JP6926561B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus.

Conventionally, an image forming apparatus that is provided with a cleaning device that brings a plate-shaped cleaning member into contact with an image holder such as a photoconductor or a transfer body and is configured to supply toner or a lubricant to the image holder is exemplified below. Those described in the patent documents are known.

For example, Patent Document 1 below describes an electrostatic latent image holder, a charging device that charges the surface of the electrostatic latent image holder by applying a charging voltage, and static electricity formed on the electrostatic latent image holder. It is equipped with a developing device that develops a latent image with toner and a cleaning device that has a plate-shaped elastic member for cleaning that comes into contact with the surface of an electrostatic latent image holder and cleans the transfer residual toner. An image forming apparatus is shown in which an electrostatic latent image holder is rotated without applying a charging voltage to the charging apparatus to supply toner and an external additive to a cleaning plate-shaped elastic member.

Further, in Patent Document 2 below, a transfer body, a plurality of image forming portions including a photoconductor, a charging device, a developing device, a transfer device, and a cleaning device, and a lubricant holding member arranged in contact with the surface of the transfer body are described. A lubricant supply bias applying device, a lubricant transfer bias applying device, and a control unit of each of the bias applying devices are provided, and the control unit determines the amount of toner adhering based on the image data to be formed in the image forming mode. An image forming apparatus is shown in which a lubricant is transferred from a lubricant holding member via a transfer body and supplied to a non-image region on the surface of a photoconductor, which is less than a predetermined amount of adhesion.

Japanese Unexamined Patent Publication No. 2008-185919 Japanese Unexamined Patent Publication No. 2009-271458

According to the present invention, when forming a toner image according to image information, it is difficult to see the toner image in a non-image area where the toner image is not formed. It is an object of the present invention to provide an image forming apparatus capable of efficiently supplying toner to a portion in contact with a member with less unevenness.

The image forming apparatus of the present invention (A1) is
An image-forming means for forming a toner image according to image information,
An image holder that rotates to hold and transfer the toner image formed by the image forming means,
A cleaning device that brings a plate-shaped cleaning member into contact with the image holder,
When the toner image is formed by the image-forming means, a supplementary toner image that is difficult to see is formed in a non-image area where the toner image is not formed and held by the image holder, and the supplementary toner image is not transferred. A control means for executing an operation of bringing the toner remaining in the image holder to a portion in contact with the cleaning member, and
A reading means for reading the color of the recording medium on which the toner image is transferred and the density of the image consisting of the toner image transferred to the recording medium.
Equipped with a,
The control means either one of the toner colors and the amount used in the image forming means when forming the supplementary toner image based on the reading information regarding the color of the recording medium and the density of the image obtained from the reading means. It adjusts both .

In the image forming apparatus of the present invention (A2), in the image forming apparatus of the invention A1, the control means controls to form the supplementary toner image in a part of the non-image area.
The image forming apparatus of the present invention (A3) is the image forming apparatus of the invention A2, wherein the control means distributes the supplementary toner image in the width direction intersecting the rotation direction of the image holder in the non-image area. It is controlled so that it is formed in a state where it is allowed to form .

The image forming apparatus of the present invention (A 4), in any one of the image forming apparatus A 3 from the invention A1, includes a transparent image forming means for forming a transparent toner image formed of clear toner as the image forming means, The control means controls the transparent image forming means to form the supplementary toner image.
The image forming apparatus of the present invention (A 5), in the image forming apparatus of the invention A 4, the surface gloss of the recording medium on which an image consisting of a surface gloss of the recording medium to transfer said toner image wherein the toner image is formed The control means includes a gloss reading means for reading the degree, and the control means is based on the reading information regarding the surface gloss of the recording medium obtained from the gloss reading means and the surface gloss of the recording medium on which the image is formed. The amount of the colorless transparent toner used in the transparent image forming means when forming an image is adjusted.

The image forming apparatus of the present invention (A 6), in any one of the image forming apparatus A 5 from the invention A1, the control means, according to one or both of the information forming amount and continuous formation time of the toner image Therefore, the formation of the supplementary toner image is controlled to be interrupted, or the formation pattern of the supplementary toner image or the change in the direction of reducing the amount of toner used is controlled.

The image forming apparatus of the present invention (A 7), in any one of the image forming apparatus A 6 from the invention A1, provided with a latent image holding member and the intermediate transfer member as the image carrier, the latent as the cleaning device A first cleaning device for contacting the plate-shaped cleaning member with the image holder and a second cleaning device for contacting the plate-shaped cleaning member with the intermediate transfer body are provided.
The control means holds the supplementary toner image on the latent image holder and the intermediate transfer body, respectively, and removes the toner that is not transferred from the supplementary toner image and remains on the latent image holder in the first cleaning device. The operation of reaching the part where the cleaning member of the second cleaning member comes into contact and the operation of causing the toner remaining in the intermediate transfer body, which is not transferred from the supplementary toner image, to reach the part of the second cleaning device in contact with the cleaning member are executed. It is a thing.
The image forming apparatus of the present invention (A 8) is in any of the image forming apparatus A 6 from the invention A1, contacting the recording medium and the latent image holding member on the latent image holding member as said image carrier passes A medium-shaped cleaning device is provided, and as the cleaning device, a plate-shaped cleaning member is brought into contact with the latent image holder, and a plate-shaped cleaning member is brought into contact with the medium-carrying body. Equipped with equipment
The control means holds the supplementary toner image on the latent image holder and the medium carrier, and cleans the toner image of the supplementary toner image that is not transferred and remains on the latent image holder for cleaning the first cleaning device. The operation of reaching the portion where the member contacts and the operation of causing the toner remaining in the medium carrier, which is not transferred from the supplementary toner image, to reach the portion where the cleaning member of the third cleaning device contacts. be.
The image forming apparatus of the present invention (A 9), in any one of the image forming apparatus A 8 from the invention A1, as a recording medium for transferring the toner image, is to use the medium continuous.

According to the image forming apparatus of the invention A1, when forming a toner image according to image information, a rotating image is compared with a case where a supplementary toner image that is difficult to see in a non-image area where the toner image is not formed is not formed. Toner can be efficiently supplied to the portion of the holder where the plate-shaped cleaning member comes into contact with less unevenness. Further, in this image forming apparatus, compared with the case where one or both of the toner color and the amount used when forming a supplementary toner image by the image forming means based on the reading information regarding the color of the recording medium and the density of the image is not adjusted. Therefore, it is possible to accurately suppress the change in the color tone of the image due to the transfer of a part of the toner of the supplementary toner image to the recording medium.

In the image forming apparatus of the invention A2, the consumption of the toner used for forming the supplementary toner image can be suppressed as compared with the case where the supplementary toner image is not formed in a part of the non-image area.
In the image forming apparatus of the above invention A3, the toner consumption and the non-image area are compared with the case where the supplementary toner image is not formed in the non-image area in the width direction intersecting the rotation direction of the image holder. It is possible to suppress uneven supply of toner in the axial direction of .

In the image forming apparatus of the invention A 4, as compared with the case of forming no supplemental toner image by a transparent imaging means, the change in image quality due to the portion of the clear toner is transferred onto the recording medium of the supplementary toner image easily Can be suppressed.
In the image forming apparatus of the invention A 5 are, as compared with the case of not adjusted the amount of clear toner for forming the supplemental toner image by a transparent image forming means on the basis of the read information about the surface gloss of the recording medium, supplemented The change in surface gloss due to the transfer of a part of the colorless transparent toner of the toner image to the recording medium can be easily suppressed.

The image forming apparatus of the invention A 6, the amount of the formed pattern or toner forming amount and one or in response to both the information so as to interrupt the formation of supplemental toner image control or supplement the toner image formed continuously time of the toner image The amount of toner used to form the supplementary toner image can be suppressed as compared with the case where the change is not performed in the direction of reducing the amount of toner.

In the image forming apparatus of the invention A 7, as compared with the case of forming no supplemental toner image difficult to be visually recognized in a non-image area at the time of forming a toner image corresponding to image information, the non-image areas during operation to form an image Compared to the case where the toner image is not formed, the toner is applied to both the part of the latent image holder that comes into contact with the cleaning member of the first cleaning device and the part of the intermediate transfer body that comes into contact with the cleaning member of the second cleaning device. Can be supplied efficiently with little unevenness.
In the image forming apparatus of the invention A 8, as compared with the case of forming no supplemental toner image difficult to be visually recognized in a non-image area at the time of forming a toner image corresponding to image information, the first cleaning device in the latent image holding member Toner can be efficiently supplied to both the portion in contact with the cleaning member and the portion in contact with the cleaning member of the third cleaning device in the medium carrier with less unevenness.
The image forming apparatus of the invention A 9, even when using a medium arranged consecutively in a recording medium, as compared with the case where in operation of forming an image does not form a supplementary toner image on the non-image areas, the image rotating Toner can be efficiently supplied to the portion of the holder where the plate-shaped cleaning member comes into contact with less unevenness.

It is explanatory drawing which shows the structure of the image forming apparatus which concerns on Embodiment 1 and the like. It is explanatory drawing which shows the structure of the image forming part in the image forming apparatus of FIG. It is explanatory drawing which shows the structure of the image forming apparatus in the image forming part of FIG. It is explanatory drawing which shows the secondary transfer position in the image forming part of FIG. 2, the structure up to the belt cleaning apparatus, and the like. It is a block diagram which shows a part of the control system in the image forming apparatus of FIG. (A) is a graph showing an example of the relationship between the toner coverage and the density, and (b) is a graph showing an example of the relationship between the colorless and transparent toner coverage and the glossiness. Supplement It is explanatory drawing which shows the relationship of electric potentials at the time of forming a toner image. (A) is a developed explanatory view showing a state in which a normal toner image is formed in an image forming region on the image forming surface of the photosensitive drum, and (b) is a correction toner in a non-image region on the image forming surface of the photosensitive drum of (a). It is a development explanatory view which shows the state which formed the image. It is a development explanatory view which shows the state which formed by transferring the normal toner image and the supplementary toner image on the image holding surface of the intermediate transfer belt. (A) is a development explanatory view showing the state of the intermediate transfer belt after the secondary transfer, and (b) is a continuous paper after the normal toner image and the supplementary toner image are secondarily transferred from the intermediate transfer belt of (a). It is a development explanatory view which shows the state of. (A) is a development explanatory view showing an example of forming a supplementary toner image on the image forming surface of the photosensitive drum in a part of the non-image area, and (b) is a non-image of the supplementary toner image on the image forming surface of the photosensitive drum. It is a development explanatory view which shows an example of the case where it is formed in a state which is a part of a region and is distributed in the axial direction. It is explanatory drawing which shows the structure of the image forming apparatus which concerns on Embodiment 4. FIG. It is explanatory drawing which shows the structure of the image forming apparatus in the image forming apparatus of FIG. (A) is a developed explanatory view showing a state in which a normal toner image is formed in an image forming region (range of cut paper) on the image forming surface of the photosensitive drum, and (b) is an image forming surface of the photosensitive drum of (a). It is a development explanatory view which shows the state which formed the correction toner image in a non-image area. It is a development explanatory view which shows the state which formed by transferring the normal toner image and the supplementary toner image to the cut paper which holds and is carried on the holding surface of the paper transport belt. It is explanatory drawing which shows the structure of the belt cleaning device of the paper transport position in the image forming apparatus of FIG. 12 and the peripheral portion thereof. (A) is a development explanatory view showing a prior art showing a conventional technique of forming a toner image called a toner band in a portion of a gap between cut papers of an intermediate transfer belt, and (b) is the above of the intermediate transfer belt when continuous paper is used. It is a development explanatory view which shows the state which there is no part which becomes a gap.

Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as “embodiments”) will be described with reference to the drawings.

[Embodiment 1]
1 to 3 show an image forming apparatus and the like according to the first embodiment. FIG. 1 shows an overview of the image forming apparatus, FIG. 2 shows an outline of an image forming means in the image forming apparatus, and FIG. 3 shows a part of a configuration relating to control in the image forming apparatus.

<Overall configuration of image forming apparatus>
The image forming apparatus 1 according to the first embodiment is an apparatus for forming an image on a recording medium and a continuous paper 9 which is an example of a continuous medium, as conceptually shown in FIG. The image forming apparatus 1 includes a supply unit 10 that supplies continuous paper 9, an image forming unit 20 that forms various images on the continuous paper 9 supplied from the supply unit 10, and a continuous image forming unit 20 that is discharged from the image forming unit 20. It includes an accommodating portion 15 for accommodating the paper 9.

In the supply unit 10, a roll-shaped continuous paper 9 is detachably attached to the inside of the housing 11, and a feeding shaft 12 for feeding the continuous paper 9 is arranged. The feeding shaft 12 is rotationally driven by receiving power from a driving device (not shown). Further, the supply unit 10 has a tension applying transport device 13 for transporting the continuous paper 9 fed from the feeding shaft 12 to the inside of the housing 11 while applying tension by displacing the continuous paper 9 in the direction of the double-headed arrow, and a tension applying transport device 13. A guide roll 14 or the like for guiding the continuous paper 9 that has passed through the transport device 13 toward the image forming unit 20 is arranged. The direction indicated by the arrow C in FIG. 1 and the like is the transport direction of the continuous paper 9.

In the accommodating portion 15, a take-up shaft 17 or the like for winding the continuous paper 9 that has passed through the image forming portion 20 is arranged inside the housing 16. Further, the accommodating portion 15 has a guiding roll 18 and a guiding roll 18 for guiding the continuous paper 9 discharged from the image forming portion 20 into the housing 16 of the accommodating portion 15 inside the housing 16. A tension applying transfer device 19 or the like is arranged to transfer the continuous paper 9 guided through the paper 9 toward the take-up shaft 17 while applying tension by displacing the continuous paper 9 in the direction of the double-headed arrow. The take-up shaft 17 is a shaft having a structure that can be removed after winding the continuous paper 9 in a roll shape, and is rotationally driven by receiving power from a drive device (not shown).

As the continuous paper 9, for example, a strip-shaped continuous long member made of paper such as high-quality paper or coated paper or a material such as synthetic resin such as polypropylene is used. Further, as the continuous paper 9, for example, a continuous label paper having a structure in which a surface base material (image forming surface) is provided on a release paper via an adhesive layer is also applied.

As shown in FIGS. 1 and 2, the image forming unit 20 is formed by an image forming device 21 for forming a toner image composed of toner as a developer and an image forming device 21 inside the housing 200. An intermediate transfer device 30 that holds the toner image to be transferred and transfers it to a secondary transfer position that is finally transferred to the continuous paper 9, a fixing device 40 that fixes the toner image transferred to the continuous paper 9, and the like. It is arranged and configured. The housing 200 is provided with, for example, an introduction port 201 for introducing the continuous paper 9 through the side surface portion facing the supply unit 10, and an discharge port for passing the continuous paper 9 through the side surface portion facing the accommodating portion 15. 202 is provided.

The image-forming device 21 is a four image-forming device 21Y, 21M that exclusively forms a toner image of any one of the four colors of yellow (Y), magenta (M), cyan (C), and black (K). , 21C, 21K.
As shown in FIGS. 2 and 3, each of the image forming apparatus 21 (Y, M, C, K) has a photosensitive drum 22 which is an example of a latent image holder that is rotationally driven in a required direction. A charging device 23, an exposure device 24, a developing device 25 (Y, M, C, K), a primary transfer device 26, a drum cleaning device 27, a static eliminator 28, etc. are arranged around each photosensitive drum 22. Has been done. In particular, the charging device 23, the exposure device 24, and the developing device 25 (Y, M, C, K) in the image forming device 21 (Y, M, C, K) constitute an image forming means for actually forming a toner image. ing.

Of these, the photosensitive drum 22 is a drum-shaped photoconductor in which an image-forming surface having a photodielectric layer (photosensitive layer) made of a photosensitive material is formed on the peripheral surface of a cylindrical or columnar conductive base material to be grounded. , It is provided so as to receive rotational power from a rotational drive device (not shown) and rotationally drive in the direction indicated by the arrow A.
The charging device 23 is a device that charges the image forming surface of the photosensitive drum 22 by receiving a charging voltage. The exposure apparatus 24 is an apparatus for forming an electrostatic latent image by exposing light based on image information (signal) to the image forming surface of the photosensitive drum 22 after charging. Image information connected / input from the outside of the image forming apparatus 1 via a communication means or the like is input to the exposure apparatus 24 as an image signal after necessary image processing or the like is performed.

The developing apparatus 25 (Y, M, C, K) develops an electrostatic latent image of each color component formed on the image forming surface of the photosensitive drum 22 with a toner of the corresponding color of the developing agent to form a toner image. It is a device to do. Further, the developing apparatus 25 (Y, M, C, K) has a developing roll 251 or the like that receives a developing voltage supply or the like and conveys a developing agent to a developing region facing the photosensitive drum 21. The primary transfer device 26 is a device that receives the supply of the primary transfer voltage and first transfers the toner image formed on the image forming surface of the photosensitive drum 22 to the intermediate transfer device 30 (the outer peripheral surface of the intermediate transfer belt 31).

As shown in FIGS. 2 and 3, the drum cleaning device 27 is a device that removes and cleans unnecessary substances such as toner that stay on the image forming surface of the photosensitive drum 22 and adhere to it. Further, the drum cleaning device 27 includes a plate-shaped cleaning member (elastic blade or the like) 27a that brings the tip corner portion into contact with the image forming surface of the photosensitive drum 22 inside the housing, and toner or the like removed by the cleaning member 27a. A delivery member 27b or the like is arranged to send the unnecessary material to a collection unit (not shown). The static eliminator 28 is a device that removes unnecessary charges remaining on the image forming surface of the photosensitive drum 21.

The intermediate transfer device 30 is arranged so as to rotate in a required direction while passing through each of the primary transfer positions facing the primary transfer device 26 of the photosensitive drum 22 in the four image drawing devices 21 (Y, M, C, K). It includes an intermediate transfer belt 31 which is an example of an image holder. Further, in the intermediate transfer device 30, a secondary transfer device 35, a belt cleaning device 37, and the like are arranged around the intermediate transfer belt 31.

The intermediate transfer belt 31 is an endless belt member having an image holding surface that holds a toner image by electrostatic action, and is rotatably supported by being hung on a plurality of support rolls 32a to 32f.
The support roll 32a is a drive roll, the support roll 32b is a surface driven roll that holds the primary transfer surface of the intermediate transfer belt 31 in cooperation with the drive roll 32a, and the support roll 32c applies tension to the intermediate transfer belt 31. As the tension applying roll, the support roll 32d is a surfaced driven roll for surfaced before the secondary transfer of the intermediate transfer belt 31, the support roll 32e is a secondary transfer backup roll, and the support roll 32f is a cleaning backup roll. It is configured.
The intermediate transfer belt 31 is rotationally driven in the direction indicated by the arrow B by receiving rotational power from a rotational drive device (not shown) from the drive roll 32a.

The secondary transfer device 35 presses the continuous paper 9 against the outer peripheral surface portion of the intermediate transfer belt 31 supported by the secondary transfer backup roll 32e, and transfers the toner image on the intermediate transfer belt 31 to the continuous paper 9. A secondary transfer roll 36, which is an example of a transfer member, is provided.
Further, in the secondary transfer device 35, as illustrated by the double-headed arrow in FIG. 2, the secondary transfer roll 36 in contact with the outer peripheral surface of the intermediate transfer belt 31 comes into contact with the outer peripheral surface of the intermediate transfer belt 31 at a time when the image forming operation is not performed. , The intermediate transfer belt 31 is configured to move to a position separated from the outer peripheral surface by the action of a contact separation mechanism (not shown). In this case, the continuous paper 9 is kept in a state of being supported by the secondary transfer roll 36 and separated from the outer peripheral surface of the intermediate transfer belt 31.

As shown in FIGS. 2 and 4, the belt cleaning device 37 is a device that removes and cleans unnecessary substances such as toner that stay on the image holding surface of the intermediate transfer belt 31 and adhere to it. Further, the belt cleaning device 37 includes a plate-shaped cleaning member (elastic blade or the like) 37a that brings the tip corner portion into contact with the image holding surface of the intermediate transfer belt 31 and an image holding surface of the intermediate transfer belt 31 inside the housing. A rotary cleaning brush 37b that rotates while in contact with the cleaning member 37a, and a delivery member 37c that sends out unnecessary objects such as toner removed by the cleaning member 37a and the rotary cleaning brush 37b toward a collection unit (not shown) are arranged.

The fixing device 40 is rotationally driven in a required direction and heated by a heating means to maintain the surface temperature at a required temperature inside a housing provided with an introduction port and a discharge port for the continuous paper 9. A roll form, a belt form, a belt-put form, etc. The rotating body 43 for pressurization and the like are installed and configured. In the fixing device 40, the portion where the heating rotating body 42 and the pressing rotating body 43 come into contact is configured as a fixing processing unit in which the continuous paper 9 holding the toner image is introduced and the fixing treatment (pressurization and heating) is performed. Has been done.
Further, in the fixing device 40, when the image forming operation is not performed or the like, the pressurizing rotating body 43 in contact with the heating rotating body 42 is affected by the action of a contact separation mechanism (not shown) to cause the heating rotating body 42. It is configured to move away from. In this case, the continuous paper 9 is kept in a state of being supported by the pressurizing rotating body 43 and separated from the heating rotating body 42.

Further, in the image forming unit 20, as shown in FIGS. 1 and 2, the introduction port 201 of the housing 200 and the secondary transfer position in the intermediate transfer device 30 (intermediate transfer belt 31 and secondary transfer position 35 face each other). Belt-type transfer devices 29A and 29B for auxiliary feeding the continuous paper 9 are arranged between the secondary transfer position and the fixing device 40.
Further, in the image forming unit 20, an input unit 51 for inputting instructions and conditions related to the operation of the image forming apparatus 1 and a display unit 52 for displaying various information such as operating conditions and states are displayed outside the housing 200. The operation display device 50 having the above is arranged. Further, inside the housing 200, a central control means 60 and the like that collectively control the operation of the entire image forming apparatus 1 (each of the above-mentioned apparatus and the like) are also arranged.

<Basic image formation operation>
In this image forming apparatus 1, the basic image forming operation described below is performed. Here, a case of forming a multicolor image composed by combining toner images of four colors (Y, M, C, K), a so-called full-color image, will be described as an example.

When the central control means 60 receives a command requesting an image forming operation, the image forming apparatus 1 has substantially the same toner image in the four image forming apparatus 21 (Y, M, C, K) in the image forming unit 20. Formation begins.

First, in each image forming device 21 (Y, M, C, K), each photosensitive drum 22 starts to rotate and drive in the direction indicated by the arrow A, and each charging device 23 operates by receiving the supply of the charging voltage. , The image forming surface of each photosensitive drum 22 is charged so as to have a required polarity (for example, negative polarity) and a surface potential.
Subsequently, the exposure apparatus 24 operates by receiving an image signal decomposed into four color components (Y, M, C, K) based on image information input from the outside, thereby charging each photosensitive drum 22. Writing exposure corresponding to the image signal is performed on the formed image forming surface. As a result, an electrostatic latent image of each color component composed of a predetermined potential is individually formed on the image forming surface of each photosensitive drum 22.
Subsequently, each developing device 25 (Y, M, C, K) receives the supply of the developing voltage and is driven to rotate to operate, so that the electrostatic of each color component formed on the image forming surface of each photosensitive drum 22 is electrostatic. Toner of the corresponding color is supplied to the latent image and electrostatically adhered. As a result, toner images of four colors (Y, M, C, K) are individually formed on the image forming surface of each photosensitive drum 22.

Next, the toner images of each color formed on the photosensitive drum 22 of each image forming apparatus 21 (Y, M, C, K) are relayed by the intermediate transfer apparatus 30 in the image forming apparatus 20 and transferred to the continuous paper 9. NS.

First, in each image forming apparatus 21 (Y, M, C, K), each primary transfer in which the toner images of each color formed on the photosensitive drums 22 face the intermediate transfer belt 31 by the rotation of the photosensitive drums 22. It is transported to the position. The toner images of each color are static electricity with respect to the outer peripheral surface of the intermediate transfer belt 31 due to the action of the transfer electric field formed between the primary transfer devices 26 and the photosensitive drums 22 by receiving the supply of the primary transfer voltage. It is electrically primaryly transferred. Further, the image forming surface of each photosensitive drum 22 after the primary transfer is cleaned by each drum cleaning device 27 removing unnecessary substances such as toner, and then the remaining charge is removed by the static eliminator 28. Prepare for the toner image forming process.

Subsequently, in the intermediate transfer device 30, the toner image primary transferred to the outer peripheral surface of the intermediate transfer belt 31 is rotated in the direction indicated by the arrow B of the intermediate transfer belt 31 to cause the secondary transfer roll 36 of the secondary transfer device 35. It is transported to the secondary transfer position facing the.
On the other hand, the continuous paper 9 in the supply unit 10 is tensioned from the feeding shaft 12 mainly by receiving the secondary transfer position of the intermediate transfer device 30 in the image forming unit 20 and the conveying force in the fixing processing unit of the fixing device 40. After being fed out by a required length via the transfer device 13 and the guide roll 14 and introduced into the image forming unit 20, the transfer device 29A is conveyed so as to reach the secondary transfer position.

As a result, the toner image on the intermediate transfer belt 31 is transferred between the secondary transfer roll 36 and the secondary transfer backup roll 32 when the secondary transfer device 35 receives the supply of the secondary transfer voltage at the secondary transfer position. Due to the action of the formed transfer electric field, the secondary transfer roll 36 electrostatically transfers the secondary transfer to the continuous paper 9 pressed against the outer peripheral surface of the intermediate transfer belt 31. The outer peripheral surface of the intermediate transfer belt 31 after the secondary transfer or the like is cleaned by the belt cleaning device 37 removing unnecessary substances such as toner.

Next, the continuous paper 9 on which the toner image is secondarily transferred is peeled off from the intermediate transfer belt 31 and introduced into the fixing device 40 via the transfer device 29B.
In the fixing device 40, the continuous paper 9 is introduced into the fixing processing section between the heating rotating body 42 and the pressing rotating body 43 and conveyed so as to pass therethrough, and is heated under pressure when passing therethrough. As a result, the toner image constituting the toner image is melted and fixed on the continuous paper 9.
Finally, the continuous paper 9 on which the image is formed by the completion of fixing receives the conveying force by the winding shaft 17 of the accommodating portion 15 and reaches the accommodating portion 15 via the induction roll 18 and the tension applying conveying device 19. After being conveyed, it is wound around the take-up shaft 17.

By executing the above image forming operation, a full-color image formed by combining four-color toner images is formed on one side of the continuous paper 9.

<Supplementary configuration related to the operation of forming a toner image>
Further, as shown in FIGS. 3 to 5, 8 and the like, the image forming apparatus 1 is a cleaning member of the drum cleaning device 27 in the photosensitive drum 22 of each image forming apparatus 21 (Y, M, C, K). Since toner is supplied to the portion 22s in contact with the 27a and the portion 31s in contact with the cleaning member 37a of the belt cleaning device 37 in the intermediate transfer belt 31 of the intermediate transfer device 30, the toner is visually recognized during the image forming operation. The control means 61 for executing the operation of forming the supplementary toner image Ts, which is difficult to be generated, is provided.

Here, the supplemental toner Ts is different from the normal toner image Tg formed according to the image information, and the toner (strictly, not transferred) is applied to the respective portions 22s and 31s in contact with the cleaning members 27a and 37a. It is a toner image formed to supplement the remaining toner).
Therefore, the supplementary toner image Ts is obtained by the image forming apparatus 21 (Y, M, C, K) according to the image information, as illustrated in the schematic view in which the image forming surface of the photosensitive drum 22 is developed in FIG. When a toner image Tg is formed in an image forming region D having a fixed size, it is formed in a non-image region NE in which the toner image Tg is not formed in the image forming region D.
The non-image area NE is, in principle, an area of the image forming area D excluding the image area GE on which the toner image Tg is formed, in other words, when the image area GE of the image forming area D is inverted. It is an area obtained in. However, in reality, the image quality guarantee area YE set in the photosensitive drum 22 or the like that is outside the image formation region D, or the width direction (axial direction) that intersects the rotation direction A of the photosensitive drum 22 from the image quality guarantee area YE. The left and right ends Ee (where the toner image can be formed) that come off in E can also be included. That is, it is desirable that the non-image area NE is a region having a width corresponding to at least a length along the width direction E of the cleaning member 27a of the drum cleaning device 27, except for the portion where the toner image cannot be formed.

Further, "hard to see" in the supplementary toner image Ts means that the supplementary toner image Ts is hard to be noticed by the naked eye at the stage when the supplementary toner image Ts is transferred to the continuous paper 9 which is the final transfer destination and fixed. Further, at the stage where the supplementary toner image Ts is fixed, as will be described later, the image quality and surface gloss of the image obtained after the normal toner image Tg is transferred to a recording medium such as continuous paper 9 and fixed are adversely affected. It is also a property that does not reach.
Therefore, the supplementary toner image Ts has a thinner layer thickness or a lower toner coverage than the layer thickness of the normal toner image Tg or the toner coverage per unit area of the formation region thereof. Will be formed.

Regarding the coverage, there is a relationship as illustrated in FIG. 6A with the density of the image. The results shown in the figure show the relationship between the toner coverage and the density of the toner image when an image made of black K toner is formed on recording paper.
From the result of FIG. 6A, when the density of the toner image when the toner coverage is 0%, that is, the density of the recording paper is about 0.07, when the toner coverage exceeds 5%, it is different from the recording paper. Although a density difference begins to occur, it can be seen that if the toner coverage is within 5%, there is no density difference with the recording paper, and an inconspicuous (hard to see) state can be obtained.

The control means 61 is composed of, for example, an arithmetic processing unit, a storage element, a storage device, an input / output device, and the like. Further, the control means 61 executes a required control operation based on a program and data stored in the storage element (ROM) or the like. In particular, the control means 1 in the first embodiment is configured to be able to execute the above-mentioned supplementary toner image Ts forming operation. Further, although the control means 61 is configured as a part of the central control means 60, it may be configured as an independent means.

Further, as shown in FIG. 5, the control means 61 includes an image processing unit 55 that performs necessary image processing on image information input from the outside of the image forming apparatus 1, and an exposure driving unit 56 that drives the exposure device 24. Power supply means (feeding unit) 57 and operation display device 50 that supply the charging voltage to the charging device 23, the developing voltage to the developing device 25, and the primary or secondary transfer voltage to the primary transfer device 26 and the secondary transfer device 35, respectively. It is connected to the display unit 52 and the like, and transmits a control signal necessary for performing an operation such as a confirmation operation to them. Further, the control means 61 is connected to a communication unit 53 that communicates information with an external device or the like, an input unit 51 of the operation display device 50, or the like, thereby obtaining information necessary for control operation. There is.

Further, when the control means 61 executes the image forming operation, in addition to transmitting the image signal of the normal toner image Tg formed according to the image information from the image processing unit 55 to the exposure driving unit 56, the control means 61 supplements. It is configured to transmit an image signal of the toner image Ts.

The image forming operation including the formation of the supplementary toner image Ts is different from the case where only the normal toner image Tg is formed in that the formation of the supplementary toner image Ts is added, but the normal image is obtained for other image forming conditions. It is carried out by applying the same conditions as when forming.

Further, regarding the formation of the supplementary toner image Ts in the image forming apparatus 1 provided with the plurality of image forming apparatus 21 (Y, M, C, K) as in the first embodiment, all of the image forming apparatus 21 thereof. From the viewpoint that the cleaning device 27 is equipped, it is preferable to perform the image forming device 21 (Y, M, C, K) of all colors. On the other hand, for example, when the supplementary toner image Ts is transferred to the continuous paper 9 of the final transfer destination and fixed, it is possible to avoid inducing problems such as deterioration of the image quality of the image composed of the normal toner image Tg. From this point of view, it is desirable to limit the operation to a part of the (color) image forming apparatus 21.

Supplement When forming the toner image Ts, for example, in the image processing unit 55, the image area GE in which the normal toner image Tg is formed is determined for the image forming region D determined according to the image information to be formed. After the non-image area NE is determined by inversion processing or the like in accordance with the above, an image pattern of the supplementary toner image Ts formed in the entire area or a part of the non-image area NE is generated. When forming a part of the non-image area NE (see, for example, the formation example of FIG. 11), a rule for determining a part thereof is created in advance, and an image pattern of the supplementary toner image Ts is created based on the rule. Generate.

Further, as illustrated in FIG. 7, the formation of the supplementary toner image Ts is such that the potential Vis of the electrostatic latent image EIs of the supplementary toner image Ts formed by the exposure apparatus 24 is electrostatically latent in the normal toner image Tg. This is performed by setting the potential at which toner is less likely to adhere than the potential Vig of the image EIg.
Specifically, when the image forming surface of the photosensitive drum 21 is charged to a negatively polar charging potential Vh and then reverse development is performed with a negatively charged toner by applying a predetermined development bias potential Vd, a supplementary toner image is obtained. The potential Vis of the electrostatic latent image EIs of Ts is set to a potential closer to the development bias potential Vd than the potential Vig of the electrostatic latent image EIg in the normal toner image Tg.

Further, as will be described later, when the supplementary toner image Ts is first transferred to the intermediate transfer belt 31 after being formed on the photosensitive drum 22, a part of the toner (Ts1) is mainly minute at the primary transfer position. Due to the influence of the electric discharge generated in the voids, the polarity is opposite to that of the normal polarity, so that the primary transfer is not performed and remains on the photosensitive drum 22. Further, in the supplementary toner image Ts that is primarily transferred from the photosensitive drum 22 to the intermediate transfer belt 31 and held, when the supplementary toner image Ts is secondarily transferred to the continuous paper 9, a part of the toner (Ts2) is mainly at the secondary transfer position. Due to the influence of the electric discharge generated in the minute voids in the above, the toner is charged to a polarity opposite to the normal polarity, so that it remains on the intermediate transfer belt 31 without being secondarily transferred.

<Supplementary toner image formation operation and its action effect>
When the image forming operation is performed, the image forming apparatus 1 has any of four colors on the photosensitive drum 22 in each image forming apparatus 21 (Y, M, C, K) as illustrated in FIG. 8 (a). In addition to forming a normal toner image Tg having the same color in the image forming region D, as illustrated in FIG. 8B, a non-image region in which the normal toner image Tg is not formed. A supplementary toner image Ts is formed on the NE.

The non-image area NE on which the supplementary toner image Ts illustrated in FIG. 8B is formed is the image area GE on which the normal toner image Tg is formed in the image-forming area on the image-forming surface of the photosensitive drum 22. It is an area to be excluded. Specifically, the region excluding the image region GE of the image forming region D, the region other than the image forming region D of the image quality effective region YE, and the end region Ee of the image forming enableable region on both sides of the image quality effective region YE are combined. Area.
Further, in the first embodiment, the supplementary toner images Ts are formed in the four image forming devices 21 (Y, M, C, K).

The formation of the normal toner image Tg and the supplementary toner image Ts is performed in the same manner as in the case of the image forming step of the image forming operation described above.
First, in each image forming device 21 (Y, M, C, K), the image forming surface of the photosensitive drum 22 is charged to a required charging potential Vh by the charging device 23, and then transmitted from the image processing unit 55 by the control means 61. Based on the image signal of the normal toner image Tg and the image signal of the supplementary toner image Ts, the exposure apparatus 24 forms electrostatic latent images Elg and Els composed of the required latent image potentials Vig and Vis (FIG. 7). reference).
Subsequently, in each image forming apparatus 21 (Y, M, C, K), the electrostatic latent images Elg and Els formed on the image forming surface of the photosensitive drum 22 are the developing apparatus 25 (Y, M, C) having a predetermined color. , K). As a result, the normal toner image Tg and the supplementary toner image Ts illustrated in FIG. 8B are formed on the image forming surface of the photosensitive drum 22, respectively.

Next, at the primary transfer position of each image forming apparatus 21 (Y, M, C, K), the normal toner image Tg and the supplementary toner image Ts on the image forming surface of each photosensitive drum 22 are primary to the intermediate transfer belt 31. Transferred.
At this time, as illustrated in FIG. 3, some toners Ts1 constituting the supplementary toner image Ts are not primarily transferred due to the principle of being charged in the opposite polarity as described above, and remain on the image forming surface of the photosensitive drum 22. Further, at this time, some of the toners constituting the normal toner image Tg are not primary transferred and remain on the image forming surface of the photosensitive drum 22 according to the principle of being charged in the opposite polarity as described above.
Then, at this time, the toner Ts1 remaining without the primary transfer of the supplementary toner image Ts in each image forming apparatus 21 (Y, M, C, K) is together with the toner remaining without the primary transfer of the normal toner image Tg. It is conveyed by the rotation of the photosensitive drum 22, and finally reaches the portion 22s on the image forming surface of the photosensitive drum 22 where the cleaning member 27a of each drum cleaning device 27 comes into contact with each other.

As a result, in each image forming device 21 (Y, M, C, K), the portion (tip corner portion) of the cleaning member 27a of each drum cleaning device 27 that comes into contact with the image forming surface of the photosensitive drum 22 reaches the above. The toner (Ts1) (including the external additive added to the toner particles) functions as a lubricant, so that its wear and abnormal noise are suppressed.
Further, by forming the supplementary toner image Ts in addition to the normal toner image Tg, the portion 22s in contact with the plate-shaped cleaning member 27a in the photosensitive drum 22 is generated from the normal toner image Tg in the image area GE. In addition to the toner remaining in the primary transfer, the toner (Ts1) remaining in the primary transfer generated from the supplementary toner image Ts in the non-image area NE is also supplied so as to be supplemented. As a result, the toner can be efficiently supplied to the contact portion 22s with less unevenness as compared with the case where only the normal toner image Tg is formed and the supplementary toner image Ts is not formed.

Next, at the secondary transfer position in the intermediate transfer device 30, as shown in FIG. 9, the normal toner image Tg and the supplementary toner image Ts primary transferred to the intermediate transfer belt 31 are secondarily transferred to the continuous paper 9. ..
At this time, as illustrated in FIG. 4, some toners Ts2 constituting the supplementary toner image Ts are not secondarily transferred due to the principle of being charged in the opposite polarity as described above, and remain on the image holding surface of the intermediate transfer belt 31. At this time, as illustrated in FIG. 10A, some toners (Tg2) constituting the normal toner image Tg are also secondarily transferred by the same principle as the above-mentioned principle of being charged in the opposite polarity. It remains on the image holding surface of the intermediate transfer belt 31.
At this time, the toner Ts2 remaining without secondary transfer of the supplementary toner image Ts in the intermediate transfer device 30 is conveyed together with the toner Tg2 remaining without secondary transfer of the normal toner image Tg by the rotation of the intermediate transfer belt 31. Finally, the cleaning member 37a of the belt cleaning device 37 on the image holding surface of the intermediate transfer belt 31 reaches the contact portion 31s.

As a result, in the intermediate transfer device 30, the toner (Ts2) that has reached the portion (tip corner portion) of the cleaning member 37a of the belt cleaning device 37 that contacts the image holding surface of the intermediate transfer belt 31 functions as a lubricant. By doing so, the wear and the generation of abnormal noise are suppressed.
Also in this case, by forming the supplementary toner image Ts in addition to the normal toner image Tg, the normal toner image Tg in the image area GE is contacted with the portion 31s in which the plate-shaped cleaning member 37a of the intermediate transfer belt 31 comes into contact. In addition to the secondary transfer residual toner (Tg2) generated from, the secondary transfer residual toner (Ts2) generated from the supplementary toner image Ts in the non-image area NE is supplied so as to be supplemented. As a result, the toner can be efficiently supplied to the contact portion 31s with less unevenness as compared with the case where only the normal toner image Tg is formed and the supplementary toner image Ts is not formed.

Then, as shown in FIG. 10B, a normal toner image Tg is secondarily transferred to one side of the continuous paper 9 output by this image forming operation. The toner image Tg is then fixed by the fixing device 40 to become a formal image.
At this time, the supplementary toner image (Ts) is also secondarily transferred to one side of the continuous paper 9 except for a part of the toner (Ts2) which is not secondarily transferred, and finally fixed by the fixing device 40. However, the supplementary toner image (Ts) after being fixed on the continuous paper 9 cannot be confirmed with the naked eye because the supplementary toner image itself is formed so as to be difficult to see.

Further, in the image forming apparatus 1 adopting this intermediate transfer method, since the continuous paper 9 is used as the recording medium, there are the following advantages.

That is, when a so-called cut paper cut to a predetermined size is used as the recording medium, the cut paper 90 is placed on the image holding surface at the secondary transfer position of the intermediate transfer belt 31 as illustrated in FIG. 17 (a). There is a part that becomes a gap (paper gap) S1 in which is not present. Therefore, when the toner is supplied to the portion 31s in contact with the cleaning member 37a of the belt cleaning device 37, for example, the gap S1 on the image holding surface of the intermediate transfer belt 31 is adapted to the shape and position of the gap. A band-shaped toner image (so-called toner band) TB may be formed by the image forming apparatus 21 and first transferred to the intermediate transfer belt 31, and then sent as it is to the contact portion 31s without secondary transfer. As a result, a relatively large amount of toner can be fed to the contacted portion 31s, although it is intermittent and uneven.
On the other hand, when the continuous paper 9 is used as the recording medium, as illustrated in FIG. 17B, for example, the continuous paper 9 is always present on the image holding surface of the intermediate transfer belt 31 at the secondary transfer position without any gap. Therefore, there is no portion that becomes the gap S1 as in the case of using the cut paper 90. Therefore, it is not possible to form the toner band TB as in the case of using the cut paper 90, and it is not possible to supply the toner to the contact portion 31s.

In this regard, in the image forming apparatus 1 for forming the supplementary toner image Ts, as described above, even when the continuous paper 9 is used, the toner is applied to the portion 31s of the intermediate transfer belt 31 where the cleaning member 37a comes into contact. Can be efficiently supplied with little unevenness.
In FIG. 17, reference numeral L1 is the length dimension of the intermediate transfer belt 31 of the cut paper 90 in the rotation direction B, reference numeral W1 is the width dimension of the cut paper 90 in the width direction E, and reference numeral W2 is the width dimension of the continuous paper 9. Each is shown.

<Modified example of the first embodiment>
In the first embodiment, as illustrated in FIG. 2, a first color reading means (color density sensor) 71A for reading the color of the continuous paper 9 and the continuous paper 9 are inside the housing 200 of the image forming unit 20. A second reading means (color density sensor) 71B for reading the density of the image formed in the above is provided, and then the control means 61 relates to the color of the continuous paper 9 obtained from the color reading means 71A and 71B and the density of the image. The image forming apparatus 21 (Y, M, C, K) may be configured to adjust one or both of the color of the toner and the amount used thereof when forming the supplementary toner image Ts based on the read information.

In this case, the first color reading means 71A for reading the color of the continuous paper 9 may be arranged at least at a position upstream of the secondary transfer position of the intermediate transfer device 30 in the transport direction C of the continuous paper 9. In some cases, it may be arranged in the housing 11 of the supply unit 10. Further, the second reading means 71B for reading the density of the image may be arranged at least at a position downstream of the fixing device 40 in the transport direction C in the transport direction C, but in some cases, the housing 16 of the accommodating portion 15 may be arranged. You may place it inside. The first color reading means 71A and the second color reading means 71B are connected to the control means 61 as shown in FIG.

Further, in this case, for the adjustment of the toner color and the amount of the toner used when forming the supplementary toner image Ts by the control means 61, for example, as illustrated in FIG. 5, an adjustment determination unit 75 independent of the control means 61 is provided. After the adjustment determination unit 75 determines the toner color and its usage amount, the determined information is reflected in the control operation of the image forming apparatus 21 (Y, M, C, K) by the control means 61. can do. The adjustment determination unit 75 is connected to the control means 61 so that the detection information obtained by the color reading means 71A and 71B can be obtained.

In the adjustment determination unit 75, for example, when the color of the continuous paper 9 is yellow, the first color reading means 71A reads that the color of the continuous paper 9 is yellow (Y), and the second color reading means 71B reads the image. It is assumed that the result is read in which the density (color tone) of is influenced by colors other than yellow (M, C, K).

In this case, when the supplementary toner image Ts is formed, the adjustment determination unit 75 reduces the amount of toner used in the image forming apparatus 21 (M, C, K) that receives the toner of the affected color, while reducing the amount of toner used. It is determined that it is preferable to make adjustments so as to increase the amount of yellow (Y) toner used in the image forming apparatus 21Y that forms a yellow toner image. In this case, the supplementary toner image Ts composed of the yellow color (Y) toner is formed, but the yellow color supplementary toner image Ts uses toners of other colors (M, C, K). Compared with the supplementary toner image Ts formed in the above process, the toner image can be made more difficult to see at the stage of being recorded on a recording medium such as continuous paper 9.
Further, in the adjustment determination unit 75, when the image forming operation is performed using the continuous paper 9 of this color, the measurement information of the coverage rate per unit area of the supplementary toner image Ts and the density of the image is recorded. Then, for example, data showing the relationship between the toner coverage and the concentration illustrated in FIG. 6A is created. By using this data, when forming the supplementary toner image Ts on the continuous paper 9 of the above colors, it is determined to what value the toner coverage ratio, which is difficult to see, is allowed, and the result is controlled later. It can be reflected in the operation.

[Embodiment 2]
As the image forming apparatus according to the second embodiment, as shown by the two-point chain line in FIGS. 1 and 2, a transparent image forming apparatus 21H for forming a transparent toner image made of colorless transparent toner is added, and the control means 61 is used to add the transparent image forming apparatus 21H. It has the same configuration as the image forming apparatus 1 according to the first embodiment except that the transparent image forming apparatus 21H is configured to control the formation of the supplementary toner image Ts.

The formation of the supplementary toner image Ts by the transparent image forming apparatus 21H is different in that the toner used is changed to the transparent colorless toner, but the supplementary toner image Ts of four colors (colored) in the first embodiment is formed. It is done in the same way as the above conditions.

However, the supplementary toner image Ts made of transparent colorless toner at this time does not have a possibility of adversely affecting the color tone of the image made of normal toner image Tg as compared with the case of the supplementary toner image Ts of four colors (colored). The surface gloss of the continuous paper 9 after the image is formed may differ (actually, the glossiness increases) depending on the magnitude of the toner coverage.

In this respect, the toner coverage when the transparent colorless toner is used has a relationship with the glossiness as illustrated in FIG. 6 (b). The results shown in the figure show the relationship between the toner coverage and the surface gloss of the recording medium on which the image is formed when an image made of transparent colorless toner is formed on a recording medium such as continuous paper 9. The glossiness at this time was measured using a Byk Gardener Micro-Tri-Gloss gloss meter under the condition of a measurement angle of 60 ° with respect to a black background.
From the result of FIG. 6B, when the density when the toner coverage is 0%, that is, when the glossiness of the recording medium is about 5, when the toner coverage exceeds 20%, the glossiness difference from the recording medium becomes large. Although it starts to occur, it can be seen that when the toner coverage is within 20%, there is no difference in glossiness from the recording medium, and a state in which the difference in surface gloss is inconspicuous (hard to see) can be obtained.

<Supplementary toner image formation operation and its action effect>
When the image forming operation is performed, the image forming apparatus 1 has each image forming device 21 (as illustrated in FIG. 8A), substantially in the same manner as in the case of the supplementary toner image forming operation in the first embodiment. In Y, M, C, K), in addition to forming a normal toner image Tg composed of any of the four colors on the photosensitive drum 22 in the image forming region D, it is illustrated in FIG. 8 (b). As described above, in the transparent image forming apparatus 21H, the supplementary toner image Ts made of colorless transparent toner is formed in the non-image area NE on the image forming surface of the photosensitive drum 11.

First, when the image forming operation is started, in the four-color image forming apparatus 21 (Y, M, C, K), the image forming surface (image area GE) of each photosensitive drum 22 is shown in FIG. 8 (b). The usual toner image Tg exemplified in the above is formed. Further, in the transparent image forming apparatus 21H, a supplementary toner image Ts made of the colorless transparent toner exemplified in FIG. 8B is formed on the image forming surface (non-image area NE) of the photosensitive drum 22.

Next, at the primary transfer position of the image forming apparatus 21 (Y, M, C, K), the normal toner image Tg on the image forming surface of each photosensitive drum 22 is first transferred to the intermediate transfer belt 31 to create a transparent image. In the device 21H, the supplementary toner image Ts is primarily transferred to the intermediate transfer belt 31.
At this time, as illustrated in FIG. 3, in the transparent image forming apparatus 21H, a part of the colorless transparent toner Ts1 constituting the supplementary toner image Ts is not primarily transferred due to the principle of being charged in the opposite polarity as described above. It remains on the image forming surface of the photosensitive drum 22. At this time, also in the image forming apparatus 21 (Y, M, C, K), some toners (Tg1) constituting the normal toner image Tg are also charged in the opposite polarity as described above. It remains on the image forming surface of the photosensitive drum 22 without being primary transferred.
Then, at this time, the colorless transparent toner Ts1 remaining without the primary transfer of the supplementary toner image Ts in the transparent image forming apparatus 21H is conveyed together with the toner remaining without the primary transfer of the normal toner image Tg by the rotation of each photosensitive drum 22. Then, the cleaning member 27a of the drum cleaning device 27 reaches the contact portion 22s on the image forming surface of the photosensitive drum 22.

As a result, particularly in the transparent image forming apparatus 21H, the colorless transparent toner (Ts1) that has reached the portion of the cleaning member 27a of the drum cleaning apparatus 27 that comes into contact with the image forming surface of the photosensitive drum 22 functions as a lubricant. As a result, the wear and the generation of abnormal noise are suppressed. Further, in the image drawing device 21 (Y, M, C, K), the portion of the cleaning member 27a of each drum cleaning device 27 that comes into contact with the image forming surface of the photosensitive drum 22 is covered with a small amount of toner of each color that has reached the above. By functioning as a lubricant, its wear and generation of abnormal noise are suppressed to some extent.

Next, at the secondary transfer position in the intermediate transfer device 30, as shown in FIG. 9, the normal toner image Tg and the supplementary toner image Ts primary transferred to the intermediate transfer belt 31 are secondarily transferred to the continuous paper 9. ..
At this time, as illustrated in FIG. 4, a part of the colorless transparent toner Ts2 constituting the supplementary toner image Ts primaryly transferred to the non-image area NE is secondarily transferred by the principle of being charged in the opposite polarity as described above. It remains on the image holding surface of the intermediate transfer belt 31. At this time, as illustrated in FIG. 10A, some toners (Tg2) constituting the normal toner image Tg are also secondarily transferred by the same principle as the above-mentioned principle of being charged in the opposite polarity. It remains on the image holding surface of the intermediate transfer belt 31.
Then, at this time, the colorless transparent toner Ts2 remaining without the secondary transfer of the supplementary toner image Ts in the intermediate transfer device 30 rotates the intermediate transfer belt 31 together with the toner Tg2 remaining without the secondary transfer of the normal toner image Tg. Finally, the cleaning member 37a of the belt cleaning device 37 on the image holding surface of the intermediate transfer belt 31 reaches the contact portion 31s.

As a result, in the intermediate transfer device 30, the colorless transparent toner (Ts2) that has reached the portion of the cleaning member 37a of the belt cleaning device 37 that comes into contact with the image holding surface of the intermediate transfer belt 31 functions as a lubricant. , The wear and the generation of abnormal noise are suppressed.
Also in this case, by forming the supplementary toner image Ts in addition to the normal toner image Tg, the secondary transfer residue from the image area GE is left on the portion 31s of the intermediate transfer belt 31 where the plate-shaped cleaning member 37a comes into contact. In addition to the above toner, the colorless transparent toner (Ts2) remaining after the secondary transfer is supplied from the non-image area NE so as to be supplemented. As a result, the toner can be efficiently supplied to the contact portion 31s with less unevenness as compared with the case where only the normal toner image Tg is formed and the supplementary toner image Ts is not formed.

Then, as shown in FIG. 10B, a normal toner image Tg is fixed on one side of the continuous paper 9 output by this image forming operation after being secondarily transferred to form a formal image. Become.
At this time, the supplementary toner image (Ts) made of colorless transparent toner is also secondarily transferred to one side of the continuous paper 9 except for some toners (Ts2) that are not secondarily transferred, and finally by the fixing device 40. Be fixed. However, the supplementary toner image (Ts) after being fixed on the continuous paper 9 is colored because the supplementary toner image itself is formed so as to be difficult to see and is composed of colorless transparent toner. Compared with the case of the supplementary toner image Ts composed of toner, the result is more inconspicuous and more difficult to confirm with the naked eye.

<Modification 1 of Embodiment 2>
In the second embodiment, as illustrated in FIG. 2, a first gloss reading means (gloss meter) 72A for reading the surface gloss of the continuous paper 9 and an image are formed inside the housing 200 of the image forming unit 20. After providing the second gloss reading means (gloss meter) 72B for reading the surface gloss of the formed continuous paper 9, the surface gloss of the continuous paper 9 obtained from the gloss reading means 72A and 72B by the control means 61. The transparent image forming apparatus 21H may be configured to adjust the amount of colorless transparent toner used when forming the supplementary toner image Ts based on the reading information regarding the surface glossiness of the continuous paper 9 on which the image is formed. ..

In this case, the first gloss reading means 72A may be arranged at least at a position upstream of the secondary transfer position of the intermediate transfer device 30 in the transport direction C of the continuous paper 9, but in some cases, the supply unit 10 may be arranged. It may be arranged in the housing 11. Further, the second gloss reading means 72B may be arranged at least at a position on the downstream side of the conveying direction C in the conveying direction C from the fixing device 40, but in some cases, it is arranged in the housing 16 of the accommodating portion 15. It doesn't matter. The first gloss reading means 72A and the second gloss reading means 71B are connected to the control means 61 as shown in FIG.

Further, in this case, for the adjustment regarding the amount of the colorless transparent toner used when forming the supplementary toner image Ts by the control means 61, for example, as illustrated in FIG. 5, an adjustment determination unit 75 independent of the control means 61 is provided. After the adjustment determination unit 75 determines the amount of the colorless transparent toner used, it is possible to adopt a configuration in which the determined information is reflected in the control operation of the transparent image forming apparatus 21H by the control means 61. The adjustment determination unit 75 is connected to the control means 61 so that the detection information obtained by the gloss reading means 72A and 72B can be obtained.

In the adjustment determination unit 75, for example, the first gloss reading means 72A reads that the surface gloss of the continuous paper 9 is a value, and the second gloss reading means 72B determines the surface gloss of the continuous paper 9 on which the image is formed. Suppose a value significantly higher than the above value is read.
In this case, the adjustment determination unit 75 determines that it is preferable to make adjustments so as to reduce the amount of the colorless transparent toner used in the transparent image forming apparatus 21H when forming the supplementary toner image Ts made of the colorless transparent toner.
Further, when the adjustment determination unit 75 uses the continuous paper 9 having the surface glossiness to perform the image forming operation, the toner coverage rate per unit area of the supplementary toner image Ts and the surface glossiness of the image are determined. The measurement information is recorded, and for example, data showing the relationship between the toner coverage and the glossiness illustrated in FIG. 6B is created. By using this data, when forming a supplementary toner image Ts made of colorless transparent toner on the continuous paper 9 having the surface glossiness, it is determined to what value the toner coverage rate, which is difficult to see, is allowed. , The result can be reflected in the later control operation.

<Modification 2 of Embodiment 2>
Further, in the second embodiment, in addition to the transparent image forming device 21H, at least one of the four color image forming devices 21 (Y, M, C, K) is configured to form the supplementary toner image Ts. May be good.
In this case, the supplementary toner image Ts is also applied to the portion 22s of the photosensitive drum 22 of the image forming device 21 (Y, M, C, K) forming the supplementary toner image Ts where the cleaning member 27a of the drum cleaning device 27 comes into contact. The toner (Ts1) remaining on the transfer from the above can be supplied.

Further, in this case, in addition to the first gloss reading means 72A and the second gloss reading means 71B, the image forming unit 20 and the like are provided with the first color reading means 71A and the second gloss reading means 71A and the second gloss reading means 71A described in the first modification of the second embodiment. The color reading means 71B is provided, and the supplementary toner image Ts is provided by the image forming apparatus 21 (Y, M, C, K) based on the reading information regarding the color and image density of the continuous paper 9 obtained from the color reading means 71A, 71B. It may be configured to adjust one or both of the color of the toner and the amount of the toner used when forming the toner.

[Embodiment 3]
The image forming apparatus according to the third embodiment adopts a configuration in which the control means 61 controls the supplementary toner image Ts to be formed in a part of the non-image area NE, except that the image forming apparatus according to the first and second embodiments is formed. It has the same configuration as that of the device 1.

In this image forming apparatus 1, as illustrated in FIG. 11A, when the supplementary toner image Ts is formed by at least one of the image forming apparatus 21 (Y, M, C, K, H), each photosensitive member is exposed to light. Supplementary toner images Tsa, Tsb, Tsc, etc. are formed in the square non-image area NE sandwiched between the image forming surface of the drum 22 and the image area GE on which the normal toner image Tg is formed. doing. In the case of this illustrated configuration, the non-image area inside the image area GE, the non-image area that is the remaining portion of the image quality effective area YE outside the width direction E of the image area GE, and the image quality effective area YE. The supplementary toner image Ts is not formed in the non-image area that becomes the end portion Ee outside the width direction E.

When the supplementary toner image Ts is formed in a part of the non-image area NE in this way, in addition to similarly obtaining the effects described in the first and second embodiments, the supplementary toner image Ts is non-imaged. Compared with the case where it is not formed in a part of the region NE, the consumption amount of the toner used for forming the supplementary toner image Ts can be suppressed. When the image area GE occupies the entire area of the image quality effective area YE in the axial direction E (when there is a part of the image quality effective area YE without the image area GE in the rotation direction A), the supplementary toner image Ts is as follows. It will be formed in a part of the non-image area NE.

Further, in this image forming apparatus 1, as illustrated in FIG. 11B, when forming a supplementary toner image Ts with at least one of the image forming apparatus 21 (Y, M, C, K, H), In the non-image area NE sandwiched between the image forming surface of each photosensitive drum 22 and before and after the image area GE on which the normal toner image Tg is formed, and in the non-image area NE generated on the side of the width direction E of the image area GE. , The supplementary toner images Tsd, Tse, etc. are formed in a state of being distributed in the width direction E. The supplementary toner images Tsd and Tse illustrated in FIG. 11B are formed so as to exist alternately in a checkered pattern in, for example, the width direction E.

When the supplementary toner image Ts is formed in a state of being distributed in the width direction E of a part of the non-image area NE in this way, the effects described in the first and second embodiments can be obtained in the same manner. In addition, it is possible to suppress the amount of toner consumed and the uneven supply of toner in the axial direction E of the non-image area NE, as compared with the case where the supplementary toner image is not formed in the non-image area distributed in the width direction. can.

[Embodiment 4]
As shown in FIG. 12, the image forming apparatus 1B according to the fourth embodiment applies the direct transfer type paper transport device 80 instead of the intermediate transfer type intermediate transfer device 30, and uses the cut paper 90 as a recording medium. It has the same configuration as the image forming apparatus 1 (image forming unit 20) according to the first to third embodiments, except that it is changed to be used and the paper feeding device 45 is provided.

The paper transfer device 80 in the image forming apparatus 1B is required while passing through the transfer positions facing the primary transfer apparatus (transfer apparatus) 26 of the photosensitive drum 22 in the four image forming apparatus 21 (Y, M, C, K). A paper transport belt 81, which is an example of an image holder arranged so as to rotate in a direction, is provided. Further, in the paper transport device 80, a paper holding promotion device 85, a belt cleaning device 87, and the like are arranged around the paper transport belt 81.

The paper transport belt 81 is an endless belt member having a holding surface for holding the cut paper 90 by electrostatic action, and is rotatably supported by being hung around a plurality of support rolls 82 and 83.
The support roll 82 is configured as a drive roll, and the support roll 83 is configured as a surface-facing and tension-applying roll that holds the primary transfer surface of the paper transport belt 81 and applies tension in cooperation with the drive roll 82.
The paper transport belt 81 is rotationally driven in the direction indicated by the arrow J by receiving rotational power from a rotational drive device (not shown) from the drive roll 82. Further, from the inner peripheral surface side of the paper transport belt 81, the image forming apparatus 21 (Y, M, C, K) is formed by the primary transfer roll of the primary transfer apparatus 26 in the image forming apparatus 21 (Y, M, C, K). ) Is pressed against each photosensitive drum 22.

The paper holding promotion device 85 is a device that assists in holding the cut paper 90 by electrostatically adhering it to the holding surface which is the outer peripheral surface of the paper transport belt 81. In the paper holding promotion device 85, for example, the holding roll to which the adhesion voltage is supplied is brought into contact with the outer peripheral surface of the paper transport belt 81 in front of the image forming device 21Y at the most upstream position to hold the cut paper 90. It is configured.

The belt cleaning device 87 has substantially the same configuration as the belt cleaning device 37 in the intermediate transfer device 30, and has a plate-like cleaning inside the housing in which the tip corner portion is brought into contact with the outer peripheral surface of the paper transport belt 81. A member (elastic blade, etc.) 87a, a rotary cleaning brush 87b that rotates while contacting the outer peripheral surface of the paper transport belt 81, and a collection unit (not shown) that does not show unnecessary objects such as toner removed by the cleaning member 87a and the rotary cleaning brush 87b. A delivery member 87c or the like to be sent toward is arranged.

The paper feed device 45 is attached to the housing 200 so as to be retractable, and is accommodated in a state in which cut paper 90 of a desired size, type, etc. is stacked on a loading plate (not shown), and the accommodating body 46 thereof. It is configured to include at least a delivery device 47 that sends out the cut paper 90 one by one from the body 46 toward the paper feed transfer path 48. The number of the housing 46 and the sending device 47 may be increased or decreased as necessary. The paper feed transport path 48 is composed of a transport roll pair (not shown), a paper guide member, and the like.

<Basic image formation operation>
In this image forming apparatus 1B, the basic image forming operation described below is performed. Here, a case of forming a multicolor image composed by combining toner images of four colors (Y, M, C, K), a so-called full-color image, will be described as an example.

Similar to the case of the image forming apparatus 1 (image forming unit 20) according to the first embodiment, the image forming apparatus 1B receives four image forming apparatus when the central control means 60 receives a command requesting an image forming operation. At 21 (Y, M, C, K), the formation of the toner image is started in almost the same manner.

Next, the toner images of each color formed on the photosensitive drum 22 of each image forming apparatus 21 (Y, M, C, K) are transferred to the cut paper 90 conveyed by the paper conveying apparatus 80.

First, the cut paper 90 sent out from the accommodating body 46 of the paper feed device 45 by the delivery device 47 is conveyed through the paper feed transfer path 48, and the paper holding promotion device 85 is placed on the outer peripheral surface of the paper transfer belt 81 in the paper transfer device 80. It receives an auxiliary action and becomes electrostatically attached. Subsequently, the cut paper 90 rotates in the direction indicated by the arrow J of the paper transport belt 81, so that the transfer positions of the image-forming devices 21 (Y, M, C, K) facing the photosensitive drum 22 are sequentially moved. It is transported so that it passes through.
Subsequently, in each image forming apparatus 21 (Y, M, C, K), each transfer in which the toner images of each color formed on the photosensitive drums 22 face the paper transport belt 81 by the rotation of the photosensitive drums 22. It is transported to the position. The toner images of each color are transferred by being held by the paper transport belt 81 by the action of the transfer electric field formed between the primary transfer device 26 and each photosensitive drum 22 by receiving the transfer voltage. Each 90 is electrostatically sequentially transferred.
Further, the image forming surface of each photosensitive drum 22 after the transfer or the like is cleaned by each drum cleaning device 27 removing unnecessary substances such as toner. Further, the outer peripheral surface of the paper transport belt 81 after the transfer or the like is cleaned by the belt cleaning device 87 removing unnecessary substances such as paper dust and toner.

Next, the cut paper 90 on which the toner image is transferred is peeled off from the paper transport belt 81 and introduced into the fixing device 40.
In the fixing device 40, the cut paper 90 is introduced into the fixing processing section between the heating rotating body 42 and the pressing rotating body 43 and conveyed so as to pass therethrough, and is heated under pressure when passing therethrough. As a result, the toner image constituting the toner image is melted and fixed on the cut paper 90.
Finally, the cut paper 90 on which the image is formed by the completion of fixing is discharged and stored in a discharge accommodating portion (not shown) through the discharge port 202 of the housing 200.

By executing the above image forming operation, a full-color image formed by combining four-color toner images is formed on one side of the cut paper 90.

<Supplementary configuration related to the operation of forming a toner image>
Further, the image forming apparatus 1B is similar to the case of the image forming apparatus 1 according to the first embodiment of the drum cleaning apparatus 27 in the photosensitive drum 22 of each image forming apparatus 21 (Y, M, C, K). During the image forming operation, the toner is supplied to the portion 22s in contact with the cleaning member 27a and the portion 87s in contact with the cleaning member 87a of the belt cleaning device 87 in the paper transport belt 81 of the paper transport device 80. A control means 61 for executing an operation of forming a supplementary toner image Ts that is difficult to see is provided (see FIG. 5).

<Supplementary toner image formation operation and its action effect>
When the image forming operation is performed, the image forming apparatus 1B has each image forming device 21 (as illustrated in FIG. 14A) in substantially the same manner as in the case of the supplementary toner image forming operation in the first embodiment. In Y, M, C, K), in addition to forming a normal toner image Tg composed of any of the four colors on the photosensitive drum 22 in the image forming region D, it is illustrated in FIG. 14 (b). As described above, the supplementary toner image Ts composed of any of the four colors is formed in the non-image region NE on the image forming surface of the photosensitive drum 11.
At this time, the image forming region D becomes an region having a size and shape substantially equal to the size of the cut paper 90. Further, the non-image area NE at this time is a non-image area NE excluding the image area GE on which the normal toner image Tg of the image forming area D is formed, and an end Ee in the width direction E of the image quality guarantee area YE. It becomes a combined area.

Next, at the transfer position of each image forming apparatus 21 (Y, M, C, K), as shown in FIG. 15, the normal toner image Tg and the supplementary toner image Ts on the image forming surface of each photosensitive drum 22 Is sequentially transferred to the cut paper 90 which is held by the paper transport belt 81 and transported. Reference numeral W3 in FIG. 15 indicates the dimensions of the cut paper 90 in the width direction E.

At this time, as illustrated in FIG. 13, a part of the toner Ts1 constituting the supplementary toner image Ts is not transferred to the cut paper 90 and remains on the image forming surface of the photosensitive drum 22.
At this time, among the toners constituting the supplementary toner image Ts in each image forming apparatus 21 (Y, M, C, K), the toner Ts1 remaining without being transferred due to the above-mentioned principle of being charged in the opposite polarity is used in each photosensitive drum. It is conveyed by the rotation of the 22 and reaches the portion 22s on the image forming surface of the photosensitive drum 22 where the cleaning member 27a of each drum cleaning device 27 comes into contact with each other. At this time, among the toners constituting the normal toner image Tg, the toner that is not transferred due to the principle of being charged in the opposite polarity and remains on the image forming surface of the photosensitive drum 22 is also conveyed and reaches the above-mentioned portions 22s, respectively. do.

As a result, in each image forming device 21 (Y, M, C, K), the photosensitive drum 22 in the cleaning member 27a of each drum cleaning device 27 is similarly formed in the case where the supplementary toner image Ts in the first embodiment is formed. Since the toner (Ts1) that has reached the portion (tip corner portion) in contact with the image forming surface of the above functions as a lubricant, its wear and the generation of abnormal noise are suppressed.
Also in this case, by forming the supplementary toner image Ts in addition to the normal toner image Tg, the toner remaining transferred from the image area GE is applied to the portion 22s of the photosensitive drum 22 where the plate-shaped cleaning member 27a comes into contact. In addition, since the toner (Ts1) remaining to be transferred is supplied from the non-image area NE so as to be supplemented, the toner can be efficiently supplied to the contact portion 22s with less unevenness.

In the operation of forming the supplementary toner image Ts in the image forming apparatus 1B, FIG. 14 shows a portion that becomes a gap S1 between the image forming region D (cutting paper 90) and the image forming region D (cutting paper 90). The supplementary toner image Ts as shown in (b) and FIG. 15 is not formed.
However, when the supplementary toner image Ts is also formed in the portion (a type of non-image area) that becomes the gap S1, the supplementary toner image Ts is the outer peripheral surface of the paper transport belt 81 as illustrated in FIG. After the primary transfer to the paper transport belt 81, the cleaning member 87a of the belt cleaning device 87 can reach the contact portion 81s on the outer peripheral surface of the paper transport belt 81.
In this case, the portion of the cleaning member 87a of the belt cleaning device 87 that comes into contact with the outer peripheral surface of the paper transport belt 81 is a supplementary toner. Occurrence is suppressed.

<Modified Example of Embodiment 4>
In the image forming apparatus 1B according to the fourth embodiment, as in the case of the first modification of the first embodiment, as illustrated in FIGS. 12 and 5, the cut paper is formed inside the housing 200. After providing the first color reading means (color density sensor) 71A for reading the colors of 90 and the second reading means (color density sensor) 71B for reading the density of the image formed on the cut paper 90, the control means 61 Of the toner when the supplementary toner image Ts is formed by the image forming apparatus 21 (Y, M, C, K) based on the reading information regarding the color and the density of the image of the cut paper 90 obtained from the color reading means 71A and 71B. It may be configured to adjust one or both of the color and its usage.

Further, in the image forming apparatus 1B according to the fourth embodiment, as in the case of the second embodiment, a transparent image forming apparatus (21H) is added as an image forming apparatus, and the transparent image forming apparatus (21H) is colorless. It may be configured to form a supplementary toner image Ts from the transparent toner.
Further, in the case of the above-mentioned modification in the fourth embodiment in which the transparent image forming apparatus (21H) is added, the same as in the case of the first modification in the second embodiment, as illustrated in FIGS. 12 and 5. In addition, a first gloss reading means (gloss meter) 72A for reading the surface gloss of the cut paper 90 and a second gloss reading means (second gloss reading means) for reading the surface gloss of the cut paper 90 on which an image is formed are formed inside the housing 200. After providing the gloss meter) 72B, the control means 61 provides reading information regarding the surface gloss of the cut paper 90 obtained from the gloss reading means 72A and 72B and the surface gloss of the cut paper 90 on which the image is formed. Based on this, the transparent image forming apparatus 21H may be configured to adjust the amount of the colorless transparent toner used when forming the supplementary toner image Ts.

Further, the image forming apparatus 1B according to the fourth embodiment adopts a configuration in which the control means 61 controls the supplementary toner image Ts to be formed in a part of the non-image area NE, as in the case of the third embodiment. It doesn't matter.

[Other embodiments]
In the first to fourth embodiments, the control means 61 interrupts the formation of the supplementary toner image Ts according to the information of one or both of the normal toner image Tg forming amount and the continuous forming time thereof. It may be configured to be controlled.
For the amount of toner image Tg formed at this time, for example, a value obtained by accumulating and totaling the image pixel values of the toner image Tg can be adopted. Further, as the continuous formation time of the toner image Tg, a value obtained by measuring the elapsed time of the continuous image formation operation can be adopted.
Then, in this case, when the cumulative value of the image pixel value and the cumulative value of the continuous formation time exceed each of the preset threshold values, the supplementary toner image Ts while continuing the formation of the normal toner image Tg. It is only necessary to interrupt the formation of.

Further, with respect to the control means 61, the formation pattern of the supplementary toner image Ts or the amount of toner used is reduced according to the information of one or both of the normal toner image Tg forming amount and the continuous forming time thereof. It may be configured to control to change. The case of reducing the formation pattern of the supplementary toner image Ts is, for example, changing to a pattern in which the total area of the supplementary toner image Ts to be formed is reduced.
In this case as well, when the cumulative value of the image pixel values and the cumulative value of the continuous formation time exceed each of the preset threshold values, the supplementary toner image Ts while continuing the formation of the normal toner image Tg. The formation of the supplementary toner image Ts may be continued after the conditions are changed in the direction of reducing the formation pattern of the toner or the amount of the toner used.

Further, in the image forming apparatus 1 according to the first to third embodiments, the cut paper 90 may be used as the recording medium instead of the continuous paper 9.
Further, in the image forming apparatus 1B according to the fourth embodiment, the continuous paper 9 may be used as the recording medium instead of the cut paper 90. In this case, the continuous paper 9 can be configured to be temporarily held and transported by the paper transport belt 81 in the paper transport device 80.

Further, as the image forming apparatus, it is also possible to apply an image forming apparatus having a format other than the image forming apparatus 1 adopting the intermediate transfer method and the direct transfer type image forming apparatus 1B using the paper transport device 80. .. As another type of image forming apparatus, for example, one image forming apparatus 21 is provided, and a monochromatic toner image Tg and a supplementary toner image Ts are directly transferred from the photosensitive drum 22 to a recording medium (cut paper or continuous paper). A transfer type image forming apparatus can be mentioned.

1,1B ... Image forming apparatus 9 ... Continuous paper (example of recording medium)
21Y, 21M, 21C, 21K ... Image forming device (device including image forming means)
21H ... Transparent image forming device (device including image forming means)
22 ... Photosensitive drum (an example of an image holder)
22s ... Part where the plate-shaped cleaning member comes into contact 23 ... Charging device (Example of forming a part of the image forming means)
24 ... Exposure device (example forming a part of image forming means)
25Y, 25M, 25C, 25K ... Developing device (example of forming a part of image forming means)
25H ... Transparent developing device (example of forming a part of image forming means)
27 ... Drum cleaning device (an example of the first cleaning device)
27a ... Plate-shaped cleaning member 31 ... Intermediate transfer belt (example of image holder)
61s ... Part where the plate-shaped cleaning member comes into contact 37 ... Belt cleaning device (an example of the second cleaning device)
37a ... Plate-shaped cleaning member 61 ... Control means 71A, 71B ... Reading means 72A, 72B ... Glossy reading means 81 ... Paper transport belt (an example of an image holder)
81s ... Part where the plate-shaped cleaning member comes into contact 87 ... Belt cleaning device (an example of the third cleaning device)
87a ... Plate-shaped cleaning member 90 ... Cut paper (example of recording medium)
A, B, J ... Rotation direction E1, E2 ... Width direction NE ... Non-image area Tg ... Normal toner image Ts ... Supplementary toner image Ts1, Ts2 ... Supplementary toner image

Claims (9)

An image-forming means for forming a toner image according to image information,
An image holder that rotates to hold and transfer the toner image formed by the image forming means,
A cleaning device that brings a plate-shaped cleaning member into contact with the image holder,
When the toner image is formed by the image-forming means, a supplementary toner image that is difficult to see is formed in a non-image area where the toner image is not formed and held by the image holder, and the supplementary toner image is not transferred. A control means for executing an operation of bringing the toner remaining in the image holder to a portion in contact with the cleaning member, and
A reading means for reading the color of the recording medium on which the toner image is transferred and the density of the image consisting of the toner image transferred to the recording medium.
Equipped with a,
The control means either one of the toner colors and the amount used in the image forming means when forming the supplementary toner image based on the reading information regarding the color of the recording medium and the density of the image obtained from the reading means. An image forming device that adjusts both. The image forming apparatus according to claim 1, wherein the control means controls to form the supplementary toner image in a part of the non-image area. The image forming apparatus according to claim 2, wherein the control means controls to form the supplementary toner image in a state of being distributed in a width direction intersecting the rotation direction of the image holder in the non-image area. As the image forming means, a transparent image forming means for forming a transparent toner image made of colorless transparent toner is provided.
The image forming apparatus according to any one of claims 1 to 3, wherein the control means controls the transparent image forming means to form the supplementary toner image. A gloss reading means for reading the surface gloss of the recording medium on which the toner image is transferred and the surface gloss of the recording medium on which the image composed of the toner image is formed is provided.
The control means performs the transparent image formation when forming the supplementary toner image based on reading information regarding the surface glossiness of the recording medium obtained from the gloss reading means and the surface glossiness of the recording medium on which the image is formed. The image forming apparatus according to claim 4, wherein the amount of the colorless transparent toner used in the means is adjusted. The control means controls to interrupt the formation of the supplementary toner image or the formation pattern of the supplementary toner image or the amount of toner used according to the information of one or both of the formation amount of the toner image and the continuous formation time. The image forming apparatus according to any one of claims 1 to 5, which is controlled so as to change in a direction of reduction. The image holder includes a latent image holder and an intermediate transfer body, and as the cleaning device, a first cleaning device that brings a plate-shaped cleaning member into contact with the latent image holder and a plate-shaped cleaning member on the intermediate transfer body. Equipped with a second cleaning device to contact
The control means holds the supplementary toner image on the latent image holder and the intermediate transfer body, respectively, and removes the toner that is not transferred from the supplementary toner image and remains on the latent image holder in the first cleaning device. The operation of reaching the part where the cleaning member of the second cleaning member comes into contact and the operation of causing the toner remaining in the intermediate transfer body, which is not transferred from the supplementary toner image, to reach the part of the second cleaning device in contact with the cleaning member are executed. The image forming apparatus according to any one of claims 1 to 6. The image holder is provided with a latent image holder and a medium carrier for transporting the recording medium so that the recording medium is brought into contact with the latent image holder and passed through the latent image holder, and a plate-shaped cleaning member is provided on the latent image holder as the cleaning device. A first cleaning device for contact and a third cleaning device for contacting a plate-shaped cleaning member with the medium carrier are provided.
The control means holds the supplementary toner image on the latent image holder and the medium carrier, and cleans the toner image of the supplementary toner image that is not transferred and remains on the latent image holder for cleaning the first cleaning device. A claim for executing an operation of reaching a portion of contact with a member and an operation of causing the toner remaining in the medium carrier, which is not transferred from the supplementary toner image, to reach a portion of contact with the cleaning member of the third cleaning device. The image forming apparatus according to any one of 1 to 6. The image forming apparatus according to any one of claims 1 to 8 , wherein a continuous medium is used as a recording medium for transferring the toner image.

Images