JPS59135167A - Liquid jet recorder - Google Patents

Abstract

PURPOSE:To provide the titled apparatus excellent in the liquid resistance, resistance to mechanical impact, repeated use, especially stability of the resistance value and resistance to electrochemical reactivity by having a heat generating resistance layer composing an electrothermal transducing element made of a specified oxide. CONSTITUTION:A heat generating resistance layer 11 is provided as thin layer made up of an In oxide as main component and an oxide containing at least one element selected from among V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Zr, Nb, Mo, Ru, Pd, Cd, Sb, Hf, Ta, W, Re, Au and Bi. The rate of the oxide as additive is preferably 10mol% or more, most preferably more than 20mol% and the rate of the In oxide desirably more than 50mol%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid jet recording device that performs recording using flying droplets formed by discharging liquid from a discharge port, and particularly relates to a liquid jet recording device that uses thermal energy. .

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 as follows: High-speed color recording is easy, and the recording head, which is the main part of the output section, has a high density array of ejection ports (orifices) for ejecting recording liquid and forming flying droplets. Because of this, it is possible to obtain high resolution, and at the same time, the recording head can be made more compact as a whole, and is suitable for mass production. Recently, it has been attracting a lot of attention because it is easy to make it long by making full use of the advantages of micro-processing technology.

The characteristic recording head of the above-mentioned liquid jet recording apparatus is provided with an electrothermal transducer as means for generating thermal energy for ejecting liquid from an orifice to form flying droplets.

The electrothermal converter is capable of efficiently applying the generated thermal energy to the liquid, and of controlling the ON-OF of the thermal effect on the liquid.
In order to increase the F 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 in direct contact with the liquid.

However, 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. If the resistor is in direct contact with the liquid, depending on the electrical resistance of the recording liquid, electricity may flow through the liquid, or the liquid itself may electrolyze or generate heat due to the flow of electricity through the liquid. When the resistor is energized, the heating resistor reacts with the liquid, causing a change in resistance value due to corrosion of the heating resistor itself, and even damage or destruction of the heating resistor, or even damage to the heating resistor. The surface of the heating resistor may be damaged or a portion of the heating resistor may be cracked due to mechanical shock due to a sudden change in the state of the liquid, preferably including the generation of vapor bubbles, due to the thermal action generated by the heating resistor. In some cases, it may occur or be destroyed.

For this reason, in the past, alloys such as NiCr and Zrf
32. The heating resistor is made of an inorganic material having relatively excellent properties as a heating resistor material, such as metal boride such as HfB2, and 81
By providing a protective layer (upper layer) made of a material with excellent oxidation resistance such as 02, the heating resistor is prevented from coming into direct contact with the liquid, solving the above problems and improving reliability. It has been proposed to improve the durability and durability for repeated use.

Of course, a liquid jet recording apparatus having a recording head provided with an electrothermal converter having the above-mentioned configuration uses a colored liquid for recording and a liquid with relatively low electrical conductivity (for example, a liquid). When using distilled water or alcohol as a medium), it has excellent oxidation resistance and is satisfactory in terms of repeated use durability, but it has a high content of Na ions etc. When a recording liquid or an electrolyte liquid with high conductivity is used, the durability against repeated use and the resistance to change over time are 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 has been proven that liquid infiltration toward the heating resistor is virtually completely prevented due to defects in the protective layer itself that occur during layer formation, for example. sex.

This is extremely difficult in terms of mass production. In other words, a liquid flow path (nozzle) that has a large number of high-density heat-acting parts as part of its configuration.
In the case of so-called high-density multi-orifice,
Because it is necessary to provide at least as many electrothermal converters as there are liquid flow channels at one time, the impact of failures due to defects in the protective layer on the manufacturing yield of electrothermal converters is a major problem, including in terms of manufacturing costs. be. Therefore, even if there is no protective layer and the heat-generating resistor is in direct contact with a recording liquid, the liquid resistance and
There is a strong desire to develop a liquid jet recording device equipped with an electrothermal converter that is excellent in repeatability of use, mechanical shock resistance, and electrochemical reaction resistance.

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

Another object of the present invention is to provide a liquid jet recording device that is excellent in liquid resistance, mechanical shock resistance, repeated use, particularly resistance value stability, and electrochemical reaction resistance.

The liquid jet recording device of the present invention has an ejection port provided for ejecting liquid to form flying droplets, and a discharge port (orifice) that communicates with the ejection port (orifice) 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 a heating resistance layer constituting the electrothermal converter is made of indium (In) oxide. is the main component, and V I C'? M
n, Fe, Co, Ni, Cu, Z
n, Ga, Zr, Nb, Mo.

Ru, Pd, Cd, 8E1, Hf,
It is characterized by being formed of an oxide containing at least one element selected from the group consisting of Ta, W, ELe, Au, and Bi.

The liquid jet recording device of the present invention configured as described above has the following features:
It has excellent durability against repeated use, liquid resistance, and fidelity and reliability of response to recording signals, and can record high-resolution, high-quality images at high speed.

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 perform color recording in desired multi-colors and natural colors.

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

FIG. 1(a) is a partial front 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 indicated by the dashed line X'Y in FIG. 1(a). FIG. 3 is a partial cross-sectional view of the product when cut in sections.

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 constant linear density on the surface of a substrate 30 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 (Ic j-). The liquid jet recording device shown in the figure is shown as having a plurality of orifices 5, but the present invention is of course not limited to this, and can also be applied to a recording device with a single orifice. This falls within the scope of the present invention.

The liquid discharge part 6 has an orifice 5 at its terminal end for discharging liquid to form flying droplets, and thermal energy generated by the electrothermal converter 2 acting on the liquid to generate vapor bubbles. It 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 portion 8 includes a lower layer 101 provided on the substrate 3 and a heat generating resistor layer (heat generating resistor) 1 provided on the lower portion W10.
1. An upper layer 12 is 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 13 is an electrode common to the heat generating part of each liquid discharge part, and the electrode 14 is a selection electrode for selectively generating heat in the heat generating part of each liquid discharge part,
It is provided along the flow path of the liquid discharge section.

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 has a protective function of the heat generating resistor layer 11 to prevent short circuit between 3 and 14.

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 above-mentioned characteristics, it is not necessarily necessary to provide it if there is no risk of electrical short circuit between the electrodes 13 and 14 through the liquid, and even if there is the above-mentioned concern, The above-mentioned concerns can be completely eliminated by simply covering the surfaces of the electrodes 13 and 14 without necessarily providing them on the heating resistor layer ll.

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

That is, when forming flying droplets, the proportion of heat generated in the heat generating resistor layer 11 being conducted toward the heat acting part 7 side is as high as possible than being conducted toward the substrate 3 side, and the flying droplets are After the droplets are formed and the power to the clogging heat generating resistor layer 11 is turned off, the heat in the heat acting section 7 and the heat generating section 8 is quickly transferred to the substrate 3.
It is provided to rapidly cool the liquid and generated air bubbles in the heat acting part 7 by being discharged to the 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 heat generating resistor layer 11 and the substrate 3.

That is, when the flying droplets are formed, the proportion of the heat flow to the heat acting part 7 side is as large as possible, and when the power to the heating resistor layer 11 is turned off, the heat flow rate to the substrate 3 side is as large as possible. By increasing the ratio of the flow rate as much as possible, we can improve the efficiency of droplet ejection energy, high thermal response, and continuous repeatable droplet ejection, improve the droplet formation frequency, and make the droplets uniform. Stabilization of droplet flight direction, uniformity of droplet initial flight speed,
The heat-generating resistive layer 11 in the liquid jet recording apparatus of the present invention can more effectively improve the fidelity and reliability of the response to recording signals.
As mentioned above, the main component is In oxide, V, Cr
, Mn, Fe, Co, Ni, Cu
, Zn, Ga, Zr.

Nb, Mo, Ru, Pd, Cd',
Sb, Hf, Ta, W, Re, A
It is provided as a thin layer formed of an oxide containing at least one element consisting of u + Bi.

In the present invention, the number of oxides to be added is not limited to one type, and two or more types may be mixed in order to obtain the desired characteristics to the maximum.

In the present invention, the ratio of the oxide added is preferably 10 mo7? % or more, preferably 15m01! %
Above, the optimal value is 2 Q mol! % or more is desirable.

Further, it is desirable that the content of h oxide, which is the main component, is 50 moz% or more.

Examples of particularly preferably used additive oxides in the present invention include vanadium oxide (e.g. V2O,)
, oxide oxide (e.g. EvaCr, 0.), cobalt oxide (e.g. Coo), nickel oxide (e.g. N1p), zirconium oxide (e.g. ZrO□), antimony oxide (e.g.
For example, sb, 03), tantalum oxide (for example, Ta, 0.
), tungsten oxide (eg, WO, ), bismuth oxide (eg, Bi2O,), and the like. Furthermore, chemical stability can be improved by adding two or more types of the above oxides.

In the present invention, even if a trace amount (5 at % or less) of elements other than those mentioned above is contained in the heating resistance layer 11, no deterioration in performance is observed, so there is no problem with the mixing of other elements to this extent.

In the present invention, the content of oxygen contained in the oxide is
The type of mating metal and, if there is a plurality of mating metals, the content ratio of the mating metals, etc., are determined as desired so as to obtain a heat generating resistor layer weight 1 that meets the purpose of the present invention. In view of the chemical stability of the surface state and the stability of specific resistance, the content of oxygen contained in the entire film constituting the heating resistance layer 11 is 70 atomic (at)% or less based on the total atoms. is desirable.

In the present invention, the thickness of the heating resistance layer 11 is determined based on the characteristics of the constituent materials so that appropriate thermal energy can be effectively generated.
The number of participants is determined as appropriate depending on the type, content rate, flying droplet formation characteristics required for the device itself, etc., but preferably 500 or more people.
The thickness is preferably about 10μ, and most preferably 2000λ to 5μ.

In the present invention, the heating resistance layer 11 made of an oxide uses an oxide target which is a desired main component and an oxide heret for addition.CCo-8 putterin (co-sputtering)
Alternatively, it is desirable to form it by electron beam evaporation. Further, it is preferable to form the oxide by a CVD method using a desired metal halide.

In the present invention, it is desirable that the resistance value of the oxide be stabilized in advance by a treatment with electricity.

Next, an outline of the manufacturing method and form of the liquid jet recording apparatus manufactured in the examples or comparative examples of the present invention described in Sections 1 and subsequent sections will be explained.

First, heating resistor installed substrates corresponding to the following Examples and Comparative Examples were prepared 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 3 which also serves as the lower layer IO, selective etching is performed to form a layer with a width of 40 μm and a length of 200 μm, for example.
Heating resistors 11-1-11-3... were formed. In addition, the selective electrode 14 and the common electrode 1 are etched.
3 was formed. Furthermore, a protective layer (upper layer) 12 was laminated on the surface of each electrode and each heating resistor t, if necessary.

Apart from these, there is also a grooved plate formed by cutting a glass plate with a plurality of grooves (for example, width 40 μm x depth 40 μm) and a groove that will become a common ink chamber (not shown) using a micro-cutter. 4 was also created.

The heating resistor installed substrate and the grooved plate created in this way are bonded after aligning the heating resistor and the groove, and liquid ink is supplied from an ink supply unit (not shown) to the common ink chamber. 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 electrodes (common lead electrode 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 layer 12 includes: 1. OII layer thickness, Ta, 0.0.5
In the case where a thin layer of ti layer thickness was laminated on each heat generating resistor layer ll, a drive voltage margin of 1.5 to 1.9 times the foaming threshold voltage was obtained. This shows that heat resistance is further improved by providing the upper layer 12 compared to the case of a system in which the heat generating resistor layer 11 is exposed to the liquid.

At this time, the system without the upper layer 12 has a driving voltage margin of about 1.3 times the foaming threshold voltage, which is shown to be superior to the conventional system.

As the substrate 3, a silicon wafer was used in addition to the alumina substrate described above, and as the lower layer 10, a 2 to 5-μ Sin2 layer formed by thermally distributing the surface of the silicon wafer was used, and the same evaluation was carried out. was carried out, and similar good results were obtained.

Further, as the substrate 3, in addition to those used in the embodiments, glass, ceramics, heat-resistant plastic, etc. can also be used.

In addition to M, the electrode materials include Ant-Cu, A
1. -8i etc. can be used, but when using these materials, in order to isolate between the electrode and the liquid, remove the heat-active surface with a coating made of, for example, hardened photosensitive heat-resistant resin. It is preferable to cover the electrode and the area around the electrode.

Example A liquid jet recording apparatus having the configuration described above (sample AO
-1 to 3-3) (number of liquid channels: 128, -one electrothermal converter per liquid channel), when the -electrothermal converter was pulsed 5 x 1O8 times. Reliability was measured by counting the number of heat converters. The results are shown in the table below.

[Brief explanation of drawings]

The front partial view from the side, FIG. 1(b), is a partial cross-sectional view taken along the line XY in FIG. 1(a). ]...Liquid jet recording device, 2...Electrothermal converter, 3.
... Substrate, 4... Grooved plate, 5... Orifice, 6.
...Liquid discharge part, 7...Heat action part, 8...Heat generation part,
9... Heat action surface, lO... Lower layer, 11... Heat generating resistance layer, 12... Upper layer, 13... Common electrode, 14
...Selective electrode. Applicant Canon Co., Ltd.

Claims (1)

[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 the heating resistance layer constituting the electrothermal converter has In oxide as a main component; Cr, Mn, Fe, Co, Ni,
Cu, Zn, Ga, Zr, Nb. Mo, 几u, Pd, Cd, Sb, H
f, Ta, W, Au, Re. The liquid jet recording device according to claim 1, wherein the liquid jet recording device is formed of an oxide containing at least one element selected from the group consisting of Bi.