JPH09123492A - Color thermal printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform proper controlling by easily discriminating a continuous type recording material from a cut-sheet type recording material. SOLUTION: By arranging a yellow thermal head 14, a magenta thermal head and a cyan thermal head in the order named along the passing region of a color heat-sensitive recording material 10, a full color image is recorded through one time movement of the color heat-sensitive recording material 10. A tip sensor 71 and a mark sensor 74 are provided near the thermal head 14. The recording material 10 is carried by a pair 41 of carrying rollers. Position marks are formed on a continuous type recording material 10 at a specified pitch. A pair 41 of the carrying roller is rotated by a pulse motor 43. When the positioning marks are detected by the mark sensor 74 within a certain fixed period of time, a recording material concerned is judged as a continuous type one. When no positioning mark is detected within a certain fixed period of time after the detection of the tip of a recording material concerned by the tip sensor 71, the recording material concerned is judged as a cut-sheet type one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color thermal printer, and more particularly to a color thermal printer for recording full-color images on both long type and cut sheet type recording materials without color misregistration.

[0002]

2. Description of the Related Art Thermal printers include thermal transfer printers and thermal printers. In the former thermal transfer printer,
There are a melt type and a sublimation type. These are a type in which an ink film is superposed on a recording paper, a thermal head is pressed against the back of the ink film to heat it, and the ink of the ink film is transferred to the recording paper. An area gradation method that changes the ink application area according to the gradation data is adopted when a full-color image is recorded by the fusion type, and heat is generated according to the gradation data when a full-color image is recorded by the sublimation type. A gradation heating method that changes the amount is adopted. In the latter thermal printer, the thermal recording paper is heated by a thermal head to color the thermal recording paper to thermally record ink dots, and a gradation heating method is adopted.

A color thermal printer uses a color thermal recording material that develops color by heating. The thermal head presses and heats the color thermal recording material while moving the thermal head and the color thermal recording material relative to each other to form a full color image. Record. In this color thermosensitive recording material, at least a cyan thermosensitive coloring layer, a magenta thermosensitive coloring layer, and a yellow thermosensitive coloring layer are sequentially formed on a base. In order to selectively color each thermosensitive coloring layer, the thermosensitive coloring layers have different thermal sensitivities, the thermal sensitivity of the cyan thermosensitive coloring layer at the bottom is the lowest, and the thermal sensitivity of the yellow thermosensitive coloring layer at the top. Highest sensitivity. Further, when recording the next thermosensitive coloring layer, electromagnetic radiation peculiar to the recorded thermosensitive coloring layer is irradiated and fixed so that the recorded thermosensitive coloring layer thereon is not recorded again.

A large number of heating elements are formed in a line on the thermal head, and an image of one color is recorded line by line. When recording this one line, each heating element applies color-developing heat energy (mJ / mm ² ) based on the characteristic curve of the thermosensitive color-developing layer to be recorded to the color thermosensitive recording material,
On the color thermosensitive recording material, dots are formed by coloring the inside of the pixels virtually divided into squares. This coloring heat energy is the heat energy immediately before the thermosensitive coloring layer to be recorded (hereinafter referred to as bias heat energy) and the heat energy for causing a desired density (hereinafter referred to as gradation heat energy). That is) and. The bias heat energy is a constant value determined according to the type of the thermosensitive coloring layer, but the gradation heat energy changes according to the image data representing the gradation level.

In order to perform high-speed printing, three thermal heads are arranged in the passage area of the recording material, and while the recording material is passed once from the upstream side to the downstream side, a yellow image and a magenta image are formed by each thermal head. There is known a 1-pass 3-head type color thermal printer that sequentially records cyan images to form a full-color image (for example, Japanese Patent Laid-Open No. 5-201043 and Japanese Patent Publication No. 6-96338).

[0006]

In such a conventional 1-pass 3-head type color thermal printer, as the color thermal recording material, a long type wound in a roll and housed and a cut sheet type are used. You can However, when two types of recording materials were to be used in the same color thermal printer, it was necessary to detect each type by some means and change the control.

The present invention is to solve the above problems, and provides a color thermal printer capable of easily discriminating between a long type and a cut sheet type and performing an appropriate control. To aim.

[0008]

In order to achieve the above object, a color thermal printer according to a first aspect of the present invention comprises a front end sensor for detecting the front end of a recording material and a positioning mark formed at a predetermined pitch on the recording material. A mark sensor for detecting, a feed amount equivalent value detecting unit for detecting a recording material feed amount equivalent value in the recording material conveying unit, a recording material form determining unit for determining whether the recording material is a long type or a cut sheet type, A first recording position of the thermal head is specified based on a mark detection signal from the mark sensor and a feed amount equivalent value from the feed amount equivalent value detection unit when the material form determining unit determines the long type. The leading edge detection signal from the leading edge sensor and the feed amount equivalent value detection when the position specifying unit and the recording material form determination means determine the cut sheet type It is obtained by a second position specifying section for specifying the recording start position of the thermal head based on the feed amount equivalent value from the stage. The recording material form determination means determines that the recording material is a long type when the positioning mark is detected by the mark sensor within a fixed time, and positions the recording material within a fixed time after the tip is detected by the tip sensor. It is preferable to determine that the recording material is a cut sheet type when no mark is detected. Further, it is preferable that the recording material form determining means is composed of a recording material detection sensor which is attached to a recording material supply mechanism and detects each type of recording material. Also,
It is preferable that the recording material form determination means is composed of input means for inputting the type of recording material.

[0009]

FIG. 2 shows a linear movement type color thermal printer embodying the present invention. Three platen rollers 11, 12 and 13 are rotatably arranged at appropriate intervals along the pass area of the color thermosensitive recording material 10. A thermal head 14 for yellow, a thermal head 15 for magenta, and a thermal head 16 for cyan are disposed on each of the platen rollers 11 to 13 so as to face each other. , Cyan print stage 19 are formed.

A recording material supply mechanism 20 is arranged on the upstream side of the yellow print stage 17 in the recording material feeding direction. The supply mechanism 20 includes a roll holding unit 21, a sheet setting unit 22, and a paper feeding unit 23 that selectively sends a recording material from them. Roll holder 2
1 includes two holding rollers 21a, and these holding rollers 21a rotatably hold the roll-shaped color thermosensitive recording material 10. In the sheet setting section 22,
The color thermosensitive recording material 10a in the form of a cut sheet is manually set.

The paper feeding section 23 comprises a paper feeding roller pair 24 and drawing roller pairs 25 and 26 for selectively feeding the color thermosensitive recording materials 10 and 10a into the paper feeding roller pair 24. These roller pairs 24-26 are drive rollers 24a,
25a, 26a and pressing rollers 24b, 25b, 26b
The drive rollers 24a to 26a are rotationally driven by a pulse motor 27. Each pressing roller 2
4b to 26b are urged so as to be pressed against the drive rollers 24a to 26a. The pressing rollers 25b and 26b are biased lighter than the pressing roller 24b, and are mainly conveyed by the paper feed roller pair 24.

In the feeding mechanism 20, one of the roll holding portion 21 and the sheet setting portion 22 is selected by a signal from a system controller 28 (see FIG. 1) described later, and the pull-in roller pair 25 or 26 on the selected side is selected. By rotating, one of the long type color thermosensitive recording material 10 and the cut sheet type color thermosensitive recording material 10a is nipped by the pair of paper feed rollers 24 and sent to the yellow print stage 17. Therefore, a keyboard 29 is connected to the system controller 28 so that the form type of the recording material can be input. In addition to the designation of the type by the keyboard 29, a long type is initially set, and when a cut sheet type recording material 10a is set in the sheet setting section 22, this is set by a sensor (not shown). It is also possible to detect and automatically switch to the cut sheet type.

A cutter 30 is arranged on the downstream side of the drawing roller pair 25 in the recording material conveying direction so that the long type recording material 10 is cut by the cutter 30 when the set number of prints is reached. Has become. Therefore, a mark sensor (not shown) detects a positioning mark 31 (see FIG. 4), which will be described in detail later, and the long type recording material 10 is cut at a predetermined position with reference to the positioning mark 31.

On the print stages 17 to 19, the recording material conveying parts 35, 36, 37 and the thermal heads 1 are provided.
4 to 16 are provided, and recording units 38, 39 and 40 (see FIG. 1) for recording each color image on the recording material are provided,
These are controlled by the system controller 28.

As shown in FIG. 1, the yellow carrying section 35.
Is composed of a conveying roller pair 41, an auxiliary roller pair 42, a pulse motor 43 for rotating these, a motor drive circuit 44, a first position specifying section 45, and a second position specifying section 46. Magenta transport unit 36 and cyan transport unit 37
Is also configured similarly to the yellow transport unit 35, and only blocks are shown. The motor drive circuit 44 is
It is composed of a driver 44a and a motor controller 44b. The motor controller 44b generates a drive pulse at a predetermined rate based on the drive signal from the system controller 28.

The pair of conveying rollers 41 is the platen roller 11
The color thermosensitive recording material 10 is arranged in the vicinity of the downstream side in the conveying direction. The conveyance roller pair 41 is a pinch roller 41.
It is composed of a and a capstan 41b, and the capstan 41b is rotationally driven by a pulse motor 43. The capstan 41b is horizontally attached to a machine frame (not shown). As shown in FIG. 3, the pinch roller 41
A is horizontally attached to the swing frame 50. The rocking frame 50 is rocked by a cam 51 around the mounting shaft 52 at a constant angle. In addition, the swing frame 50 uses the coil spring 53 for the pinch roller 4
1a is urged so as to be pressed against the capstan 41b side. As a result, the pinch roller 41a is normally pressed against the capstan 41b, and the color thermosensitive recording material 10 is sandwiched between the pinch rollers 41a. When the tip of the color thermosensitive recording material 10 passes,
When the cam 51 rotates by a predetermined angle, the swing frame 5
0 is rotated by a predetermined angle, so that the capstan 41b
The pinch roller 41a is separated from the to and the tip of the color thermosensitive recording material 10 is passed through this gap. A roller shift mechanism 54 is configured by the swing frame 50, the cam 51, and the coil spring 53. Similarly, the pair of transport rollers 41 in the other print stages 18 and 19 is also provided with the roller shift mechanism 54 so that the nip and the nip release of the color thermosensitive recording material 10 are selectively performed. The roller shift mechanism 54 is only required to be able to shift the pinch roller 41a or the capstan 41b, and may be of a type in which the roller shaft is directly shifted by a cam or solenoid.

As shown in FIG. 3, the auxiliary roller pair 42 includes
It is arranged near the platen roller 11 on the upstream side in the transport direction of the color thermosensitive recording material 10. Auxiliary roller pair 42
Is composed of an auxiliary roller 42a and a pressing roller 42b, and the pressing roller 42b is the roller shift mechanism 5.
It is lightly urged toward the auxiliary roller 42a side by 5, and the color thermosensitive recording material 10 is lightly nipped. Further, the auxiliary roller 42a is rotated by the pulse motor 43 that rotates the capstan 41b so as to have the same conveyance speed as the capstan 41b. The roller shift mechanism 55 has substantially the same structure as the roller shift mechanism 54. The pressing roller 42b is also the roller shift mechanism 55.
As a result, a transition is made between the guide position in pressure contact with the auxiliary roller 42a and the retracted position away from the auxiliary roller 42a. Then, when the front end of the color thermosensitive recording material 10 is passed, the pressing roller 42b is moved to the retracted position by the roller shift mechanism 55. Similarly, the auxiliary roller pair 42 in the other print stages 18 and 19 is also provided with the roller shift mechanism 55 so that the nip and the nip release of the color thermosensitive recording material 10 are selectively performed.

As shown in FIG. 2, the thermal head 14-
16 includes heating element arrays 14a, 15a, 16a in which a large number of heating elements are arranged in a line, and these extend in the axial direction (main scanning direction) of the platen rollers 11-13. Further, as shown in FIG. 3, a radiation fin 58 is attached to the thermal head 14. Similarly, radiation fins are attached to the other thermal heads 15 and 16.

A roller shift mechanism 60 is provided on the platen roller 11. The roller shift mechanism 60 includes a swing frame 61, a cam 62, and a coil spring 63, and the basic configuration is the same as that of the roller shift mechanism 54. The swing frame 61 is attached to the mounting shaft 64 by the cam 62.
It is designed to oscillate at a constant angle around. The swing frame 61 is biased by a coil spring 63, and normally the platen roller 11 is the thermal head 1.
No. 4 heating element array 14a. And
When the leading edge of the color thermosensitive recording material 10 passes or when printing of one frame when the cut sheet is selected is finished,
When the cam 62 rotates by a predetermined angle, the swing frame 6
1 is rotated by a predetermined angle, so that the heating element array 14
The pressure contact of the color thermosensitive recording material 10 to a is released. The other platen rollers 12 and 13 are also the platen roller 1
It is constructed in the same manner as 1.

As shown in FIG. 2, between the yellow thermal head 14 and the magenta thermal head 15,
A yellow fixing device 65 is arranged. The yellow fixing device 65 includes an ultraviolet lamp 66 that emits near ultraviolet light having an emission peak of 420 nm and a reflector 67. Further, a magenta fixing device 68 is arranged between the magenta thermal head 15 and the cyan thermal head 16. This magenta fixing device 68
Is composed of an ultraviolet lamp 69 that emits near-ultraviolet light having an emission peak of 365 nm and a reflector 70.

As shown in FIG. 2, the tip sensors 71, 72, 73 and the mark sensors 74, 75, 76 are provided near the auxiliary roller pairs 42 and on the downstream side in the color thermosensitive recording material conveying direction.
And are arranged. As shown in FIG. 1, the tip sensor 7
Reference numeral 1 denotes a transmissive sensor including a light projector 71a and a light receiver 71b, and detects the tip of the color thermosensitive recording material 10. The other tip sensors 72 and 73 are also configured in the same manner as the tip sensor 71. In addition, the mark sensor 74
.. to 76 are composed of reflection type sensors having a light projecting portion and a light receiving portion, and these mark sensors 74 to 76 are positioning marks formed on the recording material 10 at a predetermined pitch L1 as shown in FIG. 31 is detected.

The positioning mark 31 is recorded by printing on the surface of the color thermosensitive recording material 10 opposite to the surface on which the thermosensitive recording layer is formed. The positioning marks 31 are formed at a ratio of one to one recording area PA corresponding to the recording area PA, and the pitch thereof is L1. Incidentally, a plurality of positioning marks may be recorded in one recording area by reducing the pitch so as to correspond to the size change of the recording area PA. In this case, recording is performed according to the number of detected positioning marks. The area PA is specified.

As shown in FIG. 1, the detection signal of the mark sensor 74 is sent to the first position specifying section 45. Further, the detection signal of the tip sensor 71 is sent to the second position specifying unit 46.
The number of drive pulses of the pulse motor 43 is input to the first and second position specifying units 45 and 46, and the number of pulses is counted by the counter 82. At that time, after resetting the counter 82 based on the mark detection signal or the tip detection signal, the number of pulses is counted, and this count value is compared with a comparison value determined in advance by the coincidence detection circuit 83, and these are When they match, each position such as the thermal head pressure-bonding start position, recording start position, recording end position, and thermal head pressure-bonding release position is specified. The comparison value is predetermined for each specific position, and this is the memory 28a.
Is stored in In the present embodiment, the number of drive pulses of the pulse motor 43 is used as the feed amount equivalent value, but in addition to this, the signal of the rotary encoder that rotates in association with the feeding of the recording material is used as the feed amount equivalent value. May be. Furthermore, when the recording material 10 is fed at a constant speed, the time required for feeding may be set as the feed amount equivalent value.

The positioning mark detection signal from the mark sensor 74 is sent to the mark detection processing circuit 86 via the sensor drive detection circuit 85, where the mark detection signal is extracted, and the mark detection signal is extracted from the counter 82 and the system controller. Sent to 28. In the mark sensor 74, the sensor drive detection circuit 85 causes the light emitting LEDs to have an interval shorter than the length L2 of the constant cycle (see FIG. 4).
Each time it is driven, the mark detection signal from the light receiving section is amplified and sent to the mark detection processing circuit 86.

Further, the system controller 28 selects the first or second position specifying portion 45 or 46 according to the signal input when the type of the recording material is selected by the supply mechanism 20, and in the case of the long type. The position of the recording material 10 is specified by the first position specifying section 45 based on the mark detection signal of the mark sensor 74, and the cut sheet type recording material 1
In the case of 0a, the tip sensor 7 is detected by the second position specifying unit 46.
The position of the recording material 10a is specified based on the recording material leading edge detection signal of No. 1.

That is, in the case of the long type, by counting the motor drive pulse of the pulse motor 43 from the time when the positioning mark 31 is detected by the mark sensor 74, the color thermosensitive recording material 10 on the yellow print stage 17 is recorded. The recording area PA is tracked and the recording start position SP and the like are specified. By using this tracking result, the platen roller 11 is raised to press the recording material onto the heating element array 14a and control the energization of each heating element. The other magenta print stage 18 and cyan print stage 19 are controlled in the same manner.

In the case of the cut sheet type recording material 10a, the color thermosensitive recording material 10 from the tip sensor 71 is used.
By counting the number of drive pulses of each pulse motor 43 based on the tip detection signal of a, the thermal head 14
The printing start control is performed in the same manner as in the long type by specifying the pressure-bonding start position of and the recording start position of the recording material 10a. The other magenta print stage 18 and the cyan print stage 19 are similarly processed in the same manner as the tip sensors 72, 7
It is controlled based on the detection signal of 3.

Then, the system controller 28 operates each of the recording sections 38 to 40 based on the detection signal of the positioning mark 31 and the tip of the recording material to record the image of each color line by line by the thermal heads 14 to 16. .
Therefore, the image of each color recorded on each of the print stages 17 to 19 is recorded without color misregistration. Each recording unit 38-
As is well known, 40 heats each heating element by bias and also performs gradation heating according to image data to record an image of each color line by line. Each of the recording units 38 to 40 is disclosed in, for example, JP-A-7-137320 and JP-A-7-144428.
It is configured by using the thermal head drive control device described in Japanese Patent Publication No. After the yellow recording, the yellow thermosensitive recording layer is optically fixed by the yellow fixing device 65. After magenta recording, the magenta thermosensitive recording layer is optically fixed by the magenta fixing device 68. In this way, the yellow, magenta, and cyan thermosensitive recording layers are recorded in the same recording area, and a full-color image is obtained. If the full-color image is of a long type, the positioning mark 31
Based on the detection signal of (3), the image is separated by a cutter (not shown) in the blank area between the images.

Next, the operation of the above embodiment will be briefly described. First, the keyboard 29 is used to input whether the recording material to be used is the long type or the cut sheet type. Next, when a print start switch (not shown) is operated, the system controller 28 causes the yellow fixing device 6 to operate.
5. The color thermosensitive recording material 1 designated by turning on the magenta fixing device 68 and operating the supply mechanism 20.
Paper feeding of 0 or 10a is performed. In another embodiment in which the initial setting is the long type, the cut sheet type recording material 10a of the sheet setting unit 22 is supplied only when the cut sheet type recording material 10a is set in the sheet setting unit 22. The paper unit 23 is sent to the yellow print stage 17. At the time of this paper feeding, the nip of each auxiliary roller pair 42, platen rollers 11 to 13, and each transport roller pair 41 is released.

The color thermosensitive recording material 10 has a supply mechanism 20.
It is conveyed toward the platen roller 11 by the pair of paper feed rollers 24. During this transportation, the system controller 28
Indicates the tip of the color thermosensitive recording material 10 from the tip sensors 71 to 71.
The position of the leading edge of the color thermosensitive recording material 10 is tracked from the number of drive pulses of the pulse motor 27 on the paper feeding side based on the detection signal. Then, based on this tracking result, after the front end of the color thermosensitive recording material 10 passes through the auxiliary roller pair 42 and the conveying roller pair 41, these are sequentially brought into a nip state, and at a predetermined timing, the conveying units 35 to 37 are driven. The pulse motor 43 is rotated.

For example, the system controller 28 instructs the motor drive circuit 44 to rotate the motor at a predetermined timing, and the motor controller 44a of the motor drive circuit 44 is instructed.
Sends a motor drive pulse having a constant cycle to the driver 44b to rotate the pulse motor 43 at a constant speed to drive the conveyance roller pair 41. As a result, the transport roller pair 4
1, the color thermosensitive recording material 10 is conveyed on the yellow print stage 17.

The system controller 28 counts the number of drive pulses of the motor 43 after detecting the positioning mark 31, and identifies the head pressing position and the recording start position SP of the recording area PA based on this count value. And
Based on this, the yellow recording unit 38 is controlled to record the yellow image line by line in the recording area PA.
Similar control is performed in the other print stages 18 and 19, and recording of each color is sequentially performed in each of the print stages 17 to 19.

In the case of the cut sheet type color thermosensitive recording material 10a, the recording start position and the like are specified based on the leading edge detection signal from the leading edge sensor 71 using the second position identifying section 46, and based on these. Then each color is printed.

A slack is formed on the color thermosensitive recording material 10 between the thermal heads 14 to 16, and due to this slack, fluctuations in the transport load due to changes in the behavior of the thermal head in one print stage are transferred to the other print stage. It may not be transmitted.

In the above embodiment, the position specifying units 45 and 46 are configured by hardware using the counter 82, the coincidence detection circuit 83, etc., but in addition to this, they may be implemented by software. Further, in the above embodiment, the cut sheet type recording material 10 is provided in the sheet setting section 22.
Although the second position specifying unit 46 is used when a is set, the position specifying units 45 and 46 to be used may be specified by the keyboard 29 in addition to such automatic switching.

Further, without using the signal from the supply mechanism 20, the long type or the cut sheet type is automatically determined based on the detection signals of the tip sensor 71 and the mark sensor 74 by the processing procedure as shown in FIG. You may do it. In this case, it is determined whether the type is the long type or the cut sheet type by using the positioning mark 31 for the cut sheet type.
Since it is not recorded, it is performed based on the detection of the presence or absence of this. That is, in the case of the long type, the positioning marks 31 are formed at a predetermined pitch as shown in FIG. 4, and the print start position and the cut position are specified based on the positioning marks 31. Therefore, after the tip of the recording material is detected by the tip sensors 71 to 73, a predetermined time T1 (T1 = T2 + T3, T2 is a time obtained by dividing the distance from the tip to the positioning mark by the feed speed, T3).
Is a long type when the positioning mark 31 is detected within a time corresponding to the feed error), and when the positioning mark 31 is not detected even after a predetermined time T1,
Judge as cut sheet type. Further, printing is performed only when the result of morphological determination of the recording material by the tip sensor 71 and the mark sensor 74 and the morphological detection signal from the recording material feeding mechanism or the morphological designation signal from the keyboard match. It may be started and an alarm may be issued in other cases. In this case, it is possible to more accurately detect whether the recording material is a cut sheet or a long sheet.

Further, in the above embodiment, the positioning mark 3
1 is printed on the surface of the color thermosensitive recording material 10 opposite to the thermosensitive recording layer forming side, but the positioning marks may be formed by small holes or notches. Further, a positioning mark may be recorded on the thermosensitive recording layer before printing by thermosensitive recording.

Further, although the color thermal printer has been described in the above embodiment, although not shown in the drawings,
The present invention may be applied to a sublimation type thermal transfer printer using yellow, magenta, and cyan color ink ribbons. In this case, a color ink ribbon is interposed between each heating element array of the thermal head and the recording material,
The ink from each ink ribbon is thermally transferred to the recording material.
Further, a heat melting type may be used instead of the sublimation type.

In each embodiment, the thermal heads 14 to 16 are fixedly arranged and the platen roller 11 is used.
Although the positions of the heating element arrays are not changed by raising and lowering the side of 13 to 13, it is also possible to raise and lower the side of the thermal head. Further, although the platen rollers 11 to 13 are used in the above embodiment, a plastic template may be used instead. In addition, for color thermosensitive recording materials,
A black coloring layer may be formed to have a four-layer structure, or a thermosensitive coloring layer that develops a specific color such as skin color may be added to have a five-layer structure. Further, in FIG. 2, the thermal heads 14 to 16 arranged vertically are used, but in addition to this, JP-A-5-20104 is also used.
A horizontal type thermal head as described in Japanese Patent No. 3 may be used. Although the color thermosensitive recording material is conveyed on a horizontal plane, it may be conveyed on a plane intersecting the horizontal plane, for example, a vertical plane. Also,
In the above-described embodiment, the color thermal printer is used. However, the present invention may be applied to a monochrome thermal printer or a color or monochrome inkjet printer. Further, the present invention may be embodied in a copying machine, a facsimile machine or the like which uses both the long type and the cut sheet type.

[0040]

According to the present invention, the recording material form determining means determines whether the recording material is the long type or the cut sheet type, and when it is determined that the recording material is the long type, the thermal head of the thermal head is detected based on the mark detection signal from the mark sensor. Full-color recording is performed by specifying the recording start position and performing full-color recording, and when it is determined that the type is a cut sheet type, the compression start position and recording start position of the thermal head are specified based on the front end detection signal from the front end sensor. Since the control unit is provided, a full-color image can be recorded on two recording materials of the long type and the cut sheet type.

Further, the recording material form judging means judges that the recording material is a long type when the positioning mark is detected by the mark sensor within a fixed time after the tip is detected by the tip sensor, Since it is determined that the recording material is the cut sheet type when the positioning mark is not detected by the sensor, the form type of the recording material can be specified only from the output of the sensor. Therefore, in the color thermal printer capable of supplying either the long type or the cut sheet type, it becomes possible to specify the form type of these recording materials with a simple configuration without newly adding another sensor or the like.

Further, the form of the recording material can be easily specified by configuring the recording material form determining means in the supply mechanism by the recording material detecting means for detecting the cut sheet type or the long type, respectively. Further, by constituting the input means for inputting the type of recording material, the form of the recording material can be easily specified in the same manner. Further, by using the judgment results of these recording material form judging means in any combination, printing is performed only when these judgment results match, and an alarm is issued without printing otherwise, recording materials of different forms are recorded. Can be surely printed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main part of a color thermal printer embodying the present invention.

FIG. 2 is a schematic view of the same color thermal printer.

FIG. 3 is an enlarged schematic view of a yellow print stage.

FIG. 4 is a plan view showing a positioning mark of a long type color thermosensitive recording material.

FIG. 5 is a flowchart showing a processing procedure in another embodiment.

[Explanation of symbols]

 10 Color Thermal Recording Material 11-13 Platen Roller 14-16 Thermal Head 17-19 Print Stage 20 Recording Material Supply Mechanism 28 System Controller 31 Positioning Mark 35-37 Conveying Section 38-40 Recording Section 41 Conveying Roller Pair 42 Auxiliary Roller Pair 43 Pulse motor 45 First position specifying unit 46 Second position specifying unit 54, 55, 60 Roller shift mechanism 71-73 Tip sensor 74-76 Mark sensor

Claims (4)

[Claims] 1. A thermal head for each color, a platen against which the thermal head is pressed, and a recording material transporting means for each color are arranged along a pass area of the recording material, and the thermal head for each color records the recording material. A color thermal printer for sequentially recording at least three-color images on a recording medium to record a full-color image, a tip sensor for detecting a tip of the recording material, and a mark sensor for detecting a positioning mark formed at a predetermined pitch on the recording material. A feed amount equivalent value detecting unit that detects a recording material feed amount equivalent value in the recording material conveying unit; a recording material form determining unit that determines whether the recording material is a long type or a cut sheet type; When the determination means determines that the type is the long type, the mark detection signal from the mark sensor and the feed amount equivalent value detection means A first position specifying unit that specifies a recording start position of the thermal head based on the feed amount equivalent value, and a leading edge detection signal from the leading edge sensor when the recording material form determining unit determines the cut sheet type. And a second position specifying unit for specifying the recording start position of the thermal head based on the feed amount equivalent value from the feed amount equivalent value detecting means. 2. The color thermal printer according to claim 1, wherein the recording material form determination means determines that the recording material is a long type when the positioning mark is detected by the mark sensor within a fixed time, A color thermal printer, wherein the recording material is determined to be a cut sheet type when a positioning mark is not detected within a fixed time after the leading edge sensor detects the leading edge. 3. The color thermal printer according to claim 1, wherein the recording material form determining means is composed of a recording material detection sensor which is attached to a recording material supply mechanism and detects each type of recording material. And a color thermal printer. 4. The color thermal printer according to claim 1, wherein the recording material form determination means comprises an input means for inputting a type of recording material.