JP4450256B2 - Droplet discharge head and droplet discharge apparatus - Google Patents

Description

  The present invention relates to a droplet discharge head and a droplet discharge device.

For example, a droplet discharge device such as an ink jet printer is provided with a droplet discharge head for discharging droplets. As such a droplet discharge head, for example, an ink chamber (cavity) that communicates with a nozzle that discharges ink as droplets and stores ink, and a piezoelectric element for driving that deforms the wall surface of the ink chamber are provided. What you have is known.
In such a droplet discharge head, a part of the ink chamber (vibrating plate) is displaced by expanding and contracting the driving piezoelectric element. Thereby, the volume of the ink chamber is changed and ink droplets are ejected from the nozzles.

By the way, such a droplet discharge head is assembled by bonding a nozzle plate in which nozzles are formed and a substrate that defines an ink chamber with a photosensitive adhesive or an elastic adhesive ( For example, see Patent Document 1).
However, when supplying the adhesive between the nozzle plate and the substrate, it is extremely difficult to strictly control the supply amount of the adhesive. For this reason, the amount of the adhesive to be supplied cannot be made uniform, and the distance between the nozzle plate and the substrate becomes non-uniform. As a result, the volumes of the plurality of ink chambers provided in the droplet discharge heads become non-uniform, or the volumes of the ink chambers become non-uniform for each droplet discharge head. Further, the distance between the droplet discharge head and the print medium such as print paper becomes non-uniform. Furthermore, there is a possibility that the adhesive protrudes from the joint location. Due to such a problem, the dimensional accuracy of the droplet discharge head is lowered, and the printing quality of the ink jet printer is lowered.
Further, the adhesive is exposed to ink stored in the ink chamber for a long time. When the adhesive is exposed to the ink in this manner, the adhesive is altered or deteriorated by the organic component in the ink. For this reason, there is a possibility that the liquid tightness of the ink chamber may be lowered, or components in the adhesive may be eluted into the ink.

On the other hand, there is also known a method of joining the respective parts constituting the droplet discharge head by a solid joining method.
Solid bonding is a method in which members are directly bonded without interposing an adhesive layer such as an adhesive. For example, methods such as a silicon direct bonding method and an anodic bonding method are known.
However, for solid bonding,
・ Materials of members that can be joined are limited. ・ The joining process involves heat treatment at a high temperature (for example, about 700 to 800.degree. C.). ・ The atmosphere in the joining process is limited to a reduced pressure atmosphere. There is a problem that can not be done.

Japanese Patent Laid-Open No. 5-155017

  An object of the present invention is to provide a highly reliable droplet discharge head that is excellent in dimensional accuracy and chemical resistance, and capable of high-quality printing over a long period of time, and a highly reliable droplet having such a droplet discharge head It is to provide a discharge device.

Such an object is achieved by the present invention described below.
Droplet discharge head of the present invention includes a base plate,
Provided on one surface of the pre-Symbol substrate, a nozzle plate having nozzle holes for ejecting ejection exudates as droplets,
Anda sealing plate provided on the other surface of the front Stories substrate,
A discharge liquid storage chamber for storing the discharge liquid is formed by the substrate, the nozzle plate, and the sealing plate,
The substrate and the nozzle plate are bonded via a bonding film,
The bonding film has been more formed in the plasma Polymerization includes an Si skeleton which have a siloxane (Si-O) bond, and the leaving group bonded to the Si skeleton, the Si-H bonds,
By the application of energy to the bonding film, wherein the leaving groups present on the front surface of the bonding film is desorbed from the Si skeleton, the adhesion was expressed in the table surface of the bonding film, the bonding film, The substrate and the nozzle plate are joined.
As a result, a highly reliable droplet discharge head that has excellent dimensional accuracy and chemical resistance and can perform high-quality printing over a long period of time can be obtained. Further, the bonding film formed by the plasma polymerization method becomes dense and homogeneous. And a board | substrate and a nozzle plate can be joined especially firmly. Furthermore, the bonding film manufactured by the plasma polymerization method is maintained in an activated state by applying energy for a relatively long time. For this reason, it is possible to simplify and improve the efficiency of the manufacturing process of the droplet discharge head.
Further, it is considered that the Si—H bond inhibits the generation of siloxane bond regularly. For this reason, the siloxane bond is formed so as to avoid the Si—H bond, and the regularity of the Si skeleton is lowered. In this manner, the Si skeleton having a low degree of crystallinity can be efficiently formed by including Si—H bonds in the bonding film.

In the liquid droplet ejection head according to the present invention, the total of the Si atom content and the O atom content is 10 to 90 atomic% among atoms obtained by removing H atoms from all atoms constituting the bonding film. Is preferred.
Thus, in the bonding film, Si atoms and O atoms form a strong network, and the bonding film itself becomes stronger. For this reason, the bonding film exhibits particularly high bonding strength with respect to the substrate and the nozzle plate.

In the liquid droplet ejection head of the present invention, the abundance ratio of Si atoms and O atoms in the bonding film is preferably 3: 7 to 7: 3.
Thereby, the stability of the bonding film is increased, and the substrate and the nozzle plate can be bonded more firmly.
In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the Si skeleton includes a siloxane bond and has a random atomic arrangement.
In the droplet discharge head of the present invention, the crystallinity of the Si skeleton is preferably 45% or less.
As a result, the Si skeleton includes a sufficiently random atomic structure. For this reason, the characteristics of the Si skeleton become obvious, and the dimensional accuracy and adhesiveness of the bonding film become more excellent.

In the droplet discharge head of the present invention, when the peak intensity attributed to the siloxane bond is 1, the peak intensity attributed to the Si—H bond is 1 in the infrared absorption spectrum of the bonding film including the Si—H bond. It is preferable that it is 0.001-0.2.
As a result, the atomic structure in the bonding film becomes relatively random. For this reason, the bonding film is particularly excellent in bonding strength, chemical resistance and dimensional accuracy.

In the droplet discharge head of the present invention, the leaving group is an H atom, a B atom, a C atom, an N atom, an O atom, a P atom, an S atom, and a halogen atom, or each of these atoms in the Si skeleton. It is preferably composed of at least one selected from the group consisting of atomic groups arranged to be bonded.
These leaving groups are relatively excellent in binding / leaving selectivity by applying energy. For this reason, such a leaving group can make the adhesiveness of the bonding film higher.

In the droplet discharge head of the present invention, the leaving group is preferably an alkyl group.
Since the alkyl group has high chemical stability, the bonding film containing the alkyl group as a leaving group is excellent in weather resistance and chemical resistance.
In the droplet discharge head of the present invention, when the peak intensity attributed to the siloxane bond is 1 in the infrared absorption spectrum of the bonding film containing a methyl group as the leaving group, the peak intensity attributed to the methyl group is It is preferable that it is 0.05-0.45.
As a result, the content ratio of the methyl group is optimized, and a necessary and sufficient number of active hands are generated in the bonding film while preventing the methyl group from unnecessarily inhibiting the formation of the siloxane bond. Adhesiveness is sufficient. Further, the bonding film exhibits sufficient weather resistance and chemical resistance due to the methyl group.

In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the bonding film is made of polyorganosiloxane as a main material.
As a result, the bonding film itself has excellent mechanical properties. In addition, a bonding film exhibiting particularly excellent adhesion to many materials can be obtained. Therefore, the substrate and the nozzle plate can be more firmly bonded by this bonding film. Further, the bonding film can easily and reliably control the non-adhesiveness and the adhesiveness. Furthermore, since the bonding film exhibits excellent liquid repellency, a highly reliable head with excellent durability can be obtained.

In the droplet discharge head of the present invention, it is preferable that the polyorganosiloxane is mainly composed of a polymer of octamethyltrisiloxane.
Thereby, a bonding film having particularly excellent adhesiveness can be obtained.
In the droplet discharge head of the present invention, in the plasma polymerization method, it is preferable that a high frequency output density when generating plasma is 0.01 to 100 W / cm ² .
Accordingly, it is possible to reliably form a Si skeleton having a random atomic structure while preventing the plasma gas from being added to the source gas more than necessary due to the high frequency power density.
In the liquid droplet ejection head according to the aspect of the invention, it is preferable that an average thickness of the bonding film is 1 to 1000 nm.
Thereby, these can be joined more firmly, preventing that the dimensional accuracy between a board | substrate and a nozzle plate falls remarkably.

In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the bonding film is a solid having no fluidity.
As a result, a head having a remarkably high dimensional accuracy as compared with the prior art can be obtained. Further, since the time required for curing the adhesive is not required, strong bonding can be achieved in a short time.
In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the substrate is composed mainly of a silicon material or stainless steel.
Since these materials are excellent in chemical resistance, even if they are exposed to the discharge liquid for a long time, it is possible to reliably prevent the substrate or nozzle plate from being altered or deteriorated. Moreover, since these materials are excellent in workability, a substrate with high dimensional accuracy can be obtained. For this reason, the accuracy of the volume of the discharge liquid storage chamber is increased, and a droplet discharge head capable of high-quality printing is obtained.

In the droplet discharge head of the present invention, it is preferable that the nozzle plate is composed mainly of a silicon material or stainless steel.
Since these materials are excellent in chemical resistance, it is possible to reliably prevent the nozzle plate from being altered or deteriorated even when exposed to the discharge liquid for a long time. Moreover, since these materials are excellent in workability, a nozzle plate with high dimensional accuracy can be obtained.

In the liquid droplet ejection head according to the aspect of the invention, it is preferable that a surface of the substrate that is in contact with the bonding film is previously subjected to a surface treatment that improves adhesion with the bonding film.
Thereby, the bonding strength between the substrate and the bonding film can be further increased, and as a result, the bonding strength between the substrate and the nozzle plate can be increased.
In the droplet discharge head of the present invention, it is preferable that the surface of the nozzle plate that is in contact with the bonding film is previously subjected to a surface treatment that improves adhesion to the bonding film.
As a result, the bonding strength between the nozzle plate and the bonding film can be further increased, and as a result, the bonding strength between the substrate and the nozzle plate can be increased.

In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the surface treatment is a plasma treatment.
Thereby, in order to form the bonding film, the surface of the substrate or the nozzle plate can be particularly optimized.
In the droplet discharge head of the present invention, it is preferable that an intermediate layer is provided between the substrate and the bonding film.
Thereby, the bonding strength between the substrate and the bonding film can be increased, and a highly reliable droplet discharge head can be obtained.

In the liquid droplet ejection head of the present invention, it is preferable that an intermediate layer is provided between the nozzle plate and the bonding film.
As a result, the bonding strength between the nozzle plate and the bonding film can be increased, and a highly reliable droplet discharge head can be obtained.
In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the intermediate layer is composed mainly of an oxide-based material.
As a result, the bonding strength can be increased between the substrate and the bonding film and between the nozzle plate and the bonding film.

In the liquid droplet ejection head according to the aspect of the invention, the energy may be applied by at least one of a method of irradiating the bonding film with energy rays, a method of heating the bonding film, and a method of applying a compressive force to the bonding film. It is preferably carried out by one method.
Thereby, energy can be imparted to the bonding film relatively easily and efficiently.

In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the energy ray is an ultraviolet ray having a wavelength of 150 to 300 nm.
As a result, the amount of energy applied is optimized, and the bond between the Si skeleton and the leaving group is selectively cut while preventing the Si skeleton in the bonding film from being destroyed more than necessary. can do. Thereby, adhesiveness can be expressed in the bonding film while preventing the characteristics (mechanical characteristics, chemical characteristics, etc.) of the bonding film from deteriorating.

In the droplet discharge head of the present invention, the heating temperature is preferably 25 to 100 ° C.
Thereby, it is possible to reliably activate the bonding film while reliably preventing the substrate, the nozzle plate, or the like from being altered or deteriorated by heat.
In the droplet discharge head of the present invention, the compressive force is preferably 0.2 to 10 MPa.
As a result, sufficient adhesiveness can be exhibited in the bonding film by simply compressing the substrate or nozzle plate while avoiding damage or the like.

In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the substrate and the sealing plate are bonded via a bonding film similar to the bonding film.
Thereby, the adhesiveness of a board | substrate and a sealing plate becomes high, and can improve especially the liquid-tightness of a discharge liquid storage chamber.
In the liquid droplet ejection head of the present invention, the sealing plate is composed of a laminate formed by laminating a plurality of layers,
Of the layers in the laminate, it is preferable that at least one pair of adjacent layers is bonded via a bonding film similar to the bonding film.
Thereby, the adhesiveness between layers and the propagation property of strain are enhanced. For this reason, the distortion by the vibration means can be reliably converted into a pressure change in the discharge liquid storage chamber. That is, the response of the displacement of the sealing plate can be enhanced.

In the liquid droplet ejection head of the present invention, the liquid droplet ejection head is further provided on the opposite side of the sealing plate from the substrate, and has vibration means for vibrating the sealing plate,
It is preferable that the sealing plate and the vibration unit are bonded via a bonding film similar to the bonding film.
Thereby, the adhesiveness between the sealing plate and the vibration means and the distortion propagation property are enhanced. As a result, the distortion caused by the vibration means can be reliably converted into a pressure change in the discharge liquid storage chamber.

In the liquid droplet ejection head according to the aspect of the invention, it is preferable that the vibration unit includes a piezoelectric element.
Thereby, the degree of bending generated in the sealing plate can be easily controlled. Thereby, the size of the ink droplets can be easily controlled.
In the droplet discharge head of the present invention, the droplet discharge head further includes a case head provided on the opposite side of the sealing plate from the substrate,
It is preferable that the sealing plate and the case head are bonded via a bonding film similar to the bonding film.
Thereby, the adhesiveness of a sealing board and a case head becomes high. As a result, the case head can reliably support the sealing plate and reliably prevent the sealing plate, the substrate and the nozzle plate from being twisted or warped.
The liquid droplet ejection apparatus of the present invention includes the liquid droplet ejection head of the present invention.
Thereby, a highly reliable droplet discharge device can be obtained.

Hereinafter, a droplet discharge head and a droplet discharge apparatus of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<Inkjet recording head>
<< First Embodiment >>
First, a first embodiment in which the droplet discharge head of the present invention is applied to an ink jet recording head will be described.

  FIG. 1 is an exploded perspective view showing a first embodiment when the droplet discharge head of the present invention is applied to an ink jet recording head, FIG. 2 is a sectional view of the ink jet recording head shown in FIG. 1, and FIG. FIG. 2 is a schematic view showing an embodiment of an ink jet printer including the ink jet recording head shown in FIG. 1. In the following description, the upper side in FIGS. 1 and 2 is referred to as “upper” and the lower side is referred to as “lower”.

An ink jet recording head 1 (hereinafter, simply referred to as “head 1”) shown in FIG. 1 is mounted on an ink jet printer (droplet discharge device of the present invention) 9 as shown in FIG.
The ink jet printer 9 shown in FIG. 3 includes an apparatus main body 92, a tray 921 in which the recording paper P is installed at the upper rear, a paper discharge port 922 for discharging the recording paper P in the lower front, and an operation panel on the upper surface. 97.

The operation panel 97 includes, for example, a liquid crystal display, an organic EL display, an LED lamp, and the like, and a display unit (not shown) for displaying an error message and the like, and an operation unit (not shown) configured with various switches. And.
Further, inside the apparatus main body 92, mainly a printing apparatus (printing means) 94 provided with a reciprocating head unit 93 and a paper feeding apparatus (paper feeding means) for feeding recording paper P to the printing apparatus 94 one by one. 95 and a control unit (control means) 96 for controlling the printing device 94 and the paper feeding device 95.

  Under the control of the control unit 96, the paper feeding device 95 intermittently feeds the recording paper P one by one. The recording paper P passes near the lower part of the head unit 93. At this time, the head unit 93 reciprocates in a direction substantially orthogonal to the feeding direction of the recording paper P, and printing on the recording paper P is performed. That is, the reciprocating motion of the head unit 93 and the intermittent feeding of the recording paper P are the main scanning and sub-scanning in printing, and ink jet printing is performed.

The printing apparatus 94 includes a head unit 93, a carriage motor 941 that is a drive source of the head unit 93, and a reciprocating mechanism 942 that reciprocates the head unit 93 in response to the rotation of the carriage motor 941.
The head unit 93 includes a head 1 having a large number of nozzle holes 11, an ink cartridge 931 that supplies ink to the head 1, and a carriage 932 on which the head 1 and the ink cartridge 931 are mounted at the lower part thereof.

Ink cartridge 931 is filled with four color inks of yellow, cyan, magenta, and black (black), thereby enabling full color printing.
The reciprocating mechanism 942 includes a carriage guide shaft 943 whose both ends are supported by a frame (not shown), and a timing belt 944 extending in parallel with the carriage guide shaft 943.

The carriage 932 is supported by the carriage guide shaft 943 so as to be able to reciprocate and is fixed to a part of the timing belt 944.
When the timing belt 944 travels forward and backward via a pulley by the operation of the carriage motor 941, the head unit 93 reciprocates as guided by the carriage guide shaft 943. During this reciprocation, ink is appropriately discharged from the head 1 and printing on the recording paper P is performed.

The sheet feeding device 95 includes a sheet feeding motor 951 serving as a driving source thereof, and a sheet feeding roller 952 that is rotated by the operation of the sheet feeding motor 951.
The paper feed roller 952 includes a driven roller 952a and a drive roller 952b that are vertically opposed to each other with a feeding path (recording paper P) of the recording paper P interposed therebetween. As a result, the paper feed roller 952 can feed a large number of recording sheets P set on the tray 921 one by one toward the printing apparatus 94. Instead of the tray 921, a configuration in which a paper feed cassette that stores the recording paper P can be detachably mounted may be employed.

The control unit 96 performs printing by controlling the printing device 94, the paper feeding device 95, and the like based on print data input from a host computer such as a personal computer or a digital camera.
Although not shown, the control unit 96 mainly includes a memory that stores a control program for controlling each unit, a drive circuit that drives the printing device 94 (carriage motor 941), and a paper feeding device 95 (paper feeding motor 951). Drive circuit, a communication circuit for obtaining print data from a host computer, and a CPU that is electrically connected to these and performs various controls in each unit.

Further, for example, various sensors that can detect the remaining ink amount of the ink cartridge 931, the position of the head unit 93, and the like are electrically connected to the CPU.
The control unit 96 obtains print data via the communication circuit and stores it in the memory. The CPU processes the print data and outputs a drive signal to each drive circuit based on the process data and input data from various sensors. The printing device 94 and the paper feeding device 95 are operated by this drive signal. As a result, printing is performed on the recording paper P.

Hereinafter, the head 1 will be described in detail with reference to FIGS. 1 and 2.
As shown in FIGS. 1 and 2, the head 1 includes a nozzle plate 10, a discharge liquid storage chamber forming substrate (substrate) 20, a sealing sheet 30, and a vibration plate 40 provided on the sealing sheet 30. And a piezoelectric element (vibrating means) 50 and a case head 60 provided on the vibration plate 40. Moreover, in this embodiment, the sealing plate is comprised by the laminated body of the sealing sheet 30 and the diaphragm 40. FIG. The head 1 constitutes a piezo jet head.

A discharge liquid storage chamber forming substrate 20 (hereinafter referred to as “substrate 20”) is communicated with a plurality of discharge liquid storage chambers (pressure chambers) 21 for storing ink and each discharge liquid storage chamber 21. A discharge liquid supply chamber 22 for supplying ink to each discharge liquid storage chamber 21 is formed.
As shown in FIGS. 1 and 2, each of the discharge liquid storage chambers 21 and the discharge liquid supply chambers 22 has a substantially rectangular shape in plan view, and the width (short side) of each of the discharge liquid storage chambers 21 is The discharge liquid supply chamber 22 is narrower than the width (short side).

In addition, each discharge liquid storage chamber 21 is arranged so as to be substantially perpendicular to the discharge liquid supply chamber 22, and each discharge liquid storage chamber 21 and the discharge liquid supply chamber 22 are as a whole in plan view. It has a comb shape.
In addition, the discharge liquid supply chamber 22 may have a trapezoidal shape, a triangular shape, or a bowl shape (capsule shape) in addition to a rectangular shape as in the present embodiment in a plan view.

  Examples of the material constituting the substrate 20 include silicon materials such as single crystal silicon, polycrystalline silicon, and amorphous silicon, metal materials such as stainless steel, titanium, and aluminum, quartz glass, silicate glass (quartz glass), Glass materials such as alkali silicate glass, soda lime glass, potash lime glass, lead (alkali) glass, barium glass, borosilicate glass, alumina, zirconia, ferrite, silicon nitride, aluminum nitride, boron nitride, titanium nitride, carbonized Ceramic materials such as silicon, boron carbide, titanium carbide, tungsten carbide, carbon materials such as graphite, polyolefins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), cyclic polyolefin , Modified polyolefin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, polyimide, polyamideimide, polycarbonate, poly- (4-methylpentene-1), ionomer, acrylic resin, polymethyl methacrylate, acrylonitrile-butadiene-styrene Polymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrene copolymer, polyoxymethylene, polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH), polyethylene terephthalate (PET) ), Polyethylene naphthalate, polybutylene terephthalate (PBT), polycyclohexane terephthalate (PCT) and other polyesters, polyethers, polyether ketones (PEK) , Polyether ether ketone (PEEK), polyether imide, polyacetal (POM), polyphenylene oxide, modified polyphenylene oxide, modified polyphenylene ether resin (PBO), polysulfone, polyether sulfone, polyphenylene sulfide (PPS), polyarylate, fragrance Group polyester (liquid crystal polymer), polytetrafluoroethylene, polyvinylidene fluoride, other fluorine resins, styrene, polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide, polybutadiene, trans polyisoprene, fluorine Various thermoplastic elastomers such as rubber and chlorinated polyethylene, epoxy resin, phenol resin, urea resin, melamine resin, aramid resin, unsaturated poly Examples thereof include ester, silicone resin, polyurethane and the like, or resin materials such as copolymers, blends and polymer alloys mainly composed of these, or composite materials obtained by combining one or more of these materials.

Moreover, the material which gave each process, such as an oxidation process (oxide film formation), a plating process, a passivation process, a nitriding process, to the above materials may be used.
Among these, the constituent material of the substrate 20 is preferably a silicon material or stainless steel. Since such a material is excellent in chemical resistance, even if it is exposed to ink for a long time, the substrate 20 can be reliably prevented from being deteriorated or deteriorated. Moreover, since these materials are excellent in workability, the substrate 20 with high dimensional accuracy can be obtained. For this reason, the accuracy of the volume of the discharge liquid storage chamber 21 and the discharge liquid supply chamber 22 is increased, and the head 1 capable of high-quality printing is obtained.

Further, the discharge liquid supply chamber 22 communicates with a discharge liquid supply path 61 provided in a case head 60 described later, and is a part of a reservoir 70 that functions as a common ink chamber that supplies ink to the plurality of discharge liquid storage chambers 21. Parts.
Further, the inner surfaces of the discharge liquid storage chamber 21 and the discharge liquid supply chamber 22 may be subjected to a hydrophilic treatment in advance. Thereby, it is possible to prevent bubbles from being contained in the ink stored in the discharge liquid storage chamber 21 and the discharge liquid supply chamber 22.

The nozzle plate 10 is bonded (adhered) to the lower surface of the substrate 20 (the surface opposite to the sealing sheet 30) via the bonding film 15.
The droplet discharge head of the present invention is characterized by the bonding film 15 and a method of bonding the substrate 20 and the nozzle plate 10 using the bonding film 15.
The bonding film 15 includes a Si skeleton including a siloxane (Si—O) bond and a random atomic structure, and a leaving group bonded to the Si skeleton.
The bonding film 15 bonds the substrate 20 and the nozzle plate 10 with the adhesiveness developed on the surface of the bonding film 15 because the leaving group is released from the Si skeleton by applying energy.
The bonding film 15 will be described in detail later.

Nozzle holes 11 are formed (perforated) in the nozzle plate 10 so as to correspond to the respective discharge liquid storage chambers 21. By causing the nozzle hole 11 to push out the ink stored in the discharge liquid storage chamber 21, the ink can be discharged as droplets.
Further, the nozzle plate 10 constitutes the lower surface of the inner wall surface of each discharge liquid storage chamber 21 and the discharge liquid supply chamber 22. That is, the nozzle plate 10, the substrate 20, and the sealing sheet 30 define each discharge liquid storage chamber 21 and the discharge liquid supply chamber 22.

Examples of the material constituting the nozzle plate 10 include silicon materials, metal materials, glass materials, ceramic materials, carbon materials, resin materials, or one or more of these materials as described above. The composite material etc. which were combined are mentioned.
Among these, it is preferable that the constituent material of the nozzle plate 10 is a silicon material or stainless steel. Since such a material is excellent in chemical resistance, it is possible to reliably prevent the nozzle plate 10 from being altered or deteriorated even when exposed to ink for a long time. Moreover, since these materials are excellent in workability, the nozzle plate 10 with high dimensional accuracy can be obtained. For this reason, the highly reliable head 1 is obtained.

The constituent material of the nozzle plate 10 preferably has a linear expansion coefficient of 300 ° C. or less and about 2.5 to 4.5 [× 10 ⁻⁶ / ° C.].
The thickness of the nozzle plate 10 is not particularly limited, but is preferably about 0.01 to 1 mm.
Further, a liquid repellent film (not shown) is provided on the lower surface of the nozzle plate 10 as necessary. Thereby, it is possible to prevent ink droplets ejected from the nozzle holes from being ejected in unintended directions.

Examples of the constituent material of the liquid repellent film include a coupling agent having a functional group exhibiting liquid repellency, a liquid repellant resin material, and the like.
As the coupling agent, for example, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent, a zirconium coupling agent, an organic phosphate coupling agent, a silyl peroxide coupling agent, or the like is used. be able to.
Examples of the functional group exhibiting liquid repellency include a fluoroalkyl group, an alkyl group, a vinyl group, an epoxy group, a styryl group, and a methacryloxy group.

  On the other hand, examples of liquid repellent resin materials include polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), and perfluoro. Examples thereof include fluorine-based resins such as ethylene-propene copolymer (FEP) and ethylene-chlorotrifluoroethylene copolymer (ECTFE).

On the other hand, the sealing sheet 30 is bonded (adhered) to the upper surface of the substrate 20 via the bonding film 25.
Further, the sealing sheet 30 constitutes the upper surface of the inner wall surface of each discharge liquid storage chamber 21 and the discharge liquid supply chamber 22. That is, each of the discharge liquid storage chambers 21 and the discharge liquid supply chamber 22 is defined by the sealing sheet 30, the substrate 20, and the nozzle plate 10. And since the sealing sheet 30 is reliably joined to the substrate 20, the liquid tightness of each discharge liquid storage chamber 21 and the discharge liquid supply chamber 22 is secured.

As a material constituting the sealing sheet 30, for example, a silicon material, a metal material, a glass material, a ceramic material, a carbon material, a resin material, or a combination of one or more of these materials may be used. A composite material etc. are mentioned.
Among these, the constituent material of the sealing sheet 30 is preferably a resin material such as polyphenylene sulfide (PPS) or an aramid resin, a silicon material, or stainless steel. Since such a material is excellent in chemical resistance, even if it is exposed to ink for a long time, it is possible to reliably prevent the sealing sheet 30 from being altered or deteriorated. For this reason, ink can be stored in the discharge liquid storage chamber 21 and the discharge liquid supply chamber 22 for a long period of time.

  The bonding film 25 for bonding the sealing sheet 30 and the substrate 20 may be made of any material as long as it can bond or bond the substrate 20 and the sealing sheet 30. Or an adhesive such as an epoxy-based adhesive, a silicone-based adhesive, or a urethane-based adhesive, solder, a brazing material, and the like.

Further, the bonding film 25 is not necessarily provided and may be omitted. In this case, the substrate 20 and the sealing sheet 30 can be joined (adhered) by fusion (welding) or a direct joining method such as solid joining such as silicon direct joining or anodic joining.
In the present embodiment, it is assumed that the bonding film 25 has the same bonding function (adhesiveness) as the bonding film 15 described above.

That is, the bonding film 25 includes a Si skeleton including a siloxane (Si—O) bond and having a random atomic structure, and a leaving group bonded to the Si skeleton.
The bonding film 25 bonds the substrate 20 and the sealing sheet 30 with the adhesiveness developed on the surface of the bonding film 25 because the leaving group is released from the Si skeleton by applying energy.

The bonding film 25 will be described later together with the bonding film 15 described above.
The vibration plate 40 is bonded (adhered) to the upper surface of the sealing sheet 30 via the bonding film 35.
As a material constituting the diaphragm 40, for example, a silicon material, a metal material, a glass material, a ceramic material, a carbon material, a resin material, or a combination of one or more of these materials as described above is used. Materials and the like. And since the vibration plate 40 is securely joined to the sealing sheet 30, the distortion generated in the piezoelectric element 50 is reliably converted into the displacement of the sealing sheet 30, that is, the volume change of each discharge liquid storage chamber 21. is doing.

Among these, it is preferable that the constituent material of the diaphragm 40 is a silicon material or stainless steel. Such a material can be elastically deformed at a high speed. For this reason, when the piezoelectric element 50 displaces the diaphragm 40, the volume of the discharge liquid storage chamber 21 can be changed at high speed. As a result, ink can be ejected with high accuracy.
The bonding film 35 for bonding the vibration plate 40 and the sealing sheet 30 may be made of any material as long as the sealing sheet 30 and the vibration plate 40 can be bonded or bonded. Although it selects suitably by each structural material of the sealing sheet 30 and the diaphragm 40, For example, adhesives, such as an epoxy-type adhesive agent, a silicone type adhesive agent, a urethane type adhesive agent, solder, a brazing material, etc. are mentioned.

The bonding film 35 is not necessarily provided and may be omitted. In this case, the sealing sheet 30 and the diaphragm 40 can be bonded (adhered) by fusion (welding) or a direct bonding method such as solid bonding such as silicon direct bonding or anodic bonding.
In the present embodiment, it is assumed that the bonding film 35 has the same bonding function (adhesiveness) as the bonding film 15 described above.

That is, the bonding film 35 includes a Si skeleton including a siloxane (Si—O) bond and a random atomic structure, and a leaving group bonded to the Si skeleton.
The bonding film 35 is bonded with the sealing sheet 30 and the vibration plate 40 by the adhesiveness developed on the surface of the bonding film 35 because the leaving group is released from the Si skeleton by applying energy. .

The bonding film 35 will be described later together with the bonding film 15 and the bonding film 25 described above.
Moreover, in this embodiment, although the sealing board is comprised by the laminated body formed by laminating | stacking the sealing sheet 30 and the diaphragm 40, this sealing board may be 1 layer and may be 3 layers. You may be comprised with the laminated body formed by laminating | stacking the above layer.

In the case where the sealing plate is constituted by a laminate in which three or more layers are laminated, at least one pair of adjacent layers among the layers in the laminate is joined by the bonding film 35. If it exists, the dimensional accuracy of a laminated body will become high, and by extension, the dimensional accuracy of the head 1 can be raised.
A piezoelectric element (vibrating means) 50 is bonded (adhered) to a part of the upper surface of the diaphragm 40 (in FIG. 2, near the center of the upper surface of the diaphragm 40) via a bonding film 45a.

  The piezoelectric element 50 is constituted by a laminate of a piezoelectric layer 51 made of a piezoelectric material and an electrode film 52 that applies a voltage to the piezoelectric layer 51. In such a piezoelectric element 50, when a voltage is applied to the piezoelectric layer 51 through the electrode film 52, a distortion corresponding to the voltage is generated in the piezoelectric layer 51 (reverse piezoelectric effect). This distortion causes the vibration plate 40 and the sealing sheet 30 to bend (vibrate) and change the volume of the discharge liquid storage chamber 21. As described above, since the piezoelectric element 50 is reliably bonded to the vibration plate 40, the distortion generated in the piezoelectric element 50 can be caused by the displacement of the vibration plate 40 and the sealing sheet 30, and thus the discharge liquid storage chamber 21. It can be reliably converted into a volume change.

  In addition, the stacking direction of the piezoelectric layer 51 and the electrode film 52 is not particularly limited, and may be a direction parallel to the diaphragm 40 or a direction orthogonal thereto. When the stacking direction of the piezoelectric layer 51 and the electrode film 52 is a direction orthogonal to the vibration plate 40, the piezoelectric element 50 arranged in this way is particularly referred to as MLP (Multi Layer Piezo). If the piezoelectric element 50 is MLP, the displacement amount of the vibration plate 40 can be increased, and there is an advantage that the adjustment range of the ink discharge amount is large.

The surface of the piezoelectric element 50 adjacent to (in contact with) the bonding film 45a varies depending on the arrangement method of the piezoelectric element 50, but the surface on which the piezoelectric layer is exposed, the surface on which the electrode film is exposed, or the piezoelectric layer and the electrode Either side of the membrane is exposed.
As a material constituting the piezoelectric layer 51 in the piezoelectric element 50, for example, barium titanate, lead zirconate, lead zirconate titanate, zinc oxide, aluminum nitride, lithium tantalate, lithium niobate, crystal, and the like are available. Can be mentioned.

On the other hand, as a material constituting the electrode film 52, for example, various metal materials such as Fe, Ni, Co, Zn, Pt, Au, Ag, Cu, Pd, Al, W, Ti, Mo, or an alloy containing them. Is mentioned.
The bonding film 45a for bonding the piezoelectric element 50 and the diaphragm 40 may be made of any material as long as the diaphragm 40 and the piezoelectric element 50 can be bonded or bonded. For example, an adhesive such as an epoxy-based adhesive, a silicone-based adhesive, or a urethane-based adhesive, solder, a brazing material, or the like may be used.

Further, the bonding film 45a is not necessarily provided and may be omitted. In this case, the diaphragm 40 and the piezoelectric element 50 can be joined (adhered) by fusion (welding) or a direct joining method such as solid joining such as silicon direct joining or anodic joining.
In the present embodiment, it is assumed that the bonding film 45a has the same bonding function (adhesiveness) as the bonding film 15 described above.

That is, the bonding film 45a includes a Si skeleton including a siloxane (Si—O) bond and a random atomic structure, and a leaving group bonded to the Si skeleton.
The bonding film 45a bonds the vibration plate 40 and the piezoelectric element 50 by the adhesiveness developed on the surface of the bonding film 45a because the leaving group is released from the Si skeleton by applying energy.

The bonding film 45a will be described in detail later together with the bonding film 15, the bonding film 25, and the bonding film 35 described above.
Here, the diaphragm 40 described above has a concave portion 53 formed in an annular shape so as to surround a position corresponding to the piezoelectric element 50. That is, at a position corresponding to the piezoelectric element 50, a part of the diaphragm 40 is isolated in an island shape with the annular recess 53 interposed therebetween.

Note that the bonding film 45 a is provided inside the annular recess 53.
The electrode film 52 of the piezoelectric element 50 is electrically connected to a drive IC (not shown). Thereby, the operation of the drive element 50 can be controlled by the drive IC.
Further, the case head 60 is bonded (adhered) to a part of the upper surface of the vibration plate 40 via a bonding film 45b. In this way, the case head 60 is securely joined to the vibration plate 40 to reinforce a so-called cavity portion composed of a laminate of the nozzle plate 10, the substrate 20, the sealing sheet 30 and the vibration plate 40. In addition, kinking and warping of the cavity portion can be reliably suppressed.

Examples of the material constituting the case head 60 include a silicon material, a metal material, a glass material, a ceramic material, a carbon material, a resin material, or a combination of one or more of these materials as described above. Materials and the like.
Among these, the constituent material of the case head 60 is preferably polyphenylene sulfide (PPS), a modified polyphenylene ether resin such as Zylon (“Zylon” is a registered trademark), or stainless steel. Since these materials have sufficient rigidity, they are suitable as constituent materials for the case head 60 that supports the head 1.

  The bonding film 45b for bonding the case head 60 and the diaphragm 40 may be made of any material as long as the diaphragm 40 and the case head 60 can be bonded or bonded. For example, an adhesive such as an epoxy-based adhesive, a silicone-based adhesive, or a urethane-based adhesive, solder, a brazing material, or the like may be used.

Further, the bonding film 45b is not necessarily provided and may be omitted. In this case, the diaphragm 40 and the case head 60 can be joined (adhered) by fusion (welding) or a direct joining method such as solid joining such as silicon direct joining or anodic joining.
In the present embodiment, the bonding film 45b has the same bonding function (adhesiveness) as the bonding film 15 described above.

That is, the bonding film 45b includes a Si skeleton including a siloxane (Si—O) bond and having a random atomic structure, and a leaving group bonded to the Si skeleton.
The bonding film 45b bonds the vibration plate 40 and the case head 60 with the adhesiveness developed on the surface of the bonding film 45b because the leaving group is released from the Si skeleton by applying energy.

The bonding film 45b will be described in detail later together with the bonding film 15, the bonding film 25, the bonding film 35, and the bonding film 45a described above.
Further, the bonding film 25, the sealing sheet 30, the bonding film 35, the vibration plate 40, and the bonding film 45 b have through holes 23 at positions corresponding to the discharge liquid supply chamber 22. Through the through hole 23, the discharge liquid supply path 61 provided in the case head 60 and the discharge liquid supply chamber 22 communicate with each other. The discharge liquid supply path 61 and the discharge liquid supply chamber 22 constitute part of a reservoir 70 that functions as a common ink chamber that supplies ink to the plurality of discharge liquid storage chambers 21.

  In such a head 1, after taking ink from an external discharge liquid supply means (not shown) and filling the interior from the reservoir 70 to the nozzle hole 11 with the ink, each discharge liquid storage chamber 21 is received by a recording signal from the drive IC. Each piezoelectric element 50 corresponding to is operated. Thereby, the vibration plate 40 and the sealing sheet 30 are bent (vibrated) due to the reverse piezoelectric effect of the piezoelectric element 50. As a result, for example, when the volume in each discharge liquid storage chamber 21 contracts, the pressure in each discharge liquid storage chamber 21 increases instantaneously, and ink is pushed out (discharged) from the nozzle hole 11 as a droplet.

In this way, in the head 1, a voltage is applied to the piezoelectric element 50 at a position to be printed via the driving IC, that is, an arbitrary character is printed as a figure or the like by sequentially inputting ejection signals. Can do.
The head 1 is not limited to the one having the configuration described above, and may be a head having a configuration (thermal method) in which the piezoelectric element 50 is replaced with a heater as vibration means, for example. Such a head is configured to discharge ink from the nozzle hole 11 as droplets by heating the ink with a heater to boil, thereby increasing the pressure in the discharge liquid storage chamber.
Furthermore, other examples of the vibration means include an electrostatic actuator system.
Note that, as in the present embodiment, since the vibration means is configured by a piezoelectric element, the degree of bending generated in the vibration plate 40 and the sealing sheet 30 can be easily controlled. Thereby, the size of the ink droplets can be easily controlled.

Next, the bonding film used in common for the bonding film 15, the bonding film 25, the bonding film 35, the bonding film 45a, and the bonding film 45b will be described. Hereinafter, the bonding film 15 formed on the substrate 20 will be described as a representative.
The state before applying the energy of the bonding film 15 is formed by a plasma polymerization method, and as shown in FIG. 4, a Si skeleton including a siloxane (Si—O) bond 302 and having a random atomic structure. 301 and a leaving group 303 bonded to the Si skeleton 301.

When energy is applied to the bonding film 15, as shown in FIG. 5, a part of the leaving group 303 is detached from the Si skeleton 301, and an active hand 304 is generated instead. Thereby, adhesiveness is expressed on the surface of the bonding film 15. Thus, the board | substrate 20 and the nozzle plate 10 are joined by the joining film | membrane 15 which adhesiveness expressed.
Such a bonding film 15 is a strong film that is not easily deformed by the influence of the Si skeleton 301 including the siloxane bond 302 and having a random atomic structure. This is presumably because the crystallinity of the Si skeleton 301 becomes low, so that defects such as dislocations and misalignments at the grain boundaries are difficult to occur. For this reason, the distance between the substrate 20 and the nozzle plate 10 can be kept constant with high dimensional accuracy, and the volumes of the discharge liquid storage chambers 21 and the discharge liquid supply chambers 22 can be strictly controlled. . As a result, the volumes of the ejection liquid storage chambers 21 provided in plurality in the head 1 can be made uniform, and the sizes of the ink droplets ejected from the nozzle holes 11 can be made uniform. In addition, since the fixed angle of the nozzle plate 10 can be strictly controlled, the ink droplet ejection direction can be kept constant. For these reasons, the quality of printing by the ink jet printer 9 can be improved. Further, when producing a plurality of heads 1, variations in print quality for each head 1 can be suppressed, and therefore individual differences in print quality of the ink jet printer 9 can be suppressed.

In addition, since the substrate 20 and the nozzle plate 10 are bonded using the bonding film 15, there is no problem that the adhesive protrudes when the bonding is conventionally performed using the adhesive. Therefore, it is possible to avoid the protruding adhesive from blocking the ink flow path in the head 1. There is also an advantage that the trouble of removing the protruding adhesive can be omitted.
The bonding film 15 is excellent in chemical resistance due to the action of the strong Si skeleton 301 as described above. For this reason, even if the bonding film 15 is exposed to ink for a long period of time, it is prevented from being altered or deteriorated, and bonding (adhesion) between the substrate 20 and the nozzle plate 10 can be ensured for a long period of time. That is, according to the bonding film 15, since the liquid tightness of the head 1 can be sufficiently ensured, the highly reliable head 1 can be provided.

Further, the bonding film 15 has excellent heat resistance due to the action of the chemically stable Si skeleton 301. For this reason, even if the head 1 is exposed to high temperature, the bonding film 15 can be reliably prevented from being deteriorated or deteriorated.
Further, such a bonding film 15 is a solid having no fluidity. For this reason, the thickness and shape of the adhesive layer (bonding film 15) hardly change compared to a conventional liquid or viscous liquid adhesive. For this reason, the dimensional accuracy of the head 1 manufactured using the bonding film 15 is remarkably higher than the conventional one. Furthermore, since the time required for curing of the adhesive is not required, strong bonding can be achieved in a short time.

  As such a bonding film 15, among the atoms obtained by removing H atoms from all atoms constituting the bonding film 15, the total content of Si atoms and O atoms is about 10 to 90 atomic%. It is preferable and it is more preferable that it is about 20-80 atomic%. If Si atoms and O atoms are contained in the above range, the bonding film 15 forms a strong network between the Si atoms and the O atoms, and the bonding film 15 itself becomes stronger. . Further, the bonding film 15 exhibits a particularly high bonding strength with respect to the substrate 20 and the nozzle plate 10.

The abundance ratio of Si atoms and O atoms in the bonding film 15 is preferably about 3: 7 to 7: 3, and more preferably about 4: 6 to 6: 4. By setting the abundance ratio of Si atoms and O atoms to be within the above range, the stability of the bonding film 15 increases, and the substrate 20 and the nozzle plate 10 can be bonded more firmly.
Note that the crystallinity of the Si skeleton 301 in the bonding film 15 is preferably 45% or less, and more preferably 40% or less. As a result, the Si skeleton 301 includes a sufficiently random atomic structure. For this reason, the characteristics of the Si skeleton 301 described above become obvious, and the dimensional accuracy and adhesiveness of the bonding film 15 become more excellent.

  The bonding film 15 preferably includes Si—H bonds in its structure. This Si-H bond is generated in the polymer when the silane undergoes a polymerization reaction by the plasma polymerization method. At this time, if the Si-H bond inhibits the regular formation of the siloxane bond, Conceivable. For this reason, the siloxane bond is formed so as to avoid the Si—H bond, and the regularity of the atomic structure of the Si skeleton 301 is lowered. Thus, according to the plasma polymerization method, the Si skeleton 301 having a low crystallinity can be efficiently formed.

  On the other hand, the greater the Si—H bond content in the bonding film 15, the lower the crystallinity. Specifically, in the infrared absorption spectrum of the bonding film 15, when the intensity of the peak attributed to the siloxane bond is 1, the intensity of the peak attributed to the Si—H bond is about 0.001 to 0.2. It is preferable that it is about 0.002-0.05, and it is further more preferable that it is about 0.005-0.02. When the ratio of the Si—H bond to the siloxane bond is within the above range, the atomic structure in the bonding film 15 is relatively random. For this reason, when the peak intensity of the Si—H bond is within the above range with respect to the peak intensity of the siloxane bond, the bonding film 15 is particularly excellent in bonding strength, chemical resistance, and dimensional accuracy.

  Further, as described above, the leaving group 303 bonded to the Si skeleton 301 acts to generate an active hand 304 in the bonding film 15 by detaching from the Si skeleton 301. Therefore, although the leaving group 303 is relatively easily and uniformly desorbed by being given energy, it is securely bonded to the Si skeleton 301 so as not to be desorbed when no energy is given. It needs to be a thing.

  From this point of view, the leaving group 303 includes an H atom, a B atom, a C atom, an N atom, an O atom, a P atom, an S atom, and a halogen atom, or each of these atoms. What consists of at least 1 sort (s) selected from the group which consists of an atomic group arrange | positioned so that it may couple | bond with frame | skeleton 301 is used preferably. Such a leaving group 303 is relatively excellent in bond / elimination selectivity by energy application. For this reason, such a leaving group 303 can sufficiently satisfy the above-described necessity, and the adhesiveness of the bonding film 15 can be further enhanced.

  Examples of the atomic group (group) arranged so that each atom as described above is bonded to the Si skeleton 301 include, for example, an alkyl group such as a methyl group and an ethyl group, and an alkenyl group such as a vinyl group and an allyl group. Aldehyde group, ketone group, carboxyl group, amino group, amide group, nitro group, halogenated alkyl group, mercapto group, sulfonic acid group, cyano group, isocyanate group and the like.

Among these groups, the leaving group 303 is particularly preferably an alkyl group. Since the alkyl group has high chemical stability, the bonding film 15 including the alkyl group has excellent weather resistance and chemical resistance.
Here, when the leaving group 303 is a methyl group (—CH ₃ ), the preferred content is defined as follows from the peak intensity in the infrared light absorption spectrum.

That is, in the infrared absorption spectrum of the bonding film 15, when the intensity of the peak attributed to the siloxane bond is 1, the intensity of the peak attributed to the methyl group is preferably about 0.05 to 0.45. More preferably, it is about 0.1 to 0.4, and more preferably about 0.2 to 0.3. Since the ratio of the peak intensity of the methyl group to the peak intensity of the siloxane bond is within the above range, it is necessary and sufficient in the bonding film 15 while preventing the methyl group from inhibiting the generation of the siloxane bond more than necessary. Since the number of active hands is generated, sufficient adhesiveness is generated in the bonding film 15. Further, the bonding film 15 exhibits sufficient weather resistance and chemical resistance due to the methyl group.
Examples of the constituent material of the bonding film 15 having such characteristics include a polymer containing a siloxane bond such as polyorganosiloxane.

The bonding film 15 made of polyorganosiloxane itself has excellent mechanical properties. In addition, it exhibits particularly excellent adhesion to many materials. Therefore, the bonding film 15 made of polyorganosiloxane can bond the substrate 20 and the nozzle plate 10 more firmly.
Polyorganosiloxane usually exhibits water repellency (non-adhesiveness), but when given energy, it can easily desorb organic groups, changes to hydrophilicity, and exhibits adhesiveness. However, there is an advantage that the non-adhesiveness and the adhesiveness can be controlled easily and reliably.

  This water repellency (non-adhesiveness) is mainly due to the action of alkyl groups contained in the polyorganosiloxane. Therefore, the bonding film 15 made of polyorganosiloxane exhibits adhesiveness in a region to which energy is applied, and has excellent liquid repellency due to the aforementioned alkyl group in a region to which energy is not applied. Has the advantage of being Therefore, by controlling the region to which energy is applied, excellent liquid repellency can be expressed in the region of the bonding film 15 that does not contact the substrate 20 and the nozzle plate 10. As a result, the bonding film 15 provides, for example, a highly reliable head 1 having excellent durability when manufacturing the head 1 of an industrial inkjet printer that uses an organic ink that easily erodes a resin material. Can do.

  Further, among polyorganosiloxanes, those mainly composed of a polymer of octamethyltrisiloxane are preferred. The bonding film 15 mainly composed of a polymer of octamethyltrisiloxane is particularly excellent in adhesiveness, and therefore can be particularly suitably applied to the droplet discharge head of the present invention. Moreover, since the raw material which has octamethyltrisiloxane as a main component is liquid at normal temperature and has an appropriate viscosity, there is also an advantage that it is easy to handle.

The average thickness of the bonding film 15 is preferably about 1 to 1000 nm, and more preferably about 2 to 800 nm. By setting the average thickness of the bonding film 15 within the above range, the dimensional accuracy between the substrate 20 and the nozzle plate 10 can be more firmly bonded while preventing the dimensional accuracy from being significantly lowered.
That is, when the average thickness of the bonding film 15 is less than the lower limit value, there is a possibility that sufficient bonding strength cannot be obtained. On the other hand, when the average thickness of the bonding film 15 exceeds the upper limit, the dimensional accuracy of the head 1 may be significantly reduced.

  Furthermore, if the average thickness of the bonding film 15 is within the above range, a certain degree of shape followability is ensured for the bonding film 15. For this reason, for example, even when unevenness exists on the bonding surface (surface adjacent to the bonding film 15) of the substrate 20, the bonding film 15 follows the shape of the unevenness depending on the height of the unevenness. Can be applied. As a result, the bonding film 15 can absorb the unevenness and reduce the height of the unevenness generated on the surface. And when the board | substrate 20 provided with the joining film | membrane 15 and the nozzle plate 10 are bonded together, the adhesiveness with respect to the nozzle plate 10 of the joining film | membrane 15 can be improved.

In addition, the degree of the shape followability as described above becomes more prominent as the bonding film 15 is thicker. Therefore, in order to sufficiently ensure the shape following property, the thickness of the bonding film 15 should be as large as possible.
Such a bonding film 15 can be produced by applying energy to a film produced by a plasma polymerization method. According to the plasma polymerization method, finally, a dense and homogeneous bonding film 15 can be efficiently produced. As a result, the bonding film 15 produced by the plasma polymerization method can bond the substrate 20 and the nozzle plate 10 particularly firmly. Furthermore, the bonding film 15 that has been manufactured by the plasma polymerization method and has not been applied with energy can be maintained for a relatively long time after being applied with energy and activated. For this reason, the manufacturing process of the head 1 can be simplified and improved in efficiency.

Moreover, in this embodiment, since the board | substrate 20 and the sealing sheet 30 are joined via the bonding film 25, the adhesiveness between these becomes high, and each discharge liquid storage chamber 21 and the discharge liquid supply chamber 22 are sufficient. The liquid tightness can be particularly improved.
Moreover, in this embodiment, since the sealing sheet 30 and the diaphragm 40 are joined via the joining film 35, the adhesiveness between them and the distortion propagation property are enhanced. For this reason, the distortion of the piezoelectric element 50 can be reliably converted into a pressure change in each discharge liquid storage chamber 21. That is, the response of the displacement of the sealing sheet 30 and the diaphragm 40 can be enhanced.

  In this embodiment, since the diaphragm 40 and the piezoelectric element 50 are bonded via the bonding film 45a, the adhesion between them and the distortion propagation property are enhanced. Conventionally, since the piezoelectric element and the vibration plate have been bonded with an adhesive, there has been a problem that the distortion of the piezoelectric element is attenuated before the vibration plate is displaced. The distortion can be reliably converted into a pressure change in each discharge liquid storage chamber 21.

Moreover, in this embodiment, since the diaphragm 40 and the case head 60 are joined via the joining film 45b, the adhesiveness between these becomes high. For this reason, the vibration plate 40 can be reliably supported by the case head 60, and the vibration plate 40, the sealing sheet 30, the substrate 20 and the nozzle plate 10 can be prevented from being kinked or warped.
Hereinafter, a method for producing the bonding film 15 and a method for producing the head 1 including this method will be described.

6 to 9 are views (longitudinal sectional views) for explaining a method of manufacturing the ink jet recording head. In the following description, the upper side in FIGS. 6 to 9 is referred to as “upper” and the lower side is referred to as “lower”.
The manufacturing method of the head 1 according to the present embodiment includes a step of forming a bonding film 25 on the base material 20 ′, bonding the base material 20 ′ and the sealing sheet 30 through the bonding film 25, and sealing Forming a bonding film 35 on the sheet 30, bonding the sealing sheet 30 and the vibration plate 40 through the bonding film 35, and the bonding film 25, the sealing sheet 30, the bonding film 35, and the vibration plate 40. A step of forming a through hole 23 in a part and a step of forming a recess 53 in a part of the vibration plate 40, a bonding film 45a is formed on the vibration plate 40, and the vibration plate 40 and the piezoelectric film are formed via the bonding film 45a. A step of bonding the element 50, a step of forming a bonding film 45b on the vibration plate 40, a step of bonding the vibration plate 40 and the case head 60 via the bonding film 45b, and a process on the base material 20 ′. And forming a substrate 20, and a sealing sheet for the substrate 20 The bonding film 15 is formed on 30 opposite of the surface, and a step of bonding the substrate 20 and the nozzle plate 10 through the bonding film 15.

Hereinafter, each process will be described sequentially.
[1] First, a base material 20 ′ is prepared as a base material for manufacturing the substrate 20. The base material 20 ′ can be the substrate 20 by processing in a process described later.
Next, as shown in FIG. 6A, a bonding film 25 in a state before applying energy is formed on the base material 20 ′. The method for forming the bonding film 25 is the same as the method for forming the bonding film 15 described later.

[2] Next, energy is applied to the bonding film 25. Thereby, adhesiveness with the sealing sheet 30 is expressed in the bonding film 25. The application of energy to the bonding film 25 can be performed by a method similar to the method of applying energy to the bonding film 15 described later.
[3] Next, the sealing sheet 30 is prepared. And base material 20 'and the sealing sheet 30 are bonded together so that the bonding film 25 and the sealing sheet 30 which express adhesiveness closely_contact | adhere. Thereby, as shown in FIG. 6B, the base material 20 ′ and the sealing sheet 30 are bonded (adhered) via the bonding film 25.

[4] Next, as shown in FIG. 6C, a bonding film 35 in a state before applying energy is formed on the sealing sheet 30. The method for forming the bonding film 35 is the same as the method for forming the bonding film 15 described later.
[5] Next, energy is applied to the bonding film 35. Thereby, adhesiveness with the diaphragm 40 is expressed in the bonding film 35. The application of energy to the bonding film 35 can be performed by a method similar to the method of applying energy to the bonding film 15 described later.

  [6] Next, the diaphragm 40 is prepared. Then, the base material 20 ′ including the sealing sheet 30 and the vibration plate 40 are bonded together so that the bonding film 35 exhibiting adhesiveness and the vibration plate 40 are in close contact with each other. Thereby, the sealing sheet 30 and the diaphragm 40 are bonded (adhered) via the bonding film 35. As a result, as shown in FIG. 6D, the base material 20 ', the sealing sheet 30, and the diaphragm 40 are joined.

[7] Next, as shown in FIG. 6 (e), the bonding film 25, the sealing sheet 30, the bonding film 35, and the diaphragm 40 are penetrated into positions corresponding to the discharge liquid supply chamber 22 of the head 1. Holes 23 are formed.
Moreover, the recessed part 53 is formed in the cyclic | annular area | region surrounding the position where the piezoelectric element 50 is assembled among the diaphragms 40. As shown in FIG.
The through-hole 23 and the recess 53 are formed by one or more of physical etching methods such as dry etching, reactive ion etching, beam etching, and light-assisted etching, and chemical etching methods such as wet etching. They can be used in combination.

[8] Next, as shown in FIG. 6F, a bonding film 45a in a state before applying energy is formed at a position where the piezoelectric element 50 on the diaphragm 40 is assembled. The method for forming the bonding film 45a is the same as the method for forming the bonding film 15 described later.
When the bonding film 45a is partially formed in a part of the region on the vibration plate 40, for example, the bonding film 45a is passed through a mask having a window portion having a shape corresponding to the region where the bonding film 45a is to be formed. May be deposited.

[9] Next, energy is applied to the bonding film 45a. Thereby, adhesiveness with the piezoelectric element 50 is expressed in the bonding film 45a. The application of energy to the bonding film 45a can be performed by a method similar to the method of applying energy to the bonding film 15 described later.
[10] Next, the piezoelectric element 50 is prepared. Then, the vibration plate 40 and the piezoelectric element 50 are bonded together so that the bonding film 45a that exhibits adhesiveness and the piezoelectric element 50 are in close contact with each other. Thereby, the diaphragm 40 and the piezoelectric element 50 are bonded (adhered) via the bonding film 45a. As a result, as shown in FIG. 7G, the base material 20 ′, the sealing sheet 30, the vibration plate 40, and the piezoelectric element 50 are joined.

[11] Next, as shown in FIG. 7H, a bonding film 45 b in a state before energy is applied is formed at a position where the case head 60 is assembled on the diaphragm 40. The method for forming the bonding film 45b is the same as the method for forming the bonding film 15 described later.
When the bonding film 45b is partially formed in a part of the region on the vibration plate 40, for example, the bonding film 45b is passed through a mask having a window portion having a shape corresponding to the region where the bonding film 45b is to be formed. May be deposited.

[12] Next, energy is applied to the bonding film 45b. Thereby, adhesiveness with the case head 60 is expressed in the bonding film 45b. The application of energy to the bonding film 45b can be performed by a method similar to the method of applying energy to the bonding film 15 described later.
[13] Next, the case head 60 is prepared. Then, the vibration plate 40 and the case head 60 are bonded together so that the bonding film 45b that exhibits adhesiveness and the case head 60 are in close contact with each other. Thereby, the diaphragm 40 and the case head 60 are bonded (adhered) via the bonding film 45b. As a result, as shown in FIG. 7I, the base material 20 ′, the sealing sheet 30, the vibration plate 40, the piezoelectric element 50, and the case head 60 are joined.

  [14] Next, the base material 20 ′ to which the sealing sheet 30, the vibration plate 40, the piezoelectric element 50, and the case head 60 are joined is turned upside down. Then, the surface of the base material 20 ′ opposite to the sealing sheet 30 is processed to form each discharge liquid storage chamber 21 and the discharge liquid supply chamber 22. Thereby, the substrate 20 is obtained from the base material 20 '(see FIG. 8J). The discharge liquid supply chamber 22 communicates with the bonding film 25, the sealing sheet 30, the bonding film 35, the through-hole 23 formed in the vibration plate 40, and the discharge liquid supply path 61 provided in the case head 60. A reservoir 70 is formed.

As the processing method of the base material 20 ′, for example, various etching methods as described above can be used.
Here, each of the discharge liquid storage chambers 21 and the discharge liquid supply chambers 22 is processed by processing the base material 20 ′ to which the sealing sheet 30, the vibration plate 40, the piezoelectric element 50, and the case head 60 are bonded. However, the discharge liquid storage chambers 21 and the discharge liquid supply chambers 22 may be provided in the base material 20 ′ in advance at the time of the step [1].

[15] Next, the nozzle plate 10 is bonded on the surface of the substrate 20 opposite to the sealing sheet 30. Hereinafter, a method of joining the substrate 20 and the nozzle plate 10 will be described in detail.
First, the bonding film 15 in a state before applying energy is formed on the substrate 20 to which the sealing sheet 30, the vibration plate 40, the piezoelectric element 50, and the case head 60 are bonded by plasma polymerization. In the plasma polymerization method, for example, a mixed gas of a source gas and a carrier gas is supplied in a strong electric field to polymerize molecules in the source gas and deposit a polymer on the substrate 20 to obtain a film. It is.

Hereinafter, a method for forming the bonding film 15 by the plasma polymerization method will be described in detail. First, prior to explaining the method for forming the bonding film 15, the plasma polymerization method is performed on the substrate 20 to form the bonding film 15. A plasma polymerization apparatus used for manufacturing will be described, and then a method for forming the bonding film 15 will be described.
FIG. 10 is a longitudinal sectional view schematically showing a plasma polymerization apparatus used for producing a bonding film included in the ink jet recording head according to the present embodiment. In the following description, the upper side in FIG. 10 is referred to as “upper” and the lower side is referred to as “lower”.

  The plasma polymerization apparatus 100 shown in FIG. 10 includes a chamber 101, a first electrode 130 that supports the substrate 20, a second electrode 140, and a power supply circuit 180 that applies a high-frequency voltage between the electrodes 130 and 140. A gas supply unit 190 that supplies gas into the chamber 101 and an exhaust pump 170 that exhausts the gas in the chamber 101 are provided. Among these parts, the first electrode 130 and the second electrode 140 are provided in the chamber 101. Hereinafter, each part will be described in detail.

The chamber 101 is a container that can keep the inside airtight, and is used with the inside being in a reduced pressure (vacuum) state. Therefore, the chamber 101 has pressure resistance that can withstand a pressure difference between the inside and the outside.
A chamber 101 shown in FIG. 10 has a substantially cylindrical chamber body whose axis is arranged along the horizontal direction, a circular side wall that seals the left-side opening of the chamber body, and a circle that seals the right-side opening. And side walls.

A supply port 103 is provided above the chamber 101, and an exhaust port 104 is provided below the chamber 101. A gas supply unit 190 is connected to the supply port 103, and an exhaust pump 170 is connected to the exhaust port 104.
In this embodiment, the chamber 101 is made of a highly conductive metal material and is electrically grounded via the ground wire 102.

The first electrode 130 has a plate shape and supports the substrate 20.
The first electrode 130 is provided on the inner wall surface of the side wall of the chamber 101 along the vertical direction, whereby the first electrode 130 is electrically grounded via the chamber 101. The first electrode 130 is provided concentrically with the chamber body as shown in FIG.

An electrostatic chuck (suction mechanism) 139 is provided on the surface of the first electrode 130 that supports the substrate 20.
The electrostatic chuck 139 can support the substrate 20 along the vertical direction as shown in FIG. Further, even if the substrate 20 has a slight warp, the substrate 20 can be subjected to plasma processing in a state where the warp is corrected by being attracted to the electrostatic chuck 139.

The second electrode 140 is provided to face the first electrode 130 with the substrate 20 interposed therebetween. Note that the second electrode 140 is provided in a state of being separated (insulated) from the inner wall surface of the side wall of the chamber 101.
A high frequency power source 182 is connected to the second electrode 140 via a wiring 184. A matching box (matching unit) 183 is provided in the middle of the wiring 184. The wiring 184, the high-frequency power source 182 and the matching box 183 constitute a power circuit 180.

According to such a power supply circuit 180, since the first electrode 130 is grounded, a high frequency voltage is applied between the first electrode 130 and the second electrode 140. As a result, an electric field whose direction is reversed at a high frequency is induced in the gap between the first electrode 130 and the second electrode 140.
The gas supply unit 190 supplies a predetermined gas into the chamber 101.

  A gas supply unit 190 shown in FIG. 10 stores a liquid storage unit 191 that stores a liquid film material (raw material liquid), a vaporizer 192 that vaporizes the liquid film material to change it into a gaseous state, and stores a carrier gas. And a gas cylinder 193. Each of these parts and the supply port 103 of the chamber 101 are connected by a pipe 194, and a mixed gas of a gaseous film material (raw material gas) and a carrier gas is supplied from the supply port 103 into the chamber 101. It is configured to supply.

The liquid film material stored in the liquid storage unit 191 is a raw material that is polymerized by the plasma polymerization apparatus 100 to form a polymer film on the surface of the substrate 20.
Such a liquid film material is vaporized by the vaporizer 192 and is supplied into the chamber 101 as a gaseous film material (raw material gas). The source gas will be described in detail later.

The carrier gas stored in the gas cylinder 193 is a gas that is discharged due to the action of an electric field and introduced to maintain this discharge. Examples of such a carrier gas include Ar gas and He gas.
A diffusion plate 195 is provided near the supply port 103 in the chamber 101.

The diffusion plate 195 has a function of promoting the diffusion of the mixed gas supplied into the chamber 101. Thereby, the mixed gas can be dispersed in the chamber 101 with a substantially uniform concentration.
The exhaust pump 170 exhausts the inside of the chamber 101, and includes, for example, an oil rotary pump, a turbo molecular pump, or the like. Thus, by exhausting the chamber 101 and reducing the pressure, the gas can be easily converted into plasma. Further, contamination and oxidation of the substrate 20 due to contact with the air atmosphere can be prevented, and reaction products resulting from the plasma treatment can be effectively removed from the chamber 101.
The exhaust port 104 is provided with a pressure control mechanism 171 that adjusts the pressure in the chamber 101. Thereby, the pressure in the chamber 101 is appropriately set according to the operation state of the gas supply unit 190.

Next, a method for forming the bonding film 15 on the substrate 20 to which the sealing sheet 30, the vibration plate 40, the piezoelectric element 50, and the case head 60 are bonded will be described.
[15-1] First, the substrate 20 is housed in the chamber 101 of the plasma polymerization apparatus 100 so that the case head 60 is on the lower side. To a reduced pressure state.

Next, the gas supply unit 190 is operated to supply a mixed gas of the source gas and the carrier gas into the chamber 101. The supplied mixed gas is filled in the chamber 101.
Here, the ratio (mixing ratio) of the source gas in the mixed gas is slightly different depending on the type of the source gas and the carrier gas, the target film forming speed, and the like. For example, the ratio of the source gas in the mixed gas is 20 It is preferable to set to about -70%, and it is more preferable to set to about 30-60%. As a result, it is possible to optimize the conditions for formation (film formation) of the polymer film.

Further, the flow rate of the gas to be supplied is appropriately determined depending on the type of gas, the target film formation rate, the film thickness, etc., and is not particularly limited, but usually the flow rates of the source gas and the carrier gas are respectively , Preferably about 1 to 100 ccm, more preferably about 10 to 60 ccm.
Next, the power supply circuit 180 is activated, and a high frequency voltage is applied between the pair of electrodes 130 and 140. As a result, gas molecules existing between the pair of electrodes 130 and 140 are ionized to generate plasma. Molecules in the source gas are polymerized by the energy of the plasma, and the polymer is adhered and deposited on the substrate 20. As a result, as shown in FIG. 8 (k), a bonding film 15 made of a plasma polymerized film is formed on the substrate 20.
Further, the surface of the substrate 20 is activated and cleaned by the action of plasma. For this reason, the polymer of the source gas is easily deposited on the surface of the substrate 20, and the bonding film 15 can be stably formed. As described above, according to the plasma polymerization method, the adhesion strength between the substrate 20 and the bonding film 15 can be further increased regardless of the constituent material of the substrate 20.

Examples of the source gas include organosiloxanes such as methylsiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, decamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, and methylphenylsiloxane.
The plasma polymerized film obtained by using such a raw material gas, that is, the bonding film 15 is composed of a polymer obtained by polymerizing these raw materials, that is, a polyorganosiloxane.

In the plasma polymerization, the frequency of the high frequency applied between the pair of electrodes 130 and 140 is not particularly limited, but is preferably about 1 kHz to 100 MHz, and more preferably about 10 to 60 MHz.
Further, the power density of the high frequency is not particularly limited, and is preferably about 0.01~100W / cm ^2, more preferably about ^{0.1~50W / cm 2, 1~40W / cm} 2 More preferably, it is about. By setting the high-frequency power density within the above range, the Si skeleton 301 having a random atomic structure can be reliably secured while preventing the plasma gas from being added to the source gas more than necessary because the high-frequency power density is too high. Can be formed. That is, when the high-frequency output density is lower than the lower limit value, a polymerization reaction cannot be caused in the molecules in the raw material gas, and the bonding film 15 may not be formed. On the other hand, when the power density of the high frequency exceeds the upper limit, the structure that can be the leaving group 303 is separated from the Si skeleton 301 due to decomposition of the source gas, and the leaving group in the resulting bonding film 15 is separated. There is a possibility that the content of 303 is remarkably lowered, or the randomness of the Si skeleton 301 is lowered (regularity is increased).

Further, the pressure in the chamber 101 during film formation is preferably about 133.3 × 10 ^{−5 to} 1333 Pa (1 × 10 ^{−5 to} 10 Torr), and 133.3 × 10 ^{−4 to} 133.3 Pa ( More preferably, it is about 1 × 10 ^{−4 to} 1 Torr).
The raw material gas flow rate is preferably about 0.5 to 200 sccm, and more preferably about 1 to 100 sccm. On the other hand, the carrier gas flow rate is preferably about 5 to 750 sccm, and more preferably about 10 to 500 sccm.

  The treatment time is preferably about 1 to 10 minutes, more preferably about 4 to 7 minutes. Note that the thickness of the bonding film 15 formed is mainly proportional to the processing time. Therefore, the thickness of the bonding film 15 can be easily adjusted only by adjusting the processing time. For this reason, conventionally, when the substrate and the nozzle plate are bonded using an adhesive, the thickness of the adhesive cannot be strictly controlled. Therefore, the distance between the substrate 20 and the nozzle plate 10 can be strictly controlled.

Moreover, it is preferable that the temperature of the board | substrate 20 is 25 degreeC or more, and it is more preferable that it is about 25-100 degreeC.
The bonding film 15 can be obtained as described above.
In the case where the bonding film 15 is partially formed only in the region where the nozzle plate 10 is bonded on the upper surface of the substrate 20, for example, a mask having a window portion having a shape corresponding to this region is used. The bonding film 15 may be formed.

[15-2] Next, energy is applied to the bonding film 15 formed on the substrate 20.
When energy is applied, the leaving group 303 is detached from the Si skeleton 301 in the bonding film 15 as shown in FIG. Then, after the leaving group 303 is removed, active hands 304 are generated on the surface and inside of the bonding film 15 as shown in FIG. Thereby, adhesiveness with the nozzle plate 10 is expressed on the surface of the bonding film 15.

Here, the energy applied to the bonding film 15 may be applied by any method. For example, (I) a method of irradiating the bonding film 15 with energy rays, (II) a method of heating the bonding film 15, (III ) Representative examples include a method of applying a compressive force (applying physical energy) to the bonding film 15, a method of exposing to plasma (applying plasma energy), and a method of exposing to ozone gas (applying chemical energy). Method).
Among these, as a method for applying energy to the bonding film 15, it is particularly preferable to use at least one of the methods (I), (II), and (III). Since these methods can apply energy to the bonding film 15 relatively easily and efficiently, they are suitable as energy application methods.

Hereinafter, the methods (I), (II), and (III) will be described in detail.
(I) In the case of irradiating the bonding film 15 with energy rays, examples of the energy rays include light such as ultraviolet rays and laser light, particle rays such as X-rays, γ rays, electron beams, and ion beams, and the like. A combination of these energy rays.
Among these energy rays, it is particularly preferable to use ultraviolet rays having a wavelength of about 150 to 300 nm (see FIG. 8L). According to such ultraviolet rays, the amount of energy applied is optimized, so that the Si skeleton 301 in the bonding film 15 is prevented from being destroyed more than necessary, and between the Si skeleton 301 and the leaving group 303. Can be selectively cleaved. Thereby, adhesiveness can be expressed in the bonding film 15 while preventing the characteristics (mechanical characteristics, chemical characteristics, etc.) of the bonding film 15 from deteriorating.

In addition, since ultraviolet rays can be processed in a short time without unevenness, the leaving group 303 can be efficiently eliminated. Furthermore, ultraviolet rays also have the advantage that they can be generated with simple equipment such as UV lamps.
The wavelength of ultraviolet light is more preferably about 160 to 200 nm.
In the case of using the UV lamp, the output may vary depending on the area of the bonding film 15 is preferably from ^1mW / cm ^{2 ~1W} / cm 2 or ^so, at 5mW / cm ² ~50mW / cm 2 of about More preferably. In this case, the separation distance between the UV lamp and the bonding film 15 is preferably about 3 to 3000 mm, and more preferably about 10 to 1000 mm.

  Further, the time for irradiating the ultraviolet light is such a time that the leaving group 303 near the surface of the bonding film 15 can be released, that is, a time that does not allow a large amount of the leaving group 303 inside the bonding film 15 to be released. It is preferable to do this. Specifically, although it varies slightly depending on the amount of ultraviolet light, the constituent material of the bonding film 15, etc., it is preferably about 0.5 to 30 minutes, more preferably about 1 to 10 minutes.

Moreover, although an ultraviolet-ray may be irradiated continuously in time, you may irradiate intermittently (pulse form).
On the other hand, examples of the laser light include an excimer laser (femtosecond laser), an Nd-YAG laser, an Ar laser, a CO ₂ laser, and a He—Ne laser.

  The bonding film 15 may be irradiated with energy rays in any atmosphere. Specifically, the bonding film 15 may be air, an oxidizing gas atmosphere such as oxygen, a reducing gas atmosphere such as hydrogen, nitrogen, An inert gas atmosphere such as argon, or a reduced pressure (vacuum) atmosphere in which these atmospheres are decompressed may be mentioned, and it is particularly preferable to perform in an air atmosphere. Thereby, it is not necessary to spend time and cost to control the atmosphere, and irradiation of energy rays can be performed more easily.

As described above, according to the method of irradiating the energy beam, it is possible to easily apply energy selectively to the bonding film 15. For example, it is possible to prevent deterioration or deterioration of the substrate 20 due to energy application. Can do.
Moreover, according to the method of irradiating energy rays, the magnitude of energy to be applied can be easily adjusted with high accuracy. For this reason, it is possible to adjust the desorption amount of the leaving group 303 desorbed from the bonding film 15. By adjusting the amount of elimination of the leaving group 303 in this way, the bonding strength between the bonding film 15 and the nozzle plate 10 can be easily controlled.

That is, by increasing the amount of elimination of the leaving group 303, more active hands are generated on the surface and inside of the bonding film 15, so that the adhesiveness expressed in the bonding film 15 can be further improved. On the other hand, by reducing the amount of elimination of the leaving group 303, the number of active hands generated on the surface and inside of the bonding film 15 can be reduced, and the adhesiveness developed in the bonding film 15 can be suppressed.
In addition, in order to adjust the magnitude | size of the energy to provide, what is necessary is just to adjust conditions, such as the kind of energy beam, the output of an energy beam, the irradiation time of an energy beam.
Furthermore, according to the method of irradiating energy rays, a large amount of energy can be applied in a short time, so that the energy can be applied more efficiently.

(II) When the bonding film 15 is heated (not shown), the heating temperature is preferably set to about 25 to 100 ° C, more preferably about 50 to 100 ° C. By heating at a temperature in such a range, the bonding film 15 can be reliably activated while reliably preventing the substrate 20 and the like from being altered or deteriorated by heat.
The heating time may be a time that can break the molecular bond of the bonding film 15, and specifically, it is preferably about 1 to 30 minutes if the heating temperature is within the above range.

The bonding film 15 may be heated by any method, but can be heated by various heating methods such as a method using a heater, a method of irradiating infrared rays, and a method of contacting with a flame.
When the thermal expansion coefficients of the substrate 20 and the nozzle plate 10 are substantially equal, the bonding film 15 may be heated under the above conditions, but the thermal expansion coefficients of the substrate 20 and the nozzle plate 10 are different from each other. In this case, as will be described in detail later, it is preferable to perform bonding at as low a temperature as possible. By performing the bonding at a low temperature, it is possible to further reduce the thermal stress generated at the bonding interface.

  (III) In the present embodiment, the case where energy is applied to the bonding film 15 before the substrate 20 and the nozzle plate 10 are bonded to each other has been described. 10 may be performed after overlapping 10. That is, after the bonding film 15 is formed on the substrate 20 and before the energy is applied, the substrate 20 and the nozzle plate 10 are overlapped so that the bonding film 15 and the nozzle plate 10 are in close contact with each other. And By applying energy to the bonding film 15 in the temporary bonded body, the bonding film 15 exhibits adhesiveness, and the substrate 20 and the nozzle plate 10 are bonded (adhered) via the bonding film 15. The

In this case, the application of energy to the bonding film 15 in the temporary bonded body may be the methods (I) and (II) described above, but the method of applying a compressive force to the bonding film 15 may also be used.
In this case, the substrate 20 and the nozzle plate 10 are preferably compressed at a pressure of about 0.2 to 10 MPa and more preferably compressed at a pressure of about 1 to 5 MPa in a direction in which the substrate 20 and the nozzle plate 10 approach each other. As a result, it is possible to easily apply an appropriate energy to the bonding film 15 by simply compressing, and the bonding film 15 exhibits sufficient adhesiveness. The pressure may exceed the upper limit, but depending on the constituent materials of the substrate 20 and the nozzle plate 10, the substrate 20 and the nozzle plate 10 may be damaged.

The time for applying the compressive force is not particularly limited, but is preferably about 10 seconds to 30 minutes. In addition, what is necessary is just to change suitably the time which provides compression force according to the magnitude | size of compression force. Specifically, the time for applying the compressive force can be shortened as the compressive force increases.
In addition, in the state of a temporary joined body, since between the board | substrate 20 and the nozzle plate 10 is not joined, these relative positions can be adjusted (shifted) easily. Therefore, once the temporary joined body is obtained, the assembly accuracy (dimensional accuracy) of the finally obtained head 1 can be reliably increased by finely adjusting the relative position between the substrate 20 and the nozzle plate 10. .

Energy can be imparted to the bonding film 15 by the methods (I), (II), and (III) as described above.
Note that energy may be applied to the entire surface of the bonding film 15, but it may be applied to only a part of the region. In this way, the region where the adhesiveness of the bonding film 15 is expressed can be controlled, and the local concentration of stress generated at the bonding interface can be reduced by appropriately adjusting the area, shape, etc. of this region. Can do. Thereby, even when the thermal expansion coefficient difference of the board | substrate 20 and the nozzle plate 10 is large, these can be joined reliably, for example.

  Here, as described above, the bonding film 15 in a state before energy is applied has the Si skeleton 301 and the leaving group 303 as shown in FIG. When energy is applied to the bonding film 15, the leaving group 303 (in this embodiment, a methyl group) is detached from the Si skeleton 301. As a result, as shown in FIG. 5, active hands 304 are generated on the surface 31 of the bonding film 15 and activated. As a result, adhesiveness is developed on the surface of the bonding film 15.

  Here, “activating” the bonding film 15 means that the surface 31 of the bonding film 15 and the leaving group 303 in the bonding film 15 are removed, and a bond that is not terminated in the Si skeleton 301 (hereinafter referred to as “unbonded”). It is also referred to as a “hand” or “dangling bond”), a state in which this unbonded hand is terminated by a hydroxyl group (OH group), or a state in which these states are mixed.

Therefore, the active hand 304 means a dangling bond (dangling bond) or a dangling bond terminated by a hydroxyl group. According to such an active hand 304, particularly strong bonding to the nozzle plate 10 is possible.
The latter state (state in which dangling bonds are terminated by a hydroxyl group) is obtained by, for example, irradiating the bonding film 15 with energy rays in the atmospheric air, so that moisture in the atmosphere terminates dangling bonds. Can be easily generated.

[15-3] Next, the nozzle plate 10 is prepared. Then, as shown in FIG. 9 (m), the substrate 20 and the nozzle plate 10 are bonded together so that the bonding film 15 exhibiting adhesiveness and the nozzle plate 10 are in close contact with each other. As a result, the substrate 20 and the nozzle plate 10 are bonded (adhered) via the bonding film 15 as shown in FIG.
Here, it is preferable that the thermal expansion coefficients of the substrate 20 and the nozzle plate 10 to be joined as described above are substantially equal. If the coefficients of thermal expansion of the substrate 20 and the nozzle plate 10 are substantially equal, when they are bonded together, it is difficult for stress associated with thermal expansion to occur at the bonding interface. As a result, in the finally obtained head 1, it is possible to reliably prevent problems such as peeling.

Even when the thermal expansion coefficients of the substrate 20 and the nozzle plate 10 are different from each other, by optimizing the conditions for bonding the substrate 20 and the nozzle plate 10 as follows, the substrate 20 and the nozzle plate 10 Can be firmly joined with high dimensional accuracy.
That is, when the thermal expansion coefficients of the substrate 20 and the nozzle plate 10 are different from each other, it is preferable to perform bonding at as low a temperature as possible. By performing the bonding at a low temperature, it is possible to further reduce the thermal stress generated at the bonding interface.

  Specifically, depending on the difference in thermal expansion coefficient between the substrate 20 and the nozzle plate 10, the substrate 20 and the nozzle plate 10 are placed under the state where the temperature of the substrate 20 and the nozzle plate 10 is about 25 to 50 ° C. It is preferable to bond together, and it is more preferable to bond together in the state which is about 25-40 degreeC. Within such a temperature range, even if the difference in thermal expansion coefficient between the substrate 20 and the nozzle plate 10 is large to some extent, the thermal stress generated at the bonding interface can be sufficiently reduced. As a result, it is possible to reliably prevent the head 1 from warping or peeling.

In this case, when the difference in thermal expansion coefficient between the substrate 20 and the nozzle plate 10 is 5 × 10 ⁻⁵ / K or more, the bonding is performed at the lowest possible temperature as described above. It is particularly recommended. By using the bonding film 15, the substrate 20 and the nozzle plate 10 can be firmly bonded even at a low temperature as described above.

The substrate 20 and the nozzle plate 10 preferably have different rigidity. Thereby, the board | substrate 20 and the nozzle plate 10 can be joined more firmly.
In addition, it is preferable to perform a surface treatment for improving adhesion to the bonding film 15 in advance on the region of the substrate 20 where the bonding film 15 is formed. As a result, the bonding strength between the substrate 20 and the bonding film 15 can be further increased, and finally the bonding strength between the substrate 20 and the nozzle plate 10 can be increased.

  Examples of the surface treatment include physical surface treatment such as sputtering treatment and blast treatment, plasma treatment using oxygen plasma, nitrogen plasma, etc., corona discharge treatment, etching treatment, electron beam irradiation treatment, ultraviolet irradiation treatment, ozone Examples include chemical surface treatment such as exposure treatment, or a combination of these. By performing such treatment, the region of the substrate 20 where the bonding film 15 is formed can be cleaned and the region can be activated.

Further, by using plasma treatment among these surface treatments, the surface of the substrate 20 can be particularly optimized in order to form the bonding film 15.
When the substrate 20 to be surface-treated is made of a resin material (polymer material), corona discharge treatment, nitrogen plasma treatment, etc. are particularly preferably used.
Further, depending on the constituent material of the substrate 20, there is a material in which the bonding strength of the bonding film 15 is sufficiently high without performing the above-described surface treatment. Examples of the constituent material of the substrate 20 that can obtain such an effect include those mainly composed of various metal-based materials, various silicon-based materials, various glass-based materials and the like as described above.

The surface of the substrate 20 made of such a material is covered with an oxide film, and a relatively highly active hydroxyl group is bonded to the surface of the oxide film. Therefore, when the substrate 20 made of such a material is used, the substrate 20 and the bonding film 15 can be firmly adhered without performing the surface treatment as described above.
In this case, the entire substrate 20 may not be made of the material as described above, and at least the vicinity of the surface of the region where the bonding film 15 is formed needs to be made of the material as described above.

Further, when the region where the bonding film 15 of the substrate 20 is formed includes the following groups and substances, the bonding strength between the substrate 20 and the bonding film 15 is sufficient even without performing the surface treatment as described above. Can be high.
Examples of such groups and substances include functional groups such as hydroxyl groups, thiol groups, carboxyl groups, amino groups, nitro groups, and imidazole groups, radicals, ring-opened molecules, double bonds, and triple bonds. And at least one group or substance selected from the group consisting of a saturated bond, a halogen such as F, Cl, Br, and I, and a peroxide.

Further, it is preferable to appropriately select and perform various surface treatments as described above so that a surface having such a material can be obtained.
In place of the surface treatment, it is preferable to form an intermediate layer in advance in at least the region of the substrate 20 where the bonding film 15 is formed.
The intermediate layer may have any function. For example, a layer having a function of improving adhesion to the bonding film 15, a cushioning function (buffer function), a function of reducing stress concentration, and the like are preferable. By forming the bonding film 15 on the substrate 20 through such an intermediate layer, the bonding strength between the substrate 20 and the bonding film 15 is increased, and a highly reliable bonded body, that is, the head 1 can be obtained. .

Examples of the constituent material of the intermediate layer include metal materials such as aluminum and titanium, metal oxides, oxide materials such as silicon oxide, metal nitrides, and nitride materials such as silicon nitride. , Carbon-based materials such as graphite and diamond-like carbon, silane coupling agents, thiol-based compounds, metal alkoxides, and self-assembled film materials such as metal-halogen compounds. A combination of more than one species can be used.
Further, among the intermediate layers formed of these materials, the intermediate layer formed of the oxide-based material can particularly increase the bonding strength between the substrate 20 and the bonding film 15.

On the other hand, it is preferable to perform a surface treatment for improving the adhesion with the bonding film 15 in advance on the region of the nozzle plate 10 that is in contact with the bonding film 15. As a result, the bonding strength between the nozzle plate 10 and the bonding film 15 can be further increased.
For this surface treatment, the same treatment as the above-described surface treatment performed on the substrate 20 can be applied.

Moreover, it is preferable to form an intermediate layer having a function of improving the adhesion with the bonding film 15 in advance in a region of the nozzle plate 10 that contacts the bonding film 15 instead of the surface treatment. As a result, the bonding strength between the nozzle plate 10 and the bonding film 15 can be further increased.
As the constituent material of the intermediate layer, the same constituent material as that of the intermediate layer formed on the substrate 20 can be used.

Needless to say, the surface treatment and the formation of the intermediate layer on the substrate 20 and the nozzle plate 10 may be performed on the sealing sheet 30, the vibration plate 40, the piezoelectric element 50, and the case head 60. Thereby, the joint strength of each part can be raised more.
Here, a mechanism in which the substrate 20 including the bonding film 15 and the nozzle plate 10 are bonded in this step will be described.

  For example, the case where a hydroxyl group is exposed in the region of the nozzle plate 10 that is bonded to the substrate 20 will be described as an example. 20 and the nozzle plate 10 are bonded together, the hydroxyl group present on the surface 31 of the bonding film 15 and the hydroxyl group present in the region of the nozzle plate 10 are attracted to each other by hydrogen bonding, and there is an attractive force between the hydroxyl groups. appear. It is presumed that the substrate 20 provided with the bonding film 15 and the nozzle plate 10 are bonded by this attractive force.

Further, the hydroxyl groups attracting each other by this hydrogen bond are dehydrated and condensed depending on the temperature condition or the like. As a result, at the contact interface between the bonding film 15 and the nozzle plate 10, the bonds in which the hydroxyl groups are bonded are bonded through oxygen atoms. Accordingly, it is presumed that the substrate 20 and the nozzle plate 10 are bonded more firmly through the bonding film 15.
Note that the active state of the surface of the bonding film 15 activated in the step [15-2] relaxes with time. For this reason, it is preferable to perform this process [15-3] as soon as possible after completion | finish of the said process [15-2]. Specifically, after the completion of the step [15-2], the step [15-3] is preferably performed within 60 minutes, and more preferably within 5 minutes. If it is within this time, the surface of the bonding film 15 is maintained in a sufficiently active state. Therefore, when the substrate 20 provided with the bonding film 15 and the nozzle plate 10 are bonded together in this step, the bonding film 15 is sufficiently between them. Can obtain a high bonding strength.

The bonding strength between the substrate 20 and the nozzle plate 10 bonded in this manner is preferably 5 MPa (50 kgf / cm ² ) or more, more preferably 10 MPa (100 kgf / cm ² ) or more. . With such a bonding strength, peeling of the bonding interface can be sufficiently prevented. A highly reliable head 1 can be obtained.
The head 1 is manufactured through the steps as described above.

In the above description, the case where the substrate 20 and the nozzle plate 10 are bonded so that the bonding film 15 formed on the substrate 20 and the nozzle plate 10 are in close contact with each other is described. Alternatively, the substrate 20 and the nozzle plate 10 may be bonded together so that the bonding film 15 and the substrate 20 formed in close contact with each other.
Further, the bonding film 15 may be formed on both the substrate 20 and the nozzle plate 10.

FIG. 11 is a diagram illustrating another configuration example of the head according to the present embodiment. In the following description, the upper side in FIG. 11 is referred to as “upper” and the lower side is referred to as “lower”.
In the head 1 shown in FIG. 11, the substrate 20 and the nozzle plate 10 are placed so that the bonding film 15 formed on the lower surface of the substrate 20 and the bonding film 15 formed on the upper surface of the nozzle plate 10 are in close contact with each other. These are bonded (adhered) by bonding.

Similarly, in the head 1 shown in FIG. 11, the bonding film 25 formed on the upper surface of the substrate 20 and the bonding film 25 formed on the lower surface of the sealing sheet 30 are in close contact with each other. By bonding the substrate 20 and the sealing sheet 30 together, they are bonded (adhered).
Further, the sealing sheet 30 and the vibration plate 40 are bonded so that the bonding film 35 formed on the upper surface of the sealing sheet 30 and the bonding film 35 formed on the lower surface of the vibration plate 40 are in close contact with each other. Thus, they are bonded (adhered).

Further, the vibration plate 40 and the piezoelectric element 50 are bonded together so that the bonding film 45a formed on the upper surface of the vibration plate 40 and the bonding film 45a formed on the lower surface of the piezoelectric element 50 are in close contact with each other. These are joined (adhered).
Further, the vibration plate 40 and the case head 60 are bonded together so that the bonding film 45b formed on the upper surface of the vibration plate 40 and the bonding film 45b formed on the lower surface of the case head 60 are in close contact with each other. These are joined (adhered).

According to the head 1 having such a configuration, the interfaces of the respective parts can be joined more firmly. In such a head 1, since the material of the adherend (for example, the substrate, the nozzle plate, the sealing sheet, the vibration plate, the piezoelectric element, the case head, etc.) hardly affects the bonding strength, Regardless of the material, a highly reliable head 1 in which the respective parts are firmly bonded can be obtained.
In this case, for example, application of energy to the bonding film 15 is performed on each of the bonding film 15 formed on the lower surface of the substrate 20 and the bonding film 15 formed on the upper surface of the nozzle plate 10. You can do it.
In addition, after obtaining the head 1, if necessary, at least one of the following two steps ([16A] and [16B]) (a step of increasing the bonding strength of the head 1) for the head 1 ) May be performed. Thereby, the joint strength of each part of the head 1 can be further improved.

[16A] The obtained head 1 is compressed so that the nozzle plate 10, the substrate 20, the sealing sheet 30, the vibration plate 40, and the case head 60 approach each other.
Thereby, the surface of each said part and the surface of the adjacent joining film | membrane come closer, and the joint strength in the head 1 can be raised more.

Further, by pressurizing the head 1, the gap remaining at the bonding interface in the head 1 can be crushed and the bonding area can be further expanded. Thereby, the joint strength in the head 1 can be further increased.
At this time, the pressure when pressurizing the head 1 is a pressure that does not damage the head 1 and is preferably as high as possible. Thereby, the joint strength in the head 1 can be increased in proportion to this pressure.

In addition, what is necessary is just to adjust this pressure suitably according to conditions, such as a constituent material and shape of each part of the head 1, and a joining apparatus. Specifically, although it varies slightly depending on the above conditions, it is preferably about 0.2 to 10 MPa, and more preferably about 1 to 5 MPa. Thereby, the joining strength of the head 1 can be reliably increased. The pressure may exceed the upper limit, but the head 1 may be damaged depending on the constituent material of each part of the head 1.
The time for pressurization is not particularly limited, but is preferably about 10 seconds to 30 minutes. In addition, what is necessary is just to change suitably the time to pressurize according to the pressure at the time of pressurizing. Specifically, the higher the pressure at which the head 1 is pressed, the more the bonding strength can be improved even if the pressing time is shortened.

[16B] The obtained head 1 is heated.
Thereby, the joint strength in the head 1 can be further increased.
At this time, the temperature at which the head 1 is heated is not particularly limited as long as it is higher than room temperature and lower than the heat-resistant temperature of the head 1, but is preferably about 25 to 100 ° C., more preferably about 50 to 100 ° C. It is said. Heating at a temperature in such a range can reliably increase the bonding strength while reliably preventing the head 1 from being altered or deteriorated by heat.

The heating time is not particularly limited, but is preferably about 1 to 30 minutes.
In addition, when performing both said process [16A] and [16B], it is preferable to perform these simultaneously. That is, it is preferable to heat the head 1 while applying pressure. Thereby, the effect by pressurization and the effect by heating are synergistically exhibited, and the bonding strength of the head 1 can be particularly increased.
By performing the steps as described above, it is possible to easily further improve the bonding strength in the head 1.

<< Second Embodiment >>
Next, a second embodiment in which the droplet discharge head of the present invention is applied to an ink jet recording head will be described.
FIG. 12 is a partially enlarged view showing a state before energy application of the bonding film included in the second embodiment when the droplet discharge head of the present invention is applied to an ink jet recording head, and FIG. 13 is a droplet of the present invention. It is the elements on larger scale which show the state after the energy provision of the joining film with which 2nd Embodiment with which an ejection head is applied to an inkjet recording head is provided. In the following description, the upper side in FIGS. 12 and 13 is referred to as “upper” and the lower side is referred to as “lower”.

Hereinafter, the second embodiment of the ink jet recording head will be described, but the description will focus on differences from the ink jet recording head according to the first embodiment, and the description of the same matters will be omitted.
The ink jet recording head according to this embodiment is the same as that of the first embodiment except that the configuration of each bonding film is different.
In other words, the ink jet recording head according to the present embodiment includes the metal atoms, the oxygen atoms bonded to the metal atoms, and the metal atoms in the state where each of the bonding films 15, 25, 35, 45 a, 45 b is before energy application. And a leaving group 303 bonded to at least one of an atom and an oxygen atom. In other words, it can be said that each of the bonding films 15, 25, 35, 45a, and 45b before the application of energy is a film in which a leaving group 303 is introduced into a metal oxide film made of a metal oxide. it can.

  In each of the bonding films 15, 25, 35, 45 a, 45 b, when energy is applied, the leaving group 303 is released from at least one of a metal atom and an oxygen atom, and each bonding film 15, 25, 35, Active hands 304 are generated at least near the surface of 45a and 45b. As a result, the same adhesiveness as in the first embodiment appears on the surfaces of the bonding films 15, 25, 35, 45a, and 45b.

Hereinafter, the bonding films 15, 25, 35, 45a, and 45b according to the present embodiment will be described. Since these structures are common, the bonding film 15 will be described as a representative.
The bonding film 15 is composed of a metal atom and an oxygen atom bonded to the metal atom, that is, a bonding film 15 having a leaving group 303 bonded to a metal oxide, and thus is a strong film that is not easily deformed. . For this reason, the bonding film 15 itself has a high dimensional accuracy, and the head 1 finally obtained also has a high dimensional accuracy.

  Further, the bonding film 15 is a solid having no fluidity. For this reason, the thickness and shape of the adhesive layer (bonding film 15) hardly change as compared with a liquid or viscous liquid (semi-solid) adhesive having fluidity that has been conventionally used. Therefore, the dimensional accuracy of the head 1 obtained using the bonding film 15 is significantly higher than that of the conventional one. Furthermore, since the time required for curing the adhesive is not required, strong bonding can be achieved in a short time.

In the present invention, it is preferable that the bonding film 15 has conductivity. Thereby, in the head 1 to be described later, unintended charging can be suppressed or prevented. As a result, the ink ejection direction can be reliably controlled.
Also, if the bonding film 15 has conductivity, the resistivity of the bonding film 15, though slightly different depending on the composition of the material, but preferably not more than ^{1 × 10 -3 Ω · cm,} 1 × 10 - ^{4 Ω} · cm and more preferably not more than.

  The leaving group 303 only needs to be present at least near the surface 31 of the bonding film 15, may exist almost entirely on the bonding film 15, or is unevenly distributed near the surface 31 of the bonding film 15. May be. In addition, by adopting a configuration in which the leaving group 303 is unevenly distributed in the vicinity of the surface 31, the bonding film 15 can suitably exhibit a function as a metal oxide film. In other words, the bonding film 15 can be advantageously provided with a function as a metal oxide film having excellent characteristics such as conductivity and translucency in addition to the function responsible for bonding. In other words, it is possible to reliably prevent the leaving group 303 from impairing the properties of the bonding film 15 such as conductivity and translucency.

The metal atoms are selected so that the function as the bonding film 15 as described above is suitably exhibited.
Specifically, the metal atom is not particularly limited. For example, Li, Be, B, Na, Mg, Al, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn Ga, Rb, Sr, Y, Zr, Nb, Mo, Cd, In, Sn, Sb, Cs, Ba, La, Hf, Ta, W, Ti, Pb, and the like. Among these, it is preferable to use one or more of In (indium), Sn (tin), Zn (zinc), Ti (titanium), and Sb (antimony) in combination. By using the bonding film 15 containing these metal atoms, that is, a metal oxide containing these metal atoms introduced with a leaving group 303, the bonding film 15 has excellent conductivity and transparency. Will be demonstrated.

More specifically, examples of the metal oxide include indium tin oxide (ITO), indium zinc oxide (IZO), antimony tin oxide (ATO), fluorine-containing indium tin oxide (FTO), and zinc oxide. (ZnO) and titanium dioxide (TiO _2), and the like.
When indium tin oxide (ITO) is used as the metal oxide, the atomic ratio of indium to tin (indium / tin ratio) is preferably 99/1 to 80/20, and 97/3 More preferably, it is -85/15. Thereby, the effects as described above can be more remarkably exhibited.

The abundance ratio of metal atoms and oxygen atoms in the bonding film 15 is preferably about 3: 7 to 7: 3, and more preferably about 4: 6 to 6: 4. By setting the abundance ratio of metal atoms and oxygen atoms to be within the above range, the stability of the bonding film 15 increases, and the substrate 20 and the nozzle plate 10 can be bonded more firmly.
Further, as described above, the leaving group 303 behaves so as to generate an active hand in the bonding film 15 by leaving from at least one of a metal atom and an oxygen atom. Therefore, although the leaving group 303 is relatively easily and uniformly desorbed by being given energy, it is reliably bonded to the bonding film 15 so as not to be desorbed when no energy is given. Those are preferably selected.

  From this viewpoint, the leaving group 303 is preferably a hydrogen atom, a carbon atom, a nitrogen atom, a phosphorus atom, a sulfur atom, a halogen atom, or at least one of atomic groups composed of these atoms. It is done. Such a leaving group 303 is relatively excellent in bond / elimination selectivity by energy application. For this reason, such a leaving group 303 can sufficiently satisfy the above-described necessity, and the adhesiveness between the substrate 20 and the nozzle plate 10 can be enhanced.

Examples of the atomic group (group) composed of the above atoms include, for example, an alkyl group such as a methyl group and an ethyl group, an alkoxy group such as a methoxy group and an ethoxy group, a carboxyl group, an amino group, and a sulfonic acid. Groups and the like.
Among the atoms and atomic groups as described above, the leaving group 303 is particularly preferably a hydrogen atom. Since the leaving group 303 composed of hydrogen atoms has high chemical stability, the bonding film 15 having a hydrogen atom as the leaving group 303 has excellent weather resistance and chemical resistance.

Considering the above, the bonding film 15 includes indium tin oxide (ITO), indium zinc oxide (IZO), antimony tin oxide (ATO), fluorine-containing indium tin oxide (FTO), zinc oxide ( A material in which a hydrogen atom is introduced as a leaving group 303 into a metal oxide of ZnO) or titanium dioxide (TiO ₂ ) is preferably selected.
The bonding film 15 having such a configuration itself has excellent mechanical characteristics. In addition, it exhibits particularly excellent adhesion to many materials. Therefore, such a bonding film 15 adheres particularly firmly to the substrate 20 and also exhibits a particularly strong adherence to the nozzle plate 10. As a result, the substrate 20 and the nozzle plate 10 are firmly bonded. Can be joined.

The average thickness of the bonding film 15 is preferably about 1 to 1000 nm, and more preferably about 2 to 800 nm. By setting the average thickness of the bonding film 15 within the above range, it is possible to bond the substrate 20 and the nozzle plate 10 more firmly while preventing the dimensional accuracy of the head 1 from being significantly lowered.
That is, when the average thickness of the bonding film 15 is less than the lower limit value, there is a possibility that sufficient bonding strength cannot be obtained. On the other hand, when the average thickness of the bonding film 15 exceeds the upper limit, the dimensional accuracy of the head 1 may be significantly reduced.

  Furthermore, if the average thickness of the bonding film 15 is within the above range, a certain degree of shape followability is ensured for the bonding film 15. For this reason, for example, even when unevenness exists on the bonding surface of the substrate 20 (the surface on which the bonding film 15 is formed), the bonding film follows the unevenness shape depending on the height of the unevenness. 15 can be deposited. As a result, the bonding film 15 can absorb the unevenness and reduce the height of the unevenness generated on the surface. And when the board | substrate 20 and the nozzle plate 10 are bonded together, the adhesiveness with respect to the nozzle plate 10 of the joining film 15 can be improved.

In addition, the degree of the shape followability as described above becomes more prominent as the bonding film 15 is thicker. Therefore, in order to sufficiently ensure the shape following property, the thickness of the bonding film 15 should be as large as possible.
In the bonding film 15 described above, when the leaving group 303 is present in almost the entire bonding film 15, for example, A: physical atmosphere in an atmosphere containing an atomic component constituting the leaving group 303. It can be formed by depositing a metal oxide material containing metal atoms and oxygen atoms by a phase film formation method. When the leaving group 303 is unevenly distributed near the surface 31 of the bonding film 15, for example, after forming a metal oxide film containing B: metal atoms and the oxygen atoms, It can be formed by introducing a leaving group 303 into at least one of a metal atom and an oxygen atom contained in the vicinity of the surface.

Hereinafter, the case where the bonding film 15 is formed on the substrate 20 by using the methods A and B will be described in detail.
<A> In the method A, as described above, the bonding film 15 is formed of a metal atom and an oxygen by a physical vapor deposition method (PVD method) in an atmosphere containing an atomic component constituting the leaving group 303. It is formed by depositing a metal oxide material containing atoms. When the PVD method is used as described above, the leaving group 303 can be introduced into at least one of the metal atom and the oxygen atom relatively easily when the metal oxide material is made to fly toward the substrate 20. . For this reason, the leaving group 303 can be introduced over almost the entire bonding film 15.

  Furthermore, according to the PVD method, a dense and homogeneous bonding film 15 can be efficiently formed. Thereby, the bonding film 15 formed by the PVD method can be particularly strongly bonded to the nozzle plate 10. Furthermore, the bonding film 15 formed by the PVD method is maintained for a relatively long time in a state where energy is applied and activated. For this reason, the manufacturing process of the head 1 can be simplified and improved in efficiency.

  Further, examples of the PVD method include a vacuum deposition method, a sputtering method, an ion plating method, a laser ablation method, and the like. Among these, the sputtering method is preferably used. According to the sputtering method, metal oxide particles can be knocked out into an atmosphere containing an atomic component constituting the leaving group 303 without breaking a bond between a metal atom and an oxygen atom. Since the metal oxide particles can be brought into contact with a gas containing an atomic component constituting the leaving group 303, the leaving group to the metal oxide (metal atom or oxygen atom) can be contacted. 303 can be introduced more smoothly.

Hereinafter, as a method for forming the bonding film 15 by the PVD method, a case where the bonding film 15 is formed by a sputtering method (ion beam sputtering method) will be described as a representative.
First, prior to describing the method for forming the bonding film 15, the film forming apparatus 200 used when the bonding film 15 is formed on the substrate 20 by ion beam sputtering will be described.

FIG. 14 is a longitudinal sectional view schematically showing a film forming apparatus used for manufacturing a bonding film according to the present embodiment, and FIG. 15 is a schematic view showing a configuration of an ion source included in the film forming apparatus shown in FIG. is there. In the following description, the upper side in FIG. 14 is referred to as “upper” and the lower side is referred to as “lower”.
A film forming apparatus 200 shown in FIG. 14 is configured so that the bonding film 15 can be formed in a chamber (apparatus) by an ion beam sputtering method.

  Specifically, the film forming apparatus 200 includes a chamber (vacuum chamber) 211 and a substrate holder (film forming object holding unit) 212 that is installed in the chamber 211 and holds the substrate 20 (film forming object). An ion source (ion supply unit) 215 that is installed in the chamber 211 and irradiates the ion beam B toward the chamber 211, and a metal oxide that includes metal atoms and oxygen atoms by irradiation with the ion beam B (for example, , ITO) and a target holder (target holding portion) 217 for holding a target (metal oxide material) 216 for generating.

The chamber 211 has a gas supply means 260 for supplying a gas containing an atomic component constituting the leaving group 303 (for example, hydrogen gas) into the chamber 211, and the chamber 211 is evacuated to control the pressure. And an evacuation unit 230 for performing the operation.
In the present embodiment, the substrate holder 212 is attached to the ceiling portion of the chamber 211. The substrate holder 212 is rotatable. Accordingly, the bonding film 15 can be formed on the substrate 20 with a uniform and uniform thickness.

As shown in FIG. 15, the ion source (ion gun) 215 includes an ion generation chamber 256 in which an opening (irradiation port) 250 is formed, a filament 257 provided in the ion generation chamber 256, grids 253 and 254, And a magnet 255 installed outside the ion generation chamber 256.
Further, as shown in FIG. 14, a gas supply source 219 for supplying a gas (sputtering gas) is connected to the ion generation chamber 256.

In the ion source 215, when the filament 257 is energized and heated in a state where gas is supplied from the gas supply source 219 into the ion generation chamber 256, electrons are emitted from the filament 257, and the emitted electrons are generated by the magnetic field of the magnet 255. It moves and collides with gas molecules supplied into the ion generation chamber 256. Thereby, gas molecules are ionized. The ions I ⁺ of the gas are extracted from the ion generation chamber 256 and accelerated by a voltage gradient between the grid 253 and the grid 254 and are emitted (irradiated) from the ion source 215 as an ion beam B through the opening 250. Is done.

The ion beam B irradiated from the ion source 215 collides with the surface of the target 216, and particles (sputtered particles) are knocked out from the target 216. The target 216 is made of a metal oxide material as described above.
In the film forming apparatus 200, the ion source 215 is fixed (installed) on the side wall of the chamber 211 so that the opening 250 is located in the chamber 211. Note that the ion source 215 can be arranged at a position separated from the chamber 211 and connected to the chamber 211 via a connection portion. 200 can be reduced in size.

The ion source 215 is installed such that the opening 250 faces in a direction different from that of the substrate holder 212, in this embodiment, the bottom side of the chamber 211.
The number of ion sources 215 installed is not limited to one, and may be plural. By installing a plurality of ion sources 215, the deposition rate of the bonding film 15 can be further increased.

In addition, a first shutter 220 and a second shutter 221 that can cover the target holder 217 and the substrate holder 212 are disposed, respectively.
These shutters 220 and 221 are for preventing the target 216, the substrate 20 and the bonding film 15 from being exposed to an unnecessary atmosphere or the like, respectively.

The exhaust means 230 includes a pump 232, an exhaust line 231 that communicates the pump 232 and the chamber 211, and a valve 233 provided in the middle of the exhaust line 231. The pressure can be reduced.
Further, the gas supply means 260 includes a gas cylinder 264 that stores a gas (for example, hydrogen gas) that includes an atomic component constituting the leaving group 303, a gas supply line 261 that guides the gas from the gas cylinder 264 to the chamber 211, and a gas A pump 262 and a valve 263 provided in the middle of the supply line 261 are configured so that a gas containing an atomic component constituting the leaving group 303 can be supplied into the chamber 211.
Using the film forming apparatus 200 having the above configuration, the bonding film 15 is formed as follows.

Here, a method for forming the bonding film 15 on the substrate 20 will be described.
First, the substrate 20 is prepared, and the substrate 20 is carried into the chamber 211 of the film forming apparatus 200 and mounted (set) on the substrate holder 212.
Next, the exhaust means 230 is operated, that is, the valve 233 is opened while the pump 232 is operated, whereby the inside of the chamber 211 is decompressed. The degree of vacuum (degree of vacuum) is not particularly limited, but is preferably about 1 × 10 ⁻⁷ to 1 × 10 ⁻⁴ Torr, preferably about 1 × 10 ⁻⁶ to 1 × 10 ⁻⁵ Torr. Is more preferable.

Further, the gas supply means 260 is operated, that is, the valve 263 is opened while the pump 262 is operated, so that the gas containing the atomic components constituting the leaving group 303 is supplied into the chamber 211. Thereby, the inside of a chamber can be made into the atmosphere containing this gas (hydrogen gas atmosphere).
The flow rate of the gas containing the atomic component constituting the leaving group 303 is preferably about 1 to 100 ccm, and more preferably about 10 to 60 ccm. Thereby, the leaving group 303 can be reliably introduced into at least one of the metal atom and the oxygen atom.
Further, the temperature in the chamber 211 may be 25 ° C. or higher, but is preferably about 25 to 100 ° C. By setting within this range, the reaction between the metal atom or oxygen atom and the gas containing the atomic component is efficiently performed, and the gas containing the atomic component is reliably introduced into the metal atom and the oxygen atom. Can do.

Next, the second shutter 221 is opened, and the first shutter 220 is further opened.
In this state, a gas is introduced into the ion generation chamber 256 of the ion source 215, and the filament 257 is energized and heated. Thereby, electrons are emitted from the filament 257, and the emitted electrons collide with gas molecules, whereby the gas molecules are ionized.

The ions I ⁺ of the gas are accelerated by the grid 253 and the grid 254, emitted from the ion source 215, and collide with a target 216 made of a cathode material. Thereby, particles of metal oxide (for example, ITO) are knocked out from the target 216. At this time, since the inside of the chamber 211 is in an atmosphere containing a gas containing an atomic component constituting the leaving group 303 (for example, in a hydrogen gas atmosphere), the metal atoms contained in the particles knocked out into the chamber 211 And a leaving group 303 is introduced into the oxygen atom. Then, the bonding film 15 is formed by depositing the metal oxide introduced with the leaving group 303 on the substrate 20.

In the ion beam sputtering method described in this embodiment, in the ion generation chamber 256 of the ion source 215, a discharge is performed, the electron e ^- is occurs, the electron e ^- is shielded by the grid 253, Release into the chamber 211 is prevented.
Further, since the irradiation direction of the ion beam B (the opening 250 of the ion source 215) is directed to the target 216 (a direction different from the bottom side of the chamber 211), the ultraviolet rays generated in the ion generation chamber 256 are formed. Irradiation to the bonding film 15 is more reliably prevented, and it is possible to reliably prevent the leaving group 303 introduced during the formation of the bonding film 15 from being detached.
As described above, it is possible to form the bonding film 15 in which the leaving group 303 exists almost throughout.

  <B> On the other hand, in the method B, the bonding film 15 is formed of a metal oxide film containing metal atoms and oxygen atoms as described above, and then the metal contained in the vicinity of the surface of the metal oxide film. It is formed by introducing a leaving group 303 into at least one of an atom and an oxygen atom. According to such a method, it is possible to introduce the leaving group 303 in an unevenly distributed state near the surface of the metal oxide film in a relatively simple process, and to achieve both characteristics as a bonding film and a metal oxide film. An excellent bonding film 15 can be formed.

  Here, the metal oxide film may be formed by any method, for example, PVD method (physical vapor deposition method), CVD method (chemical vapor deposition method), plasma polymerization method, etc. The film can be formed by various vapor phase film forming methods, various liquid phase film forming methods, and the like, and it is particularly preferable to form the film by the PVD method. According to the PVD method, a dense and homogeneous metal oxide film can be efficiently formed.

  Moreover, examples of the PVD method include a vacuum deposition method, a sputtering method, an ion plating method, a laser ablation method, and the like. Among these, it is preferable to use a sputtering method. According to the sputtering method, the metal oxide particles can be struck out into the atmosphere and supplied onto the substrate 20 without breaking the bond between the metal atom and the oxygen atom. A physical film can be formed.

  Furthermore, as a method for introducing the leaving group 303 near the surface of the metal oxide film, various methods are used. For example, the metal oxide film is formed in an atmosphere containing an atomic component constituting the B1: leaving group 303. Examples of the method include heat treatment (annealing), B2: ion implantation, and the like. In particular, it is preferable to use the method B1. According to the method B1, the leaving group 303 can be selectively introduced near the surface of the metal oxide film relatively easily. Further, by appropriately setting the processing conditions such as the atmospheric temperature and the processing time when performing the heat treatment, the amount of the leaving group 303 to be introduced, and further the thickness of the metal oxide film into which the leaving group 303 is introduced. Can be accurately controlled.

Hereinafter, a metal oxide film is formed by a sputtering method (ion beam sputtering method), and then the obtained metal oxide film is subjected to heat treatment (annealing) in an atmosphere containing an atomic component constituting the leaving group 303. Thus, a case where the bonding film 15 is obtained will be described as a representative.
Even when the bonding film 15 is formed using the method B, a film forming apparatus similar to the film forming apparatus 200 used when forming the bonding film 15 using the method A is used. A description of the film forming apparatus is omitted.

[I] First, the substrate 20 is prepared. Then, the substrate 20 is carried into the chamber 211 of the film forming apparatus 200 and mounted (set) on the substrate holder 212.
[Ii] Next, the exhaust means 230 is operated, that is, the valve 233 is opened while the pump 232 is operated, so that the inside of the chamber 211 is decompressed. The degree of vacuum (degree of vacuum) is not particularly limited, but is preferably about 1 × 10 ⁻⁷ to 1 × 10 ⁻⁴ Torr, preferably about 1 × 10 ⁻⁶ to 1 × 10 ⁻⁵ Torr. Is more preferable.
At this time, the heating means is operated to heat the chamber 211. Although the temperature in the chamber 211 should just be 25 degreeC or more, it is preferable that it is about 25-100 degreeC. By setting within this range, a metal oxide film having a high film density can be formed.

[Iii] Next, the second shutter 221 is opened, and the first shutter 220 is further opened.
In this state, a gas is introduced into the ion generation chamber 256 of the ion source 215, and the filament 257 is energized and heated. Thereby, electrons are emitted from the filament 257, and the emitted electrons collide with gas molecules, whereby the gas molecules are ionized.

The ions I ⁺ of the gas are accelerated by the grid 253 and the grid 254, emitted from the ion source 215, and collide with a target 216 made of a cathode material. As a result, metal oxide (for example, ITO) particles are knocked out of the target 216 and deposited on the substrate 20 to form a metal oxide film containing metal atoms and oxygen atoms bonded to the metal atoms. Is done.

In the ion beam sputtering method described in this embodiment, in the ion generation chamber 256 of the ion source 215, a discharge is performed, the electron e ^- is occurs, the electron e ^- is shielded by the grid 253, Release into the chamber 211 is prevented.
Further, since the irradiation direction of the ion beam B (the opening 250 of the ion source 215) is directed to the target 216 (a direction different from the bottom side of the chamber 211), the ultraviolet rays generated in the ion generation chamber 256 are formed. Irradiation to the bonding film 15 is more reliably prevented, and it is possible to reliably prevent the leaving group 303 introduced during the formation of the bonding film 15 from being detached.

[Iv] Next, with the second shutter 221 open, the first shutter 220 is closed.
In this state, the heating means is operated to further heat the chamber 211. The temperature in the chamber 211 is set to a temperature at which the leaving group 303 is efficiently introduced onto the surface of the metal oxide film, and is preferably about 100 to 600 ° C., more preferably about 150 to 300 ° C. preferable. By setting within this range, the leaving group 303 can be efficiently introduced into the surface of the metal oxide film without altering or degrading the substrate 20 and the metal oxide film in the next step [v]. .

[V] Next, the gas supply means 260 is operated, that is, the valve 263 is opened in a state where the pump 262 is operated, so that the gas containing the atomic component constituting the leaving group 303 is supplied into the chamber 211. Thereby, the inside of the chamber 211 can be made into the atmosphere containing this gas (under hydrogen gas atmosphere).
As described above, in the state where the inside of the chamber 211 is heated in the step [iv], the inside of the chamber 211 includes an atmosphere containing a gas containing an atomic component constituting the leaving group 303 (for example, under a hydrogen gas atmosphere). Then, the leaving group 303 is introduced into at least one of metal atoms and oxygen atoms existing near the surface of the metal oxide film, and the bonding film 15 is formed.

The flow rate of the gas containing the atomic component constituting the leaving group 303 is preferably about 1 to 100 ccm, and more preferably about 10 to 60 ccm. Thereby, the leaving group 303 can be reliably introduced into at least one of the metal atom and the oxygen atom.
Note that, in the chamber 211, it is preferable to maintain the reduced pressure state adjusted by operating the exhaust unit 230 in the step [ii]. Thereby, the leaving group 303 can be introduced more smoothly into the vicinity of the surface of the metal oxide film. In addition, by reducing the pressure in the chamber 211 in this step while maintaining the reduced pressure state in the step [ii], it is possible to save the time for reducing the pressure again. There is also an advantage that it can be achieved.

The degree of vacuum (degree of vacuum) is not particularly limited, but is preferably about 1 × 10 ⁻⁷ to 1 × 10 ⁻⁴ Torr, preferably about 1 × 10 ⁻⁶ to 1 × 10 ⁻⁵ Torr. Is more preferable.
Moreover, it is preferable that the time which heat-processes is about 15 to 120 minutes, and it is more preferable that it is about 30 to 60 minutes.

Although depending on the type of leaving group 303 to be introduced and the like, the metal oxide film can be obtained by setting the conditions (temperature in the chamber 211, degree of vacuum, gas flow rate, treatment time) during the heat treatment within the above ranges. A leaving group 303 can be selectively introduced in the vicinity of the surface.
As described above, the bonding film 15 in which the leaving group 303 is unevenly distributed near the surface 31 can be formed.
In the ink jet recording head 1 according to the second embodiment as described above, the same operations and effects as in the first embodiment can be obtained.

<< Third Embodiment >>
Next, a third embodiment in which the droplet discharge head of the present invention is applied to an ink jet recording head will be described.
Hereinafter, the third embodiment of the ink jet recording head will be described. However, the difference from the ink jet recording head according to the first embodiment and the second embodiment will be mainly described. Description is omitted.

The ink jet recording head according to this embodiment is the same as that of the first embodiment except that the configuration of each bonding film is different.
That is, the ink jet recording head according to the present embodiment includes the leaving group 303 composed of a metal atom and an organic component in a state where each of the bonding films 15, 25, 35, 45 a, 45 b is before energy application. It is a waste.

  When each of the bonding films 15, 25, 35, 45 a, 45 b is given energy, the leaving group 303 is detached from each of the bonding films 15, 25, 35, 45 a, 45 b, and each bonding film 15, Active hands 304 are generated at least near the surfaces of 25, 35, 45a, and 45b. As a result, the same adhesiveness as in the second embodiment appears on the surfaces of the bonding films 15, 25, 35, 45a, and 45b.

Hereinafter, the bonding films 15, 25, 35, 45a, and 45b according to the present embodiment will be described. Since these structures are common, the bonding film 15 will be described as a representative.
The bonding film 15 is provided on the substrate 20 and includes a leaving group 303 composed of a metal atom and an organic component.
When energy is applied to such a bonding film 15, the bond of the leaving group 303 is broken and the bonding film 15 is desorbed from at least the vicinity of the surface 31, and as shown in FIG. 13, at least the surface of the bonding film 15 is removed. An active hand 304 is generated in the vicinity of 31. Thereby, adhesiveness is developed on the surface 31 of the bonding film 15. When such adhesiveness is developed, the substrate 20 provided with the bonding film 15 can be firmly and efficiently bonded to the nozzle plate 10 with high dimensional accuracy.

Further, since the bonding film 15 includes a metal atom and a leaving group 303 formed of an organic component, that is, an organic metal film, the bonding film 15 is a strong film that is not easily deformed. For this reason, the bonding film 15 itself has a high dimensional accuracy, and the head 1 finally obtained also has a high dimensional accuracy.
Such a bonding film 15 is a solid that does not have fluidity. For this reason, the thickness and shape of the adhesive layer (bonding film 15) hardly change as compared with a liquid or viscous liquid (semi-solid) adhesive having fluidity that has been conventionally used. Therefore, the dimensional accuracy of the head 1 obtained using such a bonding film 15 is significantly higher than that of the conventional one. Furthermore, since the time required for curing the adhesive is not required, strong bonding can be achieved in a short time.

In the present invention, it is preferable that the bonding film 15 has conductivity. Thereby, in the head 1 to be described later, unintended charging can be suppressed or prevented. As a result, the ink ejection direction can be reliably controlled.
The metal atom and the leaving group 303 are selected so that the function as the bonding film 15 as described above is suitably exhibited.

  Specifically, examples of the metal atom include Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Hf, Transition metal elements such as Ta, W, Re, Os, Ir, Pt, Au, various lanthanoid elements, various actinoid elements, Li, Be, Na, Mg, Al, K, Ca, Zn, Ga, Rb, Sr, Typical metal elements such as Cd, In, Sn, Sb, Cs, Ba, Tl, Pd, Bi, and Po are listed.

  Here, since the transition metal element is the only difference in the number of outermost electrons between the transition metal elements, the physical properties are similar. Transition metals generally have high hardness and melting point, and high electrical conductivity and thermal conductivity. For this reason, when a transition metal element is used as a metal atom, the adhesiveness expressed in the bonding film 15 can be further improved. In addition, the conductivity of the bonding film 15 can be further increased.

  Further, when one or more of Cu, Al, Zn and Fe are used as metal atoms in combination, the bonding film 15 exhibits excellent conductivity. In addition, when the bonding film 15 is formed by using a metal organic chemical vapor deposition method, which will be described later, a bonding film having a relatively easy and uniform film thickness using a metal complex containing these metals as a raw material. 15 can be formed.

  Further, as described above, the leaving group 303 behaves so as to generate an active hand in the bonding film 15 by detaching from the bonding film 15. Therefore, although the leaving group 303 is relatively easily and uniformly desorbed by being given energy, it is reliably bonded to the bonding film 15 so as not to be desorbed when no energy is given. Those are preferably selected.

  Specifically, as the leaving group 303, an atomic group containing a carbon atom as an essential component and containing at least one of a hydrogen atom, a nitrogen atom, a phosphorus atom, a sulfur atom and a halogen atom is suitably selected. Such a leaving group 303 is relatively excellent in bond / elimination selectivity by energy application. For this reason, such a leaving group 303 can sufficiently satisfy the above-described necessity, and the adhesiveness of the bonding film 15 can be further enhanced.

More specifically, examples of the atomic group (group) include an alkyl group such as a methyl group and an ethyl group, an alkoxy group such as a methoxy group and an ethoxy group, and a carboxyl group, and the end of the alkyl group is an isocyanate group. And those terminated with a group, an amino group, a sulfonic acid group, and the like.
Among the atomic groups as described above, the leaving group 303 is particularly preferably an alkyl group. Since the leaving group 303 composed of an alkyl group has high chemical stability, the bonding film 15 having an alkyl group as the leaving group 303 has excellent weather resistance and chemical resistance.

  In the bonding film 15 having such a configuration, the abundance ratio of metal atoms to oxygen atoms is preferably about 3: 7 to 7: 3, and more preferably about 4: 6 to 6: 4. By setting the abundance ratio of metal atoms and carbon atoms to be within the above range, the stability of the bonding film 15 increases, and the substrate 20 and the nozzle plate 10 can be bonded more firmly. Further, the bonding film 15 can exhibit excellent conductivity.

The average thickness of the bonding film 15 is preferably about 1 to 1000 nm, and more preferably about 50 to 800 nm. By setting the average thickness of the bonding film 15 within the above range, it is possible to bond the substrate 20 and the nozzle plate 10 more firmly while preventing the dimensional accuracy of the head 1 from being significantly lowered.
That is, when the average thickness of the bonding film 15 is less than the lower limit value, there is a possibility that sufficient bonding strength cannot be obtained. On the other hand, when the average thickness of the bonding film 15 exceeds the upper limit, the dimensional accuracy of the head 1 may be significantly reduced.

  Furthermore, if the average thickness of the bonding film 15 is within the above range, a certain degree of shape followability is ensured for the bonding film 15. For this reason, for example, even when unevenness exists on the bonding surface of the substrate 20 (the surface on which the bonding film 15 is formed), the bonding film follows the unevenness shape depending on the height of the unevenness. 15 can be deposited. As a result, the bonding film 15 can absorb the unevenness and reduce the height of the unevenness generated on the surface. And when the board | substrate 20 and the nozzle plate 10 are bonded together, the adhesiveness with respect to the nozzle plate 10 of the joining film 15 can be improved.

In addition, the degree of the shape followability as described above becomes more prominent as the bonding film 15 is thicker. Therefore, in order to sufficiently ensure the shape following property, the thickness of the bonding film 15 should be as large as possible.
The bonding film 15 as described above may be formed by any method. For example, IIa: an organic substance containing a leaving group (organic component) 303 on a metal film composed of a metal atom is used as a metal film. A method of forming the bonding film 15 by selectively applying (chemical modification) almost entirely or near the surface, IIb: an organic metal material having a metal atom and an organic substance containing a leaving group (organic component) 303 as a raw material As a method of forming the bonding film 15 using a metal organic chemical vapor deposition method (a method of laminating or forming a bonding layer made of a monoatomic layer), IIc: an organic substance containing a metal atom and a leaving group 303 Examples thereof include a method in which an organic metal material is dissolved in an appropriate solvent as a raw material and a bonding film is formed using a spin coating method or the like. Among these, it is preferable to form the bonding film 15 by the method IIb. According to such a method, the bonding film 15 having a uniform film thickness can be formed by a relatively simple process.

Hereinafter, by the method of IIb, that is, the method of forming the bonding film 15 using a metal organic chemical vapor deposition method using an organic metal material having a metal atom and an organic substance containing a leaving group (organic component) 303 as a raw material, A case where the bonding film 15 is obtained will be described as a representative.
First, before describing the method for forming the bonding film 15, the film forming apparatus 400 used for forming the bonding film 15 will be described.

FIG. 16 is a vertical cross-sectional view schematically showing a film forming apparatus used for manufacturing a bonding film in the present embodiment. In the following description, the upper side in FIG. 16 is referred to as “upper” and the lower side is referred to as “lower”.
A film forming apparatus 400 shown in FIG. 16 is configured so that the bonding film 15 can be formed in the chamber 411 by a metal organic chemical vapor deposition method (hereinafter sometimes abbreviated as “MOCVD method”). .

  Specifically, the film forming apparatus 400 includes a chamber (vacuum chamber) 411 and a substrate holder (film forming object holding unit) 412 that is installed in the chamber 411 and holds the substrate 20 (film forming object). , An organometallic material supply means 460 for supplying a vaporized or atomized organometallic material into the chamber 411, a gas supply means 470 for supplying a gas for making the inside of the chamber 411 under a low reducing atmosphere, and a chamber 411 It has an exhaust means 430 for controlling the pressure by exhausting the inside, and a heating means (not shown) for heating the substrate holder 412.

The substrate holder 412 is attached to the bottom of the chamber 411 in this embodiment. The substrate holder 412 can be rotated by the operation of a motor. Accordingly, the bonding film 15 can be formed on the substrate 20 with a uniform and uniform thickness.
Further, in the vicinity of the substrate holder 412, a shutter 421 that can cover them is provided. The shutter 421 is for preventing the substrate 20 and the bonding film 15 from being exposed to an unnecessary atmosphere or the like.

  The organometallic material supply unit 460 is connected to the chamber 411. The organometallic material supply means 460 includes a storage tank 462 that stores a solid organometallic material, a gas cylinder 465 that stores a carrier gas that feeds the vaporized or atomized organometallic material into the chamber 411, and a carrier gas. And a gas supply line 461 for introducing the vaporized or atomized organometallic material into the chamber 411, and a pump 464 and a valve 463 provided in the middle of the gas supply line 461. In the organometallic material supply means 460 having such a configuration, the storage tank 462 has a heating means, and the operation of the heating means can heat and vaporize the solid organometallic material. Therefore, when the pump 464 is operated with the valve 463 opened and the carrier gas is supplied from the gas cylinder 465 to the storage tank 462, the organometallic material vaporized or atomized together with the carrier gas passes through the supply line 461. Then, it is supplied into the chamber 411.

In addition, it does not specifically limit as carrier gas, For example, nitrogen gas, argon gas, helium gas, etc. are used suitably.
In this embodiment, the gas supply unit 470 is connected to the chamber 411. The gas supply means 470 includes a gas cylinder 475 for storing a gas for making the inside of the chamber 411 under a low reducing atmosphere, a gas supply line 471 for introducing the gas for making the low reducing atmosphere into the chamber 411, A pump 474 and a valve 473 provided in the middle of the gas supply line 471 are configured. In the gas supply means 470 having such a configuration, when the pump 474 is operated with the valve 473 opened, the gas for making the low reducing atmosphere is supplied from the gas cylinder 475 through the supply line 471 to the chamber 411. It is designed to be supplied inside. When the gas supply unit 470 is configured as described above, the inside of the chamber 411 can be surely set in a low reducing atmosphere with respect to the organometallic material. As a result, when forming the bonding film 15 by using the MOCVD method using the organic metal material as a raw material, at least a part of the organic component contained in the organic metal material is left as the leaving group 303 in the bonding film 15. Is deposited.

The gas for bringing the inside of the chamber 411 into a low reducing atmosphere is not particularly limited, and examples thereof include nitrogen gas and rare gases such as helium, argon, and xenon, nitrogen monoxide, and dinitrogen monoxide. These can be used alone or in combination of two or more.
In the case of using an organic metal material containing an oxygen atom in the molecular structure, such as 2,4-pentadionate-copper (II) or [Cu (hfac) (VTMS)] described later. In addition, it is preferable to add hydrogen gas to the gas for achieving a low reducing atmosphere. Thereby, the reducibility with respect to oxygen atoms can be improved, and the bonding film 15 can be formed without excessive oxygen atoms remaining in the bonding film 15. As a result, the bonding film 15 has a low abundance of metal oxide in the film, and exhibits excellent conductivity.

In addition, when at least one of the nitrogen gas, argon gas and helium gas described above is used as the carrier gas, the carrier gas can also exhibit a function as a gas for providing a low reducing atmosphere. it can.
The exhaust unit 430 includes a pump 432, an exhaust line 431 that communicates the pump 432 and the chamber 411, and a valve 433 provided in the middle of the exhaust line 431. The pressure can be reduced.
The bonding film 15 is formed on the substrate 20 by the MOCVD method using the film forming apparatus 400 configured as described above.

[I] First, the substrate 20 is prepared. Then, the substrate 20 is carried into the chamber 411 of the film forming apparatus 400 and mounted (set) on the substrate holder 412.
[Ii] Next, the exhaust unit 430 is operated, that is, the valve 433 is opened while the pump 432 is operated, so that the inside of the chamber 411 is decompressed. The degree of vacuum (degree of vacuum) is not particularly limited, but is preferably about 1 × 10 ⁻⁷ to 1 × 10 ⁻⁴ Torr, preferably about 1 × 10 ⁻⁶ to 1 × 10 ⁻⁵ Torr. Is more preferable.

  In addition, by operating the gas supply means 470, that is, by opening the valve 473 while the pump 474 is operated, the gas for making the low reducing atmosphere is supplied into the chamber 411, and the inside of the chamber 411 is supplied. Under a low reducing atmosphere. The flow rate of the gas by the gas supply means 470 is not particularly limited, but is preferably about 0.1 to 10 sccm, and more preferably about 0.5 to 5 sccm.

  Further, at this time, the heating means is operated to heat the substrate holder 412. The temperature of the substrate holder 412 varies slightly depending on the type of the bonding film 15 to be formed, that is, the type of raw material used when forming the bonding film 15, but is preferably about 80 to 600 ° C., and 100 to 450 ° C. More preferably, it is about 200-300 degreeC. By setting within this range, it is possible to form the bonding film 15 having excellent adhesiveness using an organometallic material described later.

[Iii] Next, the shutter 421 is opened.
Then, by operating the heating means provided in the storage tank 462 in which the solid organic metal material is stored, the pump 464 is operated in a state where the organic metal material is vaporized, and the vaporization is performed by opening the valve 463. Alternatively, the atomized organometallic material is introduced into the chamber together with the carrier gas.

As described above, when the vaporized or atomized organometallic material is supplied into the chamber 411 in a state where the substrate holder 412 is heated in the step [ii], the organometallic material is heated on the substrate 20. The bonding film 15 can be formed on the substrate 20 in a state where a part of the organic substance contained in the organometallic material remains.
That is, according to the MOCVD method, if a film containing metal atoms is formed so that a part of the organic substance contained in the organometallic material remains, a part of the organic substance exhibits a function as the leaving group 303. A film 15 can be formed on the substrate 20.

The organometallic material used in such MOCVD method is not particularly limited. For example, 2,4-pentadionate-copper (II), tris (8-quinolinolato) aluminum (Alq ₃ ), tris (4 - methyl-8-quinolinolato) aluminum (III) (Almq _3), (8- hydroxyquinoline) zinc _(Znq 2), copper phthalocyanine, Cu (hexafluoroacetylacetonate) (vinyltrimethylsilane) [Cu (hfac) (VTMS )], Cu (hexafluoroacetylacetonate) (2-methyl-1-hexen-3-ene) [Cu (hfac) (MHY)], Cu (perfluoroacetylacetonate) (vinyltrimethylsilane) [Cu ( pfac) (VTMS)], Cu (perfluoroacetylacetonate) 2-methyl-1-hexen-3-ene) [Cu (pfac) (MHY)] and other amides, acetylacetonates, alkoxys, silyls containing silicon, carboxyl groups containing various transition metal elements Examples thereof include metal complexes such as carbonyl compounds, alkyl metals such as trimethylgallium, trimethylaluminum, and diethylzinc, and derivatives thereof. Among these, the organometallic material is preferably a metal complex. By using the metal complex, the bonding film 15 can be reliably formed in a state where a part of the organic substance contained in the metal complex remains.

  Further, in this embodiment, the gas supply means 470 is operated so that the inside of the chamber 411 is in a low reducing atmosphere. By using such an atmosphere, a pure metal film is formed on the substrate 20. Without being formed, a film can be formed in a state in which a part of the organic substance contained in the organometallic material remains. That is, the bonding film 15 having excellent characteristics as both the bonding film and the metal film can be formed.

The flow rate of the vaporized or atomized organometallic material is preferably about 0.1 to 100 ccm, and more preferably about 0.5 to 60 ccm. Accordingly, the bonding film 15 can be formed with a uniform film thickness and with a part of the organic substance contained in the organometallic material remaining.
As described above, when the bonding film 15 is formed, the residue remaining in the film is used as the leaving group 303, so that it is not necessary to introduce a leaving group into the formed metal film or the like. The bonding film 15 can be formed by a relatively simple process.

Note that part of the organic substance remaining in the bonding film 15 formed using the organometallic material may function as the leaving group 303, or part of the organic substance may be the leaving group 303. It may function as.
As described above, the bonding film 15 can be formed.
In the ink jet recording head 1 according to the third embodiment as described above, the same operations and effects as those in the first embodiment and the second embodiment can be obtained.

As described above, the liquid droplet ejection head and the liquid droplet ejection apparatus of the present invention have been described based on the illustrated embodiments, but the present invention is not limited thereto.
For example, in the method of manufacturing the droplet discharge head of the present invention, the order of the steps may be changed without being limited to the configuration of the above embodiment. In addition, one or two or more arbitrary processes may be added, and unnecessary processes may be deleted.
Further, the above-described bonding method using the bonding film may be applied to bonding of members other than the above of the droplet discharge head.

Next, specific examples of the present invention will be described.
1. Production of inkjet recording head (Example 1)
<1> First, a stainless steel nozzle plate, a single crystal silicon plate base material, a polyphenylene sulfide resin (PPS) sealing sheet, a stainless steel diaphragm, and a lead zirconate sintered body A piezoelectric element composed of a laminate of the configured piezoelectric layer and an electrode film obtained by firing Ag paste, and a case head made of PPS were prepared.
Next, the base material was accommodated in the chamber of the plasma polymerization apparatus shown in FIG. 10, and surface treatment with oxygen plasma was performed.
Next, a plasma polymerization film (bonding film) having an average thickness of 200 nm was formed on the surface subjected to the surface treatment. The film forming conditions are as shown below.

<Film formation conditions>
-Source gas composition: Octamethyltrisiloxane-Source gas flow rate: 10 sccm
Carrier gas composition: Argon Carrier gas flow rate: 10 sccm
・ High frequency power output: 100W
・ High frequency output density: 25 W / cm ²
-Chamber pressure: 1 Pa (low vacuum)
・ Processing time: 15 minutes ・ Substrate temperature: 20 ° C.
The plasma polymerized film thus formed is composed of a polymer of octamethyltrisiloxane (raw material gas), and includes a Si skeleton including a siloxane bond and a random atomic structure, and an alkyl group (desorbed). Group).

Next, the obtained plasma polymerization film was irradiated with ultraviolet rays under the following conditions.
<Ultraviolet irradiation conditions>
-Atmospheric gas composition: Air (air)
・ Atmospheric gas temperature: 20 ℃
・ Atmospheric gas pressure: Atmospheric pressure (100 kPa)
UV wavelength: 172 nm
-UV irradiation time: 5 minutes On the other hand, the surface treatment by oxygen plasma was performed with respect to the single side | surface of the sealing sheet.
Next, 1 minute after irradiating the ultraviolet light, the base material and the sealing sheet are pasted so that the surface of the plasma polymerization film irradiated with the ultraviolet light and the surface subjected to the surface treatment of the sealing sheet are in contact with each other. Combined. Thereby, the joined body of the base material and the sealing sheet was obtained.

<2> Next, on the sealing sheet of the joined body of the base material and the sealing sheet, a plasma polymerization film was formed in the same manner as in the above step <1>.
Next, the obtained plasma polymerization film was irradiated with ultraviolet rays in the same manner as in the above step <1>. On the other hand, surface treatment with oxygen plasma was performed on one surface of the diaphragm.
And 1 minute after irradiating with ultraviolet rays, the joined body and the diaphragm were bonded so that the surface of the plasma polymerization film irradiated with ultraviolet rays and the surface subjected to the surface treatment of the diaphragm were in contact. Thereby, the base material, the sealing sheet, and the joined body of the diaphragm were obtained.

<3> Next, through holes were formed at positions where the discharge liquid supply chamber of the head was to be formed in the sealing sheet, the vibration plate, and the plasma polymerization film adjacent thereto. Further, a through hole was formed in an annular region surrounding the position where the piezoelectric element is assembled in the diaphragm. Each of these through holes was formed by an etching method.
<4> Next, on the vibration plate of the joined body in which the base material, the sealing sheet, and the vibration plate are joined, the step <1 is performed at a position where the piezoelectric element is assembled (a region inside the annular through hole). >, A plasma polymerized film was formed.

Next, the obtained plasma polymerization film was irradiated with ultraviolet rays in the same manner as in the above step <1>. On the other hand, surface treatment with oxygen plasma was performed on one surface of the piezoelectric element.
And 1 minute after irradiating the ultraviolet ray, the bonded body and the piezoelectric element were bonded so that the surface of the plasma polymerization film irradiated with the ultraviolet ray and the surface subjected to the surface treatment of the piezoelectric element were in contact with each other. As a result, a bonded body of the base material, the sealing sheet, the diaphragm, and the piezoelectric element was obtained.

<5> Next, a plasma polymerized film is formed at the position where the case head is assembled in the joined body in which the base material, the sealing sheet, the vibration plate, and the piezoelectric element are joined, in the same manner as in step <1>. Filmed.
Next, the obtained plasma polymerization film was irradiated with ultraviolet rays in the same manner as in the above step <1>. On the other hand, surface treatment with oxygen plasma was performed on the joint surface of the case head.
And 1 minute after irradiating with ultraviolet rays, the joined body and the case head were bonded so that the surface of the plasma polymerization film irradiated with the ultraviolet rays and the surface subjected to the surface treatment of the case head were in contact with each other. Thereby, a base material, a sealing sheet, a vibration plate, a piezoelectric element, and a case head joined body were obtained.
<6> Next, the obtained joined body was turned upside down, and the surface opposite to the surface to which the sealing sheet of the base material was joined was processed by an etching method. Then, a discharge liquid storage chamber and a discharge liquid supply chamber were formed in the base material, thereby obtaining a discharge liquid storage chamber forming substrate.

<7> Next, a plasma polymerization film was formed on the discharge liquid storage chamber forming substrate in the same manner as in the step <1>.
Next, the obtained plasma polymerization film was irradiated with ultraviolet rays in the same manner as in the above step <1>. On the other hand, the surface treatment by oxygen plasma was performed on the joint surface of the nozzle plate.
Then, one minute after the irradiation with the ultraviolet light, the discharge liquid storage chamber forming substrate and the nozzle plate are placed so that the surface irradiated with the ultraviolet light of the plasma polymerized film and the surface subjected to the surface treatment of the nozzle plate are in contact with each other. Pasted together. As a result, a joined body of a nozzle plate, a base material, a sealing sheet, a vibration plate, a piezoelectric element and a case head, that is, an ink jet recording head was obtained.
<8> Next, the obtained ink jet recording head was heated at 80 ° C. while being compressed at 3 MPa, and maintained for 15 minutes. As a result, the bonding strength of the ink jet recording head was improved.

(Example 2)
Joints other than the joint between the nozzle plate and the discharge liquid storage chamber forming substrate, that is, between the base material and the sealing sheet, between the sealing sheet and the diaphragm, and between the diaphragm and the piezoelectric element. An ink jet recording head was manufactured in the same manner as in Example 1 except that each joint between the diaphragm and the case head was bonded with an epoxy adhesive.

(Example 3)
An ink jet recording head was manufactured in the same manner as in Example 1 except that plasma polymerized films were formed on both sides of the bonding interface and the plasma polymerized films were bonded to each other as follows.
Specifically, first, in the same manner as in Example 1, a plasma polymerization film was formed on the base material.
Similarly, a plasma polymerization film was formed on the sealing sheet.

Next, the plasma polymerization film on the base material and the plasma polymerization film on the sealing sheet were each irradiated with ultraviolet rays.
Next, the base material and the sealing sheet were bonded so that each plasma polymerization film | membrane closely_contact | adheres. Thereby, the base material and the sealing sheet were joined.
Similarly, between the sealing sheet and the diaphragm, between the diaphragm and the piezoelectric element, between the diaphragm and the case head, between the discharge liquid storage chamber forming substrate and the nozzle plate, Each was joined.

Example 4
<1> First, a stainless steel nozzle plate, a single crystal silicon plate base material, a polyphenylene sulfide resin (PPS) sealing sheet, a stainless steel diaphragm, and a lead zirconate sintered body A piezoelectric element composed of a laminate of the configured piezoelectric layer and an electrode film obtained by firing Ag paste, and a case head made of PPS were prepared.

Next, the base material was housed in a chamber of a film forming apparatus shown in FIG. 14, and surface treatment with oxygen plasma was performed.
Next, a bonding film (average thickness: 100 nm) in which hydrogen atoms were introduced into ITO was formed on the surface subjected to the surface treatment by using an ion beam sputtering method. The film forming conditions are as shown below.

<Ion beam sputtering deposition conditions>
・ Target: ITO
・ Vacuum ultimate vacuum: 2 × 10 ⁻⁶ Torr
-Pressure in the chamber during film formation: 1 × 10 ⁻³ Torr
・ Hydrogen gas flow rate: 60 sccm
・ Temperature in chamber: 20 ℃
・ Ion beam acceleration voltage: 600V
Voltage applied to the grid on the ion generation chamber side: + 400V
Applied voltage to grid on chamber side: -200V
・ Ion beam current: 200 mA
-Gas species supplied to the ion generation chamber: Kr gas-Processing time: 20 minutes The bonding film formed in this manner is composed of ITO with hydrogen atoms introduced, and metal atoms (indium and Tin), an oxygen atom bonded to the metal atom, and a leaving group (hydrogen atom) bonded to at least one of the metal atom and the oxygen atom.

Next, the obtained bonding film was irradiated with ultraviolet rays under the following conditions.
<Ultraviolet irradiation conditions>
・ Atmosphere gas composition: Nitrogen gas ・ Atmosphere gas temperature: 20 ° C.
・ Atmospheric gas pressure: Atmospheric pressure (100 kPa)
UV wavelength: 172 nm
-UV irradiation time: 5 minutes On the other hand, the surface treatment by oxygen plasma was performed with respect to the single side | surface of the sealing sheet.
Next, one minute after irradiating the ultraviolet ray, the base material and the sealing sheet are bonded so that the surface of the bonding film irradiated with the ultraviolet ray comes into contact with the surface subjected to the surface treatment of the sealing sheet. It was. Thereby, the joined body of the base material and the sealing sheet was obtained.

<2> Next, a bonding film was formed on the sealing sheet of the joined body of the base material and the sealing sheet in the same manner as in the step <1>.
Next, the obtained bonding film was irradiated with ultraviolet rays in the same manner as in the above step <1>. On the other hand, surface treatment with oxygen plasma was performed on one surface of the diaphragm.
And 1 minute after irradiating the ultraviolet ray, the bonded body and the diaphragm were bonded so that the surface of the bonding film irradiated with the ultraviolet ray was in contact with the surface subjected to the surface treatment of the diaphragm. Thereby, the base material, the sealing sheet, and the joined body of the diaphragm were obtained.

<3> Next, through holes were formed at positions where the discharge liquid supply chamber of the head should be formed in the sealing sheet, the vibration plate, and the bonding film adjacent thereto. Further, a through hole was formed in an annular region surrounding the position where the piezoelectric element is assembled in the diaphragm. Each of these through holes was formed by an etching method.
<4> Next, on the vibration plate of the joined body in which the base material, the sealing sheet, and the vibration plate are joined, the step <1 is performed at a position where the piezoelectric element is assembled (a region inside the annular through hole). >, A bonding film was formed.

Next, the obtained bonding film was irradiated with ultraviolet rays in the same manner as in the above step <1>. On the other hand, surface treatment with oxygen plasma was performed on one surface of the piezoelectric element.
And 1 minute after irradiating the ultraviolet ray, the bonded body and the piezoelectric element were bonded so that the surface of the bonding film irradiated with the ultraviolet ray was in contact with the surface subjected to the surface treatment of the piezoelectric element. As a result, a bonded body of the base material, the sealing sheet, the diaphragm, and the piezoelectric element was obtained.

<5> Next, a bonding film is formed at the position where the case head is assembled in the bonded body in which the base material, the sealing sheet, the vibration plate, and the piezoelectric element are bonded in the same manner as in the above step <1>. did.
Next, the obtained bonding film was irradiated with ultraviolet rays in the same manner as in the above step <1>. On the other hand, surface treatment with oxygen plasma was performed on the joint surface of the case head.
And 1 minute after irradiating the ultraviolet light, the bonded body and the case head were bonded so that the surface of the bonding film irradiated with the ultraviolet light and the surface subjected to the surface treatment of the case head were in contact with each other. Thereby, a base material, a sealing sheet, a vibration plate, a piezoelectric element, and a case head joined body were obtained.
<6> Next, the obtained joined body was turned upside down, and the surface opposite to the surface to which the sealing sheet of the base material was joined was processed by an etching method. Then, a discharge liquid storage chamber and a discharge liquid supply chamber were formed in the base material, thereby obtaining a discharge liquid storage chamber forming substrate.

<7> Next, a bonding film was formed on the discharge liquid storage chamber forming substrate in the same manner as in the step <1>.
Next, the obtained bonding film was irradiated with ultraviolet rays in the same manner as in the above step <1>. On the other hand, the surface treatment by oxygen plasma was performed on the joint surface of the nozzle plate.
Then, 1 minute after irradiating the ultraviolet light, the discharge liquid storage chamber forming substrate and the nozzle plate are pasted so that the surface of the bonding film irradiated with the ultraviolet light and the surface subjected to the surface treatment of the nozzle plate are in contact with each other. Combined. As a result, a joined body of a nozzle plate, a base material, a sealing sheet, a vibration plate, a piezoelectric element and a case head, that is, an ink jet recording head was obtained.
<8> Next, the obtained ink jet recording head was heated at 80 ° C. while being compressed at 3 MPa, and maintained for 15 minutes. As a result, the bonding strength of the ink jet recording head was improved.

(Example 5)
An ink jet recording head was obtained in the same manner as in Example 4 except that the bonding film was formed as follows.
The base material was housed in the chamber of the film forming apparatus shown in FIG. 16, and surface treatment with oxygen plasma was performed.
Next, a raw material was 2,4-pentadionate-copper (II) on the surface subjected to the surface treatment, and a bonding film having an average thickness of 100 nm was formed by MOCVD. The film forming conditions are as shown below.

<Film formation conditions>
・ Atmosphere in the chamber: Nitrogen gas + Hydrogen gas ・ Organic metal material (raw material): 2,4-pentadionate-copper (II)
・ Flow rate of organometallic material: 1 sccm
・ Carrier gas: Nitrogen gas ・ Hydrogen gas flow rate: 0.2 sccm
・ Vacuum ultimate vacuum: 2 × 10 ⁻⁶ Torr
-Pressure in the chamber during film formation: 1 × 10 ⁻³ Torr
-Temperature of substrate holder: 275 ° C
・ Processing time: 10 minutes

The bonding film formed as described above contains a copper atom as a metal atom, and a part of an organic substance contained in 2,4-pentadionate-copper (II) remains as a leaving group. Is.
The ink jet recording head obtained as described above was heated at 120 ° C. while being compressed at 10 MPa and maintained for 15 minutes. As a result, the bonding strength of the ink jet recording head was improved.

(Comparative example)
All joints, that is, vibration between the nozzle plate and the discharge liquid storage chamber forming substrate, between the base material and the sealing sheet, between the sealing sheet and the diaphragm, between the diaphragm and the piezoelectric element, An ink jet recording head was manufactured in the same manner as in Example 1 except that each joint between the plate and the case head was joined with an epoxy adhesive.

2. 2. Evaluation of inkjet recording head 2.1 Evaluation of dimensional accuracy The dimensional accuracy of each of the inkjet recording heads obtained in the examples and comparative examples was measured.
As a result, each of the ink jet recording heads obtained in each example had higher dimensional accuracy than the ink jet recording head obtained in each comparative example.
In addition, when each ink jet recording head was incorporated into an ink jet printer and printed on printing paper, the printer incorporating the head obtained in each example printed compared to the printer incorporating the head obtained in each comparative example. It was recognized that the quality was excellent.

2.2 Evaluation of chemical resistance The ink jet recording heads obtained in each of the examples and comparative examples were filled with ink for an ink jet printer (manufactured by Epson) maintained at 80 ° C. and held for 3 weeks. Thereafter, the state of the ink jet recording head was evaluated.
As a result, in the ink jet recording head obtained in each example, almost no ink permeated into the joint. On the other hand, in the ink jet recording head obtained in the comparative example, the infiltration of the ink into the joint portion was recognized.

1 is an exploded perspective view showing a first embodiment in which a droplet discharge head of the present invention is applied to an ink jet recording head. FIG. 2 is a cross-sectional view of the ink jet recording head shown in FIG. 1. It is the schematic which shows embodiment of an inkjet printer provided with the inkjet recording head shown in FIG. It is the elements on larger scale which show the state before energy provision of the bonding film with which the ink jet recording head concerning a 1st embodiment is provided. It is the elements on larger scale which show the state after the energy provision of the joining film with which the inkjet recording head concerning 1st Embodiment is provided. It is a figure (longitudinal sectional drawing) for demonstrating the manufacturing method of an inkjet recording head. It is a figure (longitudinal sectional drawing) for demonstrating the manufacturing method of an inkjet recording head. It is a figure (longitudinal sectional drawing) for demonstrating the manufacturing method of an inkjet recording head. It is a figure (longitudinal sectional drawing) for demonstrating the manufacturing method of an inkjet recording head. It is a longitudinal cross-sectional view which shows typically the plasma polymerization apparatus used for preparation of the joining film with which the inkjet recording head concerning 1st Embodiment is provided. FIG. 6 is a cross-sectional view illustrating another configuration example of the ink jet recording head according to the first embodiment. FIG. 6 is a partial enlarged view showing a state before applying energy of a bonding film provided in the second embodiment when the droplet discharge head of the present invention is applied to an ink jet recording head. FIG. 6 is a partial enlarged view showing a state after energy application of a bonding film provided in the second embodiment when the droplet discharge head of the present invention is applied to an ink jet recording head. It is a longitudinal cross-sectional view which shows typically the film-forming apparatus used for preparation of the joining film with which the inkjet recording head concerning 2nd Embodiment is provided. It is a schematic diagram which shows the structure of the ion source with which the film-forming apparatus shown in FIG. 14 is provided. It is a longitudinal cross-sectional view which shows typically the film-forming apparatus used for preparation of the joining film with which the inkjet recording head concerning 3rd Embodiment is provided.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Inkjet recording head 10 ... Nozzle plate 11 ... Nozzle hole 15, 25, 35, 45a, 45b ... Bonding film 20 ... Discharge liquid storage chamber forming substrate 20 '... Base material 21 ... Discharge liquid Storage chamber 22 ... Discharge liquid supply chamber 23 ... Through hole 30 ... Sealing sheet 40 ... Vibrating plate 50 ... Piezoelectric element 51 ... Piezoelectric layer 52 ... Electrode film 53 ... Recess 60 ... Case head 61 …… Discharge liquid supply path 70 …… Reservoir 31 …… Surface 301 …… Si skeleton 302 …… Siloxane bond 303 …… Leaving group 304 …… Active hand 100 …… Plasma polymerization apparatus 101 …… Chamber 102 …… Ground Wire 103 ... Supply port 104 ... Exhaust port 130 ... First electrode 139 ... Electrostatic chuck 140 ... Second electrode 170 ... Pump 171 ... Pressure Force control mechanism 180 …… Power supply circuit 182 …… High frequency power supply 183 …… Matching box 184 …… Wiring 190 …… Gas supply part 191 …… Liquid storage part 192 …… Vaporizer 193 …… Gas cylinder 194 …… Piping 195 …… Diffusion plate 200 …… Film forming apparatus 211 …… Chamber 212 …… Substrate holder 215 …… Ion source 216 …… Target 217 …… Target holder 219 …… Gas supply source 220 …… First shutter 221 …… Second Shutter 230 ... Exhaust means 231 ... Exhaust line 232 ... Pump 233 ... Valve 250 ... Opening 253 ... Grid 254 ... Grid 255 ... Magnet 256 ... Ion generation chamber 257 ... Filament 260 ... Gas supply Means 261 ... Gas supply line 262 ... ... Pump 263 ... Valve 264 ... Gas cylinder 400 ... Deposition device 411 ... Chamber 412 ... Substrate holder 421 ... Shutter 430 ... Exhaust means 431 ... Exhaust line 432 ... Pump 433 ... Valve 460 ... Organometallic material supply means 461 ... Gas supply line 462 ... Storage tank 463 ... Valve 464 ... Pump 465 ... Gas cylinder 470 ... Gas supply means 471 ... Gas supply line 473 ... Valve 474 ... Pump 475 ... ... Gas cylinder 9 ... Inkjet printer 92 ... Main body 921 ... Tray 922 ... Discharge port 93 ... Head unit 931 ... Ink cartridge 932 ... Carriage 94 ... Printing device 941 ... Carriage motor 942 ... Reciprocation Mechanism 9 43 …… Carriage guide shaft 944 …… Timing belt 95 …… Feeding device 951 …… Feeding motor 952 …… Feeding roller 952a …… Driving roller 952b …… Driving roller 96 …… Control unit 97 …… Operation panel P ……Recording sheet

Claims (32)

And the base plate,
Provided on one surface of the pre-Symbol substrate, a nozzle plate having nozzle holes for ejecting ejection exudates as droplets,
Anda sealing plate provided on the other surface of the front Stories substrate,
A discharge liquid storage chamber for storing the discharge liquid is formed by the substrate, the nozzle plate, and the sealing plate,
The substrate and the nozzle plate are bonded via a bonding film,
The bonding film has been more formed in the plasma Polymerization includes an Si skeleton which have a siloxane (Si-O) bond, and the leaving group bonded to the Si skeleton, the Si-H bonds,
By the application of energy to the bonding film, wherein the leaving groups present on the front surface of the bonding film is desorbed from the Si skeleton, the adhesion was expressed in the table surface of the bonding film, the bonding film, A droplet discharge head, wherein the substrate and the nozzle plate are joined.   2. The droplet discharge head according to claim 1, wherein a sum of a content ratio of Si atoms and a content ratio of O atoms among atoms obtained by removing H atoms from all atoms constituting the bonding film is 10 to 90 atomic%. .   3. The droplet discharge head according to claim 1, wherein an abundance ratio of Si atoms to O atoms in the bonding film is 3: 7 to 7: 3.   The droplet discharge head according to claim 1, wherein the Si skeleton includes a siloxane bond and has a random atomic arrangement. The droplet discharge head according to claim 4 , wherein the crystallinity of the Si skeleton is 45% or less.   In the infrared light absorption spectrum of the bonding film including the Si—H bond, when the peak intensity attributed to the siloxane bond is 1, the peak intensity attributed to the Si—H bond is 0.001 to 0.2. The droplet discharge head according to claim 5.   The leaving group includes an H atom, a B atom, a C atom, an N atom, an O atom, a P atom, an S atom, and a halogen atom, or an atomic group arranged so that each of these atoms is bonded to the Si skeleton. The liquid droplet ejection head according to claim 1, comprising at least one selected from the group consisting of:   The liquid droplet ejection head according to claim 7, wherein the leaving group is an alkyl group.   In the infrared light absorption spectrum of the bonding film containing a methyl group as the leaving group, when the peak intensity attributed to the siloxane bond is 1, the peak intensity attributed to the methyl group is 0.05 to 0.45. The droplet discharge head according to claim 8.   The droplet discharge head according to claim 1, wherein the bonding film is made of polyorganosiloxane as a main material.   The liquid droplet ejection head according to claim 10, wherein the polyorganosiloxane is mainly composed of a polymer of octamethyltrisiloxane. 12. The droplet discharge head according to claim 1, wherein in the plasma polymerization method, a high-frequency power density when generating plasma is 0.01 to 100 W / cm ² .   The droplet discharge head according to claim 1, wherein an average thickness of the bonding film is 1 to 1000 nm.   The droplet discharge head according to claim 1, wherein the bonding film is a solid having no fluidity.   15. The liquid droplet ejection head according to claim 1, wherein the substrate is made of a silicon material or stainless steel as a main material.   The liquid droplet ejection head according to claim 1, wherein the nozzle plate is composed mainly of a silicon material or stainless steel.   17. The droplet discharge head according to claim 1, wherein a surface of the substrate that is in contact with the bonding film is previously subjected to a surface treatment for improving adhesion with the bonding film.   18. The droplet discharge head according to claim 1, wherein a surface of the nozzle plate that is in contact with the bonding film is subjected in advance to a surface treatment that improves adhesion with the bonding film.   19. The liquid droplet ejection head according to claim 17, wherein the surface treatment is a plasma treatment.   The liquid droplet ejection head according to claim 1, further comprising an intermediate layer between the substrate and the bonding film.   21. The droplet discharge head according to claim 1, further comprising an intermediate layer between the nozzle plate and the bonding film.   The liquid droplet ejection head according to claim 20 or 21, wherein the intermediate layer is composed mainly of an oxide-based material.   The energy is applied by at least one of a method of irradiating the bonding film with energy rays, a method of heating the bonding film, and a method of applying a compressive force to the bonding film. 23. The droplet discharge head according to any one of items 22 to 22.   24. The droplet discharge head according to claim 23, wherein the energy beam is an ultraviolet ray having a wavelength of 150 to 300 nm.   The droplet discharge head according to claim 23, wherein the heating temperature is 25 to 100 ° C.   24. The droplet discharge head according to claim 23, wherein the compressive force is 0.2 to 10 MPa. The substrate and the a sealing plate, the liquid droplet ejection head according to any one of claims 1 to 26 is bonded through a bonding film similar to the above bonding film. The sealing plate is composed of a laminate formed by laminating a plurality of layers,
The droplet discharge head according to any one of claims 1 to 27 , wherein at least one set of adjacent layers among the layers in the stacked body is bonded via a bonding film similar to the bonding film. . The liquid droplet ejection head is further provided on the opposite side of the sealing plate from the substrate, and has vibration means for vibrating the sealing plate,
The droplet discharge head according to any one of claims 1 to 28 , wherein the sealing plate and the vibration means are bonded via a bonding film similar to the bonding film. 30. The liquid droplet ejection head according to claim 29 , wherein the vibration means is composed of a piezoelectric element. The droplet discharge head further includes a case head provided on the opposite side of the sealing plate from the substrate,
The sealing plate and said casing head, the liquid droplet ejection head according to any one of the bonding film claims 1 are bonded through the same bonding film and 30. Droplet discharge apparatus comprising: a liquid droplet ejection head according to any one of claims 1 to 31.

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