JPH09226256A - Method for recording image and image recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a main image to be clearly observed and to make the erasing residual image to be scarcely observed by simultaneously erasing and recording the main image and a predetermined ground image of the background, and rewriting to record the main image and the ground image in the rewriting to record the image. SOLUTION: The CPU 1 of the image recorder synthesizes to generate pieces of image information generated from a main image information generator 2 and a ground image information generator 3, and sequentially stores them in an image memory 15. A thermal head drive controller 7 simultaneously records a character image and ground image in different image densities. In this case, it records the main image with first thermal energy and a predetermined ground image of the background for the main image with second thermal energy different from the first energy, and erases the part except the main image and the ground image with third energy different from the first and second energies to rewrite to record the main image and the ground image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording method and an image recording apparatus for rewriting and recording an image on a recording medium capable of reversibly developing and erasing color by heat.

[0002]

2. Description of the Related Art Recently, magnetic cards and IC cards having an information storage unit are used in a wide range of fields such as so-called telephone cards, prepaid cards, and personal identification cards (ID cards). However, with the spread of cards, problems such as counterfeiting, falsification, and unauthorized use of cards have occurred. In these recording media, the processing regarding the usage status is invisiblely processed by the recording medium processing device based on the stored information. Therefore, if there is a suspicion about the act of using the recording medium, the information must be displayed on the display device by the recording medium processing device, and it is not always possible for the user to fully understand the suspicion. It was

On the other hand, a display unit is provided on the recording medium so that the user of the recording medium can recognize the information on the usage state without going through the recording medium processing device, and a part of the stored information is recorded and displayed. Is being done. With this recording medium and system, the user can directly check the usage status,
Moreover, since the information can be confirmed by collating the stored information with the display information, it is possible to obtain higher reliability of the user.

Various proposals have been made for such a system (see, for example, Japanese Utility Model Laid-Open No. 1-174171 and Japanese Patent Laid-Open No. 3-212790). However, the recording medium is generally used repeatedly and a plurality of times, and it may not be possible to record and display sufficient information on the display unit a necessary number of times.

To solve such a problem, there is an idea of using a reversible recording material in the recording portion (for example, Japanese Patent Laid-Open No. Hei 3).
-116594, JP-A-3-218898, etc.). These are excellent in that images can be repeatedly recorded and erased. However, if the erasing conditions are severe,
The display image (recorded image) before rewriting may remain after rewriting. In addition, when a plurality of pieces of information are simultaneously displayed on the display unit, it is often inconvenient for the user. For example, the latest display is not always the one displayed at the bottom, and in order to know this, it is necessary to compare the display contents.

In order to make it difficult to see the remaining image,
There has been proposed a printing paper provided with a pattern for camouflaging print marks that have been previously erased on a printing paper to be printed with an ink using a coloring agent that decolorizes under a predetermined condition, for example, infrared light irradiation as a decoloring condition. (For example, the actual Kaihei 6
-17963).

Further, a non-color-change image composed of at least one or more reversible thermo-color-change images that reversibly change color by heat and a combination of a large number of fine lines having a visual density higher than that of a support supporting the image is overprinted. A thermochromic printed matter is proposed (for example, see Japanese Utility Model Laid-Open No. 6-59059).

[0008]

SUMMARY OF THE INVENTION
According to the techniques disclosed in Japanese Patent Publication No. 7963 and Japanese Utility Model Laid-Open No. 6-59059, the visual interference due to the unerased printed image that can be reversibly recorded and erased is reduced.

However, in both techniques, a pattern for camouflaging print marks must be printed in advance, so that the area where a reversible image is printed is limited. Alternatively, it is necessary to prepare various print media provided with a pattern having a high effect of reducing print marks according to the characteristics of the reversible image. Further, since the pattern is fixed, it is easy to make a counterfeit product having the same pattern, and there is a problem that the security of the recording medium cannot be maintained.

A background tint block image is printed in advance on a main image on a display unit of a recording medium, which is a conventional technique,
In the method of recording a main image (also referred to as a main image) on it, the tint block image is printed with a constant density. On the other hand, in the image recording apparatus, there are variations in the thermal head and the thermal head drive control section, or variations in the sensitivity of the material of the recording medium display section. As a result, a density difference occurs between the main image recorded by the image recording apparatus and the tint block image printed in advance. When there is a density difference between the main image, the tint block image, and the unprinted image, there is a difference in the performance of suppressing visual interference due to the unprinted image of the tint block image, and the effect may not be sufficiently exerted.

In addition, there is no proposal of a recorded image which can be easily distinguished from the alteration of the reversible image which is relatively easy to rewrite as compared with the irreversible image. Therefore, the present invention makes it possible to make the main image clearly visible and make the unerased image difficult to see even when the erasure conditions are strict or the background density cannot be erased. It is an object of the present invention to provide an image recording method and an image recording device that can obtain a desired effect.

The present invention is also directed to an image recording method and an image recording method which can always exert the effect of a tint block image on a main image even if there are differences in image recording apparatuses or variations in erasing sensitivity and recording sensitivity of recording media. The purpose is to provide a device.

[0013]

The image recording method of the present invention is an image recording method in which an image is rewritten and recorded on a recording medium capable of reversibly developing and erasing color by heat. It is characterized in that the main image and the tint block image are rewritten and recorded by simultaneously erasing and recording a predetermined background tint block image on the main image.

Further, the image recording method of the present invention is an image recording method of rewriting and recording an image on a recording medium capable of reversibly developing and erasing color by heat.
Of heat energy, and a predetermined tint block image serving as a background for the main image is recorded with second heat energy different from the first heat energy, and the main image and the tint block image are excluded. The portion as the first and second
It is characterized in that the main image and the tint block image are rewritten and recorded by erasing with the third thermal energy different from the thermal energy of.

The image recording apparatus of the present invention is an image recording apparatus for rewriting and recording an image on a recording medium capable of reversibly developing and erasing color by heat, and generates main image information to be recorded. Main image information generating means, a tint block image information generating means for generating tint block image information serving as a background for the main image information to be recorded, main image information generated by the main image information generating means and the tint block pattern. Recorded image information generating means for combining the tint block image information generated by the image information generating means to generate image information to be recorded on the recording medium, and the recorded image information generated by this recorded image information generating means is image information. Determining means for determining whether it is non-image information, heating time determining means for determining a heating time for forming one image point of an image according to the determination result of this determining means, and the heating time determining means It is heating control according to the heating time, and a thermal recording means for recording and erasing of images simultaneously on the recording medium.

The image recording apparatus of the present invention is an image recording apparatus for rewriting and recording an image on a recording medium capable of reversibly developing and erasing colors by heat, and generates main image information to be recorded. The main image information generating means, the temperature detecting means for detecting the environmental temperature, and the background pattern image information to be recorded with respect to the main image information to be recorded having the density corresponding to the environmental temperature detected by the temperature detecting means. The copy-forgery-inhibited pattern image information generating means, the copy-forgery-inhibited pattern image information generated by this copy-forgery-inhibited pattern image information generating means, and the main image information generated by the main image information generating means are combined, and image information to be recorded on the recording medium Recording image information generating means for generating, determination means for determining whether the recording image information generated by the recording image information generating means is image information or non-image information, and one image of an image according to the determination result of this determining means. Heating time determining means for determining the heating time for forming the recording medium, and thermal recording in which heating is controlled according to the heating time generated by the heating time determining means, and the image is erased and recorded on the recording medium at the same time. And means.

Further, the image recording apparatus of the present invention can record and erase the main image and the tint block image by showing two states of coloring and erasing depending on the difference in heating energy, and
An image recording apparatus for rewriting and recording a main image and a tint block image on a recording medium having a storage section for storing information on the recorded main image, wherein the main image stored in the storage section of the recording medium. Reading means for reading information concerning the main image, a first judging means for judging whether or not the tint block image is rewritten based on the information concerning the main image read by the reading means, and a main means for generating main image information to be recorded. When the image information generating means and the first determining means determine that the tint block image is to be rewritten, the tint block image information generating means for generating the tint block image information serving as a background for the main image information to be recorded, and the main tint image information generating means. A recorded image information generating means for synthesizing the main image information generated by the image information generating means and the tint block image information generated by the tint block image information generating means to generate the image information to be recorded on the recording medium. And a second judging means for judging whether the recorded image information generated by the recorded image information generating means is image information or non-image information, and one image point of the image according to the judgment result of the second judging means. Heating time determining means for determining the heating time for forming the recording medium, and thermal recording in which heating is controlled according to the heating time generated by the heating time determining means, and the image is erased and recorded on the recording medium at the same time. And a writing means for writing information about the main image recorded by the thermal recording means in the storage section of the recording medium.

According to the present invention, the main image and the copy-forgery-inhibited pattern image serving as the background of the main image are simultaneously overwritten and recorded, so that the main image and the copy-forgery-inhibited pattern image can be rewritten in one step. Further, even if the erasing conditions are strict or the background density cannot be erased, the main image can be seen clearly and the unerased image can be made invisible. Further, since the margin of the rewriting condition is extremely small, the rewriting recording can be performed on the reversible recording material which cannot be used conventionally.

Further, by controlling the density of the copy-forgery-inhibited pattern image according to the environmental temperature, it is possible to realize both the sharpness of the rewritten main image and the invisibleness of the unerased image even when the environmental temperature changes.

Even if the image recording apparatus is different or the erasing sensitivity and recording sensitivity of the recording medium are varied, the main image and the tint block image are overwritten at the same time so that the tint block image and the main image can be recorded. Since there is no difference in density, the effect of the tint block pattern on the main image can always be exhibited.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First, a first embodiment will be described. FIG. 1 shows the configuration of an image recording apparatus according to the first embodiment. In FIG. 1, a CPU (Central Processing Unit) 1 that controls the entire apparatus includes a main image information generating unit 2 that generates a character image that is a main image recorded on a recording medium P described later, and a recording medium P. The tint block image generation unit 3 that generates a tint block image that becomes a background with respect to the main image with the tint block pattern recorded in 1., the recorded image information generation unit 4 that generates image information to be recorded on the recording medium P, and the generated recorded image information. According to the heating time of the thermal head for forming one image point of the image, that is, the energization time generation unit 5, which determines the energization time to the thermal head,
The thermal head drive control unit 7 that drives and controls the thermal head 6 as a thermal recording unit, and the transport control unit 9 that drives and controls the motor 8 connected to the transport roller (not shown) that transports the recording medium P are the bus 10. Are respectively connected via.

The main image information generating section 2 converts a character generator 11 for generating a character image as bitmap pattern information, and dots forming a character image called from the character generator 11 into dot information having density information. It is composed of a multi-value density conversion unit 12.

The copy-forgery-inhibited pattern image information generation unit 3 has a multi-valued density image memory 13 for storing a plurality of types of copy-forgery-inhibited pattern (copy-forgery-inhibited pattern image) having predetermined density information. A desired tint block pattern is selectively generated from the number 13.

The recorded image information generation unit 4 includes a main image information generated from the main image information generation unit 2 and a tint block image information generation unit 3.
And a tint block image information generated from the print information, and generates a print information to be recorded on the recording medium P. A record information combining unit 14 and an image memory 15 that stores the generated record image information.
It is composed of

The energization time generation unit 5 includes a mark / space determination unit 16 for determining whether the recorded image information generated by the recorded image information generation unit 4 is image information (mark) or non-image information (space), and a mark. / Consists of an energization time control unit 17 that determines the energization time to the thermal head 6 according to the determination result of the space determination unit 16 and the like.

For example, as shown in FIG. 2, the recording medium P reversibly records a visible image on one surface of a support 21 formed of polyethylene terephthalate or a synthetic resin such as polyvinyl chloride. An erasable display portion (recording layer) 22 and a protective layer 23 are sequentially laminated.

The recording material of the display section 22 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. Such recording materials are described, for example, in Japanese Patent Application Laid-Open Nos. 5-96852 and 5-193257.

FIG. 3 shows characteristics when the display section 22 of the recording medium P shown in FIG. 2 is colored and erased by the thermal head. The black circle line a shows the color development characteristic, the white circle line b shows the decolorization characteristic, and the broken line c shows the background density. As shown in FIG. 3, the recording medium P cannot be erased to the background density even under the maximum erase condition. This means that a print mark remains even when the recorded image is erased.
Further, generally, due to a difference in a recording state depending on a device, a print mark often remains on a recording medium capable of reversibly recording and erasing an image. As described below, the present invention is characterized in that even if such print marks remain, they are difficult to see.

The recording material of the display section 22 is not limited to the above-mentioned recording materials, but can be reversibly converted into both transparent and cloudy states depending on the temperature applied to the recording material (for example,
For example, refer to JP-A-55-154198. This reversible recording material is capable of reversibly coloring and erasing, and can reversibly convert both transparent and cloudy states at a given temperature. For example, in a transparent state, when the temperature is raised from room temperature to a clouding temperature or higher in a transparent state, the recording material changes from a transparent state to a cloudy state, and maintains the cloudy state even when the temperature returns to room temperature. Then, when the temperature of the recording material is raised from room temperature to the transparent temperature range and returned to room temperature, the cloudy state is changed to the transparent state, and the transparent state is maintained as it is.

Next, the rewriting operation of the image recording apparatus according to the first embodiment having the above-mentioned structure will be described with reference to the flow chart shown in FIG. The recording medium P is loaded into the loading section (not shown) of this apparatus,
When the character string and the tint block pattern (tint pattern image) to be recorded on the recording medium P are selected and designated from the control panel (not shown) (S1), the CPU 1 is designated from the image memory 13 of the tint block image information generating unit 3. The tint block pattern is read (S2). This tint block pattern is represented as density information, and here, density information that gives a density of 0.7 is given.

Similarly, the CPU 1 reads out a designated character image from the character generator 11 of the main image information generator 2 (S3). Although the bit information of the read character image is binary, it is converted by the multi-value density conversion unit 12 into bit information having density information such that the density becomes 1.5 so that the density becomes higher than the tint block density. (S4).

According to the position recorded on the display unit 22 of the recording medium P, the character image information and the copy-forgery-inhibited pattern image information recorded at the same position are called by the record information combining unit 14 of the record image information generating unit 4. When the two pieces of information are present at the same position, the recording information synthesizing unit 14 gives priority to the character image information and generates the image information to be recorded on the display unit 22 of the recording medium P (S5). The generated recording image information is sequentially stored in the image memory 15 of the recording image information generating unit 4 (S6).

Here, the operation of the recording information synthesizer 14 will be described in detail with reference to FIGS. 5 to 7 schematically show the information state of each address of the image information. FIG. 5 shows an example of the character information "T", in which black circles represent recorded bit information and white circles represent unrecorded bit information. FIG. 6 shows an example of a tint block pattern. Black triangles represent recorded bit information, and white circles represent unrecorded bit information. In the figure, a to j indicate columns and 1 to 10 indicate rows. Hereinafter, it is assumed that (column, row) represents an address on the memory.

The tint block pattern information is sequentially read out in synchronization with the sequential reading of the character image information from the address (a, 1) to (a, 2), (a, 3), .... Then, the recording information synthesizing unit 14 synthesizes the bit information of the same address of the character image information and the tint block pattern information. In this case, if both are non-recording bits, they are combined as non-recording bits (white circles), and the others are recorded bits (black circles and black triangles), and are stored in the image memory 15 according to the result. The state of the image memory 15 is shown in FIG.

The recorded image information is sequentially supplied from the image memory 15 for storing the recorded image information to the mark / space determination section 16 of the energization time generation section 5. The mark / space determination unit 16 determines whether the recorded image information is image information (mark) or non-image information (space) (S7).

The energization time control unit 17 is provided with an energization time table (not shown) corresponding to the image information (mark) and the non-image information (space), and the energization time is determined using this energization time table. Yes (S8). That is, when the recorded image information is the non-image information (space), the energization time is not given to the apparatus that only performs recording, but the non-image information (space) is also given the energization time in the present example in which rewriting is performed. The energization time for the non-image information is the time corresponding to the driving energy of the thermal head which is the maximum erasing condition shown in FIG. In this example, for example, 0.77 ms corresponding to a driving energy of 0.33 mJ / dot.
Was hit.

The energization time table of the image information (mark) shows the number of bits representing the image density and the energization time from the relationship between the density and the driving energy shown in FIG. Relationship is given. The image information is given the energization time according to the number of bits representing the given density. In this example, for example, the energization time of 1.51 ms for obtaining the character density of 1.5 in the character information,
In the tint block image, a tint block density of 0.7 is obtained and the energization time is 1.0
9 ms is applied to each.

Here, the relationship among the print mark density, the tint block density, and the main image density is important. In rewriting recording when printing marks remain, it is important that the rewritten main image can be clearly read and the remaining printing marks are difficult to see. Therefore, in this example, the background pattern density is set between the print mark density and the main image density to solve the above-mentioned problems. That is, in the above-described embodiment, the print trace density is 0.52, the tint block density is 0.7, and the main image density is 1.5. When the tint block density is higher than the main image density, the sharpness of the main image is lost. Further, when the tint block density is equal to or lower than the print mark density, the print mark cannot be suppressed.

The energization time information thus determined is supplied to the thermal head drive controller 7. The thermal head drive control unit 7 selectively causes the heating elements of the thermal head 6 corresponding to the recording position to generate heat at different temperatures based on the supplied energization time information, so that the character image and the tint block image are simultaneously and different images. The density is recorded (S9). In this example, the heating is performed so that the recorded image is erased even in the portion other than the recorded image portion. As a result, the existing image that has already been recorded is erased at the same time as the recording of a new image, and the rewriting and recording of the image can be performed without going through the two steps of erasing and recording.

As described above, the heating energy of the thermal head 6 corresponding to the image information (coloring) is selectively colored, and the heating energy corresponding to the background information (colorless) is selectively decolorized. A recording method in which recording and erasing are performed at the same time is called an overwrite recording method. The details of this recording method are described in, for example, Japanese Patent Laid-Open No. 4-197647, so refer to it.

Next, the effect of simultaneously recording a main character image and a tint block image will be described. FIG.
FIG. 1 schematically shows a state in which the image recording apparatus of FIG. 1 rewrites and records the recorded image information which has been subjected to the above processing. According to the above-described recording method, for example, a state in which the character “A” is rewritten and recorded with the character “T” and the tint block pattern is shown in FIG.
In FIG. 9B, the letter “T” is shown in black and the tint block pattern is shown in white circles. FIG. 8A shows a state in which the character “A” is simply rewritten and recorded with the character “T”. In the rewrite recording (FIG. 8a) by the conventional recording method, the old image “A” that has disappeared can be recognized as a part of the character, which hinders the visibility of the character “T” and makes it difficult to read the character “T”. Become. On the other hand, in the image recorded by the recording method of the present example, the remaining image “A” is also made a part of the background pattern by the background pattern, and the visibility of the new image “T” is not hindered. .

By thus recording the main image and the tint block image at the same time, the tint block image and the main image can be recorded even if there is a difference in image recording apparatus or variations in the erasing sensitivity and recording sensitivity of the display section of the recording medium. Since a constant density difference is maintained between and, the effect of the copy-forgery-inhibited pattern image with respect to the main image can always be exhibited.

When rewriting and recording an image on a recording medium capable of reversibly developing and erasing colors by heat, the main image and the tint block image are simultaneously erased and recorded to rewrite the main image and the tint block image. By recording, even if a print mark is generated by rewriting, the main image is recorded clearly and the print mark can be made invisible.

Next, a second embodiment will be described. FIG. 9 shows the configuration of the image recording apparatus according to the second embodiment. The difference between the second embodiment and the first embodiment is that a temperature sensor 18 as a temperature detecting means for detecting an environmental temperature is provided, and the copy-forgery-inhibited pattern image information generating section 3 is provided with a plurality of copy-forgery-inhibited pattern patterns Image), a tint block image memory 19 and a tint block image memory 1
The multi-value density conversion unit 20 converts dots forming the tint block pattern read from the No. 9 into dot information having predetermined density information. The other parts are the same, and therefore the same reference numerals are given and description will be given. Omit it.

The erasability of the rewritable recording material used in the above-described first embodiment or the reversible recording material having the cloudiness / transparency change described above is affected by the ambient temperature. In particular, in a low temperature environment, the maximum erasing density becomes high and the erasing characteristics deteriorate. FIG. 10 shows an example of changes in erasing characteristics due to differences in environmental temperature of the recording medium shown in FIG. The curve d represents the erasing characteristic (erasing 1) in a normal temperature environment, and the curve e represents the erasing characteristic (erasing 2) at 0 ° C.
The straight line f indicates the background density, respectively. As shown in the figure, it can be seen that the print mark density varies depending on the environmental temperature even when rewriting is performed depending on the maximum erasing condition. In the case of this example, the maximum erasing concentration in a normal temperature environment is 0.52,
It is 0.7 in a ° C environment.

When rewrite recording is performed while the tint block density is kept constant regardless of the environmental temperature, for example, when the tint block density is set to 0.7 as in the first embodiment, the rewritten main image of the rewritable main image is obtained. The sharpness and the invisibleness of the erased print mark can be realized by rewriting recording, but in the environment of 0 ° C., the density of the tint block and the density of the print mark are the same, so that the print mark is easy to read. The second embodiment is characterized in that both the sharpness of the rewritten main image and the difficulty of seeing the print marks are realized even when the environmental temperature changes.

The rewriting operation of the image recording apparatus according to the second embodiment will be described below with reference to the flowchart shown in FIG. When the recording medium P is loaded into a loading unit (not shown) of the apparatus and a character string and a tint block pattern (tint pattern image) which are main images to be recorded on the recording medium P are selected and designated from a control panel (not shown) (S11). , C
PU1 is a tint block image memory 19 of the tint block image information generation unit 3.
The copy-forgery-inhibited pattern specified from is read out (S12).

The temperature sensor 18 detects the environmental temperature of the apparatus (S13), and the detected temperature information (0 ° C.) is C
Input to PU1. The CPU 1 is assigned a density according to the detected temperature information based on the relationship between the preset environmental temperature (0 ° C.) and the tint block density, and the multi-value density conversion unit 20 operates according to the density information. The read tint block pattern information is provided with temperature information that is 0.8, which is higher than the print mark density of 0.7 at an environmental temperature of 0 ° C. (S14).

Similarly, the CPU 1 reads out the designated character image from the character generator 11 of the main image information generating section 2 (S15). Although the bit information of the read character image is binary, it is converted by the multi-value density conversion unit 12 into bit information having density information such that the density becomes 1.5 so that the density becomes higher than the tint block density. (S16).

According to the position recorded on the display unit 22 of the recording medium P, the character image information and the copy-forgery-inhibited pattern image information recorded at the same position are called by the record information combining unit 14 of the record image information generating unit 4. The recording information synthesizing unit 14 gives priority to the character image information when both pieces of information exist at the same position, and generates image information to be recorded on the display unit 22 of the recording medium P (S17). The generated recorded image information is sequentially stored in the image memory 15 of the recorded image information generation unit 4 (S18). Note that the operation of the recording information synthesizing unit 14 is the same as that of the above-described first embodiment, and therefore its explanation is omitted.

The recorded image information is sequentially supplied from the image memory 15 for storing the recorded image information to the mark / space determination section 16 of the energization time generation section 5. The mark / space determination unit 16 determines whether the recorded image information is image information (mark) or non-image information (space) (S19).

The energization time control section 17 is provided with an energization time table (not shown) corresponding to the image information (mark) and the non-image information (space), and the energization time is determined using this energization time table. Yes (S20). That is, when the recorded image information is non-image information (space),
An apparatus for performing only recording does not give the energizing time, but in this example of rewriting, the energizing time is also given to the non-image information (space). The energization time for the non-image information is the time corresponding to the driving energy of the thermal head which is the maximum erasing condition shown in FIG. In this example, for example,
1.12 corresponding to a driving energy of 0.48 mJ / dot
ms was applied.

The energization time table of the image information (marks) is based on the relationship between the density and the driving energy in the 0 ° C. environment. Has been given a relationship with. The image information is given the energization time according to the number of bits representing the given density. In this example, for example, the energization time of 1.86 ms for obtaining the character density of 1.5 is applied to the character information, and the energization time of 1.4 ms for obtaining the tint block density of 0.8 is applied to the tint block image, respectively.

The energization time information thus determined is supplied to the thermal head drive controller 7. The thermal head drive control unit 7 selectively causes the heating elements of the thermal head 6 corresponding to the recording position to generate heat at different temperatures based on the supplied energization time information, so that the character image and the tint block image are simultaneously and different images. The density is recorded (S21).

As described above, by controlling the density of the tint block image in accordance with the environmental temperature, the rewritten main image can be clearly recorded and the erased print marks are difficult to see regardless of the change in the environmental temperature. it can.

Next, a third embodiment will be described. FIG. 12 shows the configuration of the image recording apparatus according to the third embodiment. The difference between the third embodiment and the first embodiment is that the tint block rewriting determination unit 2 that determines the rewriting of the tint block image according to preset conditions.
5, a magnetic head 26 that reads information about the main image from the magnetic recording portion of the recording medium P, a read magnetic head controller 27 that controls the magnetic head 26, and a magnetic head that writes information about the main image to the magnetic recording portion of the recording medium P. 28, and a write magnetic head control unit 29 for controlling the magnetic head 28 is added. The other parts are the same, and therefore, the same reference numerals are given and description thereof is omitted.

FIG. 13 shows an example of the recording medium P used in this embodiment. That is, the recording medium P is
On one surface of the support 21 formed of polyethylene terephthalate or a synthetic resin such as polyvinyl chloride,
A display unit (recording layer) 22 capable of reversibly recording and erasing a visible image and a protective layer 23 are sequentially laminated, and a magnetic recording unit 24 as an information storage unit is provided on the other surface. ing. Except for the magnetic recording section 24, the configuration and material are the same as those of the recording medium P in the above-described first embodiment, so description thereof will be omitted.

This recording medium P is used as a prepaid card, for example, and is rewritten and recorded on the display unit 22 every time the balance is updated. Further, in the magnetic recording unit 24, information about balance information which is a main image is recorded.

The rewriting operation of the image recording apparatus according to the third embodiment will be described below with reference to the flow chart shown in FIG. When the recording medium P is loaded into the loading unit (not shown) of this apparatus, the read magnetic head control unit 27 and the magnetic head 26 read the balance information, which is the main image, from the magnetic recording unit 24 of the recording medium P ( S3
1) is sent to the CPU 1. The CPU 1 calculates the latest balance from the read balance information and the amount of money consumed by the current use, and sends the calculation result to the tint block rewriting determination unit 25.

The copy-forgery-inhibited pattern rewriting determination unit 25 determines whether the calculated latest balance is a preset copy-forgery-inhibited pattern rewriting condition, for example, the balance is 1000 yen or less (S32). When the latest balance is determined to be 1000 yen or less, the CPU 1 selects a tint block pattern different from the number corresponding to the latest balance and the preset current tint block pattern (S33).

Next, the CPU 1 causes the copy-forgery-inhibited pattern image information generation unit 3
The selected and designated tint block pattern is read from the tint block image memory 19 (S34). This tint block pattern is represented as density information, and here, density information that gives a density of 0.7 is given.

Similarly, the CPU 1 reads out the selected and designated character image from the character generator 11 of the main image information generator 2 (S35). Although the bit information of the read character image is binary, the multi-value density conversion unit 12 sets the density to 1. so that the density becomes higher than the tint block density.
It is converted into bit information having density information of 5 (S3
6).

According to the position recorded on the display unit 22 of the recording medium P, the character image information and the copy-forgery-inhibited pattern image information recorded at the same position are called by the record information combining unit 14 of the record image information generating unit 4. The recording information synthesizing unit 14 gives priority to the character image information when both pieces of information exist at the same position, and generates image information to be recorded on the display unit 22 of the recording medium P (S37). The generated recording image information is sequentially stored in the image memory 15 of the recording image information generating unit 4 (S38). Note that the operation of the recording information synthesizing unit 14 is the same as that of the above-described first embodiment, and therefore its explanation is omitted.

The recorded image information is sequentially supplied from the image memory 15 for storing the recorded image information to the mark / space determination section 16 of the energization time generation section 5. The mark / space determination unit 16 determines whether the recorded image information is image information (mark) or non-image information (space) (S39).

The energization time control unit 17 is provided with an energization time table (not shown) corresponding to image information (mark) and non-image information (space), and the energization time is determined using this energization time table. Yes (S40). That is, when the recorded image information is non-image information (space),
An apparatus for performing only recording does not give the energizing time, but in this example of rewriting, the energizing time is also given to the non-image information (space). The energization time for the non-image information is the time corresponding to the driving energy of the thermal head which is the maximum erasing condition shown in FIG. In this example, for example, 0.77 m corresponding to a driving energy of 0.33 mJ / dot.
s was applied.

The energization time table of the image information (mark) shows the number of bits representing the image density and the energization time based on the relationship between the density and the driving energy shown in FIG. Relationship is given. The image information is given the energization time according to the number of bits representing the given density. In this example, for example, the energization time of 1.51 ms for obtaining the character density of 1.5 in the character information,
In the tint block image, a tint block density of 0.7 is obtained and the energization time is 1.0
9 ms is applied to each.

Here, the relationship among the print mark density, the tint block density, and the main image density is important. In rewriting recording when printing marks remain, it is important that the rewritten main image can be clearly read and the remaining printing marks are difficult to see. Therefore, in this example, the background pattern density is set between the print mark density and the main image density to solve the above-mentioned problems. That is, in the above-described embodiment, the print trace density is 0.52, the tint block density is 0.7, and the main image density is 1.5. When the tint block density is higher than the main image density, the sharpness of the main image is lost. Further, when the tint block density is equal to or lower than the print mark density, the print mark cannot be suppressed.

The energization time information thus determined is supplied to the thermal head drive controller 7. The thermal head drive control unit 7 selectively causes the heating elements of the thermal head 6 corresponding to the recording position to generate heat at different temperatures based on the supplied energization time information, so that the character image and the tint block image are simultaneously and different images. The density is recorded (S41).
In this example, even for parts other than the recorded image part,
Heating is performed to erase the recorded image.
As a result, the existing image that has already been recorded is erased at the same time as the recording of a new image, and the rewriting and recording of the image can be performed without going through the two steps of erasing and recording.

Next, the CPU 1 operates the write magnetic head controller 29 and the magnetic head 28 to
The calculated latest balance information is used as the magnetic recording unit 24 of the recording medium P.
And the balance information is updated (S42).

In step S32, the latest balance is 10
When it is determined that the amount is 00 yen or more, the CPU 1 rewrites only the updated balance information on the display unit 22 of the recording medium P by overwrite recording according to the above procedure.

Thus, the magnetic recording portion 24 of the recording medium P is
The balance information, which is the main image read from, is compared with preset conditions to determine the rewriting of the tint block image. Only when the conditions are satisfied, rewriting of the main image and tint block image is performed by overwrite recording. Is.

[0072]

As described above in detail, according to the image recording method and the image recording apparatus of the present invention, the main image and the tint block image are simultaneously overwritten for overwriting, thereby rewriting and recording the main image and the tint block image in one step. Can be done.
Further, even if the erasing conditions are strict or the background density cannot be erased, the main image can be seen clearly and the unerased image can be made invisible. Further, since the margin of the rewriting condition is extremely small, the rewriting recording can be performed on the reversible recording material which cannot be used conventionally.

By controlling the density of the copy-forgery-inhibited pattern image in accordance with the environmental temperature, it is possible to realize both the sharpness of the rewritten main image and the invisibleness of the unerased image even when the environmental temperature changes.

Even if the image recording apparatus is different, or the erasing sensitivity and recording sensitivity of the recording medium vary, the main image and the tint block image are overwritten at the same time so that the tint block image and the main tint image are recorded. Since there is no difference in density, the effect of the tint block pattern on the main image can always be exhibited.

[Brief description of drawings]

FIG. 1 is a block diagram schematically showing a configuration of an image recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view schematically illustrating a configuration of a recording medium.

FIG. 3 is a diagram showing recording and erasing characteristics of a recording medium.

FIG. 4 is a flowchart illustrating a rewriting / recording operation of image information.

FIG. 5 is an explanatory diagram for combining recorded image information from main image information and tint block pattern information.

FIG. 6 is an explanatory diagram for combining recorded image information from main image information and tint block pattern information.

FIG. 7 is an explanatory diagram for combining recorded image information from main image information and tint block pattern information.

FIG. 8 is a diagram for explaining the effect of simultaneously rewriting the main image and the tint block pattern.

FIG. 9 is a block diagram schematically showing a configuration of an image recording apparatus according to a second embodiment of the present invention.

FIG. 10 is a diagram showing an example of a difference in erasing characteristic due to a difference in environmental temperature of a recording medium.

FIG. 11 is a flowchart illustrating a rewriting / recording operation of image information.

FIG. 12 is a block diagram schematically showing the configuration of an image recording device according to a third embodiment of the invention.

FIG. 13 is a sectional view schematically showing the configuration of a recording medium.

FIG. 14 is a flowchart illustrating a rewriting / recording operation of image information.

[Explanation of symbols]

P ... recording medium, 1 ... CPU, 2 ... main image information generating section, 3 ... tint block image information generating section, 4 ... recorded image information generating section, 5 ... energizing time generating section (heating time determining means) ), 6
...... Thermal head (heat recording means), 7 ...... Thermal head drive controller, 11 ...... Character generator, 1
2 ... Multi-value density conversion unit, 13 ... Multi-value density image memory,
14 ... Record information composition section, 15 ... Image memory, 16 ...
... Mark / space determination unit, 17 ... Energization time control unit,
18 ... Temperature sensor (temperature detecting means), 19 ... Background pattern image memory, 20 ... Multi-value density conversion section, 21 ... Support,
22 ... Display unit (recording layer), 24 ... Magnetic recording unit (storage unit), 25 ... Copy-forgery-inhibited pattern rewriting determination unit (determination unit), 26
...... Magnetic head (reading means), 27 ...... Reading magnetic head control unit, 28 ...... Magnetic head (writing means), 29 ......
Write magnetic head controller.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location G06K 17/00 B41M 5/18 101A (72) Inventor Shinichi Ito 70 Yanagicho, Kawasaki-shi, Kanagawa Prefecture Toshiba Corporation Yanagimachi factory

Claims (7)

[Claims] 1. An image recording method for rewriting and recording an image on a recording medium capable of reversibly developing and erasing color by heat, which comprises a main image and a predetermined tint block image as a background for the main image. An image recording method characterized in that the main image and the tint block image are rewritten and recorded by simultaneously erasing and recording. 2. An image recording method for rewriting and recording an image on a recording medium capable of reversibly developing and erasing color by heat, wherein the main image is recorded with a first heat energy and the main image is recorded. In contrast, a predetermined background pattern image serving as a background is recorded with second thermal energy different from the first thermal energy, and a portion excluding the main image and the background pattern image is the first and second thermal energy. An image recording method characterized by performing rewriting recording of a main image and a tint block image by erasing with a third thermal energy different from. 3. The image recording method according to claim 2, wherein the first to third heat energies have a relationship of first heat energies> second heat energies> third heat energies. . 4. An image recording apparatus for rewriting and recording an image on a recording medium capable of reversibly developing and erasing colors by heat, comprising main image information generating means for generating main image information to be recorded. Background pattern image information generating means for generating a background pattern image information for the main image information to be recorded, main image information generated by the main image information generating means and the background pattern image information generating means. Recorded image information generating means for synthesizing the tint block image information and generating image information to be recorded on the recording medium, and determining whether the recorded image information generated by the recorded image information generating means is image information or non-image information. According to the determination means, the heating time determination means for determining the heating time for forming one image point of the image according to the determination result of the determination means, and the heating time generated from the heating time determination means. An image recording apparatus comprising: a thermal recording unit which is controlled to heat and simultaneously erases and records an image on the recording medium. 5. An image recording apparatus for rewriting and recording an image on a recording medium capable of reversibly developing and erasing color by heat, comprising main image information generating means for generating main image information to be recorded. A temperature detecting means for detecting an environmental temperature; and a tint block image information generating means for generating a tint block image information as a background for the main image information to be recorded having a density corresponding to the ambient temperature detected by the temperature detecting means. A recorded image information generation unit that combines the tint block image information generated by the tint block image information generation unit and the main image information generated by the main image information generation unit to generate image information to be recorded on the recording medium; Determining means for determining whether the recorded image information generated by the recorded image information generating means is image information or non-image information, and a heating time for forming one image point of an image according to the determination result of the determining means A heating time determining means for determining the temperature of the recording medium, and a thermal recording means for controlling the heating in accordance with the heating time generated by the heating time determining means to simultaneously erase and record an image on the recording medium. An image recording device characterized by. 6. The copy-forgery-inhibited pattern image information generating means stores the copy-forgery-inhibited pattern image storage means for storing the copy-forgery-inhibited pattern image, and sets the copy-forgery-inhibited pattern image stored in this copy-forgery-inhibited pattern image storage means to the environmental temperature detected by the temperature detecting means. The image recording apparatus according to claim 5, further comprising density conversion means for converting the tint block image information having a corresponding density. 7. A main image and a tint block image are recorded by showing two states of coloring and erasing depending on the difference in heating energy.
What is claimed is: 1. An image recording apparatus that rewrites and records a main image and a tint block image onto a recording medium that is erasable and that has a storage unit that stores information about a recorded main image. Read-out means for reading out the information about the main image stored in, and a first judging means for judging whether or not the tint block image is rewritten based on the information about the main image read by the reading means; When the main image information generating unit that generates main image information and the first determination unit determine to rewrite the tint block image, the tint block image that generates the tint block image information that becomes the background for the main image information to be recorded. The information generating means, the main image information generated by the main image information generating means and the tint block image information generated by the tint block image information generating means are combined to generate image information to be recorded on the recording medium. The recording image information generating means, the second determining means for determining whether the recording image information generated by the recording image information generating means is image information or non-image information, and the determination result of the second determining means. Heating time determining means for determining a heating time for forming one image point of an image, and heating control is performed according to the heating time generated by the heating time determining means to erase and record the image on the recording medium. An image recording apparatus comprising: a thermal recording unit that simultaneously performs the above and a writing unit that writes information about a main image recorded by the thermal recording unit into a storage unit of the recording medium.