JP5402438B2 - Image forming apparatus and control method thereof - Google Patents

Description

  The present invention relates to an image forming apparatus and a control method thereof, and more particularly, to a blade curling prevention technique for a cleaning blade that cleans a toner image after the toner image is formed on an intermediate transfer member.

  Conventionally, an image forming apparatus such as a copying machine or a laser beam printer using an electrophotographic method uses an intermediate transfer member. In this method, after the toner image is primarily transferred to the intermediate transfer member, the toner image is secondarily transferred from the intermediate transfer member to a recording material such as transfer paper by a transfer roller or the like. In such an image forming apparatus, an image carrier (hereinafter also referred to as a photosensitive member) or an intermediate transfer member is cleaned of residual transfer toner in the case of a photosensitive member, on the downstream side in the rotation direction of the photosensitive member from the primary transfer position. In the case of a transfer body, one in which an elastic blade made of urethane rubber or the like is in contact with the downstream side of the secondary transfer position in the rotational direction of the intermediate transfer body is known.

  In an image forming apparatus having such a blade cleaning device, residual toner as a lubricant on the surface of the blade, the photosensitive member, and the intermediate transfer member is depleted by continuous paper passing at a small size or continuous paper passing at a low image ratio. However, this causes a phenomenon that the cleaning blade is turned up. This phenomenon is particularly remarkable in a high-temperature and high-humidity environment, and the blade is often turned over from the end of the cleaning blade.

  In order to solve this phenomenon, a belt-like toner image is created in the longitudinal direction of the blade in the non-image area of the image carrier or intermediate transfer member as in Patent Document 1 (hereinafter referred to as a blade blur prevention pattern). It has been proposed to sometimes perform an operation of lowering the friction coefficient between the blade and the image carrier or intermediate transfer member when the blade reaches the blade edge.

  On the other hand, in an image forming apparatus, in order to improve the stability of an image, a density adjustment pattern or a positional deviation adjustment pattern is formed between images (hereinafter also referred to as a paper interval), and the pattern is detected to supply the amount of toner, etc. A method of feeding back to the image forming conditions is generally known. Also, as one of such adjustment patterns, a method of forming a pattern for consuming toner according to the image area ratio has been proposed in order to stabilize the toner state in the developing device as in Patent Document 2. Yes.

  The blade blur prevention pattern and various adjustment patterns form a new pattern image such as a solid patch or a solid band only for that purpose, and waste toner for purposes other than image formation. Will be.

  Therefore, Patent Document 3 proposes a method for suppressing wasteful toner consumption by extending a part of the correction pattern in the longitudinal direction and using the correction pattern and the blade wobbling prevention pattern together.

  Further, Patent Document 4 proposes a method in which a blade swell prevention pattern is formed according to the travel distance of the intermediate transfer member to suppress blade breakage and reduce wasteful toner consumption.

  Further, Patent Documents 5 and 6 propose a method of suppressing wasteful toner consumption by changing the shape and density of the blade blur prevention pattern according to the image density.

  However, in the method of Patent Document 3, the difference in density appears in the image quality correction patch because the current flowing in the patch portion differs in the longitudinal direction for preventing blade wobbling and only in the case of the patch. There arises a problem that results are shifted.

  In the method of Patent Document 4, since the image area ratio of the printed image is not taken into consideration, when printing is performed at a low image area ratio, it is effective because there is little transfer residual toner. In the case of the rate, since there is a large amount of toner remaining after transfer, the toner is sufficiently input to the cleaning blade, and wasteful toner consumption is performed.

  Furthermore, in the methods of Patent Documents 5 and 6, the density of the printed image is detected, but the correction patch created between the sheets is not detected. For this reason, blade correction patterns based on the image density are also created in the correction patch portions that are not transferred to the transfer material, and excessive toner is input to the cleaning blade corresponding to the correction patch portion. become. Thus, wasteful toner consumption is performed. In addition, when excessive toner is input in a low temperature environment, a so-called cleaning failure may occur in which the toner in the portion cannot be removed by the cleaning blade and the toner slips through.

  The present invention has been made in view of the above problems, and an object of the present invention is to prevent cleaning blade curling and cleaning failure, and to suppress wasteful toner consumption by efficiently forming a blade curling prevention pattern. Therefore, it is an object of the present invention to provide a highly productive image forming apparatus and a control method therefor.

In order to achieve the above object, the present invention provides, as a first aspect, exposure for exposing image light to a latent image carrier, a charging member that contacts the surface of the latent image carrier, and the surface of the latent image carrier charged by the charging member. Developing means for converting the latent image formed by the exposure into a visible image, transferring means for transferring the visible image to a transfer material via an intermediate transfer member, and the transferring means An image forming apparatus having a cleaning blade for cleaning the surface of the intermediate transfer member after the transfer is completed by forming a toner image as a blade wrinkle prevention pattern between the images, and cleaning the toner image of the blade wrinkle prevention pattern blade is cleaned, as the blade curling prevention pattern, the portion except for the portion corresponding to the pattern of image-quality adjustment formed between the image immediately before, immediately before There is provided an image forming apparatus, characterized in that to create the intended toner amount determined based on the area ratio of the output image.

In order to achieve the above object, as a second aspect, the present invention exposes image light to the latent image carrier, a charging member that contacts the surface of the latent image carrier, and the surface of the latent image carrier charged by the charging member. Exposing means for developing, developing means for making a latent image formed by the exposure visible, transfer means for transferring the visible image to a transfer material via an intermediate transfer member, and A control method of an image forming apparatus comprising a cleaning blade for cleaning the surface of an intermediate transfer member after completion of transfer by a transfer unit, wherein a toner image as a blade blur prevention pattern is formed between images, and the blade blur prevention pattern to clean the toner image on the cleaning blade, as the blade curling prevention pattern, the portion corresponding to the pattern of image-quality adjustment formed between the image immediately before The Ku portion, there is provided a method of controlling an image forming apparatus, characterized in that to create the intended toner amount determined based on the area ratio of the output image immediately before.

  According to the present invention, it is possible to prevent cleaning blade curling and poor cleaning, and it is possible to suppress wasteful toner consumption by efficiently forming a blade curling prevention pattern.

1 is a diagram illustrating a configuration of an image forming apparatus according to a first exemplary embodiment of the present invention. It is a schematic diagram for demonstrating the cleaning blade dripping prevention pattern of Example 1 of this invention. It is a flowchart at the time of the braid | blade twist prevention pattern preparation of Example 1 of this invention. It is a flowchart at the time of the preparation of the blade twist prevention pattern of Example 2 of the present invention. 6 is a schematic diagram for explaining a cleaning blade wobbling prevention pattern of Comparative Example 1. FIG. 10 is a flowchart when creating a blade wobbling prevention pattern of Comparative Example 1; 10 is a schematic diagram for explaining a cleaning blade wobbling prevention pattern of Comparative Example 2. FIG. 10 is a flowchart when creating a blade wobbling prevention pattern of Comparative Example 2;

Example 1
FIG. 1 is a schematic layout diagram showing an example of an image forming apparatus according to the first embodiment. The image forming apparatus shown in FIG. 1 is a copying machine capable of optical writing corresponding to image information. The present invention can be applied not only to the above-described copying machine but also to a printer, a facsimile machine, or a printing machine as an image forming apparatus.

  The copying machine 1 includes a plurality of photosensitive members 2 as latent image carriers that use a drum. Around the photosensitive member 2, a charging device 3 for performing image forming processing in a clockwise rotation process, writing A device 4, a developing device 5, a transfer device 6 and a cleaning device 7 are arranged. In the first embodiment, the photoconductor 2 is arranged in tandem.

  In the copying machine 1, an electrostatic latent image is formed on the photosensitive member 2 by optical writing according to image information after the uniform charging process by the charging device 3 during the rotation of the photosensitive member 2, and the electrostatic latent image is developed by the developing device. A visible image is processed with an image forming material (hereinafter referred to as toner) supplied from 5 to form a toner image. In the first exemplary embodiment, a negative polarity voltage is applied to the charging device 3 to charge the photoreceptor 2.

  The toner image carried on each photoconductor 2 is transferred to the intermediate transfer belt 8A at the primary transfer nip 8C. As a configuration thereof, in the first embodiment, a primary transfer roller 8B which is a transfer bias unit is used, and a positive polarity voltage is applied. In the first embodiment, the transfer unit is a roller, but other contact type transfer units or non-contact type transfer units such as a transfer charger may be used.

  In the first embodiment, the belt 8A is a belt having a film thickness of 60 μm in which PI (polyimide) is formed as a single layer. As the belt 8A, a belt constituted by PVDF (vinylidene fluoride), ETFE (ethylene-tetrafluoroethylene copolymer), PI (polyimide), PC (polycarbonate) or the like in a single layer or a plurality of layers may be used. Is possible. If necessary, a release layer may be coated on the surface of the belt 6A.

  Materials used for the coating include ETFE (ethylene-tetrafluoroethylene copolymer), PTFE (polytetrafluoroethylene), PVDF (vinylidene fluoride), PEA (perfluoroalkoxy fluorocarbon resin), FEP (four-fluorocarbon). Fluorine resin such as ethylene fluoride-propylene hexafluoride copolymer) or PVF (vinyl fluoride) can be used, but is not limited thereto. The manufacturing method of the belt 6A includes a casting method, a centrifugal molding method, and the like, and the surface thereof may be polished if necessary.

  Further, a belt material (endless belt) having a three-layer structure of a base layer, an elastic layer, and a coat layer may be used. In the case of a belt having a three-layer structure, the base layer is made of a material obtained by combining, for example, a fluorine-based resin having a small elongation or a rubber material having a large elongation with a material that is difficult to stretch, such as a canvas. The elastic layer is made of, for example, fluorine rubber or acrylonitrile-butadiene copolymer rubber, and is formed on the base layer. The coat layer is formed by coating the surface of the elastic layer with, for example, a fluorine resin.

  The belt 8A has a resistivity adjusted by dispersing a conductive material such as carbon black, and the volume resistivity is 108 to 1012 Ωcm and the surface resistivity is 109 to 1013 Ωcm. desirable.

  The volume resistivity and surface resistivity of the belt 8A are not limited to the above ranges, but if the volume resistivity of the belt 8A exceeds the above range, the bias required for transfer increases, which increases the power supply cost. There is a possibility of inviting. Further, the charging potential of the belt 8A becomes high in the transfer process, the transfer paper peeling process, and the like, and self-discharge becomes difficult. If the volume resistivity and surface resistivity are below the above ranges, the charge potential decays faster, which is advantageous for static elimination by self-discharge. However, toner scatter may occur because the current during transfer flows in the surface direction. There is.

  The volume resistivity and surface resistivity were measured by connecting an HRS probe (inner electrode diameter 5.9 mm, ring electrode inner diameter 11 mm) to a high resistivity meter (manufactured by Mitsubishi Chemical Corporation: Hiresta IP), and the front and back of the belt 8A. The measured value 10 seconds after applying a voltage of 100 V (surface resistivity is 500 V) was used.

  The toner image transferred on the intermediate transfer belt 8A is transported to the secondary transfer portion 8B, and transferred in time with the transfer material P transported from a paper feeding device (not shown). As the secondary transfer means, a secondary transfer roller 9 and a repulsive roller 10 are used, and electrostatic transfer using repulsive force is performed by applying a negative bias to the repulsive roller. As the secondary transfer means, contact type transfer means other than the transfer roller, or non-contact type transfer means such as a transfer charger can be used.

  The transfer residual toner remaining on the intermediate transfer belt after the secondary transfer is scraped by the cleaning blade 11 and proceeds to the next image formation.

  The cleaning blade 11 is made of a material such as metal, resin, or rubber, but rubber such as fluorine rubber, silicone rubber, butyl rubber, butadiene rubber, isoprene rubber, or urethane rubber is preferably used. In this embodiment, urethane rubber which is particularly suitable among them is used and is brought into contact with the intermediate transfer belt 8A by a counter method. The number of cleaning blades is not limited to one, and a plurality of blades may be arranged. Also, the contact method is not limited to the counter method, and when a trailing method or a plurality of blades are arranged, an arrangement in which both methods are interwoven may be performed.

  Next, the cleaning blade wobbling prevention pattern in the first embodiment will be described.

FIG. 2 is a schematic diagram when five images are printed.
In FIG. 2, the blade squeezing prevention pattern creation interval is set to two. In addition, when the area ratio of the output image is 5% or more, the setting is made so that the blade blur pattern density is reduced.
Further, the length L in the rotational direction of the intermediate transfer belt of the blade deflection preventing pattern was 5 mm.

Since the creation interval is two, a blade wrinkle prevention pattern is created between the second and third sheets of output image and between the fourth and fifth sheets (Bp2, Bp4). . At this time, the width of the blade twist prevention pattern is Wb, which is substantially the same as the width of the cleaning blade. Further, since the area ratio of the output image immediately before the blade blurring prevention pattern was 10%, the density of the output image width Wi was made thin. In this embodiment, a method of changing the adhesion amount per unit area is adopted. Specifically, the adhesion amount per unit area of the normal cleaning blade wrinkle prevention pattern is 0.5 mg / cm ² , whereas the adhesion amount per unit area of the width Wi portion is 0.25 mg / cm ^2. It was.

  As a method for reducing the pattern density, other methods such as a method for changing the area of the pattern as well as a method for changing the adhesion amount per unit area may be used.

  Further, the blade twist prevention pattern Bp2 created between the second and third sheets has a density adjustment pattern created between the immediately preceding sheets (between the first and second sheets) ( Width Wp) No part of the pattern corresponding to the width Wp of the density adjustment pattern in the blade twist prevention pattern Bp2 was created.

FIG. 3 is a flowchart at the time of creating a blade drooling prevention pattern.
First, it is determined whether it is a pattern creation interval (step S101). If it is not the pattern creation interval, the process ends without creating the blade squeezing prevention pattern, and the next image is created.

  If it is the pattern creation interval, it is next determined whether another image adjustment pattern is created (step S102). When another image adjustment pattern is created (step S102 / Yes), information for creating a blade squeezing prevention pattern between the next sheets is stored in a recording medium (not shown) such as a memory and the process is terminated (step S102). S110). If no other image adjustment pattern is created (step S102 / No), the blade wobbling prevention pattern can be created, and the conditions are set.

  First, the remaining amount of toner is calculated (step S103). In the first embodiment, four colors Y, C, M, and K are calculated. The formula for calculating the remaining amount of toner used in the first embodiment will be described below. However, as a calculation method, another calculation method or a method of measuring the actual remaining amount of toner at any time may be used.

The toner remaining amount M is calculated by Equation 1.
Formula 1) Remaining toner amount M [mg] = initial weight Ms [mg] −toner consumption amount Mw [mg]
The initial weight Ms is recorded in advance on a recording medium (not shown) such as a memory.

The toner consumption amount Mw is calculated by Equation 2.
Formula 2) Toner consumption Mw [mg] = cumulative image area [cm ² ] × target adhesion amount [mg / cm ² ]
The accumulated image area is always calculated at the time of image formation by a control means such as a CPU, and the target adhesion amount is also preset in the control means such as a CPU.

  Next, from the calculation result of the remaining amount of toner, the toner having the largest amount of remaining toner is selected and set as a pattern creation color (step S104).

  Next, it is determined whether the area ratio of the immediately preceding image is 5% or more (step S105). The threshold of the area ratio is not limited to 5%, and can be set arbitrarily. When the image area ratio is 5% or more, the density of the pattern corresponding to the image width Wi is lowered (step S106). When the image area ratio is less than 5%, the pattern density corresponding to the image width Wi is not changed.

Next, it is determined whether various adjustment patterns have been created between the immediately preceding sheets (step S107).
When various adjustment patterns are created, after deleting the portion corresponding to the width Wp of the created adjustment pattern, create a blade squeeze prevention pattern, and various adjustment patterns for creating the next image are not created Creates a blade drooling prevention pattern as it is and creates the next image (steps S108 and S109).

(Example 2)
The second embodiment is a system in which the creation interval of the blade wobbling prevention pattern is determined based on the designated number of sheets and the temperature / humidity detection result with respect to the configuration of the first embodiment. Here, only the blade squeezing prevention pattern creation flow, which is a difference from the first embodiment, will be described, and the other parts are the same as those of the first embodiment, and are omitted.

  The temperature / humidity detection means is most preferably installed near the cleaning blade 11, but detection results at other parts in the machine or detection results of outside air temperature / humidity may be used.

FIG. 4 is a flowchart at the time of creating a blade wobbling prevention pattern in the second embodiment.
First, it is determined whether it is a pattern creation interval (step S101). If it is not the pattern creation interval, the process ends without creating the blade squeezing prevention pattern, and the next image is created.

If it is the pattern creation interval, the temperature / humidity detection result is referenced next to determine whether the temperature is equal to or higher than the threshold temperature / humidity (step S111). In Example 2, only the temperature was used as the threshold, and the value was set to 40 degrees. If the temperature / humidity detection result is less than the threshold, the process ends without creating the blade squeezing prevention pattern, and the next image is created. If the temperature / humidity detection result is equal to or greater than the threshold value, it is next determined whether another image adjustment pattern is to be created (step S102).
Since the subsequent flow is the same as that of the first embodiment, it is omitted.

(Comparative Example 1)
The first comparative example is a method that determines the creation interval of the blade squeezing prevention pattern based on only the designated number of sheets in the configuration of the first embodiment, and is similar to the method described in Patent Document 1 as the prior art.

The creation color of the blade wrinkle prevention pattern created in Comparative Example 1 is black, the adhesion amount per unit area is 0.5 mg / cm ² , the width is almost the same as the cleaning blade, and the length in the intermediate transfer belt rotation direction is 5 mm. did.

  FIG. 5 is a schematic diagram when five images are printed in Comparative Example 1 and the blade twist prevention pattern creation interval is two.

FIG. 6 is a flowchart at the time of creating a blade wobbling prevention pattern in Comparative Example 1.
First, it is determined whether it is a pattern creation interval (step S101). If it is not the pattern creation interval, the process ends without creating the blade squeezing prevention pattern, and the next image is created.
If it is the pattern creation interval, a blade wobbling prevention pattern is created, and the next image is created (step S109).

(Comparative Example 2)
Comparative Example 2 is a system in which the blade wobbling prevention pattern is also used as another image adjustment pattern for the configuration of Example 1, and is similar to the system described in Patent Document 3 as the prior art.

The creation color of the blade wrinkle prevention pattern created in Comparative Example 2 is black, the adhesion amount per unit area is 0.5 mg / cm ² , the width is almost the same as the cleaning blade, and the length in the rotation direction of the intermediate transfer belt is 5 mm. did.

  FIG. 7 is a schematic diagram when five images are printed in Comparative Example 2 and the blade twist prevention pattern creation interval is two. In addition, the pattern creation interval for image adjustment is four. For this reason, once in every two sheets, a blade squeezing prevention pattern and an image adjustment pattern are created between the same sheets.

FIG. 8 is a flowchart at the time of creating a blade wobbling prevention pattern in Comparative Example 2.
First, it is determined whether it is a pattern creation interval (step S101). If it is not the pattern creation interval, the process ends without creating the blade squeezing prevention pattern, and the next image is created.

  If it is the pattern creation interval, it is next determined whether another image adjustment pattern is created (step S102). If no other image adjustment pattern is created, a normal blade wobbling prevention pattern is created, and the next image is created (step S112). When other image adjustment patterns are created, both the blade blur prevention pattern and the image adjustment pattern are created, and the next image is created (step S113). However, only the image adjustment pattern is created for the portion where both patterns intersect. In FIG. 7, the pattern density for image adjustment is displayed lightly for convenience, but the pattern for image adjustment has a density according to the adjustment control.

  Using each configuration of Example 1, Example 2, Comparative Example 1, Comparative Example 2, and Comparative Example 3 (no blade swell prevention pattern is created), a paper passing experiment was performed under the following conditions.

Condition 1
Print image area ratio: 20% (5% for each color)
Blade wrinkle prevention pattern creation interval: 1/10 sheets Density adjustment pattern creation interval: 1/3 sheets Environment: 3 environments of 10 ° C 15%, 23 ° C 50%, 27 ° C 80% Number of sheets passed: 20K for each environment Sheet

Condition 2
Print image area ratio: 2% (each color 0.5%)
Blade wrinkle prevention pattern creation interval: 1/10 sheets Density adjustment pattern creation interval: 1/3 sheets Environment: 3 environments of 10 ° C 15%, 23 ° C 50%, 27 ° C 80% Number of sheets passed: 20K for each environment Sheet

Evaluation item Blade squeezing ・ ・ ・ No occurrence: ○, Occurrence ・ ・ ・ ×
Cleaning failure ... No occurrence: ○, Occurrence ... ×
Density adjustment error: No occurrence: ○, Occurrence ... ×

  Table 1 shows the evaluation results of Condition 1, and Table 2 shows the evaluation results of Condition 2.

In Examples 1 and 2, there was no cleaning blade wobbling, no cleaning failure, and no density adjustment error.
In Comparative Example 1, cleaning failure occurred in an environment of 10 ° C. and 15%.
In Comparative Example 2, a cleaning failure occurred in an environment of 10 ° C. and 15%, and a density adjustment error occurred in each environment.
In Comparative Example 3, a cleaning failure occurred in an environment of 10 ° C. and 15%, and blade curling occurred in an environment of 27 ° C. and 80%.

Tables 3 and 4 show the results of measuring the remaining amount of toner at the time of passing 20K sheets in each experiment.
The initial toner weight was adjusted to 500 g at the start in each environment.

In Examples 1 and 2, the remaining amount of toner is larger than those in Comparative Examples 1 and 2. In other words, wasteful toner consumption was not confirmed, and the effect of the present invention was confirmed.
Compared to Comparative Example 3, the toner consumption is large. However, in Comparative Example 3, cleaning failure and blade curl occurred, whereas in Examples 1 and 2, no problem occurred. Thus, according to the present invention, wasteful toner consumption can be suppressed, and problems such as blade curl and poor cleaning can be prevented.

  According to the above-described embodiments of the present invention, it is possible to provide a highly productive image forming apparatus by preventing the cleaning blade from being bent or from being poorly cleaned and by efficiently forming a blade turning prevention pattern.

  In addition, by using a toner color having the largest amount of remaining toner as the creation color of the blade blur prevention pattern, wasteful toner consumption can be suppressed, and an image forming apparatus with high productivity can be provided.

  Further, by changing the toner amount of the blade blur prevention pattern by changing the adhesion amount per unit area, the blade blur prevention pattern can be efficiently formed, and an image forming apparatus with high productivity can be provided.

  Further, by changing the toner amount of the blade blur prevention pattern while changing the size of the pattern area, the blade blur prevention pattern can be efficiently formed, and an image forming apparatus with high productivity can be provided.

  In addition, the amount of toner in the blade blur prevention pattern is calculated based on the blank area of the previous output image and determined based on the calculation result, so that the blade blur prevention pattern can be formed efficiently, and image formation with high productivity is achieved. Equipment can be provided.

  In addition, by determining the blade wrinkle prevention pattern creation interval based on the number of printed sheets, the blade wrinkle prevention pattern can be efficiently formed, and an image forming apparatus with high productivity can be provided.

  In addition, the image forming apparatus includes a temperature / humidity detection unit, and the blade wobbling prevention pattern creation interval is determined based on the temperature / humidity detection result, so that the blade wobbling prevention pattern can be efficiently formed and the productivity is high. An image forming apparatus can be provided.

  Also, the width of the blade wrinkle prevention pattern is substantially the same as the width of the cleaning blade, so that the blade wrinkle prevention pattern can be formed efficiently, and an image forming apparatus with high productivity can be provided.

  Further, the intermediate transfer member is an endless intermediate transfer belt that is pressed against the image carrier and is laid on a plurality of rollers, and includes a cleaning blade for removing toner remaining on the intermediate transfer belt. Even in the belt system, a blade wobbling prevention pattern can be efficiently formed, and an image forming apparatus with high productivity can be provided.

  In addition, since the latent image carrier is a tandem type in which a plurality of latent image carriers are arranged in parallel to face the intermediate transfer member, a blade wrinkle prevention pattern can be efficiently formed even in a full-color image forming apparatus, resulting in high productivity. An image forming apparatus can be provided.

  Note that the present embodiment is merely an example and does not limit the present invention. Therefore, various improvements and modifications can be made to the present invention without departing from the scope of the present invention. For example, although the present embodiment is provided by a tandem type copying machine, the present invention is not limited to this, and can also be applied to a four-cycle type copying machine or a copying machine having only one image carrier.

DESCRIPTION OF SYMBOLS 1 Copying machine 2 Photoconductor 7 Cleaning apparatus 8 Intermediate transfer belt 11 Cleaning blade

Japanese Patent Laid-Open No. 11-219094 JP 2006-171521 A JP-A-2005-181408 Japanese Patent No. 4106932 JP-A-2005-106920 JP 2006-251138 A

Claims (13)

A latent image carrier, a charging member that contacts the surface of the latent image carrier, an exposure unit that exposes image light to the surface of the latent image carrier charged by the charging member, and a development that makes the latent image formed by the exposure visible An image provided with a transfer means for transferring the formed visible image to a transfer material via an intermediate transfer body, and a cleaning blade for cleaning the surface of the intermediate transfer body after the transfer by the transfer means is completed. A forming device,
Forming a toner image as a blade blurring prevention pattern between images, causing the cleaning blade to clean the toner image of the blade blurring prevention pattern,
As the blade blur prevention pattern , creating a toner amount determined based on the area ratio of the immediately preceding output image in a portion excluding the portion corresponding to the pattern shape for image quality adjustment formed between the immediately preceding images. An image forming apparatus. The image forming apparatus according to claim 1, wherein a creation color of the blade blur prevention pattern is determined based on a remaining amount of toner.   The image forming apparatus according to claim 2, wherein a creation color of the blade blur prevention pattern is a toner color having the largest amount of remaining toner. The amount of toner of the blade blur prevention pattern created in a portion excluding the portion corresponding to the image shape adjustment pattern shape formed between the immediately preceding images is determined based on the area ratio of the immediately preceding output image. The image forming apparatus according to any one of claims 1 to 3. When changing the toner amount of the blade squeeze prevention pattern created in the portion excluding the portion corresponding to the pattern shape for image quality adjustment formed between the immediately preceding images, the amount of adhesion per unit area should be changed. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. When changing the toner amount of the blade blur prevention pattern created in a portion excluding the portion corresponding to the pattern shape for image quality adjustment formed between the immediately preceding images , the pattern area size is changed. The image forming apparatus according to any one of claims 1 to 5.   The image forming apparatus according to claim 1, wherein the creation interval of the blade wrinkle prevention pattern is determined based on the number of printed sheets. A temperature and humidity detection means is provided in the vicinity of the cleaning blade,
8. The image forming apparatus according to claim 1, wherein the creation interval of the blade blur prevention pattern is determined based on a detection result by the temperature and humidity detection unit.   9. The image forming apparatus according to claim 1, wherein a width of the blade curling prevention pattern is substantially the same as a width of the cleaning blade. 10. The intermediate transfer member is an endless intermediate transfer belt that is in pressure contact with the image carrier and is laid on a plurality of rollers.
The image forming apparatus according to claim 1, wherein the cleaning blade removes toner remaining on the intermediate transfer belt.   11. The image forming apparatus according to claim 1, wherein the latent image carrier is a tandem type in which a plurality of the latent image carriers are arranged to face the intermediate transfer member.   When the creation timing of the blade blur prevention pattern and the creation timing of the pattern shape for image quality adjustment are the same, information is stored that creates the blade blur prevention pattern at the next timing, and The image forming apparatus according to claim 1, wherein only the pattern shape for image quality adjustment is created at the timing. A latent image carrier, a charging member that contacts the surface of the latent image carrier, an exposure unit that exposes image light to the surface of the latent image carrier charged by the charging member, and a development that makes the latent image formed by the exposure visible An image provided with a transfer means for transferring the formed visible image to a transfer material via an intermediate transfer body, and a cleaning blade for cleaning the surface of the intermediate transfer body after the transfer by the transfer means is completed. A method for controlling a forming apparatus, comprising:
Form a toner image as a blade blur prevention pattern between images,
Causing the cleaning blade to clean the toner image of the blade blur prevention pattern;
As the blade blur prevention pattern , creating a toner amount determined based on the area ratio of the immediately preceding output image in a portion excluding the portion corresponding to the pattern shape for image quality adjustment formed between the immediately preceding images. A control method for an image forming apparatus.

Images