JPH0427947B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Field of Application> The present invention relates to a method of manufacturing a thermal printing head.

<Prior Art> FIG. 1 is a simplified plan view of a conventional thermal printing head. This thermal printing head 1 is of a so-called edge type, and a band-shaped heating resistor 2 is formed along the edge of an insulating substrate 3 in the printing width direction (horizontal direction in FIG. 1). Reference numeral 4 denotes a drive circuit for controlling energization of the heat generating resistor 2, and this drive circuit 4 generates heat via individual energizing electrodes 5 individually connected to the heat generating resistor 2 for each printed dot. The resistor 2 is energized.

Reference numeral 6 denotes a common electrode, and this common electrode 6 extends along the print width direction (horizontal direction in FIG. 1), and further extends from both ends thereof in a direction perpendicular to the print width direction (vertical direction in FIG. 1). The common electrode 6 is connected to the individual current-carrying electrodes 5 via the heating resistor 2.

<Problems to be Solved by the Invention> In such a conventional thermal printing head 1, since the common electrode 6 is formed along the printing width direction closer to the edge of the substrate 3 than the heating resistor 2, the heating resistor body 2
cannot be placed sufficiently close to the edge of the substrate 3, and therefore the edge type feature of being able to immediately see the printed characters cannot be fully utilized.

To deal with this, it has conventionally been proposed to set the direction in which the common electrode is drawn out from the continuous heating element 2 in the same direction as the individual current-carrying electrodes 5, and to provide the common electrode between the individual current-carrying electrodes 5 ( For example, JP-A-58
-Refer to Publication No. 29686). According to this electrode arrangement structure, the continuous heating element 2 can be provided sufficiently close to the edge of the substrate 3.

By the way, in the electrode arrangement structure as proposed above, in order to prevent the common electrode part and the individual current-carrying electrodes from overlapping, it is necessary to interpose an insulating layer between the two electrodes. A common electrode is formed, then an insulating layer is formed to cover a portion of this common electrode, and then individual current-carrying electrodes are formed on the insulating layer.

In this way, in the structure proposed above, among the common electrodes and individual current-carrying electrodes that are arranged in parallel alternately, the common electrode is formed first, and then the individual current-carrying electrodes are formed within the interval between the common electrodes. Since the process of forming the common electrode and the process of forming the current-carrying electrodes are separated, the individual current-carrying electrodes are likely to be misaligned with respect to the common electrode, making it difficult to set the spacing with high precision.

In view of the above-mentioned problems, the present invention provides a method for manufacturing an edge-type thermal printing head in which a common electrode and individual current-carrying electrodes are drawn out to the same side of a continuous heating element. It is an object of the present invention to provide a method for manufacturing a thermal printing head in which the spacing between the printing head and the individual current-carrying electrodes can be precisely set to a desired value.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, in the method of manufacturing a thermal printing head of the present invention, a first common electrode portion extending in the printing width direction is provided on an insulating substrate, and a first common electrode portion extending in a direction perpendicular to the printing width direction from both ends of the first common electrode portion is provided on an insulating substrate. a third common electrode portion for each printed dot unit extending from the first common electrode portion at regular intervals along the longitudinal direction of the substrate and in a direction opposite to the extending direction of the second common electrode portion; forming a common conductive layer, forming an insulating layer covering the first common electrode portion and leaving the third common electrode portion uncovered on the common conductive layer, and forming an insulating layer on the substrate. , forming a fourth common electrode portion that overlaps the third common electrode portion at the non-coated portion and extends in the same direction as the third common electrode portion to the edge of the substrate; an individual current-carrying electrode portion extending parallel to the edge of the substrate from the edge of the substrate to the insulating layer and connected to a terminal of a drive circuit element on the insulating layer; A heating resistor is formed that extends in the longitudinal direction of the substrate via the electrode portion.

<Function> According to the above configuration, not only can the heating element be formed sufficiently close to the edge of the substrate, but also the individual current-carrying electrode part and the fourth common electrode part can be formed simultaneously in one process. Therefore, the distance between the individual current-carrying electrode parts and the fourth common electrode part is determined accurately, and unlike the conventional method in which the individual current-carrying electrode parts and the common electrode are formed in separate processes, the distance between the individual current-carrying electrode parts and the fourth common electrode part is determined accurately. There is no positional shift of the common electrode, and the spacing between the two can be accurately set to a desired value.

<Examples> Examples of the present invention will be described below with reference to the drawings.
Explain in detail.

FIG. 2 is a simplified plan view of a thermal printing head manufactured by the method of the present invention, and FIG.
It is a sectional view taken from the cutting plane line in the figure, and the fourth
The figure is a sectional view taken along the cutting plane line - in FIG. 2. In these figures, parts corresponding to those in FIG. 1 are given the same reference numerals.

The thermal printing head 1' of this embodiment includes an insulating substrate 3, and a glaze layer 7 as a heat storage layer is formed over the entire upper surface of the substrate 3. 4
is a drive circuit that controls the energization of the band-shaped heating resistor 2 formed along the print width direction, and energizes the heating resistor 2 via a plurality of individual energizing electrode portions 5' for each printing dot unit. . 8 is an insulating layer;
This insulating layer 8 is formed in a rectangular shape on a first common electrode section 6a to be described later, and on this insulating layer 8, a part of the individual current-carrying electrode section 5', the drive circuit 4, etc. are provided.

6 is a common electrode, and this common electrode 6 is a first common electrode portion 6a formed on the glaze layer 7 of the substrate 3 and extending in the print width direction (left-right direction in FIG. 2).
and second electrodes extending from both ends of the first common electrode section 6a in a direction perpendicular to the print width direction (vertical direction in FIG. 2).
The common electrode part 6b and the first common electrode part 6a are spaced at regular intervals along the longitudinal direction of the substrate 3, and in the opposite direction to the extending direction of the second common electrode part (upper part in FIG. 2).
a common conductive layer consisting of a plurality of third common electrode portions 6c for each printed dot unit extending to
It includes a plurality of fourth common electrode parts 6d, each of which partially overlaps the plurality of third common electrode parts 6c (the shaded part in FIG. 2).

FIG. 5 shows the manufacturing process of the thermal printing head 1' shown in FIG.
That is, it is a plan view for explaining the method of the present invention.

In the method for manufacturing a thermal printing head of the present invention, first, a first common electrode portion extending in the printing width direction is formed as a first layer common electrode 6 on the glaze layer 7 of the insulating substrate 3, as shown in FIG. 5a. 6a, and a second common electrode portion 6b extending vertically from both ends of the first common electrode portion 6a in the printing width direction (vertical direction in FIG. 5).
and the first common electrode section 6a to the second common electrode section 6b.
A plurality of third common electrode portions 6c are provided for each printed dot unit A extending in a direction opposite to the extending direction (upward in FIG. 5).
are formed respectively to form a common conductive layer.

Next, as shown in FIG. 5b, a rectangular insulating layer 8 is formed on this common conductive layer, covering the first common electrode part 6a and leaving the third common electrode part 6c uncovered. do.

Next, as shown in FIG. 5c, a plurality of third common electrode portions 6c, each of which partially overlaps the plurality of third common electrode portions 6c (shaded portions in FIG. 5c), are formed as a second-layer common electrode. Four common electrode portions 6d are formed up to the edge of the substrate 3 along a direction perpendicular to the print width direction (vertical direction in FIG. 5c).

Between these fourth common electrode parts 6d, 6d, a plurality of individual current-carrying electrode parts 5' are formed from the edge of the substrate 3 to the insulating layer in parallel with the fourth common electrode part 6d. The formation of this individual current-carrying electrode section 5' is carried out by forming the fourth common electrode section 6.
This is carried out at the same time as the formation of d, and usually a single mask having a shape corresponding to both the individual current-carrying electrode portion 5' and the fourth common electrode portion 6d is used.

Finally, as shown in FIG. 5d, the heating resistor 2 connecting the fourth common electrode section 6d and the individual current-carrying electrode section 5' is formed in the print width direction, that is, in the longitudinal direction of the substrate 3.

In the thermal printing head 1' manufactured by this method, the current from the drive circuit 4 is passed through the individual current-carrying electrode section 5' for each printing dot to the heating resistor 2.
, and further passes through the fourth common electrode section 6d, reaches the third common electrode section 6c located below it, and further flows to the first common electrode section 6a and the second common electrode section 6b.

As described above, in the method of manufacturing a thermal printing head of the present invention, the first layer, the second layer,
After forming a common conductive layer consisting of third common electrode portions 6a, 6b, and 6c, and then forming an insulating layer 8,
A fourth common electrode portion 6d is formed as the second layer common electrode 6. Therefore, unlike the conventional example shown in FIG. 2 can be moved sufficiently close to the edge of the substrate 3 as shown in FIG.

<Effects of the Invention> As described above, according to the method of the present invention, a first common electrode portion extending in the print width direction is provided on an insulating substrate,
a second common electrode section extending perpendicularly to the printing width direction from both ends of the first common electrode section; A third common electrode part for each printed dot unit extending in the opposite direction to the extending direction is formed as a common conductive layer, and the first common electrode part is covered on the common conductive layer, and the third common electrode part is formed on the common conductive layer. An insulating layer is formed on the substrate with the common electrode portion being an uncovered portion, and an insulating layer is formed on the substrate so as to overlap the third common electrode portion at the uncovered portion and extend in the same direction as the third common electrode portion. A fourth common electrode part extending to the edge is formed, and at the same time, an individual energizing member extends parallel to the fourth common electrode part from the edge of the substrate to the insulating layer and is connected to the terminal of the drive circuit element on the insulating layer. forming an electrode portion on the substrate;
Since a heating resistor extending in the longitudinal direction of the board is formed via the common electrode part and the individual current-carrying electrode part, not only can the heating element be formed sufficiently close to the edge of the board, but also the heating element can be formed with the same Since the individual current-carrying electrode parts and the fourth common electrode part which are arranged in parallel alternately on the sides can be formed simultaneously in one process, the interval between the individual current-carrying electrode parts and the fourth common electrode part is accurately determined. Unlike conventional methods in which the individual current-carrying electrode parts and the common electrode are formed in separate processes in parallel, there is no misalignment of the common electrode with respect to the current-carrying electrode, and the distance between the two can be accurately set to the desired value. .

[Brief explanation of drawings]

FIG. 1 is a simplified plan view of a conventional example, FIG. 2 is a plan view of an embodiment of a thermal printing head manufactured by the method of the present invention, and FIG. 3 is a cross-section line of FIG. 2.
FIG. 4 is a cross-sectional view taken along the cutting plane line in FIG. 2, and FIGS. 5 a to 5 d are plan views for explaining the manufacturing process of the embodiment shown in FIG. 2. 1, 1'...Thermal printing head, 2...Heating resistor, 3
...Substrate, 5, 5'...Individual current-carrying electrode, 6...Common electrode,
6a to 6d...first to fourth common electrode parts, 8...insulating layer.

Claims (1)

[Scope of Claims] 1. A first common electrode portion extending in the print width direction on an insulating substrate, and a second common electrode portion extending perpendicularly to the print width direction from both ends of the first common electrode portion; A third common electrode part for each printing dot unit is formed from the first common electrode part at regular intervals along the longitudinal direction of the substrate and in a direction opposite to the extending direction of the second common electrode part. forming an insulating layer on the common conductive layer, covering the first common electrode portion and leaving the third common electrode portion as an uncovered portion; forming a fourth common electrode part that overlaps the third common electrode part and extends in the same direction as the third common electrode part to the edge of the substrate; forming an individual current-carrying electrode portion extending from an edge of the substrate to the insulating layer and connected to a terminal of a drive circuit element on the insulating layer; A method of manufacturing a thermal printing head, comprising forming a heating resistor extending in the longitudinal direction of the head.