JPH09141879A - Manufacture of ink jet print head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an adhesive from entering the grooves formed on a base plate by the capillarity when the base plate and a top plate are bonded to each other in a manufacturing process of an ink jet print head. SOLUTION: When a high resolution ink jet print head in which a density of grooves 8 formed on a base plate 2 is 4/mm or greater is manufactured, a high viscosity adhesive 17 of which viscosity is 2000 cps or greater is uniformly and thinly coated on a transfer member 16. A face of the transfer member 16 coated with the adhesive 17 is brought into contact with a face of the base plate or a top plate to be bonded so that the adhesive 17 is transferred to the face to be bonded, then the base plate 2 and top plate are bonded with the adhesive 17 therebetween. The viscosity of the adhesive 17 is high so that when the base plate 2 and top plate are bonded with the adhesive 17 therebetween, the adhesive 17 does not enter the grooves 8 by the capillarity.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a method for manufacturing an on-demand type ink jet printer head.

[0002]

2. Description of the Related Art Conventionally, a nozzle plate having an ink discharge port is fixed to the tips of a large number of pressure chambers connected in parallel to an ink supply unit, and the ink pressure in the pressure chambers is selectively increased according to a print command. An on-demand inkjet printer head is known in which an ink droplet is ejected from an ink ejection port.

As a method of manufacturing such an ink jet printer head, there is known a method in which a substrate having at least a part formed of a piezoelectric member is processed with a large number of grooves and a top plate is bonded to the substrate with an adhesive. There is. However, since the grooves are extremely fine, there is a drawback that the adhesive agent for bonding the substrate and the top plate enters the grooves to clog the grooves and deteriorates ink droplet ejection performance.

As a method of manufacturing an ink jet printer head which has solved the above drawbacks, Japanese Patent Publication No. 60-52 is available.
As disclosed in Japanese Patent Publication No. 951), a low-viscosity adhesive is spread evenly on a flat plate with a rubber roller, and a grooved substrate is pressed against the spread adhesive on the flat plate to remove the adhesive. There is one that is transferred to a substrate, and the substrate and the top plate are joined and bonded to each other via the transferred adhesive.

[0005]

[Problems to be Solved by the Invention] Japanese Patent Publication No. 60-5295
In the manufacturing method described in Japanese Patent Laid-Open No. 1, a low-viscosity adhesive is used to spread the adhesive thinly and evenly on a flat plate with a rubber roller. Therefore, when the substrate and the top plate are joined together, the adhesive enters into the groove due to the capillary phenomenon and clogs the groove. In particular, when manufacturing a high-resolution inkjet printer head with a groove density of 4 lines / mm or more, the groove is likely to be clogged with the adhesive.

Therefore, the invention according to claim 1 is an ink jet printer which can prevent the adhesive from entering into the groove formed in the substrate due to the capillary phenomenon and clogging when the substrate and the top plate are bonded with the adhesive. A method for manufacturing a head is provided.

According to the second aspect of the present invention, when the substrate and the top plate are bonded to the nozzle plate with the adhesive, it is possible to prevent the adhesive from entering into the groove formed in the substrate due to the capillary phenomenon and clogging. A method for manufacturing an inkjet printer head is provided.

According to the third aspect of the present invention, there is provided a method for manufacturing an ink jet printer head which can favorably apply an adhesive to a transfer member and transfer the adhesive from the transfer member to an adhesive surface of a substrate or the like.

[0009]

According to the first aspect of the present invention,
A substrate including at least one piezoelectric member polarized in the plate thickness direction, a plurality of side walls, at least some of which are alternately formed on the substrate, are formed of the piezoelectric member, and four or more / mm or more located between these side walls Groove and an electrode provided on the side wall,
In a method for manufacturing an inkjet printer head having a number of pressure chambers formed by adhering a top plate covering the upper part of the groove and a nozzle plate covering the front part of the groove to the substrate, a high viscosity of 2000 cps or more is obtained. The adhesive is applied thinly and uniformly to the transfer member, and the adhesive-applied surface of the transfer member is brought into contact with either one of the adhesive surfaces for adhering the substrate and the top plate to each other. Is transferred to the bonding surface, and the substrate and the top plate are bonded and bonded via the transferred adhesive, so that the adhesive is 2000c.
Since it has a high viscosity of ps or more, it is possible to prevent the adhesive from entering the groove due to a capillary phenomenon when the substrate and the top plate are joined via this adhesive.

According to a second aspect of the present invention, a substrate including at least one piezoelectric member polarized in the plate thickness direction, and a plurality of side walls alternately formed on the substrate, at least a part of which are made of the piezoelectric member, are provided. Formed by adhering 4 / mm or more grooves positioned between the side walls of the groove, electrodes provided on the side walls, a top plate covering the upper part of the groove and a nozzle plate covering the front part of the groove to the substrate. In a method for manufacturing an inkjet printer head having a large number of pressure chambers,
A high-viscosity adhesive of cps or more is thinly and uniformly applied to the transfer member, and the adhesive-coated surface of the transfer member is applied to the bonding surface of the nozzle plate of the member that bonds the substrate and the top plate. Transfer this adhesive to the adhesive surface by contacting,
Since the substrate and the top plate and the nozzle plate are bonded and bonded through the transferred adhesive, the adhesive is 2000
Since it has a high viscosity of cps or more, it is possible to prevent the adhesive from entering the groove due to the capillary phenomenon when the substrate and the top plate are joined to the nozzle plate via this adhesive.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the transfer member is an olefin resin member, so that the adhesive can be applied thinly and uniformly to the transfer member. Good transfer of the adhesive to the adhesive surface of the top plate can be performed.

[0012]

FIG. 1 shows a first embodiment of the present invention.
A description will be given with reference to FIG. As shown in FIG. 1, the inkjet printer head 1 has a top plate 3 with respect to a substrate 2.
And the nozzle plate 4 are bonded together.

The substrate 2 is formed in a three-layer structure by bonding the bottom plate 5 and the two piezoelectric members 6 and 7 together. The bottom plate 5
Is made of ceramics or glass that has high rigidity and little thermal deformation, and has a plate thickness of 0.5 to 5 mm. The piezoelectric members 6 and 7 are bonded in such a manner that they are polarized in the plate thickness direction so that the polarization directions are opposite.

By performing groove processing on the substrate 2, a large number of parallel grooves 8 reaching the inside of the piezoelectric member 6 from the upper surface of the piezoelectric member 7 and a large number of side walls 9 separating these grooves 8 are alternately formed. To form. This groove processing is performed by using a diamond wheel or the like of a dicing saw used for cutting an IC wafer, and these grooves 8 are formed in a shape in which the front side of the substrate 2 is opened and the inner side is closed. The dimensions of the groove 8 are determined according to the specifications of the inkjet printer head, and for example, the depth dimension is 0.2 to 1 mm, the width dimension is 20 to 200 μm, and the length dimension is 5 to 50 mm.

Next, the substrate 2 having the groove 8 and the side wall 9 formed thereon is subjected to electroless plating to form the electrode 10 on the side surface of the side wall 9 and the piezoelectric member 7 A wiring pattern 11 continuous with these electrodes 10 is formed on the upper surface. Furthermore, when the inkjet printer head 1 is completed using this substrate 2, the electrode 1
In order to prevent 0 from contacting the ink, the electrode 10
An insulating film 12 is coated on the above.

The top plate 3 is bonded to the substrate 2 on which the groove 8 and the side wall 9 and the electrode 10 and the insulating film 12 are formed in this manner so as to cover the upper portion of the groove 8 and the groove 8. The nozzle plate 4 is adhered so as to cover the front surface, and each groove 8 is surrounded by the top plate 3 and the nozzle plate 4 to form a large number of pressure chambers 13. The nozzle plate 4 has a large number of ink ejection ports 14 communicating with the pressure chambers 13, and the top plate 3
An ink supply path 15 is formed on the lower surface of the ink supply path 13 to communicate with each pressure chamber 13 and to connect an ink supply pipe (not shown) for supplying ink to these pressure chambers 13.

Here, the step of adhering the substrate 2 and the top plate 3 will be described with reference to FIG. An adhesive 17 is thinly and uniformly applied to one surface of a flexible PET (polyethylene terephthalate) film 16 which is a transfer member.
As the adhesive 17, a high-viscosity adhesive, for example, a two-component room temperature curing type DP-460 (trade name) manufactured by Sumitomo 3M, which has a viscosity of about 80,000 cps, is used. The same weight of toluene as a solvent is mixed and diluted to obtain a mixed solution having a viscosity of several tens to several hundreds tens cps. This mixed solution is applied on the PET film 16 by a coating method such as spin coating, roll coating, or dipping, and after coating, it is dried for a while to volatilize toluene,
The adhesive returned to high viscosity is left on the PET film 16. In the case of spin coating, the rotation speed is 1000 to 5
000 rpm, the adhesive agent 17 is
It can be applied to a thickness of μm.

After the adhesive 17 is applied to the PET film 16, the surface of the PET film 16 on which the adhesive 17 is applied is brought into contact with the surface of the substrate 2 to be adhered to the top plate 3, and the PET film 16 is elastically pressed from above. The material roller 18 is pressed and moved one to several rotations to transfer the adhesive 17 onto the adhesive surface of the substrate 2.

The top plate 3 is bonded to the adhesive surface of the substrate 2 to which the adhesive 17 is transferred in this manner, and the adhesive 17 is cured by maintaining the pressure for a certain period of time to cure the substrate 2 and the top plate 3. Glue and. Room temperature curing type DP as the adhesive 17
When -460 is used, it may be left as it is, but it can be completely cured by placing it in an oven at 65 ° C for 2 hours or more.

Here, when the substrate 2 and the top plate 3 are bonded together, it is necessary to prevent the groove 8 from being blocked by the adhesive 17, and this is done to select the adhesive 17 to be used. The experimental results will be described based on Tables 1 to 3. In this experiment, the density of the grooves 8 was 4 / mm, 8 / mm, 12 /
3 types of substrate 2 having a width of 8 mm were produced, and the width of the groove 8 and the side wall 9 were formed.
The width dimension of the groove 8 was 1: 1 and the depth dimension of the groove 8 was 3 times the width dimension. Transfer of the adhesive 17 to the adhesive surface of the substrate 2 is performed by applying the PET film 16 coated with the adhesive 17 to the substrate 2
This is performed by bringing the elastic material roller 18 into contact with the adhesive surface of and rolling the elastic material roller 18 against it. The thickness of the adhesive 17 applied on the PET film 16 is 5 μm, 10
There are three types, μm and 15 μm. After the adhesive 17 was transferred to the adhesive surface of the substrate 2, the glass top plate 3 was joined and adhered, and after the adhesive 17 was cured, the degree of clogging of the groove 8 with the adhesive 17 was observed.

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

[Table 3]

The evaluation criteria in each table mean the following. ◯: The clogging with the adhesive is good when it is less than 10% of the groove cross-sectional area, which is the state shown in FIG. 5 (a). Δ: Clogging due to the adhesive is 10% or more of the groove cross-sectional area 30
If it is less than%, it can be used and is in the state shown in FIG. X: Clogging due to the adhesive is 30% or more of the groove cross-sectional area and unusable, which is the state shown in FIG. 5 (c). Δ *, × *: Clogging was caused by a large amount of the adhesive, and the adhesive did not enter the groove due to the capillary phenomenon, and the state shown in FIG. is there.

From the above experimental results, it has been found that if the viscosity of the adhesive 17 is 2000 cps or more, it is possible to prevent the adhesive 17 from entering the groove 8 due to the capillary phenomenon. As an exception, the one-part epoxy resin with a viscosity of 2000 cps gave poor results because the viscosity decreased during heat setting to a minimum viscosity of about 1000 cps. Similarly, the viscosity of the other one-component epoxy resin also decreases during heat curing, but good results were obtained because the minimum viscosity was 2000 cps or more.

From the above experimental results, the above-mentioned DP-
460 is suitable as the adhesive 17 to be used, but since it is a two-liquid type, it has a limitation that the bonding work must be performed in a short time, and when an oil-based ink is used, the solvent resistance is poor. . Therefore, as the adhesive 17 having excellent solvent resistance without being restricted by the bonding work time, a one-component heat-curable adhesive, for example, AH3041W (trade name) manufactured by Taoka Chemical Industry Co., Ltd. having a viscosity of 25000 cps is used. Can be used. When this AH3041W is used, it is applied to the PET film 16 with a viscosity of several tens to several hundreds of cps by mixing with 30% by weight of toluene, and dried to volatilize the toluene, and then the adhesive surface of the substrate 2 is applied. Transfer to.

After the substrate 2 and the top plate 3 are bonded, the substrate 2 and the top plate 3 are cut with a diamond wheel of a dicing saw or the like to form a bonding surface for bonding the nozzle plate 4. The nozzle plate 4 can be formed by an electroforming method, an etching method, a laser processing method, or the like. When it is formed of a conductor, an insulating film for the electrode 10 is formed. The ink ejection port 14 has a diameter of 20 to 100 μm, and its shape is formed in a taper shape in which the diameter gradually decreases toward the tip as shown in FIG. 4 in consideration of fluid resistance.

The nozzle plate 4 is bonded to the bonding surface formed by cutting the substrate 2 and the top plate 3 as described above.
The adhesive 17 is transferred to the adhesive surface using the PET film 16 coated with, and the substrate 2 and the top plate 3 and the nozzle plate 4 are bonded and bonded via the adhesive 17. Since there is no warp on this adhesive surface, the PET film 16
Alternatively, the adhesive 17 may be applied to a hard flat plate, and the adhesive surface may be pressed against the flat plate to transfer the adhesive 17.

When the nozzle plate 4 was adhered, an experiment was conducted under the same conditions as those shown in Tables 1 to 3 above. If a highly viscous adhesive 17 having a viscosity of 2000 cps or more was used, the substrate 2 It was also found that when the nozzle plate 4 was joined to the top plate 3, it was possible to prevent the adhesive from entering the groove 8 due to the capillary phenomenon.

In the ink jet printer head 1 having such a structure, when a voltage is applied to the electrode 10 through the wiring pattern 11 while the ink is supplied into the pressure chamber 13, as shown in FIG. The side wall 9 formed by 6 and 7 undergoes shear mode deformation in the direction of increasing the volume of the pressure chamber 13, and eventually the side wall 9 rapidly returns to the initial position. Then, when the side wall 9 suddenly returns to the initial position, the ink in the pressure chamber 13 is pressurized, so that part of the ink is ejected from the ink ejection port 14 as an ink droplet. At the time of ejecting the ink droplets, the even-numbered pressure chambers 13 and the odd-numbered pressure chambers 13 are alternately pressurized to prevent crosstalk. As shown in FIG. 4, the ink discharge port 14 is formed in a taper shape in which the diameter gradually decreases toward the tip end portion, so that the ink droplet is discharged from the ink discharge port 14.
Can be efficiently discharged.

Here, since the substrate 2 is formed by laminating the bottom plate 5 and the two piezoelectric members 6 and 7 and adhering them to each other, the difference in the material of each member 5, 6 and 7 and the thickness of A warp caused by the difference is generated, and the warp increases as the size of the substrate 2 increases. In order to transfer the adhesive agent 17 to the adhesive surface of the substrate 2 in which such warpage occurs, the PET film 16 coated with the adhesive agent 17 is brought into contact with the adhesive surface, and the elastic material roller 18 is pressed against it. The adhesive 17
The PET film 16 coated with is bent according to the warp of the substrate 2, and the adhesive 17 can be transferred to the adhesive surface of the substrate 2 without causing transfer unevenness. In particular, by pressing the elastic material roller 18 against the PET film 16 to roll it, the adhesive 17 can be satisfactorily transferred even when the substrate 2 becomes large and the warp becomes large. In this manner, the transfer of the adhesive 17 to the adhesive surface of the substrate 2 can be performed uniformly without causing transfer unevenness, so that the substrate 2 and the top plate 3 can be reliably adhered.

In the adhesion of the substrate 2 and the top plate 3 and the adhesion of the nozzle plate 4 to the substrate 2 and the top plate 3, a high-viscosity adhesive 1 having a viscosity of 2000 cps or more is used.
7 is used, the adhesive 17 does not enter the groove 8 by the capillary phenomenon when the members to be bonded are joined via the adhesive 17.
It is possible to prevent the groove 8 from being clogged by 7.

The PET film 16 is used for transferring the adhesive 17 to the adhesive surface of the substrate 2 for the following reason. Considering only the transfer efficiency, it is preferable to use a fluororesin or the like to which the adhesive 17 does not easily adhere, but for example, when the adhesive 17 is applied to a Teflon film, the adhesive 17 becomes a ball and is applied uniformly. I can't. On the other hand, if only the uniformity of the coating thickness is taken into consideration, a material having an adhesive property, for example, a polyimide film may be used, but in that case, the transfer efficiency to the adhesive surface of the substrate 2 is deteriorated and the transfer unevenness is caused. Cause Therefore, by using an olefin resin film such as PET, PP (polypropylene) or PE (polyethylene), both the uniformity of the coating thickness and the transfer efficiency are improved.

In this embodiment, the case where the high-viscosity adhesive 17 is diluted with a solvent such as toluene in order to apply it to the PET film 16 has been described as an example, but the screen printing method without dilution is used. You may print with. When this screen printing method is used, it can be applied to a thickness of 10 to 30 μm.

Further, in this embodiment, PET is used to transfer the adhesive 17 onto the surface of the substrate 2 which is to be adhered to the top plate 3.
Although the case where the film 16 and the elastic material roller 18 are used has been described as an example, when warpage is not a problem, the adhesive 17 is applied to a hard flat plate instead of the PET film 16, The flat plate may be pressed against the adhesive surface to transfer the adhesive 17.

In the present embodiment, the case where the adhesive 17 is transferred to the bonding surface of the substrate 2 with the top plate 3 has been described as an example, but the bonding surface of the substrate 2 with the substrate 2 is bonded. The agent 17 may be transferred and the substrate 2 and the top plate 3 may be bonded via the adhesive 17.

Next, a second embodiment of the present invention will be described with reference to FIG.
It will be described based on. The same parts as those in the above-described embodiment are designated by the same reference numerals, and different parts will be described. The inkjet printer head 1a of the present embodiment has a substrate 2a formed by laminating and bonding two piezoelectric members 6a and 7a. In this way, the substrate 2
Since a is formed by bonding only members made of the same material, it is possible to reduce the warpage of the substrate 2a.

[0038]

According to the first aspect of the present invention, when the substrate and the top plate are bonded by the adhesive, it is possible to prevent the adhesive from entering the groove formed in the substrate due to the capillary phenomenon and clogging. it can.

According to the second aspect of the present invention, when the substrate and the top plate are bonded to the nozzle plate with the adhesive, the adhesive may enter into the groove formed in the substrate due to a capillary phenomenon and become clogged. It can be prevented.

According to the third aspect of the invention, the application of the adhesive to the transfer member and the transfer of the adhesive from the transfer member to the adhesive surface of the substrate or the like can be satisfactorily performed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an inkjet printer head according to a first embodiment of the present invention with a part thereof cut away.

FIG. 2 is a front view showing a step of transferring an adhesive to an adhesive surface of a substrate.

FIG. 3 is a vertical sectional front view showing a shear mode deformation state of a piezoelectric member.

FIG. 4 is a vertical sectional side view showing the shape of an ink ejection port.

FIG. 5 is an explanatory diagram showing a clogged state of a groove depending on the type of adhesive.

FIG. 6 is a vertical sectional front view showing an inkjet printer head according to a second embodiment of the present invention.

[Explanation of symbols]

 1, 1a Inkjet printer head 2, 2a Substrate 6, 7, 6a, 7a Piezoelectric member 8 Groove 9 Side wall 10 Electrode 13 Pressure chamber 16 Transfer member 17 Adhesive

Claims (3)

[Claims] 1. A substrate including at least one piezoelectric member polarized in the plate thickness direction, and at least some of the substrates alternately formed on the substrate are located between a plurality of side walls of the piezoelectric member and between these side walls. 4 / mm or more grooves, electrodes provided on the side walls, a top plate that covers the upper portions of the grooves, and a nozzle plate that covers the front portion of the grooves, and a large number of pressure chambers formed by adhering to the substrate. In the method for manufacturing an inkjet printer head having the above, a high-viscosity adhesive having a viscosity of 2000 cps or more is thinly and uniformly applied to a transfer member, and the adhesive-coated surface of the transfer member is bonded to the substrate and the top plate. An ink jet characterized by being brought into contact with either one of the respective adhesive surfaces to transfer the adhesive to the adhesive surface, and bonding the substrate and the top plate by bonding via the transferred adhesive. Printer head manufacturing method. 2. A substrate including at least one piezoelectric member polarized in the plate thickness direction, and at least some of the substrates alternately formed on the substrate are located between a plurality of side walls of the piezoelectric member and between these side walls. 4 / mm or more grooves, electrodes provided on the side walls, a top plate that covers the upper portions of the grooves, and a nozzle plate that covers the front portion of the grooves, and a large number of pressure chambers formed by adhering to the substrate. In the method for manufacturing an inkjet printer head having the above, a high-viscosity adhesive having a viscosity of 2000 cps or more is thinly and uniformly applied to a transfer member, and the adhesive-coated surface of the transfer member is bonded to the substrate and the top plate. The adhesive member is brought into contact with the adhesive surface of the nozzle plate, the adhesive is transferred to the adhesive surface, and the substrate and the top plate and the nozzle plate are bonded to each other via the transferred adhesive and bonded. Features And a method for manufacturing an inkjet printer head. 3. The method of manufacturing an ink jet printer head according to claim 1, wherein the transfer member is an olefin resin member.