JP2002210984A - Nozzle forming member, liquid drop ejection head, and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that the ejecting direction of liquid drops becomes irregular. SOLUTION: A nozzle plate 43 comprises an organic resin member 71 and a high rigidity member 72 laid in layer wherein a water repellent film 74 is formed on the surface of the organic resin member 71 by spraying mist of a water repellent agent thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle forming member, a droplet discharge head and a method of manufacturing the same.

[0002]

2. Description of the Related Art An ink jet head used in an image recording apparatus such as a printer, a facsimile, and a copying apparatus or an ink jet recording apparatus used as an image forming apparatus includes a nozzle for discharging ink droplets, a pressurizing chamber communicating with the nozzle, (Also referred to as an ink flow path, a pressurized liquid chamber, a pressure chamber, a discharge chamber, a liquid chamber, etc.), and an electromechanical transducer such as a piezoelectric element for pressurizing the ink in the pressurized chamber, or an electric heater such as a heater. A conversion element or a vibration plate forming a wall surface of an ink flow path and an energy generation means including an electrode opposed thereto are provided. Discharge the droplet.

[0003] Here, as a nozzle forming member in which a nozzle is formed, Japanese Patent Application Laid-Open Nos.
No. 12,1842, etc., a plate made of an organic resin material having holes (nozzle holes) serving as nozzles formed by an excimer laser, or disclosed in JP-A-63-3963, As described in Japanese Patent No. 42939, a resist pattern corresponding to the nozzle diameter is formed on an electroformed support substrate using a photosensitive resin material such as a dry film resist, and then nickel or the like is formed using the resist pattern. Is known in which a high rigid member is deposited by an electroforming method to form a nozzle plate.

However, it is difficult for such a single-layer nozzle forming member to realize all functions required for the nozzle, such as water repellency, high precision nozzle, and high rigidity.

Therefore, as described in Japanese Patent Application Laid-Open No. 8-34119, a nozzle plate base having a polymer layer laminated with an epoxy adhesive on a metal layer in which nozzle holes are formed in advance by an electroforming method is used. There is also known an excimer laser in which a hole portion communicating with a nozzle hole is formed in a polymer layer. Further, as described in Japanese Patent Application Laid-Open No. 6-314704, there is a stainless steel sheet in which nozzle holes are formed by press working, and the back side of the stainless steel sheet is formed of two metal layers by nickel electroforming.

In an ink jet head,
Since the recording is performed by ejecting ink droplets (ink droplets) from the nozzles, the shape and precision of the nozzles affect the ejection characteristics (ink droplet ejection performance) of the ink droplets, and the nozzle holes are formed. The characteristics of the surface of the nozzle forming member affect the ejection characteristics of the ink droplets. For example, when ink adheres to the periphery of the nozzle hole on the surface of the nozzle forming member and uneven ink accumulation (so-called uneven wetting) occurs, the ejection direction of the ink droplet is bent or the size of the ink droplet varies. It is known that inconveniences such as an unstable flying speed of ink droplets occur.

Therefore, in an ink jet head, as described in, for example, JP-A-4-294145, a nozzle formed by perforating a polymer material such as an electrolytic nickel nozzle, a press-perforated metal nozzle, or polycarbonate with an excimer laser. A water-repellent film such as a fluoropolymer coating film or a eutectoid plating film is formed on the surface of the member (discharge surface side surface) to impart ink repellency (water repellency) to the surface of the nozzle forming member. It has been practiced to improve the uniformity to stabilize the flight characteristics of ink droplets (for example, see JP-A-6-143587).

Further, a method has been proposed in which a water-repellent agent is coated on a nozzle forming member made of a resin member to form a water-repellent film, and a nozzle hole is formed in the water-repellent film together with the resin member by using an excimer laser. Japanese Unexamined Patent Publication No. Hei 10-3055582, Japanese Unexamined Patent Publication No. Hei 11-179918, Japanese Patent No. 2763
563, JP-A-6-87216, etc.).

[0009]

However, as described above, after forming a water-repellent film by coating a nozzle-forming member made of a resin material with a water-repellent agent, an excimer laser is applied to the resin member and the water-repellent film. When a nozzle hole is formed by using a water repellent, since the water repellent does not absorb excimer (ultraviolet) laser, it is impossible in principle to form a hole in the water repellent film with an excimer laser.

Therefore, it is necessary to add an ultraviolet absorber to the water repellent, or to use a fluorine bonding compound containing an ultraviolet absorbing resin member as the water repellent to enable drilling with an excimer laser. However, when an excimer laser is used to form a hole in a water-repellent film made of a water-repellent agent to which such an ultraviolet absorber is added or a water-repellent agent of a fluorine-bonding compound containing an ultraviolet-absorbing resin member, the end of the nozzle hole and the water-repellent film are not removed. There is a problem that the end portions of the film do not coincide with each other, the variation increases, the ink droplet ejection direction becomes irregular, and the image quality deteriorates.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a nozzle forming member excellent in droplet discharge characteristics, a droplet discharge head excellent in droplet discharge characteristics, and a method of manufacturing the same. The purpose is to do.

[0012]

In order to solve the above problems, a nozzle forming member according to the present invention comprises a resin member and a high-rigidity member laminated to form a water-repellent film on the surface of the resin member. In the member, the water-repellent film has a configuration in which a mist-formed water-repellent is attached to the surface of the resin member.

A nozzle forming member according to the present invention is a nozzle forming member in which a resin member and a high-rigidity member are laminated to form a water-repellent film on the surface of the resin member. This is a configuration in which a water film is formed. Here, the base film is preferably a metal oxide film or a film of a silane coupling material.

A nozzle forming member according to the present invention is a nozzle forming member in which a resin member and a highly rigid member are laminated to form a water repellent film on the surface of the resin member. Is formed on the surface of the resin member subjected to the above.

In each of the nozzle forming members according to the present invention, it is preferable that the resin member and the high-rigidity member are joined by an adhesive made of thermoplastic polyimide. Kovar, Fernico, SUS
It is preferable to use either a material or a copper material. further,
Preferably, the resin member is polyimide.

It is preferable that the water-repellent film contains fine particles of a solid fluorocarbon resin. Further, it is preferable that the water-repellent film contains a silane coupling material.

A nozzle forming member according to the present invention has a structure in which a resin member and a high-rigidity member are laminated with each other, and the resin member and the high-rigidity member are joined by an adhesive made of thermoplastic polyimide. Things.

A droplet discharge head according to the present invention includes a nozzle for discharging droplets, a pressurizing chamber communicating with the nozzle, and energy generating means for generating energy for pressurizing ink in the pressurizing chamber. The nozzle forming member having the nozzle formed therein is any one of the nozzle forming members according to the present invention.

A method of manufacturing a droplet discharge head according to the present invention is a method of manufacturing a droplet discharge head having a nozzle forming member in which a resin member and a highly rigid member are laminated and a water-repellent film is formed on the surface of the resin member. In the method, the water repellent is formed into a mist and adhered to the surface of the resin member to form a water repellent film.

Here, when forming the thin film, it is preferable to introduce a heated gas from the ink injection port of the head and eject it from the nozzle. Further, it is preferable to form a water-repellent film by adhering the water-repellent agent to the surface of the nozzle forming member of the heated head which is mist-formed.

Further, before forming the water-repellent film, it is preferable to form a metal oxide film or a silane coupling material film on the surface of the resin member of the head. Alternatively, it is preferable that the surface of the resin member of the head is exposed to plasma discharge before forming the water-repellent film.

[0022]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic perspective view of a mechanism of an ink jet recording apparatus equipped with an ink jet head which is a droplet discharge head according to the present invention, and FIG. 2 is a side view of the mechanism.

This ink jet recording apparatus includes a carriage movable in the main scanning direction inside a recording apparatus main body 1, a recording head including the inkjet head according to the present invention mounted on the carriage, and an ink cartridge for supplying ink to the recording head. And the like, and the paper 3 fed from the paper feed cassette 4 or the manual feed tray 5 is taken in, a required image is recorded by the printing mechanism 2, and then attached to the rear side. The paper is discharged to the discharged paper discharge tray 6.

The printing mechanism 2 slides the carriage 13 in the main scanning direction (the direction perpendicular to the paper surface in FIG. 2) by a main guide rod 11 and a sub guide rod 12 which are guide members which are laterally mounted on left and right side plates (not shown). This carriage 1
In No. 3, a head 14 composed of an ink jet head which is a liquid droplet discharging head for discharging ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk) is moved downward in the ink droplet discharging direction. Each ink tank (ink cartridge) 1 for supplying ink of each color to the head 14 is mounted above the carriage 13.
5 is exchangeably mounted.

Here, the carriage 13 is slidably fitted to the main guide rod 11 on the rear side (downstream side in the paper transport direction), and is slidably fitted on the front side (upstream side in the paper transport direction).
2 slidably mounted. The main scanning motor 1 is moved to scan the carriage 13 in the main scanning direction.
A timing belt 20 is stretched between a driving pulley 18 and a driven pulley 19, which are driven to rotate by 7, and the timing belt 20 is fixed to the carriage 13.

Although a head 14 of each color is used here as a recording head, a single head having a nozzle 4 for discharging ink droplets of each color may be used. Further, an ink jet head used as the head 14 is a piezo type that pressurizes ink through a vibration plate that forms a liquid chamber (ink flow path) wall with an electromechanical transducer such as a piezoelectric element,
Alternatively, a bubble type in which bubbles are generated by film boiling by a heating resistor to pressurize ink, or a diaphragm is displaced by electrostatic force between a diaphragm forming an ink flow path wall surface and an electrode opposed thereto. An electrostatic ink jet head that pressurizes ink can be used, but in this embodiment, an electrostatic ink jet head is used as described later.

On the other hand, the paper 3 set in the paper feed cassette 4
Roller 21 and a friction pad 22 for separating and feeding the paper 3 from the paper feed cassette 4 and a guide member 23 for guiding the paper 3
A transport roller 24 that reverses and transports the fed paper 3, a transport roller 25 that is pressed against the peripheral surface of the transport roller 24, and a tip roller 26 that defines an angle at which the paper 3 is fed from the transport roller 24. Is provided. The transport roller 24 is driven to rotate by a sub-scanning motor 27 via a gear train.

An image receiving member 29 is provided as a paper guide member for guiding the paper 3 fed from the transport roller 24 below the recording head 14 in accordance with the moving range of the carriage 13 in the main scanning direction. I have. On the downstream side of the printing receiving member 29 in the sheet conveying direction, a conveying roller 31 and a spur 32, which are driven to rotate in order to send out the sheet 3 in the sheet discharging direction.
And a paper discharge roller 33 and a spur 34 for feeding the paper 3 to the paper discharge tray 6 and guide members 35 and 36 for forming a paper discharge path.

A reliability maintenance / recovery mechanism 37 for maintaining and recovering the reliability of the head 14 is disposed at the right end side in the moving direction of the carriage 13. The carriage 13 is moved toward the reliability maintenance / recovery mechanism 37 during the standby for printing, and the head 14 is capped by the capping means or the like.

Next, an example of an ink-jet head which is a droplet discharge head according to the present invention, which constitutes the head 14 of the ink-jet recording apparatus, will be described with reference to FIGS. 3 is an exploded perspective view of the head, FIG. 4 is a cross-sectional view of the head in the longitudinal direction of the diaphragm, FIG. 5 is an enlarged view of a main part of FIG. 4, and FIG. FIG.

The ink jet head 40 includes a flow path substrate 41 which is a first substrate using a silicon substrate such as a single crystal silicon substrate and an SOI substrate, and a silicon substrate provided under the flow path substrate 41, Pyrex ( (Registered trademark) an electrode substrate 42 as a second substrate using a glass substrate, a ceramic substrate, or the like, and a nozzle plate 43 as a nozzle forming member according to the present invention provided above the flow path substrate 41, and a plurality of inks. Nozzles 44 for discharging droplets, pressurizing chambers 46 which are flow paths communicating with the nozzles 44, and a common liquid which is a common flow path communicating with each pressurizing chamber 46 via a fluid resistance portion 47 also serving as an ink supply path. A chamber channel 48 and the like are formed.

A plurality of pressurizing chambers 46 with which the nozzles 44 communicate with the flow path substrate 41, and a diaphragm 50 serving as a bottom which is a wall surface of the pressurizing chamber 46 (also serves as an electrode. Good) is formed, and a penetrating part forming the common liquid chamber flow path 48 is formed.

In this case, for example, when a single crystal silicon substrate is used as the flow path substrate 41, boron is injected in advance to the diaphragm thickness to form a high-concentration boron layer serving as an etching stop layer. After bonding, the concave portion serving as the pressurizing chamber 46 is anisotropically etched using an etching solution such as a KOH aqueous solution, whereby the high-concentration boron layer serves as an etching stop layer and the diaphragm 50 is formed with high precision. Is done. When an SOI substrate in which an active layer substrate is bonded to a base substrate via an oxide film is used, the diaphragm 50 is formed using the active layer substrate.

An oxide film layer 42a is formed on the electrode substrate 42 by a thermal oxidation method using a single crystal silicon substrate.
An electrode forming groove 54 is formed in the oxide film layer 42a, an electrode 55 facing the diaphragm 50 is provided on the bottom surface of the electrode forming groove 54, and a gap 56 is formed between the diaphragm 50 and the electrode 55. The diaphragm 50 and the electrode 55 constitute an actuator unit.

The electrode 55 is provided as a connecting portion (electrode take-out portion) 55a which extends to the outside and is connected to a connecting means connected to an external driving circuit. On the surface of the electrode 55, an electrode protection film 57 made of an oxide-based insulating film such as a SiO ₂ film or a nitride-based insulating film such as a Si ₃ N ₄ film is formed. Note that, without forming the electrode protection film 57 on the surface of the electrode 55, or while forming the electrode protection film 57 on the surface of the electrode 55, an insulating film may be formed on the diaphragm 50 side. Further, an ink supply port 49 for supplying ink to the common channel liquid chamber 48 is formed in the electrode substrate 42.

The bonding between the flow path substrate 41 and the electrode substrate 42 can be performed by an adhesive, but a more reliable physical bonding, for example, when the electrode substrate 42 is formed of silicon, A direct bonding method via an oxide film can be used. This direct bonding is performed at a high temperature of about 1000 ° C. When the electrode substrate 42 is made of glass, anodic bonding can be performed. When the electrode substrate 42 is formed of silicon and anodic bonding is performed, Pyrex glass may be formed between the electrode substrate 42 and the flow path substrate 41, and anodic bonding may be performed via this film. Furthermore, the flow path substrate 41 and the electrode substrate 42 can be bonded by eutectic bonding in which a binder such as gold is interposed between bonding surfaces using a silicon substrate.

The electrodes 55 of the electrode substrate 42 include:
A commonly used in the process of forming a semiconductor element
A high-rigidity member such as l, Cr, Ni, or the like, a high-melting-point metal such as Ti, TiN, or W, or a polycrystalline silicon material whose resistance is reduced by impurities can be used. Electrode substrate 42
Is formed of a silicon wafer, an insulating layer (the above-described oxide film layer 42a) is provided between the electrode substrate 42 and the electrode 55.
Need to be formed. When an insulating material such as a glass substrate or a ceramic substrate is used for the electrode substrate 42, the electrode 55 is used.
It is not necessary to form an insulating layer between the two.

When a silicon substrate is used as the electrode substrate 42, an impurity diffusion region can be used as the electrode 55. In this case, an impurity used for diffusion is an impurity having a conductivity type opposite to the conductivity type of the substrate silicon, a pn junction is formed around the diffusion region, and the electrode 55 and the electrode substrate 42 are formed.
Are electrically insulated from each other.

The nozzle plate 43 has a large number of nozzles 44 formed thereon. As will be described later, a resin member 71 and a high-rigidity member 72 are laminated and water repellent is applied to the surface of the resin member 71 (discharge surface side surface). The film 74 is formed. The nozzle plate 43 is bonded to the flow path substrate 41 with an adhesive.

Then, an FPC cable 61 in which a driver IC (driving IC chip) 60 as a head driving circuit is mounted by wire bonding on an electrode take-out portion 55a continuous with the electrode 55 of the ink jet head 40, and an anisotropic conductive film or the like is used. Connected through. At this time, the electrode substrate 4
The gap between the electrode extraction portion 55a and the nozzle plate 43, including the gap between the nozzle plate 2 and the nozzle plate 43 (the entrance of the gap 56), is hermetically sealed with a gap sealing agent 62 using an adhesive such as an epoxy resin. This prevents moisture from entering the gap 56 and preventing the diaphragm 50 from being displaced.

Further, the nozzle plate 43 of the ink jet head 40 is sealed and joined to the frame member 65 with a gap sealing agent 68, and the ink on the surface of the nozzle plate 43 having water repellency is applied to the electrode substrate 42, the FPC cable 61 and the like. Prevents sneaking around. The frame member 65 has an ink supply hole 66 for supplying ink from outside to the common liquid chamber flow path 48 of the inkjet head 40, and the FPC cable 61 and the like have holes 67 formed in the frame member 65. Is stored in.

The frame member 6 of the head 14
5 includes a joint member 70 with the ink cartridge 15.
Are connected to each other, and ink is supplied from the ink cartridge 15 to the common liquid chamber flow path 48 through the ink supply hole 66 through the filter 71 thermally fused to the frame member 65.

In the ink-jet head 40, the diaphragm 50 and the electrode 55 are connected to each other by applying a driving voltage between the diaphragm 50 and the electrode 55 by using the diaphragm 50 as a common electrode and the electrode 55 as an individual electrode. The diaphragm 50 is deformed and displaced toward the electrode 55 due to the electrostatic force generated during the period, and the electric charge between the diaphragm 50 and the electrode 55 is discharged from this state. By changing the internal volume (volume) / pressure of
Ink droplets are ejected from the nozzles 44.

That is, when a pulse voltage is applied to the electrode 55 serving as an individual electrode, a potential difference is generated between the electrode 55 and the diaphragm 50 serving as a common electrode, and an electrostatic force is generated between the individual electrode 55 and the diaphragm 50. As a result, the diaphragm 50 is displaced according to the magnitude of the applied voltage. After that, the applied pulse voltage falls, whereby the displacement of the diaphragm 50 is restored, and the restoring force increases the pressure in the pressurizing chamber 46, thereby ejecting ink droplets from the nozzles 44.

The details of the nozzle plate 43 of the ink jet head 40 will be described with reference to FIG. The nozzle plate 43 is formed by bonding an organic resin member 71 and a high rigidity member 72 to an adhesive 73 made of thermoplastic polyimide.
And a water-repellent film 74 is formed on the surface of the organic resin member 71 (surface on the discharge side) with a base layer 75 interposed therebetween. Nozzle communication port 76 communicating with nozzle 44 to member 72
Is formed. The nozzle plate 43 has the high rigidity member 72 side bonded to the flow path substrate 41 with an adhesive 77.

Here, as the organic resin member 71, an ink-resistant organic resin material such as thermosetting polyimide, polyether sulfone, or polyphenylene sulfide is selected. The thickness of the organic resin member 71 is 10 to
50 μm is sufficient.

As the high rigidity member 72, Ni / Co / Fe
Kovar, which is a low-expansion coefficient alloy having a thermal expansion coefficient of 3 to 4 × 10E ⁻⁶ / ° C., is used. The Kovar material is a silicon substrate forming the flow path substrate 41 (coefficient of thermal expansion of 2-3 × 1).
0E ^-6 / ° C) and the coefficient of linear thermal expansion is approximately the same.
Generation of distortion due to joining can be reduced. The thickness of the high rigidity member 72 is about 20 to 50 μm.

The high-rigidity member 72 can be etched using a fernico material, a stainless material (SUS304, 430) or the like. Furthermore, a ceramic material that can be made into a normal green sheet, BaTi
Using O ₃ , Mg / Al 2 O ₃ , zeolite, or the like, it can be processed by press molding, firing, or the like.

The organic resin member 71 and the high rigid member 7
2 can increase the rigidity of the entire nozzle plate 43. That is, the Young's modulus of the organic resin member 71 is about 100 to 300 kg / mm ² ,
0~15000Kg / mm ^2, of ceramics 10000
When compared to ２０20,000 kg / mm ² , the organic resin member 71 alone may be deformed following the driving pressure of the ink jet, resulting in a pressure loss and a drop in ink droplet velocity Vj. By bonding a high-rigidity member 72 such as a metal or ceramic under the resin member 71 with a thin film adhesive (adhesive layer) 73, the overall rigidity is improved.

The adhesive layer 73 is made of thermoplastic polyimide. Heat and pressure bonding using thermoplastic polyimide is performed at 150 to 300 ° C./0.1 to 8 kg /, depending on the material.
In cm ^2, it is possible to complete the bonding at 30 seconds,
Process tact can be shortened. Thermoplastic polyimide is a thermosetting polyimide whose main component is a skeleton-bonded thermoplastic material or a wholly aromatic polyimide, which is a highly alkali-resistant polyimide material, so that good ink durability can be obtained. .

The water-repellent film 74 is formed by converting a water-repellent agent into a mist and adhering and fixing it to the surface of the organic resin member 71. By forming the water-repellent agent into a mist, a water-repellent film having a uniform film thickness can be formed. After forming the nozzle 44 having a high-precision hole diameter on the organic resin member 71 with an excimer laser, By forming the water-repellent film 74, variation between the end of the hole (nozzle hole) serving as the nozzle 44 and the end of the water-repellent film 74 is reduced, and the nozzle 44 excellent in the ink droplet ejection direction can be obtained. it can.

As the base film (undercoat film) 75, a metal oxide film or a silane coupling material film is used. When a metal oxide film is formed as the base film 75, the silane coupling material and the silanol group contained in the water repellent material partially form ionic bonds with oxygen molecules of the metal oxide film to form a strong water repellent film 74. Adhesiveness is obtained. When a film of a silane coupling material (HMDS) is formed as the base film 75, the compatibility between the silane coupling material and the water repellent is improved by selecting a material having a similar wettability (SP value). Thus, strong adhesion of the water repellent film 74 is obtained.

Further, the surface of the organic resin member 71 is exposed to plasma discharge so that the water-repellent film 74 can be formed.
Strong adhesiveness can be obtained. In this case, the base film 7 described above is formed on the surface of the exposed organic resin member 71.
By forming the film 5 and further forming the water-repellent film 74 on the base film 75, it is possible to obtain stronger adhesion between the organic resin member 71 and the water-repellent film 74.

Therefore, the step of forming the water-repellent film 74 will be described with reference to FIG. Here, the organic resin member 71 is joined to the high rigid member 72 having the nozzle communication port 76 formed thereon through the adhesive layer 73, and then a hole to be the nozzle 44 is formed in the organic resin member 71 with high energy rays such as excimer laser. Then, a high-rigidity member 72 is bonded and bonded to the separately manufactured flow path substrate 41 (bonded to the electrode substrate 42) with an adhesive 77 to form an ink jet head, and then the surface of the organic resin member 71 (nozzle plate) 43 surface). The thickness of the water-repellent film 74 is 0.0
It is in the range of 01 to 5 μm.

The water-repellent film 74 is obtained by forming a thin film on the surface of the organic resin member 71 by converting a fluorinated water-repellent agent into a mist. That is, for example, as shown in FIG. 7, the completed heads H, H... On the other hand, a mist generating means 82 for generating a mist of the water repellent is disposed below the conveying means 81. This mist generating means 82 puts a water repellent 84 dissolved or dispersed in a solvent or an organic solvent of a fluorinated hydrocarbon in a container 83,
A water repellent 84 by an ultrasonic generator 85 attached to the container 83;
The water repellent 84 is turned into a mist by applying an ultrasonic wave to the container 83, and a water repellent mist 86 is generated from the opening 83 a of the container 83. When the organic resin member 71 of the head H conveyed by the conveyance means 81 in the atmosphere of the water repellent mist 86 passes for a predetermined time, the water repellent 8
The fine particles of No. 4 adhere to form a water-repellent film 74 which is a thin film of a water-repellent agent.

Here, the ultrasonic oscillating device 85 is an ordinary 2
From 8, 36, 48 KHz to 800 K to 1 MHz
Any of the Ultrasonic devices may be used, and the higher the oscillation frequency, the finer the particles. The thickness of the water-repellent film 74 to be formed depends on the durability of the water-repellent agent, but is 0.001 μm.
m, that is, an annealing film of about 10 ° has a water repellent effect. The formation of such a uniform thin film is achieved when the fine particles are 0.5
The mist may be formed so as to be not more than μm. When a highly durable water-repellent film having a thickness of about 5 μm or more is formed,
Although it is impossible to form a uniform film by a roll coater method, a spin coat method, or a squeegee method, uniform film formation can be performed at high speed by forming particles into a large mist of 1 to 5 μm. Become like

As described above, after forming the nozzle holes in the organic resin member of the head, a water-repellent agent is mist-adhered to the surface of the organic resin member and adhered and fixed to form a water-repellent thin film (water-repellent film). By this, a water-repellent film can be formed uniformly up to the end of the nozzle, and after forming a water-repellent film containing an ultraviolet absorbent or the like on the surface of the organic resin member as before, together with the opening of the nozzle hole with an excimer laser As compared with the case where the water-repellent film is opened, the mismatch between the nozzle end and the end of the water-repellent film is reduced, and the ink droplet ejection characteristics are improved.

Further, by controlling the particle size of the mist by controlling the driving frequency of the ultrasonic oscillator, the film thickness can be controlled and the film formation speed can be adjusted, and the desired thickness can be uniformed. A water-repellent film can be obtained.

Here, as shown in FIG. 9, fine particles of a solid phase fluororesin (such as PTEF) having a particle size of 0.
001 to 2 μm) 91, and a silane coupling material 92 is further added, and these solid fluorocarbon resin particles and the silane coupling material are also mixed and misted with a water repellent,
The water-repellent film 7 is adhered and fixed to the surface of the organic resin member 71.
4 can be formed by incorporating fine particles of a solid phase fluororesin or a silane coupling material.

In this case, a non-crystalline or crystalline water-repellent film 74 is formed by mixing and forming fine particles (particle diameter: 0.001 to 2 μm) of solid phase fluororesin such as PTEF. In addition, by forming the composite material, a water-repellent film 84 can be formed.
Can be controlled (0.001 to 5 μm), and the wear resistance is improved. Then, the adhesion of the amorphous body film is strengthened by annealing and the formation of the hard coat film, and the addition of a silane coupling material further increases the firmness of the crystalline fluororesin particles, which are usually difficult to fix. A film can be formed.

As described above, the water repellent is converted into a mist and fixed to the surface of the organic resin member 71, so that even a water repellent containing solid fine particles can be uniformly mist-formed and mixed with an amorphous material to form a film. By doing so, the abrasion resistance is increased by the solid particles, and resistance to wiping (part of the maintenance and recovery operation by the reliability maintenance and recovery mechanism) can be secured.

When the water repellent is converted into a mist to form a thin film that becomes a water repellent film, it is preferable to quickly separate and volatilize the solvent so as not to flow after the mist adheres. Can be formed. Therefore, although it depends on the heat of vaporization (latent heat) of the organic solvent, 40 ° C. to 2 ° C.
By jetting a heating gas of 00 ° C. (carrier gas N ₂ , air, and an organic gas having a large specific heat) from the nozzle holes of the ink jet head, the temperature of the ink jet head is controlled, the temperature is raised to a target temperature, and the ink is quickly dried. At a high temperature (150 ° C. or higher), film formation annealing proceeds simultaneously, and the thin film of the water repellent becomes a hard-coated water repellent film.

Specifically, for example, as shown in FIG.
When the inkjet head H is transported while being held by the head holder 101 to the transport unit 81, the heating gas is supplied from the heating gas source 102 such as N ₂ , air, or an organic gas having a large specific heat via the tube 103 to the ink of the head H. By feeding the gas into the supply hole 66, the heating gas is ejected from the nozzles 44, and the head H is heated by the heating gas,
When the mist-formed water repellent adheres to the surface of the organic resin member 71, the organic solvent is quickly separated and volatilized, and the fine particles of the water repellent adhere to the surface of the organic resin member 71 to form the water repellent film 74.

At this time, the gas source pressure gauge 104 of the gas source 101 is kept at a constant pressure,
If the pressure indicated by 5 is higher than normal, the nozzle 4
4 indicates that clogging has occurred, and when it is small, it can be seen that a leak has occurred in the head H (poor bonding or the like has occurred).

As described above, the formation of a uniform thin film by the mist method depends on how the solid component is not allowed to flow, the organic solvent is volatilized to form the film, and the flattening is performed by annealing. According to the method of feeding the heating gas into the inside, all the process factors can be controlled. By causing the mist to adhere while ejecting the heating gas from the nozzle hole, the water repellent is prevented from flowing into the nozzle hole, and the film can be easily annealed, thereby shortening the process.

A similar effect can be obtained by attaching and transporting the completed inkjet head H to, for example, the transporting means 81 while being heated to, for example, 80 ° C. or higher, and attaching a mist-forming water repellent. In this case, if the head H is heated to 150 ° C. or higher, the steps including the film annealing can be performed as described above. Also, by heating the entire head, the entire head can be coated with a water-repellent agent, thereby preventing the entire head from dust and preventing dust and ink from adhering.

If the organic resin substrate is coated directly with the water repellent, the adhesion may not be sufficient. Therefore, as described above, the organic resin member 71
A water repellent film 74 is formed on the surface of the substrate with a base layer 75 interposed therebetween.

As the underlayer 75, for example, a metal oxide film 111 can be used as shown in FIG. As the metal oxide film 111, for example, TiO _2-x , Ni
O, In2O3, Cr2O3- _x , etc. can be mentioned. Such a metal oxide film 111 is directly formed on the surface of the organic resin member 71 as a base film of about 100 to 1000 °, and a water repellent is coated on the surface of the metal oxide film 101 to form a water repellent film 74.

In this case, the silane coupling material and the silanol group contained in the water repellent material form a partial ionic bond with oxygen molecules of the metal oxide film 101. Specifically, cause binding of the metal oxide _{M-O-Si-CnF 2} n-CF 3 ( water-repellent film), dehydrated reaction _{(H 2 O, O (CH} 3) 2 is removed), thereby Strong adhesion of the water-repellent film 74 is obtained.

As the underlayer 75, for example, FIG.
As shown in the figure, a film 1 of a silane coupling material (HMDS)
12 can be used. In this case, for example, an organic solvent
Roll coating of dilute silane coupling material
Utilizing the high air pressure, the head is turned into mist and
Pass through or hold in a vapor pressure atmosphere.
And about 50-1000mm (0.001-1μm) thick
Each time, as a base film 75, silane
A film 112 of a coupling material is formed (dehydration reaction H ₂O removal
O-Si-CnH₂n-CH₃Joins
You. ), And water repellent with the head mist as described above
By passing through the atmosphere of the agent mist, the silane coupling
The water-repellent film 74 is formed on the surface of the film 112 of the coating material.

In this case, by selecting a material whose wettability (SP value) between the silane coupling material and the water repellent is close to each other, the compatibility is improved, and the film 112 of the silane coupling material and the water repellent film 74 are improved. And the adhesion to the film is improved. That is, the organic resin member 71 and the thin film 112 of the first layer silane coupling material
Adheres with water-repellent or higher adhesion with wettability (SP value)
Strong adhesion due to a synergistic effect with hydrolysis of some silanol groups. Furthermore, the water-repellent film 74 of the second layer adheres firmly by interaction with the silane coupling agent or silanol group contained therein. The bonding species at this time is a CO—Si—R + water-repellent film.

Next, a case in which a polyimide substrate is used as the organic resin member 71 will be described. When the polyimide substrate is directly bonded or bonded to another surface due to the stability of the material, a strong adhesion is obtained. It is difficult. Therefore, in particular, when a polyimide substrate is used, it is preferable to perform the surface treatment of the exposure plasma by passing the polyimide substrate between electrodes of atmospheric pressure plasma.

More specifically, as shown in FIG.
21 and 122 (disposed at an interval of about 20 mm)
When a voltage of 1 K to 5 Kv is applied from the power supply 123 at a frequency of 2 K to 100 KHz from the power supply 123, atmospheric discharge occurs depending on the impedance between the electrodes. Between the discharge plasmas, an inkjet head H using a polyimide substrate as the organic resin member 71 is passed by a transport means 81 such as a transport belt formed of a nonconductive material such as polyimide, silicone, or glass wool. At this time, the electrode 12
A small amount of gas for initiating discharge and maintaining discharge is introduced between 1 and 122.

By performing the exposure treatment to the plasma discharge on the surface of the organic resin member 71 in this manner, as shown in FIG. 13, the exposed surface 71a of the organic resin member 71 is exposed.
, A functional group such as a carboxylic acid group, a ketone group, or a hydroxyl group is generated by activated oxygen ions, air gas radicals, or the like. These functional groups can directly react and bond with the water repellent, and even when the undercoat film 75 is formed as described above, a strong adhesive bond accompanied by a dehydration reaction with the silane coupling material is possible, Further, since a strong bonding film can be secured because a reaction with an oxide film is involved even in the formation of a thin film of a metal oxide, a base film 75 is formed on the surface 71a of the exposed organic resin member 71 as shown in FIG. A water-repellent film 74 can be formed on the base film 75.

Here, an example in which such surface treatment (plasma exposure), formation of an underlayer, and formation of a water-repellent film are performed in a series of steps will be described with reference to FIG. As shown in the figure, the transport means 115 transports the head H using the polyimide substrate as the organic resin member 71. Then, in the stage S1, the head H is passed between the electrodes 121 and 122 to perform the plasma exposure processing on the surface of the organic resin member 71 as described above.

Next, a mist generating means 131 for the silane coupling material is arranged on the stage S2. The mist generating means 131 puts the silane coupling material 133 in the container 132 and applies ultrasonic waves by the ultrasonic generator 134 to mist the silane coupling material 133.
Then, the film 112 of the silane coupling material is formed on the surface of the organic resin member 71 by passing the head H through the atmosphere of the mist 135 of the silane coupling material. Then, the head H is heated by a heating means 137 such as a lamp to separate and volatilize the organic solvent to form the base film 75.

Thereafter, in the stage S3, a thin film of the water-repellent is formed by passing through the atmosphere of the water-repellent mist 86 generated by the water-repellent mist generating means 83 described above. Next, the thin film is hard-coated by the hard-coating means 138 for irradiating ultraviolet rays or infrared rays to form the water-repellent film 74, whereby the inkjet head 4 is formed.
Complete 0.

In the above embodiment, the present invention is applied to the nozzle forming member of the electrostatic ink jet head. However, the present invention can be applied to a nozzle forming member other than the ink jet head. The present invention can be applied to a nozzle forming member such as an ink jet head or a bubble type ink jet head, and can be applied not only to a serial type ink jet recording apparatus but also to a line type ink jet recording apparatus. Further, as the droplet discharge head, other than an ink jet head, a head for discharging a liquid resist can be used.

[0079]

As described above, according to the nozzle forming member of the present invention, the water-repellent film is formed by adhering the mist-formed water-repellent to the surface of the resin member. The variation between the portion and the end portion of the water-repellent film is reduced, the droplet discharge direction is stabilized, and the droplet discharge characteristics are improved.

According to the nozzle forming member of the present invention, since the water-repellent film is formed on the surface of the resin member via the base film, the adhesion between the resin member and the water-repellent film is improved, and the water-repellent film without peeling is formed. A film is obtained. Here, since the base film is a metal oxide film or a film of a run coupling material, strong adhesion without peeling can be performed.

According to the nozzle forming member of the present invention, the water-repellent film is formed on the surface of the resin member which has been subjected to the exposure treatment between the plasma discharges. And the adhesiveness with the resin is improved.

In each of the nozzle forming members according to the present invention, the resin member and the high-rigidity member are joined by an adhesive made of a thermoplastic polyimide, so that the members having excellent liquid resistance and different expansion coefficients are buffered. And the heat resistance is improved. In addition, by using Kovar, Fernico, SUS material, or copper material as the high rigidity member, a nozzle plate excellent in other rigidity can be obtained. Further, when the resin member is made of polyimide, the nozzle diameter accuracy can be improved.

The wear resistance is improved by including solid-phase fluororesin fine particles in the water-repellent film. Further, by including a silane coupling material in the water-repellent film, crystalline fluororesin particles can also be fixed, and a strong water-repellent film can be obtained.

According to the nozzle forming member according to the present invention, since the resin member and the high-rigidity member are joined by the adhesive made of thermoplastic polyimide, they are excellent in liquid resistance and buffer-joined members having different expansion rates. And the heat resistance is improved.

According to the droplet discharge head according to the present invention, since the nozzle forming member formed with the nozzle is any one of the nozzle forming members according to the present invention, the droplet discharge characteristics are improved and the image quality is improved.

According to the method of manufacturing a droplet discharge head according to the present invention, the water repellent is formed into a mist and adhered to the surface of the resin member to form a water repellent film. A water-repellent film can be formed in a stable manner, the droplet ejection direction is stable,
Drop ejection characteristics are improved.

Here, when a thin film is formed, a heated gas is introduced from the ink inlet of the head and ejected from the nozzle, whereby the water-repellent film can be prevented from entering the inside of the nozzle, and variation in meniscus vibration can be prevented. As a result, the water-repellent film can be annealed and fixed at the same time by heating at 120 ° C. or higher. Also, by forming a water-repellent film by attaching the water-repellent agent to the surface of the nozzle forming member of the heated head which is mist-formed, it is possible to simultaneously perform annealing and fixation of the water-repellent film and to the entire head. Can be formed.

Further, before forming the water-repellent film, a metal oxide film or a silane coupling material film is formed on the surface of the resin member of the head, so that the organic resin member is bonded to the water-repellent film. Power improves. Alternatively, the adhesive strength between the organic resin member and the water-repellent film is also improved by subjecting the surface of the resin member of the head to exposure to plasma discharge before forming the water-repellent film.

[Brief description of the drawings]

FIG. 1 is a schematic perspective explanatory view of a mechanism of an ink jet recording apparatus provided with an ink jet head which is a droplet discharge head according to the present invention.

FIG. 2 is an explanatory side view of the mechanism.

FIG. 3 is an exploded perspective view of an inkjet head of the recording apparatus.

FIG. 4 is a schematic cross-sectional explanatory view of the head along the longitudinal direction of the diaphragm.

FIG. 5 is an enlarged explanatory view of a main part of the head along a diaphragm longitudinal direction.

FIG. 6 is a schematic cross-sectional explanatory view of the head along the transverse direction of the diaphragm.

FIG. 7 is an enlarged sectional explanatory view of a nozzle plate of the head.

FIG. 8 is an explanatory view illustrating a method of forming a water-repellent film in the method of manufacturing the head.

FIG. 9 is an explanatory view illustrating another example of the method for forming the water-repellent film.

FIG. 10 is an explanatory view for explaining a head heating method in the method of manufacturing the head.

FIG. 11 is an explanatory view illustrating a step of forming a base film and a water-repellent film in the method of manufacturing the head.

FIG. 12 is an explanatory diagram for explaining another forming process of the base film and the water-repellent film in the method of manufacturing the head.

FIG. 13 is an explanatory view for explaining an exposure treatment method for plasma discharge in the method of manufacturing the head.

FIG. 14 is an explanatory view of a nozzle plate subjected to the exposure processing.

FIG. 15 is an explanatory view illustrating a series of manufacturing steps of a head including the nozzle plate of FIG. 14;

[Explanation of symbols]

13: carriage, 14: head, 24: transport roller,
33: paper discharge roller, 41: flow path substrate, 42: electrode substrate,
43 ... nozzle plate, 44 ... nozzle, 46 ... pressurizing chamber, 47 ...
Fluid resistance part, 48: common liquid chamber flow path, 50: diaphragm, 55
... Electrode, 56 ... Gap, 71 ... Organic resin member, 72 ...
High rigidity member, 73: adhesive layer, 74: water repellent film, 75: base film, 84: water repellent, 86: mist of water repellent.

Claims (16)

[Claims] In a nozzle forming member in which a resin member having a nozzle for discharging liquid droplets and a high-rigidity member are laminated, and the water-repellent film is formed on the surface of the resin member, the water-repellent film is mist-formed. A nozzle forming member, wherein a water repellent is attached to the surface of the resin member. 2. A nozzle forming member in which a resin member having a nozzle for discharging droplets and a high-rigidity member are laminated and a water-repellent film is formed on the surface of the resin member, wherein a base film is formed on the surface of the resin member. A nozzle forming member, wherein the water-repellent film is formed through the nozzle forming member. 3. The nozzle forming member according to claim 2, wherein the base film is a metal oxide film or a film of a silane coupling material. 4. In a nozzle forming member in which a resin member having a nozzle for discharging droplets and a high rigidity member are laminated and a water-repellent film is formed on a surface of the resin member, the water-repellent film is placed between plasma discharges. A nozzle forming member formed on the surface of the resin member that has been subjected to the exposing process. 5. The nozzle forming member according to claim 1, wherein the resin member and the high-rigidity member are joined by an adhesive made of a thermoplastic polyimide. . 6. The nozzle forming member according to claim 1, wherein the high-rigidity member is any one of Kovar, Fernico, SUS material, and copper material. 7. The nozzle forming member according to claim 1, wherein said resin member is polyimide. 8. The droplet discharge head according to claim 1, wherein the water-repellent film contains solid-phase fluororesin fine particles. 9. The droplet discharge head according to claim 1, wherein the water-repellent film contains a silane coupling material. 10. A nozzle forming member comprising a laminated member of a resin member having a nozzle for discharging liquid droplets and a high-rigidity member, wherein said resin member and said high-rigidity member are joined by an adhesive made of thermoplastic polyimide. A nozzle forming member. 11. A droplet discharge head comprising: a nozzle for discharging droplets; a pressurized chamber communicating with the nozzle; and energy generating means for generating energy for pressurizing ink in the pressurized chamber. 11. A droplet discharge head, wherein a nozzle forming member having a nozzle formed thereon is the nozzle forming member according to any one of claims 1 to 10. 12. In a method for manufacturing a droplet discharge head including a nozzle forming member in which a resin member and a high-rigidity member are laminated and a water-repellent film is formed on the surface of the resin member, the water-repellent is converted into mist. A method for manufacturing a droplet discharge head, wherein the water-repellent film is formed by being attached to a surface of the resin member. 13. The method of manufacturing a droplet discharge head according to claim 12, wherein a heated gas is introduced from an ink injection port of the head and ejected from the nozzle when forming the thin film. A method for manufacturing a droplet discharge head. 14. The method of manufacturing a droplet discharge head according to claim 12, wherein the water-repellent agent is mist-formed and adhered to the surface of the nozzle forming member of the heated head to form the water-repellent film. A method for manufacturing a droplet discharge head, which is characterized in that: 15. The method for manufacturing a droplet discharge head according to claim 12, wherein a metal oxide film or silane is formed on a surface of a resin member of the head before forming the water-repellent film. A method for manufacturing a droplet discharge head, comprising forming a film of a coupling material. 16. The method for manufacturing a droplet discharge head according to claim 12, wherein a surface of a resin member of the head is exposed to plasma discharge before forming the water-repellent film. A method for manufacturing a droplet discharge head.