JPH0811468B2 - Thermal transfer ink medium - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer ink medium having an ink for transferring to a recording paper in a thermal transfer recording apparatus, and more particularly to thermal transfer in which ink is repeatedly applied by an ink applying mechanism provided in the thermal transfer recording apparatus. Regarding the ink medium.

[0002]

2. Description of the Related Art As a conventional thermal transfer ink medium, a heat-meltable ink that is solid at room temperature and has the property of increasing its fluidity when heated is applied to a large plain film by a coating device to have a thickness of about several μm. There was a type in which it was applied to a thickness of 10 mm, cut to a desired size and used as a thermal transfer ink medium in a thermal transfer recording apparatus.

However, such a thermal transfer ink medium can generally be used only once for recording. Therefore, in the thermal transfer recording apparatus using such a thermal transfer ink medium, the thermal transfer ink medium having the same length as the recording paper is consumed, and there is a disadvantage that a large amount of waste occurs and the running cost increases. .

Therefore, recently, in order to eliminate such waste of the thermal transfer ink medium, a mechanism for forming a thermal transfer ink medium of an appropriate length in an endless shape and applying a heat-melting ink to the endless thermal transfer ink medium is provided. A reproduction type thermal transfer ink medium has been proposed which is incorporated in a thermal transfer recording apparatus and is capable of repeatedly applying and recording ink in the thermal transfer recording apparatus.

In an ink application mechanism provided in a thermal transfer recording apparatus for applying ink to such a thermal transfer ink medium, a part of a horizontally arranged ink replenishing roller is heated and melted in an ink containing section. Soak in
The thermal transfer ink medium is stretched so as to come into contact with the other parts of the ink replenishing roller, and the ink replenishing roller is rotated together with the feeding of the thermal transfer ink medium to temporarily replenish the ink in the ink containing portion. It is attached to the surface of the roller and is further attached to the thermal transfer ink medium.

According to the above-mentioned ink application mechanism, the ink is applied over the entire width of the thermal transfer ink medium, but since the printing area of the thermal transfer recording apparatus is limited, the transfer of the ink reaches the entire width of the thermal transfer ink medium. As a result, the ink that is repeatedly applied is accumulated on both sides of the thermal transfer ink medium in which the ink is not transferred to the recording paper, and there is a problem that the recording paper is soiled. In order to solve such a problem, the wettability and adhesion of the surface of the ink area to which the ink of the thermal transfer ink medium is to be applied to the ink is improved, and the surfaces of both sides of the thermal transfer ink medium that are parts other than the ink area are formed. There is a method in which the ink area on the thermal transfer ink medium is defined by lowering the wettability and the adhesiveness with the ink (JP-A 61-41562).

[0007]

As described above, even if the adhesion of the surface of the thermal transfer ink medium other than the ink area to the ink is reduced, the adhesion of the ink to the area other than the ink area is completely prevented. However, when the thermal transfer recording medium travels on the ink replenishing roller for the thermal transfer recording device, ink adheres to a portion other than the ink region of the thermal transfer recording medium.

Further, as shown in FIG. 4, which will be described later, even if the ink replenishing roller 11 does not supply ink to both sides of the thermal transfer ink medium other than the ink region, the thermal transfer ink medium is between the rollers in the thermal transfer recording apparatus. When being stretched and run, the ink is skewed and gradually shifted in the direction perpendicular to the running direction, that is, in the width direction, and ink is applied to both sides of the thermal transfer ink medium other than the ink region.

Further, when the ink is attached to the thermal transfer ink medium by static electricity or the like, heat is applied in the ink application mechanism section or the like, and as a result, the ink is melted and adhered to both side portions of the thermal transfer ink medium, the wettability with the ink. In addition, since the adhesion is poor, the ink is in a raised state, and there are drawbacks such that the recording paper is soiled by rubbing against the recording paper, and the device is soiled due to ink drop.

It is an object of the present invention to provide a thermal transfer ink medium which enables stable image quality in a thermal transfer recording apparatus having an ink application mechanism.

[0011]

In the thermal transfer ink medium of the present invention, the ink layer should be formed in a thermal transfer ink medium in which ink is applied by an ink applying mechanism provided in a thermal transfer recording device to form an ink layer. It is characterized in that an ink absorbing portion is provided in a portion other than the ink region.

[0012]

According to the thermal transfer ink medium of the present invention, the ink applied to the portion other than the ink area is absorbed in the ink absorbing portion, so that the portion other than the ink area is applied by the ink applying mechanism and the recording paper is used at the time of printing. Ink swelling due to the ink not transferred to the ink and ink around the back surface of the thermal transfer ink medium are prevented.

[0013]

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of a portion of a thermal transfer ink medium according to one embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view showing the thermal transfer ink medium shown in FIG. 1 in the thickness direction. FIG. 3 is a sectional view of a thermal transfer recording apparatus using the thermal transfer ink medium shown in FIG. FIG. 4 is an enlarged perspective view of part A of FIG.

In the thermal transfer ink medium 1 shown in FIG. 1, carbon having a particle diameter of several μm is used as a thermally conductive substance in an amount of 5 to 5% with respect to a polymer component such as aramid or polyimide.
It is a film formed by adding 50 wt% to a thickness of 10 to 20 μm. The surface resistance of the created thermal transfer ink medium 1 is 0.3 to 1 kΩ. Next, as shown in FIG. 2, both sides of the thermal transfer ink medium 1 other than the ink region 18 to which the heat-meltable ink 16 is applied are chemically treated to form pores having a pore diameter of 1 to 1000 μm and a depth of 5 to 10 μm. The ink absorbing portion 2 including the quality portion was molded. The width of the ink area 18 is almost the same as the maximum printing area in the thermal transfer recording device.

The thermal transfer recording apparatus shown in FIG. 3 includes a thermal head 4, a platen roller 3, a paper feed system including a pick roller 17 for feeding the recording paper 10, a feed roller 6 for feeding the thermal transfer ink medium 1. A tension roller 8 for applying tension to the thermal transfer ink medium 1,
A film traveling system including a guide roller 9 and a skew feeding correction mechanism 7 for the thermal transfer ink medium 1, an ink containing portion 15 containing a heat-meltable ink 16, a heater 14, an ink replenishing roller 11, a sub roller 12, Sub ink member 1
3 and an ink application mechanism section.

The endless thermal transfer ink medium 1 is shown in FIG.
The thermal head 4, the skew feed correcting mechanism 7, and the rollers are set inside the apparatus as shown in FIG. The thermal transfer ink medium 1 is conveyed by the platen roller 3 and the feed roller 6, and is brought into close contact with and pressed against the recording paper 10 by the thermal head 4 and the platen roller 3. The tension roller 8 gives a constant tension to the thermal transfer ink medium 1.
Further, when the endless thermal transfer ink medium 1 is driven by the roller, the thermal transfer ink medium 1 may be affected by a dimensional error of a driving mechanism, a dimensional error of the thermal transfer ink medium 1, or uneven frictional resistance acting on the thermal transfer ink medium 1. Although it gradually shifts (skew) in a direction (width direction) perpendicular to the traveling direction, the skew correction mechanism 7 can limit the skew amount within 1 to 2 mm. The skew feeding correction mechanism 7 functions to tilt the roller around which the thermal transfer ink medium 1 is stretched according to the shift of the thermal transfer ink medium 1 in the width direction to restore the shift.

The ink containing portion 15 is made of a metal such as aluminum having good heat conductivity, and contains the heat-meltable ink 16 therein. The heat-meltable ink 16 is provided on the bottom surface of the ink container 15.
A heater 14 that maintains a certain temperature slightly higher than the melting point of is fixed and melts the heat-meltable ink 16 in the ink container 15 in a liquid state. The ink replenishing roller 11 is a roller made of stainless steel or aluminum (a tube having a wall thickness of 1 to 2 mm) whose surface is roughened by sandblasting or knurling. The ink replenishing roller 11 is driven by a gear connected to the guide roller 9 and rotates in the same direction and at the same peripheral speed as the thermal transfer ink medium 1. Immediately after the ink replenishing roller 11, a non-rotating sub ink member 13 is provided in front of the guide roller 9.

Next, the operation of the thermal transfer recording apparatus shown in FIG. 3 will be described. The pick roller 17 is rotated by a gear (not shown) connected from the motor 5 and sends the recording paper 10 to the platen roller 3. Then, the thermal head 4 receives a drive signal from a control circuit (not shown), Part of the thermal transfer ink medium 1 is heated by the heat of the head 4, and the melted heat-meltable ink 16 is transferred to the recording paper 10.

On the other hand, the thermal transfer ink medium 1 is conveyed to the ink applying mechanism through the thermal head 4. In this ink application mechanism, the thermal transfer ink medium 1 is conveyed in the direction of the arrow shown in FIG. 4, and the heat-meltable ink 16 is supplied to one surface of the thermal transfer ink medium 1 from the ink replenishing roller 11. The ink layer on the surface of the thermal transfer ink medium 1 supplied by the ink replenishing roller 11 has unevenness in the transferred ink layer because the surface of the ink replenishing roller 11 is grainy or knurled. Therefore, the heat-meltable ink 16 is formed of a round bar (made of stainless steel or aluminum haku) having a smooth flat surface before it is solidified, a wire-wound bar, or a lathe or a bar having a predetermined groove formed by chemical treatment or the like. A smooth ink layer is formed on the thermal transfer ink medium 1 by rubbing the surface of the ink layer with the sub-ink member 13 (which is also controlled to have a temperature equal to or higher than the melting point of the hot-melt ink 16).

The length of the ink replenishing roller 11 together with the ink area 18 of the thermal transfer ink medium 1 is substantially the same as the width of the maximum print area of the thermal transfer recording apparatus, and is located corresponding to this maximum print area. Sub-rollers 12 that extend to both ends of the ink replenishing roller 11 and that do not rotate coaxially with the same diameter as the ink replenishing roller 11 are provided and receive both sides of the thermal transfer ink medium 1 to extend the thermal transfer ink medium 1 in the entire width direction. It is stretched uniformly without any creases, and ink is not supplied to both sides.

At both end portions other than the portion corresponding to the maximum printing area of the sub ink member 13, there are provided portions having a smooth surface having a width similar to that of the sub roller 12. Therefore, the heat-soluble ink 16 applied to the ink region 18 of the thermal transfer ink medium 1 slightly sticks out of the ink region 18 by the sub-ink member 13 and adheres to the ink absorbing portions 2 on both sides. Further, the ink is applied to the ink absorbing portion 2 due to the skew of the thermal transfer ink medium 1.

However, since the melted ink 16 applied to the ink absorbing portion 2 is absorbed in the porous layer, the ink swelling on the surface of the ink absorbing portion 2 and the ink around the back surface of the thermal transfer ink medium 1 are prevented. Can be prevented.

The hot-melt ink 16 used in this embodiment is used.
Is a black ink having a melting point of 70 to 75 ° C. and a viscosity of 50 to 1000 cps (90 ° C.), which is composed of pigment, carnauba wax, ester wax, oil and the like.

The ink absorbing part is not only the one in which the thermal transfer ink medium is chemically treated to provide the porous part as in the present embodiment, but also the one in which the tape formed in advance is attached to the thermal transfer ink medium. Alternatively, a tape obtained by assembling fine fibers may be attached to the thermal transfer ink medium.

Further, in a thermal transfer recording apparatus which prints only on a specific dedicated form, depending on the form of the form, printing is not performed at all in the central portion in the width direction of the thermal transfer ink medium and the ink is transferred to the recording paper. When there is a portion that is not covered, an ink absorbing portion may be provided at the center of such a thermal transfer ink medium.

[0027]

As described above, the present invention is a thermal transfer ink medium having a heat-meltable ink layer for transferring a portion locally heated by a thermal head of a thermal transfer recording apparatus onto a recording paper. Although the ink layer is formed by ink application by the ink application mechanism provided in the thermal transfer recording apparatus, the ink corresponding to the maximum print area of the thermal transfer recording apparatus is applied to both side parts other than the ink area to be applied. By providing the absorbing portion, it is possible to prevent ink bulge on both sides of the thermal transfer ink medium and ink around to the back side, and without contaminating the recording paper and the thermal transfer recording device.
It is possible to obtain high-quality recording and provide highly reliable thermal transfer recording.

[Brief description of drawings]

FIG. 1 is a perspective view showing a part of a thermal transfer ink medium according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the thermal transfer ink medium shown in FIG.

3 is a cross-sectional view of a thermal transfer recording device using the thermal transfer ink medium shown in FIG.

FIG. 4 is an enlarged perspective view of part A of FIG.

[Explanation of symbols]

 1 Thermal Transfer Ink Medium 2 Ink Absorbing Section 3 Platen Roller 4 Thermal Head 5 Motor 6 Feed Roller 7 Skew Correction Mechanism 8 Tension Roller 9 Guide Roller 10 Recording Paper 11 Ink Replenishing Member 12 Sub Roller 13 Sub Ink Member 14 Heater 15 Ink Storage Section 16 Heat Melt ink 17 Pick roller

Claims (6)

[Claims] 1. In a thermal transfer ink medium in which ink is applied by an ink applying mechanism provided in a thermal transfer recording device to form an ink layer, an ink absorbing portion is provided in a portion other than an ink region where the ink layer is to be formed. A thermal transfer ink medium characterized by the above. 2. The thermal transfer ink medium according to claim 1, wherein the ink absorbing portion comprises a porous portion. 3. The thermal transfer ink medium according to claim 2, wherein the ink absorbing portion comprises a porous portion formed by a chemical treatment. 4. The thermal transfer ink medium according to claim 2, wherein a porous tape is attached to the ink absorbing portion. 5. The thermal transfer ink medium according to claim 1, wherein the ink absorbing portion is a tape to which a fiber aggregate is attached. 6. The thermal transfer ink medium according to claim 1, 2, 3, 4, or 5, wherein ink absorbing portions are provided on both sides.