JPS6317627B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method of making a liquid jet recording head. The non-impact recording method has recently attracted attention because the noise generated during recording is so small that it can be ignored. Among these, the liquid jet recording method, in other words, the inkjet recording method, is recognized as an extremely powerful recording method that allows high-speed recording and can record on plain paper without the need for special fixing treatment. ing. Various methods have been proposed for this inkjet recording method, some have been improved and commercialized, and others are still being worked on to put them into practical use. be. The inkjet recording method is basically a method in which droplets of a recording liquid called ink are ejected.
Recording is performed by attaching it to a recording member. The inkjet recording method is roughly divided into several methods based on the method of generating droplets of the recording liquid and the control method for controlling the flying direction of the generated recording liquid. Typical examples of these are shown below. One of them is the so-called (Teletype method) disclosed in USP 3060429, which generates a liquid flow using electrostatic attraction and attaches the generated liquid flow directly onto the recording member as necessary. In this method, recording is performed by causing the droplets to adhere to the recording member by controlling the flying direction with an electric field. The second method is a method disclosed in USP3596275 (Sweet method), USP3298030 (Lewis and Brown method), etc., and uses a continuous vibration generation method to generate a droplet flow with a controlled amount of charge. ,
Recording is performed on a recording member by causing the generated flow of droplets with a controlled amount of charge to fly between deflection electrodes to which a uniform electric field is applied. The third method is the so-called (Hertz method) disclosed, for example, in USP 3416153, in which an electric field is applied between a nozzle and a ring-shaped charged electrode, and droplets are generated by a continuous vibration generation method. This is a method of converting and recording. In this method, the atomization state of the droplets is controlled by modulating the electric field strength applied between the nozzle and the charging electrode in accordance with the recording signal, and the gradation of the recorded image is produced. The fourth method is, for example, the method disclosed in USP 3,747,120 (Stemme method), and this method is fundamentally different in principle from the above three methods. In other words,
(Stemme method) applies an electrical recording signal to a piezo vibrating element attached to a recording head that has an orifice that ejects liquid for recording, and then transmits this electrical recording signal to the mechanical vibration of the piezo vibrating element. Instead of vibration, recording is performed by ejecting droplets from the orifice and adhering them to the recording member whenever necessary according to the mechanical vibration. Separately, a new recording method that is different in principle and idea from the first to fourth methods was also proposed in the applicant's earlier application (that is, Japanese Patent Application No. 118798-1982). There is. In short, this new method applies a thermal pulse as an information signal to the recording liquid introduced into the liquid path, and the liquid changes its state according to the acting force. This is a method in which the liquid is ejected and made to fly as small droplets from an orifice attached to a liquid path, and the liquid is attached to a recording member to perform recording. By the way, with respect to the various liquid jet recording methods exemplified above, there still remain technical problems common to all of them that must be solved. One is to develop a method for creating a recording head with a multi-array of liquid ejection orifices in order to speed up such printing.The second is to make the particle size of ejected droplets uniform. The purpose of this invention is to develop a method for producing a recording head equipped with a multi-array orifice, each of which has a uniform opening diameter, in order to improve the recording quality. However, it is not easy to satisfy these conditions required for such a recording head from the standpoint of manufacturing. For example, originally one nozzle part was made up of fine pores, and in order to complete a multi-array recording head by combining multiple pores, it required a high level of technical skill because the pores were extremely minute. It takes. Since each of its constituent elements is required to be homogeneous, it is not easy to manufacture it with a good yield. As described above, when forming a multi-array of recording heads in which each component itself is minute and precise, further technical difficulties arise. In view of such circumstances, the present invention proposes a method for producing a liquid jet recording head that satisfies the problems listed in the above sections and sections, in other words,
The main object of the present invention is to provide a liquid jet recording head that has a simple configuration and enables high-speed, high-quality recording. Another object of the present invention is to provide a liquid jet recording head that can be manufactured easily and with high precision. Therefore, the gist of the present invention that can achieve these objects is to include a first member that forms a space area that is to become a liquid path, and a separate second member that covers the space area. A method for producing a liquid jet recording head formed by joining two members to each other, the method comprising: providing an electric/heat exchanger at one of the joining parts of the first member and the second member; A method of manufacturing a liquid jet recording head is characterized in that the two members are joined to each other by causing a joining action at the joining site by the heat generating action of the electricity/heat exchanger. Hereinafter, the present invention will be explained in detail with reference to illustrated examples. First, the present invention will be explained in detail with reference to a procedure for producing a multi-array recording head. As shown in FIG. 1, a plurality of long grooves 1 ₁ , which will later become liquid paths in the liquid jet recording head,
A flat plate 2 as a first member made of a material such as glass, quartz, ceramic, plastic, metal, alloy, etc., on which 1 ₂ , 1 ₃ , 1 ₄ , 1 ₅ , and 1 ₆ are engraved is prepared. Separately, a second
A flat plate 3 as a member is also prepared. The flat plate 3 shown in the second figure is also made of the same material as the flat plate 2. In this second illustrated example, 4 ₁ , 4 ₂ , 4
₃ , 4 ₄ , 4 ₅ , 4 ₆ , and 4 ₇ are all electricity/heat exchangers formed on the flat plate 3 in patterns corresponding to predetermined joint locations. Each of these converters includes an individual electrode 5 and a common electrode 6, and generates heat by passing current between these electrodes. (In addition,
The converter used for this joining can also be provided on the flat plate 2. ) These conversion bodies can be created, for example, as follows. That is, in advance, as a heat storage layer on the flat plate 3,
SiO ₂ is deposited on top of it as a heating resistor layer.
Ta ₂ N is deposited and then aluminum is deposited as an electrode. A desired pattern is formed on this aluminum electrode by etching or the like. At the same time, at least a region of the heating resistor layer corresponding to the predetermined bonding site is exposed. In the manner described above, an electrical/heat exchanger, a so-called thermal head, is formed. Incidentally, the above-mentioned patent application for the recording head of the present invention
When adapting to the liquid jet recording method shown in No. 52-118798, the electric/heat exchanger portions 7 ₁ , 7 ₂ , 7 ₃ , 7 for inputting recording signals may be added simultaneously with the above-mentioned steps or as a separate step. ₄ , 7 ₅ , 7 ₆ , are also formed.
The exposed surface of the electric/heat exchanger for inputting recording signals is further coated with a protective layer such as SiO ₂
It is desirable to vapor-deposit etc. Electricity/heat exchanger 7 for inputting the recording signal mentioned above
₁ , 7 ₂ , 7 ₃ , 7 ₄ , 7 ₅ , and 7 ₆ are flat plates that constitute the main part of the present invention and constitute energy application parts for ejecting the recording liquid in the liquid chamber as small droplets from the orifice. Electricity/heat exchangers 4 ₁ , 4 ₂ , 4 3 , 4 ₄ , _{4 5} , 4 used to join 2 and the flat plate 3
₆ and ₄₇ have different functions, and the electricity/heat exchanger serving as the energy acting portion can be replaced with a conventionally known piezo vibrating element. In addition, in the present invention, regardless of whether the energy acting part is an electric/heat exchanger or a piezo vibrating element, a space area that is to become a liquid chamber is formed in the flat plate 2 as the first member. In order to form the long grooves 1 ₁ ... 1 ₆ shown in FIG. It is also possible to integrally mold the Next, as shown in the first diagram, the groove bank portions 1a, 1 of the flat plate 2
b, 1c, 1d, 1e, 1f, 1g are the second
Illustrated electrical/heat exchanger attachment parts 4 ₁ , 4 ₂ , 4 ₃ , 4
₄ , ₄₅ , ₄₆ , and ₄₇ , the flat plates 2 and 3 are overlapped. This state is taken as a cut plane along the broken lines X and X' in Figures 1 and 2.
FIG. 3 shows a schematic cross-sectional view. At this time, any of the groove bank portions 1a...1g and the converter attachment portions ₄₁ ... ₄₇ are coated with a heat-sensitive adhesive. The bonding agent used here is a material that produces a bonding effect when heated, and includes organic compounds such as epoxy resin adhesives, phenol resin adhesives, urethane resin adhesives, and silicone resin adhesives. adhesives, molten silver salts described in Japanese Patent Publication No. 38-20227,
These are inorganic compounds such as low-melting glasses. Among these, the latter inorganic compounds are often used in the form of powder rather than liquid. Further, in the present invention, such a bonding agent may not be particularly used. For example, when the materials of the flat plates 2 and 3 have the property of melting under the action of heat, they can be joined by fusing themselves. In this way, materials that can be fused and bonded without requiring a separate bonding agent include inorganic compounds such as glass, low melting point metals, polyethylene, polypropylene, ABS resin,
Thermoplastic resins such as polycarbonate and polymethyl methacrylate can be mentioned. Of course, it is also possible to use a combination of these organic and inorganic materials. After the flat plate 2 and the flat plate 3 are stacked on top of each other as shown in the third figure, electricity is applied to the electricity/heat exchangers 4 _{1 .} . . 4 ₇ provided in advance on the flat plate 3 to generate heat. The heat generated here joins the flat plates 2 and 3 at their abutting portions. At this time, it is extremely easy to generate enough heat for the above bonding in the converters 4 ₁ ... 4 ₇ , and generally a so-called thermal head, which is commonly used in the field of heat-sensitive recording, is used. You can do this by In addition, since these converters 4 ₁ ... 4 ₇ are used only once in the bonding process (in other words, there is no need to reuse them), a large amount of heat is required to the extent that they are damaged. As a result, thermal bonding can be performed with sufficient strength and precision for practical use. According to the joining technology described in detail above, it is a method that achieves joining by effectively concentrating heating only on the desired joining location, rather than heating the entire part to be joined, so that the finished product is not heated. No unnecessary thermal deformation remains. This allows obtaining a fine structure (for example, as shown in the third figure, the cross-sectional opening size of the long groove is usually about 5 μm x 5 μm to 250 μm x 250 μm) and precise structure as in the present invention. If so, that's a big advantage. In addition, the bonding agent used in the above-mentioned bonding technology is
It may flow into the elongated groove and harden there, clogging it, staining the surface of the signal input converter 7 ₁ ... 7 ₆ , or causing the flat plate or other structural members themselves to melt and become elongated. It has the advantage that problems such as deformation of the groove or sealing do not occur. Furthermore, in the above-described bonding process, if the electricity is applied to an extent that the electricity/heat exchanger is not damaged, the liquid jet recording head according to the present invention made by bonding the flat plates 2 and 3 can be used even after they are bonded. Since fusion bonding can be performed by energizing the electric/heat exchanger, re-fusion bonding and bonding reinforcement can be performed as necessary after the liquid jet recording head is completed. Therefore, the resulting head is precise and has almost no structural defects. The method for producing a recording head according to the present invention will be explained in more detail with reference to examples. Example 1

[Table] A member as shown in the second diagram was prepared using the indicated constituent members. In other words, the heating elements 4 ₁ ... 4 ₇ for bonding are each placed on an alumina substrate with a size of 100 μm x 5 mm.
Similarly, the signal input heating elements 7 ₁ ... 7 ₆ are patterned at 100 μm intervals, respectively.
A pattern with a size of 100 μm was formed. Apart from this, the thickness of the grooved plate shown in the first illustration is
It was made from a 1.3mm glass plate. In addition, each groove was created using a diamond cutter with an interval of 100 μm.
A groove with a width of 100 μm and a depth of 100 μm was formed by cutting. Next, a bonding agent having the following composition was applied to the grooved surface to a thickness of approximately 3 μm. Bonding agent composition Epicoat #828 Epoxy resin manufactured by Ciel Sekiyu Co., Ltd. 100 parts by weight Epomate B-002 Epoxy resin curing agent manufactured by Ajinomoto Co., Inc. 30 parts by weight Next, after overlapping both of the above members as shown in the third figure, So that the heating element surface temperature is approximately 150℃.
Electricity was applied to the joining heating elements ₄₁ ... ₄₇ . After the bonding effect has been sufficiently observed, the electricity is turned off, the whole is transferred to a methanol solution, and ultrasonic cleaning is performed. Uncured bonding agent, etc. are removed and the multi-array inkjet head is free from clogging. Created. Example 2 First, a grooved plate as shown in Figure 1 was prepared by cutting grooves with a width of 50 μm and a depth of 50 μm at a pitch of 100 μm on a soft glass plate (thickness: 1 mm) using a diamond cutter. Separately, a heating element attachment member similar to that in Example 1 (however, the heating element attachment interval was 50 μm) was prepared. Next, after aligning the two, a current was applied to the heating element for bonding so that the surface temperature of the heating element reached 800°C, and the two were bonded. A multi-array inkjet head with a liquid path of a predetermined size was obtained. It was done. It should be noted that no clogging or deformation of the liquid path was observed in this head. Using the thus obtained head of the present invention, liquid jet recording as shown in the fourth example shown below can be performed as an example. In order to simplify the explanation, FIG. 4 shows a recording device using a single orifice head. In other words, in this illustrated example, the recording liquid 4 introduced into the liquid path 9 from the introduction pipe 8 (sometimes abbreviated as ink) 10 indicates the energization of the signal input heating element 11 attached to the liquid path 9. The state changes instantaneously in response to heat generation. The heating element 11 generates a thermal pulse as an information signal by applying electricity through electrodes 12 ₁ and 12 ₂ connected thereto. Due to the change in state, an acting force is applied to the liquid 10, and as a result, the liquid 10 is efficiently ejected and flies as small droplets 14 from the orifice 13 provided in communication with the liquid path 9, and the liquid 10 is ejected and flies onto the recording member. Recording is done by depositing on 17. The heating element 11 is provided on the substrate 15, and the voltage of the power source 16 is applied according to the recording input, the heating element 11 generates heat according to the input signal, and recording according to the input signal is performed on the recording member 17. It is formed by small droplets 14 that fly and adhere to the surface. The diameter of the orifice 13 is approximately 40 μφ. Although this illustrated example shows a single orifice recording device for convenience of explanation, it is of course possible to transform this into a multi-array (orifice) recording device (not shown). Furthermore, the recording method is not limited to that shown in the illustrated example.

[Brief explanation of the drawing]

1 and 2 are schematic perspective views for explaining the main elements constituting a recording head to which the present invention is preferably applied, and FIG. 3 is a schematic perspective view of the recording head shown in FIGS. FIG. 3 is a cross-sectional view taken along the dotted line X and X', illustrating a state in which each element is superimposed. or,
FIG. 4 is a schematic perspective view of a liquid jet recording apparatus illustrating one recording method using a recording head using the manufacturing method of the present invention. In the figure, 1 ₁ , 1 ₂ , 1 ₃ , 1 ₄ , 1 ₅ , 1 ₆ ...
Long groove, 1a, 1b, 1c, 1d, 1e, 1f,
1g... Bank part, 2, 3... Flat plate, 4 ₁ , 4 ₂ , 4
₃ , 4 ₄ , 4 ₅ , 4 ₆ , 4 ₇ ... heating element for joining, 5 ...
Individual electrode, 6... Common electrode, 7 ₁ , 7 ₂ , 7 ₃ , 7
₄ , 7 ₅ , 7 ₆ , 11, ... Heating element for signal input, 9
. . . Liquid path, 13 . . . Liquid discharge orifice.

Claims (1)

[Claims] 1. A method for producing a liquid jet recording head formed by joining together a first member forming a spatial region to become a liquid path and a second member separate from this for covering the spatial region. At that time, electricity is applied to one of the joining parts of the first member and the second member.
A method for producing a liquid jet recording head, characterized in that a heat exchanger is provided, and the two members are joined to each other by producing a joining action at the other joining part by the heat generating action of the electricity/heat exchanger.