JPH0327387B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for manufacturing an inkjet head;
More particularly, the present invention relates to a method of manufacturing an inkjet head for generating recording ink droplets used in a so-called inkjet recording system.

An inkjet head applied to an inkjet recording system generally includes an ink passage having a fine ink ejection opening (orifice) and an ink ejection pressure generating element provided in a portion of the ink passage.

Conventionally, methods for creating such ink jet heads include, for example, molding plastic, cutting or etching a glass or metal plate to form fine grooves, and then forming these grooves. A method is known in which an ink passage is formed by joining a plate with another suitable plate.

However, in such a manufacturing method, when joining the plates, a fluid adhesive (for example, a thermosetting adhesive such as an epoxy resin, an unsaturated polyester, or a melamine resin, or a photosensitive adhesive) is used. Various problems have been pointed out due to the use of hardening type adhesives) or molten metals (alloys) such as solder. For example, 1. After the uncured adhesive flows into the groove, it hardens and blocks the ink passage, or after it adheres to the ink ejection pressure generating element, it hardens and deteriorates its intended function. There were problems such as deterioration of the performance of the obtained head.

2. In addition, in order to increase the manufacturing yield, a high degree of technical skill is required to set the amount of adhesive applied and to control the setting of curing conditions, and mass production is difficult.

3 Furthermore, when bonding is performed using eutectic alloys such as solder, it is possible to use the plating method, sputtering method,
It takes time and effort to form a film by vapor deposition, and there is also the problem that the alloy or metal used as the bonding agent may be altered or corroded by the ink, resulting in a loss of bonding strength.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for manufacturing a durable and reliable inkjet head that eliminates the above-mentioned problems.

Another object of the present invention is to provide a method for manufacturing a high-performance ink jet head in which ink passages are microfabricated with high precision and high yield.

The present invention achieves the above objects, and includes the steps of: providing an electrical/mechanical converter corresponding to the groove on a plate member having a groove for forming an ink passage; and above the electrical/mechanical converter. a step of providing a photosensitive resin film so as to cover the groove; an exposure step of exposing the photosensitive resin film in a pattern; removing an unnecessary portion of the photosensitive resin film according to the pattern; A method for manufacturing an ink jet head, comprising: a removing step of sandwiching an end of the electromechanical converter between the plate member and the photosensitive resin film.

Hereinafter, the present invention will be described in detail based on examples using drawings.

1 to 6 are explanatory diagrams of the first embodiment. In FIG. 1, photosensitive glass is etched to form shallow grooves 102 and through holes 103 as shown in the drawings, and the ink passage plate 101 is formed by etching the photosensitive glass. It is a schematic perspective view. FIG. 2 is a cross-sectional view of the ink passage plate 101 taken along line A-A'.

In this example, an ink passage plate made by etching photosensitive glass was used, but other methods such as etching of a metal plate, electroforming, photoforming,
Ink passage plates made from plastic molds can, of course, also be used in the present invention. It is also possible to transform this embodiment into a multi-array type head, in which case a plurality of shallow grooves 102 and through holes 103 similar to those shown in the figure may be provided.
They should be installed in parallel.

FIG. 3 shows the ink passage plate 101 shown in FIG.
A piezo element 104, which is an electrical/mechanical converter, is installed above the shallow groove 102. Although not shown here, an electrical signal input electrode is connected to the piezo element 104.

Next, as shown in FIG. 3, a sheet-like photosensitive resin 105 is placed on the top surface of the ink passage plate 101 equipped with the piezo element 104 at a temperature of 80 to 150°C and a pressure of 1 to 3 kg/kg.
Heat and press under ^cm2 conditions. (FIG. 4) Next, a predetermined pattern 106 is placed on the sheet-like photosensitive resin 105.
After the photomasks 106 having P are overlapped and aligned, exposure is performed. (Fig. 5) At this time, the pattern 106P is the piezo element 1
It has a planar shape that is almost similar to the planar shape of 04 and is slightly smaller.

When exposed as described above, the outside of the pattern 106P area, that is, the exposed photosensitive resin 105 undergoes a polymerization reaction and is cured, becoming insoluble in solvents. On the other hand, the photosensitive resin 105 that has not been exposed to light is not cured and remains soluble in the solvent.

After going through the exposure operation, volatile organic solvents, e.g.
When the unpolymerized (uncured) photosensitive resin 105 is dissolved and removed by immersion in trichloroethane, the cured resin film 105H is fixed on the upper surface of the ink passage plate 101, sandwiching the ends of the piezo elements 104. (FIG. 6) After that, the cured film 10 of the sheet-like photosensitive resin
In order to further improve the solvent resistance (ink resistance) and mechanical strength of 5H, thermal polymerization (60~
Heat for 180 minutes) or irradiate with ultraviolet light (e.g. 50~
irradiation at 200 mw/ ^cm2 for 3 to 60 seconds).

It is also a good method to use both of these in combination to improve the properties such as the ink resistance and mechanical strength.

FIG. 6 is a perspective view of the appearance of the ink jet head obtained in this manner.

Thereafter, an ink supply pipe (not shown) is connected to the through hole 103 to complete the ink jet head.

The head face can also be cut along line B-B' in FIG. 6, if necessary. This is the ink ejection port 1 of the piezo element 104.
This is an impossible process to optimize the distance to 07,
For this cutting, a dicing method commonly employed in the semiconductor industry can be applied, and if necessary, the cut surface is polished to make it smooth.

Here, other embodiments will be explained using FIGS. 7 to 13.

FIG. 7 is a schematic perspective view of the ink passage plate 201 formed by etching photosensitive glass to form shallow grooves 202a and 202b of different sizes as shown and communication grooves 202c and 202d between them.

FIG. 8 is a cross-sectional view of the ink passage plate 201 taken along line CC'.

In this example, an ink passage plate made by etching photosensitive glass was used, but other methods include etching metal plates, electroforming, photoforming, and plastic molding. Of course, an ink passage plate made by the method can also be used.

It is also possible to use an ink passage plate in which a photosensitive resin film is pressure-bonded onto a suitable flat plate and then grooves are formed using a cured resin film by photolithography.

Further, this embodiment can also be modified to a multi-array type head, in which case a plurality of grooves similar to those shown in the drawings may be arranged in parallel.

FIG. 9 shows the ink passage plate 201 shown in FIG.
A piezo element 204, which is an electrical/mechanical converter, is installed above the shallow groove 202a. Although not shown here, an electrical signal input electrode is connected to the piezo element 204.

Next, as shown in FIG. 9, a sheet-like photosensitive resin 205 is placed on the top surface of the ink passage plate 201 equipped with the piezo element 204 at a temperature of 80 to 150°C and a pressure of 1 to 3 kg/kg.
Heat and press under ^cm2 conditions. (FIG. 10) Next, a predetermined pattern 20 is placed on the sheet-like photosensitive resin 205.
Photomask 206 with 6P ₁ and 206P ₂
After overlapping and positioning, exposure is performed. (Fig. 11) At this time, pattern 206P ₁
has a planar shape that is substantially similar to the planar shape of the piezo element 204 and is slightly smaller.

Further, the pattern _206P2 is for forming a communication port with an ink supply pipe in the sheet-like photosensitive resin 205 later.

When exposed as described above, the outside of the pattern area, that is, the exposed photosensitive resin 205 undergoes a polymerization reaction and hardens, becoming insoluble in solvents. On the other hand, the photosensitive resin 205 that has not been exposed to light is not cured and remains soluble in the solvent.

After going through the exposure operation, volatile organic solvents, e.g.
When the unpolymerized (uncured) photosensitive resin 205 is dissolved and removed by immersion in trichloroethane, the cured resin film 205H is fixed on the upper surface of the ink passage plate 201 with the piezo element 204 sandwiched therebetween. (FIG. 12) Incidentally, in FIG. 12, 203 is a through hole formed in the cured resin film 205H, to which an ink supply pipe (not shown) is connected.

After that, the cured film 20 of the sheet-like photosensitive resin is
In order to further improve the solvent resistance (ink resistance) and mechanical strength of 5H, thermal polymerization (60~
180 minutes) or UV irradiation (e.g.
(irradiation at 50-200 mw/ ^cm2 for 3-60 seconds).
It is also a good method to use both of these in combination to improve the properties such as the ink resistance and mechanical strength.

After that, the ink supply pipe 20 is inserted into the through hole 203.
8 to complete the inkjet head. (FIG. 13) If necessary, the head face surface can also be cut along line DD' in FIG. 12. This is the piezo element 204 and the ink ejection port 2.
This is an additional process to optimize the distance from 07.
For this cutting, a dicing method commonly employed in the semiconductor industry can be applied, and if necessary, the cut surface is polished to make it smooth.

In addition, as the sheet-like photosensitive resin shown in the examples, what is generally called a dry film photoresist is recommended, such as DuPont's permanent photopolymer coating RISTON,
Solder mask 730S, 740S, 730
Photosensitive resin films such as FR, 740FR, and SMI, which are commercially available from Hitachi Chemical under the trade name of Fotec, can be used.

The effects of the present invention explained in detail above include:
It can be enumerated as follows.

1. Since the ink jet head is manufactured without using adhesive at all, the adhesive will not flow and block the ink passage or adhere to the ink ejection pressure generating element and cause functional deterioration.

2.Although the use of liquid adhesive requires great skill, the manufacturing method of the inkjet head of the present invention is simple and reliable, and allows for continuous and mass production.

3. Since the bonding area can be limited by photolithography, it is possible to manufacture ink jet heads with high precision and accuracy. According to the present invention, an electrical/mechanical converter is first held down by a photosensitive resin film, and unnecessary parts thereof can be removed in that state by utilizing the photosensitivity of the photosensitive resin film. Therefore, the pressing force of the photosensitive resin film is strong, and this pressing process does not require very strict positioning accuracy, and unnecessary parts of the photosensitive resin film can be removed easily and easily using exposure. It can be performed with high precision. In addition, in the inkjet head manufactured according to the present invention, by removing unnecessary parts, it is possible to create a structure in which the end part of the electromechanical converter is located between the plate member and the photosensitive resin film. Because you can take
The amount of displacement of the central portion (displacement portion) of the electrical/mechanical converter can be maximized effectively.

4. Production efficiency is good because there are relatively few manufacturing steps.

5. Since so-called printing technology can be used in the main process of manufacturing the head, it is easy to manufacture multi-array type inkjet heads.

[Brief explanation of drawings]

1 to 6 are explanatory diagrams of one embodiment of the present invention, and FIGS. 7 to 13 are explanatory diagrams of other embodiments. In the figure, 101 and 201 are ink passage plates, 1
02, 202a, 202b, 202c, 202d
is a groove, 103, 203 is a through hole, 104, 204
1 is a piezo element, 105H and 205H are cured resin films, 107 and 207 are ink discharge ports, and 208 is an ink supply pipe.

Claims (1)

[Scope of Claims] 1. A step of providing an electric/mechanical converter corresponding to the groove on a plate member having a groove for forming an ink passage, and forming the groove on the electric/mechanical converter. a step of providing a photosensitive resin film so as to cover the plate member; an exposure step of exposing the photosensitive resin film in a pattern; and removing an unnecessary portion of the photosensitive resin film according to the pattern to form the plate member. and a removing step of sandwiching the end of the electromechanical converter between the photosensitive resin film and the photosensitive resin film. 2. The ink jet head according to claim 1, wherein in the removing step, unnecessary parts of the photosensitive resin film are removed and holes for supplying ink to the ink passage are created in the photosensitive resin film. manufacturing method.