JPS59167276A - Thermal head - Google Patents

Abstract

PURPOSE:To attain to enhance recording quality and to accelerate a recording speed in heat sensitive printing recording, by forming a heat accumulating layer comprising an insulating substance to the small gap part between a pair of opposed electrode wirings while forming a thin film heat generating resistor to the surface of said heat accumulating layer. CONSTITUTION:Electrode wirings 12a..., 13a... are formed on the surface of a surface smoothed insulating substrate 14 by thick film printing or etching processing. In this case, the electrode wirings 12a..., 13a... are set in opposed relation to each other at small intervals so as to correspond to a recording element part. In the next step, a heat accumulating material 15 comprising an insulating material is applied to the mutual small gap parts so as to include the electrode wiring part and polished until the electrode wirings 12a..., 13a... are exposed to form a heat accumulating layer 15a. Subsequently, heat generating resistors 16a... are formed on the surface of the heat accumulating layer 15a so as to mutually connect the opposed electrode wirings 12a..., 13a... by vapor deposition.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermal head used in thermal printing recording, which has good responsiveness to a signal current and allows accurate recording dots to be obtained.

A thermal head used for thermal printing recording is constructed by arranging a large number of heat-generating recording elements in a straight line at a high density, and selectively distributes and supplies a heat-generating signal current to the heat-generating recording elements. The recording paper is brought into contact with the recording element portion and moved relative to the recording paper, and the heat-generating recording element supplied with the signal current performs dot recording on the recording paper, and also records characters, symbols, figures, etc. Figure 1 shows the recording element array section of such a thermal head, in which a large number of heating resistors 118° Ilb, each serving as a dot recording element, are mounted on a base material made of an insulator. are formed in a linear arrangement at minute intervals on the specified surface.

Then, electrode wirings 12a, 12b, . . . and 13a, 13b, . . . are formed to be connected to the heating resistors 11a, Zlb, .
A heating signal current is selectively supplied to each of Ilb...

In this case, electrode wiring 12a, 12b..., 13a, 13
Along with b, , , the heating resistors Zla and llb are formed by thick film printing or etching on the smoothed surface of the base material, and are formed in a state that rises from the surface of the base material. Ru.

The heating resistor 11a formed in this way.

, Ilb... is one that generates heat when a signal current is supplied and records dots on the recording paper when the temperature reaches a high temperature. Yasugi is known for its fast response and recordable high temperatures. For this reason, it has been considered to form a heat storage layer made of an insulator on the surface of the base material 1 to store the heat generated by the heating resistor and improve the responsiveness to the signal current.

However, in each recording element of a thermal head configured in this way, a pair of electrode wirings for supplying a signal current are set facing each other at a small interval, and a heating resistor material is applied by printing or the like to the small interval. Therefore, the resistor inevitably has a thick film and its surface has a protruding mountain shape.

For this reason, it is difficult to make the heat generation response to the signal current sufficiently fast, and straddling is not possible, and the area of the dots is also small compared to the area of the heating resistor surface. In other words, it is still in an insufficient state to record high-resolution commercial quality images for 1 hour.

This invention is based on the above-mentioned points, and not only provides sufficient responsiveness to the signal current, but also enables recording dots to be clearly formed in accordance with the shape and size of the heat-generating recording element section. It is written and recorded, lJT! The present invention aims to provide a thermal head that can have a great effect on improving the quality of I-images.

An embodiment of the present invention will be described below with reference to the drawings. Figure 2 is a cross-sectional view of a portion corresponding to the heating resistor 11a in Figure 1, showing the manufacturing process. On the surface of the smoothed insulator base material Z4, conductive and electrical distribution is applied by applying a thick film 1], etching process, etc.
a..., 13a... are formed. In this case, the electrode wirings Z2a, . . . and I3a, . Then, electrode wirings 12a... and 13a... arranged as shown in (B+)
At the small distance between the
The heat storage layer I5 is coated including the electrode wiring parts (as shown in Figure 01).
... is formed on the surface, and the electrode wiring 12a is polished.
..., 13a... The heat storage layer 15 is flush with the surface.
form a. In this case, the heat storage layer 75a has a thickness of 20 to 40 μm.
The thickness is set to about m.

Then, as shown in the fDJ diagram, in the heat storage b15a15a,
The heating resistor 16a is entirely formed by forming a thin film of, for example, 1 μm or less by vapor deposition or the like so that the opposing electrode wirings 12 and 13 a are connected to each other.

That is, if configured as described above, the heating resistor Z6a
...1. While flowing in the state formed on the heat storage layer z s a, the power wiring 12a that supplies (Th) current to this
..., 13a..., and the heating resistor Z6a is formed with a smooth surface and an extremely thin film.
...becomes formed.

Therefore, the heat capacity of each of the heating resistors Z6a can be made very small, and the heating response to the signal current can be made very good. In this case, as a matter of course, the power consumption due to heat generation becomes sufficiently negligible.

At the same time, the heating resistors 16a... can be reliably constructed in a flat state, so that the entire surface thereof is surely in contact with the recording paper, and the surface shape of each heating resistor is accurate. This makes it possible to record dots on recording paper. Therefore, very clear dots can be formed on the recording paper, and in cooperation with the above-mentioned exothermic responsiveness, it is possible to achieve very high quality recording.

Furthermore, since the heating resistor can be made into an extremely thin film and formed by etching, etc., it is easy to arrange the heating resistors at high density, which increases the recording dot density and improves the resolution. Excellent thermal recording can now be easily performed.

In the above embodiment, the heat storage layer 1.5a is formed so as to extend in the direction in which a large number of heat generating resistors 16a... are arranged, and is common to each heat generating resistor 16a... However, each heating resistor Z6a...
- Of course, the heat storage layer may be formed independently for each.

FIG. 3 shows another example of the electrode structure, in which a plurality of electrode wirings 17a, 17b, . Further, other electrode wirings 18a, z8b, . . . are formed. Then, between the electrode wirings 17a and 18a, 18a and 77
The heating resistors Z6a, I6b, . . . are arranged between 17b and 18b, and between 17b and 18b, respectively. In this case, 17a and 18
Between 15 and 15'a, z8a and Z7b, heat storage portions are formed on the same plane as the respective electrode wirings at the lower part of the heating resistors 16a, 16b, . . . .

As described above, the present invention provides a thermal head with a sufficiently good exothermic response and a clear recording dot shape, and improves the quality of thermal printing records and the commercial speed. It has a very large effect on the

[Brief explanation of the drawing]

Figure 1 explains the configuration of the recording section of the thermal head. 8 to 8 (D+ in FIG. 2 are cross-sectional views illustrating the manufacturing process of a thermal head according to a practical example of the present invention, and FIG. 3 is a diagram showing another example of the configuration of the recording section. Z2a , 12b-=, 13a, Z 3b-electrode wiring, I4... insulator base material, 15'a... heat storage section, 16a
, 16b...heating resistor.

Claims (1)

[Claims] A large number of heat-generating recording elements are arranged and formed on the surface of an insulating base material having a smoothed surface, and each of these recording elements is formed of one thick film formed in pairs at small intervals. a pair of electrode wirings, a heat storage layer made of an insulator filled in the small space between the pair of electrode wirings and configured to have a surface that coincides with the surface of the electrode wiring portion; A thermal head comprising: a heating resistor made of a thin film formed including the pair of electrode wiring parts.