer belt, a charge applying unit for applying a charge having a polarity opposite to the polarity of the toner at the time of the primary transfer to the toner on the intermediate transfer belt is integrated. The average glossiness obtained in the circumferential direction of the intermediate transfer belt is 30 to 90, the deviation of the glossiness is 10 or less, and the average film thickness of the intermediate transfer belt is 40.
The process cartridge is characterized in that the film thickness unevenness of the intermediate transfer belt is within ± 20% of the average film thickness.

In the present invention, the electrophotographic photoreceptor for carrying the toner image, the charging means for charging the electrophotographic photoreceptor, and the electrophotographic photoreceptor charged by the charging means are statically charged. An exposure unit for forming an electro-latent image, and a developing unit for developing the electrostatic latent image of the electrophotographic photosensitive member formed by the exposure unit with toner to form a toner image on the electrophotographic photosensitive member. An intermediate transfer belt having a contact portion with the electrophotographic photosensitive member for secondarily transferring the toner image transferred after the primary transfer of the toner image from the electrophotographic photosensitive member, A primary transfer means for primarily transferring an image of the toner from the electrophotographic photosensitive member to the intermediate transfer belt at the corresponding contact portion, and toner on the intermediate transfer belt at the corresponding contact portion Return to the intermediate transfer belt To clean, and a charge applying unit for applying a polarity opposite the polarity of the charge of the toner during the primary transfer to the toner on the intermediate transfer belt,
At least the electrophotographic photosensitive member, the intermediate transfer belt,
Integrally supporting the primary transfer means and the charge applying means,
The electrophotographic apparatus main body has a detachable process cartridge, the average glossiness obtained in the circumferential direction of the intermediate transfer belt is 30 to 90, and the glossiness deviation is 1
0 or less, and the average film thickness of the intermediate transfer belt is 40 to 2
The electrophotographic apparatus is characterized in that the thickness of the intermediate transfer belt is not more than ± 20% with respect to the average film thickness.

Further, the present invention is formed by a charging step of charging the electrophotographic photosensitive member, an exposure step of forming an electrostatic latent image on the electrophotographic photosensitive member charged in the charging step, and the exposure step. The electrostatic latent image on the electrophotographic photoreceptor is developed with toner,
A developing step for forming a toner image on the electrophotographic photoreceptor,
A primary transfer step in which the image of the toner formed in the developing step is primarily transferred by a primary transfer means from the electrophotographic photosensitive member to an intermediate transfer belt having a contact portion with the electrophotographic photosensitive member; A secondary transfer step of secondarily transferring the image of the toner primarily transferred in the transfer step onto a transfer material, and a polarity opposite to the polarity of the toner at the primary transfer step in the toner on the intermediate transfer belt by the charge applying means. Image formation including an electric charge applying step of applying a polar electric charge, and an intermediate transfer belt cleaning step of returning the toner on the intermediate transfer belt to the electrophotographic photoreceptor at a contact portion to clean the intermediate transfer belt. A method of supporting at least the electrophotographic photosensitive member, the intermediate transfer belt, the primary transfer unit, and the charge applying unit, and is detachable from the main body of the electrophotographic apparatus. An image forming method using the electrophotographic apparatus having the cartridges, average gloss obtained with respect to the circumferential direction of the intermediate transfer belt 30 to 90,
The deviation of the glossiness is 10 or less, the average film thickness of the intermediate transfer belt is 40 to 200 μm, and the film thickness unevenness of the intermediate transfer belt is within ± 20% of the average film thickness. This is a characteristic image forming method.

The present invention is also an intermediate transfer belt for the above process cartridge.

It should be noted that Japanese Patent Laid-Open No. 10-63111 discloses a method for reducing the change in glossiness of intermediate transfer, and only describes the average glossiness of the intermediate transfer belt. No mention is made of the thickness of the intermediate transfer belt and its unevenness.

Further, in Japanese Patent Laid-Open No. 5-31818,
A method of making a belt having a uniform surface is disclosed. No mention is made of the thickness of the intermediate transfer belt and its unevenness.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below.

In the present invention, as a result of studying simplification of maintenance, downsizing of main body and process cartridge, cost reduction, and improvement of image quality, after using the intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge,
The initial goal was achieved by combining several measures.

First, in order to reduce the size of the process cartridge and reduce the cost, the cleaning method for the intermediate transfer belt is the simultaneous primary transfer cleaning method in which the transfer residual toner is charged to the opposite polarity and returned to the electrophotographic photosensitive member at the same time during the primary transfer. Has been adopted.

Specifically, a voltage is applied to a charge applying means (for example, a roller shape) arranged on the intermediate transfer belt so as to be separable and contactable, so that the secondary transfer residual toner is charged with a charge having a polarity opposite to that at the time of primary transfer. This is a method of applying and then returning to the electrophotographic photosensitive member by a primary transfer electric field in a temporary transfer portion.

The toner returned to the electrophotographic photosensitive member from the intermediate transfer belt is preferably removed by a cleaning mechanism such as a cleaning blade for the electrophotographic photosensitive member.

According to this method, cleaning blades are arranged on both the electrophotographic photosensitive member and the intermediate transfer belt,
Compared with a system in which a waste toner feeding mechanism and a container are installed, the process cartridge has a great effect in downsizing and cost reduction.

As the intermediate transfer belt capable of more stably and more accurately measuring the density for controlling the image forming conditions and obtaining the most excellent image according to the use conditions, the gloss of the belt surface is measured. The average degree is 30 to 90, 40 to 85 is more preferable, and 40 to 70 is even more preferable. If the average glossiness is less than 30, the intensity of reflected light from the intermediate transfer belt cannot be obtained and accurate density detection cannot be performed. Further, when the glossiness exceeds 90, the gloss of the contact portion with the electrophotographic photosensitive member is significantly reduced during shipping and storage of the integrated process cartridge. In addition, the surface condition of the belt is abruptly roughened as it is printed, and the glossiness is greatly reduced. Therefore, accurate density detection cannot be performed.

The deviation in glossiness must be within 10, preferably within 9 and more preferably within 5. If the deviation of the glossiness is larger than 10, the unevenness of the reflected light becomes large, and the density detection result varies, resulting in the unevenness of the density for each image. In addition, the intermediate transfer belt having uneven gloss, etc., is greatly reduced in gloss at the contact portion with the electrophotographic photosensitive member at the time of shipping or storage thereof, so that the unevenness is enlarged or as the printing is repeated, The unevenness is magnified and the uneven density of each image is further deteriorated.

The film thickness of the intermediate transfer belt used in the process cartridge of the present invention is 40 to 200 μm and 50
To 150 μm, preferably 60 to 140 μm
Is more preferable. If the film thickness exceeds 200 μm, a bending tendency is imparted to the stretched roller portion, and if density detection is performed at this portion, accurate reflected light cannot be obtained, and as a result, density unevenness may occur for each image. Occurs. Further, if the film thickness is less than 40 μm, the durability strength is insufficient,
Belt breaks and cracks occur.

The film thickness unevenness is ± 20% with respect to the average value.
It must be within the range, more preferably within ± 12%, and even more preferably within ± 10%. If the film thickness unevenness is larger than ± 20%, a bending tendency is given to the thick film portion, and the density detection cannot be performed accurately in this portion.

The measurement conditions were as follows.

<Glossiness Measurement Method> The glossiness of the intermediate transfer belt used in the process cartridge of the present invention was measured by using a handy gloss meter IG-320 manufactured by Horiba Ltd.
It is a value obtained by measuring the center of the belt at equal intervals in the circumferential direction over the entire circumference of 20 points and averaging.

The deviation of glossiness is a value obtained by subtracting the minimum value from the maximum value.

<Film Thickness Measuring Method> The minimum thickness of the intermediate transfer belt used in the process cartridge of the present invention is 1 μm.
A dial gauge of m is a value obtained by measuring and averaging over 20 points at equal intervals in the circumferential direction in the center of the belt.

At the time of primary transfer, the pressing force of the intermediate transfer belt against the electrophotographic photosensitive member is preferably 1N to 50N, 5
N-20N is more preferable. If the pressing pressure exceeds 50 N, the friction between the intermediate transfer belt and the electrophotographic photosensitive member may increase, and scratches may occur.
It causes uneven gloss. If the pressing force is less than 1N, the primary transfer is not performed well, which may cause an image defect.

Of the molding raw materials used for the intermediate transfer belt used in the process cartridge of the present invention, the resin which is the main material is not particularly limited as long as it satisfies the characteristics of the present invention. For example, polyethylene or polypropylene. Olefin resin and polystyrene resin, acrylic resin, polyester resin, polycarbonate, sulfur-containing resin such as polysulfone and polyether sulfone and polyphenylene sulfide, fluorine-containing resin such as polyvinylidene fluoride and polyethylene-tetrafluoroethylene copolymer, Polyurethane resin, silicone resin, ketone resin, polyvinylidene chloride, thermoplastic polyimide resin, polyamide resin, modified polyphenylene oxide resin, etc., and one or two of these various modified resins or copolymers.
More than one type can be used. However, the present invention is not limited to the above materials.

Next, the additive mixed for adjusting the electric resistance value of the intermediate transfer belt used in the process cartridge of the present invention is not particularly limited, but as an electrically conductive filler for adjusting the resistance, There are carbon black and various conductive metal oxides. As non-filler resistance modifiers, low molecular weight ionic conductive materials such as various metal salts and glycols, and antistatic agents containing ether bonds and hydroxyl groups in the molecule. Examples thereof include resins and organic polymer compounds having electronic conductivity.

What is needed here is the dispersed state of each additive and the components that make up the intermediate transfer belt, such as the resin, and the effect of the present invention can be obtained if particle aggregation or extreme separation of some components occurs. Hard to get. The choice of materials and means of dispersion is important.

As a method of molding the intermediate transfer belt, it is preferable to use a manufacturing method capable of manufacturing a seamless belt and having high manufacturing efficiency and cost reduction.

As a means for this, there is a method of continuously extruding from a circular die and then cutting it into a required length to produce a belt. For example, inflation molding is suitable.

One embodiment of the method of manufacturing the intermediate transfer belt of the present invention will be described below. However, the present invention is not limited thereto.

FIG. 4 shows a schematic structure of the molding apparatus for the intermediate transfer belt of the present invention. This device is basically an extruder,
It has an extrusion die and a gas blowing device.

First, a molding resin, a conductive agent, an additive and the like are premixed in accordance with a desired formulation, and the kneading-dispersed molding raw material is put into a hopper 102 provided in the extruder 100.

In the extruder 100, the raw material for molding has a melt viscosity that enables belt molding in the subsequent step, and
The set temperature and the screw configuration of the extruder are selected so that the raw materials are evenly dispersed.

The raw material for molding is melted and kneaded in the extruder 100 to form a melt, and the melt enters the annular die 103.

The annular die 103 is provided with a gas introduction passage 104, and air is blown into the center of the annular die 103 from the gas introduction passage 104, so that the molten material passing through the die 103 expands in the radial direction. It expands and becomes the tubular film 110.

At this time, as the gas to be blown, nitrogen, carbon dioxide, argon or the like can be selected in addition to air. The expanded compact is pulled upward while being cooled by the external cooling ring 105.

Generally, in the inflation device, the tube is crushed from the left and right by the stabilizer 106, folded into a sheet, and pinched by the pinch roller 107 so as not to let air out of the tube, and pulled at a constant speed.

Next, the taken film is cut by the cutting device 108 to obtain a tubular film having a desired size.

Next, the tubular film is processed using a mold for the purpose of adjusting the surface smoothness and dimensions and removing the crease formed on the film during molding.

Specifically, there is a method of using a set of cylindrical molds made of materials having different thermal expansion coefficients and having different diameters.

The coefficient of thermal expansion of the small-diameter cylindrical mold (inner mold 201) is made larger than that of the large-diameter cylindrical mold (outer mold 202), and the tubular film 160 molded into this inner mold.
Then, the inner die is inserted into the outer die so that the tubular film is sandwiched between the inner die and the outer die (FIG. 9).

The gap between the molds is calculated by the difference between the heating temperature and the coefficient of thermal expansion between the inner mold and the outer mold and the required pressure.

Inner mold 201, tubular film 160, outer mold 2
The molds set in the order of 00 are heated to near the softening point temperature of the resin of the tubular film. The inner mold 201 having a large coefficient of thermal expansion expands from the outer mold 200 by heating, and the tubular film 1
60 Even pressure is applied to the entire surface. At this time, the surface of the tubular film 160 that has reached the vicinity of the softening point is pressed against the inner surface of the outer die that has been processed to be smooth, and the smoothness of the surface of the tubular film 160 is improved.

Then, by cooling and removing the tubular film 160 from the mold, a smooth surface property can be obtained.

After that, a reinforcing member, a guide member, and a position detecting member are attached and precision cut as required to manufacture an intermediate transfer belt.

Next, the density detecting sensor 14 as the density detecting means will be briefly described with reference to FIG.

The density detection sensor 14 is formed on the electrophotographic photosensitive member by controlling the charging means, the developing means, etc. as the process means, and is further subjected to a predetermined test transferred from the electrophotographic photosensitive body to the intermediate transfer belt 5. A pattern image (a resist detection pattern or a density detection pattern) is detected.

As shown in FIG. 3, the density detection sensor 14
Has a light emitting element 141 such as an LED and a light receiving element 142 such as a photodiode.

The irradiation light from the light emitting element 141 is incident on the intermediate transfer belt 5 at an angle α and is reflected at the detection position 143. The light receiving element 142 is provided at a position for detecting the specular reflection component of the irradiation light.

The amount of light reflected at the detection position 143 is determined by the reflectance of the intermediate transfer belt 5 as a base and the toner amount of the density patch 16 which is a test pattern image. As the toner amount of the density patch 16 increases, the surface of the intermediate transfer belt 5 that is the base is hidden by that much, and the output from the sensor decreases.

Although the density detection sensor 14 of the type that detects specular reflection light is used in FIG. 3, the present invention is not limited to this. For example, a sensor of the type that detects diffused light may also be used. Good.

FIG. 1 shows an example of an electrophotographic apparatus using the intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge of the present invention.

FIG. 1 shows a full-color electrophotographic apparatus (copier or laser beam printer).

Reference numeral 1 denotes a rotary drum type electrophotographic photosensitive member which is repeatedly used as a first image bearing member, and is rotationally driven at a predetermined peripheral speed (process speed) in a direction indicated by an arrow.

The electrophotographic photosensitive member 1 is uniformly charged to a predetermined polarity and potential by the primary charging means 2 during the rotation process. The power source 32 of the primary charging means applies an alternating current on a direct current, but may apply only a direct current.

Next, exposure means (not shown) (a color separation / imaging exposure optical system for a color original image, a scanning exposure by a laser scanner which outputs a laser beam modulated corresponding to a time series electric digital pixel signal of image information) By receiving the exposure light 3 from the system, an electrostatic latent image corresponding to the first color component image (for example, yellow color component image) of the target full-color image is formed.

Then, the electrostatic latent image is developed by the first developing means (yellow developing means 41) with the yellow toner Y which is the first color. At this time, second to fourth
Of the developing means (magenta developing means 42, cyan developing means 43, and black developing means 44) are in the operation-off state, do not act on the electrophotographic photoreceptor 1, and The yellow toner image of the color is
Not affected by the fourth developing means.

The intermediate transfer belt 5 is rotationally driven in the arrow direction at a predetermined peripheral speed (process speed).

While the first color yellow toner image formed and carried on the electrophotographic photosensitive member 1 passes through the contact portion between the electrophotographic photosensitive member 1 and the intermediate transfer belt 5, the primary transfer means 6 The primary transfer is sequentially performed on the outer peripheral surface of the intermediate transfer belt 5 by the electric field formed by the primary transfer bias applied to the intermediate transfer belt 5.

The surface of the electrophotographic photosensitive member 1 on which the transfer of the yellow toner image of the first color corresponding to the intermediate transfer belt 5 has been completed is cleaned by the electrophotographic photosensitive member cleaning means 13.

Similarly, the magenta toner image of the second color, the cyan toner image of the third color, and the black toner image of the fourth color are sequentially transferred onto the intermediate transfer belt 5 in a superimposed manner to correspond to the target full-color image. The combined color toner image is formed.

The primary transfer bias for sequentially superposing and transferring the toner images of the first to fourth colors from the electrophotographic photosensitive member 1 to the intermediate transfer belt 5 is applied from the bias power source 30 with the polarity (+) opposite to that of the toner. To be done. The applied voltage is, for example, +1
It is in the range of 00V to 2kV.

Reference numeral 7 denotes a secondary transfer means (secondary transfer roller).
Is arranged in parallel with the secondary transfer counter roller 8 so as to be supported by the lower surface of the intermediate transfer belt 5 so as to be separable from the electrophotographic photosensitive member 1 to the intermediate transfer belt 5.
In the primary transfer process of the toner image of the third color, the secondary transfer means 7 can be separated from the intermediate transfer belt 5.

The transfer of the composite color toner image transferred onto the intermediate transfer belt 5 onto the transfer material P, which is the second image carrier, is performed by the secondary transfer means 7 contacting the intermediate transfer belt 5. The transfer material P is fed from the paper feed roller 11 through the transfer material guide 10 to the contact portion between the intermediate transfer belt 5 and the secondary transfer means 7 at a predetermined timing, and the secondary transfer bias is supplied from the power supply 31 to the secondary transfer bias. It is applied to the next transfer means 7. By this secondary transfer bias, the composite color toner image is secondarily transferred from the intermediate transfer belt 5 to the transfer material P which is the second image carrier.

The transfer material P having the toner image transferred thereto is introduced into the fixing means 15 and is heat-fixed.

After the transfer of the image to the transfer material P is completed, the intermediate transfer belt 5 is contacted with the charge applying means 9 arranged so as to be separable from the intermediate transfer belt 5, and a bias having a polarity opposite to that of the electrophotographic photosensitive member 1 is applied. As a result, the transfer residual toner that has not been transferred to the transfer material P and remains on the intermediate transfer belt 5 is given a charge of the opposite polarity to that at the time of primary transfer. The bias power source 33 superimposes alternating current on direct current and applies it.

The transfer residual toner charged to the opposite polarity to that at the time of the primary transfer is electrostatically transferred to the electrophotographic photosensitive member 1 at the contact portion with the electrophotographic photosensitive member 1 and in the vicinity thereof, so that the intermediate toner is transferred. The transfer body is cleaned. Since this step can be performed at the same time as the primary transfer, there is no reduction in throughput.

Next, the intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge of the present invention will be described.

As shown in FIG. 2, the process cartridge of the present invention comprises at least the intermediate transfer belt 5, the electrophotographic photosensitive member 1 and the charge giving means 9 as a unit, preferably the electrophotographic photosensitive member cleaning means 13. Is also configured as an integral unit so that it can be easily attached to and detached from the main body of the electrophotographic apparatus.

The cleaning of the intermediate transfer belt of the present invention is a mechanism necessary for charging the transfer residual toner to the polarity opposite to that of the primary transfer and returning it to the electrophotographic photosensitive member at the primary transfer portion as described above. In the figure, a charge applying means 9 made of an elastic body of medium resistance is provided.

In this figure, cleaning of the electrophotographic photosensitive member is blade cleaning. If the waste toner container (not shown) is also integrated, the transfer residual toner of both the intermediate transfer belt and the electrophotographic photosensitive member is discarded at the same time when the process cartridge is replaced, which can contribute to improvement of maintainability.

If the intermediate transfer belt is stretched by two rollers 8 and 12, the number of parts can be reduced and the size can be reduced.

In the figure, 8 is a driving roller and at the same time an opposing roller of a roller-shaped charge applying means.

The tension roller 12 which is rotated by following the intermediate transfer belt has a mechanism for sliding,
It is pressed against the direction of the arrow by a compression spring to give tension to the intermediate transfer belt. The slide width is preferably 1 to 5 mm, and the total pressure of the springs is preferably 5 to 100N.

Further, the electrophotographic photosensitive member 1 and the driving roller 8
Has a coupling (not shown), and the rotational driving force is transmitted from the main body.

FIG. 5 shows a schematic structure of a process cartridge constituted by connecting an electrophotographic photosensitive member unit having an electrophotographic photosensitive member and an intermediate transfer belt unit having an intermediate transfer belt.

Further, FIGS. 6 and 7 show schematic structures of an intermediate transfer belt unit and an electrophotographic photosensitive member unit, respectively.

The frame structure is roughly divided into two.

The electrophotographic photosensitive member frame 59, which is integrally formed with the waste toner container 52 shown in FIG. 7, has the electrophotographic photosensitive member 1, the charging roller 2, the cleaning blade 53, the screw 54, and the drum shutter 55 as main components. The electrophotographic photosensitive member unit 50 and the intermediary transfer belt frame 45 shown in FIG. 6 have the intermediary transfer belt 5 suspended by the drive roller 8 and the driven roller 12 (suspended by the drive roller 8). A primary transfer roller 5 is provided on the inner side of the intermediate transfer belt facing the photographic photoreceptor 1.
8, the drive roller 8 is divided into an intermediate transfer belt unit 51 in which a charge applying unit (intermediate transfer belt cleaning roller) 9 is also arranged.

In these two units, the projections 71 provided on the left and right ends of the electrophotographic photosensitive member frame 59 are inserted into the positioning holes 72 provided in the intermediate transfer belt frame 45, respectively, while the electrophotographic photosensitive member frame 59 is inserted. Frame 59
The claw 73 of the snap-fit type hook provided at the center of the width direction of the
Are fitted and connected.

Here, the positioning hole 72 and the lock hole 74 provided in the intermediate transfer frame 45 are larger than the protrusion 71 and the hook claw 73 provided in the electrophotographic photosensitive member frame 59 by a predetermined amount. The electrophotographic photosensitive member unit 50 and the intermediate transfer belt unit 51 are opened.
Between them, a predetermined amount of relative position movement is possible.

The positioning hole 72 has a taper portion 72a.
Is provided for easy attachment and detachment.

In FIG. 7, the electrophotographic photosensitive member unit 5
Press the hook claw 73 of 0 to press the intermediate transfer belt unit 51.
From the lock hole 74 of the electrophotographic photoreceptor unit 50.
When rotated, the electrophotographic photosensitive member unit and the intermediate transfer belt unit can be divided as shown in FIGS.

At the time of connection, contrary to the above, the projection 71 of the electrophotographic photosensitive member unit 50 is inserted into the positioning hole 72 of the intermediate transfer belt unit 51, and is rotated in the opposite direction to that at the time of removal to hook. The two units are connected by pushing the claw 73 into the lock hole 74.

FIG. 8 shows how the process cartridge of the present invention is attached to and detached from the electrophotographic apparatus.

Just by opening the upper lid 60 of the main body of the electrophotographic apparatus, the process cartridge can be attached / detached as easily as the conventional black and white laser beam printer, and maintenance such as jam processing and process cartridge replacement can be easily performed.

[0106]

EXAMPLES The present invention will be described in more detail below with reference to examples. In addition, "part" in an Example means a mass part.

(Example 1) Vinylidene fluoride resin (PVDF) 100 parts Polyether ester amide (polyether-containing antistatic resin: Pelestat NC6321 manufactured by Sanyo Kasei Co., Ltd.) 15 parts Biaxial extrusion of these materials Each material was mixed by melt-kneading at 210 ° C. in a machine and extruded with a strand having a diameter of about 2 mm to cut into pellets.

This was used as molding raw material 1.

Next, in the molding apparatus shown in FIG. 4, the molding die was a single-layer annular die having a die slit diameter of 100 mm. Die slit is 0.8m
m.

The molding raw material 1 which had been sufficiently heated and dried was charged into the material hopper 102 of this molding apparatus, heated and melted, and extruded into a cylindrical shape at 210 ° C. from the die.

An external cooling ring 105 was installed around the die, and the extruded film was cooled by blowing air from the surroundings.

Further, air was blown into the extruded tubular film from the gas introduction passage 104 to have a diameter of 140 m.
After expanding and expanding to m, it was continuously taken up by a take-up device at a constant speed.

The introduction of air was stopped when the diameter reached the desired value.

Further, the tubular film was cut by the cutting device 108 following the pinch roller.

After stabilizing the thickness to 100 μm, the length 31
A tubular film 1 was formed by cutting at 0 mm.

The tubular film 1 was subjected to size and surface smoothness adjustment and fold removal by using a set of cylindrical molds made of metals having different thermal expansion coefficients.

An aluminum material having a high coefficient of thermal expansion was used for the inner mold, and stainless steel having a coefficient of thermal expansion lower than that of aluminum was used for the outer mold. The outer mold used was one whose inner surface was buffed to give a mirror finish. The dimensional gap between the outer diameter of the inner mold and the inner diameter of the outer mold was 170 μm.

An inner mold having a high coefficient of thermal expansion is covered with the cylindrical film 1, and the inner mold is inserted into an outer mold having a smooth inner surface (surface roughness Ra = 0.048 μm) and the temperature is 170 ° C. for 20 minutes. Heated.

After cooling, the intermediate transfer belt (1) having a diameter of 140 mm was prepared by removing it from the cylinder, cutting the end, and attaching a meandering prevention member.

When the glossiness was measured according to the measuring method of the present invention, the average glossiness was 70.0,
The deviation in glossiness was 5.0. Further, when the film thickness was measured, the average film thickness was 101.3 μm, and the film thickness unevenness was ± 9.6%.

This intermediate transfer belt (1) was incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer was set to 15N. did.

This process cartridge was set in the electrophotographic apparatus shown in FIG. 1, and a print test of a full-color image was conducted on 80 g / m ² paper.

The exposure apparatus used at this time is 600 dp.
i digital laser system.

Further, this electrophotographic apparatus has a density detecting sensor shown in FIG.

When the initial image was visually evaluated, the density was detected without any problem, and there was no density unevenness for each image.
A good full-color image was obtained.

Continuously, a durability print test of 10,000 sheets was continuously performed at a speed of 4 sheets per minute, and the images were evaluated in the same manner. As a result, a good full-color image having no density unevenness for each image was obtained as in the initial stage. Was obtained.

A process cartridge was prepared in the same manner as above, left for 1 month in an environment of 23 ° C./55% RH, and then subjected to a print test. As a result, a good full-color image with no density unevenness for each image was obtained. An image was obtained.

The images are evaluated as follows. A: Very good B: Good C: Not good C determined that the effect of the present invention was not obtained.

Example 2 Except that an outer mold (surface roughness Ra = 0.098 μm) having an inner surface blasted was used,
An intermediate transfer belt (2) was produced in the same manner as in Example 1.

The average glossiness was 40.6 and the glossiness deviation was 5.0.

The average film thickness is 101.2 μm,
The unevenness of the film thickness was ± 8.8%.

This intermediate transfer belt (2) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, a good full-color image was obtained without any density unevenness in each image at the initial stage after 10,000 sheets were run and after left for 1 month.

Example 3 Except that an outer mold (surface roughness Ra = 0.123 μm) whose inner surface was blasted was used,
An intermediate transfer belt (3) was produced in the same manner as in Example 1.

The average glossiness was 35.0, and the deviation of glossiness was 4.8. The average film thickness is 100.3μ
m, and the unevenness of the film thickness was ± 8.9%.

This intermediate transfer belt (3) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And When the image evaluation was performed in the same manner as in Example 1, density unevenness occurred in each image in the initial stage, but it was not a problem.

Also, after 10,000 sheets of durability, it was about the same as the initial stage even after being left for one month.

Example 4 Polycarbonate A 100 parts Polyether ester amide (polyether-containing antistatic resin: Pelestat NC6321: manufactured by Sanyo Kasei Co., Ltd.) 15 parts The same as Example 1 except that the above materials were used. Then, an intermediate transfer belt (4) was produced.

The average glossiness was 87.2, and the deviation of glossiness was 5.0. The average film thickness is 101.3μ.
m, and the unevenness of the film thickness was ± 9.5%.

This intermediate transfer belt (4) was incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer was 15N. And

When the initial image evaluation was performed in the same manner as in Example 1, a good full-color image was obtained without unevenness in the density of each image.

After running 10,000 sheets, uneven density occurred, but it was not a problem.

The same was true after leaving for 1 month.

(Example 5) An intermediate transfer belt (5) was produced in the same manner as in Example 1 except that the inner diameter of the outer mold was changed to make the gap between the inner mold and the outer mold 180 μm.

Then, since the cylindrical film covered with the inner mold was not completely adhered to the outer mold during heating, uneven glossiness was generated on the surface of the film.

The average glossiness was 69.8, and the glossiness deviation was 9.6.

The average film thickness is 100.8 μm,
The unevenness of the film thickness was ± 8.9%.

This intermediate transfer belt (5) is incorporated in an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

When image evaluation was performed in the same manner as in Example 1, unevenness in the density of each image occurred in the initial stage, but it was not a problem.

Also, after 10,000 sheets of durability, it was about the same as the initial stage even after being left for one month.

Example 6 An intermediate transfer belt was prepared in the same manner as in Example 1 except that a cylindrical film having a thickness of 145 μm was used and the inner mold was changed in inner diameter to make the gap between the inner mold and the outer mold 200 μm. (6) was produced.

The average glossiness was 69.6 and the glossiness deviation was 4.4.

The average film thickness is 144.6 μm,
The unevenness of the film thickness was ± 8.6%.

This intermediate transfer belt (6) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, a good full-color image was obtained without causing unevenness in density for each image at the initial stage and after 10,000 sheets had been run.

After being left for 1 month, some unevenness in density occurred, but it was not a problem.

Example 7 An intermediate transfer was carried out in the same manner as in Example 1 except that a cylindrical film having a film thickness of 52 μm was used and the inner mold was changed in inner diameter to make the gap between the inner mold and the outer mold 125 μm. A belt (7) was produced.

The average glossiness was 68.8 and the deviation of glossiness was 4.7.

The average film thickness was 52.1 μm, and the film thickness unevenness was ± 9.9%.

This intermediate transfer belt (7) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, a good full-color image was obtained without unevenness in the density of each image at the initial stage after 10,000 sheets had been run.

After leaving for 1 month, the density was somewhat uneven, but it was not a problem.

(Example 8) An intermediate transfer belt (8) was produced in the same manner as in Example 1 except that the temperature at which a tubular film was produced by extrusion molding was 190 ° C.

The average glossiness was 69.3, and the deviation of glossiness was 4.8.

The average film thickness is 102.2 μm,
The unevenness of the film thickness was ± 20.0%.

This intermediate transfer belt (8) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, a good full-color image was obtained without causing unevenness in density for each image at the initial stage and after running 10,000 sheets.

After being left for one month, uneven density occurred, but it was not a problem.

(Example 9) An intermediate transfer belt (9) was prepared in the same manner as in Example 1.

The average glossiness was 69.7, and the deviation of glossiness was 4.7.

The average film thickness is 100.0 μm,
The unevenness of the film thickness was ± 9.3%.

This intermediate transfer belt (9) was incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer was 50N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, density unevenness did not occur for each image in the initial stage, after 10,000 sheets were run, and after left for 1 month.

(Example 10) An intermediate transfer belt (10) was produced in the same manner as in Example 1.

The average glossiness was 68.5, and the glossiness deviation was 4.9.

The average film thickness is 100.5 μm,
The unevenness of the film thickness was ± 9.5%.

This intermediate transfer belt (10) is incorporated in an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 60N. And

When image evaluation was performed in the same manner as in Example 1, unevenness in the density of each image occurred in the initial stage, but it was not a problem.

Also, after 10,000 sheets of durability, it was about the same as the initial stage even after being left for one month.

(Example 11) An intermediate transfer belt (11) was produced in the same manner as in Example 1.

The average glossiness was 68.4 and the glossiness deviation was 4.8.

The average film thickness was 99.6 μm and the film thickness unevenness was ± 9.5%.

This intermediate transfer belt (11) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 1N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, density unevenness did not occur for each image in the initial stage, after 10,000 sheets of durability, and after leaving for 1 month.

(Example 12) An intermediate transfer belt (12) was produced in the same manner as in Example 1.

The average glossiness was 69.3, and the deviation of glossiness was 4.7.

The average film thickness is 101.2 μm,
The unevenness of the film thickness was ± 9.2%.

This intermediate transfer belt (12) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt on the electrophotographic photosensitive member at the time of primary transfer is set to 0. It was set to 0.5N.

Image evaluation was carried out in the same manner as in Example 1. As a result, unevenness in the density of each image occurred in the initial stage, but this was not a problem.

Also, after 10,000 sheets of durability, it was about the same as the initial stage even after being left for one month.

(Comparative Example 1) Except that an outer mold (surface roughness Ra = 0.173 μm) whose inner surface was blasted was used,
An intermediate transfer belt (13) was produced in the same manner as in Example 1.

The average glossiness was 26.2, and the deviation of glossiness was 5.0.

The average film thickness is 100.1 μm,
The unevenness of the film thickness was ± 9.4%.

This intermediate transfer belt (13) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt on the electrophotographic photosensitive member at the time of primary transfer is 15N. And

When the image evaluation was performed in the same manner as in Example 1, unevenness in the density of each image occurred in the initial stage.

The same was true even after 10,000 sheets had been run for one month.

(Comparative Example 2) Thermoplastic polyimide resin 100 parts Carbon black 15 parts The above materials were melted by heating and extruded into a cylindrical shape at 350 ° C. The temperature for producing a tubular film is 33
It was set to 0 ° C. An intermediate transfer belt (14) was produced in the same manner as in Example 1 except that the above materials were used.

The average glossiness was 95.8 and the glossiness deviation was 4.5.

The average film thickness is 100.6 μm,
The unevenness of the film thickness was ± 9.1%.

This intermediate transfer belt (14) is incorporated in an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, a good full-color image was obtained without unevenness in the density of each image in the initial stage.

However, density unevenness occurred for each image after 10,000 sheets were run.

The same was true even after standing for 1 month.

(Comparative Example 3) An intermediate transfer belt (15) was produced in the same manner as in Example 1 except that the inner mold was changed in inner diameter to change the gap between the inner mold and the outer mold to 190 μm. Then,
Since the cylindrical film covered with the inner mold did not completely adhere to the outer mold during heating, unevenness in glossiness occurred on the surface of the film.

The average glossiness was 68.9 and the glossiness deviation was 13.8.

The average film thickness is 101.4 μm,
The unevenness of the film thickness was ± 8.6%.

This intermediate transfer belt (15) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

When the image evaluation was performed in the same manner as in Example 1, unevenness in the density of each image occurred in the initial stage.

The same was true even after 10,000 sheets were durable and left for one month.

(Comparative Example 4) An intermediate transfer belt was prepared in the same manner as in Example 1 except that a tubular film having a film thickness of 200 μm was used and the inner mold was changed in inner diameter to form a gap of 270 μm. (16) was produced.

The average glossiness was 69.9, and the deviation of glossiness was 4.4.

The average film thickness is 200.2 μm,
The unevenness of the film thickness was ± 7.6%.

This intermediate transfer belt (16) is incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, a good full-color image was obtained without causing unevenness in density for each image at the initial stage and after running 10,000 sheets.

However, unevenness in density occurred after leaving for 1 month.

(Comparative Example 5) An intermediate transfer belt was prepared in the same manner as in Example 1 except that a cylindrical film having a film thickness of 33 μm was used and the inner mold and outer mold gap was changed to 110 μm. (17) was produced.

The average glossiness was 69.7, and the glossiness deviation was 4.8.

The average film thickness was 33.3 μm, and the film thickness unevenness was ± 9.9%.

This intermediate transfer belt (17) was incorporated into an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer was 15N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, a good full-color image was obtained in the initial stage without unevenness in the density of each image.

However, after the durability test of 7600 sheets, the belt was damaged and printing became impossible.

(Comparative Example 6) An intermediate transfer belt (18) was produced in the same manner as in Example 1 except that the temperature at which a tubular film was produced by extrusion molding was 180 ° C.

The average glossiness was 69.4, and the deviation of glossiness was 4.2.

The average film thickness is 100.4 μm,
The unevenness of the film thickness was ± 32.1%.

This intermediate transfer belt (18) is incorporated in an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge having the structure shown in FIG. 5, and the pressing force of the intermediate transfer belt to the electrophotographic photosensitive member at the time of primary transfer is 15N. And

Image evaluation was carried out in the same manner as in Example 1. As a result, a good full-color image was obtained in the initial stage without unevenness in the density of each image.

After running 10,000 sheets, density unevenness occurred for each image, but this was not a problem.

However, unevenness in the density of each image occurred after leaving it for one month.

The results of Examples 1 to 12 and Comparative Examples 1 to 6 are shown in Table 1.

[0230]

[Table 1]

[0231]

As described above, according to the present invention, the maintenance is easy, the apparatus can be downsized and the cost can be reduced, and the density detection measurement for controlling the image forming conditions can be more stable and more stable. An intermediate transfer belt that can be accurately performed and that can obtain excellent images according to usage conditions
It has become possible to provide an electrophotographic photosensitive member integrated process cartridge, an electrophotographic apparatus having the process cartridge, an image forming method using the electrophotographic apparatus, and an intermediate transfer belt for the process cartridge.

[Brief description of drawings]

FIG. 1 is a schematic view of an electrophotographic apparatus provided with an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge of the present invention.

FIG. 2 is a schematic view of an intermediate transfer belt-electrophotographic photosensitive member integrated process cartridge of the present invention.

FIG. 3 is a schematic configuration diagram of a concentration detection sensor.

FIG. 4 is a schematic configuration diagram of an intermediate transfer belt molding apparatus of the present invention.

FIG. 5 is a schematic configuration diagram of a process cartridge used in Examples and Comparative Examples and configured by connecting an electrophotographic photoreceptor unit and an intermediate transfer belt unit.

FIG. 6 is a schematic configuration diagram of an intermediate transfer belt unit.

FIG. 7 is a schematic configuration diagram of an electrophotographic photosensitive member unit.

FIG. 8 is a diagram showing a state when the process cartridge of the present invention is attached to and detached from an electrophotographic apparatus.

FIG. 9 is a diagram showing a state of processing using a tubular film mold.

[Explanation of symbols]

1 Electrophotographic photoreceptor 2 Primary charging means 3 exposure light 5 Intermediate transfer belt 6 Primary transfer means (primary transfer counter roller) 7 Secondary transfer means (secondary transfer roller) 8 Secondary transfer counter roller 9 Charge imparting means 10 Transfer material guide 11 Paper feed roller 12 Tension roller 13 Electrophotographic photoreceptor cleaning means 14 Concentration detection sensor (concentration detection means) 141 light emitting element 142 Light receiving element 143 detection position 15 Fixing means 16 density patch 30, 31, 32, 33 Power supply 41 yellow color developing means 42 magenta color developing means 43 Cyan color developing means 44 Black color developing means P transfer material 100, 101 extruder 102 hopper 103 circular die 104 gas introduction path 105 External cooling ring 106 Stabilizer 107 pinch roller 108 cutting device 110 tubular film 45 Intermediate transfer belt frame 50 Electrophotographic photoconductor unit 51 Intermediate transfer belt unit 52 Waste toner container 53 cleaning blade 54 screw 55 drum shutter 58 Primary transfer roller 59 Electrophotographic photoconductor frame 60 Top cover of electrophotographic device 71 Projection 72 Positioning hole 72a Tapered part 73 Hook claw 74 Lock hole 160 tubular film 200 external type 201 Internal type

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hidekazu Matsuda             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation (72) Inventor Akihiko Nakazawa             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation (72) Inventor Tsunetoku Ashibe             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation (72) Inventor Takashi Kusaba             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation (72) Inventor Hiroyuki Kobayashi             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation F-term (reference) 2H134 GA01 GA06 GB02 HD00 KG04                       KH01 KH10 KJ02                 2H171 FA02 FA10 FA17 FA27 GA11                       JA23 JA26 JA27 JA30 JA31                       JA40 QA02 QA08 QA24 QA29                       QA30 QB04 QB34 QC03 QC22                       QC24 QC47 UA03 UA30 VA06                       WA02 WA03 WA10                 2H200 FA08 FA16 GA23 GA44 GB03                       GB12 HA03 HA28 HB12 JA02                       JB10 JC03 JC12 JC15 JC17                       JC18 LA38 LB02 LB03 LB13                       LB18 LB38 MA02 MC20 NA02

Claims (16)

[Claims] 1. A process cartridge detachably mountable to an electrophotographic apparatus main body, comprising: an electrophotographic photosensitive member for carrying a toner image; and an intermediate transfer belt having a contact portion with the electrophotographic photosensitive member. A primary transfer means for primarily transferring an image of the toner from the electrophotographic photosensitive member to the intermediate transfer belt at the contact portion; and toner on the intermediate transfer belt at the corresponding contact portion of the electrophotographic photosensitive member. In order to clean the intermediate transfer belt by returning to the above, integrally supporting a charge giving means for giving the toner on the intermediate transfer belt a charge having a polarity opposite to the polarity of the toner at the time of primary transfer, The average glossiness obtained in the circumferential direction of the intermediate transfer belt is 30 to 90, the deviation of the glossiness is 10 or less, and the average film thickness of the intermediate transfer belt is 40 to 200 μm. Intermediate transfer ± belt of thickness unevenness with respect to the average thickness 2
Process cartridge characterized by being within 0%. 2. The electrophotographic photosensitive member, the intermediate transfer belt, the primary transfer unit, the charge applying unit, and an electrophotographic photosensitive member cleaning unit for cleaning the electrophotographic photosensitive member are integrated. The electrophotographic photosensitive member unit having the electrophotographic photosensitive member and the intermediate transfer belt unit having the intermediate transfer belt can be separated from each other, and the electrophotographic photosensitive unit and the intermediate transfer belt unit are connected to each other. The process cartridge according to claim 1, further comprising a connecting means. 3. The electrophotographic photosensitive member when the image of the toner is primarily transferred from the electrophotographic photosensitive member to the intermediate transfer belt at a contact portion between the electrophotographic photosensitive member and the intermediate transfer belt. The process cartridge according to claim 1 or 2, wherein the pressing force of the intermediate transfer belt to the sheet is 1 to 50N. 4. The average glossiness obtained in the circumferential direction of the intermediate transfer belt is 40 to 85, the deviation of the glossiness is 9 or less, and the average film thickness of the intermediate transfer belt is 60 to 85. 4. The process cartridge according to claim 1, wherein the process cartridge has a thickness of 140 μm, and the thickness unevenness of the intermediate transfer belt is within ± 12% of the average film thickness. 5. The process cartridge according to claim 1, wherein the electrophotographic apparatus has a density detecting unit. 6. An electrophotographic photosensitive member for carrying a toner image, a charging unit for charging the electrophotographic photosensitive member, and an electrostatic latent image on the electrophotographic photosensitive member charged by the charging unit. An exposure unit for forming the image, a developing unit for developing the electrostatic latent image of the electrophotographic photosensitive member formed by the exposure unit with toner, and forming an image of the toner on the electrophotographic photosensitive member; An intermediate transfer belt having a contact portion with the electrophotographic photoreceptor for secondary transfer of the toner image transferred after the toner image is primarily transferred from the photoreceptor to the transfer material, and the contact portion At the primary transfer means for primarily transferring the image of the toner from the electrophotographic photosensitive member to the intermediate transfer belt, and returning the toner on the intermediate transfer belt to the electrophotographic photosensitive member at the contact portion. Clean the intermediate transfer belt In order to apply the electric charge to the toner on the intermediate transfer belt, an electric charge giving means for giving electric charge having a polarity opposite to that of the toner at the time of the primary transfer is provided, and at least the electrophotographic photoreceptor and the intermediate Transfer belt,
Integrally supporting the primary transfer means and the charge applying means,
The electrophotographic apparatus main body has a detachable process cartridge, the average glossiness obtained in the circumferential direction of the intermediate transfer belt is 30 to 90, and the glossiness deviation is 10 or less. The average film thickness of the intermediate transfer belt is 40 to 200 μm, and the film thickness unevenness of the intermediate transfer belt is ± 2 with respect to the average film thickness.
An electrophotographic apparatus characterized by being within 0%. 7. The electrophotographic photosensitive member for cleaning the electrophotographic photosensitive member, wherein the process cartridge includes the electrophotographic photosensitive member, the intermediate transfer belt, the primary transfer unit, the charge applying unit, and the charge transfer unit. A cleaning unit is integrally supported, and the process cartridge is separable into an electrophotographic photosensitive member unit having the electrophotographic photosensitive member and an intermediate transfer belt unit having the intermediate transfer belt. The electrophotographic apparatus according to claim 6, further comprising a connecting unit that connects the intermediate transfer belt unit and the intermediate transfer belt unit. 8. The electrophotographic photosensitive member when the toner image is primarily transferred from the electrophotographic photosensitive member to the intermediate transfer belt at a contact portion between the electrophotographic photosensitive member and the intermediate transfer belt. The electrophotographic apparatus according to claim 6 or 7, wherein the pressing force of the intermediate transfer belt to the sheet is 1 to 50N. 9. The average glossiness obtained in the circumferential direction of the intermediate transfer belt is 40 to 85, the deviation of the glossiness is 9 or less, and the average film thickness of the intermediate transfer belt is 60 to 85. 9. The electrophotographic apparatus according to claim 6, wherein the thickness of the intermediate transfer belt is 140 μm, and the unevenness of the film thickness of the intermediate transfer belt is within ± 12% of the average film thickness. 10. The electrophotographic apparatus according to claim 6, further comprising a density detecting unit. 11. A charging step of charging an electrophotographic photosensitive member, an exposure step of forming an electrostatic latent image on the electrophotographic photosensitive member charged in the charging step, and an electrophotographic photosensitive member formed in the exposure step. Developing the electrostatic latent image of with a toner to form an image of the toner on the electrophotographic photoreceptor, and the image of the toner formed by the developing step by the primary transfer means from the electrophotographic photoreceptor. A primary transfer step of primary transfer to an intermediate transfer belt having a contact portion with the electrophotographic photoreceptor, and a secondary transfer step of secondary transfer of the toner image primarily transferred in the primary transfer step to a transfer material. A charge applying step of applying a charge having a polarity opposite to the polarity of the toner at the primary transfer step to the toner on the intermediate transfer belt by the charge applying means, and the toner on the intermediate transfer belt at the contact portion. Return to the electrophotographic photoreceptor And an intermediate transfer belt cleaning step of cleaning the intermediate transfer belt with an electrophotographic photosensitive member and the intermediate transfer belt.
Integrally supporting the primary transfer means and the charge applying means,
An image forming method using an electrophotographic apparatus having a process cartridge detachably mountable to the main body of the electrophotographic apparatus, wherein the average glossiness obtained in the circumferential direction of the intermediate transfer belt is 30 to 90. The deviation of the glossiness is 10 or less, the average film thickness of the intermediate transfer belt is 40 to 200 μm, and the unevenness of the film thickness of the intermediate transfer belt is ± 2 with respect to the average film thickness.
An image forming method characterized by being within 0%. 12. An electrophotographic photosensitive member cleaning step of cleaning the electrophotographic photosensitive member after the intermediate transfer belt cleaning step, wherein the process cartridge includes the electrophotographic photosensitive member,
The process transfer cartridge integrally supports the intermediate transfer belt, the primary transfer unit, the charge applying unit, and the electrophotographic photosensitive member cleaning unit for cleaning the electrophotographic photosensitive member. 12. An electrophotographic photosensitive member unit having a body and an intermediate transfer belt unit having the intermediate transfer belt, which are separable from each other, and having a connecting means for connecting the electrophotographic photosensitive member unit and the intermediate transfer belt unit. The image forming method described. 13. The image forming method according to claim 11, wherein, in the primary transfer step, the intermediate transfer belt is brought into contact with the electrophotographic photosensitive member with a pressing force of 1 to 50 N. 14. The average glossiness obtained in the circumferential direction of the intermediate transfer belt is 40-85, the deviation of the glossiness is 9 or less, and the average film thickness of the intermediate transfer belt is 60-85. The image forming method according to claim 11, wherein the thickness of the intermediate transfer belt is 140 μm, and the unevenness of the film thickness of the intermediate transfer belt is within ± 12% of the average film thickness. 15. The image forming method according to claim 11, wherein an electrophotographic apparatus having a density detecting means is used. 16. An intermediate transfer belt for use in the process cartridge according to claim 1.