JPH05261932A - Manufacture of ink jet head - Google Patents

Abstract

PURPOSE:To manufacture an ink jet head with stable ink jetting characteristics by a method wherein dripping of an adhesive into a passage groove is prevented from happening to form the shape of the passage groove of high precision. CONSTITUTION:After a filling material (naphthalene) 5 under a molten condition is injected in a passage groove (1a) which is formed on a passage substrate 1, the filling material is cured to close the passage groove (1a). Then, a lid plate 2, on which a piezoelectric element 4 and adhesive 3 are provided, is press-bonded to the passage substrate 1, and the passage substrate 1 and lid plate 2 are joined by curing the adhesive 3 under this condition. Then, the filling material 5 is heated to melt, and removed from the passage groove (1a).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an ink jet head for joining a flow path substrate and a cover plate.

[0002]

2. Description of the Related Art Conventionally, some ink jet heads have a flow path substrate in which flow path grooves through which ink flows are formed, and a lid plate joined to the flow path substrate. In order to manufacture such an inkjet head, the following method is usually adopted.

First, a flow path substrate having a desired flow path groove is formed by resin molding or etching a photosensitive material. Next, apply adhesive to one side of the lid plate,
An adhesive layer having a thickness of about m to several tens of μm is formed. Then, the flow path substrate and the cover plate are overlapped with each other so that the adhesive layer faces the flow path groove forming surface, and the adhesive is hardened in a state of being sufficiently pressed so that the two are in close contact with each other without a gap. In this way, the flow path substrate and the cover plate are joined together to form an inkjet head. As the adhesive, various adhesives such as a heat-adhesive adhesive, a pressure adhesive adhesive, a cooling adhesive adhesive, an anaerobic adhesive adhesive, and an ultraviolet curable adhesive are used.

[0004]

According to the above-mentioned prior art, when the cover plate coated with the adhesive is bonded to the flow path substrate while applying pressure, the adhesive on the bonding surface drips into the flow path groove,
In the worst case, it blocks the flow channel. Therefore, the shape of the flow channel cannot be accurately formed, and the ejection of ink becomes unstable.

As a means for removing the dripping, it is possible to dissolve and wash away the drooping adhesive with a solvent, but if the adhesive completely blocks the flow channel, the solvent cannot flow. Even if the flow channel is not completely closed, if the flow channel substrate is formed by molding and has a warp, the adhesive will fill the gap between the flow channel substrate and the cover plate due to the warp. It is filled, and even this portion will be dissolved by the solvent. Then, the adhesion between the flow path substrate and the cover plate deteriorates, and the injection characteristics also deteriorate. As described above, it is difficult to effectively prevent the adhesive from dripping into the flow channel.

Therefore, an object of the present invention is to provide a method for manufacturing an ink jet head having a stable ink ejection characteristic by preventing the adhesive from dripping into the flow channel and accurately forming the shape of the flow channel. Especially.

[0007]

In order to achieve the above object, a method for manufacturing an ink jet head according to the present invention comprises:
The method is characterized in that the filling material is filled in the flow passage groove formed in the flow passage substrate, then the lid plate is adhered to the flow passage groove forming surface of the flow passage substrate, and then the filling material is removed. Is.

The step of removing the filler can be carried out by heating and melting the filler.

Alternatively, it is possible to carry out the removal by holding the filler made of an aqueous liquid in the flow channel groove in a frozen state and heating and thawing in the removing step.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a method of manufacturing an ink jet head as shown in FIG. 1, one example of which is shown in FIGS. First, as shown in FIG. 2, a flow path substrate 1 having a flow path groove 1a of a desired shape is formed by injection molding of plastic, and the flow path substrate 1
And the lid plate 2 to be adhered are formed. The cover plate 2 is coated with an anaerobic adhesive 3 on one surface to form an adhesive layer having a thickness of several μm to several tens of μm, and on the other surface via a conductive pattern (not shown). Piezoelectric element 4 to which power is supplied
Ink ejection means such as is provided.

Next, as shown in FIG. 3, a filling material 5 is filled so as to close the flow channel 1a of the flow channel substrate 1. In this embodiment, a material containing naphthalene as a main component is used as the filler 5. Since the melting point of naphthalene is 80.5 ° C,
Naphthalene is injected into the flow path groove 1a in a state of being heated to a higher temperature (for example, 90 ° C.) and melted, and then cooled to room temperature to solidify the naphthalene.

Subsequently, as shown in FIG. 4, the surface of the flow path substrate 1 filled with the filling material 5 and the adhesive 3 of the lid plate 2 are opposed to each other, and they are sufficiently applied so as to be closely adhered to each other without a gap. The adhesive 3 is cured under pressure. In this way, the bonding is completed in a state where the size and the shape of the flow channel 1a are accurately secured by the filling material 5. The surface 5a of the filling material 5 has sufficient hardness to withstand the pressure applied at the time of bonding, and the shape of the flow channel 1a is determined by the filling state of the filling material 5.
Is slightly raised, the ink flow path becomes larger accordingly. The surface 5a of the filling 5 as shown in FIG.
By making the flat with respect to the flow path substrate 1, it is possible to secure the shape according to the design value.

Finally, the flow path substrate 1 and the cover plate 2 are reheated to melt and remove the filling material (naphthalene) 5 and thoroughly washed to obtain an accurate flow as shown in FIGS. The inkjet head with the road shape maintained is completed.

According to the method described above, since the accurate flow path shape is secured and the adhesive 3 does not drip into the flow path groove, an ink jet head having desired ejection characteristics can be manufactured accurately and stably. ..

In the above embodiment, the adhesive 3 is applied to the cover plate 2.
Was applied to the joint surface of the flow path groove 1a as shown in FIG.
The adhesive 6 may be applied to the joint surface of the flow path substrate 1 with the filler 5 being filled therein.

Before the filling material 5 is dissolved, polishing or the like may be performed to flatten the nozzle portion at the tip of the flow path. Further, as shown in FIG. 7, the flow path substrate 7 is formed in a large size,
The channel groove tip portion 7a is formed so as to be located deeper than the end surface of the substrate 7, the filling material 5 is filled, the lid plate is adhered, and then cut along the cutting line 8 at the channel groove tip. You may do it. As shown in FIG. 8, the liquid filler 11 is injected in a state where the seal plate 10 is fixed to the end face of the flow channel substrate 9 and the flow channel groove tip 9a is sealed, and the seal plate 1 is cured after the filler is cured.
You may remove 0.

As shown in FIG. 9, the substance 12 having the property of repelling the filler is formed in advance on the end portion of the flow channel 13a of the flow channel substrate 13 by coating or coating, and the adhesive portion (other than the flow channel groove) is formed. The portion 14b) may be prevented from invading the filling material 14.

Although the naphthalene compound is used as the filler and the anaerobic adhesive is used as the adhesive in the above embodiments, the present invention is not limited to this. For example, acetic acid (melting point: 16.6 ° C.), polyvinyl alcohol (gel at the time of cooling, and sol at the temperature of 80 to 90 ° C.) can be used as the filler. Further, it is also possible to inject water into the channel groove to freeze it and use ice as a filler. As the adhesive, various types of adhesives such as pressure-curing type, heat-curing type, cooling-curing type, and UV-curing type can be specified. In this case, an adhesive is selected according to the properties of the filler. For example, water as a filling,
When an aqueous liquid such as ink is used and a non-heating type adhesive such as a cooling type or an ultraviolet curing type is used, cooling and freezing
It is possible to carry out a construction method in which filling is carried out, adhesion is cured, and then the composition is removed by heating and thawing. According to this, there is an advantage that filling and removal are easy and the head material is not affected.

[0019]

According to the present invention, since a flow channel having a precise size and shape can be obtained without narrowing or filling of the flow channel due to dripping of an adhesive, an ink jet head having desired ink ejection characteristics can be obtained. It can be manufactured stably.

[Brief description of drawings]

FIG. 1 is a developed perspective view of an inkjet head manufactured according to the present invention.

FIG. 2 is a partially enlarged sectional view showing a first step of the first embodiment of the present invention.

FIG. 3 is a partially enlarged sectional view showing a second step.

FIG. 4 is a partially enlarged sectional view showing a third step.

FIG. 5 is a partially enlarged sectional view of the inkjet head in a completed state.

FIG. 6 is a partially enlarged cross-sectional view showing a second embodiment.

FIG. 7 is an exploded perspective view showing a third embodiment.

FIG. 8 is an exploded perspective view showing a fourth embodiment.

FIG. 9 is a partially enlarged sectional view showing a fifth embodiment.

[Explanation of symbols]

 1,7,9,13 Channel substrate 1a, 7a, 9a, 13a Channel groove 2 Cover plate 3,6 Adhesive 5,11,14 Filling material

Claims (3)

[Claims] 1. A step of filling a flow path groove formed in a flow path substrate with a filling material, and a step of adhering a lid plate to the flow path groove forming surface of the flow path substrate after the filling step, And a step of removing the filler after the bonding step. 2. The filling material removing step is performed by heating and melting the filling material.
The method for manufacturing an inkjet head according to item 1. 3. The ink jet head manufacturing method according to claim 1, wherein the filling material is an aqueous liquid and is held in a frozen state in the flow path groove, and the removing step is performed by thawing by heating. Method.