JP2000296616A - Ink jet recording head and ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording head and an ink jet recording apparatus simplified in its structure to be reduced in production cost and prevented from the deformation and crack of a substrate. SOLUTION: In an ink jet recording head equipped with a nozzle forming member 16 having a plurality of nozzle orifices 15 emitting ink, a flow channel forming substrate 10 wherein the pressure generating chambers 12 bonded to the nozzle forming member 16 and communicating with the nozzle orifices 15 are demarcated and the piezoelectric element 300 provided to the surface opposite to the surface to which the nozzle forming member 16 is bonded of the flow channel forming substrate 10 to generate a pressure change in the pressure generating chambers 12, a reservoir forming member 20 having a reservoir part 21 constituting at least a part of a reservoir 100 communicating with the pressure generating chambers 12 to supply ink to the pressure generating chambers 12 is bonded to the surface on the side wherein the piezoelectric element 300 is formed of the flow channel forming substrate 10 and has a piezoelectric element holding part 24 ensuring a space of a degree not obstructing the motion of the piezoelectric element 300 to the region opposed to the piezoelectric element 300 to seal the space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a part of a pressure generating chamber which communicates with a nozzle opening for discharging ink droplets, which is constituted by a vibrating plate. The present invention relates to an ink jet recording head and an ink jet recording apparatus that eject ink droplets by displacement.

[0002]

2. Description of the Related Art A part of a pressure generating chamber communicating with a nozzle opening for discharging ink droplets is constituted by a vibrating plate, and the vibrating plate is deformed by a piezoelectric element to pressurize the ink in the pressure generating chamber to pass through the nozzle opening. Two types of ink jet recording heads that eject ink droplets have been commercialized, one using a longitudinal vibration mode piezoelectric actuator that expands and contracts in the axial direction of the piezoelectric element, and the other using a flexural vibration mode piezoelectric actuator. ing.

In the former method, the volume of the pressure generating chamber can be changed by bringing the end face of the piezoelectric element into contact with the diaphragm, so that a head suitable for high-density printing can be manufactured. There is a problem in that a difficult process of cutting into a comb shape in accordance with the arrangement pitch of the openings and an operation of positioning and fixing the cut piezoelectric element in the pressure generating chamber are required, and the manufacturing process is complicated.

On the other hand, in the latter, a piezoelectric element can be formed on a diaphragm by a relatively simple process of sticking a green sheet of a piezoelectric material according to the shape of a pressure generating chamber and firing the green sheet. In addition, there is a problem that a certain area is required due to the use of flexural vibration, and that high-density arrangement is difficult.

On the other hand, in order to solve the latter disadvantage of the recording head, a uniform piezoelectric material layer is formed by a film forming technique over the entire surface of the diaphragm as disclosed in Japanese Patent Application Laid-Open No. 5-286131. A proposal has been made in which the piezoelectric material layer is cut into a shape corresponding to the pressure generating chambers by a lithography method, and a piezoelectric element is formed so as to be independent for each pressure generating chamber.

According to this, the operation of attaching the piezoelectric element to the diaphragm becomes unnecessary, and not only can the piezoelectric element be manufactured by a precise and simple method such as lithography, but also the thickness of the piezoelectric actuator can be reduced. There is an advantage that it can be made thin and can be driven at high speed. In this case,
By providing at least only the upper electrode for each pressure generating chamber while keeping the piezoelectric material layer on the entire surface of the diaphragm, the piezoelectric actuator corresponding to each pressure generating chamber can be driven.

[0007] In such an ink jet recording head, a reservoir serving as a common ink chamber for each pressure generating chamber is generally formed by laminating a plurality of substrates. Is supplied with ink. Further, the reservoir is provided with a compliance section for absorbing a pressure change at the time of driving the piezoelectric element in order to keep the internal pressure of the reservoir constant.

[0008]

However, the number of substrates used to form the reservoir is large, and in particular, the number of substrates laminated to form the compliance section is large, resulting in high material and assembly costs. There is.

Further, in the above-described ink jet recording head, since the number of nozzles is increased, it is necessary to make the reservoir large enough to supply ink to each pressure generating chamber. In addition, there is a problem that the strength of the substrate forming the reservoir necessarily decreases. Therefore, when heat is applied to these substrates in the mounting process, there is a problem that the substrates warp due to thermal expansion and cracks occur.

Further, when silicon is used for the substrate defining the pressure generating chamber, it is difficult to adhere at a high temperature due to a difference in thermal expansion coefficient from other substrates, and there are also problems such as an increase in the number of assembly steps. is there.

In view of such circumstances, it is an object of the present invention to provide an ink jet recording head and an ink jet recording apparatus in which the structure is simplified, the manufacturing cost is reduced, and deformation and cracking of the substrate are prevented. .

[0012]

According to a first aspect of the present invention, there is provided a nozzle forming member having a plurality of nozzle openings for discharging ink, the nozzle forming member being joined to the nozzle forming member and being provided with the nozzle opening. A flow path forming substrate defining a pressure generating chamber communicating with each other, and a pressure generating chamber provided on a surface of the flow path forming substrate opposite to a surface to which the nozzle forming member is joined via a diaphragm. In the ink jet recording head comprising a piezoelectric element that changes the volume of the chamber,
Forming a reservoir on the surface of the flow path forming substrate on which the piezoelectric element is formed, the reservoir having at least a part of a reservoir that communicates with the pressure generating chamber and supplies ink to each pressure generating chamber. A member is joined, and the reservoir forming member has a piezoelectric element holding portion that seals the space in a state where a space is secured in a region facing the piezoelectric element.

According to the first aspect, the number of stacked substrates for forming the reservoir can be reduced, the structure can be simplified, and the piezoelectric element is hermetically sealed in the piezoelectric element holding portion. Destruction of the piezoelectric element due to the environment is prevented.

According to a second aspect of the present invention, in the first aspect, the piezoelectric element holding section is partitioned by partition walls for each piezoelectric element, and the partition walls are joined to the flow path forming substrate. An ink jet recording head is characterized in that:

In the second aspect, the rigidity of the peripheral wall that partitions the pressure generating chamber is increased, and the peripheral wall is prevented from falling down when the piezoelectric element is driven.

According to a third aspect of the present invention, in the first or second aspect, a part of the reservoir is formed with the flow path forming substrate in communication with the reservoir part of the reservoir forming member together with the reservoir part. An ink jet recording head is characterized in that the ink jet recording head has a communicating portion.

In the third aspect, the reservoir is constituted by the reservoir portion and the communication portion, so that a relatively large reservoir can be easily formed.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the reservoir and each of the pressure generating chambers are connected to each other via an ink supply path whose flow path is relatively narrower than the reservoir. An ink jet recording head is characterized in that it is communicated.

In the fourth aspect, since the ink is supplied from the reservoir to the pressure generating chamber via the ink supply path having a relatively narrow flow path, the amount of bubbles mixed into the ink is suppressed.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, ink is introduced into the reservoir portion of the reservoir forming member so as to communicate with the outside and supply ink to the reservoir. An ink jet type recording head characterized in that the mouth is communicated.

In the fifth aspect, ink is supplied from the ink inlet to the reservoir.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the reservoir portion is formed in a width direction of the plurality of pressure generating chambers arranged in parallel. The feature is the ink jet recording head.

In the sixth aspect, ink is supplied from a reservoir common to each pressure generating chamber.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, a part of the reservoir portion of the reservoir forming member has a flexible portion having flexibility. In the ink jet recording head.

In the seventh aspect, the change in the internal pressure of the reservoir is absorbed by the deformation of the flexible portion,
The pressure inside the reservoir is always kept constant.

According to an eighth aspect of the present invention, in the seventh aspect, a through-hole penetrating without communicating with the pressure generating chamber is provided in the flow path forming substrate in a region corresponding to the reservoir section. And the flexible portion between the penetrating portion and the reservoir portion.

In the eighth aspect, the flexible portion provided between the penetrating portion and the reservoir portion is elastically deformed, thereby absorbing a pressure change in the reservoir and keeping the inside of the reservoir always at a constant pressure. Is done.

According to a ninth aspect of the present invention, in the ink jet type according to the eighth aspect, the penetrating portion is formed across a width direction of the plurality of pressure generating chambers arranged in parallel. In the recording head.

In the ninth aspect, the flexible portion is formed with an area capable of sufficiently absorbing the pressure change in the reservoir.

A tenth aspect of the present invention is the ink jet recording head according to the eighth or ninth aspect, wherein the penetrating portion is formed by etching together with the pressure generating chamber.

In the tenth aspect, the flexible portion can be formed relatively easily.

According to an eleventh aspect of the present invention, in any one of the seventh to tenth aspects, the flexible portion is provided by joining a flexible member. In the head.

In the eleventh aspect, the flexible portion can be easily provided by joining the flexible members.

A twelfth aspect of the present invention is the ink jet recording head according to the eleventh aspect, wherein the flexible member is made of a metal or ceramic thin film.

In the twelfth aspect, the flexible portion can be easily formed by forming a thin film.

A thirteenth aspect of the present invention is the ink jet recording head according to the eleventh aspect, wherein the flexible member is made of a resin material.

In the thirteenth aspect, since the flexible portion is made of a resin member, it can be easily formed.

A fourteenth aspect of the present invention is the ink jet recording head according to the thirteenth aspect, wherein the resin material is selected from the group consisting of a fluororesin, a silicone resin and a silicone rubber. .

In the fourteenth aspect, the use of the specific resin material allows the flexible portion to be reliably formed.

A fifteenth aspect of the present invention is the ink jet recording head according to the eleventh aspect, wherein the flexible member includes a layer having a tensile stress.

In the fifteenth aspect, destruction of the flexible film can be prevented without buckling of the flexible film.

A sixteenth aspect of the present invention is the ink jet recording head according to the eleventh aspect, wherein the flexible member has only the diaphragm and the film constituting the piezoelectric element. .

In the sixteenth aspect, when forming the piezoelectric element, the flexible member can be easily formed together therewith.

According to a seventeenth aspect of the present invention, in any one of the eleventh to sixteenth aspects, another substrate having a through hole at least in a region opposed to the flexible portion is joined to the flexible member. An ink jet recording head is characterized in that:

In the seventeenth aspect, the strength of the portion other than the flexible portion is improved, and the durability of the head is improved.

According to an eighteenth aspect of the present invention, in any one of the eleventh to seventeenth aspects, a surface of the flexible member opposite to the reservoir portion is formed with a ridge extending in a planar direction. An ink jet recording head is provided with a beam portion.

In the eighteenth aspect, the beam portion
The strength of the flexible film increases, and the durability improves.

A nineteenth aspect of the present invention is the ink jet recording head according to the eighteenth aspect, wherein the beam portions are formed in a lattice shape.

In the nineteenth aspect, the strength of the flexible film is increased and the durability is improved by the lattice-shaped beams.

According to a twentieth aspect of the present invention, in any one of the first to nineteenth aspects, the reservoir portion of the reservoir forming member is provided between the side walls defining the reservoir portion and facing each other. An ink jet recording head is provided with at least one beam-shaped reinforcing portion.

In the twentieth aspect, the rigidity of the reservoir portion is improved by the reinforcing portion, and cracking of the reservoir forming member due to thermal stress during mounting is prevented.

According to a twenty-first aspect of the present invention, in the twentieth aspect, at least a part of the reinforcing portion has a thickness smaller than other portions of the reservoir forming member. It is in.

In the twenty-first aspect, the rigidity of the reservoir portion is improved without deteriorating the function of the reservoir.

According to a twenty-second aspect of the present invention, in the twenty-first aspect, at least a portion of the reinforcing portion on the side of the flow path forming substrate is removed, and the thickness of the reinforcing portion is smaller than other portions. Ink-jet recording head.

According to the twenty-second aspect, the function of the reservoir can be reliably maintained, and the rigidity of the reservoir is improved.

According to a twenty-third aspect of the present invention, in any one of the twentieth to twenty-second aspects, the reinforcing portion is formed along a longitudinal direction of the piezoelectric element. It is in.

In the twenty-third aspect, cracks due to thermal stress during mounting of the reservoir forming board are reliably prevented.

According to a twenty-fourth aspect of the present invention, in any one of the first to twenty-third aspects, a displacement of the piezoelectric element is detected in at least a part of a region of the reservoir forming member facing the piezoelectric element. An ink jet type recording head is provided with a through hole for detection.

In the twenty-fourth aspect, the displacement of the piezoelectric element can be easily detected from outside the reservoir forming member.

According to a twenty-fifth aspect of the present invention, in the twenty-fourth aspect, the piezoelectric element holding portion is provided so as to penetrate the reservoir forming member and is sealed with a transparent member. An ink jet recording head is characterized in that it also serves as

In the twenty-fifth aspect, displacement of the piezoelectric element can be detected with the piezoelectric element sealed.

[0062] A twenty-sixth aspect of the present invention is the ink-jet recording head according to the twenty-fifth aspect, wherein the transparent member forms the flexible portion.

In the twenty-sixth aspect, the change in the internal pressure of the piezoelectric element holding section is absorbed by the deformation of the permeable member, and the internal pressure of the piezoelectric element holding section is kept constant.

According to a twenty-seventh aspect of the present invention, in any one of the first to twenty-sixth aspects, the wiring on the flow path forming substrate drawn from the piezoelectric element and the flow path forming substrate of the reservoir forming member are provided. A connection wiring for connecting to a wiring provided in a region on the opposite side to the wiring, and an external wiring is connected to the wiring provided in a region on the opposite side of the reservoir forming member. In the recording head.

In the twenty-seventh aspect, the wiring drawn from the piezoelectric element and the external wiring are connected in the region on the opposite side of the reservoir forming member, so that the head can be downsized.

According to a twenty-eighth aspect of the present invention, in the ink-jet recording head according to the twenty-seventh aspect, the connection wiring is formed by wire bonding.

According to the twenty-eighth aspect, the connection wiring can be easily formed.

A twenty-ninth aspect of the present invention is the ink jet recording head according to the twenty-seventh aspect, wherein the connection wiring is formed of a thin film.

In the twenty-ninth aspect, the connection wiring can be easily formed.

According to a thirtieth aspect of the present invention, in any one of the twenty-seventh to twenty-ninth aspects, the reservoir forming member communicates with the outside through an area corresponding to the piezoelectric element through the reservoir forming member. Wherein the connection wiring is provided through the communication hole.

In the thirtieth aspect, since the connection wiring can be provided in the reservoir forming member, the size of the head can be reduced.

According to a thirty-first aspect of the present invention, in the ink-jet recording head according to the thirtieth aspect, the communication hole is provided in a region of the pressure generating chamber facing the peripheral wall on the reservoir side. It is in.

In the thirty-first aspect, the connection wiring is provided through the communication hole on the reservoir side.

According to a thirty-second aspect of the present invention, in the ink-jet recording method according to the thirtieth aspect, the communication hole is provided in a region facing the peripheral wall of the pressure generating chamber on the nozzle opening side. In the head.

In the thirty-second aspect, the connection wiring is provided through the communication hole on the nozzle opening side.

According to a thirty-third aspect of the present invention, in any one of the twenty-seventh to thirty-second aspects, a driving circuit for driving the piezoelectric element is mounted on the reservoir forming member, and the connection wiring is connected to the driving circuit. An ink jet recording head is connected to a circuit.

In the thirty-third aspect, the drive circuit is mounted on the reservoir forming member, so that space can be saved.

A thirty-fourth aspect of the present invention is the ink-jet recording head according to the thirty-third aspect, wherein the driving circuit is a semiconductor integrated circuit.

In the thirty-fourth aspect, the drive circuit can be easily mounted on the reservoir forming member, and the space can be surely saved.

A thirty-fifth aspect of the present invention is the ink jet recording head according to any one of the first to thirty-fourth aspects, wherein the reservoir forming member is a reservoir forming substrate having the reservoir portion. .

In the thirty-fifth aspect, an ink jet recording head capable of reliably supplying ink to the pressure generating chamber via the reservoir can be easily realized.

A thirty-sixth aspect of the present invention is the ink jet recording head according to the thirty-fifth aspect, wherein a thermal expansion coefficient of the reservoir forming substrate is substantially the same as a thermal expansion coefficient of the flow path forming substrate. It is in.

According to the thirty-sixth aspect, the reservoir forming member and the flow path forming substrate can be bonded at a high temperature, and the manufacturing process can be simplified.

The thirty-seventh aspect of the present invention is a thirty-fifth or thirty-sixth aspect.
Wherein the material of the reservoir forming substrate is selected from the group consisting of silicon, glass, and ceramics.

In the thirty-seventh aspect, the manufacturing process can be reliably simplified by forming the reservoir forming substrate with a specific material.

[0086] A thirty-eighth aspect of the present invention is characterized in that, in any one of the first to thirty-seventh aspects, the nozzle forming member is formed of substantially the same material as the flow path forming substrate and the reservoir forming member. In the ink jet recording head.

In the thirty-eighth aspect, the joining of the nozzle forming member is facilitated, and the manufacturing process can be simplified.

A thirty-ninth aspect of the present invention is the ink jet recording head according to any one of the first to thirty-eighth aspects, wherein the nozzle forming member is a nozzle plate having the nozzle openings. .

In the thirty-ninth aspect, an ink jet recording head that discharges ink from nozzle openings can be easily realized.

In a fortieth aspect of the present invention, in any one of the first to thirty-ninth aspects, the pressure generating chamber is formed on a ceramic substrate, and each layer of the piezoelectric element is formed by pasting or printing a green sheet. The ink jet recording head is characterized in that:

In the fortieth aspect, the head can be easily manufactured.

In a forty-first aspect of the present invention, in any one of the first to forty aspects, the pressure generation chamber is formed on a silicon single crystal substrate by anisotropic etching, and each layer of the piezoelectric element is formed of a thin film and An ink jet recording head characterized by being formed by a method.

In the forty-first mode, an ink jet recording head having high-density nozzle openings can be manufactured in a large amount and relatively easily.

A forty-second aspect of the present invention is an ink jet recording apparatus comprising the ink jet recording head according to any one of the first to forty first aspects.

In the forty-second aspect, it is possible to realize an ink jet recording apparatus in which the structure of the head is simplified and the manufacturing cost is reduced.

[0096]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments.

(Embodiment 1) FIG. 1 is an exploded perspective view showing an ink jet recording head according to Embodiment 1 of the present invention, and FIG. 2 is a plan view and a sectional view of FIG.

As shown in the figure, the flow path forming substrate 10 is made of a silicon single crystal substrate having a plane orientation (110) in this embodiment. As the flow path forming substrate 10, usually 150 to 3
A thickness of about 00 μm is used.
Those having a thickness of about 0 to 280 μm, more preferably about 220 μm are suitable. This is because the arrangement density can be increased while maintaining the rigidity of the partition wall between the adjacent pressure generating chambers.

One surface of the flow path forming substrate 10 is an opening surface, and the other surface is formed with a 1-2 μm-thick elastic film 50 made of silicon dioxide previously formed by thermal oxidation.

On the other hand, the opening surface of the flow path forming substrate 10 is anisotropically etched on a silicon single crystal substrate to
The pressure generating chambers 12 divided by the plurality of partition walls 11 are provided in parallel in the width direction, and on the outside in the longitudinal direction, a common ink chamber of each pressure generating chamber 12 communicates with a reservoir portion of a reservoir forming substrate described later. A communication portion 13 forming a part of the reservoir 100 is formed, and is communicated with one end of each pressure generating chamber 12 in the longitudinal direction via an ink supply path 14.

Here, in the anisotropic etching, when a silicon single crystal substrate is immersed in an alkaline solution such as KOH, the substrate is gradually eroded and the first (111) plane perpendicular to the (110) plane and the first (111) plane A second (1) which forms an angle of about 70 degrees with the (111) plane and forms an angle of about 35 degrees with the (110) plane.
11) plane, and the etching rate of the (111) plane is about 1/1 compared to the etching rate of the (110) plane.
This is performed using the property of being 80.
By such anisotropic etching, two first (11
Precision processing can be performed based on depth processing of a parallelogram formed by the 1) plane and two oblique second (111) planes, and the pressure generating chambers 12 can be arranged at high density. it can.

In this embodiment, the long side of each pressure generating chamber 12 is formed by the first (111) plane, and the short side is formed by the second (111) plane. The pressure generating chamber 12 is provided on the flow path forming substrate 1.
It is formed by etching until it reaches the elastic film 50 almost through 0. Here, the elastic film 50 is
The amount attacked by the alkaline solution for etching the silicon single crystal substrate is extremely small. Each of the ink supply passages 14 communicating with one end of each of the pressure generating chambers 12 is formed shallower than the pressure generating chambers 12 and maintains a constant flow resistance of the ink flowing into the pressure generating chambers 12. That is, the ink supply path 14 is formed by partially etching (half-etching) the silicon single crystal substrate in the thickness direction. Note that the half etching is performed by adjusting the etching time.

On the opening side of the flow path forming substrate 10,
A nozzle plate 16 provided with a nozzle opening 15 communicating with the pressure supply chamber 12 on the side opposite to the ink supply path 14 is fixed via an adhesive, a heat welding film, or the like. The thickness of the nozzle plate 16 is, for example, 0.1 to 1
mm, the coefficient of linear expansion is 300 ° C. or less, for example, 2.5 to
It is made of 4.5 [× 10 ⁻⁶ / ° C.] glass ceramic or non-rusting steel. The nozzle plate 16 entirely covers one surface of the flow path forming substrate 10 on one surface, and also serves as a reinforcing plate for protecting the silicon single crystal substrate from impact and external force. In addition, the nozzle plate 16 is used to
May be formed of a material having substantially the same thermal expansion coefficient as that of the material. In this case, since the deformation of the flow path forming substrate 10 and the nozzle plate 16 due to heat become substantially the same, it is possible to easily join them using a thermosetting adhesive or the like.

Here, the size of the pressure generating chamber 12 for applying the ink droplet ejection pressure to the ink and the size of the nozzle opening 15 for ejecting the ink droplet depend on the amount of the ejected ink droplet, the ejection speed, and the ejection frequency. Optimized. For example,
When recording 360 ink droplets per inch, the nozzle openings 15 need to be formed with a diameter of several tens of μm with high accuracy.

On the other hand, on the elastic film 50 on the side opposite to the opening surface of the flow path forming substrate 10, the thickness is, for example, about 0.2 μm.
A lower electrode film 60, a piezoelectric film 70 having a thickness of, for example, about 1 μm, and an upper electrode film 80 having a thickness of, for example, about 0.1 μm are formed by lamination in a process to be described later.
0. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric film 70, and the upper electrode film 80. Generally, one of the electrodes of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric film 70 are patterned for each pressure generating chamber 12. Here, a portion which is constituted by one of the patterned electrodes and the piezoelectric film 70 and in which a piezoelectric strain is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion 320. In the present embodiment, the lower electrode film 60 is used as a common electrode of the piezoelectric element 300 and the upper electrode film 80 is used as an individual electrode of the piezoelectric element 300. In any case, the piezoelectric active portion is formed for each pressure generating chamber. Also, here
The combination of the piezoelectric element 300 and the vibration plate whose displacement is generated by driving the piezoelectric element 300 is referred to as a piezoelectric actuator. In the example described above, the elastic film 50 and the lower electrode film 6
Although 0 functions as a diaphragm, the lower electrode film may also serve as an elastic film.

The piezoelectric element 300 of the flow path forming substrate 10
On the side, a reservoir forming substrate 20 having a reservoir portion 21 constituting at least a part of the reservoir 100 is joined. In this embodiment, the reservoir portion 21 penetrates the reservoir forming substrate 20 in the thickness direction, and
Each of the pressure generating chambers 12 is communicated with the communicating portion 13 of the flow path forming substrate 10 as described above.
Constitute a reservoir 100 serving as a common ink chamber.

As the reservoir forming substrate 20, it is preferable to use a material having substantially the same thermal expansion coefficient as that of the flow path forming substrate 10, for example, glass, ceramic material, or the like. It was formed using a silicon single crystal substrate of the same material. As a result, as in the case of the nozzle plate 16 described above, the two can be reliably bonded even when they are bonded at a high temperature using a thermosetting adhesive. Therefore, the manufacturing process can be simplified.

Further, the reservoir forming substrate 20 includes:
The compliance substrate 30 including the sealing film 31 and the fixing plate 32 is joined. Here, the sealing film 31 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide (PPS) film having a thickness of 6 μm), and one side of the reservoir 21 is sealed by the sealing film 31. Has been stopped. The fixing plate 32 is made of a hard material such as a metal (for example, stainless steel (SU
S) etc.). The reservoir 10 of the fixing plate 32
Since the region facing 0 is the opening 33 completely removed in the thickness direction, one surface of the reservoir 100 is sealed only with the sealing film 31 having flexibility, and the internal pressure changes. Thus, the flexible portion 22 can be deformed.

Further, an ink introduction port 25 for supplying ink to the reservoir 100 is formed on the compliance substrate 30 substantially outside the central portion in the longitudinal direction of the reservoir 100. Further, the reservoir forming substrate 20 is provided with an ink introduction path 26 that communicates the ink introduction port 25 with the side wall of the reservoir 100. In the present embodiment, the ink is supplied to the reservoir 100 by one ink inlet 25 and the ink inlet path 26. However, the present invention is not limited to this. For example, according to a desired ink supply amount, A plurality of ink introduction ports and ink introduction paths may be provided, or the opening area of the ink introduction ports may be increased to enlarge the ink flow path.

Normally, the reservoir 10 is
When the ink is supplied to 0, a pressure change occurs in the reservoir 100 due to, for example, a flow of the ink when the piezoelectric element 300 is driven or ambient heat. However, as described above, one surface of the reservoir 100 is
1 to form a flexible portion 22
The flexible portion 22 flexes and absorbs the pressure change. Therefore, the inside of the reservoir 100 is always maintained at a constant pressure. The other parts are held by the fixing plate 32 with sufficient strength. In the present embodiment,
Since the number of substrates constituting the reservoir 100 and the like can be reduced, material costs, assembly costs, and the like can be reduced.

On the other hand, the piezoelectric element 3 of the reservoir forming substrate 20
In a region opposed to the piezoelectric element 300, a piezoelectric element holding portion 24 capable of sealing the space is provided with a space that does not hinder the movement of the piezoelectric element 300, and at least the piezoelectric active portion 320 of the piezoelectric element 300 is provided. Are sealed in the piezoelectric element holding portion 24. Note that, in the present embodiment, the piezoelectric element holding section 24 includes a plurality of piezoelectric elements 3 arranged in parallel in the width direction.
It is formed in a size to cover 00.

As described above, the reservoir forming substrate 20 constitutes the reservoir 100 and also serves as a cap member for shutting off the piezoelectric element 300 from the external environment. Can be prevented. In the present embodiment, the piezoelectric element holding unit 2
Although the inside of the piezoelectric element holding part 4 is merely sealed, for example, the inside of the piezoelectric element holding part 24 is kept at a low humidity by evacuating the space inside the piezoelectric element holding part 24 or setting it to a nitrogen or argon atmosphere. The piezoelectric element 30
0 can be more reliably prevented from being destroyed.

In this embodiment, the piezoelectric film 70 and the upper electrode film 80 of the piezoelectric element 300 sealed by the piezoelectric element holding section 24 are connected to the flow path from one end of the pressure generating chamber 12 in the longitudinal direction. An exposed portion 10 extending on the formation substrate 10 to the outside of the reservoir formation substrate 20 and exposing a surface of the flow path formation substrate 10 on the joining side with the reservoir formation substrate
a, an external wiring 4 such as a flexible cable
0 is connected. That is, by extending the wiring from the piezoelectric element 300 to the outside of the reservoir forming substrate 20, the piezoelectric element 300 and the external wiring can be easily connected.

The ink jet recording head of this embodiment takes in ink from the ink inlet 25 connected to an external ink supply means (not shown), and
After filling the inside with ink from 00 to the nozzle opening 15, each lower electrode film 60 corresponding to the pressure generating chamber 12 is made according to a recording signal from an external driving circuit (not shown).
A voltage is applied between the pressure generating chamber 12 and the upper electrode film 80 to deflect and deform the elastic film 50, the lower electrode film 60, and the piezoelectric film 70.
5 ejects ink droplets.

In this embodiment, the piezoelectric element holding portions 24 of the reservoir forming substrate 20 are formed so as to cover all the piezoelectric elements 300 arranged in parallel in the width direction. However, the present invention is not limited to this. For example, as shown in FIG. 3, the piezoelectric element holding portions 24 are formed as independent piezoelectric element holding portions 24A for the respective piezoelectric elements 300 by the partition walls 27, and the piezoelectric elements 300 are sealed in the respective piezoelectric element holding portions 24A. It may be. As a result, the partition walls 27 are respectively joined to portions of the flow path forming substrate 10 corresponding to the side walls 12a of the pressure generating chambers 12, and the rigidity of the peripheral walls of the pressure generating chambers 12 is improved, and the piezoelectric element The fall of the peripheral wall when the 300 is driven can be suppressed. Needless to say, even with such a configuration, it is possible to prevent the piezoelectric element 300 from being broken, as in the above-described embodiment.

In the present embodiment, the piezoelectric film 70 and the upper electrode film 80 are extended to the outside of the reservoir forming substrate 20, and the upper electrode film 80 and the external wiring 40 are connected. Without limitation, for example, as shown in FIG.
Each of the piezoelectric elements 300 is patterned in a region facing the pressure generating chamber 12, and the upper electrode film 80 is separated from the insulator film 85.
The lead electrode 90 is extended to the exposed portion 10a outside the reservoir forming substrate 20 through the external wiring 4 near the end.
0 may be connected.

As described above, the lead electrode 90 is connected to the upper electrode film 8.
By extending from 0 to the outside of the reservoir forming substrate 20 and connecting to the external wiring 40, the gap between the elastic film 50 when the reservoir forming substrate 20 is bonded becomes only a few μm, and the piezoelectric element 300 holds the piezoelectric element. The inside of the portion 24 can be more securely sealed.

In this embodiment, the flow path forming substrate 10
Is formed to be larger than the reservoir forming substrate 20, and the connection between the piezoelectric element 300 and the external wiring 40 is performed on the exposed portion 10a of the flow path forming substrate 10. However, the present invention is not limited to this. As shown in FIG. 5, the reservoir forming substrate 2
0 is formed to be larger than the flow path forming substrate 10 to form an exposed portion 20a that exposes the surface of the reservoir forming substrate 20 on the joint side with the flow path forming substrate 10. On the exposed portion 20a, the piezoelectric element 300 and the outside are formed. You may make it connect with wiring.

Further, in this embodiment, the flow path forming substrate 1
On the other end side of the zero pressure generation chamber 12 opposite to the nozzle opening 15, the communication portion 13 forming a part of the reservoir 100 is provided via the ink supply path 14. However, the present invention is not limited to this. For example, as shown in FIG. 6, the reservoir 100 is basically composed of only the reservoir section 21 of the reservoir forming substrate 20, and each pressure generating chamber 1 is formed in the flow path forming substrate 10.
The reservoir 2 and the reservoir 100 may be communicated with each other through a communication passage 18 having a narrower flow path than the reservoir 100. With such a configuration, when the ink is supplied to the pressure generating chamber 12, the flow velocity of the ink is maintained, so that the incorporation of bubbles can be prevented and good ink ejection can be performed.

(Embodiment 2) FIG. 7 is a sectional view of an ink jet recording head according to Embodiment 2.

In this embodiment, the flexible portion 22 is connected to the reservoir 2
This is an example in which the first flow path forming substrate 10 is provided on the flow path forming substrate 10 side, not in the area on the opposite side.

More specifically, as shown in FIG. 7, in the present embodiment, the flow path forming substrate 1 in an area corresponding to the reservoir 21 is provided.
0, a penetrating portion 18 that is not communicated with the pressure generating chamber 12 is provided over the width direction of the pressure generating chamber 12, and at least between the penetrating portion 18 and the reservoir portion 21 in the thickness direction. The flexible portion 22 is closed by a flexible film 110 that can be elastically deformed.

On the other hand, a fixing plate 32A made of a hard material such as metal, for example, stainless steel (SUS) is joined to the surface of the reservoir forming substrate 20 opposite to the flow path forming substrate 10, and One side is sealed.

As in the case of the above-described flexible portion 22, such a flexible film 110 elastically deforms when a pressure change occurs in the reservoir 100 due to driving of the piezoelectric element 300 or the like. Absorb. Thereby, the internal pressure of the reservoir 100 is always suppressed to a certain value or less, and the ink ejection characteristics are favorably maintained.

In this embodiment, the elastic film 50 and the lower electrode film 60, the piezoelectric film 70, and the upper electrode film 80 constituting the piezoelectric element 300 are formed on the flow path forming substrate 10 in the region corresponding to the reservoir section 21. These films are provided as flexible films 110 in a region facing the penetrating portion 18. The thickness of the flexible film 110 having such a film configuration is about 3
It is about μm and sufficiently functions as a compliance part.

It is preferable that such a flexible film 110 includes a film having a tensile stress in all plane directions. In particular, it is preferable that the stress of the entire film constituting the flexible film 110 is strong in the tensile direction and the flexible film 110 does not buckle. Thereby, excessive deformation of the flexible film 110 is suppressed, and breakage of the flexible film 110 can be prevented.

In the present embodiment, the flexible film 110 is composed of only the elastic film 50 and the film constituting the piezoelectric element 300, and can be formed together with the formation of the piezoelectric element 300. Further, the through portion 18 can be formed by etching together with the pressure generating chamber 12, so that it can be easily formed without increasing the number of manufacturing steps.

In the present embodiment, the flexible film 110 includes the elastic film 50, the lower electrode film 60, the piezoelectric film 70, and the upper electrode film 80, but is not limited thereto. And at least one layer constituting the piezoelectric element 300. In any case, any film may be used as long as it is flexible and has a predetermined strength. However,
When the elastic film is formed of silicon dioxide as in the present embodiment, it is not preferable to use only the elastic film because the strength is low. Needless to say, a film made of another material may be separately provided as the flexible film 110.

(Embodiment 3) FIG. 8 is a sectional view of a main part of an ink jet recording head according to Embodiment 3 and a schematic view of a flexible film.

In the present embodiment, as shown in FIG. 8, the surface of the flexible film 110 to be the flexible portion 22 on the channel forming substrate side is
The second embodiment is the same as the second embodiment except that a beam 111 made of a ridge extending in the plane direction is provided.

The beam portion 111 serves to increase the strength of the flexible film 110. For example, in the present embodiment, the beam portion 111 is provided as shown in FIG.
As shown in (b), the flexible film 110 is provided in a grid over the entire surface. The area of the beam 111 is
What is necessary is just to determine suitably according to conditions, such as a material and film thickness of the flexible film 110, so that desired strength may be obtained. At this time, in order to surely absorb the pressure change in the reservoir 100, the actual flexible portion of the flexible film 110 where the beam portion 111 is not formed is at least about 10 times the pressure generating chamber. Is preferably maintained.

The method of forming the beam portion 111 is not particularly limited. For example, when forming the penetrating portion 18 in the flow path forming substrate 10, the flow path is formed by etching using a predetermined mask pattern. A portion where a part of the formation substrate 10 remains may be the beam portion 111.

As described above, the beam portion 111 is formed on the flexible film 110.
Is provided, the strength of the flexible film 110 can be increased. Therefore, by adjusting the area of the beam portion 111, the strength and compliance of the flexible film 110 can be easily and accurately adjusted.

The shape of the beam portion 111 is not limited to the lattice shape, but may be any other shape such as an oblique lattice as long as it has a predetermined strength and can maintain a predetermined compliance. Good. Also, of course, the strength and compliance of the flexible film 110 may be adjusted by changing the size of the penetrating portion 18.

(Embodiment 4) FIG. 9 is a plan view and a sectional view of an ink jet recording head according to Embodiment 2.

As shown in FIG. 9, the present embodiment is similar to the first embodiment except that a reservoir portion 21 constituting a part of the reservoir 100 is provided with a reinforcing portion 28 for maintaining the rigidity of the reservoir forming substrate 20. Is the same as

That is, in this embodiment, the reservoir portion 21 is defined on the reservoir forming substrate 20 and at least one reinforcing portion 28, for example, in this embodiment, two beam-like reinforcing portions are provided between the opposing side walls. A part 28 is provided. The reinforcing portion 28 is formed along the longitudinal direction of the piezoelectric element 300 on the surface of the reservoir portion 21 opposite to the joint surface with the flow path forming substrate 10. Also, this reinforcing portion 28
It is formed by half-etching the reservoir forming substrate 20 from the joint surface side with the flow path forming substrate 10, and has a thickness smaller than other portions. Such a reinforcing portion 28
It is preferable that the area be as large as possible within a range in which the flexible portion 22 can maintain the internal pressure of the reservoir 100 uniformly.

As described above, in the present embodiment, the reservoir 10
0 is provided between the side walls defining 0, and the rigidity of the reservoir 21 is improved.
Even if the volume of the substrate is relatively large, deformation such as warpage of the reservoir forming substrate due to thermal stress during mounting can be prevented,
Cracking of the reservoir forming substrate caused by this deformation can be prevented. Therefore, the durability and reliability of the head can be improved.

In the present embodiment, the reinforcing portion 28 is provided on the surface of the reservoir forming substrate 20 opposite to the joining surface of the flow path forming substrate 10, but the present invention is not limited to this. As shown in (2), the reservoir forming substrate 20 may be provided on the joint surface side with the flow path forming substrate 10.

Further, in the present embodiment, the entire reinforcing portion 28 is formed thinner than the other portions. However, the present invention is not limited to this. For example, as shown in FIG. It may be formed to have the same thickness as the reservoir forming substrate 20, and a part on the bonding surface side with the flow path forming substrate 10 may be a removed part 28 a from which a part in the thickness direction is removed. With such a structure, the strength of the reservoir forming substrate 20 can be further improved without lowering the function of the reservoir 100, and deformation due to heat during mounting can be reliably prevented.

Further, in this embodiment, the two reinforcing portions 2
8 is provided, but is not limited to this. For example,
One or three or more may be provided. In any case, the shape of the reinforcing portion 28 may be any shape as long as the compliance of the flexible portion 22 can be maintained to the extent that the internal pressure change of the reservoir 100 can be absorbed.

(Embodiment 5) FIG. 12 is a sectional view of an essential part of an ink jet recording head according to Embodiment 5.

The present embodiment is an example in which a compliance substrate 30A composed of one member is provided on the flow path forming substrate 10. That is, in the present embodiment, as shown in FIG. 12, a part of the region facing the reservoir 100 in the thickness direction is removed to form a flexible portion 22A having flexibility, and the ink introduction port 25 is provided outside the flexible portion 22A. This is the same as Embodiment 1 except that a through hole is formed. The material of the compliance substrate 30A is preferably a flexible resin material such as a fluororesin, a silicone-based resin, or a silicone rubber, so that the compliance substrate 30A can be easily formed. it can.

The method of manufacturing the compliance substrate 30A is not particularly limited. For example, a resin layer having a predetermined thickness is formed on a silicon single crystal substrate constituting the reservoir forming substrate 20, and then the reservoir forming substrate 20 is formed. The reservoir 100 and the like can be formed by etching or the like, and further, a part of the region of the resin layer facing the reservoir 100 in the thickness direction can be etched.

Further, in this embodiment, the compliance substrate 30A is formed of a resin material. However, the present invention is not limited to this. For example, as shown in FIG. It may be made of a thin film of metal or ceramic of about 10 to 10 μm. In this case, the region facing the reservoir 100 can be a flexible portion 22B having flexibility without removing a part in the thickness direction. Therefore, the head can be manufactured more easily.

(Embodiment 6) FIG. 14 is a sectional view of a principal part of an ink jet recording head according to Embodiment 6.

In the present embodiment, as shown in FIG. 6, the piezoelectric element 300 extends in the column direction of the pressure generating chambers 12 in a portion of the reservoir forming substrate 20 corresponding to the piezoelectric element 300 in a region facing the piezoelectric element holding portion 24. The third embodiment is the same as the first embodiment except that a detection through hole 24a for detecting the displacement of 300 is provided.

In such a configuration, the reservoir forming substrate 2
Before bonding the compliance substrate 30 on the zero, the displacement of the piezoelectric element 300 can be checked using, for example, a laser or the like. Therefore, a defect of the piezoelectric element 300 can be found before the head is completed, and the manufacturing efficiency can be improved. Also, this detection through-hole 24a
Is sealed by the compliance substrate 30, the piezoelectric element holding portion 24 can be held in a sealed state as in the first embodiment.

The size of the detection through-hole 24 a is not particularly limited, as long as it is formed at least in a region facing the piezoelectric element 300. Therefore, in the present embodiment, the pressure generating chambers 12 are provided in a groove shape in the row direction. However, for example, the pressure generating chambers 12 may be formed as round holes for each piezoelectric element 300, or the entire piezoelectric element holding portion may be formed as a through hole. Good.

In this embodiment, the detection through-hole 24
a is sealed with the compliance substrate 30, but is not limited to this. For example, as shown in FIG. 15, the detection through-hole 24a is sealed only with the sealing film 31 having flexibility, that is, Fixed plate 3 in a region facing detection through-hole 24a
2 may be removed to form a flexible portion 22C. Accordingly, when a pressure change occurs in the piezoelectric element holding portion 24, the pressure change is absorbed by the deformation of the flexible portion 22C, and the inside of the piezoelectric element holding portion 24 can be constantly maintained at a constant pressure.

The flexible portion 22C of the piezoelectric element holding portion 24
The sealing film 31 may be formed of, for example, a light-transmitting member such as an acrylic resin, so that displacement can be detected while the piezoelectric element 300 is sealed in the piezoelectric element holding portion 24. it can. That is, the inspection of the piezoelectric element 300 can be always performed.

(Embodiment 7) FIG. 16 is a plan view and a sectional view of an ink jet recording head according to Embodiment 7.

The present embodiment is another example of the wiring method of the piezoelectric element 300. As shown in FIG. 16, a compliance substrate 30 is provided on a part of the reservoir forming substrate 20 on the side opposite to the reservoir 100. The exposed portion 20b is not exposed and the surface of the reservoir forming substrate 20 is exposed. Then, the wiring 29 is formed by wire bonding from the upper electrode film 80 of the piezoelectric element 300 extended to the outside of the reservoir forming substrate 20 to the exposed portion 2 of the reservoir forming substrate 20.
0b, and the end of the extended wiring 29 is connected to the mounting portion 120 for connecting the piezoelectric element 300 and the external wiring 40.
And Further, the structure is the same as that of the first embodiment, except that the outside is molded by an insulating member 95 such as epoxy to achieve electrical insulation.

Here, as in the conventional case, the flow path forming substrate 10
When connecting the piezoelectric element 300 and the external wiring 40 on the exposed portion where the surface of the exposed portion is exposed, the width of the exposed portion is about 2.2.
Approximately 3 mm is required, and the size of the head is slightly increased. On the other hand, in the present embodiment, the wiring 29 is extended from the exposed portion 10a of the flow path forming substrate 10 to the exposed portion 20b of the reservoir forming substrate 20 by wire bonding, and is connected to the external wiring 40. So
The width of the exposed portion 10a of the flow path forming substrate 10 can be set to about 0.2 mm, and the size of the recording head can be further reduced. Further, needless to say, the same effect as in the first embodiment can be obtained by such a configuration.

(Eighth Embodiment) FIG. 17 is a plan view and a sectional view of an ink jet recording head according to an eighth embodiment.

This embodiment is an example in which a through-groove is provided in the reservoir forming substrate 20, and the piezoelectric element 300 and an external wiring are connected through the through-groove. More specifically, as shown in FIG. 17, in the present embodiment, the piezoelectric film 70 of the piezoelectric element 300 is used.
In addition, the upper electrode film 80 is extended to the longitudinal peripheral wall of the pressure generating chamber 12 on the nozzle opening 15 side, and is sandwiched between the flow path forming substrate 10 and the reservoir forming substrate 20. Further, similarly to the seventh embodiment, a part of the joint surface of the reservoir forming substrate 20 with the compliance substrate 30 is an exposed portion 20b whose surface is exposed, and corresponds to the exposed portion 20b and the piezoelectric element 300 is formed. In a region facing the upper electrode film 80, the through-groove 3 extending in the direction in which the pressure generating chambers 12 are arranged in parallel is formed.
5 are formed. Then, a wire 29 is extended from the upper electrode film 80 of each piezoelectric element 300 through the through groove 35 to the surface of the reservoir forming substrate 20 by wire bonding, and an end of the wire 29 is connected to the piezoelectric element 300 and a flexible cable or the like. The mounting section 120 connects to the external wiring 40.

In such a configuration, since the wiring 29 extends through the through groove 35, the above-described flow path forming substrate 10
Alternatively, there is no need to provide the exposed portions 10a and 20a of the reservoir forming substrate 20, and the head can be further reduced in size.

In the present embodiment, the through-groove 35 is formed in a groove shape over the rows of the pressure generating chambers 12, but is not limited to this. For example, the through-groove 35 is independent for each piezoelectric element 300. A through hole may be provided.

In the present embodiment, the wiring 29 is extended from the upper electrode film 80 by wire bonding. However, the present invention is not limited to this. For example, as shown in FIG. 18, for example, gold (Au) The conductive thin film such as
The wiring 29 </ b> A may be formed by forming a film on the inner peripheral surface and the upper surface of the compliance substrate 30 and patterning this conductive thin film for each piezoelectric element 300.

Further, for example, as shown in FIG. 19, the wiring 29B is connected to the exposed portion 20b of the reservoir forming substrate 20 through the joining surface 20c and the outer surface 20d of the reservoir forming substrate 20.
The mounting portion 120 may be extended to the end, and the end thereof may be connected to the external wiring 40. When such a wiring 29B is provided, a lead electrode 90 is extended from the upper electrode film 80 to the bonding surface 20c of the reservoir forming substrate 20 as shown in FIG. It is preferable to join the wiring 80 and the wiring 29B. As a result, the gap between the elastic film 50 and the reservoir forming substrate 20 when the reservoir forming substrate 20 is adhered becomes only a few μm, and the piezoelectric element 300 can be more securely sealed in the piezoelectric element holding portion 24 as described above.

(Embodiment 9) FIGS. 20A and 20B are a plan view and a sectional view of a main part of an ink jet recording head according to Embodiment 9. FIG.

In the present embodiment, as shown in FIG. 20, the flow path forming substrate 10 is provided with two rows in which the pressure generating chambers 12 are arranged in the width direction so that the ends on the nozzle opening 15 side face each other. The piezoelectric element 300 is formed in a region corresponding to each pressure generating chamber 12. In addition, reservoirs 100 are provided in each of the rows of the pressure generating chambers on the outside of the pressure generating chambers 12 in the longitudinal direction, and the ink introduction ports 25 and the ink introduction paths 26 communicate with the reservoirs 100, respectively. ing. The structures of the reservoir, the ink inlet, and the like are the same as in the above-described embodiment.

Each of the piezoelectric elements 300 extends from the region facing the pressure generating chamber 12 to the peripheral wall on the reservoir 100 side, and the flow path forming substrate 10 and the reservoir forming substrate 2
0. Further, the reservoir forming substrate 2
In the area facing the upper electrode film 80 of the piezoelectric element 300 on the side of the reservoir section 21 of the pressure generating chamber 12, that is, the area facing the peripheral wall of the pressure generating chamber 12, as in the eighth embodiment,
A through groove 35 is provided for each row. Further, the reservoir forming substrate 20 in a region corresponding to the space between the rows of the pressure generating chambers 12 is formed.
On the upper side, for example, a drive circuit 130 for driving the piezoelectric element 300 is mounted. This drive circuit 130
A semiconductor integrated circuit (I) including a circuit board or a driving circuit
C). The upper electrode film 80 and the drive circuit 130 of each piezoelectric element 300 are respectively connected to the wiring 2 extended by wire bonding or the like via the through groove 35.
9. Further, a wiring 29D for supplying a signal to the driving circuit 130 is provided on the reservoir forming substrate 20, and one end of the wiring 29D is connected to the driving circuit 130, and the other end is connected to the external wiring 40. Mounting section 120.

With such a configuration, the head can be reduced in size as in the eighth embodiment. Further, in the present embodiment, since the through groove 35 is provided on the reservoir 100 side, the piezoelectric element 300 and the drive circuit 130 and the like can be more efficiently connected between the plurality of rows of the pressure generating chambers 12. it can.

In the present embodiment, the drive circuit 130 is provided on the reservoir forming substrate 20. However, the present invention is not limited to this. For example, as in the first embodiment,
Needless to say, the wiring extending from the piezoelectric element 300 and the external wiring such as a flexible cable may be connected on the exposed portion 10a of zero.

In the present embodiment, the upper electrode film 80 of the piezoelectric element 300 and the drive circuit 130 are connected by the wiring 29 extended only by wire bonding. However, the present invention is not limited to this. As shown in FIG.
Driving circuit 120 and through groove 35 on reservoir forming substrate 20
An IC wiring section 140 made of a thin film may be provided in a region between the piezoelectric element 300 and the driving circuit 130 via the IC wiring section 140. That is, the wiring 2 is formed by wire bonding from the upper electrode film 80 of each piezoelectric element 300 to one end of the IC wiring section 140.
9E may be extended, and the drive circuit 130 may be connected to the other end of the IC wiring section 140 by wire bonding. Further, the wiring 29E is extended from the upper electrode film 80 to the IC wiring part 140 by wire bonding, but is not limited to this. For example, as shown in FIG. 22, for example, a conductive material such as gold (Au) is used. Through thin film 3
The wiring 29 </ b> E may be formed by forming a film on the inner peripheral surface of the substrate 5 and the upper surface of the reservoir forming substrate 20 and patterning the conductive thin film for each piezoelectric element 300.

(Embodiment 10) FIG.
3A and 3B are a plan view and a cross-sectional view of a main part of the inkjet head according to the first embodiment.

In the present embodiment, as shown in FIG. 23, the mounting portion 120 is provided on the exposed portion 10b on one end side of the flow path forming substrate 10 in the direction in which the piezoelectric elements 300 are arranged.

That is, in this embodiment, the piezoelectric element 30
0 is provided in a region facing the pressure generating chamber 12, and the lead electrode 90 extends from the upper electrode film 80 to a region facing the bonding surface 20 c of the reservoir forming substrate 20. Also,
Wiring 29F is provided on the joint surface 20c of the reservoir forming substrate 20 and the inner surface 20e of the piezoelectric element holding portion 24,
It is the same as the first embodiment except that the lead electrode 90 and the mounting section 120 are connected.

The route of the wiring 29F is not particularly limited. When the reservoir forming substrate 20 is bonded with an adhesive or the like, the wiring 29F and the ends of the lead electrodes 90 and the mounting portion 1
What is necessary is just to connect with one end of 20.

In such a configuration, since the external wiring 40 can be pulled out from one end of the pressure generating chamber 12 in the width direction, the heads can be arranged side by side. Further, needless to say, the same effects as those of the above-described embodiment can be obtained.

(Other Embodiments) The embodiments of the present invention have been described above, but the basic configuration of the ink jet recording head is not limited to the above.

For example, in the above-described embodiment, the reservoir forming substrate 20 having the reservoir portion 21 constituting a part of the reservoir 100 as the reservoir forming member is joined to one surface of the flow path forming substrate 10. However, the present invention is not limited to this. For example, the reservoir forming member may have a structure in which a reservoir is formed by a plurality of substrates.

Similarly, the nozzle plate 16 is joined as a nozzle forming member. However, the present invention is not limited to this. For example, another substrate having a nozzle communication hole or the like communicating the nozzle opening with the pressure generating chamber may be used. May be used as a multilayer structure.

In each of the above embodiments, a thin-film type ink jet recording head manufactured by applying a film forming and lithography process has been described as an example. However, the present invention is not limited to this. The present invention can also be applied to a thick-film type ink jet recording head formed by a method such as attaching a sheet.

The ink jet recording head of each of these embodiments constitutes a part of a recording head unit having an ink flow path communicating with an ink cartridge or the like, and is mounted on an ink jet recording apparatus. FIG.
FIG. 1 is a schematic view showing an example of the ink jet recording apparatus.

As shown in FIG. 24, the recording head units 1A and 1B having the ink jet recording heads
Cartridges 2A and 2B constituting ink supply means are detachably provided. A carriage 3 on which the recording head units 1A and 1B are mounted is provided on a carriage shaft 5 attached to the apparatus main body 4 so as to be movable in the axial direction. I have. The recording head units 1A and 1B are, for example,
Each of them ejects a black ink composition and a color ink composition.

The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and a timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted moves along the carriage shaft 5. Moved. On the other hand, a platen 8 is provided on the apparatus main body 4 along the carriage shaft 5, and a recording sheet S, which is a recording medium such as paper fed by a paper feed roller (not shown), is wound around the platen 8. It is designed to be transported.

[0179]

As described above, according to the present invention, the reservoir is formed by joining the reservoir forming substrate constituting at least a part of the reservoir on the flow path forming substrate. Simplification can be achieved, and the number of manufacturing steps can be reduced and the manufacturing cost can be improved. In addition, since the reservoir forming substrate also functions as a cap member that blocks the piezoelectric element from the outside, it is possible to prevent the piezoelectric element from being broken due to an external environment, and to improve durability. Further, by connecting the piezoelectric element and the external wiring on the reservoir forming substrate, there is an effect that the head can be reduced in size.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an ink jet recording head according to a first embodiment of the present invention.

FIG. 2 is a plan view and a cross-sectional view of the inkjet recording head according to the first embodiment of the present invention.

FIG. 3 is a plan view and a cross-sectional view illustrating a modification of the ink jet recording head according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a modification of the ink jet recording head according to the first embodiment of the present invention.

FIG. 5 is a sectional view showing a modified example of the ink jet recording head according to the first embodiment of the present invention.

FIG. 6 is a plan view and a cross-sectional view illustrating a modification of the ink jet recording head according to the first embodiment of the present invention.

FIG. 7 is a plan view and a cross-sectional view of an ink jet recording head according to Embodiment 2 of the present invention.

FIG. 8 is a plan view of an ink jet recording head and a schematic diagram of a flexible film according to a third embodiment of the present invention.

FIG. 9 is a plan view and a cross-sectional view of an ink jet recording head according to Embodiment 4 of the present invention.

FIG. 10 is a perspective view showing a modification of the ink jet recording head according to Embodiment 4 of the present invention.

FIG. 11 is a perspective view showing a modification of the ink jet recording head according to Embodiment 4 of the present invention.

FIG. 12 is a sectional view of an ink jet recording head according to Embodiment 5 of the present invention.

FIG. 13 is a cross-sectional view showing a modification of the ink jet recording head according to Embodiment 5 of the present invention.

FIG. 14 is a plan view and a cross-sectional view of an inkjet recording head according to Embodiment 6 of the present invention.

FIG. 15 is a sectional view showing a modified example of the ink jet recording head according to Embodiment 6 of the present invention.

FIG. 16 is a plan view and a cross-sectional view of an ink jet recording head according to Embodiment 7 of the present invention.

FIG. 17 is a plan view and a cross-sectional view of an ink jet recording head according to Embodiment 8 of the present invention.

FIG. 18 is a plan view and a cross-sectional view illustrating a modified example of the ink jet recording head according to Embodiment 8 of the present invention.

FIGS. 19A and 19B are a plan view and a cross-sectional view illustrating a modification of the ink jet recording head according to Embodiment 8 of the present invention.

FIG. 20 is a plan view and a cross-sectional view of an ink jet recording head according to Embodiment 9 of the present invention.

FIG. 21 is a sectional view showing a modified example of the ink jet recording head according to Embodiment 9 of the present invention.

FIG. 22 is a sectional view showing a modification of the ink jet recording head according to Embodiment 9 of the present invention.

FIG. 23 is a plan view and a sectional view of an ink jet recording head according to Embodiment 10 of the present invention.

FIG. 24 is a schematic view of an ink jet recording apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 flow path forming substrate 12 pressure generating chamber 13 communication part 14 ink supply path 15 nozzle opening 16 nozzle plate 20 reservoir forming substrate 21 reservoir part 22 flexible part 24 piezoelectric element holding part 30, 30A compliance substrate 31 sealing film 32 fixing plate Reference Signs List 60 lower electrode film 70 piezoelectric film 80 upper electrode film 100 reservoir 300 piezoelectric element

 ──────────────────────────────────────────────────続 き Continued on the front page (31) Priority claim number Japanese Patent Application No. 11-34592 (32) Priority date February 12, 1999 (Feb. 12, 1999) (33) Priority claim country Japan (JP) (72) Inventor Yutaka Furuhata 3-3-5 Yamato, Suwa-shi, Nagano F-term in Seiko Epson Corporation (reference) 2C056 EA21 EA23 FA04 2C057 AF34 AF65 AF93 AG12 AG44 AG85 AP02 AP25 AP34 AQ02 BA04 BA14

Claims (42)

[Claims] A nozzle forming member having a plurality of nozzle openings for discharging ink; a flow passage forming substrate joined to the nozzle forming member and defining a pressure generating chamber communicating with the nozzle openings, respectively; A piezoelectric element provided via a vibration plate on a surface of the flow path forming substrate opposite to the surface to which the nozzle forming member is bonded, and a piezoelectric element for changing a volume of the pressure generating chamber; Forming a reservoir on the surface of the flow path forming substrate on which the piezoelectric element is formed, the reservoir having at least a part of a reservoir that communicates with the pressure generating chamber and supplies ink to each pressure generating chamber. The ink is characterized in that the member is joined, and the reservoir forming member has a piezoelectric element holding portion that seals the space with a space secured in a region facing the piezoelectric element. Jet type recording head. 2. The ink jet recording apparatus according to claim 1, wherein the piezoelectric element holding section is partitioned by partition walls for each piezoelectric element, and the partition walls are joined to the flow path forming substrate. head. 3. The flow channel forming substrate according to claim 1, further comprising a communicating portion communicating with the reservoir portion of the reservoir forming member and forming a part of the reservoir together with the reservoir portion. Inkjet recording head. 4. The pressure sensor according to claim 1, wherein the reservoir and each of the pressure generating chambers are connected to each other via an ink supply path having a flow path relatively narrower than the reservoir. Inkjet recording head. 5. The ink supply device according to claim 1, wherein the reservoir portion of the reservoir forming member is connected to an ink introduction port for supplying ink to the reservoir by communicating with the outside. Characteristic inkjet recording head. 6. The ink jet recording head according to claim 1, wherein the reservoir is formed in a width direction of the plurality of pressure generating chambers arranged in parallel. 7. The ink jet recording head according to claim 1, wherein a part of the reservoir portion of the reservoir forming member has a flexible portion having flexibility. 8. The flow path forming substrate according to claim 7, wherein the flow path forming substrate in a region corresponding to the reservoir section is provided with a penetrating part penetrating without communicating with the pressure generating chamber. An ink jet recording head, wherein the space between the recording head and the recording head is the flexible part. 9. The ink jet recording head according to claim 8, wherein the penetrating portion is formed over a width direction of the plurality of pressure generating chambers arranged in parallel. 10. The ink jet recording head according to claim 8, wherein the penetrating portion is formed by etching together with the pressure generating chamber. 11. The ink jet recording head according to claim 7, wherein the flexible portion is provided by joining a flexible member. 12. An ink jet recording head according to claim 11, wherein said flexible member is made of a metal or ceramic thin film. 13. The ink jet recording head according to claim 11, wherein the flexible member is made of a resin material. 14. The ink jet recording head according to claim 13, wherein the resin material is selected from the group consisting of a fluororesin, a silicone resin and a silicone rubber. 15. The ink jet recording head according to claim 11, wherein the flexible member includes a layer having a tensile stress. 16. The ink jet recording head according to claim 11, wherein the flexible member has only a film constituting the vibration plate and the piezoelectric element. 17. The method according to claim 11, wherein
An ink jet recording head, characterized in that another substrate having a through hole is joined to the flexible member at least in a region facing the flexible portion. 18. The method according to claim 11, wherein
An ink jet recording head, wherein a beam portion formed of a ridge extending in a surface direction is provided on a surface of the flexible member opposite to the reservoir portion. 19. An ink jet recording head according to claim 18, wherein said beam portions are formed in a lattice shape. 20. The reinforcing member according to claim 1, wherein the reservoir portion of the reservoir forming member has at least one beam-like reinforcing portion extending between the opposing side walls that define the reservoir portion. An ink jet recording head, comprising: 21. The ink jet recording head according to claim 20, wherein at least a part of the reinforcing portion is thinner than another portion of the reservoir forming member. 22. The method according to claim 21, wherein the reinforcing portion comprises:
An ink jet recording head, wherein at least a part of the flow path forming substrate side is removed and the thickness is thinner than other parts. 23. The method according to claim 20, wherein
The ink-jet recording head according to claim 1, wherein the reinforcing portion is formed along a longitudinal direction of the piezoelectric element. 24. The sensor according to claim 1, wherein at least a part of a region of the reservoir forming member facing the piezoelectric element is provided with a detection through hole for detecting a displacement of the piezoelectric element. An ink jet recording head. 25. The piezoelectric device according to claim 24, wherein the piezoelectric element holding portion is provided so as to penetrate the reservoir forming member, is sealed with a transparent member, and also serves as the detection through hole. Inkjet recording head. 26. The ink jet recording head according to claim 25, wherein the transparent member forms the flexible portion. 27. The wiring according to claim 1, wherein the wiring on the flow path forming substrate drawn from the piezoelectric element is provided in a region of the reservoir forming member opposite to the flow path forming substrate. An ink jet recording head, comprising: a connection wiring for connecting the wiring provided with the wiring; and an external wiring connected to the wiring provided in a region on the opposite side of the reservoir forming member. 28. An ink jet recording head according to claim 27, wherein said connection wiring is formed by wire bonding. 29. An ink jet recording head according to claim 27, wherein said connection wiring is formed of a thin film. 30. The method according to claim 27, wherein
In the reservoir forming member, in a region corresponding to the piezoelectric element, a communication hole that penetrates the reservoir forming member and communicates with the outside is provided, and the connection wiring is provided through the communication hole. Characteristic inkjet recording head. 31. The ink jet recording head according to claim 30, wherein the communication hole is provided in a region of the pressure generating chamber facing the peripheral wall on the reservoir side. 32. The ink jet recording head according to claim 30, wherein the communication hole is provided in a region facing the peripheral wall of the pressure generating chamber on the nozzle opening side. 33. The method according to claim 27, wherein
A drive circuit for driving the piezoelectric element is mounted on the reservoir forming member, and the connection wiring is connected to the drive circuit. 34. An ink jet recording head according to claim 33, wherein said drive circuit is a semiconductor integrated circuit. 35. The ink jet recording head according to claim 1, wherein the reservoir forming member is a reservoir forming substrate having the reservoir portion. 36. The ink jet recording head according to claim 35, wherein a thermal expansion coefficient of the reservoir forming substrate is substantially equal to a thermal expansion coefficient of the flow path forming substrate. 37. The ink jet recording head according to claim 35, wherein a material of the reservoir forming substrate is selected from the group consisting of silicon, glass and ceramics. 38. The ink jet recording head according to claim 1, wherein the nozzle forming member is formed of substantially the same material as the channel forming substrate and the reservoir forming member. 39. The ink jet recording head according to claim 1, wherein the nozzle forming member is a nozzle plate having the nozzle openings. 40. The ink jet printer according to claim 1, wherein the pressure generating chamber is formed on a ceramic substrate, and each layer of the piezoelectric element is formed by pasting or printing a green sheet. Type recording head. 41. The pressure generating chamber according to claim 1, wherein the pressure generating chamber is formed on a silicon single crystal substrate by anisotropic etching, and each layer of the piezoelectric element is formed by a thin film and a lithography method. An ink jet recording head, characterized in that: 42. An ink jet recording apparatus comprising the ink jet recording head according to claim 1.