JPH04173259A - Thermal head - Google Patents

Abstract

PURPOSE:To make a thermal head compact by connecting a conductive wiring on a board with an outer conductive lead at a part where there is no glaze layer. CONSTITUTION:A thermal head comprises a heat generating board 3 having a common electrode 1 and a glaze layer 2, a heat generating resistor 7 having a heat generating resistance 7a, a protective film 9, and a base film 11 arranged on the heat generating board 3 at a part where there is no glaze layer and having on the rear face a conductive lead 6 connecting a second conductive wiring 5 from a driving IC 10 constituted lower than the top surface of the heat generating resistance 7a. In order to connect the second conductive wiring 5 arranged on the heat generating board 3 with the conductive lead 6 arranged on the base film 11 from the driving IC 10, an insulating resin 12 is provided between the heat generating board 3 and the base film 11, the second conductive wiring 5 is made to coincide with the conductive lead 6, the base film is pressurized, the insulating resin 12 is pushed out around, and the conductive lead 6 is contacted to the second conductive wiring 5 electrically. The insulating resin 12 is cured by ultraviolet rays or heating.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a thermal head used in various printing devices.

2. Description of the Related Art A conventional thermal head has a glaze layer 22 provided on the upper surface of a heating element substrate 23, as shown in FIG.
A heating resistor 27 is formed on a heating element substrate 23 including 2,
A common electrode 21 is provided at one end of the heating resistor 27, a first conductor wiring 24 is provided on the common polarization 21, and a second conductor wiring 25 is provided on the upper surface of the heating resistor 27. A protective film 29 is formed on the exposed second conductor wiring 25 on the glaze layer 22, and a drive 1 (, 3
o and at! connected to this drive IC 30! J-
The conductive lead 26 of the base film 31 having the lead 26 was connected to the groove bottom.

As described above, the second conductor wiring 25 and the base film 31
The connection of the conductive lead 26 of the heating element J+ (was performed on the glaze layer 22 of the plate 23).The reason for this configuration is that the connection of the conductive lead 26 of the heating element This is because heat bonding is performed when connecting 26, and the glaze layer 22 serving as a heat storage layer is required to perform this action.

Problems to be Solved by the Invention However, in the above conventional configuration, the same glaze layer 2
2 on the heating resistor 27. Conductive lead 26 and heating element board 2
The connection portion of the second conductor wiring 25 on the top 3 is arranged, and the conductive lead of the connection portion is higher than the surface of the heating resistor portion 27&,
A sufficient distance is required so that the platen roller 28 operated on the heating resistor 27a during printing does not come into contact with the conductive lead of the connection part. Therefore, there is a problem in that it becomes an obstacle to miniaturization of the thermal head.

The present invention aims to eliminate the above-mentioned conventional drawbacks and provide a thermal head that can be made smaller.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention has a structure in which the conductor wiring on the substrate and the external conductive leads are connected in a portion without a glaze layer.

Effect: With the above configuration, the platen roller operated on the heat generating resistor does not come into contact with the conductive leads, making it possible to reduce the size of the heat generating substrate. Therefore, the thermal head can be made smaller.

Examples of the present invention - "JJ JAi Example 1, HP'
This will be explained with reference to FIG.

The thermal head of the present invention has bars/common electrodes 1 disposed on one region and on the other region along the longitudinal direction.
and a heating element 1 made of alumina or the like having a glaze layer 2. (: A plurality of pieces are arranged along the longitudinal direction on the plate 3 and the glaze layer 2, and one end portion and the other end portion of each are connected to each other via the first conductor wiring 4 and the second conductor wiring 5. 'ilj A heating resistor 7 having a heating resistor 72L connected to the pole 1 and the connection part with the external conductive lead, and capable of performing desired printing on the printing paper according to the operation of the platen roller 8. A protective film 9 that protects this heating resistor 7 and the first and second conductor wirings 4 and 5
and a conductive lead 6 as an external conductor lead that is disposed in a portion of the heating element substrate 3 where the glaze layer 2 does not exist, has a driving IC 10, and connects the second conductive wiring 5 from the driving IC 10.
The base film 11 has a base film 11 on the back surface and is lower than the surface of the heating resistor part γB. Here, in order to connect the second conductor wiring 5 cut out on the heating element substrate 3 and the conductive IJ-F' 8 disposed on the base film 11'' from the driving part C10, the heating element substrate 3 and An insulating resin 12 such as epoxy, silicone, acrylic, etc. is interposed between the base film 11 and the second conductor wiring 5 and the conductive lead 6 are matched, and the matched upper nopace film 11 is pressurized. 6 to 2nd
Press it against the conductor wiring 5. At this time, the insulating resin 12 is pushed out to the periphery and the conductive lead 6 comes into electrical contact with the second conductor wiring 5.

Next, with the base film 11 under pressure, the insulating resin 12 is cured by ultraviolet rays or heating. At this time, the conductive lead 6 is electrically connected by the adhesive force between the second conductor wiring 5 and the insulating resin 12, and at the same time the base film 11
can be fixed to the heating element substrate 3.

With this configuration, even if the sulfate roller 8 and the base film 11 are spaced 17Jj apart from each other above the heating resistor 7a, they will not come into contact with each other, and printing will not be affected.

Effects of the Invention As described above, the present invention connects the conductive wiring on the substrate and the external conductive leads in large parts of the glaze layer of the heating element substrate, thereby reducing the size of the heating element substrate and reducing the size of the heating element substrate. Pricing and cattle's tendency can be realized. Therefore, the thermal head can also be made smaller. Furthermore, the surface roughness of the conductor wiring in the portion without the glaze layer is increased, and sufficient contact points with external conductive leads can be ensured to improve the reliability of the connection.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the thermal head of the present invention, and FIG. 2 is a sectional view showing a conventional thermal head. 1... Common electrode, 2... Glaze layer, 3
...Heating element board, 4...First conductor wiring,
5...Second conductor wiring, 6...Conductive lead, Finish...Heating resistor, 7a...Emission 1
1s Resistance section, 8...Platen roller, 9...
...protective film, 10...driver (,11...
... Base film, 12 ... Insulating resin.

Claims (1)

[Claims] A plurality of heat-generating resistors are arranged in a row, and a substrate having a glaze layer and a common electrode with conductor wiring connected to the heat-generating resistors is connected to an external conductive lead and a conductor in a portion where the glaze layer is not present. A thermal head made by connecting wiring.