JP2002370455A - Heat sensitive recording medium and thermal printer using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To record a favorable color image even without employing an ink ribbon. SOLUTION: This heat sensitive recording medium is made of a base material 2 made of a transparent sheet, on one side of which a red color developing layer 3 developing color with a low heat energy EL is laminated, while on the other side of the base material a black color developing layer 4 developing color with a high heat energy EH is laminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal recording medium used in a thermal printer and a thermal printer using the recording medium.

[0002]

2. Description of the Related Art First, an example of a thermal printer capable of performing double-sided printing will be described with reference to FIG. As shown in the drawing, a paper feed unit 51 is disposed below the thermal printer 50 in the figure, and the paper feed unit 51 has a box-shaped supply capable of storing a plurality of recording papers 52 of, for example, A4 size. The paper tray 53 is provided with a paper placing plate 54 at the right bottom in the drawing, the front of which can be turned up and down on the right side of the drawing with a support portion as a fulcrum 54a.

A part of the recording paper 52 near the front end is placed on the paper placing plate 54. Further, an elastic member (not shown) is disposed below the sheet placing plate 54 on the right side in the drawing, which is closer to the front, and the elastic member acts to push the sheet placing plate 54 upward as indicated by an arrow D. The urging force is applied. A paper feed roller 55 rotatable in a direction indicated by an arrow F which is a counterclockwise direction is provided above the paper loading plate 54 near the front end. The support portion is provided at the fulcrum 5 on the paper feed roller 55.
The upward rotation of the paper placing plate 54 at 4a causes the uppermost recording paper 52 of the recording paper 52 placed on the paper placing plate 54 to come into elastic contact with the front end portion. I have.

[0006] The recording paper 52 stored in such a paper supply section 51 is separated from the recording paper 52 by rotating a paper supply roller 55 in the direction of arrow F so that the uppermost recording paper 52 is separated. And is transported downstream in the transport direction E. Further, the paper transport direction E
A plate-like guide plate 56 for guiding the fed recording paper 52 to a first recording unit 57 and a second recording unit 62, which will be described later, is provided downstream of the recording medium. This guide plate 5
6 is formed to be curved as shown in FIG. 1, and is arranged on the downstream side of the guide plate 56 so as to change the direction of the recording paper 52 sent from the paper feeding unit 51 upward in the drawing at a substantially right angle. The first recording means 57 guides the user. The first recording means 57 can print a desired image on one surface of the recording paper 52, for example, on the front side.

The first recording means 57 is provided with a first platen 58 having a flat surface made of rubber or the like on the right side of the recording sheet 52 turned upward by a guide plate 56 shown in FIG. Has been established. Below the first platen 58, a first recording means 57 as a paper transport mechanism,
A paper feed roller 59 and a first pressure roller 60 that can be pressed against the first paper feed roller 59 with a predetermined pressure and that can rotate following the rotation of the first paper feed roller 59 are provided. . Then, by rotating the first paper feed roller 59,
Between the first paper feed roller 59 and the first pressure roller 60,
The recording paper 52 conveyed from the paper supply unit 51 can be conveyed in the direction of the first platen 58.

A first thermal head 61 is provided on the side opposite to the first platen 58, and the first thermal head 61 can freely contact and separate from the first platen 58 by a head driving mechanism (not shown). . The first thermal head 61 has a plurality of dot-shaped heating elements (not shown), and selectively heats the heating elements based on the recording information to record ink on an ink ribbon described later. Thermal transfer to one surface of the paper 52 or recording paper 52
When a heat-sensitive recording paper is used, the heat-sensitive layer is directly colored to record a desired image.

A second recording means 62 capable of recording a desired image on the other side of the recording paper 52 is provided downstream of the first recording means 57 shown in FIG. . The second recording means 62 has the same basic configuration as that of the first recording means 57, and only the components are arranged on opposite sides, so that detailed description will be omitted.

[0008] Further, below the second platen 63 in the figure, the first recording means 62 serves as a paper transport mechanism for the first recording means.
The second roller formed slightly larger than the diameter of the paper feed roller 59
A paper feed roller 64 and a second pressure roller 65 that can be pressed against the second paper feed roller 64 and that can rotate following the rotation of the second paper feed roller 64 are provided. The second paper feed roller 64 is controlled so that the rotation speed is the same as that of the first paper feed roller 59.

The recording paper 52 conveyed from the first recording means 57 is pressed and held between the second paper feeding roller 64 and the second pressing roller 65, and the second paper feeding roller 6 is pressed.
4, the recording paper 52 is moved by the transport mechanism of the second recording means 62 to the second position on the downstream side in the transport direction E.
The sheet is transported between the thermal head 65 and the second platen 63. The second paper feed roller 64
The holding force for holding the recording paper 52 while pressing and holding the recording paper 52 between the first paper feed roller 59 and the first pressing roller 60 is larger than the holding force between the first paper feed roller 59 and the first pressing roller 60. .

Next, the recording operation of the thermal printer 50 capable of performing such double-sided recording will be described with reference to FIG.

First, the uppermost recording sheet 52 among the plurality of recording sheets 52 stored in the sheet supply section 51 is separated and conveyed by rotating the sheet supply roller 55 in the direction of arrow F. The recording paper 52 conveyed from the paper supply unit 51 is guided by a guide plate 56 and is conveyed to a first recording unit 57 located downstream of the guide plate 56 in the conveyance direction. Then, when the leading end of the conveyed recording paper 52 comes into contact with the pressure contact portion between the first paper feed roller 59 and the pressure roller, the first paper feed roller 59 is driven to rotate, and the recording paper 52 is moved to the first position.
The first platen 5, which is pressed and held between the paper feed roller 59 and the pressure roller and located downstream of the first paper feed roller 59.
8 and the first thermal head 61 in the head-up state.

The amount of rotation of the first paper feed roller 59 is controlled by a recording control unit (not shown) so that one surface of the recording paper 52 is positioned at the recording start position, and the rotation of the first paper feed roller 59 is controlled. To stop. Next, the first thermal head 61 is moved down, and the first thermal head 6 is moved through the recording paper 52 and an ink ribbon (not shown).
1 is pressed against the first platen 58, and while the ink ribbon is being conveyed, the heating element of the first thermal head 61 is selectively heated based on the recording information to record a desired image on one surface of the recording paper 52. I do. In addition, as the recording paper 52,
When using thermal paper, ink ribbon is not required,
Recording can be performed by directly coloring the thermal paper.

The recording paper 52 being recorded by the first recording means 57 is conveyed to the second recording means 62 by the first paper feed roller 59. Then, the leading end of the recording paper 52 being recorded on one surface by the first recording means 57 is pressed and held between the second paper feed roller 64 and the second pressing roller 65, and
The rotation of the paper feed roller 64 causes the recording paper 52 to be transported between the second platen 63 and the second thermal head 66 in the head-up state.

Next, the second thermal head 66 is pressed against the second platen 63 via the recording paper 52 and the ink ribbon, and the heating elements of the second thermal head 66 are selectively heated according to the recording information to perform recording. By recording a desired image on the other side of the sheet 52, a desired image can be recorded on both sides of the recording sheet 52.

Here, the diameter of the second paper feed roller 64 is
Since the diameter of the first paper feed roller 59 is larger than the diameter of the first paper feed roller 59, the recording paper 52
Is larger than the conveyance amount of the recording paper 52 by the conveyance mechanism of the first recording means 57. For this reason, the recording paper 52 that is being recorded on both sides by the first recording unit 57 and the second recording unit 62 always has the second recording unit 62.
Tension is generated by the transport mechanism of the first embodiment, and the slack of the recording paper 52 between the first recording unit 57 and the second recording unit 62 can be prevented.

[0016]

However, in the conventional thermal printer 50 as described above, when a color image is recorded using an ink ribbon, it is necessary to select an ink ribbon for each color. However, there is a problem in that the ink ribbon becomes complicated or the amount of dust increases because the used ink ribbon must be discarded. Alternatively, when a thermal paper is used as the recording paper 52 without using the ink ribbon, there is a problem that a color image cannot be recorded.

The present invention solves the above-mentioned problems, and provides a recording medium capable of recording a color image without using an ink ribbon, and a thermal printer capable of efficiently performing color recording using the recording medium. The purpose is to do.

[0018]

In order to achieve the above object, the present invention provides a recording medium capable of recording a color image without using an ink ribbon, and a color recording method using the recording medium. An object of the present invention is to provide a thermal printer that can be efficiently operated.

In order to achieve the above object, the heat-sensitive recording medium according to the present invention is characterized in that a color-forming layer that develops a different color is provided on both sides of a substrate made of a transparent sheet.

According to the heat-sensitive recording medium of the present invention, one color is developed by applying heat energy to the color developing layer of one color provided on one surface of the substrate, and the other surface of the substrate is developed. By applying heat energy to the provided coloring layer of another color, the coloring of the other color can be performed. Also,
The heat-sensitive recording medium can be visually recognized through one surface from the other surface.

Further, another thermosensitive recording medium of the present invention comprises a yellow coloring layer which forms a color at a predetermined temperature and a cyan coloring layer which forms a color at a lower temperature than the yellow coloring layer, on one surface of a substrate made of a transparent sheet. And, on the other surface of the substrate, the yellow coloring layer and a magenta coloring layer that develops a color at a lower temperature than the yellow coloring layer.

According to the heat-sensitive recording medium of the present invention, it is possible to record yellow and cyan on one surface of the heat-sensitive recording medium, and to record yellow and magenta on the other surface. Can be.

Further, another heat-sensitive recording medium of the present invention comprises, on one surface of a substrate made of a transparent sheet, a yellow coloring layer which develops a color at a predetermined temperature, and a cyan coloring layer which develops a temperature lower than the yellow coloring layer. And, on the other surface of the base material, a black coloring layer that forms color at substantially the same temperature as the yellow coloring layer, and a magenta coloring layer that forms color at substantially the same temperature as the cyan coloring layer. It is characterized by.

According to another heat-sensitive recording medium of the present invention, it is possible to record yellow and cyan on one surface of the heat-sensitive recording medium, and to record black and magenta on the other surface. be able to.

Further, another thermosensitive recording medium of the present invention has a yellow coloring layer which forms a color at a predetermined temperature between two transparent sheets, and the yellow coloring layer is formed on each of the two sheets on the surface of a substrate. A cyan coloring layer and a magenta coloring layer which form a color at a lower temperature than the layer.

According to another heat-sensitive recording medium of the present invention, the color-forming layers of each color can be separated by each base material.

Further, another thermosensitive recording medium of the present invention is such that a yellow coloring layer which develops a color with a predetermined heat energy is laminated on one surface of a base material made of a transparent sheet, and on the surface of the yellow coloring layer, Laminating a film made of a transparent sheet, and on the surface of the film, laminating a cyan coloring layer that develops with lower thermal energy than the yellow coloring layer, and on the other surface of the base material, the yellow coloring layer A black coloring layer that develops with substantially the same heat energy is laminated, a film made of a transparent sheet is laminated on the surface of the black coloring layer, and a color is formed on the surface of the film with a lower thermal energy than the black coloring layer. Magenta coloring layers are laminated.

According to another heat-sensitive recording medium of the present invention, it is possible to perform recording in yellow and cyan on one surface of the heat-sensitive recording medium, and to perform recording in black and magenta on the other surface. be able to. Further, the coloring layers of each color can be separated by each substrate.

Further, in the thermal printer according to the present invention, a first thermal head for printing on the front surface of the conveyed recording medium, a second thermal head for printing on the back surface, and the first thermal head. A first platen against which the thermal head presses through the recording medium, a second platen against which the second thermal head presses through the recording medium, and a paper transport mechanism for transporting the recording medium; The first thermal head and the second thermal head are provided with at least a first heating temperature and a second heating temperature higher than the first heating temperature, and the first to fifth means are used as the recording medium. The first and second thermal heads are first driven at the first heat-generating temperature to perform recording, and thereafter the first thermal recording medium is used.
And controlling the second thermal head to be driven at the second heat generation temperature.

According to the thermal printer of the present invention, according to the thermal recording medium of the first means of the present invention, the thermal energy is applied to the coloring layer of one color provided on one surface of the substrate by applying thermal energy. By developing one color and applying heat energy to the other color developing layer provided on the other surface of the base material, another color can be developed.

[0031]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional configuration diagram showing one embodiment of a thermosensitive recording medium according to the present invention. As shown in the drawing, the thermosensitive recording medium 1 has a sheet-like substrate 2 made of a transparent resin film such as polyethylene terephthalate (PET), and a red color is formed on one surface of the substrate 2. The layer 3 is formed on the entire surface, and the black coloring layer 4 is formed on the other surface on the other surface.

Here, the coloring characteristics of the red coloring layer 3 and the black coloring layer 4 are shown in FIG. In the figure, the vertical axis indicates the degree of color development, and the horizontal axis indicates the heat energy applied. Since the red coloring layer 3 and the black coloring layer 4 have such characteristics, a low thermal energy EL is applied to the red coloring layer 3 to cause the red coloring layer 3 to develop a color, while the black coloring layer 4 has a high thermal energy. By applying EH to cause the black coloring layer 4 to develop color, it is possible to perform recording in red on one side of the thermosensitive recording medium 1 and recording in black on the other side.

Each of the coloring layers 3 and 4 is formed of a transparent color at room temperature, and when heat energy for developing each color is applied, a portion to which the heat energy is applied is applied to each color. It is made to develop colors.

Next, a case where recording is performed on both surfaces of the thermal recording medium 1 shown in FIG. 1 by a thermal printer will be described.

As shown in FIG. 3, the thermal printer is provided with a control section 11 for controlling the driving of each section of the thermal printer.
An energization control unit 12 and a second energization control unit 16 are provided. Further, the control unit 11 includes an RO of an appropriate capacity.
A memory 18 formed of M, RAM, or the like is installed. The memory 18 has a current value for obtaining a low heat energy EL for coloring the red coloring layer 3 and a high current value for coloring the black coloring layer 4. An energization value for obtaining the heat energy EH is stored.

The thermal printer is provided with a first recording means 6 and a second recording means 7. The first recording means 6 is provided with a first thermal head 9, and a plurality of heating elements 10 are arranged on the first thermal head 9. The first thermal head 9 is connected to the first power supply controller 11. Further, a second thermal head 14 is provided in the second recording means 7, and the second thermal head 1 is provided.
4, a plurality of heating elements 15 are arranged. Then, each heating element 15 of the second thermal head 14
Are connected to the second power supply controller 16.

The first energization control unit 12 controls the low heat energy EL for causing the memory 18 to emit the red coloring layer 3.
An electric current value for obtaining the electric current is extracted, and electric current is supplied to each of the heating elements 10 arranged on the first thermal head 9 based on the electric current value. In addition, the second
The energization control unit 16 derives an energization value for obtaining high heat energy EH for coloring the black coloring layer 4 from the memory 18, and based on the energization value for each heating element 15 arranged in the second thermal head 14. The power is supplied.

The other configuration of the thermal printer is the same as that of the above-described conventional thermal printer, and thus a detailed description is omitted.

Next, the operation of the present embodiment will be described.

First, a plurality of thermosensitive recording media 1 are placed in such a manner that the red coloring layer 3 of the thermosensitive recording medium 1 faces the first thermal head 9 provided in the first recording means 6 and the black coloring layer 4 is 2
It is placed on a paper feed tray (not shown) so as to face the second thermal head 14 installed on the recording means 7. And
When the recording information is input to the control unit 11, the thermal printer starts recording.

First, the heat-sensitive recording medium 1 is
Transported to When the leading end of the thermosensitive recording medium 1 reaches a paper transport mechanism (not shown) of the first recording means 6, the thermosensitive recording medium 1 is moved by the paper transport mechanism.
The recording start position of the thermosensitive recording medium 1 is conveyed to a position where it contacts the first thermal head 9. At this time, the first energization control unit 6 derives an energization value for obtaining a low thermal energy EL from the memory 18 and selectively turns on the heating element 10 of the first thermal head 9 based on the energization value based on the recorded information. To generate heat.

Next, after the recording in the first recording means 6 is completed, the thermosensitive recording medium 1 is transported to the second recording means 7 by the paper transport mechanism of the first recording means 6. When the leading end portion of the thermal recording medium 1 reaches a paper transport mechanism (not shown) of the second recording means 7, the recording start position of the thermal recording medium 1 is changed by the paper transport mechanism. The sheet is transported to a position where it contacts the second thermal head 14. At this time, the second energization control unit 16 derives an energization value for obtaining high thermal energy EH from the memory 18 and based on the record information, the second thermal head 1
The fourth heating element 15 is selectively heated based on the current value.

After the recording is completed in the second recording means 7, the paper transport mechanism of the second recording means 7
The thermosensitive recording medium 1 is conveyed downstream of the second recording means 7, and the recording ends.

In this embodiment, the thermosensitive recording medium 1 in which the red coloring layer 3 is laminated on one surface of the substrate 2 made of a transparent sheet and the black coloring layer 4 is laminated on the other surface of the substrate 2 is used. By using the first recording unit 6, the red coloring layer 3 can be colored by applying a low heat energy EL to the red coloring layer 3. On the other hand, in the second recording means 7, the high thermal energy EH is applied to the black coloring layer 4 of the thermosensitive recording medium 1.
, The black coloring layer 4 can be colored.

Therefore, red recording can be performed on the surface of the thermosensitive recording medium 1 on the red coloring layer 3 side, while black recording can be performed on the surface on the black coloring layer 4 side. Also,
Since the base material 2 of the thermal recording medium 1 is transparent and can be visually recognized through one surface of the thermal recording medium 1 through the other surface, the red and black 2 A color record can be obtained.

Further, in the present embodiment, since recording is performed using the thermosensitive recording medium 1, even when a color image is to be recorded, it is not necessary to use an ink ribbon as in the prior art. It is possible to prevent the printer mechanism from being complicated by selecting the ink ribbon for each time, and it is not necessary to discard the used ink ribbon, so that the amount of dust can be reduced. As a result, a color image can be efficiently recorded.

Next, a second embodiment of the thermosensitive recording medium of the present invention will be described with reference to FIG.

As shown in the figure, the thermosensitive recording medium 20 according to the present embodiment has the same base material 21 as in the first embodiment. A yellow coloring layer 22 is laminated on one entire surface (the A surface shown in FIG. 4) of the substrate 21, and a cyan coloring layer 2 is formed on the entire surface side of the yellow coloring layer 22.
3 are stacked. Further, a yellow coloring layer 24 is laminated on the entire other surface (the surface B shown in FIG. 4) of the base material 21, and a magenta coloring layer 25 is formed on the entire surface side of the yellow coloring layer 24. It is laminated.

Here, the yellow coloring layers 22, 24,
FIG. 2 shows the coloring characteristics of the cyan coloring layer 23 and the magenta coloring layer 25. As shown in the figure, the yellow coloring layers 22 and 24 are colored by applying a high heat energy EH, and the cyan coloring layer 23 and the magenta coloring layer 25 are provided by a low heat energy EL. It has the property of developing color. For this reason, a high thermal energy EH is applied to the yellow coloring layers 22 and 24, while a low thermal energy EL is applied to the cyan coloring layer 23 and the magenta coloring layer 25, so that the yellow color is applied to the A side of the thermosensitive recording medium 20. And cyan, and yellow and magenta on the B side.

Also in this embodiment, each coloring layer 2
2, 23, 24, and 25 are formed of transparent colors at room temperature, and when heat energy for each color is applied, the portion to which the heat energy is applied is colored in each color. Has been made.

Next, a case where recording is performed on both surfaces of the thermosensitive recording medium 20 shown in FIG. 4 by a thermal printer will be described.

In the memory of the thermal printer used in the present embodiment, a current value for obtaining high heat energy EH for coloring the yellow coloring layers 22 and 24, and the cyan coloring layer 23 and the magenta coloring layer 25 are colored. A current value for obtaining low heat energy EL is stored.

The first and second energization control units first extract an energization value for obtaining high thermal energy EH for coloring the yellow coloring layers 22 and 24 from the memory, and dispose them on the first thermal head. The power is supplied to each of the generated heating elements and each of the heating elements arranged in the second thermal head based on the current value. Further, the first energization control section includes a yellow coloring layer 2.
After the color No. 2 is developed, an energization value for obtaining a low heat energy EL for coloring the cyan color developing layer 23 is extracted from the memory, and energization is performed on each heating element of the first thermal head based on the energization value. It has been made like that. Further, after the second energization control section causes the yellow coloring layer 24 to develop a color, the second energization control section draws an energization value for obtaining a low thermal energy EL that causes the magenta coloring layer 25 to develop a color from the memory, and generates each heating value of the second thermal head. The element is energized based on the energization value.

The other configuration of the thermal printer is the same as that of the thermal printer used in the above-described first embodiment, and thus a detailed description is omitted.

Next, the operation of the present embodiment will be described.

First, a plurality of thermosensitive recording media 20 are placed in such a manner that the side A of the thermosensitive recording medium 20 faces the first thermal head provided in the first recording means and the side B is provided in the second recording means. Placed on the paper feed tray so as to face the second thermal head.

First, when the recording start position of the thermosensitive recording medium 20 is conveyed to a position where it comes into contact with the first thermal head, the first energization control section reads the yellow coloring layer 22 from the memory.
An energizing value for obtaining high thermal energy EH for developing the color is extracted, and the heating element of the first thermal head is selectively heated based on the energizing value based on the recording information.

Next, when the recording start position of the thermosensitive recording medium 20 is conveyed to a position where it comes into contact with the second thermal head, the second energization control section supplies high thermal energy EH for coloring the yellow coloring layer 24 from the memory. An energization value for obtaining is obtained, and the heating element of the second thermal head is selectively heated based on the energization value based on the recording information.

Next, after the recording of the yellow coloring layer 24 on the side B by the second recording means is completed, the paper transport mechanisms of the second recording means and the first recording means are driven to reverse. Thereby, the heat-sensitive recording medium 20 is
Is fed back to a position where the tip portion of the head comes into contact with the first thermal head.

Next, the first energization control unit derives from the memory an energization value for obtaining a low thermal energy EL for coloring the cyan coloring layer 23, and activates the heating element of the first thermal head based on the recorded information. Recording is performed while selectively generating heat based on.

Further, when the recording start position of the thermosensitive recording medium 20 is conveyed to a position where it comes into contact with the second thermal head, the second energization control section reads the magenta coloring layer 25 from the memory.
An electric current value for obtaining a low thermal energy EL for coloring is drawn, and recording is performed while selectively causing the heating element of the second thermal head to generate heat based on the electric current value based on the recording information.

After the recording is completed in the second recording means, the thermosensitive recording medium 20 is conveyed downstream from the second recording means, thereby completing the recording.
Note that other recording methods are the same as those in the first embodiment, and a description thereof will be omitted.

In the present embodiment, the thermosensitive recording medium 20 has a yellow coloring layer 22 and a cyan coloring layer 23 laminated on the A side of a substrate 21 made of a transparent sheet.
On the B side, a yellow coloring layer 24 and a magenta coloring layer 25 are laminated. Then, in the first recording means and the second recording means, the yellow coloring layer 22 on the A side and the B side,
By giving the high heat energy EH to the yellow coloring layers 24, the yellow coloring layers 22, 24 can be colored. Further, by applying a low heat energy EL to the cyan coloring layer 23 in the first recording means, the cyan coloring layer 23 is colored, and by applying a high thermal energy EH to the magenta coloring layer 25 in the second recording means. The magenta coloring layer 25 can be colored.

Accordingly, it is possible to perform recording in yellow and cyan on the surface A of the thermosensitive recording medium 20, while performing recording in yellow and magenta on the surface B. The base material 2 of the thermosensitive recording medium 20
1 is transparent so that it can be viewed from one side of the thermosensitive recording medium 20 through the other side, so that yellow, cyan, magenta, and 3 By mixing the colors, a color image record can be obtained.

Note that the recording method for the thermosensitive recording medium 20 of the present embodiment is not limited to this. For example, after the recording of the yellow coloring layer 22 on the side A by the first recording unit, the thermosensitive recording medium 20 is reversely fed by the paper transport mechanism of the first recording unit, and the leading end portion of the thermosensitive recording medium 20 is Is transported to a position where it contacts the first thermal head. Then, the first recording means records the cyan coloring layer 23 on the A side. Next, the first
The thermosensitive recording medium 20 is conveyed to the second recording means by the paper conveyance mechanism of the recording means, and the second recording means records the yellow coloring layer 24 on the side B, and then the paper conveyance mechanism of the second recording means The heat-sensitive recording medium 20 is transported in the reverse direction, and is conveyed to a position where the leading end of the heat-sensitive recording medium 20 comes into contact with the second thermal head. Then, the second recording means may record the magenta coloring layer 25 on the B side.

The heat-sensitive recording medium of the present invention is not limited to the heat-sensitive recording medium in each of the above-described embodiments, and various other heat-sensitive recording media can be considered.

For example, as shown in FIG. 5, the heat-sensitive recording medium 27 has sheet-like base materials 28a and 28b made of a pair of transparent resin films.
A yellow coloring layer 30 is formed between the entirety of 28b. In addition, a cyan coloring layer 31 is laminated on the entire surface of one of the substrates 28a and 28b, and the entire surface of the other substrate 28b is
A magenta coloring layer 32 is formed by lamination.

According to the thermosensitive recording medium 27, since the color-forming layers 30, 31, and 32 of each color are separated by the bases 28a and 28b, the color-forming layers 30, 31, and 32 are preferably mixed without mixing. A color image record can be obtained.

As shown in FIG. 6, another thermal recording medium 34 has a substrate 35 made of a transparent resin film, and one surface of the substrate 35 (the C surface shown in FIG. 6). A black coloring layer 36 is laminated on the entire surface of the substrate, and a cyan coloring layer 37 is laminated on the entire surface of the black coloring layer 36. Further, the other surface of the base material 35 (D shown in FIG. 6)
A yellow coloring layer 38 is laminated on the entire surface (surface), and a magenta coloring layer 39 is laminated on the entire surface of the yellow coloring layer 38.

In this case, the black coloring layer 36 has a property of coloring with the same high thermal energy EH as the yellow coloring layer 38.

According to the heat-sensitive recording medium 4, the heat-sensitive recording medium 34 can be viewed from one surface through the other surface, and can be viewed on the heat-sensitive recording medium 34 in yellow, cyan, magenta, By mixing black and the above four colors, a full-color image can be recorded.

Further, as shown in FIG. 7, another heat-sensitive recording medium 41 has a base material 42 made of a transparent resin film, and one surface of the base material 42 (the E surface shown in FIG. 7). A black coloring layer 43 is laminated on the entirety of. A sheet 44a made of a transparent resin film is laminated on the entire surface of the black coloring layer 43.
The cyan coloring layer 45 is laminated on the entire surface of the. Further, the other surface of the base material 42 (F shown in FIG. 7)
A yellow coloring layer 46 is laminated on the entire surface (the surface). In addition, the entire surface of the yellow coloring layer 46
A sheet 44b made of a transparent resin film is laminated, and a magenta coloring layer 47 is laminated on the entire surface of the sheet 44b.

According to the thermosensitive recording medium 41, since the coloring layers 43, 45, 46 and 47 of the respective colors are separated by the base material 42 and the sheets 44a and 44b, the coloring layers 4
Good full-color image recording can be obtained without mixing 3, 45, 46 and 47.

The present invention is not limited to the above-described embodiment, but can be variously modified as needed.

[0075]

As described above, according to the thermal recording medium of the present invention, one color can be recorded on one surface of the thermal recording medium, and the other color can be recorded on the other surface. Color recording can be performed. Further, since the base material is transparent and can be visually recognized through one surface of the heat-sensitive recording medium through the other surface, it is possible to obtain two-color image recording on the heat-sensitive recording medium. it can.

According to another heat-sensitive recording medium according to the present invention, the heat-sensitive recording medium can be visually recognized through one surface from the other surface, whereby a yellow color is formed on the heat-sensitive recording medium. , Cyan, magenta, and a mixture of the three colors, a color image can be recorded.

Further, according to another heat-sensitive recording medium of the present invention, the heat-sensitive recording medium can be visually recognized by passing through from one surface to the other surface. By mixing the colors, cyan, magenta, black, and the four colors, a full-color image can be recorded.

Further, according to another heat-sensitive recording medium according to the present invention, since the color-forming layers of each color are separated by each base material, a good color image can be recorded without mixing the color-forming layers. be able to.

According to another heat-sensitive recording medium according to the present invention, the heat-sensitive recording medium can be visually recognized by passing through from one surface to the other surface, and yellow and cyan colors can be displayed on the heat-sensitive recording medium. , Magenta, black, and the above four colors can be mixed to obtain a full-color image. In addition, since the color-forming layers of each color are separated by each base material, a good full-color image can be recorded without mixing the color-forming layers.

Further, according to the thermal printer of the present invention, it is possible to record one color on one surface of the thermosensitive recording medium and record the other color on the other surface. Can be. In addition, since the base material is transparent, which allows the heat-sensitive recording medium to be visually recognized through one surface from the other surface, it is possible to obtain an image of two or more colors on the heat-sensitive recording medium. Can be.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a thermosensitive recording medium according to the present invention.

FIG. 2 is a graph showing coloring characteristics of a red coloring layer and a black coloring layer of the thermosensitive recording medium shown in FIG.

FIG. 3 is a conceptual diagram showing an embodiment of a control unit in the thermal printer according to the present invention.

FIG. 4 is a sectional view showing another embodiment of the thermosensitive recording medium according to the present invention.

FIG. 5 is a sectional view showing another embodiment of the thermal recording medium according to the present invention.

FIG. 6 is a sectional view showing another embodiment of the thermal recording medium according to the present invention.

FIG. 7 is a sectional view showing another embodiment of the thermosensitive recording medium according to the present invention.

FIG. 8 is a schematic front view showing a conventional thermal printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thermal recording medium 2 Base material 3 Red coloring layer 4 Black coloring layer 6 1st recording means 7 2nd recording means 9 1st thermal head 10 Heating element 11 Control part 12 First conduction control part 14 Second thermal head 15 Heating element 16 second energization control unit 18 memory

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) B41M 5/18 MF Term (Reference) 2C055 KK00 KK02 KK04 KK05 KK06 2H026 AA07 AA14 AA28 EE05 FF07 FF17

Claims (6)

[Claims] 1. A heat-sensitive recording medium comprising a base material made of a transparent sheet and a color-forming layer for forming different colors on both surfaces. 2. A method according to claim 1, further comprising: laminating, on one side of a base material made of a transparent sheet, a yellow coloring layer that develops color with predetermined heat energy and a cyan coloring layer that develops color with lower heat energy than the yellow coloring layer. A heat-sensitive recording medium, comprising the yellow color-forming layer and a magenta color-forming layer that develops with lower thermal energy than the yellow color-forming layer on the other surface of the substrate. 3. A method according to claim 1, further comprising: laminating, on one surface of a substrate made of a transparent sheet, a yellow coloring layer that develops color with predetermined heat energy and a cyan coloring layer that develops color with lower heat energy than the yellow coloring layer. On the other surface of the substrate, a heat-sensitive layer characterized by laminating a black color-forming layer that forms color with substantially the same thermal energy as the yellow color-forming layer and a magenta color-forming layer that forms color with substantially the same thermal energy as the cyan color-forming layer. recoding media. 4. A yellow coloring layer which develops color with a predetermined thermal energy is formed between two transparent sheets, and a color is developed on the surfaces of the two substrates with a lower thermal energy than the yellow coloring layer, respectively. A thermosensitive recording medium comprising a cyan coloring layer and a magenta coloring layer. 5. A method according to claim 1, further comprising: laminating, on one surface of a substrate made of a transparent sheet, a yellow coloring layer which develops color with a predetermined heat energy; laminating a film made of a transparent sheet on the surface of the yellow coloring layer; A cyan coloring layer that develops with a lower thermal energy than the yellow coloring layer is laminated on the surface of the substrate, and a black coloring layer that develops with substantially the same thermal energy as the yellow coloring layer is formed on the other surface of the substrate. Laminated, on the surface of the black coloring layer, laminated a film made of a transparent sheet, on the surface of the film, laminated a magenta coloring layer that develops a lower heat energy compared to the black coloring layer. Characterized thermal recording medium. 6. A first thermal head for performing printing on a front surface of a recording medium to be conveyed, a second thermal head for performing printing on a back surface, and the first thermal head being press-contacted via the recording medium. A first platen, a second platen against which the second thermal head presses through the recording medium, a paper transport mechanism for transporting the recording medium, the first thermal head and the second thermal head. 6. The recording medium according to claim 1, further comprising a control unit configured to control a heating temperature of the head to at least a first heating temperature and a second heating temperature higher than the first heating temperature.
First, the first and second thermal heads are driven at the first heating temperature to perform recording, and thereafter, the first and second thermal heads are moved to the second thermal head. A thermal printer characterized in that it is controlled to perform recording by driving at a heat generation temperature.