JPH0248960A - Thermal head - Google Patents

Abstract

PURPOSE:To enable the manufacture with good yield and low cost and to maintain printing quality of a high level for a long time by a method wherein a heating resistor layer is formed over from a slant surface to a parallel surface, and a load dispatching material layer is respectively arranged on the slant surface and the parallel surface. CONSTITUTION:Since a glaze layer 12 is largely gently so etched that an almost flat slant surface 14 is formed from a heating resistor layer 13 to an end part of an insulating material 11, i.e. since the slant surface 14 is sloped by an inclination of 10 deg. to 15 deg. capable of being formed easily from a standpoint of fabrication, there is no trouble for etching. Further, heat conductivity of the heating resistor layer 13 is never impaired by action of resilience and deflexion of a platen even by this inclination angle. Therefore, enough pressure contact force is maintained by this fact when ink is solidified by cooling, and excellent printability can be displayed even for rough paper.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermal head used in a Sarnle printer, and particularly to a thin film type thermal head.

[Conventional technology]

The thermal head installed in a thermal printer, for example, has multiple heating resistor layers arranged linearly on the same substrate.
This heating resistor layer is heated with electricity according to the information, and is used for color recording on thermosensitive recording paper, or for transfer recording on plain paper via an ink ribbon.

FIGS. 7 and 8 respectively show the general structure of a conventional thermal head of this type and the state in which it is pressed against a platen of a printer.

In FIGS. 7 and 8, a glaze layer 2 made of glass that functions as a heat storage layer is formed on an insulating substrate 1 such as a ceramic substrate.
In FIG. 7, it is formed in a planar shape over almost the entire surface of the insulating substrate 1, and in FIG. 8, the cross section of the upper surface is formed in the shape of an arc in the area where the heating resistor is to be formed. On this glaze layer 2, a plurality of heat generating resistor layers 3 made of 2N, 2N, etc. are deposited by vapor deposition, sputtering, etc., and then arranged and formed in a linear manner by etching. A power supply body 114 is further formed on the heat generating resistor layer 3 for supplying power to the heat generating resistor layer 3. This power supply body [14 is made of aluminum, copper, gold, etc., for example, and is formed into a desired shape pattern by vapor deposition or sputtering.
One side is led out as a common power supply layer 4A, and the other side is led out as a signal power supply layer 114B on both sides of 3. In the pair of common power feeders W4A and the signal power feeder layer 4B, each independent heat generating resistor 113 formed with a heating area equivalent to one dot is connected to both of the pair of power feeders W4A and signal power feeder layer 4B. Heat is generated by applying a voltage between 24A and 4B.

A protection H5 for protecting the heat generating resistor layer 3 and the power supply layer 4 is formed on the heat generating resistor a13 and the power supply layer 4 described above. This protective layer 5 includes an oxidation-resistant layer made of S, O2, etc. that protects the heat-generating resistor layer 3 from deterioration due to oxidation, and is laminated on this oxidized layer.
The protective layer 111i5 is made of a wear-resistant layer made of 'a205, etc., which protects the heat generating resistor layer 3 and the power supply layer 4 from wear due to contact with the terminals. It has become. The oxidation-resistant layer and wear-resistant layer of the protective layer 5 are sequentially formed by means such as sputtering, and then, in the final step, the insulating substrate 1 is divided to obtain desired thermal head chips.

In addition, as the printing quality of thermal head printers has improved in recent years, the structure of the thermal head has changed from the conventional one in which the heating resistor layer 3 and the power supply layer 4 are arranged on a flat surface as shown in Fig. 7. As shown in FIG. 8, a glaze layer 2 having an arcuate cross-section is provided, and a convex portion 2A having an isosceles trapezoidal cross-section is further formed on the top surface of the glaze layer 2. The heat generating body WJ3 is placed on the section 2A. As a result, the power supply body Lti4
is disposed lower than the heating resistor layer 3, and the contact with the heat-sensitive recording medium 6 can be improved. In addition, as shown in Figure 8, when printing, the head is brought into contact with the printer's platen 7 at a slight angle of 1° to 3°, and in a thermal transfer type printer, the ink on the ink ribbon R is heated to a melt viscosity. The printing quality has been considerably improved even for rough vapor paper P, which has a large surface unevenness, by using a high @4VB system and by using a real edge that accelerates the peeling timing of the ink ribbon R.

[Problem to be solved by the invention]

However, in the configuration shown in FIG. 8 described above, when the convex portion 2A having an isosceles trapezoidal cross section is formed as described above on the glaze [12], and the heating resistor layer 3 is disposed on the convex portion 2A, If the height of the convex portion 2A exceeds 10 μm, there is a serious problem in that the yield of circuit patterning using photolithography technology is significantly reduced, making it difficult to produce a finished product.
There is a restriction that the height of the convex portion 2A cannot be made arbitrarily higher than 10 μTrL.

Therefore, the inclined surface of the convex portion 2A having an isosceles trapezoidal cross section and the upper surface of the glaze 1m2 form an inverted shape, and the ink ribbon R
Since a gap is formed between the molten ink and the protective layer 5 of the thermal head, the pressure of the ink ribbon R against the paper P is insufficiently maintained during the solidification process of the molten ink. From ink ribbon R to paper P
The ink is not transferred reliably to the paper, which deteriorates printing performance, especially on rough paper. In order to solve this problem, conventional methods have been taken such as increasing the energy applied to the thermal head or increasing the pressure force of the thermal head against the platen 7 of the printer.
As a result, the lifespan of the thermal head may be shortened, or background smudges due to ink may occur during printing.
There is a point.

The present invention overcomes the problems of the conventional products described above, can perform good printing, has a good manufacturing yield, can be manufactured at low cost, and furthermore maintains a high level of printing quality over a long period of time. Thermal head 4i, which can print well even on rough paper:
The purpose is to provide

(Means for Solving the Problems) A thermal head according to claim 1 for achieving the above-mentioned object includes a glaze layer provided on an insulating substrate, and a glaze layer formed on one end of the insulating substrate on the glaze layer. In a thermal head that includes a heating resistor layer located nearby, and a common power supply layer and a signal power supply layer that feed power to the heat generating resistor layer, the upper surface of the glaze layer at one end of the insulating substrate is The insulating substrate is formed into an inclined surface that is inclined so that one end aos is at a lower level, and the upper surface of the glaze layer that is continuous with this inclined surface is formed into a parallel surface that is substantially parallel to the upper surface of the insulating substrate. A heating resistor layer is formed from the inclined surface to the parallel surface, and a power supply layer is provided on the inclined surface and the parallel surface, respectively.

Further, in the thermal head according to claim 2, there is provided another inclined surface between the parallel surface and the inclined surface, which slopes upward from the parallel surface toward the inclined surface. It is characterized in that a convex portion is formed through the .

Furthermore, in the thermal head according to claim 3, a glaze layer is provided on the upper insulating substrate, and a heating resistor layer located on the glaze layer near one end of the insulating substrate; In a thermal head in which a common power supply layer and a signal power supply layer are arranged to supply power to the layers, the upper surface of the glaze layer at one end of the insulating substrate is tilted so that the one end side of the insulating substrate is at a lower level. forming the glaze layer into a parallel surface substantially parallel to the top surface of the insulating substrate;
forming a heating resistor layer from the inclined surface to the parallel surface;
The invention is characterized in that the common power supply layer and the signal power supply layer are led out from the heating resistor layer in the same direction.

[For production]

According to the thermal head having the above-mentioned configuration, the heating resistor layer is printed by making the inclined surface and the platen surface parallel and applying a pressing force while interposing the ink ribbon and the paper between them. There is no gap between the melted ink and the ink ribbon when it solidifies due to the heat generated by the heat generated by the paper, and the inclined surface of the flat head allows the paper to be held against the platen under pressure, even if the paper is rough. The ink ribbon blends into the surface, allowing the ink to adhere firmly to the surface, resulting in good print quality.

In addition, good print quality can be obtained without increasing the energy applied to the thermal head or the pressure force of the thermal head against the platen unnecessarily, which extends the life of the thermal head and prevents stains on the paper due to ink. can also be prevented.

〔Example〕

The present invention will be explained below with reference to embodiments shown in the drawings.

FIG. 1 shows a first embodiment of a linear head according to the present invention, and reference numeral 11 in the figure indicates an insulating substrate, and this insulating substrate 11 is made of alumina or the like. . A glaze [112] having a thickness of approximately 50 μm is baked onto the insulating substrate 11. Heat generating resistor 111
The upper surface of the glaze layer 12 at one end of the insulating substrate 11, which is the formation region of the glaze layer 13, is an inclined surface 14 that is inclined so that the one end side of the insulating substrate 11 is at a lower level. This inclined surface 14 is 10° to 1° with respect to the upper surface of the insulating substrate 11.
It is formed to form an inclination angle of 5°. It should be noted that as the inclination angle of the inclined surface 14 increases beyond 15°, the pressing force of the heating resistor layer 13 to the paper P becomes weaker, and as the inclination angle decreases to 10° or less, the pressing force decreases. is dispersed, and if the paper P is rough paper, printing performance will deteriorate.

The inclined surface 14 is formed by a photolithography technique in which a layer with a high etching rate is formed on the surface of the glaze 112 and then etched. On the other hand, the upper surface of the glaze WJ12 connected to the inclined surface 14 is a parallel surface 15 that is substantially parallel to the upper surface of the insulating substrate 11.

The heating resistor layer 13 made of Ta2N or the like is formed on the upper surface of the glaze WJ12 from the inclined surface 14, which is the area where the heating resistor layer 13 is to be formed, to the parallel surface 15. Further, the inclined surface 14 on the upper surface of the glaze layer 12
Above is a common power supply layer 16A that supplies power to the heat generating resistor layer 13.
A signal power supply body 3116B is formed on the parallel surface 15 on the upper surface of the glazes 11 and 12 to supply power to the heating resistor layer 13 in response to a print signal. These common power supply layer 16A and signal power supply layer 16B are each formed of AJ, etc., and these common power supply layer 16A and signal power supply layer 16B make the power supply 11
16 is constructed, and this power supply layer 16 is formed of a metal plate or the like. Further, the heating resistor [113 and the power supply layer 16 are formed by sputtering and photolithography.

On the surfaces of the heat generating resistor 1f13 and the power supply layer 16, a protection layer 11117 having oxidation resistance and wear resistance is applied so as to cover almost the entire surface. It has an i-layer.

Also, the inclined surface 14 is connected to the surface of the platen 19 of the printer.
The orientation of the thermal head is regulated so that the ink ribbon R and paper P are substantially parallel, and the alignment 19 can be pressed against the inclined surface 14 via the ink ribbon R and paper P.

Next, the operation of this embodiment having the above-described configuration will be explained.

During printing, the presence of the inclined surface 14 of the glaze layer 12 allows the ink ribbon R and the paper P to be tightly sandwiched between the thermal head and the platen 19 with sufficient pressure, so that the paper P is reliably held in the state where the molten ink solidifies. The ink can be reliably transferred from the ink ribbon R to the paper P. Therefore, even if the paper P is rough paper, the ink ribbon R conforms to the surface of the paper P, so that the ink of the ink ribbon R can be reliably transferred to the paper P. As a result, it is no longer necessary to increase the energy applied to the thermal head or to increase the pressure of the thermal head against the platen of the printer, extending the life of the thermal head and eliminating background stains on the paper P caused by ink.

Further, according to this embodiment, since the glaze W412 is largely and gently etched so as to form a substantially flat sloped surface 14 from the heating resistor layer 13 to the end of the insulating substrate 11, that is, the sloped surface 14 Since the angle of inclination is 10' to 15°, which can be easily formed during etching, there is no problem in etching.
Also, at this angle of inclination, the elasticity of the platen 19 and the I
Due to the effect of Q, the heat conduction of the heating resistor layer 13 is not impaired. Therefore, due to this as well, sufficient pressure contact force is maintained during cooling and assimilation of the ink, and good printing performance can be exhibited even on rough paper.

FIG. 2 shows a second embodiment of the thermal head according to the present invention, which differs from the first embodiment described above in that the glaze layer 12 between the inclined surface 14 and the parallel surface 15 is Another inclined surface 20 is formed on the upper surface, which slopes upward from the parallel surface 15 toward the inclined surface 14.
The other configuration is the same as that of the first embodiment described above, except that a convex portion 21 is formed between the inclined surfaces 20 and the inclined surface 22 is parallel to the upper surface of the insulating substrate 11. . The height difference of this slope 20 is about 2 μm, which is smaller than the height difference of the slope 14. In addition, when forming the slopes 14°20 at both ends, since the height difference between the slopes 14 at both ends and the slope 20 is different, it is not possible to form the slopes 14°20 at both ends at the same time. In this example, each inclined surface 14 and inclined surface 20 are formed by etching separately in two steps.

According to the second embodiment having the above-described configuration, substantially the same effects as those of the first embodiment can be achieved.

In addition, in the first embodiment described above, the heating resistor layer 1
Since the upper retainer 1111!17 of 3 was formed in a concave shape, the ink ribbon R and the paper P fit into this concave part 17A and come into contact with the protective layer 17, as shown by O in FIG. As a result, the pressure contact force of the heat generating resistor layer 13 becomes somewhat weaker, whereas in the second embodiment, the retaining IJli 17 above the heat generating resistor 113 is formed in a convex shape. Ink ribbon R as shown by mark Q
In addition, excessive contact of the paper P with the thermal head is avoided, and sufficient pressure contact force of the heating resistor 113 can be obtained, further improving print quality.

3 and 4 show the third and fourth embodiments of the present invention, respectively, and the embodiment in FIG.
A glaze that is almost the same as the first example explained with the drawings! l
112, and the embodiment shown in FIG.
It has 12 shapes. The difference between these third and fourth embodiments from the first and second embodiments is that in the first and second embodiments, the signal feeder 116B is formed on the parallel surface 15. and the common power feeder 1116A was formed on the inclined surface 14, whereas in the third and fourth embodiments, the common power feeder 11M16A and the signal power feeder layer 16B are both formed on the parallel surface 1.
This is the point formed on 5. Note that the method of forming each component in these third and fourth embodiments is the same as in the first and second embodiments.

FIGS. 5 and 6 show the third and fourth embodiments described above.
Heat generating resistor 1113 and power supply layer 16 in the embodiment
First, the embodiment shown in FIG. 5 will be described. In the embodiment shown in FIG.
...is considered to be one set.

That is, in the embodiment shown in FIG. 3, the rectangular heating resistor layers 13 of the same shape extend from the inclined surface 14 to the parallel surface 15 of the glaze layer 12, and in the embodiment shown in FIG. The heat generating resistor layers 13a, 13b, 13c are formed in an array from the top of the 12 convex portions 21 to the slopes 14.20 at both ends, and four heating resistor layers 13a, 13b, 13c are formed from one end.
, 13d are each set as one set. Among these, heating resistor layers 13a at both ends of one set of heating resistors 1113
.

13d are connected to signal feeder layers 16B and 16B extending in parallel planes 151111, respectively, and to the central heat generating resistor layers 13b and 13c, one wire with a wider end is connected to the heating resistor layers 13b and 13c. A common power supply body 1116A is connected.

Furthermore, a pair of adjacent heating resistors 11113a and 13b
and heating resistor! ! 13c and 136 have free ends connected to each other by folded electrodes 23, 23, respectively. With such a configuration, when one signal power supply layer 16B is brought into conduction, the current from the common power supply layer 16A flows from the heating resistor layer 13b (13c) through the folded electrode 23 and the heating resistor 1113a (13d>). The flow 1 flows to one signal power feeder layer 16B, heating the heat generating resistor layers 13a, 13b or the heat generating resistors ff13c, 13d.Therefore, by bringing both signal power feeders) 116B into a conductive state, all four Heat generating resistor 111138-13d
is heated.

By the way, in the embodiment shown in FIG. 5, the pair of heat generating resistors H13a and 13b and the heat generating resistor layers 13C and 13d are respectively connected by folded electrodes 23 to form a common power supply layer 16.
In the embodiment shown in FIG. 6, the pair of heating resistors shown in FIG. The common power supply layer 16A and the signal power supply body 1116B are led out to the parallel surface 15 side so that the body layer 13.degree. 13 and the folded electrode 23 serve as both.

According to the embodiment shown in FIG. 3 described above, the same pressing force as in FIG. 1 described above can be applied from the thermal head to the ink ribbon R and paper P. It is firmly attached to the paper P,
Ink can be reliably transferred from the ink ribbon R to the paper P, and therefore, the ink from the ink ribbon R can be reliably transferred to the paper P even if the paper P is rough paper. As a result, there is no need to increase the energy applied to the thermal head or the pressure of the thermal head against the inside of the printer's platen.
Moreover, the power supply body 1 made of a relatively soft metal such as Aj is placed on the side of the inclined surface 14 that presses the ink ribbon R and the paper P.
116 is not present, the power supply body 11016 is not damaged due to pressure contact of the thermal head, so the life of the thermal head is extended, and since the pressure contact force is not increased, there is no background stain on the paper P due to ink.

On the other hand, according to the embodiment shown in FIG. 4 described above, the glaze layer 1
A convex portion 21 is formed between the inclined surface 14 and the parallel surface 15 of the ink ribbon R, which prevents unnecessary parts of the ink ribbon R from coming into contact with the thermal head, and applies a large pressure contact force to the necessary parts of the ink ribbon R. Furthermore, since the power supply layer 16 is not present on the inclined surface 14 side as in FIG. 3 described above, it is possible to perform printing of even better quality than that in FIG. Similar to the embodiment shown in FIG. 3, the life of the thermal head can be extended.

Note that the present invention is not limited to the embodiments described above, and various changes can be made as necessary.

(Effects of the Invention) As explained above, according to the present invention, it is possible to perform good printing, have a good manufacturing yield, be manufactured at low cost, and further maintain a high level of printing quality over a long period of time. This has the excellent effect of being able to perform good printing even on rough paper.In addition, according to claim 3, the power supply layer is not on the side that requires pressure contact force. In this case, the power supply layer is not damaged by the press-contact force, and the life can be extended due to this point as well.

16B... Signal feeder layer, 19... Platen, 21
...Protrusion, P...Paper, R...Ink ribbon.

Claims (1)

[Scope of Claims] 1) A glaze layer is provided on an insulating substrate, and a heating resistor layer located on the glaze layer near one end of the insulating substrate, and a common layer that supplies power to the heating resistor layer. In a thermal head including a power supply layer and a signal power supply layer, the upper surface of the glaze layer at one end of the insulating substrate is formed into an inclined surface such that the one end side of the insulating substrate is at a lower level. At the same time, the upper surface of the glaze layer continuous with the inclined surface is formed into a parallel surface substantially parallel to the upper surface of the insulating substrate, and a heating resistor layer is formed from the inclined surface to the parallel surface, and a thermal head, characterized in that a power supply layer is disposed on each of the parallel surfaces. 2) A convex portion is formed between the parallel surface and the inclined surface via another inclined surface having an upward slope from the parallel surface to the inclined surface. thermal head. 3) A glaze layer is provided on the upper insulating substrate 1, and on this glaze layer, a heating resistor layer located near one end of the insulating substrate, a common power supply layer and a signal that feeds power to this heating resistor layer. In the thermal head, the upper surface of the glaze layer at one end of the insulating substrate is formed into an inclined surface such that the one end side of the insulating substrate is at a lower level. The upper surface of the glaze layer continuous with the surface is formed into a parallel surface substantially parallel to the upper surface of the insulating substrate, a heating resistor layer is formed from the inclined surface to the parallel surface, and the common power supply layer and the signal power supply layer are formed. A thermal head characterized in that a body layer is led out in the same direction from the heating resistor layer.