Patent Publication Number: US-8994765-B2

Title: Decoloring system and control method of decoloring system

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority of U.S. Provisional Patent Application No. 61/612,214, filed on Mar. 16, 2012; the entire contents of which are incorporated herein by reference. 
    
    
     FIELD 
     Embodiments described herein relate generally to a decoloring system for erasing the color of the image formed on a paper sheet and the control method of the decoloring system. 
     BACKGROUND 
     People have developed a recording material that can have its color erased when heated over a prescribed temperature. When this recording material is adopted, by applying heat on the image printed on the paper sheet, the paper sheet can be reused. However, in order to reuse the paper sheet, it is necessary to check whether the color of the image is sufficiently erased over a certain level of soundness and whether the paper sheet is not broken. In the recent years, people have developed a decoloring system with the function in decoloring the color on the paper sheet and the function in determining whether the paper sheet can be reused. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating the configuration of the decoloring system in a first embodiment. 
         FIG. 2  is a diagram illustrating the configuration of the decoloring unit in the first embodiment. 
         FIG. 3  is a block diagram illustrating the function of the decoloring system in the first embodiment. 
         FIG. 4  is a diagram illustrating the configuration of the interconnection between the motors and the rollers in the first embodiment. 
         FIG. 5  is a reference table illustrating the relationship between the resolution and the paper sheet transporting speed in the first embodiment. 
         FIG. 6  is a reference table illustrating the relationship between the resolution and the controlled temperature of the heating roller when the decoloring process is carried out for both sides of the paper sheet in the first embodiment. 
         FIG. 7  is a reference table illustrating the relationship between the resolution and the controlled temperature of the heating roller when the decoloring process is carried out for one side of the paper sheet in the first embodiment. 
         FIG. 8  is a diagram illustrating the configuration of the table wherein the printing setting is recorded in the first embodiment. 
         FIGS. 9A to 9D  are diagrams illustrating the time series of transporting of the paper sheet in the first embodiment. 
         FIG. 10  is a diagram illustrating the configuration of the requesting GUI adopted by the user according to the first embodiment. 
         FIG. 11  is a diagram illustrating the configuration of the set-up GUI adopted by the user according to the first embodiment. 
         FIG. 12  is a flow chart illustrating the operation of the decoloring system according to the first embodiment. 
         FIG. 13  is a flow chart illustrating the set-up information acquisition process according to the first embodiment. 
         FIG. 14  is a flow chart illustrating the reuse process in the first embodiment. 
         FIG. 15  is a flow chart illustrating the reuse process in the first embodiment. 
         FIG. 16  is a flow chart of the first image read process according to the first embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     In general, the embodiment according to the disclosure will be described with reference to the drawings. In the drawings, the same reference numerals denote the same or similar portions respectively. 
     In the following, the first embodiment will be explained with reference to  FIG. 1  to  FIG. 16 .  FIG. 1  is a diagram illustrating the configuration of a decoloring system  1  of the first embodiment. Here, the decoloring system  1  uses a decolorable toner or decolorable ink or another “decolorable coloring material” to carry out “decoloring process” for the paper sheet (recording media) having an image formed on its surface. Here, the decoloring process is defined as the process for erasing the color of the image with the decolorable coloring material. The decolorable coloring material refers to the coloring agent, the developing agent, or the decoloring agent. An example of the coloring agent is leuco dye. An example of the developing agent is one or more phenol. The decoloring agent is a substance that has a mutual dissolving ability with the developing agent and has no affinity to the coloring agent when heated. The decolorable coloring material is colored due to the interaction between the coloring agent and the developing agent. When heated over the decoloring temperature, the interaction between the coloring agent and the developing agent stops, so that decoloration takes place. In the following, the decolorable coloring material will be referred as the recording material. 
     The decoloring system  1  has a paper feeding tray  2 , paper exhausting trays  3  and  4 , scanners  5  and  6 , a decoloring unit  7 , a printer  8 , a paper transporting mechanism, and an operation panel  9 . The paper transporting mechanism contains plural rollers, sensors and transporting passages. The transporting passages are defined below. The transporting passage from the roller  11  to a merging point  50  is defined as the first transporting passage; the transporting passage from the merging point  50  to a gate  51  is defined as the second transporting passage; the transporting passage from the gate  51  via the decoloring unit  7  to the merging point  50  is defined as the third transporting passage; the transporting passage from the gate  51  via a gate  53  to the paper exhausting tray  3  is defined as the fourth transporting passage; and the transporting passage from the gate  53  to the paper exhausting tray  4  is defined as the fifth transporting passage. 
     According to the first embodiment, the rollers commonly include a pair of rollers. Although not a necessity, one roller is the driving roller connected to the motor either directly or indirectly, while the other roller is a slave roller that is rotated following the driving roller. In the figure, the driving roller is indicated by a circle in a circle. 
     The paper feeding tray  2  accommodates the paper sheets subject to processing for reuse. Here, the process for reuse is defined as a series of processes including the following functions: the function of acquisition of the image data from the paper sheet before the decoloring process, the function of the decoloring process, and the function of the checkup of the decoloration and the state level of the paper sheet. The paper feeding tray  2  has a sensor  30 , a pickup roller  10 , and a roller unit  11 . The sensor  30  detects the presence/absence of the paper sheet in the paper feeding tray  2 . The pickup roller  10  transports the paper sheet to the roller unit  11 . The upper roller of the roller unit  11  is rotated in the direction for transporting the paper sheet towards the interior of the system, and the lower roller of the roller unit  11  is rotated in the direction opposite to that of the upper roller. Consequently, the roller unit  11  can transport the paper sheets one at a time. 
     In the first transporting passage, a paper sensor  31 , a roller  12  and a paper sensor  32  are arranged in order from the upstream side in the paper transporting direction. The paper sensor detects whether there is a paper sheet at the detecting position of the sensor. The paper sensor is not limited to the optical sensor. It may also be a mechanical sensor, a sonic wave-type sensor, etc. 
     In the second transporting passage, a roller  13 , a paper sensor  33 , scanners  5  and  6 , a paper sensor  34 , a roller  14 , a printer  8 , and a gate  51  are arranged in order from the upstream side in the paper transporting direction. Here, the scanners  5  and  6  each have an image sensor. The image sensor is, but is not limited to, a one-dimensional CCD line sensor. It may also be a two-dimensional CCD sensor. The image sensor receives the light emitted from a light source not shown in the figure and reflected from the surface of the paper sheet. The image sensor converts the image, wrinkles, holes, damages, etc. on the paper sheet to the image data. The scanner  5  is arranged on the side of the sheet opposite to the scanner  6 , with the second transporting passage sandwiched between them. The scanner  5  generates the image data from one side of the paper sheet at a reading position  55 . The scanner  6  generates the image data from the other side of the paper sheet at the reading position  56 . The decoloring system  1  can generate the image data from both sides of each paper sheet in a single round of the operation. 
     The printer  8  has the function of printing on one side of the paper sheet being transported. This printer  8  is, but is not limited to, an inkjet-type printer. It may also be an electrophotographic-type, a thermal-type or the like. The ink is made of the recording material. The gate  51  can switch the transporting direction of the paper sheet to either the third transporting passage or the fourth transporting passage. 
     In the third transporting passage, a paper sensor  35 , a roller  15 , a roller  16 , paper sensors  36  and  37 , a roller  17 , a decoloring unit  7 , a paper sensor  38 , rollers  18  and  19 , a paper sensor  39 , a roller  20 , and a paper sensor  40  are arranged in order. 
     In the fourth transporting passage, a roller  21 , a gate  53 , a paper sensor  41 , a roller  22 , and a paper sensor  42  are arranged in order from the upstream side in the paper transporting direction. In the fifth transporting passage, a roller  23 , a paper sensor  43 , a roller  24 , and a paper sensor  44  are arranged in order from the upstream side in the paper transporting direction. 
     The paper exhausting trays  3  and  4  accommodate the paper sheets separated after the end of the decoloring process. For example, the paper sheets that can be reused are accommodated in the paper exhausting tray  3 , while the paper sheets that cannot be reused are accommodated in the paper exhausting tray  4 . 
     The operation panel  9  has a touch panel display  84 , a tag reader  85 , and a camera  93 . Here, the touch panel display  84  displays the graphical user interface (GUI), and it receives a user&#39;s instruction from the buttons, keyboard, etc. arranged in the GUI. The tag reader  85  reads the information from a non-contact IC tag. The user information can be read from an IC card held by a user. The tag reader  85  may contain a system for reading the magnetic stripe card. The camera  93  has a two-dimensional CCD image sensor, and it can recognize the one-dimensional or two-dimensional barcode or the like. 
       FIG. 2  is a diagram illustrating the configuration of the decoloring unit. Here, the decoloring unit  7  has heating rollers  60  and  62 , pressing rollers  61  and  63 , a first heater  64 , a second heater  65 , a third heater  66 , temperature sensors  67  and  68 , and thermostats  69  and  70 . The paper sheet enters through an inlet  71  into the decoloring unit  7 , and it is exhausted through an outlet  72 . The arrow indicates the transporting direction of the paper sheet. 
     The heating rollers  60  and  62  are made of metal tubes. The heating roller  60  contains the first heater  64  inside of it. The heating roller  62  contains the second heater  65  and the third heater  66  inside of it. The first heater  64  is a halogen lamp heater with a nominal output power of 600 W. The second heater  65  and the third heater  66  each are halogen lamp heaters with a nominal output power of 300 W. The heaters are not limited to the halogen lamp heaters. They may also be ceramic heaters or inductive heaters. 
     The pressing rollers are made of silicone rubber. The pressing roller  61  is arranged at the position in contact with the heating roller  60 . The pressing roller  63  is arranged at the position in contact with the heating roller  62 . As the heating roller and the pressing roller are rotated, the paper sheet is transported through the pinch region there between. The heating roller  62  is arranged on the downstream side in the paper transporting direction in comparison with the heating roller  60 . The heating roller  60  heats up one side of the paper sheet, and the heating roller  62  heats up the other side of the paper sheet. That is, the heating roller  60  is arranged on the side opposite to the heating roller  62  with respect to the third transporting passage. 
     Abutting the surface of the heating roller  64 , the temperature sensor  67  and the thermostat  69  are arranged. Abutting the surface of the heating roller  66 , the temperature sensor  69  and the thermostat  70  are arranged. The temperature sensors  67  and  68  detect the surface temperature of the heating rollers, respectively. The thermostats  69  and  70  cut off the power supply to any of the heaters  64  to  66  when the heating roller is heated over a prescribed temperature level. 
       FIG. 3  is a block diagram illustrating the function of the decoloring system. Here, a controller  80  of the decoloring system  1  has a CPU (central processing unit) or another processor  81  and a memory  82 . The memory  82  contains ROM (read-only memory) and RAM (random access memory), etc. Here, the ROM is for storing the programs for controlling the controller  80 . The RAM is for temporarily storing the programs and data files that can be used by the processor  81 . The controller  80  is connected via a bus  100  to an HDD (hard disk drive)  83 , the operation panel  9 , a heater controller  86 , a transporting controller  87 , a scanner  5 , a scanner  6 , an image processing section  91 , a printer  8 , and a communication interface  92 , and it can carry out mutual communication with these devices. 
     The HDD  83  stores the image data generated by the scanner  5  and the scanner  6 . One may also adopt a flash memory or another nonvolatile memory in place of the HDD. The operation panel  9  has a touch panel display  84 , a tag reader  85 , and the camera  93 . The controller of the operation panel  9  controls the various devices according to the instructions from the controller  80 . 
     The heater controller  86  is connected to a first heater  64 , a second heater  65 , a third heater  66 , the temperature sensors  67  and  68 , and the thermostats  69  and  70 . Corresponding to the instructions from the controller  80  and the outputs of the various temperature sensors, the heater controller  86  controls the first heater  64 , the second heater  65 , and the third heater  66 . 
     The transporting controller  87  controls the motors M 1  to M 5 , the electromagnetic clutch  88 , the gate switching section  89 , and the paper feeding detecting section  90 . The motors M 1  to M 5  provide driving forces to the plural rollers. The electromagnetic clutch  88  controls the transmission of the driving force from the motor to the roller. The gate switching section  89  switches the stop positions of the gates  51  and  53 . The paper feeding detecting section  90  receives the output from the paper sensors  30  to  44  and detects the position of the paper sheet in the decoloring system  1 . 
     The image processing section  91  converts the image data generated by the scanner  5  and the scanner  6  to the image file in JPEG (Joint Photographic Expert Group) format, one of the formats of the image file, and stores them in the HDD  83 . The image processing section  91  checks the state of the paper sheet from the image data and determines whether the paper sheet can be reused. The image processing section  91  is an ASIC (Application Specific Integrated Circuit). However, this is not exclusive. The programs for the execution in the controller  80  are contained. 
     The communication interface  92  is connected to the decoloring system  1  and the server  95  via LAN (Local Area Network), WAN (Wide Area Network), or the like. The server  95  contains a controller  96  and an HDD  97 . The server  95  receives the image data stored in the HDD  83  and has them stored in the HDD  97 . Also, the server  95  receives from the decoloring system  1  the read ID from the tag reader  85  and the camera  93 ; on the basis of the received read ID, it sends the data to the decoloring system  1 . 
       FIG. 4  is a diagram illustrating the configuration of the interconnection between the motors and the rollers. In  FIG. 4 , the plural gears connecting the motors to rollers are not shown. The motor M 1  is connected to the rollers  13  and  14 . The motor M 2  is connected to the rollers  15  and  16 . The motor M 3  is connected to the roller  17 , the heating rollers  60  and  62 , the roller  18 , and the electromagnetic clutch  88 . The electromagnetic clutch  88  is connected to the roller  19  and the one-way clutch  99 . The one-way clutch  99  is connected to the roller  20 . When the motor M 3  is driven to rotate, the transporting controller  87  controls the electromagnetic clutch  88 , so that the rollers  19  and  20  can be stopped. The one-way clutch  99  rotates idling when the rotation speed of the roller  20  is over a prescribed level. The motor M 4  is connected to the rollers  11  and  12 . The motor M 5  is connected to the rollers  21  to  24 . 
       FIG. 5  is a reference table illustrating the relationship between the resolution and the paper sheet transporting speed. For each value of the first resolution, the speed reference table  110  defines the second resolution, the first read speed, the erasing speed, and the second read speed. The first resolution is the resolution setting for the scanners  5  and  6  for storing the image data on the paper sheet. The user may use the operation panel  9  to select the first resolution. “NON” indicates that the storage of the image has not been carried out. 
     The second resolution is the resolution setting for the scanners  5  and  6  for acquiring the image data of the paper sheet subject to the decoloring process. The second resolution is a resolution for determining whether the paper sheet can be reused. According to the first embodiment, it is possible to select from 2 resolutions, that is, 150 dpi and 200 dpi. Corresponding to the precision of the determination regarding whether the paper sheet can be reused by the image processing section  91 , the second resolution is set. 
     The first read speed V 1  is the speed set for the sheet moved by the rollers associated with the motors M 1  and M 3  when the image data of the paper sheet are generated at the first resolution by the scanners  5  and  6 . The erasing speed VE is the speed setting for the sheet driven by the rollers associated with the motor M 3  when the paper sheet is transported in the third transporting passage containing the decoloring unit  7 . The second read speed V 2  is the speed setting for the sheet driven by the rollers associated with the motor M 1  when the image data of the paper sheet are generated at the second resolution by the scanners  5  and  6 . As the first resolution is set to a higher value, the first read speed V 1  and the erasing speed VE are set lower. The erasing speed VE is set to be lower than the first read speed V 1  at all of the values of the first resolution. At all of the values of the first resolution, the second read speed is set at a prescribed speed matching the second resolution. 
       FIG. 6  is a reference or look up table illustrating the relationship between the resolution and the control temperature of the heating roller when the decoloring process is carried out for both sides of the paper sheet. A temperature reference table  111  is taken as reference by the controller  80  and the heater controller  86  when there is an instruction for the execution of the decoloring process on both sides of the paper sheet. For each value of the first resolution, the temperature reference table  111  settings the ON/OFF information of the first, the second and the third heaters, the control temperature T 1  of the heating roller  60 , and the control temperature T 2  of the heating roller  62 . At all of the values of the first resolution, the control temperature T 1  of the heating roller  60  is set higher than the control temperature T 2  of the heating roller  62 . As the first resolution is set higher, the control temperatures T 1  and T 2  are set lower. This is for setting a lower erasing speed VE to match the first resolution. When the control temperatures T 1  and T 2  are high and the erasing speed VE is low, a heat quantity more than what is required by the paper sheet is applied. As this heat warms the scanners  5  and  6 , the scanners  5  and  6  become unstable under the heat influence. According to this application example, the control temperature and the paper sheet transporting speed are selected to ensure that the decoloring process is carried out reliably without influence on the operation of the scanners  5  and  6 . 
     The ON/OFF information of the heater is the information for setting the corresponding heater on/off when the decoloring process is carried out. The heater controller  86  determines whether the power is supplied to the first, the second and the third heaters in the decoloring process. 
       FIG. 7  is a table illustrating the relationship between the resolution and the control temperature of the heating roller when the decoloring process is carried out for one side of the paper sheet. A temperature reference table  112  is used as a reference by the controller  80  and the heater controller  86  when the user instructs the execution of the decoloring process for one side of the paper sheet. For each value of the first resolution, the temperature reference table  112  sets the ON/OFF threshold of the first, second and third heaters, the control temperature T 1  of the heating roller  60 , and the control temperature T 2  of the heating roller  62 . When the first resolution is 150, 200, and 300 dpi, the second and third heaters are not turned on; as a result, the control temperature T 2  is not set. 
       FIG. 8  is a diagram illustrating the configuration of the table for recording the setting up of printing. The storage area of the printing set up table  113  contains HDD  96  of the server  95 . However, this is not limited to this. One may also adopt a scheme in which it is stored in the HDD  83  of the decoloring apparatus  1  or the device connected to another network. The field name of the printing set up table  113  contains, but is not limited to, the document ID, the double-sided/single-sided setting up, the N-in-1 setting up, and the user ID. It also contains the standard setting up of printing for the printer, such as the size of the paper sheet, etc., the page number of 1 job, the number of the copies for printing, etc. 
     The document ID is the ID (Identification) data given to each job printed by the printer. Each job is specified by this document ID. The double-sided/single-sided set up is the set up information pertaining to whether both sides of the paper sheet are in use when printing is carried out by the printer. N-in-1 indicates the number of the originals printed on one side of 1 page. The color indicates printing in monochromic, single color or full color. The user ID indicates the sender of the printed data. 
     The document ID is printed at the corner of the paper sheet when a sheet is printed by the printer. The printed document ID is, but is not limited to, characters. It may also be a one-dimensional or two-dimensional barcode. When a two-dimensional barcode is printed, the printing set up data related to the document ID are contained in the two-dimensional barcode. 
       FIGS. 9A to 9D  show diagrams illustrating the transportation of the paper sheet shown in time sequence. As shown in  FIG. 9A , the paper sheet P 1  passes through the first transporting passage and the second transporting passage, and it is guided by the gate  51  to the third transporting passage. The motors M 1  and M 2  drive the rollers to transport a sheet at the first read speed V 1 . The motor M 3  drives the rollers to transport a sheet at the erasing speed VE. As the paper sheet P 1  is transported, the scanners  5  and  6  acquire the images on the two sides of the paper sheet P 1  at the first resolution. As the front end of the paper sheet P 1  is detected by the sensor  37 , the motor M 2  drives the rollers to transport a sheet at the erasing speed VE. The rollers  15  and  16  transport the paper sheet P 1  to the decoloring unit  7 . The paper sheet P 2  stands by before the merging point  50 . At the time when the trailing end of the paper sheet P 1  passes the paper sensor  34 , the paper sheet P 2  is transported from the first transporting passage to the second transporting passage. 
     As shown in  FIG. 9B , the paper sheet P 1  passes the decoloring unit  7 , and it is transported in the third transporting passage at the erasing speed VE until the front end is detected by the paper sensor  40 . After the image data is read by the scanners  6  and  7  and until the front end of the paper sheet P 2  is detected by the sensor  37 , the paper sheet P 2  is transported at the first read speed V 1 . At the time when the front end of the paper sheet P 1  is detected by the paper sensor  40 , the transporting controller  87  checks whether the paper sheet P 2  is not detected by the sensors  33  and  34 . When the paper sheet P 2  is detected by the sensors  33  and  34 , the transporting controller  87  turns off the electromagnetic clutch  88 , so that the rollers  19  and  20  are stopped. When the paper sheet P 2  is not detected by the sensors  33  and  34 , the motor M 1  has its speed changed so that the transporting speed of the rollers  13  and  14  becomes the rotational velocity needed to transport a sheet at the second read speed V 2 . The paper sheet P 3  then stands by before the merging point  50 . 
     As shown in  FIG. 9C , when the sensors  33  and  34  do not detect the paper sheet P 2 , the transporting controller  87  turns on the electromagnetic clutch  88 , and the paper sheet P 1  is transported at the erasing speed VE to the second transporting passage. As the front end of the paper sheet P 1  enters the roller  13 , the paper sheet P 1  is transported at the second read speed V 2 . Because the second read speed V 2  is higher than the erasing speed VE, the roller  20  is rotated at a speed higher than the erasing speed VE. The power from the motor M 3  to the roller  20  is cut off by the one-way clutch  99 , so that the roller rotates in an idling state. The scanners  5  and  6  generate the image data of the paper sheet P 1  at the second resolution. The paper sheet P 2  is transported at the erasing speed VE to the decoloring unit  7 . The paper sheet P 3  stands by before the merging point  50 . The gate  51  is setting at the position for guiding the paper sheet P 1  to the fourth transporting passage. 
     As shown in  FIG. 9D , when the rear end of the paper sheet P 1  is detected by the paper sensor  34 , the transporting controller  87  adjusts the transporting speed of the rollers  13  and  14  so that they rotate at the first read speed V 1 . As the front end of the paper sheet P 1  is detected by the paper sensor  41  or the paper sensor  43 , the gate  51  is set at the position for guiding the paper sheet to the third transporting passage, and the paper sheet P 3  is transported to the second transporting passage. At this time, the paper sheet P 3  is sequentially detected by the sensors  33  and  34 . When the front end of the paper sheet P 2  is detected by the paper sensor  40 , the transporting controller  87  turns off the electromagnetic clutch  88 , so that the rollers  19  and  20  are stopped. When the paper sensor  34  does not detect the paper sheet P 3 , the transporting controller  87  turns on the electromagnetic clutch  88 , so that the paper sheet P 2  is transported into the second transporting passage. Then, until the reuse process ends for all of the paper sheets, the operation is continued. 
       FIG. 10  is a diagram illustrating the configuration of the requesting GUI for use by a user. Here, a requesting GUI (graphical user interface)  130  contains an area  131 , a camera button  132 , an execution (Enter) key  133 , and a skip key  134 . Here, the area  131  is an area for receiving the request for the input of the document ID. The user can use a software keyboard not shown in the figure to input the document ID printed on the paper sheet. 
     The camera button  132  is for giving instructions to the camera  93  to acquire the image data. As the user presses the camera button  132 , the user can have the document ID, the one-dimensional barcode or the two-dimensional barcode printed on the paper sheet moved to a position near the camera  93 . The controller  80  analyzes the image obtained by the camera  93 , and it can obtain the document ID and other printing set-up information from the character, the one-dimensional barcode or the two-dimensional barcode. 
     The Enter key  133  checks the data input to the area  131  or the data acquired by the camera  93 . The skip key  134  is used to omit the input of the requesting GUI  130 . 
       FIG. 11  is a diagram illustrating the configuration of the set-up GUI adopted by the user. The set-up GUI  120  is generated by the controller  80 , and it is displayed on the touch panel display  84 . The plural buttons of the set-up GUI  120  can be selected by the user. The controller  80  receives the selected result from the user and executes the reuse process. The user may use the touch panel display  84 , the tag reader  85  or the camera  93  to log in the decoloring system  1 . When the user is specified, the user name is displayed on the set-up GUI  120 . 
     The set-up GUI  120  contains region  121 , region  122 , and region  123 . The region  121  is provided for the designation of the storage of the data, and it has a YES button and a NO button indicating yes/no for the instruction of storing the image data. When the user selects the YES button, it indicates that it is possible to select plural resolutions and the storage format of the image data. As the initial value, the set-up GUI  120  for which the YES button is selected is displayed on the touch panel display  84 . This initial value executes the decoloring process for the paper sheet so that it works efficiently when the user fails to check on the set-up. 
     The region  122  is provided for selecting one side or both sides of the paper sheet. Corresponding to the button selected by the user, the heater controller  86  selects either of the reference tables  111  to  112 . The region  123  is a region for assigning the address and file name for the storage of the image data generated by the scanners  5  and  6 . The user can directly input the address of the HDD  83  and the HDD  97  in the decoloring system  1  and the HDD in the other network. The user can use the select button to assign the address easily. 
     The start button is a button for initiating the reuse process. The cancel button has the function of resetting the content selected by the user to the initial value. 
       FIG. 12  is a flow chart illustrating the operation of the decoloring system  1 . As the user ID is input from the operation panel  9 , the controller  80  determines whether the user ID is correct and gives permission to the user to log in the system (Act  11 ). The controller  80  starts the set-up information acquisition process routine and acquires the necessary information from the operation panel  9  (Act  12 ). The set-up information acquisition process routine will be explained in detail later. 
     The controller  80  checks whether the user instructs that the image data be stored (Act  13 ). When the storage of the image data is instructed by the user by the operation panel  9 , the controller  80  acquires the first resolution setting at the same time, and it sets the first resolution for the scanners  5  and  6  (Act  14 ). When the user does not instruct that the image data be stored, the controller  80  sets the first resolution as “NON.” The controller  80  reads the reference table  110 , and it acquires the data of the V 1 , VE, and V 2  on the basis of the setting of the first resolution (Act  15 ). The transporting controller  87  sets V 1  for the motors M 1 , and M 2  and sets VE for the motor M 3  (Act  16 ). 
     On the basis of the set-up information of the single-sided/double-sided that has been established, the temperature reference table  111  or the temperature reference table  112  is selected by the controller  80 . On the basis of the first resolution setting, the controller  80  acquires the control temperature data from the selected temperature reference table (Act  17 ). The controller  80  then checks whether the control temperature T 2  is properly set (Act  18 ). When the control temperature T 2  is set, the heater controller  86  starts turning on the first, second and third heaters (Act  19 ). 
     The heater controller  86  keeps the first heater ON until the temperature T 1 ′ that is detected by the temperature sensor  67  exceeds the control temperature T 1 . The heater controller  86  keeps the second and third heaters ON until the temperature T 2 ′ that is detected by the temperature sensor  68  rises above the control temperature T 2 . 
     In Act  18 , when the control temperature T 2  is not set, the heater controller  86  starts turning on the first heater (Act  21 ). The first heater is kept ON until the temperature T 1 ′ that is detected by the temperature sensor  67  exceeds the control temperature T 1  (Act  22 ). When T 1 ′ and T 2 ′ become over a prescribed temperature, the controller  80  reads the ON/OFF information of the first to third heaters from the temperature reference table. The heater controller  86  determines which heater should be turned on during the decoloring process on the basis of the ON/OFF information (Act  23 ). When all of the information has been set, and the warming-up of the decoloring system  1  ends, the controller  80  carries out the reuse process (Act  24 ). After the end of all of the reuse processes, the image data generated by the scanners  5  and  6  are stored at the assigned address in the network (Act  25 ). The flag indicating the end of the document ID and the reuse process is sent to the server  96 . 
       FIG. 13  is a flow chart illustrating the set-up information acquisition process. In Act  11 , when the user is permitted to log in to the decoloring system  1 , the controller  80  displays the requesting GUI  130  on the touch panel display  84  (Act  61 ). The controller  80  then checks whether the skip button  134  is pressed by the user (Act  62 ). If the skip button  134  is pressed, the set-up GUI  120  is displayed on the touch panel display  84  (Act  67 ). 
     If the skip button  134  is not pressed by the user, the controller  80  checks whether the camera button  132  is pressed (Act  63 ). If the camera button is not pressed, the controller  80  acquires the document ID that has been input into the area  131  (Act  64 ). Then, the controller  80  sends the document ID to the server  95  and acquires the printing set-up information related to the document ID (Act  65 ); it also stores the single-sided/double-sided information of the printing set-up information (Act  66 ). When the user presses the Enter button  132 , the controller  80  displays the set-up GUI  120  on the touch panel display  84  (Act  67 ). 
     In Act  63 , as the user presses the camera button  132 , the camera  93  generates the image data. The generated image data are sent to the controller  80 . The controller  80  then extracts the document ID from the image data (Act  68 ). The controller  80  then checks whether the printing set-up information is contained (Act  69 ). When the printing set-up information is contained in the image data, the controller  80  goes to Act  66 . When the printing set-up information is not contained in the image data, the controller  80  sends the document ID to the server  96 , and it goes to Act  65 . 
     In Act  67 , when the set-up GUI  120  is displayed on the touch panel display  84 , the user may carry out the setting up of the data storage, the setting up of the double-side/single-side, and the selection of the file name and the storage address. As the user presses the start button, the controller receives the setting up data about the data storage, the setting up of the double-side/single-side, the file name, and the storage destination (Act  70 ). In Act  65 , if the double-sided/single-sided set up received by the server  95  is different from the selection by the user in Act  70 , the set-up of double-side/single-side provided by the user is given the priority. 
       FIGS. 14 and 15  are flow charts illustrating the reuse process. The reuse process is carried out one paper sheet at a time. In practice, however, controller  80  may carryout the same or similar processes in parallel for the various paper sheets under the process. 
     After the initiation of Act  24 , the rollers  10 ,  11 , and  12  pickup the paper sheet in the paper feeding tray  2  and transport it into the first transporting passage (Act  30 ). The transporting controller  87  checks whether the sensors  33  and  34  in the second transporting passage detect the paper sheet (Act  31 ). When the sensors  33  and  34  do not detect the paper sheet, the transporting controller  87  has the motor M 4  turned on and has the paper sheet in the first transporting passage transported to the second transporting passage (Act  32 ). The controller  80  checks whether the storage of data is assigned by the set-up GUI  120  (Act  33 ). When the user assigns the storage of the image data, the first image read process is executed (Act  34 ). The first image read process will be explained in detail later. 
     The transporting controller  87  controls the motor M 2  so that it operates to move the sheet at the first read speed V 1  until the front end of the paper sheet is detected by the sensor  36  (Act  35 ). When the sensor  36  detects the front end of the paper sheet, the transporting controller  87  controls the motor M 2  so that the paper sheet transporting speed is changed to the erasing speed VE (Act  36 ). As the motor M 2  changes the paper sheet transporting speed to the erasing speed VE, the paper sheet is transported to the decoloring unit  7 , and the decoloring process is carried out (Act  37 ). While the sensor  36  detects the paper sheet, the motor M 2  has the paper sheet transporting speed kept at VE (Act  38 ). 
     When the sensor  36  no longer detects the paper sheet, the transporting controller  87  changes the motor M 2  so that the speed of a sheet becomes the first read speed V 1  (Act  39 ). The transporting controller  87  waits for the detection of the front end of the paper sheet that the paper sensor  40  has passed the decoloring unit  7  (Act  40 ). When the paper sensor  40  detects the front end of the paper sheet, the transporting controller  87  checks whether the sensors  33  and  34  detect another paper sheet (Act  41 ). When the sensors  33  and  34  detect another paper sheet, the transporting controller  87  turns off the electromagnetic clutch, so that the paper sheet in the third transporting passage is stopped (Act  42 ). 
     When the sensors  33  and  34  do not detect another paper sheet, the transporting controller  87  controls the motor M 2  to adjust it to the second read speed V 2  (Act  43 ). The electromagnetic clutch is turned on, and the paper sheet in the third transporting passage is transported to the second transporting passage. The scanners  5  and  6  generate the image data from both sides of the paper sheet at the second resolution (Act  45 ). The image processing section  91  analyzes the image data and determines whether the paper sheet can be reused (Act  46 ). 
     When the paper sheet can be reused, the paper sheet is transported to the paper exhausting tray  3  (Act  47 ). When the paper sheet cannot be reused, the paper sheet is transported to the paper exhausting tray  4  (Act  48 ). When there is paper sheet in the paper feeding tray  3 , the controller  80  returns to Act  30 . When there is no paper sheet in the paper feeding tray  3 , the controller  80  sends the image generated by the scanners  5  and  6  to the assigned address on the network, and the entire process comes to an end. 
       FIG. 16  is a flow chart illustrating the first image read process. As the first image read process is started, the images on both sides of the paper sheet are read by the scanners  5  and  6  to acquire the image data (Act  81 ). The image processing section  91  analyzes the information about the prescribed position of the image data and checks whether the document ID is contained (Act  82 ). If the document ID is not contained in the image data, this flow comes to an end. 
     When the document ID is contained in the image data, the controller  80  sends the document ID to the server  95 , and it acquires the printing set-up data related to the document ID (Act  83 ). The controller  80  then checks whether the double-sided/single-sided information set in Act  17  is different from the double-sided/single-sided information acquired in Act  83  (Act  84 ). If the two information pieces are the same, this flow comes to an end. When the information pieces are different, the data acquired in Act  83  is given priority, and the controller  80  reads the temperature reference table  111  or  112 . The heater controller  86  reads the values of the control temperatures T 1  and T 2  from the resolution that has been set and changes the values of T 1  and T 2  (Act  85 ). 
     The decoloring system  1  in the embodiment can be controlled to have the optimum paper sheet transporting speed and the temperature of the heating rollers on the basis of the presence/absence for storing of the image data, the resolution, and the double-sided/single-sided information as setting by the user. As the paper sheet is not excessively heated by the decoloring unit, it is possible to cut the power consumption. Also, it is possible to alleviate the adverse influence of the heat of the paper sheet on the scanners. 
     According to the first embodiment, the controller  80 , the heater controller  86 , and the transporting controller  87  in the decoloring system  1  work together to control the decoloring system  1 . The various functions of these controllers can also be carried out under the control of a single controller. Also, one may adopt a configuration wherein the various functions are executed by the plural controllers including the server  95  and other controllers in the network and the controllers in the decoloring system  1 . 
     The various functions may also be carried out by ASIC or another hardware circuit and they may also be carried out by the program executed by the CPU in the controller. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and they are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.