JP2013060530A - Bonding method and bonded body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bonding method that can bond, even if a substrate mainly formed of an aramid-based resin is used as a second substrate on which no bonding film is formed, a first substrate with a bonding film formed thereon and the second substrate together with sufficient bonding strength, and to provide a bonded body bonded by using the bonding method.SOLUTION: The bonding method includes: a step for forming a liquid film 30 by supplying liquid material 35 containing a silicone material to a substrate 21; a step for forming a bonding film 3 on the substrate 21 by drying and/or solidifying the liquid film 30; a step for bringing a polar solvent into contact with a surface of a substrate 22 mainly formed of an aramid-based resin after being subjected to a hydroxyl group introduction treatment; a step for developing adhesiveness on and around the surface of the substrate by applying energy to the bonded film 3; and a step for obtaining a bonded body 1 by bringing the substrate 21 and the substrate 22 into contact with each other through the bonding film 3.

Description

  The present invention relates to a joining method and a joined body.

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 generally exhibits excellent adhesiveness regardless of the material of the members to be joined. 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-based 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 members are bonded together by curing (solidifying) the adhesive by the action of heat or light.

However, the joining using 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 material 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. A bonding method has been proposed in which a first base material and a second base material are bonded to each other through a bonding film formed using a liquid material containing a silicone material (see, for example, Patent Document 2). .

  In this bonding method, first, a bonding film is formed on the first base material using this liquid material, and then, after applying energy to the bonding film, adhesiveness is expressed in the vicinity of the surface. The first base material and the second base material are joined with this adhesiveness. However, according to the study of the present inventors, when an aramid film composed mainly of an aramid resin is used as the second base material on which the bonding film is not formed, peeling is performed between the aramid film and the bonding film. It has been found that sufficient adhesive strength cannot be obtained between them.

JP-A-5-82404 JP 2010-95594 A

  The object of the present invention is to form the second base material and the bonding film even when the second base material on which the bonding film is not formed is composed of an aramid resin as a main material. Another object of the present invention is to provide a bonding method capable of bonding the first base material with sufficient bonding strength, and a bonded body bonded by the bonding method.

Such an object is achieved by the present invention described below.
The bonding method of the present invention includes a step of forming a liquid film by supplying a liquid material containing a silicone material to the first substrate,
Drying and / or curing the liquid film to form a bonding film on the first substrate;
After the surface of the second substrate composed mainly of an aramid resin is subjected to a hydroxyl group introduction treatment for introducing a hydroxyl group, a polar solvent is brought into contact with the surface of the second substrate subjected to the hydroxyl group introduction treatment A process of
A step of expressing adhesiveness on the surface of the bonding film and in the vicinity of the surface by applying energy to the bonding film formed on the first substrate;
The first base material and the second base material are brought into contact with each other through the bonding film expressing the adhesiveness, and the first base material and the second base material are interposed through the bonding film. And a step of obtaining a joined joined body.
Thereby, even if it is a case where the thing comprised as a main material is an aramid-type resin as a 2nd base material in which a joining film | membrane is not formed, this 2nd base material and the 1st in which the joining film | membrane was formed Can be bonded with sufficient bonding strength.

［式中、各Ｒ^１は、それぞれ独立して、メチル基またはフェニル基を表し、Ｘはシロキサン残基を表す。］
これにより、得られる接合膜を、特に膜強度に優れたものとすることができる。 In the bonding method of the present invention, the silicone material has a unit structure represented by the following chemical formula (1) at the branch portion, and at least one of the following chemical formula (2) and the following chemical formula (3) at the connecting portion. It has a unit structure represented and has a branched polyorganosiloxane skeleton having a unit structure represented by at least one of the following chemical formula (4) and the following chemical formula (5) at the terminal portion. preferable.

[Wherein, each R ¹ independently represents a methyl group or a phenyl group, and X represents a siloxane residue. ]
Thereby, the obtained bonding film can be made particularly excellent in film strength.

In the bonding method of the present invention, the silicone material has a branched polyorganosiloxane skeleton, and a polyester resin obtained by an esterification reaction of trimethylolpropane and terephthalic acid undergoes a dehydration condensation reaction. It is preferable that it is a polyester-modified silicone material obtained in this way.
As a result, the bonding film exhibits particularly excellent film strength.

In the bonding method of the present invention, it is preferable that the silicone material is an epoxy-modified silicone material obtained by an addition reaction of an epoxy resin with the branched polyorganosiloxane skeleton.
As a result, the bonding film exhibits particularly excellent film strength.
In the bonding method of the present invention, it is preferable that the hydroxyl group introduction treatment for the second base material is at least one of plasma treatment and corona discharge treatment.
Thereby, a hydroxyl group can be selectively introduced into the surface of the second substrate.

In the bonding method of the present invention, the polar solvent is preferably water or alcohols.
Thereby, the cut aramid resin can be reliably removed from the second substrate together with the polar solvent.

In the joining method of the present invention, it is preferable that the first base material is composed of a metal-based material as a main material.
The first base material composed of such a metal material has a surface roughness curve with a maximum height Rz (specified in JIS B 0651), which is usually 100 nm or more and has large surface irregularities. Therefore, the surface of the obtained bonding film can be flattened by forming the bonding film after forming the liquid film using the liquid material as in the present invention.
The joined body of the present invention is characterized in that the first base material and the second base material are joined through the joining film by the joining method of the present invention.
Thereby, a highly reliable joined body is obtained.

It is a figure (longitudinal sectional view) for demonstrating embodiment of the joining method of this invention. It is a figure (longitudinal sectional view) for demonstrating 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 the schematic which shows embodiment of an inkjet printer provided with the inkjet recording head shown in FIG.

Hereinafter, a joining method and a joined object of the present invention are explained in detail based on a suitable embodiment shown in an accompanying drawing.
<Join method>
The bonding method of the present invention includes: [1] preparing a first substrate 21 and supplying a liquid material containing a silicone material to the first substrate 21 to form the liquid coating 30; 2) drying and / or curing the liquid film to form the bonding film 3 on the first substrate 21, and [3] the second substrate 22 composed mainly of an aramid resin. A step of bringing a polar solvent into contact with the surface of the second base material subjected to the hydroxyl group introduction treatment after the hydroxyl group introduction treatment for introducing a hydroxyl group on the surface; [4] formed on the first base material 21 Applying energy to the bonding film 3 to develop adhesiveness on the surface of the bonding film 3 and in the vicinity of the surface, and [5] the first substrate 21 and the first substrate through the bonding film 3 exhibiting adhesiveness. Two base materials 22 are brought into contact with each other, and the first base material 21 and the second base material 22 are And a step of obtaining a bonded body 1 which is bonded via the Gomaku 3.

Hereinafter, the joining method of the present invention will be described in detail for each step.
1 and 2 are views (longitudinal sectional views) for explaining an embodiment of the joining method of the present invention. In the following description, the upper side in FIGS. 1 and 2 is referred to as “upper” and the lower side is referred to as “lower”.
[1] First, the first base material 21 is prepared, and the liquid film 30 is formed by supplying a liquid material containing a silicone material to the first base material 21.

[1-1] First, the first base material 21 is prepared.
Each constituent material of the first substrate 21 is not particularly limited, but polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-acrylic acid ester copolymer, ethylene-acrylic acid copolymer, polybutene-1, ethylene. -Polyolefin such as vinyl acetate copolymer (EVA), cyclic polyolefin, modified polyolefin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, polyimide, polyamideimide, polycarbonate, poly- (4-methylpentene-1), ionomer , Acrylic resin, polymethyl methacrylate (PMMA), acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrene copolymer, polyoxymethylene, poly Polyesters such as vinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH), polyethylene terephthalate (PET), polyethylene naphthalate, polybutylene terephthalate (PBT), polycyclohexane terephthalate (PCT), polyether, polyether ketone (PEK), polyetheretherketone (PEEK), polyetherimide, polyacetal (POM), polyphenylene oxide, modified polyphenylene oxide, polysulfone, polyethersulfone, polyphenylene sulfide (PPS), polyarylate, aromatic polyester (liquid crystal polymer ), Polytetrafluoroethylene, polyvinylidene fluoride, other fluororesins, styrene, polyolefin, polyvinyl chloride , Polyurethane, polyester, polyamide, polybutadiene, trans polyisoprene, fluoro rubber, chlorinated polyethylene, and other thermoplastic elastomers, epoxy resins, phenol resins, urea resins, melamine resins, unsaturated polyesters, silicones Resin, polyurethane, etc., or a resin-based material such as a copolymer, blend, polymer alloy, etc., such as Fe, Ni, Co, Cr, Mn, Zn, Pt, Au, Ag, Cu, Pd, Al, Metals such as W, Ti, V, Mo, Nb, Zr, Pr, Nd, Sm, or alloys containing these metals, metals such as carbon steel, stainless steel, indium tin oxide (ITO), gallium arsenide Materials, silicon materials such as single crystal silicon, polycrystalline silicon, amorphous silicon, silicate glass Glass (quartz glass), alkali silicate glass, soda lime glass, potash lime glass, lead (alkali) glass, barium glass, borosilicate glass, alumina, zirconia, MgAl ₂ O ₄ , ferrite, nitriding Ceramic material such as silicon, aluminum nitride, boron nitride, titanium nitride, silicon carbide, boron carbide, titanium carbide, tungsten carbide, carbon-based material such as graphite, or one or more of these materials The composite material etc. which were combined are mentioned. Among these, it is preferable that the liquid coating 30 is formed on the first base material 21 composed mainly of a metal-based material (especially stainless steel). The first base member 21 made of such a material has a maximum roughness Rz (specified in JIS B 0651) of the roughness curve of the joint surface 23, which is usually 100 nm or more and has large surface irregularities. Therefore, by forming the liquid film 30 using the liquid material 35 as described above and then forming the bonding film 3 in a later step, the surface 32 of the obtained bonding film 3 is flattened. Can be.

Moreover, the shape of the 1st base material 21 should just be a shape which has the surface which supports the bonding film 3, for example, is made into plate shape (layer shape), block shape (block shape), rod shape, etc.
In the present embodiment, as shown in FIGS. 1 and 2, the first base material 21 has a plate shape.
In this case, the average thickness of the first base material 21 is not particularly limited, but is preferably about 0.01 to 10 mm, and more preferably about 0.1 to 3 mm.

  If necessary, the bonding surface 23 of the first base material 21 is subjected to a surface treatment for improving the adhesion with the bonding film 3 to be formed prior to supplying the liquid material 35. Thereby, the bonding surface 23 is cleaned and activated, and the bonding film 3 easily acts on the bonding surface 23 chemically. As a result, when the bonding film 3 is formed on the bonding surface 23 in a process described later, the bonding strength between the bonding surface 23 and the bonding 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.
Moreover, the 1st base material 21 may give the surface the plating process like Ni plating, the passivation process like a chromate process, or the nitriding process.

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 or ultraviolet irradiation treatment. As a result, the bonding strength between the bonding surface 23 and the bonding film 3 can be particularly increased.

In addition, depending on the constituent material of the first base material 21, the bonding strength with the bonding 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 materials, various silicon materials, various glass 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 more hydroxyl groups are bonded (exposed) 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 bonding film 3 are not subjected to the surface treatment as described above. Bonding strength can be increased.

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 for forming the bonding film 3 may be made of the material as described above. That's fine.
Instead of the surface treatment, an intermediate layer may be formed in advance on the bonding surface 23 of the first base material 21.
The intermediate layer may have any function. For example, a layer having a function of improving adhesion to the bonding film 3, a cushioning function (buffer function), a function of reducing stress concentration, and the like are preferable. By forming the bonding film 3 on such an intermediate layer, a highly reliable bonded body 1 can be finally 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 made of these materials, the intermediate layer made of an oxide-based material can particularly increase the bonding strength between the first base material 21 and the bonding film 3. it can.

[1-2] Next, a liquid material 35 containing a silicone material is supplied onto the bonding surface 23 of the first base material 21. Thereby, as shown to Fig.1 (a), the liquid film 30 is formed on the 1st base material 21. FIG.
Here, examples of a method for applying the liquid material 35 to the bonding surface 23 include an immersion method, a droplet discharge method (for example, an ink jet method), a spin coating method, a doctor blade method, a bar coating method, and a brush coating method. Of these, one or two or more of these can be used in combination.

  The liquid material 35 contains a silicone material. However, when the silicone material alone is liquid and has a desired viscosity range, the silicone material can be used as the liquid material 35 as it is. When the silicone material alone forms a solid or high-viscosity liquid, a solution or dispersion of the silicone material can be used as the liquid material 35.

  Examples of the solvent or dispersion medium for dissolving or dispersing the silicone material include inorganic solvents such as ammonia, water, hydrogen peroxide, carbon tetrachloride, and ethylene carbonate, and ketone solvents such as methyl ethyl ketone (MEK) and acetone. Alcohol solvents such as methanol, ethanol and isobutanol, ether solvents such as diethyl ether and diisopropyl ether, cellosolve solvents such as methyl cellosolve, aliphatic hydrocarbon solvents such as hexane and pentane, toluene, xylene, benzene, etc. Aromatic hydrocarbon solvents, aromatic heterocyclic compound solvents such as pyridine, pyrazine, furan, amide solvents such as N, N-dimethylformamide (DMF), halogen compound solvents such as dichloromethane and chloroform, ethyl acetate Esters such as methyl acetate Various organic solvents such as solvents, sulfur compound solvents such as dimethyl sulfoxide (DMSO), sulfolane, nitrile solvents such as acetonitrile, propionitrile, acrylonitrile, organic acid solvents such as formic acid, trifluoroacetic acid, or the like A mixed solvent containing can be used.

In the next step [2], when the liquid film 30 is cured by dehydrating condensation between hydroxyl groups contained in the silicone material, a catalyst for promoting the dehydrating condensation reaction is contained in the liquid material 35. It may be added. The catalyst is not particularly limited. For example, a titanium-based catalyst such as tetrabutyl orthotitanate and tetraisopropyl orthotitanate, an aluminum-based catalyst such as aluminum tris (acetylacetonate), and phosphoric acid, metaphosphoric acid, Examples include phosphoric acid-based catalysts such as polyphosphoric acid.
The silicone material is contained in the liquid material 35 and becomes the main material of the bonding film 3 formed by drying and / or curing the liquid material 35 in the next step [2].

  In the following, the liquid film 30 (liquid material 35) provided on the first substrate 21 is dried and / or cured, that is, the silicone material contained in the liquid film 30 (liquid material 35) is used. When the liquid film 30 (liquid material 35) contains a solvent or dispersion medium, the liquid film 30 (liquid material 35) is simply dried by the solvent removal or dedispersion medium. 30 (drying / curing of liquid material 35) ".

  Here, the “silicone material” is not particularly limited, but in the present invention, it is contained in the liquid material 35 and is formed by drying and curing the liquid material 35 in the next step [3]. 3 has a unit structure represented by the following chemical formula (1) in the branched portion, and is represented by at least one of the following chemical formula (2) and the following chemical formula (3) in the connecting portion. Those having a unit structure and having a branched polyorganosiloxane skeleton having a unit structure represented by at least one of the following chemical formula (4) and the following chemical formula (5) at the terminal portion are preferably used.

［式中、各Ｒ^１は、それぞれ独立して、メチル基またはフェニル基を表し、Ｘはシロキサン残基を表す。］

[Wherein, each R ¹ independently represents a methyl group or a phenyl group, and X represents a siloxane residue. ]

The siloxane residue is a substituent that is bonded to a silicon atom of an adjacent structural unit through an oxygen atom and forms a siloxane bond. Specifically, it has an —O— (Si) structure (Si is a silicon atom of an adjacent structural unit).
Since the silicone material, that is, the polyorganosiloxane skeleton is thus branched, in the next step [2], the branched chains of this compound contained in the liquid material 35 are entangled with each other. Since the bonding film 3 is formed, the obtained bonding film 3 is particularly excellent in film strength.

Further, the molecular weight of the silicone material is preferably about 1 × 10 ⁴ to 1 × 10 ^6, more preferably about 1 × 10 ⁵ to 1 × 10 ⁶ . By setting the molecular weight within such a range, the viscosity of the liquid material 35 can be set relatively easily within the above-described range.
Further, the silicone material has a silanol by forming a unit structure represented by the general formula (2), the general formula (4), or the general formula (5) in the compound, that is, at the connecting portion or the terminal portion. It has a plurality of groups. Thereby, in the next step [2], when the liquid film 30 is dried and cured to obtain the bonding film 3, the hydroxyl groups contained in the silanol groups remaining in the silicone material are bonded to each other and thus obtained. The film strength of the bonding film 3 is further improved.

  Further, as described above, when the first base material 21 having a hydroxyl group exposed from the joint surface (surface) 23 is used, the hydroxyl group remaining in the silicone material, Since the hydroxyl group of the base material 21 is bonded, the silicone material can be bonded to the first base material 21 not only by physical bonding but also by chemical bonding. As a result, the bonding film 3 is firmly bonded to the bonding surface 23 of the first base material 21.

In the compound, the silicone material has a unit structure represented by the general formula (1), the general formula (2), and the general formula (4), and at least one of R ¹ is phenyl A group is preferred. Thereby, since the reactivity of a silanol group improves more, the coupling | bonding of the hydroxyl groups which an adjacent silicone material has comes to be performed more smoothly. Further, by adopting a configuration in which the bonding film 3 includes a phenyl group, there is also an advantage that the bonding film 3 to be formed can be more excellent in film strength.

Furthermore, the above-mentioned general formula (1), R ¹ is not a phenyl group of the above general formula (2) and the general formula (4) R ¹ in which the unit structure represented comprises at has a methyl group. A compound in which the group R ¹ is a methyl group is relatively easily available and inexpensive, and the methyl group is easily cleaved by applying energy to the bonding film 3 in the subsequent step [4]. As a result, the bonding film 3 can reliably exhibit adhesiveness.

  Further, the silicone material is a material having a relatively high flexibility. Therefore, in the post-process [5], the heat generated between the base materials 21 and 22 when the joined body 1 is obtained by joining the second base material 22 to the first base material 21 via the bonding film 3. The stress accompanying expansion can be surely relieved. Thereby, in the bonded body 1 finally obtained, it is possible to reliably prevent peeling at the interface between the base materials 21 and 22 and the bonding film 3.

Furthermore, since the silicone material is excellent in chemical resistance, it can be effectively used for joining members that are exposed to chemicals and the like for a long time. Specifically, for example, when manufacturing a droplet discharge head of an industrial inkjet printer that uses an organic ink that easily erodes a resin material, if the bonding film 3 is used for bonding, the durability can be ensured. Can be improved. Moreover, since the said silicone material is excellent also in heat resistance, it can be used effectively also at the time of joining of the member exposed to high temperature.
The silicone material may be a “polyester-modified silicone material” obtained by a dehydration condensation reaction of a polyester resin with the above-described branched polyorganosiloxane skeleton.

In the present specification, “polyester resin” means a compound obtained by an esterification reaction of trimethylolpropane and terephthalic acid, and preferably has at least two hydroxyl groups in one molecule. Used.
When such a polyester resin is subjected to a condensation reaction with the above-described silicone material, a hydroxyl group of the polyester resin and a silanol group (hydroxyl group) of the silicone material undergo a dehydration condensation reaction, whereby the polyester resin is linked to the silicone material. A polyester-modified silicone material is obtained.

In addition, each content at the time of carrying out esterification reaction of a terephthalic acid and a trimethylol propane is set so that it may become more than the hydroxyl group which a trimethylol propane has rather than the carboxyl group which a terephthalic acid has. Thereby, the synthesized polyester resin has at least two hydroxyl groups in one molecule.
Considering the above, examples of the polyester resin obtained from terephthalic acid and trimethylolpropane include compounds represented by the following general formula (6).

Such a polyester resin contains a phenylene group derived from terephthalic acid in its molecule. When the bonding film 3 is formed using the polyester-modified silicone material containing the polyester resin having such a structure, the bonding film 3 formed has a particularly excellent film strength due to the fact that the polyester resin contains a phenylene group. Will be demonstrated.
Further, when such a polyester resin is provided in the polyester-modified silicone material, the polyester-modified silicone material usually exists in a state where the polyester resin is exposed from the polyorganosiloxane skeleton having a spiral structure. Will be. Therefore, in the next step [2], when the liquid coating 30 is dried and cured to obtain the bonding film 3, the chance that the polyester resins provided in the adjacent polyester-modified silicone materials come into contact with each other increases. As a result, in the adjacent polyester-modified silicone material, the polyester resins are entangled with each other, or the hydroxyl groups included in these are dehydrated and condensed and chemically bonded, so that the strength of the bonding film 3 to be obtained is more reliable. Can be improved.

  Further, as described above, when the first base member 21 having a hydroxyl group exposed from the joint surface (surface) 23 is used, the hydroxyl group remaining in the polyester resin, Since the hydroxyl group provided in the substrate 21 is bonded by a dehydration condensation reaction, the polyester-modified silicone material can be bonded to the first substrate 21 not only by physical bonding but also by chemical bonding. As a result, the bonding film 3 is firmly bonded to the bonding surface 23 of the first base material 21. Furthermore, since a hydrogen bond is generated between the ketone group included in the polyester resin and the hydroxyl group included in the first base material 21, the bonding film 3 is bonded to the bonding surface 23 of the first base material 21 even by such bonding. On the other hand, it will be firmly joined.

The silicone material may be an “epoxy-modified silicone material” obtained by an addition reaction of an epoxy resin with the above-described branched polyorganosiloxane skeleton.
In the present specification, “polyester resin” refers to a compound having an epoxy group at its end, and may be any of a monomer, an oligomer or a polymer having an epoxy group, and at least two in one molecule. Those having an epoxy group are preferably used.

When such an epoxy resin is subjected to an addition reaction with a silicone material, an epoxy group possessed by the epoxy resin and a silanol group (hydroxyl group) possessed by the silicone material undergo an addition reaction, whereby an epoxy resin in which the epoxy resin is linked to the silicone material. A modified silicone material is obtained.
The epoxy resin preferably has a phenylene group in its molecule. When the bonding film 3 is formed using an epoxy-modified silicone material containing an epoxy resin having such a configuration, the bonding film 3 formed has particularly excellent film strength due to the fact that the epoxy resin contains a phenylene group. Will be demonstrated.

  Furthermore, it is preferable that the epoxy resin has a linear structure in its molecular structure. Here, the silicone material to which the epoxy resin is connected usually has a polyorganosiloxane skeleton which is the main skeleton having a helical structure. Therefore, the epoxy resin connected to the silicone material exists in a state where it is exposed (protruded) from the spiral silicone material. Therefore, when the molecular structure of the epoxy resin is linear, in the next step [2], when the liquid film 30 is dried and cured to obtain the bonding film 3, the epoxy included in the adjacent epoxy-modified silicone material is provided. The opportunity for the resins to contact each other can be increased. As a result, in the epoxy-modified silicone material, the epoxy resins are entangled with each other, or the epoxy groups included in these are ring-opening polymerized and chemically bonded to each other. Can be improved.

Further, as described above, when the first base material 21 having a hydroxyl group exposed from the joint surface (surface) 23 is used, the epoxy resin included in the epoxy-modified silicone material is a linear type. Since the reaction rate of the addition reaction between the epoxy group remaining in the epoxy resin and the hydroxyl group included in the first base material 21 is improved, the epoxy-modified silicone material is physically bonded. In addition, the first substrate 21 can be securely bonded by chemical bonding. As a result, the bonding film 3 is more firmly bonded to the bonding surface 23 of the first base material 21.
Considering the above, as the epoxy resin, for example, a bisphenol type epoxy resin is preferably used, and specifically, a bisphenol A type epoxy resin represented by the following general formula (9) can be mentioned.

［式中、ｎは、０または１以上の整数を表す。］

[Wherein n represents 0 or an integer of 1 or more. ]

  In addition, since the bisphenol type epoxy resin is excellent in chemical resistance, the bonding film 3 including the bisphenol type epoxy resin as the epoxy resin is effectively used for bonding members that are exposed to chemicals for a long time. And is suitably applied to joining of members of a droplet discharge head of an industrial inkjet printer, which will be described later. Moreover, since the bisphenol-type epoxy resin is also excellent in heat resistance, it is effectively used for joining members that are exposed to high temperatures.

  The liquid material 35 may contain an additive in addition to the epoxy-modified silicone material. Examples of such additives include various amine compounds and various acid compounds. If such an additive is contained, this additive will be bonded to the epoxy group of the epoxy resin. If this additive contains two or more amino groups or carboxyl groups, It becomes possible to bond the epoxy groups through the agent. Therefore, since the above-described bonding between the epoxy groups is more likely to occur, the film strength of the obtained bonding film 3 can be more reliably improved.

  Among these, the additive is preferably an acid compound containing a carboxyl group. As a result, in the next step [2], the bonding film 3 obtained by drying and curing the liquid film 30 contains a ketone group. Therefore, as described above, when the first base material 21 having a hydroxyl group exposed from the joint surface (surface) 23 is used, the ketone group included in the joint film 3 and the first base material 21 are used. Since a hydrogen bond is generated with the hydroxyl group included in the bonding film 3, the bonding film 3 is more firmly bonded to the bonding surface 23 of the first base material 21 by the bonding.

[2] Next, the liquid material 35 supplied onto the first substrate 21, that is, the liquid coating 30, is dried and / or cured. That is, when the solvent or dispersion medium is contained in the liquid material 35, the liquid film 30 is dried and the silicone material contained in the liquid film 30 is cured. Thereby, as shown in FIG. 1B, the bonding film 3 is formed on the first base material 21.
The method for drying and curing the liquid coating 30 is not particularly limited, but a method for heating the liquid coating 30 is preferably used. According to this method, the liquid film 30 can be easily and reliably dried and cured by a simple method of heating the liquid film 30.

That is, when the liquid film 30 contains a solvent or a dispersion medium by a simple method of heating the liquid film 30, the liquid film 30 is dried by removing the solvent or the dispersion medium from the liquid film 30. In addition, it is possible to cure the dried liquid coating 30 by dehydrating and condensing hydroxyl groups contained in the silicone material.
As described above, when the bonding film 3 is formed by drying and curing the liquid coating 30, the hydroxyl groups contained in the silicone material are chemically coupled to each other by dehydration condensation reaction in the film. The film 3 can have excellent film strength.

Further, at the interface between the bonding film 3 and the first base material 21, a chemical bond is formed between the hydroxyl group contained in the silicone material and the hydroxyl group exposed from the surface of the first base material 21 by a dehydration condensation reaction. Arise.
Further, when a polyester-modified silicone material is used as the silicone material, a hydrogen bond is generated between the ketone group contained in the polyester-modified silicone material and the hydroxyl group exposed from the surface of the first base material 21. The bonding film 3 having excellent adhesion to the substrate 21 can be formed.

The temperature at which the liquid coating 30 is heated is preferably 25 ° C. or higher, and more preferably about 150 to 250 ° C.
The heating time is preferably about 0.5 to 48 hours, and more preferably about 15 to 30 hours.
By drying and curing the liquid coating 30 under such conditions, in the next step [4], it is possible to reliably form the bonding film 3 in which adhesiveness is suitably developed by applying energy.

Furthermore, the atmospheric pressure during heating may be atmospheric pressure, but is preferably reduced pressure. Specifically, the degree of decompression is preferably about 133.3 × 10 ^{−5 to} 1333 Pa (1 × 10 ^{−5 to} 10 Torr), preferably 133.3 × 10 ^{−4 to} 133.3 Pa (1 × 10 ^{-4 to 1} Torr) is more preferable. Thereby, the film density of the bonding film 3 is increased, that is, the bonding film 3 is densified, and the bonding film 3 can have higher film strength.
As described above, the film strength and the like of the formed bonding film 3 can be made desired by appropriately setting the conditions for forming the bonding film 3.

The average thickness of the bonding film 3 is preferably about 10 to 10000 nm, and more preferably about 3000 to 6000 nm. The joining which joined the 1st base material 21 and the 2nd base material 22 by setting the quantity of the liquid material 35 to supply suitably, and making the average thickness of the joining film 3 formed into the said range. It is possible to bond more firmly while preventing the dimensional accuracy of the body from significantly decreasing.
That is, when the average thickness of the bonding film 3 is less than the lower limit, sufficient bonding strength for bonding the first base material 21 and the second base material 22 through the bonding film 3 cannot be obtained. There is a fear. On the other hand, when the average thickness of the bonding film 3 exceeds the upper limit, the dimensional accuracy of the bonded body may be significantly reduced.

  Further, by setting the average thickness of the bonding film 3 in such a range, the bonding film 3 becomes highly elastic to some extent. Therefore, in the post-process [5], the first substrate 21 and the second substrate. Even when particles or the like are attached to the bonding surface 24 of the second base material 22 to be brought into contact with the bonding film 3 when bonding to the bonding film 3, the particles are surrounded by the bonding film 3 and bonded to the bonding film 3. The surface 24 is joined. For this reason, the presence of the particles can accurately suppress or prevent the bonding strength at the interface between the bonding film 3 and the bonding surface 24 from being reduced or the separation from occurring at the interface.

[3] Next, a second base material 22 composed mainly of an aramid resin is prepared, and a hydroxyl group introduction treatment for introducing a hydroxyl group is performed on the second base material 22, followed by a hydroxyl group introduction treatment. A polar solvent is brought into contact with the surface of the second substrate 22 subjected to the above.
[3-1] First, a second substrate 22 composed of an aramid resin as a main material is prepared.

  The aramid resin is not particularly limited. For example, an aromatic dicarboxylic acid component composed of terephthalic acid and / or isophthalic acid, 1,4-phenylenediamine, 1,3-phenylenediamine, and 3,4′-diaminodiphenyl ether And aromatic polyamide derived from at least one aromatic diamine component of 4,4′-diaminodiphenyl ether, and aromatic polyamideimides and copolymers thereof.

The shape of the second base material 22 may be a shape having a surface for supporting the bonding film 3, as in the case of the first base material 21. For example, a plate shape (layer shape) or a block shape (block shape) Shape), rod shape, and the like.
In the present embodiment, as shown in FIGS. 1 and 2, the second base material 22 has a plate shape (film shape). In this case, the average thickness of the second base material 22 is not particularly limited, but is preferably about 0.01 to 10 mm, and more preferably about 0.1 to 3 mm.

[3-2] Next, as shown in FIG. 1C, the second substrate 22 is subjected to a hydroxyl group introduction treatment for introducing hydroxyl groups onto the surface thereof.
By performing this treatment and introducing a hydroxyl group into the bonding surface 24 of the second base material 22, the bonding film 3 formed on the first base material 21 and the second base are formed in this step [5]. When these are superposed so that the bonding surface 24 of the material 22 is in contact, the hydroxyl groups present on the surface 32 of the bonding film 3 and the hydroxyl groups present on the bonding surface 24 of the second substrate 22 are hydrogenated. The bonds attract each other and an attractive force is generated between the hydroxyl groups. It is inferred that the first base material 21 and the second base material 22 are joined by this attractive force.

However, according to the study of the present inventor, when the second base material 22 is composed of an aramid resin as a main material, a hydroxyl group is simply introduced into the surface of the second base material 22. Then, it has been found that the bonding strength between the first base material 21 and the second base material 22 cannot be improved, and peeling occurs at the contact surface between the bonding film 3 and the second base material 22. .
Then, as a result of further earnest studies, the present inventor brought the above-mentioned problem by bringing a polar solvent into contact with the surface of the second substrate 22 after the hydroxyl group introduction treatment to the surface of the second substrate 22. The present inventors have found that the points can be eliminated and have completed the present invention.
In addition, the process of making a polar solvent contact the surface of this 2nd base material 22 is demonstrated in following process [3-3].

  The hydroxyl group introduction treatment is not particularly limited. For example, plasma treatment using oxygen plasma, nitrogen plasma, etc., corona discharge treatment, electron beam irradiation treatment, ultraviolet irradiation treatment, ozone exposure treatment, or a combination thereof. Among them, it is preferable to use at least one of plasma treatment and corona discharge treatment. According to the plasma treatment or the corona discharge treatment, a hydroxyl group can be selectively introduced from the surface of the second substrate 22.

[3-3] Next, as shown in FIG. 1D, a polar solvent is brought into contact with the surface of the second substrate 22.
Here, as described above, when the second base material 22 is composed of an aramid resin as a main material, the second base material 22 is simply used in the step [3-2]. The bonding strength between the first base material 21 and the second base material 22 could not be improved only by introducing a hydroxyl group into the surface. On the other hand, after the hydroxyl group introduction treatment on the surface of the second substrate 22, the first substrate is brought into contact with the surface of the second substrate 22 in this step [3-3]. The bonding strength between the material 21 and the second base material 22 can be improved.

  This is because, due to the characteristics of the second base material composed mainly of an aramid resin, when a hydroxyl group is introduced into the surface in the step [3-2], the aramid resin is cleaved so that a hydroxyl group is formed. Since it is introduced, the aramid resin cleaved at the outermost surface remains. When the second substrate 22 and the bonding film 3 are bonded in this state, the cut aramid resin serves as a starting point (trigger), and peeling occurs at the contact surface between the second substrate 22 and the bonding film 3. Will occur. However, in this step [3-3], the cleaved aramid resin can be removed by bringing a polar solvent into contact with the surface of the second substrate 22, so that the cleaved aramid resin is the starting point. It can be presumed that the bonding strength between the first base material 21 and the second base material 22 is improved because peeling at the contact surface can be accurately suppressed or prevented.

  Examples of polar solvents include water, methanol, ethanol, propanol, butanol, benzyl alcohol, monohydric alcohols such as diethylene glycol monomethyl ether, alcohols such as polyhydric alcohols such as ethylene glycol and glycerin, acetic acid, formic acid, (meth) Carboxylic acids such as acrylic acid, amines such as ethylenediamine and diethylamine, formamide, amides such as N, N-dimethylformamide, phenols such as phenol and p-butylphenol, acetylacetone and diethyl malonate An active methylene compound etc. are mentioned, Among these, it can use combining 1 type (s) or 2 or more types. Especially, as a polar solvent, what has at least 1 sort (s) of water and alcohol as a main component is preferable. Since the cleaved aramid resin is also considered to have a hydroxyl group, by using water or alcohol as a polar solvent, the hydroxyl group can be incorporated into the polar solvent. It can be reliably removed from the substrate 22.

  Further, the method for bringing the polar solvent into contact with the surface of the second base material 22 is not particularly limited, but a method of immersing the second base material 22 in the polar solvent (immersion method), the second base material 22 The method of applying the treatment liquid on the surface (application method), the method of spraying (showering) the treatment liquid on the surface of the second substrate 22 (spraying method), and the like are included. Among these, the dipping method is used. Is preferred. According to the dipping method, a large amount of the second base material 22 can be processed in a short time.

The surface free energy of the second substrate 22 at this time, the h component 10 mJ / ^{m 2} or more, preferably at 40 mJ / ^{m 2} or less, 15 mJ / ^{m 2} or more, 20 mJ / ^{m 2} or less More preferably.
Further, the p component 30 mJ / ^{m 2} or more, preferably at 50 mJ / ^{m 2} or less, 40 mJ / ^{m 2} or more, more preferably 45 mJ / ^{m 2} or less.

  By setting each component of the surface free energy within the above range, the surface of the second base material 22 can be maintained in an appropriate state. Therefore, in the post-process [5], the first base material 21 and The second substrate 22 can be bonded with excellent bonding strength.

  In the present specification, “h component of surface free energy” refers to a hydrogen bond component, “p component of surface free energy” refers to a polar component, and “surface free energy” The “d component” means a dispersion component. Each of these components can be measured, for example, by analyzing the surface free energy of the contact angle measured with a contact angle meter.

[4] Next, energy is applied to the surface 32 of the bonding film 3 formed on the bonding surface 23.
When energy is applied to the bonding film 3, in the bonding film 3, a part of molecular bonds (for example, Si—CH ₃ bond or Si—Phe) near the surface 32 is cut and the surface 32 is activated. Due to the above, adhesion to the second base material 22 appears near the surface 32.
The first base material 21 in such a state can be strongly bonded to the second base material 22 based on chemical bonding.

  Here, in the present specification, the state in which the surface 32 is “activated” means a part of molecular bonds on the surface 32 of the bonding film 3 as described above, specifically, for example, a silicone material. In addition to a state in which a bond that is not terminated in the bonding film 3 (hereinafter, also referred to as “unbonded bond” or “dangling bond”) is generated by cutting a part of the methyl group or the phenyl group. The bonding film 3 is referred to as an “activated” state including a state in which the dangling bonds are terminated by a hydroxyl group (OH group) and a state in which these states are mixed.

  The energy applied to the bonding film 3 may be applied using any method. For example, a method of bringing plasma into contact with the bonding film 3 (applying plasma energy), an energy beam to the bonding film 3 is used. Examples thereof include a method of irradiation, a method of heating the bonding film 3, a method of applying a compressive force (physical energy) to the bonding film 3, and a method of exposing the bonding film 3 to ozone gas (applying chemical energy). Thereby, the surface of the bonding film 3 can be activated efficiently.

Among these, as shown in FIG. 1 (e), it is particularly preferable to apply energy to the bonding film 3 by using a method in which plasma is brought into contact with the bonding film 3.
Here, prior to explaining why the method of bringing plasma into contact with the bonding film 3 is preferably used as a method for applying energy to the bonding film 3, ultraviolet light is selected as an energy ray, and ultraviolet light is applied to the bonding film 3. Problems in the case of irradiation will be described.

A: It takes a long time (for example, 1 minute to several tens of minutes) to activate the surface 32 of the bonding film 3. Moreover, when ultraviolet irradiation is made into a short time, in the process of joining the 1st base material 21 and the 2nd base material 22, long time (several tens of minutes or more) is required for the joining. That is, it takes a long time to obtain the joined body 1.
B: When ultraviolet rays are used, the ultraviolet rays are likely to pass through the bonding film 3 in the thickness direction. For this reason, depending on the constituent material (for example, resin material) of the base material (in this embodiment, the first base material 21), deterioration occurs at the interface (contact surface) with the bonding film 3 of the base material. The film 3 is easily peeled from the substrate.

  Further, when ultraviolet rays are transmitted in the thickness direction of the bonding film 3, they act on the entire bonding film 3, and, for example, methyl groups included in the polydimethylsiloxane skeleton are cut and removed in the entire film. That is, the amount of the organic component in the bonding film 3 is extremely reduced and the mineralization proceeds. For this reason, the flexibility of the bonding film 3 due to the presence of the organic component is lowered as a whole, and in the resulting bonded body 1, the in-layer peeling of the bonding film 3 easily occurs.

  C: Further, when the bonded body 1 is peeled off from the first base material 21 from the second base material 22 and the base materials 21 and 22 are separated and used for recycling or reuse, this operation is performed. Can exfoliate each base material 21 and 22 mutually by giving energy for exfoliation to joined object 1. At this time, for example, methyl groups (organic components) remaining in the bonding film 3 are cut and removed from the polydimethylsiloxane skeleton, and the cut organic components become gas. This gas (gaseous organic component) causes a gap in the bonding film 3 and the bonding film 3 is divided.

However, when the ultraviolet rays are irradiated, the entire bonding film 3 is mineralized as described above. Therefore, even when the peeling energy is applied, the organic component that becomes a gas is extremely small, and the bonding film 3 has a gap. There is a problem that it is difficult to occur.
On the other hand, in the case where the surface 32 of the bonding film 3 is exposed to plasma, a part of the molecular bond of the material constituting the bonding film 3 is selectively formed in the vicinity of the surface 32 of the bonding film 3, such as silicone. Part of the methyl and phenyl groups of the material is cleaved.

  Note that the breakage of the molecular bond by the plasma is caused not only by the chemical action based on the plasma charge but also by the physical action based on the plasma penning effect, and thus occurs in a very short time. Therefore, the bonding film 3 can be activated in a very short time (for example, about several seconds), and as a result, the bonded body 1 can be manufactured in a short time.

Further, the plasma selectively acts on the surface 32 of the bonding film 3 and hardly influences the inside thereof. For this reason, the molecular bond breakage occurs selectively in the vicinity of the surface 32 of the bonding film 3. That is, the bonding film 3 is selectively activated in the vicinity of the surface 32 thereof. Therefore, inconveniences (the inconveniences of B and C as described above) when the bonding film 3 is activated using ultraviolet rays are unlikely to occur.
As described above, when the plasma is used for the activation of the bonding film 3, the bonding film 3 hardly peels in the layer in the bonded body 1, and the first base material 21 is peeled from the second base material 22. Therefore, this peeling operation can be performed reliably.

  In addition, when the bonding film 3 is activated by ultraviolet irradiation, a change in the degree of activation of the bonding film 3 depending on the intensity of the irradiated ultraviolet ray is extremely large. For this reason, in order to activate the bonding film 3 to an extent suitable for bonding between the first base material 21 and the second base material 22, strict condition management of ultraviolet irradiation is necessary. Moreover, when not managing strictly, the joining strength of the 1st base material 21 and the 2nd base material 22 between the joined bodies 1 obtained arises.

On the other hand, when the bonding film 3 is activated by plasma, the change in the degree of activation of the bonding film 3 depending on the concentration (radical or active species) of the contacted plasma is gentle. Therefore, in order to activate the bonding film 3 to an extent suitable for bonding the first substrate 21 and the second substrate 22, it is not necessary to strictly manage the conditions for generating plasma. In other words, when plasma is used to activate the bonding film 3, the allowable range of manufacturing conditions for the bonded body 1 is wide. In addition, even if strict management is not performed, variations in the bonding strength between the first base material 21 and the second base material 22 hardly occur between the obtained bonded bodies 1.
Further, when the bonding film 3 is activated by ultraviolet irradiation, the bonding film 3 itself contracts (particularly, the film thickness decreases) with the activation of the bonding film 3, that is, the desorption of organic substances in the bonding film 3. There's a problem. When the bonding film 3 contracts, it becomes difficult to bond the first base material 21 and the second base material 22 with high bonding strength.

On the other hand, when the bonding film 3 is activated by plasma, the vicinity of the surface of the bonding film 3 is selectively activated as described above, so that the bonding film 3 is not contracted or very little. Therefore, even when the bonding film 3 is formed relatively thin, the first base material 21 and the second base material 22 can be bonded with high bonding strength. In this case, the bonded body 1 with high dimensional accuracy can be obtained, and the bonded body 1 can be thinned.
As described above, when the bonding film 3 is activated by plasma, there are many merits compared to the case where the bonding film 3 is activated by ultraviolet rays.

The plasma contact with the bonding film 3 may be performed under reduced pressure, but is preferably performed under atmospheric pressure. That is, it is preferable to treat the bonding film 3 with atmospheric pressure plasma. According to the atmospheric pressure plasma treatment, since the periphery of the bonding film 3 is not in a reduced pressure state, for example, when the methyl group included in the polydimethylsiloxane skeleton of the silicone material is cut and removed by the action of the plasma (the activity of the bonding film 3) This cutting can be prevented from proceeding unnecessarily during conversion.
Further, the plasma contact with the bonding film 3 is preferably performed by a remote plasma method in which remote processing is performed. As a result, it is possible to treat the bonding film 3 with only active species without directly exposing the bonding film 3 with ultraviolet rays in the plasma that are generated in minute amounts during plasma generation.

  [5] Next, the first base material 21 and the second base material 22 are overlapped so that the bonding film 3 and the second base material 22 are in close contact with each other (see FIG. 2F). Thereby, in the step [3], a hydroxyl group is introduced into the bonding surface 24 of the second base material 22 in an appropriate state. Further, in the step [4], the second group is added to the surface 32 of the bonding film 3. Since the adhesiveness to the material 22 is expressed, the bonding film 3 and the bonding surface 24 of the second base material 22 are chemically bonded. As a result, the first base material 21 and the second base material 22 are bonded via the bonding film 3, and the bonded body 1 as shown in FIG. 2G is obtained.

According to such a joining method, since the heat treatment at a high temperature (for example, 700 ° C. or higher) is not required, the first base material 21 and the second base material 22 made of a material having low heat resistance are used. Can also be used for bonding.
In addition, since the first base material 21 and the second base material 22 are bonded via the bonding film 3, there is an advantage that the constituent materials of the base materials 21 and 22 are not restricted.

From the above, according to the present invention, the range of selection of each constituent material of the first base material 21 and the second base material 22 can be expanded.
Here, in this step, a mechanism for bonding the first base material 21 and the second base material 22, that is, a mechanism for bonding the surface 32 of the bonding film 3 and the second base material 22 bonding surface 24. explain.

In the present invention, hydroxyl groups are exposed on the bonding surface 24 of the second substrate 22. Therefore, in this step [5], when the bonding film 3 formed on the first base material 21 and the bonding surface 24 of the second base material 22 are brought into contact with each other, the bonding film 3 and the hydroxyl group present on the bonding surface 24 of the second substrate 22 attract each other by hydrogen bonding, and an attractive force is generated between the hydroxyl groups. It is inferred that the first base material 21 and the second base material 22 are joined by this attractive force.
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 first base material 21 and the second base material 22, the bonds in which the hydroxyl groups are bonded are bonded to each other. Thereby, it is guessed that the 1st base material 21 and the 2nd base material 22 are joined more firmly.

Further, bonds that are not terminated on the surface and inside of the bonding film 3 of the first base member 21 and the bonding surface 24 and inside of the second base member 22, that is, unbonded hands (dangling bonds). When the first base material 21 and the second base material 22 are bonded together, these unbonded hands are recombined. Since this recombination occurs in a complicated manner so as to overlap (entangle) each other, a network-like bond is formed at the bonding interface. Thereby, the bonding film 3 and the second base material 22 are particularly strongly bonded.
As described above, the joined body (joined body of the present invention) 1 shown in FIG. 2G can be obtained.

The bonded body 1 obtained in this way exhibits bonding strength in both the thickness direction and the surface direction between the first base material 21 and the second base material 22.
In addition, it is preferable that the joining strength of the thickness direction between the 1st base material 21 and the 2nd base material 22 is 5 MPa (50 kgf / cm < ² >) or more, and is 10 MPa (100 kgf / cm < ² >) or more. More preferably. The bonded body 1 having such a bonding strength in the thickness direction can sufficiently prevent the bonding film 3 from peeling off due to the tensile force. 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.
In addition, when obtaining the joined body 1 or after obtaining the joined body 1, at least one of the following two steps ([6A] and [6B]) is performed on the joined body 1 as necessary. One step (step of increasing the bonding strength of the bonded body 1) may be performed. Thereby, the joint strength of the joined body 1 can be further improved easily.

[6A] As shown in FIG. 2 (h), the obtained bonded body 1 is pressurized in a direction in which the first base material 21 and the second base material 22 approach each other.
Thereby, the surface of the bonding film 3 is closer to the surface of the first substrate 21 and the surface of the second substrate 22, respectively, and the bonding strength in the bonded body 1 can be further increased.
Further, by pressurizing the bonded body 1, the gap remaining at the bonded interface in the bonded body 1 can be crushed and the bonded area can be further expanded. Thereby, the joint strength in the joined body 1 can be further increased.

In addition, what is necessary is just to adjust this pressure suitably according to conditions, such as each constituent material of each of the 1st base material 21 and the 2nd base material 22, each thickness, and a joining apparatus. Specifically, although it is slightly different depending on the constituent material of the first base material 21 and each thickness, it is preferably about 5 to 60 MPa, more preferably about 20 to 50 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 each constituent material of the 1st base material 21, there exists a possibility that damage etc. may arise in the 1st base material 21. FIG.
The time for pressurization is not particularly limited, but is preferably about 10 seconds to 30 minutes. In addition, what is necessary is just to change suitably the time to pressurize according to the pressure at the time of pressurizing. Specifically, the higher the pressure at which the bonded body 1 is pressed, the more the bonding strength can be improved even if the pressing time is shortened.

[6B] As shown in FIG. 2H, the obtained bonded body 1 is heated.
Thereby, the joint strength in the joined 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 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.
In the step [2], when the silicone material contained in the bonding film 3 is not completely cured (in the case of semi-curing), in this step, the bonded body 1 is cured when heated. It may be. By adopting such a configuration, the bonding film 3 has a lower hardness and higher followability with respect to the surface shape of the second base material 22 than in the case where the bonding film 3 is completely cured. Therefore, the bonding strength between the first base material 21 and the second base material 22 can be further improved.

Moreover, when performing both said process [6A] and [6B], it is preferable to perform these simultaneously. That is, as shown in FIG. 2 (h), it is preferable to heat the bonded body 1 while pressurizing it. 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.
By performing the steps as described above, it is possible to easily further improve the bonding strength in the bonded body 1.

<Droplet ejection head>
Next, an embodiment in which the joined body of the present invention is applied to an ink jet recording head will be described.
FIG. 3 is a longitudinal sectional view showing an ink jet recording head (droplet discharge head) obtained by applying the joined body of the present invention, and FIG. 4 shows an embodiment of an ink jet printer including the ink jet recording head shown in FIG. It is the schematic which shows a form. In the following description, the upper side in FIG. 3 is referred to as “upper” and the lower side is referred to as “lower”.

The ink jet recording head 100 shown in FIG. 3 (hereinafter sometimes simply referred to as “head 100”) is mounted on an ink jet printer 9 as shown in FIG.
The ink jet printer 9 shown in FIG. 4 includes an apparatus main body 92, a tray 921 in which the recording paper P is placed 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 is composed of, for example, a liquid crystal display, an organic EL display, an LED lamp, 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 a head 100 having a large number of nozzle holes 11, an ink cartridge 931 that supplies ink to the head 100, and a carriage 932 on which the head 100 and the ink cartridge 931 are 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 100 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 drive circuit that drives the printing device 94 (carriage motor 941), and a paper feeding device 95 (paper feeding motor 951). Drive circuit, a communication circuit for obtaining print data from a host computer, and a CPU that is electrically connected to these and performs various controls in each unit.

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

Hereinafter, the head 100 will be described in detail with reference to FIG.
As shown in FIG. 3, the head 100 includes a nozzle plate 10, a discharge liquid storage chamber forming substrate (substrate) 20 provided on the nozzle plate, and a vibration film 29 provided on the discharge liquid storage chamber forming substrate 20. A support plate 40 provided on the vibration film 29, and a piezoelectric element (vibration means) 50 and a case head 60 provided on the support plate 40. In this embodiment, the head 100 constitutes a piezo jet head.

A plurality of discharge liquid storage chambers (pressure chambers) 26 for storing ink are formed on the discharge liquid storage chamber forming substrate 20 (hereinafter referred to as “substrate 20” for short). 26, a discharge liquid supply chamber 27 for supplying ink to each discharge liquid storage chamber 26 is formed.
As shown in FIG. 3, each of the discharge liquid storage chambers 26 and the discharge liquid supply chambers 27 has a substantially rectangular shape in plan view, and the width (short side) of each of the discharge liquid storage chambers 26 is the discharge liquid supply. It is narrower than the width (short side) of the chamber 27.

Further, each discharge liquid storage chamber 26 is arranged so as to be substantially perpendicular to the discharge liquid supply chamber 27, and each discharge liquid storage chamber 26 and the discharge liquid supply chamber 27 are as a whole in plan view. It has a comb shape.
The material constituting the substrate 20 is not particularly limited. For example, silicon materials such as single crystal silicon, polycrystalline silicon, and amorphous silicon, metal materials such as stainless steel, glass materials such as quartz glass, alumina Ceramic materials such as graphite, carbon materials such as graphite, polyolefins, polyvinyl chloride, acrylonitrile-styrene copolymers (AS resins), resin materials such as silicone resins, etc., one or more of these Can be used in combination.

Moreover, the material which gave each process, such as an oxidation process (oxide film formation), a plating process, a passivation process, a nitriding process, to the above materials may be used.
Among these, the constituent material of the substrate 20 is preferably a silicon material or stainless steel. Since such a material is excellent in chemical resistance, even if it is exposed to ink for a long time, the substrate 20 can be reliably prevented from being deteriorated or deteriorated. Moreover, since these materials are excellent in workability, the substrate 20 with high dimensional accuracy can be obtained. For this reason, the accuracy of the volume of the discharge liquid storage chamber 26 and the discharge liquid supply chamber 27 is increased, and the head 100 capable of high-quality printing is obtained.

The discharge liquid supply chamber 27 communicates with a discharge liquid supply path 61 provided in a case head 60 described later, and is a part of a reservoir 70 that functions as a common ink chamber that supplies ink to the plurality of discharge liquid storage chambers 26. Parts.
The nozzle plate 10 is bonded to the lower surface of the substrate 20 (the surface opposite to the vibration film 29; one surface) through the adhesive layer 15 so as to cover the discharge liquid storage chamber 26 and the discharge liquid supply chamber 27. Yes.

Nozzle holes 11 are formed (perforated) in the nozzle plate 10 so as to correspond to the respective discharge liquid storage chambers 26. By extruding the ink (discharge liquid) stored in the discharge liquid storage chamber 26 from the nozzle hole 11, the ink is discharged as droplets.
The nozzle plate 10 constitutes the lower surface of the inner wall surface of each discharge liquid storage chamber 26 and the discharge liquid supply chamber 27. That is, the nozzle plate 10, the substrate 20, and the vibration film 29 define each discharge liquid storage chamber 26 and the discharge liquid supply chamber 27.

Examples of the material constituting the nozzle plate 10 include silicon materials, metal materials, glass materials, ceramic materials, carbon materials, resin materials, or one or more of these materials as described above. The composite material etc. which were combined are mentioned.
Among these, it is preferable that the constituent material of the nozzle plate 10 is a silicon material or stainless steel. Since such a material is excellent in chemical resistance, it is possible to reliably prevent the nozzle plate 10 from being altered or deteriorated even when exposed to ink for a long time. Moreover, since these materials are excellent in workability, the nozzle plate 10 with high dimensional accuracy can be obtained. For this reason, the head 100 with high reliability is obtained.

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

A vibration film 29 is bonded to the upper surface (the other surface) of the substrate 20 through the adhesive layer 25 so as to cover the discharge liquid storage chamber 26 and the discharge liquid supply chamber 27.
The vibration film 29 constitutes the upper surface of the inner wall surface of each discharge liquid storage chamber 26 and the discharge liquid supply chamber 27. That is, each of the discharge liquid storage chambers 26 and the discharge liquid supply chamber 27 is defined by the vibration film 29, the substrate 20, and the nozzle plate 10. In addition, since the vibration film 29 is securely bonded to the substrate 20, the liquid tightness of each discharge liquid storage chamber 26 and the discharge liquid supply chamber 27 is ensured.

Furthermore, the vibration film 29 has a function of elastic deformation. Therefore, the volume of the discharge liquid storage chamber 26 can be changed by displacing (vibrating) the vibration film 29 via the support plate 40 due to the distortion generated in the piezoelectric element 50. As a result, ink is discharged. The
In the present invention, the vibration film 29 is composed of an aramid resin as a main material, and the above-described second base material 22 is applied. Since the aramid resin is excellent in chemical resistance, it is possible to reliably prevent the vibration film 29 from being altered or deteriorated even when exposed to ink for a long time. For this reason, ink can be stored in the discharge liquid storage chamber 26 and the discharge liquid supply chamber 27 for a long period of time. Furthermore, since these are materials that can be elastically deformed at high speed, the volume of the discharge liquid storage chamber 26 can be changed at high speed, and as a result, ink can be discharged with high accuracy.

A support plate 40 is bonded to the upper surface of the vibration film 29 through an adhesive layer 45 so as to correspond to a part of the vibration film 29.
The bonding film 3 described above is applied to the adhesive layer 45. In other words, the bonding method of the present invention is applied to bonding of the support plate 40 (first base material 21) and the vibration film 29 (second base material 22) via the adhesive layer 45 (bonding film 3). The bonded body of the present invention is constituted by the support plate 40 (first base material 21), the vibration film 29 (second base material 22), and the adhesive layer 45 (bonding film 3).

The support plate 40 has a function of propagating the distortion generated in the piezoelectric element 50 to the vibration film 29 through this. Thereby, by generating distortion in the piezoelectric element 50, the vibration film 29 is displaced, and as a result, a volume change in each discharge liquid storage chamber 26 can be surely generated.
Examples of the material constituting the support plate 40 include a silicon material, a metal material, a glass material, a ceramic material, a carbon material, a resin material, or a combination of one or more of these materials as described above. Materials and the like.

Among these, it is preferable that the constituent material of the support plate 40 is a silicon material or stainless steel (SUS). Such a material has excellent strength. Therefore, the distortion generated in the piezoelectric element 50 is more reliably propagated to the vibration film 29, so that the ink is ejected with higher accuracy.
In the present embodiment, the vibration plate (sealing plate) that covers the discharge liquid storage chamber 26 and the discharge liquid supply chamber 27 by the laminate in which the above-described vibration film 29 and the support plate 40 are bonded via the adhesive layer 45. ) Is configured.

A piezoelectric element (vibrating means) 50 is joined to a part of the upper surface of the support plate 40 (in FIG. 3, an island-shaped portion formed in an island shape near the center of the upper surface of the support plate 40).
The piezoelectric element 50 is constituted by a laminate of a piezoelectric layer 51 made of a piezoelectric material and an electrode film 52 that applies a voltage to the piezoelectric layer 51. In such a piezoelectric element 50, when a voltage is applied to the piezoelectric layer 51 through the electrode film 52, a distortion corresponding to the voltage is generated in the piezoelectric layer 51 (reverse piezoelectric effect). This distortion causes the vibration film 29 to bend (vibrate) through the support plate 40 and change the volume of the discharge liquid storage chamber 26. Since the piezoelectric element 50 having such a configuration is reliably bonded to the support plate 40, the distortion generated in the piezoelectric element 50 can be reliably converted into the displacement of the vibration film 29 via the support plate 40. As a result, the volume of each discharge liquid storage chamber 26 is reliably changed.

  The lamination direction of the piezoelectric layer 51 and the electrode film 52 is not particularly limited, and may be a direction parallel to the support plate 40 or a direction orthogonal thereto. When the stacking direction of the piezoelectric layer 51 and the electrode film 52 is a direction orthogonal to the support plate 40 as shown in FIG. Say Layer Piezo). If the piezoelectric element 50 is MLP, the displacement amount of the support plate 40 can be increased, which has the advantage that the adjustment range of the ink ejection amount is large.

The surface of the piezoelectric element 50 adjacent to (in contact with) the support plate 40 differs depending on the arrangement method of the piezoelectric element 50, but the surface on which the piezoelectric layer is exposed, the surface on which the electrode film is exposed, or the piezoelectric layer and the electrode Either side of the membrane is exposed.
As a material constituting the piezoelectric layer 51 in the piezoelectric element 50, for example, barium titanate, lead zirconate, lead zirconate titanate, zinc oxide, aluminum nitride, lithium tantalate, lithium niobate, crystal, and the like are available. Can be mentioned.

On the other hand, as a material constituting the electrode film 52, for example, various metal materials such as Fe, Ni, Co, Zn, Pt, Au, Ag, Cu, Pd, Al, W, Ti, Mo, or an alloy containing them. Is mentioned.
Here, the support plate 40 described above has a recess 53 formed in an annular shape so as to surround a position corresponding to the piezoelectric element 50. That is, the support plate 40 is provided on the vibration film 29 so as to correspond to a part (island portion), and at a position corresponding to the piezoelectric element 50, a part of the support plate 40 is annular. Are isolated in an island shape with a recess 53 therebetween. By adopting a configuration in which the piezoelectric element 50 is bonded to such an island-shaped portion, distortion generated in the piezoelectric element 50 can be more reliably propagated to the vibration film 29, so that the bending in the vibration film 29 can be prevented. It will occur more reliably.

The electrode film 52 of the piezoelectric element 50 is electrically connected to a drive IC (not shown). Thereby, the operation of the piezoelectric element 50 can be controlled by the driving IC.
Further, the case head 60 is joined to a part of the upper surface of the support plate 40 (in FIG. 3, a portion surrounding the island-shaped portion with the recess 53 therebetween). In this way, the case head 60 and the support plate 40 are joined to reinforce a so-called cavity portion composed of a laminated body of the nozzle plate 10, the substrate 20, the vibration film 29 and the support plate 40. The tee portion can be reliably prevented from being twisted or warped.

Examples of the material constituting the case head 60 include a silicon material, a metal material, a glass material, a ceramic material, a carbon material, a resin material, or a combination of one or more of these materials as described above. Materials and the like.
Among these, the constituent material of the case head 60 is preferably polyphenylene sulfide (PPS), a modified polyphenylene ether resin such as Zylon (“Zylon” is a registered trademark), or stainless steel. Since these materials have sufficient rigidity, they are suitable as constituent materials of the case head 60 that supports the head 100.

  Further, the vibration film 29, the adhesive layer 45, and the support plate 40 have a through hole 28 at a position corresponding to the discharge liquid supply chamber 27. Through the through hole 28, the discharge liquid supply path 61 provided in the case head 60 and the discharge liquid supply chamber 27 communicate with each other. The discharge liquid supply path 61 and the discharge liquid supply chamber 27 constitute part of a reservoir 70 that functions as a common ink chamber that supplies ink to the plurality of discharge liquid storage chambers 26.

  In such a head 100, after taking ink from an external discharge liquid supply means (not shown) and filling the interior from the reservoir 70 to the nozzle hole 11 with ink, each discharge liquid storage chamber 26 is detected by a recording signal from the drive IC. Each piezoelectric element 50 corresponding to is operated. Accordingly, the vibration film 29 is bent (vibrated) via the support plate 40 due to the reverse piezoelectric effect of the piezoelectric element 50. As a result, for example, when the volume in each discharge liquid storage chamber 26 contracts, the pressure in each discharge liquid storage chamber 26 increases instantaneously, and ink is pushed out (discharged) from the nozzle hole 11 as a droplet.

In this way, in the head 100, an arbitrary character prints a figure or the like by applying a voltage to the piezoelectric element 50 at a position to be printed via the driving IC, that is, sequentially inputting the ejection signal. Can do.
The head 100 is not limited to the configuration described above, and may include, for example, an electrostatic actuator instead of the piezoelectric element 50 as a vibration unit.

However, as in the present embodiment, since the vibration means is composed of a piezoelectric element, the degree of bending that occurs in the vibration film 29 can be easily controlled. As a result, the size of the ink droplet can be easily controlled.
As mentioned above, although the joining method and joined body of this invention were demonstrated based on embodiment of illustration, this invention is not limited to these.

For example, in the bonding method of the present invention, one or more optional steps may be added as necessary.
Needless to say, the joined body of the present invention is applicable to other than the droplet discharge head. Specifically, the joined body of the present invention can be applied to, for example, a mounting substrate such as a flexible substrate.

Next, specific examples of the present invention will be described.
1. Formation of bonded body (Example 1)
First, a stainless steel (SUS) substrate having a length of 1 cm × width 3 cm × thickness of 80 μm is prepared as a first base material (substrate), and a length of 1 cm × width 3 cm × thickness as a second base material (counter substrate). A 4 μm aramid film was prepared.

Next, a polyester-modified silicone material ("XR32-A1612" manufactured by Momentive Performance Material Japan G.K.) obtained by a dehydration condensation reaction between the silicone material and the polyester resin is prepared, and spin coating is performed. The liquid material was supplied onto the SUS substrate to form a liquid film.
Next, this liquid film was heated at 100 ° C. for 1 hour, dried and cured to form a bonding film (average thickness: about 1 μm) on the SUS substrate.

Next, plasma was brought into contact with the bonding film formed on the SUS substrate under the following conditions using an atmospheric pressure plasma apparatus. As a result, the bonding film was activated to develop adhesiveness on the surface.
<Plasma treatment conditions>
・ Processing gas: Mixed gas of helium gas and oxygen gas ・ Gas supply speed: 10 SLM
・ Distance between electrodes: 1mm
・ Applied voltage: 1 kVp-p
-Voltage frequency: 40 MHz
・ Movement speed: 1mm / sec

Next, the aramid film was subjected to corona discharge treatment under the following conditions using a corona discharge treatment apparatus. Thereafter, the aramid film was washed with pure water at 60 ° C.
<Corona discharge treatment conditions>
・ Processing gas: Air ・ Distance between electrodes: 1 mm
・ Applied voltage: 1 kVp-p
・ Frequency: 100 kHz
・ Movement speed: 1mm / sec

The surface free energy of the aramid film after the treatment was analyzed based on the contact angle measured using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., “DM-501”). The p component and h component were 27.5 mJ / m ² , 45.1 mJ / m ² and 19.5 mJ / m ² , respectively.
Next, the surface of the bonding film in contact with the plasma and the surface of the aramid film subjected to the surface treatment are in contact with each other, and further, the SUS substrate and the aramid film are formed in a cross shape. Are superimposed. That is, the superposition was performed so that the joint where the base materials were joined to each other via the joining film formed a square shape (vertical 1 cm × horizontal 1 cm).

Then, the SUS substrate and the aramid film were maintained at room temperature (around 25 degrees) for 1 minute while being pressurized at 50 MPa. Thereafter, this was heated at 200 ° C. for 1 hour to improve the bonding strength of the bonding film.
By passing through the above process, the joined body of Example 1 with which the SUS board | substrate and the aramid film were joined via the joining film | membrane was obtained.

(Example 2)
Instead of corona discharge treatment for the aramid film, plasma treatment was performed, and furthermore, the surface of the aramid film was washed with ethanol instead of water to obtain a joined body in the same manner as in Example 1. It was.
The plasma processing conditions using the plasma processing apparatus were as shown below.
<Plasma treatment conditions>
・ Processing gas: Mixed gas of helium gas and oxygen gas ・ Gas supply speed: 10 SLM
・ Distance between electrodes: 1mm
・ Applied voltage: 1 kVp-p
-Voltage frequency: 40 MHz
・ Movement speed: 1mm / sec

(Comparative Example 1)
A joined body was obtained in the same manner as in Example 1 except that the corona discharge treatment and washing with water on the surface of the aramid film were omitted.
(Comparative Example 2)
A joined body was obtained in the same manner as in Example 1 except that the corona discharge treatment on the surface of the aramid film was omitted.

(Comparative Example 3)
A joined body was obtained in the same manner as in Example 1 except that washing with water on the surface of the aramid film was omitted.
(Comparative Example 4)
A joined body was obtained in the same manner as in Example 2 except that washing with water on the surface of the aramid film was omitted.
(Comparative Example 5)
A bonded body was obtained in the same manner as in Example 1 except that the plasma treatment for the bonding film formed on the SUS substrate was omitted.

2. Evaluation of Bonded Body For the bonded bodies of each Example and each Comparative Example, the peel strength with respect to the surface direction was measured as follows based on the peel strength test (specified in JIS-G3469).
That is, for each joined body of each example and each comparative example, the load (joint strength) when holding one end of the aramid film and peeling off at a rate of 10 mm / min in the direction of 90 ° at room temperature is 90 °. It measured using the peel peeling test apparatus (the product made by Imada, "NX-500NE"). Then, the bonding strength was evaluated according to the following criteria.
<Evaluation criteria for peel strength test>
○: 0.2 N / mm or more ×: less than 0.2 N / mm These results are shown in Table 1.

As is apparent from Table 1, the joined bodies obtained in each Example were able to join the SUS substrate and the aramid film with excellent joining strength via the joining film.
On the other hand, the joined body obtained in each comparative example is obtained by omitting any one of energy application to the joining film, hydroxyl group introduction treatment to the aramid film, and contact of the polar solvent to the aramid film. The substrate and the aramid film could not be bonded with excellent bonding strength via the bonding film.

  DESCRIPTION OF SYMBOLS 1 ... Bonded body 10 ... Nozzle plate 100 ... Inkjet recording head 11 ... Nozzle plate 15 ... Adhesive layer 20 ... Discharge liquid storage chamber forming substrate 21 ... First base material 22 ... Second Substrate 23, 24 …… Joint surface 25 …… Adhesive layer 26 …… Discharge liquid storage chamber 27 …… Discharge liquid supply chamber 28 …… Through hole 29 …… Vibration film 3 …… Joint film 30 …… Liquid film 32 ... ... Surface 35 ... Liquid material 40 ... Support plate 45 ... Adhesive layer 50 ... Piezoelectric element 51 ... Piezoelectric layer 52 ... Electrode film 53 ... Recessed part 60 ... Case head 61 ... Discharge liquid supply path 70 …… Reservoir 9 …… Inkjet printer 92 …… Device main body 921 …… Tray 922 …… Discharge port 93 …… Head unit 931 …… Ink cartridge 932 …… Carriage 94 ... Printer 941 ... Carrying motor 942 ... Reciprocating mechanism 943 ... Carriage guide shaft 944 ... Timing belt 95 ... Feeding device 951 ... Feeding motor 952 ... Feeding roller 952a ... Following roller 952b ... … Drive roller 96 …… Control unit 97 …… Operation panel P …… Recording paper

Claims (8)

Forming a liquid film by supplying a liquid material containing a silicone material to the first substrate;
Drying and / or curing the liquid film to form a bonding film on the first substrate;
After the surface of the second substrate composed mainly of an aramid resin is subjected to a hydroxyl group introduction treatment for introducing a hydroxyl group, a polar solvent is brought into contact with the surface of the second substrate subjected to the hydroxyl group introduction treatment A process of
A step of expressing adhesiveness on the surface of the bonding film and in the vicinity of the surface by applying energy to the bonding film formed on the first substrate;
The first base material and the second base material are brought into contact with each other through the bonding film expressing the adhesiveness, and the first base material and the second base material are interposed through the bonding film. And a step of obtaining a joined joined body. The silicone material has a unit structure represented by the following chemical formula (1) in the branch part and a unit structure represented by at least one of the following chemical formula (2) and the following chemical formula (3) in the connecting part. 2. The bonding method according to claim 1, wherein the terminal portion has a branched polyorganosiloxane skeleton having a unit structure represented by at least one of the following chemical formula (4) and the following chemical formula (5).

[Wherein, each R ¹ independently represents a methyl group or a phenyl group, and X represents a siloxane residue. ]   The silicone material is a polyester-modified silicone material obtained by a dehydration condensation reaction of a polyester resin obtained by esterification of trimethylolpropane and terephthalic acid to the branched polyorganosiloxane skeleton. The joining method according to claim 2.   The bonding method according to claim 2, wherein the silicone material is an epoxy-modified silicone material obtained by an addition reaction of an epoxy resin with the branched polyorganosiloxane skeleton.   The bonding method according to claim 1, wherein the hydroxyl group introduction treatment for the second base material is at least one of plasma treatment and corona discharge treatment.   The joining method according to claim 1, wherein the polar solvent is water or alcohols.   The joining method according to any one of claims 1 to 6, wherein the first base material includes a metal-based material as a main material.   A joined body obtained by joining the first base material and the second base material through the joining film by the joining method according to claim 1.

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