JPS61121965A - Thermal head - Google Patents

Abstract

PURPOSE:To enable printing at a printing dot cycle of 0.9-0.6msec, by forming a glaze layer having a protruded shape with a height of 70-120Xm, a heat generating resistor comprising Ni-Cr, a conductor and a protective layer to a substrate. CONSTITUTION:When printing is performed, voltage is generated between conductors 4a, 4b at first and resistance coefficient is stable within a range of -3-3ppm/ deg.C and, when printing is performed at a printing dot cycle of 0.9-0.6msec, a current is flowed to a heat generating resistor 7 using Ni-Cr, of which the resistance value is stable even if the surface temp. of a thermal head reaches 600-700 deg.C and the heat generating resistor 7 generates heat. In this case, because the height of the protruded shape of the glaze layer 2a is set to a high value of 70-120mum, the heat generated from the heat generating resistor 7 is accumulated and the accumulated heat is utilized in printing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a thermal printing device and a thermal transfer printing device.

Conventional configurations and their problems In recent years, printing devices have become widespread, and in particular, non-impact type thermal 2-beam printing devices and thermal transfer printing devices, which have low printing noise during printing, are attracting attention. A thermal head is used in this section.

The conventional thermal head as described above will be described below with reference to the drawings.

In Figure 1, 1 is an alumina substrate, 2 is an alumina substrate 1
3 is a heating resistor formed on the glaze layer 2 and the alumina substrate 1; 4a and 4b are heating resistors 3 formed on the glaze layer in the shape of a protrusion partially formed thereon; A conductor for generating heat, 5 is a heating resistor 3
and an oxidation-resistant layer formed on the conductors 4a, 4bJ1, 6
is a wear-resistant layer formed on the oxidation-resistant layer 6''.

This conventional thermal head is made of T a 2 N (tantalum nitride) as a commonly used heating resistor, 5 inch (-silicon oxide) and SiO2 as an oxidation-resistant layer.
(silicon dioxide) and Ta206 (tantalum pentoxide) as the wear-resistant layer. Further, the height of the protrusion shape of the glaze layer is 40/jm-ωltm. The thermal head with these configurations can print 3-page dots with a period of 2.4 m5eC to 1.2771 SeC.
When printing at low speed printing, the energy required to be applied to the thermal head to be able to print characters is 0
．． 4mj, the surface temperature of the thermal head at that time is as low as 3ec.degree. C. to 400.degree. C., and the life of the thermal head is 1.times.10@8 pulses or more. However, when printing at high speed with a printing dot period of 0.9m5ec-0.6m5eC, the energy required to be applied to the thermal head when it becomes possible to print characters is 0.6mj or more, and the surface of the thermal head at that time The temperature is also 600℃ ~
Due to the high temperature of 700℃, cracks in the heating resistor and peeling of the oxidation-resistant layer and wear-resistant layer occur, and the lifespan of the thermal head becomes less than 1 x 107 pulses, which means that the thermal head that can normally be used is Since it does not satisfy the lifespan of 1×1o8 pulses or more, it has the disadvantage that high-speed printing cannot be put to practical use.

Purpose of the Invention In view of the above-mentioned drawbacks, the present invention provides a printing dot period of 0.9 m5.
eC-0,6m5eC(7) printing is possible and 1×1
Do you offer thermal heads with a lifespan longer than 08 pulses? A. Structure of the Invention In order to achieve this object, the thermal head of the present invention has a glaze layer in which the height of the protrusions of the glaze layer partially formed on the substrate is 7 μm to 120 μm, and the heating resistor is The body material is Ni-Cr (nickel chromium).

With this configuration, the temperature coefficient of resistance of the heating resistor using Ni-Cr (nickel chrome) is -3 pprry'C.
The resistance value of the heating resistor is stable at ~3 ppm/°C, and even when the surface temperature of the thermal head reaches 550°C to 660°C. In addition, the heat generated by the heating resistor is stored in the glaze layer whose height is 70/1 m to 120/Am, and the dot period is 0.9 m5IX: ~Q,5 The applied energy required to print @ See is 0.4 m i -0.5 m
decreases to j. Therefore, the printing dot period Q, 9771Se
When printing C-Q and 13 m5ec, it is possible to provide a 6-vane thermal head whose life span is 1×108 pulses or more.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows a sectional view of a thermal head in an embodiment of the present invention.

In FIG. 2, 1 is an alumina substrate, 2a is a glaze layer with a convex projection shape having a height of 7 μm to 120 μm, and 7 is an N
4a and 4b are conductors, and 8 is a protective film.

The operation of the thermal head configured as described above will be explained below. When printing, a voltage is first generated between the conductors 4a and 4b, and the resistance coefficient is 13pp.
When printing at a stable temperature of m/℃ to 3pprrV/℃ and a printing dot period of 0.9 @SeC-0,6@SeC, even if the surface temperature of the thermal head reaches a high temperature of 600℃ to 700℃. A current flows through the heat generating resistor 7, which is made of Ni-Cr (nickel chrome) with a stable resistance value, and the heat generating resistor 7 generates heat.

Next, the heat generated from the heat generating resistor 7 is divided into two parts: one is conducted to the protective film 8 to page 6 and toward the surface of the recording paper, and the other is conducted to the glaze layer 2a and then to the alumina substrate 1. However, the height of the convex protrusion shape of glaze layer 2& is 70
Since the diameter is as high as μm to 120 μm, the heat generated from the heating resistor 7 is stored in the glaze layer 2a, and the stored heat is used for printing. Therefore, the printing dot period is 0.9 m5ec-0
, the applied energy required for printing 6TrLSeC is 0.4
m 1-o, 5m j, and the life of the thermal head can also be satisfied at 1×10 8 pulses or more.

FIG. 3 shows the results of a thermal head life test at a printing dot period Q and 9771 SeC. The horizontal axis shows the energy applied to the thermal head, and the vertical axis shows the thermal head life pulse. A shows the lifespan of the thermal head of the present invention, and b shows the lifespan of the conventional thermal head. From this figure, it can be seen that the life of the thermal head of the present invention is much longer than that of the conventional thermal head.

In this embodiment, one layer of protective film is used for the heating resistor and the conductor, but it may be formed of two layers: an oxidation-resistant layer and an abrasion-resistant layer.

Effects of the Invention As described in ``2'', the present invention increases the height of the protrusions of the glaze layer and uses Ni-Cr (nickel chromium) as the heating resistor material, so that the printing dot period can be reduced to 0.
．． It is possible to provide a thermal head that can print at 9 m5eC-0 and 6m5eC with low applied energy and has a lifespan of 1 x 108 pulses or more, and its practical effects are impressive.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional thermal head, FIG. 2 is a sectional view of a thermal head according to an embodiment of the present invention, and FIG. 3 is a characteristic diagram for explaining the present invention in detail. 1... Alumina substrate, 2a... Glaze layer, 4a, 4b... Conductor, 7...
Heat generating resistor (Ni-Cr), 8... protection. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 ρ

Claims (1)

[Claims] a protrusion-shaped glaze layer partially formed on the substrate;
A heating resistor selectively formed on the glaze layer and the substrate; a conductor formed on the heating resistor for causing the heating resistor to generate heat; and a conductor formed on the heating resistor and the conductor. a protective film formed on the glaze layer, and the height of the protrusion shape of the glaze layer is 70 μm to 120 μm,
A thermal head characterized in that Ni-Cr (nickel chromium) is used as the heating resistor material.