JPH0221235Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a thermal printing head, and more particularly to the structure of a glaze layer formed as a heat storage layer on an insulating substrate.

<Prior Art> Generally, as shown in the plan view of FIG. 6, a thermal printing head is formed by forming a glaze layer 62 as a heat storage layer on a long insulating substrate original plate 61 along its length. After the heating element 63 is provided on the glaze layer 62 in a state where it is connected to the conductor layer 64, the intermediate part between the substrate original plate 61 and the glaze layer 62 is cut along the cutting line A using a cutting means such as a laser. Thus, a single thermal printing head 65 having a substrate 66 of the required length is manufactured. Of course, the heating element 63 is coated with a wear-resistant layer made of glass, but illustration of the wear-resistant layer is omitted in order to clarify the problems described below. In this way, not only the original board 61 but also
The reason why the glaze layer 62 is also cut is to reduce the number of raised edges of the glaze layer.If the glaze layer is formed by attaching the glaze to the substrate by screen printing, the edges will be cut more than necessary. On the other hand, if the ends are formed by cutting, the ends will not be raised, and the number of raised ends will be reduced accordingly.

<Problems to be solved by the invention> By the way, the glaze layer 62 on the original substrate 61
Conventionally, as shown in the sectional view of FIG. 7A, each part has a constant height and a constant width, and the cut portion 62a also has the same cross-sectional area as the other parts. No particular problem occurs when cutting this cut section 62a with a diamond dicer, but when cutting the cut section 62a with a laser, the glaze in the section melts due to the heating of the laser, as shown in FIG. 7B. The raised portion 62b may be as high as or higher than the heating element 63, and this raised portion 62b may damage the ink ribbon or thermal paper during printing, or may prevent pressure contact between the heating element 63 and the thermal paper, resulting in poor printing. There were drawbacks that had negative effects such as causing

Furthermore, the laser acts on the glaze layer 62 not only when cutting the substrate original plate 61 with a laser, but also when cutting cuts in the substrate original plate 61 with a laser before providing the heating element 63 on the glaze layer 62. Then, a raised portion 62b similar to that described above is generated in the glaze layer, which causes various adverse effects during printing operation.

In view of such conventional problems, it is an object of the present invention to eliminate the formation of protuberances due to melted glaze in the glaze layer, thereby preventing inconveniences such as printing defects and damage to the ink ribbon during printing operations.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the present invention is such that the thickness of the cut portion of each part of the glaze layer where the cutting means such as a laser acts is made smaller than that of other parts. .

<Example> Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

FIG. 1 shows a first embodiment of the present invention.
Figure A is a plan view thereof, and Figure B is a sectional view thereof. In the figure, 1 is a base plate, 3 is a heating element, and 4 is a conductor layer, and these may have the same structure as the conventional one. Therefore, the thickness of the glaze layer 20 is reduced to k at the cutting portion 20a where a cutting means such as a laser acts.
The thickness h of the cut portion 20a is made lower than the film thickness h of other portions, thereby making the cross-sectional area of the cut portion 20a smaller than that of the other portions. Note that the width w of the glaze layer 20 is constant in each part. The original substrate 1 and the glaze layer 20 are cut along cutting line A, thereby producing a thermal printing head body 5 having a substrate of the required length.

If the thickness of the cut portion 20a of the glaze layer 20 is smaller than the other portions, when the laser acts on the cut portion 20a, if the glaze on the cut portion 20a melts due to laser heating, the amount of glaze melted will be small and Because surface tension acts, as shown in the cross-sectional view of FIG. 2, there is hardly any bulge in the cut portion of the glaze layer 20, and even if it does, only a very small bulge 20c is formed. Since it is difficult to completely suppress the swelling of the molten glaze layer, simply making the width of the cut portion 20a of the glaze layer 20 narrower than other portions may still cause the raised portion 20c to be higher than the heating element 3. be. On the other hand, if the thickness of the cut portion 20a of the glaze layer 20 is made small in advance as in this embodiment, the glaze layer 20 can have a raised portion 20c.
Even if it occurs, it will not become higher than the heating element 3, so it is possible to reliably avoid the occurrence of printing defects and the like. In this embodiment as well, a glass wear-resistant layer is coated on the heating element 3, but in order to clearly show the structural features of the present invention, illustration of the wear-resistant layer is omitted. The same holds true for the following examples.

Figure 3 shows the embodiment of Figure 2.
is a plan view thereof, and B is a sectional view thereof. In this embodiment, the width v of the cut portion 22a of the glaze layer 22 is made narrower than the width w of other portions, and the thickness k of the cut portion 22a is made lower than the height h of the other portions.
This makes the cross-sectional area of the cut portion 22a smaller than other portions.

In this second embodiment, not only the film thickness k but also the width v at the cut portion 22a of the glaze layer 22 are made smaller than other parts, so that the laser beam can be used more reliably than in the first embodiment. It is possible to avoid swelling of the glaze layer during cutting.

In each of the above embodiments, each glaze layer 20,
After providing the heating element 3 on 22, the glaze layer 20,
Although the case in which the laser acts on the glaze layers 20 and 22 is shown, the laser acts on the glaze layers 20 and 22 also in the case where cuts are carved with a laser on the surface of the original substrate 1 before providing the heating elements 3 on the glaze layers 20 and 22. do. Even in such a case, the first reason is that almost no swelling occurs at the cut ends of the glaze layers 20 and 22.
This is the same as in the embodiment.

Conventionally, the glaze layer is formed by laminating several layers of glaze by screen printing, but the glaze layer 2 in each of the above embodiments is
0 and 22 are formed by preparing several types of laminated printing patterns and combining these patterns. That is, a pattern P1 having a uniform width at each part as shown in FIG. 4A, a pattern P2 having a narrow width at the cut portion as shown in FIG. Prepare a pattern P3 of C on top of pattern P1 of A.
When laminated, the glaze layer 20 in the first embodiment shown in FIG. 1 is obtained.

Also, pattern P of C is placed on pattern P2 of B.
3, a glaze layer 22 in the second embodiment shown in FIG. 3 is obtained.

<Effects of the invention> As described above, in the present invention, the thickness of the cut portion of the glaze layer is made smaller than the other portions, and even if the laser acts on the cut portion, the molten glaze will not swell significantly. This eliminates various inconveniences that conventionally occur during printing operations due to the ridges caused by the melted glaze reaching a height that exceeds the heating element, such as damage to thermal paper and ink ribbons and poor printing. It doesn't happen.

[Brief explanation of the drawing]

Fig. 1 shows a first embodiment of the present invention, Fig. A is a plan view, Fig. B is a sectional view, Fig. 2 is a sectional view of main parts showing the state after cutting, and Fig. 3 is a second embodiment. Give an example,
Figure A is a plan view, Figure B is a sectional view, Figures 4 A to C
5 is a plan view of a printing pattern for forming a glaze layer, FIG. 5 is a plan view of a conventional thermal printing head, and FIG. 6 is an enlarged sectional view of its main parts. Figure B shows the state after cutting. 1... Substrate original plate, 20, 22... Glaze layer,
20a, 22a... cutting section, 3... heating element, 4...
...conductor layer.

Claims (1)

[Claims for Utility Model Registration] A glaze layer is formed along the length of an insulating original substrate, a heating element connected to a conductive layer is provided on the glaze layer, and the original substrate and glaze layer are connected to each other. In a thermal printing head in which a single thermal printing head having a substrate of a required length is manufactured by cutting with a laser, the film thickness of the cut portion where the laser acts among each portion of the glaze layer is set higher than that of other portions. A thermal printing head characterized by a small setting.