JP2002361915A - Rewrite printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that an error is generated in an actual medium surface temperature because an erase head temperature is controlled by only a thermistor in the head, that a printing process time is elongated or an apparatus is enlarged due to the need of transferring a printing medium between the erase head and a printing head at a low velocity, stopping the transfer for a fixed time, or increasing a transfer distance between the erase head, and that the printing head because printing cannot be started before the printing medium becomes a constant or lower temperature. SOLUTION: A noncontact type temperature sensor is set between the erase head and the printing head. An erase operation is carried out while a temperature control to the erase head is executed on the basis of a detect temperature of the noncontact type temperature sensor. A printing operation is started when the surface temperature of the printing medium becomes the constant or lower temperature. Alternatively, after the erase operation by the erase head, the printing operation is started after the printing medium is forcedly gradually cooled by a heat sink when the surface temperature becomes the constant or lower temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rewritable printing medium (hereinafter referred to as a "rewritable printing medium") capable of repeating printing and erasing a fixed number of times.
It is called medium. The present invention relates to a rewritable printing apparatus that performs printing and erasing by using) and that can perform erasing and printing reliably and at high speed.

[0002]

2. Description of the Related Art FIG. 10 is a cross sectional view showing the structure of a conventional rewrite printing apparatus. The rewrite printing apparatus main body 1 includes an erasing head 2, a print head 3, a medium insertion guide 4, a medium conveyance path 5, respective medium conveyance rollers 6 to 10, and a medium 11.

The erasing head 2 is an erasing head for erasing an image printed on the medium 11 based on a printing / erasing principle described later, and the printing head 3 is a printing head for printing on the medium 11 and a medium insertion guide 4. Is a guide for inserting the medium 11 from an insertion opening (not shown) and inserting the medium up to the position just before the medium transport roller 6. The medium transport path 5 is a transport path for sequentially transporting the medium 11 of the medium insertion guide 4.
Is a conveyance roller that bites the medium 11 inserted by the medium insertion guide 4 and conveys it along the medium conveyance path 5;
The medium conveyance roller 7 is a conveyance roller that sucks the medium 11 conveyed by the medium conveyance roller 6, and the medium conveyance roller 8 is a conveyance roller that conveys the medium near the erasing head by the erasing operation. Is a transport roller that transports the medium near the print head 3 by a printing operation.
Is a conveying roller for discharging the toner. These transport rollers are driven to rotate by a gear (not shown) or the like by driving a motor of a control system, which will be described later, and transport the medium.

[0004] Here, as shown in FIG.
One side or both sides of transparent support 31 (both sides in this example)
Then, a recording layer 32 comprising a group exhibiting a color developing property to the leuco material by the action of the leuco dye and heat and a group having a group exhibiting a color reducing property in the same molecule, a coloring agent and a binder are formed. A protective layer 33 such as a protective layer for improving durability, an ultraviolet protective layer, or a protective layer for abrasion resistance is laminated on the surface as required.

In general, a leuco dye thermally reacts with a phenolic compound to open the lactone ring of the leuco dye and change its color from colorless to colored. However, the colored compound having the lactone ring opened returns to a colorless compound which is the original lactone ring upon closure of a basic substance upon touching the basic substance.

As described above, due to the reversibility of the color-reducing agent and the leuco dye, the color-reducing agent turns the colorless leuco dye into a colored compound by opening the lactone ring only by controlling the heat energy, or by closing the ring to form a colorless compound. It is used as a rewritable recording medium utilizing the property of being able to return to a leuco dye a plurality of times.

FIG. 2 shows an example of the characteristics of the above-described rewritable medium. In this figure, the horizontal axis is the temperature of the medium, and the vertical axis is the optical density representing the color density. The larger the numerical value, the higher the color development. The solid line a indicates the optical density when gradually cooled at that temperature, and the broken line b indicates the optical density when rapidly cooled at that temperature. For example, when quenched from the temperature of the point D or more, the optical density is high due to the characteristic of b in the figure, and the color is developed.
Contrast can be provided at a temperature between point D and point E. Further, when the temperature is gradually cooled at a temperature equal to or higher than the point A, the optical density becomes low due to the characteristic shown in FIG.

On the other hand, although not shown in FIG. 10, the control system 200 comprises a control unit 101, a motor drive circuit 102, and a medium transport motor 103 as shown in FIG.
Is connected to the control unit 101, and data to be printed by the rewrite printing apparatus is transmitted to the control unit 101. The control unit 101 controls the operation of the rewrite printing apparatus, and includes a microprocessor and the like. The control unit 101 is connected to the motor drive circuit 102, is connected to the outputs of a plurality of medium detection sensors 104 attached near the medium transport path 5, and has the motor drive circuit 102 rotate each transport roller. The medium transport motor 103 to be driven is connected.

With the configuration of the control system 200 described above, the motor drive is controlled based on the detection signal of each of the medium detection sensors 104, and the medium is conveyed, erased, and printed.

Hereinafter, the operation of the conventional rewrite printing apparatus will be described with reference to the flowchart of FIG. First, in step S101, the medium transport motor 103 is turned on, and each medium transport roller is driven to transport the medium 11 to the erasing head 2. Then, before the medium 11 reaches the erasing head 2, the erasing head 2 is turned on in step S102, the temperature is controlled by a thermistor in the erasing head so that the temperature becomes higher than the point A in FIG. 2, and the erasing head is heated. When the medium 11 comes near the erasing head, the erasing head 2 is brought into contact with the medium 11.

In step S103, the erasing operation is performed until the entire medium 11 has passed the erasing head.
If it is determined that the medium 11 has been completely erased and the medium 2 has passed the erasing head 2 in step S103, the erasing head 2 is turned off in step S104, and
After turning off the medium transport motor 103 in step 05 and stopping the transport for a predetermined time in step S106 for slow cooling, or slowly transporting the medium in consideration of the slow cooling time, the medium transport motor 103 in step 107 The medium 103 is conveyed to the print head 3 with the normal drive 103, the print head is turned on in step 108, the printing process is performed in step 109, the print head is turned off in step 110, and the process proceeds to step 111. To eject the media.

The printing process is an operation for printing with a general thermal head, and the temperature of the head at this time is shown in FIG.
The printing can be performed by printing as a point D or more. In other words, when heating the area of the medium to be erased as a surface to a constant temperature as in the case of erasing, it takes time to gradually cool down, but in the case of printing, heat is applied to the medium surface at only one point of the head, After the printing, it is rapidly cooled, and the characteristic becomes the characteristic of the point D in FIG. 2B, so that the optical density can be increased.

[0013]

However, as described above, in the conventional rewritable printing apparatus, the erasing head 2 is not used.
Is controlled only by the thermistor in the head, there is a problem that an error occurs between the medium surface temperature to be set and the actual medium surface temperature. Further, since printing cannot be started until the temperature of the medium 11 becomes lower than a certain temperature, the medium is conveyed at a low speed between the erasing head 2 and the printing head 3 or the medium is stopped between the erasing head 2 and the printing head 3 for a certain time.
Alternatively, it is necessary to take measures such as lengthening the transport distance between the erasing head 2 and the printing head 3 and wait for the temperature of the medium to drop. Therefore, there has been a problem that the printing processing time becomes longer or the apparatus becomes larger. . Further, when a sensor component having a heat capacity is arranged between the erasing head 2 and the print head 3, there is a problem that a portion where the temperature decreases due to the contact between the sensor component and the medium 11 occurs, and printing remains in the portion where the temperature decreases. there were.

[0014]

According to an embodiment of the present invention, the present invention employs the following structure to solve the above-mentioned problems.

That is, in the first invention, a recording layer which exhibits a color developing property by being rapidly cooled after heating at a first temperature and a discoloration property by gradually cooling after heating at a second temperature is provided on the surface of the support. In a rewritable printing apparatus that performs printing using a medium-type rewritable recording medium as a print medium, a first non-contact type temperature sensor is disposed downstream of an erasing head.
The temperature of the erasing head is controlled based on the temperature detected by the non-contact type temperature sensor, and the printing operation is performed when the medium surface temperature becomes equal to or lower than the second temperature based on the temperature detected by the first non-contact type temperature sensor. Start.

According to a second aspect of the present invention, there is provided a medium having a recording layer on a support surface, which exhibits a color developing property by being rapidly cooled after heating at a first temperature, and having a fading property by gradually cooling after heating at a second temperature. In a rewritable printing apparatus that performs printing using a linear rewrite recording medium as a print medium, a first non-contact temperature sensor is arranged near an erasing head, and a second non-contact temperature sensor is arranged near a print head. The erasing head is controlled based on the temperature detected by the first non-contact type temperature sensor. When the temperature becomes equal to or lower than the second temperature based on the temperature detected by the second non-contact type temperature sensor, the printing operation is started.

According to a third aspect of the present invention, there is provided a medium having a recording layer on a support surface, which exhibits a color developing property by being rapidly cooled after being heated at a first temperature, and having a fading property by being gradually cooled after being heated at a second temperature. In a rewritable printing apparatus that performs printing using a rewritable recording medium as a printing medium, a heat sink is arranged at a stage subsequent to the erasing head, and the heat sink is turned off when the detected temperature of the first non-contact type temperature sensor becomes equal to or lower than the first temperature. The printing medium is allowed to cool slowly.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. Elements common to the drawings are denoted by the same reference numerals.

First Embodiment FIG. 1 is a cross-sectional view showing the configuration of a rewrite printing apparatus according to the first embodiment. The rewrite printing apparatus main body 1 includes an erasing head 2, a printing head 3, a medium insertion guide 4, a medium transport path 5,
Each of the medium transport rollers 6 to 10, a medium 11 and a non-contact type temperature sensor 12 are provided.

The erasing head 2 is an erasing head for controlling the temperature of the erasing head by a thermistor (not shown) in the erasing head and erasing an image printed on the medium 11 in accordance with an erasing principle described later. Is a print head that controls the temperature of the print head by a thermistor (not shown) and prints on the medium 11 in accordance with a printing principle described later. A non-contact type temperature sensor 12 is disposed downstream of the erase head 2 and has a surface temperature of the medium 11. The medium insertion guide 4 is a guide that inserts the medium 11 from an insertion opening (not shown) and inserts the medium up to just before the medium conveyance roller 6.
Is a conveyance path for sequentially conveying the media 11 of the medium insertion guide 4, and the medium conveyance roller 6 is a conveyance roller that bites the medium 11 inserted by the medium insertion guide 4 and conveys the medium 11 along the medium conveyance path 5. The medium conveyance roller 7 is a conveyance roller that sucks the medium 11 conveyed by the medium conveyance roller 6, and the medium conveyance roller 8 is a conveyance roller that conveys the medium near the erasing head by the erasing operation. Is a transport roller that transports the medium near the print head 3 by a printing operation, and the medium transport roller 10 is a transport roller that discharges the medium 11 to an outlet (not shown). These transport rollers are driven to rotate by a gear (not shown) by a motor of a control system described later, and transport the medium 11.

Here, the medium 11 used in the present invention is:
As shown in FIG. 4, on one or both sides of the transparent support 31 (both sides in the example of this figure), a group exhibiting color development to the leuco material by the action of the leuco dye and heat, and exhibiting a color-reducing property. A recording layer 32 composed of a color-reducing agent and a binder, which are compounds having a group in the same molecule, is formed, and a protective layer for improving the durability, an ultraviolet protective layer, or protection for abrasion is formed on the surface thereof as required. A protective layer 33 such as a layer is stacked. The support 11 may be a synthetic resin film, and a PET material is preferable in consideration of durability and resource properties.

In general, the leuco dye thermally reacts with the phenolic compound to open the lactone ring of the leuco dye and change its color from colorless to colored. However, the colored compound having the lactone ring opened returns to a colorless compound which is the original lactone ring upon closure of a basic substance upon touching the basic substance.

As described above, due to the reversibility of the color-reducing agent and the leuco dye, the color-reducing agent opens the lactone ring of the colorless leuco dye only by controlling the heat energy to form a colored compound, or closes the colorless leuco dye to form a colorless compound. It is used as a rewritable recording medium utilizing the property of being able to return to a leuco dye a plurality of times.

FIG. 2 shows an example of the characteristics of the above-described rewritable medium. In this figure, the horizontal axis is the temperature of the medium, and the vertical axis is the optical density representing the color density. The larger the numerical value, the higher the color development. The solid line a indicates the optical density when gradually cooled at that temperature, and the broken line b indicates the optical density when rapidly cooled at that temperature. For example, when quenched from the temperature of the point D or more, the optical density is high due to the characteristic of b in the figure, and the color is developed.
Contrast can be provided at a temperature between point D and point E. Further, when the temperature is gradually cooled at a temperature equal to or higher than the point A, the optical density becomes low due to the characteristic shown in FIG.

On the other hand, although not shown in FIG.
5 is composed of a control unit 101, a motor drive circuit 102, and a medium transport motor 103 as shown in FIG. 5, and a host device 100 such as a PC is connected to the control unit 101 and data to be printed by the rewrite printing apparatus is It is transmitted to the control unit 101. The control unit 101 controls the operation of the rewrite printing apparatus, and includes a microprocessor and the like. The control unit 101 is connected to a motor drive circuit 102 and has a medium detection sensor 104 and a non-contact temperature sensor 12
And the like, and the motor drive circuit 102 has a medium transport motor 10 for rotating and driving each transport roller.
3 are connected.

With the above control system, the motor is driven by the control of the control unit 101 based on the output signals of the medium detection sensor 104, the non-contact type temperature sensor 12, and the like, to convey the medium, and to perform the erasing and printing operations. .

The operation will be described below. FIG. 3 is a flowchart for performing print control of the rewrite printing apparatus according to the present embodiment. Hereinafter, the operation will be described with reference to the flowchart of FIG. First, in step S1, the medium transport motor 10
3 is turned on, each medium transport roller is driven, and the medium 11 is transported to the erasing head 2. By the time the medium 11 reaches the erasing head 2, the erasing head 2 is
Is turned on, the temperature is controlled by a thermistor in the erasing head so as to be equal to or higher than the point A in FIG. 2, and the erasing head is heated.
When the medium 11 comes near the erasing head, the erasing head 2 is brought into contact with the medium 11.

Then, in step S3, the erasing operation is performed until the entire medium 11 has passed the erasing head. Then, it is determined in step S3 whether the entire medium 11 has passed the erasing head. If it is determined that the entire medium 11 has not passed, the non-contact type temperature sensor 12 is determined in step S4.
When the temperature is equal to or higher than the point C in FIG. 2, the current applied to the erasing head 2 is suppressed in step S5 to lower the temperature, and the process returns to step S3.
If it is determined in step 4 that the medium surface temperature is not higher than the point C temperature, in step S6, if the medium surface temperature is lower than the point B temperature in FIG. 2, the applied current to the erase head 2 is increased in step S7. Then, the temperature is raised, and the process returns to step S3.

On the other hand, in step S6, when the temperature is equal to or higher than the point B temperature in FIG.
Since the optimum erasing temperature is lower than the point, the process returns to step S3 while keeping the erasing head current as it is, and the detection of medium passage and the temperature control of the erasing head after step S3 are performed.

When it is determined in step S3 that the medium 2 has passed through the erasing head 2 in step S3, the erasing head 2 is turned off in step S8. Is turned off, and the conveyance is stopped for a certain period of time in step S10 for slow cooling.
Is conveyed to the print head 3, the print head is turned on in step 12, and the printing process is performed in step 13,
In step 14, the print head is turned off, and in step 15, the medium is ejected.

Here, the printing process is an operation for printing with a general thermal head, and the temperature of the head at this time is shown in FIG.
The printing can be performed by printing as a point D or more. In other words, when heating the area of the medium to be erased as a surface to a constant temperature as in the case of erasing, it takes time to gradually cool down, but in the case of printing, heat is applied to the medium surface at only one point of the head, After the printing, it is rapidly cooled, and the characteristic becomes the characteristic of the point D in FIG. 2B, so that the optical density can be increased.

As described above, according to the rewritable printing apparatus of the present embodiment, at the time of erasing, the non-contact type temperature sensor provided at the subsequent stage of the erasing head detects the medium surface temperature in a non-contact manner and the erasing head. By performing the above temperature control, the temperature of the erasing head can be made more appropriate, so that the erasing characteristics can be improved.

Second Embodiment The rewrite printing apparatus according to the first embodiment requires an operation of stopping the medium during a slow cooling period with some margin by timer monitoring after erasing. It takes time until the next printing. Therefore, in order to solve the above-mentioned problem, the rewrite printing apparatus according to the second embodiment is provided with a non-contact type temperature sensor also near the print head 3, detects the medium surface temperature in a non-contact manner, and checks whether the medium is sufficiently cooled. By judging whether or not the printing operation can be started immediately.

FIG. 6 is a cross-sectional view showing the configuration of the rewrite printing apparatus according to this embodiment. Rewrite printer main body 1
Denotes an erasing head 2, a print head 3, a medium insertion guide 4, a medium conveyance path 5, each medium conveyance roller 6 to 10, a medium 11, a non-contact type temperature sensor a12 and a non-contact type temperature sensor b13.
Consists of

The erasing head 2 is an erasing head that controls the temperature of the erasing head by a thermistor (not shown) in the erasing head and erases the data printed on the medium 11 according to the erasing principle described later. Is a print head that controls the temperature of the print head by a thermistor (not shown) and prints on the medium 11 according to a printing principle described later. A non-contact type temperature sensor a12 is provided for the erase head 2 between the erase head 2 and the print head 3. A non-contact type temperature sensor b13 is provided near the print head 2 between the erase head 2 and the print head 3 and detects the surface temperature of the medium 11 without contact. This is a temperature sensor that detects the temperature without contact, and the medium insertion guide 4 inserts the medium 11 from an insertion port (not shown). A guide for inserting the medium to the medium conveying roller 6 before, media transportation path 5 medium insertion guide 4
The medium conveyance roller 6 is a conveyance roller that bites the medium 11 inserted by the medium insertion guide 4 and conveys the medium 11 along the medium conveyance path 5. The medium conveyance roller 8 is a conveyance roller for sucking the medium 11 conveyed by the medium conveyance roller 6, the medium conveyance roller 8 is a conveyance roller for conveying the medium near the erasing head by the erasing operation, and the medium conveyance roller 9 is a printing roller for the printing operation. The medium transport roller 10 is a transport roller that transports the medium near the head 3.
1 is a transport roller that discharges 1. These transport rollers are driven to rotate by a gear (not shown) by a motor of a control system described later, and transport the medium 11.

With the above configuration, the medium 11 is conveyed, erased, and printed under the control of the control system of the rewrite printing apparatus shown in FIG. 5, which is not shown in FIG. The configuration of the control system is the same as that of the control system of the rewritable printing apparatus according to the first embodiment, and a description thereof will be omitted. Further, the configuration and operation principle of the medium 11 used in the present invention are the same as those of the rewrite printing apparatus of the first embodiment, and therefore the description is omitted.

The operation will be described below. FIG. 7 is a flowchart for performing print control of the rewrite printing apparatus according to the present embodiment. Hereinafter, the operation will be described with reference to the flowchart of FIG. First, in step S21, the medium transport motor 1
03 is turned on, each medium transport roller is driven, and the medium 11 is transported to the erasing head 2. Then, before the medium 11 reaches the erasing head 2, the erasing head 2 is turned on in step S22, the temperature is controlled by a thermistor in the erasing head so that the temperature becomes higher than the point A in FIG. 2, and the erasing head is heated. When the medium 11 comes near the erasing head, the erasing head 2 is brought into contact with the medium 11.

Then, in step S23, the erasing operation is performed until the entire medium 11 has passed the erasing head. Then, it is determined in step S23 whether the entire medium 11 has passed through the erasing head. If it is determined that the entire medium 11 has not passed, the medium surface temperature is detected by the non-contact temperature sensor a12 in step S24. If the temperature is equal to or higher than the point C in FIG. 2, the applied current to the erase head 2 is suppressed in step S25 to lower the temperature, and the process returns to step S3.
If it is determined in step S24 that the medium surface temperature is not higher than the point C temperature, if the medium surface temperature is lower than the point B temperature in FIG. 2 in step S26, the current applied to the erase head 2 is reduced in step S27. The temperature is increased to increase the temperature, and the process returns to step S23.

On the other hand, if it is determined in step S26 that the temperature is equal to or higher than the point B in FIG. 2, that is, since the medium surface temperature is higher than the point B and lower than the point C, the optimum erase temperature is maintained. Then, the process returns to step S23 to detect the passage of the medium and control the temperature of the erasing head after step S23.

When it is determined that the medium 11 has been completely erased and the medium 2 has passed the erasing head 2 in step S23, the erasing head 2 is turned off in step S28, and the non-contact type temperature sensor is Medium 1 by b13
1 is detected to determine whether the medium surface temperature is below the point A in FIG. 2. If not, the medium transport motor is turned off in step S30 for slow cooling.
Return to step 30.

On the other hand, if the temperature is below the point A in step 29, it is determined that the medium 11 is gradually cooled, and in step 31, the medium transport motor 103 is turned on to turn on the medium 11.
Is conveyed to the print head 3, the print head is turned on in step 32, and the printing process is performed in step 33.
In step 34, the print head is turned off, and in step 35, the medium is ejected.

As described above, according to the rewrite printing apparatus of the present embodiment, at the time of erasing, the surface temperature of the medium is detected by the non-contact type temperature sensor provided near the rear stage of the erasing head, and In order to control the temperature, the temperature of the erasing head can be made more appropriate, and the medium surface temperature is detected in the vicinity of the print head by a non-contact type temperature sensor provided near the former stage of the print head. Since it can be more accurately determined whether or not the cooling has been performed, the erasing characteristics can be improved, and the time until printing after erasing can be shortened.

Third Embodiment In the rewrite printing apparatus according to the first embodiment and the second embodiment, since the medium 11 is gradually cooled by natural air cooling after erasing, it takes time. Therefore, in order to solve the above-mentioned problem, the rewrite printing apparatus according to the present embodiment is provided with a heat sink after the erasing head 2, and when the medium surface temperature falls below a certain temperature, the heat sink is brought into contact with the medium surface temperature. By forcibly slowing down the printing, it is possible to shift to the next printing operation in a short time.

FIG. 8 is a cross-sectional view showing the configuration of the rewrite printing apparatus according to this embodiment. Rewrite printer main body 1
Is composed of an erasing head 2, a print head 3, a medium insertion guide 4, a medium conveying path 5, respective medium conveying rollers 6 to 10, a medium 11, a non-contact type temperature sensor 12, and a heat sink 14.

The erasing head 2 is an erasing head for controlling the temperature of the erasing head by a thermistor (not shown) in the erasing head and erasing an image printed on the medium 11 according to an erasing principle described later. Is a print head that controls the temperature of the print head by a thermistor (not shown) and prints on the medium 11 in accordance with a printing principle described later. A non-contact type temperature sensor 12 is disposed downstream of the erase head 2 and has a surface temperature of the medium 11. The heat sink is disposed at the subsequent stage of the erasing head 2 to forcibly cool the medium after erasing, and the medium insertion guide 4 is provided with an insertion opening (not shown) for the medium 11. The medium transport path 5 is a guide for inserting the medium up to the position just before the medium transport roller 6. A transport path for sequentially conveying, medium medium conveying roller 6 is inserted by the medium insertion guide 4 1
1 is a conveyance roller that bites 1 and conveys it along the medium conveyance path 5, and the medium conveyance roller 7 is a conveyance roller that sucks the medium 11 conveyed by the medium conveyance roller 6,
The medium transport roller 8 is a transport roller that transports the medium near the erasing head by the erasing operation, the medium transport roller 9 is a transport roller that transports the medium near the print head 3 by the printing operation, and the medium transport roller 10 is not shown. A transport roller for discharging the medium 11 to the discharge port. These transport rollers are driven to rotate by a gear (not shown) by a motor of a control system described later, and transport the medium 11.

With the above configuration, the medium 11 is conveyed, erased, and printed based on the control of the control system of the rewrite printing apparatus shown in FIG. 5, which is not shown in FIG. The configuration of the control system is the same as the control system of the rewrite printing apparatus according to the first and second embodiments, and a description thereof will be omitted. Further, the configuration and operation principle of the medium 11 used in the present invention are the same as those of the rewrite printing apparatuses of the first and second embodiments, and thus the description is omitted.

The operation will be described below. FIG. 9 is a flowchart for performing print control of the rewrite printing apparatus of the present embodiment. Hereinafter, the operation will be described with reference to the flowchart of FIG. First, in step S41, the medium transport motor 1
03 is turned on, each medium transport roller is driven, and the medium 11 is transported to the erasing head 2. Then, before the medium 11 reaches the erasing head 2, the erasing head 2 is turned on in step S42, the temperature is controlled by a thermistor in the erasing head so that the temperature becomes higher than the point A in FIG. 2, and the erasing head is heated. When the medium 11 comes near the erasing head, the erasing head 2 is brought into contact with the medium 11.

In step S43, the erasing operation is performed until the entire medium 11 has passed the erasing head. Then, it is determined whether or not the entire medium 11 has passed through the erasing head in step S43. If it is determined that the entire medium 11 has not passed, the non-contact temperature sensor 12 detects the medium surface temperature in step S44. If the temperature is equal to or higher than the point C temperature in FIG. 2, the applied current to the erasing head 2 is suppressed in step S45 to lower the temperature, and the process returns to step S3. If it is determined that the medium surface temperature is equal to or lower than the point B temperature in FIG. 2 in step S46, the current applied to the erasing head 2 is increased in step S47 to increase the temperature.
Return to 43.

On the other hand, if it is determined in step S46 that the temperature is equal to or higher than the point B in FIG. 2, that is, since the medium surface temperature is higher than the point B and lower than the point C, the optimum erase temperature is maintained. Then, the process returns to step S43, and the detection of the passage of the medium and the temperature control of the erasing head from step S43 are performed.

When it is determined that the medium 2 has passed through the erasing head 2 in step S43, the erasing head 2 is turned off in step S48, and the non-contact type temperature sensor is The medium surface temperature is detected by 12 and if the medium surface temperature is not lower than the point D in FIG. 2, the medium transport motor 103 is turned off in step 50, and the temperature reaches the point E by natural air cooling. Stop transport until Then, when the medium surface temperature becomes equal to or lower than the point D in step 49, the medium transport motor 103 is turned on in step S51, and the heat sink 14 is brought into contact with the medium 11 in step 52 to forcibly cool the medium. While carrying the medium 11 to the print head 3, the print head is turned on in step 53, the printing process is performed in step 54, the print head is turned off in step 55, and the medium is discharged in step 56. I do. The reason why it is determined in step S49 whether the temperature is below the point D in FIG. 2 is that when the heat sink 14 is brought into contact with the medium 11 while the medium temperature is above the point D, the optical density increases,
This is because the medium is not erased cleanly.

As described above, according to the rewrite printing apparatus of the present embodiment, the medium surface temperature is measured by the non-contact type temperature sensor after erasing, and when the surface temperature becomes lower than a certain temperature, the heat sink is used. Since the cooling is performed slowly, the erasing operation can be performed at high speed.

Although the present invention has been described with reference to various embodiments, the present invention is not limited to these embodiments. For example, in the rewrite printing apparatus of the first embodiment, the The medium surface temperature is detected by a non-contact type temperature sensor disposed at the subsequent stage of the head 2 to control the temperature of the erasing head. After the medium 11 passes through the erasing head 2, the medium surface temperature is measured by the non-contact type temperature sensor. And the printing operation may be started when the medium surface temperature becomes equal to or lower than the point A temperature in FIG. Further, in the rewrite printing apparatus according to the second embodiment, the non-contact type temperature sensor is further disposed at the center, three or more, and more detailed temperature control is performed based on the temperature detection result of each non-contact type temperature sensor. It is also possible. For example, it is possible to control the temperature of the erasing head based on the average temperature of the outputs of the three non-contact type temperature sensors, or to control the temperature based on the maximum or minimum temperature. Then, only when the maximum temperature among the outputs of the three non-contact type temperature sensors becomes equal to or lower than the point A temperature in FIG. 2, the operation is shifted to the printing operation, so that the erasure can be surely performed.

The rewritable printing apparatus according to the first, second and third embodiments is composed of the erasing head 2 and the printing head 3, but the rewritable printing apparatus for erasing only is provided with only the erasing head 2. However, it goes without saying that the effects of the present invention described above can be obtained.

[0054]

As described above in detail, according to the present invention, by providing a non-contact type temperature sensor at the subsequent stage of the erasing head, the erasing head can be formed without generating an unerased portion due to the contact of the sensor. The temperature control can be performed optimally, and the process proceeds to the next printing operation by detecting the medium surface temperature as to whether or not the slow cooling has been performed, so that waste time for slow cooling can be eliminated. In addition, when the temperature of the medium after erasure becomes equal to or lower than a certain temperature, the cooling is forcibly performed by the heat sink, so that the printing operation can be started in a shorter time. In addition, since a conveyance path for slow cooling is not required, the apparatus can be downsized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a rewrite printing apparatus according to a first embodiment.

FIG. 2 is a diagram showing characteristics of a rewrite medium.

FIG. 3 is an operation flowchart of the rewrite printing apparatus according to the first embodiment;

FIG. 4 is a configuration diagram of a rewrite medium.

FIG. 5 is a block diagram illustrating a control system of the rewrite printing apparatus.

FIG. 6 is a cross-sectional view illustrating a configuration of a rewrite printing apparatus according to a second embodiment.

FIG. 7 is an operation flowchart of a rewrite printing apparatus according to a second embodiment.

FIG. 8 is a cross-sectional view illustrating a configuration of a rewrite printing apparatus according to a third embodiment.

FIG. 9 is an operation flowchart of a rewrite printing apparatus according to a third embodiment;

FIG. 10 is a cross-sectional view showing a configuration of a conventional rewrite printing apparatus.

FIG. 11 is an operation flowchart of a conventional rewrite printing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rewrite printing apparatus main body 2 Erase head 3 Print head 4 Medium insertion guide 5 Medium conveyance path 6, 7, 8, 9, 10 Medium conveyance roller 11 Medium 12, 13 Non-contact type temperature sensor 14 Heat sink

Claims (6)

[Claims] 1. A medium-type rewritable recording medium having a recording layer on a support surface, which exhibits a color developing property by being rapidly cooled after being heated at a first temperature, and having a fading property by being gradually cooled after being heated at a second temperature. Disposing a first non-contact temperature sensor at a stage subsequent to an erasing head in a rewritable printing apparatus that performs printing using a print medium as a print medium, and performing temperature control of the erasing head based on a temperature detected by the first non-contact temperature sensor. A rewrite printing apparatus characterized by the above-mentioned. 2. A printing operation is started when a medium surface temperature falls below the second temperature based on a temperature detected by the first non-contact type temperature sensor.
A rewrite printing apparatus as described in the above. 3. The erasing head according to claim 1, wherein a first non-contact temperature sensor is disposed near the erasing head, and the temperature of the erasing head is controlled based on a temperature detected by the first non-contact temperature sensor. 2. The rewrite printing apparatus according to 1. 4. The first non-contact type temperature sensor, wherein the first non-contact type temperature sensor is arranged near an erasing head, and a second non-contact type temperature sensor is arranged near a print head. 2. The printing apparatus according to claim 1, wherein the erasing head is controlled based on the detected temperature, and the printing operation is started when the temperature becomes equal to or lower than the second temperature based on the temperature detected by the second non-contact type temperature sensor. A rewrite printing apparatus as described in the above. 5. A heat sink is disposed at a stage subsequent to the erasing head, and when the temperature detected by the first non-contact type temperature sensor becomes equal to or lower than the first temperature, the heat sink is brought into contact with the print medium and gradually cooled. The rewriting printing apparatus according to claim 1, wherein the printing is performed. 6. The rewritable printing apparatus according to claim 1, wherein the erasing apparatus is dedicated to erasing.