JPH10171198A - Multicolor image forming device incorporating color erasable toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multicolor image forming device capable of easily performing the printing in coexistence of a color erasable toner printing part and the permanent color toner printing part. SOLUTION: The the main body device 10 is provided with detecting devices S1, S2, S3 and S4 for detecting where the color erasable toner developing device is normally mounted among mounting positions of four unites of developing devices 21a to 21d for magenta, cyan, yellow and black. The controlling part firstly inquires whether the color erasable toner developing device is mounted or not (M1), and when not mounted ('absent' in M1), the printing process is performed in 'no color erasing normal printing mode' (step M2). While, if the color erasable toner developing device is mounted ('present-in M1), the printing is executed, in 'color erasable + monocolor printing mode' for the printing with use of the color erasable toner and an arbitrary color toner (M3), in 'color erasable + full color printing mode' for the printing with use of the color erasable toner and the full color (M4), or in 'color erasable only printing mode' for the printing with use of the color erasable toner only (M5).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multicolor image forming apparatus for forming an image in which a decolorable toner image and a permanent color toner image are mixed.

[0002]

2. Description of the Related Art As shown in FIG. 4, there is a conventional decolorizing toner for resource saving and a copying machine using the decolorizing toner. The copying machine 1 shown in FIG. 1 includes two developing units A and B that are alternately detachable from the image forming unit 2. One developing unit, for example, developing unit A contains decolorized toner, and the other developing unit B usually contains black toner. These developing units A or B are selectively selected as necessary, and the mounting to the copying machine 1 can be switched.

In FIG. 1, a plurality of sheets P placed in a sheet cassette 3 are conveyed by a sheet feed roller 4 one by one along a conveying path 5 to the downstream (to the left in the figure). The photosensitive drum 2-1 of the image forming unit 2 is provided with a uniform charge on the peripheral surface thereof by the initialization charger 2-2, and the exposure head 2-3
As a result, an electrostatic latent image is formed on the peripheral surface of a uniform charge, and the electrostatic latent image is converted into a decolorized toner image by the developing roller 2-4 of the developing unit A. The decolorized toner image is transferred by the transfer unit 2-5 onto the paper surface of the sheet P conveyed along the conveyance path 5, and is thermally fixed by the fixing unit 6. The sheet P on which the decolorized toner image has been fixed is discharged as an image-formed sheet P1 outside the apparatus.

The image-formed paper P1 is passed through a decoloring machine 7 having a light source 7-1 for near-infrared light (light near 820 nm), such as a halogen lamp, for example. (Generally blue) can be colorless. In other words, this makes it possible to erase the image formed on the sheet P1. The sheet P2 that has been blanked after the image is erased is placed on the sheet cassette 3 again as the sheet P and reused. This contributes to resource recycling.

[0005] It is assumed that it is troublesome to replace the two developing units A and B with each other, and to attach and detach the two developing units, the two developing units A and B are mounted inside, and the developing operation is performed by one of the switching devices. A method of selectively switching to a developing unit has also been proposed.

[0006]

Since the above-described method for forming a decolorable toner image is based on printing by a copying machine, there has been no idea of editing a document in various ways. That is, there is no other image forming method except for selectively using one of the black toner and the decoloring toner. Therefore, a document formed on the paper is entirely composed of a single color using either black toner printing or decoloring toner printing, and basically, a black printing part and a decoloring printing part are mixed on one sheet of paper. There is no idea. Of course, a method of passing the black-printed paper once again to the copying machine to perform the decoloring printing is conceivable, but it is not practical. Also, it is not known that it has been put to practical use.

On the other hand, there is an increasing demand for full-color printing apparatuses (printers). However, in this case, too, the degree of coloring is the most important issue, so that a total of four developing units of three primary color toners and black toner are used. Other than the above, there was no idea to use the decolorizable toner as described above.

[0008] The object of the present invention is to solve the above-mentioned conventional situation,
An object of the present invention is to provide a multicolor image forming apparatus capable of easily performing printing in which a decolorized toner printing section and a permanent color toner printing section are mixed.

[0009]

The construction of a multicolor image forming apparatus according to the present invention will be described below. First, according to the first aspect of the present invention, a step of forming a predetermined color toner image on an image carrier is performed for each color, and the plurality of color toner images are arranged inside a transfer material transporting member that circulates and moves. The transfer means is applied to a multicolor image forming apparatus which sequentially superimposes and transfers a multicolor image on a transfer material carried and conveyed on the outer surface of the transfer material conveying member.

The multicolor image forming apparatus of the present invention includes a developing device for accommodating a decolorizable toner, and forms a toner image with the decolorizable toner in one of the toner image forming steps to form a toner image on a transfer material. After the image mixed with the toner image of another color is transferred to the image forming apparatus, a fixing process is performed.

Next, in a second aspect of the present invention, a step of forming a predetermined color toner image on the image carrier is carried out for each color, and the plurality of color toner images are transferred to the transfer material conveying member circulating. It is assumed that a multicolor image forming apparatus forms a multicolor image by successively superimposing and transferring a transfer material carried and conveyed on the outer surface of the transfer material conveying member by a transfer means disposed inside.

A multicolor image forming apparatus according to the present invention includes a developing device containing a decoloring toner which decolorizes in response to irradiation from a specific light source, and a mounting position recognizing means for recognizing a mounting position of the developing device. An order storing means for storing an order in which the toner image forming step is performed by the decolorable toner based on the recognition by the mounting position recognizing means; and an eraser for selecting image information for executing image formation by the decolorable toner. The image processing apparatus includes a color image information selection unit, and a control unit that forms an image based on the image information selected by the erased image information selection unit and the order information stored in the order storage unit.

[0013] For example, as described in claim 3, four developing units which accommodate color toners and are arranged in a multi-stage manner,
Each of the four developing units is provided with four developing means arranged corresponding to the arrangement positions of the four developing units so as to perform the toner image forming step.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a tandem-type color image forming apparatus (multicolor image forming apparatus) according to an embodiment.
FIG. A multicolor image forming apparatus (main body apparatus) 10 shown in FIG.
And a paper cassette 12 is detachably provided at a lower portion. A large number of sheets (transfer materials) are placed and stored in the sheet cassette 12. An upper lid 13 is provided on the upper surface of the main body device 10. A power switch, a liquid crystal display device, a plurality of input keys, and the like are arranged on the front side of the upper lid 13 although not shown in the drawing. The upper part of the upper cover 13 is
The paper discharge tray 14 is formed together with the upper surface of the rear part of the paper tray.

A transfer / conveying belt 15 (transfer material conveying member) is disposed substantially in the center of the main unit 10 in a flat loop shape in the front-rear direction. It is held by a driven roller 17. The transfer conveyance belt 15 is driven by a driving rotation roller 16 and circulates in a counterclockwise direction in the drawing.

In the upper circulating portion of the transfer / conveying belt 15,
The four photosensitive drums 18 (18a, 18b, 18c, 1
8d) are arranged side by side in a multi-stage manner in the paper transport direction (from right to left in the figure). A cleaner, an initialization charging brush, and a writing head 19 (19a, 19b, 19c, 1c) surround these photosensitive drums 18 (image carriers), respectively.
9d), developing units 21 (21a, 21b, 21c, 21)
d) and the transfer brush 22 (22a, 22b, 22c, 2
2d) is arranged. Transfer brush 22 (transfer means)
Is disposed inside the transfer / transport belt 15 and presses against the photosensitive drum 18 via the transfer / transport belt 15 to form a transfer section.

Each developing unit 21 has a developing roller rotatably supported by a lower opening thereof in contact with the peripheral surface of the photosensitive drum 18 to form four developing units. Developing device 21
The developing device 21a on the upstream side (right side in the drawing) in the sheet transport direction
, A magenta toner M, a cyan toner C, a yellow toner Y, and a decoloring toner E are sequentially stored from the developing device 21d to the downstream developing device 21d.

The writing head 19 is disposed on the back surface of the upper lid 13, descends as the upper lid 13 is closed, and is positioned between the initialization charging brush and the developing roller of the developing device 21. A recording unit is formed on the recording medium. In the loop of the transfer belt 15, a rotating arm 23 is disposed between the upper circulation portion and the lower circulation portion of the transfer conveyance belt 15 and extends in parallel with the conveyance direction. The rotating arm 23 has a fixed support roller 24 at one end and a movable support roller 25 at the other end.

The fixed support roller 24 is rotatably fixed to and supported by the frame of the main unit 10. The fixed support roller 24 is provided near the upstream side of the transfer brush 22 d closest to the drive roller 16. The fixed support roller 24 is disposed in contact with the inner peripheral surface of the transfer / transport belt 15 so that the photosensitive drum 18 at the most downstream position and the transfer / transport belt 15 are always in contact.

The free end side (right side in the figure) of the turning arm 23 turns up and down around the fixed support roller 24. The above-mentioned movable support roller 25 located at its free end
Abuts on the inner peripheral surface of the transfer conveyance belt 15 at a position between the transfer brush 22a closest to the driven roller 17 and the driven rotation roller 17, and supports the transfer conveyance belt 15.

When the rotating arm 23 rotates downward from the position shown in the figure, the movable support roller 25 moves downward and separates from the transport belt 15, and the upper circulation portion of the transfer transport belt 15 is fixed to the drive roller 16, Support roller 24 and driven roller 1
Supported between seven. In other words, it is separated from the three remaining photosensitive drums 22a to 22c that are in contact with the photosensitive drum 22d.
Thus, a print mode using only the decoloring toner E stored in the developing device 21d is set. In addition, the transfer brush 2
2 d is fixed to the frame of the main body device 10, and the other three transfer brushes 22 a to 22 c are fixed to the rotating arm 23 and move downward together with the rotating arm 23 to move from the transfer conveyance belt 15. Separate.

A cam engaging portion 26 is formed at a lower portion of the rotating arm 23 so as to project at right angles to the side. A cam 27 slidably abuts the cam engaging portion 26. .
The cam 27 is rotated 90 degrees in both the forward and reverse directions about the fulcrum 28 to selectively position the rotating arm 23 at the position shown in the figure or at any one of the upper and lower positions lowering downward. This figure shows a state in which the cam 27 is rotated 90 degrees in the counterclockwise direction and the whole is set to the full color print mode. In the full-color printing mode, as will be described later in detail, full-color printing without decoloring toner, full-color printing with decoloring toner, and mixed printing of decolorizing toner and an arbitrary color toner can be performed.

A tension roller 29 is disposed so as to press against the back surface of the lower circulating portion of the transfer belt 15. The tension roller 29 presses the transfer conveyance belt 15 downward by a rotating member 29 urged downward by an urging member 31. Thereby, the bending of the transfer conveyance belt 15 is absorbed, and the entire transfer conveyance belt 15 is stretched between the driving roller 16 and the driven roller 17 with a predetermined tension.

At the upstream (right side) end of the transfer / conveying belt 15, a suction roller 33 is in pressure contact with the driven roller 17 via the transfer / conveying belt 15, thereby forming a paper carrying section. . The suction roller 33 applies a suction bias to the paper conveyed into the paper conveyance unit and presses the transfer conveyance belt 15 to apply the suction bias to electrostatically adsorb the paper on the transfer conveyance belt 15.

On the upstream side (the right side in the drawing) of the transfer conveyance belt 15 in the conveyance direction, a standby roll pair 34 and a paper detection sensor 35
The upstream side is branched laterally (in front of the apparatus) and downward, and the paper feed roller 36, the separating member 37, and the opening / closing tray 11 described above are disposed laterally. A transport path 38 formed by two guide plates is provided below, and the above-described paper cassette 12 is located upstream (below). A paper feed roller 39 is disposed above a paper feed end of the paper cassette 12.

Further, a separation claw 41, a fixing device 42, a sheet discharge roller 43, and a switching lever 44 are provided downstream of the transfer conveyance belt 15 in the sheet conveyance direction (left side in the drawing). Fixing device 4
2 is a pressure contact roller, a fixing roller, a heating roller, a peripheral surface cleaner, an oil application member,
It is composed of a thermistor or the like, and heat-fixes the toner image transferred on the paper to the paper surface. The switching lever 44 guides the sheet to an upper discharge path 45 when it is at a lower position as shown in FIG. Guide to Discharge path 4 above
The downstream side (upper side) of 5 is connected to an upper discharge port 48 via a discharge roll pair 47.

A cleaner bottle 51 is detachably provided between the transfer / conveyer belt 15 and the paper cassette 12. A blade scraper 52 is attached to the upper portion of the cleaner bottle 51, and the tip of the blade scraper 52 is in contact with the surface of the lower circulation portion of the transfer / transport belt 15. The blade scraper 52 scrapes toner remaining on the surface of the transfer conveyance belt 15 to clean the transfer conveyance belt 15, and stores the scraped unnecessary toner in the cleaner bottle 51.

Further, between the belt 15 and the paper cassette 12, an electrical unit 53 to which a predetermined number of circuit boards can be mounted is provided behind the cleaner bottle 51. A control device (mounting position recognizing means, order storage means, erased image information selecting means, control means) comprising a plurality of electronic components is mounted on a circuit board provided in the electric component 53. Electrical part 5
A fan 54 is disposed at the rear of the unit 3 and discharges heat radiated from the electrical unit 53 and heat leaked from the fixing unit 42 to the outside of the apparatus.

Although not shown, the control device comprises a controller and an engine. The controller section
It comprises a CPU (Central Processing Unit), a ROM (Read Only Memory), an EEPROM (Rewritable Read Memory), a frame memory, an image data transfer circuit, etc., and analyzes print data input from a host computer or the like. Create print data and transfer it to the engine.

The engine unit includes a CPU, a ROM, and the like.
On the input side, data and command signals from the controller unit, outputs of a developing device position detection sensor described later, a paper detection sensor 3
5, a motor driver for driving a motor (not shown) on the output side, a clutch driver for switching a drive system for transmitting the drive of the motor to each unit, and a write head 1.
9 that drives the printer 9 based on the printing data, an initialization charging brush, a developing roller, a transfer brush 22,
A bias power supply driver or the like that supplies a predetermined bias current to the suction roller 33 and the like is connected. The engine unit drives and controls each unit based on data and command signals from the controller unit, outputs of various sensors, and the like.

Next, the operation of the multicolor image forming apparatus 10 having the above configuration will be described with reference to FIG. 1 again. First, the processing operation in the print mode using only the decoloring toner E will be described. In FIG. 1, when power is supplied to the apparatus main body 10 and paper quality, the number of sheets to be used, a print mode, and other designations are input as a key input or a signal from a connected host device, a driving mechanism (not shown) The cam 27 is driven to rotate the rotation arm 23 downward, whereby the movable support roller 25 moves downward and separates from the transfer conveyance belt 15. Thereby, the transfer conveyance belt 15 maintains the state of contact between the driving roller 16 and the fixed support roller 24 on the one hand with the photosensitive drum 18d, and the other remains between the fixed support roller 24 and the driven roller 17 on the other hand. It is separated from contact with the photosensitive drums 18a, 18b and 18c. As a result, only the transfer portion of the decoloring toner E formed by the most downstream photosensitive drum 18d and the transfer brush 22d is formed so as to be operable, and the print mode using only the decoloring toner E is set.

Subsequently, the paper feed roller 39 is moved to the paper cassette 12
Is fed to the standby roll pair 34 via the conveyance path 38. Alternatively, the paper feed roller 36 feeds the paper placed on the open / close tray 11 to the standby roll pair 34. The fed paper P is detected by a paper detection sensor 35.
Is detected. The standby roll pair 34 stops rotating, and the paper P
The sheet feeding is temporarily stopped by bringing the leading end of the sheet into contact with the holding portion, and the conveyance timing is awaited.

The driving roller 16 rotates counterclockwise, and the driven roller 17 is driven to rotate similarly in the counterclockwise direction. As a result, the transfer transport belt 15 circulates counterclockwise as a whole, with the upper circulating portion abutting on the most downstream photosensitive drum 18d.

At the same time, the developing unit 21d and the photosensitive drum 18d are driven in accordance with the printing timing. The photosensitive drum 18d rotates clockwise, the initialization charging brush applies a uniform high negative charge to the peripheral surface of the photosensitive drum 18d, and the writing head 19d causes the photosensitive drum 18d to rotate.
Exposure is performed on the d peripheral surface according to the image signal to form a low potential portion. As a result, an electrostatic latent image composed of a high negative potential portion due to the initialization and a low negative potential portion due to exposure is formed. The developing roller of the developing device 21d transfers the decolorable toner to the low potential portion of the electrostatic latent image and
A decoloring toner image is formed (reverse development) on the peripheral surface d.

When the leading end of the decolored toner image on the peripheral surface of the photosensitive drum 18d is rotated and conveyed to a point facing the transfer / conveying belt 15, the printing start position of the paper P coincides with the point. Thus, the standby roll pair 34 starts rotating and feeds the sheet P to the sheet carry-in section.

The driven roller 17 and the suction roller 33 convey the fed paper P while nipping the fed paper P together with the transfer / transport belt 15. The sheet P is attracted to the transfer / conveyance belt 15 and is conveyed to the most downstream transfer section formed by the photosensitive drum 18d and the transfer brush 22d.

The transfer brush 22d applies a transfer current output from a transfer bias power supply (not shown) to the sheet P via the transfer and conveyance belt 15. The erased toner image on the photosensitive drum 18d is transferred to the sheet P by the applied transfer current, and an erased toner image is formed on the sheet P.

The paper P on which the decolorized toner image has been transferred in this manner is separated from the transfer / conveyance belt 15 by the separation claw 41 and is carried into the fixing device 42. The fixing device 42 heat-fixes the toner image to the paper P. After fixing the erased image,
The paper P is discharged outside the machine by the discharge rollers 43 with the decolorized toner image facing upward from the rear discharge port 46 or with the decolorizable toner image facing downward from the upper discharge port 48.

Next, in the decolorizing toner and full color, decolorizing toner and arbitrary color toner, or full color printing mode without decoloring toner, the rotating arm 23 is rotated upward. As a result, the movable support roller 25 moves upward, and the transfer / conveyance belt 15 is moved to all four
(18a, 18b, 18c, 18d).

In the multi-color printing mode, the processing operation in the printing mode using only the decoloring toner E described above is different from the above-described processing operation in the printing mode using only the decolorizing toner E in the case where the decolorizing toner and the full color are mixed. When printing is controlled, in the case of printing in which the decoloring toner and the arbitrary color toner are mixed, the control of the exposure operation for the writing head 19 corresponding to the unused color toner is stopped. In the case of full-color printing without the decoloring toner, the control of the exposure operation on the writing head 19d corresponding to the decolorizing toner image forming unit is suspended. Subsequent processing operations are substantially the same as those in the print mode using only the decoloring toner.

The developing device 21d containing the decolorizable toner
The (developing unit) is detachable from the main unit 10 like the other developing units 21a to 21c. Also, the shape is the same as the other developing units 21a to 21c except for the detection unit. Therefore, the mounting position is not limited to the most downstream image forming unit. When not in use, it may be detached from main unit 10. The removal from the main unit 10 when not in use in this manner may be performed similarly for the other developing units 21a to 21c.

FIG. 2 is a diagram schematically showing the operation of control of the electrical component unit 53 by the above-described control device. As shown in FIG. 1, the main body device 10 includes detection devices S1, S2, S3, and S4 for detecting the mounting positions of the developing devices 21a, 21b, 21c, and 21d corresponding to the colors of the stored toner.
Are arranged.

In the above-mentioned tandem type color image forming apparatus, usually, the developing units 21a, 21b, 21c and 21
“d” contains magenta, cyan, yellow, and black toners. In the present embodiment, any one of the four developing devices used in the mounting position is replaced with a decolorizing toner developing device (in FIG. 1, the developing device 21d is replaced with a decolorizing toner developing device). This makes it possible to realize printing in which erasable images and ordinary non-erasable images are mixed in a single paper transport process. The image forming mode for printing is automatically selected according to the mounting position of the decolorizing toner developing device.

The detection devices S1, S2, S3 and S described above
Reference numeral 4 is formed corresponding to the detected device formed in the developing devices 21a to 21d. For example, when individual developing characteristics are provided for the developing devices 21a to 21d, a detection device that mechanically detects the mounting of a specific developing device in one-to-one correspondence with the individual characteristics of the shape is provided. . For example, if a concave portion is provided at a different position on the bottom for each developing device, and four movable projections corresponding to the concave portion are respectively disposed in the developing device mounting portion on the main unit side, the concave portion of the mounted developing device can be accommodated. The other protruding pieces are pushed in while leaving only one protruding piece, so that the controller unit of the electrical unit 53 determines whether or not the developing device is mounted, and the type of the mounted developing device (color of toner). When,
The respective mounting positions can be recognized.

When the developing device is formed so that the color of the toner contained therein can be recognized from the outside, a detecting device for optically detecting the toner color and individually recognizing the developing device is provided. . For example, a transparent window is provided in the developing device, and a reflection-type optical sensor is provided at a position corresponding to the window on the main device side. Since the toner has different light reflection characteristics depending on colors, whether or not the developing device is mounted, the type of the mounted developing device (toner color), and the mounting position are determined according to the reflectance and the wavelength of the reflected light. Can be recognized.

The conductors are provided in different shapes or at different positions for each developing device, and two electrodes corresponding to the shapes or positions of the respective conductors are provided on the main unit side. When the developing device is mounted, only two electrodes corresponding to the shape or position of the conductor of the mounted developing device are energized. This makes it possible to recognize whether or not the developing device is mounted, the type of the mounted developing device (color of toner), and the mounting position.

Alternatively, on the display device of the operation panel, the graphic images of the four developing units and “OFF”, “black”, “red”, “blue”,
The color name of the “yellow” toner and the like are displayed, and the combination of the position of the developing device and the color name of the toner is selected and determined by key input by the operator, whereby the number of the mounted developing devices and the mounting thereof are determined. The type (toner color) of the developed device and the mounting position thereof may be recognized. In any case, the type and the mounting position of the recognized developing device are stored in the memory.

As described above, the developing device 21 is usually
a, 21b, magenta at the mounting position of 21c and 21d,
Cyan, yellow, and black developing units are mounted (the position is determined for each color). This arrangement is stored in the control unit of the electrical unit 53. Here, a specific shape is provided only in the decoloring toner developing device, for example, a convex portion is provided in a part, and a light transmission type optical sensor is provided at a position of the main body device corresponding to the convex portion,
The decoloring toner developing device is used for the magenta, cyan, yellow,
Alternatively, when mounted in exchange for one of the black developing units, the above-mentioned convex portion may block the optical path of the optical sensor of the main unit to detect the mounting of the decoloring toner developing unit and its position. Good. Of course, the detection device according to the other method described above may be provided only for the decoloring toner developing device. FIG. 2 described above shows a flow of processing performed by such a configuration.

As shown in the figure, when printing is performed based on image data transmitted from the host device, first, referring to the contents stored in the memory, whether the decoloring toner developing device is mounted or not. It is checked whether or not it is (step M1). If it is not mounted ("none" in step M1), the printing process is performed in the "non-decoloring normal print mode" which does not include the decoloring toner (step M2). this is,
It performs normal full-color printing and black printing. As described above, when the decoloring toner developing device is not installed at any position, the “normal printing mode without decoloring” is automatically selected.

On the other hand, if the decolorizable toner developing device is mounted ("Yes" in step M1), printing including the decolorable toner is performed (step M3, M4 or M5). In this case, whether the decoloring toner and any color toner are to be printed (step M
3) Whether to print with decolorized toner and full color (step M4) or to print only with decolorized toner (step M5), image data or a command signal input from the host device or an operator. The setting is made in advance by any key input from the operation panel. In the case of using image data, for example, characters specified by a specific hatching pattern or double underline are printed with the decoloring toner. Alternatively, it is also possible to designate the toner color of the developing unit removed in exchange for the erasing toner developing unit and perform the erasing toner printing on the designated portion.

In the "decolorization + monocolor print mode" for printing the decolorable toner and an arbitrary color toner, any one of the magenta, cyan, and yellow developing units is replaced with the decolorizing toner developing unit. When attached (detection state by the detection device S1, S2 or S3 in FIG. 2), full color reproduction is impossible, but it is mainly used for black printing, and the decolored printing part is included in it. It is effective. In this case, in addition to black and decoloring, it is also possible to perform monocolor (monochromatic) printing using the toner color of the attached developing device.

The "decolorization + full-color printing mode" for performing printing with decolorized toner and full color is performed when the decolorized toner developing device is mounted in place of the black toner developing device (detected by the detecting device S4 in FIG. 2). State). In this print mode, all colors including decoloring can be formed by reproducing black print by superimposing three colors of magenta, cyan, and yellow.

In the "erasing only printing mode" in which printing is performed using only the decoloring toner, only the decolorizing toner developing unit is mounted and all the other developing units are removed. Developing device 2 with black toner developing device
By mounting the decolorizing toner developing device at the position 1d and rotating the rotating arm 23 downward, the operation can be performed in the same manner as in the normal monochrome printing mode using one color of black toner.
Each of these print modes is selected when the user attaches the developing device to the main device.

FIG. 3 shows an example of printing in the case of performing mixed printing of the above-described decolorizable toner and full-color toner, or a mixture of the decolorizable toner and an arbitrary color toner. FIG.
Is an example of paper P-1 in which is printed with an arbitrary color toner, the headings 56 and the like are printed in full color as appropriate so as to be conspicuous, and the numeral 57 in the ruled line frame 55 is printed with the decolorizing toner. For example, after printing business results and examining the results based on the business results at the board of directors or executive committee, etc., when applying to the decoloring machine 58, only the numeral 57 disappears and the ruled line frame 55 is blank.
It becomes 2. This will keep confidentiality, and if you print the next business results on this, you can use the paper repeatedly for meetings, contributing to resource saving by recycling this paper, and from the next printing In addition, the amount of toner used to print the ruled line frame 55, the heading 56, and the like can be saved, which is a great advantage.

For example, although not particularly shown, in POP printing, frames and characters are generally printed in red and blue in many cases, and the contents of the description are a product name, a simple advertising phrase, and a unit price. Further, in POP printing for notifying a bargain sale, the unit price is often changed depending on the day. In such a case, if the unit price is printed with the decolorizable toner (generally blue) and the frame and the advertisement are made of the red and blue of the permanent color toner, it will contribute to saving both the permanent color toner and the paper. Can be.

In a full-color printing image, a normal color image is first formed by using an erasable toner at a portion where blue (cyan) is used as a permanent color toner, and the image output by an erasing machine is obtained. It can be applied to play such as "changing picture", such as changing to an image with a strange color or changing to an image with a different pattern, and it can not be obtained by printing with the decoloring toner alone by a copier There is.

As described above, in addition to the above-described example, the printing use in which the decoloring toner is mixed with the normal toner is used.
For example, the general contents of the normal printing and the confidential contents of the decoloring printing are simultaneously printed in advance, and after the circulation of the related persons is completed, the confidential matters are deleted and the general circulation is performed. In addition, information such as an arrangement form and internal precautions that are not related to video information, which are items to be input such as an OCR description and an image, are erased and printed.
When R is used, it is erased and used. In addition, it is possible to erase and print necessary data when creating an image sample or a presentation material, and to erase the color when using it for exhibition and presentation.

In the above-described embodiment, any one of the tandem-type image forming apparatuses provided with four developing units is replaced with a decolorizing toner developing unit. Without limitation, a tandem image forming apparatus may be used, and an image forming apparatus in which five developing units of magenta, cyan, yellow, black, and decoloring toner are arranged in parallel. In this case, the function of “full color + decoloring” is always obtained. Also, instead of the tandem type, "1
An image forming apparatus of a color printing system such as “drum + multiple developing machine” or “intermediate transfer system” may be used to perform the above-described printing of the decoloring toner and the printing of the permanent color toner.

[0059]

As described above, according to the present invention,
Since the image printing is performed by mixing the decolorizing toner and the full-color permanent color toner, it is possible to easily print an image in which the part to be erased and the part to be left as they are later are intricately combined. Printing and erasing can be repeatedly used for the contents that are repeatedly updated, so that the paper can be recycled, thus contributing to resource saving. In addition, the format, general-purpose contents, permanent contents, and the like can be left without being erased, and therefore, it can be conveniently reused repeatedly as functional paper.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a tandem color image forming apparatus (multicolor image forming apparatus) according to an embodiment.

FIG. 2 is a diagram schematically illustrating an operation of control by a control device of an electrical unit.

FIG. 3 is a diagram illustrating a printing example in a case where mixed printing of a decoloring toner and a permanent color toner is performed.

FIG. 4 is a diagram illustrating a conventional copier using a decolorizable toner for the purpose of saving resources.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Copier 2 Image forming part 3 Paper cassette 4 Paper feed roller 2-1 Photoconductor drum 2-2 Initializing charger 2-3 Exposure head 2-4 Developing roller 2-5 Transfer device 5 Transport path 7 Decoloring machine 7 -1 Near-infrared light source A, B Developing unit P Paper P1 Image-formed paper P2 Paper reduced to white paper 10 Image forming apparatus (main unit) 11 Openable tray 12 Paper cassette 13 Top lid 14 Paper discharge tray 15 Transport transfer belt 16 Drive Roller 17 Follower roller 18 (18a, 18b, 18c, 18d) Photoconductor drum 19 (19a, 19b, 19c, 19d) Write head 21 (21a, 21b, 21c, 21d) Developing device 22 (22a, 22b, 22c, 18d) 22d) transfer brush 23 rotating arm 24 fixed support roller 25 movable support roller 26 cam engaging portion 27 cam 28 fulcrum 29 tension roller 31 urging member 32 rotating member 33 suction roller 34 standby roll pair 35 paper detection sensor 36 paper feed roller 37 separating member 38 transport path 39 paper feed roller 41 separation claw 42 fixing device 43 paper discharge roller 44 switching lever 45 Discharge path 46 Rear discharge port 47 Discharge roll pair 48 Upper discharge port 51 Cleaner bottle 52 Blade scraper 53 Electrical unit 54 Fan 55 Ruled line frame 56 Heading 57 Number 58 Decoloring machine P-1 Decoloring toner and permanent color toner Paper S-2, S3, S4 Detecting device where only the printed portion of the decoloring toner is erased

Claims (3)

[Claims] 1. A step of forming a toner image of a predetermined color on an image carrier is performed for each color, and the toner images of the plurality of colors are transferred by a transfer unit disposed inside a transfer material conveying member that moves in a circulating manner. A multicolor image forming apparatus for sequentially forming a multicolor image by sequentially superimposing and transferring a transfer material carried and conveyed on the outer surface of the transfer material conveying member, comprising: a developing device for accommodating a decolorized toner; Forming a toner image with the decolorizable toner in one of the steps, transferring an image mixed with another color toner image onto a transfer material, and then performing a fixing step. Image forming device. 2. A process for forming a predetermined color toner image on an image carrier is performed for each color, and the plurality of color toner images are transferred by a transfer unit disposed inside a circulating transfer material conveying member. In a multicolor image forming apparatus for sequentially forming a multicolor image by successively superimposing and transferring a transfer material carried and conveyed on the outer surface of the transfer material conveying member, a decoloring toner which decolors in response to irradiation from a specific light source is provided. The stored developing device, a mounting position recognizing means for recognizing a mounting position of the developing device, and an order storing means for storing an order in which the toner image forming step using the decolorizable toner is performed based on the recognition by the mounting position recognizing means. An erased image information selecting means for selecting image information for executing image formation using the erased toner; an image information selected by the erased image information selecting means and an order stored in the order storage means. Based on information There are multi-color image forming apparatus characterized by comprising control means for forming an image, a. 3. Four developing units which contain color toners and are arranged in a multi-stage manner, and each of the four developing units is arranged at a position where the four developing units are arranged so as to perform the toner image forming step. 3. The multicolor image forming apparatus according to claim 2, further comprising: four developing units arranged correspondingly.