JP2889771B2 - 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 for thermally recording a video image or the like on a color thermal recording material.

[0002]

2. Description of the Related Art In a color thermal printer, for example, as described in Japanese Patent Application Laid-Open No. 61-213169,
A color thermosensitive recording material is used in which a magenta thermosensitive coloring layer, a cyan thermosensitive coloring layer, and a yellow thermosensitive coloring layer are sequentially formed on a support so that a full-color image can be directly thermally recorded. Then, heat recording is performed in order from the heat-sensitive coloring layer on the surface, and when performing heat recording on the next heat-sensitive coloring layer, in order to prevent the heat-recorded heat-sensitive coloring layer thereabove from being heat-recorded again, after the heat recording, Each of the heat-sensitive coloring layers is fixed by light irradiation by irradiating electromagnetic rays in a wavelength range peculiar to the heat-sensitive coloring layer. As shown in FIG. 10A, the heat recording and the light fixing are generally performed by fixing the front end of the color thermosensitive recording material 2 to the outer peripheral surface of the platen drum 1 with the clamp portion 3 and moving the platen drum 1 in the direction of the arrow. The rotation is performed by the thermal head 4 and the yellow and magenta light fixing lamps 5 and 6 arranged along the peripheral surface of the platen drum 1 while rotating. In the drawing, reference numeral 7 denotes a paper feed passage, and 8 denotes a paper discharge passage.

That is, after a yellow image is thermally recorded on the uppermost yellow thermosensitive recording layer by a thermal head 4, the yellow image is optically fixed by a yellow light fixing lamp 5.
Next, after the magenta image is thermally recorded on the magenta heat-sensitive recording layer by the thermal head 4, it is optically fixed by the magenta light fixing lamp 6, and then the cyan image is thermally recorded on the cyan heat-sensitive recording layer by the thermal head 4. After that, the clamped portion of the color thermosensitive recording material 2 is discharged while being bleached by the light fixing lamp 6 for magenta.

[0004]

However, FIG.
As shown in (B), simply arranging the thermal head 4 and the optical fixing lamps 5 and 6 results in C> (360 ° −α).
+ (Β-A), and when the magenta image is thermally recorded after the yellow light fixing and light fixing is performed, the yellow light fixing lamp 5 and the magenta light fixing lamp 6 need to be simultaneously turned on. Therefore, an inverter is required for each lamp, and the device configuration is complicated. Each symbol in the figure represents A: the effective irradiation range of the magenta light fixing lamp, B: the effective irradiation range of the yellow light fixing lamp,
C: recording area, α: distance from the recording position to the end of the effective irradiation range of the yellow light fixing lamp, and β: distance from the recording position to the end of the effective irradiation range of the magenta light fixing lamp.

[0005] In the arrangement shown in FIG.
When each lamp is individually lit using one inverter, the platen drum 1 must be rotated each time each lamp is lit, and the platen drum 1 must be turned one extra turn instead of being lit simultaneously. . For this reason, there is a problem that the printing time becomes long.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to provide a color thermal printer capable of efficiently performing color thermal recording using one inverter.

[0007]

According to a first aspect of the present invention, there is provided a color thermal printer, comprising: a thermal head, a first light fixing lamp, and a second light fixing lamp; Since the thermal head, the first optical fixing lamp, and the second optical fixing lamp are arranged in this order, color thermal recording can be performed efficiently using one inverter.

According to a second aspect of the present invention, there is provided a color thermal printer, comprising: a thermal head, a first light fixing lamp, and a second light fixing lamp; , The first light fixing lamp, and the center of the platen drum from the rear end of the effective irradiation range of the first light fixing lamp to the effective irradiation range of the second light fixing lamp in the rotation direction of the platen drum. It is arranged so that the angle is equal to or larger than the angle of the print screen with respect to the center of the platen drum.

According to a third aspect of the present invention, there is provided a color thermal printer according to the first and second aspects, wherein a tip of an effective irradiation range of an optical fixing lamp disposed next to the thermal head is set to the thermal head. Is positioned immediately after.

According to a fourth aspect of the present invention, there is provided the color thermal printer according to the first, second, and third aspects, wherein the discharge port of the color thermal recording material is provided by the second optical fixing lamp. Since the clamp is released immediately after the rear end of the irradiation range, the clamp can be released after thermal recording of the last layer, and the first light fixing lamp can be used to bleach the clamped portion. And printing time can be shortened.

[0011]

Referring to FIG. 1, a plurality of sheet-like color thermosensitive recording materials 10 are stacked in a cassette 11 and the uppermost one is extruded by a paper feed roller 12 to form a paper feed passage 13. Sent to This paper feed path 13
Is provided with a pair of transport rollers 14, and the cassette 11
Is fed toward the platen drum 15. This platen drum 15
Is driven to rotate by a stepping motor 17 via a platen shaft 16.

The platen drum 15 is provided with a clamp 18 for pressing and fixing the front end 10a of the color thermosensitive recording material 10 to the outer peripheral surface 15a of the platen drum 15. The clamp portion 18 is attached to the platen shaft 16 via a long hole 18a. A solenoid 19 is fixed to a side surface 18 b of the clamp portion 18, and an annular portion 20 of the plunger is fitted on the platen shaft 16. As is well known, a spring is built in the solenoid 19 and urges the ring-shaped portion 20 in a direction to draw it toward the solenoid 19. Therefore, when the solenoid 19 is not energized, the clamp portion 18 is constantly urged in a direction for fixing the front end portion 10a of the color thermosensitive recording material 10. At this time, as shown in FIG. 2, the claws 18 c of the clamp portion 18 enter the grooves 15 b formed on the outer peripheral surface 15 a of the platen drum 15.

The voltage applied to the solenoid 19 is controlled in two stages, and the clamp unit 18 is moved in two stages, a sheet feeding position and a sheet discharging position, according to the applied voltage. At the paper feed position,
As shown in FIG.
Although 0a is not fixed, the claw 18c of the clamp portion 18 does not completely come out of the groove 15b, and the tip portion 10a abuts on the claw 18c to prevent the color thermosensitive recording material 10 from passing through. Further, as shown in FIG. 4, at the sheet discharging position, the tip of the claw 18c and the outer peripheral surface 1 of the platen drum 15 are moved.
5a, and the color thermosensitive recording material 10
Can pass through the clamp portion 18, thereby enabling forward rotation discharge.

On the outer periphery of the platen drum 15, a thermal head 2 is located at a thermal recording position of the color thermosensitive recording material 10.
1, a magenta light fixing device 22 is disposed at a position downstream of the thermal head 21 and close to the thermal head 21, and a yellow light fixing lamp 23 is disposed further downstream thereof. Thermal head 2
Reference numeral 1 denotes a configuration in which a large number of heating elements are arranged in a line in the main scanning direction, and each heating element generates heat energy according to the density of a pixel.

The light fixing lamp 22 for magenta comprises an ultraviolet lamp 24 having an emission peak of about 365 nm. As shown in FIG. 5, a fluorescent layer 24b and a reflective layer 24c are formed on the inner peripheral surface of a glass tube 24a. It has been applied.
The reflection layer 24c is not formed on a part of the peripheral surface of the glass tube 24a, and the unformed portion 24d is linear in the tube direction of the glass tube. Ultraviolet rays having an emission peak of approximately 365 nm are irradiated from the non-formed portion 24d. In addition,
Although not shown, instead of the ultraviolet lamp having the reflection layer 24c, a reflection layer may be provided outside the glass tube. In this case, in addition to forming the reflective layer in a layered shape on the outer peripheral surface of the glass tube, a reflective tube having a part of the peripheral surface cut out may be fitted to the glass tube. Furthermore,
The layer positions of the reflective layer 24c and the fluorescent layer 24b may be interchanged, and in this case, the non-formed portion 24d is provided in the reflective layer 24c. The yellow light fixing lamp 23 is constituted by a rod-shaped ultraviolet lamp 26 having an emission peak of approximately 420 nm in a rod shape, and is configured similarly to the magenta ultraviolet lamp 24 except that the composition of the fluorescent layer is different.

A stopper 28 is provided between the thermal head 21 and the magenta light fixing lamp 22 at a position close to the magenta light fixing lamp 22. The stopper 28 prevents the clamp unit 18 from rotating together with the platen drum 15 after the clamp unit 18 is moved to the paper discharge position (see FIG. 4) in order to release the fixing of the color thermosensitive recording material 10. The rotation of the clamp 18 is prevented.

Between the magenta light fixing lamp 22 and the yellow light fixing lamp 23, there is provided a paper discharge passage 30 for discharging the color thermosensitive recording material 10 on which all the heat recording has been completed. A transport roller pair 32 for holding the thermal recording material 10 and transporting it toward a paper output tray 31 (see FIG. 1) is provided.

FIG. 6 shows an example of a color thermosensitive recording material. On the support 41, the cyan thermosensitive coloring layer 4
2, magenta thermosensitive coloring layer 43, yellow thermosensitive coloring layer 4
4, protective layers 45 are sequentially provided. Each of the thermosensitive coloring layers 42 to 44 is provided from the surface in the order of thermal recording. For example, when thermal recording is performed in the order of magenta, yellow, and cyan, a yellow thermosensitive coloring layer and a magenta thermosensitive coloring are provided. The positions of the layers are interchanged. Since the deeper the heat-sensitive coloring layers 42 to 44, the higher the coloring heat energy, the three-color heat-sensitive coloring layers 42 to 44 can be selectively recorded by changing the coloring heat energy.

When the magenta thermosensitive coloring layer 43 is irradiated with ultraviolet rays near 365 nm after thermal recording with the thermal head 21, the diazonium salt compound is photolyzed and loses its coloring ability. When the yellow thermosensitive coloring layer 44 is irradiated with near-ultraviolet rays near 420 nm, it is light-fixed and loses its coloring ability. For this reason, light is fixed even by near-ultraviolet rays of 365 nm having higher energy. Since the magenta thermosensitive coloring layer 43 and the yellow thermosensitive coloring layer 44 contain a diazonium salt compound, the color thermosensitive recording material 10 originally has a light yellow color.

When the thermosensitive coloring layers 43 and 44 are sufficiently fixed by light, the unrecorded portion of the color thermosensitive recording material 10 changes from light yellow to transparent. However, since the front end portion 10a of the color thermosensitive recording material 10 is covered with the clamp portion 18 and shielded from light, this portion is not bleached and remains in a light yellow band shape. Therefore, in order to bleach the clamp portion and shorten the printing time, in the present embodiment, when the color thermosensitive recording material 10 is discharged to the discharge tray 31,
As shown in FIG. 4, bleaching of the clamped portion is performed by the light fixing lamp 22 for magenta. As a result, the distal end portion 10a, which has been shielded by the clamp portion 18, is also irradiated with ultraviolet rays, so that the yellow band in the unfixed state is completely bleached.

FIG. 7 shows the characteristics of each of the thermosensitive coloring layers 42 to 44. The thermal energy on the horizontal axis represents the thermal energy generated by the heating element of the thermal head 21. The thermal energy of the yellow thermosensitive coloring layer 44 is the lowest, and the thermal energy of the cyan thermosensitive coloring layer 42 is the highest.
The main cause of this difference in thermal energy is that the cyan thermosensitive coloring layer 42 must be heated via the yellow thermosensitive coloring layer 44 and the magenta thermosensitive coloring layer 43.
As described above, since the heat energy required for the thermosensitive coloring layer 42 to generate the thermosensitive color is approximately 80 mJ / mm ² or more, the cyan thermosensitive coloring layer 42 does not develop a color in a normal storage state.

Next, the operation of the above embodiment will be described with reference to the sequence shown in FIG. At the time of sheet feeding, the platen drum 10 is stopped at the set position shown in FIG. At this time, the solenoid 19 is energized, and the clamp unit 18 is moved to the sheet feeding position. The transport roller pair 14 holds the color thermosensitive recording material 10 supplied from the cassette 11 by the paper feed roller 12 and transports it toward the platen drum 15. At the same time when the leading end portion 10a of the color thermosensitive recording material 10 comes into contact with the claw 18c of the clamp portion 18, the transport roller pair 14 is temporarily stopped, and the energization of the solenoid 19 is stopped. As a result, the clamp portion 18 is pulled back by the built-in spring, so that the distal end portion 10a is clamped by the clamp portion 18. After this clamping, the stepping motor 17 is driven to rotate the platen drum 15 and the conveying roller pair 14, so that the color thermosensitive recording material 10 is wound around the outer peripheral surface 15 a of the platen drum 15.

When the platen drum 15 rotates, the leading end of the recording area of the color thermosensitive recording material 10 is
When the number reaches 1, the yellow image is thermally recorded line by line by the thermal head 21. In the thermal recording of this yellow image, each heating element of the thermal head 21
Heat is generated at a temperature in consideration of the coloring characteristics shown in FIG. The portion where the yellow image has been thermally recorded reaches the yellow light fixing lamp 23 as shown in FIG. 2, where the light fixing is performed. The near-ultraviolet light of approximately 420 nm is emitted from the color thermosensitive recording material 10 by the yellow light fixing lamp 23.
At the time of the next thermal recording of the magenta thermosensitive coloring layer 44, so that yellow is not developed.

When the rotation of the platen drum 15 advances and the recording area reaches the position of the thermal head 21 again, FIG.
As shown in the figure, the magenta image is
Is thermally recorded one line at a time. When a magenta image is thermally recorded and the recording screen covers the effective irradiation range of the light fixing lamp 22 for magenta, the thermal head is moved so that the rear end of the recording screen passes through the effective irradiation range of the light fixing lamp 23 for yellow. Since the lamp 21 and the lamps 22 and 23 are disposed, the yellow light fixing lamp 23 is turned off and the magenta light fixing lamp 22 is turned on until the rear end of the color thermosensitive recording material 10 passes. As a result, ultraviolet light having a wavelength of about 365 nm is irradiated on the color thermosensitive recording material 10, and when the cyan thermosensitive coloring layer 42 is thermally recorded,
Light is fixed to the extent that magenta does not develop color.

Next, when the color thermosensitive recording material 10 faces the thermal head 21, recording of a cyan image is started. Immediately before the recording of the cyan image, the solenoid 19 is energized, and as shown in FIG. 4, the clamp portion 18 is moved to the paper discharge position, and the clamp of the leading end 10a is released. Then, the clamp portion 18 abuts against the stopper 28, and the rotation thereof is stopped at that position. However, since the platen drum 15 is continuously rotated by the stepping motor 17, the transport roller (not shown) which is in rolling contact with the platen drum 15 ), The color thermosensitive recording material 10 is
8 and is conveyed toward the paper discharge path 30. At the time of this paper ejection, the cyan image is formed by the thermal head 21 on the cyan thermosensitive coloring layer 42 of the color thermosensitive recording material 10.
Is thermally recorded one line at a time. Then, the color thermosensitive recording material 10 is held by the pair of conveying rollers 32 through the paper discharge path 30 and discharged to the paper discharge tray 31 (see FIG. 1).

As shown in FIG. 4, at the start of the discharge, the light fixing lamp 22 for magenta is turned on, whereby the front end portion 1 covered with the clamp portion 18 and having a yellow band is formed.
Oa is irradiated with ultraviolet rays and bleached. As described above, the bleaching of the clamped portion is performed at the time of paper discharge, so that the time required for the bleaching is included in the paper discharge time, so that the printing time can be reduced as compared with the case where the bleaching is performed separately.

In each of the above embodiments, the paper discharge path 30 is provided between the magenta light fixing lamp 22 and the yellow light fixing lamp 23. In addition, as shown in FIG. Alternatively, the paper discharge passage 50 may be provided after the yellow light fixing lamp 23. In this embodiment, except that the positions of the paper discharge path 50 and the yellow light fixing lamp 23 are exchanged,
The configuration is the same as that of the above embodiment, and the same components are denoted by the same reference numerals.

In FIG. 9B, C ≦ (360 ° −
α) + (β−A), and the light fixing lamp 22 for magenta
And the yellow light fixing lamp 23 can be turned on alternately.
Therefore, also in this embodiment, one inverter can be used. Further, as shown in FIG. 9C, even if the positions of the magenta light fixing lamp 22 and the yellow light fixing lamp 23 are interchanged, C ≦ (360 ° −α) + (β−A) holds. The light fixing lamp 22 and the yellow light fixing lamp 23 can be turned on alternately.

Although the above embodiment is a line printer for printing by moving a thermal head or a color thermosensitive recording material relatively in the sub-scanning direction, the present invention is applicable to a serial printer for printing by moving two-dimensionally relative to each other. Can also be applied. This serial printer uses a thermal head in which heating elements are arranged in the main scanning direction, moves in the sub-scanning direction during thermal recording, and the color thermosensitive recording material moves in the main scanning direction.

[0030]

As described above, according to the first aspect of the present invention,
According to the color thermal printer described above, the thermal head, the first light fixing lamp, and the second light fixing lamp are arranged in this order in the rotation direction of the platen drum.
The simultaneous lighting of the optical fixing lamps required in the arrangement shown in FIG. Thereby, each fixing lamp can be turned on by one inverter, and the apparatus configuration can be simplified.

According to the color thermal printer of the present invention, the thermal head, the second light fixing lamp, and the first light fixing lamp are arranged in this order in the rotation direction of the platen drum, and the first light is fixed. Since the angle from the rear end of the effective irradiation range of the fixing lamp to the effective irradiation range of the second optical fixing lamp with respect to the center of the platen drum is set to be equal to or larger than the angle with respect to the center of the platen drum on the print screen, two pieces are arranged. It is not necessary to turn on the light fixing lamps at the same time, and each fixing lamp can be turned on by one inverter, and the configuration of the apparatus can be simplified.

Moreover, since the lamps are arranged as close to the thermal head as possible, the end time of the optical fixing after the thermal recording can be shortened by an amount corresponding to the approach of the lamps to the thermal head, thereby further shortening the printing time. can do. That is, since the rotation speed of the platen drum at the time of fixing by each fixing lamp is slower than the idle feeding speed after the end of the fixing, the idle feeding timing can be advanced by an amount corresponding to the earlier fixing end, and as a result, the printing time can be shortened. Can be shortened.

Further, by providing a discharge port for the color thermosensitive recording material having undergone thermal recording between the first light fixing lamp and the second light fixing lamp, the clamp portion is bleached by the first light fixing lamp. Since the paper can be discharged while the discharge distance can be shortened, the printing time can be further reduced.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a state in which a color thermal recording material is fed in a color thermal printer of the present invention.

FIG. 2 is a schematic diagram showing a state in which thermal recording and optical fixing are performed on a yellow thermosensitive coloring layer of a color thermosensitive recording material.

FIG. 3 is a schematic view showing a state in which thermal recording and optical fixing are performed on a magenta thermosensitive coloring layer of a color thermosensitive recording material.

FIG. 4 is a schematic view showing a state in which a cyan thermosensitive coloring layer of a color thermosensitive recording material is thermally recorded and then discharged.

FIG. 5 is a sectional view showing an ultraviolet lamp.

FIG. 6 is an explanatory diagram showing a layer structure of a color thermosensitive recording material.

FIG. 7 is a graph showing the color development characteristics of a color thermosensitive recording material.

FIG. 8 is a flowchart showing a sequence of the color thermal printer.

FIG. 9 is a schematic diagram (A) and explanatory diagrams (B) and (C) showing an arrangement of a thermal head and a light fixing lamp of another color thermal printer of the present invention.

FIG. 10 is a schematic diagram (A) and an explanatory diagram (B) showing an example of an arrangement of a thermal head and an optical fixing lamp of a conventional color thermal printer.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 color thermosensitive recording material 15 platen drum 18 clamp section 21 thermal head 22 light fixing lamp for magenta 23 light fixing lamp for yellow 24 ultraviolet lamp 30, 50 paper discharge passage

Claims (4)

(57) [Claims] 1. A color thermosensitive recording material in which a plurality of thermosensitive coloring layers are laminated, between a fixed position for fixing an end portion of the color thermosensitive recording material to an outer peripheral surface of a platen drum and a retracted position for releasing the fixing. And a driving unit for rotating and driving the platen drum, a thermal head for thermally recording on the color thermal recording material fixed to the platen drum, and a light-sensitive color thermal recording material thermally recorded by the thermal head. A first and a second light fixing lamps for fixing, the recording of each heat-sensitive coloring layer is performed while rotating the platen drum in the same direction, and the first and second lamps are used for light fixing in order. In the thermal printer, the thermal head, the first light fixing lamp, and the second light fixing lamp are moved in the direction of rotation of the platen drum.
A color thermal printer in which a first light fixing lamp and a second light fixing lamp are arranged in this order. 2. A color thermosensitive recording material in which a plurality of thermosensitive coloring layers are laminated, between a fixed position for fixing the end of the color thermosensitive recording material to the outer peripheral surface of the platen drum and a retracted position for releasing the fixing. And a driving unit for rotating and driving the platen drum, a thermal head for thermally recording on the color thermal recording material fixed to the platen drum, and a light-sensitive color thermal recording material thermally recorded by the thermal head. A first and a second light fixing lamps for fixing, the recording of each heat-sensitive coloring layer is performed while rotating the platen drum in the same direction, and the first and second lamps are used for light fixing in order. In the thermal printer, the thermal head, the first light fixing lamp, and the second light fixing lamp are moved in the direction of rotation of the platen drum.
The second light fixing lamp and the first light fixing lamp are arranged in this order, and from the rear end of the effective irradiation range of the first light fixing lamp to the effective irradiation range of the second light fixing lamp in the rotation direction of the platen drum. Wherein the angle of the print screen to the center of the platen drum is greater than or equal to the angle of the print screen to the center of the platen drum. 3. The color thermal printer according to claim 1, wherein the tip of the effective irradiation range of the optical fixing lamp disposed next to the thermal head is positioned near immediately after the thermal head. 4. A color thermal printer according to claim 1, wherein the discharge port is provided near the rear end of the effective irradiation range of the second light fixing lamp.