JP2001071511A - Method for forming liquid chamber in ink jet printer head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute heat-bonding of substrates in a short time in the case where a substrate laminated body for forming a liquid chamber of an ink jet printer head is produced. SOLUTION: A layer of an adhesive that represents and adhesive force by heating is interposed between substrates and the adhesive layer is heated by a lamp light source and then the substrates are bonded to form a substrate laminated body. When the silicon substrate 1, 3 are bonded with each other, a thermoplastic polyimide series adhesive 2 (organic solvent) is coated on the surface of the substrate 1 to be bonded and leveling, preliminary drying and making of film is applied to the adhesive 2. The substrate 1 is loaded on a support member 7 of quartz and the substrate 3 is aligned to be loaded in contact with the substrate 1. While these substrates 1, 3 are pressed by a pressing plate 8, the adhesive 2 (together with the substrates) is concentratively heated by a halogen lamp 4a, thereby achieving the bonding of the substrates 1, 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a substrate laminate formed by joining and laminating a plurality of substrates for forming a liquid chamber of an ink-jet printer head. It is about.

[0002]

2. Description of the Related Art Conventionally, when a substrate laminate for forming a liquid chamber of an ink jet printer head is obtained, a method of bonding substrates by bonding is to laminate an adhesive film or apply an adhesive. In general, a method of superimposing a substrate on a substrate to be joined and thermocompression bonding is adopted.

In recent years, as the resolution of an ink jet printer has been increased, the structure of members constituting the ink jet printer head has been miniaturized. Therefore, high precision alignment is required for thermocompression bonding. In this thermocompression bonding method, the substrate is aligned with a pressing jig and installed, and then this pressing jig is put into a heating furnace. There is a method of pressing (pressing) the substrate.

[0004]

However, in the former thermocompression bonding method, it takes time for the pressing jig to reach a desired temperature, and particularly when the desired temperature is high (for example, 200 ° C. or higher). As the process time increases, there is a problem that the increase in the processing time cannot be ignored as a process cost.

In the latter thermocompression bonding method, it takes time for the heater to reach a desired temperature. In addition, when the stage is set to a desired temperature in advance, a problem has occurred depending on the alignment method. Also, as described above, since high-precision alignment is required before the substrate is pressed, when a CCD camera is used, camera shake and image fluctuation due to heat hinder the alignment, There is also a problem that the life of the camera is shortened.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has as its object to produce a substrate laminate for forming a liquid chamber of an ink jet printer head by bonding substrates, and to heat the substrate at the time of substrate bonding with a lamp. By performing the heating, only the substrate and the adhesive are efficiently heated (selective concentrated heating of the substrate and the adhesive), thereby realizing the heat bonding between the substrates in a short time.

[0007]

According to a first aspect of the present invention, there is provided a method for manufacturing a liquid chamber of an ink jet printer head, comprising the steps of: forming a liquid chamber of an ink jet printer head by using a substrate laminate formed by bonding and laminating a plurality of substrates; A substrate laminate is obtained by interposing an adhesive layer exhibiting adhesive force by heating between substrates to be bonded, heating the adhesive layer with a lamp light source, and joining the substrates to each other.

In the liquid chamber manufacturing method of the first aspect, the method of interposing the adhesive layer between the substrates to be joined includes: (1) interposing only the adhesive layer between the substrates; (2) An adhesive film having the above-described adhesive layer formed on both surfaces thereof (for example, a laminate film obtained by laminating a thermoplastic resin-based adhesive on both surfaces of a plastic film substrate) is provided between substrates.

A liquid chamber manufacturing method according to a second aspect is characterized in that, in the first aspect, the plurality of substrates are made of silicon (ie, a silicon substrate).

A third aspect of the present invention is directed to the liquid chamber manufacturing method according to the second aspect, wherein a short wavelength arc lamp is used as a lamp light source.

A liquid chamber manufacturing method according to a fourth aspect is characterized in that, in the first, second or third aspect, a thermoplastic polyimide adhesive is used as the adhesive.

A liquid chamber manufacturing method according to a fifth aspect is characterized in that in the fourth aspect, a thermoplastic polyimide adhesive having a glass transition temperature of 120 ° C. or more is used.

According to a sixth aspect of the present invention, in the liquid chamber manufacturing method according to the fourth or fifth aspect, the step of bonding the substrates includes a short-time temporary bonding step using a lamp light source and a subsequent main bonding step using a lamp light source. In the final bonding step, heating is performed for a longer time or at a higher temperature than in the temporary bonding step.

[0014] In a seventh aspect of the invention, there is provided a method for producing a liquid chamber, wherein a thermosetting polyimide adhesive is used as the adhesive.

In the manufacturing method according to the first to seventh aspects, since the lamp heating is used for heating at the time of bonding, the bonding between the substrates can be performed in a short time. In addition, by using a lamp light source that matches the fundamental absorption wavelength of the substrate material, the substrate can be heated with high heating efficiency, and the bonding can be completed in a shorter time. When a silicon substrate that can be finely processed is used as a substrate, the substrate can be efficiently heated by using a short-wavelength arc lamp (wavelength is about 1 μm) as a lamp light source. Joining becomes possible. Furthermore, by using a polyimide resin-based adhesive, bonding with high ink resistance and a high Young's modulus becomes possible.

In particular, in the manufacturing method according to the sixth aspect, after applying an organic solvent solution of a thermoplastic polyimide-based adhesive, the organic solvent is removed from the applied film by drying and evaporating so as to be primarily cured (to form a film). ) Can eliminate tackiness. Further, since the bonding between the substrates can be performed by the film-like adhesive layer after removing the tackiness, a bonding process excellent in dust resistance and transportability can be realized. In addition, since the adhesive is of a thermoplastic resin type, bleeding does not occur, so that "adhesion" of the adhesive is suppressed. The above-mentioned "bleeding" means that either one of the main agent and the auxiliary agent (additive) having different melting points melts first and flows and diffuses.

On the other hand, the method of using the thermosetting polyimide-based adhesive is as follows: (1) As in the case of the thermoplastic polyimide-based adhesive, an adhesive mainly composed of a thermosetting polyimide is dissolved in an organic solvent. And (2) an organic solvent solution of a polyamic acid, which is a precursor of polyimide, is applied to the substrate surface, and then the polyamic acid is converted into a polyimide by baking (lamp heating).

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a method for producing a liquid chamber according to the present invention will be described in the order of steps with reference to the drawings. Example 1 (corresponding to claims 1, 2 and 4) Step 1: A substrate 1 and a substrate 3 for constituting (a part of) a liquid chamber of an ink jet printer head are prepared, and as shown in FIG. A thermoplastic polyimide adhesive 2 was applied to the bonding surface of the substrate 1 (or the substrate 3). As the adhesive 2, a liquid obtained by dissolving thermoplastic polyimide as a main component in an appropriate organic solvent was used. In this example, an adhesive made by dissolving a modified polyimide resin to which silicon was added as a plasticizer in NMP (n-methylpyrrolidone) manufactured by Nitto Denko Corporation was used. In addition, the substrates 1 and 3
Is made of silicon and has been subjected to predetermined fine processing in advance.

Step 2: After leveling the adhesive 2 on the substrate 1 at 50 ° C. for 10 minutes, pre-drying is performed at 170 ° C.
At 20 ° C. for 20 minutes, the solvent in the adhesive was evenly evaporated and the adhesive layer was formed into a film at 250 ° C. for 10 minutes.

Step 3: As shown in FIG. 2, a support member 7 composed of a support plate 5 and a support member 6 is placed above a lamp light source 4 composed of a halogen lamp 4a and a reflection plate 4b provided on the back side thereof. The substrate 1 on which the film-shaped adhesive layer was formed and placed on the support 6 was placed. Then, the substrate 3 is placed on the substrate 1.
Were aligned (positioned) and placed and contacted. The support plate 5 and the support 6 were made of quartz through which almost all visible light having a wavelength of 4 μm or less was transmitted. Then, the pressure plate 8 was placed on the substrate 3 and the substrates 1 and 3 were pressed at a pressure of ² kgf / cm ² .

Step 4: The output of the halogen lamp 4a was increased while maintaining the above-mentioned pressurized state, and the substrate and the film adhesive were heated. In this case, the temperature was raised to 250 ° C. in about 20 seconds, held at 250 ° C. for 30 seconds, and then the lamp output was lowered to complete the bonding between the substrates.

Step 5: Substrate 1 joined from supporting member 7
3 was taken out, allowed to cool to room temperature, and steps 1 to 4 were repeated to join another silicon substrate onto the substrate 3 to obtain a substrate joined body composed of three substrates. Thereafter, in the same manner, a desired number of substrates were joined to form a desired substrate laminate for the liquid chamber configuration of the ink jet printer head.

Example 2 (corresponding to claim 3) A silicon substrate having a fundamental absorption wavelength of about 1 μm was used as a silicon substrate, and a short-wavelength arc lamp (1 μm in wavelength) was used as a lamp light source. After processing in the same manner as in Steps 1 to 3 of Example 1, the output of the arc lamp was increased and the substrate and the film-like adhesive layer were heated to bond the substrates as in Step 4 above. In this case, the temperature was raised to 250 ° C. in 10 seconds, held at 250 ° C. for 30 seconds, and then the lamp output was lowered to complete the bonding. In this example, the substrate could be efficiently and more uniformly heated by using a lamp light source having a wavelength matching the absorption wavelength of the substrate.

Example 3 As shown in FIG. 3, the substrate laminate 10 (1
0a and 10b) were adhered to the diaphragm 13 to form the liquid chamber 11. In this case, the glass transition temperature (T
G) was carried out in the same manner as in Example 1 using a thermoplastic polyimide-based adhesive at 80 ° C.

Example 4 (corresponding to claim 5) A liquid chamber 11 shown in FIG. 4 was prepared in the same manner as in Example 3. However, in this case, TG is 130 ° C. as the adhesive 12.
Was used.

[Evaluation of Liquid Chambers Produced in Examples 3 and 4] As shown in FIG. 3, a piezoelectric element 20 was bonded to the liquid chamber 11 prepared in Example 3 using an epoxy adhesive 21. This bonding applies a pressure of 3 kgf between the diaphragm 13 and the piezoelectric element 20.
This was performed by heating the adhesive 21 to 110 ° C. while applying a pressure of / cm ² . Separately, the same piezoelectric element 20 as in FIG. 3 was bonded to the liquid chamber obtained in Example 4 under the same conditions as above.

As a result, in the bonded body of the liquid chamber 11 and the piezoelectric element 20 according to the third embodiment, the displacement of the substrate laminate 10a (to the right in FIG. 3) occurs. "Overhang" of the adhesive 12 in the opposite direction to the slip
12a was watched. It is considered that these are caused by the softening of the adhesive 12 during the bonding of the piezoelectric element 20 (because the TG is as low as 80 ° C.). On the other hand, in the bonded body of the liquid chamber 11 and the piezoelectric element 20 manufactured in Example 4, as shown in FIG. 4, the above problem was not observed.

Embodiment 5 (corresponding to claim 6) In Embodiment 1 shown in FIG. 1, a portion of the substrate 1 supported by the support 6 during heating of the lamp (a portion in contact with the support 6).
In addition, since the temperature of the outer peripheral portion of the substrate is low, the bonding of these portions may be incomplete. As a countermeasure for preventing this, a joining method combining temporary joining and subsequent main joining is effective. Hereinafter, an embodiment of this method will be described.

After the alignment of the substrates, in the temporary bonding step, the substrates were kept at 200 ° C. for 5 seconds while applying a low pressure (0.5 kgf / cm ² ). In this way, although an incompletely bonded portion remains on the bonding surface, an adhesive force enough to withstand handling was obtained. By repeating the temporary bonding, which is a low-pressure, short-time bonding process, the number of substrates required for the liquid chamber configuration of the inkjet printer head was temporarily bonded to form a temporary laminate. Lastly, as a final bonding step, the temporary laminate is subjected to a pressure of 3%.
By heating at 250 ° C. for 3 minutes while applying a pressure of kgf / cm ² , it is possible to compensate for the adhesion of the incompletely bonded portion during the temporary bonding, thereby realizing a highly reliable bonding in a short time. I was able to. For this main bonding, a pressure bonding apparatus having a pressure substrate with a built-in heater was used. Alternatively, the temporary laminate was pressed with a pressure jig, and this pressure jig was inserted into a heating furnace. A method of performing thermal compression bonding between substrates can also be adopted.

[0030]

As apparent from the above description, the following effects can be obtained according to the present invention. (1) Effects of the Inventions of Claims 1 to 7 When bonding substrates for forming a liquid chamber of an ink jet printer head, an adhesive layer is interposed between the substrates, and the substrates are intensively heated by lamp heating. By doing
Since the adhesive layer is heated to develop the adhesive force, the bonding between the substrates can be efficiently performed in a short time. In addition, by using a lamp light source that matches the fundamental absorption wavelength of the substrate material, the substrate can be heated with higher heating efficiency, and the bonding can be completed in a shorter time.

(2) Effect of the Second Invention Since a silicon substrate is used as a substrate, fine processing corresponding to a high-density head can be performed.

(3) Advantageous Effects of Claim 3 By using a silicon substrate having a fundamental absorption wavelength of about 1 μm as the substrate and an arc lamp having a short wavelength (1 μm) as the lamp light source, the substrate can be used. The adhesive layer can be efficiently heated, and bonding can be performed in a short time.

(4) Effect of the Invention of Claim 4 By using a thermoplastic polyimide-based adhesive as the adhesive, it is possible to easily realize bonding with good ink resistance and high Young's modulus. Further, after applying the liquid adhesive obtained by dissolving the adhesive in an organic solvent to the surface of the substrate, the organic solvent is removed by evaporation and primary curing (film formation) is performed to eliminate tackiness, and then the substrates are joined to each other. Therefore, a bonding process excellent in dust resistance and transportability can be realized. In addition, since the adhesive is a thermoplastic, bleeding (melting and flowing) and protrusion of the adhesive can be suppressed.

(5) Effect of the invention of claim 5 The polyimide adhesive has a glass transition temperature of 120.
By using a material having a temperature of not less than ° C., the polyimide adhesive is not softened in the subsequent step (adhesion of the piezoelectric element), so that the bonding failure after the subsequent step is suppressed.

(6) Effect of the Invention of Claim 6 Since temporary joining is performed using a lamp light source, temporary joining can be performed in a short time. In addition, the temporary bonding is repeated a required number of times according to the number of substrates to be bonded, and finally, the final bonding is performed once, so that the incompletely bonded portion at the time of the temporary bonding is accurately bonded, so that high reliability is achieved. Bonding can be performed in a short time.

[Brief description of the drawings]

FIG. 1 relates to a first embodiment, in which two to be joined to each other
It is sectional drawing which shows the state which applied the adhesive agent to one substrate surface among one board | substrate.

FIG. 2 is a cross-sectional view illustrating a step of bonding two substrates under pressure and heat according to the first embodiment.

FIG. 3 is a cross-sectional view showing a liquid chamber formed of a substrate laminate in Example 3, showing a case where a thermoplastic polyimide adhesive having a TG of 80 ° C. is used as an adhesive.

FIG. 4 is a cross-sectional view showing a liquid chamber formed of a substrate laminate in Example 4, where TG is 130 ° C. as an adhesive;
1 shows a case where the thermoplastic polyimide adhesive of the present invention is used.

[Explanation of symbols]

 1, 3 Substrate 2 Thermoplastic polyimide adhesive 4 Lamp light source 4a Halogen lamp 4b Reflector 5 Support plate 6 Support 7 Support member 8 Pressing plate 10 Substrate laminate 10a Substrate laminate 10b Substrate laminate 11 Liquid chamber 12 Adhesive 12a Extrusion of adhesive 13 Vibration plate 20 Piezoelectric element 21 Epoxy adhesive

Claims (7)

[Claims] When producing a liquid chamber of an ink jet printer head using a substrate laminate formed by joining and laminating a plurality of substrates, an adhesive layer which develops adhesive force by heating is interposed between substrates to be joined. And heating the adhesive layer with a lamp light source to bond the substrates to each other to obtain the substrate laminate. 2. The method according to claim 1, wherein the plurality of substrates are made of silicon. 3. The method according to claim 2, wherein a short wavelength arc lamp is used as the lamp light source. 4. The adhesive according to claim 1, wherein said adhesive is a thermoplastic polyimide adhesive.
3. The method for producing a liquid chamber of an ink jet printer head according to item 1. 5. The method according to claim 4, wherein the thermoplastic polyimide-based adhesive has a glass transition temperature of 120 ° C. or higher. 6. The bonding step between the substrates includes a short-time temporary bonding step using a lamp light source and a subsequent main bonding step using a lamp light source. 6. The method according to claim 4, wherein heating is performed for a long time or at a high temperature. 7. The method according to claim 1, wherein a thermosetting polyimide adhesive is used as said adhesive.
3. The method for producing a liquid chamber of an ink jet printer head according to item 1.