JP2009028922A - Joining method, joint article, droplet ejection head and droplet ejection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining method capable of joining two adherends rigidly with high dimensional precision selectively on a part of region and efficiently at a low temperature to each other, to provide a joint article made by joining two adherends rigidly with high dimensional precision selectively on a part of region to each other, to provide a droplet ejection head having high reliability, which is provided with such a joint article, and to provide a droplet ejection device provided with such a droplet ejection head. <P>SOLUTION: The joining method comprises: an adherend preparation process of preparing a first base 21 and a second base 22 (a second adherend 42) and forming a plasma-polymerized film 3 on the first base 21 to make a first adherend 41; a stacking process of superposing the two adherends 41, 42 to each other to obtain a temporary joint article 5 so as to cause the plasma-polymerized film 3 to adhere to the second adherend 42; and an energy applying process of partially joining the temporary joint article 5 on a part of predetermined region 310 by applying energy selectively for the part of predetermined region 310 in the temporary joint article 5 to obtain the joint article 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a bonding method, a bonded body, a droplet discharge head, and a droplet discharge device.

When joining (adhering) two members (base materials), conventionally, a method of using an adhesive such as an epoxy adhesive, a urethane adhesive, or a silicone adhesive is often used.
The adhesive can exhibit adhesiveness regardless of the material of the member. For this reason, members composed of various materials can be bonded in various combinations.
For example, a droplet discharge head (inkjet recording head) provided in an inkjet printer is assembled by bonding parts made of different materials such as a resin material, a metal material, and a silicon material using an adhesive. ing.
When the members are bonded together using the adhesive as described above, a liquid or paste adhesive is applied to the bonding surface, and the members are bonded together via the applied adhesive. Thereafter, the adhesive is cured by the action of heat or light to bond the members together.

However, such an adhesive has the following problems.
・ Low bonding strength ・ Low dimensional accuracy ・ Long curing time, so it takes a long time to bond In addition, in many cases, it is necessary to use a primer to increase the bonding strength. Cost and complexity.

On the other hand, there is a solid bonding method as a bonding method that does not use an adhesive.
Solid bonding is a method of directly bonding members without an intermediate layer such as an adhesive (see, for example, Patent Document 1).
According to such solid bonding, since an intermediate layer such as an adhesive is not used, a bonded body with high dimensional accuracy can be obtained.

However, solid bonding has the following problems.
-There are restrictions on the materials of the members to be joined-In the joining process, heat treatment is performed at a high temperature (for example, about 700 to 800 ° C)-The atmosphere in the joining process is limited to a reduced-pressure atmosphere-Select some areas selectively Since it cannot be joined, a large stress is generated at the joining interface due to the difference in the coefficient of thermal expansion between the members, leading to peeling of the joined body. Depending on the material of the member used for joining, However, there is a need for a method for joining members firmly with high dimensional accuracy and efficiently at low temperatures.

JP-A-5-82404

  An object of the present invention is to provide a bonding method capable of bonding two adherends selectively in a partial area, with high dimensional accuracy, and efficiently at low temperature, and part of the two adherends. A bonded body that is selectively bonded in a high-precision region with high dimensional accuracy, a highly reliable droplet discharge head including the bonded body, and a droplet discharge apparatus including the droplet discharge head There is to do.

Such an object is achieved by the present invention described below.
The bonding method of the present invention includes an adherend preparation step of preparing a first adherend including a plasma polymerized film on a substrate, and a second adherend;
The first adherend and the second adherend are overlapped and temporarily bonded so that the plasma polymerized film of the first adherend and the second adherend are in close contact with each other. A laminating process for obtaining a body;
In the plasma polymerized film, energy is applied to a part of a predetermined region, thereby joining the plasma polymerized film and the second adherend in the predetermined region to obtain an joined body. It is characterized by having.

  Thereby, adhesiveness develops in the plasma polymerized film, and the two adherends can be selectively bonded to each other in a certain region, firmly with high dimensional accuracy, and efficiently at a low temperature. Further, since the plasma polymerized film and the second adherend are not joined in the temporarily joined state, the first adherend and the second adherend are shifted, and the relative relationship between them is determined. The position can be easily fine-tuned.

In the bonding method of the present invention, a first adherend comprising a substrate and a plasma polymerized film provided in a predetermined region on the substrate, and a second adherend are prepared. Kimono preparation process,
The first adherend and the second adherend are overlapped and temporarily bonded so that the plasma polymerized film of the first adherend and the second adherend are in close contact with each other. A laminating process for obtaining a body;
An energy applying step of joining the plasma polymerized film and the second adherend in the predetermined region by applying energy to the plasma polymerized film to obtain a joined body.

  Thereby, adhesiveness develops in the plasma polymerized film, and the two adherends can be selectively bonded to each other in a certain region, firmly with high dimensional accuracy, and efficiently at a low temperature. Further, since the plasma polymerized film and the second adherend are not joined in the temporarily joined state, the first adherend and the second adherend are shifted, and the relative relationship between them is determined. The position can be easily fine-tuned.

In the bonding method of the present invention, a hydroxyl group is present on the surface of the second adherend that is in close contact with the plasma polymerization film,
In the laminating step, the first adherend and the second adherend are overlapped so that the plasma polymerized film and the surface of the second adherend on which the hydroxyl group exists are in close contact with each other. It is preferable to match.
As a result, an attractive force based on a hydrogen bond is generated between the hydroxyl group present in the plasma polymerized film and the hydroxyl group present in the second adherend, and the gap between the plasma polymerized film and the second adherend is strong. To be joined.

In the bonding method of the present invention, the surface of the second adherend that is in close contact with the plasma polymerization film is covered with an oxide film,
In the laminating step, the first adherend and the second adherend are adhered so that the plasma polymerized film and the surface of the second adherend covered with the oxide film are in close contact with each other. Are preferably overlapped.
Since the hydroxyl group is bonded to the surface of the oxide film, the hydroxyl group and the hydroxyl group present in the plasma polymerized film attract each other by hydrogen bonding, and the plasma polymerized film and the second adherend are firmly bonded. Is done.

In the bonding method of the present invention, the second adherend is provided with a plasma polymerization film on a substrate,
In the laminating step, the plasma polymerized film of the first adherend and the plasma polymerized film of the second adherend are superposed so that they are in close contact with each other,
In the energy applying step, it is preferable to apply energy to at least a portion where the plasma polymerized film of the first adherend and the plasma polymerized film of the second adherend overlap each other.

  Thereby, the joint strength in the joined body can be improved. Moreover, even if the base material provided in the second adherend is a base material made of a material that has low adhesion to the plasma polymerized film and lowers the joint strength of the joined body, Since the plasma polymerized film is formed in advance, the first adherend and the second adherend can be bonded more firmly.

In the bonding method of the present invention, it is preferable that the second adherend includes a base material and a plasma polymerized film provided in a predetermined region on the base material.
Thereby, two adherends can be reliably joined in a partial region.
In the bonding method of the present invention, it is preferable that the plasma polymerized film of the first adherend and the plasma polymerized film of the second adherend are made of the same material.
Thereby, the affinity of the plasma polymerization film | membrane with which a 1st to-be-adhered body is equipped and the plasma polymerization film with which a 2nd to-be-adhered body is equipped improves, and these can be joined firmly.

In the bonding method of the present invention, the plasma polymerized film is preferably composed of polyorganosiloxane or organometallic polymer as a main material.
Thereby, a 1st to-be-adhered body and a 2nd to-be-adhered body can be joined more firmly. Further, polyorganosiloxane can easily control the adhesion of the plasma polymerized film. In addition, the organometallic polymer exhibits excellent conductivity when energy is imparted thereto, and a joined body applicable to wiring or the like can be obtained.

In the bonding method of the present invention, it is preferable that the polyorganosiloxane is mainly composed of a polymer of octamethyltrisiloxane.
Thereby, a plasma polymerization film having particularly excellent adhesiveness can be obtained. In addition, the raw material mainly composed of octamethyltrisiloxane is advantageous in that it is easy to handle because it is liquid at room temperature and has an appropriate viscosity.
In the bonding method of the present invention, it is preferable that the organometallic polymer is mainly composed of a polymer of trimethylgallium or trimethylaluminum.
Thereby, the first adherend and the second adherend are particularly strongly bonded, and energy is imparted to the plasma polymerized film, so that particularly high conductivity can be imparted.

In the bonding method of the present invention, the average thickness of the plasma polymerized film is preferably 1 to 1000 nm.
Thereby, the two adherends can be more firmly bonded to each other while preventing the dimensional accuracy of the bonded body from significantly decreasing. This also ensures a certain degree of shape following in the plasma polymerized film, so that the unevenness present on the bonding surface of the base material can be absorbed to reduce the height of the irregularities generated on the surface of the plasma polymerized film. it can. As a result, the joint strength of the joined body can be further improved.

In the bonding method of the present invention, the application of the energy in the energy application step is performed by at least one of a method of heating the temporary bonded body and a method of applying pressure to the temporary bonded body. Is preferred.
Thereby, energy can be imparted to the plasma polymerization film relatively easily and efficiently.

In the bonding method of the present invention, the heating temperature is preferably 25 to 100 ° C.
Thereby, the plasma polymerized film can be reliably activated and adhesiveness can be expressed in the plasma polymerized film while reliably preventing the base material from being altered or deteriorated by heat.
In the joining method of the present invention, the compressive force is preferably 0.2 to 10 MPa.
Thus, the plasma polymerized film can be reliably activated and the plasma polymerized film can exhibit adhesiveness by simply compressing the temporary joined body without causing damage to the substrate.

In the bonding method of the present invention, at least one of the base material provided in the first adherend and the base material provided in the second adherend has energy ray permeability,
The application of the energy in the energy application step is preferably performed by a method of irradiating the energy beam from the side of the base material having the permeability of the temporary joined body.
Thereby, a plasma polymerization film | membrane can be activated efficiently. In addition, large energy can be applied in a short time. Accordingly, since the molecular structure in the plasma polymerized film is not cut more than necessary, it can be avoided that the characteristics of the plasma polymerized film deteriorate.

In the bonding method of the present invention, at least one of the base material provided in the first adherend and the base material provided in the second adherend has translucency,
The energy application in the energy application step is preferably performed by a method of irradiating ultraviolet rays from the translucent substrate side of the temporary joined body.
Thereby, it is possible to activate a wide range of the plasma polymerized film without unevenness in a shorter time using simple equipment.

In the bonding method of the present invention, the wavelength of the ultraviolet light is preferably 150 to 300 nm.
Thereby, it is possible to activate the plasma polymerized film while preventing the characteristics of the plasma polymerized film from significantly deteriorating.
In the bonding method of the present invention, it is preferable that the energy beam irradiation is performed in an air atmosphere.
Thereby, it is not necessary to spend time and cost to control the atmosphere, and energy can be applied more easily.

In the joining method of this invention, it is preferable to have the process of heating the said joined body after the said energy provision process.
Thereby, dehydration condensation of the hydroxyl group further proceeds at the interface between the plasma polymerized film and the second adherend. As a result, the bonding strength in the bonded body can be further increased.
In the bonding method of the present invention, the heating temperature is preferably 25 to 100 ° C.
Accordingly, it is possible to reliably increase the bonding strength of the bonded body while reliably preventing the bonded body from being deteriorated and deteriorated by heat.

In the joining method of this invention, it is preferable to have the process of pressurizing the said joined body after the said energy provision process.
As a result, the plasma polymerization film and the second adherend are brought closer to each other, and dehydration condensation is promoted. As a result, the bonding strength in the bonded body can be further increased.
In the bonding method of the present invention, it is preferable that the pressure applied to the bonded body is 0.2 to 10 MPa.
Thereby, the joining strength of the joined body can be reliably increased without causing damage to the substrate.

In the bonding method of the present invention, the first adherend is previously subjected to a surface treatment for improving adhesion to the plasma polymerized film on the base material, and then the plasma is applied to the region subjected to the surface treatment. It is preferable to form a polymerized film.
Thereby, the joint surface of the base material is cleaned and activated, and the plasma polymerized film easily acts chemically on the joint surface. As a result, when a plasma polymerization film is formed on the bonding surface, the bonding strength between the bonding surface and the plasma polymerization film can be increased.

In the bonding method of the present invention, the surface treatment is preferably a plasma treatment.
Thereby, the joint surface of a base material can be cleaned and activated more. As a result, the bonding strength between the bonding surface and the plasma polymerization film can be particularly increased.
In the bonding method of the present invention, it is preferable that the base material provided in the first adherend and the base material provided in the second adherend have different rigidity.
Thereby, two adherends can be joined more firmly.

The joined body of the present invention is characterized in that two substrates are joined by the joining method of the present invention.
As a result, a bonded body is obtained in which the two adherends are selectively bonded to each other in a certain region and firmly with high dimensional accuracy.
In the joined body of the present invention, the joining strength between the two base materials is preferably 5 MPa or more.
Thereby, the joined body which can fully prevent peeling is obtained.
The droplet discharge head of the present invention is characterized by having the joined body of the present invention.
Thereby, a highly reliable droplet discharge head can be obtained.
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 bonding method, a bonded body, a droplet discharge head, and a droplet discharge device according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<Join method>
The bonding method of the present invention is a method in which two substrates (first substrate 21 and second substrate 22) are partially bonded in a partial region via the plasma polymerized film 3. That is, according to such a method, the two base materials 21 and 22 can be joined to each other in a partial region of the surfaces facing each other in a position-selective manner, with high dimensional accuracy, and at low temperature. Thereby, the joined body 1 is obtained.
Here, prior to describing the bonding method of the present invention, first, a plasma polymerization apparatus used to form the above-described plasma polymerization film will be described.

FIG. 1 is a longitudinal sectional view schematically showing a plasma polymerization apparatus used in the bonding method of the present invention. In the following description, the upper side in FIG. 1 is referred to as “upper” and the lower side is referred to as “lower”.
A plasma polymerization apparatus 100 shown in FIG. 1 includes a chamber 101, a first electrode 130 that supports a first substrate 21, a second electrode 140, and a power source that applies a high-frequency voltage between the electrodes 130 and 140. A circuit 180, 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. 1 has a substantially cylindrical chamber body whose axis is arranged in 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 first base material 21.
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 first substrate 21.
As shown in FIG. 1, the electrostatic chuck 139 can support the first base material 21 along the vertical direction. Further, even if the first base material 21 has a slight warp, the first base material 21 can be subjected to a plasma treatment 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 first base material 21 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. 1 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 first substrate 21.
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. In addition, contamination and oxidation of the first base material 21 due to contact with the air atmosphere can be prevented, and reaction products resulting from 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.

<< First Embodiment >>
Next, the first embodiment of the bonding method of the present invention will be described by taking the case of using the plasma polymerization apparatus 100 as an example.
2 and 3 are views (longitudinal sectional views) for explaining the first embodiment of the joining method of the present invention. In the following description, the upper side in FIGS. 2 and 3 is referred to as “upper” and the lower side is referred to as “lower”.

  The joining method according to the present embodiment prepares the first base material 21 and the second base material 22 (second adherend 42), and on the joining surface 23 of the first base material 21, The plasma polymerized film 3 is formed, and the adherend preparing step for producing the first adherend 41 is overlapped so that the plasma polymerized film 3 and the second adherend 42 are in close contact with each other, It has the lamination process which obtains the temporary joining body 5, and the energy provision process which selectively gives energy with respect to at least one part predetermined | prescribed area | region among the temporary joining bodies 5, and obtains a joining body. Hereinafter, each process will be described sequentially.

[1] First, a first base material 21 and a second base material 22 are prepared. In FIGS. 2A to 2C, one of the two base materials 21 and 22 is omitted.
The constituent materials of the first base material 21 and the second base material 22 are not particularly limited, but polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), and the like. Polyolefin, 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 copolymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrene copolymer, polyoxymethylene, polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer Polyester such as coalescence (EVOH), polyethylene terephthalate (PET), polyethylene naphthalate, polybutylene terephthalate (PBT), polycyclohexane terephthalate (PCT), polyether, polyether ketone (PEK), polyether ether ketone (PEEK), Polyetherimide, polyacetal (POM), polyphenylene oxide, modified polyphenylene oxide, polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, aromatic polyester (liquid crystal polymer), polytetrafluoroethylene, polyvinylidene fluoride, and other fluororesins , Styrene, polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide, polybutadiene, Various thermoplastic elastomers such as Lance polyisoprene, fluororubber, chlorinated polyethylene, epoxy resin, phenol resin, urea resin, melamine resin, aramid resin, unsaturated polyester, silicone resin, polyurethane, etc. Copolymers, blends, resin materials such as polymer alloys, Fe, Ni, Co, Cr, Mn, Zn, Pt, Au, Ag, Cu, Pd, Al, W, Ti, Ta, V, Mo , Nb, Zr, Pr, Nd, Sm, or alloys containing these metals, carbon steel, stainless steel, indium tin oxide (ITO), fluorine doped tin oxide (FTO), gallium arsenide (GaAs), Metallic materials such as gallium phosphide (GaP), silicon such as single crystal silicon, polycrystalline silicon, and amorphous silicon Con materials, glass materials such as silicate glass (quartz glass), alkali silicate glass, soda lime glass, potassium lime glass, lead (alkali) glass, barium glass, borosilicate glass, alumina, zirconia, ferrite, Ceramic materials such as silicon nitride, aluminum nitride, boron nitride, titanium nitride, silicon carbide, boron carbide, titanium carbide, tungsten carbide, carbon-based materials such as graphite, or one or more of these materials And composite materials in which are combined.

In addition, the first base material 21 and the second base material 22 are each subjected to plating treatment such as Ni plating, passivation treatment such as chromate treatment, nitriding treatment, or the like on the surface thereof. There may be.
The constituent material of the first base material 21 and the constituent material of the second base material 22 may be the same or different.

Moreover, it is preferable that the thermal expansion coefficient of the 1st base material 21 and the thermal expansion coefficient of the 2nd base material 22 are substantially equal. If these thermal expansion coefficients are substantially equal, when the first base material 21 and the second base material 22 are joined, it is difficult for stress associated with thermal expansion to occur at the joint interface. As a result, peeling can be reliably prevented in the finally obtained bonded body 1.
In addition, although it explains in full detail later, even when the thermal expansion coefficient of the 1st base material 21 and the thermal expansion coefficient of the 2nd base material 22 mutually differ, in the process mentioned later, the 1st base material 21 and 2nd By optimizing the conditions for joining the base material 22, these can be firmly joined with high dimensional accuracy.

Moreover, it is preferable that the two base materials 21 and 22 have mutually different rigidity. Thereby, the two base materials 21 and 22 can be joined more firmly.
Moreover, it is preferable that at least one constituent material of the two base materials 21 and 22 is a resin material. The resin material can relieve stress (for example, stress accompanying thermal expansion) generated at the bonding interface when the two base materials 21 and 22 are bonded due to its flexibility. For this reason, it becomes difficult to destroy the bonding interface, and as a result, the bonded body 1 having high bonding strength can be obtained.
Moreover, the shape of each base material 21 and 22 should just be a shape which has the surface which supports the plasma polymerization film | membrane 3, respectively, For example, it is set as plate shape (layer shape), lump shape (block shape), rod shape, etc. The

In the present embodiment, as shown in FIG. 2A, each of the base materials 21 and 22 has a plate shape. Thereby, each base material 21 and 22 becomes easy to bend, and when the two base materials 21 and 22 are overlap | superposed, it can fully deform | transform along a shape mutually. For this reason, the adhesiveness when the two base materials 21 and 22 are overlapped is increased, and the bonding strength in the finally obtained bonded body 1 is increased.
In addition, it is expected that the base material 21 and 22 are bent to alleviate the stress generated at the joint interface to some extent.
In this case, the average thickness of each of the base materials 21 and 22 is not particularly limited, but is preferably about 0.01 to 10 mm, and more preferably about 0.1 to 3 mm.

  Next, a surface treatment for improving the adhesion with the plasma polymerization film 3 is performed on the bonding surface 23 of the first base material 21 as necessary. Thereby, the bonding surface 23 is cleaned and activated, and the plasma polymerization film 3 easily acts on the bonding surface 23 chemically. As a result, when the plasma polymerization film 3 is formed on the bonding surface 23 in a process described later, the bonding strength between the bonding surface 23 and the plasma polymerization film 3 can be increased.

This surface treatment is not particularly limited, for example, physical treatment such as sputtering treatment, blast treatment, plasma treatment using oxygen plasma, nitrogen plasma, corona discharge treatment, etching treatment, electron beam irradiation treatment, Examples thereof include a chemical surface treatment such as ultraviolet irradiation treatment, ozone exposure treatment, or a combination thereof.
In addition, when the 1st base material 21 which performs surface treatment is comprised with the resin material (polymer material), especially a corona discharge process, a nitrogen plasma process, etc. are used suitably.

In addition, the surface 23 can be cleaned and activated more particularly by performing plasma treatment. As a result, the bonding strength between the bonding surface 23 and the plasma polymerization film 3 can be particularly increased.
In addition, depending on the constituent material of the first base material 21, the bonding strength with the plasma polymerization film 3 is sufficiently high without performing the surface treatment as described above. Examples of the constituent material of the first base material 21 that can obtain such an effect include materials 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 first base material 21 made of such a material is covered with an oxide film, and a hydroxyl group is bonded to the surface of the oxide film. Therefore, by using the first base material 21 covered with such an oxide film, the bonding surface 23 of the first base material 21 and the plasma polymerization film 3 can be obtained without performing the surface treatment as described above. It is possible to increase the bonding strength.
In this case, the entire first base material 21 may not be made of the material as described above, and at least the vicinity of the bonding surface 23 may be made of the material as described above.

Instead of the surface treatment, an intermediate layer may be formed in advance on the bonding surface 23 of the first base material 21.
This intermediate layer may have any function, and for example, a layer having a function of improving adhesion to the plasma polymerized film 3, a cushioning function (buffer function), a function of reducing stress concentration, and the like are preferable. The first substrate 21 and the plasma polymerized film 3 are bonded through such an intermediate layer, and the bonded body 1 with high reliability 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 materials such as graphite and diamond-like carbon, silane coupling agents, thiol compounds, metal alkoxides, self-assembled film materials such as metal-halogen compounds, resin adhesives, resin films, resin coating materials, Various rubber materials, resin materials such as various elastomers, and the like can be used, and one or more of these can be used in combination.
Further, among the intermediate layers formed of these materials, the intermediate layer formed of the oxide-based material particularly increases the bonding strength between the first base material 21 and the plasma polymerized film 3. Can do.

On the other hand, the plasma polymerized film 3 and the bonding surface 24 of the second base material 22 (the surface that is in close contact with the plasma polymerized film 3 in the process described later) may be preliminarily attached to the second base material 22 as necessary. A surface treatment may be applied to improve the adhesion. Thereby, the bonding surface 24 is cleaned and activated. As a result, when the bonding surface 24 and the plasma polymerized film 3 are brought into close contact with each other in the process described later, the bonding strength between the bonding surface 24 and the plasma polymerized film 3 can be increased.
Although it does not specifically limit as this surface treatment, The process similar to the surface treatment with respect to the joint surface 23 of the above-mentioned 1st base material 21 can be used.

  Similarly to the case of the first base material 21, depending on the constituent material of the second base material 22, the adhesion to the plasma polymerized film 3 is sufficiently high even without performing the surface treatment as described above. There is something to be. Examples of the constituent material of the second base material 22 that can obtain such an effect include materials mainly composed of various metal-based materials, various silicon-based materials, various glass-based materials and the like as described above.

That is, the surface of the second substrate 22 made of such a material is covered with an oxide film, and hydroxyl groups are bonded to the surface of the oxide film. Therefore, by using the second base material 22 covered with such an oxide film, the bonding surface 24 of the second base material 22 and the plasma polymerization film 3 can be obtained without performing the surface treatment as described above. It is possible to increase the bonding strength.
In this case, the entire second base material 22 may not be made of the material as described above, and at least the vicinity of the bonding surface 24 may be made of the material as described above.

Further, when the bonding surface 24 of the second base material 22 has the following groups or substances, the bonding surface 24 of the second base material 22 and the plasma polymerization can be performed without performing the surface treatment as described above. The bonding strength with the film 3 can be sufficiently increased.
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. At least one group or substance selected from the group consisting of saturated bonds, halogens such as F, Cl, Br and I, and peroxides, or unterminated bonds formed by elimination of these groups ( (Unbonded hand, dangling bond).

Moreover, the second surface capable of being strongly bonded to the plasma polymerized film 3 by appropriately selecting and performing various surface treatments as described above on the bonding surface 24 so as to have such groups and substances The base material 22 is obtained.
Among these, it is preferable that the bonding surface 24 of the second base material 22 has a hydroxyl group. A large attractive force based on the hydrogen bond is generated between the bonding surface 24 and the plasma polymerization film 3 where the hydroxyl group is exposed. Thereby, the 1st to-be-adhered body 41 and the 2nd to-be-adhered body 42 can be joined especially firmly.

Further, instead of the surface treatment, an intermediate layer may be formed in advance on the bonding surface 24 of the second base material 22.
This intermediate layer may have any function. For example, as in the case of the first base material 21, the function of improving the adhesion with the plasma polymerization film 3, the cushioning property (buffer function), What has the function etc. which relieve stress concentration is preferable. By bonding the second base material 22 and the plasma polymerized film 3 through such an intermediate layer, a highly reliable bonded body 1 can be obtained.
As the constituent material of the intermediate layer, for example, the same material as the constituent material of the intermediate layer formed on the bonding surface 23 of the first base member 21 can be used.
The surface treatment and the formation of the intermediate layer as described above may be performed as necessary, and can be omitted when a high bonding strength is not particularly required.

  In addition, depending on the constituent material of the second base material 22, the surface treatment described above is performed on the joint surface 24 of the second base material 22 by applying energy to the temporary joined body 5 in an energy application process described later. It can be expected to bring about the same action and effect as the action. In this case, a sufficiently high bonding strength can be obtained even if the surface treatment and the formation of the intermediate layer are omitted.

[2] Next, as shown in FIGS. 2A to 2C, the plasma polymerized film 3 is formed on the bonding surface 23 of the first base material 21 (adherent preparation step).
The plasma polymerized film 3 can be obtained by polymerizing molecules in the source gas by supplying a mixed gas of the source gas and the carrier gas in a strong electric field.
Specifically, first, the first base material 21 is accommodated in the chamber 101 to be in a sealed state, and then the inside of the chamber 101 is brought into a reduced pressure state by the operation of the exhaust pump 170.

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 into the chamber 101 (see FIG. 2A).
The ratio (mixing ratio) of the raw material gas in the mixed gas is slightly different depending on the kind of the raw material gas and the carrier gas, the target film forming speed, and the like. For example, the proportion of the raw material gas in the mixed gas is 20 to 70%. It is preferable to set it to a degree, and it is more preferable to set it to about 30 to 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. The molecules in the source gas are polymerized by the energy of the plasma, and the polymer is adhered and deposited on the first substrate 21 as shown in FIG. Thereby, the plasma polymerization film | membrane 3 is formed on the 1st base material 21 (refer FIG.2 (c)).

  Examples of the source gas include methylsiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, decamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, organosiloxane such as methylphenylsiloxane, trimethylgallium, triethylgallium, trimethylaluminum, Examples thereof include organometallic compounds such as triethylaluminum, triisobutylaluminum, trimethylindium, triethylindium, trimethylzinc, and triethylzinc, various hydrocarbon compounds, and various fluorine compounds.

The plasma polymerized film 3 obtained by using such a raw material gas is obtained by polymerizing these raw materials (polymer), that is, polyorganosiloxane, organometallic polymer, hydrocarbon polymer, fluorine polymer, and the like. Will be composed.
Among these, the plasma polymerized film 3 is preferably composed mainly of polyorganosiloxane or organometallic polymer. Thereby, the plasma polymerization film | membrane 3 can join the 1st base material 21 and the 2nd base material 22 more firmly.
Of these, polyorganosiloxane usually exhibits water repellency (non-adhesiveness), but when given energy, it can easily desorb organic groups, changes to hydrophilicity, and adheres. Sex is expressed.

That is, even when the plasma polymerized film 3 composed of polyorganosiloxane exhibiting water repellency is brought into contact with the second base material 22 in the process described later, adhesion is inhibited by the organic group on the surface of the plasma polymerized film 3. It will be extremely difficult to bond. On the other hand, when the plasma polymerized film 3 made of polyorganosiloxane having hydrophilicity is brought into contact with the second base material 22, both can be bonded. That is, the advantage that the water repellency and the hydrophilicity can be easily controlled leads to the advantage that the adhesiveness can be easily controlled.
Therefore, the plasma polymerized film 3 exhibits adhesion relatively easily and uniformly by applying energy, but exhibits non-adhesiveness and prevents unintended adhesion when energy is not applied. It will be a thing.

In addition, since polyorganosiloxane is relatively flexible, for example, even when the constituent materials of the first base material 21 and the second base material 22 are different from each other, the space between the base materials 21 and 22 is different. It is possible to relieve the stress accompanying thermal expansion that occurs in Thereby, peeling can be reliably prevented in the bonded body 1 finally obtained.
Furthermore, since polyorganosiloxane is excellent in chemical resistance, it can be effectively used for joining members that are exposed to chemicals for a long time. Specifically, for example, when manufacturing a droplet discharge head of an industrial inkjet printer in which an organic ink that easily erodes a resin material is used, by using the plasma polymerized film 3 mainly composed of polyorganosiloxane. , Its durability can be improved.

  Such a polyorganosiloxane has a random atomic structure including a siloxane (Si—O) bond. By having such a structure, the polyorganosiloxane becomes a strong film that is hardly deformed. For this reason, the plasma polymerized film 3 exhibits particularly excellent adhesiveness, and the plasma polymerized film 3 itself has high dimensional accuracy. For this reason, finally, the bonded body 1 having excellent bonding strength and high dimensional accuracy is obtained.

  The crystallinity of such a polyorganosiloxane is not particularly limited, but is preferably 45% or less, and more preferably 40% or less. As a result, the polyorganosiloxane contains a sufficiently random atomic structure. For this reason, the characteristic which the polyorganosiloxane mentioned above becomes obvious, and the dimensional accuracy and adhesiveness of the plasma polymerization film 3 become more excellent.

Further, when the plasma polymerized film 3 is composed of polyorganosiloxane, the sum of the Si atom content and the O atom content of all atoms constituting the plasma polymerized film 3 excluding H atoms. However, it is preferable that it is about 10-90 atomic%, and it is more preferable that it is about 20-80 atomic%. If Si atoms and O atoms are included in the above-mentioned range, the plasma polymerized film 3 forms a strong network of Si atoms and O atoms, and the plasma polymerized film 3 itself is strong. Become. The plasma polymerized film 3 exhibits particularly high bonding strength with respect to the first base material 21 and the second base material 22.
The abundance ratio of Si atoms and O atoms in the plasma polymerized film 3 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 plasma polymerized film 3 is increased, and the adherends 41 and 42 can be bonded more firmly. .

  Further, among polyorganosiloxanes, those mainly composed of a polymer of octamethyltrisiloxane are preferred. A plasma polymerized film containing a polymer of octamethyltrisiloxane as a main component is particularly excellent in adhesiveness, and is particularly preferably used in the bonding method 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 an advantage that it is easy to handle.

On the other hand, the organometallic polymer exhibits excellent electrical conductivity when applied with energy, and can more firmly bond the two base materials 21 and 22 together. Therefore, the plasma polymerized film 3 made of an organometallic polymer constitutes a bonded body 1 that can be used as a highly reliable wiring that can surely prevent peeling and the like through an energy application step described later. It will be possible.
Further, among the organometallic polymers, those mainly composed of a polymer of trimethylgallium or trimethylaluminum are preferable. Among these organometallic polymers, these components can particularly strongly bond the two base materials 21 and 22 and can impart particularly high conductivity to the plasma polymerized film by being imparted with energy.

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 to 10 / cm ^2, more preferably about 0.1 to 1 W / cm ^2.
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.
Moreover, it is preferable that the temperature of the 1st base material 21 is 25 degreeC or more, and it is more preferable that it is about 25-100 degreeC.
By appropriately setting such conditions, the dense plasma polymerized film 3 can be formed without unevenness.

In the present embodiment, the procedure for forming the plasma polymerization film 3 on the first base material 21 using the plasma polymerization apparatus is described. However, the first base material 21 provided with the plasma polymerization film 3 is described. (First adherend 41) may be prepared in advance, and the adherend may be used.
Moreover, it is preferable that the average thickness of the plasma polymerization film | membrane 3 is about 1-1000 nm, and it is more preferable that it is about 2-800 nm. By making the average thickness of the plasma polymerized film 3 within the above range, while preventing the dimensional accuracy of the joined body 1 obtained by joining the first base material 21 and the second base material 22 from being significantly reduced, The 1st base material 21 and the 2nd base material 22 can be joined more firmly.

That is, when the average thickness of the plasma polymerized film 3 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 plasma polymerized film 3 exceeds the upper limit, the dimensional accuracy of the joined body may be significantly reduced.
Furthermore, if the average thickness of the plasma polymerized film 3 is within the above range, a certain degree of shape followability is ensured for the plasma polymerized film 3. For this reason, for example, even when unevenness exists on the bonding surface 23 (surface adjacent to the plasma polymerization film 3) of the first base material 21, it follows the shape of the unevenness depending on the height of the unevenness. Thus, the plasma polymerization film 3 can be deposited. As a result, the plasma polymerized film 3 can absorb the unevenness and reduce the height of the unevenness generated on the surface.
In addition, the degree of the shape followability as described above becomes more prominent as the thickness of the plasma polymerization film 3 increases. Therefore, in order to ensure sufficient shape followability, the thickness of the plasma polymerization film 3 should be as thick as possible.

[3] Next, the two adherends 41 and 42 are overlapped so that the surface 31 of the plasma polymerization film 3 and the bonding surface 24 of the second base material 22 are in close contact (see FIG. 2D). . Thereby, the temporary joined body 5 shown in FIG.3 (e) is obtained (lamination process).
In addition, in the state of this temporary joined body 5, between the 1st to-be-adhered body 41 and the 2nd to-be-adhered body 42 is not joined. For this reason, the 1st to-be-adhered body 41 and the 2nd to-be-adhered body 42 can be shifted, and these relative positions can be adjusted. In this way, after the two adherends 41 and 42 are superposed, their positions can be easily fine-adjusted, so that the workability of the position adjustment is improved and the finally obtained joining The dimensional accuracy in the surface direction of the body 1 can be increased.
In particular, when the plasma polymerized film 3 is composed of polyorganosiloxane as a main material, the surface 31 of the plasma polymerized film 3 exhibits sufficient non-adhesiveness as described above. , 42 can freely adjust their positions. For this reason, the positions of the two adherends 41 and 42 can be finely adjusted particularly easily.

  Further, in obtaining the temporary bonded body 5 shown in FIG. 3 (e), the two adherends 41, so that the entire surface 31 of the plasma polymerized film 3 is covered with the bonding surface 24 of the second base material 22, 42 are superposed, but their relative positions may be offset from each other. That is, the first adherend 41 and the second adherend 42 may be overlapped so that a part of the surface 31 of the plasma polymerization film 3 is exposed.

[4] Next, as shown in FIG. 3 (e), energy is selectively applied to some predetermined regions 310 in the plasma polymerized film 3 in the obtained temporary joined body 5. Thereby, in the temporary joined body 5, a part of molecular bond of the plasma polymerization film | membrane 3 is cut | disconnected and activated (energy provision process).
The “activation” means a state in which molecular bonds in the vicinity of and inside the surface 31 of the plasma polymerization film 3 are cut, and unterminated bonds (unbonded or dangling bonds) are generated, It means a state in which a hydroxyl group is bonded to the cleaved bond or a state in which these states are mixed.

When energy is applied to the temporary bonded body, the molecular bonds in the vicinity of and inside the surface 31 of the plasma polymerized film 3 are broken, and atomic groups (leaving groups) are desorbed from the plasma polymerized film 3. As a result, the bond to which the leaving group is bonded becomes an unterminated bond (unbonded bond).
Further, when moisture is contained in the surrounding atmosphere, the moisture acts on the dangling bonds, so that the dangling hands are terminated with a hydroxyl group.

Here, the leaving group is, for example, selected from the group consisting of 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 containing each of these atoms. Those composed of at least one selected from the above are preferably used. Such a leaving group is relatively excellent in bond / elimination selectivity by energy application. For this reason, such a leaving group can highly control the adhesiveness developed in the plasma polymerized film 3.
Specific examples of leaving groups include, for example, alkyl groups such as methyl and ethyl groups, alkenyl groups such as vinyl and allyl groups, aldehyde groups, ketone groups, carboxyl groups, amino groups, amide groups, nitro groups, and the like. Group, halogenated alkyl group, mercapto group, sulfonic acid group, cyano group, isocyanate group and the like.

Among these groups, the leaving group is particularly preferably an alkyl group. Since the alkyl group has high chemical stability, the plasma polymerized film 3 containing the alkyl group has excellent weather resistance and chemical resistance.
For example, when the plasma polymerized film 3 is composed of polyorganosiloxane as a main material, an alkyl group such as a methyl group mainly acts as a leaving group.
Based on the above phenomenon, a predetermined region 310 of a part of the plasma polymerized film 3 is activated, and the plasma polymerized film 3 exhibits adhesiveness. And by this adhesiveness, the plasma polymerized film 3 and the second base material 22 are partially joined in the predetermined region 310 (see FIG. 3F). Thereby, the joined body 1 shown in FIG.

  As a method for applying energy to a predetermined region 310 of a part of the plasma polymerized film 3, any method may be used as long as it can activate the plasma polymerized film 3. Examples include a method of irradiating a part of the energy beam, (II) a method of heating a part of the temporary joined body 5, and (III) a method of applying a compressive force (physical energy) to a part of the temporary joined body 5. It is done. Since these methods can impart energy to the plasma polymerized film 3 relatively easily and efficiently, they are suitable as energy imparting methods.

Hereinafter, each method of (I), (II), and (III) is explained in full detail.
(I) In the case of irradiating a part of the predetermined region 310 of the temporary joined body 5 with energy rays, examples of energy rays include light such as ultraviolet rays and laser light, electromagnetic waves such as X-rays and γ rays, or these A combination of these energy rays. According to the method of irradiating energy rays, large energy can be applied in a short time. Accordingly, since the molecular structure in the plasma polymerized film 3 is not cut more than necessary, it is possible to avoid the deterioration of the characteristics of the plasma polymerized film 3.

In addition, when irradiating an energy beam to a part of the predetermined region 310 of the plasma polymerization film 3, if it is an energy beam having a high directivity such as a laser beam or an electron beam, the beam is irradiated toward a target direction. By doing so, it is possible to selectively and easily irradiate the predetermined region 310 with energy rays.
Further, even if the energy beam has a low directivity, the energy beam can be selectively irradiated to the predetermined region 310 if the plasma polymerization film 3 is irradiated so as to cover a region other than the predetermined region 310. Can do.

Specifically, for example, as shown in FIG. 3 (e), a mask 6 having a window portion 61 having a shape corresponding to the shape of a predetermined region 310 to be irradiated with ultraviolet rays of the plasma polymerization film 3 is provided. 6 may be irradiated with ultraviolet rays. In this way, it is possible to selectively irradiate the predetermined region 310 shown in FIG.
In order to irradiate the plasma polymerization film 3 with energy rays in this way, at least one of the two base materials 21 and 22 in the temporary joined body 5 must transmit the energy rays.

From this point of view, when activating the plasma polymerized film 3 by irradiating the temporary bonded body 5 with energy rays, at least one of the two base materials 21 and 22 has transparency to the energy rays. .
For example, when light such as ultraviolet rays or laser light is used as the energy ray, at least one of the two base materials 21 and 22 is a light-transmitting material, specifically, a transparent glass-based material, a resin-based material. What is comprised with the material should just be used.

When electromagnetic waves such as X-rays and γ-rays are used as energy rays, at least one of the two base materials 21 and 22 is composed of a light element material such as a silicon-based material, a glass-based material, or a resin-based material. What is done may be used.
In addition, when irradiating the energy beam to the temporary joined body 5, it goes without saying that the energy beam is irradiated from the first base material 21 or the second base material 22 side having transparency to the energy beam.

Among these energy rays, it is particularly preferable to use ultraviolet rays having a wavelength of about 150 to 300 nm, as shown in FIG. According to such ultraviolet rays, since the applied energy density is optimized, a wide range can be processed in a shorter time without unevenness while preventing the characteristics of the plasma polymerized film 3 from significantly deteriorating. For this reason, the plasma polymerization film 3 can be activated more efficiently. In addition, ultraviolet rays also have an advantage that they can be generated with simple equipment such as a UV lamp.
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 plasma polymerization film 3 is preferably from ^1mW / cm ^{2 ~1W} / cm 2 ^{approximately, 5mW / cm 2 ~50mW / cm} 2 of about It is more preferable that In this case, the separation distance between the UV lamp and the plasma polymerization film 3 is preferably about 3 to 3000 mm, and more preferably about 10 to 1000 mm.

The time for irradiating with ultraviolet rays is not particularly limited as long as the molecular bond of the plasma polymerized film 3 can be broken, but is preferably about 0.5 to 30 minutes, and preferably 1 to 10 minutes. More preferred is the degree.
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.

As described above, according to the method of irradiating energy rays, it is possible to easily apply energy selectively to the plasma polymerization film 3. Deterioration can be prevented.
In addition, according to the method of irradiating energy rays, a large amount of energy can be applied in a short time, so that energy can be applied more efficiently.
Furthermore, according to the method of irradiating energy rays, the magnitude of energy to be applied can be adjusted easily and accurately. Thereby, the degree of adhesiveness developed in the plasma polymerized film 3 can be easily controlled.

That is, by increasing the energy to be applied, the adhesiveness expressed in the plasma polymerized film 3 can be further increased. On the other hand, the adhesiveness expressed in the plasma polymerization film 3 can be suppressed by reducing the applied energy. Thereby, the joining strength of the joined body 1 finally obtained can be adjusted.
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.

  Moreover, it is preferable to irradiate such energy rays so that the energy is concentrated on the surface 31 of the plasma polymerization film 3 so as to be focused. In this way, molecular bonds near the surface 31 of the plasma polymerized film 3 can be selectively cut. Thereby, it can prevent more reliably that an energy ray cut | disconnects the molecular structure in the plasma polymerization film | membrane 3 more than necessary. As a result, it can be avoided more reliably that the characteristics of the plasma polymerized film 3 are significantly deteriorated.

  (II) When heating a predetermined region 310 of a part of the temporary joined body 5 (not shown), it is preferable to set the heating temperature to about 25 to 100 ° C, and more preferably to about 50 to 100 ° C. preferable. By heating at a temperature in such a range, it is possible to reliably activate the plasma polymerized film 3 while reliably preventing the base materials 21 and 22 from being altered or deteriorated by heat. If the heating temperature exceeds the upper limit, heat may be transferred to a region other than the predetermined region 310, and only the predetermined region 310 may not be selectively activated.

The heating time may be a time that can break the molecular bond of the plasma polymerized film 3, and specifically, it is preferably about 1 to 30 minutes if the heating temperature is within the above range. .
The temporary joined body 5 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.

  In addition, when using the method of irradiating infrared rays, the material in which at least one of the two base materials 21 and 22 in the temporary joining body 5 has light absorptivity (infrared absorptivity) like a silicon-type material is used. It is preferable that it is comprised. The first base material 21 or the second base material 22 made of such a material efficiently generates heat by absorbing infrared rays. Thereby, the plasma polymerization film | membrane 3 can be heated efficiently.

  Moreover, when using the method using a heater or the method of making it contact with a flame, at least one of the two base materials 21 and 22 is comprised with the material excellent in thermal conductivity like a metallic material. Is preferred. Thereby, the heat energy of the heater or flame can be efficiently transmitted to the plasma polymerization film 3 through the first base material 21 or the second base material 22 made of such a material. As a result, the plasma polymerization film 3 can be efficiently heated.

In addition, when the thermal expansion coefficient of the two base materials 21 and 22 is substantially equal, it is preferable to heat the temporary joined body 5 on the above conditions, but the thermal expansion coefficient of the two base materials 21 and 22 is When they 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, although it depends on the difference in thermal expansion coefficient between the two base materials 21 and 22, it is preferable to perform the bonding at a temperature of about 25 to 50 ° C, and it is preferable to perform the bonding at a temperature of about 25 to 40 ° C. More preferred. In such a temperature range, even if the difference in thermal expansion coefficient between the two base materials 21 and 22 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 warpage, peeling, and the like in the joined body 1.
In this case, when the difference in thermal expansion coefficient between the two base materials 21 and 22 is 5 × 10 ⁻⁵ / K or more, it is strongly recommended that the bonding be performed at the lowest possible temperature as described above. Is done.

  (III) When compressive force is applied to a part of the predetermined region 310 of the temporary joined body 5 (not shown), the direction in which the first base material 21 and the second base material 22 of the temporary joined body 5 approach each other. In addition, the compression is preferably performed at a pressure of about 0.2 to 10 MPa, and more preferably compressed at a pressure of about 1 to 5 MPa. Thereby, moderate energy can be easily given with respect to the plasma polymerization film | membrane 3 only by compressing the temporary joining body 5. FIG. As a result, the plasma polymerization film 3 can be reliably activated.

In addition, although compression force may exceed the said upper limit, depending on the constituent material of each base material 21 and 22, there exists a possibility that damage etc. may arise in each base material 21 and 22. In addition, when the compressive force exceeds the upper limit, regions other than the predetermined region 310 may be joined.
Moreover, 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.

Energy can be imparted to the plasma polymerized film 3 by the above methods (I), (II), and (III).
The application of energy to the plasma polymerization film 3 may be performed in any atmosphere, and specifically, the atmosphere, an oxidizing gas atmosphere such as oxygen, a reducing gas atmosphere such as hydrogen, nitrogen, An inert gas atmosphere such as argon, a reduced pressure (vacuum) atmosphere obtained by reducing these atmospheres, and the like can be given, 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 energy can be applied more easily.

Further, when the plasma polymerized film 3 is composed of an organometallic polymer, when energy is applied to the plasma polymerized film 3, the organic component is removed from the plasma polymerized film 3 and the conductive component is dominant. Become. As a result, conductivity develops in the plasma polymerized film 3 to which energy is applied (through the activation process).
Depending on the type of the organometallic polymer, some may have conductivity even if energy is not applied. Such an organometallic polymer has conductivity immediately after being formed as in step [2].

When energy is applied as described above, adhesiveness is expressed in the plasma polymerized film 3, and this adhesiveness is presumed to be based on the following mechanism.
For example, when energy is applied to the temporary bonded body 5, the plasma polymerization film 3 is activated. In some cases, the bonding surface 24 of the second base material 22 is similarly activated. As an example, a case where hydroxyl groups are exposed on the surface 31 and the bonding surface 24 by this activation will be described. The hydroxyl groups exposed on the surface 31 and the hydroxyl groups exposed on the bonding surface 24 are attracted to each other by hydrogen bonding. An attractive force is generated between them. By this attractive force, the plasma polymerized film 3 and the second base material 22 are joined, and the joined body 1 is obtained.
Further, the hydroxyl groups attracting each other by the hydrogen bond are cleaved from the surface with dehydration condensation depending on the temperature condition or the like. As a result, at the contact interface between the plasma polymerized film 3 and the second base material 22, the bonds in which the hydroxyl groups are bonded are recombined. Thereby, the plasma polymerization film | membrane 3 and the 2nd base material 22 are joined more firmly, and the joining body 1 with high joining strength is obtained.

  The bonded body 1 thus obtained is not bonded mainly based on a physical bond such as an anchor effect, as in an adhesive used in a conventional bonding method, but is a short time such as a covalent bond. The two adherends 41 and 42 are joined based on the strong chemical bond generated in step (b). For this reason, the bonded body 1 can be formed in a short time, is extremely difficult to peel off, and is difficult to cause uneven bonding.

Further, according to the bonding method of the present invention, unlike the conventional solid bonding, a heat treatment at a high temperature (for example, 700 ° C. or higher) is not required. Can be used for joining.
Moreover, since the two base materials 21 and 22 are joined together via the plasma polymerization film 3, there is also an advantage that there is no restriction in the material of the base material as in the conventional solid joining.

From the above, according to the present invention, the range of selection of the constituent materials of the base materials 21 and 22 can be expanded.
Furthermore, since conventional solid bonding is not bonding via a bonding layer, when there is a large difference in the coefficient of thermal expansion between two substrates, when these are bonded, a large stress based on the difference is bonded. Concentration at the interface may cause problems such as peeling, but according to the present invention, stress concentration is mitigated through the plasma polymerized film 3, and peeling in the bonded body 1 can be reliably prevented. it can.

  Moreover, according to this embodiment, when joining the 1st base material 21 and the 2nd base material 22, rather than joining these joining surfaces (surfaces which mutually oppose), a part of them is joined. Only the region (predetermined region 310) is selectively joined. At the time of bonding, the region to be bonded can be easily selected only by controlling the region to which energy is applied to the plasma polymerized film 3. Thereby, since the area and shape of the junction part of the 1st base material 21 and the 2nd base material 22 can be controlled, for example, the joint strength of the joined body 1 can be adjusted easily. As a result, for example, the joined body 1 is obtained in which the joined portion can be easily separated.

Further, by controlling the area and shape of the joint portion between the first base material 21 and the second base material 22, local concentration of stress generated in the joint portion can be reduced. Thereby, for example, even when the difference in thermal expansion coefficient between the first base material 21 and the second base material 22 is large, the base materials 21 and 22 can be reliably bonded.
Furthermore, according to the bonding method of the present invention, in the region other than the predetermined region 310 to be bonded in the surface 31 of the plasma polymerized film 3 included in the first base material 21, the plasma polymerized film 3 and the second base material are used. There is a slight gap between the two. In order to make use of this gap, a closed space or a flow path can be formed between the first base material 21 and the second base material 22 by appropriately adjusting the shape of the predetermined region 310.

  Moreover, the plasma polymerization film | membrane 3 becomes a solid thing which does not have fluidity | liquidity. For this reason, by using the plasma polymerized film 3 as a bonding layer, the thickness and shape of the bonding layer (plasma polymerized film 3) hardly change compared to a conventional liquid or viscous liquid adhesive. Thereby, the dimensional accuracy of the joined body 1 obtained using the plasma polymerized film 3 is remarkably higher than the conventional one. Furthermore, since the time required for curing the adhesive is not required, strong bonding can be achieved in a short time.

  Further, in the present embodiment, of the two adherends 41 and 42, the first adherend 41 has the plasma polymerized film 3, but the second adherend 42 has the plasma polymerized film. Not done. Therefore, when the plasma polymerized film 3 is manufactured, the first base material 21 is exposed to plasma for a relatively long time, but the second base material 22 is not exposed to plasma. For this reason, even if the 2nd base material 22 is comprised with the material with low durability with respect to a plasma, there is no possibility that the 2nd base material 22 may change and deteriorate. Therefore, the constituent material of the second base material 22 has an advantage that it can be selected from a wide range of materials without considering durability against plasma.

The joined body 1 thus obtained preferably has a joining strength between the first base material 21 and the second base material 22 of 5 MPa (50 kgf / cm ² ) or more, preferably 10 MPa (100 kgf / cm ² ) or more is more preferable. The bonded body 1 having such bonding strength can sufficiently prevent the peeling. As will be described later, when the droplet discharge head is configured using the joined body 1, a droplet discharge head having excellent durability can be obtained. Moreover, according to the joining method of the present invention, it is possible to efficiently produce the joined body 1 in which the first base material 21 and the second base material 22 are joined with the above-described great joint strength.

Further, when the plasma polymerization film 3 is composed of an organometallic polymer, conductivity is developed by applying energy to the plasma polymerization film 3. The resistivity of the plasma polymerization film 3 conductive is expressed in this way, although slightly different depending on the composition of the material, but preferably not more than ^{1 × 10 -3 Ω · cm,} 1 × 10 -4 Ω -More preferably, it is cm or less. If the resistivity of the plasma polymerized film 3 that exhibits conductivity through the energy application step is sufficiently low, the plasma polymerized film can be sufficiently used as a wiring with little loss.

  After obtaining the joined body 1, at least one of the following three steps ([5A], [5B], and [5C]) is performed on the joined body 1 as necessary. You may do it. Thereby, the joint strength of the joined body 1 can be further improved. Further, when the plasma polymerized film 3 is composed of an organometallic polymer, the conductivity expressed in the plasma polymerized film 3 can be further improved by performing the following three steps.

[5A] As shown in FIG. 3G, the predetermined region 310 of the obtained bonded body 1 is selectively pressurized in a direction in which the base materials 21 and 22 approach each other.
Thereby, the plasma polymerization film | membrane 3 and the 2nd base material 22 come closer. As a result, for example, the dehydration condensation in the step [4] is promoted. As a result, the bonding strength in the predetermined region 310 of the bonded body 1 can be further increased.
At this time, the pressure at the time of pressurizing the bonded body 1 is a pressure that does not damage the bonded body 1 and is preferably as high as possible. Thereby, the joint strength in the joined body 1 can be increased in proportion to the pressure.

In addition, what is necessary is just to adjust this pressure suitably according to conditions, such as a constituent material and thickness of each base material 21 and 22, a joining apparatus. Specifically, although it varies slightly depending on the constituent materials and thicknesses of the base materials 21 and 22, it is preferably about 0.2 to 10 MPa, more preferably about 1 to 5 MPa. Thereby, the joining strength of the joined body 1 can be reliably increased. In addition, although this pressure may exceed the said upper limit, depending on the constituent material of each base material 21 and 22, there exists a possibility that damage etc. may arise in each base material 21 and 22. When the compressive force exceeds the upper limit, there is a possibility that regions other than the predetermined region 310 may be joined.
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 time for applying the compressive force can be shortened as the compressive force increases.

[5B] As shown in FIG. 3G, the predetermined region 310 of the obtained bonded body 1 is selectively heated.
Thereby, for example, dehydration condensation of hydroxyl groups further proceeds at the interface between the plasma polymerized film 3 and the second base material 22. As a result, the bonding strength in the predetermined region 310 of the bonded body 1 can be further increased.
At this time, the temperature at the time of heating the bonded body 1 is not particularly limited as long as it is higher than room temperature and lower than the heat resistance temperature of the bonded body 1, but is preferably about 25 to 100 ° C., more preferably 50 to 100 ° C. About ℃. By heating at a temperature in such a range, it is possible to reliably increase the bonding strength of the bonded body 1 while reliably preventing the bonded body 1 from being altered or deteriorated by heat.

The heating time is not particularly limited, but is preferably about 1 to 30 minutes.
Moreover, when performing both said process [5A] and [5B], it is preferable to perform these simultaneously. That is, as shown in FIG. 3G, it is preferable to heat the bonded body 1 while applying pressure. Thereby, the effect by pressurization and the effect by heating are exhibited synergistically, and the joint strength of the joined body 1 can be particularly increased.

[5C] The predetermined region 310 of the obtained bonded body 1 is selectively irradiated with ultraviolet rays (or other energy rays) (not shown).
Thereby, more chemical bonds are formed between the plasma polymerized film 3 and the second base material 22, and the bonding strength of the predetermined region 310 of the bonded body 1 can be particularly increased.
The conditions of the ultraviolet rays irradiated at this time may be equivalent to the conditions of the ultraviolet rays shown in the step [4]. Moreover, when performing this process [5C], it is required that at least one of the two base materials 21 and 22 has translucency. Then, by irradiating ultraviolet rays from the side of the substrate having translucency, the ultraviolet rays can be reliably irradiated to the plasma polymerization film 3.

By performing the steps as described above, the bonding strength of the bonded body 1 can be further improved.
Each of these steps [5A], [5B] and [5C] may be performed continuously in time after the completion of the step [4], or after a certain time. It may be.

<< Second Embodiment >>
Next, a second embodiment of the joining method of the present invention will be described.
4 and 5 are views (longitudinal sectional views) for explaining a second embodiment of the joining method of the present invention. In the following description, the upper side in FIGS. 4 and 5 is referred to as “upper” and the lower side is referred to as “lower”.

Hereinafter, although 2nd Embodiment of the joining method is described, it demonstrates centering around difference with the joining method concerning the said 1st Embodiment, and the description is abbreviate | omitted about the same matter.
In the bonding method according to the present embodiment, a first adherend 41 having a plasma polymerized film 301 on the first substrate 21 and a second substrate having a plasma polymerized film 302 on the second substrate 22 are used. Except for joining the body 42, it is the same as in the first embodiment.

  That is, in the bonding method according to the present embodiment, the plasma polymerized film 301 is formed on the first substrate 21 to produce the first adherend 41, and the plasma polymerized film is formed on the second substrate 22. 302 is formed, and the adherend preparation step for producing the second adherend 42 is superposed so that the plasma polymerized film 301 and the plasma polymerized film 302 are in close contact with each other to obtain the temporary joined body 5. A stacking step and an energy applying step of selectively applying energy to a part of the predetermined region 310 in the temporary bonded body 5 to obtain a bonded body are included. Hereinafter, each process will be described sequentially.

[1] First, as in the first embodiment, as shown in FIGS. 4A to 4C, a plasma polymerization film 301 is formed on the first base material 21. Similarly, a plasma polymerization film 302 is formed on the second base material 22. As a result, a first adherend 41 and a second adherend 42 are obtained (adherent preparation step).
In this case, the constituent material of the plasma polymerized film 301 and the constituent material of the plasma polymerized film 302 may be different from each other, but are preferably the same material. Thereby, the affinity between the plasma polymerized film 301 and the plasma polymerized film 302 is improved. As a result, the plasma-polymerized film 301 and the plasma-polymerized film 302 can be firmly bonded through the steps described later.

[2] Next, as shown in FIG. 4D, the two adherends 41 and 42 are overlapped so that the plasma polymer films 301 and 302 are in close contact with each other. Thereby, the temporary joined body 5 is obtained (lamination process).
In addition, in the state of this temporary joined body 5, between the 1st to-be-adhered body 41 and the 2nd to-be-adhered body 42 is not joined. For this reason, similarly to the first embodiment, the first adherend 41 and the second adherend 42 can be shifted and their relative positions can be adjusted.

[3] Next, energy is selectively applied to some of the predetermined regions 310 of the plasma polymerized films 301 and 302 in the obtained temporary bonded body 5. Thereby, in the temporary joined body 5, a part of molecular bond of the plasma polymerization film | membrane 3 is cut | disconnected and activated (energy provision process).
Specifically, as in the first embodiment, as shown in FIG. 5E, energy is applied by selectively irradiating the predetermined region 310 with ultraviolet rays through the mask 6.

When energy is applied as described above, adhesiveness develops in the predetermined region 310 of each plasma polymerized film 301, 302. This adhesiveness is expressed by the following two mechanisms (i), Presumed to be based on both or one of ii).
(I) Here, as an example, a case where a hydroxyl group is generated in each of the plasma polymerized films 301 and 302 by applying energy will be described as an example. When hydroxyl groups are generated in the plasma polymerization films 301 and 302 in an overlapped state, these hydroxyl groups attract each other by hydrogen bonding, and an attractive force is generated between the hydroxyl groups. It is assumed that the two adherends 41 and 42 are joined by this attractive force.
Further, the hydroxyl groups attracted to each other by this hydrogen bond are cut from the respective plasma polymerized films 301 and 302 with dehydration condensation depending on the temperature condition or the like. As a result, between the plasma polymerized films 301 and 302, the bonds in which the hydroxyl groups are bonded are bonded. Thereby, in the predetermined area | region 310, it is guessed that each plasma polymerization film | membrane 301,302 joins and it becomes one plasma polymerization film | membrane. As a result, the first adherend 41 and the second adherend 42 are bonded more firmly.

  (Ii) When energy is applied to the plasma polymerized films 301 and 302 in the temporary bonded body 5, dangling bonds are generated on the surfaces 303 and 304 of the plasma polymerized films 301 and 302 and inside. And when a dangling bond arises in each plasma polymerization film 301 and 302 which overlapped, adjacent dangling bonds recombine. Since this recombination occurs in a complicated manner so as to overlap (entangle) with each other, a network-like bond is formed at the bonding interface. As a result, it is presumed that in the predetermined region 310, the respective base materials constituting the respective plasma polymerized films 301 and 302 are directly joined to form one plasma polymerized film. As a result, it is assumed that the two adherends 41 and 42 are joined.

By the mechanism (i) or (ii) as described above, the joined body 1 as shown in FIG. 5 (f) is obtained.
In the joining method according to the present embodiment, the same actions and effects as the joining method according to the first embodiment can be obtained.
In the present embodiment, the plasma polymer films 301 and 302 are formed on the base materials 21 and 22, respectively, and the plasma polymer films 301 and 302 are bonded to each other. In comparison, the bonding strength of the bonded body 1 can be improved.

Further, when compared with the first embodiment, in this embodiment, the plasma polymerized film 302 is formed on the second base material 22 in advance, so that the bonded body is formed by the constituent material of the second base material 22. The bonding strength of 1 becomes difficult to be affected. For this reason, for example, in the bonding method according to the first embodiment, the second substrate made of a material that has low adhesion to the plasma polymerized film 302 and reduces the bonding strength of the bonded body 1. Even when 22 is used, according to the bonding method according to the present embodiment, the first base material 21 and the second base material 22 can be bonded more firmly.
After obtaining the joined body 1, at least one of the three steps ([5A], [5B] and [5C]) in the first embodiment is performed on the joined body 1 as necessary. One process may be performed.

  For example, as illustrated in FIG. 5G, the base materials 21 and 22 of the joined body 1 are brought closer to each other by heating the joined body 1 while applying pressure. This promotes dehydration condensation of hydroxyl groups and recombination of dangling bonds at the interfaces of the plasma polymerized films 301 and 302. The plasma polymer films 301 and 302 are almost completely integrated into a single plasma polymer film in the predetermined region 310. As a result, the joint strength of the joined body 1 can be further improved.

FIG. 6 shows another configuration example of the joined body according to the present embodiment.
In this example, as shown in FIG. 6A, the predetermined region 310 of the temporary joined body 5 is selectively irradiated with ultraviolet rays.
The predetermined area 310 is a pattern in which a plurality of rectangular areas are set to be distributed at predetermined intervals.
Then, using the mask 6 having the window portion 61 having a shape corresponding to this pattern, the predetermined region 310 of the temporary bonded body 5 is selectively irradiated with ultraviolet rays.

When the ultraviolet rays are irradiated in this way, adhesiveness is partially developed in each of the plasma polymerization films 301 and 302 located in the predetermined region 310 of the temporary bonded body 5.
As a result, as shown in FIG. 6B, the joined body 1 is obtained in which the respective plasma polymerization films 301 and 302 are partially joined in the predetermined region 310.
In such a bonded body 1, by appropriately controlling the area and shape of the predetermined region 310, for example, the bonding strength of the bonded body 1 is adjusted, or the local concentration of stress generated in the bonded portion (predetermined region 310) is reduced. You can do it.

<< Third Embodiment >>
Next, a third embodiment of the joining method of the present invention will be described.
7 and 8 are views (longitudinal sectional views) for explaining a third embodiment of the joining method of the present invention. In the following description, the upper side in FIGS. 7 and 8 is referred to as “upper” and the lower side is referred to as “lower”.

Hereinafter, the third embodiment of the bonding method will be described. However, the difference from the bonding method according to the first embodiment and the second embodiment will be mainly described, and description of similar matters will be omitted. .
In the bonding method according to the present embodiment, the plasma polymerized film 3a is selectively formed only on a part of the predetermined region 310 in the bonding surface 23 of the first base material 21, and the first base material 21 and the plasma are formed. The same as in the first embodiment, except that the first adherend 41 including the polymer film 3a is manufactured and the first adherend 41 and the second adherend 42 are joined. It is.

  That is, in the bonding method according to the present embodiment, the first base material 21 and the second base material 22 (second adherend 42) are prepared, and the bonding surface 23 of the first base material 21 is formed. The plasma polymerized film 3a is formed in a predetermined region 310 to prepare the first adherend 41, and the plasma polymerized film 3a and the second adherend 42 are in close contact with each other. These are superposed to have a laminating step for obtaining the temporary joined body 5 and an energy applying step for applying energy to the temporary joined body 5 to obtain a joined body. Hereinafter, each process will be described sequentially.

[1] First, the first base material 21 and the second base material 22 (second adherend 42) are prepared. Each of the base materials 21 and 22 has the same configuration as that of the first embodiment.
Next, as shown in FIG. 7A, a mask 6 having a window portion 61 having a shape corresponding to the shape of the predetermined region 310 is provided above the bonding surface 23 of the first base material 21.
Next, a plasma polymerization film 3 a is formed on the bonding surface 23 of the first base material 21 through the mask 6. The polymer produced by the plasma polymerization method is deposited on the bonding surface 23 of the first base material 21. At this time, the polymer passes through the window 61 of the mask 6, so that the polymer is polymerized only in the predetermined region 310. Things accumulate. As a result, a plasma polymerization film 3a is formed in a predetermined region 310 of a part of the bonding surface 23 of the first base material 21 (see FIG. 7B). Thereby, the 1st to-be-adhered body 41 provided with the 1st base material 21 and the plasma polymerization film | membrane 3a provided in the predetermined area | region 310 of a part of joint surface 23 of the 1st base material 21 is produced. (Adherent preparation step).
In FIG. 7A, the mask 6 and the first base material 21 are separated from each other, but the mask 6 may be provided so as to be in contact with the bonding surface 23 of the first base material 21.
[2] Next, as shown in FIG. 7 (c), the two polymerized films 3a and the bonding surface 24 of the second base material 22 (second adherend 42) are in close contact with each other. The landing bodies 41 and 42 are overlapped. Thereby, the temporary joined body 5 shown in FIG.8 (d) is obtained (lamination process).

[3] Next, energy is applied to the plasma polymerization film 3a in the obtained temporary joined body 5. Thereby, in the temporary joined body 5, a part of molecular bond of the plasma polymerization film 3a is cut | disconnected and activated (energy provision process).
Specifically, as shown in FIG. 8E, energy is applied by irradiating ultraviolet rays. As a result, adhesiveness develops in the plasma polymerization film 3a. The plasma polymerized film 3 a and the second base material 22 are partially bonded in the predetermined region 310 by this adhesiveness. Thereby, the joined body 1 is obtained.
When energy is applied in this step, energy may be selectively applied to the plasma polymerization film 3a, but energy may be applied to the entire temporary joined body 5.
Further, the energy applied to the temporary joined body 5 may be applied by any method, for example, by the method described in the first embodiment.

In the joining method according to the present embodiment, the same operations and effects as those of the joining method according to the first embodiment and the second embodiment can be obtained.
Further, a gap 3c having a separation distance (height) corresponding to the thickness of the plasma polymerization film 3a is formed between the first base material 21 and the second base material 22 in a region other than the predetermined region 310. (See FIG. 8F). Therefore, by appropriately adjusting the shape of the predetermined region 310 and the thickness of the plasma polymerization film 3a, a closed space, a flow path, or the like having a desired shape is formed between the first base material 21 and the second base material 22. Can be easily formed.
After obtaining the joined body 1, at least one of the three steps ([5A], [5B] and [5C]) in the first embodiment is performed on the joined body 1 as necessary. One process may be performed. Thereby, the joint strength of the joined body 1 can be further improved.

<< Fourth Embodiment >>
Next, a fourth embodiment of the joining method of the present invention will be described.
9 and 10 are views (longitudinal sectional views) for explaining a fourth embodiment of the joining method of the present invention. In the following description, the upper side in FIGS. 9 and 10 is referred to as “upper” and the lower side is referred to as “lower”.

Hereinafter, the fourth embodiment of the bonding method will be described. However, the difference from the bonding method according to the first to third embodiments will be mainly described, and description of similar matters will be omitted. .
In the bonding method according to the present embodiment, the plasma polymerization films 3a and 3b are selectively formed only on some of the predetermined regions 310a and 310b of the bonding surfaces 23 and 24 of the base materials 21 and 22, respectively. Each of the adherends 41 and 42 is manufactured and is the same as the first embodiment except that the first adherend 41 and the second adherend 42 are joined.

  That is, in the bonding method according to the present embodiment, the plasma polymerized film 3a is formed in the predetermined region 310a of the bonding surface 23 of the first base material 21 to produce the first adherend 41 and the second substrate. The plasma polymerized film 3b is formed in the predetermined region 310b of the bonding surface 24 of the material 22, and the adherend preparation step for producing the second adherend 42 and the plasma polymerized films 3a and 3b are in close contact with each other. A stacking step for obtaining the temporary joined body 5 by superimposing the first adherend 41 and the second adherend 42, and an energy applying step for obtaining a joined body by applying energy to the temporary joined body 5. Have Hereinafter, each process will be described sequentially.

[1] First, as shown in FIG. 9A, a mask 6 having a window portion 61 having a shape corresponding to the shape of each of the predetermined regions 310a and 310b is provided above the base materials 21 and 22, respectively.
Next, the plasma polymerization films 3 a and 3 b are formed on the bonding surfaces 23 and 24 of the base materials 21 and 22 through the mask 6, respectively. Polymers generated by the plasma polymerization method are deposited on the joint surfaces 23 and 24 of the base materials 21 and 22. At this time, the polymer passes through the window portion 61 of the mask 6, thereby causing each predetermined region. Polymers are deposited only on 310a and 310b. As a result, each plasma polymerization film 3a, 3b is formed in each predetermined region 310a, 310b of a part of the joint surfaces 23, 24 of each substrate 21, 22 (see FIG. 9B). Thereby, the 1st to-be-adhered body 41 provided with the 1st base material 21 and the plasma polymerization film | membrane 3a provided in the predetermined area | region 310a of a part of joining surface 23 of the 1st base material 21, and 2nd The second adherend 42 including the base material 22 and the plasma polymerization film 3b provided in a predetermined region 310b of a part of the bonding surface 24 of the second base material 22 is manufactured (adherence body). Preparation step).
In FIG. 9A, the mask 6 is separated from the first base material 21 and the second base material 22, but the bonding surface 23 of the first base material 21 and the second base material 22 The mask 6 may be provided so as to be in contact with the bonding surface 24.
[2] Next, as shown in FIG. 9C, the first adherend 41 and the second adherend 42 are overlapped so that the plasma polymerized film 3a and the plasma polymerized film 3b are in close contact with each other. Match. Thereby, the temporary joined body 5 shown in FIG.10 (d) is obtained (lamination process).

[3] Next, energy is applied to each of the plasma polymerized films 3 a and 3 b in the obtained temporary joined body 5. Thereby, in the temporary joined body 5, a part of molecular bond of each plasma polymerization film | membrane 3a, 3b is cut | disconnected and activated (energy provision process).
Specifically, as shown in FIG. 10E, energy is applied by irradiating ultraviolet rays. As a result, adhesiveness develops in each plasma polymerized film 3a, 3b. The plasma polymerized film 3a and the plasma polymerized film 3b are bonded to each other by this adhesiveness. Thereby, the joined body 1 is obtained.

In the joining method according to the present embodiment, the same operations and effects as the joining methods according to the first to third embodiments can be obtained.
In addition, between the first base material 21 and the second base material 22, the total of the thickness of the plasma polymerized film 3 a and the thickness of the plasma polymerized film 3 b is provided in a region other than the predetermined region 310 a and the predetermined region 310 b. A gap 3c having a corresponding separation distance (height) is formed (see FIG. 10F). Therefore, by appropriately adjusting the shape of each predetermined region 310a, 310b and the thickness of each plasma polymerization film 3a, 3b, a desired shape can be formed between the first base material 21 and the second base material 22. A closed space, a flow path, and the like can be easily formed.

After obtaining the joined body 1, at least one of the three steps ([5A], [5B] and [5C]) in the first embodiment is performed on the joined body 1 as necessary. One process may be performed. Thereby, the joint strength of the joined body 1 can be further improved.
Further, the shape of the plasma polymerized film 3a (planar shape of the predetermined region 310a) and the shape of the plasma polymerized film 3b (planar shape of the predetermined region 310b) may be the same as in this embodiment. They may be different from each other.

The joining method according to each of the embodiments as described above can be used to join various members.
Examples of members used for such bonding include semiconductor elements such as transistors, diodes, and memories, piezoelectric elements such as crystal oscillators, optical elements such as reflectors, optical lenses, diffraction gratings, and optical filters. , Optical conversion elements such as solar cells, semiconductor substrates and semiconductor elements mounted on them, insulating substrates and wiring or electrodes, inkjet recording heads, microreactors, microelectromechanical systems (MEMS) components such as micromirrors, pressure Sensor parts such as sensors, acceleration sensors, package parts for semiconductor elements and electronic parts, magnetic recording media, magneto-optical recording media, recording media such as optical recording media, liquid crystal display elements, organic EL elements, electrophoretic display elements Such display element parts, fuel cell parts, and the like.

<Droplet ejection head>
Here, an embodiment in which the joined body of the present invention is applied to an ink jet recording head (droplet ejection head) will be described.
FIG. 11 is an exploded perspective view showing an ink jet recording head (droplet discharge head) obtained by applying the joined body of the present invention, and FIG. 12 shows the configuration of the main part of the ink jet recording head shown in FIG. FIG. 13 is a schematic view showing an embodiment of an ink jet printer including the ink jet recording head shown in FIG. In addition, FIG. 11 is shown upside down from the state normally used.
An ink jet recording head (droplet discharge head of the present invention) 10 shown in FIG. 11 is mounted on an ink jet printer (droplet discharge apparatus of the present invention) 9 as shown in FIG.

An ink jet printer 9 shown in FIG. 13 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 the like. 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 an ink jet recording head 10 (hereinafter simply referred to as “head 10”) having a large number of nozzle holes 111 at a lower portion thereof, an ink cartridge 931 that supplies ink to the head 10, the head 10 and And a carriage 932 on which the ink cartridge 931 is mounted.
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 10 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 recording paper P feeding path (recording paper P) interposed therebetween. The drive roller 952b is connected to the paper feed motor 951. 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 piezoelectric element driving circuit that drives the piezoelectric element (vibration source) 14 to control the ink ejection timing, A driving circuit for driving the printing device 94 (carriage motor 941), a driving circuit for driving the paper feeding device 95 (paper feeding motor 951), a communication circuit for obtaining print data from the host computer, and these electrically And a CPU that is connected 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 piezoelectric element 14, the printing device 94, and the paper feeding device 95 are each activated by this drive signal. As a result, printing is performed on the recording paper P.

Hereinafter, the head 10 (the droplet discharge head of the present invention) will be described in detail with reference to FIGS. 11 and 12.
The head 10 includes a head main body 17 including a nozzle plate 11, an ink chamber substrate 12, a vibration plate 13, and a piezoelectric element (vibration source) 14 bonded to the vibration plate 13, and a base body that houses the head main body 17. 16. The head 10 constitutes an on-demand piezo jet head.

The nozzle plate 11 is made of, for example, a silicon-based material such as SiO ₂ , SiN, or quartz glass, a metal-based material such as Al, Fe, Ni, Cu, or an alloy containing these, or an oxide-based material such as alumina or iron oxide. The material is composed of carbon-based materials such as carbon black and graphite.
A number of nozzle holes 111 for discharging ink droplets are formed in the nozzle plate 11. The pitch between these nozzle holes 111 is appropriately set according to the printing accuracy.

An ink chamber substrate 12 is fixed (fixed) to the nozzle plate 11.
The ink chamber substrate 12 includes a plurality of ink chambers (cavities, pressure chambers) 121 and a reservoir chamber that stores ink supplied from the ink cartridge 931 by the nozzle plate 11, side walls (partition walls) 122, and a vibration plate 13 described later. 123 and a supply port 124 for supplying ink from the reservoir chamber 123 to each ink chamber 121 are partitioned.

Each ink chamber 121 is formed in a strip shape (cuboid shape), and is disposed corresponding to each nozzle hole 111. Each ink chamber 121 has a variable volume due to vibration of a diaphragm 13 described later, and is configured to eject ink by this volume change.
As a base material for obtaining the ink chamber substrate 12, for example, a silicon single crystal substrate, various glass substrates, various resin substrates and the like can be used. Since these substrates are general-purpose substrates, the manufacturing cost of the head 10 can be reduced by using these substrates.

On the other hand, a vibration plate 13 is bonded to the ink chamber substrate 12 on the side opposite to the nozzle plate 11, and a plurality of piezoelectric elements 14 are provided on the vibration plate 13 on the side opposite to the ink chamber substrate 12.
A communication hole 131 is formed at a predetermined position of the diaphragm 13 so as to penetrate in the thickness direction of the diaphragm 13. Ink can be supplied from the ink cartridge 931 to the reservoir chamber 123 through the communication hole 131.

Each piezoelectric element 14 has a piezoelectric layer 143 interposed between the lower electrode 142 and the upper electrode 141, and is disposed corresponding to the substantially central portion of each ink chamber 121. Each piezoelectric element 14 is electrically connected to a piezoelectric element drive circuit and is configured to operate (vibrate, deform) based on a signal from the piezoelectric element drive circuit.
Each piezoelectric element 14 functions as a vibration source, and the diaphragm 13 vibrates due to vibration of the piezoelectric element 14 and functions to instantaneously increase the internal pressure of the ink chamber 121.
The base body 16 is made of, for example, various resin materials, various metal materials, and the like, and the nozzle plate 11 is fixed and supported on the base body 16. That is, the edge of the nozzle plate 11 is supported by the step 162 formed on the outer periphery of the recess 161 in a state where the head body 17 is housed in the recess 161 provided in the base body 16.

Among the above-described bonding between the nozzle plate 11 and the ink chamber substrate 12, bonding between the ink chamber substrate 12 and the vibration plate 13, and bonding between the nozzle plate 11 and the substrate 16, the bonding according to the present invention is performed. The method is used.
In other words, the present invention is provided in at least one place among the joined body of the nozzle plate 11 and the ink chamber substrate 12, the joined body of the ink chamber substrate 12 and the vibration plate 13, and the joined body of the nozzle plate 11 and the substrate 16. The joined body is applied.

Such a head 10 is joined by interposing a plasma polymerization film at the joining interface. For this reason, the bonding strength and chemical resistance at the bonding interface are increased, and thereby the durability and liquid-tightness of the ink stored in each ink chamber 121 are increased. As a result, the head 10 becomes highly reliable.
In addition, since highly reliable bonding can be performed at a very low temperature, it is advantageous in that a large-area head can be formed even with materials having different linear expansion coefficients.

  Such a head 10 is in a state where a predetermined ejection signal is not input via the piezoelectric element driving circuit, that is, in a state where no voltage is applied between the lower electrode 142 and the upper electrode 141 of the piezoelectric element 14. The piezoelectric layer 143 is not deformed. For this reason, the vibration plate 13 is not deformed, and the volume of the ink chamber 121 is not changed. Therefore, no ink droplet is ejected from the nozzle hole 111.

  On the other hand, in a state where a predetermined ejection signal is input via the piezoelectric element driving circuit, that is, in a state where a constant voltage is applied between the lower electrode 142 and the upper electrode 141 of the piezoelectric element 14, the piezoelectric layer 143 is applied. Deformation occurs. As a result, the diaphragm 13 is greatly deflected, and the volume of the ink chamber 121 is changed. At this time, the pressure in the ink chamber 121 increases instantaneously, and ink droplets are ejected from the nozzle holes 111.

  When the ejection of one ink is completed, the piezoelectric element driving circuit stops applying the voltage between the lower electrode 142 and the upper electrode 141. As a result, the piezoelectric element 14 returns almost to its original shape, and the volume of the ink chamber 121 increases. At this time, a pressure (pressure in the positive direction) from the ink cartridge 931 toward the nozzle hole 111 acts on the ink. Therefore, air is prevented from entering the ink chamber 121 from the nozzle hole 111, and an amount of ink corresponding to the amount of ink discharged is supplied from the ink cartridge 931 (reservoir chamber 123) to the ink chamber 121.

In this manner, in the head 10, arbitrary (desired) characters and figures can be printed by sequentially inputting ejection signals to the piezoelectric elements 14 at the positions to be printed via the piezoelectric element driving circuit. it can.
The head 10 may have an electrothermal conversion element instead of the piezoelectric element 14. That is, the head 10 may have a configuration (so-called “bubble jet method” (“bubble jet” is a registered trademark)) that ejects ink using thermal expansion of a material by an electrothermal transducer.

  In the head 10 having such a configuration, the nozzle plate 11 is provided with a coating 114 formed for the purpose of imparting liquid repellency. Thus, when ink droplets are ejected from the nozzle holes 111, it is possible to reliably prevent ink droplets from remaining around the nozzle holes 111. As a result, the ink droplets ejected from the nozzle hole 111 can be reliably landed on the target area.

As described above, the bonding method, the bonded body, the droplet discharge head, and the droplet discharge 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 bonding method of the present invention, one or more optional steps may be added as necessary.
Moreover, although the said embodiment demonstrated the method to join two to-be-adhered bodies (a 1st to-be-adhered body and a 2nd to-be-adhered body), when joining three or more to-be-adhered bodies, this You may apply the joining method of invention.

Next, specific examples of the present invention will be described.
1. Manufacture of joined body (Example 1)
First, a single crystal silicon substrate having a length of 20 mm × width of 20 mm × an average thickness of 1 mm is prepared as the first base material, and a glass substrate of length 20 mm × width 20 mm × average thickness of 1 mm is prepared as the second base material. did.

Next, both the silicon substrate and the glass substrate were accommodated in the chamber 101 of the plasma polymerization apparatus 100 shown in FIG. 1, and surface treatment with oxygen plasma was performed.
Next, a plasma polymerization film having an average thickness of 200 nm was formed on each surface of the silicon substrate and the glass substrate subjected to surface treatment. As a result, a first adherend and a second adherend were obtained. The film forming conditions are as shown below.

<Film formation conditions>
-Source gas composition: Octamethyltrisiloxane-Source gas flow rate: 50 sccm
Carrier gas composition: Argon Carrier gas flow rate: 100 sccm
・ High frequency power output: 100W
-Chamber pressure: 1 Pa (low vacuum)
・ Processing time: 15 minutes ・ Substrate temperature: 20 ° C.

Then, the 1st to-be-adhered body and the 2nd to-be-adhered body were piled up so that each obtained plasma polymerization film might contact | adhere. Thereby, a temporary joined body was obtained.
Next, the obtained temporary joined body was irradiated with ultraviolet rays under the following conditions. Thereby, adhesiveness was expressed in each plasma polymerization film in a temporary joined object, and a joined object was obtained. In addition, the area | region which irradiated the ultraviolet-ray was made into the frame-shaped area | region of width 3mm of the peripheral part of a temporary joining body.

<Ultraviolet irradiation conditions>
-Atmospheric gas composition: Air (air)
・ Atmospheric gas temperature: 20 ℃
・ Atmospheric gas pressure: Atmospheric pressure (100 kPa)
UV wavelength: 172 nm
-Ultraviolet irradiation time: 5 minutes Next, the obtained joined body was heated at 80 ° C while being pressurized at 3 MPa, and maintained for 15 minutes. Thereby, the joint strength of the joined body was improved.

(Example 2)
A joined body was obtained in the same manner as in Example 1 except that the heating temperature was changed from 80 ° C to 25 ° C.
(Example 3)
While changing the constituent material of a 2nd base material to the material shown in Table 1, it replaced with the method of irradiating an ultraviolet-ray, and it was made to heat the temporary joining body on the conditions shown below, and said Example 1 and A joined body was obtained in the same manner. In addition, the heated area | region was made into the frame-shaped area | region of width 3mm of the peripheral part of a temporary joining body.
<Heating conditions>
・ Heat source: Heater ・ Heating temperature: 80 ℃
・ Heating time: 5 minutes ・ Heating atmosphere: air (air)

Example 4
First, a single crystal silicon substrate having a length of 20 mm × width of 20 mm × average thickness of 1 mm is prepared as a first base material, and a stainless steel substrate of length 20 mm × width 20 mm × average thickness of 1 mm is prepared as a second base material. Prepared.
Next, the silicon substrate was accommodated in the chamber 101 of the plasma polymerization apparatus 100 shown in FIG. 1, and surface treatment with oxygen plasma was performed.

Next, a plasma polymerization film having an average thickness of 200 nm was formed on the surface subjected to the surface treatment. As a result, a first adherend was obtained. The film forming conditions are the same as in Example 1.
On the other hand, one surface of the glass substrate (second adherend) was subjected to surface treatment with oxygen plasma.
Subsequently, the first adherend and the second adherend were overlapped so that the plasma polymerized film and the surface of the glass substrate subjected to the oxygen plasma treatment were in close contact with each other. Thereby, a temporary joined body was obtained.

Next, the temporary joined body obtained on the conditions shown below was heated. Thereby, adhesiveness was expressed in the plasma polymerization film in the temporary joined body, and the joined body was obtained. In addition, the heated area | region was made into the frame-shaped area | region of width 3mm of the peripheral part of a temporary joining body.
<Heating conditions>
・ Heat source: Heater ・ Heating temperature: 80 ℃
・ Heating time: 5 minutes ・ Heating atmosphere: air (air)

(Example 5)
A joined body was obtained in the same manner as in Example 4 except that the heating temperature was changed from 80 ° C to 25 ° C.
(Example 6)
A joined body was obtained in the same manner as in Example 4 except that the constituent material of the second base material was changed to the material shown in Table 1.

(Examples 7 to 9)
A joined body was obtained in the same manner as in Example 1 except that the constituent material of the first base material and the constituent material of the second base material were changed to the materials shown in Table 1, respectively.
(Example 10)
A joined body was obtained in the same manner as in Example 4 except that the constituent material of the first base material was changed to the material shown in Table 1.

(Examples 11 to 12)
A joined body was obtained in the same manner as in Example 1 except that the constituent material of the first base material and the constituent material of the second base material were changed to the materials shown in Table 1, respectively.
(Example 13)
A joined body was obtained in the same manner as in Example 4 except that the constituent material of the first base material and the constituent material of the second base material were changed to the materials shown in Table 1.
(Examples 14 to 16)
A joined body was obtained in the same manner as in Examples 1, 3, and 4 except that the raw material gas was changed to the gas having the composition shown in Table 1 and the composition of the plasma polymerized film was changed.

(Comparative Examples 1-3)
A joined body was obtained in the same manner as in Examples 1, 3 and 4 except that the substrates were bonded with an epoxy adhesive.
(Reference Example 1)
A joined body was obtained in the same manner as in Example 1 except that the region irradiated with ultraviolet rays was changed and the entire temporary joined body was irradiated with ultraviolet rays.
(Reference Examples 2-3)
A joined body was obtained in the same manner as in Examples 3 and 4 except that the region to be heated was changed and the entire temporary joined body was heated.

2. 2. Evaluation of Bonded Body 2.1 Evaluation of Bonding Strength (Split Strength) The bonding strength was measured for each of the bonded bodies obtained in each Example, each Comparative Example, and each Reference Example.
As a result, the joint strength of the joined body obtained in each example was lower than the joint strength of the joined body obtained in each reference example. From this, it is clear that the joining strength can be adjusted by selecting whether the joining region is part or all of the joining surface, that is, by changing the area of the joining part. became.
Moreover, the joint strength of the joined body obtained in each Example was larger than the joint strength of the joined body obtained in each Comparative Example.

2.2 Evaluation of dimensional accuracy The dimensional accuracy in the thickness direction was measured for each of the joined bodies obtained in each Example, each Comparative Example, and each Reference Example.
The measurement of the dimensional accuracy was performed by measuring the thickness of each corner of the square joined body and calculating the difference between the maximum value and the minimum value of the thicknesses at the four locations. This difference was evaluated according to the following criteria.
<Evaluation criteria for dimensional accuracy>
○: Less than 10 μm ×: 10 μm or more

2.3 Evaluation of chemical resistance The joined bodies obtained in each Example, each Comparative Example and each Reference Example were applied to an ink for inkjet printer (HQ4, manufactured by Epson Corporation) maintained at 80 ° C. under the following conditions. Soaked for a week. Thereafter, each base material was peeled off, and it was confirmed whether or not ink entered the bonding interface. The results were evaluated according to the following criteria.

<Evaluation criteria for chemical resistance>
◎: Not penetrated at all ○: Slightly penetrated into the corner △: Infiltrated along the edge ×: Intruded inside

2.4 Evaluation of Shape Change About the joined body obtained in each Example, each comparative example, and each reference example, the shape change before and after joining of each joined body was measured.
Specifically, the warpage amount of the joined body was measured before and after joining and evaluated according to the following criteria.

<Evaluation criteria for warpage>
◎: The amount of warpage hardly changed before and after joining. ○: The amount of warpage slightly changed before and after joining. △: The amount of warpage slightly changed before and after joining. Table 1 shows the evaluation results of 2.2 to 2.4.

As is apparent from Table 1, the joined bodies obtained in each Example exhibited superior characteristics compared to the joined bodies obtained in each Comparative Example in both items of dimensional accuracy and chemical resistance. .
Moreover, the joined body obtained in each example had a smaller change in warpage than the joined body obtained in each reference example.
Moreover, in Example 5, since the heating temperature was set lower than that in Example 4, it was possible to suppress a change in the amount of warpage of the obtained joined body.
From the above, it has been clarified that the joined bodies obtained in the respective examples exhibit excellent characteristics in any of the items of joining strength, dimensional accuracy, chemical resistance and warpage amount.

It is a longitudinal cross-sectional view which shows typically the plasma polymerization apparatus used for the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 1st Embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 1st Embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 2nd Embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 2nd Embodiment of the joining method of this invention. It is a figure (perspective view) which shows the other structural example of the conjugate | zygote concerning 2nd Embodiment. It is a figure (longitudinal section) for explaining a 3rd embodiment of the joining method of the present invention. It is a figure (longitudinal section) for explaining a 3rd embodiment of the joining method of the present invention. It is a figure (longitudinal sectional view) for demonstrating 4th Embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 4th Embodiment of the joining method of this invention. It is a disassembled perspective view which shows the inkjet recording head (droplet discharge head) obtained by applying the conjugate | zygote of this invention. It is sectional drawing which shows the structure of the principal part of the inkjet recording head shown in FIG. It is the schematic which shows embodiment of an inkjet printer provided with the inkjet recording head shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Bonded body 21 ... 1st base material 22 ... 2nd base material 23, 24 ... Joining surface 3, 301, 302, 3a, 3b ... Plasma polymerized film 31, 303, 304 ... Surface 310, 310a, 310b ... predetermined area 3c ... gap 41 ... first adherend 42 ... second adherend 5 ... temporary joined body 6 ... mask 61 ... window part 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 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 19 ... Piping 195 ... Diffusion plate 10 ... Inkjet recording head 11 ... Nozzle plate 111 ... Nozzle hole 114 ... Coating 12 ... Ink chamber substrate 121 ... Ink chamber 122 ... Side wall 123 ... Reservoir chamber 124 …… Supply port 13 …… Vibration plate 131 …… Communication hole 14 …… Piezoelectric element 141 …… Upper electrode 142 …… Lower electrode 143 …… Piezoelectric layer 16 …… Substrate 161 …… Concavity 162 …… Step 17 …… Head body 9 ...... Inkjet printer 92 ...... Device body 921 ...... Tray 922 ...... Discharge outlet 93 …… Head unit 931 ...... Ink cartridge 932 …… Carriage 94 …… Printing device 941 …… Carriage motor 942 …… Reciprocating Moving mechanism 943 …… Carriage guide shaft 944 …… Timing belt 95 …… Paper feeding device 951 …… Feeding motor 952 …… Feeding roller 952a …… Following roller 952b …… Drive roller 96 …… Control unit 97 …… Operation panel P …… Recording paper

Claims (29)

An adherend preparation step of preparing a first adherend comprising a plasma polymerized film on a substrate and a second adherend;
The first adherend and the second adherend are overlapped and temporarily bonded so that the plasma polymerized film of the first adherend and the second adherend are in close contact with each other. A laminating process for obtaining a body;
In the plasma polymerized film, by applying energy to a predetermined region, the plasma polymerized film and the second adherend are joined in the predetermined region to obtain an joined body. And a bonding method characterized by comprising: An adherend preparation step of preparing a first adherend comprising a substrate and a plasma polymerized film provided in a predetermined region on the substrate; and a second adherend;
The first adherend and the second adherend are overlapped and temporarily bonded so that the plasma polymerized film of the first adherend and the second adherend are in close contact with each other. A laminating process for obtaining a body;
An energy applying step of joining the plasma polymerized film and the second adherend in the predetermined region by applying energy to the plasma polymerized film to obtain a joined body. Method. A hydroxyl group is present on the surface of the second adherend that is in close contact with the plasma polymerization film,
In the laminating step, the first adherend and the second adherend are overlapped so that the plasma polymerized film and the surface of the second adherend on which the hydroxyl group exists are in close contact with each other. The joining method according to claim 1 or 2, which is combined. The surface of the second adherend that is in close contact with the plasma polymerization film is covered with an oxide film,
In the laminating step, the first adherend and the second adherend are adhered so that the plasma polymerized film and the surface of the second adherend covered with the oxide film are in close contact with each other. The joining method according to any one of claims 1 to 3, wherein the two are superposed. The second adherend is provided with a plasma polymerized film on a substrate,
In the laminating step, the plasma polymerized film of the first adherend and the plasma polymerized film of the second adherend are superposed so that they are in close contact with each other,
5. The energy is applied to at least a portion where the plasma polymerized film of the first adherend and the plasma polymerized film of the second adherend overlap each other in the energy applying step. The joining method according to the above.   The bonding method according to claim 5, wherein the second adherend includes a base material and a plasma polymerization film provided in a predetermined region on the base material.   The joining method according to claim 5 or 6, wherein the plasma polymerized film of the first adherend and the plasma polymerized film of the second adherend are made of the same kind of material.   The joining method according to any one of claims 1 to 7, wherein the plasma polymerized film is composed mainly of polyorganosiloxane or organometallic polymer.   The joining method according to claim 8, wherein the polyorganosiloxane is mainly composed of a polymer of octamethyltrisiloxane.   The bonding method according to claim 8, wherein the organometallic polymer is mainly composed of a polymer of trimethylgallium or trimethylaluminum.   The bonding method according to claim 1, wherein an average thickness of the plasma polymerized film is 1 to 1000 nm.   The energy application in the energy application step is performed by at least one of a method of heating the temporary joined body and a method of applying pressure to the temporary joined body. The joining method described in 1.   The joining method according to claim 12, wherein the heating temperature is 25 to 100 ° C.   The joining method according to claim 12 or 13, wherein the compressive force is 0.2 to 10 MPa. At least one of the base material provided in the first adherend and the base material provided in the second adherend has energy ray permeability,
The joining method according to any one of claims 1 to 14, wherein the application of the energy in the energy applying step is performed by a method of irradiating the energy beam from the side of the permeable base material of the temporary joined body. At least one of the base material provided in the first adherend and the base material provided in the second adherend has translucency,
The bonding method according to claim 1, wherein the energy application in the energy application process is performed by a method of irradiating ultraviolet rays from the translucent substrate side of the temporary bonded body.   The bonding method according to claim 16, wherein the wavelength of the ultraviolet light is 150 to 300 nm.   The bonding method according to claim 16 or 17, wherein the energy beam irradiation is performed in an air atmosphere.   The joining method according to claim 1, further comprising a step of heating the joined body after the energy applying step.   The joining method according to claim 19, wherein the heating temperature is 25 to 100 ° C.   The joining method according to any one of claims 1 to 20, further comprising a step of pressurizing the joined body after the energy applying step.   The joining method according to claim 21, wherein the pressure when the joined body is pressurized is 0.2 to 10 MPa.   The first adherend is formed in advance by subjecting the base material to a surface treatment for improving adhesion with the plasma polymerized film, and then forming the plasma polymerized film in the surface-treated region. The joining method according to claim 1, wherein the joining method is one.   The bonding method according to claim 23, wherein the surface treatment is a plasma treatment.   The joining method according to any one of claims 1 to 24, wherein the base material provided in the first adherend and the base material provided in the second adherend have different rigidity.   A bonded body, wherein two base materials are bonded by the bonding method according to claim 1.   27. The joined body according to claim 26, wherein a joining strength between the two base materials is 5 MPa or more.   A droplet discharge head comprising the joined body according to claim 26 or 27.   A droplet discharge apparatus comprising the droplet discharge head according to claim 28.

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