JP2004249668A - Droplet discharge head, ink cartridge, and ink jet recording apparatus - Google Patents

Abstract

A high-precision and highly-reliable actuator capable of discharging liquid droplets at high density, suppressing the width of excessive leakage of an adhesive bonding the substrates, and obtaining a highly reliable actuator. And a liquid droplet ejection head.
In a substrate, a diaphragm is formed on a silicon substrate by a laminated film through an individual electrode and a gap. In the substrate 2, a pressurized liquid chamber 21, a fluid resistance groove 22, and a common liquid chamber 23 are formed in a silicon substrate 20. Each of the pressurized liquid chambers 21 is provided with a communication port 25. In the substrate 3, a nickel substrate 30 having a thickness of 35 μm is used. A nozzle hole 31 is provided in the surface portion of the substrate 2 so as to communicate with the communication port 25 of each pressurized liquid chamber 21, and the ink is communicated with the common ink chamber 23. A supply port 32 is provided. The substrate 1 and the substrate 2 and the substrate 2 and the substrate 3 are respectively bonded with an adhesive. At this time, a slit 24 is provided on the joint surface between the substrates, such as on the partition wall 26 between the pressurized liquid chambers 21 of the substrate 2.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a liquid droplet ejection head, an ink cartridge using the liquid droplet ejection head, and an ink jet recording apparatus, and can be applied to, for example, a micropump, a projector, and the like used for conveying or transferring a minute flow rate of a liquid. Related to various actuators.
[0002]
[Prior art]
The ink jet head is a droplet discharge head used in an image recording apparatus such as a printer, a facsimile, a copying apparatus or an ink jet recording apparatus used as an image forming apparatus. The ink jet head includes a nozzle for discharging ink droplets, a discharge chamber (also referred to as a pressurized liquid chamber, a pressure chamber, an ink flow path, etc.) communicating with the nozzle, and a pressure for pressurizing ink in the discharge chamber. A pressure generating means for generating the pressure, and pressurizing the ink in the discharge chamber with the pressure generated by the pressure generating means to discharge the ink droplet from the nozzle.
[0003]
Such a droplet discharge head is a piezo type that discharges ink droplets by deforming and displacing a diaphragm forming the wall surface of a discharge chamber using an electromechanical transducer such as a piezoelectric element as a pressure generating means. A bubble type (thermal type) in which a bubble is generated by ink film boiling using an electrothermal conversion element such as a heating resistor disposed in the discharge to discharge ink droplets, and the walls of the discharge chamber are formed There is an electrostatic type that discharges ink droplets by deforming a vibrating plate with electrostatic force.
[0004]
In recent years, attention has been paid to bubble-type and electrostatic types that are lead-free due to environmental problems. In addition to lead-free, multiple types of electrostatic types that have little effect on the environment from the viewpoint of low power consumption have been proposed. I have.
[0005]
For example, a nozzle substrate, a liquid chamber substrate forming a common liquid chamber with a pressurized liquid chamber and a fluid resistance path communicating with the nozzle provided corresponding to the nozzle, and joined to the pressurized liquid chamber surface of the liquid chamber substrate An electrostatic inkjet head having a vibrating plate and a driving substrate provided with a gap between the vibrating plate and the individual electrode has been proposed (for example, see Patent Documents 1 and 2). One electrode functions as a diaphragm, and ink is filled on the opposite side of the diaphragm from the opposite electrode. When a voltage is applied to the pair of electrodes, an electrostatic attractive force acts between the electrodes, the electrodes (diaphragm) are deformed, and when the voltage is removed, the diaphragm returns to its original state by the elastic force, and the ink is used by using the force. Is discharged.
[0006]
Bonding methods for bonding these substrates (nozzle substrate, liquid chamber substrate, vibration plate, drive substrate) include adhesive bonding, heat welding, direct bonding using silicon, and anodic bonding. There are also methods that cannot be joined depending on the material of the substrate to be bonded. Adhesive bonding is widely used as a technique for bonding substrates relatively easily regardless of the material of the substrate.
[0007]
In an ink-jet head using a piezoelectric body or an ink-jet head using electrostatic force, a nozzle substrate that discharges ink droplets and a flow path substrate (an ink liquid chamber, a pressurized liquid chamber, and a fluid resistance part) to which the nozzle communicates are formed. ) And a substrate provided with a pressure generating mechanism for pressurizing the ink in the pressurized liquid chamber is generally joined and assembled. As a means for joining the substrates, a highly flexible adhesive is used. The method that was used is used.
[0008]
In the substrate bonding method using an adhesive, an excess adhesive may ooze out from the bonding portion, and if the oozed portion is the ink liquid chamber or the diaphragm area, the volume of the pressure chamber, the diaphragm displacement area May not be finished as designed and may cause variations. In addition, if excess adhesive leaks from the joint on the nozzle plate side, the volume of the liquid chamber may fluctuate, or at the worst, the nozzle hole may be blocked, so that the ink ejection characteristics may not be obtained as designed. is there. In particular, in the case of an ink jet head, the exudation of the adhesive causes variations in the ink ejection characteristics, and the printing accuracy and the reproducibility of the image quality are significantly reduced.
[0009]
As means for suppressing such exudation of the adhesive, for example, a method in which a concave portion for absorbing excess adhesive is provided on a nozzle substrate has been proposed (for example, see Patent Document 3). Further, for example, there is also a type in which a concave portion having a side of about 100 μm is provided on the side of a discharge chamber substrate (also referred to as a pressurized liquid chamber, a pressure chamber, an ink flow path, etc.), and excess adhesive is absorbed by the concave portion to suppress seepage. It has been proposed (for example, see Patent Documents 4 and 5). By providing concave portions on these bonding surfaces, the reliability of bonding between the substrates is improved, the exudation of the adhesive into the pressurized liquid chamber and the vibration plate is suppressed, and the variation in characteristics between the actuators is reduced, thereby achieving high quality. A simple inkjet head is obtained.
[0010]
However, it is desired that the density of the ink jet head be further increased in order to improve printing speed and image quality in the future. The exuding width of the adhesive cannot be ignored. Further, as the density of the ink jet increases, the excess adhesive seeping width on the nozzle plate side cannot be ignored, and in the worst case, the excess adhesive closes the nozzle hole, causing a problem that the nozzle does not function as a nozzle.
[0011]
In other words, when a high-density, high-quality inkjet head is manufactured using a substrate bonding method using an adhesive, bonding is increasingly performed to stabilize the actuator characteristics, improve the accuracy, or improve the manufacturing yield. It is important to control the amount of excess adhesive exuded at the time.
[0012]
Therefore, as the density of the ink jet head increases, it is desired to actively suppress the exudation width of the adhesive. However, as described in Patent Literatures 3 to 5, even if a concave portion is provided on the bonding surface, the exudation of the adhesive is about 10 to 15 μm. In the case of a 150 dpi inkjet head having a short side length of about 140 μm of the diaphragm, this seepage does not significantly affect the actuator characteristics. However, for example, in the case of an ink jet head of about 300 dpi, the short side length of the diaphragm is about 50 to 60 μm, and in the case of exuding the adhesive of 10 to 20 μm on one side (20 to 40 μm on both sides), about 1/1 of the short side length of the diaphragm. Approximately 3 to 2/3 are affected by the exudation of the adhesive, so that not only the ink characteristics as designed cannot be obtained but also the possibility that the ink does not function at the worst is easily expected.
[0013]
[Patent Document 1]
JP-A-9-39229
[Patent Document 2]
JP-A-9-39235
[Patent Document 3]
JP 2002-210965 A
[Patent Document 4]
Japanese Patent No. 3235630
[Patent Document 5]
Japanese Patent No. 3324622
[0014]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described circumstances, is capable of discharging droplets at a high density, and suppresses the width of an excessive amount of the adhesive bonding the substrates to each other, An object of the present invention is to provide a droplet discharge head, an ink cartridge integrated with the droplet discharge head, and an ink jet recording apparatus equipped with the droplet discharge head, which can obtain a highly accurate and highly reliable actuator. With that purpose.
[0015]
[Means for Solving the Problems]
The invention according to claim 1 is a flow path substrate configured to include at least an ink supply port for receiving ink supply from the outside, an ink liquid chamber, and a plurality of pressurized liquid chambers communicating with the ink discharge surface opening. A droplet discharge head comprising: a discharge-side substrate joined to an ink ejection surface of the flow path substrate; and a liquid chamber-side substrate joined to a pressurized liquid chamber surface of the flow path substrate. The joint between the narrow-wall partition part for separating each pressurized liquid chamber in the flow path substrate and the substrate on the liquid chamber side, and / or the joint between the flow path substrate and the substrate on the discharge side are any of: A step on the substrate side, and the droplet discharge head is formed by bonding the substrate on the discharge side and / or the substrate on the liquid chamber side to the flow path substrate with an adhesive. It was done.
[0016]
According to a second aspect of the present invention, there is provided a flow path substrate including at least an ink supply port for receiving an ink supply from outside, an ink liquid chamber, and a plurality of pressurized liquid chambers communicating with the ink discharge surface opening. A droplet discharge head comprising: a discharge-side substrate joined to an ink ejection surface of the flow path substrate; and a liquid chamber-side substrate joined to a pressurized liquid chamber surface of the flow path substrate. The junction between the narrow-width partition part that separates each pressurized liquid chamber in the flow channel substrate and the substrate on the liquid chamber side, and / or the junction between the flow channel substrate and the substrate on the discharge side are both There is a step on the substrate side, and the droplet discharge head is formed by bonding the substrate on the discharge side and / or the substrate on the liquid chamber side to the flow path substrate with an adhesive. Things.
[0017]
According to a third aspect of the present invention, in the first or second aspect of the present invention, an ink contact surface of a peripheral edge of the junction in the narrow partition wall portion of the flow path substrate and / or a peripheral edge of a junction of the ink ejection surface of the flow path substrate. The ink contact surface is provided with a depression.
[0018]
According to a fourth aspect of the present invention, in the first aspect of the present invention, the flow path substrate has a joint portion with the substrate on the liquid chamber side and / or a joint portion with the substrate on the discharge side. Along, a slit having a width of 10 μm or less is formed.
[0019]
According to a fifth aspect of the present invention, in the first aspect of the present invention, at least one slit is formed on the flow path substrate along a peripheral edge of the narrow partition in the narrow partition. It is characterized by having.
[0020]
According to a sixth aspect of the present invention, in the fourth or fifth aspect of the present invention, the slits formed in the flow path substrate are divided into a plurality of pieces along the narrow partition wall periphery and arranged. .
[0021]
According to a seventh aspect of the present invention, in any one of the first to sixth aspects of the present invention, the discharge side substrate and / or the liquid chamber side substrate has a width of 10 μm or less at a joint with the flow path substrate. Are formed.
[0022]
According to an eighth aspect of the present invention, in any one of the first, second, and seventh aspects of the present invention, in the liquid chamber-side substrate, a bonding portion with the narrow partition wall portion and / or the discharge-side substrate. In addition, at least one slit is formed in each of the partition portions at the junction between the communication port of the flow path substrate and the partition portion.
[0023]
According to a ninth aspect of the present invention, in any one of the first, second, seventh, and eighth aspects of the invention, the liquid chamber side substrate has a bonding portion with the narrow partition wall portion and / or the discharge side. In the substrate, a plurality of slits are arranged along a peripheral edge of the partition at a joint portion of the communication port of the flow path substrate with the partition.
[0024]
According to a tenth aspect of the present invention, there is provided an ink cartridge in which a droplet discharge head that discharges an ink droplet and an ink tank that supplies ink to the droplet discharge head are integrated with each other. A droplet discharge head according to any one of the above.
[0025]
According to an eleventh aspect of the present invention, there is provided an ink jet recording apparatus equipped with an ink jet head for discharging an ink droplet, wherein the ink jet head is the liquid drop discharging head according to any one of the first to ninth aspects. It is.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is an exploded perspective view showing a configuration example of a droplet discharge head according to an embodiment of the present invention, and FIG. 1 shows a part of the droplet discharge head in cross section.
In this configuration example, a side shooter type droplet discharge head (also referred to as an ink jet head) that discharges ink droplets from nozzle holes provided in a surface portion of a substrate will be described. The ink jet head of this configuration example has a laminated structure in which three substrates 1, 2, and 3 having a structure described in detail below are stacked.
[0027]
In the first substrate 1, a diaphragm 13 is formed on a <100> silicon substrate 10 by a laminated film through an individual electrode 11 and a gap 12. Here, an individual electrode 11 is formed on the lower surface (corresponding to the upper surface in FIG. 1) of the diaphragm 13 with a gap 12 therebetween. The voids 12 are formed by forming a sacrificial layer on the premise that the sacrificial layer is to be removed later as a laminated film in the same manner as the individual electrode material and the diaphragm material, and subsequently removing the sacrificial layer from the removal hole.
[0028]
Further, in the second substrate 2 joined to the upper surface (corresponding to the lower surface in FIG. 1) of the first substrate 1, the <110> silicon substrate 20 has a pressurized liquid chamber 21 and a groove (fluid Resistance groove) 22, and a common liquid chamber 23 for supplying ink to each pressurized liquid chamber 21. Each pressurized liquid chamber 21 is provided with a communication port 25.
[0029]
In the third substrate 3 joined to the upper surface of the second substrate (corresponding to the lower surface in FIG. 1), a nickel substrate 30 having a thickness of 35 μm is used. A nozzle hole 31 is provided so as to communicate with the communication port 25, and an ink supply port 32 is provided so as to communicate with the common ink chamber 23.
[0030]
The substrate 1 and the substrate 2 and the substrate 2 and the substrate 3 are respectively bonded using an adhesive. At this time, a slit 24 is provided on the partition wall 26 between the pressurized liquid chambers 21 of the substrate 2 in order to prevent the adhesive from seeping into the pressurized liquid chamber 21. Although not shown in FIG. 1, a slit is also provided on the communication port 25 side of the substrate 1 to which the substrate 2 is bonded in order to prevent the adhesive from seeping out to the communication port 25 of the substrate 1. I have.
[0031]
Further, although not shown in FIG. 1, a slit may be provided on the joint surface between the substrate 2 and the substrate 3 joined to the partition wall portion 26 of the substrate 1. Further, in FIG. 1, a slit is provided to absorb an extra adhesive, but a shape in which the slit is divided into a plurality may be adopted. Although not shown in FIG. 1, the portions other than the pressurized liquid chamber 21 and the spacing wall 26 of the substrate 2 that are bonded to the substrate 1 or the substrate 3 are also intended to absorb excess adhesive and prevent substrate warpage. It is preferable to form a concave portion with.
[0032]
Next, an example of the operation of the droplet discharge head configured as described above will be described.
With the inside of the pressurized liquid chamber 21 filled with ink, a pulse potential of 40 V is applied to the individual electrodes 11 by an oscillation circuit. When the surface of the individual electrode 11 is positively charged by the application of voltage, an electrostatic attraction function acts between the individual electrode 11 and the vibration plate 13, and the vibration plate 13 bends downward (corresponding to the upward direction in FIG. 1). Ink flows into the discharge chamber 21 through the resistance groove 22. Thereafter, when the pulse voltage to the individual electrode 11 is set to 0 V, the diaphragm 13 bent downward by the electrostatic force returns to its original state due to its rigidity.
[0033]
As a result, the pressure in the discharge chamber 21 sharply increases, and the ink droplets are discharged from the nozzle holes 31 toward the recording paper. By repeating this, ink can be continuously discharged.
[0034]
The force F acting between the electrodes increases in inverse proportion to the square of the distance d between the electrodes as shown in the following equation (1). Here, in the equation (1), ε is a relative dielectric constant, S is an area of a surface facing the electrode, d is a distance between the electrodes, and V is an applied voltage. Therefore, in order to drive at a low voltage, it is important to form a narrow gap between the individual electrode 11 and the diaphragm 13.
F = (εS / 2d ² ) V ² … (1)
[0035]
The droplet discharge head according to the present invention can accurately and stably produce a minute gap between the individual electrode 11 and the diaphragm 13 so that the operation of the diaphragm by electrostatic force is maximized. Can be designed.
[0036]
According to the present invention, when the substrates are joined with an adhesive, the excess adhesive absorbing portion is provided on one side (or both sides) of a joint surface of a portion that affects the droplet discharge characteristics, for example, a narrow partition wall portion between the actuators. Is provided, it is possible to suppress the exuding width of the excess adhesive. Therefore, a highly reliable actuator can be obtained in bonding using an adhesive in further miniaturization in the future. As described above, it is possible to manufacture a droplet discharge head and an actuator with high accuracy and high reliability with little performance variation at low cost.
[0037]
Hereinafter, a droplet discharge head, an ink cartridge using the same, and an ink jet recording apparatus according to the present invention will be described in detail with reference to examples such as the configuration and manufacturing method thereof.
[0038]
(Example 1)
FIG. 2 is a plan view showing a substrate provided with a pressure generating mechanism in the droplet discharge head according to the first embodiment of the present invention, and FIGS. 3 and 4 are cross-sectional views of the substrate of FIG. 3A is a cross section taken along line X1-X1 'of the substrate of FIG. 2, FIG. 3B is a cross section taken along line X2-X2' of FIG. 2, and FIG. 4A is a line Y1-Y1 'of the substrate of FIG. A cross section is shown in FIG. 4B, and a Y2-Y2 ′ cross section is also shown.
[0039]
In the substrate provided with the pressure generating mechanism provided in the droplet discharge head according to the present embodiment, the diaphragm region 41 is separated from the partition 43 by the separation groove 42, and the film (diaphragm constituting film 59) The lower layer includes an insulating film 55, an upper electrode 56, a film deflection preventing film 57, and a resin film 58. The separation groove 42 is designed so that a step does not occur between the partition 43 and the diaphragm region 41. The short side length (S) and the long side length (L) of the diaphragm region 41 are, for example, 60 μm, 800 μm, and the like, respectively. Further, the lower electrode 52a is patterned on the Si substrate 50 via the insulating film 51, so that a voltage can be applied to displace the diaphragm area 41 by electrostatic force. Further, a gap 54a for displacing the diaphragm area 41 is formed with a width of, for example, 0.2 μm.
[0040]
The sacrifice layer process is used to form the gap, and the sacrifice layer removal hole 44 is formed in the diaphragm constituting film 59 via the upper electrode opening 45. The sacrificial layer removing holes 44 are arranged at equal intervals of the long side length and at intervals equal to or shorter than the short side length of the diaphragm area 41, and the sacrificial layer removing holes 44 are formed at the same positions on the opposing sides. By arranging a plurality of sacrificial layer removing holes 44 in this manner, the sacrificial layer can be efficiently etched and the void 54a can be formed.
[0041]
In the case of an ink-jet head, an actuator for ejecting ink is a long and narrow rectangle, and generally, adjacent actuators are arranged on the long side of the actuator with a partition wall 43 interposed therebetween. Since the sacrificial layer etch is isotropic, the sacrificial layer removal efficiency is higher when the sacrificial layer removing holes 44 are arranged in the center of the sacrificial layer. However, the presence of the sacrifice layer removing hole 44 in the displacement region of the diaphragm may affect the vibration characteristics of the actuator. Therefore, it is preferable that the sacrifice layer removing hole 44 be disposed at the long side end of the diaphragm. However, the sacrifice layer removing hole 44 is preferably arranged outside the vibration region in order to avoid an influence on the displacement of the diaphragm.
[0042]
The size of the sacrifice layer removing hole 44 is preferably large from the viewpoint of sacrifice layer etching. However, when the sacrifice layer removing hole 44 is disposed on the long side of the diaphragm, the size of the sacrifice layer removing hole 44 affects the diaphragm displacement region, 43 is preferable from the viewpoint of securing the strength and sealing the hole for removing the sacrificial layer with the resin film. It is necessary to determine the size of the sacrificial layer removing hole 44 that satisfies the conflicting conditions. However, the size of the sacrifice layer removal hole 44 is determined by the sealing property of the sacrifice layer removal hole, because the removability of the sacrifice layer can be dealt with by arranging the plurality of sacrifice layer removal holes 44 in multiple rows. . In order to seal the sacrificial layer removing hole 44 with the resin film 58, the cross-sectional area of the sacrificial layer removing hole 44 as viewed from the diaphragm plane is 10 μm. ² The following is desirable.
[0043]
Next, a manufacturing process of a substrate provided with a pressure generating mechanism according to the present embodiment will be described with reference to FIGS. 5 and 6 are views for explaining a method of manufacturing the substrate of FIG.
[0044]
First, as shown in FIG. 5A, an insulating film (thermal oxide film) 51 having a thickness of 1.6 μm is formed on a Si substrate 50 having a thickness of 400 μm. Next, P-doped polysilicon is formed as a lower electrode material to a thickness of 0.4 μm. Then, the lower electrode 52a and the partition wall 52b are separated by a lithography method. Thereafter, a protective film (CVD oxide film) 53 of the lower electrode 52a and the partition wall 52b is deposited to a thickness of 0.2 μm. The protective film 53 functions as a mask material for protecting the lower electrode 52a in the sacrifice layer process and as a protective film for preventing a short circuit between the lower electrode 52a and the upper electrode 56a.
[0045]
Next, as shown in FIG. 5B, as a sacrificial layer (non-doped polysilicon), a film of 0.2 μm serving as an air gap is formed by a CVD method, and a region to be a space 54a and a partition wall portion 54b are separated by a lithoetch method. . In the case where the partition wall portion 54b is used as a wiring layer, only the partition wall portion 54b is subjected to resist patterning by a lithography method and an opening is formed, and the resistance is reduced by ion implantation and densify method. Thereafter, a protective film (CVD oxide film) 55 is deposited to a thickness of 0.1 μm. The protective film 55 functions as a mask material for protecting the upper electrode 56a in the sacrifice layer process and as a protective film for preventing a short circuit between the lower electrode 52a and the upper electrode 56a.
[0046]
Next, as shown in FIG. 5C, P-doped polysilicon is deposited to a thickness of 0.2 μm, and the upper electrode 56a and the partition 56b are separated by a lithoetch method. At the same time, the protective hole 45 is opened larger than the sacrifice layer removal hole 44 so that the upper electrode 56a of the same material as the sacrifice layer 54a is not etched when the sacrifice layer is removed. Next to the upper electrode material 56a (and the partition wall portion 56b), a nitride film 57 is deposited to a thickness of 0.2 μm as a diaphragm deflection preventing layer (diaphragm deflection preventing film) by a CVD method.
[0047]
Next, as shown in FIG. 6 (D), a sacrifice layer removing hole 44 is formed by a litho-etch method, and as shown in FIG. 6 (E), after removing the resist, the sacrifice layer 54a and the protection films 55 and 53 are removed. The sacrifice layer is completely removed by a processing method having a high etch rate selectivity, for example, an isotropic dry etching method of SF6 or a XeF2 dry etching method to form the void 54a.
[0048]
Next, as shown in FIG. 6F, a resin film 58, here, a PBO film (polybenzoxazole) is formed as a liquid contacting film by spin coating to a thickness of 1 μm. At this time, the sacrificial layer removing hole 44 is completely sealed with the PBO film 58. Thereafter, only the electrode wiring extraction pad portion is opened by a litho-etch method. Although the PBO film is taken as an example of the liquid contacting film, a film having corrosion resistance to the ink and capable of sealing the holes for removing the sacrificial layer, such as a polyimide film, may be used. Since a resin film such as the PBO film 58 can seal the sacrificial layer removing hole 44 in the atmosphere, it is formed by a chemical vapor deposition method (CVD method) or a physical vapor deposition method (PVD method) using a vacuum device. As in the case of the formed film, the gap is vacuum-sealed, and a negative pressure is not generated in the gap due to exposure to the atmosphere, so that the diaphragm does not bend and a desired displacement cannot be obtained.
Thus, the actuator section of the substrate 1 is completed.
[0049]
Next, a method of manufacturing the pressurized liquid chamber forming member in the present embodiment will be described with reference to FIGS. 7 and 8 are views for explaining a method of manufacturing the flow path substrate in the droplet discharge head according to the first embodiment of the present invention.
[0050]
First, as shown in FIG. 7A, a silicon substrate (110) 60 having a thickness of 400 μm is prepared, and a silicon oxide film 61 having a thickness of 1 μm and a silicon nitride film 62 having a thickness of 0.15 μm are formed. I do. The type of Wafer to be used may be any of double-side polished Wafer, double-side unpolished Wafer, and single-side unpolished Wafer. Further, the specific resistance does not need to be uniform. For example, in this embodiment, Wafer having a specific resistance of 0.1 to 100 Ωcm is used.
[0051]
Next, as shown in FIG. 7 (B), a resist is patterned into a shape pattern 65 of a lightening pattern 64 for flowing excess adhesive at the time of joining with the nozzle surface side communicating pipe pattern 63 on the nozzle joining surface. Thereafter, the nitride film is patterned by dry etching. In this step, the lightening pattern was formed in substantially the same shape as the pressurized liquid chamber. In this step, although not shown in the figure, a slit for absorbing excess adhesive is formed around the communication pipe 72 (see FIG. 8) with a width of, for example, 10 μm.
[0052]
Next, as shown in FIG. 7C, the oxide film is patterned into the shape of the communication tube pattern 66. Then, as shown in FIG. 7 (D), the resist liquid is formed into the shape of the pressurized liquid chamber pattern 67 on the vibration plate joining surface side and the lightening pattern 68 for allowing excess adhesive to flow in joining with the diaphragm. Patterning is performed, and only the nitride film is patterned. In this step, although not shown in the drawing, slits for absorbing the excess adhesive are formed with a width of, for example, 10 μm in the long side direction between the pressurized liquid chambers 76 (see FIG. 8).
[0053]
Next, as shown in FIG. 7E, the oxide film is patterned into the shape of the communication pipe pattern 69. Then, as shown in FIG. 8F, a mask was formed for silicon etching by ICP (Inductively Coupled Plasma) dry etcher. The thickness of the resist 70 at the time of forming the mask is 8 μm. In this embodiment, the ICP etching is performed from the nozzle plate joining surface side. Thereafter, patterning of the communicating pipe shape 71 is performed using an ICP dry etcher.
[0054]
Thereafter, as shown in FIG. 8 (G), the resist 70 is removed, silicon is anisotropically etched with an aqueous potassium hydroxide solution, and the communication tube 72 is penetrated. Then, as shown in FIG. 8H, the oxide film of the pressurized liquid chamber 73 and the lightening portions 74 and 75 at the time of joining the diaphragm is removed by wet etching. Thereafter, as shown in FIG. 8 (I), a pressurized liquid chamber 76, a pseudo liquid chamber 77 at the nozzle joining surface, and a base 78 in the excess adhesive absorbing meat are formed. When the pressurized liquid chamber is formed, a liquid supply passage 79 having a smaller cross-sectional area than the pressurized liquid chamber is also formed. In this embodiment, the anisotropic etching of silicon at the time of forming the pressurized liquid chamber is performed at a potassium hydroxide aqueous solution concentration of 30% and a processing temperature of 85 ° C.
[0055]
Finally, as shown in FIG. 8 (J), the nitride film / oxide film is removed, and then a silicon oxide film is formed to a thickness of 1 μm as an ink-resistant liquid contact film to form a pressurized liquid chamber for inkjet. A member is formed. In this embodiment, the patterning is performed so that the bonding area between the nozzle bonding surface and the diaphragm bonding surface is substantially the same, and the shape of the nozzle bonding surface is a pseudo pressurized liquid chamber.
Thus, the pressurized liquid chamber of the substrate 2 is completed.
[0056]
Next, a method of manufacturing a nozzle substrate according to the present embodiment will be described with reference to FIG. FIG. 9 is a diagram for explaining a method of manufacturing a nozzle substrate in the droplet discharge head according to the first embodiment of the present invention.
[0057]
First, as shown in FIG. 9A, a resist 81 is applied to a thickness of 90 μm on an Si substrate 80 having a thickness of 600 μm, and patterning is performed so that the resist 81 remains at a position to be a nozzle. Next, as shown in FIG. 9B, a 30 μm thick Ni82 film is formed by electroforming. At this time, the resist 81 portion does not contain Ni, and the nozzle portion 83 is formed. Then, as shown in FIG. 9C, the formed Ni 82 is peeled from the Si substrate 80, and the resist 81 of the nozzle 83 is removed.
[0058]
Next, as shown in FIG. 9D, a dry film resist (DFR) 84 is affixed to both surfaces of the Ni 82 with a laminator as a mask for the nozzle portion 83 when making the Ni 82 water repellent. At this time, the inside of the nozzle 83 is filled with the DFR 84. Then, as shown in FIG. 9E, the entire surface of the DFR on the ink discharge side is exposed and removed, leaving the DFR 84a not on the ink discharge side. As shown in FIG. 9F, a 3 μm-thick Ni-PTFE film 85 is formed by eutectoid plating on the surface from which the DFR has been removed.
[0059]
Next, as shown in FIG. 9 (G), the DFR 84a is peeled off, and heat treatment is performed at 280 ° C. for 30 seconds to diffuse PTFE as a water-repellent material onto the inner surface of the nozzle 83, thereby obtaining water repellency. Finally, as shown in FIG. 9H, a 1 μm-thick polyimide film 86 is formed on the flow channel substrate bonding surface by a thin film transfer method in order to improve the adhesiveness. Thereafter, the polyimide film 86 is cured by heat treatment at 250 ° C. Then, the nozzle substrate is cut into chips.
Thus, the substrate (nozzle substrate) 3 is completed.
[0060]
Next, the bonding between the substrate 1 and the substrate 2 and the bonding between the substrate 1 and the substrate 3 will be described with reference to FIG. FIG. 10 is a cross-sectional view for explaining the bonding state between the substrates in the droplet discharge head according to the first embodiment of the present invention. FIG. 10A shows the bonding state between the substrates according to the prior art. FIG. 10B shows a bonding state between substrates according to the present invention including the present embodiment. FIG. 11 is a plan view of the bonding state between the substrates in the droplet discharge head according to the first embodiment of the present invention viewed from the bonding surface, and is a plan view of FIG.
[0061]
An adhesive is used for joining the substrate 1 and the substrate 2 and joining the substrate 1 and the substrate 3. An adhesive having a thickness of about 1 μm is applied to the substrate 2 by a thin film transfer method, and the substrate 1 is aligned with the substrate 2 (or the substrate 2 is aligned with the substrate 3) and adhered.
[0062]
Note that the bonding between the substrates will be described in comparison with the bonding between the substrates 101a and 101b according to the related art with reference to a cross-sectional view of the bonding surface between the substrates 2 and 3 (FIG. 10). FIG. 10A shows a cross section of a substrate 2 formed by a conventional method, in which a slit is not formed in a partition wall, when the substrate 2 is bonded to the substrate 1 or the substrate 3 with an adhesive. (B) shows a bonding cross section when the substrate 2 in which the slit according to the embodiment of the present invention is formed is bonded to the substrate 1 or the substrate 3 with an adhesive. Note that FIG. 10 illustrates the substrate 1 as the substrate 101b and the substrate 2 as the substrate 102b.
[0063]
According to the prior art, as shown in FIG. 10A, when the substrate 1 (101a) is joined to the substrate 2 (102a) with an adhesive, the excess adhesive is absorbed by the partition wall 103a of the pressurized liquid chamber 104a. Since there is no portion, the adhesive 107a protrudes into the pressurized liquid chamber 104a. The protruding width 105a is, for example, about 10 to 20 μm when the thickness of the adhesive applied is 1 μm, and greatly affects the driving characteristics of the actuator.
[0064]
On the other hand, according to the present invention, as shown in FIG. 10B, since the slit 106b having a width of 10 μm is formed in the partition wall 103b, the substrate 1 (101b) and the substrate 2 ( Even in the case of bonding 102b), since the excess adhesive is absorbed by the slit 106b, the width of the adhesive protruding into the pressurized liquid chamber 104b becomes 3 μm or less. In addition, by reducing the slit width, the excess adhesive can be taken into the slit 106b by capillary action, and as a result, the amount of the adhesive that overflows into the pressurized liquid chamber 104b can be suppressed.
[0065]
As described above, by providing the slit having a width of 10 μm or less in the narrow partition wall, a sufficient volume for absorbing the excess adhesive can be secured. Further, by setting the slit width to 10 μm or less, it becomes possible to actively absorb the excess adhesive into the slit by utilizing the capillary phenomenon. Accordingly, a margin for absorbing the excess adhesive can be secured with respect to the film thickness variation at the time of applying the adhesive, so that it is possible to reduce the manufacturing variation or improve the yield. Further, since the slit is formed in the narrow partition wall, a damper effect of reducing crosstalk between adjacent actuators can be expected. As described above, not only the yield in the manufacturing process but also the droplet discharge characteristics can be improved at the same time, and a high-quality droplet discharge head and actuator can be obtained.
[0066]
FIG. 11 shows a part (a pressurized liquid chamber 104b, a slit 106b, and a partition wall 103b) of a plan view of the substrate 2 to which the present embodiment is applied, as viewed from the surface where the substrate 1 is bonded. Although the slit 106b is shown as being provided in the long side direction of the pressurized liquid chamber 104b, the slit 106b may have a shape surrounding the periphery of the pressurized liquid chamber 104b.
[0067]
In FIGS. 10B and 11, one slit 106b is provided in the partition wall 103b, but a plurality of slits may be provided as long as the strength of the partition can be obtained. By doing so, a sufficient space for absorbing the surplus adhesive is secured, and the width of infiltration of the adhesive into the pressurized liquid chamber 104b is further suppressed. Further, by providing the slit 106b in the partition 103b, a damper effect of reducing crosstalk between adjacent pressurized liquid chambers 104b can be expected.
[0068]
In this manner, by providing at least one slit in the narrow partition wall, a volume for absorbing the excess adhesive can be secured. Further, by controlling the number of slits, it is possible to obtain sufficient design freedom for realizing control of the amount of adhesive exuding, control of bonding strength, and reduction of crosstalk.
[0069]
In the first embodiment, the configuration in which the slit is provided on the pressurized liquid chamber side of the substrate 2 has been mainly described. However, the same effect can be obtained by providing this slit also on the communication port side joined to the substrate 3. Can be
[0070]
Further, in the present embodiment, the slits are provided in the substrate 2, but the slits are provided on the substrate 1 side when the substrate 1 and the substrate 2 are bonded, and on the substrate 3 side when the substrate 2 and the substrate 3 are bonded. May be provided. At this time, the substrate 2 does not need to be provided with a slit. When a slit is provided in the substrate 1, the slit may be formed by a litho-etch method at the same time as the pad opening shown in FIG. In the substrate 3, a desired slit may be formed by a litho-etch method after the eutectoid plating shown in FIG.
[0071]
In the present embodiment, the slit width is set to 10 μm, but the minimum value is determined by litho-etch, and if a general semiconductor process is used, the width is preferably 0.5 μm or more.
By combining the substrates 1, 2, and 3 with an adhesive as described above, the main part of the droplet discharge head in this embodiment is completed.
[0072]
(Example 2)
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 12 is a cross-sectional view for explaining the bonding state between the substrates in the droplet discharge head according to the second embodiment of the present invention. FIG. 13 is a sectional view illustrating the droplet according to the second embodiment of the present invention. FIG. 13 is a plan view of the bonding state between the substrates in the ejection head as viewed from the bonding surface, and is a plan view of FIG. 12.
[0073]
The droplet discharge head according to this embodiment is characterized in that the slit of the substrate 2 is divided into a plurality of slits. Therefore, the manufacturing steps of the substrate 1 and the substrate 3 are the same as those described in the first embodiment with reference to FIGS. 5 to 8, and a description thereof will be omitted. The manufacturing process of the substrate 2 is the same as that shown in the first embodiment, but the slit formed in FIGS. 7B and 7D is divided into a plurality.
[0074]
FIG. 12 shows a bonding cross section (cross section of a partition wall) when a substrate 2 having a slit formed according to another embodiment of the present invention is bonded to a substrate 1 or a substrate 3 with an adhesive. FIG. 13 is a plan view showing the arrangement of a plurality of slits arranged in the partition wall 113 between the pressurized liquid chambers 114.
[0075]
As shown in FIG. 13, since the slit 116 anisotropically etches the <110> Si substrate, the <111> plane has a tapered shape. Therefore, the depth can be controlled by the vertical width 117 and the horizontal width 118 of the slit. For example, when the vertical width is 10 μm and the short side width is 27 μm, a slit having a depth of 10 μm is formed. In FIG. 12, the slit 116 is formed on the joint surface between the substrate 2 (110b) and the substrate 1 (110a). However, the slit is also divided on the joint surface with the substrate 3.
[0076]
By dividing the slit formation of the substrate 2 into a plurality of pieces in this manner, the slit depth can be controlled, and the absorption space for the surplus adhesive can be arbitrarily set, so that the adhesive thickness can be flexibly handled. Further, since the number and depth of the slits can be easily set, it is possible to realize the optimization of the joining strength that is inconsistent with the crosstalk between the pressurized liquid chambers.
[0077]
In other words, by arranging the slits of the narrow partition wall separately, the slit depth and capacity can be freely designed, so that it is possible to control excess adhesive absorption capacity, bonding strength, and crosstalk reduction in consideration of manufacturing process variations. It becomes. Therefore, a highly reliable and highly accurate droplet discharge head and actuator can be obtained.
[0078]
In the second embodiment, the configuration in which the slit is provided on the pressurized liquid chamber side of the substrate 2 has been mainly described. However, the same effect can be obtained by providing the slit also on the communication port side which is joined to the substrate 3. Can be
[0079]
In this embodiment, the slits are provided in the substrate 2. However, the slits may be provided on the substrate 1 side when the substrates 1 and 2 are bonded, and on the substrate 3 side when the substrates 2 and 3 are bonded. good. At this time, the substrate 2 does not need to be provided with a slit.
[0080]
(Example 3)
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 14 is a cross-sectional view for explaining a bonding state between the substrates in the droplet discharge head according to the third embodiment of the present invention, and FIG. 15 is a droplet according to the third embodiment of the present invention. FIG. 15 is a plan view of the bonding state between the substrates in the ejection head as viewed from the bonding surface, and is a plan view of FIG. 14.
[0081]
The droplet discharge head according to the present embodiment is characterized in that a depression is formed around the pressurized liquid chamber of the substrate 2 and the communication pipe. Therefore, the manufacturing steps of the substrate 1 and the substrate 3 are the same as those described in the first embodiment with reference to FIGS. 5 to 8, and a description thereof will be omitted. Also, the manufacturing process of the substrate 2 is the same as that shown in the second embodiment, but before the processes shown in FIGS. 7 and 8, the recesses (hollows) 127 are formed on both surfaces of the substrate 2 by a litho-etch method. It is necessary to keep.
[0082]
FIG. 14 shows a bonding cross section (cross section of a partition wall) when the substrate 2 having the slits and depressions according to another embodiment of the present invention is bonded to the substrate 1 or the substrate 3 with an adhesive. FIG. 15 is a plan view showing the arrangement of the depressions 127 arranged in the partition wall 123 between the pressurized liquid chambers 124.
[0083]
By providing the depression 127 on the bonding surface of the substrate 1 or the substrate 2, the excess adhesive that cannot be absorbed by the partition wall portion 123 and protrudes can be absorbed by the depression 127. In particular, when the substrate 2 and the substrate 1 are joined, there is almost no influence on the diaphragm which affects the ejection characteristics, and the characteristics as designed can be obtained. Further, by providing the recess 127, the bonding area is increased, and the bonding strength between the substrates can be sufficiently ensured.
[0084]
Since the size of the recess 127 can be arbitrarily set according to the thickness of the adhesive and the viscosity of the adhesive, the degree of freedom in design is ensured. The shape of the depression may be any shape other than the shape shown in FIG. 14 as long as the excess adhesive that has leaked out can be absorbed. Here, the slit may be either continuous or divided into a plurality of slits.
[0085]
In this manner, by providing a dent at a portion of the narrow partition wall portion facing the ink chamber, the adhesive that has exuded at a portion that affects the droplet discharge characteristics can be absorbed in this dent, so Adhesive does not affect the droplet discharge characteristics at all, and good discharge characteristics can be obtained. In addition, since the surface area of the adhesive increases by the amount of the depression, an increase in the bonding strength between the substrates is expected. As described above, a highly reliable droplet discharge head and actuator having little variation can be obtained.
[0086]
In the third embodiment, the configuration in which the slits and the dents are provided on the pressurized liquid chamber side of the substrate 2 is mainly described. The effect of is obtained.
[0087]
In this embodiment, the slits and dents are provided on the substrate 2. However, the slits and dents are provided on the substrate 1 side when the substrates 1 and 2 are joined, and on the substrate 3 side when the substrates 2 and 3 are joined. May be provided. At this time, the substrate 2 does not need to be provided with a slit or a depression.
[0088]
(Example 4)
Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 16 is a plan view of the bonding state between the substrates in the droplet discharge head according to the third embodiment of the present invention, as viewed from the bonding surface.
[0089]
The droplet discharge head according to the present embodiment is characterized in that slits are formed in both substrates to be joined. Therefore, as for the manufacturing process of the substrates 1, 2, and 3, the description in each of the embodiments 1, 2, and 3 can be appropriately referred to, and the description is omitted.
[0090]
FIG. 16 shows a case where a slit 136 is provided in a partition wall portion of the pressurized liquid chamber of the substrate 2, and a slit 137 is provided on the substrate 1 at a joint surface with the substrate 2 so as to be orthogonal to the slit 136 of the substrate 1. ing.
[0091]
As shown in FIG. 16, by providing a space for absorbing the excess adhesive on both of the substrates to be bonded, not only can the excess adhesive be absorbed more than providing a slit on only one side, but also the surface area of the slit increases. However, it is expected that the adhesive strength of the bonded substrates will be improved by the surplus adhesive.
[0092]
In this way, when the substrates are joined to each other with an adhesive, a sufficient volume of the excess adhesive absorbing portion can be secured, particularly by providing the excess adhesive absorbing portion on both sides of the joining in the narrow width partition portion, so that the droplets can be secured. A droplet discharge head with improved yield and stable quality because it is possible to sufficiently suppress the infiltration of the adhesive into a portion that affects the discharge characteristics, and to secure a margin against bonding variations in the manufacturing process. Can be supplied. In addition, it will be possible to use an adhesive for further miniaturization in the future.
[0093]
Fourth Embodiment In the fourth embodiment, the configuration in which slits are provided on the substrate 2 side of the substrate 1 and the pressurized liquid chamber side of the substrate 2 is mainly described, but this slit is provided on the communication port side where the substrate 2 and the substrate 3 are joined. , The same effect can be obtained. Further, in the present embodiment, the slit 136 is provided on the substrate 1 side and the slit 137 is provided on the substrate 2 side.
[0094]
(Example 5)
Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 17 is a schematic diagram illustrating an example of a pressure generating mechanism in a droplet discharge head according to a fifth embodiment of the present invention. FIG. 17A illustrates electrostatic drive corresponding to the first to fourth embodiments. 1 shows an example of a droplet discharge head used. FIG. 17B shows an example of a droplet discharge head using a stacked PZT as a pressure generation mechanism, and FIG. 17C shows an example of a droplet discharge head using a thin film PZT as a pressure generation mechanism. FIG. 17D shows an example of a droplet discharge head using a heater as a pressure generating mechanism.
[0095]
In the first to fourth embodiments described above, the droplet discharge head 141 including the electrostatic drive electrode 142 shown in FIG. 17A is described as the pressure generating mechanism. The same effect can be obtained in droplet discharge heads (droplet discharge heads 143, 145, and 147, respectively) using a pressure generation mechanism other than electrostatic drive, such as PZT 144, thin film PZT 146, and heater 148.
[0096]
(Example 6)
Next, an example of an ink cartridge (liquid cartridge) according to the present invention will be described with reference to FIG. FIG. 18 is a diagram illustrating an example of an appearance of an ink cartridge according to a sixth embodiment of the present invention.
[0097]
The ink cartridge 150 according to the present embodiment integrates the inkjet head 152 having any one of the above-described embodiments 1 to 5 having the nozzle 151 and the like, and the ink tank 153 that supplies ink to the inkjet head 152. It is configured.
[0098]
As shown in FIG. 18, in the case of the ink tank integrated type head, the cost reduction and reliability of the head immediately lead to the cost reduction and reliability of the entire ink cartridge. As a result, the yield and reliability of the ink cartridge are improved, and the cost of the head-integrated ink cartridge can be reduced. That is, in this embodiment, the inkjet head, which is one of the droplet discharge heads according to the present invention, and the ink tank that supplies ink to the inkjet head are integrated, so that manufacturing defects are reduced and cost is reduced. be able to.
[0099]
(Example 7)
Next, an example of an ink jet recording apparatus equipped with the ink jet head according to the present invention will be described with reference to FIGS. FIG. 19 is a perspective view showing an example of an ink jet recording apparatus equipped with an ink jet head according to the seventh embodiment of the present invention, and FIG. 20 is a view showing a cross section of a mechanism of the ink jet recording apparatus of FIG. .
[0100]
The ink jet recording apparatus 160 according to the present embodiment accommodates a printing mechanism section 161 and the like inside the recording apparatus main body, and feeds a large number of sheets P from the front side under the recording apparatus main body. A cassette (or a paper feed tray) 162 can be freely inserted and removed, and a manual feed tray 163 for manually feeding paper P can be opened. The paper P fed from the printer is taken in, a required image is recorded by the printing mechanism 161, and then the paper P is discharged to a paper discharge tray 164 mounted on the rear side.
[0101]
The printing mechanism 161 includes a carriage 173 movable in the main scanning direction, a recording head 174 including an inkjet head according to the present invention mounted on the carriage 173, an ink cartridge 175 for supplying ink to the recording head 174, and the like. You. The printing mechanism 161 slides the carriage 173 in the main scanning direction (the direction perpendicular to the plane of FIG. 20) by a main guide rod 171 and a sub guide rod 172, which are guide members that are horizontally mounted on left and right side plates (not shown). keeping. The carriage 173 is provided with a plurality of ink ejection heads 174 including an inkjet head according to the present invention, which ejects ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk). The outlets (nozzles) are arranged in a direction crossing the main scanning direction, and are mounted with the ink droplet ejection direction facing downward. In addition, each ink cartridge 175 for supplying each color ink to the head 174 is exchangeably mounted on the carriage 173.
[0102]
The ink cartridge 175 has an air port communicating with the atmosphere above, a supply port for supplying ink to the inkjet head 174 below, and a porous body filled with ink inside. The ink supplied to the inkjet head 174 by the capillary force is maintained at a slight negative pressure. Although the heads 174 of the respective colors are used as the recording heads here, a single head having nozzles for ejecting ink droplets of the respective colors may be used.
[0103]
Here, the carriage 173 is slidably fitted to the main guide rod 171 on the rear side (downstream side in the paper conveyance direction), and slidably mounted on the slave guide rod 172 on the front side (upstream side in the paper conveyance direction). It is location. In order to move and scan the carriage 173 in the main scanning direction, a timing belt 176 is stretched between a driving pulley 178 and a driven pulley 179 that are driven to rotate by a main scanning motor 177, and the timing belt 176 is attached to the carriage 173. , And the carriage 173 is reciprocated by the forward and reverse rotation of the main scanning motor 177.
[0104]
On the other hand, in order to transport the sheet P set in the sheet cassette 162 to the lower side of the head 174, the inkjet recording apparatus 160 includes a sheet feed roller 181 and a friction pad 182 that separate and feed the sheet P from the sheet cassette 162. A guide member 183 for guiding the paper P, a transport roller 184 for inverting and transporting the fed paper P, a transport roller 185 pressed against the peripheral surface of the transport roller 184, and the paper P from the transport roller 184. And a tip roller 186 for defining the feeding angle of the roller. The transport roller 184 is driven to rotate by a sub-scanning motor 187 via a gear train.
[0105]
The ink jet recording apparatus 160 is further provided with a printing receiving member 188. The print receiving member 188 is a paper guide member that guides the paper P sent from the transport roller 184 below the recording head 174 in accordance with the movement range of the carriage 173 in the main scanning direction. On the downstream side of the printing receiving member 188 in the sheet transport direction, there are provided transport rollers 191 and spurs 192 that are driven to rotate in order to deliver the sheet P in the sheet ejection direction. Rollers 193, spurs 194, and guide members 195 and 196 forming a paper discharge path are provided.
[0106]
At the time of recording, by driving the recording head 174 according to the image signal while moving the carriage 173, ink is ejected onto the stopped paper P to record one line, and after the paper P is conveyed by a predetermined amount, Record the next line. Upon receiving a recording end signal or a signal indicating that the rear end of the sheet P has reached the recording area, the recording operation is terminated and the sheet P is discharged.
[0107]
Further, a recovery device 197 for recovering from the ejection failure of the head 174 is disposed at a position outside the recording area on the right end side in the moving direction of the carriage 173. The recovery device 197 has a cap unit, a suction unit, and a cleaning unit. The carriage 173 is moved to the recovery device 197 side during the standby for printing, the head 174 is capped by the capping means, and the ejection opening is kept in a wet state, thereby preventing ejection failure due to ink drying. In addition, by discharging ink that is not related to printing during printing or the like, the ink viscosity of all the discharge ports is kept constant, and stable discharge performance is maintained.
[0108]
When a discharge failure occurs, the discharge port (nozzle) of the head 174 is sealed by a capping means, bubbles are sucked out of the discharge port with ink by a suction means through a tube, and ink or dust adhered to the discharge port surface. Is removed by the cleaning means, and the ejection failure is recovered. The sucked ink is discharged to a waste ink reservoir (not shown) provided at a lower portion of the main body, and is absorbed and held by an ink absorber inside the waste ink reservoir.
[0109]
As described above, in the ink jet recording apparatus according to the present invention, since the ink jet head embodying the present invention is mounted, there is no ink drop discharge failure due to the diaphragm driving failure, and stable ink drop discharge characteristics can be obtained. And the image quality is improved. In addition, manufacturing defects are reduced, and cost reduction can be achieved. Furthermore, since a head that can be driven at a low voltage is mounted, the power consumption of the entire inkjet recording apparatus can be reduced.
[0110]
In the present embodiment, the present invention is applied to an ink jet head, but the present invention can be applied to a liquid droplet discharging head for discharging liquid droplets other than ink, for example, a liquid resist for patterning.
[0111]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the present invention, in a droplet discharge head capable of performing high-quality printing with high-density droplet discharge characteristics, an adhesive for bonding substrates is surplus by efficiently disposing a step on a substrate bonding surface. Thus, it is possible to obtain a highly accurate and highly reliable actuator by suppressing the width of bleeding into the actuator. In other words, according to the present invention, when the substrates are bonded to each other with the adhesive, the excess adhesive absorbing portion is provided on one side of the bonding surface of a portion that affects the droplet discharge characteristics, for example, the narrow partition wall portion between the actuators. By providing the adhesive, the width of the exuded excess adhesive can be suppressed. In addition, since the excess adhesive absorbing portion is provided on both surfaces to be joined, particularly in the narrow partition wall portion, a sufficient volume of the excess adhesive absorbing portion can be ensured, so that the adhesive dyeing to a portion that affects the droplet discharge characteristics can be performed. Can be suppressed sufficiently. In any of the configurations, a highly reliable actuator can be obtained in bonding using an adhesive in the increasingly finer structure in the future, and therefore, a droplet discharge head having high accuracy and high reliability with little performance variation. In addition, the actuator can be manufactured at low cost.
[0112]
Further, according to the present invention, it is possible to provide an ink cartridge in which the droplet discharge head is integrated, and an ink jet recording apparatus equipped with the droplet discharge head.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view illustrating a configuration example of a droplet discharge head according to an embodiment of the present invention.
FIG. 2 is a plan view showing a substrate provided with a pressure generating mechanism in the droplet discharge head according to the first embodiment of the present invention.
FIG. 3 is a cross-sectional view of the substrate of FIG. 2, taken along line X1-X1 ′ and X2-X2 ′.
FIG. 4 is a sectional view taken along lines Y1-Y1 'and Y2-Y2' of the substrate of FIG. 2;
FIG. 5 is a view for explaining a method of manufacturing the substrate of FIG. 2;
6 is a view following FIG. 5 for explaining the method of manufacturing the substrate in FIG. 2;
FIG. 7 is a view for explaining a method of manufacturing the flow path substrate in the droplet discharge head according to the first embodiment of the present invention.
FIG. 8 is a view, subsequent to FIG. 7, for explaining a method of manufacturing the flow path substrate in the droplet discharge head according to the first embodiment of the present invention.
FIG. 9 is a diagram for explaining a method of manufacturing the nozzle substrate in the droplet discharge head according to the first embodiment of the present invention.
FIG. 10 is a cross-sectional view for explaining a bonding state between the substrates in the droplet discharge head according to the first embodiment of the present invention.
FIG. 11 is a plan view of FIG. 10;
FIG. 12 is a cross-sectional view for explaining a bonding state between substrates in a droplet discharge head according to a second embodiment of the present invention.
FIG. 13 is a plan view of FIG.
FIG. 14 is a cross-sectional view for explaining a bonding state between substrates in a droplet discharge head according to a third embodiment of the present invention.
FIG. 15 is a plan view of FIG.
FIG. 16 is a plan view for explaining a bonding state between substrates in a droplet discharge head according to a fourth embodiment of the present invention.
FIG. 17 is a schematic diagram illustrating an example of a pressure generating mechanism in a droplet discharge head according to a fifth embodiment of the present invention.
FIG. 18 is a diagram illustrating an example of an appearance of an ink cartridge according to a sixth embodiment of the present invention.
FIG. 19 is a perspective view illustrating an example of an inkjet recording apparatus equipped with an inkjet head according to a seventh embodiment of the present invention.
20 is a diagram illustrating a cross section of a mechanism section of the inkjet recording apparatus of FIG. 19;
[Explanation of symbols]
1, 2, 3 ... substrate, 10, 20, 50, 60, 80 ... silicon substrate, 11 ... individual electrode, 12 ... gap, 13 ... diaphragm, 21 ... pressurized liquid chamber (discharge chamber), 22 ... fluid resistance Grooves, 23: common liquid chamber (common ink chamber), 24: slit, 25: communication port, 26: partition wall (spacing wall), 30: nickel substrate, 31: nozzle hole, 32: ink supply port, 41: vibration Plate area, 42 separation groove, 43 partition wall, 44 sacrificial layer removal hole, 45 upper electrode opening (protection hole), 51 insulating film, 52a lower electrode, 52b, 54b, 56b partition wall, 53, 55: protective film (insulating film), 54a: void (sacrifice layer), 56a: upper electrode, 57: nitride film (prevention film), 58: resin film (PBO film), 59: diaphragm component film, 62 ... silicon nitride film, 63 ... nozzle surface side communication pipe pattern, 64, 68 ... lightening Pattern, 65: Shape pattern, 66, 69, 71: Communication pipe pattern, 67: Pressurized liquid chamber pattern, 70: Resist, 72: Communication pipe, 73, 76: Pressurized liquid chamber, 74, 75 ... Lightening portion, 77: Simulated liquid chamber, 78: Base, 79: Liquid supply path, 81: Resist, 82: Ni, 83: Nozzle, 84: DFR, 85: Ni-PTFE film, 86: Polyimide film, 101b, 102b: substrate, 103a, 103b, 113, 123: partition, 104a, 104b: pressurized liquid chamber, 105a: protrusion width, 106b, 116, 126, 136, 137: slit, 107a: adhesive, 117 ... Vertical width, 118: horizontal width, 127: concave portion, 141, 143, 145, 147: droplet discharge head, 142: electrostatic drive electrode, 144: laminated PZT, 146: thin film PZT 148: heater, 150: ink cartridge, 151: nozzle, 152: ink jet head, 153: ink tank, 160: ink jet recording device, 161: printing mechanism, 162: paper feed cassette, 163: tray, 164: paper discharge tray , 171: Main guide rod, 172: Subordinate guide rod, 173: Carriage, 174: Ink jet head (recording head), 175: Ink cartridge, 176: Timing belt, 177: Main scanning motor, 178: Driving pulley, 179: Follower Pulley, 181: paper feed roller, 182: friction pad, 183: guide member, 184: transport roller, 185: transport roller, 186: tip roller, 187: sub-scanning motor, 188: member, 191: transport roller, 192 ... Spur, 193 ... paper ejection roller, 19 4 spurs, 195, 196 guide members, 197 recovery device.

Claims (11)

A flow path substrate including at least an ink supply port for receiving ink supply from the outside, an ink liquid chamber, and a plurality of pressurized liquid chambers communicating with the ink discharge surface opening; In a droplet discharge head including a discharge-side substrate joined to an ink ejection surface and a liquid chamber-side substrate joined to a pressurized liquid chamber surface of the flow path substrate, each of the pressures in the flow path substrate The junction between the narrow partition separating the liquid chamber and the substrate on the liquid chamber side and / or the junction between the flow path substrate and the substrate on the discharge side has a step on one of the substrate sides. The droplet discharge head is formed by bonding the substrate on the discharge side and / or the substrate on the liquid chamber side to the flow path substrate with an adhesive. A flow path substrate including at least an ink supply port for receiving ink supply from the outside, an ink liquid chamber, and a plurality of pressurized liquid chambers communicating with the ink discharge surface opening; In a droplet discharge head including a discharge-side substrate joined to an ink ejection surface and a liquid chamber-side substrate joined to a pressurized liquid chamber surface of the flow path substrate, each of the pressures in the flow path substrate The junction between the narrow partition separating the liquid chamber and the substrate on the liquid chamber side and / or the junction between the flow path substrate and the substrate on the discharge side has a step on both substrate sides. The droplet discharge head is formed by bonding the substrate on the discharge side and / or the substrate on the liquid chamber side to the flow path substrate with an adhesive. A recess is provided on the ink contact surface of the peripheral edge of the joint in the narrow partition wall portion of the flow path substrate and / or the ink contact surface of the peripheral edge of the joint on the ink ejection surface of the flow path substrate. Item 3. A droplet discharge head according to Item 1 or 2. A slit having a width of 10 μm or less is formed in the flow path substrate along a joint with the substrate on the liquid chamber side and / or a joint with the substrate on the discharge side. 4. The droplet discharge head according to any one of items 1 to 3. 5. The droplet discharge according to claim 1, wherein the flow path substrate has at least one slit formed along a peripheral edge of the narrow partition in the narrow partition. head. 6. The droplet discharge head according to claim 4, wherein the slits formed in the flow path substrate are divided into a plurality of slits along the peripheral edge of the narrow partition wall. 7. A slit having a width of 10 [mu] m or less is formed at a joint of the discharge-side substrate and / or the liquid chamber-side substrate with the flow path substrate. 2. The droplet discharge head according to 1. A slit is formed in each of the joints with the narrow-width partition walls in the substrate on the liquid chamber side and / or in the junctions with the partition walls of the communication port of the flow path substrate in the substrate on the discharge side. 8. The droplet discharge head according to claim 1, wherein at least one or more portions are formed. A slit is formed at the joint between the liquid chamber-side substrate and the narrow-width partition wall and / or at the discharge-side substrate and the junction between the communication port of the flow path substrate and the partition wall. The droplet discharge head according to any one of claims 1, 2, 7, and 8, wherein a plurality of the droplet discharge heads are arranged along. 10. An ink cartridge in which a droplet discharge head for discharging ink droplets and an ink tank for supplying ink to the droplet discharge head are integrated, wherein the droplet discharge head according to any one of claims 1 to 9. An ink cartridge, which is a droplet discharge head. An inkjet recording apparatus equipped with an inkjet head for ejecting ink droplets, wherein the inkjet head is the droplet ejection head according to any one of claims 1 to 9.

Images