JPH07115479B2 - Method of manufacturing thermal print head - Google Patents

Description

The present invention relates to a method for manufacturing a thermal print head.

(Prior Art) As is well known, in the line type thermal print head,
As shown in FIG. 1, on the surface of a substrate 1 made of ceramic or the like, in addition to a linear heating element 2 and a driving circuit 3 made of an integrated circuit, a common pattern 4 for applying a voltage to the heating element 2 and a heating element. Each of the lead pattern 5 connecting the drive circuit 3 and the drive circuit 3 and the logic pattern 6 around the drive circuit 3 are formed by etching.

By the way, when manufacturing a head of this type using the same drive circuit 3 and the same dot density, a plurality of regions are defined with reference to a region A in which one unit is a pattern forming region of the drive circuit 3. Each pattern is formed on the surface of the substrate 1 so as to be arranged in the lateral direction.

In this case, for the left and right end areas AL and AR,
Since it is necessary to form the common patterns 4 side by side, it is wider than the other regions A by the amount of the common patterns 4.

In the head having such a configuration, there is a case where the same drive circuit is used as described above, the heads have the same dot density and only the print width is different. Such a head may be manufactured by differentiating the number of regions A in the middle, in addition to the regions at the left and right ends.

However, conventionally, a plurality of photomasks corresponding to respective print widths are prepared, and a photomask corresponding to the required print width is selected from the photomasks to form each pattern by etching.

Therefore, according to such a manufacturing method, it is necessary to prepare various kinds of photomasks, and thus the design cost and the manufacturing cost of the photomask are increased, and accordingly, the manufacturing cost of this kind of head is also increased. .

(Problems to be Solved by the Invention) An object of the present invention is to make it possible to manufacture various types of heads having different print widths only by preparing one type of photomask.

(Means for Solving Problems) The present invention provides one pattern formation area for each drive circuit.
A plurality of units are arranged side by side in the lateral direction, and end regions obtained by adding a common pattern forming region to the one unit region are arranged on the left and right ends of the unit and secured on a substrate, and lead patterns and logic patterns are provided in the entire region. , A photomask is used for etching, and a required number of regions are collectively set as one head region, and a common pattern is formed by screen printing for each one of these head regions. It is characterized in that it breaks for each head area.

(Embodiment) An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 2 illustrates a case where the number of pattern formation regions per drive circuit is 11, for example, as shown in FIG. 2C.

On the substrate 1, nine areas A arranged in the lateral direction and end areas AL and AR located at the left and right ends thereof are secured. The heating element 2 is provided over the entire area, and the lead pattern 5 and the logic pattern 6 are further formed by using a photomask.
Are formed by etching. When manufacturing a thick film type head, a heating element is printed after forming a pattern.

In this case, the heating element 2 may be provided after forming each pattern. Further, the common pattern 4 as shown in FIG. 1 may be formed together with each of the above-mentioned patterns.

Next, a case of manufacturing one head in which the number of regions initially required is three will be described. In this case, as shown in FIG. 2A, for example, three areas are secured from the left end of the substrate 1, and the area is extended between the center of the fourth area next to the area and the left end of the substrate 1. , The common pattern 11 is formed by screen printing.

Since the drive circuit is not mounted in the fourth area and is not related to the lead connection, even if the end portion of the common pattern is printed over the pattern in this area, the lead connection is not affected.

In the same manner, the three areas from the fifth area are secured in the same manner, and the common pattern 11 is formed by screen printing over the center of the fourth area to the center of the eighth area. The same applies to the area to the right of this. Actually, all the common patterns 11 may be formed at the same time.

After this, a break is made from the center of the fourth and eighth regions as shown by the chain line. As a result, three heads having three regions can be manufactured.

Next, a case of manufacturing one head in which the required number of regions is 5 will be described. In this case, as shown in FIG. 2B, five areas are secured from the left end of the substrate 1, and the area between the center of the sixth area adjacent to the left end and the left edge of the substrate 1 is extended, The common pattern 12 is formed by screen printing. The same applies to the area to the right of this.

After this, a break is made from the center of the sixth area as shown by the chain line. As a result, two heads having five areas can be manufactured.

When the required number of regions is 11, the common pattern 13 may be formed by screen printing over the left and right ends as shown in FIG. 2C without any division.

As described above, even if a pattern is formed using the same photomask, various types of heads having different print widths can be manufactured.

As shown in the figure, when the pattern 7 for connecting the input / output terminals of the adjacent drive circuits 3 is formed over the respective regions, the common patterns 11, 12 and the like are formed after that.
The common pattern may short the pattern 7.

In order to avoid this, for example, if the pattern 7 is not formed continuously between the adjacent regions and is cut in the middle, the short circuit will not occur. Then, the patterns 7 that require connection later may be connected to each other by wire bonding. Alternatively, an external circuit to be connected later, for example, a flexible wire (FPC) conductor may be used for connection.

Further, in the drawing, the heads arranged in the lateral direction are shown as one stage, but in actual production, this may be produced by patterning multiple stages, for example, three stages at the same time.

(Effects of the Invention) As described in detail above, according to the present invention, various types of heads having different print widths are arbitrarily manufactured from those having a pattern formed by etching using the same photomask. Therefore, it is not necessary to prepare various kinds of photomasks as in the past, which reduces the design cost and manufacturing cost of this kind of head, and also stocks this after etching the pattern. It is also possible to make various heads according to the order received, and thus the delivery time can be greatly shortened.

[Brief description of drawings]

FIG. 1 is a plan view for explaining an embodiment method of the present invention, and FIG. 2 is a plan view showing a common pattern by screen printing. 1 ... Substrate, 2 ... Heating element, 3 ... Drive circuit, 4 ... Common pattern, 5 ... Lead pattern, 6 ... Logic pattern, 11 to 13 ... Common pattern, A ... Region, A
L, AR ... left and right end areas,

Claims (1)

[Claims] 1. A method of manufacturing a thermal print head having a heating element, a driving circuit and various patterns on a surface of a substrate, wherein one pattern forming region for each driving circuit is defined as one unit, and a plurality of units are defined. End areas in which a common pattern forming area is added to the one unit area are arranged side by side in the lateral direction and secured on the substrate, and a heating element is provided over the entire area, and leads are provided in each area. A pattern and a logic pattern are formed by etching using a photomask, and then a number of regions required for one head are collectively formed, and the one unit region is interposed between the combined regions. Into a plurality of 1-head areas, and a common pattern is screen-printed for each of the 1-head areas.
Formed across both ends of the head area, then
A method for manufacturing a thermal print head, characterized in that, for each head region, a break is made from the middle of the one unit region interposed between the regions.