JP2001341314A - Liquid jet head and its manufacturing method, ink jet recorder and microactuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic ink jet head and a microactuator for ejecting an ink drop by deforming a diaphragm forming the wall face of a liquid chamber with an electrostatic force generated between the diaphragm and an electrode thereby varying the volume/pressure in the liquid chamber in which high image quality recording can be realized at a low cost by forming a micro liquid chamber with high accuracy at a low cost. SOLUTION: A through hole 36 serving as a liquid chamber is made in a glass substrate 31 by sandblasting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a droplet discharge head, a method of manufacturing the same, an ink jet recording apparatus, and a microactuator.

[0002]

2. Description of the Related Art An ink-jet head, which is a droplet discharge head used in an ink-jet recording apparatus used as an image recording apparatus (image forming apparatus) such as a printer, a facsimile, a copying apparatus, and a plotter, has a nozzle for discharging ink droplets, A liquid chamber (also referred to as a discharge chamber, a pressure chamber, a pressurized liquid chamber, an ink flow path, etc.) with which the nozzle communicates, and pressure generating means for pressurizing the ink in the liquid chamber; By driving, the ink in the liquid chamber is pressurized to eject ink droplets from the nozzles.

Conventionally, as a pressure generating means for generating a pressure for pressurizing ink in a liquid chamber, a diaphragm forming a wall of the liquid chamber is deformed and displaced by using a piezoelectric element to change the volume in the flow path, thereby forming an ink droplet. A piezo-type device (see Japanese Patent Application Laid-Open No. 2-51734), which discharges ink droplets, or a method in which ink droplets are discharged by pressure generated by heating ink in a liquid chamber using a heating resistor to generate bubbles. A bubble type (see Japanese Patent Application Laid-Open No. 61-59911) is known.

Further, the diaphragm and the electrode forming the wall surface of the liquid chamber are arranged in parallel, and the diaphragm is deformed and displaced by an electrostatic force generated between the diaphragm and the electrode, thereby reducing the volume / pressure of the liquid chamber. There is also known an electrostatic type in which ink droplets are ejected while being changed (see JP-A-6-71882).
In addition, what is composed of a diaphragm and a piezoelectric element or an electrode is called a microactuator, and is used not only as a head but also as an actuator part of a micromotor, a micropump, and the like. I do.

[0005] As a member for forming the liquid chamber, for example, a liquid chamber or the like formed by etching using a silicon substrate, a glass substrate, a SUS substrate or the like, or a liquid chamber or the like using a dry film resist (DFR). There are various types such as those formed, a substrate having a liquid chamber or the like formed by Ni electroforming, and a liquid chamber formed by pressing a thin plate SUS.

[0006]

However, when a liquid chamber or the like is formed on a silicon substrate, a glass substrate, a SUS substrate, or the like by etching as described above, the required etching rate is generally very large. It takes a considerable amount of time to form the liquid chamber, and the cost of the head increases even if a large number of pieces are formed using a silicon wafer or the like.

Also, dry film resist (DFR)
When the liquid chamber is formed by using, the DFR swells with the ink, and the droplet discharge characteristics are likely to vary. Further, when the liquid chamber or the like is formed by Ni electroforming, the cost is high. When the liquid chamber or the like is formed by pressing using a thin plate SUS, a fine liquid chamber pattern is formed with high precision. There is a problem that it is difficult.

There is a problem that such an increase in the manufacturing cost of the head and variations in the droplet discharge characteristics directly lead to an increase in the cost of the ink jet recording apparatus and a decrease in image quality. In addition, the microactuator also has a problem that the manufacturing cost similarly increases.

The present invention has been made in view of the above points, and provides a low-cost droplet discharge head and a method of manufacturing the same, and provides an ink-jet recording apparatus capable of high-quality recording at low cost. It is an object to provide a microactuator at low cost.

[0010]

In order to solve the above-mentioned problems, a droplet discharge head according to the present invention has a configuration in which a liquid chamber is formed by a sandblast method.

Here, the blast surface of the liquid chamber is preferably smoothed. In this case, the blast surface of the liquid chamber is 2
It can be smoothed by stepwise sandblasting with abrasive grains of more than one kind of sandblast, smoothed by etching, smoothed by annealing, or smoothed by forming a surface coat layer.

Preferably, the member forming the liquid chamber is a glass substrate. In this case, it is preferable that a glass substrate forming the liquid chamber and a glass substrate provided with an electrode facing the vibration plate be joined by anodic bonding.

Furthermore, it is preferable that a water-repellent film containing polysilazane is formed on the surface of the member forming the nozzle. In this case, it is preferable that silicon oxide containing a hydroxyl group be removed from the surface of the water-repellent film containing polysilazane.

A method for manufacturing a droplet discharge head according to the present invention is a method for manufacturing a droplet discharge head according to the present invention, wherein the diameter of abrasive grains used in sandblasting is 3 to 15 μm.
The hardness is 9 to 13 in Mohs hardness. Here, in the sandblasting method, it is preferable to perform masking with a mask in which a plurality of types of flow path patterns are formed.

[0015] The ink jet recording apparatus according to the present invention comprises:
The ink jet head is configured to be the droplet discharge head according to the invention.

The microactuator according to the present invention comprises:
It has a first member provided with a vibrating plate and a second member provided with an electrode facing the vibrating plate, wherein a concave portion corresponding to the vibrating plate of the first member is formed by a sandblasting method. . Here, it is preferable that both the first member and the second member are made of a glass member and are anodically bonded.

[0017]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an explanatory cross-sectional view of an inkjet head according to a first embodiment of the present invention in the longitudinal direction of the diaphragm, FIG.
FIG. 3 is an explanatory plan view of a flow path pattern of the head.

This ink jet head has a first glass substrate 1 which is a first member which is a flow path substrate on which a diaphragm is formed by forming a flow path such as a liquid chamber, and a first glass substrate 1 is provided below the first glass substrate 1. A second glass substrate 2 as a second member, which is an electrode substrate on which an electrode is provided, and a third glass substrate 3, which is a top plate, for discharging a plurality of ink droplets (only one is shown for convenience). 4, a discharge chamber 6 which is a liquid chamber in which each nozzle 4 communicates via a nozzle communication path 5, a common liquid chamber 8 which communicates with each discharge chamber 6 through a fluid resistance portion 7 which also serves as an ink supply path, and the like. are doing.

The first glass substrate 1 has a groove for forming the nozzle 4 and the nozzle communication passage 5, a through hole (recess) for forming the liquid chamber 6, a groove for forming the fluid resistance portion 7, and a common liquid chamber. 8
A diaphragm 12 made of Mo, W, Ni or Ni—Cr or the like is formed on the bottom surface of the first glass substrate 1 to form the wall surface (bottom surface) of the liquid chamber 6. An SiO ₂ film 13 is formed on the side surface of the second glass substrate 2.

The flow paths of the first glass substrate 1 such as the nozzle 4 and the groove serving as the nozzle communication passage 5, the liquid chamber 6 and the through-hole serving as the common liquid chamber 8, and the groove serving as the fluid resistance part 7 will be described later. It is formed by the sand blast method.

A concave portion 14 for forming a gap is formed in the second glass substrate 2, and an electrode (second electrode) 15 facing the diaphragm 12 is provided on the bottom surface of the concave portion 14.
A gap 16 is formed between the diaphragm 12 and the electrode 15,
The vibrating plate 12 and the electrode 15 constitute a microactuator unit.

On the surface of the electrode 15, an insulating film 17 such as a SiO ₂ film is formed. Preferably, the thickness of the insulating film 17 is in the range of 50 to 5000 ° (0.05 to 0.5 μm). If the thickness is less than 0.05 μm, the electrode 15 will not function sufficiently as a protective film, and if it exceeds 0.5 μm, the gap 16 between the diaphragm 12 and the electrode 15 will be too large or will not be effective. The gap (here, the gap between the surfaces of the SiO ₂ films 13 and 17) is too small.

The electrode 15 can be made of a metal material such as Al, Al alloy, Cr, Ni, Ni-Cr, Pt, Au, Mo, or a high melting point metal such as Ti, TiN, or W. . Then, as shown in FIG. 2, the bottom surface of the concave portion 14 of the second glass substrate 2 is formed as an inclined surface in the short direction of the diaphragm, and the electrode 15 is formed on this bottom surface.
The electrode 15 is arranged in a non-parallel state with respect to the diaphragm 12. The gap 16 formed by the non-parallel diaphragm 12 and the electrode 15 is referred to as a non-parallel gap.

The third glass substrate 3 has an ink supply port 18 for supplying ink to the common liquid chamber 8 from outside.
The SiO ₂ film 19 is also formed on the side of the first glass substrate 1 of the third glass substrate 3.

Then, the first glass substrate 1 and the second glass substrate 2 are joined via an SiO ₂ film 13. Also,
The first glass substrate 1 and the third glass substrate 3 are also SiO ₂ films 19
Are joined through. These glass substrates 1 and 2 or the glass substrates 1 and 3 are bonded by chemical bonding of interface activation (SiO *), or after being surface-activated by chemical treatment, and then bonded by heating and pressing, or surface activity. After the chemical treatment of the chemical conversion, bonding can be performed by anodic bonding or the like.

Further, a water-repellent film 20 in which PTFE or PFA is dispersed in polysilazane is formed on the nozzle-side end surfaces (nozzle surfaces) of the first, second, and third glass substrates 1, 2, and 3. I have. The surface of the water-repellent film 20 containing polysilazane has removed silicon oxide containing hydroxyl groups.

In the ink jet head thus configured, an electrostatic force (electrostatic attraction) is generated between the diaphragm 12 and the electrode 15 by applying a driving voltage between the diaphragm 12 and the electrode 15. As a result, the diaphragm 12 is
Displaced to the side. As a result, the internal volume of the liquid chamber 6 is expanded and the internal pressure is reduced, so that the ink is filled from the common liquid chamber 8 into the pressurizing chamber 6 via the fluid resistance part 7.

Next, when the voltage application to the electrode 15 is stopped,
The electrostatic force stops working, and the diaphragm 12 is restored by its own elasticity. With this operation, the internal pressure of the liquid chamber 6 increases, and ink droplets are ejected from the nozzle 4 through the nozzle communication path 5. When a voltage is applied to the electrodes again, the diaphragm is drawn back to the electrodes by the electrostatic attraction force.

Next, a process of manufacturing the first glass substrate in the ink jet head will be described with reference to FIG. First, a resist is applied or laminated on a glass substrate 31 serving as the first glass substrate 1 as shown in FIG. 1A, exposed and developed, and the nozzle 4 and the nozzle connection are formed as shown in FIG. A mask 32 of a resist pattern for sand blast having an opening 33 corresponding to the flow path pattern of the passage 5, the liquid chamber 6, the fluid resistance part 7, and the common liquid chamber 8 is formed.

As described above, one mask 32 corresponding to each flow path pattern can be used. That is, in the sand blasting method, when the abrasive particle diameter is in the range of 3 to 15 μm, the rate of the cutting depth varies depending on the resist opening area. FIG. 5 shows the measured results of the mask opening width and the processing depth for each abrasive grain size (#
800, # 1000, and # 1500). For example, taking abrasive grain size # 1500 as an example,
When the resist width W = 40 μm, a depth D = 27 μm is obtained by cutting for a certain time, and D / W = 0.68. Similarly, when W = 100 μm, D = 64 μm and D / W =
0.64.

That is, the aspect ratios are substantially the same,
This means that the processing depth increases depending on the substantial resist opening width. Therefore, by properly designing the resist width (mask opening width) with one resist mask, a nozzle, a liquid chamber, a fluid resistance portion, and a common liquid chamber can be formed, and furthermore, not shown in this example. Can also form a buffer portion for a print drive shock wave.

Next, returning to FIG. 3 (c), after performing sand blasting using abrasive grains having a large abrasive grain size to form holes 34, as shown in FIG. A through hole 35 is formed by finishing the wall surface of the hole 34 by performing sandblasting using abrasive grains.

Here, when precision cutting by the sand blasting method is performed, the cutting can be performed using abrasive grains having an abrasive grain diameter of less than 3 μm, but the cutting rate (cutting speed) at this time is extremely small (0.5 μm). / Min), and when abrasive grains having an abrasive grain diameter of more than 15 μm are used, chipping becomes large, which is not suitable for high-speed precision cutting.

Therefore, when the liquid chamber or the like is formed by the sandblasting method, it is preferable to use abrasive grains having an abrasive grain diameter of 3 to 15 μm. In addition, the Young's modulus of a glass substrate, a silicon substrate, etc. is 500 by a sandblasting method.
In order to perform high-speed precision cutting on a substrate of kg / cm 2 or more, it is preferable to use an abrasive having a Mohs hardness of 9 to 13 as a hardness.

In this case, the particle size of the abrasive grains used and the size of chipping during cutting are substantially correlated. FIG. 6 shows the measurement results (10) of the relationship between the particle size (particle size) and the chipping size.
FIG. 4 is an explanatory diagram showing an example of the average value of
The size of chipping when using abrasive grains having an average particle size of 15 μm is about 13.4 μm, while the size of chipping when using abrasive grains having an average particle size of 3 μm is about 2.5 μm.

Therefore, in the step shown in FIG. 3, first, abrasive grains having a large particle size (for example, 15 μm) are used and 80% of the target depth is used.
, And then cutting to the target depth using abrasive grains of small particle size (for example, 3 μm), it is possible to increase the cutting speed (tact time) while reducing the size of chipping on the cutting surface. it can. For example, air pressure 2
When sand blasting is performed for about 20 minutes at 9.42 (Pa), abrasive grains (# 1500), and material SiC, a cutting pattern is formed on the substrate. Then, air pressure 29.42
(Pa), abrasive grains (# 2500), and sand blasting with the material SiC for about 5 minutes, the chipping is reduced to about 3 μm.

By performing the sandblasting while changing the abrasive grain size in this manner, chipping can be reduced to a practical level. However, chipping of about 2.5 to 3 μm has been observed. , Hair cracks (white turbidity) are observed on the surface of the cut portion. FIG. 7 is a SEM photograph of a cut portion by sandblasting, in which chipping CH and white turbidity (hair crack) HC due to sandblasting are recognized.

Therefore, as shown in FIG.
2 is removed and a smoothing process is performed to form a through hole 36 which becomes the liquid chamber 6 in which the wall surface of the through hole 35 is smoothed. As the smoothing treatment, chipping is reduced to 1 μm or less by performing chemical etching with a single acid or a mixed acid of two or more of sulfuric acid, phosphoric acid, nitric acid, and acetic acid containing minerals containing 5 to 30 wt% of hydrofluoric acid. Hair cracks due to cutting are also removed, and a glass-like surface can be secured.

Specifically, when immersion was performed for 10 minutes in an etchant containing 5% of hydrofluoric acid, 50% of H ₂ SO ₄ (sulfuric acid), 20% of NH ₄ F, and 25% of pure water, the cloudiness of the cut portion was translucent. Glass substrate. Glass substrate etch rate is about 3
With a surface etch of 00 ° / min, ie, about 3000 °, fine chippings and hair cracks are dissolved, resulting in a smooth surface.

As described above, by forming the liquid chamber by the sand blast method, the processing time can be shortened and the manufacturing cost can be reduced. Then, the blast surface of the liquid chamber is smoothed by performing stepwise sandblasting with two or more types of sandblast abrasive grains, so that the liquid chamber wall surface can be smoothed by high-speed processing, The influence on the flow of the ink can be reduced. further,
By performing etching and smoothing, the wall surface of the liquid chamber can be smoothed with higher precision. Further, by using a glass substrate as a member for forming the liquid chamber, cost reduction can be achieved.

Next, a second embodiment of the ink jet head according to the present invention will be described with reference to FIG. This embodiment is an example in which the wall surface of the liquid chamber 6 formed on the first glass substrate 1 in the above-described first embodiment is smoothed by an annealing process. Here, a manufacturing process of the first glass substrate 1 will be described.

That is, in the same manner as in the manufacturing process of the first glass substrate 1 in the first embodiment, the glass substrate 3
After forming a through-hole 35 by sandblasting in 1, annealing is performed using, for example, a carbon dioxide gas laser, and the through-hole 36 becomes a liquid chamber 6 that is smoothed by removing fine chipped scaly projections and hair cracks. Is formed.

In particular, since the glass substrate is inexpensive, it is effective in reducing the cost of the head as a constituent material of an ink jet head part. When this glass substrate is cut by the sandblasting method, the cut portion is cloudy due to irregular optical reflection due to chipping and hair crack as described above, but the resist (mask)
The portion not blasted by the glass maintains the state of the transparent glass.

Therefore, a carbon dioxide laser is applied to this glass substrate.
ー (Output is 50 ~ 300mW / cm ^Two) Laser light
When irradiated, light absorption occurs only in the cloudy areas,
Will be At this time, the glass substrate is kept at 100 to 300 ° C.
Heating prevents cracking due to heat shock
You.

Specifically, when the glass substrate 31 was heated to 300 ° C. and scan annealing was performed with the energy of 200 mW / cm ² of the carbon dioxide laser, the cloudiness of the cut portion was annealed and melted, and chipping and hair cracks were reduced. Melts into a translucent glass. By performing annealing using laser light in this manner, dust generation due to hair cracks can be suppressed by a simple dry method, nozzle clogging can be prevented, and the cost of the process can be reduced. The tact time was about 5 minutes for an 8-inch substrate.

As described above, by smoothing the wall surface of the liquid chamber by annealing treatment with a carbon dioxide gas laser or the like, a head having a liquid chamber with good surface smoothness can be formed using a glass substrate. Cost can be reduced.

Next, a third embodiment of the ink jet head according to the present invention will be described with reference to FIG. This embodiment is an example in which the surface of the liquid chamber 6 formed on the first glass substrate 1 in the above-described first embodiment is coated with a surface coat layer and is smoothed. Will be described.

That is, in the same manner as in the manufacturing process of the first glass substrate 1 in the first embodiment, the glass substrate 3
After forming through-holes 35 by sandblasting in 1, for example, chipping by sandblasting or hair cracking is spin-coated with polysilazane, and this is 150-45.
By thermally decomposing and oxidizing to 0 ° C., a surface coat layer 37 of SiO ₂ is formed, and a through-hole 36 which becomes the liquid chamber 6 whose wall surface is smoothed is formed.

Here, the thickness of the surface coat layer 37 of SiO ₂ is 500-5000 °, preferably 1000-500 °.
2000 $. The polysilazane becomes a pure amorphous SiO ₂ film by thermal decomposition oxidation, and the ink reliability (liquid contact resistance) is improved.

Specifically, a polysilazane having a viscosity of 3 cps was spin-coated at 2000 rpm to form a film of about 1500 °. This film penetrates into the voids of the hair crack and becomes a silica-coated film at a heat treatment temperature of 350 ° C. This film has a refractive index close to that of glass, the opaque blast cut portion becomes translucent, and the protective film adheres firmly as a uniform film. Thereby, the reliability and the surface smoothness are improved, and the bubble discharging property is also improved.

As described above, when the liquid chamber 6 is formed on the first glass substrate 1 by the sandblast method, the first glass substrate 1 and the second glass substrate 2 can be formed by using polysilazane as a surface coat layer such as a liquid chamber wall surface. Anodic bonding becomes easier,
Direct solid joining becomes possible at low cost.

That is, when a polysilazane film is formed on the entire surface of the first glass substrate 1, the polysilazane-treated film has good surface smoothness, and when a voltage is applied during anodic bonding,
Since there are few impurities, the resistance is high and the charges are concentrated. Thereby, the mobile ions contained in the first glass substrate 1 move together with the charge concentration to the bonding interface, and are bonded (bonded) by an ion reaction. At this time, a film thickness in a range where ion current is not reduced by high resistance, preferably 100
Set to 0 to 2000 mm. This facilitates anodic bonding.

Specifically, the first glass substrate 1 (the glass substrate 31 in the above example) is spin-coated with polysilazane to flatten the surface. At this time, the formation of the heated silicate film results in a high-resistance film with few impurities. However, 1
When a DC voltage of about 1 KV is applied to the film having a thickness of about 500 °, the movement of ions in the glass substrate is diffused to the silicate film interface, thereby performing ion bonding. Anodic bonding utilizes this phenomenon, and silicate ions in the glass have ionic conductivity when the glass substrate is heated to 250 ° C. or higher. In other words, the DC charge is concentrated on the heated glass substrate, and the mobile glass diffuses and reacts with the mobile ions.
Anodic bonding occurs.

Next, the water-repellent film 20 formed on the nozzle surface of the head according to the first embodiment will be described. As described above, when forming the flow channel by the sandblast method,
Actually, after forming a flow path pattern for a plurality of heads and joining with another substrate, the nozzle end surface is formed by dicing with a diamond saw or the like, but in this state, there is no water repellency of the ink surface, The ink drops do not fly because the nozzle surface is wet.

Therefore, the nozzle surface is formed by using polysilazane and P
It is immersed in a mixed solution of an organic fluorine compound such as TFE (polytetrafluoroethylene) or PFA (perfluoroalkyl vinyl ether copolymer), dried, and thermally baked to form a polysilazane SiO ₂ network structure of PTFE or PF.
A film (water-repellent film 20) having a configuration in which A is held is formed.
Thus, water repellency can be easily provided.

More specifically, PTFE in which 20% by weight or more of polysilazane having good adhesion to the nozzle surface is dispersed.
By immersing the nozzle surface in a mixed solution of
A water-repellent film 20 having a thickness of not less than μm was formed. The film thickness is PTF
It is affected by the particle size of E and PFA (0.5 to 1 μm).

The organofluorine polysilazane reacts with the substrate side to adhere to SiO ₂ , and the surface is exposed to a fluorine organic compound, thereby increasing the water repellency. There is a possibility that resistance to the wiping operation for removing ink from the surface is not sufficient.

Here, the water-repellent film 20 using polysilazane has the organic fluorine compound held in the network structure of SiO ₂ as described above, but partially includes a silanol group of SiOH. Has a wettability to the ink and degrades water repellency. Further, due to the strong retention of SiO _{2 having} a network structure, the ratio of the organic fluorine compound exposed to the surface is small, and sufficient water repellency may not be exhibited.

Therefore, the surface of the water-repellent film 20 is light-etched with a mixed acid solution containing 1 to 15% hydrofluoric acid (HF) to remove the SiO ₂ exposed on the surface by 100 to 2000%.
By dissolving and removing, the surface occupancy of the organic fluorine compound on the surface of the water repellent film 20 is improved, and the water repellency is increased.

Specifically, NH containing 1 to 15% of hydrofluoric acid
By light etching with a mixed acid solution with 4F,
After dissolving and removing about 2000 mm of SiO ₂ film from the surface,
By performing the heat treatment at 350 ° C., some particles of PTFE or PFA are fused, and the water repellent is exposed on the surface. By performing a smoothing treatment by wiping this surface, the water repellency is further improved.

Next, a fourth embodiment of the ink jet head according to the present invention will be described with reference to FIGS. In this embodiment, a groove forming the nozzle 4 and the nozzle communication path 5 from the second glass substrate 2 side on the first glass substrate 41, a concave portion forming the liquid chamber 6, a groove forming the fluid resistance portion 7, A concave portion or the like forming the common liquid chamber 8 is formed, and the first glass substrate 41 is formed of Mo, W, Ni, Ni-Cr, or the like on the bonding surface side of the first glass substrate 41 with the second glass substrate 2 (the bottom surface of the liquid chamber 6). A vibration plate 12 is provided, and an SiO ₂ film 13 is formed on the side surface of the second glass substrate 2 of the vibration plate 12 and bonded to the second glass substrate 2.

With this configuration, the third glass substrate serving as the top plate in the first embodiment is not required, and the configuration is simplified, and the first glass substrate 41 is used to form the liquid chamber 6 and the like. For this reason, it is not necessary to penetrate, so that the processing time is shortened and the cost can be further reduced.
In this case as well, the liquid chamber 6, the nozzle 4, the nozzle communication passage 5, and the wall surface of each groove serving as the fluid resistance part 7 are spin-coated with polysilazane as in the third embodiment described above, and this is applied to 150 to By thermal decomposition oxidation to 450 ° C., SiO 2
_{The second} surface coat layer 37 is formed.

Next, an ink jet recording apparatus equipped with an ink jet head which is a droplet discharge head according to the present invention will be briefly described with reference to FIGS. FIG. 12 is a schematic perspective view of the mechanism of the recording apparatus, and FIG. 13 is a side view of the mechanism.

In this ink jet recording apparatus, a printing mechanism 82 and the like are housed inside a recording apparatus main body 81, and a paper feed cassette 84 capable of loading a large number of sheets 83 from the front side is provided below the apparatus main body 81. The paper tray 83 for manually feeding the paper 83 can be opened and removed, and the paper 83 fed from the paper feed cassette 84 or the manual tray 85 can be taken in. After the required image is recorded by the printing mechanism 82,
The paper is discharged to a paper discharge tray 86 mounted on the rear side.

The printing mechanism 82 holds a carriage 93 slidably in the main scanning direction by a main guide rod 91 and a sub guide rod 92 which are guide members which are laterally mounted on left and right side plates (not shown). Include yellow (Y), cyan (C), magenta (M), and black (B
k) a head 94 composed of an ink jet head, which is a droplet discharge head according to the present invention that discharges ink droplets of each color.
Are mounted with the ink droplet ejection direction facing downward, and on the upper side of the carriage 93, ink tanks (ink cartridges) 95 for supplying ink of each color to the head 94 are exchangeably mounted. The ink is supplied from the ink cartridge 95 into the head 94 through the ink supply hole 18.

Here, the carriage 93 is slidably fitted on the main guide rod 91 on the rear side (downstream side in the paper transport direction) and on the front guide rod 9 on the front side (upstream side in the paper transport direction).
2 slidably mounted. The carriage 93 is moved and scanned in the main scanning direction.
A timing belt 100 is stretched between a driving pulley 98 and a driven pulley 99 which are driven to rotate by the driving unit 7, and the timing belt 100 is fixed to a carriage 93. Although the heads 94 of the respective colors are used as the recording heads here, one having a nozzle for ejecting ink droplets of the respective colors is used.
Individual heads may be used.

On the other hand, in order to transport the paper 83 set in the paper feed cassette 84 to the lower side of the head 94, a paper feed roller 101 that separates and feeds the paper 83 from the paper feed cassette 84.
And a friction member 102, a guide member 103 for guiding the paper 83, a transport roller 104 for inverting and transporting the fed paper 83, a transport roller 105 and a transport roller 1 pressed against the peripheral surface of the transport roller 104.
And a tip roller 106 for defining an angle at which the sheet 83 is fed from the sheet 04. The transport roller 104 is driven to rotate by a sub-scanning motor 107 via a gear train.

Further, there is provided a printing receiving member 109 which is a paper guide member for guiding the paper 83 sent out from the transport roller 104 below the recording head 94 corresponding to the moving range of the carriage 93 in the main scanning direction. I have. On the downstream side of the printing receiving member 109 in the sheet conveying direction, a conveying roller 11 that is rotationally driven to send out the sheet 83 in the sheet discharging direction.
1. A spur 112 is provided, and the paper 83
The paper discharge rollers 113 and spurs 114 that feed the paper to the paper 6 and guide members 115 and 116 that form a paper discharge path are provided.

A reliability maintenance / recovery mechanism (hereinafter, referred to as a “subsystem”) 117 for maintaining and recovering the reliability of the head 94 is disposed on the right end side in the moving direction of the carriage 93. The carriage 93 is moved to the subsystem 117 side during standby for printing, and the head 94 is capped by capping means or the like.

In each of the above embodiments, an example in which the droplet discharge head and the microactuator according to the present invention are applied to an electrostatic ink jet head has been described. However, the present invention is not limited to this. The present invention can be applied to a droplet discharge head that discharges a droplet, for example, a liquid resist for patterning, or can be applied to a micromotor, an actuator portion of a micropump, or the like as a microactuator.

The droplet discharge head has been described as a side shooter system in which the diaphragm displacement direction and the nozzle droplet discharge direction are the same. However, a side shooter system in which the diaphragm displacement direction and the nozzle droplet discharge direction are orthogonal to each other. You can also.

Further, in each of the above-described embodiments, an example using a glass substrate has been described. However, a silicon substrate or a combination of a glass substrate and a silicon substrate may be used as the first substrate. Further, in the above embodiment, the top plate is formed of the third glass substrate, but the nozzle and the like are made of another material, for example, a laminated member of a metal layer such as Fernico and Kovar and a resin, or two or more types of metal. Layered members,
Alternatively, it can be formed of a single-layer member or the like. Furthermore, although the inclined region of the electrode has a linear inclination, it may have a curved inclination.

[0073]

As described above, according to the droplet discharge head of the present invention, since the liquid chamber is formed by the sand blast method, the time required for forming the liquid chamber is formed by etching. As compared with the case, it is possible to greatly reduce the cost and reduce the cost of the head.

Here, by smoothing the blast surface of the liquid chamber, the liquid flowability is not hindered and the reliability is improved. In this case, the blast surface of the liquid chamber is smoothed by stepwise sandblasting using abrasive grains of two or more types of sandblasts, so that a smooth process can be performed. In addition, by smoothing by etching, flatness is easily improved. Furthermore, smoothing by using an annealing process facilitates the smoothing process when a glass substrate is used. Furthermore, by forming and smoothing the surface coat layer, the planar accuracy is further improved, and the reliability is also improved.

Further, the cost can be further reduced by using a glass substrate as a member for forming the liquid chamber. In this case, the cost is further reduced by joining the glass substrate forming the liquid chamber and the glass substrate provided with the electrode facing the diaphragm by anodic bonding, which has a diaphragm forming the wall surface of the liquid chamber. Can be achieved.

Further, by forming a water-repellent film containing polysilazane on the surface of the member forming the nozzle, the water-repellent film can be formed by a simple process to reduce the cost. In this case, the water repellency of the surface of the water repellent film containing polysilazane is improved by removing silicon oxide containing hydroxyl groups.

According to the method for manufacturing a droplet discharge head according to the present invention, the method for manufacturing a droplet discharge head according to the present invention, wherein the diameter of abrasive grains used in sandblasting is 3 to 15 μm
Since m and hardness are 9 to 13 in Mohs hardness, high-speed and high-precision cutting can be performed. Here, in the sandblasting method, by masking with a mask in which a plurality of types of flow path patterns are formed,
The time required for forming the flow path is reduced, and the cost can be reduced.

The ink jet recording apparatus according to the present invention
Since the inkjet head is configured as the droplet discharge head according to the present invention, the cost of the recording apparatus can be reduced.

According to the microactuator of the present invention, the microactuator has the first member provided with the diaphragm and the second member provided with the electrode facing the diaphragm, and the concave portion corresponding to the diaphragm of the first member is provided. Since the structure is formed by the sandblasting method, a low-cost microactuator can be obtained. Here, since both the first member and the second member are made of glass members and are anodically bonded, the cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view in a longitudinal direction of a diaphragm of an inkjet head according to a first embodiment of the present invention.

FIG. 2 is an explanatory cross-sectional view of the head in a lateral direction of a diaphragm.

FIG. 3 is an explanatory plan view of a flow path pattern of the head.

FIG. 4 is an explanatory diagram for explaining a manufacturing process of a first glass substrate of the head.

FIG. 5 is an explanatory diagram illustrating an example of a relationship between a mask opening for blasting and a processing depth.

FIG. 6 is an explanatory view for explaining an example of the relationship between the abrasive grain size of blasting and the size of chipping.

FIG. 7 is an SEM photograph for explaining a state when sand blasting is performed on a glass substrate.

FIG. 8 is an explanatory diagram for explaining a manufacturing process of a first glass substrate in an inkjet head according to a second embodiment of the present invention.

FIG. 9 is an explanatory diagram for explaining a manufacturing process of a first glass substrate in an inkjet head according to a third embodiment of the present invention.

FIG. 10 is an explanatory cross-sectional view in a longitudinal direction of a diaphragm of an inkjet head according to a fourth embodiment of the present invention.

FIG. 11 is an explanatory cross-sectional view of the head in the transverse direction of the diaphragm.

FIG. 12 is a schematic perspective explanatory view of a mechanism section of the inkjet recording apparatus according to the present invention.

FIG. 13 is an explanatory side view of the mechanism.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 1st glass substrate, 2 ... 2nd glass substrate, 3 ... 3rd glass substrate, 4 ... Nozzle, 6 ... Liquid chamber, 7 ... Fluid resistance part, 8
... common ink chamber, 12 ... diaphragm, 15 ... electrodes, 20 ... water-repellent film

Claims (15)

[Claims] 1. A droplet discharge head for discharging a droplet from a nozzle by pressurizing a liquid in a liquid chamber to which the nozzle communicates, wherein the liquid chamber is formed by a sand blast method. . 2. The droplet discharge head according to claim 1, wherein a blast surface of the liquid chamber is smoothed. 3. The droplet discharge head according to claim 2, wherein the blast surface of the liquid chamber is smoothed by sandblasting using two or more types of sandblast abrasive grains in a stepwise manner. Droplet discharge head. 4. The droplet discharge head according to claim 2, wherein a blast surface of the liquid chamber is smoothed by etching. 5. The droplet discharge head according to claim 2, wherein a blast surface of the liquid chamber is smoothed by an annealing process. 6. The droplet discharge head according to claim 2, wherein a blast surface of the liquid chamber is smoothed by forming a surface coat layer thereon. 7. The droplet discharge head according to claim 1, wherein a member forming the liquid chamber is a glass substrate. 8. The droplet discharge head according to claim 7, further comprising a diaphragm forming a wall surface of the liquid chamber, wherein a glass substrate having the liquid chamber formed thereon and an electrode facing the diaphragm are provided. A droplet discharge head, which is bonded to a glass substrate by anodic bonding. 9. The droplet discharge head according to claim 1, wherein a water-repellent film containing polysilazane is formed on a surface of a member forming the nozzle. Discharge head. 10. The droplet discharge head according to claim 9, wherein the surface of the water-repellent film containing polysilazane is free of silicon oxide containing a hydroxyl group. 11. The method for manufacturing a droplet discharge head according to claim 1, wherein the particle diameter is 3 to 1.
A method for manufacturing a droplet discharge head, wherein the liquid chamber is formed by sandblasting using abrasive grains having a Mohs hardness of 9 to 13 having a hardness of 5 μm. 12. The method of manufacturing a droplet discharge head according to claim 11, wherein said sandblasting method is performed by masking with a mask having a plurality of types of flow path patterns formed thereon. . 13. An ink jet recording apparatus equipped with an ink jet head for discharging ink droplets, wherein said ink jet head is the liquid drop discharging head according to any one of claims 1 to 10. . 14. A microactuator comprising: a first member provided with a diaphragm; and a second member provided with an electrode facing the diaphragm, wherein the microactuator deforms and displaces the diaphragm by electrostatic force. A microactuator characterized in that a concave portion corresponding to the diaphragm is formed on the member by a sandblast method. 15. The microactuator according to claim 14, wherein both the first member and the second member are made of a glass substrate and are bonded by anodic bonding.