JPH028058A - liquid jet recording head - Google Patents

Abstract

PURPOSE:To facilitate high-density wiring and make it possible to omit a step and to achieve full-multiple orifice formation by providing an electro-thermal converter as a part of each of partition walls for defining liquid passages, and disposing discrete electrodes and a common electrodes to be connected to the converters on the side of a substrate and on the side opposite to the substrate. CONSTITUTION:A pair of heat generating resistors 5 provided for causing each of partition walls for defining liquid passages 4 to be entirely or patly an electro-thermal converter are erected oppositely to each other, on both sides of the liquid passage 4 in the vicinity of an orifice 3. Discrete electrodes 6 are provided on the upper side of a substrate 1, and are electrically connected respectively to the heat generating resistors 5, whereas a common electrode 7 is provided along the lower side of an orifice plate 2 in an area covering the heat generating resistors 5 provided respectively along the liquid passages 4 adjacent to each other. By this method it is possible to omit the step of providing the electro-thermal converters by a thin film forming technique. Since wiring can be simplified and, particularly, the discrete and common electrodes 6, 7 can be provided with sufficient widths, it is possible to restrict wiring resistance to a low value, and to restrain an electrical loss.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid jet recording head, and more particularly to a liquid jet recording head that performs recording by jetting recording liquid to form flying droplets.

[Prior Art] An inkjet recording device (liquid jet recording device) generates negligible noise during recording, is capable of high-speed recording, and uses a special process of fixing onto plain paper. Recently, there has been a lot of interest in the fact that recording can be done without the need for .

Among them, for example, Japanese Patent Application Laid-Open No. 54-518:17,
The liquid jet recording method described in DOLS No. 2843064 is different from other liquid jet recording methods in that it applies thermal energy to the liquid to obtain the driving force for ejecting droplets. , have different characteristics.

That is, in the recording method disclosed in the above-mentioned publication, the recording liquid subjected to the action of thermal energy undergoes a state change accompanied by a sharp increase in volume, and the acting force based on this state change causes the tip of the recording head to change. Recording is performed by ejecting liquid from the orifice, forming flying droplets, and making the droplets adhere to a recording member.

In particular, the liquid jet recording method disclosed in DOLS No. 284:1064 is a so-called drop-and-dem
Not only can it be applied extremely effectively to the AND recording method, but it can also be easily realized as a full 1ine type recording head with high density multi-orifices, making it possible to obtain high resolution and high quality images at high speed. It has the characteristic of being

By the way, one way to make the most of the features of such a high-density multi-nozzle recording head is to use a so-called fixed integrated full multi-head, which can record, for example, A4 size paper without scanning the recording head. One example is materialization.

Now, two examples of configurations of the heating resistor and electrodes in a conventional recording head used in the above recording method are shown in FIGS. 3A and 3B, respectively.

In these figures, 101 is a heating resistor, 102 is an individual electrode, and 103 is a common electrode.

Therefore, if we try to create a recording head with 16 nozzles per 1 mm on the same substrate with a width of 208 mm in the transverse direction of an A4 size sheet using such a configuration, the number of nozzles will be 208.
x16=3.328 trees, and the same number of heating resistors 101 and the same number of electrodes on both sides thereof are also required. In addition, in the conventional configuration, the electrodes 102 and 103 are obtained by forming conductor thin films in the same process, so for example, a 5,000-layer film of Al1 has a sheet resistance of 0.0.
If the electrode configuration is as shown in Figure 3A, the wiring resistance will be 1000 ohms when high-density wiring is performed as described above.
As a result, the electrical loss is extremely large.

Moreover, it requires advanced manufacturing technology to manufacture uniformly without defects over a width of 208 mm.

Furthermore, if the electrode configuration is as shown in FIG. 3B, the packaging density and wiring resistance can be reduced to half compared to those in FIG. If it is not made small, a potential gradient will occur. Since electrodes are formed using a thin film process, it is necessary to increase the area of the electrodes, but this is difficult due to the structure of the nozzle. The manufacturing method had issues such as limitations on film thickness and area, which resulted in high wiring resistance and high electrical loss.

[Problems to be Solved by the Invention] In other words, as mentioned above, in the conventional configuration, in order to achieve high-density multi-orifice, problems such as wiring resistance and potential gradient caused by the wiring form of the electrode must be solved. There are various challenges.

An object of the present invention is to solve the above-mentioned conventional problems, and to provide a liquid jet recording head that facilitates high-density wiring, can eliminate steps, and is suitable for full multi-orifice construction. be.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method in which a plurality of orifices are formed to selectively eject a recording liquid to generate flying droplets, and a plurality of orifices are formed, and a plurality of orifices are formed. Orifice plates are provided at opposing positions on the top, and electrothermal transducers that generate thermal energy for forming flying droplets are individually provided for each of the plurality of orifices. In a liquid jet recording head having a wave path that communicates with each other and is separated by a partition wall on a substrate, and a pair of electrodes connected to separate electrothermal converters, at least a portion of the opposing partition walls are electrothermal converted. Composed of the body,
It is characterized in that individual electrodes of the electrothermal converters and electrodes common to the plurality of electrothermal converters are respectively disposed on the substrate and on the surface of the orifice plate facing the substrate.

[Function] According to the present invention, at least a part of the partition wall forming the liquid path is used as an electrothermal converter, and the individual electrodes and the common electrode connected to the electrothermal converter are connected to the substrate side and the substrate side, respectively. By providing the electrode on the side facing the surface, not only can the wiring density of the electrode be distributed vertically across the liquid path, but also the process for configuring the conventional electrothermal converter can be omitted. This makes it possible to reduce manufacturing costs.

[Example] The present invention will be described below in detail and specifically based on the drawings.

FIG. 1 shows an embodiment of the invention. Here, 1 is a substrate made of an insulating material, 2 is an orifice plate also made of an insulating material, and 3 is an orifice bored in the orifice plate 2. In this way, the recording liquid guided to the liquid path 4 can be ejected from the orifice 3 in the form of flying droplets. Reference numeral 5 denotes a partition wall forming the liquid path 4 (here, the partition wall is shown by a broken line to make the explanation easier to understand) or a part thereof formed to serve as an electrothermal converter. In this example, a pair of heating resistors 5 are provided on both sides of the liquid path 4 as if facing each other.
is installed near the orifice 3.

6 is an individual electrode provided on the upper surface of the substrate 1 and electrically connected to the heating resistor 5 as shown in FIG. 2A;
On the other hand, a common electrode 7 is provided along the lower surface side of the orifice plate 2 between the heating resistors 5 and the earthen floor provided along the liquid paths 4 adjacent to each other.

Therefore, in the liquid jet recording head configured in this way,
By selectively supplying electrical signals to the individual electrodes 6,
The heating resistor 5 electrically connected to the individual electrodes 6 and the common electrode 7 generates heat, and the thermal energy acts on the recording liquid filling the liquid path 4, causing firing in the recording liquid. As a result, a 5'1N7 target droplet can be ejected from the orifice 3.

FIG. 2B shows another embodiment of the present invention, in which the individual electrode 6 is connected only to one side of the partition wall component, and the partition wall on the side to which the individual electrode 6 is connected only acts as an electrothermal converter.

[Effects of the Invention] As explained above, according to the present invention, at least a part of the partition wall forming the liquid path is used as an electrothermal converter, so that it is possible to At least the step of forming an electrothermal converter using a forming technique can be omitted, contributing to cost reduction. In addition, since it is not necessary to form all the electrodes closely together on the substrate as in the past, wiring can be simplified, and in particular, the common electrode can be formed with a sufficient width. It is possible to keep resistance low and suppress electrical loss.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an example of the configuration of a liquid jet recording head according to the present invention, FIG. 2A is a cross-sectional view taken along line A-A in FIG. 1, and FIG. 2B is a configuration of another embodiment of the present invention. FIGS. 3A and 3B are plan views schematically showing two examples of configurations of an electrothermal converter and its electrodes in a conventional liquid jet recording head. ...substrate, ...orifice plate, ...orifice, ...liquid path, ...heating resistor, ...individual electrode, ...-common electrode. 3 Orifice 2 angles, 1 line 1 line A-A wire surface drawing Figure 2A Figure 2B

Claims (1)

[Scope of Claims] 1) A plurality of orifices that selectively eject recording liquid to generate flying droplets, and an orifice plate in which the plurality of orifices are formed and provided at opposing positions on a substrate; An electrothermal converter that generates thermal energy for forming the flying droplets is separately provided corresponding to each of the plurality of orifices, communicates with each of the plurality of orifices, and is connected to a partition wall on the substrate. In a liquid jet recording head having separate liquid paths and a pair of electrodes connected to the individual electrothermal transducers, at least a portion of the opposing partition wall is constituted by the electrothermal transducer; A liquid jet recording head characterized in that individual electrodes of the electrothermal transducers and electrodes common to the plurality of electrothermal transducers are respectively disposed on the substrate and the surface of the orifice plate facing the substrate.