JP3301865B2 - Color thermal printer - Google Patents

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 suitable for continuous printing, and more particularly, to wrapping two or three color thermal recording papers around an outer periphery of a platen drum and simultaneously using a plurality of thermal heads. The present invention relates to a color thermal printer for printing.

[0002]

2. Description of the Related Art As a color thermosensitive recording paper, as described in, for example, JP-A-3-288688, a cyan thermosensitive coloring layer, a magenta thermosensitive coloring layer, and a yellow thermosensitive coloring layer are sequentially formed on a support. Things are known. In this color thermosensitive recording paper, the lower the thermosensitive coloring layer, the higher the coloring energy, and each thermosensitive coloring layer has the property of being fixed by light with a specific electromagnetic ray.

When a full-color image is thermally recorded on the color thermosensitive recording paper, a thermal head in which a plurality of heating elements are arranged in a line is used, the thermal head is pressed against the color thermosensitive recording paper, and the yellow color developing energy is minimized. A yellow image is recorded line by line on the thermosensitive coloring layer. Next, the yellow thermosensitive coloring layer is fixed by irradiating ultraviolet rays having an emission peak in a wavelength range of approximately 420 nm, and then a magenta image is thermally recorded line by line on the magenta thermosensitive coloring layer with a thermal head. The magenta thermosensitive coloring layer is irradiated with ultraviolet rays having a light emission peak in a wavelength range of approximately 365 nm, and is light-fixed. Then, a cyan image is thermally recorded on the cyan thermosensitive coloring layer one line at a time by a thermal head. By these three thermal recordings, a full-color image is formed on the color thermosensitive recording paper.

[0004] In the recording system for thermal recording on the color thermosensitive recording paper, one thermal head is provided, and the platen drum around which one color thermosensitive recording paper is wound is rotated a plurality of times to sequentially thermally record each layer. A one-head method, three thermal heads are provided, and a platen drum around which one color thermal recording paper is wound is rotated once to thermally record each layer sequentially.
There is a pass method. The one-pass method requires three thermal heads as compared with the one-head method, so the structure is complicated, but there is an advantage that printing can be performed in a short time.

[0005]

A color thermal printer can be divided into a personal printer and a business printer according to the purpose of use. Personal use is mainly used when printing out images taken with an 8 mm video camera or still video camera. For personal use, a simple structure and low cost are required even if the printing speed is somewhat slow. On the other hand, for business use, high-speed printing is required even if the structure becomes complicated. Also, in business use, it is considered that there are many requests for postcards such as New Year's cards and greeting cards, but many of the same ones are printed with this postcard.

The above-described conventional one-pass type color thermal printer can print only one sheet by one rotation of the platen drum. Therefore, when printing the same one continuously like a post card, it takes a considerable time. Take it. Also, the three thermal heads have a predetermined time difference,
Since the recording papers are sequentially pressed against the color thermosensitive recording paper, the load on the platen drum fluctuates during printing. Due to this load change, the transport of the color thermosensitive recording paper is temporarily stopped, so that print unevenness due to multiple printing occurs.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a one-pass type color thermal printer capable of preventing load fluctuation of a platen drum during printing and performing continuous printing in a short time. It is.

[0008]

In order to achieve the above object, in the color thermal printer according to the first aspect, three color thermal recording papers have a diameter attachable to the outer peripheral surface, and one color thermal recording paper has one diameter in one direction. The platen drum is stopped at a predetermined time for paper supply and discharge every ３ rotation, and is disposed at substantially equal intervals along the outer peripheral surface of the platen drum, and is simultaneously driven while the platen drum rotates １ ／ rotation Then, three thermal heads for yellow image, magenta image, and cyan image for respectively recording a yellow image, a magenta image, and a cyan image on each color thermosensitive recording paper, and are disposed downstream of the thermal head for yellow image. , A yellow light fixing unit that irradiates electromagnetic radiation to a color thermosensitive recording paper on which a yellow image is recorded to optically fix a yellow thermosensitive coloring layer, and a downstream side of a magenta thermal head. Is location, the magenta fixer that the yellow image and a magenta image is optically fix the magenta coloring layer is irradiated with electromagnetic radiation in the recording paper that has been recorded,
The paper feed port located upstream of the thermal head for yellow, the paper exit port located downstream of the thermal head for cyan, and the clamper located at the paper feed / discharge position while the platen drum is stopped. To release the clamp at the end of the color thermal recording paper on which the full-color image is recorded during one rotation of the platen drum, and after the color thermal recording paper is discharged, it is fed through the paper feed port. When the tip of the new color thermal recording paper is inserted into the clamper, the clamper is moved between the clamper operating section and the paper feed port and the paper exit, and the color thermal recording paper from which the clamper has been released is removed. A paper discharge roller for feeding the paper from the rear end side to the paper discharge port is provided.

When the platen drum rotates by １ ／ in a predetermined direction, the first to third clampers are sequentially stopped at the sheet supply / discharge position for a predetermined time. During this stop, the color thermosensitive recording paper is fed from a paper feed port arranged upstream of the yellow thermal head. The leading end of the color thermosensitive recording paper is clamped by a clamper. During the rotation of the platen drum by 1/3, three thermal heads for yellow image, magenta image and cyan image are simultaneously driven, and the yellow image, magenta image and cyan image are respectively printed on each color thermosensitive recording paper. Record. When the color thermosensitive recording paper on which the yellow image is recorded passes through the yellow optical fixing device, the yellow thermosensitive coloring layer is optically fixed. Light fixing of the thermosensitive coloring layer is performed.

During one rotation of the clamper, a full-color image is recorded on the color thermosensitive recording paper. When the clamper is set at the recording position, the clamper is moved to the clamp release position by the clamper operating section to release the clamp. The clamped color thermal recording paper is sent to the paper discharge port from the rear end side by a paper discharge roller. After discharging the color thermal recording paper, the leading end of a new color thermal recording paper fed through the paper feed port is inserted into the clamper. In this way, one print is created for every 1/3 rotation of the platen drum.

In the color thermal printer according to the present invention,
Two clampers are attached to the platen drum, and two thermal heads are arranged on the outer periphery of the platen drum. The platen drum alternately repeats 1/2 rotation and 3/2 rotation. Therefore, one rotation is obtained by two rotations of the platen drum.
A print is created.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
The clampers 11 to 13 are provided at equal intervals on the outer peripheral surface of 0, and three color thermosensitive recording papers having a shorter overall length than each clamper interval can be wound. These clampers 11 to 13 are moved between the clamp position and the clamp release position by the clamper opening / closing mechanism 9 when the clamper is stopped at the paper supply / discharge position P as shown in FIG. At this clamp position, the front end of the color thermosensitive recording paper is pressed against the platen drum 10 by being biased by a spring. At the clamp release position, the clamper floats up from the platen drum 10 against the spring.

A thermal head 17 for a yellow image, a thermal head 18 for a magenta image, and a thermal head 19 for a cyan image are arranged on the outer periphery of the platen drum 10 at substantially equal intervals.

The rotating shaft 14 of the platen drum 10 is connected to a speed reducer 15 via, for example, a timing belt. The speed reducer 15 is constituted by gears and pulleys.
The rotation of the pulse motor 16 is reduced. Pulse motor 16
Rotates the platen drum 10 continuously or intermittently in the direction of the arrow, and stops when the paper supply / discharge ends when it rotates 排. During this stop, one of the three clampers is set at the paper supply / discharge position P, and is connected to the clamper opening / closing mechanism 9.

A fixing device 20 for fixing yellow is disposed between the thermal head 17 for yellow image and the thermal head 18 for magenta image. This fixing device 20
Are three ultraviolet lamps 23 having an emission peak of 420 nm.
And a reflector 24. A fixing device 25 for magenta fixing is disposed between the magenta image thermal head 18 and the cyan image thermal head 19.
The fixing device 25 includes three ultraviolet lamps 27 having an emission peak of 365 nm and a reflector 28. These ultraviolet lamps 23 and 27 are turned on when the platen drum 10 is rotating, and are turned off when the platen drum 10 is stopped.

A paper feed path 31 composed of guide plates 32 and 33 is provided upstream of the yellow image thermal head 17, and the paper feed port 31 a opens toward the paper supply / discharge position P. A transport roller pair 34 is disposed in the paper supply path 31. The nipped color thermal recording paper passes between the guide plates 32 and 33, and the leading end thereof is set at a paper supply / discharge position P. Inserted below the clamper.

A pair of guide plates 36, so that the discharge port 35a is located downstream of the cyan image thermal head 19,
A paper discharge path 35 composed of 37 is provided. Since the color thermosensitive recording paper itself has rigidity, its rear end is slightly warped. The warped rear end enters the paper discharge port 35a so as to be received by the guide plate 36 arranged stepwise.

A conveyance roller pair 41 is provided in the paper discharge passage 35, and nips the color thermosensitive recording paper fed into the conveyance passage 35 and discharges it to a tray. Transport roller pair 4
A fixing device 43 for bleaching is arranged beside 1 and irradiates the clamped portion with ultraviolet rays to remove bleaching without yellow. The fixing device 43 includes an ultraviolet lamp 44 and a reflector 4.
5, and the ultraviolet lamp 44 is turned on only when the sheet is discharged.

FIG. 4 shows an example of the layer structure of the color thermosensitive recording paper. The color thermosensitive recording paper 30 is provided on a support 50 with a cyan thermosensitive coloring layer 51 and a magenta thermosensitive coloring layer 5.
2, and a yellow thermosensitive coloring layer 53 are sequentially provided.
These thermosensitive coloring layers are arranged from the surface in the order of thermal recording, but the order can be changed.

The cyan thermosensitive coloring layer 51 has the lowest thermal sensitivity and develops cyan when high thermal energy is applied. The magenta thermosensitive coloring layer 52 has a medium heat sensitivity, and develops magenta color by heating. The magenta thermosensitive coloring layer 52 loses its coloring ability when irradiated with ultraviolet rays near 365 nm, and the recorded magenta image is fixed. The yellow thermosensitive coloring layer 53 has the highest thermal sensitivity and develops yellow by heating. The yellow thermosensitive coloring layer 53 loses its coloring ability when irradiated with ultraviolet light having a wavelength of around 420 nm, so that the recorded yellow image is fixed.

Next, the operation of the above embodiment will be described. When continuous printing is instructed to print many sheets of the same material like a post card, as shown in FIG. 2, the color thermosensitive recording paper 30a is nipped by the conveying roller pair 34 and passes through the paper feeding path 31. Is sent out from the paper feed port 31a. In this state, the clamper 11 is set at the paper supply / discharge position P, and is pushed up by the clamper opening / closing mechanism 9 to the clamp release position against the spring. Therefore, the leading end of the color thermal recording paper 30a sent out from the paper feed port 31a is
And the clamper 11. When it is detected by the photo sensor or the like that the recording paper is inserted below the clamper 11, the rotation of the transport roller 34 is first stopped, and the transport of the color thermosensitive recording paper 30a is stopped. Next, the clamper opening / closing mechanism 9 operates to release the clamper 11. This clamper 11 is moved to a clamp position by a spring,
The leading end of the color thermosensitive recording paper 30a is clamped.

After clamping the color thermosensitive recording paper 30a,
The pulse motor 16 rotates. The rotation of the pulse motor 16 is transmitted to the platen drum 10 via the speed reducer 15. The platen drum 10 rotates while pulling out and winding the color thermosensitive recording paper 30a from the paper feed passage 31. At this time, the transport roller pair 34 is free to rotate by the friction clutch or separated from each other by the shift mechanism so as not to pull the color thermosensitive recording paper 30a. The ultraviolet lamps 23 and 27 are turned on when the rotation of the platen drum 10 starts.

When the clamper 11 passes through the yellow image thermal head 17 while the platen drum 10 is rotating, the yellow image thermal head 17 rotates and presses the color thermosensitive recording paper 30a. When the yellow image thermal head 17 is driven according to the yellow image data, the yellow image is thermally recorded line by line on the yellow thermosensitive coloring layer 53 of the color thermosensitive recording paper 30a.
When the portion on which the yellow image is thermally recorded comes below the fixing device 20, the yellow thermosensitive coloring layer 53 is optically fixed by irradiation of 420 nm ultraviolet rays so that the yellow thermosensitive coloring layer 53 is not colored. When the color thermosensitive recording paper 30a passes through the yellow image thermal head 13, the thermal head 17 moves to a retracted position away from the platen drum 10.

When the platen drum 10 rotates one third,
When the clamper 12 reaches the sheet supply / discharge position P, the pulse motor 1
6 stops. Thus, the rotation of the platen drum 10 is stopped, and the ultraviolet lamps 23 and 27 are turned off.
During this stop, the color thermosensitive recording paper 30b is nipped by the pair of transport rollers 34 and passes between the guide plates 32 and 33 toward the clamper 12. When the color thermosensitive recording paper 30b is clamped by the clamper 12, the pulse motor 16 rotates again. 1/3 rotation of the platen drum 10 starts,
At the same time, the ultraviolet lamps 23 and 27 are turned on.

While the platen drum 10 is rotating, the clamper 1
When 1 passes through the magenta image thermal head 18,
The magenta image thermal head 18 rotates to press the color thermosensitive recording paper 30a. The magenta image thermal head 18 thermally records a magenta image line by line on the magenta thermosensitive coloring layer 52. When the portion on which the magenta image is thermally recorded comes below the fixing device 25, the magenta thermosensitive coloring layer 52 is optically fixed by irradiation with ultraviolet rays of 365 nm so as not to develop color. The magenta image thermal head 18 moves to the retreat position after recording the magenta image.

On the other hand, at the same time as the clamper 11 passes through the magenta image thermal head 18, the clamper 12 passes through the yellow image thermal head 17. The thermal head 17 for yellow image rotates and presses the color thermosensitive recording paper 30b. The yellow image thermal head 17 thermally records the yellow image line by line on the color thermosensitive recording paper 30b. When the portion on which the yellow image is thermally recorded comes under the fixing device 20, it is irradiated with ultraviolet rays of 420 nm and is optically fixed. The platen drum 10 stops after one third rotation. As described above, the fed new color thermal recording paper 30c is clamped by the clamper 13.

When the platen drum 10 rotates again 1/3, the yellow image thermal head 1 as shown in FIG.
7, a yellow image is recorded on the color thermosensitive recording paper 30c, and a magenta image is recorded on the color thermosensitive recording paper 30b by the magenta image thermal head 18. Further, the cyan image thermal head 19 is a color thermosensitive recording paper 30a.
To record a cyan image. As described above, since the three thermal heads 17 to 19 are simultaneously driven, the platen drum 10 does not fluctuate in load during printing, so that the platen drum 10 stably rotates.

When the platen drum 10 stops after rotating one third of a time, as shown in FIG. 3, a delivery roller 40 is attached to the color thermosensitive recording paper 30a on which a full-color image is recorded.
Shifts into pressure. Also, at this time, the rear end of the color thermosensitive recording paper 30a has
a, and hits the guide plate 36.

Further, since the clamper 11 is set at the paper supply / discharge position P, when the clamper opening / closing mechanism 9 operates,
Hook the clamper 11 and move it to the clamp release position,
The clamp of the color thermal recording paper 30a is released.

When the feed roller 40 rotates, the color thermosensitive recording paper 30a is fed into the paper discharge path 35 with the rear end at the top. The color thermosensitive recording paper 30a is nipped by a pair of transport rollers 41 in a paper discharge path 35 and discharged toward a tray. During this paper ejection, ultraviolet rays of 365 nm are irradiated by the ultraviolet lamp 44 of the fixing device 43, and the portion pressed by the clamper 11 is bleached to remove the yellow tint.

After the color thermosensitive recording paper 30a is discharged, a new color thermosensitive recording paper 30d is fed through the paper feed path 31, and the leading end is inserted under the clamper 11.

As described above, after the sheet is fed, the platen drum 10 rotates 1/3 turn, and the thermal recording is started again. Then, the paper is discharged and fed every １ ／ rotation. Thus, the color thermosensitive recording paper on which the full-color image is recorded is sent out to the tray every 1/3 rotation of the platen drum 10.

The embodiment shown in FIG. 5 has two platen drums.
One clamper is provided, and the same members as those shown in FIG. 1 are denoted by the same reference numerals. Platen drum 10
Are provided on the outer periphery of the
A sheet of color thermal recording paper can be wound. The platen drum 10 alternately rotates １ ／ and ／ in a fixed direction.

On the outer periphery of the platen drum 10, thermal heads 77 and 78 are provided so as to face each other. The thermal head 77 heats a plurality of heating elements according to the yellow image data or the cyan image data to perform thermal recording of one of a yellow image and a cyan image. The thermal head 78 heat-generates a plurality of heating elements according to the magenta image data to perform thermal recording of the magenta image.

Downstream of the thermal head 77, a fixing device 80 for yellow is provided. This fixing device 80
It comprises a book ultraviolet lamp 83 and a reflector 84.
A fixing device 85 for magenta is provided downstream of the thermal head 78.
Is arranged. The fixing device 85 includes two ultraviolet lamps 87 and a reflector 88. These fixing devices 8
0 and 85 are lit while the platen drum 10 is rotating and off when the platen drum 10 is stopped.

The procedure of continuous printing in this color thermal printer will be briefly described. While the platen drum 10 is stopped, the color thermosensitive recording paper 1 sent from the paper feed path 31
00 is inserted into the clamper 71 set at the sheet supply / discharge position. When the clamper 71 nips the leading end of the color thermosensitive recording paper 100, the platen drum 10 rotates by 回 転. During this rotation, a yellow image is recorded by the thermal head 77, and the yellow heat-sensitive fixing layer is fixed by the fixing device 83.

When the platen drum 10 stops after rotating by １ ／, a new color thermosensitive recording paper 101 is inserted into the clamper 72 at the paper supply / discharge position.

After clamping by the clamper 72, the platen drum 10 continuously rotates 3/2. First half
During the rotation, the color thermal recording paper 100 is
After the magenta image is recorded at 8, the magenta thermosensitive coloring layer is fixed by the fixing device 87. On the other hand, a yellow image is recorded on the color thermosensitive recording paper 101 by the thermal head 77, and then the yellow thermosensitive coloring layer is fixed by the fixing device 80.

Subsequently, while the platen drum 10 makes a half rotation, the color thermosensitive recording paper 100 is
At 7, a cyan image is recorded. At the same time, the recording and fixing of the magenta image on the color thermosensitive recording paper 101 are performed by the thermal head 78 and the fixing device 85.

When the platen drum 10 further rotates by half, the color thermal recording paper 100 passes through the thermal head 78, and the clamper 71 reaches the paper supply / discharge position. On the other hand,
A cyan image is recorded on the color thermal recording paper 101 by the thermal head 77.

As previously described, the platen drum 10 has three
/ 2 rotations, the clamper 71, as shown in FIG.
It is set at the paper supply / discharge position. When the discharge roller 40 is rotated after the clamper 71 is moved to the clamp release position, the color thermal recording paper 10 on which the full-color image is recorded is moved.
0 is sent to the paper discharge path 35. After the discharge, the new color thermal recording paper 102 is clamped by the clamper 71.

The platen drum 10 stops by １ ／ rotation. During this time, the yellow image is recorded on the color thermosensitive recording paper 102 and the yellow thermosensitive coloring layer is fixed. On the other hand,
The color thermal recording paper 101 passes directly through the thermal head 78. As described above, the clamp of the clamper 72 is released, and the color thermal recording paper 101 is discharged by the discharge roller 80.
Is discharged. Hereinafter, printing is performed by alternately repeating 3/2 rotation and 1/2 rotation, and one print is discharged by two rotations of the platen drum 10.

[0043]

As described above in detail, according to the color thermal printer according to the first aspect, three clampers are provided on the platen drum, and three color thermal recording papers are wound at the same time. Since the thermal heads are arranged at equal intervals and images are simultaneously recorded on each color thermal recording paper, continuous printing can be performed at high speed. Further, since the three thermal heads are simultaneously driven while being pressed against the three color thermosensitive recording papers, the load does not fluctuate during printing as in the related art. Therefore, it is possible to prevent the occurrence of print unevenness due to multiple printing of the same line.

Further, the color thermal printer according to the second aspect is provided with two clampers and two thermal heads, so that the printing speed is lower than that of the first aspect, but it is faster than the conventional one. Can print. Further, the occurrence of print unevenness can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a thermal recording state of a color thermal printer of the present invention.

FIG. 2 is a schematic diagram showing a paper feed state of color thermal recording paper.

FIG. 3 is a schematic diagram illustrating a discharge state of a color thermosensitive recording sheet.

FIG. 4 is an explanatory diagram showing a layer structure of a color thermosensitive recording paper.

FIG. 5 is an explanatory diagram showing another embodiment of the color thermal printer.

[Explanation of symbols]

 11 to 13 clamper 10 platen drum 17 to 19 thermal head 20, 25, 43 fixing unit 30, 30a to 30d color thermal recording paper 71, 72 clamper 77, 78 thermal head 100 to 102 color thermal recording paper

Continuation of front page (56) References JP-A-4-267160 (JP, A) JP-A-5-16400 (JP, A) JP-A-5-254201 (JP, A) JP-A-6-143630 (JP) JP-A-5-124236 (JP, A) JP-A-5-212885 (JP, A) JP-A-62-48578 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB Name) B41J 2/325 B41M 5/26

Claims (2)

(57) [Claims] 1. A thermosensitive coloring layer of cyan, a thermosensitive coloring layer of magenta and a thermosensitive coloring layer of yellow are sequentially provided on a support, and a thermosensitive coloring layer at the top and a thermosensitive coloring layer at the middle are different. A color thermosensitive printer that records light on a full-color image using color thermosensitive recording paper that has the property of fixing light with electromagnetic radiation in the wavelength range, and that has lower color developing heat energy as the lower layer, A platen drum that has a diameter that allows the color thermosensitive recording paper to be mounted on the outer peripheral surface, and stops for a predetermined time for feeding and discharging each time it rotates 1/3 in one direction; Three clampers are provided at intervals and clamp the leading ends of three color thermal recording papers, respectively, and are arranged at approximately equal intervals along the outer peripheral surface of the platen drum, and the platen drum rotates 1/3 turn And a thermal head for yellow image, magenta image, and cyan image, which are simultaneously driven to record a yellow image, a magenta image, and a cyan image on each color thermosensitive recording paper, respectively, and a thermal head for yellow image A yellow light fixing unit that irradiates electromagnetic radiation to the color thermosensitive recording paper on which the yellow image is recorded to optically fix the yellow thermosensitive coloring layer, and is disposed downstream of the magenta thermal head, A magenta fixing device for optically fixing the magenta thermosensitive coloring layer by irradiating electromagnetic radiation to a color thermosensitive recording paper on which a yellow image and a magenta image are recorded; and a paper feed port arranged upstream of the yellow thermal head. When the platen drum is stopped, the paper discharge port located downstream of the cyan thermal head Move to the release position, release the clamp on the end of the color thermal recording paper on which the full-color image is recorded during one rotation of the platen drum, and feed the paper through the paper feed port after discharging the color thermal recording paper When the tip of the new color thermal recording paper is inserted into the clamper, the clamper is moved between the clamper and the paper feed port and the paper exit, and the color thermal recording with the clamper released A color thermal printer comprising a paper discharge roller for feeding paper from a rear end side to a paper discharge port. 2. A thermosensitive coloring layer of cyan, a thermosensitive coloring layer of magenta, and a thermosensitive coloring layer of yellow are sequentially provided on a support, and a thermosensitive coloring layer at the top and a thermosensitive coloring layer at the middle are different. A color thermal printer that records light on a full-color image using color thermal recording paper that has the property of fixing light by electromagnetic radiation in the wavelength range and that the lower layer has higher color development thermal energy. Color thermosensitive recording paper has a diameter that can be mounted on the outer peripheral surface, and rotates in one direction by alternately repeating 1/2 rotation and 3/2 rotation, and after each rotation, only for a predetermined time for paper feeding and discharging. A platen drum to be stopped; two clampers provided at equal intervals on the outer peripheral surface of the platen drum to clamp the leading ends of two color thermosensitive recording papers; and opposing each other along the outer peripheral surface of the platen drum And first and second thermal heads, which are simultaneously driven and record one of a yellow image, a magenta image, and a cyan image on each color thermosensitive recording paper, while the platen drum is substantially rotated by half, and An optical fixing unit for yellow, which is disposed downstream of the first thermal head and irradiates electromagnetic radiation to a color thermosensitive recording paper on which a yellow image is recorded by the thermal head to optically fix the yellow thermosensitive coloring layer; A magenta optical fixing device that is disposed downstream of the second thermal head and irradiates electromagnetic radiation to the color thermosensitive recording paper on which the magenta image is recorded with the thermal head to optically fix the magenta thermosensitive coloring layer; A paper feed port disposed upstream of the first thermal head, a paper discharge port disposed downstream of the second thermal head, and a paper supply / discharge position while the platen drum is stopped. Move the clamper to the clamp release position, release the clamp on the leading end of the color thermal recording paper on which the full-color image is recorded during the two rotations of the platen drum, and pass the paper through the paper feed port after discharging the thermal recording paper. When the tip of a new color thermal recording paper fed into the clamper is inserted into the clamper, it is placed between the clamper operating section that moves to the clamp position and the paper feed port and the paper discharge port, and the clamp is released. A color thermal printer comprising a paper discharge roller for feeding a color thermal recording paper from a rear end side to a paper discharge port.