JPH0531903A - Substrate for ink jet head, ink jet head using same and ink jet device equipped with the ink jet head - Google Patents

Abstract

PURPOSE:To improve endurance, safety, resistance against cavitation and thermal condictivity by constituting a thermal resistor with a non-crystal material containing two elements such as Ir and Al composed at a specific ratio. CONSTITUTION:A non-single crystal Ir-Al material containing essential components, Ir and Al composed at a ratio of 54 atomic% <=Ir<=95 atomic% and 5 atomic% hAl<=46 atomic% provides the best suitability of a thermal resistor to an ink jet head. The thermal resistor of this material demonstrate a high thermal conductivity to ink as a thermal energy generated is allowed to act on the ink directly. An electricity/heat conversion element having a thermal resistor layer 103 and electrodes 104, 105 is formed on a support consisting of a lower layer 103 which is formed on the surface of a substrate 101. Thus the electricity/-heat conversion element is part of the ink jet head. In addition, a protecting layer 106 which covers at least, electrodes 104, 105 of the electricity/heat conversion element is laminated and further, a grooved plate 107 where a recessed part for providing a flow path communicating with a discharge orifice 108 is formed, is junctioned to the surface of the protecting layer 106.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to resistance to cavitation impact, resistance to cavitation erosion, chemical stability, electrochemical stability, oxidation resistance, dissolution resistance, heat resistance, heat shock resistance, and mechanical properties. TECHNICAL FIELD The present invention relates to an inkjet head and an inkjet device which are provided with an electrothermal converter excellent in durability and the like. The ink jet head and the ink jet device include an electrothermal converter having a heat generating resistor that generates heat energy by energizing the heat energy for directly applying heat energy to the ink on the heat acting surface to eject the ink. The thing can be mentioned as a typical example. The electrothermal converter has low power consumption and excellent responsiveness to an input signal.

[0002]

2. Description of the Related Art The ink jet method described in Japanese Patent Publication No. 61-059911 and Japanese Patent Publication No. 61-059914 is capable of high-speed, high-density, high-definition and high-quality recording, colorization, and compactness. It has been attracting attention in recent years. In a typical example of an apparatus using this method, since the ink that is a recording liquid is ejected by using thermal energy, there is a heat acting portion that applies heat to the ink. That is, a heating resistor having a heat acting portion is provided corresponding to the ink path, the heat energy generated from the heating resistor is used to rapidly heat and foam the ink, and the foaming ejects the ink. Is.

From the viewpoint of applying heat to an object, the heat acting portion has a portion that is similar to the structure of a conventional so-called thermal ink jet head, but the heat acting portion is in direct contact with the ink. , The heat acting part is exposed to mechanical impact or erosion in some cases due to cavitation caused by repeated foaming and defoaming of ink, and the heat acting is extremely short time of the order of 10 ^-1 to 10 ^-6 seconds. The basic technology is greatly different from that of the thermal inkjet head in that it is exposed to temperature rises and falls of nearly 1000 ° C. Therefore, it goes without saying that the thermal inkjet head technology cannot be directly applied to the bubble jet technology. That is, the thermal inkjet head technology and the inkjet technology cannot be discussed in the same row.

By the way, the heat acting portion of the ink jet head is exposed to the harsh environment as described above.
_It is general to provide an electrically insulating layer made of ₂ , SiC, Si ₃ N ₄ or the like, and a cavitation resistant layer made of Ta or the like on the electrically insulating layer to protect the heat acting part from the use environment. As a constituent material of the protective film used in such an ink jet head, for example, Japanese Patent Publication No. 59-4
Materials that are strong against impact and erosion due to cavitation described in Japanese Patent No. 3315 can be mentioned. Incidentally, wear-resistant layer made of Ta ₂ 0 _5, etc. commonly used in thermal ink jet head is not necessarily excellent in cavitation resistance.

Separately from this, in order to reduce power consumption and enhance responsiveness to an input signal, the heat generated by the heating resistor is used as efficiently and promptly as possible for the heat acting portion of the ink jet head. Is desired to act on. Therefore, in JP-A-55-126462, there has been proposed a form in which the heating resistor is in direct contact with the ink, in addition to the form in which the protective film is provided.

Although the ink jet head of this form is superior to the form in which the protective film is provided in terms of thermal efficiency, not only is the heating resistor exposed to impact and erosion due to cavitation, and also to rise and fall of temperature. Since the recording liquid in contact with the heating resistor has conductivity, an electric current also flows in the recording liquid, and the heating resistor is exposed to the electrochemical reaction that occurs as a result. For this reason, various metals, alloys, metal compounds, or cermets such as Ta ₂ N and RuO ₂ which are conventionally known as materials for heat generating resistors can be used as heat generating resistors for ink jet heads of this form. Durability and stability are not always sufficient.

As the ink jet head having the above-mentioned protective film, it has been proposed that the inkjet head can be practically used in terms of durability and resistance change. In any case, the protective film is formed. It is extremely difficult to completely prevent the occurrence of defects that occur from time to time, and this is a major factor in reducing the yield during mass production. This is becoming a big problem because there is a demand for higher speed recording and higher density recording, and the number of ejection ports of the inkjet head tends to increase correspondingly.

Further, the above-mentioned protective film lowers the heat transfer efficiency from the heating resistor to the recording liquid, but if this heat transfer efficiency is poor, the overall power consumption required increases and the ink jet head of the ink jet head during driving is increased. The temperature change becomes large. This temperature change leads to a change in the volume of the droplet ejected from the ejection port, which causes a density change in the image. In addition, when the number of ejections per hour is increased in order to correspond to the speeding up of recording, the power consumption of the inkjet head increases accordingly, and the temperature change increases, and the temperature change corresponds to the obtained image. This will cause a change in concentration. Further, even when the discharge ports are multi-sized with the increase in the density of the electrothermal converter, the power consumption in the inkjet head rises, and the temperature change due to this also changes the density of the obtained image according to the temperature change. Will be accompanied by. The problem that the obtained image has a change in density is contrary to the demand for high quality of the recorded image, and is a problem that requires an early solution.

In order to solve such a problem, it has been earnestly desired to provide an ink jet head which is in direct contact with a heating resistor and ink and has high thermal efficiency.

[0010]

However, as described above, in the conventional form in which the ink directly contacts the heat-generating resistor, the heat-generating resistor is exposed to the impact of cavitation, erosion, and temperature rise and fall. Not only is it exposed to electrochemical reactions,
Conventional heating material such as Ta ₂ N, RuO ₂ and HfB ₂ has a problem in durability such as mechanical destruction, corrosion and dissolution.

The material described in Japanese Patent Publication No. 59-43315, which is resistant to impact and erosion due to cavitation, exhibits its effect only when used as the protective film (anti-cavitation layer) as described above. Is. However, when this material is used as a heating resistor that is in direct contact with ink, it may be dissolved or corroded by an electrochemical reaction, and sufficient durability cannot be obtained.

In addition, ejection stability is indispensable for high-definition and high-quality recording, and for that purpose, it is necessary that the resistance change of the heating resistor is small, which is practically 5%.
The following is desirable. The Ta or Ta-Al alloy described in JP-A-59-96971 is durable in that the resistor does not break when it is used as a heat-generating resistor that is in direct contact with the ink of an inkjet head, that is, resistance. It is relatively excellent in cavitation.
However, in terms of resistance change during repeated foaming, for example, Ta and Ta-Al alloys are not so small and not satisfactory. Furthermore, Ta and Ta-
With Al alloy, the applied pulse voltage (Vbr
Eak) and foaming threshold voltage (Vth) ratio M is not so high and heat resistance is not so high, driving voltage (Vop)
There is a problem that the life of the resistor may be greatly reduced by a slight increase in That is, Ta or Ta-
The Al alloy does not always have sufficient resistance to an electrochemical reaction. Therefore, when it is used as a material for a heating resistor that is in direct contact with the ink of an ink jet head, when foaming is repeated by a large number of applied pulses, the heating resistor is Electrical resistance changes greatly, which also changes the state of foaming, and because the heat resistance is not so great, a slight change in Vop may greatly affect the life of the resistor. There is.

As described above, even if the heating resistor which is directly in contact with the recording liquid (that is, ink) is formed of the conventionally known material, the resistance to the impact of cavitation, the resistance to the erosion due to the cavitation, the mechanical durability, It is difficult to obtain an ink jet head or an ink jet device which can satisfy all of chemical stability, electrochemical stability, resistance stability, heat resistance, oxidation resistance, dissolution resistance and thermal shock resistance.

In particular, an ink jet head having a structure in which a heating resistor is provided so as to be in direct contact with ink, has high heat conduction efficiency, is excellent in signal responsiveness, and has sufficient durability and ejection stability. And it is difficult to obtain an inkjet device. A main object of the present invention is to provide an improved ink jet head and an ink jet device having the ink jet head, which solves the above-mentioned problems in the conventional ink jet head in which ink directly contacts the heating resistor. .

Other objects of the present invention are resistance to impact of cavitation, resistance to erosion due to cavitation, mechanical durability, chemical stability, electrochemical stability, resistance stability, heat resistance, oxidation resistance, It is an object of the present invention to provide an improved inkjet head having excellent dissolution resistance and thermal shock resistance and excellent thermal conductivity.

A further object of the present invention is to have a structure in which the heating resistor is in direct contact with the recording liquid (that is, ink), so that it is always on stably even when it is repeatedly used for a long time. An object of the present invention is to provide an improved inkjet head that responds to a demand (on demand) signal immediately and efficiently transfers heat energy to the recording liquid to eject ink to provide an excellent recorded image.

Still another object of the present invention is to have a structure in which a heating resistor is in direct contact with a recording liquid, the power consumption by the heating resistor is kept low, and the temperature change of the ink jet head is extremely reduced. An object of the present invention is to provide an improved inkjet head that is small in size and that constantly ejects ink even when it is repeatedly used for a long time so that an image obtained does not change in density due to a change in temperature of the inkjet head. Another object of the present invention is to provide an inkjet device having the inkjet head described above.

[0018]

The ink jet head substrate of the present invention is a heat generating resistor which is generated by energizing the thermal energy used to directly apply thermal energy to the ink on the heat acting surface to eject the ink. In the inkjet head substrate having an electrothermal converter having a body, the heating resistor is made of a material containing at least Ir and Al in the following composition ratios.

54 at.%. Ltoreq.Ir.ltoreq.95 at.% 5 at.%. Ltoreq.Al.ltoreq.46 at.% Further, the ink jet head and the ink jet apparatus of the present invention are constructed by using the above ink jet head substrate.

[0020]

The present inventors have conducted extensive studies to solve the above-mentioned problems in the conventional ink jet head in which ink directly contacts the heat generating resistor and achieve the above object. By forming the resistor with a non-single crystalline substance containing two elements of iridium (Ir) and aluminum (Al) in a specific composition ratio, it was found that an inkjet head that achieves the above object can be obtained. The present invention has been completed based on the above.

The non-single crystalline material is iridium (I
r) and aluminum (Al) with 54 elements each
It is a polycrystalline material containing at a composition ratio of from 95 to 95 atom% and from 5 to 46 atom%.

The present inventors have selected iridium (Ir) from the viewpoint of a substance that is rich in heat resistance and oxidation resistance and chemically stable, has mechanical strength, and is excellent in solvent solubility. Aluminum (A
1) was selected, and a plurality of non-single crystalline material samples containing these two elements with a predetermined composition were prepared by the sputtering method.

Each of the samples has a sputtering device (trade name: sputtering device CFS-8) shown in FIG.
EP, manufactured by Tokuda Manufacturing Co., Ltd.) was used to form a film on a single crystal Si substrate and a Si single crystal substrate having a thermally oxidized SiO ₂ film of 2.5 μm formed on the surface.

In the film forming chamber 601, a substrate holder for holding a substrate 603 on which a film forming process is performed is provided. The substrate holder 602 has a built-in heater (not shown) for heating the substrate 603. Board holder 60
Reference numeral 2 is supported by a rotary shaft 608 extending from a drive motor (not shown) installed outside the system, and is designed to be vertically movable and rotatable. A target holder 605 for holding a film formation target is installed at a position facing the substrate 603 in the film formation chamber 601. The Al target 606 placed on the surface of the target holder 605 is made of A having a purity of 99.9% by weight or more.
The two Ir targets 607 disposed on the Al target 606 are 99.9% by weight.
The Ir sheet has the above-mentioned purity. As illustrated, two Ir targets 607 each having a predetermined area are arranged at a predetermined interval according to the surface area of the Al target 606. The individual areas and arrangements of the Ir targets 607 were determined beforehand to find out how to obtain a film containing desired Ir and Al in a predetermined composition ratio so as to obtain the relationship of the area ratios of the two types of targets, and prepare a calibration curve. Then, it is performed based on the calibration curve.

When the composition ratio is constant and more stable film formation is performed, a concave portion having the shape of the Ir target 607 is formed in the Al target 606 by cutting, and the Ir target 607 is electrically welded to the concave portion. You may fix it with the etc.
In this way, the position of the Ir target 607 does not shift, and it is possible to form a film with good reproducibility even by sputtering a plurality of times. Al target 606 at this time
The cutting process is also easy.

The protective wall 618 covering the side surface of the target holder 605 includes an Al target 606 and an Ir target 6.
07 are provided so as to cover the periphery thereof so as not to be sputtered by the plasma from the side surface.

The RF power source 615 is the matching box 6
It is electrically connected to the peripheral wall of the film forming chamber 601 through the 14 and the conducting wire 616, and is electrically connected to the target holder 605 through the matching box 614 and the conducting wire 617.

The target holder 605 is provided with A during film formation.
A mechanism (not shown) for internally circulating cooling water is provided so that the 1 target 606 and the Ir target 607 are maintained at a predetermined temperature. The film forming chamber 601 is provided with an exhaust pipe 610 for exhausting the inside of the film forming chamber 601, and the exhaust pipe 610 communicates with a vacuum pump (not shown) via an exhaust valve 611. There is. The gas supply pipe 612 is for introducing a sputtering gas such as an argon gas (Ar gas) or a neon gas (Ne gas) into the film forming chamber 601, and the flow rate of these sputtering gases is set to the gas supply pipe 612. It is controlled by a flow rate control valve 613 provided in the. The insulator 609 is provided between the target holder 605 and the bottom wall of the film forming chamber 601 in order to electrically insulate the target holder 605 from the film forming chamber 601. The vacuum gauge 619 is a film forming chamber 601.
It is provided to detect the internal pressure of the vacuum chamber, and the sputtering conditions are set using the pressure detected by the vacuum gauge 619.

The shutter plate 604 is located above the target holder 605 and is located on the substrate 603 and the Al target 60.
6 and the Ir target 607 are provided so as to move horizontally so as to block the space between them. The shutter plate 604 is used as follows. Before starting film formation,
The Al target 606 and the Ir target 607 are moved to the upper part of the target holder 605, and an inert gas such as argon (Ar) gas is introduced into the film forming chamber 601 through the gas supply pipe 612. RF power is applied to turn the inert gas into plasma, and the generated plasma causes Al target 606 and Ir target 6
07 is sputtered to remove impurities on the surface of each target. After that, the shutter plate 604 is moved to a position (not shown) that does not damage the film formation.

The apparatus shown in FIG. 6 has a form in which one target holder is provided as described above, but it is also possible to provide a plurality of targets. In that case, those target holders are arranged on the concentric circles at equal intervals at positions facing the substrate 603 in the film forming chamber 601. And
Each target holder has an independent RF
Connect the power supply electrically through the matching box. In such a case, since two types of targets are used, that is, an Ir target and an Al target,
The individual target holders are arranged in the film forming chamber 601 as described above, and the respective targets are individually set on the respective target holders. In this case, given RF power can be applied independently to each target,
It is possible to form a film in which one or more elements of Ir and Al are changed in the film thickness direction by changing the composition ratio of the film constituent elements to be formed.

The preparation of each sample using the apparatus shown in FIG. 6 described above is carried out each time on the Al target 606.
The film forming conditions were as follows, except that the r target 607 was arranged based on a calibration curve prepared in advance for a non-single crystalline material (film) having a predetermined Ir and Al composition ratio.

Substrate placed on substrate holder 602: 4 in
chφ size Si single crystal substrate (manufactured by Wacker) (1 sheet)
And 4inc with 2.5 μm thick SiO ₂ film formed on the surface
hφ size Si single crystal substrate (manufactured by Wacker) Substrate setting temperature: 50 ° C. Base pressure: 2.6 × 10 ⁻⁴ Pa or less High frequency (PF) power: 1000 W Sputtering gas and gas pressure: Argon gas,
0.4 Pa film formation time: SiO _{2 of} each sample obtained as above for 12 minutes
Some samples of the film formed on the film substrate were subjected to electron emission using EPM-810 manufactured by Shimadzu Corporation.
Probe microanalysis was performed to analyze the composition, and then the sample formed on the Si single crystal substrate
Crystallinity was observed by an X-ray diffractometer (trade name: MXP3) manufactured by Science. The results obtained are summarized in Table 1. In Table 1, C indicates that the sample is a polycrystalline substance, M indicates that the sample is a polycrystalline substance and amorphous substance, and A indicates that the sample is an amorphous substance. Indicated by.

Next, a so-called pond test for observing the resistance to an electrochemical reaction and the resistance to a mechanical shock was carried out using another part of each sample formed on a SiO ₂ film substrate, and further SiO ₂ was used. A step stress test (SST) for observing heat resistance and impact resistance in air was performed using the residue formed on the _two- film substrate. In the pond test, as a dipping liquid, a liquid obtained by dissolving 0.15 wt% of sodium acetate in a solution of 70 parts by weight of water and 30 parts by weight of diethylene glycol was used. The same method as the "foaming endurance test". When the results of the pond test and the results of the SST were comprehensively examined, a preferable sample was a polycrystalline substance, and the composition ratios of Ir and Al were 54 to 95 atomic% Ir and 5 to 95 atomic% Al. It was found to be 46 atom%. From the above results, the present inventors have found that a non-single crystal Ir-Al substance containing Ir and Al as essential components in the following composition ratios is suitable for use as a heating resistor of an inkjet head.

54 at.%. Ltoreq.Ir.ltoreq.95 at.% 5 at.%. Ltoreq.Al.ltoreq.46 at.% Further, the present inventors constructed a heating resistor using this non-single-crystal Ir-Al substance to manufacture an ink jet head. After that, the facts described below were found.

That is, when the non-single-crystal Ir-Al substance is used, it has a heating resistor which is excellent in resistance to cavitation impact, resistance to cavitation erosion, electrochemical and chemical stability and heat resistance. An inkjet head can be obtained. In particular, it is possible to obtain an inkjet head having a structure in which the heat generating portion of the heating resistor is in direct contact with the ink in the ink path. In the ink jet head having this structure, the heat energy generated from the heat generating portion of the heat generating resistor can be directly applied to the ink, so that the heat conduction efficiency to the ink is good. Therefore, the power consumption by the heating resistor can be suppressed to a low level, and the temperature rise of the inkjet head (the temperature change of the inkjet head) can be significantly reduced, so that the image density change due to the temperature change of the inkjet head is avoided. be able to. Further, it is possible to obtain a better responsiveness to the ejection signal applied to the heating resistor.

Further, in the heat generating resistor according to the present invention, it is possible to obtain a desired specific resistance value with good controllability and to make the dispersion of the resistance value within one ink jet head extremely small. Therefore, it is possible to eject the ink much more stably than before and to obtain an ink jet having excellent durability.

The ink jet head having good characteristics as described above is very suitable for high speed recording and high image quality due to the multi-ejection.

Therefore, according to one aspect of the present invention, the electric heat having the heating resistor for generating the thermal energy, which is used to directly apply the thermal energy to the ink on the heat acting surface to eject the ink, by the energization. In an inkjet head including a converter, the heating resistor is substantially composed of Ir and Al, and is composed of a non-single crystalline material containing Ir and Al in the following composition ratios. An inkjet head is provided.

24 atom% ≦ Ir ≦ 68 atom% 32 atom% ≦ Al ≦ 76 atom% In the present invention, when the heating resistor of the ink jet head is made of the above specific non-single-crystal Ir-Al substance,
The reason why the above-mentioned various remarkable effects are obtained is not yet clear, but as one of the reasons, heat resistance, oxidation resistance,
It is conceivable that Ir, which is excellent in chemical stability, prevents the reaction, and Al imparts mechanical strength and forms a stable oxide to bring about dissolution resistance.

As described above, the non-single crystalline substance containing Ir and Al in the above-mentioned specific composition ratios, because these two elements organically act on each other, It can be used as a heating resistor that can be in direct contact for a long period of time.

The present inventors have found that the above-mentioned specific non-single-crystal I
It has been confirmed through experiments that, when a heating resistor for an inkjet head is formed using a non-single-crystal Ir-Al substance other than the r-Al substance, there are problems as described below.

That is, the resistance to cavitation impact, the resistance to cavitation erosion, the electrochemical stability, the chemical stability, the heat resistance, the adhesion, the internal stress, etc. are not appropriate, and the heating resistor of the ink jet head, especially Sufficient durability cannot be obtained when it is used as a heating resistor of the type that comes into direct contact with ink.
For example, when the amount of Ir is too large, the film may be peeled off, and on the contrary, when the amount of Al is too large, the resistance change may be significant.

The thickness of the heating resistor layer in the present invention is
It is appropriately determined so that appropriate heat energy is effectively generated, but from the viewpoint of durability and production characteristics, it is preferably 3
00Å to 1 μm, more preferably 1000Å to 5000
It is Å.

Further, the heating resistor according to the present invention may have the surface layer portion, particularly the surface layer portion in contact with the ink having the above-mentioned composition, and the composition is not necessarily uniform over the entire heating resistor. There is no. For example, even if the heating resistor is composed of a plurality of layers, or even if the composition has a distribution in the layer thickness direction, as long as the above-described conditions are satisfied, the effect of the present invention can be obtained, and particularly It is possible to obtain more excellent adhesion to the support.

Further, in general, the surface or the inside of the layer may be exposed to the atmosphere, or may be oxidized or take in a gas during the manufacturing process. Slight oxidation and Ar on the surface and inside
Incorporation of the above does not reduce its effect. Examples of such impurities include at least one element selected from C, N, Si, B, Na, Cl and Fe, including Ar and O.

In addition, the heating resistor according to the present invention is formed by, for example, a DC sputtering method, an RF sputtering method, an ion beam sputtering method, a vacuum deposition method, a CVD method, or the like, in which the respective materials are deposited simultaneously or alternately. be able to.

[0047]

EXAMPLE Next, an example of an ink jet head according to the present invention, which is excellent in thermal efficiency, signal responsiveness and the like, using an alloy material having the above-mentioned composition as a heating resistor will be described with reference to the drawings.

FIG. 1A shows the first part of the ink jet head.
1B is a schematic front view of the embodiment of FIG.
FIG. 3 is a sectional view taken along line XY in FIG.

The ink jet head of this example has the substrate 1
On a support having a lower layer 102 provided on the surface of 01,
A heating resistor layer 103 having a predetermined shape and an electrode 104,
For forming an electrothermal conversion element having a protective layer 106 covering at least the electrodes 104 and 105 of the electrothermal conversion element, and further providing a liquid path 111 communicating with the ejection port 108 thereon. Grooved plate 1 having a recess
It has a basic structure in which 07 is joined.

The electrothermal converter in this example comprises a heating resistor layer 103 and an electrode 10 connected to the heating resistor layer 103.
4, 105 and a protective layer 106 provided as necessary. The inkjet head substrate has a support having a substrate 101 and a lower layer 102, an electrothermal converter, and a protective layer 106. In the case of the ink jet head of this example, the heat acting surface 109 that directly transfers heat to the ink is the electrode 10 of the heat generating resistor layer 103.
The part sandwiched between 4, 105 (heat generating part) is almost the same as the surface in contact with the ink, and the protective film 106 of the heat generating part.
It corresponds to the part not covered with.

The lower layer 102 is provided as needed,
It has a function of adjusting the amount of heat escaping to the substrate 101 side and efficiently transmitting the heat generated in the heat generating portion to the ink.

The electrodes 104 and 105 are electrodes for energizing the heating resistor layer 103 in order to generate heat from the heat generating portion. In this example, the electrode 104 is a common electrode for each heat generating portion, and the electrode 105 is each heat generating portion. It is a selection electrode for individually energizing the generator.

The protective layer 106 is provided as necessary in order to prevent the electrodes 104 and 105 from coming into contact with ink to be chemically attacked, or to prevent a short circuit between the electrodes through the ink.

FIG. 2A is a schematic plan view of the ink jet head substrate at the stage where the heat generating resistor layer 103 and the electrodes 104 and 105 are provided. Also, FIG.
(B) is a schematic plan view of the inkjet head substrate at the stage where the protective layer 106 is provided on these layers.

In this ink jet head, since the alloy material having the above composition is used for the heating resistor layer 103, the ink is good even though the ink and the heat acting surface 109 are in direct contact with each other. Has excellent durability.
In this way, if the heat generating portion of the heat generating resistor that is the heat energy source is in direct contact with the ink, the heat generated in the heat generating portion can be directly transferred to the ink, and the heat is generated via the protective layer. The heat transfer can be performed extremely efficiently as compared with the structure that transfers the heat to the ink.

As a result, the power consumption of the heating resistor can be kept low and the temperature rise of the ink jet head can be reduced. Further, the responsiveness to the input signal (discharge command signal) to the electrothermal converter is improved,
The foamed state required for ejection can be stably obtained.

The construction of the electrothermal converter having the heating resistor formed by using the alloy material according to the present invention is shown in FIG.
The present invention is not limited to the first embodiment shown in FIG. 2 and various modes can be adopted.

FIG. 3 is a schematic sectional view showing the structure of the main part of the second embodiment of the ink jet head.

In this embodiment, an electrothermal converter having a heating resistor layer 103 having a predetermined shape and electrodes 104 and 105 is formed on a support having a lower layer 302 provided on the surface of a substrate 301. It was done. In the ink jet head substrate of the present embodiment, the electrodes 304 and 305 are covered with the heating resistor layer 303 made of the alloy material having the above composition, and the electrode protective layer is omitted.

In the first embodiment shown in FIGS. 1A and 1B, the direction in which ink is supplied onto the heat acting surface 109 and the heat energy generated from the heat generating portion are Although the directions in which the ink is ejected from the ejection ports 108 are substantially the same, the configurations of the ejection ports and the liquid passages of the inkjet head are not limited to this, and these directions are different. May be.

FIG. 4 is a schematic sectional view showing the construction of the main part of the third embodiment of the ink jet head.

In this embodiment, as shown in the plan view of FIG. 4A and FIG. 4B which is a sectional view taken along the line AB of FIG. A configuration in which the two directions form a substantially right angle is also possible. In FIG. 4, the ejection port plate 410 is a plate having an appropriate thickness provided with ejection ports, and the support member 412 supports the ejection port plate 410. Since the other structure is the same as that of the first embodiment shown in FIGS. 1 and 2,
The same reference numerals as those in FIGS. 1 and 2 are given and the description thereof is omitted.

The ink jet head of the present invention may have a plurality of ink ejection structure units each having an ejection port, a liquid path and a heat generating portion, as shown in FIGS. For this reason, the present invention is particularly effective when the ink discharge units are arranged at a high density of, for example, 8 lines / mm or more, further 12 lines / mm or more. An example of the ink jet structure having a plurality of ink discharge structure units is a so-called full line type inkjet head having a structure in which the ink discharge structure units are arranged over the entire width of the print area of the recording member. In the case of a so-called full-line inkjet head in which a plurality of ejection openings are provided corresponding to the width of the recording area of the recording member, in other words, an inkjet head having 1000 or more ejection openings or 2000 or more ejection openings. In this case, the variation in the resistance value of each heat generating portion in one inkjet head may affect the uniformity of the volume of the droplets ejected from the ejection port, which may cause the uneven density of the image. is there. However, with the heating resistor according to the present invention, it is possible to obtain a desired specific resistance value with good controllability, and it is possible to obtain an extremely small variation in the resistance value within one ink jet head. It can be resolved in good condition.

As described above, the heating resistor according to the present invention is
High-speed recording (for example, 30 cm / sec or more, further 60 cm
(Printing speed of / sec or more) and higher density are required, and the number of ejection ports of the inkjet head is correspondingly increasing, which has an increasing significance.

Further, in the ink jet head in which the functional element is structurally provided inside the surface of the ink jet head substrate as disclosed in US Pat. No. 4,429,321, the ink jet head is used. It is one of the important points that the entire electric circuit is accurately formed as designed so that the function of the functional element can be easily maintained in a normal state, and the heating resistor according to the present invention also has this meaning. It is extremely effective. This is because, as described above, in the heating resistor according to the present invention, it is possible to obtain a desired specific resistance with good controllability, and it is possible to obtain an extremely small variation in the resistance value in one inkjet head.
This is because the electric circuit of the entire inkjet head can be accurately formed as designed.

In addition, the heating resistor according to the present invention is also extremely effective for a disposable cartridge type ink jet head integrally provided with an ink tank for storing the ink supplied to the heat acting surface. This is because the inkjet head of this embodiment is required to have a low running cost of the entire inkjet device to which the inkjet head is mounted. As described above, the heating resistor according to the present invention is in direct contact with the ink. This is because the heat transfer efficiency to the ink can be made good because of the constitution, so that the power consumption of the entire apparatus can be reduced and the above requirements can be easily met.

By the way, the ink jet head of the present invention may have a form in which a protective layer is provided on the heating resistor. In that case, although the efficiency of heat conduction to the ink is somewhat sacrificed, it is possible to obtain an inkjet head that is more excellent in terms of durability of the electrothermal converter and resistance change of the heating resistor due to an electrochemical reaction. From this point of view, when the protective layer is provided, it is preferable that the total layer thickness is within the range of 1000Å to 5 μm. As the protective layer, specifically, a Si-containing insulating layer made of SiO ₂ , SiN or the like provided on the heating resistor, and an Al layer provided so as to form a heat acting surface on the layer. What has it is mentioned as a preferable example.

The heater is not limited to the generation of thermal energy used for ejecting ink, but may be used as a heater for heating a desired portion in an ink jet head provided as necessary, It is particularly preferably used when such a heater is in direct contact with the ink.

By mounting the ink jet head having the above-described structure on the apparatus body and applying a signal from the apparatus body to the ink jet head, it is possible to obtain an ink jet recording apparatus capable of high speed recording and high image quality recording.

FIG. 5 is a schematic perspective view showing an example of an ink jet recording apparatus IJRA to which the present invention is applied. The driving force transmission gear 501 is interlocked with the forward / reverse rotation of the drive motor 5013.
Lead screw 500 rotating through 1,5009
The carriage HC engaging with the spiral groove 5004 of No. 5 has a pin (not shown) and is reciprocated in the directions of arrows a and b. A paper pressing plate 5002 presses the paper against the platen 5000 in the carriage movement direction. Fifty
Reference numerals 07 and 5008 denote photocouplers and a lever 5 of the carriage.
This is a home position detecting means for confirming the existence of 006 in this region and switching the rotation direction of the motor 5013. Reference numeral 5016 is a member that supports a cap member 5022 that caps the entire surface of a cartridge-type recording inkjet head IJC in which an ink tank is integrally provided. Reference numeral 5015 is a suction unit that sucks the inside of the cap through an opening 5023 in the cap. Perform suction recovery of the recording inkjet head. Reference numeral 5017 is a cleaning blade, and 5019 is a member that allows this blade to move in the front-rear direction, and these are supported by a main body support plate 5018. Needless to say, a well-known cleaning blade can be applied to this example instead of this form. Reference numeral 5012 denotes a lever for starting suction for suction recovery, which moves in accordance with movement of a cam 5020 that engages with a carriage, and movement control of a driving force from a driving motor by a known transmission means such as clutch switching. To be done. C that gives a signal to the electrothermal converter provided in the inkjet head IJC and controls the drive of each mechanism described above.
The PU is provided on the apparatus body side (not shown).

In the ink jet head and ink jet apparatus of the present invention, the parts other than the above-mentioned heating resistor can be formed by using known materials and methods.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

Example 1 One Si single crystal substrate (manufactured by Wacker) and one Si single crystal substrate (manufactured by Wacker) having a 2.5 μm thick SiO ₂ film formed on the surface were subjected to sputtering. As the sputtering substrate 603 in this case, FIG.
The deposition chamber 60 of the above-mentioned high-frequency sputtering apparatus shown in FIG.
1 set on the substrate holder 602, and 99.9% by weight
Using a composite target in which two Ir targets 607, which are Ir sheets of approximately the same purity, are placed on the Al target 606, which is a high-purity raw material as described above, co-sputtering is performed under the following conditions to obtain about 2000 Å. A thick alloy layer was formed.

Co-sputtering conditions Target area ratio Al: Ir = 37: 63 Target area 5 inch (127 mm) φ High frequency power 1000 W Substrate setting temperature 50 ° C. Film forming time 12 minutes Base pressure 2.6 × 10 ⁻⁴ Pa or less Sputtering gas pressure 0.4 Pa (argon) Further, for the film formed on the substrate with the SiO ₂ film, the Al layer which becomes the electrodes 104 and 105 (see FIG. 1) on the alloy layer is continuously switched to the target containing only Al. Was formed into a layer thickness of 6000Å by sputtering according to a conventional method, and the sputtering was completed.

After that, a photoresist is formed twice in a predetermined pattern by the photolithography technique, and once A
Wet etching of the 1-layer, and the second heating resistance layer was dry-etched by ion milling to form the heating resistor 103 and electrodes 104 and 105 in the shapes shown in FIGS. 1B and 2A. . The size of the heat generating part is 30 μm
× 170 μm, the pitch of the heat generating portions was 125 μm, and 24 heat generating portions were arranged in a row to form one group, and a plurality of this group was formed on the SiO ₂ film substrate.

Next, a SiO ₂ film is formed on this by sputtering, and thereafter, this SiO ₂ film is covered with electrodes of 10 μm on both sides of the heat generating portion by using photolithography technology and reactive ion etching. To form a protective layer 106. Heat generation part 10
The size of 9 is 30 μm × 150 μm.

The above-prepared product was subjected to a cutting process for each group to prepare a large number of ink jet head substrates, and a part of the substrates was subjected to the evaluation test described below.

In another part, FIG. 1 (a) and FIG.
In order to form the discharge port 108 and the liquid passage 111 shown in (b), a glass grooved plate 107 was joined to obtain an inkjet head.

When these ink jet heads thus obtained were mounted on a recording apparatus having a known structure and a recording operation was carried out, it was possible to perform recording with good ejection stability and good signal response, and to obtain a high quality image. I was able to. Also, the durability of use in this device was good.

(1) Measurement of film composition The composition of the material was clarified by performing EPMA (electron probe microanalysis) on the thermal action part without the protective film under the following conditions using the above-mentioned measuring device.

Acceleration voltage 15 kV Probe diameter 10 μm Probe current 10 nA However, quantitative analysis was performed only on the main constituent elements of the target as a raw material, and was attached to argon or the surface generally incorporated in the film by sputtering. It does not go to carbon or oxygen that seems to exist. In addition, the detection error of the analyzer (about 0.2% by weight) was obtained by using both quantitative analysis and qualitative analysis for all other impurities.
The following was confirmed.

(2) Measurement of film thickness Stylus type surface shape measuring instrument (TENCOR INSTRUM
It was performed by measuring the level difference using an alpha-step 200 manufactured by ENTs.

(3) Crystallinity measurement An X-ray diffraction pattern of a sample formed on a Si single crystal substrate was measured using the above-mentioned measuring device, and a crystal having a sharp peak was observed. (C), one in which no sharp peak is seen and which is considered to be in an amorphous state (A), and one in which both are considered mixed (M).
Classified into types.

(4) Measurement of specific resistance 4 probe resistance meter (K-705R manufactured by Kyowa Riken Co., Ltd.)
It was calculated from the sheet resistance value and the film thickness measured in L).

(5) Measurement of Density The weight change of the substrate before and after film formation was measured by INABA SEISAK.
It was measured with an ultramicro balance manufactured by USHO LTD, and calculated from the value, the area of the film, and the film thickness.

(6) Measurement of internal stress The warpage of two elongated glass substrates was measured before and after film formation, and the amount of change and the length, thickness, Young's modulus, Poisson's ratio, and film thickness of the glass substrates were measured. Calculated from

(7) Foaming test in low-conductivity ink The part of the device (ink jet head substrate) provided with the protective layer 106 obtained at the stage where the ejection ports and liquid paths were not formed was obtained as follows. Low conductivity ink (clear ink)
It is immersed in the external power source and the width of the electrodes 104 and 105 is 7μ.
A foaming threshold voltage (Vth) was obtained by applying a rectangular voltage of sec and a frequency of 5 kHz while gradually increasing the voltage.

Ink composition Water 70 parts by weight Diethylene glycol 30 parts by weight Ink conductivity 25 μS / cm Next, in this ink, foaming was repeated by applying a pulse voltage whose voltage was 1.1 times Vth and 24 thermal effects. Part 109
The number of applied pulses until each of them was broken was measured, and the average value thereof was calculated (hereinafter, the foaming durability test in such an ink is also commonly referred to as a "ike test"). Table 1 shows the ratios obtained by dividing the average value calculated in this example by the value of 5 times the average value calculated in the same manner as in this example in Comparative Example 2 described later.

Since the ink having the above composition has a small electric conductivity, the influence of the electrochemical reaction is small, and the main cause of the breakage is erosion due to cavitation and thermal shock, and the durability to these can be known.

(8) Foaming durability test in high conductivity ink Next, a foaming durability test was performed in the following high conductivity ink (here, black ink) in the same manner as (7). The ratio obtained by dividing the average value calculated in this example in the same manner as (7) by the value of 5 times the average value calculated by the foaming durability test with the low conductivity ink in Comparative Example 2 The results are shown in Table 1. At this time, not only the number of applied pulses but also the change in the resistance value of the heating resistor before and after applying the pulse signal was measured.

Ink composition Water 68 parts by weight Diethylene glycol 30 parts by weight Black dye (CI Food Black 2) 2 parts by weight PH adjuster (sodium acetate) Trace amount (adjusted to PH 6 to 7) Ink conductivity 2.6 mS / cm In this measurement, the ink conductivity is high, and a current also flows through the ink when a voltage is applied. Therefore, in addition to erosion due to cavitation, an electrochemical reaction is a major factor that damages the heating resistor.

(9) Step stress test (SST) The pulse width and frequency are the same as those in (7) and (8), and the pulse voltage is increased every fixed step (6 × 10 ⁵ pulses, 2 minutes). Stress test in air,
The ratio (M) between the breaking voltage (Vbreak) and the Vth obtained in (7) was obtained, and the temperature reached by the thermal action surface at Vbreak was estimated. Thereby, it is possible to know the heat resistance and the heat shock resistance in the air.

(10) Evaluation of actual ink jet head Example of printer driving condition Number of ejection ports 24 Driving frequency 2 kHz Driving pulse width 10 μsec Driving voltage 1.2 times ejection threshold voltage (Vth) Same as black ink used in ink tank test Item (i) Printing quality Characters, etc. are printed using an inkjet head and judged visually. When an extremely good print was obtained using an inkjet head, it was evaluated as ◯, when good print was obtained as Δ, and when problems such as non-ejection and blurring occurred, it was evaluated as x.

(Ii) Durability After printing about A4 size 2000 sheets using three ink jet heads for each heating element,
Three inkjet heads that produce extremely good and normal printing ○ One that produces good and normal printing with all three inkjet heads △ Any one of the three heating resistors of the inkjet heads Even when there was an abnormality such as a failure, it was rated as x.

(11) The criteria for comprehensive evaluation are shown below.

◯: Durability test result by pond test in low conductivity ink: ≧ 6 × 10 ⁷ , durability test result by pond test in high conductivity ink: ≧ 3 × 10 ⁷ , resistance Change: ≦ 5%, SST M: ≧ 1.7, and both print quality and durability evaluation results are ◯.

Δ: SST M of the evaluation items in the case of ○ above
If the value of is ≧ 1.50.

X: As a result of the pond test in the high conductivity ink, any one of the resistance change and SSTM is evaluated as less than Δ in the comprehensive evaluation, or one of the print quality and the durability is ×. in the case of.

(Examples 2 to 4) At the time of forming the heating resistor,
A device (ink jet head substrate) and an ink jet head were produced in the same manner as in Example 1 except that the area ratio of each raw material in the sputtering target was variously changed as shown in Table 1. Table 1 shows the evaluation results of the obtained devices in the same manner as in Example 1. Further, the inkjet heads produced using these devices all had good recording characteristics and durability.

(Embodiment 5) Separately from Embodiments 2 to 4, an Al target was cut, an Ir target was embedded, and I
A sputtering target in which r and Al were electrically welded was used. The area ratio of Ir to Al is shown in Table 1 from the results of Examples 1 to 4 and Comparative Examples 1 to 4 described later. A device (inkjet head substrate) and an inkjet head were produced in the same manner as in Example 1 except that this target was used. Table 1 shows the evaluation results of the obtained devices in the same manner as in Example 1. Further, the inkjet heads produced using these devices all had good recording characteristics and durability.

(Embodiment 6) The sputtering apparatus used in Embodiments 1 to 5 is modified to have a plurality of target holders in the film forming chamber, and each of the target holders has an R independently.
A film forming apparatus capable of applying F electric power was manufactured. Further, Al and Ir targets each having a purity of 99.9 Wt% or more were mounted on the two target holders of this apparatus so that the two metals could be sputtered independently and simultaneously. Using this apparatus, the same substrate as in Examples 1 to 5 was used to form a film by multi-source simultaneous sputtering under the following conditions.

[0102] Target area: 5 inches (127 mm) each φ Substrate setting temperature: 50 ° C. Film formation time: 9 minutes Base pressure: 2.6 × 10 ⁻⁴ Pa or less Sputtering gas pressure: 0.4 Pa (argon) The power applied to each target is , And was continuously changed as a linear function with respect to the film formation time.

The obtained film was analyzed and evaluated in the same manner as in Examples 1-5. With respect to the composition, separate film formation was performed under the conditions of constant initial applied power and constant applied power at the end, respectively.
It was as follows when the quantitative analysis by PMA was performed.

When the initial applied power remains constant Al: Ir = 56: 44 (1) At the end when the applied power remains constant Al: Ir = 7: 93 (2) From this fact, the film obtained above is obtained. The lower part and the upper part of the composition have the compositions as described in (1) and (2), respectively, and it is estimated that the composition continuously changes from (1) to (2) from the lower part to the upper part. . By changing the composition in the thickness direction as described above, it is possible to further improve the adhesiveness and control the internal stress.

Example 7 Using the same apparatus as in Example 6, film formation was performed under the same conditions as in Example 6 except that the applied power was changed as follows. The same analysis and evaluation as those of ~ 5 were performed.

[0106] In this case, it is considered that a laminated film composed of upper and lower two layers is obtained, and the compositions of the upper and lower layers and the lower layer are (2) and (1), respectively.

(Embodiments 8 to 12) On the layer of the heating resistor of the ink jet head substrate manufactured in the same manner as the ink jet head substrate manufactured in each of Examples 1 to 5, the above-described FIG. Using the sputtering equipment of
Except that a SiO ₂ protective layer having a thickness of 1.0 μm is provided by sputtering SiO _2, and a Ta protective layer having a thickness of 0.5 μm is further provided by sputtering Ta on the SiO ₂ protective layer. An inkjet head substrate and an inkjet head were produced in the same manner as in the example.

An evaluation test was carried out on the obtained ink jet head substrate and ink jet head in the same manner as in Example 1. As a result, an ink immersion test (pond test) was conducted as compared with the example in which a protective layer was not provided. The result of the durability test was improved little by little for the low conductivity ink and the high conductivity ink. Further, the resistance change was smaller than that in the example in which the protective layer was not provided. However, M of SST
Became smaller overall.

From the above, by providing the protective layer,
It can be seen that the durability and the resistance change mainly due to the electrochemical reaction are improved.

It is to be noted that the reason why the M of SST becomes small is that the foaming threshold voltage (Vth), which is a denominator of M, becomes large because the heat conduction efficiency to the ink is lowered by providing the protective layer. To be done. (Comparative Examples 1 to 4) A device (inkjet head substrate) was prepared in the same manner as in Example 1 except that the area ratio of each raw material in the sputtering target was variously changed when the heating resistor was formed. An inkjet head was produced.

Table 1 shows the evaluation results of the obtained devices in the same manner as in Example 1.

[0112]

[Table 1] The typical configuration and principle of an inkjet recording inkjet head and a recording apparatus according to the present invention are described in, for example, U.S. Pat. No. 4,723,129 and US Pat.
Preference is given to using the basic principles disclosed in 740,796. This method can be applied to both the so-called on-demand type and the continuous type. Especially, in the case of the on-demand type, the electric heat arranged corresponding to the sheet holding the liquid (ink) or the liquid path. By applying at least one drive signal which gives a rapid temperature rise exceeding nucleate boiling corresponding to recorded information to the converter, thermal energy is generated in the electrothermal converter, and as a result, this drive signal is generated. This is effective because bubbles can be formed in the liquid (ink) corresponding to each other. The liquid (ink) is ejected through the ejection openings by the growth and contraction of the bubbles to form at least one droplet. It is more preferable to make this drive signal into a pulse shape because bubbles can be immediately and appropriately grown and contracted, so that liquid (ink) ejection with excellent responsiveness can be achieved. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. It should be noted that U.S. Pat. No. 4,313,124, which discloses an invention relating to the rate of temperature rise of the heat acting surface
If the conditions described in the specification are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the discharge port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned specifications, The present invention also includes configurations using US Pat. No. 4,558,333 and US Pat. No. 4,459,600, which disclose configurations in which a heat acting portion is arranged in a bending region. Is. In addition, Japanese Laid-Open Patent Publication No. 123670/1984, which discloses a configuration in which a common slit is used as a discharge portion of a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy are provided. The present invention is also effective as a configuration based on JP-A-59-138461, which discloses a configuration corresponding to the ejection portion.

Further, as a full line type recording head having a length corresponding to the width of the maximum recording medium which can be recorded by the recording device, a combination of a plurality of recording heads as disclosed in the above-mentioned specification is used. The present invention can exert the above-mentioned effects more effectively, although it may have a configuration satisfying the length or a configuration as one recording head integrally formed. In addition, the ink tank is integrated into the replaceable chip-type recording head, or the recording head itself, which can be electrically connected to the device body and supply ink from the device body when it is mounted on the device body. The present invention is also effective when a cartridge-type recording head that is specially provided is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc., which are provided as a configuration of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized. If you list these specifically,
Capping means, cleaning means, pressurization or suction means, electrothermal converters or heating elements other than these, or preheating means by a combination thereof, to the recording head, preliminary ejection for performing ejection other than recording Performing the mode is also effective for stable recording.

Further, the recording mode of the recording apparatus is not limited to the recording mode only for the mainstream color such as black, but the recording head may be integrally formed or a plurality of combinations may be used. The present invention is also extremely effective for an apparatus provided with at least one of full color by color mixing.

When the alloy material according to the present invention is used, resistance to impact of cavitation, resistance to erosion due to cavitation, electrochemical stability, chemical stability, oxidation resistance, dissolution resistance, heat resistance, thermal shock resistance. ,
It is possible to obtain an inkjet head and an inkjet head device including an electrothermal converter having a heating resistor having excellent mechanical durability and the like. In particular, it is possible to obtain an inkjet head and an inkjet device in which the heat generating portion of the heating resistor is in direct contact with the ink in the ink path. In the ink jet head and the ink jet device having this structure, the heat energy generated from the heat generating portion of the heat generating resistor can be directly applied to the ink, so that the heat conduction efficiency to the ink is good. Therefore, the power consumption of the heating resistor can be suppressed to a low level, and the temperature rise of the inkjet head (temperature change of the inkjet head)
Since it is possible to reduce significantly, it is possible to avoid occurrence of image density change due to temperature change of the inkjet head. Further, it is possible to obtain a better responsiveness to the ejection signal applied to the heating resistor.

Further, in the heat generating resistor according to the present invention, it is possible to obtain a desired specific resistance with good controllability and with a very small variation in the resistance value in one ink jet head.

Therefore, according to the present invention, it is possible to obtain an ink jet head and an ink jet device which are capable of ejecting ink in a much more stable manner than the conventional ones and which are excellent in durability.

The ink jet head and the ink jet apparatus having the above-mentioned excellent characteristics are very suitable for high speed recording and high image quality due to the multi-ejection.

In the embodiments of the present invention described above, the ink is described as a liquid, but it is an ink that solidifies at room temperature or below, and is softened or liquid at room temperature, or the ink itself is 30 in the above ink jet. It is common to adjust the temperature within a range of ℃ to 70 ℃ to control the temperature of the ink so that the viscosity of the ink is within the stable ejection range. good. In addition, it is possible to prevent the temperature rise due to thermal energy from being positively used as the energy for changing the state of the ink from the solid state to the liquid state, or to use the ink that solidifies in the standing state for the purpose of preventing ink evaporation. However, in any case, by applying heat energy such as ink that is liquefied by applying heat energy according to a recording signal and is ejected as an ink liquid or that has already started to solidify when it reaches a recording medium. The use of an ink having a property of liquefying for the first time is also applicable to the present invention. In such a case, the ink is disclosed in JP-A-54-5684.
No. 7 or JP-A-60-71260, a mode in which the porous sheet is opposed to the electrothermal converter in the state of being held as a liquid or a solid in the recess or through hole of the porous sheet. Also good. In the present invention,
The most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0122]

As described above, according to the present invention, the heating resistor is made of a non-single crystal material containing two elements of Ir and Al in a specific composition ratio, thereby improving durability and stability. In addition, resistance to cavitation impact, resistance to cavitation erosion, mechanical durability, chemical stability, electrochemical stability, resistance stability, heat resistance, oxidation resistance, dissolution resistance and There is an effect that an improved inkjet head having excellent thermal shock resistance and excellent thermal conductivity can be obtained.

Further, it has a structure in which the heating resistor is in direct contact with the recording liquid, and is stable and always on-demand even after repeated use for a long time.
There is an effect that an improved ink jet head can be provided which immediately responds to the signal in d) to efficiently transfer the heat energy to the recording liquid to eject the ink, thereby providing an excellent recorded image.

Further, the heating resistor has a structure in which the heating resistor is brought into direct contact with the recording liquid, the power consumption by the heating resistor is kept low, the temperature change of the ink jet head is made extremely small, and the heating is repeated for a long time. There is an effect that ink can always be stably ejected even during use, and the obtained image can have no density change due to temperature change of the inkjet head.

Further, there is an effect that it is possible to provide an ink jet device having each of the above effects.

[Brief description of drawings]

FIG. 1A is a schematic front view of an inkjet head according to a first embodiment of the present invention as viewed from a discharge port side, FIG.
[Fig. 4] is a sectional view taken along line XY in (a).

FIG. 2A is a schematic plan view of an inkjet head substrate at a stage where a heating resistor layer and electrodes of the first embodiment are provided, and FIG. FIG. 3 is a schematic plan view of an inkjet head substrate at a stage where layers are provided.

FIG. 3 is a cross-sectional view showing the configuration of the main parts of a second embodiment of the inkjet head of the present invention.

4A and 4B are a schematic top view and a sectional view, respectively, of a third embodiment of an inkjet head of the present invention.

FIG. 5 is an external perspective view showing an example of an inkjet device according to the present invention.

FIG. 6 is a schematic cross-sectional view showing an example of a high-frequency sputtering apparatus used for producing a film such as a heating resistor according to the present invention.

[Explanation of symbols]

101,301,603 substrate 102,302 Lower layer 103, 303 heating resistor layer 104, 105, 304, 305 electrodes 106 protective layer 107 grooved plate 108 outlet 109,309 Thermal action surface 410 Discharge plate 412 support member 601 deposition chamber 602 substrate holder 603 board 604 shutter plate 605 target holder 606 Al target 607 Ir target 608 rotating shaft 609 Insulator 610 exhaust pipe 611 Exhaust pump 612 gas supply pipe 613 Flow control valve 614 Matching Box 615 RF power supply 616, 617 conductor 618 Protective wall 619 vacuum gauge 5000 platen 5002 Paper holding plate 5004 spiral groove 5005 lead screw 5006 lever 5007,5008 Photo coupler 5009, 5011 Driving force transmission gear 5013 Drive motor 5015 Suction means 5016 Home position detection means 5017 cleaning blade 5018 Body support plate 5019 member 5020 cam 5022 Cap member 5023 Opening in the cap

Continued front page    (72) Inventor Isao Kimura             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation

Claims (36)

[Claims] 1. An ink jet head having an electrothermal converter having a heating resistor for generating heat energy by directly applying heat energy to the ink on the heat acting surface to eject the ink. In the substrate, the heating resistor is made of a material containing at least Ir and Al in the following composition ratios. 54 atom% ≦ Ir ≦ 95 atom% 5 atom% ≦ Al ≦ 46 atom% 2. The inkjet head substrate according to claim 1, wherein the constituent material of the heating resistor is a non-single crystalline substance. 3. The inkjet head substrate according to claim 2, wherein the non-single crystalline substance is a polycrystalline substance. 4. The ink jet head substrate according to claim 1, wherein the material forming the heating resistor is Ar, O, or impurities as impurities.
A substrate for an inkjet head, which contains at least one selected from the group consisting of C, N, Si, B, Na, Cl and Fe. 5. The inkjet head substrate according to claim 1, wherein the material forming the heating resistor is such that the distribution state of elements contained in the thickness direction of the heating resistor is changed. Characteristic inkjet head substrate. 6. The inkjet head substrate according to claim 1, wherein the material forming the heating resistor has a structure in which a plurality of layers are laminated. 7. The inkjet head substrate according to claim 1, wherein the electrothermal converter has a pair of electrodes on the heating resistor for contacting the heating resistor to conduct electricity. An inkjet head substrate. 8. The inkjet head substrate according to claim 1, wherein the electrothermal converter has a pair of electrodes below the heating resistor for contacting the heating resistor to conduct the current. Characteristic inkjet head substrate. 9. The inkjet head substrate according to claim 1, wherein the heat acting surface is formed by a heating resistor. 10. The inkjet head substrate according to claim 1, wherein the heat acting surface is formed by a protective layer on the heating resistor. 11. The inkjet head substrate according to claim 1, wherein the protective layer includes a Ta layer forming a heat acting surface and a Si-containing insulating layer interposed between the Ta layer and the heating resistor. A substrate for an inkjet head, which comprises: 12. The inkjet head substrate according to claim 1, wherein the heating resistor layer has a thickness of 300Å to 1 μm. 13. The inkjet head substrate according to claim 1, wherein the heating resistor layer has a thickness of 1000 Å to 5000 Å. 14. An electrothermal converter having a heating resistor for generating heat energy by directly applying heat energy to the ink on the heat-acting surface to discharge the ink is provided in the ink passage. An ink jet head provided along with the above, wherein the heating resistor is made of a material containing at least Ir and Al in the following composition ratios. 54 atom% ≦ Ir ≦ 95 atom% 5 atom% ≦ Al ≦ 46 atom% 15. The inkjet head according to claim 14, wherein the constituent material of the heating resistor is a non-single crystalline substance. 16. The inkjet head according to claim 15, wherein the non-single crystalline material is a polycrystalline material. 17. The ink jet head according to claim 14, wherein the material forming the heating resistor is Ar, O, or
An ink jet head containing at least one selected from the group consisting of C, N, Si, B, Na, Cl and Fe. 18. The ink jet head according to claim 14, wherein the material forming the heating resistor has a distribution state of elements contained in the thickness direction of the heating resistor changed. Inkjet head to do. 19. The inkjet head according to claim 14, wherein the material forming the heating resistor has a structure in which a plurality of layers are laminated. 20. The ink jet head according to claim 14, wherein the electrothermal converter has a pair of electrodes on the heating resistor for contacting the heating resistor to conduct electricity. Inkjet head. 21. The ink jet head according to claim 14, wherein the electrothermal converter has a pair of electrodes under the heating resistor for contacting the heating resistor to perform the energization. Inkjet head to do. 22. The ink jet head according to claim 14, wherein the heat acting surface is formed by a heating resistor. 23. The ink jet head according to claim 14, wherein the heat acting surface is formed by a protective layer on the heat generating resistor. 24. The ink jet head according to claim 14, wherein the protective layer has a Ta layer forming a heat acting surface and a Si-containing insulating layer interposed between the Ta layer and the heating resistor. Inkjet head characterized by. 25. The inkjet head according to claim 14, wherein the thickness of the layer of the heating resistor is 300Å to 1 μm. 26. The inkjet head according to claim 14, wherein the heating resistor layer has a thickness of 1000 Å to 5000 Å. 27. The inkjet head according to claim 14, wherein the direction of ejecting the ink and the direction of supplying the ink to the heat acting surface are substantially the same. 28. The inkjet head according to claim 14, wherein the direction of ejecting the ink and the direction of supplying the ink to the heat acting surface are substantially perpendicular to each other. . 29. The inkjet head according to claim 14, wherein a plurality of ejection openings for ejecting ink are provided in correspondence with a width of a recording region of a recording member. 30. The inkjet head according to claim 29, wherein a plurality of discharge ports of 1000 or more are provided. 31. The ink jet head according to claim 30, wherein a plurality of ejection ports of 2000 or more are provided. 32. The inkjet head according to claim 14, wherein the functional element relating to ink ejection is structurally provided inside the surface of the inkjet head substrate. 33. The ink jet head according to claim 14, wherein the ink jet head is a cartridge type integrally provided with an ink tank for storing the ink supplied to the heat acting surface. 34. An electrothermal converter comprising a heating resistor for generating the thermal energy used for ejecting the ink by directly applying the thermal energy to the ink on the heat acting surface, and the electric heat. An inkjet device comprising a means for applying a signal to a converter, wherein the heating resistor is made of a material containing at least Ir and Al in the following composition ratios. 54 atom% ≦ Ir ≦ 95 atom% 5 atom% ≦ Al ≦ 46 atom% 35. The ink jet apparatus according to claim 34, which performs color recording. 36. The ink jet apparatus according to claim 34, wherein the means for applying a signal to the electrothermal converter is a control circuit of the ink jet apparatus.