JP2007253484A - Liquid jetting head, liquid jetting device, and manufacturing method for liquid jetting head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid jetting head or the like for which a water-repellent section such as a water-repellent film to the nozzle forming section of a nozzle plate or the like can precisely be formed without going through a complicated process. <P>SOLUTION: This liquid jetting head 100 has the nozzle forming section 331 for which a nozzle section 331a for discharging a liquid is formed. A water repellent film 334 is formed at the nozzle forming section including the nozzle section. By removing the water repellent film by a laser being cast by a laser section, the water-repellent section is formed at least on the liquid discharging surface of the nozzle forming section. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid ejecting head, a liquid ejecting apparatus, and a method for manufacturing a liquid ejecting head having a nozzle forming portion in which a nozzle portion for discharging a liquid is formed.

Conventionally, an ink jet recording apparatus is provided with an ink jet recording head for discharging ink. The ink jet recording apparatus includes a nozzle that is an opening for ejecting ink, and the nozzle is formed on a nozzle plate.
When ink is ejected from the nozzles, the ink adheres to the periphery of the nozzles of such a nozzle plate, and the adhered ink forms an ink reservoir on the nozzle plate. This ink reservoir causes a so-called “flight bend” in which the ink ejection direction is bent when ink is ejected from the nozzles, and causes a defect such as printing.
Therefore, a water-repellent film is formed on the surface of the nozzle plate so as to prevent ink accumulation (see, for example, Patent Document 1).
JP 2001-38913 A

However, when this water-repellent film is formed on the entire area inside the nozzle opening or on the inner side of the nozzle plate, that is, on the side where the ink is stored, the ink is discharged from the nozzle to the inside of the opening. It will be drawn deeply. At this time, bubbles are engulfed together with the ink, and there is a problem that the ejection direction varies during the subsequent ink ejection.
Therefore, in order to form a water-repellent film on the surface of the nozzle plate, it is necessary to perform the following steps.
That is, first, masking with a resist or the like is performed on the inside of the nozzle opening and the inside of the nozzle plate where the water-repellent coating should not be formed. Thereafter, a water repellent film is formed on the surface of the nozzle plate.
Next, by removing the masking resist and the like, a water repellent film is formed at a desired portion of the nozzle plate.
Thus, conventionally, since a complicated masking process is required, there has been a problem that the manufacturing cost for forming the water-repellent film increases.
Further, there is a portion where the ink forms a meniscus on the surface side of the nozzle plate inside the nozzle opening, and it is desirable that a water-repellent film is formed on this portion.
However, there is also a problem that it is difficult to control the water-repellent coating so as to leave only a part of the inside of the nozzle opening with high precision and evenly for all the nozzles.

  Therefore, the present invention provides a liquid ejecting head, a liquid ejecting apparatus, and a liquid that can accurately form a water repellent portion such as a water repellent film on a nozzle forming portion such as a nozzle plate without going through complicated steps. An object of the present invention is to provide a method for manufacturing an ejection head.

  According to the present invention, there is provided a liquid ejecting head having a nozzle forming portion in which a nozzle portion for discharging a liquid is formed, and forming a water repellent film on the nozzle forming portion including the nozzle portion The liquid ejecting head is characterized in that the water repellent film is formed at least on the liquid projecting surface of the nozzle forming portion by removing the water repellent film with a laser irradiated by the laser portion. Is done.

According to the above configuration, by forming the water repellent film on the nozzle forming portion including the nozzle portion and removing the water repellent film with the laser irradiated by the laser portion, at least the liquid projecting surface of the nozzle forming portion A water repellent part is formed. For this reason, the masking process is not required as in the conventional case, and the manufacturing cost of the liquid jet head can be reduced.
Further, since the water repellent part is removed by the laser of the laser part, the water repellent part can be formed with high accuracy.

  Preferably, the liquid ejecting head is characterized in that the water repellent portion is formed at least in the meniscus forming portion inside the nozzle portion.

According to the said structure, the water-repellent part is formed in the meniscus formation part inside the nozzle part at least. For this reason, the meniscus is easily formed satisfactorily.
Further, it has been difficult to control the water-repellent film to be left only on a part of the inside of the nozzle portion through a masking process as in the prior art. However, according to the said structure, since a water repellent film is removed with a laser, a water repellent film can be accurately left inside a nozzle part.

  Preferably, the water-repellent film is removed by changing a laser irradiation angle of the laser unit irradiated on the inside of the nozzle unit of the nozzle forming unit. A liquid ejecting head;

  According to the above configuration, the water repellent film is removed by changing the laser irradiation angle of the laser unit irradiated to the inside of the nozzle part of the nozzle forming unit. Even within the nozzle portion that is difficult to remove, the water repellent film can be easily and accurately removed.

  Preferably, the water-repellent part is exposed to the atmosphere after being irradiated with plasma or ultraviolet rays, and then is terminated with an OH group, and the surface is OH-grouped, and a metal alkoxide having a long-chain polymer group containing fluorine or And a molecular film having water repellency, such as a monomolecular film of a metal salt having a water repellent group.

  According to the above configuration, the water-repellent part is exposed to the atmosphere after being irradiated with plasma or ultraviolet rays, and is then terminated with an OH group, the surface layer is OH-grouped, and the metal has a long-chain polymer group containing fluorine. And a molecular film having water repellency such as a monomolecular film of a metal salt having an alkoxide or a water repellent group. For this reason, when a molecular film such as a metal alkoxide is formed on such an underlayer, the OH group and the molecular film of the metal alkoxide are bonded to form a water repellent portion with high density and high adhesion.

  According to the present invention, there is provided a liquid ejecting apparatus having a liquid ejecting head having a nozzle forming portion in which a nozzle portion for discharging liquid is formed, including the nozzle portion of the liquid ejecting head. By forming a water repellent film on the nozzle forming portion and removing the water repellent film with a laser irradiated by the laser portion, a water repellent portion is formed at least on the liquid projecting surface of the nozzle forming portion. This is achieved by the liquid ejecting apparatus.

  According to the present invention, there is provided a method for manufacturing a liquid ejecting head having a nozzle forming portion in which a nozzle portion for discharging a liquid is formed, wherein the nozzle forming portion including the nozzle portion is water repellent. A liquid jet comprising: forming a film, and removing the water-repellent film with a laser irradiated by the laser unit, so that a water-repellent unit is formed at least on a liquid projecting surface of the nozzle forming unit. This is achieved by the head manufacturing method.

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
The embodiments described below are preferred specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise stated, the present invention is not limited to these embodiments.

FIG. 1 is a schematic perspective view showing an ink jet recording apparatus (hereinafter referred to as “recording apparatus”) 100 according to an embodiment of a liquid ejecting apparatus of the invention.
As shown in FIG. 1, the recording apparatus 100 includes a carriage 101. The carriage 101 is guided by a guide member 104 via a timing belt 103 driven by a carriage motor 102 and reciprocally moves in the axial direction of the platen 105. It is configured to be.

For example, an ink jet recording head (hereinafter referred to as “recording head”) 300, which is a liquid ejecting head described later, is mounted on the side of the carriage 101 facing the recording sheet 200 in FIG. For example, an ink cartridge 106 containing ink, which is liquid, is detachably loaded.
The recording paper 200 in FIG. 1 is arranged in a printing area and the like, and is configured such that ink is ejected by the recording head 300 and printing or the like is performed.

FIG. 2 is a schematic perspective view of the recording head 300. As shown in FIG. 2, the recording head 300 has a case 310. The case 310 is a resin member having a block-shaped case main body 311 and a flange portion 312 extending laterally from the base end portion of the case main body 311.
Inside the case 310, a vibrator unit 320 is arranged as shown in FIG. As shown in FIG. 2, the vibrator unit 320 includes a piezoelectric vibrator 321 that expands and contracts in the vertical direction (longitudinal vibration type) in the figure when a voltage is applied. The piezoelectric vibrator 321 includes a fixed plate 322 and a flexible cable 323. It is arranged to be sandwiched between.

FIG. 3 is a schematic cross-sectional view showing the relationship between the piezoelectric vibrator 321 and the fixed plate 322, the case 310, and the like.
As shown in FIG. 3, the piezoelectric vibrator 321 is fixed to the fixed plate 322, and the fixed plate 322 is bonded to the fixed plate bonding portion 311 a of the case 310.

  In addition, a flow path unit 330 is disposed below the case 310 in FIG. As shown in FIG. 3, the flow path unit 330 is a nozzle part for discharging ink, for example, a stainless steel (SUS) nozzle forming part in which a plurality of nozzles 331a are formed. For example, the nozzle plate 331, An elastic plate 333 and a pressure chamber 332 are provided.

That is, the flow path unit 330 has an elastic plate 333, and a portion sandwiched between the elastic plate 333 and the nozzle plate 331 becomes the pressure chamber 332. The pressure chamber 332 contains ink. Therefore, when a voltage is applied to the piezoelectric vibrator 321 and the piezoelectric vibrator 321 is extended, the elastic plate 333 is deformed inward, the pressure in the pressure chamber 332 is increased, and ink is ejected from the nozzle 331a. ing.
FIG. 4 is a schematic cross-sectional view showing the nozzle plate 331, the nozzle 331a, and the like.
As shown in FIG. 4, for example, on the recording paper 200 side of FIG. 1 of the nozzle plate 331 (lower side in FIG. 4), which is the ink protruding surface of the nozzle plate 331, for example, a water repellent film. 334 is formed.
Therefore, even if the ink is ejected from the nozzle 331a to the recording paper 200 and the ejected ink rebounds from the recording paper 200 and adheres to the lower surface side of the nozzle plate 331 in FIG. Therefore, no ink pool occurs.
Therefore, after that, when ink is ejected from the nozzle 331a, the ink ejection direction is bent, and it is possible to prevent printing defects and the like from occurring.

The water repellent film 334 is also formed on a part of the nozzle 331a. That is, the water repellent film 334 disposed on the lower surface side in FIG. 4 is formed so as to be connected to the inside of the opening of the nozzle 331a.
Thereby, a meniscus M formed by the ink in the nozzle 331a is formed corresponding to the formation position of the water repellent film 334 disposed inside the nozzle 331a.
Therefore, good printing characteristics can be obtained by forming the water repellent film 334 in the nozzle 331a evenly over all the nozzles 331a.
Further, it is possible to increase the printing speed by applying water repellent treatment to the inside of the nozzle 331a over a predetermined length.
Here, the meniscus M indicates a state in which the ink inside the nozzle 331a can be satisfactorily protruded, and indicates a state in which the liquid surface in the nozzle 331a is formed in a mountain shape as shown in FIG.

As shown in FIG. 4, the water-repellent film 334 is disposed on the lower surface side of the nozzle plate 331 and on the portion corresponding to the meniscus M forming portion in the opening of the nozzle 331a, and the nozzle plate 331 has the flow channel unit 330 side. Is not placed.
Thereby, when ink is drawn after the ink is discharged from the nozzle 331a, it can be prevented that the ink is largely drawn into the flow path unit 330 side.
By the way, in this way, when the ink is largely drawn, air bubbles are often drawn into the flow path unit 330. When the bubbles are drawn, there is a problem in that the ink ejection direction varies during the subsequent ejection of the ink from the nozzle 331a.
In this respect, in this embodiment, since ink is largely prevented from being drawn from the nozzle 331a, it is possible to avoid drawing of bubbles and to prevent ink ejection failure.

In addition, the water repellent film 334 in this embodiment includes a base layer that terminates with OH groups and OH groups the surface by being exposed to the atmosphere after being irradiated with plasma or ultraviolet rays. The underlayer is, for example, appropriately selected from a plasma polymerized film of silicone material, SiO ₂ , ZnO, NiO, SnO ₂ , AlO ₃ , ZrO ₂ , copper oxide, silver oxide, chromium oxide, or iron oxide. Applied.
The water repellent film 334 includes a molecular film. The molecular film has water repellency such as a metal alkoxide having a long-chain polymer group containing fluorine or a monomolecular film of a metal salt having a water repellent group.
Therefore, the surface of the underlayer is oxidized and hydrogenated. Specifically, after being exposed to the atmosphere after plasma or ultraviolet irradiation, it is terminated with an OH group, and the surface is converted into an OH substrate. When the metal alkoxide molecular film is formed, the OH group of the base layer and the metal alkoxide molecular film are bonded to form a metal alkoxide water-repellent film 334 having high density and high adhesion.

In the water-repellent film 334 thus formed, the molecular film is in a high density state, and it is difficult for ink to penetrate into the molecular film. For this reason, excellent water repellency can be maintained and water repellency can be maintained over a long period of time. Moreover, since such a water-repellent film 34 is high-density, it is excellent also in abrasion resistance.
Therefore, in the nozzle plate 331 provided with such a water-repellent film 334, even if ink ejected from the nozzle 331a adheres, it is possible to more reliably prevent ink pooling. In addition, since the water repellency is maintained for a long time, the nozzle plate 331 does not deteriorate the water repellency even when used for a long time.

The recording apparatus 100 according to the present embodiment is configured as described above. The main manufacturing method will be described below.
FIGS. 5A and 5B are schematic views showing main steps for forming the water repellent film 334 on the nozzle plate 331 of FIG.
When the water repellent film 334 is formed on the nozzle plate 331, the nozzle plate 331 is disposed in a film forming apparatus (not shown), and the water repellent film 334 is formed on the entire surface of the nozzle plate 331. Specifically, as shown in FIG. 5A, a water repellent film 334 is formed on the entire surface of the nozzle plate 331 including the nozzle 331a.

Next, the water-repellent film 334 shown by oblique lines in FIG. 5B is removed by irradiating a laser part such as a YAG laser or an excimer laser having a wavelength that is absorbed by the water-repellent film 334. At this time, the laser power is, for example, 2.0 W or less, and the scan speed is, for example, 500 m / s to 200 m / s.
At this time, a laser such as a YAG laser irradiated to the inside of the opening of the nozzle 331a of the nozzle plate 331 has an irradiation angle, and the irradiation angle is changed. And by changing the irradiation angle in this way, it is possible to form the water repellent region in the nozzle 331a with high accuracy.
Specifically, as shown in FIG. 5B, the irradiation angle θ is appropriately determined for the virtual line I provided in the nozzle 331a, the irradiation angle is changed, and the laser is irradiated. As shown in FIG. 4, the water-repellent film 334 can form the water-repellent region in the nozzle 331a with high accuracy.
As described above, in this embodiment, since the unnecessary water-repellent film 334 is removed by the laser, a conventional masking process or the like is not necessary, and the recording apparatus 100 can be manufactured at low cost.
That is, the water repellent film 334 can be left easily and accurately by changing the laser irradiation angle θ even in the opening of the nozzle 331a in which it has conventionally been difficult to form a water repellent region uniformly.

  The present invention is not limited to the above-described embodiment. The present invention is not limited to an ink jet recording apparatus, but a recording head used in an image recording apparatus such as a printer, a color material ejecting head used in manufacturing a color filter such as a liquid crystal display, an organic EL display, and an FED (surface emitting) Electrode material ejecting heads used for electrode formation such as displays), liquid ejecting apparatuses using liquid ejecting heads for ejecting liquids such as bioorganic ejecting heads used for biochip manufacturing, sample ejecting apparatuses as precision pipettes, etc. Applicable.

1 is a schematic perspective view illustrating an ink jet recording apparatus according to an embodiment of a liquid ejecting apparatus of the invention. It is a schematic perspective view of a recording head. It is a schematic sectional drawing which shows the relationship between a piezoelectric vibrator, a fixed plate, and a case. It is a schematic sectional drawing which shows a nozzle plate and a nozzle. It is the schematic which shows the main processes which form a water repellent film in the nozzle plate of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Inkjet recording apparatus, 101 ... Carriage, 102 ... Carriage motor, 103 ... Timing belt, 104 ... Guide member, 105 ... Platen, 106 ... Ink cartridge, 200 ... Recording paper, 300 ... Inkjet recording head, 320 ... Vibrator unit, 321 ... Piezoelectric vibrator, 322 ... Fixed plate, 323 ... Flexible cable, 330 ... Flow Path unit, 331 ... Nozzle plate, 331a ... Nozzle, 332 ... Pressure chamber, 333 ... Elastic plate, 334 ... Water-repellent film, M ... Meniscus, I ... Virtual line , Θ ... Irradiation angle

Claims (6)

A liquid ejecting head having a nozzle forming part in which a nozzle part for discharging liquid is formed,
Forming a water repellent film on the nozzle forming portion including the nozzle portion;
A liquid ejecting head, wherein a water repellent part is formed at least on a liquid projecting surface of the nozzle forming part by removing the water repellent film with a laser irradiated by a laser part.   The liquid ejecting head according to claim 1, wherein the water-repellent portion is formed at least in a meniscus forming portion inside the nozzle portion.   2. The water-repellent film is removed by changing a laser irradiation angle of the laser unit irradiated to the inside of the nozzle unit of the nozzle forming unit. Alternatively, the liquid ejecting head according to claim 2. The water repellent part is
An underlayer that terminates with OH groups and OH-groups the surface by exposure to the atmosphere after plasma or ultraviolet irradiation;
And a molecular film having water repellency such as a monomolecular film of a metal alkoxide having a long-chain polymer group containing fluorine or a metal acid salt having a water repellent group. The liquid jet head according to any one of the above. A liquid ejecting apparatus having a liquid ejecting head having a nozzle forming portion in which a nozzle portion for discharging liquid is formed,
Forming a water repellent film on the nozzle forming portion including the nozzle portion of the liquid jet head;
A liquid ejecting apparatus, wherein a water repellent part is formed at least on a liquid projecting surface of the nozzle forming part by removing the water repellent film with a laser irradiated by a laser part. A method for manufacturing a liquid jet head having a nozzle forming portion in which a nozzle portion for discharging liquid is formed,
Forming a water repellent film on the nozzle forming portion including the nozzle portion;
A method of manufacturing a liquid ejecting head, wherein a water repellent part is formed at least on a liquid projecting surface of the nozzle forming part by removing the water repellent film with a laser irradiated by a laser part.

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