JPH07304176A - Manufacture of nozzle plate - Google Patents

Abstract

PURPOSE:To provide a manufacturing method for a nozzle plate which can jet ink in a good manner. CONSTITUTION:First, water-repellent films 2 are formed on one face of a base 1. Then the nozzle processing is carried out by forming an image on the base 1 of a nozzle plate 3 by applying excimer laser beam. Then sections except the water-repellent films 2 of the nozzle plate 3 on which nozzle processing is already applied are processed and turned to be hydrophilic. Sodium hydroxide 8 of 0.1 specification is heated up to 60 deg. to 90 deg.C, and the nozzle plate 3 is immersed for one minute and released, and then cleaned by pure water and dried by hot air. After the above treatment, hydrophilic degree is checked by the contact angle of pure water, and it is found by the checking that the treatment shows 15 deg. according to the above arrangement, which means sufficiently hydrophilic, while untreated polyimide shows 64 deg..

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a nozzle plate having a substrate on which nozzles for ejecting ink are formed and a water-repellent film formed on the substrate around the positions where the nozzles are formed. It is about.

[0002]

2. Description of the Related Art In a head for ejecting ink, there is a problem that when the ink is wetted on the peripheral surface of the nozzle, a deviation occurs in the flight direction of the ink droplet, and when the wetness becomes severe, the ink droplet does not fly. To solve such a problem, Japanese Patent Laid-Open No. 55-65564 or Japanese Patent Laid-Open No.
Japanese Patent Laid-Open No. 55140 discloses a technique in which a water-repellent film is provided on the surface of a nozzle plate on which nozzles are formed to prevent the occurrence of wetting.

However, if the water-repellent liquid is applied to the surface of the plate after the nozzles are formed on the plate, a part of the water-repellent liquid will spread unevenly inside the nozzle or block the nozzle. As a result, the meniscus of the ink formed by the nozzles varies from nozzle to nozzle, which causes inconveniences such as variations in the ink ejection timing and no ink ejection.

For this reason, it has been considered to apply a water-repellent film on the surface of the nozzle plate after completely embedding the coating material inside the nozzle, but it is very important to completely embed the coating material inside the nozzle. Very difficult and impractical. From such a background, in Japanese Unexamined Patent Publication No. 2-187342, after a nozzle plate of an ink jet printer is provided with a water repellent film, the substrate of the nozzle plate and the water repellent film are simultaneously processed by an excimer laser or the like. A method of making the same is described. In this method for producing a nozzle plate, a dry film (SE-320 manufactured by Tokyo Ohka) is used for the nozzle plate, and a polyimide film is used for the water-repellent film.

[0005]

However, the portion of the nozzle plate on which the water-repellent film is formed, which comes into contact with the ink,
That is, on the inner surface of the nozzle and the back surface of the nozzle plate, if the wettability with ink is poor, bubbles may enter or be entrained during ink filling or ink ejection, and removal thereof is not easy.
If bubbles exist in the ink flow path, there is a problem that the energy for ejecting ink is absorbed and the ink is not ejected, or the ejection direction is not stable.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a method for manufacturing a nozzle plate which can eject ink well.

[0007]

In order to achieve this object, in a first aspect of the present invention, a substrate on which a nozzle for ejecting ink is formed and a substrate is formed around a position where the nozzle is formed. A method for manufacturing a nozzle plate having a water-repellent film, the method comprising: forming a water-repellent film on the substrate; forming the nozzle on the substrate having the water-repellent film formed thereon; And a step of hydrophilizing a portion in contact with the ink.

According to a second aspect of the present invention, the substrate is made of a polyimide resin, the water-repellent film is made of a fluorine-based material or a silicon-based material, and the hydrophilic treatment is performed by immersing the substrate in an alkaline solution for etching. It is characterized by doing.

According to a third aspect of the present invention, the substrate is made of a resin, the water-repellent film is made of a fluorine-based material or a silicon-based material, and the hydrophilic treatment is performed by immersing the substrate in a dye liquid and dyeing the dye. It is characterized in that the parts are attached and penetrated.

According to a fourth aspect of the present invention, in the hydrophilic treatment, fine solids are made to collide from the side of the substrate opposite to the surface on which the water repellent film is formed.

According to a fifth aspect of the present invention, the nozzle is processed by excimer laser light.

According to a sixth aspect of the present invention, when the nozzle is processed by the excimer laser beam, the lid-like member left without processing the water-repellent film is removed by the adhesive member.

According to a seventh aspect of the present invention, the burr of the water-repellent film generated at the time of processing the nozzle with the excimer laser light is melted by heating.

[0014]

According to the method of manufacturing a nozzle plate of the present invention having the above-described structure, a water-repellent film is formed on the substrate, the nozzle is formed on the substrate, and then hydrophilic treatment is applied to the ink on the substrate. The contact portion is made hydrophilic, the entry and entrainment of air bubbles is prevented, and the ink droplets are ejected with a uniform ejection direction and a stable flight speed.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of the nozzle plate 3.
The nozzle plate 3 has the water-repellent film 2 formed on one surface of the substrate 1, and the substrate 1 is a material having solvent resistance to the solvent contained in the used ink components. In this case, polyimide resin is used. Regarding the polyimide resin, it has no melting point and is extremely excellent in thermal characteristics.

The water-repellent film 2 is a tetrafluoroethylene-6-fluoropropylene copolymer resin (hereinafter referred to as FE) in this embodiment.
P resin) is applied to form a film having a thickness of about 1 μm. Here, the softening point (melting point) of the FEP resin is 250 ° C.
~ 280 ° C.

At this time, the surface or the whole surface of the substrate 1 to which the water-repellent liquid is applied is subjected to a blast process or the like in which a minute solid is made to collide, and a fine concavo-convex forming process is performed to thereby form the substrate 1 of the water-repellent film 2. It is desirable to increase the adhesion to the.

In the present embodiment, the blasting method was used for forming the unevenness, but it is also possible to form the unevenness by chemical etching with a solvent or the like.

Next, as shown in FIG.
The excimer laser beam 11 emitted from the laser beam No. 4 is passed through a mask 12 similar to a desired processing shape, and the lens shape is imaged on the substrate 1 of the nozzle plate 3 by the lens 13 to perform nozzle processing. Here, in this embodiment, the excimer laser beam 11 is a KrF excimer laser beam having a wavelength of 248 nm. Further, the mask 12 and the lens 13 are appropriately set depending on the nozzle shape, laser processing conditions, and the like. In this embodiment, a 1/5 reduction lens 13 and a mask 12 having a hole with a diameter of 300 μm are used.

The burr 4 of the water-repellent film 2 is formed in the vicinity of the injection port of the nozzle 6 obtained by this processing as shown in FIG.
Alternatively, the water-repellent film 2 may remain as a lid shape (see FIG. 3) without being processed.

As shown in FIG. 3, the lid-shaped portion of the water-repellent film 2 that is left unprocessed, that is, the lid 5, is obtained by bringing the adhesive sheet 7 into contact with the water-repellent film 2 and the lid 5 (see FIG. 3).
(B)) After that, the sheet 7 can be easily removed by peeling it off (FIG. 3C).

In this embodiment, such a method is used,
For example, the same effect can be obtained by adhering the adhesive sheet 7 to the surface of the water-repellent film 2 in advance before the excimer laser processing, and then peeling it off.

Next, even if the lid 5 is removed as described above, a small burr remains, so thermal processing is performed to remove the burr 4. That is, in order to soften and melt the burrs 4 to eliminate them, the burrs 4 were left at a temperature of 300 ° C. for 1 hour.
As a result, as shown in FIG. 4, the burr 4 of the water-repellent film 2 is softened and the nozzle 6 without the burr 4 is formed. In the present embodiment, the heat treatment temperature was set to 300 ° C. in consideration of the melting temperature of the applied FEP resin. However, when the treatment temperature is considerably higher than the melting temperature of the water repellent film 2, the water repellent film 2 is provided with the nozzle 6.
Be careful of temperature control as it may flow into the interior.

In the present embodiment, burrs and the like that adversely affect the jetting after nozzle processing were formed, so processing was performed to remove such burrs and the like, but other processing methods and other water repellent films were used. When the formation of burrs or the like is prevented by using the above method, it is not necessary to perform such treatment.

Next, as shown in FIG. 5, a portion of the nozzle plate 3 which has been subjected to the nozzle processing except the water-repellent film 2 is subjected to a hydrophilic treatment. As a method for making the polyimide resin hydrophilic, there is a method of immersing it in an alkaline solution. In this embodiment,
For example, 0.1N sodium hydroxide aqueous solution 8 at 60 ℃
To 90 ° C., the nozzle plate 3 was immersed for 1 minute and taken out, then washed with pure water and dried with warm air. In this treatment, the substrate 1 made of polyimide is made hydrophilic, but the water-repellent film 2 which is not attacked by the alkaline solution is not made hydrophilic. After the treatment, the degree of hydrophilization was examined by the contact angle of pure water, and it was 64 ° for the substrate 1 not treated, whereas it was 15 ° after the treatment of this example, which is sufficient. It was confirmed that the film was hydrophilized. In addition, since this process is performed after performing the nozzle processing, the inside of the nozzle 6 is also made hydrophilic.

In this embodiment, since the substrate 1 is polyimide, the treatment is performed with an alkaline solution. However, depending on the material of the substrate 1, acid treatment, plasma treatment, flame treatment, solvent treatment or the like is also effective. Alternatively, the nozzle plate may be immersed in an aqueous dye solution and heated to adsorb or permeate the dye in advance on the liquid contact surface to improve the wettability of the liquid contact surface.

Nozzle plate 3 thus obtained
As a result of producing an ink jet head by using, and jetting ink, the jet side surface of the nozzle plate is treated to be water repellent, and the inner surface of the nozzle 6 of the nozzle plate 3 and the ink channel side surface are made hydrophilic. It was confirmed that the entrainment of bubbles was prevented, and the ink droplets were ejected with a uniform flight direction and a stable flight speed. Further, even if bubbles were generated in the ink flow path, they could be easily removed.

Further, in this embodiment, since the nozzle processing is performed after the water-repellent film 2 is formed on the nozzle plate 3, the nozzle 6 is not blocked by the water-repellent liquid.
Furthermore, since nozzle processing is performed and the nozzle plate subjected to hydrophilic treatment is assembled to the inkjet head main body, hydrophilic treatment can be performed on a nozzle plate substrate basis,
Therefore, the processing method is not complicated and the processing cost is low.

In this embodiment, the water-repellent film 2 was formed of tetrafluoroethylene-6-fluoropropene copolymer resin (FEP resin), but polytetrafluoroethylene resin (PTFE resin) is also used. ) Tetrafluoroethylene-perfluoroalkoxyethylene copolymer resin (PFA resin), trifluoroethylene chloride resin (PCTFE resin), tetrafluoroethylene-ethylene copolymer resin (ETFE resin), vinylidene fluoride resin, fluorine Fluorine resin such as vinyl chloride resin,
Furthermore, surface modifiers and coating materials containing fluorine atoms such as CYTOP (trade name: Asahi Glass), KP801
M (trade name: Shin-Etsu Chemical), AF1600 (trade name: DuPont), DEFENSA77702 (photoradical polymerization resin: Dainippon Ink and Chemicals), FS-116 (trade name: Daikin), Florard (trade name: Sumitomo 3M) You may form a water-repellent film. The fluorine-based resin, the surface modifier containing a fluorine atom, and the coating material are particularly excellent in water repellency and solvent resistance to an ink solvent. In addition, depending on the ink solvent used, there is no problem even if the water-repellent film is formed of a silicone resin or the like.

In this embodiment, the substrate 1 is made of polyimide resin. However, when the above-mentioned deburring after nozzle processing is carried out by a thermal processing method, a thermosetting resin or a water repellent film having a softening temperature is used. If the resin used is relatively higher than the material used as 2, there is no problem. If a burr-free processing method other than the thermal processing method or a processing method without burr is used, heat treatment is not performed. Any resin may be used as long as it is not affected by the ink used.

Further, in the present embodiment, the excimer laser processing is used for the nozzle processing, but for example punching processing or drill processing may be used. In this case, the substrate 1 is a material that can be processed by these processes, and for example, a metal material can be used.

Although a flat plate is used as the substrate in this embodiment, it may be a base material having a flat surface and a concave portion to be a nozzle formed on the back surface by injection molding or the like.

Further, in this embodiment, the water-repellent film 2 is formed on the entire surface of the substrate 1, but the water-repellent film may be formed only on the portion of the substrate 1 where the nozzles are formed.

In this embodiment, the water repellent film 2 on the substrate 1 is also used.
The nozzle is formed by irradiating the excimer laser beam 11 having a desired shape with the mask 12 from the back side of the surface on which the nozzle is formed. However, the nozzle may be formed by using a contact mask. The nozzle may be formed by irradiating the excimer laser beam from the water repellent film side.

[0036]

As is apparent from the above description, according to the method for manufacturing a nozzle plate of the present invention, the water-repellent film is formed on the substrate, and the nozzle is formed on the substrate. Is not blocked by the water repellent film. In addition, since the hydrophilic treatment is performed after forming the nozzle, the portion of the substrate that is in contact with the ink is made hydrophilic. For this reason, it is possible to prevent bubbles from entering and engulfing, it is easy to remove the bubbles in the ink flow path from the nozzle, and it is possible to eject the ink droplets having a uniform ejection direction and a stable flight speed. Further, since the hydrophilic treatment can be performed for each nozzle plate substrate, the treatment cost is low.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a nozzle plate according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing nozzle processing of the present embodiment.

FIG. 3 is an explanatory diagram showing removal of a water-repellent film remaining during the nozzle processing of the present embodiment.

FIG. 4 is a cross-sectional view showing a nozzle portion obtained according to the present embodiment.

FIG. 5 is an explanatory diagram showing the hydrophilic treatment of the present embodiment.

[Explanation of symbols]

 1 substrate 2 water-repellent film 3 nozzle plate 6 nozzle 8 sodium hydroxide aqueous solution 11 excimer laser light

Claims (7)

[Claims] 1. A method of manufacturing a nozzle plate, comprising: a substrate on which nozzles for ejecting ink are formed; and a water-repellent film formed around a position of the substrate on which the nozzles are formed. A step of forming a water-repellent film on the substrate, a step of forming the nozzle on the substrate on which the water-repellent film is formed, and a step of hydrophilizing a portion of the substrate in contact with ink. Nozzle plate manufacturing method. 2. The substrate is formed of a polyimide resin, the water-repellent film is formed of a fluorine-based or silicon-based material, and the hydrophilic treatment is performed by immersing the substrate in an alkaline solution and etching the substrate. The method of manufacturing a nozzle plate according to claim 1, wherein the nozzle plate is manufactured. 3. The substrate is formed of a resin, the water-repellent film is formed of a fluorine-based or silicon-based material, and the hydrophilic treatment is performed by immersing the substrate in a dye liquid to attach a part of the dye. The method of manufacturing a nozzle plate according to claim 1, wherein the nozzle plate is permeated. 4. The hydrophilic treatment is performed on the substrate,
The method for manufacturing a nozzle plate according to claim 1, wherein fine solids are made to collide from the side opposite to the surface on which the water repellent film is formed. 5. The method of manufacturing a nozzle plate according to claim 1, wherein the nozzle is processed by excimer laser light. 6. The method for manufacturing a nozzle plate according to claim 5, wherein the lid-like member left without processing the water-repellent film is removed by an adhesive member when the nozzle is processed by the excimer laser light. 7. The method of manufacturing a nozzle plate according to claim 5, wherein the burr of the water-repellent film generated at the time of processing the nozzle by the excimer laser light is melted by heating.