JPH0768811A - Transfer printer - Google Patents

Abstract

PURPOSE:To enable accurate color reproduction by a method wherein a plurality of solid inks are applied to an ink conveying member under the same condition by pushing the solid inks against the ink conveying member by the same pressure always, through which color balance is made favorable by eliminating a difference in transfer image density of colors each. CONSTITUTION:In a transfer type printer, solid inks 41y, 41m, 41c of three primary colors are applied to a glass disc 16, the applied ink is transferred onto recording paper in accordance with recording information, an air bag 72 transmitting force by a pressing mechanism 70 evenly to the solid inks 41y, 41m, 41c is provided among a plurality of solid inks 41y, 41m, 41c and the pressing mechanism 70 pressing these solid inks 41y, 41m, 41c toward the glass disc 16. Furthermore, the pressing mechanism 70 possesses the first pressing shaft 77 pressing the air bag 72 through a spring 75 and the air bag 72 is pressed so that a distance between the first pressing shaft 77 and air bag 72 is kept constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer type printer in which solid ink is applied to an ink carrying member and the ink applied to the ink carrying member is transferred onto a recording medium according to recording information.

[0002]

2. Description of the Related Art At present, as a recording method of a printer for recording a full-color image on a recording medium, a thermal transfer method of thermally transferring ink is effective in terms of color reproducibility. In a conventional thermal transfer printer, an ink film having an ink layer formed on a film substrate is used, and a full-color image is formed by a frame sequential method using a thermal head. In the frame-sequential system, three colors of yellow (Y), magenta (M), and cyan (C)
Each primary color ink layer is arranged on the ink film, only the yellow image is printed on the entire surface of the recording medium first, and the magenta and cyan colors are sequentially superimposed and transferred onto the yellow image to transfer the color image. It is formed on a recording medium.

Further, in order to increase the recording speed, a printer has been developed in which the ink in the ink layer is irradiated with laser light in place of heating by a thermal head to thermally transfer the ink in the ink layer onto the recording medium. (JP-A-5
9-55,766, JP-A-2-175,291).

Further, a printer has been developed in which a liquid ink is repeatedly applied to a film base material of an ink film to reproduce an ink layer (JP-A-63-63).
39, 356, and Japanese Utility Model Laid-Open No. 53-35,038). By regenerating the ink layer on the ink film in this manner, the problem that the ink film having a large amount of unused ink remaining must be discarded is solved.

However, the above-mentioned publication (Japanese Patent Laid-Open No. Sho 63-63)
In the techniques of JP-A-39,356 and JP-A-53-35,038, the film base material to which ink is repeatedly applied is not so strong and the ink layer is stably regenerated for a long period of time. Therefore, it was difficult to stably form a high-quality color image for a long period of time.

Therefore, the inventor of the present application applies the solid ink to the ink conveying member made of glass to stably reproduce the ink layer for a long period of time, thereby eliminating waste of ink and the like and forming a high quality image. We proposed a laser thermal transfer printer capable of forming stably over a long period of time (Japanese Patent Application No. 5-40,219).

[0007]

In a transfer type printer of the type in which solid ink is applied to an ink conveying member to reproduce the ink layer, and the ink in the ink layer is transferred onto a recording medium according to recording information. , Yellow (Y), magenta (M), and cyan (C) inks of three primary colors must be urged against the ink transport member with the same pressure and applied to the ink transport member under the same conditions. . This is because if the inks of the respective colors are not applied under the same conditions, the transferred image densities of the respective colors are different and the color balance is lost, resulting in an image with poor color reproducibility.

Here, a mechanism shown in FIG. 10 can be considered as a mechanism for applying the inks of the three primary colors to the ink conveying member. In the illustrated mechanism, each solid ink 4 of three primary colors of yellow (Y), magenta (M), and cyan (C) applied to a glass disk 16 as an ink transport member is used.
1 (generic name of 41 _y , 41 _m , and 41 _c ) is housed in the ink cartridge 90. Ink cartridge 90
Is required to press the solid ink 41 against the glass disk 16. Therefore, the first pressing plate 91 (91 _y , abutting against the rear end surface of each solid ink 41,
91 _m , 91 _c ) (collective name of 91 _m and 91 _c ) are housed in the ink cartridge 90 so as to be movable back and forth with respect to the glass disk
A first pressing plate 91 is provided between the first pressing plate 91 and the second pressing plate 93 (general term 93 _y , 93 _m , 93 _c ) attached to the bottom plate 92 fixed in the ink cartridge 90.
Spring 94 (general term for 94 _y , 94 _m , and 94 _c ) that applies a spring force in the direction of moving the glass toward the glass disk 16.
Is attached.

However, the ink cartridge having this structure has the following problems. First, since the solid ink 41 of each color is individually pressed by the spring 94, it is difficult to set the pressing force for pressing the solid ink 41 against the glass disk 16 to a uniform pressure for each color. If the solid inks 41 of the three primary colors are not pressed against the glass disk 16 with the same pressure, as described above, the ink densities on the glass disks 16 of the respective colors differ, resulting in an image with poor color balance. turn into.

Second, the principle of the spring (P = kX: repulsive force P
Is equal to the spring constant k multiplied by the length X pushed in), and as the solid ink 41 decreases and becomes shorter, the pressing force for pressing the solid ink 41 against the glass disk 16 decreases. Is mentioned. Solid ink 4
The pressing force against the glass disk 16 of 1 is the solid ink 4
If the number fluctuates with the use of No. 1, it becomes impossible to stably form a high-quality color image with a good color balance on a plurality of sheets.

In order to improve these drawbacks, the spring 94 is selected in order to eliminate the influence of manufacturing variations of the spring 94, and a spring pressure adjusting mechanism for adjusting the decrease in the pressing force due to the use of the solid ink 41 is separately provided. However, these not only increase the cost but also increase the adjustment man-hours, which causes a problem that the operability of the printer is deteriorated.

The present invention has been made in order to solve the above problems, and a plurality of solid inks are always pressed against the ink conveying member at the same pressure to convey the plurality of solid inks under the same conditions. An object of the present invention is to provide a transfer type printer which is applied to a member and thereby eliminates a difference in transfer image density of each color to improve color balance and enables faithful color reproduction.

[0013]

SUMMARY OF THE INVENTION To achieve the above object, the present invention applies solid ink to an ink conveying member and transfers the ink applied to the ink conveying member onto a recording medium according to recording information. In the transfer printer of the type, a pressure that evenly transmits the force by the pressing mechanism between the plurality of solid inks and the pressing mechanism that presses the solid inks toward the ink transport member. A transfer-type printer having a transmission member.

The pressing mechanism has a pressing member for pressing the pressure transmitting member via an elastic means, and
The pressure transmitting member is pressed so that the distance between the pressing member and the pressure transmitting member is kept constant.

[0015]

By the pressure transmitting member provided between the pressing mechanism and the plurality of solid inks, the force of the pressing mechanism is evenly transmitted to each solid ink, and each solid ink is pressed against the ink conveying member with the same pressure. . Since the pressing force on the ink carrying member is the same for each solid ink, a plurality of solid inks are applied to the ink carrying member under the same conditions, and as a result, there is no difference in the transfer image density of each color The balance is stabilized, the color balance of the output image is stable and good, and an image having excellent color reproducibility is formed.

Further, since the pressing mechanism presses the pressure transmitting member while keeping the distance between the pressing member and the pressure transmitting member constant, a constant pushing force can be always obtained, and the solid ink is The pressing force is maintained at a predetermined constant pressure from the start to the end of use of the solid ink. As a result, images having excellent color reproducibility are stably formed on a plurality of sheets.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. 1 is a schematic configuration diagram showing a laser thermal transfer printer according to an embodiment of the present invention, and FIG.
A cross-sectional view taken along line -2, and FIG. 3 is a perspective view showing a main part of FIG. In FIG. 1, the scale ratios of the drum and other members are made different in order to facilitate understanding of the overall configuration of the printer.

First, the overall structure of the laser thermal transfer printer according to this embodiment will be outlined with reference to FIGS. 1 and 2.

The laser thermal transfer printer 10 irradiates the ink layer 11 with a laser beam L to transfer the ink to a recording paper or the like as a recording medium, and is a sublimation type in which a sublimable dye is used in the ink. Is a thermal transfer printer.
The printer 10 is provided with a rotatable drum 14 supported by a support shaft 13, and a color image forming means 15 for forming a color image on the recording paper 12 wound around the drum 14. Color image forming means 15
Is a glass disk 16 (corresponding to an ink carrying member) that does not use an ink film, is provided with three color ink layers 11 on the disk-shaped outer peripheral surface, and is capable of transmitting laser light L, and this glass disk. Laser light irradiation switching means 17 for irradiating the ink layer 11 on 16 with the laser light L and selectively switching the ink layer 11 to be irradiated with the laser light L, and constantly replenishing the ink sublimated in the image forming process. And an ink layer regenerating means 18 for regenerating the ink layer 11.

The glass disk 16 is arranged so that its outer peripheral surface faces the drum 14 around which the recording paper 12 is wound, and is stored in the carriage 19 together with the ink layer reproducing means 18. The carriage 19 is movably provided along a guide shaft 20 arranged in parallel with the support shaft 13, and the glass disc 16 is rotatably supported by the guide shaft 20. Further, the motor 21 for driving the glass disk 16 to rotate is mounted on the carriage 1.
It is provided in 9.

The laser light irradiation switching means 17 has a laser diode 22 which is a semiconductor laser. The laser light L oscillated from this laser diode 22 is shaped through an optical system 23 and then is first mirror M1. , Second
It is folded back by the mirror M2 and the third mirror M3. The laser light L folded back by the third mirror M3 is irradiated from the inner side in the radial direction of the glass disk 16 toward the outer side in the radial direction, and is irradiated onto the ink layer 11 provided on the outer peripheral surface. As a result, the ink of the ink layer 11 is excited and dyed on the image receiving surface of the recording paper 12. Second mirror M
2 is provided so as to be movable along the direction shown by the arrow in the figure, and by moving the second mirror M2, the incident position of the laser light L on the third mirror M3 is changed and the laser light L is irradiated. The ink layer 11 to be used is selectively switchable. The sub scanning is performed by moving the carriage 19 along the guide shaft 20, and the main scanning is performed by rotating the drum 14.

Next, each component will be described in more detail.

Recording paper 1 wound around the drum 14
The sheets 2 are accommodated in a sheet feed cassette or the like (not shown) in a stacked state. The recording sheet is fed by a sheet feeding roller, conveyed by a conveying roller, and wound around the drum 14.

The glass disk 16 is formed of glass which is a non-infrared absorbing material, and as the material of this glass, quartz or calcium fluoride, which absorbs little at the wavelength of the semiconductor laser 22 used, is used.
As shown in FIGS. 3 and 4, the glass disc 16 has a disc-shaped overall shape, and is provided with an outer ring portion 25 and an inner ring portion 26. Both the inner and outer ring portions 25, 26 are provided. A ring-shaped recess 27 is formed between them. On the outer peripheral surface 31 of the outer ring portion 25, that is, the end surface facing the recording paper 12, three color ink layers 11 (11 _y , 11 _y
m , a generic name of 11 _c ) and three groove portions 28 for accommodating
(Collective name of 28 _y , 28 _m , and 28 _c ) is formed.
On the other hand, the inner ring portion 26 is formed with a through hole 29 into which the guide shaft 20 is inserted.

A drive roller 30 is connected to the motor 21 provided in the carriage 19, and the drive roller 30 is arranged in the ring-shaped recess 27 so as to contact the outer peripheral surface 33 of the inner ring portion 26. . The drive roller 30 is driven by the motor 21 so that the glass disk 1
6 is rotationally driven. During image formation, drum 1
4 and the glass disk 16 are synchronized so that the peripheral speed of the drum 14 and the peripheral speed of the glass disk 16 match. In the ring-shaped recess 27, a third mirror M3 is further arranged so as not to interfere with the rotational movement of the glass disk 16. The third mirror M3 is fixed to the carriage 19 in a state in which the reflected laser light L is inclined at an angle at which the reflected laser light L is incident perpendicularly on the inner peripheral surface 32 of the outer ring portion 25. In this way, the inner peripheral surface 32 of the outer ring portion 25 becomes an incident surface on which the laser light L folded back by the third mirror M3 is incident, so that it is mirror-finished and is given a non-reflective coating so as to have a surface roughness. Loss due to scattering and reflection due to is minimized. Further, since it is necessary to prevent the scattering of the laser light L also on the bottom surfaces 34 of the three groove portions 28,
It is mirror-finished.

Each of the groove portions 28 accommodates the ink layers 11 of the three primary colors of yellow (Y), magenta (M) and cyan (C), and the first groove portion 2 at the uppermost stage in FIG.
The yellow ink layer 11 _y is provided on the 8 _y , and the second groove portion 2 in the middle stage is provided.
The magenta ink layer 11 _m is accommodated in 8 _m , and the cyan ink layer 11 _c is accommodated in the lowermost third groove 28 _c . Note that the arrangement of each color is not specified in this order.

In FIG. 5, the groove portion 28 and the recording paper 12 are shown enlarged, and the outer peripheral surface of the glass disk 16 is in contact with the image receiving surface 35 of the recording paper 12 wound around the drum. Reference numeral "36" indicates a paper base material. Each groove 28 has a bottom surface 34 on the center side of the glass disk 16.
The heat insulating layer 37 and the carbon layer 38 are sequentially laminated from the side toward the outer peripheral surface 31 side, and the ink layer 11 is further applied from above the carbon layer 38. The carbon layer 38 functions as a photothermal conversion layer that absorbs the laser light L and generates heat.
An air gap 39 of about 30 μm is formed between the surface of the ink layer 11 and the outer peripheral surface 31 of the glass disk 16, and the image receiving layer 35 and the ink layer 11 are kept at a close distance. The depth from the outer peripheral surface 31 of the glass disk 16 to the bottom surface 34 of the groove 28 is set to a length such that the air gap 39 can be maintained even when the heat insulating layer 37, the carbon layer 38, and the ink layer 11 are laminated. The laser light L vertically incident on the bottom surface 34 of the groove 28 is absorbed by the carbon layer 38 via the heat insulating layer 37. The carbon layer 38 is baked on the glass disk 16 with a thickness capable of absorbing 80% or more of the laser light L. The reason why the carbon layer 38 is baked is that the image quality of the transferred image is deteriorated when the carbon scatters together with the ink. When the carbon layer 38 absorbs the laser light L, it becomes 300.
Generates heat of ℃ or more, and this heat is transmitted to the ink layer 11,
The sublimable dye is sublimated by heat energy. The sublimated ink is trapped in the image receiving layer 35 of the recording paper 12, and as a result, the recording paper 12 is dyed to form an image. The heat insulating layer 37 provided between the groove bottom surface 34 and the carbon layer 38 prevents the heat generated in the carbon layer 38 from being immediately transferred to the glass, which is the material of the glass disk 16, to be radiated.

The spot diameter of the laser beam L is 3 larger than the finally desired dot diameter in consideration of the fact that the ink spreads radially in the process of reaching the image receiving layer 35 of the recording paper 12 through the air gap 39. Set so that it is relatively small. For example, resolution 300 DPI, dot diameter φ84 μm
When, the spot diameter is about φ59 μm. Further, as the semiconductor laser, it is preferable to use a high power type of 1000 mW class (for example, SLD304XT manufactured by Sony Corporation).

The first mirror M1 and the second mirror M2
1 is housed in a mirror case 24 arranged coaxially with the carriage 19, as shown in FIG. The mirror case 24 is movably provided along the guide shaft 20. When the carriage 19 moves, the mirror case 24 moves in the same direction as the moving direction of the carriage 19 by 1/2 of the moving amount of the carriage 19 = 1.
The reason for moving the mirror case 24 in this way is as follows. That is, when the carriage 19 moves in the direction along the guide axis 20, that is, in the sub-scanning direction, the optical path length from the laser diode 22 to the outer peripheral surface 31 of the glass disk 16 changes, and the laser light L defocuses to blur the image. Will end up. This is because by moving the mirror case 24 as described above, a correction for a change in the optical path length is added, a constant optical path length is maintained, and image blurring is prevented. The first mirror M1 has an optical system 2
The second mirror M2 is attached to the position where the laser light L that has passed through 3 is incident, and the second mirror M2 is positioned with respect to the first mirror indicated by the arrow at the position where the laser light L reflected by the first mirror M1 is incident. It is provided so as to be movable along the direction of approaching and separating. The third mirror M3 is attached to the carriage 19 as described above.

When performing a color change, as shown in FIG. 4, the second mirror M2 is moved in the direction of the arrow,
The incident position of the laser light L on the third mirror M3 is changed, and the ink layer 11 to be irradiated with the laser light L is switched. That is, the second mirror M2 is the first mirror in FIG.
When it is moved to the position P _y (the position farthest from the first mirror M1 in FIG. 1), the incident position comes to the rightmost position in FIG. 4, and the laser beam L folded back by the third mirror M3. Is irradiated to the first groove 28 _y , and yellow ink is excited. Similarly, the second mirror M2
4 is moved to the third position P _c in FIG. 4 (the position closest to the first mirror M1 in FIG. 1), the incident position becomes the leftmost position in FIG. The third groove 28 _c is irradiated and the cyan ink is excited. In addition, the second mirror M2 is the second mirror in FIG.
When the laser beam L is moved to the position P _m , the laser beam L is moved to the second groove 2
Irradiate 8 _m to excite magenta ink.

In this embodiment, the change in the optical path length due to the movement of the second mirror M2 is not corrected, but the movement amount of the second mirror M2 is small and the change in the optical path length is small. Therefore, even if the correction is not performed, the focus of the laser light L does not deviate, and the image does not blur.

The ink layer regenerating means 18 (18 _y , 18)
_As shown in FIG. 4, three _m , 18 _c are collectively provided in the carriage 19 for reproducing the yellow, magenta, and cyan ink layers 11 _y , 11 _m , and 11 _c , respectively. As shown in FIG. 2, these ink layer reproducing means 18 are provided on the circumference of the glass disk 16 at positions apart from the drum 14.

As shown in FIG. 3, the ink layer reproducing means 18 contains solid inks 41 of yellow, magenta and cyan and presses the solid ink 41 against the groove 28 of the glass disk 16 to apply the ink. (See also FIG. 7), a pressing roller 43 that crushes the applied ink, and a blade 44 that shapes the ink into a uniform layer.
And a pressing mechanism 70 (see also FIG. 7) that is provided on the printer body side and presses the solid ink 41 toward the glass disk 16. The ink applying member 42 and the pressing mechanism 70 form the glass disk 1
Solid ink 4 for yellow, magenta, and cyan for 6
The pressure contact force of 1 is always the same, and moreover, the pressure is kept constant. In FIG. 3, the pressing roller 43
As for the shaping member 45, only those involved in the reproduction of the yellow ink layer 11 _y are shown, and the other two ink layers 11 _y are shown.
_Although not shown in the drawings, those involved in the reproduction of _{m 1} and 11 _c have the same configuration.

First, the principle of regenerating the ink layer 11 by the ink layer regenerating means 18 will be described with reference to FIG. This Figure 6
, The bottom surface 34 of the groove portion 28 is shown as a plane, and the solid ink 41, the pressing roller 43, and the blade 44 are arranged in this order from the upstream side along the rotation direction of the glass disk 16 shown by the arrow R. The solid ink 41 is formed in a solid state (for example, a crayon shape) by dispersing the ink in a wax such as carnauba wax, and the groove portion 28.
The ink mixed with the wax is applied to the groove portion 28 by being pressed against and being slightly heated at the tip portion. The surface of the ink layer 11 at this stage is still rough and is crushed by the next pressing roller 43 as the glass disk 16 rotates. Then, the ink layer 11 is shaped into a uniform layer by being further stretched by the blade 44 that is slightly heated.

Next, each component of the ink layer regenerating means 18 will be described in detail. As shown in FIG. 7, the ink applying member 42 includes an ink cartridge 48 including a main body 46 having a box shape and a guide case 47 connected to the main body 46, and is accommodated in the main body 46. Each of the solid inks 41 of the three primary colors can be exposed at its tip through a window 49 formed in the guide case 47. Body 46
Is formed of a plastic material, and the guide case 47 is formed of a metal material having good thermal conductivity such as aluminum. The guide case 47 includes a heater 50 for heating the guide case 47 and a thermistor 51 for detecting the temperature of the guide case 47. With the heater 50 and the thermistor 51, the guide case 4
Heating control is performed to uniformly heat 7 to a predetermined temperature, and the tip portion of the solid ink 41 is heated to about 40 ° C. This heating softens the tip of the solid ink 41 to facilitate application of the ink to the groove 28. The heating control for the guide case 47 is performed to maintain the optimum ink hardness when the solid ink 41 is applied to the groove portion 28, but the temperature of the guide case 47 is suppressed to a temperature level at which the ink does not sublime. is there. Further, in order to prevent only the tip end portion of the solid ink 41 from being heated and the other portions not to be heated, the main body portion 46 is formed of the plastic material exhibiting the heat insulating effect as described above.

In the ink cartridge 48, push blocks 71 (collectively referred to as 71 _y , 71 _m , and 71 _c ), one end of which is in contact with the rear end surface of each solid ink 41, are movable back and forth with respect to the glass disk 16. It is provided. A pressure transmitting member 72 that evenly transmits the force of the pressing mechanism 70 to each solid ink 41 is disposed between the other end surface side of these push blocks 71 and the pressing mechanism 70 described later. The pressure transmission member 72 is composed of, for example, an air bag in which air of 1 atm or more is enclosed in a bag member 73 made of a flexible elastic body such as rubber. The air bag 72 filled with air has a constant pressure to the outside wherever it is seen, and has a property that when a large external pressure is applied to one place and it is dented, the corresponding pressure is spilled to other places. There is. Since each of the push blocks 71 is in contact with one airbag 72 having such a property, the force applied from the airbag 72 to each push block 71 is equal to that of each push block 71. In the solid ink 41 shown in FIG. 7, there is a difference in ink consumption amount for each color of yellow, magenta, and cyan, and the remaining amount of the magenta solid ink 41 _m is small. Is the same in all parts, the pressing force of the solid ink 41 against the glass disk 16 is the same for each color of yellow, magenta, and cyan. The pressure inside the airbag 72 is the solid ink 41.
The tip end surface of the solid ink 41 is reliably pressed against the groove portion 28 by being urged against.

In the ink cartridge 48, the plate 7 which is movable back and forth with respect to the push block 71 is further provided.
4 is provided, and one side of the airbag 72 is held by a plate 74 and is movable back and forth with respect to the push block 71. The plate 74 is formed of, for example, a metal material that does not easily deform even when pressed by the pressing mechanism 70. Assuming that the position of the plate 74 in the ink cartridge 48 does not change, the pressure in the airbag 72 decreases as the solid ink 41 decreases, so the pressure contact force of the solid ink 41 decreases. I will end up. In order to prevent such a variation in the pressure contact force of the solid ink 41, a pressing mechanism 70 that pushes the airbag 72 toward the push block 71 via the plate 74 is provided.

The pressing mechanism 70 has a pressing member for pressing the airbag 72 via a spring 75 as an elastic means, and maintains the distance between the pressing member and the airbag 72 constant. It is configured to press the bag 72. More specifically, the pressing mechanism 7
Reference numeral 0 denotes a first pressing shaft 77 (corresponding to a pressing member) which is driven by a motor M via a gear train 76 and moves back and forth with respect to the plate 74, and a through hole formed in the main body 46 of the ink cartridge 48. And a second pressing shaft 78 that is inserted through 46a and contacts the plate 74. The tip 77a of the first pressing shaft 77 is slidably inserted into a bottomed hole 78a formed in the second pressing portion 78, and a spring 75 is provided between the tip 77a and the bottomed hole 78a. Is provided. Therefore, the second pressing shaft 78 is pressed from the first pressing shaft 77 via the spring 75. The gear train 76 is the first gear 7 connected to the output shaft of the motor M.
9 and the first gear 79 and the gear receiving portion 8
And a second gear 81 rotatably supported at 0. The motor M and the gear receiving portion 80 are fixed to predetermined positions of the printer body, and the female screw 81a formed on the inner peripheral surface of the second gear 81 and the male screw 77b formed on the base end portion of the first pressing shaft 77 are provided. It is in mesh. The motor M is rotatable in both forward and reverse directions, and when the motor M rotates in forward and reverse proper directions, the second gear 81 is rotationally driven by the first gear 79, and the first pressing shaft 77 is rotationally driven and the second pressing force is applied. It moves forward or backward with respect to the shaft 78. The solid arrows in FIG. 7 indicate that the solid ink 41 has decreased and the first and second pressing shafts 7 have
The rotation directions of the gears 79 and 80 and the movement direction of the first pressing shaft 77 when the 7, 7 are further pushed toward the plate 74 are shown. That is, when the first gear 79 rotates right, the second gear 81 rotates left, the first pressing shaft 77 moves forward, and the second pressing shaft 78 is pushed out toward the plate 74 via the spring 75.

As shown in FIG. 8A, the first pressing shaft 7
7 between the flange portion 82 provided on the second pressing shaft 78 and the flange portion 82 provided on the second pressing shaft 78,
Distance detection means 84 for detecting the distance between 78 is provided. The distance detecting means 84 is composed of, for example, a reflection type photo sensor, and a reflection type photo sensor 85 including a light emitting element and a light receiving element is provided on the flange portion 82 of the first pressing shaft 77 to detect light from the light emitting element. A reflecting surface 86 that reflects and reaches the light receiving element is provided on the flange portion 83 of the second pressing shaft 78. The output signal from the light receiving element of the reflection type photo sensor 85 is input to the control means 87, and the control means 87.
Controls the rotation of the motor M in the proper forward and reverse directions by a predetermined amount based on this output signal.

Since the repulsive force of the spring 75 is constant if the pushing length is constant, the first and second pressing shafts 77, 77
By keeping the distance between 78, that is, the distance between the reflective photosensor 85 and the reflective surface 86 constant, the solid ink 41
It is possible to maintain the contact pressure of the glass disk 16 against the glass disk 16 at a predetermined pressure.

FIG. 8B is a characteristic diagram showing the output level characteristic of the reflective photosensor having a focal length of 4 mm. The reflective photosensor 85 has a fixed focal length due to its characteristic. When the distance between the sensor 85 and the reflecting surface 86 is kept at a predetermined focal length (4 mm in the illustrated example), the sensor 85 is in the highest level output state, and the sensor 85 and the reflecting surface are in comparison with the focal length. It has a characteristic that the output level is lowered even if the distance to 86 is short or long.

Therefore, when a proper pressure is applied to the spring 75, the distance between the reflection type photo sensor 85 and the reflection surface 86 is set to be equal to the focal length of the sensor 85, and thereafter, the reflection type photo sensor is set. If the control means 87 rotates the motor M by a predetermined amount in forward and backward proper directions so that the output level of the sensor 85 is always the highest, the distance between the first and second pressing shafts 77 and 78 becomes constant and always. A constant pushing force can be obtained. In this way, the control of the amount of extension of the first pressing shaft 77, that is, the amount of pushing of the airbag 72 via the spring 75 is performed based on the output signal from the reflective photosensor 85.

The reflective photosensor 85 has a characteristic that the amount of decrease in the output level is larger when the sensor 85 and the reflecting surface 86 are farther than the focal length than when they are closer than the focal length. is doing. Further, the reflection type photo sensor 85 shows an example of the distance detecting means 84 and is not limited to this, and other well-known sensors or technical means capable of measuring distance can be used.

As shown in FIG. 3, the pressing roller 43 is rotatably provided so as to be in pressure contact with the outer peripheral surface of the glass disk 16 and to rotate the surface of the ink layer 11 applied by the ink applying member 42. Crush with it.

As shown in FIG. 9, the shaping member 45 includes an arm-shaped blade 44 and a support member 55 that supports the blade 44. Since the tip portion of the blade 44 is a portion that comes into sliding contact with the end surface of the glass disk 16, a flexible silicone rubber 5 is used so as not to damage the glass surface.
6th grade is worn. Blade 44 and support member 55
Is formed of a metal material having good thermal conductivity such as aluminum. A heater 57 for heating the supporting member 55 and the blade 44 is built in the supporting member 55, and a thermistor 58 for detecting the temperature of the blade 44 is built in near the tip of the blade 44. These heaters 5
The 7 and the thermistor 58 control the heating of the tip of the blade 44 to about 40 ° C. Blade 4
The heating of No. 4 makes it easy to spread the ink crushed by the pressing roller 43. The heating control for the blade 44 is performed in order to maintain an optimum temperature when the ink is stretched. The temperature of the tip of the blade 44 is preferably high considering the stretchability of the ink, but the ink may sublime. In order to prevent this, the temperature level is kept at about 40 ° C. mentioned above. The blade 44 may have a heater built therein, while the support member 55 may be made of a plastic material having a heat insulating effect.

Next, the operation of this embodiment will be described.

First, in order to form a yellow image for one line on the recording paper 12 wound around the drum 14, the second
The mirror M2 is moved to the first position P _y shown in FIG. 4, and the laser light L from the laser diode 22 according to the image signal.
Is oscillated. At the same time, the glass disc 16
It is rotationally driven by the drive roller 30 so that the peripheral speed of the glass disk 16 matches the peripheral speed of the drum 14. Laser light L after being shaped through the optical system 23
Is folded back by the first mirror M1, the second mirror M2, and the third mirror M3. As shown in FIG. 4, the laser light L is incident on the glass disk 16 from the inner peripheral surface 32 of the outer ring portion 25 and is perpendicular to the bottom surface 34 of the first groove portion 28 _y . When the laser light L is absorbed by the carbon layer 38 via the heat insulating layer 37, the carbon layer 38 is absorbed by the carbon layer 38.
Heat of 0 ° C. or more is generated, and this heat causes the ink layer 11 _y
The sublimable dye contained in sublimes. The sublimed ink is
It is trapped in the image receiving layer 35 of the recording paper 12 through the air gap 39. As a result, the recording paper 12 is dyed,
A yellow image is formed.

Then, in order to superimpose the magenta color on the same line on which the yellow image is formed, the carriage 1
9 and the mirror case 24 are adjusted and moved, and the second mirror M2 is moved to the second position P _m . When the glass disk 16 is rotationally driven and the laser light L is oscillated, the laser light L is folded back by the first mirror M1, the second mirror M2, and the third mirror M3, and the second groove portion 2 is formed.
The bottom surface 34 of 8 _m is irradiated vertically. Then, the carbon layer 38 generates heat due to the absorption of the laser beam L, the sublimable dye contained in the ink layer 11 _m is sublimated, and the sublimated ink is trapped in the image receiving layer 35 through the air gap 39. The magenta color is superimposed on the line of the image.

When the superposition of magenta color is completed, the carriage 19 and the mirror case 24 are adjusted and moved to superimpose the cyan color on the same line, and the second mirror M2 is moved to the third position _Pc. It When the glass disk 16 is rotationally driven and the laser light L is oscillated, the laser light L folded back by the third mirror M3.
It is irradiated perpendicularly to the bottom surface 34 of the third groove 28 _c. Then, in the same manner as described above, the sublimable dye contained in the ink layer 11 _c is sublimated, the sublimated ink is trapped in the image receiving layer 35 through the air gap 39, and the cyan color is further added on the line. Overlaid. This completes the formation of a full-color image for one line.

By repeating the above operation for the number of lines, a predetermined full-color image is formed on the entire surface of the recording paper 12.

In such an image forming process, the inks in the ink layers 11 _y , 11 _m , and 11 _c decrease with sublimation, but the ink layer reproducing means 18 _y , 18 _m ,
_18c , the solid ink 41 is repeatedly applied onto the glass disk 16 and reproduced in the following manner. Solid ink 4 contained in ink cartridge 48
The tip portion of 1 receives the pressure in the airbag 72 and the groove portion 2
The ink is heated to about 40 ° C. at which the ink does not sublime and is softened by the operation of the heater 50. Further, the blade 44 of the shaping member 45
Also, by the operation of the heater 57, the same is heated to about 40 ° C. Then, as the glass disk 16 rotates in the image forming process, the ink mixed with the wax of the solid ink 41 is applied to the groove portion 28 and is crushed by the pressing roller 43 that is in pressure contact with the glass disk 16,
By being further stretched by the blade 44,
The ink layer 11 in the groove 28 is shaped into a uniform layer and repeatedly reproduced.

In particular, in the printer of this embodiment, since one airbag 72 is arranged between the push block 71 and the pressing mechanism 70 so that each push block 71 abuts, yellow, magenta, cyan. Even when the remaining amount of the solid ink 41 of each color is different, the pressure contact force of the solid ink 41 to the glass disk 16 is the same for each color. In this way, since the same pressure is applied to the solid ink 41 of the three colors to contact the glass disk 16, the inks of the three primary colors are applied to the glass disk 16 under the same conditions. As a result, there is no difference in the transfer image density of each color of yellow, magenta, and cyan, that is, the density balance is stabilized, the color balance of the output image is stable and good, and an image with excellent color reproducibility is formed. Will be done.

Further, since the three solid inks 41 can be always brought into contact with the glass disk 16 at the same pressure in a stable state without selecting a spring or providing a spring pressure adjusting mechanism, it is cost effective. It is also excellent in weight saving and does not require spring pressure adjustment work, which greatly improves the operability of the printer.

Further, since the pressing mechanism 70 presses the airbag 72 while keeping the distance between the first and second pressing shafts 77 and 78 constant, a constant pushing force can be obtained. Therefore, the pressure contact force of the solid ink 41 with respect to the glass disk 16 can be maintained at a predetermined constant pressure from the start to the end of use of the solid ink 41, and a plurality of images having excellent color reproducibility can be obtained. Can be stably formed.

Further, since the pressure contact force of the solid ink 41 is maintained at a constant pressure based on the distance between the first and second pressing shafts 77 and 78, it is not necessary to use a relatively expensive pressure sensor, and the printer Can contribute to lower costs.

As in this embodiment, the thermal transfer printer 1 using the glass disk 16 as a medium for carrying ink.
The greatest feature of 0 is that when a full-color image is formed by superimposing three primary colors of yellow (Y), magenta (M), and cyan (C), it is possible to move the second mirror M2 slightly, It is to be able to quickly select the ink layer 11 to be irradiated with the light L, that is, the color of the ink. This is similar to the conventional thermal transfer recording method using an ink film, in which only the yellow image is printed on the entire surface of the recording paper first, and then the magenta and cyan colors are sequentially superposed on the area sequential method. You don't have to take it. In the thermal transfer printer using the frame sequential method,
There is a problem in that the accuracy of overlaying the inks is poor, stable color reproduction is difficult, and "color misregistration" is likely to occur. On the other hand, in the printer 10 of the present embodiment using the glass disk 16, the three colors can be switched by only a small operation of moving the second mirror M2, so that the image formation can be speeded up. It is possible to complete the superimposition of the three primary colors for each line and then move to the image formation of the next line, which facilitates the superimposition of the inks and significantly improves the accuracy thereof. Therefore, stable color reproduction can be realized, and a high-quality full-color image without "color shift" can be formed. Further, since the dye ink is used, the gradation is also excellent. further,
The user of the printer 10 can quickly check the quality of the color balance without waiting for the completion of printing on the entire surface of the recording paper 12.

In forming an image, an air gap 39 is provided between the ink layer 11 and the image receiving layer 35 so that both of them 11 and 3 are formed.
Since 5 is not contacted, substances other than ink are not transferred, and from this point also, a high-quality full-color image can be formed.

Moreover, since the ink film is not used and the ink layer 11 is reproduced on the glass disk 16 by the ink layer reproducing means 18, the ink film in which the ink is not used must be discarded. The drawbacks of conventional thermal transfer printers are improved. Further, since the ink layer 11 is reproduced on the glass disk 16 which is stronger than the film substrate, the ink layer 11 can be reproduced over a long period of time as compared with the case where the ink layer is reproduced on the film substrate. It is possible to perform stably, and as a result, it is possible to stably form a high quality image for a long period of time.

Further, in supplying the ink, since the solid ink 41 is put into or contained in the ink cartridge 48, the ink may be spilled or scattered as in the case of using liquid ink. There is no problem, and the complicated work of mounting the roll around which the ink film is wound becomes unnecessary.

In the above-mentioned embodiment, the case where the solid ink 41 of three primary colors is applied is illustrated, but the present invention is not limited to this case, and solids of a plurality of solid colors of two colors or four or more colors. It can be applied to a printer provided with the ink 41. Further, the pressure transmission member is not limited to the airbag 72 described above, and may be a member in which a liquid or gel-like material is enclosed in the bag member 73, and the pressing mechanism 70 may be used.
The structure is not limited to the structure in which air or the like is enclosed in the bag member 73 as long as the force from the can is evenly transmitted to each solid ink 41. Further, the elastic means interposed between the pressure transmitting member 72 and the pressing member 77 is not limited to the spring 75, and may be an elastic body such as rubber that exhibits a constant repulsive force as long as the pushing length is constant. Although the sublimation type thermal transfer printer has been described, the present invention can also be applied to a fusion type thermal transfer printer by changing the ink.

[0061]

As described above, according to the transfer type printer of the present invention, the pressure transmission member provided between the pressing mechanism and the plurality of solid inks allows the force of the pressing mechanism to be evenly applied to each solid ink. When transmitted, each solid ink is pressed against the ink transport member with the same pressure. Since the pressing force on the ink conveying member is the same pressure for each solid ink,
A plurality of solid inks are applied to the ink conveying member under the same conditions, and as a result, there is no difference in the transfer image density of each color, that is, the density balance is stabilized, and the color balance of the output image is stable and good. It is possible to form an image having excellent color reproducibility.

Further, since the pressing mechanism presses the pressure transmitting member while keeping the distance between the pressing member and the pressure transmitting member constant, it is possible to always obtain a constant pushing force, and the solid ink mentioned above can be obtained. The pressing force is maintained at a predetermined constant pressure from the start to the end of use of the solid ink, and as a result, an image excellent in color reproducibility can be stably formed on a plurality of sheets. It will be possible.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a laser thermal transfer printer according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a perspective view showing a main part of FIG.

FIG. 4 is a sectional view showing a glass disk.

FIG. 5 is an enlarged view showing details of a groove portion.

FIG. 6 is a conceptual diagram showing the principle of ink layer regeneration by the ink layer regeneration means.

FIG. 7 is a cross-sectional view showing an ink applying member and a pressing mechanism of the ink layer reproducing means.

FIG. 8A is a schematic configuration diagram showing a reflective photosensor that detects the distance between the first and second pressing axes, and FIG. 8B is a reflective photosensor with a focal length of 4 mm. It is a characteristic diagram which shows the characteristic of the output level of a photosensor.

FIG. 9 is a perspective view showing a shaping member of the ink layer reproducing means.

FIG. 10 is a cross-sectional view showing a configuration example that is easily conceivable as a mechanism for applying a plurality of solid inks to an ink transport member.

[Explanation of symbols]

10 ... Laser thermal transfer printer, 11 ... Ink layer, 12 ... Recording paper (recording medium), 16 ... Glass disk (ink carrying member), 18 ... Ink layer reproducing means,
41 ... Solid ink, 42 ... Ink applying member, 48 ... Ink cartridge, 70
... pressing mechanism, 71 ... push block 72 ... airbag (pressure transmitting member), 74 ... plate, 75 ... spring (elastic means), 77 ... first pressing shaft (pressing member), 78 ... second pressing shaft,
84 ... Distance detecting means / reflection type photo sensor.

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Claims (2)

[Claims] 1. A transfer type printer of the type in which solid ink is applied to an ink carrying member and the ink applied to the ink carrying member is transferred onto a recording medium according to recording information. A transfer printer, wherein a pressure transmission member that uniformly transmits the force of the pressing mechanism to each of the solid inks is provided between the solid ink and a pressing mechanism that presses the solid ink toward the ink conveying member. 2. The pressing mechanism has a pressing member for pressing the pressure transmitting member via an elastic means, and the pressure transmitting member keeps a constant distance between the pressing member and the pressure transmitting member. The transfer printer according to claim 1, wherein a member is pressed.