DESCRIPTION

Title of Invention

MATERIAL WITH PRIMER AND BONDED ARTICLE

Technical Field

[0001]

The present invention relates to a material with a primer that is favorable for a purpose of firmly welding materials, such as a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber, a method for producing the same, a joined article using the material with a primer, and a method for producing the same.

Background Art

[0002]

Mechanical bonding, adhesive bonding, and welding have been used in the fabrication process of plastic products, such as automobile components, medical equipments, and home electric appliances, and welding is a bonding method that is highly reliable and productively useful. Specifically, ultrasonic welding, vibration welding, thermal welding, hot air welding, induction welding, and the like have been used. Welding is generally used for bonding thermoplastic resin materials of the same kind, and can also be used for bonding thermoplastic resin materials of different kinds having solubility parameters (SP values) that are close to each other. For example, PTLs 1 and 2 describe a technique of ultrasonic welding of a molded article obtained by molding a thermoplastic resin composition and a thermoplastic resin of a different kind from the thermoplastic resin of the molded article, with a thermoplastic sheet material having a functional group and a reinforcing fiber bundle intervening therebetween. PTL 3 describes a technique of ultrasonic welding of materials to be welded, with an intermediate layer intervening therebetween, in which the intermediate layer is vibrated by fixing to an ultrasonic resonator horn.

Citation List Patent Literatures

[0003] PTL 1: JP 2017-202667 A PTL 2: JP 2017-206014 A PTL 3: JP 2008-284862 A

Summary of Invention Technical Problem [0004]

The strength of the welded part is exerted through entanglement and crystallization of the molecules caused by molecular diffusion at the bonding interface. However, the ultrasonic welding or the like described in PTLs 1 to 3 have an issue that the entanglement and crystallization caused by molecular diffusion are insufficient, and a sufficient bonding strength cannot be obtained. [0005]

The present invention has been made in view of the technical background, and a problem to be solved thereby is to provide a material with a primer that is capable of firmly bonding materials, such as a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber, and of enhancing the durability thereof for a long period of time, and relating techniques thereof. The relating techniques include a method for producing the material with a primer, a bonded article using the material with a primer, and a method for producing the same.

Solution to Problem [0006]

Methods capable of solving the problem include high frequency dielectric heating, in which a strong high frequency electric field is applied to generate molecular level collision, vibration, and friction inside the substance. However, the effect thereof cannot be exerted if the loss coefficient of the material is low.

Compounds having a relatively high loss coefficient include a vinyl chloride resin, polyamide, a phenol resin, polyurea, an epoxy resin, and the like, but an organic layer for welding containing these compounds has not yet been developed.

[0007]

As a result of the earnest investigations by the present inventors for solving the problem, it has been found that the problem can be solved by using a polymer of an in situ polymerization composition containing a resin having a particular loss coefficient, as a primer layer laminated on an adherend material layer, and thus the present invention has been completed. The following means are provided.

[0008]

In the description herein, bonding means that articles are connected to each other, and adhesion and welding are subordinate concepts thereof. Adhesion means that two adherends (i.e., articles to be adhered) are made into a bonded state through an organic material (such as a thermosetting resin and a thermoplastic resin) in the form of a tape, an adhesive, or the like, and welding means that a thermoplastic resin or the like is melted with heat, and a bonded state is created through entanglement and crystallization by molecular diffusion caused by contact pressing and cooling.

[0009]

[1] A material with a primer, comprising a material layer and one layer or plural layers of a primer layer laminated on the material layer, at least one layer of the primer layer being an in situ polymerization composition layer comprising a polymer of an in situ polymerization composition comprising a resin having a loss coefficient of 0.30 ε·tanδ or more.

[2] The material with a primer according to the item [1], wherein the resin having a loss coefficient of 0.30 ε·tanδ or more is at least one kind selected from the group consisting of a vinyl chloride resin, a phenol resin, and a polyamide.

[3] The material with a primer according to the item [1] or [2], wherein the in situ polymerization composition contains at least one kind of the following items (1) to (6):

(1) a combination of a bifunctional isocyanate compound and a bifunctional compound having hydroxy groups,

(2) a combination of a bifunctional isocyanate compound and a bifunctional compound having amino groups,

(3) a combination of a bifunctional epoxy compound and a bifunctional compound having hydroxy groups,

(4) a combination of a bifunctional epoxy compound and a bifunctional carboxy compound,

(5) a combination of two kinds of compounds selected from the group consisting of a bifunctional epoxy compound and a bifunctional thiol compound, and

(6) a monofunctional radically polymerizable monomer.

[4] The material with a primer according to any one of the items [1] to [3], wherein the material layer contains at least one kind selected from the group consisting of a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber.

[5] The material with a primer according to any one of the items [1] to [4], wherein the in situ polymerization composition has a content of the resin having a loss coefficient of 0.30 ε·tanδ or more of 0.5 to 50% by mass based on the total amount of the in situ polymerization composition.

[0010]

[6] A bonded article including a material, which is at least one kind selected from the group consisting of a metal, glass, ceramics, fiber _: reinforced plastics, a resin, and rubber, welded to the primer layer of the material with a primer according to any one of the items [1] to [5].

[0011]

[7] A method for producing the material with a primer according to any one of the items [1] to [5], comprising polymerizing an in situ polymerization composition containing a resin having a loss coefficient of 0.30 ε·tanδ or more, on a material layer.

[8] The method for producing the material with a primer according to the item [7], wherein the resin having a loss coefficient of 0.30 ε·tanδ or more is at least one kind selected from the group consisting of a vinyl chloride resin, a phenol resin, and a polyamide.

[9] The method for producing the material with a primer according to the item [7] or [8], wherein the in situ polymerization composition contains at least one kind of the following items (1) to (6):

(1) a combination of a bifunctional isocyanate compound and a bifunctional compound having hydroxy groups,

(2) a combination of a bifunctional isocyanate compound and a bifunctional compound having amino groups,

(3) a combination of a bifunctional epoxy compound and a bifunctional compound having hydroxy groups,

(4) a combination of a bifunctional epoxy compound and a bifunctional carboxy compound, (5) a combination of two kinds of compounds selected from the group consisting of a bifunctional epoxy compound and a bifunctional thiol compound, and

(6) a monofunctional radically polymerizable monomer.

[10] The method for producing the material with a primer according to any one of the items [7] to [9], wherein the material layer contains at least one kind selected from the group consisting of a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber.

[0012]

[11] A method for producing a bonded article, comprising welding a material, which is at least one kind selected from the group consisting of a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber, to the primer layer of the material with a primer according to any one of the items [1] to [5].

[12] The method for producing a bonded article according to the item [11], wherein the welding is high frequency welding.

[0013]

[13] An in situ polymerization composition for a primer layer, comprising a resin having a loss coefficient of 0.30 ε·tanδ or more and at least one kind of the following items (1) to (6):

(1) a combination of a bifunctional isocyanate compound and a bifunctional compound having hydroxy groups,

(2) a combination of a bifunctional isocyanate compound and a bifunctional compound having amino groups,

(3) a combination of a bifunctional epoxy compound and a bifunctional compound having hydroxy groups,

(4) a combination of a bifunctional epoxy compound and a bifunctional carboxy compound,

(5) a combination of two kinds of compounds selected from the group consisting of a bifunctional epoxy compound and a bifunctional thiol compound, and

(6) a monofunctional radically polymerizable monomer.

[14] The in situ polymerization composition for a primer layer according to the item [13], wherein the resin having a loss coefficient of 0.30 ε·tanδ or more is at least one kind selected from the group consisting of a vinyl chloride resin, a phenol resin, and a polyamide. [15] The in situ polymerization composition for a primer layer according to the item [13] or [14], wherein the in situ polymerization composition has a content of the resin having a loss coefficient of 0.30 ε·tanδ or more of 0.5 to 50% by mass based on the total amount of the in situ polymerization composition.

Advantageous Effects of Invention [0014]

According to the present invention, a material with a primer that is capable of firmly bonding materials, such as a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber, and of enhancing the durability thereof for a long period of time, and relating techniques thereof can be provided.

Brief Description of Drawings [0015]

Fig. 1 is an explanatory view showing a structure of a material with a primer according to one embodiment of the present invention.

Fig. 2 is an explanatory view showing a structure of a material with a primer according to another embodiment of the present invention.

Fig. 3 is an explanatory view showing a structure of a material with a primer according to still another embodiment of the present invention.

Fig. 4 is an explanatory view showing a structure of a bonded article according to one embodiment of the present invention.

Fig. 5 is an explanatory view showing a structure of a bonded article according to another embodiment of the present invention.

Description of Embodiments [0016]

The material with a primer and related techniques thereof according to an embodiment of the present invention (which may be hereinafter referred to as a

"present embodiment") will be described in detail below.

In the description herein, the term "(meth)acryl" means acryl and/or methacryl, and the term "(meth)acrylate" means acrylate and/or methacrylate. [0017]

[Material with Primer]

The material with a primer of the present embodiment includes a material layer and one layer or plural layers of a primer layer laminated on the material layer, and at least one layer of the primer layer is an in situ polymerization composition layer containing a polymer of an in situ polymerization composition containing a resin having a loss coefficient of 0.30 ε·tanδ or more.

[0018]

As shown in Fig. 1, a material with a primer 1 according to one embodiment is a laminated article including a material layer 2 and one layer or plural layers of a primer layer 3 laminated on the material layer 2. In the present embodiment, at least one layer of the primer layer 3 is an in situ polymerization composition layer 31 containing a polymer of an in situ polymerization composition containing a resin having a loss coefficient of 0.30 ε·tanδ or more.

[0019]

In the present embodiment, the in situ polymerization composition means a composition that forms a thermoplastic structure, i.e., a linear polymer structure, through polyaddition reaction of a combination of reactive bifunctional compounds or through radical polymerization reaction of a particular monofunctional monomer, in the in situ state, i.e., on various materials. The in situ polymerization composition does not constitute a three-dimensional network with a crosslinked structure, but has thermoplasticity, as being different from a thermosetting resin constituting a three-dimensional network with a crosslinked structure.

[0020]

In the present embodiment, the primer layer means, for example, in the case where the material layer is bonded and integrated to a material (i.e., an bonding target), such as a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber, as in the bonded article described later, a layer that intervenes between the material layer and the bonding target and enhances the bonding strength of the material layer to the bonding target.

The in situ polymerization composition layer 31 is preferably a layer formed with a composition containing an in situ polymerization phenoxy resin. The in situ polymerization phenoxy resin is a resin that is also referred to as a thermoplastic epoxy resin, an in situ curing phenoxy resin, an in situ curing epoxy resin, or the like, and forms a thermoplastic structure, i.e., a linear polymer structure, through polyaddition reaction of a bifunctional epoxy resin and a bifunctional phenolcompound in the presence of a catalyst.

[0021]

<Material Layer 2>

The form of the material layer 2 is not particularly limited, and may be a bulk form or a film form.

The material constituting the material layer 2 is not particularly limited, and is preferably at least one kind selected from the group consisting of a metal, glass, ceramics, fiber-reinforced plastics (FRP), a resin, and rubber.

[0022]

Examples of the metal include aluminum, iron, copper, magnesium, and a steel. Among these, aluminum is preferred from the standpoint of weight reduction.

Examples of the glass include soda lime glass, lead glass, borosilicate glass, and quartz glass.

Examples of the ceramics include oxide ceramics, such as alumina, zirconia, and barium titanate, hydroxide ceramics, such as hydroxyapatite, carbide ceramics, such as silicon carbide, and nitride ceramics, such as silicon nitride.

[0023]

Examples of the fiber-reinforced plastics (FRP) include glass fiber-reinforced plastics (GFRP), carbon fiber-reinforced plastics (CFRP), boron fiber-reinforced plastics (BFRP), and aramid fiber-reinforced plastics (AFRP). Examples thereof also include a molded article formed from a glass fiber SMC (sheet molding compound) or a carbon fiber SMC.

[0024]

Examples of the resin include a thermoplastic resin, such as polypropylene (PP), polyamide 6 (PA6), polyamide 66 (PA66), modified polyphenylene ether (m-PPE), polyphenylene sulfide (PPS), polyetherimide (PEI), polycarbonate (PC), polybutylene terephthalate (PBT), and a (meth)acrylic resin. [0025]

Examples of the rubber include natural rubber, styrene-butadiene rubber, butadiene rubber, isoprene rubber, butyl rubber, halogenated butyl rubber, ethylene-propylene-diene rubber, butadiene-acrylonitrile copolymer rubber, chloroprene rubber, silicone rubber, and fluorine rubber.

[0026] In the case where the material layer 2 is a metal, the thickness thereof is preferably 1.5 μm or more, and more preferably 1.6 μm or more, from the standpoint of the strength. The upper limit of the thickness of the metal is not particularly limited, and is preferably 5 mm or less, and more preferably 3 mm or less.

In the case where the material layer 2 is glass, the thickness thereof is preferably 0.3 mm or more, and more preferably 0.5 mm or more, from the standpoint of the strength. The upper limit of the thickness of the glass is not particularly limited, and is preferably 30 mm or less, more preferably 10 mm or less, and further preferably 2 mm or less.

In the case where the material layer 2 is FRP or ceramics, the thickness thereof is preferably 0.3 mm or more, and more preferably 0.5 mm or more, from the standpoint of the strength. The upper limit of the thickness of the FRP and ceramics is not particularly limited, and is preferably 20 mm or less, more preferably 10 mm or less, and further preferably 2 mm or less.

In the case where the material layer 2 is a resin or rubber, the thickness thereof is preferably 10 μm or more, and more preferably 30 μm or more, from the standpoint of the strength. The upper limit of the thickness of the resin or rubber is not particularly limited, and is preferably 30 mm or less, and more preferably 10 mm or less.

[0027]

[Surface Treatment]

The material layer 2 may be subjected to a surface treatment for the purpose of removal of contamination on the surface thereof and/or an anchoring effect thereon.

In the case where the material layer 2 is a metal, glass, ceramics, or fiber-reinforced plastics (FRP), the surface treatment is preferably performed before laminating the primer layer 3.

[0028]

The surface treatment performed can form a roughened surface through formation of fine unevenness 21 on the surface of the material layer 2, as shown in Fig. 1. According to the procedure, the adhesiveness between the surface of the material layer 2 and the primer layer 3 can be improved. The surface treatment also can contribute to the enhancement of the bondability to the bonding target. [0029] The property of the surface of the material layer 2 having been subjected to the surface treatment in the aforementioned method may be altered in some cases from immediately after the surface treatment, due to the formation of the primer layer 3 and the like on the surface-treated surface. Accordingly, it is considered that the expression that identifies the property of the surface-treated surface of the material layer is impossible or impractical. Therefore, in the present embodiment, the surface-treated surface of the material layer is identified by the method of the surface treatment.

[0030]

Examples of the surface treatment include a degreasing treatment, an UV ozone treatment, a blasting treatment, a grinding treatment, a plasma treatment, a corona discharge treatment, a laser treatment, an etching treatment, a flame treatment, and a chemical conversion treatment.

The surface treatment is preferably a surface treatment that cleans the surface of the material layer 2 or a surface treatment that forms unevenness on the surface thereof, and specifically is preferably at least one kind selected from the group consisting of a degreasing treatment, an UV ozone treatment, a blasting treatment, a grinding treatment, a plasma treatment a corona discharge treatment, and a chemical conversion treatment.

Only one kind among the surface treatments may be performed, and two or more kinds thereof may be performed. The specific methods used for the surface treatments may be the known methods.

[0031]

The degreasing treatment is a method of removing contamination, such as fats and oils, on the surface of the material layer by dissolving with an organic solvent or the like, such as acetone and toluene.

[0032]

The UV ozone treatment is a method of cleaning or modifying the surface by the energy of an ultraviolet ray having a short wavelength emitted from a low pressure mercury lamp and the power of ozone (O3) generated thereby. For glass materials, the treatment may be one of surface cleaning methods for removing the organic impurities on the surface. In general, a surface cleaning and modifying equipment using a low pressure mercury lamp is referred to as an "UV ozone cleaner", an "UV cleaning device", an "ultraviolet ray surface modifier", or the like. [0033]

Examples of the blasting treatment include a wet blasting treatment, a shot blasting treatment, and a sand blasting treatment. Among these, a wet blasting treatment is preferred since a fine surface can be obtained, as compared to a dry blasting treatment.

[0034]

Examples of the grinding treatment include buff grinding using an abrasive cloth, roll grinding using abrasive paper (sandpaper), and electrolytic grinding.

[0035]

The plasma treatment is to render the material surface in a sensitive state through excitation of the molecules thereof by hitting the surface with a plasma beam created with a high voltage power supply and a rod, and examples thereof include an atmospheric plasma treatment method capable of applying hydroxy groups and polar groups on the material surface.

[0036]

Examples of the corona discharge treatment include a method applied to surface modification of a polymer film, which may be a method of generating hydroxy groups or polar groups on the surface from starting points, which are radicals generated through scission of the polymer main chain or side chain of the polymer surface layer with electrons emitted from an electrode.

[0037]

The laser treatment is a technique of improving the characteristics of the surface by quickly heating and cooling only the surface layer through laser irradiation, and is a method that is effective for roughening the surface. A known laser treatment technique may be used.

[0038]

Examples of the etching treatment include a chemical etching method, such as an alkali method, a phosphoric acid-sulfuric acid method, a fluoride method, a chromic acid-sulfuric acid method, and a salt iron method, and an electrochemical etching treatment, such as an electrolytic etching method.

[0039]

The flame treatment is a method of converting oxygen in the air into plasma by burning a mixed gas of a fuel gas and the air, and applying the oxygen plasma to the treatment target, so as to make the surface thereof hydrophilic. A known flame treatment technique may be used. [0040]

The chemical conversion treatment forms a chemical conversion film mainly on the surface of the material layer 2.

Examples of the chemical conversion treatment in the case where the material layer is a metal include a boehmite treatment and a zirconium treatment.

In the boehmite treatment, the material layer 2 is subjected to a hydrothermal treatment to form a boehmite film on the surface of the material layer 2. A reaction accelerator, such as ammonia and triethanolamine, may be added to water. For example, it is preferred that the material layer 2 is dipped in hot water at 90 to 100°C containing triethanolamine in a concentration of 0.1 to 5.0% by mass for 3 seconds to 5 minutes.

In the zirconium treatment, the material layer 2 is dipped, for example, in a liquid containing a zirconium salt, such as zirconium phosphate, to form a film of a zirconium compound on the surface of the material layer 2. For example, it is preferred that the material layer 2 is dipped in a liquid of a chemical agent for a zirconium treatment (for example, "Palcoat 3762" and "Palcoat 3796", produced by Nihon Parkerizing Co., Ltd.) at 45 to 70°C for 0.5 to 3 minutes. The zirconium treatment is preferably performed after the etching treatment by a caustic soda method.

[0041]

[Functional Group Applying Treatment]

A functional group applying treatment for applying a functional group to the surface of the material layer 2 may be performed.

[0042]

It is preferred that the material layer 2 is subjected to a functional group applying treatment subsequent to the aforementioned surface treatment before laminating the primer layer 3.

[0043]

The functional group applying treatment can form one layer or plural layers of a functional group-containing layer 4 between the material layer 2 and the primer layer 3, laminated in contact with the material layer 2 and the primer layer 3, as shown in Fig 2.

[0044] In the case where the functional group-containing layer 4 is formed by the functional group applying treatment, such an effect is obtained that the functional group of the functional group-containing layer 4 is reacted with the hydroxy group on the surface of the material layer 2 and the functional group of the resin constituting the primer layer, so as to form a chemical bond, with which the adhesiveness between the material layer 2 and the primer layer 3 is enhanced. An effect of enhancing the bondability to the bonding target can also be obtained. Accordingly, the functional group in the functional group-containing layer 4 is preferably a functional group that has reactivity with the hydroxy group and the functional group of the resin constituting the primer layer. Examples of the functional group include an epoxy group, an amino group, a mercapto group, an isocyanate group, a carboxy group, a hydroxy group, a vinyl group, and a (meth)acryloyloxy group.

[0045]

The functional group-containing layer 4 is preferably a layer that has a functional group introduced from at least one kind selected from the group consisting of a silane coupling agent, an isocyanate compound, and a thiol compound. [0046]

The functional group-containing layer 4 may be formed by treating the surface or the surface-treated surface of the material layer 2 with at least one kind selected from the group consisting of a silane coupling agent, an isocyanate compound, and a thiol compound before forming the primer layer 3.

[0047]

The method of forming the functional group-containing layer 4 with the silane coupling agent, the isocyanate compound, or the thiol compound is not particularly limited, and examples thereof include a spray coating method and a dipping method. Specifically, for example, such a method may be employed that the material layer is dipped in a solution of the silane coupling agent or the like having a concentration of 5 to 50% by mass at ordinary temperature to 100°C for 1 minute to 5 days, and then dried at ordinary temperature to 100°C for 1 minutes to 5 hours. In the description herein, the ordinary temperature means 5 to 35°C, and preferably 15 to 25°C.

[0048]

[Silane Coupling Agent] The silane coupling agent used may be, for example, a known one that is used for a surface treatment of glass fibers or the like. A silanol group formed through hydrolysis of the silane coupling agent or a silanol group obtained through oligomerization thereof is reacted with and bonded to the hydroxy group existing on the surface of the material layer 2, and thereby the functional group based on the structure of the silane coupling agent capable of chemically bonding to the primer layer 3 can be imparted to (introduced to) the material layer.

[0049]

The silane coupling agent is not particularly limited, and examples thereof that can be used include a silane coupling agent having an epoxy group, a silane coupling agent having an amino group, a silane coupling agent having a mercapto group, and a silane coupling agent having a (meth)acryloyl group. Examples of the silane coupling agent having an epoxy group include

2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane,

3-glycidoxypropylmethyltrimethoxysilane,

3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropyltriethoxysilane. Examples of the silane coupling agent having an amino group include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane,

3-aminopropyltrimethoxysilane, and 3-aminopropyltriethoxysilane. Examples of the silane coupling agent having a mercapto group include

3-mercaptopropylmethyldimethoxysilane anddithioltriazinepropyltriethoxysilane. Examples of the silane coupling agent having a (meth)acryloyl group include 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane,

3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, and 3-acryloxypropyltrimethoxysilane. Examples of the other effective silane coupling agents include 3-isocyanatopropyltriethoxysilane, a silane coupling agent having a vinyl group, such as vinyltrimethoxysilane, vinyltriethoxysilane, and p-styryltrimethoxysilane,

3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminopropyltrimethoxysilane hydrochloride, tris(trimethoxysilylpropyl) isocyanurate, and a 3-ureidopropyltrialkoxysilane. These compounds may be used alone or as a combination of two or more kinds thereof.

[0050]

[Isocyanate Compound]

The isocyanate compound can impart (introduce) the functional group based on the structure of the isocyanate compound capable of chemically bonding to the primer layer 3 to the material layer through reaction and bonding of the isocyanato group in the isocyanate compound with the hydroxy group existing on the surface of the material layer 2.

[0051]

The isocyanate compound is not particularly limited, and examples thereof include a polyfunctional isocyanate, such as diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HDI), tolylerie diisocyanate (TDI), and isophorone diisocyanate (IPDI), and also include an isocyanate compound having a radically reactive group, such as 2-isocyanatoethyl methacrylate (e.g., "Karenz MOI (registered trademark)", produced by Showa Denko K.K.), 2-isocyanatoethyl acrylate (e.g., "Karenz AOI (registered trademark)" and "Karenz AOI-VM (registered trademark)", produced by Showa Denko K.K.), and l,l-bis(acryloyloxyethyl)ethyl isocyanate (e.g., "Karenz BEI (registered trademark)", produced by Showa Denko K.K.).

[0052]

[Thiol Compound]

The thiol compound can impart (introduce) the functional group based on the structure of the thiol compound capable of chemically bonding to the primer layer to the material layer through reaction and bonding of the mercapto group in the thiol compound with the hydroxy group existing on the surface of the material layer 2.

[0053]

The thiol compound is not particularly limited, and examples thereof include pentaerythritol tetrakis(3-mercaptopropionate) (e.g., "QX40", produced by Mitsubishi Chemical Corporation and "QE-340M", produced by Toray Fine Chemicals Co., Ltd.), an ether based primary thiol (e.g., "Cupcure 3-800", produced by Cognis GmbH), 1,4-bis(3-mercaptobutyryloxy)butane (e.g., "Karenz MT (registered trademark) BD1", produced by Showa Denko K.K.), pentaerythritol tetrakis(3-mercaptobutyrate) (e.g., "Karenz MT (registered trademark) PE1", produced by Showa Denko K.K.), and 1,3,5-tris(3-mercaptobutyloxyethyl)-1,3,5-triazin-2,4,6-(1H, 3H,5H)-trione (e.g., "Karenz MT (registered trademark) NR1", produced by Showa Denko K.K.).

[0054]

<Primer Layer 3>

The primer layer 3 is laminated on the material layer 2 directly or via the functional group-containing layer 4.

[0055]

[In situ Polymerization Composition Layer 31]

As described above, at least one layer of the primer layer is the in situ polymerization composition layer 31 containing a polymer of an in situ polymerization composition.

The in situ polymerization composition layer 31 can be obtained in such a manner that the in situ polymerization composition dissolved in a solvent is coated on the material layer 2 or the functional group-containing layer 4, and after evaporating the solvent, the in situ polymerization composition is polymerized. In the case where the in situ polymerization composition is in a liquid form, the solvent may not be used.

Examples of the solvent include methyl ethyl ketone, methyl isobutyl ketone, acetone, ethyl acetate, toluene, xylene, tetrahydrofuran, and water.

[0056]

The in situ polymerization composition contains a resin having a loss coefficient of 0.30 ε·tanδ or more. With a resin having a loss coefficient of less than 0.30 ε·tanδ, there is a concern that the temperature is not sufficiently increased at the time of welding, and the primer layer cannot be firmly bonded to a material, such as a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber. From this standpoint, the loss coefficient of the resin is preferably 0.32 ε·tanδ or more, and more preferably 0.35 ε·tanδ or more. The upper limit of the loss coefficient is not particularly determined, and is preferably 0.48 ε·tanδ or less, and more preferably 0.40 ε·tanδ or less. The preferred range thereof is 0.30 to 0.48 ε·tanδ, more preferably 0.32 to 0.48 ε·tanδ, further preferably 0.35 to 0.48 ε·tanδ, and still further preferably 0.35 to 0.40 ε·tanδ.

The loss coefficient ( ε·tanδ) can be obtained in such a manner that the relative permeability (ε') and the dielectric tangent (tanδ) at a temperature of 23°C at 1 MHz are measured with a dynamic characteristics tester, and the loss coefficient is calculated from the relative permeability (ε') and the dielectric tangent (tanδ), and is specifically measured in the method described in the examples.

[0057]

Examples of the resin having a loss coefficient of 0.30 ε·tanδ or more include a phenol resin (PF, 0.36 ε·tanδ), a vinyl chloride resin (PVC, 0.315 to 0.45 ε·tanδ), and a polyamide (PA, that has a loss coefficient of 0.30 ε·tanδ or more from a range of 0.16 to 0.611 ε·tanδ). A polyamide that has a loss coefficient of 0.16 or more and less than 0.30 ε·tanδ is not included in the scope of the present invention. From the standpoint of the achievement of the effects of the present invention, among these, at least one kind selected from the group consisting of a vinyl chloride resin, a phenol resin, and a polyamide is preferred, and at least one kind selected from the group consisting of a vinyl chloride resin and a phenol resin is more preferred.

The phenol resin referred herein is a resin that is synthesized from phenol and formaldehyde, and includes a novolac type and a resol type, both of which may be used.

[0058] The in situ polymerization composition preferably contains at least one kind of the following items (1) to (6), more preferably contains the following item

(3), and further preferably contains a combination of a bifunctional epoxy resin and a bifunctional phenol compound.

(1) A combination of a bifunctional isocyanate compound and a bifunctional compound having hydroxy groups

(2) A combination of a bifunctional isocyanate compound and a bifunctional compound having amino groups

(3) A combination of a bifunctional epoxy compound and a bifunctional compound having hydroxy groups

(4) A combination of a bifunctional epoxy compound and a bifunctional carboxy compound

(5) A combination of two kinds of compounds selected from the group consisting of a bifunctional epoxy compound and a bifunctional thiol compound

(6) A monofunctional radically polymerizable monomer

[0059]

The compounds in the items (1) to (6) may have either a loss coefficient of 0.30s ε·tanδ or more or a loss coefficient of less than 0.30 ε·tanδ. In the description herein, a compound that corresponds to the compounds in the items (1) to (6) and also corresponds to the resin having a loss coefficient of 0.30 ε·tanδ or more is deemed to be the compounds in the items (1) to (6).

[0060]

In the item (1), the mixing ratio of the bifunctional isocyanate compound and the bifunctional compound having hydroxy groups is preferably set to provide a molar equivalent ratio of the isocyanate group with respect to the hydroxy group of 0.7 to 1.5, more preferably 0.8 to 1.4, and further preferably 0.9 to 1.3.

In the item (2), the mixing ratio of the bifunctional isocyanate compound and the bifunctional compound having amino groups is preferably set to provide a molar equivalent ratio of the isocyanate group with respect to the amino group of 0.7 to 1.5, more preferably 0.8 to 1.4, and further preferably 0.9 to 1.3.

[0061]

In the item (3), the mixing ratio of the bifunctional epoxy compound and the bifunctional compound having hydroxy groups is preferably set to provide a molar equivalent ratio of the epoxy group with respect to the hydroxy group of 0.7 to 1.5, more preferably 0.8 to 1.4, and further preferably 0.9 to 1.3.

In the item (4), the mixing ratio of the bifunctional epoxy compound and the bifunctional carboxy compound is preferably set to provide a molar equivalent ratio of the epoxy group with respect to the carboxy group of 0.7 to 1.5, more preferably 0.8 to 1.4, and further preferably 0.9 to 1.3.

In the item (5), the mixing ratio of the bifunctional epoxy compound and the bifunctional thiol compound is preferably set to provide a molar equivalent ratio of the epoxy group with respect to the mercapto group of 0.7 to 1.5, more preferably 0.8 to 1.4, and further preferably 0.9 to 1.3.

[0062]

With the in situ polymerization composition layer 31 laminated as the primer layer 3 on the material layer 2, the banding target can be firmly welded to the material layer 2.

[0063]

The primer layer 3 may be constituted by plural layers including the in situ polymerization composition layer 31. In the case where the primer layer 3 is constituted by plural layers, it is preferred that the essential in situ polymerization composition layer 31 is laminated as the outermost layer opposite to the material layer 2. [0064]

The in situ polymerization composition layer 31 is formed of a polymer of the in situ polymerization composition.

The in situ polymerization composition layer 31 may be obtained by mixing a composition containing the resin having a loss coefficient of 0.30 ε·tanδ or more and at least one kind of the items (1) to (5), and subjecting the composition to polyaddition reaction in the presence of a catalyst. Preferred examples of the catalyst used for the polyaddition reaction include a tertiary amine, such as triethylamine and 2,4,6-tris(dimethylaminomethyl)phenol, and a phosphorus compound, such as triphenylphosphine. The polyaddition reaction is preferably performed at ordinary temperature to 200°C for 5 to 120 minutes under heating while depending on the formulation of the composition.

Specifically, for example, the in situ polymerization composition layer 31 may be formed in such a manner that a composition containing the resin having a loss coefficient of 0.30 ε·tanδ or more and at least one kind of the items (1) to (5) is dissolved in a solvent and coated on the material layer 2, and then after evaporating the solvent appropriately, heated to perform the polyaddition reaction, so as to form the in situ polymerization composition layer 31 that is further firmly bonded thereto. The material layer 2 herein includes that having been subjected to the surface treatment and/or the functional group applying treatment.

The in situ polymerization composition layer 31 may also be obtained through radical polymerization reaction of a composition containing the resin having a loss coefficient of 0.30 ε·tanδ or more and the monofunctional radically polymerizable monomer as the item (6). The radical polymerization reaction is preferably performed at ordinary temperature to 200°C for 5 to 90 minutes under heating while depending on the formulation of the composition. In the case where a photocurable monomer is used, the polymerization reaction is preferably performed through irradiation of an ultraviolet ray or visible light.

Specifically, for example, the in situ polymerization composition layer 31 may be formed in such a manner that a composition containing the resin having a loss coefficient of 0.30 ε·tanδ or more and the monofunctional radically polymerizable monomer as the item (6) is dissolved in a solvent and coated on the material layer 2, and then the radical polymerization reaction is performed through heating or irradiation of light, so as to form the in situ polymerization composition layer 31 that is further firmly bonded thereto. The material layer 2 herein includes that having been subjected to the surface treatment and/or the functional group applying treatment.

The proportion of the polymer of the in situ polymerization composition contained in the in situ polymerization composition layer 31 is preferably 80 to 100% by mass, and more preferably 90 to 100% by mass.

[0065]

In the procedure of the polyaddition reaction, the condition for performing the polyaddition reaction, the molecular weight distribution obtained thereby, and the like may vary depending on the functional groups to be combined, and the specific embodiments based on the combinations cannot be comprehensively expressed. Accordingly, it is considered that the direct identification of the in situ polymerization composition layer formed through the polyaddition reaction by the structure or characteristics thereof is impossible or impractical.

[0066]

(Bifunctional Isocyanate Compound)

The bifunctional isocyanate compound is a compound that has two isocyanato groups, and examples thereof include a diisocyanate compound, such as hexamethylene diisocyanate, tetramethylene diisocyanate, dimer acid diisocyanate, 2,4- or 2,6-tolylene diisocyanate (TDI) and a mixture thereof, p-phenylene diisocyanate, xylylene diisocyanate, and diphenylmethane diisocyanate (MDI). Among these, TDI and MDI are preferred from the standpoint of the strength of the primer.

[0067]

(Bifunctional Compound having Hydroxy Groups)

The bifunctional compound having hydroxy groups is a compound that has two hydroxy groups, and examples thereof include a fatty acid glycol and a bifunctional phenol.

Examples of the fatty acid glycol include ethylene glycol, propylene glycol, diethylene glycol, and 1,6-hexanediol. Examples of the bifunctional phenol include a bisphenol compound, such as bisphenol A, bisphenol F, and bisphenol S.

Propylene glycol, diethylene glycol, and the like are preferred from the standpoint of the toughness of the primer.

In the item (3), the bifunctional compound having hydroxy groups to be combined with the bifunctional epoxy compound is preferably the bifunctional phenol, and more preferably the bisphenol compound. [0068]

(Bifunctional Compound having Amino Groups)

The bifunctional compound having amino groups is a compound that has . two amino groups, and examples thereof include a bifunctional aliphatic diamine and a bifunctional aromatic diamine. Examples of the aliphatic diamine include ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 1,4-diaminobutane,

1 , 6-hexamethylenediamine, 2,5-dimethyl-2,5-hexanediamine,

2,2,4-trimethylhexamethylenediamine, isophoronediamine, bis(4-amino-3-methylcyclohexyl)methane, 1,3-diaminocyclohexane, and N-aminoethylpiperazine. Examples of the aromatic diamine include diaminodiphenylmethane and diaminodiphenylpropane. Among these, 1,3-propanediamine, 1,4-diaminobutane, and 1, 6-hexamethylenediamine are preferred from the standpoint of the toughness of the primer.

[0069]

(Bifunctional Epoxy Compound)

The bifunctional epoxy compound is a compound that has two epoxy groups in one molecule. Examples thereof include an aromatic epoxy resin, such as a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, a biphenol type epoxy resin, and a naphthalene type bifunctional epoxy resin, and an aliphatic epoxy compound, such as 1,6-hexanediol glycidyl ether.

These compounds may be used alone or as a combination of two or more kinds thereof.

Specific examples thereof include "jER (registered trademark) 828", "jER (registered trademark) 834", "jER (registered trademark) 1001", "jER (registered trademark) 1004", and "jER (registered trademark) YX-4000", produced by Mitsubishi Chemical Corporation. In addition, an epoxy compound having an atypical structure that is bifunctional may also be used. These compounds may be used alone or as a combination of two or more kinds thereof. [0070]

(Bifunctional Carboxy Compound)

It suffices that the bifunctional carboxy compound is a compound that has two carboxy groups, and examples thereof include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid, terephthalic acid, adipic acid, and the like are preferred from the standpoint of the strength and the toughness of the primer.

[0071]

(Bifunctional Thiol Compound)

The bifunctional thiol compound is a compound that has two mercapto groups in the molecule, and examples thereof include a bifunctional secondary thiol compound, such as 1,4-bis(3-mercaptobutylyloxy)butane (e.g., "Karenz MT (registered trademark) BD1", produced by Showa Denko K.K).

[0072]

(Monofunctional Radically Polymerizable Monomer)

The monofunctional radically polymerizable monomer is a monomer that has one ethylenic unsaturated bond. Examples thereof include a styrene based monomer, such as styrene monomer, α-, ο-, m-, and p-alkyl, nitro, cyano, amido, and ester derivatives of styrene, chlorostyrene, vinyltoluene, and divinylbenzene; and a (meth)acrylate ester compound, such as ethyl (meth)acrylate, methyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, hexyl

(meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, dodecyl

(meth)acrylate, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofuryl (meth)acrylate, acetoacetoxyethyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, and glycidyl (meth)acrylate. These compounds may be used alone or as a combination of two or more kinds thereof. Among these, one kind or a combination of two or more kinds of styrene, methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and phenoxyethyl (meth)acrylate is preferred from the standpoint of the strength and the toughness of the primer.

For sufficiently performing the radical polymerization reaction to form the target primer layer, a solvent and an additive, such as a colorant, may be contained. In this case, the monofunctional radically polymerizable monomer is preferably a major component in the components except for the solvent contained in a radically polymerizable composition. The major component herein means that the content of the monofunctional radically polymerizable monomer is 50 to 100% by mass. The content is preferably 60% by mass or more, and more preferably 80% by mass or more.

As a polymerization initiator for the radical polymerization reaction, for example, an organic peroxide compound, a photoinitiator, and the like having been known may be preferably used, An ordinary temperature radical polymerization initiator having a combination of an organic peroxide compound and a cobalt salt or an amine compound may also be used. Examples of the organic peroxide compound include compounds classified into a ketone peroxide, a peroxyketal, a hydroperoxide, a diallyl peroxide, a diacyl peroxide, a peroxyester, and a peroxydicarbonate. The photoinitiator used is preferably a compound capable of initiating the polymerization with an ultraviolet ray to visible light.

The radical polymerization reaction is preferably performed at ordinary temperature to 200°C for 5 to 90 minutes under heating while depending on the kinds of the reaction compounds and the like. In the case of the photoinitiator, the polymerization reaction may be performed through irradiation of an ultraviolet ray or visible light.

[0073]

[Thermosetting Resin Layer 32]

In the case where the primer layer 3 is constituted by plural layers including the in situ polymerization composition layer 31, a thermosetting resin layer 32 formed of a cured product of a composition containing a thermosetting resin may be provided below the in situ polymerization composition layer 31, as shown in Fig. 3.

The composition containing, a thermosetting resin may contain a solvent and an additive, such as a colorant, for sufficiently performing the curing reaction of the thermosetting resin to form the target primer layer. In this case, the thermosetting resin is preferably a major component in the components except for the solvent contained in the thermosetting resin composition, The major component herein means that the content of the thermosetting resin is 40% by mass or more. The content is preferably 60% by mass or more, more preferably

70% by mass or more, and further preferably 80% by mass or more. [0074]

Examples of the thermosetting resin include a urethane resin, an epoxy resin, a vinyl ester resin, and an unsaturated polyester resin.

The thermosetting resin layer 32 may be formed with only one kind of the resins or with a mixture of two or more kinds thereof. In alternative, it is possible that the thermosetting resin layer 32 is constituted by plural layers, and the layers are formed of compositions containing thermosetting resins of different kinds. [0075]

The coating method for forming the thermosetting resin layer 32 with the composition containing a monomer of the thermosetting resin is not particularly limited, and examples thereof include a spray coating method and a dipping method.

[0076]

The thermosetting resin referred in the present embodiment means a wide range of resins that are crosslinked and cured, and encompasses not only a thermally curable type, but also an ordinary temperature curable type and a photocurable type. The photocurable type may be cured in a short period of time through irradiation of visible light or an ultraviolet ray. The photocurable type may be used in combination with the thermally curable type and/or the ordinary temperature curable type. Examples of the photocurable type include a vinyl ester resin, such as "Ripoxy (registered trademark) LC-760" and "Ripoxy (registered trademark) LC-720", produced by Showa Denko K.K.

[0077]

(Urethane Resin)

The urethane resin is generally a resin that is obtained through reaction of an isocyanato group of an isocyanate compound and a hydroxy group of a polyol compound, and is preferably a urethane resin corresponding to a resin defined as the "paint containing 10% by weight or more (non-volatile vehicle basis) of polyisocyanate" in ASTM D16. The urethane resin may be a one-component type or a two-component type.

[0078]

Examples of the one-component urethane resin include an oil modified type (cured through oxidation polymerization of an unsaturated fatty acid group), a moisture curing type (cured through reaction of an isocyanato group and water in the air), a block type (cured through reaction of an isocyanato group regenerated by dissociation of an block agent under heating and a hydroxy group), and a lacquer type (cured by drying through evaporation of a solvent). Among these, a moisture curing type one-component urethane resin is preferably used from the standpoint of the handleability and the like. Specific examples thereof include "UM-50P", produced by Showa Denko K.K.

[0079]

Examples of the two-component urethane resin include a catalytic curing type (cured through reaction of an isocyanato group and water in the air or the like in the presence of a catalyst) and a polyol curing type (cured through reaction of an isocyanato group and a hydroxy group of a polyol compound).

[0080]

Examples of the polyol compound in the polyol curing type include a polyester polyol, a polyether polyol, and a phenol resin.

Examples of the isocyanate compound having an isocyanato group in the polyol curing type include an aliphatic isocyanate, such as hexamethylene diisocyanate (HDI), tetramethylene diisocyanate, and dimer acid diisocyanate; an aromatic isocyanate, such as 2,4- or 2,6-tolylene diisocyanate (TDI) and a mixture thereof, p-phenylene diisocyanate, xylylene diisocyanate, and diphenylmethane diisocyanate (MDI) and polymeric MDI, which is a polynuclear mixture thereof; and an alicyclic isocyanate, such as isophorone diisocyanate (IPDI).

The mixing ratio of the polyol compound and the isocyanate compound in the polyol curing type two-component urethane resin is preferably such a value that provides a hydroxy group/isocyanato group molar equivalent ratio in a range of 0.7 to 1.5.

[0081]

Examples of the urethanation catalyst used in the two-component urethane resin include an amine based catalyst, such as triethylenediamine, tetramethylguanidine, Ν,Ν,Ν',Ν'-tetramethylhexane-1, 6-diamine, dimethyl ether amine, N,N,N',N",N"-pentamethyldipropylenetriamine, N -methylmorpholine, bis(2-dimethylaminoethyl) ether, and dimethylaminoethoxyethanoltriethylamine; and an organic tin based catalyst, such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin thiocarboxylate, and dibutyltin dimaleate.

In the polyol curing type, the urethanation catalyst is generally preferably mixed in an amount of 0.01 to 10 parts by mass per 100 parts by mass of the polyol compound.

[0082]

(Epoxy Resin)

The epoxy resin is a resin that has at least two epoxy groups in one molecule.

Examples of the prepolymer of the epoxy resin before curing include an ether based bisphenol type epoxy resin, a novolac type epoxy resin, a polyphenol type epoxy resin, an aliphatic type epoxy resin, an ester based aromatic epoxy resin, an alicyclic epoxy resin, and an ether-ester based epoxy resin, and among these, a bisphenol A type epoxy resin is preferably used. These materials may be used alone or as a combination of two or more kinds thereof.

Specific examples of the bisphenol A type epoxy resin include "jER (registered trademark) 828" and "jER (registered trademark) 1001", produced by Mitsubishi Chemical Corporation.

Specific examples of the novolac type epoxy resin include "D.E.N. (registered trademark) 438", produced by The Dow Chemical Company.

[0083]

Examples of the curing agent used for the epoxy resin include known curing agents, such as an aliphatic amine, an aromatic amine, an acid anhydride, a phenol resin, a thiol compound, an imidazole compound, and a cationic catalyst. The curing agent that is used in combination with a long chain aliphatic amine and/or a thiol compound can provide an effect of large elongation arid excellent impact resistance.

Specific examples of the thiol compound include the same compounds as exemplified as the thiol compound for forming the functional group-containing layer. Among the compounds, pentaerythritol tetrakis(3-mercaptobutyrate) (e.g., "Karenz MT (registered trademark) PEI", produced by Showa Denko K.K.) is preferred from the standpoint of the elongation and impact resistance.

[0084]

(Vinyl Ester Resin)

The vinyl ester resin is a vinyl ester compound dissolved in a polymerizable monomer (such as styrene). The . vinyl ester resin may also be referred to as an epoxy (meth)acrylate resin, but herein encompasses a urethane (meth)acrylate resin.

Examples of the vinyl ester resin include those described in "Polyester Jushi Handbook" (Polyester Resin Handbook) (published by Nikkan Kogyo Shimbun, Ltd., 1988), "Toryo Yougo Jiten" (Paint Terminological Dictionary) (published by Japan Society of Colour Material, 1993), and the like, and specific examples thereof include "Ripoxy (registered trademark) R-802", "Ripoxy (registered trademark) R-804", and "Ripoxy (registered trademark) R-806", produced by Showa Denko K.K.

[0085]

Examples of the urethane (meth)acrylate resin include a radically polymerizable unsaturated group-containing oligomer obtained in such a manner that an isocyanate compound and a polyol compound are reacted, and then a hydroxy group-containing (meth)acrylic monomer (and depending on necessity a hydroxy group-containing allyl ether monomer) is further reacted. Specific examples thereof include "Ripoxy (registered trademark) R-6545", produced by Showa Denko K.K.

[0086]

The vinyl ester resin can be cured through radical polymerization under heating in the presence of a catalyst, such as an organic peroxide.

The organic peroxide is not particularly limited, and examples thereof include a ketone peroxide compound, a peroxyketal compound, a hydroperoxide compound, a diallyl peroxide compound, a diacyl peroxide compound, a peroxyester compound, and a peroxydicarbonate compound. Curing can be performed at ordinary temperature by combining these compounds with a cobalt metal salt or the like.

The cobalt metal salt is not particularly limited, and examples thereof include cobalt naphthenate, cobalt octylate, and cobalt hydroxide. Among these, cobalt naphthenate and/or cobalt octylate are preferred.

[0087]

(Unsaturated Polyester Resin)

The unsaturated polyester resin is a condensation product (unsaturated polyester) formed through esterification reaction of a polyol compound and an unsaturated polybasic acid (and depending on necessity a saturated polybasic acid) dissolved in a polymerizable monomer (such as styrene).

Examples of the unsaturated polyester resin include those described in "Polyester Jushi Handbook" (Polyester Resin Handbook) (published by Nikkan Kogyo Shimbun, Ltd., 1988), "Toryo Yougo Jiten" (Paint Terminological Dictionary) (published by Japan Society of Colour Material, 1993), and the like, and specific examples thereof include "Rigolac (registered trademark)", produced by Showa Denko K.K.

[0088]

The unsaturated polyester resin can be cured through radical polymerization under heating in the presence of the similar catalyst as for the vinyl ester resin.

[0089] [Function of Primer Layer 3]

The primer layer 3 provides excellent adhesiveness to the material layer

2.

The primer layer 3 imparts excellent bondability to another material (bonding material) as a bonding target. The available period of the bondability thereof is a long period of time exceeding several months.

The primer layer 3 protects the surface of the material layer 2, and thereby attachment of contamination and deterioration, such as oxidation, can be suppressed.

[0090]

[Bonded Article 5]

A bonded article 5 of one embodiment includes a material (bonding material) 6, which is at least one kind selected from the group consisting of a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber, welded to the primer layer of the material with a primer 1 as the material to be bonded, as shown in Fig. 4.

The welding may be performed by various methods in terms of the method of heating the primer layer 3, arid specific examples thereof include high frequency welding, ultrasonic welding, vibration welding, thermal welding, hot air welding, induction welding, and injection welding. Among these, high frequency welding is preferred.

[0091]

The high frequency welding is a method of welding by melting the material from the interior thereof through dielectric heating with a high frequency wave. Examples of the equipment used for the high frequency welding include a high frequency heating equipment having an electric power source and a heating coil (high frequency bar) generating a strong high frequency electric field. Specific examples thereof include High-frequency Welder, produced by Yamamoto Vinita Co., Ltd. The heating coil of the high frequency heating equipment has a coil disposed thereinside, and a strong high frequency electric field is generated by applying an electric current to the coil.

Examples of the condition of the high frequency wave in the high frequency welding include an, output power of 3 to 100 kW and a generation frequency of a low radio frequency of 13.56 to 40.46 MHz.

[0092] The bonding material 6 may include a material layer formed of a material, which is at least one kind selected from the group consisting of a metal, glass, ceramics, fiber-reinforced plastics, a resin, and rubber, having on one surface thereof one layer or plural layer of a primer layer, and at least one layer of the primer layer may be an in situ polymerization composition layer formed of a polymer of an in situ polymerization composition containing a resin having a loss coefficient of 0.30 ε·tanδ or more.

In a bonded article 5 of another embodiment, as shown in Fig. 5, a bonding material 6 is constituted by a material with a primer 7 having one layer or plural layer of a primer layer 9 laminated on a material layer 8, in which at least one of the primer layer 9 is an in situ polymerization composition layer formed of a polymer of an in situ polymerization composition, and the primer layer 9 of the material with a primer 7 and the primer layer 3 of the material with a primer 1 as the material to be bonded are welded to each other. The material with a primer 7 may have a functional group-containing layer 10 between the material layer 8 and the primer layer 9, as similar to the material with a primer 1.

[0093]

The thickness (thickness after drying) of the primer layer is preferably 1 μm to 10 mm froin the standpoint of the achievement of the excellent bonding strength to the bonding target and the standpoint of the suppression of the thermal deformation of the bonded article caused by the difference in thermal expansion coefficient between the materials of different kinds, while depending on the material of the bonding target and the contact area of the bonded portion. The thickness thereof is more preferably 10 μm to 8 mm, and further preferably 50 μm to 5 mm. In the case where the primer layer includes plural layers, the thickness (thickness after drying) of the primer layer means the total thickness of the layers.

[0094]

Examples of the method for producing the bonded article 5 include a method of welding the primer layer 3 of the material with a primer 1 to the bonding material 6 through at least one kind selected from the group consisting of high frequency welding, ultrasonic welding, vibration welding, thermal welding, hot air welding, induction welding, and injection welding.

[0095]

[In situ Polymerization Composition] The in situ polymerization composition of the present embodiment contains a resin having a loss coefficient of 0.30 ε·tanδ or more and at least one kind of the items (1) to (6), and is used for a primer layer having a thermoplastic resin structure.

[0096]

The resin having a loss coefficient of 0.30 ε·tanδ or more and the compounds shown in the items (1) to (6) may all be those described in the section [Material with Primer].

[0097]

The content of the resin having a loss coefficient of 0.30 ε·tanδ or more contained in the total amount of the in situ polymerization composition is preferably 0.5 to 50% by mass, more preferably 1 to 30% by mass, and further preferably 2 to 15% by mass, from the standpoint of the weldability of the primer. [0098]

The total content of the resin having a loss coefficient of 0.30 ε·tanδ or more and at least one kind of the compounds shown in the items (1) to (6) contained in the total amount of the in situ polymerization composition is preferably 80 to 100% by mass, and more preferably 90 to 100% by mass.

Examples

[0099]

Specific examples of the present invention will be described below, but the present invention is not limited to the examples. The ordinary temperature in the examples is 23°C.

[0100]

[Material for Test Piece (Inorganic Material and FRP)]

The materials (18 mm × 45 mm) shown in Table 1 were prepared as materials for a test piece.

[0101]

<Surface Treatment (Sanding Treatment)>

The surface of the material shown in Table 1, i.e., the steel, the CFRP, the copper, the ceramics, or the GFRP, was ground with #1000 sandpaper, and then cleaned and degreased with acetone.

[0102]

<Surface Treatment (Chemical Conversion Treatment)> Aluminum (A6063) shown in Table 1 was immersed in a sodium hydroxide aqueous solution having a concentration of 5% by mass for 1.5 minutes, and then neutralized with a nitric acid aqueous solution having a concentration of 5% by mass.

[0103]

<Functional Group Applying Treatment (Silane Coupling Agent Treatment)>

The aluminum having been subjected to the chemical conversion treatment, the CFRP having been subjected to the sanding treatment, the copper having been subjected to the sanding treatment, the ceramics having been subjected to the sanding treatment, the glass shown in Table 1, the copper foil shown in Table 1, and the GFRP having been subjected to the sanding treatment each were immersed in a silane coupling agent-containing solution obtained by dissolving 2 g of 3-aminopropyltrimethoxysilane (a silane coupling agent, KBM-903, produced by Shin-Etsu Silicone Co., Ltd.) in 1,000 g of industrial ethanol at 70°C for 20 minutes. The materials were taken out from the solution and then dried to form a functional group (amino group) layer.

[0104] Table 1 [0105]

[Material for Test Piece (Thermoplastic Resin)]

Test pieces for tensile test of a PA6 resin, a PPS resin, a PEI resin, a PC resin, and a PBT resin (25 mm × 100 mm × 1 mm) were obtained with an injection molding machine (SE100V, produced by Sumitomo Heavy Industries, Ltd.) under the condition shown in Table 2.

[0106] Table 2 [0107]

[Material for Test Piece (Film and Thin Film Glass)]

A film and thin film glass shown in Table 3 were prepared.

[0108] Table 3

[0109]

<Surface Treatment (Corona Discharge Treatment)>

The acrylic resin film shown in Table 3 was subjected to a corona discharge treatment.

[0110]

<Functional Group Applying Treatment (Silane Coupling Agent Treatment)>

The ultrathin sheet glass and the acrylic resin film having been subjected to the corona discharge treatment shown in Table 3 each were immersed in a silane coupling agent-containing solution obtained by dissolving 2 g of 3-aminopropyltrimethoxysilane (a silane coupling agent, KBM-903, produced by Shin-Etsu Silicone Co., Ltd.) in 1,000 g of industrial ethanol at 70°C for 20 minutes. The materials were taken out from the solution and then dried to form a functional group (amino group) layer.

[0111]

<Preparation of In situ Polymerization Composition 1 for forming Primer Layer> 100 g of a bifunctional epoxy resin ("jER (registered trademark) 1007", produced by Mitsubishi Chemical Corporation, loss coefficient: 0.20 ε·tanδ), 3.1 g of bisphenol S, 2.6 g of a novolac type phenol resin (Shonol BRG-556, produced by Aica Kogyo Co., Ltd., loss coefficient: 0.36 ε·tanδ), and 0.4 g of triphenylphosphine were dissolved in 197 g of methyl ethyl ketone, so as to prepare an in situ polymerization composition 1 (i.e., a phenol resin-containing in situ polymerization type thermoplastic epoxy resin composition).

[0112]

The loss coefficient ( ε·tanδ) was obtained in such a manner that a test piece of 20 mm × 20 mm × 2 mm was measured for the relative permeability (ε') and the dielectric tangent (tanδ) at a temperature of 23°C at 1 MHz with a dynamic characteristics tester (Impedance-Material Analyzer, Model No. 4291B, produced by Hewlett-Packard Japan, Ltd.), and the loss coefficient was calculated from the relative permeability (ε') and the dielectric tangent (tanδ).

The test piece of the bifunctional epoxy resin (jER (registered trademark) 1007) was produced in such a manner that jER (registered trademark) 1007 was melted at 200°C and then injected into a metal mold of 20 mm × 20 mm × 2 mm, and was then cooled to room temperature (25°C), followed by demolding. The test piece of the novolac type phenol resin (Shonol BRG-556) was produced in the same manner as in the test piece of jER (registered trademark) 1007 except that jER (registered trademark) 1007 was changed to Shonol BRG-556.

The test piece of the vinyl chloride resin (ZEST 700L) was produced in such a manner that ZEST 700L was melted at 280°C and then injected into a metal mold of 20 mm × 20 mm × 2 mm, and was then cooled to room temperature (25°C), followed by demolding. The test piece of the polyamide resin (Amilan TR-1) was produced in the same manner as in the test piece of the vinyl chloride resin except that ZEST 700L was changed to Amilan TR-1.

The test piece of jER (registered trademark) 828 was produced in such a manner that 67 g of bisphenol S (BPS) was mixed in 100 g of jER (registered trademark) 828, which were dissolved while stirring at 100°C for 1 hour to prepare a solution, to which 0.67 g of triphenylphosphine (TPP) was added, and then the solution was injected into a metal mold of 20 mm × 20 mm × 2 mm, cured at 150°C over 1 hour, and then cooled to room temperature (25°C), followed by demolding.

[0113]

<Preparation of In situ Polymerization Composition 2 for forming Primer Layer> 100 g of diphenylmethane diisocyanate, 158 g of diaminodiphenylmethane, and 40 g of a vinyl chloride resin ("ZEST 700L", produced by Shindai-ichi Vinyl Corporation, loss coefficient: 0.38 ε·tanδ) were dissolved in 480 g of acetone, so as to prepare an in situ polymerization composition 2 (i.e., a vinyl chloride resin-containing in situ polymerization type polyurea resin composition).

[0114]

<Preparation of In situ Polymerization Composition 3 for forming Primer Layer>

100 g of diphenylmethane diisocyanate, 60.8 g of propylene glycol, and 20 g of a polyamide (fine particle nylon 6 "Amilan TR-1", produced by Toray Industries, Ltd., average particle diameter: 13 μm, loss coefficient: 0.35 ε·tanδ) were dissolved in 480 g of acetone, so as to prepare an in situ polymerization composition 3 (i.e., a polyamide-containing in situ polymerization type polyurethane resin composition).

[0115]

<Formation of Primer Layer>

The in situ polymerization composition 1 was coated by a spraying method to a thickness after drying of 20 μm on one surface of each of the steel shown in Table 1 (hereinafter referred to as a non-treated steel), the steel having been subjected to the sanding treatment (hereinafter referred to as a sanding steel), the aluminum having been subjected to the silane coupling agent treatment (hereinafter referred to as silane coupling agent treated aluminum 1), the CFRP shown in Table 1 (hereinafter referred to as non-treated CFRP), the copper shown in Table 1 (hereinafter referred to as non-treated copper), and the copper having been subjected to the silane coupling agent treatment (hereinafter referred to as silane coupling agent treated copper). After evaporating the solvent by allowing to stand in the air at ordinary temperature for 30 minutes, the polyaddition reaction was performed by allowing to stand in a furnace at 150°C for 30 minutes, followed by cooling to ordinary temperature, so as to form a primer layer 1 formed of a cured product of the in situ polymerization composition 1.

[0116]

The in situ polymerization composition 2 was coated by a spraying method to a thickness after drying of 20 μm on one surface of each of the aluminum shown in Table 1 (hereinafter referred to as non-treated aluminum), the silane coupling agent treated aluminum 1, the CFRP having been subjected to the silane coupling agent treatment (hereinafter referred to as silane coupling agent treated CFRP 1), the silane coupling agent treated copper, the glass having been subjected to the silane coupling agent treatment (hereinafter referred to as silane coupling agent treated glass), the ceramics having been subjected to the silane coupling agent treatment (hereinafter referred to as silane coupling agent treated ceramics), and the GFRP having been subjected to the silane coupling agent treatment (hereinafter referred to as silane coupling agent treated GFRP). After evaporating the solvent by allowing to stand in the air at ordinary temperature for 30 minutes, the polyaddition reaction was performed by allowing to stand in a furnace at 120°C for 10 minutes, followed by cooling to ordinary temperature, so as to form a primer layer 2 formed of a cured product of the in situ polymerization composition 2.

[0117]

For the PEI and the PBT (GF: 30% by mass) shown in Table 2, the in situ polymerization composition 1 was coated by a spraying method to a thickness after drying of 20 μm thereon. After evaporating the solvent by allowing to stand in the air at ordinary temperature for 30 minutes, the polyaddition reaction was performed by allowing to stand in a furnace at 120°C for 10 minutes, followed by cooling to ordinary temperature, so as to form a primer layer 1 formed of a cured product of the in situ polymerization composition 1.

[0118]

For the PC, the PA6 (GF: 30% by mass), and the PPS shown in Table 2, the in situ polymerization composition 2 was coated by a spraying method to a , thickness after drying of 20 μm thereon. After evaporating the solvent by allowing to stand in the air at ordinary temperature for 30 minutes, the polyaddition reaction was performed by allowing to stand in a furnace at 120°C for 10 minutes, followed by cooling to ordinary temperature, so as to form a primer layer 2 formed of a cured product of the in situ polymerization composition 2. [0119]

The in situ polymerization composition 3 was coated by a spraying method to a thickness after drying of 2 μm on one surface of each of the silane coupling agent treated aluminum 1, the copper foil having been subjected to the silane coupling agent treatment (hereinafter referred to as a silane coupling agent treated copper foil), the ultrathin sheet glass having been subjected to the silane coupling agent treatment (hereinafter referred to as a silane coupling agent treated ultrathin sheet glass), and the acrylic resin film having been subjected to the silane coupling agent treatment (hereinafter referred to as a silane coupling agent treated acrylic resin film). After evaporating the solvent by allowing to stand in the air at ordinary temperature for 30 minutes, the polyaddition reaction was performed by allowing to stand in a furnace at 100°C for 20 minutes, followed by cooling to ordinary temperature, so as to form a primer layer 3 formed of a cured product of the in situ polymerization composition 3.

[0120]

The surface having the primer layer formed thereon is referred to as a primer surface, and the surface having no primer layer formed thereon is referred to as a non-primer surface. In Tables 4 and 5 below, the primer surface is referred to as (yes), and the non-primer surface is referred to as (no).

[0121]

[Example 1]

(High Frequency Welding)

The primer layer 1 surface of the sanding steel and the primer layer 1 surface of the sanding steel were lapped on each other to form a bonding part of 18 mm x 10 mm, and in this state, high frequency welding was performed with High-frequency Welder, PLASEST-8 × XD, produced by Yamamoto Vinita Co., Ltd., under condition of a high frequency output power of 8 kW, an oscillation frequency of 40.46 MHz, and a welding time of 1.5 seconds, so as to provide a test piece 1 (i.e., a steel-steel bonded article). The bonded part referred herein means the portion where the test piece materials were lapped on each other.

[0122]

(Tensile Shear Strength)

The test piece 1 was allowed to stand at ordinary temperature (23°C) for 1 day and then measured for the bonding strength by performing a tensile shear strength test according to JIS K6850:1999 with a tensile tester (Universal Testing Machine Autograph "AG-IS", produced by Shimadzu Corporation, load cell: 10 kN, tensile rate: 5 mm /min, temperature: 23°C, 50%RH). The measurement results are shown in Table 4 below.

[0123]

[Examples 2 to 13]

Tensile shear test pieces were prepared with the combinations of the material to be bonded and the bonding target shown in Table 4, and the tensile shear strength test was performed, in the same manner as in Example 1. The measurement results are shown in Table 4 below.

[0124] Table 4 [0125]

[Comparative Example 1] <Preparation of Comparative In situ Polymerization Composition 1>

100 g of a bifunctional epoxy resin ("jER (registered trademark) 828", produced by Mitsubishi Chemical Corporation, loss coefficient: 0.20 ε·tanδ), 80.9 g of 1,4-bis(3-mercaptobutyryloxy)butane ("Karenz MT (registered trademark) BD1", produced by Showa Denko K.K.), and 7.2 g of 2,4,6-tris(dimethylaminomethyl)phenol (produced by Fujifilm Wako Pure Chemical Corporation) were subjected to polyaddition reaction at room temperature (25°C) for 24 hours, and the resulting polymer was dissolved in 197 g of methyl ethyl ketone, so as to prepare a comparative in situ polymerization composition 1.

[0126]

(Formation of Primer Layer)

The comparative in situ polymerization composition 1 was coated by a spraying method to a thickness after drying of 20 μm on one surface of the sanding steel. The solvent was evaporated by allowing to stand in the air at ordinary temperature for 30 minutes, so as to form a primer layer Cl.

[0127]

(High Frequency Welding)

A comparative test piece 1 (i.e., a steel-steel bonded article) was obtained in the same manner as in Example 1 except that the primer layer Cl surface of the sanding steel and the primer layer Cl surface of the sanding steel were lapped on each other to form a bonding part of 18 mm × 10 mm.

[0128]

(Tensile Shear Strength)

The comparative test piece 1 was subjected to the tensile shear strength test in the same manner as in Example 1. The measurement results are shown in Table 5 below.

[0129]

[Comparative Example 2]

<Preparation of Comparative In situ Polymerization Composition 2>

100 g of diphenylmethane diisocyanate, 60.8 g of propylene glycol, and 0.16 g of 2,4,6-tris(dimethylaminomethyl)phenol were subjected to polyaddition reaction at room temperature (25°C) for 24 hours, and the resulting polymer was dissolved in 299 g of acetone, so as to prepare a comparative in situ polymerization composition 2.

[0130]

(Formation of Primer Layer)

The comparative in situ polymerization composition 2 was coated by a spraying method to a thickness after drying of 20 μm on one surface of each of the silane coupling agent treated copper and the silane coupling agent treated aluminum 1. The solvent was evaporated by allowing to stand in the air at ordinary temperature for 30 minutes, so as to form a primer layer C2.

[0131]

(High Frequency Welding)

A comparative test piece 2 (i.e., a copper-aluminum bonded article) was obtained in the same manner as in Example 1 except that the primer layer C2 surface of the silane coupling agent treated copper and the primer layer C2 surface of the silane coupling agent treated aluminum 1 were lapped on each other to form a bonding part of 18 mm × 10 mm.

[0132]

(Tensile Shear Strength)

The comparative test piece 2 was subjected to the tensile shear strength test in. the same manner as in Example 1. The measurement results are shown in Table 5 below.

[0133]

[Comparative Example 3]

(Preparation of Comparative In situ Polymerization Composition 3)

100 g of diphenylmethane diisocyanate and 60.8 g of propylene glycol were subjected to polyaddition reaction at room temperature (25°C) for 24 hours, and the resulting polymer was dissolved in 480 g of acetone, so as to prepare a comparative in situ polymerization composition 3.

[0134]

(Formation of Primer Layer)

The comparative in situ polymerization composition 3 was coated by a spraying method to a thickness after drying of 20 μm on one surface of each of the silane coupling agent treated ceramics and the silane coupling agent treated GFRP. The solvent was evaporated by allowing to stand in the air at ordinary temperature for 30 minutes, so as to form a primer layer C3. [0135]

(High Frequency Welding)

A comparative test piece 3 (i.e., a ceramics-GFRP bonded article) was obtained in the same manner as in Example 1 except that the primer layer C3 surface of the silane coupling agent treated ceramics and the primer layer C3 surface of the silane coupling agent treated GFRP were lapped on each other to form a bonding part of 18 mm × 10 mm;

[0136]

(Tensile Shear Strength)

The comparative test piece 3 was subjected to the tensile shear strength test in the same manner as in Example 1. The measurement results are shown in Table 5 below.

[0137]

[Comparative Example 4]

(Formation of Primer Layer)

The solvent of the in situ polymerization composition 1 was evaporated in a flask, and the composition was then retained at 150°C for 30 minutes to provide a thermoplastic epoxy resin (hereinafter referred to as a polymerized thermoplastic epoxy resin). After cooling, acetone was added thereto make an amount thereof of 65% by mass, the resin was completely dissolved therein, so as to provide a polymerized thermoplastic epoxy resin solution.

The polymerized thermoplastic epoxy resin solution was coated by a spraying method to a thickness after drying of 20 μm on one surface of each of the silane coupling agent treated aluminum 1 and the silane coupling agent treated copper, The solution was dried at 50°C for 5 hours, so as to prepare a polymerized primer layer. [0138]

(High Frequency Welding)

A comparative test piece 4 (i.e., an aluminum-copper bonded article) was obtained in the same manner as in Example 1 except that the polymerized primer layer surface of the silane coupling agent treated aluminum 1 and the polymerized primer layer surface of the silane coupling agent treated copper were lapped on each other to form a bonding part of 18 mm × 10 mm.

[0139]

(Tensile Shear Strength) The comparative test piece 4 was subjected to the tensile shear strength test in the same manner as in Example 1. The measurement results are shown in Table 5 below.

[0140]

[Comparative Example 5]

(Preparation of Comparative In situ Polymerization Composition 4)

100 g of a bifunctional epoxy resin ("jER (registered trademark) 1007", produced by Mitsubishi Chemical Corporation, loss coefficient: 0.20 ε·tanδ), 3.1 g of bisphenol S, and 0.4 g of triphenylphosphine were dissolved in 197 g of methyl ethyl ketone, so as to prepare a comparative in situ polymerization composition 4. [0141]

(Formation of Primer Layer)

The comparative in situ polymerization composition 4 was coated by a spraying method to a thickness after drying of 20 μm on one surface of the sanding steel. The solvent was evaporated by allowing to stand in the air at ordinary temperature for 30 minutes, so as to form a primer layer C4.

[0142]

(High Frequency Welding)

A comparative test piece 5 (i.e., a steel-steel bonded article) was obtained in the same manner as in Example 1 except that the primer layer C4 surface of the sanding steel and the primer layer C4 surface of the sanding steel were lapped on each other to form a bonding part of 18 mm × 10 mm.

[0143]

(Tensile Shear Strength)

The comparative test piece 5 was subjected to the tensile shear strength test in the same manner as in Example 1. The measurement results are shown in Table 5 below.

[0144]

[Comparative Example 6]

(Preparation of Comparative In situ Polymerization Composition 5)

100 g of diphenylmethane diisocyanate and 158 g of diaminodiphenylmethane were dissolved in 480 g of acetone, so as to prepare a comparative in situ polymerization composition 5.

[0145]

(Formation of Primer Layer) The comparative in situ polymerization composition 5 was coated by a spraying method to a thickness after drying of 20 μm on one surface of each of the non-treated aluminum and the PC shown in Table 2. The solvent was evaporated by allowing to stand in the air at ordinary temperature for 30 minutes, so as to form a primer layer C5.

[0146]

(High Frequency Welding)

A comparative test piece 6 (i.e., an aluminum-PC bonded article) was obtained in the same manner as in Example 1 except that the primer layer C5 surface of the non-treated aluminum and the primer layer C5 surface of the PC were lapped on each other to form a bonding part of 18 mm × 10 mm.

[0147]

(Tensile Shear Strength)

The comparative test piece 6 was subjected to the tensile shear strength test in the same manner as in Example 1. The measurement results are shown in Table 5 below.

[0148] Table 5 [0149]

[Example 14]

(High Frequency Welding)

A test piece 14 (i.e., aluminum with a copper foil, which was an aluminum-copper foil bonded article) of Example 14 was obtained in the same manner as in Example 1 except that the primer layer 3 surface of the silane coupling agent treated aluminum 1 and the primer layer 3 surface of the silane coupling agent treated copper foil were lapped on each other to form a bonding part of 10 mm × 40 mm.

[0150]

(Peel Test)

The test piece 14 was measured for the peel strength according to JIS C6481:1996 in such a manner that the edge of the copper foil having a width of 18 mm was held and pulled in the 90° direction at a pulling rate of 50 mm/min to a peel length of 40 mm. The measurement results are shown in Table 6 below. [0151]

[Example 15]

(High Frequency Welding)

A test piece 15 (i.e., an ultrathin sheet glass-acrylic resin film bonded article) of Example 15 was obtained in the same manner as in Example 1 except that the primer layer 3 surface of the silane coupling agent treated ultrathin sheet glass and the primer layer 3 surface of the silane coupling agent treated acrylic resin film were lapped on each other to form a bonding part of 10 mm × 40 mm. [0152]

(Peel Test)

The test piece 15 was subjected to the peel test in the same manner as in Example 14. The measurement results are shown in Table 6 below.

[0153]

[Comparative Example 7]

(Formation of Primer Layer)

The comparative in situ polymerization composition 3 prepared in Comparative Example 3 was coated by a spraying method to a thickness after drying of 2 μm on one surface of each of the silane coupling agent treated aluminum 1 and the silane coupling agent treated copper foil. The solvent was evaporated by allowing to stand in the air at ordinary temperature for 30 minutes, so as to form a primer layer C3.

[0154]

(High Frequency Welding)

A comparative test piece 7 (i.e., aluminum with a copper foil, which was an aluminum-copper foil bonded article) was obtained in the same manner as in Example 1 except that the primer layer C3 surface of the silane coupling agent treated aluminum 1 and the primer layer C3 surface of the silane coupling agent treated copper foil were lapped on each other to form a bonding part of 10 mm × 40 mm.

[0155] (Peel Test)

The comparative test piece 7 was subjected to the peel test in the same manner as in Example 14. The measurement results are shown in Table 6 below. [0156]

Table 6

[0157]

[Material for Test Piece]

The CFRP and the aluminum (3 cm × 50 cm) among the materials shown in Table 1 were prepared as materials for a test piece.

[0158]

<Surface Treatment (Sanding Treatmen)>

The CFRP was subjected to the sanding treatment described above.

[0159] <Surface Treatment (Boehmite Treatment)>

The aluminum was subjected to an etching treatment by immersing in a sodium hydroxide aqueous solution having a concentration of 5% by mass for 1.5 minutes, and then neutralizing with a nitric acid aqueous solution having a concentration of 5% by mass, followed by washing with water and dried. Subsequently, the aluminum having been subjected to the etching treatment was subjected to a boehmite treatment by boiling in pure water for 10 minutes and baking at 250°C for 10 minutes.

[0160]

<Functional Group Applying Treatment (Silane Coupling Agent Treatment)>

The aluminum having been subjected to the boehmite treatment and the

CFRP having been subjected to the sanding treatment each were immersed in a silane coupling agent-containing solution obtained by dissolving 2 g of 3-aminopropyltrimethoxysilane (a silane coupling agent, KBM-903, produced by Shin-Etsu Silicone Co., Ltd.) in 1,000 g of industrial ethanol at 70°C for 20 minutes. The materials were taken out from the solution and then dried to form a functional group (amino group) layer.

[0161]

<Formation of Primer Layer>

The in situ polymerization composition 1 was coated by a spraying method to a thickness after drying of 2 mm on one surface of each of the aluminum having been subjected to the silane coupling agent treatment (hereinafter referred to as silane coupling agent treated aluminum 2) and the CFRP having been subjected to the silane coupling agent treatment (hereinafter referred to as silane coupling agent treated CFRP 2). After evaporating the solvent by allowing to stand in the air at ordinary temperature for 30 minutes, the polyaddition reaction was performed by allowing to stand in a furnace at 150°C for 30 minutes, followed by cooling to ordinary temperature, so as to form a primer layer formed of a cured product of the in situ polymerization composition 1.

The surface having the primer layer formed thereon is referred to as a primer surface, and the surface having no primer layer formed thereon is referred to as a non-primer surface.

[0162]

[Example 16]

(Thermal Welding) The primer layer surface of the silane coupling agent treated aluminum 2 and the primer layer surface of the silane coupling agent treated CFRP 2 were lapped on each other, and subjected to press thermal welding at 150°C for 5 minutes.

[0163]

(Evaluation)

The bonded article thus welded was returned to ordinary temperature and allowed to stand in an ordinary temperature environment, and was observed as to whether or not warpage of the bonded article and exfoliation at the bonded surface occurred.

There was no warpage or exfoliation observed.

[0164]

[Comparative Example 8]

(Thermal Welding)

An acrylic plate was held between the non-primer surface of the silane coupling agent treated aluminum 2 and the non-primer surface of the silane coupling agent treated CFRP 2, which were subjected to press thermal welding at 180°C for 5 minutes.

[0165]

(Evaluation)

The bonded article thus welded was returned to ordinary temperature and allowed to stand in an ordinary temperature environment, and was observed as to whether or not warpage of the bonded article and exfoliation at the bonded surface occurred.

Exfoliation occurred at the bonding surface in the process of returning to ordinary temperature.

[0166]

[Example 17]

(High Frequency Welding)

The silane coupling agent treated aluminum 1 having the primer layer 3 formed on one surface thereof and the silane coupling agent treated copper foil having the primer layer 3 formed on one surface thereof were allowed to stand in a high temperature and high humidity chamber having a temperature of 85°C and a humidity of 85% for 1,000 hours. Thereafter, a test piece 17 (i.e., aluminum with a copper foil, which was an aluminum-copper foil bonded article) of Example 17 was obtained in the same manner as in Example 1 except that the primer layer 3 surface of the silane coupling agent treated aluminum 1 and the primer layer 3 surface of the silane coupling agent treated copper foil were lapped on each other to form a bonding part of 10 mm × 40 mm.

[0167]

(Peel Test)

The test piece 17 was subjected to the peel test in the same manner as in Example 14. The measurement results are shown in Table 7 below.

[0168]

[Example 18]

(High Frequency Welding)

The silane coupling agent treated ultrathin sheet glass having the primer layer 3 formed on one surface thereof and the silane coupling agent treated acrylic resin film having the primer layer 3 formed on one surface thereof were allowed to stand in a high temperature and high humidity chamber having a temperature of 85°C and a humidity of 85% for 1,000 hours. Thereafter, a test piece 18 (i.e., an ultrathin sheet glass-acrylic resin film bonded article) of Example 18 was obtained in the same manner as in Example 1 except that the primer layer 3 surface of the silane coupling agent treated ultrathin sheet glass and the primer layer 3 surface of the silane coupling agent treated acrylic resin film were lapped on each other to form a bonding part of 10 mm × 40 mm.

[0169]

(Peel Test)

The test piece 18 was subjected to the peel test in the same manner as in Example 14. The measurement results are shown in Table 7 below.

[0170]

[Comparative Example 9]

(High Frequency Welding)

The silane coupling agent treated aluminum 1 having the primer layer C3 formed on one surface thereof and the silane coupling agent treated copper foil having the primer layer C3 formed on one surface thereof were allowed to stand in a high temperature and high humidity chamber having a temperature of 85°C and a humidity of 85% for 1,000 hours. Thereafter, a comparative test piece 9 (i.e., aluminum with a copper foil, which was an aluminum-copper foil bonded article) was obtained in the same manner as in Example 1 except that the primer layer C3 surface of the silane coupling agent treated aluminum 1 and the primer layer C3 surface of the silane coupling agent treated copper foil were lapped on each other to form a bonding part of 10 mm × 40 mm.

[0171]

(Peel Test)

The comparative test piece 9 was subjected to the peel test in the same manner as in Example 14. The measurement results are shown in Table 7 below. [0172]

Table 7

Industrial Applicability [0173]

The material with a primer according to the present invention can be bonded and integrated to another material, and can be used, for example, as automobile components, such as a door side panel, an engine hood, a roof, a tailgate, a steering hanger, an A pillar, a B pillar, a C pillar, a D pillar, a crush box, a power control unit (PCU) housing, an electric compressor component (e.g., an inner wall part, an inlet port part, an exhaust control valve (ECV) insertion part, and a mount boss part), a lithium ion battery (LIB) spacer, a battery housing, and an LED head lamp, and a structural member of a smartphone, a notebook computer, a tablet computer, a smartwatch, a large size liquid crystal display television set (LCD-TV), and an outdoor LED illumination, but is not limited to these exemplified applications.

Among the bonded articles of the present invention, the bonded article of CFRP and a metal is favorable for the purpose of a multi-material component of an automobile and the like, and the bonded article of ceramics, aluminum, FRP, or the like having a copper foil bonded thereto is favorable as a board of an electronic material.

Reference Sign List [0174]

1 Material with primer

2 Material layer

21 Fine unevenness

3 Primer layer

31 In situ polymerization composition layer

32 Thermosetting resin layer

4 Functional group-containing layer

5 Bonded article

6 Bonding material

7 Material with primer

8 Material layer

9 Primer layer

10 Functional group-containing layer