JPS61219104A - Thermal recording head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermal recording head used in a recording method that performs recording using thermal energy.

[Prior Art] Traditionally, recording methods that use thermal energy have the advantage of being non-impact and therefore producing very little noise during recording, and in recent years have also become capable of color recording. It is gradually attracting attention.

In such a recording method, recorded information is transmitted in the form of an electrical signal to a thermal recording head, that is, an electrothermal conversion element. The electro-thermal conversion element used includes a heat generating resistance layer formed on a base and at least one pair of electrodes connected to the heat generating resistance layer.

Here, the term "substrate" refers to one that supports a heat generating resistive layer, and the substrate is simply a support with appropriate layers formed thereon, if necessary. Since thermal recording heads are generally relatively small, their heating resistance layers are of a thin film type, a thick film type, or a semiconductor type. especially,
Thin-film types consume less power than other types, and have relatively good thermal response, making them ideal for thermal recording.

It is preferable as a component of a card, and its application is gradually increasing.

Therefore, the performance required of the heat generating resistive layer of a thermal recording head is good responsiveness of heat generation to a predetermined electric signal, good thermal conductivity, and good heat resistance against its own heat generation. and that various types of durability (for example, durability against thermal history) are good. Furthermore, when the thermal recording head is used in pressure contact with thermal paper or thermal transfer ink ribbon, it is required that the coefficient of friction with these is small.

However, it cannot be said that the above performance is necessarily satisfactory in the heat generating resistive layer of the conventionally used thermal recording head, and further improvement of the characteristics is desired.

Furthermore, in conventional thermal recording heads, a wear-resistant layer is provided on the surface of the heat-generating resistor layer in order to improve wear resistance, but this comes at the expense of thermal responsiveness.

In addition, with conventional thermal recording heads, when recording on a recording medium with a rough surface, such as paper, it is necessary to press the recording medium more firmly in order to record in a perfect dot shape, which reduces the rate of wear. There is a desire for further improvement in performance.

[Object of the invention] In view of the above-mentioned prior art, one of the objects of the present invention
One object of the present invention is to provide a thermal recording head having a heat generating resistive layer with improved thermal responsiveness.

Another object of the present invention is to provide a thermal recording head having a heating resistance layer with improved thermal conductivity.

Still another object of the present invention is to provide a thermal recording head having a heating resistance layer with improved heat resistance.

Another object of the present invention is to provide a thermal recording head having a heat generating resistive layer with improved durability.

Another object of the present invention is to provide a thermal recording head having a heating resistance layer with improved wear resistance.

Still another object of the present invention is to provide a thermal recording head having a heat generating resistance layer with a small coefficient of friction.

SUMMARY OF THE INVENTION The above objects are achieved by a novel thermal recording head according to the present invention.

The thermal recording head of the present invention is characterized in that the heat generating resistive layer is made of an amorphous material having carbon atoms as a matrix and containing germanium atoms, halogen atoms, and hydrogen atoms.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a partial plan view showing the structure of an embodiment of the thermal recording head of the present invention, and FIG. 2 is a sectional view taken along the line 1--2.

In the figure, 2 is a support (substrate here), 4 is a heating resistance layer, and 6.7 is a pair of electrodes. 1st
As shown in the figure, a plurality of pairs of a heating resistor layer 4 and a pair of electrodes 6.7 connected to the heating resistor layer 4 are provided, thereby forming dot-shaped effective heating parts 8, 8'. ,8″,
φ... are arranged on a straight line at predetermined intervals. When the thermal recording head is in use, the heating resistance layer 4 side is brought into pressure contact with thermal paper or thermal transfer ink ribbon, etc., and is moved relative to the thermal paper or thermal transfer ink ribbon in the II-11 direction. At this time, an electric signal, which is recorded information, is timely applied to the heat generating resistor layer 4 constituting each heat generating section 8.8', 8'', . . . through the electrode 6.7, and based on this, each heat generating section Heat is generated, and the thermal energy at this time is used to perform recording using a thermal method, a thermal transfer method, or the like.

In the present invention, there is no particular restriction on the material of the support 2, but in practice it has good adhesion to the heating resistor layer 4 and the electrodes 6.7 formed on its surface. It is preferable to use a material that has good durability against the heat generated during the formation of the electrodes 6 and 7 and the heat generated by the heat generating resistor layer 4 during use.

The support 2 also has a heating resistance layer 4 formed on its surface.
It is preferable to have an electrical resistance larger than that of the support 2. Furthermore, a material is selected for the support 2 that has thermal conductivity that allows necessary and sufficient thermal energy to be applied to the recording medium side and that does not deteriorate responsiveness to electrical input. .

Examples of the support 2 used in the present invention include those made of inorganic materials such as glass, ceramics, and silicon, and those made of organic materials such as polyamide resin and polyimide resin.

In the present invention, the heating resistance layer 4 is made of an amorphous material having carbon atoms as its base material and containing germanium atoms, halogen atoms, and hydrogen atoms. F as a halogen atom,
C1, Br, 'I, etc. can be used, and these may be used alone or in a combination of N numbers. As the halogen atom, especially F
, C1 are preferred, and F is especially preferred.

The content rate of germanium atoms in the heating resistance layer 4 is
It is appropriately selected so as to obtain the desired properties, but is preferably 0.0001 to 40 atom%, more preferably 0.0001 to 40 atom%.
．． 0005 to 20 at%, preferably 0.001-
It is 10 atom%.

The content of halogen atoms in the heating resistance layer 4 is appropriately selected so as to obtain desired characteristics, but is preferably o.
-ooot to 30 atom%, more preferably 0.0
005 to 20 atomic %, preferably o, oot to 10
It is atomic percent.

The content of hydrogen atoms in the heating resistance layer 4 is appropriately selected so as to obtain desired characteristics, but is preferably 0.0.
001 to 30 at%, more preferably 0.000
The content is 5 to 20 atom %, preferably 0.001 to 10 atom %.

The sum of the germanium atom content, halogen atom content, and hydrogen atom content in the heating resistance layer 4 is appropriately selected so as to obtain desired characteristics, but is preferably 0.
．． 0001 to 40 atomic%, more preferably o, o
oos~30 M%, preferably 0.001~20
It is atomic percent.

In the thermal recording head of the present invention, an amorphous material (hereinafter sometimes abbreviated as ra-C:Ge:(X,H)J) is formed of carbon as a matrix and contains germanium atoms, halogen atoms, and hydrogen atoms. The heat-generating resistor layer 4 made of (herein, halogen atoms) is formed by, for example, a plasma fcVD method such as a glow discharge method, or a vacuum deposition method such as a sputtering method.

For example, a-C:Ge:(X
, H), basically the base 2 is placed in a deposition chamber under reduced pressure, and a raw material gas for C supply that can supply carbon atoms (C) into the deposition chamber is added. A raw material gas for Ge supply that can supply germanium atoms (Ge), a raw material gas for X supply that can supply halogen atoms (X), and a raw material gas for H supply that can supply hydrogen atoms (I). Introduce it.

A glow discharge is generated in the deposition chamber using high frequency or microwave, and a-C:Ge:(X,
A layer consisting of H) may be formed.

In addition, a-C:Ge:(X
, H), basically, the substrate 2 is placed in a deposition chamber under reduced pressure, and an inert gas such as Ar, He, etc. or a base gas of these gases is injected in the deposition chamber. When sputtering a target made of C in a mixed gas atmosphere, it is sufficient to introduce a source gas for Ge supply, a source gas for X supply, and a source gas for H supply into the deposition chamber.

In the above method, as the raw material gas for C supply, the raw material gas for Ge supply, the raw material gas for X supply, and the raw material gas for H supply, in addition to those in a gas state at room temperature and normal pressure, substances that can be gasified under reduced pressure are used. can be used.

Examples of raw materials for supplying C include saturated hydrocarbons having 1 to 5 carbon atoms, ethylene hydrocarbons having 2 to 5 carbon atoms, and acetylene hydrocarbons having 2 to 4 carbon atoms.

Aromatic hydrocarbons, etc., specifically saturated hydrocarbons include methane (CH4), ethane (C2Ha), propylene (
C3Ha), n-buta7 (n-C4H1o), pentane (C5H12), ethylene hydrocarbons include ethylene (C2H4), propylene (C3He),
Butene-1 (C4H8), Butene-2 (C4Ha)
, inbutylene (C4H8), pentene (C5HI
O), acetylene (C
2H2), methylacetylene (03H4), butyne (C4Hs), and aromatic hydrocarbons such as benzene (
Cs Ha ), etc.

Examples of raw materials for supplying Ge include GeH4, Ge2
Ha, Ge3 HB, Ge41 (10, G
C5H12,G C6H14,G C7H16,G e
Germanium hydride such as BHlB and Ge9H20.

GeF4, (GeF2)s, (GeF2)s, (GeF
2) 4, Ge2 F6, Ge3 FB, GeH
F3, CCl2 F2, GeC14 (GeC12)
5. GeBr4. (GeBr2)s, Ge2 C1B
, Ge2 C13F3, and other germanium halides (hydrogen halide derivatives substituted with halogen atoms).

As a raw material for supplying X, for example, halogen.

Examples of halogens include halides, interhalogen compounds, halogen-substituted hydrocarbon derivatives, and specifically F2. C12
, Br2. I2. HF, HCl as halides
, HBr, HI, interhalogen compounds include BrF, C
IF, ClF3, BrF5, BrF3. IF3,
IF7, IC1, IBr, halogen-substituted hydrocarbon derivatives include CF4, CHF3, CH2F2, CH
3F, CCl4, CHCl3, CH2C12, CH2
O1, CB F4, CHB F3, CH2B F
2, CH3Br, Cl4. CHI3, CH2I2
.

Examples include CH3I.

Examples of raw materials for supplying H include hydrogen gas and hydrocarbons such as saturated hydrocarbons, ethylene hydrocarbons, acetylene hydrocarbons, and aromatic hydrocarbons, which are also the raw materials for supplying C.

These raw materials may be used alone or in combination.

In the heating resistance layer forming method as described above, in order to control the amount of germanium atoms, the amount of halogen atoms, the amount of hydrogen atoms and the characteristics of the resistance layer 4 contained in the resistance layer 4 to be formed, the substrate temperature, The supply amount of raw material gas, discharge power, pressure inside the deposition chamber, etc. are set appropriately.

The substrate temperature is preferably selected from 20 to 1500°C, more preferably 30 to 1200°C, and optimally 50 to 1100°C.

The supply amount of the raw material gas is determined as appropriate depending on the desired performance of the heating resistance layer and the desired film formation rate.

Discharge power is preferably 0.001 to 20W/crn'
, more preferably 0.0l-15W/cm', optimally 0.05-10W/cm'+7).

The pressure inside the deposition chamber is preferably to-4 to 10 Torr.
, more preferably 10-2 to 5 Torr.

The resistive layer of the thermal recording head of the present invention obtained using the heat generating resistive layer forming method as described above has properties close to those of diamond. That is, for example, Vickers hardness of 1800 to 5000,
Thermal conductivity 0.3-2 cal/cm @sec
* "Cj, resistivity 105~1011Ω・cm, coefficient of thermal expansion 2X10-5~10-6/'C!, coefficient of friction 0.15
~0.25, density 1.5~3.0, and contains germanium atoms, norogen atoms, and hydrogen atoms, so it has extremely good flexibility.

In the thermal recording head of the present invention, the resistance layer 4 has particularly good abrasion resistance, so the resistance layer can be made extremely thin, and a special abrasion resistant layer is not required, resulting in extremely good thermal response. you can get something.

However, it goes without saying that a layer having appropriate protection and other functions may be provided on the heating resistance layer 4 of the thermal recording head of the present invention. For example, by providing a protective layer, even more durability can be achieved. You can make improvements.

In the embodiments described above, an example is shown in which the heating resistance layer and the electrode are provided on the substrate in this order, but in the thermal recording head of the present invention, the electrode and the heating resistance layer may be provided on the substrate in this order. FIG. 3 is a partial sectional view of such a thermal recording head. In FIG. 0, 2 is a support (substrate here).
4 is a heating resistance layer, and 6.7 is a pair of electrodes.

In this case, since the more durable heat-generating resistive layer is placed on the recording medium side, an extremely excellent thermal recording head can be provided even without providing a wear-resistant layer.

In the above embodiments, the base is simply a support 2.
However, in the present invention. The substrate may be a composite, and the configuration of one such example embodiment is described in the fourth section.
As shown in the figure, the base 2 is made of a composite of a support 2a and a surface layer 2b, and the support 2a includes, for example, the first layer described above.
The support materials described in connection with the figures and even metals can be used.

The surface layer 2b may be made of a material that has better adhesion to the resistance layer 4 formed thereon. It is composed of oxides etc. Such a surface layer 2b can be obtained by depositing appropriate raw materials on the support 2a by a method similar to the above-mentioned method for forming the heating resistor layer. Also, the surface layer? b may be a normal glassy glaze layer.

The electrodes 6.7 in the thermal recording head of the present invention may be of any material as long as they have a predetermined conductivity, such as Au, Cu,
A1. Made of metal such as Ag and Ni.

Next, an outline of a method for manufacturing a thermal recording head according to the present invention will be explained.

FIG. 5 is a diagram showing an example of an apparatus used when forming a heating resistance layer on the surface of a substrate. 1101 is a deposition chamber, and 1102 to 1106 are gas cylinders! J, 110
7 to 1111 (i mass flow controller, 11
12-1116 are inflow valves, 1117-112
1 is an outflow valve, 1122 to 1126 are gas cylinder valves, 1127 to 1131 are outlet pressure gauges, 1132 is an auxiliary valve, 1133 is a lever, 1134 is a main valve, and 1135 is a leakage valve. 1136 is a vacuum gauge, 11 is a valve, and 1136 is a vacuum gauge;
37 is the base material of the thermal head to be manufactured;
13 is a heater, 1139 is a substrate support means, 1140 is a high voltage power supply, 1141 is an electrode, and 1142 is a shutter. Note that 1142-1 is a target attached to the electrode 1141 when performing the spar two tarring method.

For example, 1102 is sealed with CF4 gas (99.9% purity or higher) diluted with Ar gas, and 1103
C2F6 gas (purity 99.9
% or more) is sealed, and 1104 is sealed with GeH4 gas (purity of 99.9% or more) diluted with Ar gas.

Before the gas in these cylinders flows into the deposition chamber 1101, the valves 11 of each gas cylinder 1102 to 1106
22-1126 and leak valve 1135 are closed, and inlet valves 1112-1116
, outflow valves 1117-1121 and auxiliary valve 113
Make sure that valve 2 is open, then open main valve 1 first.
134 is opened to exhaust the inside of the deposition chamber 1101 and gas piping.

Next, the reading of vacuum gauge 1136 is about 1.5XIO-6Tor.
At the point where it becomes r, auxiliary valve 1132° inflow valve 1
112-1118 and outflow valves 1117-1121 are closed. Thereafter, a valve of a gas pipe connected to a cylinder of gas to be introduced into the deposition chamber 1101 is opened to introduce a desired gas into the deposition chamber 1101.

Next, an example of the procedure for forming the resistive layer of the thermal recording head of the present invention by the glow discharge method using the above-described apparatus will be described. Open valve 1122 and gas pump 11
CF, /Ar gas flows out from valve 1124.
Open the gas pump 1104 to let GeH4/Ar gas flow out, and set the pressure on the outlet pressure gauge 1127 and 1129 to x.
kg/cm', then inlet valve 1112.11
14 gradually opens the mass flow controller 1107.
1109, and then the outflow valve 11.
17.1119, gradually open the auxiliary valve 1132 and
F4/Ar gas and GeH4/Ar gas are deposited in the deposition chamber 110.
Introduced within 1. At this time, the flow rate of CF4/Ar gas and G
Adjust the mass flow controllers 1107 and 1119 so that the ratio of the eH4/Ar gas flow rate reaches the desired value, and adjust the main flow while watching the vacuum gauge 1136 so that the pressure inside the deposition chamber 1101 reaches the desired value. Adjust the opening degree of valve 1134. And the support body 113 in the deposition chamber 1101
After heating the substrate 1137 supported by the substrate 1137 by the heater 1138 to a desired temperature, the shutter 1142 is opened to generate a glow discharge in the deposition chamber 1101.

Next, an example of the procedure for forming the resistive layer of the thermal recording head of the present invention by sputtering using the above-described apparatus will be described. On the electrode 1141 to which a high voltage is applied by the high voltage power supply 1140, a high purity graphite
142-1 as a target, and CF from gas pump 1102 in the same manner as in the glow discharge method.
4/Ar gas from the gas pump 1104 to GeH+/Ar
Each gas is introduced into the deposition chamber 1101 at a desired flow rate. Open the shutter 142 and turn on the high voltage power supply 1140.
1142-1 is sputtered. At this time, the heater 1138 is used to heat the base 1.
137 to a desired temperature and adjusting the opening degree of the main valve 1134 to bring the inside of the deposition chamber 1101 to a desired pressure is similar to the glow discharge method.

In the case of a thermal recording head as shown in FIGS. 1 and 2, the formation of the heat generating resistive layer on the substrate by the glow discharge method and sputtering method as described above is carried out over almost the entire surface of the substrate. Thereafter, by forming a conductive layer and etching the conductive layer and heat generating resistive layer using photolithography, a thermal recording head having a plurality of dot-shaped effective heat generating parts as shown in FIG. 1 can be obtained. .

Furthermore, in the case of a thermal recording head as shown in Fig. 3,
After forming a conductive layer on a substrate in advance and etching the conductive layer using photolithography, a heat generating resistive layer is formed on the substrate by the glow discharge method and sputtering method as described above.

Specific examples of the thermal recording head of the present invention are shown below.

Example 1: A glaze layer was provided on a support made of an alumina ceramic plate as a base, and a heat generating resistor layer was formed on the surface of the base. The deposition of a heat generating resistor layer was shown in FIG. The method was carried out using a glow discharge method using a device similar to the one described above. CF4/Ar-=0.5 (capacity ratio) and G as source gas
e) (4/Ar = 0.1 (volume ratio) was used. The conditions during deposition were as shown in Table 1. The opening degree of each valve and other conditions were kept constant during deposition. keep it to
A heating resistor layer having the thickness shown in Table 1 was formed.

After forming an At layer on the formed resistance layer by electron beam evaporation, the A1 layer is formed by photolithography.
The layer was etched into the desired shape to form multiple pairs of electrodes.

Subsequently, predetermined portions of the resistive layer were removed using an HF-based etching solution using Photoringraph and E technology. In this example, the size of the resistance layer between the electrode pairs is 200 pm x 3004 m. In this example, seven heating elements formed between the electrode pairs are arranged vertically. In this way, multiple heat generating resistor elements were fabricated on the same substrate.

The electrical resistance of each heating resistor element of the thus obtained thermal head was measured and found to be 85Ω.

Furthermore, an electrical pulse signal was input to each heating resistor element of the thermal head obtained in this example to measure the durability of the heating resistor element.

Note that the duty of the electrical pulse signal is 50%, and the applied voltage is 6.
v, drive frequency 0.5kHz, 1.0kHz, 2.0k
Hz.

As a result, in all cases of driving at different driving frequencies, the heating resistor element was not destroyed even when the electrical pulse signal input reached I x 1010 times, and its resistance value hardly changed.

Next, when we printed characters with a composition of 5 dots horizontally and 7 dots vertically using thermal recording paper, we found that the characters were 2×109
Even after the characters were printed, no problems such as missing dots occurred in the recorded characters. Furthermore, it was found that when the thermal head of this example was used as a so-called thermal transfer type in which recording is performed on recording paper via a thermal transfer ink ribbon, it also had extremely excellent durability.

Further, when recording was performed using so-called type paper with a rough surface as the recording paper, the thermal head of this example had extremely superior durability performance compared to the conventional thermal head. That is, compared to printing using the conventional thermal head, in which printing defects occurred after 30 million characters, in printing using the thermal head of this embodiment, no printing defects occurred after printing 30 million characters. There wasn't.

Example 2: A heating resistor layer with the same thickness was formed in the same manner as in Example 1 except that the raw material gases were C2FB/Ar=0,5 (capacity ratio) and GeH4/Ar=0.1 (capacity ratio). Deposited.

Next, when a thermal head was prepared in the same manner as in Example 1 and electrical pulse signals were input, the heating resistor element was not destroyed even when the electrical pulse signal input reached 1×10 10 times. Further, no change in resistance value was observed.

Next, in the same manner as in Example 1, printing was performed on thermal recording paper, further printing was performed as a thermal transfer type, and further printing was performed on type paper, and as in Example 1, sufficient durability was obtained. It was confirmed that

[Effects of the Invention] According to the present invention as described above, an amorphous material having carbon atoms as a matrix and containing germanium atoms, halogen atoms, and hydrogen atoms is used as the heating resistance layer.

As a result, a thermal recording head having extremely good responsiveness, thermal conductivity, heat resistance and/or durability, and further flexibility can be provided. In particular, the present invention provides a thermal recording head having an excellent heat generating resistance layer with good wear resistance and/or a low coefficient of friction.

[Brief explanation of drawings]

FIG. 1 is a partial plan view of the thermal recording head of the present invention;
rI! I is a cross-sectional view taken along the line ■-■. 3 and 4 are partial cross-sectional views of the thermal recording head of the present invention. FIG. 5 is a diagram showing an apparatus used for manufacturing the thermal recording head of the present invention. 2: Substrate 4: Heating resistance layer 6.7: Electrode 1101: Deposition chamber 1137, Substrate Agent Patent attorney Seki Yamashita Child 1 Figure 2 Figure 4 Figure 3

Claims (7)

[Claims] (1) In a thermal recording head in which at least one set of a heating resistance layer and at least one pair of electrodes electrically connected to the heating resistance layer is formed on a substrate, the heating resistance layer has carbon atoms as a matrix. A thermal recording head comprising an amorphous material containing germanium atoms, halogen atoms, and hydrogen atoms. (2) Claim 1, wherein the content of germanium atoms in the heating resistance layer is 0.0001 to 40 at%.
Thermal recording head. (3) The content of halogen atoms in the heating resistance layer is 0.
The thermal recording head of claim 1, wherein the thermal recording head has a content of 0,001 to 30 at. (4) Hydrogen atom content in the heating resistance layer is 0.00
The thermal recording head of claim 1, wherein the thermal recording head has a content of 0.01 to 30 atom %. (5) The sum of the germanium atom content, halogen atom content, and hydrogen atom content in the heating resistance layer is 0.
The thermal recording head of claim 1, wherein the thermal recording head has a content of 0,001 to 40 atom %. (6) The thermal recording head according to claim 1, wherein the halogen atom is F or Cl. (7) The thermal recording head according to claim 1, wherein the substrate has a surface layer made of an amorphous material containing carbon atoms as a matrix on the side on which the heat generating resistive layer is formed.