JP3098622B2 - Image forming apparatus for reversible thermosensitive recording film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to image formation of a reversible thermosensitive recording film which can be used for image recording of a plain paper sheet and a reversible thermosensitive recording film by an electrophotographic process such as a copying machine, a facsimile or a printer. Related to the device.

[0002]

2. Description of the Related Art In recent years, protection of the global environment including forest resources has become one of the major issues in various industrial fields. In the OA equipment industry, the reuse of recording sheets used in image forming apparatuses such as copying machines has been steadily executed as part of this environmental protection measure. Currently, a method of recycling recording sheets generally collects used recording sheets, collects the collected recording sheets, and performs a chemical treatment in a reprocessing plant such as a paper mill to produce recycled paper.
However, in such a chemical treatment method, there is a physical limit (the progress of fiber decomposition) in the number of reprocessings, and a certain amount of new wood is required when performing the reprocessing.

On the other hand, as another method of reusing a recording sheet, a recording material which is rewritable and can be used repeatedly as many times as possible, specifically, a reusable recording material which is initialized by heating to a predetermined temperature. Various examination proposals have been made for a method using a simple recording material (hereinafter referred to as a reversible thermosensitive recording film; referred to as a TC film) because of its easy handling.

[0004]

SUMMARY OF THE INVENTION The present invention examines a reusable TC film among the above-mentioned prior arts. By the way, all of the conventional methods of forming an image on a TC film are configured to record image information by directly contacting a heating means (thermal head) on the film surface. Although various uses of the TC film are considered, a copier, a laser facsimile, and the like, which are widely spread and use a large amount of paper and are expected to have a great effect of reusing the paper, are expected. Alternatively, in an image forming apparatus such as a laser beam printer, an apparatus capable of applying the TC film has not yet been put to practical use. This is because, in a conventional image forming apparatus, an electrophotographic process is generally used as an image forming method. Therefore, in order to be able to apply a TC film to this type of image forming apparatus, a conventional electrophotographic process means is used. In addition to the above, an image forming unit (for example, a heating unit, a conveying unit, a control unit, etc.) dedicated to the TC film must be newly provided. That is, an image forming apparatus having such a configuration in which an image forming means dedicated to a TC film is added is, in other words, an apparatus which is merely a combination of a conventional copying machine or the like with an image forming apparatus for a TC film. Although no technical difficulty is recognized, it is inevitable that the cost of the device, the size of the device, and the complexity of the image forming control system will inevitably increase from the viewpoint of the entire device. it is conceivable that.

[0005] In view of the above, the image forming means dedicated to the TC film and the image forming means dedicated to the plain paper sheet are configured so as to share the same means, thereby providing a large-scale image forming means dedicated to the TC film. Without adding an image, an image can be formed on a TC film by using an electrophotographic process for forming an image on an existing plain paper sheet. However, the existing electrophotographic process for forming an image on a plain paper sheet does not have an erasing means for erasing the recorded image of the TC film by heat generation, so that the TC film on which the image is recorded can be used. In order to achieve this, it is necessary to provide an erasing means dedicated to the TC film. For this reason, in an apparatus that simply shares an electrophotographic process for forming an image on an existing plain paper sheet, T
It is necessary to newly provide erasing means dedicated to C film,
The size and cost of the device cannot be expected to be very high.

The present invention has been made in view of the above points, and has as its object to create an image on an existing plain paper sheet without adding a large-scale image forming means dedicated to a reversible thermosensitive recording film. Enables image formation on a reversible thermosensitive recording film using an electrophotographic process for image formation, and initializes a recorded reversible thermosensitive recording film using an existing heat source (erasing a recorded image) It is an object of the present invention to provide a reversible thermosensitive recording film image forming apparatus capable of suppressing the increase in cost and apparatus volume and the complexity of an image forming control system.

[0007]

SUMMARY OF THE INVENTION The present invention comprises an image forming means for forming an image on a plain paper sheet for image recording, and a reusable reversible thermosensitive recording which is initialized by heating to a predetermined temperature. An image forming apparatus having an image forming unit for forming an image on a film and a heat fixing device for heating and fixing an image on a plain paper sheet, wherein the heat fixing device is switched between a heated state and a non-heated state. Having a switching means, when the reversible thermosensitive recording film passes through the heating / fixing device for initialization, to a heated state, and when the film passes for image formation, to a non-heated state; Is switched.

[0008]

According to the present invention, when the reversible thermosensitive recording film passes through the heating / fixing device of the image forming apparatus for initialization, it is in a heated state, and when it passes for image formation, it is in a non-heated state. When the heat fixing device is switched by the switching unit, initialization or image formation on the reversible thermosensitive recording film is performed.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

However, the configuration and operation of the range that can be clearly recalled from the description of this specification are omitted or simplified in order to avoid complication of the description.

An image forming apparatus according to an embodiment of the present invention includes a plain paper sheet (hereinafter, simply referred to as plain paper), a reversible thermosensitive recording film, and a thermochromic film (hereinafter, TC).
(Hereinafter abbreviated as film), an image can be recorded using a common image forming means. As shown in FIG. 1, the image forming apparatus of this embodiment includes a sheet feeding tray A,
It has two paper feed trays, a paper feed tray B. These paper feed trays A and B are respectively arranged in parallel, and both paper feed trays are configured without any difference. Here, for convenience of explanation, it is assumed that a TC film is set in the sheet feeding tray A and plain paper is set in the sheet feeding tray B.

First, image recording on plain paper in the embodiment will be described. In FIG. 1, a bundle of plain paper set in the paper feed tray B is pulled out of the paper feed tray B by the paper feed roller 1, and the uppermost one is separated by the separation pad 35.
Only the sheet is conveyed by the rotation of the paper feed roller 1. The plain paper transported by the paper feed roller 1 is transported by the transport roller 37 to the registration driving roller 9 and the registration driven roller 40.
Is transported to a pair of registration rollers, and is abutted against the nip portion of the registration roller. At this time, the leading edge of the plain paper is detected by the pre-registration sensor 31, and
The timing of image writing on the plain paper is set.

On the other hand, while the plain paper is fed and conveyed as described above, an original image is written as a latent image on the photoreceptor 10 by the optical unit 5, and the latent image on the photoreceptor 10 is The image is visualized by the toner supplied from the developing unit 4. Next, the plain paper sent out toward the photoreceptor 10 by the registration roller rotating at a timing by the pre-registration sensor 31 is transferred to the transfer separation unit 8.
As a result, the toner image is transferred from the photoconductor 10. The plain paper to which the toner image has been transferred is conveyed toward the fixing unit 34 while being attracted to the conveyance guide plate 13 by the suction force of a fan 36 provided on the back surface side of the conveyance guide plate 13. The plain paper conveyed to the fixing unit 34 is pressed and heated by the pair of pressure roller 19 and heating roller 20 to fix the transferred toner image.

Downstream of the fixing means 34, a TC cleaning means 24, which functions only when recording an image on a TC film, is provided.
This TC cleaning means 24 is indicated by an arrow a in FIG.
It is retracted to the position displaced in the direction (the position shown by the solid line). Thus, the plain paper discharged from the fixing unit 34 guided by the fixing outlet upper guide plate 22 and the fixing outlet lower guide plate 23 is left
The paper is further conveyed by a paper ejection tray 8 and is discharged onto a paper discharge tray 30 by paper discharge rollers 29 through a paper discharge guide plate 28.

Next, image recording on a TC film in the embodiment will be described. In FIG.
The bundled TC film set in is fed out of the paper feed tray A by the paper feed roller 1, and only the uppermost one is conveyed by the rotation of the paper feed roller 1 by the separation pad 35. Here, in the embodiment, the TC film set on the sheet feeding tray A is initialized (whitened) in advance. The TC film transported by the paper feed roller 1 is transported by a transport roller 37 to a pair of resist rollers including a resist driving roller 9 and a resist driven roller 40, and is abutted on a nip portion of the resist roller. At this time, the leading end of the TC film is detected by the pre-registration sensor 31, and the timing of writing an image on the TC film is determined.

On the other hand, while the TC film is fed and conveyed as described above, the optical unit 5
The original image is written as a latent image by the
The latent image on 0 is visualized by the toner supplied from the developing unit 4. Next, the toner image is transferred from the photoconductor 10 by the transfer separation unit 8 to the TC film sent out toward the photoconductor 10 by the registration roller rotating at a timing by the pre-registration sensor 31. The image forming process on the TC film so far is not different from the image forming process on the plain paper described above.

At the time of image recording on the TC film, the TC film to which the toner image has been transferred is attracted to the transport guide plate 13 by the suction force of the fan 36 disposed on the back side of the transport guide plate 13. When the sheet is conveyed while being conveyed, the irradiation lamp 16 of the irradiation means 15 disposed opposite the conveyance guide plate 13 with the conveyance path interposed therebetween.
Lights up. The irradiation light of the irradiation lamp 16 is reflected by the reflection plate 1.
7 and the condenser lens 18, the T
Light is focused and irradiated on the film surface of the C film. At this time, the TC film itself is in a cloudy state, and an unfixed toner image is transferred to the surface of the TC film. Therefore, the irradiation light irradiated and condensed by the irradiation lamp 16, the reflection plate 17, and the condensing lens 18 is absorbed by the unfixed toner image portion which is a black portion on the film surface of the TC film, and the black portion is Even if the temperature is increased, the other portion of the film surface which becomes cloudy (non-image portion) is reflected and has no effect. As a result, a temperature difference occurs between the toner image portion and the non-image portion on the film surface of the TC film, and only the toner image portion of the TC film changes color from a cloudy state to a transparent state due to the temperature difference. On the TC film surface, an image composed of a cloudy portion (non-image portion) and a transparent portion (toner image portion) is recorded.

The TC film on which an image has been recorded due to the heat discoloration of the opaque portion is conveyed toward the fixing means 34 while being attracted to the conveyance guide plate 13 by the suction force of the fan 36. Here, at the time of recording an image on the TC film, the film surface of the TC film conveyed to the fixing means 34 comes into contact with the heating roller 20 and is reheated, so that the image recorded on the film surface is In order not to lose the heat, the heating roller 20 of the fixing means 34 is displaced in advance in the direction of arrow b in FIG.
It is retracted to a position where it does not contact the film surface of the TC film (dashed line position), that is, a position where the heat of the heating roller 20 is not transmitted to the TC film.

At the time of recording an image on the TC film, the TC cleaning means 24 moves the arrow a in FIG.
Back to the position displaced in the opposite direction (the position indicated by the dashed line), and the back surface of the TC film (the surface on which the toner image is not transferred) of the transport rollers 38 composed of a pair of rollers
The blade 25 of the cleaning means 24 is in contact with the peripheral surface of the roller 38a located at the position. Here, the contact force of the blade 25 against the roller 38a is determined by the frictional force between the roller 38a and the TC film.
It is set to be larger than the frictional force with the C film. Thus, the TC film that has passed through the fixing unit 34 without being reheated is guided by the fixing outlet upper guide plate 22 and the fixing outlet lower guide plate 23, and
It is transported according to the rotation of a. When the TC film is transported by the roller 38a, the toner transferred onto the film surface is scraped off by the blade 25. The toner scraped off from the surface of the TC film is collected in a collection bottle 27 by a collection roller 26 provided in the cleaning unit 24.
The TC film on which the image composed of the cloudy part (non-image part) and the transparent part (image part) is recorded by scraping off the transfer toner in this manner is further transported by the transport roller 38 composed of a pair of rollers. The sheet is guided by a sheet ejection guide plate 28 and is ejected by a sheet ejection tray 3 by sheet ejection rollers 29.
Drained above zero.

In FIG. 1, the paper feed guide plate 2 is
It has a function of guiding while the plain paper and the TC film fed by the paper feed roller 1 are conveyed to the registration drive roller 9 and the registration driven roller 40. The pre-transfer guide plate 11 has a function of guiding the plain paper or the TC film conveyed by the registration driving roller 9 and the registration driven roller 40 toward the photoconductor 10. Fixing entrance upper guide plate 14 and fixing entrance lower guide plate 3
Reference numeral 9 denotes plain paper separated from the photoreceptor 10 and T or
It has a function of guiding the C film to the nip between the pressure roller 19 and the heating roller 20 of the fixing unit 34. The thermistor T provided in the fixing unit 34 is
0 has a function of detecting the surface temperature of the heater 2, and the heater 2 disposed in the heating roller 20 based on the detection signal.
The heating temperature of the heating roller 20 is varied by controlling the amount of heat generated in the heating roller 20. The charging unit 6 provided around the photoconductor 10 has a function of initializing the surface potential of the photoconductor 10 by discharging. A paper discharge sensor 32 arranged on the conveyance path of the paper discharge guide plate 28 detects whether or not the plain paper or the TC film conveyed from the fixing unit 34 passes at a predetermined timing, and jams the plain paper or the TC film. And so on.

As described above, according to this embodiment, a conventional electrophotographic process for forming an image on plain paper is performed using
Since the image can be formed on the C film, it is not necessary to add a large-scale dedicated image forming means for recording the image of the TC film, thereby suppressing an increase in cost and apparatus volume and a complicated image forming control system. can do.

An image forming apparatus which does not have a TC film initialization process (erasing step) for erasing a recorded image of a TC film on the way of the TC film feeding and conveying path as in the above embodiment. Then, when recording an image on a TC film, it is necessary to set the TC film initialized in advance on a paper feed tray. Therefore, in order to form an image using a TC film on which an image has been recorded in the image forming apparatus, the recorded image on the TC film must be erased in advance to initialize the TC film. However, if a TC film initializing means for initializing the TC film is newly added to the paper feed conveyance path or prepared separately,
There are inconveniences such as an increase in the number of devices, an increase in cost, and a decrease in convenience of the devices.

Therefore, in the present invention, the used T
As a means for initializing the C film, the existing fixing means 34 for fixing the toner of plain paper is used to configure the TC film so that the TC film can be initialized. Improve its convenience. That is, in order to reuse a used TC film on which an image has been recorded once, the entire surface of the TC film may be heated to a temperature at which a transparent portion (image portion) of the TC film changes to a cloudy color. Therefore, in order to initialize the used TC film in this embodiment, the same process as in the case of feeding plain paper without writing an image on the fed TC film is performed. do it.

More specifically, first, a used TC film is set on the sheet feeding tray A or the sheet feeding tray B, and the sheet feeding roller 1, the conveying roller 37, the registration driving roller 9, and the registration driven roller 40 are used. The topmost used TC film is fed and conveyed. At this time, no image signal is sent, the optical unit 5 does not write an image as a latent image on the photoconductor 10, and toner is not attached to the photoconductor 10 by the developing unit 4. As a result, the used TC film passes through the transfer / separation unit 8 without toner adhered to the film surface. Used T conveyed without toner attached
When the C film passes through the fixing unit 34, the entire surface thereof is heated by the heating roller 20 of the fixing unit 34 to a temperature at which the transparent portion (image portion) of the TC film changes to a cloudy color. Thereby, the entire surface of the TC film is initialized to be cloudy, and the used image recorded by the transparent portion and the cloudy portion is erased. In this erasing step, TC
Since no toner is attached to the film surface of the film, the TC cleaning means 24
And the blade 25 faces a state separated from the transport roller 38a. The TC film thus initialized is further transported by the transport rollers 38, guided by the discharge guide plate 28, and discharged onto the discharge tray 30 by the discharge rollers 29.

The control of the TC film initialization process as described above is performed by the overall control means of this embodiment shown in FIG.
This is performed based on the fixing unit control program shown in FIG. 3 and the heater control program shown in FIG. That is, various inputs, outputs, and control signals of the above embodiment are collectively processed by the main control unit 901 shown in FIG. 2, an operation request input to the main control unit 109 includes a setting input by an operator pressing a key from the operation unit 903 and an image information input unit 904 represented by a facsimile receiving apparatus or a host computer. There are image information and commands. Inputs for controlling this apparatus include a timing detection signal by the pre-registration sensor 31 and the paper ejection sensor 32, a temperature detection signal by a thermistor T for detecting the temperature of the heating roller 20, and a temperature detection signal in the image forming apparatus. In-machine temperature sensor 906 and the like. Outputs and control signals from the main control unit 901 are as follows:
Paper feed roller 1, registration drive roller 9, optical unit 5, developing unit 4, charging unit 6, transfer / separation unit 8, photoconductor 10, transport switching unit 12, irradiation unit 15, pressure roller 19, heating roller 20, heater 21, TC cleaning means 24, paper discharge rollers 29, and the like.

Here, a program for controlling the fixing means 34 and the heater 21 in this embodiment and various setting data necessary for executing the program are, for example, RO
M is stored in a storage unit 902 such as M, and an internal timer 905 is used to generate timing during operation. That is, the fixing unit 34 in the present embodiment is controlled based on the control flowchart shown in FIG. In FIG. 3, when the image forming apparatus starts, first, the paper feed mode of the apparatus is changed to a TC mode for feeding a TC film or a plain paper is fed by setting input from the operation unit 903 in FIG. It is determined which mode is the PP mode. Here, if it is determined that the mode is the TC mode for feeding a TC film that has been initialized in advance, the fixing unit 3
4 is moved to a position retracted from the pressure roller 19 and the heater 21 of the heating roller 20 is moved.
The fixing means 34 is controlled so that is turned off. When the control is completed, the initialized TC film is fed and conveyed as described above, a predetermined image is formed on the TC film, and an image is recorded on the TC film.

On the other hand, if it is determined in the step of judging the sheet feeding mode that the mode is not the TC mode for feeding the TC film which has been initialized in advance, first, the fixing means 34
Is moved to a position where it comes into pressure contact with the pressure roller 19 with a predetermined nip pressure and is heated. Next, depending on the setting input from the operation unit 903 in FIG. 2, the paper feeding mode of the apparatus is either the PP mode for feeding plain paper or the TC erasing mode for feeding used TC film. Judge. If it is determined that the paper feeding mode of the apparatus is the PP mode for feeding plain paper, the appropriate temperature for fixing the plain paper stored in the storage unit 902 in advance is set to a set value, It moves to the heater control shown in FIG. In this heater control, for example, PID control or the like is performed by the main control unit 901 on the basis of given setting conditions and the temperature detected by the thermistor T, and the heater 21 is turned on / off. Next, it is determined whether or not the temperature of the heater 21 is appropriate for fixing the plain paper. If the temperature is appropriate, the activation of the paper feed roller 1 is permitted. Prohibit startup. As a result, the plain paper is fed and conveyed as described above, a predetermined image is formed on the plain paper, and an image is recorded on the plain paper.

On the other hand, if it is determined from the setting input or the like from the operation unit 903 in FIG. 2 that the paper feeding mode of the apparatus is the TC erasing mode for feeding used TC film, the storage unit 902 is stored in advance. The proper temperature for erasing the stored TC film is set to a set value, and the process proceeds to the heater control shown in FIG. In this heater control, given setting conditions and
On the basis of the temperature detected by the thermistor T, the main control unit 901 performs an operation such as PID control to turn on / off the heater 21. Next, heater 2
Judgment is made as to whether or not the temperature of No. 1 is appropriate for erasing the TC film. If the temperature is appropriate, the start of the feed roller 1 is permitted. If not, the start of the feed roller 1 is prohibited. I do. As a result, the used TC film is fed and conveyed through the above-described plain paper feeding and conveying path, and the used TC film is heated to an appropriate temperature by the fixing unit 34, and the recorded image is erased. Used TC
The film is initialized.

By the way, in the above-described embodiment, an example has been described in which the calorie control for erasing the recorded image of the TC film is performed by controlling the temperature of the heat source (heater 21).
As another method, a heating roller 20 and a pressure roller 19 are used.
A method of controlling the nip pressure of the fixing device 34, a method of controlling the TC film transport speed (transport motor), or
By controlling these methods in combination, T
The heat quantity control for erasing the recorded image of the C film may be performed in the same manner as in the above embodiment.

As described above, by controlling the temperature of the heat source (heater 21), T
Optimizing the erasing temperature of the recorded image of C film by TC
The film can be initialized efficiently, and the power consumption of the heat source can be reduced.

As described above, the TC of the fixing means 34
By controlling the transport speed of the film, the TC film can be initialized efficiently by optimizing the erasing speed of the recorded image of the TC film, in addition to the above-described effects.

Further, as described above, the heat source (heater 2)
By controlling the temperature of 1), the nip pressure between the heating roller 20 and the pressure roller 19, and the conveying speed of the TC film of the fixing unit 34 in combination, the erasing temperature, the erasing pressure, and the In addition, the TC film can be initialized more efficiently by optimizing the erasing speed, and the power consumption of the heat source can be reduced.

[0033]

According to the present invention, the recorded image of the reversible thermosensitive recording film can be erased by utilizing the fixing means of the conventional electrophotographic process for forming an image on a plain paper sheet. Therefore, it is not necessary to add a new dedicated erasing means for erasing the image, and it is possible to suppress an increase in cost and apparatus volume and a complicated image forming control system.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a configuration of an embodiment of the present invention.

FIG. 2 is an overall control block diagram of an embodiment of the present invention.

FIG. 3 is a flowchart illustrating a control operation of a fixing unit according to the embodiment of the present invention.

FIG. 4 is a flowchart illustrating a control operation of a heater of a fixing unit according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Paper feed roller 2 Paper feed guide plate 4 Developing means 5 Optical unit 6 Charging means 7 Photoreceptor cleaning means 8 Transfer separation means 9 Registration drive roller 10 Photoreceptor 11 Pre-transfer guide plate 12 Transport switching means 13 Transport guide plate 14 Fixing Inlet guide plate 15 Irradiation means 16 Irradiation lamp 17 Reflector plate 18 Condenser lens 19 Pressure roller 20 Heating roller 21 Heater 22 Fixing outlet upper guide plate 23 Fixing outlet lower guide plate 24 TC cleaning means 25 Blade 26 Collection roller 27 Collection bottle 28 Discharge guide plate 29 Discharge roller 30 Discharge tray 31 Pre-registration sensor 32 Discharge sensor 34 Fixing means 35 Separation pad 36 Fan 37, 38 Transport roller 39 Fixing entrance lower guide plate 40 Register driven roller 901 Main control unit 902 Storage unit03 operation unit 904 image information input unit 905 internal timer A, B tray T thermistor

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Satoshi Muramatsu 1-3-6 Nakamagome, Ota-ku, Tokyo, Ricoh Co., Ltd. (72) Inventor Hideki Tobinaga 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (72) Masato Otani, Inventor 1-3-6 Nakamagome, Ota-ku, Tokyo Tokyo-72 Ritsuko Yasushi, Inventor Yasushi Suzuki 1-3-6, Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (56) References REAL BUSINESS 1984-91071 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B41J 2/315-2/38 B41J 2 / 435-2/48 B41M 5/26 G03G 13/20 G03G 15/20 G03G 15/22-15/24 H04N 1/23-1/31

Claims (4)

(57) [Claims] 1. An image forming means for forming an image on a plain paper sheet for image recording, and an image forming means for forming an image on a reusable reversible thermosensitive recording film initialized by heating to a predetermined temperature. And a heating and fixing device for heating and fixing an image on a plain paper sheet, comprising: a switching unit for switching the heating and fixing device between a heating state and a non-heating state. The heating and fixing device is switched by the switching unit to a heated state when the reversible thermosensitive recording film passes through the fixing device for initialization, and to a non-heated state when it passes for image formation. Image forming device for reversible thermosensitive recording film. 2. A temperature control device for controlling a temperature of a heat source of the fixing device.
An image forming apparatus for the reversible thermosensitive recording film according to the above. 3. An image forming apparatus for a reversible thermosensitive recording film according to claim 1, further comprising a conveyance speed control means for controlling a paper conveyance speed of said fixing means. 4. A fixing condition control means for controlling a combination of a temperature of a heat source of the fixing means, a sheet pressure of the fixing means, and a sheet conveying speed of the fixing means. An image forming apparatus for the reversible thermosensitive recording film according to claim 1.