JPH07227986A - Inclined surface type thermal head substrate and method of manufacturing the same - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve heat dissipation and thermal response, to make the surface of the glaze layer smooth and to prevent disconnection in the wiring layer, enabling high-speed and high-quality printing. [Structure] The thermal head substrate is a ceramic substrate 13
And a glass glaze layer 17 formed only on the flat inclined surface 13b. The inclined surface 13b is formed at a line of intersection between one of the main surfaces 13a, 13a facing each other and the end surface. The syringe 2 in which the ceramic substrate 13 is arranged so that the inclined surface 13b is horizontal and which has an injection needle 26a having a needle tip with an inner diameter equal to or smaller than the width of the inclined surface
6 is filled with the glass paste 32. The needle tip of the injection needle is arranged toward the center of the inclined surface, and the ceramic substrate 13 is moved in the longitudinal direction of the ceramic substrate while ejecting the glass paste from the injection needle at a predetermined pressure, so that the glass paste is only applied to the inclined surface. The coating is dried, and baked to form the glass glaze layer 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal head substrate for a thermal transfer printer. More specifically, the present invention relates to an inclined surface type thermal head substrate in which a glass glaze layer is formed on an inclined surface of a ceramic substrate, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Heretofore, an inclined surface type thermal head as shown in FIGS. 6 and 7 has been proposed in order to enable good printing even on a rough printing paper having large unevenness (Japanese Patent Laid-Open No. Sho 6-187). 63-153165). In the thermal head 1, the heating resistor 2 is provided on the inclined surface 3b formed between the main surface 3a and the end surface 3c of the ceramic substrate 3. In this thermal head 1, the heating resistor 2 provided on the inclined surface 3b
Comes into sliding contact with the printing paper 5 supported by the platen 4 via the thermal transfer ink ribbon 6, and at the same time, the thermal head 1 moves in one direction of the arrow A, so that the thermal head 1
The heat generating resistor 2 selectively generates heat in a predetermined pattern, and the thermal transfer ink is transferred from the ribbon 6 to the printing paper 5 to perform desired printing.

Since the printing pressure of this inclined surface type thermal head can be made larger than that of the flat type thermal head, it is possible to perform printing without blur even on hard paper or paper having a rough surface and excellent printing. Have characteristics. As shown in detail in FIG. 6, in the ceramic substrate 3 that is the main body of the thermal head 1, the glass glaze layer 7 is formed over one of the main surfaces 3a, the inclined surface 3b, and the end surface 3c. The heating resistor 2 is formed on the inclined surface 3b via the undercoat layer 8, and the wiring layer 9 connected to the resistor 2 is formed on the surface of the glass glaze layer on the main surface 3a and the end surface 3b. Reference numeral 10 is a protective film that covers the heating resistor 2.

[0004]

However, in the conventional inclined surface type thermal head shown in FIG. 6, the glass glaze layer 7 having both the heat storage function and the heat dissipation function has one main surface 3a, inclined surface 3b and end surface 3c. Since it exists widely, it has the following three drawbacks. First, the heat generated from the heat-generating resistor is difficult to dissipate to the outside, which is not suitable for high-speed printing as a thermal head, and the intersection of the main surface 3a and the inclined surface 3b and the intersection of the inclined surface 3b and the end surface 3c. Then, glaze layer 7
The thickness of the glaze layer is likely to be thin and the intersecting line portion may be exposed. Therefore, it is necessary to form the glaze layer as a whole thicker than that of an end surface type thermal head having no inclined surface. As shown in FIG. 5, in the glass glaze layer 7 of the conventional inclined surface type thermal head substrate, a thick portion a of 150 to 200 μm is locally formed.
May occur, which results in poor thermal response and is also disadvantageous for high-speed printing. Further, when the glaze layer 7 on the inclined surface 3b is thinned, unevenness or a step P is likely to occur on the surface of the glaze layer 7, and when the wiring layer 9 (FIG. 6) is provided, the wiring layer 9 is broken. It happened.

An object of the present invention is to improve the heat dissipation and the thermal responsiveness, the surface of the glaze layer is smooth and the wiring layer is not easily broken, and the inclined surface type thermal printing that enables high-speed and high-quality printing is provided. It is to provide a substrate for a head and a method for manufacturing the same.

[0006]

As shown in FIG. 1, an inclined surface type thermal head substrate of the present invention comprises a flat plate, and a pair of main surfaces 13a, 13a facing each other of the flat plate.
And the flat end face 13c of the flat plate end and one main face 1
3a and a ceramic substrate 13 having a flat inclined surface 13b formed at the intersection of the end surface 13c, and the inclined surface 13
and a glass glaze layer 17 formed only on b.
Here, the thickness a of the glaze layer 17 is preferably in the range of 10 to 50 μm, and more preferably in the range of 20 to 30 μm. If the thickness a is less than 10 μm, the heat storage effect is poor, and if it exceeds 50 μm, the heat dissipation becomes insufficient. The width t of the inclined surface 3b is preferably in the range of 0.15 to 0.8 mm, and more preferably in the range of 0.2 to 0.6 mm. If the width t is less than 0.15 mm, the printing pressure is too strong, and ribbon problems are likely to occur when the thermal head moves. If it exceeds 0.8 mm, the contact area of the thermal head becomes too large and the adhesion between the ink ribbon and the printing paper becomes poor. The angle θ formed by the inclined surface 3b with respect to the one main surface 3a is preferably in the range of 10 to 80 degrees, and more preferably in the range of 20 to 50 degrees. If θ is outside the range of 10 to 80 degrees, the printing pressure is too strong, and ribbon troubles are likely to occur when the thermal head moves.

As shown in FIGS. 3 and 4, the method of manufacturing the inclined surface type thermal head substrate is composed of a flat plate, and a pair of main surfaces 13a, 13a facing each other of the flat plate and a flat end portion of the flat plate. A flat inclined surface 13b is formed at the intersection of one main surface 13a of the ceramic substrate 13 having the end surface 13c and the end surface 13c, and the ceramic substrate 13 is arranged so that the inclined surface 13b is horizontal. A glass paste 32 is filled in a syringe 26 having an injection needle 26a having an inner diameter equal to or smaller than the width of the inclined surface 13b, and the needle tip of this injection needle 26a is directed toward the center of the inclined surface 13b. The ceramic substrate 1 is placed and the glass paste 32 in the syringe is injected from the injection needle 26a at a predetermined pressure.
3 or the injection needle 26a is moved in the longitudinal direction of the ceramic substrate 13 to apply the glass paste 32 only to the inclined surface 13b, and the applied glass paste 32 is dried and baked to form the glass glaze layer 17.

[0008]

Unlike the conventional thermal head substrate shown in FIG. 5, the glass glaze layer 7 is not formed over the main surface 3a, the inclined surface 3b and the end surface 3c, and the glass glaze is formed only on the inclined surface 13b as shown in FIG. In order to form the layer 17, the heating resistor 1 is formed on the inclined surface 13b as shown in FIG.
When 2 is formed to form the thermal head 15, the heat of the resistor 12 is sufficiently dissipated from the main surface 13a and the end surface 13c. Even if the glaze layer 17 is thinned to about 10 to 50 μm, the main surface 13a adjacent to the glaze layer 17 on the inclined surface
Also, the connection with the end face 13c is smooth, and a step is unlikely to occur. Further, the surface of the glaze layer 17 on the inclined surface does not have irregularities or steps, and the wiring layer 19 is less likely to be disconnected. As a result, it is possible to print with high quality and high speed with excellent heat dissipation and thermal response.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings together with comparative examples. <Example> As shown in FIGS. 3 and 4, a length of 200 m
A ceramic substrate 13 composed of a flat plate having an alumina content of 96% by weight and having a width of 10 mm and a width of 10 mm was prepared. A flat inclined surface 13b was formed by grinding at a line of intersection between one of the pair of main surfaces 13a, 13a facing each other of the substrate 13 and the flat end surface 13c of the flat plate end portion. Twenty ceramic substrates 13 were prepared in which the angle θ formed by the inclined surface 13b and the main surface 13a and the width t were changed as shown in Table 1.

[0010]

[Table 1]

The ceramic substrate 13 is sandwiched between the fixtures 21 and 22 so that the inclined surface 13b is horizontal, and the screw 23 is provided.
Is tightened and retained. That is, the fixture 21 has almost the same length as the substrate 13, and is welded to a pair of bosses 21b (only one of which is shown in FIG. 4) slidably fitted with the guide bar 24 via the arm 21a. . The fixture 22 is the substrate 13
Are provided so as to fix both ends in the longitudinal direction, and the base ends thereof are welded to a pair of bosses 22 a screwed to the threaded bar 25. The guide bar 24 and the threaded bar 25 are provided in parallel to each other, and the threaded bar 25 is rotatably attached in the direction of arrow B at a predetermined speed by a driving means (not shown). In this example, the rotation of the bar 25 causes the fixture 2
1, 22 and the ceramic substrate 13 can move in the direction of arrow C at a constant speed of 10 mm / sec.

The syringe 26 is vertically fixed with the needle tip of the injection needle 26a directed toward the center of the inclined surface 13b. That is, the inner diameter of the needle tip of the syringe 26 is equal to or smaller than the width t of the inclined surface 13b, and the body portion 26b thereof is held by the pair of holders 27 and attached to the bracket 29 fixed to the base 28. In this example, the injection needle 26a having a needle diameter of 0.2 mm is selected. An air hose 31 is connected to the upper portion 26c of the syringe 26. Air of a predetermined pressure is supplied from an air source (not shown) through the air hose 31. The inside of the syringe 26 is filled with a predetermined amount of glass paste 32 in advance. This glass paste 32 is 5
It has a viscosity in the range of 000 to 20,000 CPS (centipoise), and has a viscosity of 10,000 CPS in this example, and is prepared by mixing glass powder [GA-1, manufactured by Nippon Electric Glass Co., Ltd.], ethyl cellulose and terepionel. Was done.

Next, a method of using the glass paste coating device having such a structure will be described. First, 20 ceramic substrates 13 were attached one by one using the attachments 21 and 22. Air hose 31 to syringe 26 for each ceramic substrate
The air pressure supplied to the needle is changed in four steps, and the needle 26 of the syringe 26 is
The injection amount of the glass paste 32 from a was adjusted. The bar 25 with screw is rotated at a predetermined speed for each injection amount to move the ceramic substrate 13 along the guide bar 24 by 10 m.
The glass paste 32 was applied to the inclined surface 13b by moving at a constant speed of m / sec. After coating, the ceramic substrate 13 was removed from the fixtures 21 and 22 and dried at 150 ° C. for 1 minute. After drying, the applied glass paste 32 is baked at 950 ° C. for 60 minutes, and the glass glaze layer 17 is formed on the inclined surface 13b.
Was formed. Table 1 shows the thickness a of the glass glaze layer 17 for each of the 20 ceramic substrates.

<Comparative Example> 20 ceramic substrates having the same shape and size as those of the example were prepared, and a glass paste was applied to these ceramic substrates over the main surface 3a, the inclined surface 3b and the end surface 3c as shown in FIG. did. The coating amount was such that the thickness a of the glaze layer 7 on the end face 3c was the same as in Table 1, and a thermal head substrate was produced.

A thermal head was produced from each of the 20 thermal head substrates obtained in the above-described examples and comparative examples, and the produced thermal head was first examined for disconnection and then subjected to a printing test. went. That is, as shown in FIG. 2 (or FIG. 6), the undercoat layer 18 (or 8), the heating resistor 12 (or 2), the wiring layer 19 (or 9), and the protective layer 20 (or 10) are respectively attached to the thermal head. The thermal head 15 and the thermal head 1 of 20 types were obtained for each of the example and the comparative example. First, the presence or absence of disconnection of the wiring of these thermal heads 15 and 1 was examined. The results are shown in Table 2. As is clear from Table 2, in the thermal head using the substrate of the example, the wiring was not broken except for the glaze layer having a thickness of 5 μm. On the other hand, in the thermal head using the substrate of the comparative example, the wiring was broken not only when the thickness of the glaze layer was 5 μm but also when it was 10 μm.

Further, 19 thermal heads 15 of the embodiment and 18 thermal heads 1 of the comparative example in which no wire breakage was observed were individually mounted on the thermal transfer printer shown in FIG. 7, and the paper surface was rough. Average printing speed on plain paper 100 mm /
Printing was performed in seconds, and the presence or absence of print fading and the presence or absence of ink ribbon trouble were examined. The results are shown in Table 3. As is clear from Table 3, the thermal heads of the examples had no print fading, whereas the thermal heads of the comparative examples showed print fading for No. 3 and No. 6. Ink ribbon troubles are No. 7, No. 7 in both Examples and Comparative Examples.
Seen in 13 and No. 14.

[0017]

[Table 2]

[0018]

[Table 3]

Although the ceramic substrate is moved at a constant speed in the above example, the ceramic substrate may be fixed and the syringe may be moved at a constant speed.
Further, the injection amount from the syringe may be made constant, and the moving speed may be made variable to adjust the application amount of the glass paste.

[0020]

As described above, according to the thermal head substrate of the present invention, unlike the conventional case, the glass glaze layer is formed only on the inclined surface, so that the heating head is formed on the inclined surface. When set to, the heat of the resistor is sufficiently dissipated from the main surface and the end surface. In addition, the glaze layer is 10
Even if the thickness is reduced to about 50 μm, the connection between the main surface and the end surface adjacent to the glaze layer on the inclined surface is smooth, a step is unlikely to occur, and the wiring layer is less likely to be disconnected. as a result,
The thermal head using the substrate of the present invention is excellent in heat dissipation and thermal response, and can print with high quality and high speed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an inclined surface type thermal head substrate of the present invention.

FIG. 2 is a sectional view of a thermal head using the substrate.

FIG. 3 is a cross-sectional view showing the manufacture of the inclined surface type thermal head substrate of the present invention.

FIG. 4 is a perspective view showing the manufacture of the inclined surface type thermal head substrate of the present invention.

FIG. 5 is a cross-sectional view of a conventional inclined surface type thermal head substrate.

FIG. 6 is a cross-sectional view of a thermal head using the substrate.

FIG. 7 is a diagram showing a usage state of an inclined surface type thermal head.

[Explanation of symbols]

 13 ceramic substrate 13a main surface 13b inclined surface 13c end surface 15 thermal head 17 glass glaze layer 26 syringe 26a injection needle 32 glass paste

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ryoji Imaizumi 2270 Yokose, Yokose-cho, Chichibu-gun, Saitama Sanryo Materials Co., Ltd. Ceramics Laboratory

Claims (2)

[Claims] 1. A pair of main surfaces (13a, 13a) of a flat plate facing each other, and a flat end surface (13c) of the flat plate end portion.
A ceramic substrate (13) having a flat inclined surface (13b) formed at the intersection of the one main surface (13a) and the end surface (13c), and only the inclined surface (13b). Formed glass glaze layer (1
7) An inclined surface type thermal head substrate having and. 2. The one main surface of a ceramic substrate (13) comprising a flat plate and having a pair of main surfaces (13a, 13a) facing each other of the flat plate and a flat end surface (13c) of the flat plate end portion. (13a) and a flat inclined surface (13b) is formed at the intersection of the end surface (13c), the ceramic substrate (13) is arranged so that the inclined surface (13b) is horizontal, A glass paste (32) is filled in a syringe (26) having an injection needle (26a) having an inner diameter equal to or smaller than the width of the surface (13b), and the needle tip of the injection needle (26a). Is placed toward the center of the inclined surface (13b), the glass paste (3 in the syringe from the injection needle (26a).
While injecting 2) at a predetermined pressure, the ceramic substrate (13)
Alternatively, by moving the injection needle (26a) in the longitudinal direction of the ceramic substrate (13), the glass paste (32) is applied only to the inclined surface (13b), and the applied glass paste (32) is dried and baked. A method for manufacturing an inclined surface type thermal head substrate for forming a glass glaze layer (17).