JPH0338351A - Thermal head and its manufacturing method - Google Patents

Abstract

PURPOSE:To obtain a thermal head with good responding efficiency and hard to cause blurs by providing nearly continuously a plurality of protruding bodies on a substrate with a predetermined distance spaced each other, electrodes at both sides of an upper surface of each of said protruding bodies, and a heat generating resistance body between said electrodes. CONSTITUTION:A heat storage layer 2 mainly composed of silicon dioxide is formed on an insulative substrate 1 made of aluminum. A plurality of electrodes 4 formed of at least one of chromium, nickel, tantalum, titanium, molybdenum, tungsten, cobalt and iron are continuously formed on the layer 2 with a predetermined distance spaced each other through sputtering or the like, and heated in an electric furnace from above at a temperature 30-50 deg.C lower than the melting point of glass of the layer 2 for about 6-10 minutes in the nitrogen ambience to prevent oxidation of the electrodes 4. As a result, the portion of the substrate 1 with the electrodes 4 is raised. The electrodes 4 are thus on a protruding body 2A protruding from the layer 2. The portion between both ends of each electrode 4 is cut, on which a heat generating resistance body 3 of rethenium oxide is linearly printed, dried and sintered. Then, an anti-abrasion layer 5 mainly formed of silicon dioxide is screen-printed, dried and sintered.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a thermal head and a method for manufacturing the same.

2. Description of the Related Art A conventional thermal head has a substrate la as shown in FIG.
A heat storage layer 2a is provided thereon, then a plurality of heating resistors 3a are successively provided while being separated by a predetermined interval, then electrodes 4a are provided on both sides of each heating resistor 3a, and finally, although not shown, It was constructed by forming an abrasion resistant layer.

Problems to be Solved by the Invention However, when the heat generating resistors 3a are provided on the flat heat storage layer 2a as in the past, a large heat capacity body is in contact with each heat generating resistor 3a. Therefore, the heating resistor 3a is difficult to generate heat when energized, and is also difficult to cool down when energization is subsequently stopped. This poses a problem in that the thermal head has poor responsiveness when energized, and smearing is likely to occur when energization is stopped.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a thermal head that has good responsiveness and is less likely to cause bleeding.

Means for Solving the Problems And in order to achieve this object, the present invention arranges a plurality of protrusions almost continuously on a substrate at predetermined distances, and on both sides of the upper surface of each protrusion. Electrodes are provided, and a heating resistor is provided between these electrodes.

According to the above-mentioned means, since the heating resistor is provided on the protrusion, the heat capacity under each heating resistor can be reduced, and as a result, responsiveness is improved when energization is applied, and the energization is stopped. Sometimes it becomes difficult to bleed.

Example An example of the present invention is shown below.

In Figure 1, 1 is an insulating substrate made of aluminum;
On top of this substrate 1 is a heat storage layer 2 mainly made of silicon dioxide.
As will be explained in detail with reference to FIG. 2 and subsequent figures, on this heat storage layer 2, an electrode 1 heating resistor and an abrasion resistant layer are provided.

That is, a heat storage layer 2 is provided on a substrate as shown in FIG. The electrodes 4 are separated by a predetermined interval and are continuously provided by a method such as sputtering. Next, the material shown in Fig. 3 is placed in an electric furnace, and heated from above at a temperature 30 to 50 degrees Celsius lower than the softening point of the glass of the heat storage layer 2 for about 6 to 10 minutes in a nitrogen atmosphere to prevent oxidation of the electrode 4. Heat it up.

As a result, the electrode 4 portion is raised as shown in FIG. This is because when heated at a high temperature, the electrode 4 tends to peel off due to stress, but the glass of the heat storage layer 2 is also heated at a high temperature and has a low viscosity, so it is pulled by the electrode 4, and its shape changes. When enlarged, the electrode 4 is placed on the protrusion 2A from the heat storage layer 2, as shown in FIG.

Next, in this state, as shown in FIG. 6, both ends of the electrode 4 are cut by photolithography or the like. Then, a heating resistor 3 made of ruthenium oxide is linearly printed on top of this by screen printing, dried at about 120° C. for about 15 minutes, and then fired at a temperature of about 800° C. In this state, as shown in FIG. 7, the heat generating resistor 3 falls between the electrodes 4 and into the bay between the protrusions 2A. However, protrusion 2A
Since the height of the projection 2A is high, the heating resistor 3 in the recess between the two does not electrically short-circuit with the upper surface, so it cannot be photolithographically removed.
Individual heating resistors 3 can be constructed without an etching process.

Next, from this state, a wear-resistant layer 5 mainly made of silicon dioxide was screen printed, and then dried and fired in substantially the same manner as the heating resistor 3, as shown in FIG.

In this example, the electrode 4 is made of at least one of chromium, nickel, tantalum, titanium, molybdenum tungsten, cobalt, and iron as the material of the electrode 4. However, if gold is provided on top of the material by the MOD method, the oxidation of the electrode 4 can be prevented. At the same time, it is possible to reduce the wiring resistance of the electrode 4, which is a layer effect.

Effects of the Invention As described above, in the present invention, a plurality of protrusions are arranged almost continuously on a substrate, separated by a predetermined distance, and electrodes are provided on both sides of the upper surface of each protrusion. Since the heat generating resistor is provided, the heat capacity under each heat generating resistor can be reduced, and as a result, responsiveness is improved when electricity is applied.
Bleeding is less likely to occur when the power is turned off.

[Brief explanation of drawings]

FIG. 1 is a perspective view of one embodiment of the present invention, FIGS. 2 to 7 are perspective views showing a manufacturing method thereof, and FIG. 8 is a perspective view of a conventional example. 1...Substrate, 2...Heat storage layer, 3...
...Heating resistor, 4...Electrode, 5...
・Abrasion resistant layer.

Claims (5)

[Claims] (1) A thermal system in which a plurality of protrusions are arranged almost continuously on a substrate, separated by a predetermined distance, electrodes are provided on both sides of the upper surface of each protrusion, and a heating resistor is provided between these electrodes. head. (2) The thermal head according to claim (1), wherein a recess is provided in a portion between the electrodes on the protrusion, and a heating resistor is provided in the recess. (3) Electrodes include chromium, nickel, tantalum, titanium,
The thermal head according to claim 1 or 2, comprising at least one of molybdenum, tungsten, cobalt, and iron. (4) A heat storage layer is provided on the substrate, and then a plurality of electrodes are provided almost continuously on this heat storage layer, separated by a predetermined interval, and then heated to raise the heat storage layer at the electrode portion to form a plurality of electrodes. A method for manufacturing a thermal head, comprising: providing a protrusion; then removing a portion between both ends of an electrode on the protrusion; and then providing a heating resistor in the removed portion. (5) Electrodes include chromium, nickel, tantalum, titanium,
The method for manufacturing a thermal head according to claim 4, wherein the thermal head is made of at least one of molybdenum, tungsten, cobalt, and iron.