JPS61149397A - Ink carrier - Google Patents

Abstract

PURPOSE:To reduce diffusion of heat in lateral directions, by a method wherein a substance having anisotropic dispersion characteristics is mixed into either one of an ink and a support member, and thermal conduction characteristics are set to be higher in an ink-transferring direction than in directions perpendicular to the ink-transferring direction. CONSTITUTION:A ferromagnetic material 3 is dispersed in an ink solution 5, a magnetic field generating device is operated immediately after the ink is applied to a base film 2 together with a solvent, and the operation is continued at least until the solvent is completedly evaporated off to be a vapor 6. During this, the ferromagnetic material is maintained in the state of being forcibly orientated in a columnar shape by a magnetic flux 10, resulting in an ink sheet 1 in which the ink 4 is solidified while the ferromagnetic material 3 is left in the columnar form. An alternative method comprises applying the ink in a thermally melted state, and cooling it while impressing a magnetic field thereon. The ferromagnetic material may not be in a particulate form, and a substance which is originally acicular in shape is move effective, since such a substance has high mechanical strength in the longitudinal direction of the acicular shape.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an ink carrier used as a recording material for thermal transfer recording.

[Technical background of the invention and its problems]

Thermal transfer recording uses an ink ribbon coated with wax-like ink that melts with heat between the thermal head and the recording paper, which are formed by forming an array of heat-generating resistors on the surface that can individually control the flow rate. 7
A plain paper recording method is used, which uses the principle that only the ink in contact with the heating resistor melts and is attached to the recording paper 62. Conventionally, it has been suggested that such thermal transfer recording exhibits the following tendency. If the thermal energy supplied to the ink from the heating resistor is low, the transferability to the recording paper will be poor, and the fixing will be unstable because it will not adhere firmly.
Recording dot shape 4 = Deterioration of image quality appears, such as unevenness and a lot of noise. On the other hand, if there is too much thermal energy, 42.
This causes deterioration in image quality such as the recording pixel becoming larger than the area of one pixel and becoming swollen and fat.

A major problem is that the moderate thermal energy saving range between these two is narrow. Since thermal recording itself is sensitive to temperature K, the amount of energy input to the heating resistor has been controlled using conventional complicated circuits, but the current situation is that the effectiveness of this method cannot be said to be sufficient. In the case of thermal transfer, the above-mentioned optimal area moves due to the heat accumulation phenomenon unique to thermal recording, which is also a reason why control is difficult.

Another disadvantage is that it is necessary to use paper that has been processed to make the surface smoother in order to improve transferability.

[Purpose of the invention]

The present invention improves the above-mentioned drawbacks of the prior art, and aims to provide an ink carrier that exhibits less heat diffusion in the lateral direction.

[Summary of the invention]

In the ink carrier for so-called thermal transfer recording, a substance having anisotropic dispersion properties is mixed into either the ink or the holding member, and the heat conduction properties along the ink transfer direction (; Ink transfer direction N
It is characterized by setting better heat conduction characteristics than those in the direction perpendicular to the two.

More preferably, a ferromagnetic substance is used as the substance. In this case, a magnetic field is applied in the manufacturing process C2 of an ink sheet mixed with an ink ferromagnetic material, and columns of ferromagnetic material aggregated in a columnar shape in a direction perpendicular to the surface of the ink are formed in the ink. .

〔Effect of the invention〕

According to this invention, the heat applied to the ink carrier is not transmitted in the direction perpendicular to the ink transfer direction, but most of it is transmitted in the ink transfer direction≦2, so ink transfer can be performed more reliably and beautifully. .

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail with reference to the drawings. 1st
The figure is an explanatory diagram of an ink sheet manufacturing process for embodying the present invention. Figure Il & 1ta) shows the base film immediately after the ink (282) has been applied with a solvent, and is not a commonly used ink dissolving solution, but an ink dissolving solution (5
) C binary magnetic material (3) is used which is dispersed and contained therein.

Figure 1 (b) 4 shows the state in which the switch (8) for flowing current from the whetstone # (9) into the magnetic field applying device is turned on.
This is two indications. The switch for applying the magnetic field at 9A must be on at least until the solvent evaporates and the vapor (6) (2) completely disappears.

Meanwhile, the ferromagnetic material is forcibly aligned with the magnetic flux (I1127, continuing the columnar arrangement as shown in Fig. 1+c). This figure shows the completed state of ink sheet (2) consisting of ink (4) that has solidified.

The structure of this ink sheet (1) corresponds to the present invention, and the manufacturing method may be different from the above-mentioned method using a solvent, for example, by applying it in a hot molten state and cooling it while applying a magnetic field. do not have. Further, the ferromagnetic material does not need to be in the form of fine particles; a material that is originally acicular is more effective since it has strong mechanical strength in the longitudinal direction. This corresponds to claim 2.1 For example, r-7 elite, which is famous as a recording medium for perpendicular magnetic recording, is generally C;
0.5 μm.

It is said that it is a needle-shaped ferromagnetic material with a ratio of approximately 521 of 0.02 to 0.1 μrn in the trrm direction, and can be manufactured with a length of 1 μm or more depending on the manufacturing process.

Figure 2, Figure 1c, is a diagram for explaining the effect of the present invention in comparison with a conventional example, where Figure 2 is the conventional example when the amount of heat generated is too low, Figure 3 is the conventional example when the amount of calorific value is too much, and Figure 4 respectively indicate the effects of the present invention. In both figures, lal is the state before recording, (b
) shows the state during recording, and (C) shows the state after recording. As can be seen in Fig. 2 (1cI) and Fig. 3 (lal), the conventional ink sheet for thermal transfer has a structure consisting of a simple ink and a base film. Fig. 2 (b)
), Fig. 3 ibl is shown on the thermal head substrate (2) (arranged in a near-array, and individually digitized) while being sandwiched between the nib platen roller and the thermal head 4 and applying pressure. The heat generated by the heating element can control the amount of heat that can cause the ink to melt into a hailstorm.

If the M% density is less than the appropriate value, the transfer will be unstable as shown in the transferred ink in Figure 2, 1cI, so the shape of the recorded dot will include random irregularities and the area of 1 pixel. Also, there are large variations and large recording noise is generated. This tendency is particularly remarkable for recording paper with a smoothness of 300 seconds or less.

Furthermore, if the amount of heat generated is greater than the appropriate value, as shown in Figure 3 ICI, the shape of the transferred ink vI and the print dots become too large, causing various types of image quality deterioration. Conventional problems have been that the appropriate range for the calorific value between these two is narrow, and that the appropriate range fluctuates greatly depending on the temperature condition, and in some cases, the appropriate range disappears. Ta.

The ink sheet according to the present invention (-) is as shown in Fig. 4:a),
It differs from the conventional method in that the ink contains a columnar forced magnetic body @. Since the longitudinal direction of this columnar ferromagnetic material is perpendicular to the heating element and the recording paper, the following special effects occur. In other words, one is that it can transport a large amount of heat in a short period of time, the other is that it can transport a large amount of heat in a short period of time, and the other is that it is difficult to transport heat in the @ plane direction. .

In other words, it has anisotropic heat conduction properties and fast heat transfer properties in the conduction direction. Therefore, when using such an ink sheet, the ink is sufficiently melted and the recording dots do not spread beyond the area of the heating element, so the appropriate range of heat generation to obtain good image quality is widened to non-N. You will be able to take it. This situation is shown in Figure 4 (tbl) and (C1).Furthermore, when the ink melts under pressure with the recording paper, a hard needle-like substance forms. Another important effect is that a phenomenon in which two Cs stick together in the fibers of the recording paper occurs, and this phenomenon increases the adhesion force.

This situation is shown in FIG. 4(C).

As described above, the present invention utilizes the above-mentioned three functions to improve the recording quality of thermal transfer recording (-) which is even better than that of the conventional method.

As explained above, when the ink carrier of this embodiment is used, columns of magnetic material are formed in the ink in the direction perpendicular to the first side of the recording paper, the front side of the ink sheet parallel to it, the back side, the interface between the ink and the base, etc. However, in general, ferromagnetic materials have a much higher thermal conductivity than the ink material (knee), so they give anisotropic thermal conductivity that is small in the plane direction and large in the vertical direction. It is possible to achieve thermal transfer recording in which the recording dots are less likely to spread in the plane direction, making it possible to record with better image quality than before.

In addition, according to this ink carrier, the ferromagnetic pillars formed perpendicular to the ink surface within the ink are made of a harder material than the ink material, so they are compatible with the recording paper and do not absorb heat when pressed from the platen. When added, it acts as a needle between the paper fibers, strengthening the adhesion between the ink and the recording paper.

Therefore, by the action of this needle, thermal transfer recording with improved transferability can be realized, and recording with better image quality than before can be achieved.

With this ink carrier, it is possible to create an ink sheet that has great thermal conductivity in the direction perpendicular to the ink surface, making it possible to efficiently transfer heat only in a specific direction and to transfer heat quickly. This enables thermal transfer recording that is faster and uses less power than conventional methods.

Of course, in this embodiment, only the ink material constituting the ink sheet contains a ferromagnetic material, so if a magnetic field is applied from the back side of the recording paper on the side opposite to the side in contact with the ink sheet 4, during recording ( : It is clear that magnetic attraction is effective in improving the transfer performance.

[Other embodiments of the invention]

Although two embodiments C of this invention have been described above, this invention is not limited to one or more embodiments.

For example, a substance that embodies thermal anisotropy may be any substance that has anisotropic dispersion characteristics, and even if it does not necessarily satisfy this property, a substance that has an acicular crystal structure may be mixed in. The same objective is achieved from the viewpoint of good ink transfer even if the ink is mixed.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the manufacturing process of an ink sheet according to one embodiment, Fig. 42 is an explanatory diagram of a conventional example when the calorific value is excessive, Fig. s3 is an explanatory diagram of the conventional example when the calorific value is excessive, and Fig. 4 is an explanatory diagram of the conventional example when the calorific value is excessive. FIG. 3 is a detailed explanatory diagram of the invention. 1... Ink sheet Beauty... Recording paper 2... Base film 4... Ink sheet 3... Ferromagnetic material
n...Columnar ferromagnetic material 4...Ink
Z3-... Ink 5... Ink dissolving liquid Mu...
・Base film 6... No steam... Thermal head 7... Magnetic field application device... Heating element 8... Swing f Z7... Thermal head board 9...
Magnetic source 4... Ink in a thermally molten state 10...
・Magnetic flux 4...Transferred ink agent
Patent Attorney Kensuke Chika (and 1 other person)＼ η

Claims (2)

[Claims] (1) An ink carrier that is composed of ink and a holding member that supports the ink, and is used to transfer and record the ink onto a recording medium by heat applied to the ink,
A substance having anisotropic dispersion properties is mixed into either the ink or the holding member so that the heat conduction properties along the transfer direction are better than the heat conduction properties in a direction perpendicular to the transfer direction. An ink carrier characterized by comprising: (2) The ink carrier according to claim 1, wherein the substance having anisotropic dispersion characteristics is made of a ferromagnetic substance.