JP2795050B2 - Thermal head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention is related to improvement of the thermal head for heat-sensitive paper printing.

[0002]

2. Description of the Related Art FIG. 30 is a plan view showing the structure of a heating element of a conventional thick film thermal head disclosed in, for example, JP-A-1-150556, wherein 1 is a common electrode lead, 2 is an individual electrode lead, Reference numeral 3 denotes a common electrode pattern in which common electrode leads are commonly connected. Reference numeral 4 denotes a common electrode reinforcing pattern formed by printing, drying, and baking, for example, an Ag paste or an Au paste, and provided for reducing the resistance value of the common electrode 3. 5, a heating resistor formed by applying, drying and firing a thick film resistor paste made of, for example, ruthenium oxide, zirconia, and a glass component, and formed in a strip shape so as to connect all the common electrode leads 1 and the individual electrode leads; 6 is one of the heating resistors 5
One unit of heating element which is a section and generates heat simultaneously by applying a voltage to one individual electrode 2, and two heating resistors 61 and 62 on both sides of one individual electrode 2 and constituting one heating element 6 Body. The heating resistor 5 may be formed as a cermet resistor or a polycrystalline metal resistor by a thin film forming process.

FIG. 31 is a manufacturing process diagram showing a manufacturing process of the heating element of the thermal head shown in FIG. Each step is as follows. (1) forming a conductor film for forming each of the electrodes 1, 2 and 3 on an insulating substrate (not shown in FIG. 30);
(2) The common electrode lead 1, the individual electrode lead 2, and the common electrode 3 are formed by patterning (selective etching),
(3) The common electrode reinforcing pattern 4 is formed by printing, drying and firing of an Ag paste, and (4) the heating resistor 5 is formed by applying, drying and firing of a resistance paste,
(5) A protective film for protecting the heating resistor 5 by printing, drying, and firing a glass paste (not shown in FIG. 30)
(6) The resistance value of each heating element 6 is made uniform by pulse trimming described later, and the heating element substrate is completed.

Next, the operation will be described. By applying a voltage to one individual electrode 2, one unit of the heating element 6 composed of the heating resistors 61 and 62 generates heat. Recording paper (not shown), which is a thermal paper, is pressed against the heating element 6, and color is generated by the heat generated by the heating element 6. As shown in FIG. 32A, the temperature distribution of the heating element 6 is such that the central portions H _L and H _R of the heating resistors 61 and 62 have the highest temperatures and have two elliptical high-temperature portions. Shows the distribution. FIG. 32 (b) is a cross-sectional view taken along the line AB in the plan view (a), and shows that the cross-section of the heating resistor 5 has a semi-cylindrical shape. This shape is because the heating resistor 5 is formed by applying a resistive paste.

The resistance value of the heating element 6 is determined by the heating resistors 61 and 6.
The parallel resistance value of 2 has a certain degree of non-uniformity depending on the individual heating elements. The lower the resistance value, the larger the current value for the same applied voltage, and thus the larger the amount of heat generated, resulting in a larger coloring area. In order to perform good printing, it is necessary that the coloring area of each heating element is uniform, and for that purpose, the resistance value of each heating element must be made uniform.

As a method of equalizing the resistance value of each heating element, there is a pulse trimming method shown in US Pat. No. 4,782,202, in which the average resistance value of each heating element is within ± 3%, and the resistance value of each heating element is less than ± 3%. Non-uniformity within ± 15% (standard deviation 2%
) Standard. The outline of the pulse trimming method will be described below. FIG. 33 shows a change in resistance value when a pulse having a higher voltage than that during normal use is applied to the heating element. In the figure, when a pulse having a voltage higher than V _O is applied, the resistance value decreases. In order to make the resistance value a desired value R _X , a pulse of the voltage V _X may be applied. However, this pulse application does not necessarily need to be given as a single pulse, and a pulse of a smaller voltage may be given a plurality of times in succession. It is considered that when a continuous pulse is applied, the effect of each pulse is accumulated as thermal energy. FIG. 34 shows the relationship between the number of pulses and the resistance value when divided into a plurality of pulses and given. The case where a relatively small pulse is given is indicated by a solid line, and the case where a large pulse is given is indicated by a dotted line. When the pulse voltage is small, the time required for adjusting the resistance value increases, but the resistance value can be finely adjusted.

Although the uniformity of the resistance value of the heating element 6 has been improved by the pulse trimming method described above, another problem which cannot be improved by this method remains.
That is, it is the resistance value of the heating element 6 that is equalized by the pulse trimming, that is, the parallel resistance value of the heating resistors 61 and 62, and the difference between the resistance values of the two resistors 61 and 62 cannot be equalized. That is. Therefore, there remains a problem that the shape of the coloring dots is biased due to the difference in the amount of heat generated between the heating resistors 61 and 62, and there is a limit in improving the uniformity of coloring by the pulse trimming method. In addition, the area ratio of a colored portion in the colored region allocated to each heating element is called a coloring efficiency. However, it is difficult to set the coloring efficiency to 100% because of the above-mentioned inconvenience. However, there still remains a problem that the colored dots protrude into the unnecessary area even if the number of dots does not reach the maximum value.

[0008]

Since the conventional thermal head is constructed as described above, the heating resistors 61 and 6 are used.
2 cannot be made the same, so that the shapes and sizes of the color dots become non-uniform, and sufficient color efficiency cannot be obtained.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the conventional thermal head and to provide a thermal head which has uniform color dot shapes and sizes, has a high coloring efficiency, and enables high quality printing. I do.

[0010]

According to a first aspect of the present invention, there is provided a thermal head including a common electrode, a plurality of common electrode leads connected to the common electrode in a comb shape, and one adjacent common electrode lead. And a plurality of individual electrode leads provided between the common electrode leads so that the gap between the individual electrode leads and the other common electrode lead is narrower than the gap between the individual electrode leads and the common electrode lead. a heating resistor that is, the number of the heating resistor
The distance between another electrode lead and this individual electrode lead becomes narrower
A protruding portion connected to the individual electrode lead or the one common electrode lead between the one common electrode lead positioned on one side, and the individual electrode lead and the An insulator is formed between one common electrode lead and the individual electrode lead and the individual electrode lead.
The other common electrode located on the side where the distance from the gate is wider
Heating elements are formed between the leads .

In the thermal head according to the second aspect of the present invention, a gap between a common electrode, a plurality of common electrode leads connected to the common electrode in a comb shape, and one adjacent common electrode lead is formed on the other side. A plurality of individual electrode leads respectively provided between the common electrode leads so as to be narrower than a gap with the common electrode lead, and these individual electrode leads and
The part for the narrow interval that straddles the common electrode lead
Heating resistor with insulating or high resistance components
For example, across the heating resistor provided oppositely disposed conductor portions to the common electrode, electrically to the conductor portion of the predetermined common electrode leads of the common electrode lead extend beyond the heating resistor Connected to.

The thermal head according to the third aspect of the present invention
Make the width of the common electrode lead larger than the width of the individual electrode leads.
It is widened.

The thermal head according to the fourth aspect of the present invention
The heating resistor contains zirconia, and its mass component ratio is
10% or less.

The thermal head according to a fifth aspect of the present invention
The heating resistor has a thickness of 1 μm to 4 μm.
You.

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

According to the first aspect of the present invention, the thermal head has a voltage mark.
Additional electrode lead or one common electrode lead
The vicinity of the connected protrusion generates heat preferentially,
Between the individual electrode lead and the one common electrode lead.
An insulator is formed therebetween.

The thermal head according to the second aspect of the present invention
The voltage drop due to the electric resistance of the through electrode can be reduced.

The thermal head according to the third aspect of the present invention
The voltage drop due to the electric resistance of the through electrode
It can be further reduced than a thermal head.

The thermal head according to the fourth aspect of the present invention
Insulation between the separate electrode lead and one common electrode lead
It can be easily formed, and the individual electrode lead and the other common electrode
The adjustment of the resistance value of the heating element between the heat sink and the heat sink can be easily performed.

The thermal head according to the fifth aspect of the present invention
Since the thermal resistor is 1 μm to 4 μm, stable production
Wear.

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

【Example】

Embodiment 1 FIG. FIG. 1 is a plan view showing the configuration of a heating element of one embodiment of a thermal head according to the present invention. Portions corresponding to the heating elements of the conventional thermal head shown in FIG. 30 are denoted by the same reference numerals, and description thereof will be omitted. The difference from the conventional example shown in FIG. 30 is that the individual electrode leads are periodically arranged with a large interval on one side and a small interval on the other side with respect to the common electrode on both sides, and the heating resistor 61 having a large width and the heating resistor 61 having a large width are arranged. Small heating resistor 62
And the heat-generating resistor 62 having a small width is broken by an electric pulse to insulate or increase the resistance. The destroyed heating element 62 becomes the insulator 8, and the heating element 6 becomes only the heating resistor 61. Reference numeral 14 denotes a crack generated by the destruction of the heating resistor 62.

In FIG. 33, when the pulse voltage is between V _O and V _L , the resistance value decreases as the pulse voltage increases. On the other hand, when the pulse voltage exceeds V _L , the resistance value increases as the pulse voltage increases. In V _D becomes insulated. This is because the heating resistor is destroyed by excessive heating. FIG.
Even if a pulse of a small voltage as shown in FIG. 4 is applied many times, the same state is obtained by increasing the number of times of application. FIG. 2 shows the relationship between the pulse voltage that leads to breakdown and the width of the heating resistor. The smaller the resistor width, the smaller the breakdown.

Since the heating resistors 61 and 62 form a parallel circuit, a voltage can be applied simultaneously by one individual electrode 2. However, if the difference between the widths of the resistors 61 and 62 is increased, the width is increased. Only the narrow resistor 62 is destroyed, and only the wide resistor 61 is left. Hereinafter, this operation is called open trimming. FIG. 3 shows a heating resistor 61.
The relationship between the breakdown voltages 62 and 62 is described for the embodiment. In this embodiment, the width of the heating resistor 61 is 100 μm,
The width of 62 is 5 μm, and its initial resistance is 3000Ω and 150Ω, respectively. In this embodiment, the width of the resistor 62 is small.
Has a breakdown voltage of 40V, and the breakdown voltage of the wide resistor 61 is 1
It was 10V. At an applied voltage of 40 V, only the resistor 62 was broken, and the resistor 61 was preserved and no change in the resistance value was observed.

FIG. 4 is a manufacturing process diagram showing the manufacturing process of the heating element of the first embodiment. The manufacturing process of the heating element of the conventional thermal head shown in FIG. 31 is obtained by adding the above-described open trimming step. . However, the open trimming process sequence may be performed before firing the glass paste when the firing temperature of the glass paste is low and does not affect the insulator 8 after the open trimming.

Next, the operation of the first embodiment will be described. FIG. 5 shows a temperature distribution of the heating element 6 of this embodiment. The conventional heating element shown in FIG. 32 has two heating resistors 61,
Two high-temperature portion H _L corresponding to 62, has a H _R, the heat generating portion is only the heating resistor 61 so that a dielectric body 8 heating resistors 62 are destroyed At a present embodiment . In the present embodiment, the number of heat generating portions is limited to one, so that two heat generating resistors 61 and 62, which are problems of the conventional heat generating element, are provided.
It was possible to eliminate unevenness in the shape and size of the coloring dots due to the difference in the calorific value of the above.

Next, the printing performance of this embodiment and a conventional thermal head will be compared. 6, 8, and 10 show the color dot size and color efficiency of a conventional thermal head.
Reference numerals 9 and 11 show the color dot size and color efficiency of the present embodiment. Here, the coloring efficiency is an area ratio of a colored portion in a coloring region assigned to each heating element. The coloring area is 1 in the main scanning direction (the direction in which the heating elements are arranged).
25 μm, about 130 μm in the sub scanning direction (recording paper transport direction)
It is. The comparison conditions were a main scanning pitch of 125 μm, a sub-scanning pitch of 130 μm, a printing speed of 10 ms / line, and a head pressure of 3.5 μm.
kg, and the recording paper used is thermal paper F240AC made by Mitsubishi Paper Mills.
It is. Pulse application condition is energy (millijoule)
It has been standardized. The width of the common electrode lead and the individual electrode lead is 10 μm in both the embodiment and the conventional example. The distance between the common electrode lead and the individual electrode lead is 52.5μm in the conventional example
In the embodiment, the large interval is 100 μm and the small interval is 5 μm.
μm.

FIGS. 6 and 7 compare the distribution of the print dot size of 100 points in the main scanning direction in each of the conventional example and the embodiment. Although the print dot size increases as the pulse application energy increases, it can be seen that the dot size uniformity is much better in the embodiment of FIG. 7 than in the conventional example of FIG. FIGS. 8 and 9 show the same comparison in the sub-scanning direction, and the embodiment of FIG.
The dot size uniformity is excellent as compared with the embodiment. FIGS. 10 and 11 show the conventional example and the embodiment, respectively.
It shows the distribution of the coloring efficiency of a point. In the conventional example of FIG. 10, the coloring efficiency is 40 to 10 when the applied energy is 0.225 mJ.
In the embodiment of FIG.
100%, 0.3mJ is 70-100% of the conventional example
On the other hand, all the examples reached 100%. From this, it can be seen that in the embodiment, the coloring efficiency is higher and the distribution uniformity is better than in the conventional example.

In this embodiment, the heating resistor 62 is completely made of an insulator by the open trimming process. However, it is not always necessary to make the heating resistor 62 a complete insulator. good.

Embodiment 2 FIG. FIGS. 12, 13 and 14 show a second embodiment of the present invention. In this embodiment, the common electrode leads 1 facing each other at the position of the heating resistor 61 having a large width are used.
And the individual electrode leads 2 are provided with projections. In this case, since the heating resistor in the portion where the electrode interval is narrowed by the convex portion generates heat preferentially, the position where the highest temperature portion is generated is stable, and the position and shape of the color dot are the first position shown in FIG. It becomes more uniform than in the embodiment. The shape of the convex portion is not particularly limited, and the convex portion may be provided on only one of the common electrode lead and the individual electrode lead.

Embodiment 3 FIG. FIG. 15 is a diagram showing a third embodiment of the present invention. In this embodiment, the heating resistor 6 having a large width is used.
A recess is provided in at least one of the common electrode lead 1 and the individual electrode lead 2 facing each other at the position 1. By doing so, the shape of the heating resistor 61 can be made larger, so that the coloring efficiency can be improved. Although the coloring effect can be improved by reducing the width of the common electrode lead and the individual electrode lead as a whole, it is difficult to stably form the electrode pattern, and the resistance value of the electrode lead increases. Is also not preferred. Therefore, it is desirable to reduce the width of the electrode lead only in the heating resistor portion. In combination with the second embodiment, as shown in FIG. 16, one of the common electrode lead and the individual electrode lead may be provided with a convex portion and the other with a concave portion.

Embodiment 4 FIG. FIG. 17 is a diagram showing a fourth embodiment of the present invention. In the present embodiment, a part or all of the common electrode lead 1 is extended beyond the heating resistor arrangement portion and connected to a conductor having the same potential as the common electrode. In this way, it is possible to prevent the supply voltage to the heating element 6 at the center of the heating element from being reduced due to the voltage drop due to the electric resistance of the common electrode 3, and to develop the color at the center and both ends of the heating element. The difference in efficiency can be reduced. Therefore, the common electrode reinforcing pattern 4 provided for the purpose of lowering the resistance value of the common electrode can be omitted, and the manufacturing process can be shortened. FIG.
FIG. 4 is a manufacturing process diagram illustrating a manufacturing process of the heating element substrate according to the present embodiment. Another advantage of omitting the common electrode reinforcement pattern is that the record after coloring can be seen immediately after printing.

Embodiment 5 FIG. FIG. 19 shows the fourth embodiment shown in FIG.
In this case, the width of the extended common electrode lead 1 is increased to reduce the voltage drop due to the electric resistance of the common electrode lead.

Embodiment 6 FIG. In the sixth embodiment shown in FIG. 20 or FIG. 21, at least one of the common electrode lead 1 and the individual electrode lead 2 facing each other at the position of the heating resistor 62 having a small width is provided with a convex portion. . In this case, when the heating resistor 62 is insulated by open trimming, the portion where the electrode interval is narrowed by the convex portion generates heat preferentially. Cracks can be created stably. As a result, troubles such as cracks becoming too large and the heating resistor being burned and scattered can be avoided, and stable and uniform production becomes possible. Although the shape of the convex portion is not particularly limited, FIG.
The effect of Example 1 was greater than that of Example 1.

Embodiment 7 FIG. In a seventh embodiment shown in FIG. 22, a strip-shaped ridge 10 is provided on an insulating substrate 9 supporting a heating element,
The common electrode lead 1, the individual electrode lead 2, and the heating resistor 5 are mounted thereon. FIG. 23 shows FIG.
It is sectional drawing of AB position of. The insulating substrate 9 is made of, for example, alumina, and the raised portion 10 is formed in a semicircular cross section by, for example, printing, drying, and firing a glass paste. 11
Is a protective film formed by printing, drying and baking a glass paste, for example, to protect the heating resistor 5, 12 is a recording paper which is a thermal paper, 13 is an elastic body, and is a platen which rotates and transports the recording paper 12. Roller. F (arrow) indicates a pressing force for pressing the thermal head against the platen roller. When the raised portion is provided on the insulating substrate in this manner, the pressing force of the thermal head is concentrated on the heating resistor 5, so that a high coloring efficiency can be obtained even with a small pressing force. FIG.
FIG. 4 shows the relationship between the pressing force of the thermal head and the coloring efficiency in comparison with Example 1 in FIG. The energy of the applied pulse is 0.3 mJ. Under the condition of pressing force 100g / cm,
The coloring efficiency of the first embodiment (FIG. 1) is about 50%, while the coloring efficiency of the present embodiment is about 90%. Even with the same pressing force, a higher coloring efficiency is obtained in this embodiment. In the present embodiment, the pressing force required to obtain the same coloring efficiency can be reduced by about 30%.

Embodiment 8 FIG. In the eighth embodiment shown in FIG. 25, the heat generating resistor of the thermal head according to the present invention can be made by a thin film forming process. FIG. 25A is a manufacturing process diagram showing the manufacturing process, and FIG. 25B is a plan view of the heating element, and FIG. 25C is a cross-sectional view taken along a line AB in the plan view. 26A and 26B are a manufacturing process diagram (A) and a plan view (B) of a heating element of a conventional thin film thermal head shown for comparison.
When the heating resistor is formed by a thin film forming process, the thickness of the resistor is, for example, 0.1 to 0.3 μm, which is smaller than the thickness of the conductor film for an electrode, for example, 1 to 1.5 μm. Therefore, when the resistor is formed on the electrode, there is a disadvantage that the resistor film is not formed at the end of the electrode. Therefore, in the manufacturing process of this embodiment, as shown in FIG. 25A, the resistor is formed before the conductive film for the electrode, and thus in the lower layer. FIG.
FIG. 4 shows a change in resistance value of the heating resistor formed by the thin film forming process due to application of an electric pulse. The material of the resistor film by a thin film forming process for example T _a and S _i O
Cermet or polycrystalline S _i such comprising _two is used. R _d At a 27 cermet resistor, R _u shows the characteristics of the polycrystalline S _i resistor. At the pulse application energies E ₁ and E ₂ , both R _U and R _d are broken, resulting in disconnection. Therefore, open trimming can be performed in the same manner as in the case of the thick film resistor. However, it is difficult to perform pulse trimming for uniformly adjusting the resistance value. This is because the area where the resistance value can be adjusted is narrower than the characteristic shown in FIG. 33 in the case of a thick film resistor. In the manufacturing process of the present embodiment shown in FIG. 25A, the step of forming the pattern of the heating resistor can be omitted and the process can be simplified as compared with the conventional manufacturing process of the thin-film thermal head shown in FIG. There is.

Embodiment 9 FIG. In this embodiment, the composition ratio of the thick film resistor paste is set to a value suitable for open trimming and pulse trimming. FIG. 28 shows zirconia,
This graph shows the relationship between the pulse applied voltage and the change in resistance value when the component ratio of zirconia (however, the weight ratio after firing) is changed in a thick film resistor paste composed of ruthenium oxide and a glass component. Conditions for easier both open trimming and pulse crop during the applied voltage from V _O At a 28 to V _L is the resistance value decreases gradually, and Zoka rapidly resistance value is more than V _L applied voltage V _D required for the insulated is the low. Zirconia component ratio 5% 28, the V _D corresponding to 10%, such as V _D5, V
It is written like _D10 . According to experiments, V _L is 60V, V _D5
Is 65V, V _D10 is 70V, V _D15 is 120V, V _D20 150
V. Since V _D is sharply increases when the zirconia component ratio exceeds 10%, the zirconia component ratio from this point is preferably 10% or less. On the other hand, the purpose of mixing zirconia is to improve the long-term stability of the heating resistor. However, in the thermal head according to the present invention, the pulse application energy during normal use can be reduced, so that the long-term stability is good. Was found to be 10% or less. Considering the above two points, the preferable range of the zirconia component ratio in the thermal head of the present invention is 10%.
It was as follows.

Embodiment 10 FIG. In this embodiment, the thickness of the thick-film heating resistor is set to a value suitable for the manufacturing process of the thermal head according to the present invention. FIG. 29 shows the relationship between the thickness of the resistor after firing and the pulse application voltage necessary to insulate the resistor during open trimming. When the thickness of the resistor is in the range of 1 to 4 μm, the required applied voltage changes substantially linearly with respect to the thickness of the resistor, and the variation is small. Trimming becomes difficult, and conversely, if it is 1 μm or less, the variation in the required applied voltage increases, and stable production becomes difficult. The minimum thickness that can be manufactured stably from the viewpoint of manufacturing tolerance is about 1 μm. In consideration of the above, the preferable range of the thickness of the thick-film heating resistor in the manufacturing process is set to 1 to 4 μm after firing.

[0051]

The thermal head according to the first aspect of the present invention
A common electrode, a plurality of common electrode leads continuously connected to the common electrode in a comb shape, and a gap between one adjacent common electrode lead is smaller than a gap between the other common electrode lead. and the common electrode lead between the plurality of individual electrode leads respectively provided, a heating resistor disposed over on these individual electrode lead and the common electrode leads, and the individual electrode leads in the heating resistor
On the side where the distance from this individual electrode lead becomes narrower
A protrusion connected to the individual electrode lead or the one common electrode lead between the one common electrode lead and the individual electrode lead and the one common electrode via the protrusion when voltage is applied; Form an insulator between the lead and the space between the individual electrode lead and the individual electrode lead.
With the other common electrode lead located on the side where
Since a heating element is formed therebetween, when a voltage is applied between the individual electrode lead and the one common electrode lead, priority is given to the vicinity of the projection connected to the individual electrode lead or the one common electrode lead. As a result, an insulator can be stably formed between the individual electrode lead and one of the common electrode leads.

In the thermal head according to the second aspect of the present invention, the gap between the common electrode, a plurality of common electrode leads connected to the common electrode in a comb shape, and one adjacent common electrode lead is formed on the other side. A plurality of individual electrode leads respectively provided between the common electrode leads so as to be narrower than a gap with the common electrode lead, and these individual electrode leads and
The part for the narrow interval that straddles the common electrode lead
Heating resistor with insulating or high resistance components
For example, across the heating resistor provided oppositely disposed conductor portions to the common electrode, electrically to the conductor portion of the predetermined common electrode leads of the common electrode lead extend beyond the heating resistor Since the voltage drop caused by the voltage resistance of the common electrode can be reduced,
The difference in the coloring efficiency of the heating resistor can be reduced.

The thermal head according to the third aspect of the present invention
Make the width of the common electrode lead larger than the width of the individual electrode leads.
Because of widening, it is caused by the voltage resistance of the common electrode
The voltage drop can be further reduced.

The thermal head according to the fourth aspect of the present invention
The heating resistor contains zirconia, and its mass component ratio is
10% or less, the individual electrode lead and the one
Required to form an insulator between the common electrode lead
Applied voltage can be reduced.

The thermal head according to the fifth aspect of the present invention
Since the thickness of the heating resistor is 1 μm to 4 μm,
Between the individual electrode lead and one of the common electrode leads.
Suppress variations in the overprint voltage required to form the insulator
The thermal head can be manufactured stably.
Can be.

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[Brief description of the drawings]

FIG. 1 is a plan view showing a heating element according to Embodiment 1 of the present invention.

FIG. 2 is a diagram showing a relationship between a width of a heating resistor and an applied pulse voltage required for destruction.

FIG. 3 is a diagram showing a relationship between resistance values of two heating resistors of the heating element according to the present invention and an applied pulse voltage.

FIG. 4 is a manufacturing process diagram showing a manufacturing process according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram illustrating a temperature distribution at the time of heat generation of the heating element according to the first embodiment of the present invention.

FIG. 6 is a diagram showing a relationship between a print dot size and an applied pulse energy of a conventional thick film thermal head.

FIG. 7 is a diagram illustrating a relationship between a print dot size and an applied pulse energy according to the first embodiment of the present invention.

FIG. 8 is a diagram showing the relationship between the print dot size and the applied pulse energy of a conventional thick film thermal head.

FIG. 9 is a diagram illustrating a relationship between a print dot size and applied pulse energy according to the first embodiment of the present invention.

FIG. 10 is a diagram showing the relationship between the coloring efficiency and applied pulse energy of a conventional thick film thermal head.

FIG. 11 is a diagram showing the relationship between the coloring efficiency and the applied pulse energy according to the first embodiment of the present invention.

FIG. 12 is a plan view showing a heating element according to Embodiment 2 of the present invention.

FIG. 13 is a plan view showing a heating element according to Embodiment 2 of the present invention.

FIG. 14 is a plan view showing a heating element according to Embodiment 2 of the present invention.

FIG. 15 is a plan view showing a heating element according to Embodiment 3 of the present invention.

FIG. 16 is a plan view showing a heating element according to Embodiment 3 of the present invention.

FIG. 17 is a plan view showing a heating element according to Embodiment 4 of the present invention.

FIG. 18 is a manufacturing step diagram showing a manufacturing process according to Example 4 of the present invention.

FIG. 19 is a plan view showing a heating element according to Embodiment 5 of the present invention.

FIG. 20 is a plan view showing a heating element according to Embodiment 6 of the present invention.

FIG. 21 is a plan view showing a heating element according to Embodiment 6 of the present invention.

FIG. 22 is a perspective view showing a heating element according to Embodiment 7 of the present invention.

FIG. 23 is a sectional view showing a heating element according to Embodiment 7 of the present invention.

FIG. 24 is a diagram showing the relationship between the coloring efficiency and the pressing force of the thermal head according to the seventh embodiment of the present invention in comparison with the first embodiment.

FIG. 25 is a manufacturing step diagram showing the manufacturing process of the eighth embodiment of the present invention.

FIG. 26 is a manufacturing process diagram showing a manufacturing process of a conventional thin film thermal head.

FIG. 27 is a diagram showing a relationship between a resistance value of a thin-film heating resistor and applied pulse energy.

FIG. 28 is a view showing the relationship between the resistance value and the applied pulse voltage when the composition ratio of the thick-film heating resistor is changed.

FIG. 29 is a diagram showing the relationship between the thickness of a thick-film heating resistor and an applied pulse voltage that causes destruction.

FIG. 30 is a plan view showing a heating element of a conventional thick film thermal head.

FIG. 31 is a manufacturing process diagram showing a manufacturing process of a heating element of a conventional thick film thermal head.

FIG. 32 is an explanatory diagram showing a temperature distribution at the time of heat generation of a conventional thick film heating resistor.

FIG. 33 is a diagram showing a relationship between a pulse voltage applied to a thick-film heating resistor and a change in resistance value.

FIG. 34 is a diagram illustrating a change in resistance value when a plurality of voltage pulses are applied to a thick-film heating resistor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Common electrode lead 2 Individual electrode lead 3 Common electrode 4 Common electrode reinforcement pattern 5 Heating resistor 6 Heating element 61, 62 Two heating resistors constituting one heating element 8 Insulator 9 Insulating substrate 10 Rising portion of insulating substrate 11 Protective film of heating resistor 12 Recording paper 13 Platen roller

Claims (5)

(57) [Claims] 1. A gap between a common electrode, a plurality of common electrode leads continuously connected to the common electrode in a comb shape, and a gap between one adjacent common electrode lead and a gap between the other common electrode lead. a plurality of individual electrode leads respectively provided between the common electrode leads to be narrowed, and the heating resistor provided over on these individual electrode lead and the common electrode lead, the in the heating resistor Pieces
The distance between another electrode lead and this individual electrode lead becomes narrower
A protruding portion connected to the individual electrode lead or the one common electrode lead between the one common electrode lead positioned on one side, and the individual electrode lead and the An insulator is formed between one common electrode lead and the individual electrode lead and the individual electrode lead.
The other common electrode located on the side where the distance from the gate is wider
A thermal head , wherein a heating element is formed between the lead . 2. A gap between a common electrode, a plurality of common electrode leads connected to the common electrode in a comb shape, and a gap between one adjacent common electrode lead and a gap between the other common electrode lead. a plurality of individual electrode leads respectively provided between the common electrode leads so also narrowed, these pieces
Straddle the separate electrode lead and the common electrode lead, and
Parts with insulation or high resistance
A heat conductor, and a conductor portion disposed opposite to the common electrode with the heat resistor interposed therebetween, and extending a predetermined common electrode lead out of the common electrode lead beyond the heat resistor. A thermal head electrically connected to a conductor. 3. The claim 1, characterized in that the width of the common electrode lead was wider than the width of the individual electrode lead
Is the thermal head described in 2 . 4. The heating resistor includes zirconia,
請 that the weight component ratio is equal to or less than 10%
3. The thermal head according to claim 1 or 2 . 5. A heating resistor having a thickness of 1 μm to 4 μm.
3. Therma according to claim 1 , wherein m is m.
Head .