JPS6349637B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention applies thermal energy according to the image to a thermal ink film by raster scan to form a thermal image, and thereby the melted ink film The present invention relates to a thermal ink supply device for a thermal recording device that transfers the above ink onto a recording medium to form an image.

2. Description of the Related Art In recent years, heat-sensitive recording has become especially popular in fields such as facsimiles and printers. A thermal recording unit consists of a thermal recording head that selectively converts electrical energy into thermal energy according to an image signal, and thermal recording paper that causes a chemical or physical reaction and develops color when supplied with thermal energy. ,
and peripheral mechanisms that drive and control them.

Thermosensitive recording is (a) primary color development (direct recording), so the device can be simplified and an inexpensive recording unit can be produced.

(b) The recording paper is one of the cheapest among processed papers (for example, electrostatic recording paper, discharge breakdown recording paper, etc.) and has low running costs.

(c) No noise, odor, electrical noise, etc. will be generated.

It has the following advantages. However, on the other hand (1) The recording paper is processed paper.

(2) Since recording cannot be fixed, it remains heat sensitive even after recording is completed.

(3) Not suitable for high-speed recording.

It also has the following drawbacks.

For this reason, in the past, for example,
As disclosed in Japanese Patent No. 17906, a light beam generated from a light source is irradiated onto a transparent carrier band through a template arrangement, locally softening a thermoplastic colorant layer provided on the carrier band, and coloring the recording carrier. In order to transfer the softened portion of the colorant layer, the carrier band is an endless band, and as a means of regenerating the colorant layer of the endless band, the colorant material stored in the storage tank is rolled up by a roller and then The colorant material is applied to the endless band by another provided roller, and the endless band coated with the colorant material is circulated to an intermediate portion between the template device and the recording carrier for recording. something is already provided.

However, such a conventional colorant material supply device is equipped with a roller device having two rollers to supply the colorant material in the storage tank to the endless band, and the storage tank is heated and colored. The colorant material is melted and two rollers are also heated to keep the colorant material in a molten state while applying it to the endless band, and the colorant material on the endless band is mixed with the remaining colorant material. It is mixed with colorant material supplied from the storage tank and regenerated. Then, both the remaining colorant material and the newly supplied colorant material are mixed in a sufficiently molten state so that the regenerated colorant layer has the same thickness and quality again when it leaves the roller device. The endless band has to be melted and fused, for which purpose it is provided that the endless band is preheated by means of a heating device in the area before entering the roller device.

Thus, conventionally, a plurality of rollers for rolling up and transferring the colorant material from a storage tank to an endless band, a device for heating the plurality of rollers and the storage tank, and a heating device for preheating the endless band The problem was that the configuration was complicated.

The present invention has been made based on the above points, and provides a thermal ink supply with a simple configuration in a thermal recording device that adopts a method of transferring thermal ink to plain paper without using processed paper (thermal recording paper). It provides equipment.

FIG. 1 is a cross-sectional view of a thermal ink film suitable for use in the present invention, in which 1 is a thermal recording head that holds a thermal image converted from an optical image or an electric signal corresponding thereto, and 3 is a thermal recording head having a thickness of several digits. 10 μm flexible base, 4 is a heat-sensitive ink layer, and 3 and 4 constitute a heat-sensitive ink film (ink holding medium) 2.

5 is a recording medium (plain paper, sheet-shaped resin, metal, leather, etc.) that is pressed into contact with the thermal ink film 2 under the thermal recording head 1; 4A is a recording medium that is melted by the thermal recording head 1 and pressed onto the recording medium 5 This is the ink transferred to.

As the thermal recording head 1, an ordinary thermal recording head that has been commonly used can be used, and it partially prints the thermal ink layer 4 in the thermal ink film 2 according to the image signal. It can be melted and transferred onto the recording medium 5.

FIG. 2 is a schematic diagram of a possible means for supplying ink to the thermal ink film as shown in FIG. , an ink wax 11 that melts when heated, and an ink wax tank 12. 8 is a back roll and 13 is a field roll.

As is clear from the figure, the thermal ink film 2 has a belt-like annular structure and rotates cyclically in the direction of the arrow. A thermal ink supply system 7 is provided in a part of the circulation path of the thermal ink film 2 to form a uniform thermal ink layer 4 having a constant thickness at all times.

That is, the heat-sensitive ink wax 11 is stored in the ink wax tank 12, and only the portion of the ink wax 11 near the interface with the heat-sensitive ink film 2 is constantly heated by the heat roll 9 and melted. As the belt-shaped heat-sensitive ink film 2 circulates in the direction of the arrow, molten ink wax is applied onto it.

At this time, the plate 10 serves to form the heat-sensitive ink layer 4 into a uniform layer with a constant thickness. In addition,
Of course, other heating means such as a heat plate can be used in place of the heat roll 9.

In addition, as in a general thermal recording unit, a back roll 8 is provided to efficiently transmit the thermal energy (thermal image) generated by the thermal recording head 1 in response to the image signal to the thermal ink layer 4. 5
It is also desirable to press the thermal ink film belt 2 against the thermal recording head 1.

The heat roll 9 functions to once melt the ink wax 11 and apply it uniformly onto the base 3 to form the heat-sensitive ink layer 4. This heat roll is made of a metal pipe, and a heater is installed inside the heat roll to control the temperature so that the pipe surface temperature is always about 100 to 150°C.

The effect of melting only the heat-sensitive ink wax 11 in the ink wax tank 12 near the interface with the heat-sensitive ink film is to prevent deterioration of the ink wax due to oxidation or the like.

FIG. 3 is a schematic diagram of main parts of an embodiment of the present invention,
A heat roll 9 as described above is interposed between the ink wax tank 12 and the heat-sensitive ink film 2.

In this embodiment, a part of the circumferential surface of the heat roll 9 directly contacts the heat-sensitive ink wax 11 to partially melt the heat-sensitive ink wax 11. The heat-sensitive ink layer side of the heat-sensitive ink film 2 is brought into surface contact with the other peripheral surface that is not in contact with the heat-sensitive ink film 2 .

The tension rolls 15 and 16 are provided so as to be in contact with the base surface of the heat-sensitive ink film, and the relative positional relationship between the tension rolls 15 and 16 allows the heat roll 9
The area of the portion of the circumferential surface of the heat roll that contacts the surface of the heat-sensitive ink layer of the heat-sensitive film 2, that is, the size of the center angle range of the circumferential surface of the heat roll is determined.

In this case, since the heat-sensitive ink wax 11 in the ink wax tank 12 comes into direct contact with the heat roll 9, a part of it is efficiently melted and once coated on the surface of the heat roll 9, and is kept at a high temperature.

The heat roll 9 also temporarily removes the thermal ink layer 4 that was left on the thermal ink film 2 without being transferred in the contact area (area indicated by A in FIG. 3) where it makes surface contact with the thermal ink film 2. It is melted and mixed with the molten thermal ink on the heat roll 9 to regenerate a new uniform thermal ink layer 4 without using any special ink thickness adjustment means.

Furthermore, in this case, the residual ink layer on the thermal ink film 2 comes into direct contact with the surface of the heat roll 9 without going through the base 3, so that it is not remelted by the heat roll 9 and melted on its surface. Mixing with the thermal ink becomes more complete.

Therefore, for example, thermal ink film,
The heat-sensitive ink layer 4 with excellent thickness uniformity can be generated with a simple configuration without providing a heating device or the like for preheating the area before reaching the heat roll 9.

In this embodiment, the heat-sensitive ink wax 11 attached to a part of the circumferential surface of the heat roll 9 is directly applied to the heat-sensitive ink film 2 without using any other means. The thermal ink wax 11 can be applied to the thermal ink film 2 without giving time for it to solidify.

In this way, in this embodiment, only the heat-sensitive ink wax 11 that is in surface contact with the circumferential surface of the heat roll 9 and the heat-sensitive ink wax 11 in the vicinity thereof is heated, so that the heat-sensitive ink wax 11 may deteriorate due to oxidation caused by unnecessary heating. It can be prevented.

In addition, especially when increasing the transfer speed or downsizing the device, the thermal ink film 2 advances from the ink wax supply system 7 to the position of the thermal head 1 and back roll 8 where the recorded image is transferred. It takes less time.

For this reason, the heat-sensitive ink layer 4 may come into contact with the recording paper 5 before it has sufficiently cooled and become solid, thereby staining the non-image area (background area). In order to avoid this, as indicated by the dotted line in FIG. 2, it is necessary to install a blower or the like between the ink wax supply system 7 and the transfer position to cool and solidify the thermal ink layer 4 on the ink film 3. It is preferable to provide a cooler 14 typified by: The case of FIG. 3 is exactly the same.

Further, in the above embodiment, a thermal ink supply system in a recording unit of a mechanism that melts and transfers thermal ink using a thermal element such as a thermal recording head has been described. To generate a thermal image, as shown in FIG. 4, electricity is applied to a film consisting of an electrically resistive layer 21, a conductive layer 22, and a heat-sensitive ink layer 23 via a multi-needle electrode 24 and plate electrodes 25 and 26 according to the image. It is clear that the present invention can also be applied as is to a thermal ink supply system in an electrically conductive thermal plain paper recording unit.

As described above, the present invention is capable of circulating a thermal ink film in a thermal plain paper recording unit or an electric thermal plain paper recording unit that partially heats and melts thermal ink according to an image and transfers the melted ink to a recording paper. An ink wax tank provided in a part of the moving path to store ink wax, and a heat roll whose surface is coated with molten ink wax from this ink wax tank are brought into surface contact with the heat-sensitive ink layer of the heat-sensitive ink film. Because of this structure, there is no need to provide a heating device to preheat the thermal ink layer of the thermal ink film in the area before it reaches the heat roll, and the thermal ink layer of the thermal ink film has a simple configuration and has excellent thickness uniformity. This makes it possible to regenerate the ink layer.

As is clear from the above description, according to the present invention, the following effects can be achieved.

(1) Since the heating means is in surface contact with the heat-sensitive ink film, heating efficiency is good.

(2) Since the heating means for the thermal ink film and the ink wax in the ink wax tank can be shared, the distance between the ink wax tank and the thermal ink film can be shortened, and as a result, the molten ink wax comes into contact with air. Since the time is shortened, deterioration of the ink wax due to oxidation can be prevented.

(3) Since only the ink wax in the ink wax tank that is in surface contact with the heating means and in the vicinity thereof is melted, the entire ink wax in the ink wax tank is melted and stirred, and the ink wax is mixed with air. There is no risk of oxidation due to contact.

(4) A means for heating the ink wax in the ink wax tank, a means for supplying and applying the molten ink wax to the thermal ink film, and a means for remelting the ink remaining on the thermal ink film without being transferred to the recording paper. Since the heating means can be configured using a common heating means, the device can be simplified and its reliability against failure can be improved, leading to a reduction in manufacturing costs.

[Brief explanation of the drawing]

1 and 4 are cross-sectional views of a thermal ink film used in the present invention, FIG. 2 is a schematic diagram of a possible thermal ink supply system, and FIG. 3 is a schematic diagram of a main part of an embodiment of the present invention. be. 2...Thermal ink film, 4...Thermal ink layer,
9... Heat roll, 11... Ink wax, 12
...Ink wax tank, 15,16...Tension roll.

Claims (1)

[Scope of Claims] 1. A thermal ink film formed in an annular shape having a base and a thermal ink layer applied to the surface of the base, and a thermal ink film that generates thermal energy according to an image signal to form a thermal ink film on the thermal ink film. means for generating a thermal image and thereby melting at least a portion of the thermal ink layer, the recording medium is brought into contact with the thermal ink layer, and the molten thermal ink is transferred to the recording medium. In a thermal ink supply device of a thermal recording device, an ink wax tank is provided in a part of a circulation path of a thermal ink film and stores ink wax, and the ink wax in a molten state from the ink wax tank is deposited on the surface of the ink wax tank. A heat-sensitive ink supply device for a heat-sensitive recording device, comprising: a rotatable heat roll coated with the heat-sensitive ink layer and in surface contact with the heat-sensitive ink layer of the heat-sensitive ink film.