JPS61219105A - 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. And 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 responsiveness, so they are preferred as components of thermal recording heads, and their applications are 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 heating resistance layer is made of an amorphous material containing carbon atoms as a matrix, halogen atoms, hydrogen atoms, and a substance controlling electrical conductivity.

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 cross-sectional view taken along line II-II of the same.

In the figure, 2 is a support (substrate here), 4 is a heating resistance layer, and 6.7 is a pair of electrodes. tJ
As shown in Figure S1, the heating resistance layer 4 and the heating resistance layer 4
A plurality of sets with a pair of electrodes 6.7 connected to the
'', . is moved relative to the thermal paper or thermal transfer ink ribbon in the -■ direction, and at this time, the heat generating resistive layer 4 constituting the heat generating portions 8.8', 8'', Electric signals representing recording information are applied at appropriate times through the electrodes 6.7, and each heat generating section generates heat based on this, and the thermal energy at this time is used to perform recording by a thermal method or a thermal transfer method.

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, one heating resistance layer 4 is made of an amorphous material having carbon atoms as its base material and containing halogen atoms, hydrogen atoms, and a substance controlling electrical conductivity. As the halogen atom, F, C1, Br, ■, etc. can be used, and these may be used alone or in a combination of two or more. As the halogen atom, F and Cl are particularly preferable, and among them, F is preferable. As the substance that controls this, so-called impurities in the semiconductor field, that is, P-type impurities that provide P-type conductivity characteristics and n-type impurities that provide N-type conductivity characteristics can be used. Examples of p-type impurities include atoms belonging to Group Ⅰ of the periodic table of elements, such as B, AI, Ga, In, and TI, with B and Ga being particularly preferred @nJ! I! Impurities include atoms belonging to Group V of the periodic table of elements, such as P,
There are As, Sb, Bi, etc., and P and As are particularly preferred.
These may be used alone or in combination.

The content of halogen atoms in the heat generating resistor layer 4 is appropriately selected so as to obtain desired characteristics.

Preferably it is 0.0001 to 30 M%, more preferably 0.0005 to 20 at%, preferably o,
oot~l0JI child%.

The content of hydrogen atoms in the heat generating resistance layer 4 is as follows.

It is appropriately selected so as to obtain the desired characteristics, but preferably 0.0001 to 30! IX %, more preferably 0.0005 to 20 atomic %, preferably 0.00 atomic %
It is 1 to 10 at%.

The sum of the halogen atom content and the hydrogen atom content in the heat generating resistance layer 4 is appropriately selected so as to obtain desired characteristics, and is preferably 0.0001 to 40 atomic %, more preferably 0.0001 to 40 atomic %. is 0.0005 to 30 at%,
The content is preferably 0.001 to 20 atom %.

Further, the content of the electrically conductive substance in the Ja,1@ thin film 4 is appropriately selected so as to obtain desired characteristics, but is preferably o,, o i to 50,000 atomic pp.
m, more preferably 0.5 to 10,000 atomic pp
m, and optimally 1 to 50,001 ppm.

In the thermal recording head of the present invention, an amorphous material (hereinafter referred to as ra-C: (X)) comprising carbon as a matrix and containing halogen atoms, hydrogen atoms, and an electrically conductive controlling substance.

H) (p, n) Sometimes abbreviated as J. Here, X represents a halogen atom, and p and n represent electrically conductive substances. It is formed.

For example, a-C:(X) by glow discharge method.

)()(p,n) To form the resistive layer 4 consisting of ()()(p, n), basically the substrate 2 is placed in a deposition chamber under reduced pressure.

A raw material gas for C supply that can supply carbon atoms (C) into the deposition chamber, a raw material gas for X supply that can supply halogen atoms (X), and a raw material for H supply that can supply hydrogen atoms (H). A gas and a raw material gas for supplying an electrically conductive substance are introduced, and a glow discharge is generated in the deposition chamber using high frequency or microwave to cause &C: (X,
A layer consisting of H) (p, n) may be formed.

In addition, a-C2 (X.

In order to form the resistance layer 4 made of H) (p, n), basically the substrate 2 is placed in a deposition chamber under reduced pressure, and an inert gas such as Ar, He, etc. or an inert gas such as Ar, He, etc. When sputtering a target composed of C in an atmosphere of a mixed gas based on gases of All you have to do is introduce.

In the above method, the raw material gas for C supply, the raw material gas for X supply, the raw material gas for H supply, and the raw material gas for supplying electrically conductive substance may be in a gas state at room temperature and normal pressure, or in a reduced pressure. Any substance that can be gasified can be used.

Examples of raw materials for C supply include saturated hydrocarbons having 1 to 5 carbon atoms, ethylene hydrocarbons having 2 to 5 carbon atoms, acetylenic hydrocarbons having 2 to 4 carbon atoms, aromatic hydrocarbons, etc. The saturated hydrocarbons include methane (CH4), ethane (C2He), propylene (C3Hs), n-butane (n-C41(10), pentane (C5B12),
Ethylene (C2H4
), propylene (C3He), butene-1 (C4
H8), butene-2 (C4H8), inbutylene (
C4Ha), pentene (C5HIG), acetylene hydrocarbons such as acetylene (C282), methylacetylene (C384), butyne (C4Ha),
Examples of aromatic hydrocarbons include benzene (C6Ha) and the like.

Examples of raw materials for supplying X include halogens, halides, interhalogen compounds, halogen-substituted hydrocarbon derivatives, etc. Specifically, the halogens include F2, C12, and Br.
2, I2, halides include HF, HCl,
HBr, HI, interhalogen compounds include BrF, Cl
F, ClF3, BrF5, BrF3, IF3,
IF7, IC1, IBr, CF4, CHF3, CH2F2, C) as halogen-substituted hydrocarbon derivatives
(3F, CCl4.CHCl3.CH2Cl2.CH2
O1, CB r4 , CHB r3 , CH2B r2
, CH3Br, Cl4, CHI3, CH2I2, C
Examples include H3I.

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.

Examples of raw materials for supplying electrically conductive substances include the following.

Examples of raw materials for supplying group (III) atoms include B2 He, 84 HIO, B5 Hs, and B5 for supplying boron atoms.
1(tt, 861(to), boron hydride such as B6H12, B6H14, boron halide such as BF3, BC13, BBr3, etc. are used, and furthermore, for supplying other atoms, AlCl3, GaCl3, Ga(CH3)3.
InCl3. TlCl3 etc. are used.

As raw materials for supplying Group V atoms, for example, hydrogenated phosphorus such as PH3, F2 H4, PH41, P
F3, PFs, PC13.

PCl5. PBr3. PBr3. Phosphorous halides such as PI3 are used, and AsH3 is used to supply other atoms.
, AsF3, AsC13, AsBr3, AsF5
, SbH3, SbF3.5bFs, 5bC13, 5bC
1s, BiH3, BiCl3. B1Br3 etc. are used.

These raw materials may be used alone or in combination.

In the heat generating resistive layer forming method as described above, in order to control the amount of halogen atoms, the amount of hydrogen atoms, the amount of electrical conductivity controlling substance and the characteristics of the resistive layer 4 contained in the resistive layer 4 to be formed, The substrate temperature, supply amount of raw material gas, discharge power, pressure in the deposition chamber, etc. are appropriately set.

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

The discharge power is preferably o-oot~20W/crn',
More preferably 0-01 to 15 W/c, optimally 0.
05 to IOW/crn”.

The pressure within the deposition chamber is preferably 10-4. ~10 Tor
r, 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, a Vickers hardness of 1800 to 5000.
Thermal conductivity 0.3-2 cal/cm e sec
*"0, resistivity 105~1011Ωfist cm, thermal expansion coefficient 2X10-5~10-8/"O1 friction coefficient 0.15
~0.25 and a density of 1.5 to 3.0, and contains halogen atoms, hydrogen atoms, and electrical conductivity controlling substances, so resistance value controllability is extremely good.

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, the substrate in the present invention may be a composite. The structure of such an embodiment is shown in FIG. 4, in which the substrate 2 is composed of a support 2a and a surface layer 2b The support material 2a can be made of the support material described in connection with FIG. The surface layer 2'b, in which a material with better properties can be used, is made of, for example, an amorphous material having carbon atoms as a host, a conventionally known oxide, or the like. Such a surface layer 2b can be obtained by depositing appropriate raw materials on the support za by a method similar to the above-mentioned method for forming the heating resistor layer. Further, the surface layer 2b 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, the outline of the method for manufacturing the thermal recording head of 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, 1102 to 1106 are gas cylinders, and 1107
~1111 is a mass flow controller, 1112
-1116 are inflow valves, 1117-1121 are outflow valves, 1122-112B are gas cylinder valves, 1127-1131 are outlet pressure gauges, 1132 is an auxiliary valve, 1133 is a lever, 1134 is a main valve, 1135 is a leak valve, 1136 is a vacuum gauge, 1137 is the base material of the thermal head to be manufactured, 1138
1139 is a heater, 1139 is a base support means, and 11
40 is a high voltage power supply, t 141 is an electrode, 1
142 is a shutter. Note that 1142-1 is a target attached to the electrode 1141 when performing the sputtering method.

For example, 1102 is sealed with CF4 gas (99.9% purity or higher) diluted with Ar gas, and 1103
PH3 gas diluted with Ar gas (99.9% purity)
1104 is sealed with 82 H gas (purity of 99.9% or more) diluted with Ar gas. Before the gas in these cylinders is allowed to flow into the deposition chamber 1101, it is confirmed that the valves 1122 to 1126 and the leak valve 1135 of each gas cylinder 1102 to 110B are closed, and that the inflow valve 1112 is closed.
~111B, confirm that the outflow valves 1117 to 1121 and the auxiliary valve 1132 are open, and first open the main valve 1134 to evacuate the deposition chamber and gas piping. Next, check the reading on the vacuum gauge 1136. Approximately 1.5
When the temperature reaches XIO-6 Torr, the auxiliary valve 113
2. Inflow valves 1112 to 1116 and outflow valve 11
Close 17-1121. 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 a procedure for forming the resistive layer of the thermal recording head of the present invention by a glow discharge method using one or more devices will be described. Open the valve 1122 and open the gas cylinder 11.
Let the CF4/Ar gas flow out from the valve 1123.
Open it to let PH37Ar gas flow out from the gas pump 1103, and check the pressure on the outlet pressure gauges 1127 and 1128.
g/crn', then inlet valve 1112.1l
13 gradually opens the mass flow controller 1107.
1108 and then the outflow valve 11
17.1118, gradually open the auxiliary valve 1132 and
F4/At gas and P H3/Ar gas are deposited in deposition chamber 1.
101. At this time, adjust the mass flow controllers 1107 and 1118 so that the ratio of the flow rate of CF4/Ar gas and the flow rate of PH3/Ar gas becomes a desired value,
Also, while checking the reading on the vacuum gauge 1136, make sure that the pressure inside the deposition chamber 1tot reaches the desired value.
) Adjust the opening. Then, the temperature of the base 1137 supported by the support 1139 in the deposition chamber 1101 is heated by the heater 1138 to a desired temperature, and then the shutter 1142 is opened to generate a glow discharge in the deposition chamber 1101. .

Next, an example of a procedure for forming the resistive layer of the thermal recording head of the present invention by sputtering using one or more devices 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 is preliminarily applied.
1142-1 as a target, C from gas pump 1102 in the same way as in the glow discharge method.
Transfer F4/Ar gas from gas pump 1103 to PH3/Ar
Each gas is introduced into the deposition chamber 1101 at a desired flow rate. The shutter 1142 is opened and the high voltage power supply 1140
The target 1142-1 is sputtered by supplying the target 1142-1. 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 1tot to a desired pressure is similar to the glow discharge method.

In the case of a thermal recording head such as that shown in FIGS. 1 and 2, the formation of the heat generating resistive layer on the substrate by one or more of the glow discharge method and sputtering method 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 a conductive layer is previously formed on a substrate and the conductive layer is etched using photolithography, a heat generating resistive layer is formed on the substrate by one or more of the glow discharge methods and sputtering methods.

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

Example 1: A substrate consisting of a support made of an alumina ceramic plate and a glaze layer provided thereon was used as the substrate, and a heating resistor layer was formed on the surface of the substrate.The deposition of six heating resistor layers 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 (volume ratio) and PH as raw material gas
3/Ar=1000 ppm (capacity ratio) was used. The conditions during the deposition were as shown in Table 1. During the deposition, the opening degree of each valve and other conditions were kept constant, and a heat generating resistor layer having the thickness shown in Table 1 was formed.

After forming an A1 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 by photolithography using an HF-based etching solution. still,
In this example, the size of the resistance layer between the electrode pairs is 200 ILm x 300 JLm. A plurality of heating resistance elements were fabricated on the top.

The electrical resistance of each heating resistor element of the thus obtained thermal head was measured and found to be 80Ω.

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 1×10 10 times, and its resistance value hardly changed.

Next, when we printed characters with a composition of 5 horizontal dots x 7 vertical dots using thermal recording paper, the result was 2 x 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.

Furthermore, when recording was performed using so-called type paper with a rough surface as recording paper, the thermal head of this example had extremely superior durability performance compared to conventional thermal heads. 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: Raw material gas was CF4/Ar=0.5 (capacity ratio) and 8
2 A heating resistor layer having the same thickness was deposited in the same manner as in Example 1 except that H6/Ar=1000 ppm (capacitance ratio).

Next, when a thermal conductor was prepared in the same manner as in Example 1 and an electrical pulse signal was input, the heating resistor element was not destroyed even when the electrical pulse signal input reached 1XloIO 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 a carbon atom as a matrix and containing a halogen atom, a hydrogen atom, and an electrically conductive dominant substance is used as one heating resistance layer. Accordingly, a thermal recording head having extremely good thermal responsiveness, thermal conductivity, heat resistance and/or durability, and further excellent controllability of resistance value can be provided. In particular, one aspect of 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 the drawing]

FIG. 1 is a partial plan view of the thermal recording head of the present invention;
The figure is a sectional view taken along 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. 22 Substrate 4: Heating resistance layer 6.7: Electrode 1101: Deposition chamber 1137: Substrate Agent Patent attorney Seki Yamashita Figure 2 Figure 3 Figure 4N

Claims (9)

[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 characterized in that it is made of an amorphous material containing halogen atoms, hydrogen atoms, and a substance that controls electrical conductivity. (2) 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. (3) 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 %. (4) The thermal recording head according to claim 1, wherein the sum of the halogen atom content and the hydrogen atom content in the heat generating resistive layer is 0.0001 to 40 at %. (5) The thermal recording head according to claim 1, wherein the halogen atom is F or Cl. (6) The thermal recording head according to claim 1, wherein the content of the substance controlling electrical conductivity in the heating resistance layer is 0.01 to 50,000 atomic ppm. (7) The substance that controls electrical conductivity is the element III of the periodic table.
The thermal recording head according to claim 1, which is an atom belonging to the group (8) The thermal recording head according to claim 1, wherein the substance controlling electrical conductivity is an atom belonging to Group V of the Periodic Table of Elements. (9) 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 heating resistance layer is formed.