JP2019104181A - Liquid discharge head, liquid discharge unit and device for discharging liquid - Google Patents

Abstract

To provide a liquid discharge head capable of preventing entry of a moisture from an adhesive on a junction and having high environment resistance and durability.SOLUTION: A liquid discharge head is configured so that, an actuator, an actuator board comprising a liquid chamber having a longitudinal direction and a short direction to a plane direction of the board on an opposite side of the actuator, and a support board having a recess which is a drive region of the actuator on a surface facing the actuator board, are jointed by an adhesive. A non-formation part of the recess in the support board is a junction wall jointed to the actuator board, the junction wall is arranged in the short direction of the liquid chamber, and a moisture resistance film is formed so as to cover a portion where the adhesive jointing the junction wall of the end in the short direction and the actuator board is exposed and where is outside of the end of the short direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a liquid discharge head, a liquid discharge unit, and an apparatus for discharging a liquid.

  Conventionally, an ink jet head and a recording apparatus equipped with an ink jet head are known which generate pressure fluctuation in a liquid chamber (also referred to as an individual liquid chamber or a pressurized liquid chamber) and eject a liquid from a minute nozzle formed in the liquid chamber. It is done. In such an inkjet head and recording apparatus, thin film PZT (lead zirconate titanate) is used as a piezoelectric material of an actuator that generates pressure fluctuation, and development in the industrial field is progressing in recent years.

  On the other hand, thin film PZT, wiring metal (for example, aluminum) and the like are vulnerable to moisture, and high durability and environmental resistance are required. In addition, Pt, which is generally used for an electrode, has a high catalytic action, so it changes moisture into an active state such as hydrogen radicals and causes corrosion of the oxide piezoelectric material. When such a phenomenon progresses, discharge between the electrodes, peeling of the electrodes and the piezoelectric body, or the like may occur.

  As described above, the actuator is required to have high durability and environmental resistance, and covering the actuator with a moisture resistant barrier film is performed as one of means for satisfying the requirements. However, if the actuator is covered with a moisture-resistant barrier film, the actuator may be pulled by the barrier film when it is driven, which may inhibit the driving of the actuator. In addition, since the barrier film is pulled when the actuator is driven, the density of the barrier film is substantially reduced, so that a sufficient humidity barrier effect can not be obtained in long-term use required for industrial use.

  In the above-described ink jet head and recording apparatus, the strength of the actuator substrate is increased, and the support substrate is bonded to the actuator substrate in order to seal the actuator driver. Here, both substrates are bonded by an adhesive, but it is difficult to adopt an adhesive having sufficient sealability to moisture from the adhesive property of adhesive, viscosity, wettability to substrate, filler size, etc. . Therefore, moisture intrudes into the space where the actuator exists from the bonding interface of the substrate, and the above-mentioned problems such as discharge between the electrodes occur. In particular, the ink jet head and the recording apparatus become noticeable when used in a high temperature and high humidity environment.

  From such a thing, if it is used in the state where sealability to moisture is not secured sufficiently, it will fail before driving for a desired time, and the problem that required environmental resistance and durability can not be secured There was a point. With regard to these, for example, the following proposals have been made, but the problems have not been solved, and in addition, problems have to be solved in terms of high accuracy, cost and the like.

Patent Document 1 discloses that a sealing material is disposed around the driving element by pouring the sealing material into a region surrounded by the driving element close to the dummy element, to secure moisture resistance. However, by separately providing a sealing region, the area of the driving unit per chip is reduced, which in turn leads to the reduction of the nozzle density, and a high-density droplet head can not be realized.
Patent Document 2 discloses that the humidity around the driving part is always kept low by supplying a dry gas from the outside. However, it is necessary to provide dry air and a mechanism for supplying the same outside, which causes cost increase.
In Patent Document 3, another ultraviolet curing adhesive is applied to the outside of the adhesive for bonding the element and the plate, and is used for temporary fixing. However, the structure is not configured to prevent the entry of water into the area where the drive unit exists, and environmental resistance and durability can not be ensured.

  An object of the present invention is to provide a liquid discharge head capable of preventing moisture from infiltrating from an adhesive at a joint, and having high environmental resistance and durability.

  In order to solve the above problems, the present invention is directed to an actuator and an actuator substrate on the opposite side of the actuator to which a liquid chamber having a long side and a short side is formed in the surface direction of the substrate. A liquid discharge head in which a support substrate having a recess serving as a drive region of the actuator formed on a surface thereof is bonded with an adhesive, and the non-formation portion of the recess in the support substrate is bonded to the actuator substrate The bonding partition is arranged in the width direction of the liquid chamber, and the bonding is for bonding the bonding partition on the width direction end and the actuator substrate outside the width direction end. A moisture resistant film is formed to cover a portion where the agent is exposed.

  According to the present invention, it is possible to prevent moisture from intruding from the adhesive at the bonding portion, and it is possible to provide a liquid discharge head having high environmental resistance and durability.

FIG. 6 is a cross-sectional view in the short direction of the liquid chamber in an example of the liquid discharge head according to the present invention. FIG. 6 is a cross-sectional view in the longitudinal direction of a liquid chamber in an example of the liquid discharge head according to the present invention. FIG. 2 is a schematic plan view of an example of the liquid discharge head according to the present invention. It is a figure which shows an example of the verification result of durability. FIG. 7 is a cross-sectional view in the short direction of the liquid chamber in another example of the liquid discharge head according to the present invention. It is sectional drawing of the liquid chamber longitudinal direction in the other example of the liquid discharge head of this invention. FIG. 7 is a cross-sectional view in the short direction of the liquid chamber in another example of the liquid discharge head according to the present invention. FIG. 7 is a cross-sectional view in the short direction of the liquid chamber in another example of the liquid discharge head according to the present invention. It is sectional drawing of the liquid chamber longitudinal direction in the other example of the liquid discharge head of this invention. It is sectional drawing of the liquid chamber longitudinal direction in the other example of the liquid discharge head of this invention. FIG. 7 is a cross-sectional view in the short direction of the liquid chamber in another example of the liquid discharge head according to the present invention. It is a schematic diagram which shows an example of the apparatus which discharges the liquid which concerns on this invention. It is a schematic diagram which shows the other example of the apparatus which discharges the liquid which concerns on this invention. It is a schematic diagram which shows an example of the liquid discharge unit which concerns on this invention. It is a schematic diagram which shows the other example of the liquid discharge unit which concerns on this invention. It is a perspective view in the other example of the apparatus which discharges the liquid of this invention. It is a side view in the other example of the apparatus which discharges the liquid of this invention.

  Hereinafter, a liquid discharge head, a liquid discharge unit, and an apparatus for discharging a liquid according to the present invention will be described with reference to the drawings. In addition, this invention is not limited to embodiment shown below, It can change in the range which those skilled in the art could concidentize, such as other embodiment, addition, correction, deletion, and any aspect Even within the scope of the present invention, as long as the functions and effects of the present invention can be achieved.

  According to the present invention, there is provided an actuator, an actuator substrate on which a liquid chamber having a long side and a short side in the surface direction of the substrate is formed on the side opposite to the actuator, and a drive region of the actuator on the surface facing the actuator substrate. And a supporting substrate having a concave portion formed thereon, wherein the non-forming portion of the concave portion in the supporting substrate is a bonding partition which is bonded to the actuator substrate, and the bonding is performed. The partition walls are arranged in the width direction of the liquid chamber, and the outer side of the width direction end portion is covered so as to cover the exposed portion for bonding the bonding partition wall at the width direction end portion and the actuator substrate. And a moisture-resistant film is formed thereon.

  In the following description, the liquid chamber is described as having a long side and a short side with respect to the surface direction of the substrate, but in the present invention, for example, a liquid chamber having a square shape can not be distinguished. include. In this case, the arrangement direction of the joint partition wall is short, and the direction orthogonal to the short is long. In the following description, the actuator is also described as having a longitudinal side and a short side, but the actuator also includes an actuator which can not distinguish between the longitudinal side and the short side, such as a square, for example.

First Embodiment
One embodiment of a liquid discharge head of the present invention will be described. 1 to 3 show a liquid discharge head of the present embodiment. FIG. 1 is a cross-sectional view in the liquid chamber short side direction (arrangement direction of bonding partition walls), and is for explaining a bonding position between the bonding partition walls at the end portion in the short side direction and the actuator substrate. FIG. 2 is a cross-sectional view in the longitudinal direction of the liquid chamber, and FIG. 3 is a schematic plan view. In FIG. 3, the AA cross section corresponds to the cross sectional view of FIG. 1, and the BB cross section corresponds to the cross section of FIG. 2.

  Although a plurality of actuators 60 are illustrated in FIG. 3 and the liquid chamber 15 is omitted, the liquid chamber 15 is formed at a position corresponding to the actuator 60. The actuator 60 has a long side and a short side in the surface direction of the substrate, and the longitudinal direction and the short side direction of the actuator 60 are the same as the longitudinal direction and the short side direction of the liquid chamber 15, respectively. Further, the number of actuators 60 and liquid chambers 15 is not limited to this.

  The liquid discharge head 1 of the present embodiment has an actuator 60 and an actuator on the opposite side of the actuator 60 to which a liquid chamber 15 (also referred to as a pressurized liquid chamber) having a long side and a short side in the surface direction of the substrate. The substrate 100 and the support substrate 200 in which the recess 67 serving as the drive region of the actuator 60 is formed on the surface facing the actuator substrate 100 are bonded by the adhesive 49.

  In the actuator substrate 100, a piezoelectric body 12 for generating liquid discharge energy and a diaphragm 13 are formed, and a pressurized liquid chamber partition 14 and a liquid chamber 15 are formed. The liquid chambers 15 have longitudinal and short sides in the surface direction of the substrate, and a plurality of the liquid chambers 15 are provided in the lateral direction, and each liquid chamber 15 is partitioned by a pressurizing liquid chamber partition 14.

  The actuator 60 has a piezoelectric body 12, an individual electrode 11 and the like. The piezoelectric body 12 is sandwiched between the common electrode 10 and the individual electrode 11, and a voltage is applied by the wiring layer 42. A passivation film 50 for protecting the wiring layer 42 and an interlayer insulating film 45 for adjusting the connection between the wiring layer 42 and the common electrode 10 are formed on the actuator substrate 100.

  The non-formed portion of the concave portion 67 in the support substrate 200 is a bonding partition wall 201 to be bonded to the actuator substrate 100, and the bonding partition wall 201 is arranged in the short direction of the liquid chamber 15.

The actuator substrate 100 has a nozzle substrate 300 having a nozzle hole 16 bonded thereto, and the nozzle substrate 300 forms a part of the liquid chamber 15. Further, the droplet supply port 66, the common droplet flow path 19, and the common liquid chamber 18 are formed in the support substrate 200 and the actuator substrate 100, and the common liquid chamber 18 is in communication with the liquid chamber 15.
The liquid discharge head 1 is formed by bonding the actuator substrate 100, the support substrate 200, and the nozzle substrate 300.

  In the liquid discharge head 1 formed in this manner, a nozzle that discharges the recording liquid based on the image data from the control unit in a state where the liquid, for example, the recording liquid (ink) is filled in each liquid chamber 15 A voltage is applied to the individual electrode 11 corresponding to the hole 16.

  In this case, for example, a pulse voltage of 20 V is applied by the oscillation circuit through the lead-out wiring and the connection hole formed in the interlayer insulating film 45. When the voltage pulse is applied, the piezoelectric body 12 itself shrinks in a direction parallel to the diaphragm 13 by the electrostrictive effect, and the diaphragm 13 bends in the direction of the liquid chamber 15. As a result, the pressure in the liquid chamber 15 rapidly rises, and the recording liquid is discharged from the nozzle hole 16 communicating with the liquid chamber 15.

Next, since the contracted piezoelectric body 12 returns to its original state after application of the pulse voltage, the bent diaphragm 13 returns to its original position. For this reason, the inside of the liquid chamber 15 has a negative pressure compared to the inside of the common liquid chamber 18, and the ink supplied from the outside through the liquid droplet supply port 66 is fluid resistance from the common liquid droplet flow path 19 and the common liquid chamber 18. The liquid is supplied to the liquid chamber 15 through the unit 17.
By repeating these steps, droplets can be discharged continuously, and an image is formed on a recording medium disposed opposite to the liquid discharge head.

  Here, an inorganic material such as Si is mainly used for the supporting substrate and the actuator substrate, and the film thickness is also thick, so that they have sufficient moisture resistance to humidity. On the other hand, although an adhesive such as an epoxy resin is generally used as an adhesive for bonding the support substrate and the actuator substrate, it is difficult to use a material having sufficient moisture resistance for securing bonding quality. Therefore, the portion of the adhesive becomes a path of moisture, and the moisture intrudes into the drive region of the actuator through the adhesive. In particular, when used under a high humidity environment, there is a problem that the infiltration of water becomes remarkable, and it can not withstand long-term use.

  On the other hand, in the present embodiment, as illustrated in FIG. 1, the adhesive 49 that joins the bonding partition wall 201 at the end of the short direction end and the actuator substrate 100 to the outside of the short direction end. A moisture resistant film 71 is formed to cover the exposed portion. That is, the moisture resistant film 71 covers the outer peripheral portion of the adhesive at the bonding portion at the end portion in the short direction of the liquid chamber. Note that FIG. 1 shows the moisture-resistant film 71 at the location indicated by the reference numeral 71a in FIG. 3, but in the present embodiment, the moisture-resistant film 71 is formed also at the location indicated by the reference numeral 71b.

  By covering the adhesive 49 which joins the support substrate 200 and the actuator substrate 100 with a moisture resistant film, it is possible to block moisture entering the drive region of the actuator 60. As a result, it is possible to prevent a defect due to humidity in the drive unit, for example, a decrease in withstand voltage or discharge caused by a reduction reaction occurring in the piezoelectric body, peeling of other electrodes, and the like. Therefore, a highly reliable liquid discharge head having high environmental resistance and durability can be obtained.

  In the present embodiment, the moisture resistant film 71 is formed at the bonding portion at the end of the liquid chamber in the lateral direction, but as shown in FIG. 2, the moisture resistant film 71 is formed at the bonding portion in the liquid chamber longitudinal direction. Not formed. The outer side in the short direction of the liquid chamber is particularly easy to be in contact with the outside air, and moisture easily infiltrates from the adhesive as compared with the bonding in the longitudinal direction of the liquid chamber. Therefore, in the drive region of the actuator, the moisture-resistant film is formed on the outside of the latitudinal end and in the portion where the adhesive for bonding the bonding partition of the latitudinal end and the actuator substrate is exposed. Water can be prevented from entering, and high environmental resistance and durability can be obtained.

  Further, in the present embodiment, a special configuration is not provided in the drive region of the actuator in order to prevent the entry of water, so that the nozzle density can be prevented from decreasing. In addition to this, there is no need to separately provide a system or the like for introducing dry air for the purpose of improving the moisture resistance, and it is possible to prevent an increase in cost and to prevent the apparatus from becoming large. it can.

Also, in the related art, the barrier layer 70 is formed on the actuator in order to prevent deterioration of the actuator due to moisture entering the drive region, but the barrier layer 70 formed directly on the actuator does not move the actuator. It will inhibit.
On the other hand, in the present embodiment, since the moisture resistance of the actuator can be secured without forming the barrier layer 70 on the actuator, the displacement when the actuator is driven can be improved.

The material of the moisture resistant film 71 can be appropriately changed as long as it is a material having moisture resistance, and examples thereof include Al ₂ O ₃ , SiN, and AlN. In addition to the above, it is not limited to the shape of the film as long as the moisture resistance is secured. For example, a gasket material or the like may be used as the moisture resistant film 71.

The thickness of the moisture resistant film 71 is not particularly limited, but is preferably 20 to 500 nm.
As a method of forming the moisture resistant film 71, it is possible to appropriately change it, but among them, it is preferable to form by the ALD (Atomic Layer Deposition) method. By using the ALD method, it is possible to impart moisture resistance also to a portion which is not exposed to the surface at the time of film formation of a film having moisture resistance, such as a joint in the ink flow path, and reliability is further improved. .

<Verification of durability>
Next, the relationship between the water vapor pressure and the time to failure in the high temperature and high humidity bias test was verified for both the liquid discharge head of the embodiment having the moisture resistant film 71 and the liquid discharge head without the moisture resistant film 71. . Table 1 shows the installation conditions of the liquid discharge head and the time until failure in the high temperature and high humidity bias test. Moreover, what plotted the result in Table 1 is shown in FIG.
In the high temperature and high humidity bias test, a liquid discharge head serving as a sample was installed under the installation conditions of Table 1, and verification was performed by performing continuous driving without forming an image.

  Test Examples 1 and 2 have the moisture-resistant film 71, and are the liquid discharge heads shown in FIGS. 1 and 2 (corresponding to the plot in (A) in the figure). In Test Examples 3 to 6, the moisture-resistant film 71 was not formed in the liquid discharge head shown in FIGS. 1 and 2 (corresponding to the plot in (B) in the drawing). When comparing the test examples 1 and 2 and the test examples 5 and 6 under the same installation conditions, it can be seen that when the moisture resistant film 71 is provided, the time to failure is significantly longer and the durability is improved. Thus, it was possible to confirm that the humidity resistance is improved by forming the moisture resistant film.

<One Embodiment of Method of Manufacturing Liquid Ejection Head>
The method of manufacturing a liquid discharge head according to the present invention is
(1) Step of forming a plurality of actuators on the actuator substrate (2) Step of forming a plurality of recesses at a position corresponding to the actuator with respect to the support substrate (3) The non-formation portion of the recesses in the support substrate is the actuator substrate Bonding the actuator substrate and the support substrate with an adhesive so as to form a bonding partition to be bonded to the substrate (4) the actuator substrate has a long side and a short side in the surface direction of the substrate opposite to the actuator, Step of forming a plurality of liquid chambers in which the partition direction is the short direction at the position corresponding to the actuator (5) The outer side of the short direction end, bonding the end partition and the actuator substrate Forming a moisture resistant film so as to cover the exposed portion of the adhesive.

  Hereinafter, an example of a method of manufacturing the liquid discharge head according to the present embodiment will be described while giving a specific example. In addition, although the figure in the middle in a manufacturing process is not shown, FIGS. 1-3 becomes reference.

  First, as the actuator substrate 100, the diaphragm 13 is formed on a silicon single crystal substrate (for example, with a plate thickness of 400 μm) with a plane orientation (110). The diaphragm 13 may be either a single layer film or a laminated film as long as the function as the diaphragm and the process consistency after it are ensured.

  The diaphragm may be, for example, a silicon oxide film, a polysilicon film, an amorphous silicon film, or a silicon nitride film by LP-CVD (Low Pressure Chemical Vapor Deposition), and these may be stacked to obtain a desired diaphragm rigidity. Form a film.

In view of process consistency, diaphragm stiffness, and stress of the entire diaphragm 13, the number of laminations is preferably about 3 to 7 layers. In order to ensure adhesion with the common electrode 10 to be formed later, the uppermost layer of the diaphragm 13 is preferably a silicon oxide film formed by the LP-CVD method. Thereafter, for example, a common electrode 10 layer made of TiO ₂ and Pt is deposited to a thickness of 20 nm and 160 nm, respectively, by an oxidation process by a sputtering method / RTA (Rapid Thermal Anneal).

Next, PZT (lead zirconate titanate), for example, is formed on the common electrode 10 in a plurality of steps by spin coating, for example, to form a film of 2 μm thick as a piezoelectric body 12. Next, individual electrodes 11 made of SRO and Pt are deposited to 40 nm and 100 nm respectively by sputtering.
Here, the film forming method of the piezoelectric body 12 is not limited to the spin coating method, and may be formed by, for example, a sputtering method, an ion plating method, an air sol method, a sol gel method, an inkjet method, or the like.
Further, the individual electrodes are not limited to SRO / Pt, and Ir, IrO ₂ , Ti or the like may be used in combination.

  Then, the piezoelectric body 12 and the individual electrode 11 are formed at a position corresponding to the liquid chamber 15 to be formed later by the litho etching method. Also, the piezoelectric body 12 is formed to correspond to the position of the bonding partition wall 201. When the barrier layer 70 is provided on the actuator 60, the formation is performed after the individual electrode 11 is formed.

Next, an interlayer insulating film 45 is formed to insulate the common electrode 10, the piezoelectric body 12, and the wiring layer 42 (lead wiring) to be formed later. The interlayer insulating film 45 is formed of, for example, a 1000 nm thick SiO ₂ film by plasma CVD. The interlayer insulating film 45 does not affect the piezoelectric body 12 or the electrode material, and may be a film other than SiO _{2 of the} plasma CVD method as long as it has an insulating property.

  Next, in the interlayer insulating film 45, connection holes for connecting the individual electrodes 11 and the wiring layer 42 are formed by the lithography method. When the common electrode 10 is also connected to the wiring layer 42, a connection hole is similarly formed.

Next, as the wiring layer 42, for example, TiN / Al is deposited to a film thickness of 30 nm / 3 μm by sputtering, respectively. In the bottom of the connection hole, Pt, which is the material of the individual electrode 11 or the common electrode 10, is alloyed by the thermal history in a later step by direct contact with Al which is the material of the wiring layer 42 at the bottom of the connection hole. Is applied as a shielding layer to prevent alloying in order to prevent film peeling and the like due to stress.
The wiring layer 42 is also formed at a position to be a bonding portion with the support substrate 200.

  Next, as the passivation film 50, a silicon nitride film is formed to a thickness of 1000 nm, for example, by plasma CVD.

  Thereafter, the lead-out wiring pad portion 41 of the wiring layer 42, the actuator 60, and the common liquid droplet flow path 19 are opened by the lithography method.

  Next, the diaphragm 13 in a portion to be the common liquid droplet flow path 19 and the common liquid chamber 18 is removed by the litho etching method.

  Next, the support substrate 200 in which the recess 67 is formed at the position corresponding to the actuator 60 and the actuator substrate 100 are bonded with the adhesive 49. The adhesive 49 is applied to the side of the support substrate 200 with a thickness of about 1 μm by a general thin film transfer device.

  Thereafter, in order to form the liquid chamber 15, the common liquid chamber 18, and the fluid resistance portion 17, the actuator substrate 100 is polished by a known technique to have a desired thickness t (for example, a thickness of 80 μm). Note that etching or the like may be performed other than the polishing method.

  Next, partition walls other than the liquid chamber 15, the common liquid chamber 18, and the fluid resistance portion 17 are coated with a resist by a lithography method. Thereafter, anisotropic wet etching is performed using, for example, an alkali solution (KOH solution or TMHA solution) to form the liquid chamber 15, the common liquid chamber 18, and the fluid resistance portion 17. In addition to the anisotropic wet etching using an alkaline solution, the liquid chamber 15, the common liquid chamber 18, and the fluid resistance portion 17 may be formed by dry etching using an ICP etcher, for example.

Next, Al ₂ O ₃ is formed as the moisture-resistant film 71 so as to cover the portion where the adhesive 49 is exposed by the ALD method. In this embodiment, as shown in FIG. 1 and FIG. 3, it is the outside of the end in the lateral direction, and the location where the adhesive for joining the bonding partition 201 at the end in the lateral direction and the actuator substrate 100 is exposed. To cover the Also, the thickness is 50 nm here.

  Next, the nozzle substrate 300 having the nozzle holes 16 opened at positions corresponding to the liquid chambers 15 is bonded to the actuator substrate 100. Thus, the liquid discharge head 1 is completed. According to this embodiment, it is possible to manufacture a liquid discharge head having discharge characteristics with high accuracy and stability with high yield.

Second Embodiment
Next, other embodiments of the present invention will be described. Descriptions of matters similar to those in the above embodiment will be omitted. The liquid discharge head of this embodiment is shown in FIG. FIG. 5 is a cross-sectional view of the liquid chamber in the latitudinal direction, as in FIG. 1, and is for describing a junction between the bonding partition wall at the end in the latitudinal direction and the actuator substrate.

  The present embodiment is different from the above-described embodiment in that the moisture-resistant film 71 is formed on the entire side surface of the short direction end. The moisture-resistant film 71 may be formed so as to cover the exposed portion of the adhesive 49, and may be only in the vicinity of the bonding portion as shown in FIG. 1, but as in the present embodiment, the entire side surface A moisture resistant film 71 may be formed on the substrate. In this case, it is possible to more reliably prevent the entry of moisture into the drive region of the actuator. Further, the ALD method is particularly suitably used for producing the moisture-resistant film 71 of the present embodiment, and the manufacturing becomes easy because the mask process and the like are unnecessary.

Third Embodiment
Next, other embodiments of the present invention will be described. Descriptions of matters similar to those in the above embodiment will be omitted. The liquid discharge head of the present embodiment is shown in FIG. 6 is a cross-sectional view in the longitudinal direction of the liquid chamber as in FIG.
In the present embodiment, the moisture-resistant film 71 is formed so as to cover the outside of the liquid chamber 15 in the longitudinal direction and to which the adhesive 49 for bonding the support substrate 200 and the actuator substrate 100 is exposed. In the plan view shown in FIG. 3, this corresponds to the portions denoted by reference numerals 71c and 71d.

  Although the junction in the longitudinal direction of the liquid chamber has less infiltration of water compared to the outside in the lateral direction of the liquid chamber, in order to ensure the moisture resistance of the drive region more reliably, the moisture resistant film 71 is formed also in the longitudinal direction Is preferred. This can more reliably prevent the entry of moisture into the drive region of the actuator.

Fourth Embodiment
Next, other embodiments of the present invention will be described. Descriptions of matters similar to those in the above embodiment will be omitted. The liquid discharge head of this embodiment is shown in FIG. FIG. 7 is a cross-sectional view of the liquid chamber in the latitudinal direction, as in FIG. 1, and is for describing a joint between the bonding partition wall at the end in the latitudinal direction and the actuator substrate.

  In the present embodiment, the moisture resistant film 71 is also formed on the inner wall of the liquid chamber 15. Thereby, even when the diaphragm having no moisture resistance is used, moisture permeation from the liquid chamber surface can be prevented. Although a cross-sectional view in the longitudinal direction is not shown here, a moisture-resistant film 71 is formed on the inner wall of the liquid chamber 15 also in the cross-section in the longitudinal direction in the present embodiment.

Fifth Embodiment
Next, other embodiments of the present invention will be described. Descriptions of matters similar to those in the above embodiment will be omitted. The liquid discharge head of this embodiment is shown in FIG. 8 and FIG. FIG. 8 is a cross-sectional view of the liquid chamber in the latitudinal direction similar to FIG. 1, and is for describing a joint between the bonding partition wall at the end in the latitudinal direction and the actuator substrate. FIG. 9 is a cross-sectional view in the longitudinal direction of the liquid chamber as in FIG.

  As described above, the liquid (recording liquid, ink, etc.) discharged by the liquid discharge head flows through the flow path (common liquid droplet flow path 19 etc.) formed in the support substrate 200 and the actuator substrate 100 to the liquid chamber 15. It is supplied and discharged from the nozzle hole 16.

  In the present embodiment, among the portions where the moisture resistant film 71 is formed, the liquid contact film 72 is formed so as to separate the moisture resistant film 71 and the liquid from the locations where the moisture resistant film 71 and the liquid are in contact. In the example shown in FIG. 8, the liquid contact film 72 is formed on the moisture resistant film 71 formed on the inner wall of the liquid chamber 15. Further, in the example shown in FIG. 9, in addition to the fact that the liquid contact film 72 is formed on the moisture-resistant film 71 formed on the inner wall of the liquid chamber 15 as in FIG. A liquid contact film 72 is formed to separate the liquid.

  According to the present embodiment, both the moisture-resistant film and the liquid-resistant film can be formed by depositing both a moisture-resistant film and a liquid-resistant film on a portion such as an ink flow path that is required to be wetted. Both can be secured. This prevents the moisture resistant film 71 from being corroded by the ink material to be used, and the durability can be further improved.

The material of the liquid contact film 72 is not particularly limited as long as it is a material having liquid resistance, and may be appropriately changed depending on the type of ink, for example, Ta ₂ O ₅ , ZnO , SiO _{2 and the} like.

The thickness of the liquid contact film 72 is not particularly limited, but is preferably 20 to 200 nm. For example, in the case of Ta ₂ O _5, a film is formed to a thickness of about 50 nm.
The method for forming the liquid contact film 72 can be appropriately changed, but among them, the formation by the ALD method is preferable.

<Modification of Fifth Embodiment>
FIG. 10 shows a modification of the fifth embodiment. FIG. 10 is a cross-sectional view in the longitudinal direction of the liquid chamber as in FIG. As illustrated, the moisture resistant film 71 may be formed on the entire side surface in the longitudinal direction, and the liquid contact film 72 may be formed on the moisture resistant film 71. In this case, moisture resistance and wet resistance can be secured over a wide range.

(Other embodiments)
Next, other embodiments of the present invention will be described. Descriptions of matters similar to those in the above embodiment will be omitted. The liquid discharge head of this embodiment is shown in FIG. In the present embodiment, the barrier layer 70 is formed on the actuator 60. The present invention also includes a configuration in which the barrier layer 70 is formed on the actuator 60. In the case where the barrier layer 70 is formed, although displacement during driving is likely to be restrained, deterioration of the actuator 60 due to humidity can be further prevented, and durability can be further improved. As illustrated, the barrier layer 70 of the present embodiment is also formed under the interlayer insulating film 45.

(Liquid discharge unit, device for discharging liquid)
Next, an example of the apparatus for discharging a liquid according to the present invention will be described with reference to FIGS. 12 and 13. FIG. 12 is an explanatory plan view of an essential part of the apparatus, and FIG. 13 is an explanatory side view of an essential part of the apparatus.

  This apparatus is a serial type apparatus, and the carriage 403 reciprocally moves in the main scanning direction by the main scanning movement mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, and the like. The guide member 401 is bridged by the left and right side plates 491A and 491B and holds the carriage 403 movably. Then, the carriage 403 is reciprocated in the main scanning direction via the timing belt 408 bridged between the drive pulley 406 and the driven pulley 407 by the main scanning motor 405.

  On the carriage 403, a liquid discharge unit 440 in which a liquid discharge head 404 and a head tank 441 according to the present invention are integrated is mounted. The liquid ejection head 404 of the liquid ejection unit 440 ejects, for example, liquid of each color of yellow (Y), cyan (C), magenta (M), and black (K). Further, the liquid discharge head 404 has a nozzle row consisting of a plurality of nozzles arranged in the sub-scanning direction orthogonal to the main scanning direction, and is mounted with the discharge direction downward.

  The liquid stored in the liquid cartridge 450 is supplied to the head tank 441 by the supply mechanism 494 for supplying the liquid stored in the outside of the liquid discharge head 404 to the liquid discharge head 404.

  The supply mechanism 494 includes a cartridge holder 451 as a filling unit for mounting the liquid cartridge 450, a tube 456, a liquid feeding unit 452 including a liquid feeding pump, and the like. The liquid cartridge 450 is detachably mounted to the cartridge holder 451. The liquid is fed from the liquid cartridge 450 to the head tank 441 by the liquid feeding unit 452 via the tube 456.

  The apparatus includes a transport mechanism 495 for transporting the sheet 410. The transport mechanism 495 includes a transport belt 412 which is transport means, and a sub scanning motor 416 for driving the transport belt 412.

  The conveyance belt 412 adsorbs the sheet 410 and conveys the sheet 410 at a position facing the liquid discharge head 404. The conveyance belt 412 is an endless belt and is stretched between the conveyance roller 413 and the tension roller 414. The adsorption can be performed by electrostatic adsorption or air suction.

  The conveyance belt 412 rotates in the sub-scanning direction as the conveyance roller 413 is rotationally driven by the sub-scanning motor 416 via the timing belt 417 and the timing pulley 418.

  Further, on one side of the carriage 403 in the main scanning direction, a maintenance recovery mechanism 420 for maintaining and recovering the liquid discharge head 404 is disposed on the side of the transport belt 412.

  The maintenance and recovery mechanism 420 includes, for example, a cap member 421 for capping the nozzle surface (surface on which the nozzle is formed) of the liquid discharge head 404, a wiper member 422 for wiping the nozzle surface, and the like.

  The main scanning movement mechanism 493, the supply mechanism 494, the maintenance recovery mechanism 420, and the transport mechanism 495 are attached to a housing including the side plates 491A and 491B and the back plate 491C.

  In this apparatus configured as described above, the sheet 410 is fed and adsorbed onto the conveyance belt 412, and the sheet 410 is conveyed in the sub-scanning direction by the circumferential movement of the conveyance belt 412.

  Therefore, the liquid ejection head 404 is driven according to the image signal while moving the carriage 403 in the main scanning direction, thereby ejecting the liquid onto the stopped sheet 410 to form an image.

  As described above, in this apparatus, since the liquid discharge head according to the present invention is provided, a high quality image can be stably formed.

  Next, another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 14 is an explanatory plan view of the main part of the unit.

  Among the members constituting the device for discharging the liquid, the liquid discharge unit includes a housing portion constituted by the side plates 491A and 491B and the back plate 491C, the main scanning movement mechanism 493, the carriage 403, and the liquid It comprises the discharge head 404.

  It is also possible to configure a liquid discharge unit in which at least one of the aforementioned maintenance and recovery mechanism 420 and the supply mechanism 494 is further attached to, for example, the side plate 491B of this liquid discharge unit.

  Next, still another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 15 is a front view of the unit.

  The liquid discharge unit includes a liquid discharge head 404 to which a flow path component 444 is attached, and a tube 456 connected to the flow path component 444.

  The channel component 444 is disposed inside the cover 442. Instead of the flow path component 444, a head tank 441 can be included. Further, a connector 443 electrically connected to the liquid discharge head 404 is provided on the upper portion of the flow path component 444.

  In the present application, the “device for discharging a liquid” is a device including a liquid discharge head or a liquid discharge unit, and driving the liquid discharge head to discharge the liquid. The device for discharging the liquid includes not only a device capable of discharging the liquid to those to which the liquid can adhere, but also a device for discharging the liquid into the air or into the liquid.

  This "device for discharging liquid" can also include means related to feeding, transporting, and discharging of those to which the liquid can be attached, as well as a pre-processing device, a post-processing device, and the like.

  For example, as a “device for discharging a liquid”, an image forming device which is a device for discharging an ink to form an image on a sheet, and forming a powder in layers to form a three-dimensional object (three-dimensional object) There is a three-dimensional modeling apparatus (three-dimensional modeling apparatus) which discharges a modeling liquid to the powder layer.

  Further, the “device for discharging liquid” is not limited to a device in which a significant image such as characters and figures is visualized by the discharged liquid. For example, those which form patterns having no meaning per se and those which form three-dimensional images are included.

  The above-mentioned "thing to which liquid can be attached" means one to which liquid can be attached at least temporarily, which adheres and adheres, and adheres and penetrates. Specific examples include recording media such as paper, recording paper, recording paper, film, cloth, electronic substrates, electronic components such as piezoelectric elements, and media such as powder layers (powder layers), organ models, and inspection cells. Yes, and unless otherwise specified, all things to which the liquid adheres are included.

  The material of the above "the one to which the liquid can adhere" is paper, yarn, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, building materials such as wallpaper and floor materials, textiles such as textiles for clothing, etc. Even if it adheres, it is good.

  The "liquid" also includes inks, processing liquids, DNA samples, resists, pattern materials, binders, modeling liquids, or solutions and dispersions containing amino acids, proteins, calcium and the like.

  Further, as the “device for discharging the liquid”, there is a device in which the liquid discharge head and the device to which the liquid can be attached relatively move, but it is not limited to this. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.

  In addition, as “a device for discharging a liquid”, a treatment liquid application device for discharging a treatment liquid onto a sheet of paper to apply the treatment liquid to the surface of the sheet for the purpose of reforming the surface of the sheet, etc. There is an injection granulator etc. which granulates the fine particles of the raw material by injecting the composition liquid which is dispersed in the solution through the nozzle.

  The “liquid discharge unit” is a liquid discharge head in which functional parts and mechanisms are integrated, and is a collection of parts related to the discharge of liquid. For example, the “liquid discharge unit” includes a combination of at least one of the configuration of a head tank, a carriage, a supply mechanism, a maintenance recovery mechanism, and a main scanning movement mechanism with a liquid discharge head.

  Here, integration means, for example, one in which the liquid discharge head and the functional component or mechanism are fixed to each other by fastening, bonding, engagement or the like, or one in which one is held movably with respect to the other. Including. In addition, the liquid discharge head, the functional components, and the mechanism may be configured to be removable from each other.

  For example, as a liquid discharge unit, there is a liquid discharge unit in which a liquid discharge head and a head tank are integrated as in the liquid discharge unit 440 shown in FIG. In addition, there is one in which the liquid discharge head and the head tank are integrated by being connected to each other by a tube or the like. Here, it is possible to add a unit including a filter between the head tank of these liquid discharge units and the liquid discharge head.

  Further, as a liquid discharge unit, there is one in which a liquid discharge head and a carriage are integrated.

  Further, as a liquid discharge unit, there is one in which the liquid discharge head is movably held by a guide member constituting a part of the scanning movement mechanism, and the liquid discharge head and the scanning movement mechanism are integrated. Further, as shown in FIG. 14, there is a liquid discharge unit in which a liquid discharge head, a carriage, and a main scanning movement mechanism are integrated.

  Further, as a liquid discharge unit, there is one in which a cap member which is a part of a maintenance recovery mechanism is fixed to a carriage attached with a liquid discharge head, and the liquid discharge head, the carriage and the maintenance recovery mechanism are integrated. .

  In addition, as a liquid discharge unit, as shown in FIG. 15, there is a type in which a tube is connected to a liquid discharge head to which a head tank or a flow path part is attached, and the liquid discharge head and supply mechanism are integrated. .

  The main scanning movement mechanism also includes a single guide member. The supply mechanism also includes a single tube and a single loading unit.

  Moreover, the "liquid discharge head" is not limited to the pressure generating means used. For example, in addition to the piezoelectric actuator (which may use a laminated piezoelectric element) as described in the above embodiment, the thermal actuator using an electrothermal transducer such as a heating resistor, a diaphragm and a counter electrode An electrostatic actuator or the like may be used.

  Further, in the terms of the present application, image formation, recording, printing, printing, printing, modeling, and the like are all synonymous.

<One embodiment of device for discharging liquid>
An example of an apparatus for ejecting a liquid according to the present embodiment, which is an ink jet recording apparatus, will be described with reference to FIGS. FIG. 16 is a perspective view of the ink jet recording apparatus of the present embodiment, and FIG. 17 is a side view of the same apparatus.

  The ink jet recording apparatus 90 includes a carriage 98 movable in the scanning direction inside the apparatus main body, a liquid discharge head 1 mounted on the carriage 98, an ink cartridge 99 for supplying ink to the liquid discharge head 1, and the like. A sheet feeding cassette (or a sheet feeding tray) 93 capable of loading a large number of sheets 92 from the front side is detachably mounted at the lower part of the apparatus main body, accommodating the unit 91 and the like.

  In addition, a manual feed tray 94 opened to manually feed the sheet 92 is provided, and the sheet 92 fed from the sheet feeding cassette 93 or the manual feed tray 94 is taken in, and a required image is recorded by the printing mechanism unit 91. Thereafter, the sheet is discharged to the mounted discharge tray 95 on the rear side.

  The printing mechanism portion 91 holds the main guide rod 96, the secondary guide rod 97 and the carriage 98 which are guide members horizontally extended on left and right side plates (not shown) so as to be slidable in the main scanning direction. The liquid ejection heads 1 for ejecting ink droplets of each color of (Y), cyan (C), magenta (M), and black (Bk) are arranged in a direction intersecting the main scanning direction with a plurality of ink ejection openings (nozzles). The ink droplet ejection direction is directed downward. Further, the ink cartridges 99 for supplying the ink of each color to the liquid ejection head 1 are exchangeably mounted on the carriage 98.

  The ink cartridge 99 has an atmosphere port communicating with the atmosphere at the upper side, a supply port for supplying the ink to the liquid discharge head 1 at the lower side, and has a porous body filled with the ink in the inside. The ink supplied to the liquid discharge head 1 is maintained at a slight negative pressure by the capillary force of the matrix. Further, although the liquid ejection head 1 of each color is used as the liquid ejection head 1, one liquid ejection head having a nozzle for ejecting ink droplets of each color may be used.

Here, the carriage 98 is slidably fitted on the main guide rod 96 on the rear side (paper conveyance downstream side) and slidably mounted on the secondary guide rod 97 on the front side (paper conveyance upstream side). There is.
Then, in order to move and scan the carriage 98 in the main scanning direction, the timing belt 104 is stretched between the drive pulley 102 and the driven pulley 103 driven to rotate by the main scanning motor 101, and the timing belt 104 is moved to the carriage 98. The carriage 98 is reciprocally driven by the forward and reverse rotation of the main scanning motor 101.

  On the other hand, in order to convey the sheet 92 set in the sheet feeding cassette 93 downward to the liquid discharge head 1, the sheet feeding roller 105 and friction pad 106 for separately feeding the sheet 92 from the sheet feeding cassette 93; The guide member 107 for guiding, the conveyance roller 108 for conveying the fed sheet 92 by inverting it, and the feed rollers 109 to be pressed against the circumferential surface of the conveyance roller 108 and the delivery angle of the sheet 92 from the conveyance roller 108 are specified. And a tip roller 110. The transport roller 108 is rotationally driven by the sub scanning motor via a gear train.

  A print receiving member 111, which is a sheet guide member, is provided to guide the sheet 92 delivered from the transport roller 108 below the liquid discharge head 1 in accordance with the movement range of the carriage 98 in the main scanning direction. . On the downstream side of the printing receiving member 111 in the sheet conveying direction, there are provided a rotationally driven conveying roller 112 and a spur 113 for delivering the sheet 92 in the sheet discharging direction. Further, a discharge roller 114 for discharging the sheet 92 to the discharge tray 95, a spur 115, and guide members 116 and 117 for forming a discharge path are provided.

  At the time of recording by the ink jet recording apparatus 90, the liquid discharge head 1 is driven according to the image signal while moving the carriage 98 to discharge the ink onto the stopped paper 92 to record one line, and then, After transporting the sheet 92 by a predetermined amount, the next line is recorded. By receiving a recording end signal or a signal that the rear end of the sheet 92 has reached the recording area, the recording operation is ended and the sheet 92 is discharged.

  Further, a recovery device 127 for recovering a discharge failure of the liquid discharge head 1 is disposed at a position out of the recording area on the right end side in the moving direction of the carriage 98. The recovery device 127 has capping means, suction means and cleaning means. The carriage 98 is moved to the recovery device 127 during printing standby, and the capping means cap the liquid discharge head 1 to keep the discharge port in a wet state, thereby preventing discharge failure due to ink drying. Further, by discharging the ink not related to the recording in the middle of the recording or the like, the ink viscosity of all the discharge ports is made constant, and the stable discharge state is maintained.

  When a discharge failure occurs, etc., the discharge outlet (nozzle) of the liquid discharge head 1 is sealed by the capping means, and ink and air bubbles etc are sucked from the discharge outlet by the suction means through the tube, The attached ink, dust, etc. are removed by the cleaning means, and the discharge failure is recovered. Further, the sucked ink is discharged to a waste ink reservoir provided at the lower part of the main body, and absorbed and held by the ink absorber inside the waste ink reservoir.

  As described above, since the liquid discharge head 1 manufactured according to the present invention is mounted in the ink jet recording apparatus 90, stable ink discharge characteristics can be obtained, and image quality is improved. In the above description, the case where the liquid ejection head 1 is used for the inkjet recording device 90 has been described, but the liquid ejection head 1 is applied to a device that ejects droplets other than ink, for example, liquid resist for patterning. It is also good.

DESCRIPTION OF SYMBOLS 1 liquid discharge head 10 common electrode 11 individual electrode 12 piezoelectric element 13 diaphragm 14 pressurization partition 15 liquid chamber 16 nozzle hole 17 fluid resistance part 18 common liquid chamber 19 common liquid droplet flow path 41 lead wiring pad part 42 wiring layer 45 interlayer Insulating film 49 Adhesive 50 Passivation film 60 Actuator 66 Droplet supply port 67 Concave 70 Barrier layer 71 Moisture resistant film 72 Wetted film 100 Actuator substrate 200 Supporting substrate 201 Bonding partition wall 300 Nozzle substrate 401 Guide member 403 Carriage 404 Liquid discharge head 405 Main Scan motor 406 Drive pulley 407 Driven pulley 408 Timing belt 410 Paper 412 Transport belt 413 Transport roller 414 Tension roller 416 Sub-scan motor 417 Timing belt 418 Timing pulley 420 Maintain Recovery mechanism 421 Cap member 422 Wiper member 440 Liquid discharge unit 441 Head tank 442 Cover 443 Connector 444 Flow path part 450 Liquid cartridge 451 Cartridge holder 452 Liquid transfer unit 456 Tube 491A, 491B Side plate 491C Back plate 493 Main scan movement mechanism 494 Supply mechanism 495 Transport mechanism

Unexamined-Japanese-Patent No. 2007-237474 Japanese Patent Application Laid-Open No. 2005-074966 Patent No. 5321143

Claims (10)

An actuator, and an actuator substrate on the opposite side of the actuator to which a liquid chamber having a long side and a short side with respect to the surface direction of the substrate is formed;
A liquid discharge head comprising an adhesive and a supporting substrate having a recess formed on a surface facing the actuator substrate, which is a drive region of the actuator.
The non-formation portion of the concave portion in the support substrate is a bonding partition which is bonded to the actuator substrate, and the bonding partition is arranged in the short direction of the liquid chamber,
A moisture-resistant film is formed on the outside of the lateral direction end so as to cover a portion where the adhesive for joining the bonding partition of the lateral direction end and the actuator substrate is exposed. Liquid discharge head.   The liquid discharge head according to claim 1, wherein the moisture resistant film is formed on the entire side surface of the short direction end.   The moisture resistant film is formed on the outer side in the longitudinal direction of the liquid chamber, and is formed to cover a portion where the adhesive for bonding the support substrate and the actuator substrate is exposed. The liquid discharge head according to 1 or 2.   The liquid discharge head according to any one of claims 1 to 3, wherein the moisture resistant film is formed on an inner wall of the liquid chamber. The liquid discharged by the liquid discharge head flows through a flow path formed in the support substrate and the actuator substrate, and is supplied to the liquid chamber.
The liquid contact film is formed in a portion where the moisture resistant film and the liquid are in contact with each other in the portion where the moisture resistant film is formed, so as to separate the moisture resistant film and the liquid. The liquid discharge head according to any one of the above.   A liquid discharge unit comprising the liquid discharge head according to any one of claims 1 to 5.   A head tank for storing liquid to be supplied to the liquid discharge head, a carriage for mounting the liquid discharge head, a supply mechanism for supplying liquid to the liquid discharge head, a maintenance recovery mechanism for maintaining and recovering the liquid discharge head, the liquid 7. The liquid discharge unit according to claim 6, wherein the liquid discharge head is integrated with at least one of a main scanning movement mechanism for moving the discharge head in the main scanning direction.   An apparatus for discharging a liquid comprising the liquid discharge head according to any one of claims 1 to 5 or the liquid discharge unit according to claim 6 or 7. Forming a plurality of actuators on an actuator substrate;
Forming a plurality of recesses in a position corresponding to the actuator with respect to the support substrate;
Bonding the actuator substrate and the support substrate with an adhesive so that the non-formation portion of the concave portion in the support substrate becomes a bonding partition to be bonded to the actuator substrate;
A plurality of liquid chambers having longitudinal and short sides with respect to the surface direction of the substrate on the side opposite to the actuator with respect to the actuator substrate, the direction in which the junction partition is arranged being the lateral direction correspond to the actuator Forming in position,
Forming a moisture-resistant film on the outside of the lateral direction end so as to cover a portion where the adhesive for bonding the bonding partition of the end and the actuator substrate is exposed. Method of manufacturing liquid discharge head. 10. The method of manufacturing a liquid discharge head according to claim 9, wherein the moisture resistant film is formed by an ALD method.