JPS5996971A - Liquid injection recorder - Google Patents

Abstract

PURPOSE:To enable recording an image excellent in the resistance to repeated use and liquid with a high resolution and a high quality at a high speed by employing a specified metal for a heat generating resistance layer composing an electrothermal conversion body for generating heat energy. CONSTITUTION:A liquid injection recorder 1 is equipped with a discharge port provided for injecting a liquid to form fly liquid drops, a heat action section 7 communicated with the discharge port (orifice) to have heat energy acting on the liquid to form flying liquid drops and an electrothermal conversion body 2 as means of generating heat energy. A heat generating resistance layer 11 composing the electrothermal body 2 is provided as a thin layer of Ta or alloy of Ta. The content of Ta contained in the alloy containing Ta preferably exceeds 20mol%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid jet recording device that performs recording using 14-dimensional droplets formed by discharging liquid from a discharge port, and in particular, a liquid jet recording device that utilizes thermal technology. The present invention relates to a liquid jet recording device.

There are various types of liquid jet recording devices, and among them, for example, the liquid jet recording devices of the type disclosed in OLS No. 2843064, OLS No. 2944005, and USP No. 4335389 are high-speed color printers. To facilitate recording, the recording head, which is the main part of the output section, has ejection openings (orifices) arranged in a height of 7 [ffi] for ejecting liquid for recording and forming flying droplets. It's expensive to be able to do it! At the same time, the recording head can be made more compact as a whole, and it is suitable for industrial production.In the semiconductor field, the IC technology has made significant technological advances and improved reliability. ℃・ru has recently attracted a lot of attention due to the advantages of micro-processing technology, such as the fact that it is easy to make it longer by making full use of it.

The characteristic recording head of the liquid jet recording apparatus described above is provided with an electrothermal converter as a means for ejecting liquid from an orifice and generating thermal energy 'i 'tb for forming flying droplets. ing.

The electrothermal converter is capable of making the generated thermal energy act on the liquid efficiently and turning on and off the heat action on the liquid.
In order to increase the response speed, etc., it is considered desirable to have a structure in which the heat acting part is connected to the orifice so as to be directly fused to the liquid.

According to Hyakunen et al., the above-mentioned electrothermal converter basically consists of a heating resistor that generates heat when energized and a pair of electrodes for energizing the heating resistor, so it is called a heating resistor. If the recording liquid is in direct contact with the liquid, depending on the electrical resistance of the recording liquid, electricity may flow through the liquid, the liquid itself may be electrolyzed by the flow of electricity through the liquid, or the heating resistor may When the heating resistor is energized, the heating resistor reacts with the liquid, resulting in a change in resistance value due to corrosion of the heating resistor itself, damage or destruction of the heating resistor, or even damage caused by the heating resistor. The thermal action of the liquid, preferably vapor bubbles, may cause cracks to form in a portion of the heating resistor, causing it to be destroyed.

Therefore, in the past, alloys such as NiCr and ZrB
2.

The heating resistor is made of an inorganic material such as metal boride such as HfB2, which has relatively excellent properties as a heating resistor material, and 5i02 is used on the heating resistor made of the material.
By providing a protective layer (upper layer) made of a material with excellent oxidation resistance, such as the It was proposed to try to improve the durability against repeated use.

A liquid jet recording apparatus having a recording head 7 equipped with an electrothermal transducer having the above-mentioned structure uses a relatively low liquid (11L) with a relatively low air conductivity of 1.1 as a colored liquid for recording.
(e.g., using distilled water or alcohol as the liquid medium)
Although it has excellent oxidation resistance and is satisfactory in terms of durability for repeated use, it has a high content of Na ions, etc. In the case of using liquids from other countries, the durability against repeated use and the resistance to change over time were insufficient. Therefore, there are restrictions on the selection of the recording liquid to be used, which poses an obstacle, especially when performing multicolor or natural color recording.

Furthermore, even when a protective layer is provided on the heating resistor as described above, it is impossible to substantially completely prevent liquid from penetrating toward the heating resistor due to defects in the preservation layer itself that occur during layer formation, for example. This is extremely difficult in terms of reproducibility and mass production. In addition, in the case of so-called high-density multi-orifice construction, in which liquid channels (nozzles) are provided with a large number of heat-acting parts at high density, it is necessary to use at least as many electrothermal converters as there are liquid channels. Since it is necessary to provide the protective layer at one time, the influence of defects in the protective layer on the manufacturing yield of the electrothermal converter is a big problem, including the manufacturing cost.

Therefore, even if there is no π-holding layer and the heating resistor is in direct contact with the recording liquid, the liquid resistance, repeatability of use, and
There is a strong desire to develop a liquid jet recording device equipped with an electrothermal converter that has excellent mechanical impact resistance, Mf resistance, and gas chemical reactivity.

The present invention has been made in accordance with the above 811 points, and its main object is to provide an excellent liquid jet recording apparatus that solves all of the problems in the conventional art.

Another object of the invention is liquid resistance and mechanical impact resistance.

It is an object of the present invention to provide a liquid jet recording device that has excellent repeatability and electrochemical reactivity resistance.

The liquid jet recording device of the present invention has an ejection port provided for ejecting liquid to form flying droplets, and an ejection port (orifice) K communicating with the ejection port (orifice) K to eject liquid to form flying droplets. It is equipped with a heat acting part where energy acts on the liquid, and an electrothermal converter as a means for generating the thermal energy, and the heating resistance layer constituting the electrothermal converter is made of Ta or a Ta-containing alloy. It is characterized by becoming.

The liquid jet recording device of the present invention configured as described above has excellent durability against repeated use, rigidity, and fidelity and reliability of response to recording signals, and is capable of producing high-resolution, high-quality images at high speed. It can be recorded. .

Furthermore, when the electrothermal transducer is configured so that the heating resistor is in direct contact with the recording liquid, the thermal energy generated by the heating resistor effectively acts on the recording liquid, so that the electric The drive voltage threshold for driving the heat converter is low,
In addition, the actual driving voltage for stably forming flying droplets is low, making it easy to save energy.

Furthermore, since there is a wide range of recording liquids to choose from, it is possible to easily provide a variety of desired colors and natural colors.

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

FIG. 1(,) is a front partial view of the main part of the liquid jet recording device of the present invention as seen from the orifice side, and FIG. 1(b) is the portion indicated by the dashed line XY in FIG. 1(&). FIG.

The recording head 1 shown in the figure has a grooved surface in which a predetermined number of grooves of a predetermined width and depth are provided at a predetermined linear density on the surface of a substrate 6 on which an electrothermal transducer 2 is provided. It has a structure in which an orifice 5 and a liquid discharge part 6 are formed by joining so as to be covered with a plate 4. In the case of the liquid jet recording device shown in the figure, it is shown as having a plurality of slip orifices 5, but the present invention is of course not limited to this, and can be applied to a recording device with a single orifice. Also falls within the scope of the present invention.

The liquid discharge part 6 has an orifice 5 at its end for discharging liquid to form flying droplets, and an electrothermal converter 2).Thermal energy generated acts on the liquid to generate vapor bubbles. , and has a heat acting part 7 which causes a rapid state change due to expansion and contraction of its volume.

The heat acting part 7 is located above the heat generating part 8 of the electrothermal converter 2, and has a heat acting surface 9 that contacts the liquid of the heat generating part 8 as its bottom surface.

The heat generating section 8 includes a lower layer 10 provided on the substrate 3 and a heating resistor layer (heating resistor) 11 provided on the lower layer 10.
, and an upper layer 12 provided on the heating resistance layer 11 as necessary. The heating resistor layer 11 is provided with electrodes 13 and 14 on its surface for supplying electricity to the layer 11 in order to generate heat. The electrode 16 is a common electrode for the heat generating section of each liquid discharging section, and the electrode 14 is a selection electrode for selectively generating heat in the heat generating section of each liquid discharging section. It is located along the road.

The upper layer 12 isolates the heating resistance layer 11 from the liquid in the liquid discharge part 6 in order to chemically and physically protect the heating resistance layer 11 from the liquid used, and also connects the electrode 1 through the liquid.
It also has a protective function for the heat generating resistive layer 11 to prevent short circuits between the heat generating resistive layer 11 and the heat generating resistive layer 11 .

The upper layer 12 has the above-mentioned functions, but
The heat generating resistance layer 11 in the liquid jet recording device of the present invention is
Since it has the characteristics described above, it is not necessarily necessary to provide it if there is no possibility that the electrodes 13, 141i8 are electrically shorted through the liquid, and even if there is the above-mentioned hybridization. However, there is no need to provide it on the heat generating resistor layer 11, and the above-mentioned 1 and 2 positions can be completely eliminated by simply covering the surfaces of the electrodes 13 and 14.

The lower layer 10 mainly has a heat flow control function.

That is, when the flying droplets are formed (1), the heat generated in the heat generating resistor layer 11 is transferred to the heat acting portion 7 rather than being conducted toward the substrate 6 side.
The rate of conduction toward the side is increased as much as possible, and after the flying droplets are formed and the power to the clogging heat generating resistor layer 11 is turned off, the heat in the heat acting part 7 and the heat generating part 8 is quickly transferred. This is provided so that the liquid in the heat acting section 7 and the generated bubbles are rapidly cooled by being discharged to the substrate 3 side.

The liquid jet recording device of the present invention can be made more excellent by designing the lower layer 10 such that it can fully exhibit the above-mentioned functions in relation to the heating resistor layer 11 and the substrate layer.

That is, when the flying droplets are formed, the proportion of the heat flow towards the heat acting part Z side is as large as possible, and when the power to the heating resistor layer 11 is turned off, the proportion of the heat flow towards the substrate 6 side is as large as possible. By increasing the ratio of heat flow as much as possible, we aim to improve the efficiency of droplet ejection energy, high thermal response, and continuous repeatable droplet ejection, improve the droplet formation frequency, and equalize the amount of droplets. , stabilization of droplet flight direction, uniformity of droplet initial flight speed,
and the fidelity and reliability of the response to the recorded signal is provided as a thin layer of Ta (tantalum) or a Ta-containing alloy, like the above-mentioned exhaust tongue.

In the present invention, effective partner materials for Ta to form the Ta-containing alloy are Al (aluminum), Sl (silicon), and transition metals. Examples of transition metals include metals belonging to the fourth period of the periodic table, namely T1 (titanium),
■ (vanadium), Or (chromium), Mn (Y
metals belonging to the 5th period of the periodic table, such as Nb (=op), Mo (molybdenum), P (
Metals belonging to the 6th period of the periodic table, such as L (palladium),
For example, Hf (/-fnium), W (tungsten),
Preferred metals include Pt (platinum) and Au (gold).

The metals that are the mating materials for these Ta-containing alloys are not limited to one type, and two or more types may be used in order to obtain the maximum desired characteristics. That is, in the present invention, the Ta-containing alloy may be a multi-element system, such as a binary system, a quinary system, and, in some cases, a quaternary system or more.

When using a multi-element system of 6 or more elements as an elemental Ta-containing alloy, it is better to select metals that belong to the same group in the periodic table, but it is better to select metals of different types depending on the purpose. This is preferable because a metal with good physical properties can be obtained.

In the present invention, an example of a combination that is particularly preferably used as a Ta-containing alloy is Ta-AllXTa-B1
Ta-Mo) Ta-wXTa-Co, binary alloys such as Ta-Ni, Ta-Ni-1'J, Ta-Ni-Mo
, Ta-N1-(3r, Ta-Or-Mo, T
a-0r-Al, Ta-0r-W, Ta-8i
-6-element alloys such as W, Ta-Ni-Al -W, Ta
Examples include quaternary alloys such as -W-hl-3i and Ta-N1-W-8i.

In the present invention, the content rate of Ta contained in the Ta-containing alloy is determined by the type of partner metal, and when there are multiple partner metals,
It is determined as desired depending on the content ratio of the other metals, etc., so as to obtain the heat generating resistive layer 11 that meets the purpose of the present invention, but it is desirable that the content is less than 100 mo1%. It is desirable that this is done.

In the present invention, the thickness of the heating resistance layer 11 is determined based on the characteristics of the material, so that appropriate thermal energy is effectively generated.
It is desirable that the method be determined as appropriate depending on the type, content rate, flying droplet formation characteristics required for the device itself, etc.

In the present invention, the heating resistance layer 11 made of a Ta-containing alloy
If it is a desired partner metal of Ta, for example Al, place an A7 piece with the desired surface shape on the Ta target, and apply Co-8up.
It is preferable to form it by ttsr (co-sumepatta).

Next, we will briefly explain the manufacturing method and form of the liquid jet recording device manufactured in the examples and comparative examples of the present invention described below. A heating resistor mounting board was created in the following manner.

After forming the heat generating resistor layer 11 and the aluminum electrode layer on the lower layer 10 of the alumina substrate 6 which also serves as the lower layer N10, selective etching is performed to form a layer with a width of 40 μm and a length of 200 μm, for example.
Heating resistors 11-1 to 1l-6e##1 were formed.

In addition, after forming the selective electrode 14 and the common electrode 13 by etching, a retention layer (upper layer) 12 was laminated on the surface of each electrode and each heat generating resistor, if necessary.

In addition to the grooves, a grooved plate is formed by cutting a plurality of grooves (for example, width 40 μm, depth 40 μm) and a groove serving as a common ink chamber (not shown) in a glass plate using a micro cutter. I also created board 4 〇 Created in this way 1
The heat generating resistor installation board and the grooved plate are joined together after the heat generating resistor and the groove are properly aligned, and furthermore, the heat generating resistor installation board and the grooved plate are bonded together, and the liquid ink is introduced into the common ink chamber from an ink supply section (not shown). An ink introduction tube (not shown) was also connected to complete the recording device.

Further, this recording device was provided with a lead substrate having lead α poles (common lead area pole and selection lead electrode) connected to the aforementioned selection electrode and common electrode.

In the liquid jet recording device having the above configuration, the upper J-chip
As, 5iOz 1, Dp/*thickness, Ta2050
．． In the case where a thin layer with a thickness of 5/2" was laminated on each heat generating resistor layer 11, a drive voltage margin of 1.5 to 1.9 times the foaming threshold voltage was obtained. This means that the heat generating resistor layer 1
It is shown that the heat resistance is further improved by providing the upper layer 12 compared to the case of a system in which the upper layer 12 is exposed to the liquid.

At this time, the system without the upper layer 12 has a driving voltage margin of about 1.6 times the foaming threshold voltage, which is shown to be superior to the conventional system.

Similar evaluations were conducted using a silicon wafer as the substrate 6 in addition to the alumina substrate described above, and as the lower part M10, a 2 to 5μ SiO2 layer formed by thermally treating the surface of the silicon wafer. I did it and got similar good results.

Further, as the substrate 6, in addition to those used in the embodiments, glass, ceramics, heat-resistant planutic, etc. can also be used.

In addition to Al, electrode materials include Al-Cu, Al
-8i etc. can be used, but when using these materials, in order to isolate between the electrode and the liquid, for example, a tympanic membrane made of photosensitive heat-resistant resin is cured, excluding the heat-active surface part. It is preferable to knead the electrode and the area around the electrode.

Embodiment A liquid jet recording apparatus (sump hib) having the configuration described above is used.
1-1 to 14-4) (Number of liquid channels ioo, - one pneumatic converter per liquid channel), - 5X10 per electrothermal converter
611J of reliability was determined by counting the number of failed heating resistors on the face after pulse driving for 1000 times.The results are shown in the table below.

[Brief explanation of the drawing]

FIG. 1(a) is a partial front view from one orifice side of a preferred embodiment of a liquid jet recording head to which the present invention is applied, and FIG. 1(b) is a point in FIG. 1(a). FIG. 3 is a partial cross-sectional view taken along a portion indicated by a chain line XY. 1...Liquid jet recording device, 2...Electrothermal converter, 6...Substrate, 4...Grooved sales, 5...
・・・■・・・Heating resistance layer, 12...Fist/upper layer, 1
3... Common electrode, 14... Selection electrode. Director')

Claims (2)

[Claims] (1) An ejection port provided for ejecting liquid to form flying droplets, and a place communicating with the ejection port where thermal energy acts on the liquid to form flying droplets. and an electrothermal converter as a means for generating the thermal energy, and a heat generating resistance layer constituting the electrothermal converter is made of Ta or a Ta-containing alloy. Recording device. (2) The liquid jet recording device according to claim 1, wherein the Ta content is 20 mol or more.