JPH0659591A - Image forming device provided with decoloring function - Google Patents

Abstract

PURPOSE:To provide a new image forming device provided with a decoloring function capable of performing an image forming process such as copying and decoloring processing for transfer paper by the same device. CONSTITUTION:In this device, an electrostatic latent image is formed on a photoconductive photosensitive body 10 and developed with decoloring toner, and the obtained decoloring toner image is transferred and fixed on the transfer paper, so that the image is formed. The device is provided with a decoloring means by an infrared light lamp 33 arranged on a transfer paper carrying path 20 leading to a transfer paper ejection part 16 from a decoloring toner image transfer part 12 and a control means 40 controlling the decoloring means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having an erasing function.

[0002]

2. Description of the Related Art Decoloring toner, that is, toner that is made transparent by light irradiation or heating is being put to practical use. For example, a functional infrared absorbing dye having the structural formula shown in FIG. 8: IR820B and an “ammonium salt of organoboron” such as tetrabutylammoniumbutyltriphenylborate are co-dispersed in a transparent resin have been proposed. (Functional Pigment Subcommittee Material No. 17; Kinki Chemical Association Functional Pigment Subcommittee, distributed on May 29, 1991). Decolored toner that is decolorized by heating is also known.

The above color erasable toner, which has a blue color before being erased, has an absorption maximum at a wavelength of 825 nm and has a near-infrared light in a wavelength region near this wavelength or It is made transparent by irradiating light (for example, light of a halogen lamp) containing such an infrared light component. When the decoloring toner is used, the "decoloring toner image" formed on the transfer sheet is erased and made transparent, so that the transfer sheet can be repeatedly used, which is an effective measure for saving paper resources.

A dedicated erasing apparatus is intended as an apparatus for erasing an image with an erasing toner, but it is space-consuming to provide an erasing apparatus in addition to an image forming apparatus (for example, a copying machine). If there is a problem and if you want to make a copy immediately with the decolorized transfer paper if the copy machine and the decolorization processing device are installed in different places, install the decolorized transfer paper on the copying machine. It is troublesome to carry it to a place.

Therefore, it is desirable that the image forming apparatus itself for forming an image with the decoloring toner has a decoloring processing function. As a method for providing the image forming apparatus itself with an erasing function, for example, since the above-mentioned photo-decolorable toner is made transparent by irradiation of light from a halogen lamp, a document illumination scanning unit in the image forming apparatus is used. However, in order to perform erasing with a halogen lamp, it is necessary to set the lamp emission energy per unit time to be considerably higher than during original document scanning. There is also a problem that the temperature of the original glass rises to an undesired temperature due to the action of heat.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an image forming process such as copying and a decoloring process of a transfer sheet can be performed by the same apparatus, and An object of the present invention is to provide a novel image forming apparatus having a decoloring processing function without the problem of the temperature rise of the original glass.

[0007]

SUMMARY OF THE INVENTION The image forming apparatus of the present invention provides a method of forming an electrostatic line image on a photoconductive photoconductor, developing the electrostatic line image with a decoloring toner, and obtaining the decolorized toner image obtained. An apparatus for forming an image by transferring and fixing on a transfer paper ", and has an erasing means and a control means (claim 1).

The "color erasing means" is composed of one or more infrared light lamps provided on the transfer paper conveying path from the color erasing toner image transfer portion to the transfer paper discharge portion. The “control unit” is a unit that controls the decoloring unit, and specifically, a computer that controls the image forming apparatus can be used.

The image forming apparatus of the present invention may of course have a developing device for developing with normal toner together with a device for developing with decoloring toner, or the above-mentioned 2
The developing device of the kind may be exchangeable.

The color erasing means can be constituted by "a plurality of small infrared light lamps are arranged in close contact with each other in the width direction of the transfer paper and each infrared light lamp can be independently blinked" ( Claim 2). In this specification, the "transfer paper width direction" means a direction orthogonal to the carrying direction on the paper surface of the transfer paper carried through the erasing means, regardless of the vertical and horizontal directions of the actual transfer paper. .

An image forming apparatus according to a second aspect of the present invention also has "a means for detecting the width of the transfer sheet, and a small infrared lamp is lit according to the detected width of the transfer sheet to carry out the decoloring process". (Claim 3). To detect the width of the transfer paper, a detection method utilizing the structure of the transfer paper setting portion in the cassette has been known, and in the invention of claim 3, as the means for detecting the transfer paper width, These publicly known ones can be appropriately used.

The image forming apparatus according to the second aspect of the present invention further includes "a decoloring area designating unit for designating a desired portion in the formed image as a decoloring area, and a small red color corresponding to the designated decoloring area. It is possible to control the blinking of the external light lamp. " Various methods are conventionally known for designating a desired area of a formed image in association with a digital copying apparatus or the like. For example, a method of reading the original or reading the information of the floppy disk and displaying it on the display, specifying the area by moving the cursor and key operation on the display, or a desired area on the original with a special color It is possible to use a method of marking the area with the ink marker and surrounding the marked area with a document reading device and designating the inside or outside of the marked area as a designated area, or a method of designating the area on the original glass with a touch pen or the like.

Further, a method of controlling blinking of a small infrared light lamp so as to erase a designated erased area is a conventional eraser control in a method of erasing an unnecessary area of an electrostatic latent image by an eraser. It can be executed with similar control.

As a small infrared lamp, it is desirable that the length in the arrangement direction is about 5 mm to 20 mm.

In the image forming apparatus according to claim 1, 2 or 3 or 4, the infrared light lamps are arranged at "the entrance side and / or the exit side of the pressure contact portion between the fixing roller and the pressure roller". It can be defined (Claim 5).

In the image forming apparatus according to the first aspect of the present invention, "Infrared light lamps are arranged at the inlet side and / or the outlet side of the pressure contact portion between the fixing roller and the pressure roller, and the decoloring means is energized. And energization to the heat source of the fixing roller can be selected, and energization of one side stops energization of the other "(claim 6). That is, claim 1
In the image forming apparatus described in the above, there is a case where "it is not necessary to perform the decoloring process when the fixing is performed, and it is not necessary to perform the fixing when the decoloring process is performed". This is because it is not necessary to operate the erasing means at the same time.

In the image forming apparatus according to the fifth or sixth aspect of the present invention, "infrared lamps are provided on both sides of the transfer sheet transport path (front and back sides of the transported transfer sheet), and Image detecting means for detecting the presence or absence of the decolored toner image is provided, and the infrared lamp on the side for decoloring the detected decolorized toner image is turned on ”(claim 7).

[0018]

As described above, in the present invention, the decoloring means is provided "on the transfer paper conveyance path from the decolorized toner image transfer section of the image forming apparatus to the transfer paper discharge section", and therefore, the conventional image forming apparatus can be used. The erasing function can be realized with almost the same layout, and the original glass is not heated by the erasing means. Further, since the decoloring means is composed of an infrared lamp, it is possible to use an infrared lamp as the decoloring light to perform the decoloring processing of the light decoloring toner by using the infrared light as the decoloring light. Then
The heat treatment of infrared light can also perform the decoloring treatment of the thermally decolorizable toner.

[0019]

EXAMPLES Specific examples will be described below. FIG. 1 schematically shows only the characteristic part of the image forming apparatus according to the first aspect. In this embodiment, the invention according to claim 1 is applied to an ordinary electronic copying machine. That is, in the normal copying mode, the document is placed on the document glass and illuminated and scanned, and the light image of the document is projected and irradiated onto the circumferential surface of the uniformly charged drum-shaped photoconductor 10 to form an electrostatic latent image. It is formed. This electrostatic latent image is developed with normal toner or decoloring toner, the obtained toner image is transferred onto the transfer paper by the transfer charger 12, the transfer paper is separated from the photoconductor 10 by the separation charger 14, and the fixing device 16 is provided. Thus, the toner image is fixed and discharged onto the tray 18.

In FIG. 1, reference numeral 20 indicates a transfer paper transport path. The starting point of the transfer sheet conveying path 20 is the sheet feeding section, and the ending point is the tray 18. The "paper feed unit" is a "paper feed cassette" and a "manual paper feed unit" installed in the copying apparatus main body.

A lower guide plate 31 and an upper guide plate 32 are provided in the vicinity of the front side of the fixing device 20 in the transfer paper conveying path 20, and the transfer paper conveyed is fixed to the fixing roller 16A.
It is designed to guide the pressure contact portion (nip portion) between the pressure roller and the pressure roller. The upper guide plate 32 constitutes a housing structure together with a cover member 34, and an infrared light lamp 33 is incorporated therein, and a portion separating the infrared light lamp 33 and the transfer paper conveyance path 20 is heat resistant so as not to absorb infrared light. Dustproof glass 35
Has become. Infrared lamp 33 and dustproof glass 35
Have a length equal to or larger than the maximum transfer paper width in the direction orthogonal to the drawing. The cover member 34 is of course formed of a material that blocks infrared light. It is desirable that the inner surface of the cover member 34 be a reflecting surface that reflects infrared light in order to enhance the decoloring efficiency.

The control section 40 is a control means and controls the infrared light lamp 33, that is, the erasing means. The control unit 40 is specifically a computer and also controls the entire copying apparatus.
This copying apparatus can switch between the normal copying mode and the erasing mode described above, and when the erasing mode is selected, the control unit 40 performs erasing among the functions of each unit required for the copying operation. Only the portion required to convey the transfer sheet to be processed by the transfer sheet conveying path 20 is operated, and other operations are stopped. Therefore, the heat source built in the fixing roller 16A in the fixing device 16 does not generate heat. This is because the decoloring process does not require heating of the decolorized toner image by the fixing device.

The infrared lamp 33 is turned on by the operation of the control unit 40. When the transfer paper to be erased is conveyed from the paper feeding section, the transfer paper is conveyed in the direction of the arrow through the transfer paper conveying path 20, and when passing between the upper and lower guide plates 32 and 31, an infrared lamp is used. Infrared light is emitted by 33 to erase the decolored toner image, and the toner image is further conveyed by the conveying action of the fixing device 16 and discharged onto the tray 18. In order to reliably perform the erasing, in the erasing mode, the transfer paper conveyance speed is set to be slower than the transfer paper conveyance speed in the normal copying mode by the control unit 40.

The infrared lamp 33 is turned off in the above-mentioned normal copying mode. Therefore, in the embodiment described above, the energization of the heat source in the fixing roller 16A and the energization of the infrared light lamp 33 are selective, and when one is energized, the other is not energized. Therefore, the above embodiment is also an embodiment of the invention described in claim 6.

FIG. 2 shows an embodiment of the invention according to claim 3 in FIG.
Only the parts used in the embodiment modified from the above embodiment are schematically shown. In this embodiment, the erasing means 30 (which is arranged on the front side of the fixing device (not shown) as in the case of the embodiment of FIG. 1) is provided with small infrared light lamps 30a, 30b ,. ． ，
30i ,. ． Has a structure that is closely arranged in the width direction of the transfer paper, and each infrared lamp can blink independently.

When the width of the transfer sheet conveyed on the transfer sheet conveying path is detected by the transfer sheet width detecting section 50, the result is taken into the control section 40. For example, assuming that the width of the transferred transfer paper is A, B and C as shown in the figure, the control unit 40 controls the width: A within the range: a in the erasing means 30 when the width A is detected. Only the infrared light lamps of the above are turned on, when the width: B is detected, only the infrared light lamps within the range: b are turned on, and when the width: C is detected, all the infrared light lamps are turned on. However, effective erasing processing is performed according to the transfer paper width,
Reduces energy consumption due to unnecessary lighting of infrared lamps.

FIG. 3 shows an embodiment of the invention according to claim 4 in FIG.
Only the parts used in the embodiment modified from the above embodiment are schematically shown. The erasing means 30 is the same as that described with reference to FIG. However, in this embodiment, the erasing means 30 is provided on the tray side of the fixing device. Then, the erasing means 30 is operated in a normal copying process for developing with the erasing toner.

That is, prior to the copying process, the erasing area on the original is designated by the erasing area designating means 60 using a known appropriate area designating means. The result is the control unit 40.
Is taken into. When the copying process is performed, an electrostatic latent image corresponding to the entire original image is formed and developed with decoloring toner. The obtained decolorized toner image (corresponding to the entire original image) is transferred onto the transfer paper and fixed on the transfer paper by the fixing device.

The transfer paper having the decolorized toner image fixed thereon subsequently passes through the position of the decoloring means 30, and at this time, the control section 40.
Controls the blinking of the infrared lamps 30a, 30b, etc. in accordance with the fetched data of the erased area, and selectively erases the erased toner image in the area designated as the erased area. Dispose on the tray. In some cases, the transfer paper from which the erased toner image in the erased area has been erased is returned to the transfer unit again, and another toner image (either an erased toner image or a normal toner image may be transferred to the erased area. The so-called image composition may be carried out by transferring and fixing the image formed on the photoconductor during the erasing process).

FIG. 4A schematically shows an example in which the image forming apparatus according to claim 7 is applied to the apparatus of the embodiment shown in FIG. The upper guide plate 32 side provided on the front side of the fixing device is configured as a color erasing unit similar to the embodiment of FIG. 1, and the lower guide plate 310 side is configured as a color erasing unit similar to the upper guide plate side. Has been done.

A pair of decoloring toner image detecting means 71, 72 are provided on the transfer paper transport path for the transfer paper S so as to sandwich the transfer paper transport path. Decoloring toner image detecting means 71,
Reference numeral 72 denotes an optical coupler including a light emitting element that irradiates the transfer paper S with light and a light receiving element that floats the reflected light from the transfer paper.
When the decolorized toner image is formed, separately from the original image,
A mark M for detection as shown in FIG. 4B is formed by the decoloring toner at a predetermined position on the transfer paper S. The mark M is transferred to the above-mentioned predetermined position on the transfer paper S when the decolorized toner image is transferred.

The decoloring toner image detecting means 71, 72 detect the presence or absence of the decoloring toner image on the front and back sides of the transfer sheet S conveyed through the transfer sheet conveying path in the decoloring mode, and send the result to the control section 40. . The control unit 40, depending on the detection result,
The decoloring means on the front surface side and / or the back surface side of the transfer paper is operated to erase the decolored toner image on the front surface and / or the back surface. By doing so, when there are decoloring toner images on the front and back of the transfer sheet S, they can be decolorized at the same time, the efficiency of decoloring processing is good, and when there is a decoloring toner image on only one side. Can be transported to the transfer paper transport path without causing the upper and lower sides of these to have a good workability in the erasing process.

A modified example will be described below. First, in each of the above embodiments, the erasing means is provided only on one side of the fixing device, but the erasing means may be provided on both sides of the fixing device. In this case, in the case of the color erasing means 30 as shown in FIGS. 2 and 3, the array pitch of the infrared light lamps in each color erasing means is shifted by a half pitch so that the array of small infrared light lamps is a so-called "staggered pattern". "
Can be By doing so, the minimum width of erasing can be reduced to 1/2 of the arrangement pitch of the small infrared light lamps.
Can be

In the embodiment of FIG. 1, in the decoloring means which also serves as a guide plate to the fixing device, the portion separating the infrared light lamp and the transfer paper conveying path is dustproof glass, but this portion is shown in FIG. The configuration may be "lattice-like" as in the embodiment shown in FIG.
In this case, if the directions of the grids are parallel to each other and face the transfer paper transport direction, the irradiation of infrared light from the infrared lamp will cause "unevenness", so transfer the grid directions as shown in the figure. By inclining with respect to the paper transport direction, infrared light is uniformly irradiated on the entire surface of the transfer paper.

The modification of FIG. 6 can be applied to any of the embodiments of FIGS. 1, 2, 3, 4, and 5. As shown in the figure, the cylinder lens 42, which is long in the direction orthogonal to the drawing, effectively collects the infrared light of the infrared lamp 33 on the transfer paper S, and the decoloring process can be performed efficiently. .

By the way, in the invention according to claim 6,
When the color erasing process of the color erasing toner image on the transfer paper is performed, the fixing is not performed, and at this time, the heat source inside the fixing roller is not energized. However, since the color-erased toner image to be color-erased is in a "softened state" due to the thermal action of infrared light, the pressure contact force between the fixing roller and the pressure roller in the fixing device is as large as during normal fixing. And when the decolorized transfer paper passes through the fixing section, “wrinkles” appear on the transfer paper.
Is likely to occur. For this reason, in the case of the invention of claim 6, it is desirable to reduce the pressure contact force between the fixing roller and the pressure roller when the decoloring process is performed.

FIG. 7 shows an example of a mechanism for switching the pressure contact force between the fixing roller and the pressure roller between high and low. The fixing roller 16A is fixedly supported by a stationary member (not shown),
The pressure roller 16B is provided so as to be movable in the vertical direction in the drawing, and is pressed against the fixing roller 16A with a predetermined fixing pressure in the longitudinal direction by a pressure mechanism.

The pressurizing mechanism has a shaft 1050 attached to a stationary member of the apparatus.
The pressure lever 1051 is swingably supported by the pressure lever 1051, and a spring 1052 that is stretched between the free end of the pressure lever 1051 and the immovable member and applies a clockwise torque to the pressure lever 1051. The above-mentioned torque presses the pressure roller 16B upward to realize the necessary fixing pressure.

The fixing pressure switching means includes the above-mentioned pressurizing mechanism,
It is composed of an eccentric cam 1053 and a drive mechanism 1054. The eccentric cam 1053 engages with the upper side of the pressure lever 1051 near the free end of the pressure lever 1051 and is rotationally driven by the drive mechanism 1054. The illustrated state is a state during fixing, and the fixing pressure is set to the high pressure side.

When the fixing pressure is switched to the low pressure side by the command from the control unit 40, the drive mechanism 1054 receiving the control signal from the control unit 40 rotates the eccentric cam 1053, and the pressure lever 1051 is rotated counterclockwise. Rotate. Along with this, the pressing force for pressing the pressure roller 222 upward is reduced, and the fixing pressure is switched to the low pressure side.

[0041]

As described above, according to the present invention, it is possible to provide a novel image forming apparatus having a decoloring function. Since the present invention is configured as described above, the image forming process such as copying and the decoloring process of the transfer paper can be performed by the same apparatus, and there is no problem of the temperature rise of the original glass. According to the third aspect of the invention, it is possible to suppress wasteful energy consumption according to the width of the transfer sheet and perform effective erasing processing,
According to the fourth aspect of the invention, it is possible to edit the image by utilizing the erasing process. Furthermore, the invention according to claim 6 is excellent in energy saving, and the invention according to claim 7 is good in efficiency and workability of decoloring treatment.

[Brief description of drawings]

FIG. 1 is a diagram for explaining one embodiment of the present invention.

FIG. 2 is a diagram for explaining another embodiment.

FIG. 3 is a diagram for explaining another embodiment.

FIG. 4 is a diagram for explaining still another embodiment.

FIG. 5 is a diagram for explaining a modified example.

FIG. 6 is a diagram for explaining another modified example.

FIG. 7 is a diagram for explaining an essential part of another modified example.

FIG. 8 is a structural formula of a dye used in a photo-erasable toner.

[Explanation of symbols]

 10 Photoconductive Photoreceptor 12 Transfer Charger 20 Transfer Paper Conveying Path 33 Infrared Light Lamp 16 Fixing Device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI Technical indication location G03G 15/22 103 Z 6830-2H 21/00 (72) Inventor Keizo Yasuda Nakamagome, Ota-ku, Tokyo 1-3-6, Ricoh Co., Ltd. (72) Inventor Masahiko Sato 1-3-6 Nakamagome, Ota-ku, Tokyo, Ricoh Co., Ltd. (72) Eiji Sawamura 1-chome Nakamagome, Ota-ku, Tokyo No. 3-6 in Ricoh Co., Ltd. (72) Inventor Yasuhisa Kato 1-3-6 Nakamagome, Ota-ku, Tokyo In Ricoh Co., Ltd.

Claims (7)

[Claims] 1. An electrostatic line image is formed on a photoconductive photoconductor, the electrostatic line image is developed with a decoloring toner, and the decolorized toner image obtained is transferred and fixed on a transfer paper to form an image. An apparatus, comprising: an erasing means by an infrared lamp provided on a transfer paper conveying path from a erasing toner image transfer section to a transfer paper discharging section, and a control means for controlling the erasing means. An image forming apparatus having a erasing function, which is characteristic. 2. The image forming apparatus according to claim 1, wherein the erasing means comprises a plurality of small infrared light lamps closely arranged in the transfer paper width direction, and each infrared light lamp is independent. An image forming apparatus, which is capable of blinking. 3. The image forming apparatus according to claim 2, further comprising means for detecting the width of the transfer paper, and a small infrared light lamp is lit in accordance with the detected width of the transfer paper to perform the decoloring process. An image forming apparatus characterized by the above. 4. The image forming apparatus according to claim 2, further comprising an erasing area designating unit for designating a desired portion in the formed image as an erasing area, and a small red color corresponding to the designated erasing area. An image forming apparatus characterized by controlling blinking of an external light lamp. 5. The image forming apparatus according to claim 1, 2 or 3 or 4, wherein the infrared light lamp forming the erasing means is an inlet side and / or an outlet side of a pressure contact portion between the fixing roller and the pressure roller. An image forming apparatus, which is characterized in that the image forming apparatus is installed in. 6. The image forming apparatus according to claim 1, wherein an infrared lamp is provided at an inlet side and / or an outlet side of a pressure contact portion between the fixing roller and the pressure roller, and the decoloring means is energized. An image forming apparatus, wherein energization to a heat source of a fixing roller is selectable, and energization of one side is stopped when energizing one side. 7. The image forming apparatus according to claim 5, wherein infrared light lamps are provided on both sides of the transfer paper conveyance path, and image detection is performed to detect the presence or absence of decolorized toner images on the front and back of the transfer paper. An image forming apparatus comprising means for illuminating an infrared light lamp on the side for erasing the detected decolorized toner image.