JP2001162844A - Heat roller, and image-recording apparatus using the heat roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat roller whereby a consumed power at a standby time (preheat state), a temperature rise time period from the standby time to a use time, and power consumption are reduced, and a service life is improved. SOLUTION: A heat insulating layer 11 is formed on an outer circumferential face of a cylindrical roller base 10, and an electric resistor layer 12 as a heating layer is formed on an outer circumferential face of the heat insulating layer 11. Power feed electrodes 13a and 13b are set on the heat insulating layer 11 of both end parts of the roller base 10. The power feed electrodes 13a and 13b are respectively connected to the electric resistor layer 12. A protecting layer 14 is formed on an outer circumferential face of the electric resistor layer 12, and a heat storage elastic body 15 is formed on an outer circumferential face of the protecting layer 14. The heat insulating layer 11, the electric resistor layer 12 and the protecting layer 14 constitute a heating part. 16 and 17 are power feed terminals for feeding power to the power feed electrodes 13a and 13b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a card-like recording medium capable of recording and erasing an image by reversibly showing two states of color development and color erasure due to a difference in applied heat energy. A heat roller for erasing the existing image by heating, and erasing the existing image using the heat roller, and recording a new image using a thermal head on the recording medium from which the existing image has been erased. To an image recording apparatus.

[0002]

2. Description of the Related Art In recent years, cards using a recording material (thermal rewrite recording material) capable of repeating image recording and image erasing by heat for an image display section have been put to practical use. These have a configuration in which a magnetic recording unit and an image display unit capable of rewriting an image are provided on a thin PET sheet. The rewrite magnetic card having such a configuration is used, for example, as a point card in a retail business.

[0003] In addition to the magnetic cards described above, IC cards in which an IC chip is embedded and provided with a rewrite display section have been commercialized. Compared with a magnetic card that stores information in a magnetic recording unit, an IC card that stores information in a memory unit of an IC chip is more resistant to damage and forgery of stored information.

Therefore, an IC card having a large amount of stored information and excellent in tamper resistance, and a card provided with a rewrite display unit on a wireless card having a wireless communication function mounted on the IC card will be used in many fields in the future. Expected.

As a rewritable printer for recording or erasing images on these rewritable cards, for example, FIG.
There is a configuration shown in FIG. In FIG. 10, 100
Denotes a rewritable card having a rewrite display unit (not shown); 101, a hot stamp as image erasing means;
Reference numeral 02 denotes a thermal head which is an image recording unit. The hot stamp 101 has an area corresponding to the size of a rewrite display section, and an aluminum plate 104 is provided on the card side of a silicon rubber heater 103 in which a resistance heating element such as a nichrome wire is sandwiched between silicon rubbers containing glass fibers. It is configured by disposing a silicon rubber 105 and a base plate 106.

Reference numeral 107 denotes a pressing pad provided to face the hot stamp 101, and moves up and down in the direction of the arrow shown in the figure.
Press the rewrite card 100 against the hot stamp 101 and release it. Reference numeral 108 denotes a backup roller for holding the rewrite card 100 together with the thermal head 102.

[0007] The rewrite card 100 is conveyed in the direction of the arrow shown with the rewrite display section (not shown) facing upward, and when the hot stamp 101 is reached, the rewrite card 100 stops. Rewrite card 100 is hot stamp 10
Before the temperature reaches 1, the temperature of the hot stamp 101 is adjusted to a temperature that is sufficient for erasing the image on the rewrite display section.

The pressing pad 107 moves upward, and presses the rewritable display portion of the rewritable card 100 against the aluminum plate 104 of the hot stamp 101. By the heating of the hot stamp 101, the image written on the rewrite display section is erased. Next, the pressing pad 10
7 descends, rewrite card 100 and hot stamp 1
When the number 01 is separated, the rewrite card 100 is transported to the thermal head 102, and a new image is recorded on the rewrite card 100 by the thermal head 102.

The thermal rewritable recording material includes an organic low-molecular-weight / polymer matrix composite film material that changes to a cloudy / transparent state, and a leuco dye-based rewritable recording material that changes to a color-developed / decolorized state. The transparent state and the decolored state corresponding to the erased state occur in a specific temperature range. Therefore, in order to erase an image, it is desirable to heat the rewrite display section to a uniform temperature.

The hot stamp as the erasing means shown in FIG. 10 has excellent uniformity of temperature on the surface of the hot stamp because the aluminum plate in contact with the rewrite display portion has excellent thermal conductivity. When the rewritable card has a relatively flat surface, such as a magnetic card, the image can be erased well.

However, in the case of an IC card, as shown below, the surface of the card corresponding to the portion where the functional element is embedded is likely to have irregularities.

FIG. 11 shows the structure of a general wireless card. In FIG. 11, reference numeral 110 denotes an L embedded in the card.
The SI chip includes a CPU, a memory, wireless transmission / reception control means for recording and reading information in and out of the memory in a non-contact manner.
Reference numeral 111 denotes a transmitting / receiving antenna formed of a loop-shaped coil or the like buried in the periphery of the card.

Since the LSI chip 110 is buried in a space inside the card, a step around the LSI chip 110 is easily formed on the card surface. In the case where a rewrite display portion which is likely to have a step even in the peripheral portion of the antenna 111 is provided so as to avoid these portions, the unevenness of these surfaces does not hinder rewriting of an image by the rewrite printer. However, the entire surface of the card is not
In the case of, the erasing means shown in FIG. 10 causes the image to remain unerased in a portion corresponding to the peripheral portion of the LSI chip 110.

As an erasing means in a rewrite printer which solves such a problem, a heat roller for erasing shown in FIG. 12 is known. In FIG. 12, reference numeral 120 denotes a heat roller used for erasing an image. The heat roller 120 has a structure in which a resistor paste or a resistor 122 is provided as a heating element on a round bar-shaped roller base 121 made of ceramic or the like, and an elastic body 123 is provided thereon. In FIG. 12, those having the same reference numerals as in FIG. 11 are the same as those described in FIG.

When the heat roller having such a structure comes into contact with the rewrite display portion of the card, the surface of the heat roller becomes an elastic body. As a result, the problem of unerased images is reduced.

[0016]

However, in the conventional erasing means of the rewrite printer, in particular, like an IC card,
When the rewrite display unit includes a functional element buried part, there is a problem that an image remains unerased in a part corresponding to a peripheral part of the functional element.

Further, since the heating element is provided directly on the surface of the roller base material, heat is largely dissipated to the roller base material, which consumes a large amount of power, or rapidly rises from a preheated state to a required temperature. Is difficult to obtain.

Further, when a heating element is provided on the entire surface of the roller base material, the temperature distribution on the surface of the heat roller is high at the center and low at the ends, which makes it difficult to obtain a uniform surface temperature. .

Accordingly, the present invention relates to a heat roller and a heat roller in which power consumption during standby (preheated state), a temperature rise time from standby to use, power consumption is reduced, and life is improved. It is an object to provide an image recording apparatus using a roller.

Further, according to the present invention, a temperature distribution with a small temperature difference can be obtained over the entire surface of the heat roller, and even if the standby time is relatively long, abnormalities such as re-coloring or uneven color erasing can be prevented. It is an object of the present invention to provide a heat roller capable of erasing an unreliable image and an image recording apparatus using the heat roller.

Further, the present invention provides a heat roller capable of obtaining a stable temperature in a short time without excessive overshoot when the temperature is rapidly raised from a standby time to a predetermined erasing temperature, and an image using the heat roller. It is an object to provide a recording device.

[0022]

A heat roller according to the present invention comprises a roller base material having a circular side cross section, power supply electrodes provided at both ends of the roller base material, and A provided heat insulating layer, a heating element layer provided on the heat insulating layer and connected to each of the power supply electrodes, and a heat generating portion including a protective layer provided on the heating element layer; A heat storage elastic body that covers the heat generating portion.

In the heat roller according to the present invention, the heating element layer is divided into at least four or more in the circumferential direction of the roller base material, and each of the divided heating element layers is separated from the power supply electrode by a power supply electrode facing each other. And a space between each of the divided heating element layers is narrower in the end direction than in the axial center of the roller base material. .

In the heat roller of the present invention, the heating element layer is divided into a plurality in the axial direction of the roller base material, and the width of each of the divided heating element layers in the circumferential direction of the roller base material is reduced. The end portion of the roller substrate is wider than the center portion in the axial direction.

Further, the heat roller of the present invention comprises a roller base material having a circular side cross section, power supply electrodes provided at both ends of the roller base material, and a heat insulating member provided on the roller base material. A heating element layer provided on the heat insulation layer and connected to each of the power supply electrodes; an electrical insulation layer provided on the heating element layer; and an electrical insulation layer provided on the electrical insulation layer. The heat-generating unit includes a heat-generating portion made of a heat conductive film, and a heat storage elastic body that covers at least the heat-generating portion.

In the heat roller according to the present invention, the heating element layer is divided into at least four or more in the circumferential direction of the roller base material, and each of the divided heating element layers is separated from the feeding electrode by a feeding electrode facing each other. And a space between each of the divided heating element layers is narrower in the end direction than in the axial center of the roller base material. .

Further, the image recording apparatus of the present invention comprises a conveying means for conveying a card-shaped recording medium capable of repeatedly recording and erasing an image by a difference in applied heat energy, and a roller base material having a circular side section. A power supply electrode provided at each end of the roller base material, a heat insulating layer provided on the roller base material, and a heating element layer provided on the heat insulating layer and connected to each of the power supply electrodes. And a heat generating portion comprising a protective layer provided on the heat generating layer, and a heat storage elastic body covering at least the heat generating portion, and contacting the surface of the recording medium conveyed by the conveying means. By heating the recording medium, a heat roller for erasing an image already recorded on the recording medium, and a plurality of heating elements in pixel units for the recording medium on which the image has been erased by the heat roller. Selection And it includes a heat recording means for recording the new image by heating in units of pixels by driven.

Further, the image recording apparatus of the present invention comprises a conveying means for conveying a card-shaped recording medium capable of repeatedly recording and erasing an image by a difference in applied heat energy, and a roller base having a circular side section. A power supply electrode provided at each end of the roller base material, a heat insulating layer provided on the roller base material, and a heating element layer provided on the heat insulating layer and connected to each of the power supply electrodes. An electric insulating layer provided on the heating element layer, and a heat generating portion made of a heat conductive film provided on the electric insulating layer, and a heat storage elastic body covering at least the heat generating portion, By heating the recording medium by contacting the surface of the recording medium conveyed by the conveying means, a heat roller for erasing an already recorded image recorded on the recording medium, and an existing image is erased by the heat roller Before The recording medium, and a heat recording means for recording the new image by heating in units of pixels by selectively driving a plurality of heating elements in units of pixels.

According to the present invention, by providing a heat insulating layer between the roller base material and the heating element layer, the power consumption during standby (preheated state) and the power consumption during standby to use compared to the prior art. The heating time and power consumption are reduced, and the life is improved.

Further, according to the present invention, the heating element layer is divided in the circumferential direction and the axial direction of the roller base material, and the heating element layer and the heating element layer are separated so that there is no difference between the center temperature and the peripheral temperature. By regulating the relationship between the spaces, a temperature distribution with a small temperature difference over the entire heat roller surface is obtained, and
Even if the standby time is relatively long, it is possible to delete an image without any abnormality such as recoloring or uneven erasing.

Further, according to the present invention, a heat insulating layer is provided between the roller base material and the heating element layer, and a heat conductive film is provided between the heating element layer and the heat storage elastic body, thereby providing a standby state. When the temperature is rapidly raised from time to a predetermined erasing temperature, a stable temperature can be obtained in a short time without excessive overshoot.

[0032]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows a configuration of a rewrite printer as an image recording apparatus according to the present invention.
In FIG. 1, reference numeral 1 denotes a rewritable card (card-shaped recording medium) in which the entire surface (width 54 mm, length 84 mm) of the wireless card having the configuration shown in FIG. An erasing heat roller according to the present invention for erasing an image on an image display portion of the card 1 by heating;
Reference numeral 3 denotes a thermal head as a thermal recording means for recording an image on an image display section of the rewritable card 1, and 4 denotes a heat roller 2.
Temperature sensor as temperature detecting means for detecting the temperature of
Reference numeral 6 denotes a platen roller which is provided opposite to the heat roller 2 and also serves as a transfer unit. Reference numeral 6 denotes a platen roller which is provided opposite to the thermal head 3 and also serves as a transfer unit.

The recording material of the image display section of the rewritable card 1 is composed of an electron-donating color-forming compound and an electron-accepting compound. For example, there is an organic phosphoric acid having a long-chain aliphatic group, a carboxyl compound, or a combination of a phenol compound and a fluoran compound. This material exhibits a colored state by heating and melting, and becomes a decolored state by heating to a temperature lower than the coloring temperature. This change can occur reversibly.

Incidentally, such a recording material is, for example,
JP-A-5-96852 and JP-A-5-193257
No., etc.

Here, for example, the rewrite card 1
When transported at 0 mm / s, the image display section of the rewritable card 1 shows a saturated color density at an applied energy of about 0.4 mJ / dot or more when heated by the thermal head 3. The color is erased by heating at 70 to 75 ° C.

Next, the first heat roller 2 shown in FIG.
The embodiment will be described in detail with reference to FIG.

In FIG. 2, reference numeral 10 denotes a roller base material having a circular side section, in this example, a cylindrical shape. A heat insulating layer 11 is formed on the outer peripheral surface of the roller base material 10, and the outer peripheral surface of the heat insulating layer 11 is formed. Is formed with an electric resistor layer 12 as a heating element layer. Feeding electrodes 13a and 13b are provided on the heat insulating layers 11 at both ends of the roller base material 10, respectively. These feeding electrodes 13a and 13b are connected to the electric resistor layer 12, respectively. A protective layer 14 is formed on an outer peripheral surface of the electric resistor layer 12, and a thermal storage elastic body 15 is formed on an outer peripheral surface of the protective layer 14. Here, the heat insulating layer 11, the electric resistor layer 12, and the protective layer 14 constitute a heating section. In addition, 16 and 17 are power supply terminals for supplying power to the power supply electrodes 13a and 13b.

The roller base material 10 can be made of, for example, ceramic or metal. In this example, the outer diameter is 8 m.
m of ceramic was used. The heat insulating layer 11 can be made of a material having excellent heat insulating performance and having a smooth surface, for example, a thick film glaze material, a thin film silicon oxide, or a tantalum pentoxide material. Was used.

The electric resistor layer 12 generates a Joule heat when energized, and is made of a material having an excellent film-forming property, for example, ruthenium oxide as a thick film resistance material, tantalum nitride as a thin film material, tantalum / silicon oxide, or the like. In this example, a thick-film resistance film made of ruthenium oxide was used.

For the power supply electrodes 13a and 13b, a thick film or thin film conductive material, for example, a thick film material such as gold, silver or palladium, or a thin film material such as gold or aluminum can be used. In this example, palladium is used. Was used.

The protective layer 14 can be made of an electrically insulating thick film or thin film material, for example, a thick film material such as a glaze material, a thin film material such as silicon oxide or tantalum pentoxide material. Further, a heat-resistant plastic material, for example, polyimide or the like can be used. In this example, a thick glaze layer was used.

The heat storage elastic body 15 can be made of a rubber material having an appropriate hardness, for example, a silicone rubber or an NBR rubber having a hardness of 30 to 50 degrees. In this example, a silicone rubber having a hardness of 30 degrees is used. Was.

Next, a specific method of manufacturing the heat roller 2 according to the first embodiment configured as described above will be described. First, a thick-film glass paste is applied to almost the entire outer peripheral surface of a cylindrical roller base material 10 made of ceramic having an outer diameter of 8 mm and a length of 68 mm, and the thick-film glass paste is applied thereto by drying and firing. A glaze layer having a thickness of 40 μm is formed.

Next, on this heat insulating layer (glaze layer) 11, a thick sheet paste of ruthenium oxide having a high sheet resistance is applied by printing in a solid pattern having a width of 56 mm except for both end portions serving as power supply electrode portions. This is dried and fired to form the electric resistor layer 12.

Next, a palladium conductive paste is applied on both ends of the roller base material 10 by printing so that a part thereof overlaps with the electric resistor layer 12, and the paste is dried and fired to form the power supply electrode 1.
3a and 13b are formed.

Next, the electric resistor layer 1 excluding the power supply electrode portion
2, a thick-film glass paste is applied by printing, and dried and fired to form a glaze layer having a thickness of 150 μm, which becomes the protective layer 14.

Next, a silicon rubber tube having a thickness of 1 mm and a hardness of 30 degrees is covered on the protective layer (glaze layer) 14 to form a thermal storage elastic body 15.

The heat roller 2 was prepared as described above. The resistance value of the electric resistor layer 12 of the heat roller 2 was about 5Ω.

As a comparative example, a device without the heat insulating layer was prepared in the same process. In this case, the resistance value of the electric resistor layer of the heat roller was about 4.5Ω.

Next, a specific example in which the heat roller 2 thus configured is mounted on the rewrite printer shown in FIG. 1 will be described. As shown in FIG. 2, 24 V DC was supplied from the power supply terminal 16 that was in contact with one power supply electrode 13a of the rotating heat roller 2, and the power supply terminal 17 that was in contact with the other power supply electrode 13b was grounded. Further, a temperature sensor 4 having a thermocouple as a temperature detecting element is brought into contact with a part of the heat storage elastic body 15 as shown in FIG. Controls the power supply to the heat roller 2 to control the surface temperature of the heat roller 2.

The surface of the heat roller 2 when the image of the rewritable card 1 having the image display section having the erasing temperature range of 70 ° C. to 75 ° C., which is conveyed at a speed of 40 mm / s, is completely erased. The temperature was between about 200C and 220C. In the case of the heat roller of the comparative example, the surface temperature of the heat roller required for erasing was about 200 ° C. to 22 ° C.
It was 0 ° C.

Table 1 below shows a comparison between the average power consumption in the preheating state of 170 ° C., the time required to raise the temperature from the preheating state to 200 ° C. to 220 ° C., and the power consumption.

[0054]

[Table 1]

Further, after the preheating state for a certain period of time, erasing was performed, and the number of cards on which the image was completely erased was compared with the life of the heat roller 2, and a comparison was made. As a result, in the heat roller 2 of the first embodiment, 70,000 sheets and 50,000 sheets in the comparative example.

As is clear from the above Table 1 and the life comparison, the heat roller 2 according to the present invention having the heat insulating layer 11 is provided.
As compared with the related art, the power consumption in the standby state (preheated state), the heating time from the standby state to the use time, and the power consumption are reduced, and the life is improved.

As described above, it is important that the temperature of the surface of the heat roller is substantially the same regardless of the position and time of the surface among the specifications required for the heat roller.

Next, the second heat roller 2 shown in FIG.
The embodiment will be described in detail with reference to FIG.

FIG. 3 schematically shows a pattern of the electric resistor layer and the power supply electrode of the heat roller 2 according to the second embodiment developed on a plane, and other configurations are the same as those described above. Since it is the same as that of the first embodiment, illustration is omitted.

In FIG. 3, the electric resistor layer 12 has a width of 10 mm divided into a plurality in the circumferential direction of the roller base material 10.
Is provided as the divided resistance layer 20. In this example, 5
It shows a case where the image is divided into two. In this case, the width of the space between each divided resistance layer 20 differs depending on the position of the heat generating portion. That is, the width of the space 21 at the center of the heat generating portion is 2 mm, which is wider than the width (= 1 mm) of the space 22 located at the peripheral portion.

Each of the divided resistance layers 20 is
A plurality of extension electrodes 25 each extending from the power supply electrode 13a toward the power supply electrode 13b;
b to a plurality of extension electrodes 26 extending toward the power supply electrode 13a. In this case, the extension electrode 25 and the extension electrode 26 are disposed so as to be nested with each other.

Next, a specific method for manufacturing the heat roller 2 according to the second embodiment configured as described above will be described. In this example, the same material as that of the first embodiment was used for each part. Further, the manufacturing method is the same as that of the first embodiment described above, except that the printed patterns of the electric resistor layer and the power supply electrode are as shown in FIG. 3, and the detailed description will be repeated. Omitted. Electric resistance layer 1 of heat roller 2 in this case
The resistance value of No. 2 was about 8Ω.

Next, a specific example in which the heat roller 2 thus configured is mounted on the rewrite printer shown in FIG. 1 will be described. As shown in FIG. 2, 24 V DC was supplied from the power supply terminal 16 that was in contact with one power supply electrode 13a of the rotating heat roller 2, and the power supply terminal 17 that was in contact with the other power supply electrode 13b was grounded. Further, a temperature sensor 4 having a thermocouple as a temperature detecting element is brought into contact with a part of the heat storage elastic body 15 as shown in FIG. Controls the power supply to the heat roller 2 to control the surface temperature of the heat roller 2.

Also in the heat roller 2 according to the second embodiment, the temperature range in which the image on the image display section of the rewritable card 1 conveyed at a speed of 40 mm / s is satisfactorily erased is as follows:
About 200 ° C. to 220 ° C. as in the first embodiment described above.
Met.

In the heat roller of the comparative example manufactured in the first embodiment, when the preheating state is relatively long, even if the power supply control for temperature control is performed, as shown in FIG. In addition, a temperature distribution is generated in which the temperature decreases from near the axial center of the heat roller toward the peripheral portion. This temperature distribution is maintained even when the temperature is raised from the preheated state to the temperature for performing erasing, because the temperature rise is performed in a relatively short time.

As shown in FIG. 2, the temperature of the heat roller 2 in this rewrite printer is detected at the end of the heat generating portion. Therefore, when there is a temperature distribution as shown in FIG. 4A, the temperature at the end of the heat roller 2 is suitable for erasing an image, but the temperature at the center of the heat roller 2 is excessive and the entire surface is overheated. The color will recur over a long time.

FIG. 4B shows an axial temperature distribution in the heat roller 2 according to the second embodiment. The heat roller 2 according to the second embodiment divides a heat generating portion into a plurality of portions and provides a non-heat generating portion wider than a central portion where heat easily accumulates. Therefore, since the heat in the central portion is used to heat the heat storage elastic body on the non-heating portion, the temperature increase in the central portion is suppressed as compared with the comparative example, and the temperature difference with respect to the axial position is small. The distribution was obtained. When this heat roller 2 was used, even if the standby time was relatively long, the image could be erased without any abnormality such as recoloring or uneven erasure.

Next, the third roller of the heat roller 2 shown in FIG.
The embodiment will be described in detail with reference to FIG.

FIG. 5 schematically shows a pattern of the electric resistor layer and the power supply electrode of the heat roller 2 according to the third embodiment developed on a plane, and other configurations are the same as those described above. Since it is the same as that of the first embodiment, illustration is omitted.

In FIG. 5, the electric resistance layer 12 is provided as a divided resistance layer 30 divided into six in the axial direction of the roller base material 10. In this case, the width of the space between the divided resistance layers 30 differs depending on the position of the heat generating portion. That is, the width of the space 31 at the center of the heat generating portion is 0.5 mm, and the width of the space 34 at the portion connected to the power supply electrodes 13a and 13b is 0.2 mm. The width of each divided resistance layer 30 becomes wider toward it.

Next, a specific method of manufacturing the heat roller 2 according to the third embodiment configured as described above will be described. In this example, the same materials as in the first embodiment were used for the materials of the respective parts. The manufacturing method is the same as that of the first embodiment except that the printed patterns of the electric resistor layer and the power supply electrode are as shown in FIG. 5, and the detailed description is repeated. Omitted. In this case, the resistance value of the electric resistor layer 12 of the heat roller 2 was about 7Ω.

Next, a specific example in which the heat roller 2 thus configured is mounted on the rewrite printer shown in FIG. 1 will be described. As shown in FIG. 2, 24 V DC was supplied from the power supply terminal 16 that was in contact with one power supply electrode 13a of the rotating heat roller 2, and the power supply terminal 17 that was in contact with the other power supply electrode 13b was grounded. Further, a temperature sensor 4 having a thermocouple as a temperature detecting element is brought into contact with a part of the heat storage elastic body 15 as shown in FIG. Controls the power supply to the heat roller 2 to control the surface temperature of the heat roller 2.

Also in the heat roller 2 according to the third embodiment, the temperature range in which the image on the image display section of the rewritable card 1 conveyed at a speed of 40 mm / s is satisfactorily erased is:
About 200 ° C. to 220 ° C. as in the first embodiment described above.
Met.

FIG. 4C shows an axial temperature distribution in the heat roller 2 according to the third embodiment. The heat roller 2 according to the third embodiment divides the heat-generating portion into a plurality of portions, the width of the heat-generating portion is narrow at the central portion where heat easily accumulates, and the width of the heat-generating portion at the end portion where heat diffusion to the power supply electrode is large. Is provided, the temperature rise in the central portion is suppressed as compared with the comparative example, and a temperature distribution with a small temperature difference with respect to the axial position is obtained. When this heat roller 2 was used, even if the standby time was relatively long, the image could be erased without any abnormality such as recoloring or uneven erasure.

Next, the fourth roller of the heat roller 2 shown in FIG.
The embodiment will be described in detail with reference to FIG.
The same parts as those in FIG. 2 are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 6, reference numeral 10 denotes a cylindrical roller substrate, on which an insulating layer 11 is formed on an outer peripheral surface of the roller substrate 10, and an electric resistor layer 12 is formed on an outer peripheral surface of the insulating layer 11. Have been. Feeding electrodes 13a and 13b are provided on the heat insulating layers 11 at both ends of the roller base material 10, respectively. These feeding electrodes 13a and 13b are connected to the electric resistor layer 12, respectively. An electric insulating layer 41 is formed on an outer peripheral surface of the electric resistor layer 12, a heat conductive film 42 is formed on an outer peripheral surface of the electric insulating layer 41, and a heat storage elasticity is formed on an outer peripheral surface of the heat conductive film 42. A body 15 is formed. Here, the heat insulating layer 11, the electric resistor layer 12, the electric insulating layer 41, and the heat conductive film 42 constitute a heat generating portion. In addition, 16 and 17 are power supply terminals for supplying power to the power supply electrodes 13a and 13b.

The electric insulating layer 41 can be made of an electrically insulating thick film or thin film material, for example, a thick film material such as a glaze material, a thin film material such as silicon oxide or tantalum pentoxide material. Further, a heat-resistant plastic material, for example, polyimide or the like can be used. In this example, a thick glaze layer was used.

The heat conductive film 42 can be made of a metal foil such as aluminum or copper, and has a thickness of 30 μm in this example.
Was used.

Next, a specific method of manufacturing the heat roller 2 according to the fourth embodiment configured as described above will be described. First, a thick-film glass paste is applied to almost the entire outer peripheral surface of a cylindrical roller base material 10 made of ceramic having an outer diameter of 8 mm and a length of 68 mm, and the thick-film glass paste is applied thereto by drying and firing. A glaze layer having a thickness of 40 μm is formed.

Next, a high-sheet-resistance thick ruthenium oxide paste having a high sheet resistance is applied on the heat-insulating layer (glaze layer) 11 in a solid pattern having a width of 56 mm by printing, except for both end portions serving as power supply electrodes. This is dried and fired to form the electric resistor layer 12.

Next, a palladium conductive paste is applied to both ends of the roller base material 10 by printing so as to partially overlap the electric resistor layer 12, and the paste is dried and fired to form the power supply electrode 1.
3a and 13b are formed.

Next, the electric resistor layer 1 excluding the power supply electrode portion
2, a thick glass paste is applied by printing and dried and fired to form a glaze layer having a thickness of 30 μm, which becomes the electric insulating layer 41.

Next, the electric insulating layer (glaze layer) 41
Then, a copper foil having a thickness of 30 μm is bonded with a heat conductive adhesive to form a heat conductive layer. Next, a silicon rubber tube having a thickness of 1 mm and a hardness of 30 degrees is put on the heat conductive layer 42 to form the heat storage elastic body 15.

The heat roller 2 was prepared as described above. The resistance value of the electric resistor layer 12 of the heat roller 2 was about 5Ω.

As a comparative example, a device without the heat insulating layer was prepared in the same process. In this case, the resistance value of the electric resistor layer of the heat roller was about 4.5Ω.

Next, a specific example in which the heat roller 2 thus configured is mounted on the rewrite printer shown in FIG. 1 will be described. As shown in FIG. 6, 24 V DC was supplied from the power supply terminal 16 that was in contact with one power supply electrode 13a of the rotating heat roller 2, and the power supply terminal 17 that was in contact with the other power supply electrode 13b was grounded. Further, a temperature sensor 4 using a thermocouple as a temperature detecting element is brought into contact with a part of the heat storage elastic body 15 as shown in FIG. Controls the power supply to the heat roller 2 to control the surface temperature of the heat roller 2.

The surface of the heat roller 2 when the image of the rewritable card 1 having the image display section with the above-mentioned erasing temperature range of 70 ° C. to 75 ° C. conveyed at a speed of 40 mm / s is completely erased. The temperature was between about 200C and 220C. In the case of the heat roller of the comparative example, the surface temperature of the heat roller required for erasing was about 200 ° C. to 22 ° C.
It was 0 ° C.

Here, a comparison between the time from the start to the time when the temperature reaches an equilibrium state at 170 ° C., the average power consumption in the preheating state, and the time required to raise the temperature from the preheating state to 200 ° C. to 220 ° C. and the power consumption will be described. It is shown in Table 2 below.

[0089]

[Table 2]

After the preheating state for a certain period of time, erasing was performed, and the number of cards on which the image was completely erased was compared with the life of the heat roller 2. 70,000 sheets and 50,000 sheets in the comparative example.

FIG. 7 shows the temperature distribution in the axial direction of the heat roller 2 immediately after the temperature is raised from the preheated state to 200 ° C. to 220 ° C. FIG. 7A shows a fourth embodiment, and FIG. 7B shows a comparative example. In the heat roller 2 according to the fourth embodiment, the temperature of each part is 200 ° C. to 22 even immediately after the temperature rise.
Although the temperature is in the range of 0 ° C., in the heat roller of the comparative example, the temperature is in the range of 200 ° C. to 220 ° C. at the end where the temperature sensor is located, but the temperature overshoots in the center. This was realized by the heat of the heat generating portion being uniformly supplied to the heat storage elastic body 15 by the heat conductive layer 42 interposed between the electric insulating layer 41 and the heat storage elastic body 15.

As is evident from Table 2 above, the comparison of the service life and the comparison of the temperature distribution on the surface of the heat roller immediately after the temperature rise, the heat roller 2 according to the present invention provided with the heat insulating layer 11 and the heat conductive layer 42 is the same as the conventional one. In comparison, the power consumption during standby (preheating state), the temperature rise time from standby to use, and the power consumption have been reduced, and the life has been improved. Furthermore, temperature unevenness after the temperature rise is small, and stable temperature is maintained.

Next, the fifth heat roller 2 shown in FIG.
The embodiment will be described in detail with reference to FIG.

FIG. 8 schematically shows a configuration of the heat roller 2 according to the fifth embodiment. The heat roller 2 according to the fifth embodiment is similar to the heat roller 2 according to the fourth embodiment described above, except that the electric resistor layer 12 extends in the circumferential direction of the roller base material 10 in the same manner as in the second embodiment. It is divided into a plurality of portions and provided as a divided resistance layer 43, and the others are shown in FIG.
Since the configuration is the same as that of FIG. 6, the description is omitted.

That is, the method of setting the width of the space between the divided divided resistance layers 43, and the connection to the power supply electrodes 13a and 13b via the extension electrodes (not shown) of the divided divided resistance layers 43. The connection method is the same as in FIG. 3, and the other configuration is the same as in FIG.

Here, the time from the start in the fifth embodiment until the temperature reaches an equilibrium state at a temperature of 170 ° C.
Average power consumption in preheated state and 200
Table 3 below shows a comparison between the time required for raising the temperature from 0 ° C to 220 ° C and the power consumption.

[0097]

[Table 3]

After the preheating state for a certain period of time, erasing was performed, and the number of cards on which the image was completely erased was compared with the life of the heat roller 2. 70,000 sheets and 50,000 sheets in the comparative example.

FIG. 9 shows the temperature distribution in the axial direction of the heat roller 2 immediately after the temperature is raised from the preheated state to 200 ° C. to 220 ° C. FIG. 9A shows a fifth embodiment, and FIG. 9B shows a comparative example. In the heat roller 2 according to the fifth embodiment, the temperature of each part is 200 ° C. to 22 even immediately after the temperature rise.
Although the temperature is in the range of 0 ° C., in the heat roller of the comparative example, the temperature is in the range of 200 ° C. to 220 ° C. at the end where the temperature sensor is located, but the temperature overshoots in the center. This was realized by the heat of the heat generating portion being uniformly supplied to the heat storage elastic body 15 by the heat conductive layer 42 interposed between the electric insulating layer 41 and the heat storage elastic body 15.

As is clear from Table 3 above, the comparison of the life and the comparison of the temperature distribution on the surface of the heat roller immediately after the temperature rise, the heat roller 2 according to the present invention provided with the heat insulating layer 11 and the heat conductive layer 42 is the same as the conventional one. In comparison, the power consumption during standby (preheating state), the temperature rise time from standby to use, and the power consumption have been reduced, and the life has been improved. Further, the same operation and effect as in the second embodiment can be expected.

As described above, according to the above embodiment, in the heat roller, the heat insulating layer is provided between the electric resistance layer and the roller base material. In the state (2), the power consumption time, the temperature rise time from standby to use and the power consumption are reduced, and the life is improved.

Further, the electric resistance layer is divided in the circumferential direction and the axial direction of the roller base material, and the relationship between the divided resistance layer and the space is adjusted so that there is no difference between the center temperature and the peripheral temperature. By regulating the temperature, a temperature distribution with a small temperature difference over the entire surface of the heat roller can be obtained, and even if the standby time is relatively long, there is no abnormality such as recoloring or decoloring. Can be erased.

Further, a heat insulating layer is provided between the electric resistor layer and the roller base material, and a heat conductive film is provided between the heat generating portion and the heat storage elastic member, so that a predetermined erasing temperature can be obtained from the standby state. When the temperature is rapidly increased, a stable temperature can be obtained in a short time without excessive overshoot.

In the above-described embodiment, a wireless card having an image display unit capable of recording and erasing an image by reversibly showing two states of coloring and erasing by a difference in applied heat energy is described. In an image recording apparatus that records an image using a thermal head, a case has been described in which the present invention is applied to an erasing heat roller that erases an existing image recorded on a wireless card by heating. However, the present invention is not limited to this. However, the present invention can be similarly applied to a heat roller for heating other objects requiring heating. Particularly, the present invention exerts a remarkable effect when applied to a heat roller for heating a card-shaped object to be heated, which is likely to have irregularities on the surface.

[0105]

As described in detail above, according to the present invention, the power consumption during standby (preheating state), the temperature rise time from standby to use, and the power consumption are reduced, and the life is shortened. An improved heat roller and an image recording apparatus using the heat roller can be provided.

According to the present invention, a temperature distribution with a small temperature difference can be obtained over the entire surface of the heat roller, and
It is possible to provide a heat roller and an image recording apparatus using the heat roller, which enable erasure of an image without abnormality such as recoloring or uneven color erasing even when the standby time is relatively long.

Further, according to the present invention, when the temperature is rapidly raised from a standby time to a predetermined erasing temperature, a heat roller capable of obtaining a stable temperature without excessive overshoot in a short time and a heat roller using the same. Image recording apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram schematically showing a configuration of a rewrite printer as an image recording apparatus according to an embodiment of the present invention.

FIG. 2 is a vertical sectional side view showing a configuration of the heat roller according to the first embodiment of the present invention.

FIG. 3 is a diagram schematically showing an electric resistor layer and a power supply electrode pattern of a heat roller according to a second embodiment of the present invention developed on a plane.

FIG. 4 is a diagram for explaining a temperature distribution of a heat roller according to a second embodiment and a third embodiment in comparison with that of a comparative example.

FIG. 5 is a diagram schematically showing an electric resistor layer and a power supply electrode pattern of a heat roller according to a third embodiment of the present invention, which are developed on a plane.

FIG. 6 is a longitudinal sectional side view showing a configuration of a heat roller according to a fourth embodiment of the present invention.

FIG. 7 is a diagram for explaining the temperature stability of the heat roller according to the fourth embodiment when the temperature of the heat roller is raised, in comparison with that of a comparative example.

FIG. 8 is a vertical sectional side view showing a configuration of a heat roller according to a fifth embodiment of the present invention.

FIG. 9 is a diagram for explaining the temperature stability of the heat roller according to the fifth embodiment when the temperature of the heat roller is raised, in comparison with that of a comparative example.

FIG. 10 is a view for explaining a hot stamp which is an example of a conventional erasing unit.

FIG. 11 illustrates a structure of a wireless card in which a functional element is embedded.

FIG. 12 is a view for explaining a configuration of a conventional erasing heat roller.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rewrite card (card-shaped recording medium) 2 ... Heat roller (erasing means) 3 ... Thermal head (thermal recording means) 4 ... Temperature sensor (temperature detecting means) 5, 6 ... Platen roller (conveyance) Means 10 Roller base material 11 Heat insulation layer 12 Electric resistor layer (heating element layer) 13a, 13b Power supply electrode 14 Protective layer 15 Thermal storage elastic body 16 Power supply terminal 20, 30 , 43 ... divided resistance layer 21, 22, 31, 34 ... space 25, 26 ... extended electrode 41 ... electric insulating layer 42 ... thermally conductive film

Claims (12)

[Claims] 1. A roller base material having a circular side cross section, power supply electrodes provided at both ends of the roller base material, a heat insulating layer provided on the roller base material, and a heat insulating layer provided on the roller base material. A heating element layer provided on the heating element layer and connected to each of the power supply electrodes; a heating section including a protection layer provided on the heating element layer; and a heat storage elastic body covering at least the heating section. A heat roller characterized by: 2. The heating element layer is divided into at least four or more in the circumferential direction of the roller base material, and each of the divided heating element layers is extended from each of the power supply electrodes toward a power supply electrode facing each other. Wherein the space between the divided heating element layers is narrower in the end direction than in the axial center of the roller base material. 2. The heat roller according to 1. 3. The heating element layer is divided into a plurality of parts in the axial direction of the roller substrate, and the width of each of the divided heating element layers in the circumferential direction of the roller substrate is the roller substrate. 2. The heat roller according to claim 1, wherein an end direction is wider than an axial center portion of the heat roller. 4. A roller base material having a circular side cross section, power supply electrodes provided at both ends of the roller base material, a heat insulating layer provided on the roller base material, and a heat insulating layer provided on the roller base material. A heating element layer provided on the heating element layer and connected to each of the power supply electrodes; an electrical insulating layer provided on the heating element layer; and a heat conductive film provided on the electrical insulating layer. A heat roller, comprising: a heat generating portion; and a heat storage elastic body covering at least the heat generating portion. 5. The heating element layer is divided into at least four or more in the circumferential direction of the roller base material, and each of the divided heating element layers is extended from each of the power supply electrodes toward a power supply electrode facing each other. Wherein the space between the divided heating element layers is narrower in the end direction than in the axial center of the roller base material. 4. The heat roller according to item 4. 6. The heat roller according to claim 1, wherein the heat insulating layer is a glaze layer. 7. The heat roller according to claim 1, wherein the heating element layer is a thick film or a thin film resistor layer formed on the heat insulating layer. . 8. A conveying means for conveying a card-shaped recording medium capable of repeatedly recording and erasing an image according to a difference in applied heat energy, a roller base material having a circular side section, and both end portions of the roller base material. The power supply electrodes provided respectively, a heat insulating layer provided on the roller base material, a heating element layer provided on the heat insulating layer and connected to each of the power supply electrodes, and A heating section comprising a protective layer provided thereon, and a heat storage elastic body covering at least the heating section, and heating the recording medium by contacting the surface of the recording medium conveyed by the conveying means. A heat roller for erasing an image already recorded on the recording medium; and a plurality of heating elements selectively driven in pixel units for the recording medium on which the image has been erased by the heat roller. Image recording apparatus characterized by being equipped with a heat recording means for recording the new image by position of the heating. 9. The heating element layer is divided into at least four or more in the circumferential direction of the roller base material, and each of the divided heating element layers is extended from each of the power supply electrodes toward a power supply electrode facing each other. Wherein the space between the divided heating element layers is narrower in the end direction than in the axial center of the roller base material. 9. The image recording apparatus according to 8. 10. The heating element layer is divided into a plurality of heating element layers in the axial direction of the roller base material, and the width of each of the divided heating element layers in the circumferential direction of the roller base material is equal to the roller base material. 9. The image recording apparatus according to claim 8, wherein an end portion direction is wider than an axial center portion of the image recording device. 11. A conveying means for conveying a card-shaped recording medium capable of repeatedly recording and erasing an image according to a difference in applied heat energy, a roller base member having a circular side section, and both end portions of the roller base member. Power supply electrodes provided respectively, a heat insulating layer provided on the roller base material, a heating element layer provided on the heat insulating layer and connected to each of the power supply electrodes, on the heating element layer An electric insulating layer provided, a heat generating portion made of a heat conductive film provided on the electric insulating layer, and a heat storage elastic body covering at least the heat generating portion, and the recording conveyed by the conveying means. A heat roller that erases an image already recorded on the recording medium by heating the recording medium by contacting the surface of the medium; and a heat roller that erases the image already recorded by the heat roller. Departure The image recording apparatus characterized by equipped with thermal recording means for recording the new image by heating pixel, a by selectively driving the body in a pixel unit. 12. The heating element layer is divided into at least four or more in the circumferential direction of the roller base material, and each of the divided heating element layers is extended from each of the power supply electrodes toward a power supply electrode facing each other. Wherein the space between the divided heating element layers is narrower in the end direction than in the axial center of the roller base material. 12. The image recording device according to item 11.