Method for manufacturing joined body, joined body, and electrical / electronic component

Abstract

A method for producing a bonded body in which a columnar base material A, a thermoplastic film B, and a resin C are bonded in this order, said method comprising the following steps in this order: a step 1 in which the thermoplastic film B is wound in the circumferential direction around at least a part of the outer circumference of the columnar base material A; and a step (2) in which the thermoplastic film (B) is sealed by joining the resin (C) by insert molding to the portion of the columnar base material (A) around which the thermoplastic film (B) is wound.

Description

Technical Field

[0001] The present invention relates to a method for producing a joined body in which dissimilar materials are firmly joined, the joined body, and an electric or electronic component. Background Art

[0002] In recent years, from the perspective of lightweight and high performance of products, the use of multiple materials for parts has been gradually developed in various fields such as automotive parts, medical equipment, and home appliances. The so-called multiple materials is a method of achieving lightweight and high strength of materials by using materials with different functions and materials (hereinafter referred to as heterogeneous materials). In order to achieve multiple materials, the technology of firmly joining heterogeneous materials is indispensable.

[0003] As an example of a product that uses components that require multiple materials, a capacitor can be cited. The capacitor is constructed by having at least an insulator and an electrode body inside an outer container. In many cases, the electrode body has a positive electrode body and a negative electrode body extending from a through hole of the outer container in order to exchange electricity with the outside. In order to protect the inside of the outer container from adverse phenomena such as degeneration caused by the atmosphere, a method is adopted, for example, to use a resin material as a sealing material to seal the gap between the electrode body and the through hole. In particular, electronic equipment often produces adverse phenomena due to trace amounts of moisture, dust, etc., and a high degree of tightness (leakage resistance) is required for the sealing portion.

[0004] For example, there is a known technique of using a resin material as a sealing material to seal the periphery of a metal terminal by insert molding such as injection molding. However, for metal, if the resin material is sealed by insert molding, there is a concern that leakage may occur from the gap. In particular, when the resin material is sealed in a manner covering the periphery of a metal terminal, etc., a better leakage resistance is required.

[0005] Therefore, as a means of sealing metal terminals and the like with resin materials, for example, the following method is being studied: after applying a liquid adhesive, varnish, etc. on the metal terminal, the metal terminal is sealed with a resin material by insert molding. Specifically, the following technology is known: an in-situ polymerization type composition is applied to the electrode body and polymerized to thereby provide a primer layer, and then a sealing portion is formed (Patent Document 1, etc.). In addition, the following technology is known: an external terminal is immersed in a bath filled with a cationic epoxy resin-based electrodeposition coating, and an electric current is passed through it, thereby providing a terminal bonding layer, and then a sealing member is formed (Patent Document 2, etc.).

[0006] In addition, a method of sealing with a resin material by insert molding after roughening the surface of the metal terminal is being studied. Specifically, the following technology is known: the surface layer of the metal terminal is polished by mechanical polishing such as sandblasting, shot peening, grinding, and roller processing, or chemical polishing for the joint surface with the sealing resin (Patent Document 3, etc.).

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2021-157887

[0010] Patent Document 2: Japanese Patent Application Publication No. 2020-88137

[0011] Patent Document 3: Japanese Patent Application Publication No. 2016-126989 Summary of the invention

[0012] Problems to be solved by the invention

[0013] However, in the technology of applying liquid adhesive, sometimes it takes time to bond, which easily leads to problems such as pot life (usable time), time and labor, etc. In addition, sometimes the workability is poor due to insufficient coating amount, uneven coating work, which impairs leakage resistance, or excessive coating amount, which creates a risk of contamination.

[0014] In addition, when using a liquid thermosetting adhesive, when the metal terminal is repeatedly exposed to high and low temperatures (hot and cold cycles), the difference in the linear expansion coefficient between the metal terminal and the sealing resin causes the metal terminal and the sealing resin to be offset, exerting stress on the adhesive layer. Moreover, the adhesive layer cannot relieve the stress and peels off, which makes it easy to leak. This is because the thermosetting adhesive layer does not have thermoplasticity, and if it reaches the plastic deformation area, it will quickly break.

[0015] In addition, by roughening the surface of the electrode body, the adhesion to the sealing material will increase, but on the other hand, it is easy to produce a gap between the rough surface of the electrode body and the sealing material, and there is a concern that the leakage resistance is insufficient. In addition, since there is no layer to relax stress during the above-mentioned hot and cold cycles, it is easy to peel off.

[0016] In order to further ensure airtightness, not only is it required that the base material and the sealing material adhere more firmly, but also that stress relaxation during thermal cycling is required.

[0017] Therefore, an object of the present invention is to provide a method for producing a joined body, a joined body, and an electric or electronic component in which the joining process time is short, dissimilar materials are firmly joined, and the joined body has excellent leakage resistance.

[0018] Means for solving problems

[0019] The inventors of the present application have found that the above-mentioned problems can be solved by winding a predetermined film on a substrate, bonding the wound film to the substrate, and then sealing the wound film with a resin.

[0020] That is, the present invention is as follows.

[0021] [1] A method for producing a bonded body, wherein the bonded body is produced by sequentially bonding a columnar substrate A, a thermoplastic film B, and a resin C, the method comprising the following steps in sequence:

[0022] Step 1, winding the thermoplastic film B along the circumferential direction around at least a portion of the outer periphery of the columnar substrate A; and

[0023] In step 2, the resin C is bonded to the portion of the columnar substrate A around which the thermoplastic film B is wound by insert molding, thereby sealing the thermoplastic film B.

[0024] [2] The method for producing a joined body according to [1] above, wherein the thermoplastic film B has adhesiveness to the columnar substrate A.

[0025] [3] The method for producing a joined body according to [1] or [2], wherein in the step 1, the following operation is further performed: the rolled thermoplastic film B is melted and solidified to join the columnar substrate A and the thermoplastic film B.

[0026] [4] According to the method for manufacturing a joined body described in [3] above, in the above step 1, the joining of the above columnar substrate A and the above thermoplastic film B is carried out by at least one method selected from contact heating, hot air heating, hot pressing, infrared heating, hot plate welding, ultrasonic welding, vibration welding and high-frequency induction welding.

[0027] [5] The method for producing a bonded body according to [3] or [4], wherein in the step 1, the columnar substrate A and the thermoplastic film B are bonded at a heating temperature of 100 to 300°C.

[0028] [6] The method for producing a joined body according to any one of [1] to [5] above, wherein the width of the thermoplastic film B in a direction perpendicular to the circumferential direction is 3 to 30 mm.

[0029] [7] The method for producing a joined body according to any one of [1] to [6], wherein the thermoplastic film B has a thickness of 10 μm or more and 3 mm or less.

[0030] [8] According to the method for producing a joined body described in any one of [1] to [7] above, if the melting point of the thermoplastic film B is X°C, or if the melting point does not exist, the temperature obtained by adding 70°C to the glass transition temperature is X°C, and the resin temperature of the resin C during molding is Y°C, then the value obtained by subtracting X°C from Y°C is 100 to 250°C.

[0031] [9] The method for producing a joined body according to any one of [1] to [8], wherein the thermoplastic film B contains an amorphous thermoplastic resin as a main component.

[0032]

[10] The method for producing a bonded body according to [9] above, wherein the amorphous thermoplastic resin is at least one resin selected from thermoplastic epoxy resins and phenoxy resins.

[0033]

[11] The method for producing a joined body according to any one of [1] to

[10] , wherein the thermoplastic film B is a thermoplastic resin having an epoxy equivalent of 1,600 g / eq. or more or a thermoplastic resin containing no epoxy group.

[0034]

[12] The method for producing a bonded body according to any one of [1] to

[11] above, wherein the columnar substrate A is a metal.

[0035]

[13] The method for producing a joined body according to any one of [1] to

[12] above, wherein the resin C is a thermoplastic resin.

[0036]

[14] A bonded body obtained by the method for manufacturing a bonded body according to any one of [1] to

[13] above, wherein when an air pressure of 0.1 MPaG is applied to the sealing portion to perform a leakage test, the air leakage amount is 1 ml / min or less.

[0037]

[15] The bonded body according to

[14] , wherein the bonded body is heated to a temperature not less than the glass transition temperature of the thermoplastic film B and not more than 160°C, maintained at the temperature for 1000 minutes, cooled to 23°C, and then subjected to the leakage test, and the air leakage amount is not more than 1 ml / min.

[0038]

[16] An electric or electronic component comprising a joined body obtained by the method for producing a joined body according to any one of [1] to

[13] above, and a joined body according to

[14] or

[15] above.

[0039]

[17] The electric or electronic component according to

[16] above, which is a terminal block or an electric element.

[0040] Effects of the Invention

[0041] According to the present invention, a method for producing a bonded body in which the bonding process time is short, dissimilar materials are firmly bonded, and the bonded body and electric and electronic components are excellent in leakage resistance can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] [ Figure 1 ] is a front view showing an example of an implementation of a substrate with a film.

[0043] [ Figure 2 ] is adopted by Figure 1 An explanatory diagram of step 1 for forming a cross section taken along a BB' cross section parallel to the Y axis of the substrate with a film.

[0044] [ Figure 3 ] is an explanatory diagram of step 2 using the cross-section of the substrate with film and the mold obtained in step 1.

[0045] [ Figure 4 ] is a cross-sectional view formed by a section parallel to the width direction of the joint body.

[0046] [ Figure 5 ] is a cross-sectional view formed by a section parallel to the length direction of the joint body.

[0047] [ Figure 6 ] is a schematic diagram of a joint body used to illustrate an embodiment. DETAILED DESCRIPTION

[0048] Hereinafter, embodiments of the present invention will be described in detail.

[0049] In this specification, the term "joining" refers to connecting articles to each other, and bonding and welding are subordinate concepts. The term "bonding" refers to the bonding of two bonded materials (materials to be bonded) by means of organic materials such as tapes and adhesives (thermosetting resins, thermoplastic resins, etc.). The term "welding" refers to the bonding of two bonded materials (materials to be bonded) by means of heat-melting the surface of thermoplastic resins, etc., followed by cooling, thereby generating entanglement caused by molecular diffusion and forming a bonded state. The term "adhesiveness" refers to the property of having bonding strength that enables articles to be connected to each other.

[0050] In this specification, the term "a bonded body formed by bonding in this order" means bonding in this order in space.

[0051] In this specification, the term "joining process time" refers to the time from the moment when the substrate and the film constituting the joined body come into contact as the starting point to the moment when the production of the joined body is completed as the end point, including, for example, the time required for winding the film around the substrate and for joining and sealing the resin by insert molding.

[0052] <Method for producing a bonded body>

[0053] The method for producing a bonded body of the present embodiment is a method for producing a bonded body produced by sequentially bonding a columnar substrate A, a thermoplastic film B, and a resin C. The method sequentially comprises the following steps:

[0054] Step 1, winding a thermoplastic film B along a circumferential direction around at least a portion of the outer periphery of a columnar substrate A; and

[0055] In step 2, the thermoplastic film B is sealed by bonding the resin C to the portion of the columnar substrate A around which the thermoplastic film B is wound by insert molding.

[0056] By providing the thermoplastic film B between the columnar substrate A and the resin C as the sealing material, the columnar substrate A and the resin C are firmly bonded. In addition, since the thermoplastic film B can be wound around the columnar substrate A, it can be said that it is an effective operation to shorten the bonding process compared to applying a liquid adhesive or the like. In addition, by using the thermoplastic film B having a uniform thickness, compared to the case of applying a liquid adhesive or the like, uneven portions such as coating residues and sagging are not generated, and excellent leakage resistance can be exhibited.

[0057] The reasons why the effects of the present invention can be obtained in more detail are discussed as follows.

[0058] By providing a thermoplastic resin that has completed a chemical reaction such as polymerization between the columnar substrate A and the resin C, rapid solidification can be achieved by utilizing the phase change between solid and liquid, and the bonding process can be shortened. In addition, by using the thermoplastic resin in a film form, there is no tediousness in handling the liquid compared to applying an amorphous liquid bonding agent, and the bonding process time is shortened.

[0059] In addition, if it is a thermoplastic resin, it also has thermoplasticity at high temperature, so it can relax stress, and can reset stress in each cycle during hot and cold cycles, and can prevent peeling. Therefore, by using the thermoplastic film B, plastic deformation can be performed, and stress can be effectively relaxed, so that it can be made into a joint body that is not easy to peel off during hot and cold cycles and has excellent leakage resistance. In addition, when the joint body is exposed to high temperature, the resin C softens, thereby, it can more effectively relax stress, so it has excellent leakage resistance.

[0060] Furthermore, as an example of a preferred embodiment, when an amorphous thermoplastic film B is used as the thermoplastic film B, the film is less likely to rapidly decrease in viscosity when heated, and thus can maintain a shape for maintaining leakage resistance when the bonded body is exposed to high temperatures.

[0061] [Process 1]

[0062] In step 1, the thermoplastic film B is wound around at least a portion of the outer periphery of the columnar substrate A in the circumferential direction.

[0063] Here, the “at least a portion of the periphery” refers to at least a portion in the long axis direction of the columnar substrate A. The “winding” refers to winding the thermoplastic film B along the circumferential direction of the columnar substrate A once or more.

[0064] use Figure 1 and Figure 2 An example of an implementation of step 1 will be described.

[0065] Figure 1 It is a front view which shows an example of embodiment of the substrate with a film. Figure 2 For the adoption of Figure 1 An explanatory diagram of step 1 for forming a cross section taken along a BB' cross section parallel to the Y axis of the substrate with a film.

[0066] like Figure 1 and Figure 2 As shown in FIG. 1 , the thermoplastic film B30 may be wound around at least a portion of the periphery of the columnar substrate A20. Figure 1 As shown, the unbonded portion a of the thermoplastic film B30 is provided at a part of the columnar substrate A20, but it may not have the unbonded portion a, or it may have the unbonded portion a only at one end of the columnar substrate A20. The columnar substrate A20 preferably has the unbonded portion a at both ends.

[0067] In step 1, first, Figure 2 As shown in FIG. 2-1, the thermoplastic film B30 is wound along the circumferential direction around the outer periphery of the columnar substrate A20. Figure 2 As shown in FIG2-2, the thermoplastic film B30 may be wound so as to continuously cover the outer circumference of the columnar substrate A20. Since the thermoplastic film B30 is wound one or more times along the circumferential direction of the columnar substrate A20, there is no gap at both end edges of the wound thermoplastic film B30, the airtightness is improved, and excellent leakage resistance can be exhibited.

[0068] The thermoplastic film B may have adhesiveness. It is preferred that the thermoplastic film B has adhesiveness and is temporarily fixed to the columnar substrate A from the viewpoint of ease of handling.

[0069] Alternatively, the thermoplastic film B may be coated with an adhesive within a range that does not impair the leakage resistance, and then wound around the columnar substrate A to be temporarily fixed. As the adhesive, a commercially available product may be used.

[0070] After the thermoplastic film B is wound around the outer circumference of the columnar substrate A as described above, it is preferred that the columnar substrate A and the thermoplastic film B be bonded by melting and solidifying the wound thermoplastic film B.

[0071] Specifically, if Figure 2 As shown in FIG. 2-2, after the thermoplastic film B30 is wound on the columnar substrate A20, the thermoplastic film B30 can be melted and solidified. The thermoplastic film B30 is thermoplastic, so Figure 2 As shown in 2-3, it is tightly bonded to the columnar substrate A20 without any gap.

[0072] In this embodiment, the resin C is insert-molded in the following step 2, thereby melting and solidifying the thermoplastic film B. Therefore, the thermoplastic film B may be melted and solidified in step 1 by heating in the molding step of the resin C in step 2. On the other hand, by melting and solidifying the thermoplastic film B in advance, the columnar substrate A and the thermoplastic film B can be more reliably bonded and integrated, thereby improving the sealing performance and making the leakage resistance more excellent.

[0073] 〔Melting and solidification〕

[0074] As a method for melting the thermoplastic film B during the bonding of the columnar substrate A and the thermoplastic film B, there can be mentioned at least one method selected from contact heating, hot air heating, hot pressing, hot plate welding, infrared heating, ultrasonic welding, vibration welding and high-frequency induction welding.

[0075] Among them, hot pressing or high-frequency induction welding is preferred from the viewpoint of ease of production and shortening of the joining process.

[0076] When the thermoplastic film B is melted by heating during the bonding of the columnar substrate A and the thermoplastic film B, the heating temperature of the bonding surface between the columnar substrate A and the thermoplastic film B may be determined in consideration of the heat resistance temperature of the material of the columnar substrate A, but is preferably 100 to 300° C., more preferably 120 to 250° C., and even more preferably 150 to 220° C. By heating at 100 to 300° C., the thermoplastic film B is efficiently deformed, melted, and effectively wetted and spread on the bonding surface, so that a high bonding strength can be obtained.

[0077] As a method for solidifying the melted thermoplastic film B, there can be mentioned a method of cooling at room temperature or a method of cooling using a cooling device. It should be noted that the so-called "room temperature" refers to a normal room temperature in the range of 5 to 30° C. Among them, the method of cooling at room temperature is preferred from the viewpoint of ease of production.

[0078] It should be noted that, in this specification, the term "solidified" means being solid at room temperature, that is, having no fluidity in a non-pressurized state at 23°C.

[0079] 〔Columnar substrate A〕

[0080] The shape of the columnar substrate A is not particularly limited. The cross section perpendicular to the length direction of the columnar substrate A can be, for example, a circular shape, a semicircular shape, an elliptical shape, a square shape, a rectangular shape, a triangle shape, and other polygonal shapes. The polygon may be a regular polygon or a shape other than a regular polygon. In addition, a rectangular prism (strip) having a large aspect ratio in cross section is also included in the columnar substrate A.

[0081] Examples of the material of the columnar substrate A include metals and inorganic substances. The material of the columnar substrate A may be used alone or in combination of two or more.

[0082] From the viewpoint of heat resistance and strength, the columnar substrate A is preferably a metal. When the material of the columnar substrate A is a resin, the material of the resin must have a melting point or a glass transition temperature at which it does not deform at the temperature during insert molding in step 2.

[0083] The metal is not particularly limited, and examples thereof include aluminum, iron, copper, magnesium, and titanium.

[0084] It should be noted that, in the present embodiment, the term "iron" is used to include iron and its alloys. As iron alloys, for example, steel, stainless steel, etc. can be cited. Similarly, copper, aluminum, magnesium, and titanium are also used to include their simple substances and their alloys.

[0085] The inorganic material is not particularly limited, and examples thereof include glass, ceramics, and carbon molded bodies.

[0086] As glass, for example, in addition to ordinary glass, it may be heat-resistant glass, fire-resistant glass, fire-resistant glass, chemically strengthened glass used for protection of smartphones, etc. Specifically, soda-lime glass, lead glass, borosilicate glass, quartz glass, etc. may be mentioned.

[0087] Examples of ceramics include fine ceramics used in semiconductors, automobiles, industrial equipment, etc. Specifically, examples include oxide ceramics such as alumina, zirconium oxide, and barium titanate; hydroxide ceramics such as hydroxyapatite, carbide ceramics such as silicon carbide; and nitride ceramics such as silicon nitride.

[0088] Examples of the resin used as the material of the columnar substrate A include glass fiber reinforced thermosetting resins, cured products of thermosetting resins such as epoxy resins, vinyl ester resins, and unsaturated polyesters, and highly heat-resistant engineering plastics such as polyimide resins, polyetherimide, and polyethersulfone.

[0089] (Pre-processing)

[0090] The columnar substrate A is preferably subjected to a surface pretreatment for the purpose of removing contaminants on the surface and / or achieving an anchoring effect.

[0091] Examples of the pretreatment include degreasing treatment, UV ozone treatment, sandblasting treatment, polishing treatment, plasma treatment, corona discharge treatment, laser treatment, etching treatment, and flame treatment.

[0092] As a pretreatment, it is preferred to wash the surface of the columnar substrate A or to give the surface a concavoconvex pretreatment. Specifically, when the columnar substrate A is made of aluminum, copper, glass, ceramics or iron, it is preferably selected from at least one treatment of degreasing treatment, UV ozone treatment, sandblasting, grinding treatment, plasma treatment, and etching treatment. When the columnar substrate A is made of FRP, polypropylene, polycarbonate, polymethyl methacrylate, polyetherimide, polyamide or polybutylene terephthalate, it is preferably selected from at least one treatment of degreasing treatment, UV ozone treatment, sandblasting, grinding treatment, plasma treatment and corona discharge treatment.

[0093] Only one type of pretreatment may be performed, or two or more types may be performed. As specific methods of these pretreatments, known methods can be adopted.

[0094] The degreasing treatment is a method of dissolving and removing dirt such as grease on the surface of the columnar substrate A using an organic solvent such as acetone or toluene.

[0095] UV ozone treatment is a method of cleaning or modifying a surface by using the energy of short-wavelength ultraviolet rays emitted from a low-pressure mercury lamp and the effect of ozone (O3) generated thereby. In the case of glass, it is one of the surface cleaning methods for removing organic impurities on the surface. Usually, a cleaning surface modification device using a low-pressure mercury lamp is called a "UV ozone cleaner", "UV cleaning device", "ultraviolet surface modification device", etc.

[0096] Examples of the blasting process include wet blasting, shot blasting, sand blasting, etc. Among them, wet blasting is preferred because it can obtain a denser surface than dry blasting.

[0097] Examples of the polishing treatment include polishing using a polishing cloth, roll polishing using a polishing paper (sandpaper), and electrolytic polishing.

[0098] Plasma treatment is a treatment that uses a high voltage power supply and a rod to produce a plasma beam and irradiate it onto the surface of a material to excite molecules and make them functional. Examples of such treatments include atmospheric pressure plasma treatments that can impart hydroxyl groups or polar groups to the surface of a material.

[0099] The corona discharge treatment is a method for modifying the surface of a polymer film, in which electrons released from an electrode cut the main chain and side chain of the polymer surface layer to generate free radicals, thereby generating hydroxyl groups and polar groups on the surface.

[0100] Laser processing is a technique for improving the properties of the surface by rapidly heating and cooling only the surface of the columnar substrate A by laser irradiation, and is an effective method for roughening the surface. A known laser processing technique can be used.

[0101] Examples of the etching treatment include chemical etching treatments 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 electrochemical etching treatments such as an electrolytic etching method.

[0102] The flame treatment is a method of converting oxygen in the air into plasma by burning a mixed gas of combustion gas and air, and applying oxygen plasma to the object to be treated to achieve surface hydrophilization. A known flame treatment technique can be used.

[0103] [Thermoplastic film B]

[0104] The thermoplastic film B contains a thermoplastic resin as a main component. In addition, the thermoplastic film B preferably has adhesiveness to the columnar substrate A.

[0105] The above-mentioned "main component" refers to the component with the highest content among the resin components in the thermoplastic film B. The thermoplastic film B preferably contains 50% by mass or more of the resin component, more preferably 70% by mass or more of the resin component, further preferably 80% by mass or more of the resin component, and particularly preferably 90% by mass or more of the resin component.

[0106] The above-mentioned "film" refers to a film obtained by molding a resin composition containing a thermoplastic resin as a main component into a thin film.

[0107] 《Y℃-X℃》

[0108] When the thermoplastic resin used for the thermoplastic film B has a melting point, the melting point of the thermoplastic film B is represented by X°C. Alternatively, when the thermoplastic resin used for the thermoplastic film B does not have a melting point, the temperature obtained by adding 70°C to the glass transition temperature is represented by X°C, and the resin temperature during molding of the resin C is represented by Y°C. The value obtained by subtracting X°C from Y°C (Y°C-X°C) is preferably 0 to 300°C, more preferably 50 to 250°C, further preferably 100 to 250°C, and further preferably 125 to 210°C.

[0109] By setting the Y°C - X°C within the range of 0 to 300°C, the thermoplastic film B is efficiently melted by the heating of the resin C during molding and effectively wets and spreads on the bonding surface, thereby achieving high adhesion and excellent leakage resistance.

[0110] In this specification, the melting point of a thermoplastic resin refers to the melting peak temperature measured by DSC. It should be noted that when no melting peak is obtained and the heat of fusion is 15 J / g or less, the temperature obtained by adding 70°C to the glass transition temperature is regarded as the melting point. The glass transition temperature refers to the temperature at which the DSC curve of the second cycle of heating to 200°C, cooling to below 40°C, and further heating to 200°C begins to decrease. Specifically, it is a value measured by the method described in the Examples.

[0111] 《Amorphous Thermoplastic Resins》

[0112] The thermoplastic film B preferably contains an amorphous thermoplastic resin as a main component.

[0113] The amorphous thermoplastic resin refers to a resin that has no crystals, or even if it has crystals, the crystals are small and the heat of fusion is 15 J / g or less.

[0114] The heat of fusion is calculated from the area of ​​the endothermic peak of DSC (differential scanning calorimeter) and the weight of the thermoplastic resin component. In the case where the film contains an inorganic filler, etc., it is calculated from the weight of the thermoplastic resin component excluding the inorganic filler. Specifically, 2 to 10 mg of a sample can be weighed, placed in an aluminum pan, and heated from 23°C to 200°C or above using DSC (DSC8231 manufactured by Rigaku Co., Ltd.) at 10°C / min to obtain a DSC curve, and then, the heat of fusion is calculated based on the area of ​​the endothermic peak during melting obtained from the DSC curve and the above-mentioned weighed value.

[0115] The heat of fusion of the amorphous thermoplastic resin is more preferably 11 J / g or less, further preferably 7 J / g or less, and still further preferably 4 J / g or less, and it is particularly preferred that the melting peak is below the detection limit.

[0116] By using a thermoplastic film B having an amorphous thermoplastic resin having a melting heat of 15 J / g or less as a main component, the viscosity does not drop sharply when heated as in conventional hot melt adhesives, and the film does not become a low viscosity (0.001 to 100 Pa·s) state in a high temperature range exceeding 200° C. Therefore, the thermoplastic film B does not flow out from between the columnar substrate A and the resin C even in a molten state, and the thickness of the thermoplastic film B can be stably ensured, and a high bonding strength can be stably obtained.

[0117] From the perspective of sufficiently imparting the properties of the amorphous thermoplastic resin to the thermoplastic film B, the content of the amorphous thermoplastic resin in the resin component in the thermoplastic film B is preferably 60% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, and most preferably 90% by mass or more.

[0118] In addition, from the viewpoint of sealing properties and toughness, the amorphous thermoplastic resin is preferably at least one resin selected from thermoplastic epoxy resins and phenoxy resins.

[0119] Among them, from the viewpoint of airtightness and toughness, the thermoplastic film B is more preferably mainly composed of an amorphous thermoplastic resin which is at least one of a thermoplastic epoxy resin and a phenoxy resin. In addition, from the viewpoint of airtightness and toughness, the thermoplastic film B is further preferably mainly composed of an amorphous thermoplastic resin which is at least one of a thermoplastic epoxy resin and a phenoxy resin and has an epoxy equivalent of 1,600 or more and a heat of fusion of 15 J / g or less.

[0120] The above-mentioned "main component" refers to the component with the highest content among the resin components in the thermoplastic film B. The thermoplastic film B preferably contains 50% by mass or more of the resin component, more preferably 70% by mass or more of the resin component, further preferably 80% by mass or more of the resin component, and particularly preferably 90% by mass or more of the resin component.

[0121] Thermoplastic epoxy resins and phenoxy resins have low cohesive strength within the resin and may have hydroxyl groups, so they interact strongly with the columnar substrate A and the resin C, and can be expected to bond dissimilar materials with a higher bonding strength than conventional crystalline hot melt adhesives.

[0122] Among them, from the viewpoint of storage properties, the thermoplastic film B is preferably a thermoplastic resin having an epoxy equivalent of 1,600 g / eq. or more or a thermoplastic resin containing no epoxy group.

[0123] The epoxy equivalent is more preferably 2,000 g / eq. or more, further preferably 5,000 g / eq. or more, and further preferably 9,000 g / eq. or more, and particularly preferably above the detection limit and substantially no epoxy group is detected. It should be noted that the epoxy equivalent being above the detection limit means that no epoxy group is detected when the epoxy equivalent is measured based on JIS K 7236:2001 described below.

[0124] The epoxy equivalent (the weight of the above-mentioned thermoplastic resin containing 1 mol of epoxy groups) referred to herein is the value of the epoxy equivalent of the thermoplastic resin contained in the thermoplastic film B before bonding, and is a value measured by the method specified in JIS-K7236:2001 (unit: "g / eq."). Specifically, it is the following value: using a potentiometric titration apparatus, adding an acetic acid solution of tetraethylammonium bromide, using a 0.1 mol / L perchloric acid-acetic acid solution, and calculating the value as a solid content conversion value from the non-volatile component for a solvent-diluted product (resin varnish). It should be noted that in the case of a mixture of two or more resins, it can also be calculated from the respective contents and epoxy equivalents.

[0125] 《Thermoplastic Epoxy Resin》

[0126] The thermoplastic epoxy resin is preferably a polymer of (a) a bifunctional epoxy resin monomer or oligomer and (b) a bifunctional compound having two identical or different functional groups selected from phenolic hydroxyl groups, carboxyl groups, mercapto groups, isocyanate groups and cyanate groups.

[0127] By using the above-mentioned compound, the polymerization reaction to form a linear polymer proceeds preferentially, and a thermoplastic epoxy resin having desired properties can be obtained.

[0128] (a) The bifunctional epoxy resin monomer or oligomer refers to an epoxy resin monomer or oligomer having two epoxy groups in the molecule.

[0129] Specific examples of the (a) bifunctional epoxy resin monomer or oligomer include, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bifunctional phenol novolac type epoxy resin, bisphenol AD ​​type epoxy resin, biphenyl type epoxy resin, bifunctional naphthalene type epoxy resin, bifunctional alicyclic epoxy resin, bifunctional glycidyl ester type epoxy resin (e.g., diglycidyl phthalate, diglycidyl tetrahydrophthalate, diglycidyl dimer acid diglycidyl ester, etc.), bifunctional glycidyl amine type epoxy resin (e.g., diglycidyl aniline, diglycidyl toluidine, etc.), bifunctional heterocyclic epoxy resin, bifunctional diaryl sulfone type epoxy resin, hydroquinone type epoxy resin (e.g., hydroquinone diglycidyl ether, 2,5-dihydro-1-nitro-1-ol, di-1-nitro-1-nitro-1-ol, di-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro-1-nitro- -di-tert-butylhydroquinone diglycidyl ether, resorcinol diglycidyl ether, etc.), bifunctional alkylene glycidyl ether compounds (for example, butanediol diglycidyl ether, butenediol diglycidyl ether, butynediol diglycidyl ether, etc.), bifunctional glycidyl group-containing hydantoin compounds (for example, 1,3-diglycidyl-5,5-dialkylhydantoin, 1-glycidyl-3-(glycidyloxyalkyl)-5,5-dialkylhydantoin, etc.), bifunctional glycidyl group-containing siloxanes (for example, 1,3-bis(3-glycidyloxypropyl)-1,1,3,3-tetramethyldisiloxane, α,β-bis(3-glycidyloxypropyl)polydimethylsiloxane, etc.), and modified products thereof. Among them, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and biphenyl type epoxy resin are preferred from the viewpoint of reactivity and workability.

[0130] Examples of the bifunctional compound having a phenolic hydroxyl group (b) include mononuclear aromatic dihydroxy compounds having one benzene ring such as catechol, resorcinol, and hydroquinone, bisphenols such as bis(4-hydroxyphenyl)propane (bisphenol A), bis(4-hydroxyphenyl)methane (bisphenol F), and bis(4-hydroxyphenyl)ethane (bisphenol AD), compounds having a condensed ring such as dihydroxynaphthalene, bifunctional phenol compounds into which an allyl group is introduced such as diallylresorcinol, diallylbisphenol A, and triallyldihydroxybiphenyl, and dibutylbisphenol A.

[0131] Specific examples of the carboxyl group-containing compound (b) include adipic acid, succinic acid, malonic acid, cyclohexanedicarboxylic acid, phthalic acid, isophthalic acid, and terephthalic acid.

[0132] Examples of the bifunctional compound having a mercapto group (b) include ethylene glycol bismercaptoacetate and ethylene glycol bismercaptopropionate.

[0133] Specific examples of the isocyanate group-containing bifunctional compound (b) include diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HMDI), and toluene diisocyanate (TDI).

[0134] Specific examples of the bifunctional compound containing a cyanate group (b) include 2,2-bis(4-cyanophenyl)propane, 1,1-bis(4-cyanophenyl)ethane, and bis(4-cyanophenyl)methane.

[0135] Among the bifunctional compounds of the above (b), bifunctional compounds having a phenolic hydroxyl group are preferred from the viewpoint of obtaining a thermoplastic polymer, bifunctional compounds having two phenolic hydroxyl groups and a bisphenol structure or a biphenyl structure are preferred from the viewpoint of heat resistance and bonding properties, and at least one compound selected from bisphenol A, bisphenol F and bisphenol S is preferred from the viewpoint of heat resistance and cost.

[0136] When (a) is a bisphenol A epoxy resin, a bisphenol F epoxy resin, a bisphenol S epoxy resin, or a biphenyl epoxy resin, and (b) is bisphenol A, bisphenol F, or bisphenol S, the polymer obtained by polymerization of (a) and (b) has a main chain having a paraphenylene structure and an ether bond as the main skeleton and connecting them with an alkylene group, and a structure in which hydroxyl groups generated by addition polymerization are arranged on the side chains.

[0137] The mechanical strength of the polymer after polymerization can be improved by the linear structure composed of the paraphenylene skeleton, and the adhesion to the substrate can be improved by the hydroxyl group arranged on the side chain. As a result, the workability of the thermosetting resin can be maintained and high bonding strength can be achieved. In addition, in the case of a thermoplastic resin, it can be softened / melted by heat, so that it can be recycled and repaired, which can improve the recyclability and repairability that are problematic points in thermosetting resins.

[0138] 《Phenoxy resin》

[0139] Phenoxy resin is a polyhydroxy polyether synthesized from bisphenols and epichlorohydrin, and has thermoplasticity. In order to manufacture phenoxy resin, it is known that there are methods using the direct reaction of dihydric phenols and epichlorohydrin, and methods using the addition polymerization reaction of diglycidyl ether of dihydric phenols and dihydric phenols. The phenoxy resin used in this embodiment can be a phenoxy resin obtained by any preparation method. In the case of the direct reaction of dihydric phenols and epichlorohydrin, as dihydric phenols, for example, phenols such as bisphenol A, bisphenol F, bisphenol S, biphenol, biphenylene diol, and diphenylfluorene can be cited; aliphatic diols such as ethylene glycol, propylene glycol, and diethylene glycol. Among them, from the viewpoint of cost, bonding, viscosity, and heat resistance, bisphenol A, bisphenol F, and bisphenol S are preferred. They can be used alone or in combination of two or more.

[0140] Phenoxy resin has a chemical structure similar to that of epoxy resin, and has a main chain having a p-phenylene structure and an ether bond as a main skeleton and connecting them, and a structure in which hydroxyl groups are arranged on side chains.

[0141] 《Physical Properties of Thermoplastic Epoxy Resins and Phenoxy Resins》

[0142] The weight average molecular weight of the thermoplastic epoxy resin and the phenoxy resin is preferably 10,000 to 500,000, more preferably 18,000 to 300,000, and further preferably 20,000 to 200,000, and the weight average molecular weight is a value obtained by GPC (gel permeation chromatography) measured in terms of polystyrene conversion. The weight average molecular weight is the value of the molecular weight obtained by calculating the elution peak position detected by GPC and converting it to standard polystyrene. If the weight average molecular weight is within the range of this value, the balance between thermoplasticity and heat resistance is good, and a bonded body can be obtained efficiently by melting, and its heat resistance also becomes high. If the weight average molecular weight is 10,000 or more, the heat resistance is excellent, and if the weight average molecular weight is 500,000 or less, the viscosity during melting is low and the bonding property becomes high.

[0143] <<Components other than resin component in thermoplastic film B>>

[0144] The thermoplastic film B may contain fillers and additives as components other than the resin component as necessary within a range not hindering the purpose of the present embodiment.

[0145] Examples of the filler include inorganic fillers and organic fillers (resin powders and the like).

[0146] Examples of the inorganic filler include spherical fused silica, metal powders such as iron, silica sand, talc, calcium carbonate, mica, acid clay, diatomaceous earth, kaolin, quartz, titanium oxide, silicon dioxide, phenolic resin microspheres, and glass spheres.

[0147] When the thermoplastic film B contains a filler, the content of the filler in 100% by volume of the total amount of the thermoplastic film B is preferably 50% by volume or less, more preferably 30% by volume or less, further preferably 20% by volume or less, and most preferably 10% by volume or less. It should be noted that the volume of the filler can be obtained by dividing the weight of the filler contained in the thermoplastic film B by the apparent specific gravity of the filler.

[0148] The content of the resin component in 100% by volume of the total amount of the thermoplastic film B is preferably 10% by volume or more, more preferably 20% by volume or more, further preferably 30% by volume or more, further preferably 50% by volume or more, in one embodiment, 80% by volume or more, in another embodiment, 90% by volume or more, and in another embodiment, 99% by volume or more.

[0149] Examples of the additives include defoaming agents, coupling agents such as silane coupling agents, pigments, and tackifier resins. These additives may be contained alone or in combination of two or more.

[0150] The content of the additive in the thermoplastic film B is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 1% by mass or less.

[0151] The content of the resin component in the thermoplastic film B is preferably 10% by mass or more, more preferably 20% by mass or more, further preferably 30% by mass or more, further preferably 50% by mass or more, in one embodiment, 80% by mass or more, in another embodiment, 90% by mass or more, and in another embodiment, 99% by mass or more.

[0152] 《Morphology of thermoplastic film B》

[0153] The thermoplastic film B is in the form of a sheet.

[0154] The width of the thermoplastic film B in the direction perpendicular to the circumferential direction of the columnar substrate A is preferably 3 to 30 mm. Figure 1 The b in it represents.

[0155] From the viewpoint of obtaining a firmly bonded bonded body with a short bonding process time, the width of the thermoplastic film B is more preferably 25 mm or less, and further preferably 20 mm or less. In addition, from the same viewpoint, the width of the thermoplastic film B is more preferably 4 mm or more, and further preferably 5 mm or more.

[0156] The thickness of the thermoplastic film B is preferably 10 μm or more and 3 mm or less. Figure 2 The c in it represents.

[0157] From the viewpoint of obtaining a firmly bonded body in a short bonding process time, the thickness of the thermoplastic film B is more preferably 1 mm or less, further preferably 0.5 mm or less, further preferably 0.3 mm or less, particularly preferably 0.2 mm or less, and most preferably 0.1 mm or less. In addition, from the viewpoint of further improving the adhesion and leakage resistance, the thickness of the thermoplastic film B is more preferably 20 μm or more, further preferably 30 μm or more, and particularly preferably 40 μm or more.

[0158] When the thickness of the thermoplastic film B is within the above numerical range, the film can be efficiently spread on the bonding surface with the columnar substrate A by heating or the like, and high bonding strength and leakage resistance can be obtained.

[0159] The thermoplastic film B may be a single layer or a laminate composed of a plurality of layers. However, from the viewpoint of ease of production and improvement of bonding strength, the thermoplastic film B is preferably a single layer.

[0160] In addition, in the scope that does not hinder the leakage resistance, thermoplastic film B also can have viscosity as mentioned above.The giving of viscosity can be to mix tackifying resin in the thermoplastic resin constituting thermoplastic film B, or it can be that adhesive is coated on the surface of thermoplastic film B.The giving of viscosity can be one side, or it can be two sides, but if it is one side, then can only have viscosity in the face contacted with columnar substrate A, be difficult to expose adhesive surface in the outside, therefore be more preferred.In addition, the coating area of ​​adhesive can be the whole face, or it can be the coating of a part such as stripe, dot, lattice, tile (a plurality of squares are arranged in a mode with a gap).If the coating area is few, then adhesive is difficult to overflow from the end face of thermoplastic film B to the outside and expose, and leakage resistance is difficult to decline, thereby is preferred.In addition, the giving of viscosity can be the tiny viscosity that can only be antiskid. That is, when the thermoplastic film B is wound around the columnar substrate A, the thermoplastic film B may not adhere to the columnar substrate A, but may have a resistance that increases (becomes less likely to slide) when a shearing force is applied. The lower the viscosity, the easier it is to increase the adhesive force, and the better the leakage resistance, which is preferred.

[0161] 《Method for producing thermoplastic film B》

[0162] The method for producing the thermoplastic film B is not particularly limited. For example, a monomer or oligomer of a bifunctional epoxy compound may be heated to polymerize to obtain a resin composition, a solvent may be added to the obtained resin composition as required, the composition may be applied to a release film, etc., cured and dried, and pressed as required to obtain the thermoplastic film B. The polymerization reaction may be carried out after applying to a release film or after removing the solvent to obtain a film shape, or a combination of these methods may be used.

[0163] [Process 2]

[0164] In step 2, the resin C is bonded to the wound portion of the thermoplastic film B bonded to the columnar substrate A by insert molding, thereby sealing the wound portion.

[0165] 〔Insert molding〕

[0166] The insert molding can be performed by a conventionally known method.

[0167] use Figure 3 and Figure 4 An example of implementation of step 2 will be described. Figure 3 This is an explanatory diagram of step 2 using the cross section of the substrate with a film obtained in step 1 and the mold. Figure 4 It is a cross-sectional view formed by a section parallel to the width direction of the bonded body.

[0168] like Figure 3 As shown, a film-attached substrate 1 obtained by winding a thermoplastic film B30 around a columnar substrate A20 obtained in step 1 is set in the cavity of the insert molding die 50 and filled with a molten resin C40a by heating and pressurizing.

[0169] Specifically, after the substrate 1 with a film is set in the cavity of the insert molding die 50 ( Figure 3 ), and a filling resin C40a is injected into the cavity from a resin injection port provided in the mold. At this time, insert molding is performed in such a manner that the thermoplastic film B30 with a film is covered with at least a portion, preferably the entirety, of the substrate 1 and the resin C is bonded, and the substrate is taken out from the mold 50. By passing through step 2, as shown in FIG. Figure 4 As shown, a bonded body 10 is produced in which the columnar base material A20 is sealed by the resin C40 via the thermoplastic film B30.

[0170] The mold for insert molding is not particularly limited, and conventional molds can be used. In addition, the mold can be heated or cooled as needed.

[0171] As the shape of the gate for introducing the resin C into the cavity, various methods such as direct gate method, disc gate method, side gate method, fan gate method, film gate method, tunnel gate method, etc. can be applied according to the shape of the joint body.

[0172] 〔Resin C〕

[0173] In this embodiment, the resin C can be used as a sealing material.

[0174] The resin C is not particularly limited as long as it can be insert molded, but is preferably made of one resin selected from thermoplastic resins, thermosetting resins, and fiber reinforced plastics (FRP). Among them, the resin C is preferably a thermoplastic resin from the viewpoint of bonding strength, cost, and ease of molding.

[0175] As thermoplastic resins, for example, thermoplastic aromatic polyesters such as polyolefins and acid-modified products thereof, polystyrene, polymethyl methacrylate, AS resin, ABS resin, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyimide, polyamide, polyamide-imide, polyetherimide, polyethersulfone, polyphenylene ether and modified products thereof, polyphenylene sulfide, polyoxymethylene, polyarylate, polyetherketone, polyetheretherketone, polyetherketoneketone, thermoplastic epoxy resins, and fiber-reinforced materials thereof, etc., can be cited. In addition, as thermosetting resins, for example, one or more resins selected from epoxy resins, vinyl ester resins, phenolic resins, polyurethane resins, etc. can be used. From the viewpoints of heat resistance, bonding strength, cost, ease of molding, etc., it is preferably made of at least one resin selected from polycarbonate, glass fiber reinforced polyamide, glass fiber reinforced polybutylene terephthalate, and glass fiber reinforced polyphenylene sulfide.

[0176] The molding temperature (resin temperature) of the resin C is preferably 100° C. to 400° C., more preferably 150° C. to 350° C., and even more preferably 180° C. to 300° C. By performing injection molding within the range of 100° C. to 400° C., the thermoplastic film B is efficiently deformed and melted by heating, and effectively wets and spreads on the bonding surface, thereby obtaining a high bonding strength.

[0177] The combination of the material of the columnar substrate A and the resin C is not particularly limited.

[0178] In the bonded body of the present embodiment, the thickness of the resin C (sealing material) is not particularly limited and can be appropriately set according to the intended use within a range in which the bonding strength and leakage resistance are excellent.

[0179] <Joint>

[0180] use Figure 5 An example of a bonded body produced by the method for producing a bonded body according to the present embodiment will be described.

[0181] Figure 5 It is a cross-sectional view formed by a section parallel to the longitudinal direction of the bonded body.

[0182] like Figure 5As shown, the bonded body 10 is formed by sealing the columnar substrate A20 with the resin C40 via the thermoplastic film B30. Since the thermoplastic film B30 is interposed, the bonding strength between the columnar substrate A20 and the resin C40 is excellent, and the adhesion is excellent. Therefore, it is possible to prevent air and the like from entering and exiting the sealed portion surrounded by the solid line, and leakage resistance can be exhibited.

[0183] The bonded body of the present embodiment exhibits excellent bonding strength even when it is a bonded body of different materials. The bonding strength is affected by many factors, such as the thickness of the thermoplastic film B, the molecular weight, chemical structure, mechanical properties, and viscoelastic properties of the polymer constituting the thermoplastic film B, in addition to the strength of the interfacial interaction between the thermoplastic film B and the columnar substrate A and between the thermoplastic film B and the resin C. Therefore, the details of the mechanism by which the bonded body of the present embodiment exhibits excellent bonding strength and leakage resistance are unclear.

[0184] In a more preferred embodiment of the bonded body, the thermoplastic film B is mainly composed of an amorphous thermoplastic resin, which is at least one of a thermoplastic epoxy resin and a phenoxy resin. The details of the mechanism by which this more preferred embodiment exhibits more excellent bonding strength and leakage resistance are not clear, but it is presumed that the main reasons are: low cohesion in the amorphous thermoplastic resin; and when hydroxyl groups exist in the resin, chemical bonds such as hydrogen bonds and van der Waals forces and intermolecular forces are formed at the interface between the thermoplastic film B and the columnar substrate A and the interface between the thermoplastic film B and the resin C.

[0185] However, in the bonded body of the present embodiment, the state or characteristics of the interface between the thermoplastic film B and the columnar substrate A and the interface between the thermoplastic film B and the resin C are difficult to analyze due to the extremely thin chemical structure below the nanometer level. Therefore, it is impossible or impractical to express by specifying the state or characteristics of the above interface to distinguish from the bonded body that does not rely on the use of the thermoplastic film B in the current technology.

[0186] In a more preferred embodiment, for example, when a leakage test is performed by applying an air pressure of 0.1 MPaG to the sealing portion of the bonded body, the air leakage amount is preferably 1 mL / min or less.

[0187] In addition, the bonded body of the present embodiment can effectively relax stress during the thermal cycle. Therefore, in a more preferred embodiment, for example, the bonded body is heated to a temperature not lower than the glass transition temperature of the thermoplastic film B and not higher than 160°C, and maintained at the temperature for 1000 minutes, and then cooled to 23°C, and then the air leakage amount when the leakage test is performed is preferably not more than 1 ml / min.

[0188] Specifically, the leakage amount is a value measured by a leakage test described in Examples.

[0189] In the joint body of the present embodiment, the columnar substrate A is firmly joined to the resin C, is not easily peeled off during the hot and cold cycle, and has excellent leakage resistance. Therefore, it can be suitably used for applications that can bring out this characteristic. For example, an electrical and electronic component can be provided, which has the joint body of the present embodiment. More specifically, a terminal block, bus bar, electrical element, etc. of an automobile, an electrical and electronic component having the joint body 10 of the present embodiment can be provided, and the joint body 10 is as follows Figure 5 As shown, the thermoplastic film B30 on the columnar substrate A20 is entirely covered with the resin C40 for sealing.

[0190] Example

[0191] Hereinafter, the present embodiment will be specifically described using Examples and Comparative Examples, but the present embodiment is not limited thereto.

[0192] In the examples and comparative examples, a bonded body was prepared by bonding the columnar substrate A, the thermoplastic film B or the bonding agent, and the resin C in this order. Hereinafter, the layer composed of the thermoplastic film B or the bonding agent is referred to as an intermediate layer.

[0193] In the examples and comparative examples, the following materials were used.

[0194] <Columnar substrate A>

[0195] C1100 (tough copper) with a width of 12.4 mm, a length of 64.9 mm, and a thickness of 1.6 mm

[0196] <Thermoplastic film B>

[0197] Films P-1 to P-14 prepared in Examples 1 to 14

[0198] <Adhesive>

[0199] Adhesives Q-1 to Q-4 prepared in Comparative Examples 1 to 4

[0200] <Resin C>

[0201] Polyphenylene sulfide (containing 30% by mass of GF)

[0202] <Weight Average Molecular Weight, Heat of Fusion, Melting Point and Epoxy Equivalent of Thermoplastic Film B and Adhesive>

[0203] (Weight average molecular weight)

[0204] The thermoplastic film B or the adhesive was dissolved in tetrahydrofuran, and the results were measured under the following conditions using Prominence 501 (manufactured by Showa Science Corporation, Detector: Shodex (registered trademark) RI-501 (manufactured by Showa Denko K.K.)).

[0205] Column: LF-804 manufactured by Showa Denko K.K. × 2

[0206] Column temperature: 40°C

[0207] Sample: 0.4 mass% tetrahydrofuran solution of resin

[0208] Flow rate: 1ml / min

[0209] Eluent: Tetrahydrofuran

[0210] Calibration method: Conversion using standard polystyrene

[0211] (Heat of Fusion and Melting Point)

[0212] 2 to 10 mg of thermoplastic film B and adhesive were weighed respectively, placed in an aluminum pan, and heated from 23°C to 200°C at 10°C / min using DSC (DSC8231 manufactured by Rigaku Co., Ltd.) to obtain a DSC curve. The heat of fusion was calculated based on the area of ​​the endothermic peak during melting of the DSC curve and the above-mentioned weighing value. In addition, the melting peak temperature of the obtained DSC curve was taken as the melting point (X°C). It should be noted that when no melting peak is obtained and the heat of fusion is less than 15 J / g, the temperature obtained by adding 70°C to the glass transition temperature is taken as the melting point (X°C). The glass transition temperature is the temperature at which the DSC curve of the second cycle of heating to 200°C, cooling to less than 40°C, and further heating to 200°C begins to decrease. It should be noted that thermosetting resins that do not melt due to heating are considered to have no melting point.

[0213] (Epoxy Equivalent Weight)

[0214] The value was measured according to JIS K-7236: 2001 and converted into a value of resin solid content. In the case of a simple mixture without reaction, it was calculated from the epoxy equivalent and content.

[0215] <Y-X(℃)>

[0216] The melting points of the thermoplastic film B and the adhesive were represented by X°C, the resin temperature of the resin C during injection molding was represented by Y°C, and the value obtained by subtracting X°C from Y°C (Y°C-X°C) was calculated.

[0217] [Example 1]

[0218] (Film P-1)

[0219] Into a reaction apparatus equipped with a stirrer, a reflux condenser, a gas introduction tube and a thermometer, 1.0 equivalent (203 g) of jER (registered trademark) 1007 (manufactured by Mitsubishi Chemical Co., Ltd., bisphenol A type epoxy resin, weight average molecular weight of about 10,000), 1.0 equivalent (12.5 g) of bisphenol S, 2.4 g of triphenylphosphine and 1,000 g of methyl ethyl ketone were added, and the temperature was raised to 100° C. while stirring under a nitrogen atmosphere. Dissolution was visually confirmed, and the mixture was cooled to 40° C. to obtain a thermoplastic epoxy resin composition having a solid content of about 20% by mass. The solvent was removed therefrom to obtain a thermoplastic epoxy resin as a solid content. A non-adhesive fluororesin film (Nitofluon (registered trademark) No. 900UL, manufactured by Nitto Denko Corporation) was set on the upper plate and the lower plate of the press, and the above-mentioned thermoplastic epoxy resin was arranged on the non-adhesive fluororesin film of the lower plate. The press was heated to 160°C and the thermoplastic epoxy resin was heated and compressed for 2 hours to obtain a film P-1 with a solid content of 100% by mass, a length of 32 to 33 mm, and a thickness and width shown in Table 1-1.

[0220] (Process 1)

[0221] An adhesive tape (manufactured by Kokuyo Co., Ltd., product number TA-DM400-08) was applied to one side of the columnar substrate A, and the film P-1 was wrapped around the columnar substrate A once so as to overlap the applied portion to form a wrapping portion of 2 to 3 mm. Figure 6 Schematic diagram of a joint body used to illustrate the embodiment. Figure 6 As shown in FIG6-1, the unbonded portion a of the film P-1(B) is provided, and the film P-1(B) is wound around the columnar substrate A(A).

[0222] Next, the columnar substrate A(A) wound with the film P-1(B) was heated at the heating temperature and heating time shown in Table 1-1 to melt the film P-1(B). Then, the film P-1(B) was solidified by cooling at room temperature for 1 minute to prepare a substrate with a film in which the columnar substrate A(A) and the film P-1(B) were bonded.

[0223] In addition, the operation method of this process 1 is shown as "winding method 1" in Table 1-1.

[0224] (Process 2)

[0225] Using an injection molding machine (manufactured by Toyo Machinery & Metal Co., Ltd., model name "Si-100-6s") and a molding mold, resin C was insert-molded and bonded to the portion of the substrate with the film P-1 (B) wound thereon, thereby obtaining a bonded body of the columnar substrate A and resin C. The insert molding conditions were as follows: injection molding temperature (resin temperature) of 300°C, mold temperature of 135°C, injection speed of 15 mm / sec, injection pressure of 130 MPa, holding pressure of 70 MPa, holding time of 4 seconds, and cooling time of 30 seconds. Figure 6 6-2 shows a schematic diagram of a bonded body of a columnar substrate A (A) and a resin C (C) obtained in step 2.

[0226] [Examples 2 to 6]

[0227] (Membrane P-2 to Membrane P-6)

[0228] Films P-2 to P-6 were obtained in the same manner as in Example 1 except that the thickness and width of the film were replaced with the values ​​shown in Table 1-1.

[0229] (Process 1 and Process 2)

[0230] Next, step 1 and step 2 were carried out in the same manner as in Example 1 under the conditions shown in Table 1-1 to obtain a bonded body of the columnar substrate A and the resin C.

[0231] [Example 7]

[0232] (Film P-7)

[0233] In Example 1, a film P-7 was obtained in the same manner as in Example 1 except that the thickness and width of the film were replaced with the values ​​shown in Table 1-1.

[0234] (Process 1)

[0235] Next, the film P-7 was wound once around the columnar substrate A so as to form a wrapping portion of 2 to 3 mm.

[0236] Next, the film P-7 portion wound around the columnar substrate A was fixed with a clamp and heated at the heating temperature and heating time shown in Table 1-1 to melt the film P-7. Then, the film P-7 was cooled at room temperature for 1 minute to solidify the film, thereby producing a substrate with a film in which the columnar substrate A and the film P-7 were bonded.

[0237] In addition, the operation method of this process 1 is shown as "winding method 2" in Table 1-1.

[0238] (Process 2)

[0239] Next, step 2 was carried out in the same manner as in Example 1 to obtain a bonded body of the columnar substrate A and the resin C.

[0240] [Example 8]

[0241] (Film P-8)

[0242] 20 g of フェノトート (registered trademark) YP-50S (manufactured by Nippon Steel Chemika & Material Co., Ltd., phenoxy resin, weight average molecular weight of about 50,000) and 80 g of cyclohexanone were added to a reaction apparatus equipped with a stirrer, a reflux condenser, a gas introduction tube and a thermometer, and the temperature was raised to 60° C. while stirring. The solution was visually confirmed, and the mixture was cooled to 40° C. to obtain a phenoxy resin composition having a solid content of 20% by mass. The solvent was removed therefrom, and the mixture was heated at 160° C. to obtain a film P-8 having a solid content of 100% by mass, a length of 33 mm, and a thickness and width shown in Table 1-2.

[0243] (Process 1 and Process 2)

[0244] Step 1 and Step 2 were carried out in the same manner as in Example 7 under the conditions shown in Table 1-2 to obtain a bonded body of the columnar substrate A and the resin C.

[0245] [Example 9]

[0246] (Membrane-9)

[0247] Film-9 was obtained in the same manner as in Example 8 except that the film width was changed to 10 mm.

[0248] (Process 1 and Process 2)

[0249] Using film P-9 instead of film P-1, steps 1 and 2 were carried out in the same manner as in Example 1 to obtain a bonded body of the columnar substrate A and the resin C.

[0250] [Example 10]

[0251] (Film P-10)

[0252] Film P-10 was obtained in the same manner as in the production of film P-8 of Example 8, except that 5% by mass (in terms of solid content) of a tackifier resin (TAMANOL 803L manufactured by Arakawa Chemical Industries, Ltd.) was added.

[0253] (Process 1 and Process 2)

[0254] Using film P-10 instead of film P-7, steps 1 and 2 were carried out in the same manner as in Example 7 to obtain a bonded body of the columnar substrate A and the resin C.

[0255] [Example 11]

[0256] (Film P-11)

[0257] Film P-11 was obtained in the same manner as in the production of film P-8 of Example 8, except that 10% by mass (in terms of solid content) of a tackifier resin (YS Polystar K125 manufactured by Yashhara Chemical Co., Ltd.) was added.

[0258] (Process 1 and Process 2)

[0259] Using film P-11 instead of film P-7, steps 1 and 2 were carried out in the same manner as in Example 7 to obtain a bonded body of the columnar substrate A and the resin C.

[0260] [Example 12]

[0261] (Film P-12)

[0262] In Example 1, the same procedures were carried out except that the thickness and width of the film were replaced with the values ​​shown in Table 1-2 to obtain a film P-12.

[0263] (Process 1)

[0264] An emulsion adhesive (Polysol (registered trademark) PSA SE-8001 manufactured by Showa Denko K.K.) was applied to one side of the film P-12 and dried at 100°C for 5 minutes. The surface of the film P-12 coated with the adhesive was wound around the columnar substrate A for one turn so as to form a wrapping portion of 2 to 3 mm, thereby preparing a substrate with a film. On the columnar substrate A, the unbonded portion of the film was provided in the same manner as in Example 1.

[0265] (Process 2)

[0266] Step 2 was carried out in the same manner as in Example 1 to obtain a bonded body of the columnar substrate A and the resin C.

[0267] [Example 13]

[0268] (Film P-13)

[0269] A crystalline polyamide hot-melt adhesive film (ELFAN (registered trademark) NT-120 manufactured by Nippon Matai Co., Ltd.) was used to prepare a film P-13 having a length of 33 mm and a thickness and width shown in Table 1-2.

[0270] In the film P-13, since it was insoluble in the solvent, the weight average molecular weight and epoxy equivalent could not be measured.

[0271] (Process 1 and Process 2)

[0272] Step 1 and Step 2 were carried out in the same manner as in Example 1 under the conditions shown in Table 1-2 to obtain a bonded body of the columnar substrate A and the resin C.

[0273] [Example 14]

[0274] (Film P-14)

[0275] As the film P-14, a polycarbonate film (Upperlon (registered trademark) sheet FE-2000 manufactured by Mitsubishi Gas Chemical Co., Ltd., thickness 100 μm) was used to prepare a film having a length of 33 mm and a thickness and width shown in Table 1-2.

[0276] (Process 1 and Process 2)

[0277] Step 1 and Step 2 were carried out in the same manner as in Example 1 under the conditions shown in Table 1-2 to obtain a bonded body of the columnar substrate A and the resin C.

[0278] [Comparative Example 1]

[0279] (Adhesive Q-1)

[0280] Into a reaction apparatus equipped with a stirrer, a reflux condenser, a gas introduction tube and a thermometer, 1.0 equivalent (285 g) of jER (registered trademark) 1001 (Mitsubishi Chemical Co., Ltd., bisphenol A type epoxy resin, molecular weight about 900), 1.0 equivalent (63 g) of Shonol (registered trademark) BRG-556 (Ika Industries Co., Ltd., novolac type phenolic resin), 1.4 g of triphenylphosphine, and 650 g of methyl ethyl ketone were placed, and the temperature was raised to 100° C. while stirring in a nitrogen atmosphere. Dissolution was visually confirmed, and the mixture was cooled to 40° C. to obtain a thermosetting epoxy resin solution (adhesive Q-1) having a solid content of 20% by mass.

[0281] (Process 1)

[0282] The above-mentioned bonding agent Q-1 was applied to the columnar substrate A and heated at 160°C for 30 minutes to cure the bonding agent. Then, the bonding agent was cooled to room temperature to form an intermediate layer composed of the bonding agent Q-1. On the columnar substrate A, the unbonded portion of the above-mentioned bonding agent was provided in the same manner as in Example 1. The width of the intermediate layer is as shown in Table 2.

[0283] In addition, the operation method of this process 1 is shown as "coating method" in Table 2.

[0284] (Process 2)

[0285] The resin C was insert-molded and bonded in the same manner as in step 2 of Example 1, thereby obtaining a bonded body of the columnar substrate A and the resin C.

[0286] [Comparative Example 2]

[0287] (Adhesive Q-2)

[0288] Into a reaction apparatus equipped with a stirrer, a reflux condenser, a gas introduction tube and a thermometer, 1.0 equivalent (285 g) of jER (registered trademark) 1001 (Mitsubishi Chemika Co., Ltd., bisphenol A type epoxy resin, molecular weight about 900), 1.0 equivalent (63 g) of Shonol (registered trademark) BRG-556 (manufactured by Ika Industries, Ltd., novolac type phenolic resin), 1.4 g of triphenylphosphine, and 650 g of methyl ethyl ketone were added, and the temperature was raised to 100° C. while stirring under a nitrogen atmosphere. The solution was visually confirmed to be dissolved, and the solution was cooled to 40° C. to obtain a solution of a thermosetting epoxy resin having a solid content of 20% by mass. The solvent was removed therefrom to obtain a solid of a thermosetting epoxy resin. A non-adhesive fluororesin film (Nito Fluor (registered trademark) No. 900UL, manufactured by Nitto Denko Corporation) was set on the upper plate and the lower plate of the press. After the above-mentioned solid was arranged on the non-adhesive fluororesin film of the lower plate, the above-mentioned press was heated to 160°C, and the above-mentioned thermosetting epoxy resin was heated and compressed for 2 hours to be cured, thereby obtaining a film Q-2 with a solid content of 100% by mass, a length of 33 mm, and a thickness and width shown in Table 2.

[0289] (Process 1 and Process 2)

[0290] Step 1 and Step 2 were carried out in the same manner as in Example 1 under the conditions shown in Table 2 to obtain a bonded body of the columnar substrate A and the resin C.

[0291] [Comparative Example 3]

[0292] (Adhesive Q-3)

[0293] Into a reaction apparatus equipped with a stirrer, a reflux condenser, a gas introduction tube and a thermometer were added 1.0 equivalent (203 g) of jER (registered trademark) 1007 (Mitsubishi Chemical Co., Ltd., bisphenol A type epoxy resin, molecular weight of about 10,000), 1.0 equivalent (12.5 g) of bisphenol S, 2.4 g of triphenylphosphine and 1,000 g of methyl ethyl ketone, and the mixture was stirred at room temperature to obtain a solution of an amorphous thermoplastic epoxy resin having a solid content of about 20% by mass (adhesive Q-3).

[0294] (Process 1 and Process 2)

[0295] Step 1 and Step 2 were carried out in the same manner as in Comparative Example 1 under the conditions shown in Table 2 to obtain a bonded body of the columnar substrate A and the resin C.

[0296] [Comparative Example 4]

[0297] (Adhesive Q-4)

[0298] Into a reaction apparatus equipped with a stirrer, a reflux condenser, a gas introduction tube and a thermometer, 0.05 equivalent (98 g) of jER (registered trademark) 1007 (manufactured by Mitsubishi Chemika, bisphenol A type epoxy resin, weight average molecular weight of about 10,000), 0.95 equivalent (238 g) of PG-100 (manufactured by Osaka Gas Chemika, fluorene skeleton epoxy resin), 1.0 equivalent (125 g) of bisphenol S, 2 g of triphenylphosphine and 1,000 g of methyl ethyl ketone were added, and the temperature was raised to 100° C. while stirring under a nitrogen atmosphere. The solution was visually confirmed to be dissolved, and the solution was cooled to 40° C. to obtain a solution of an amorphous thermoplastic epoxy resin having a solid content of about 35% by mass (adhesive Q-4). It should be noted that part of the adhesive Q-4 was insoluble in the solvent, so the weight average molecular weight and epoxy equivalent could not be measured.

[0299] (Process 1)

[0300] Step 1 was carried out in the same manner as in Comparative Example 1, except that the adhesive Q-4 was applied to the columnar substrate A and heated at 120° C. for 60 minutes and then at 180° C. for 120 minutes, to obtain a bonded body of the columnar substrate A and the resin C.

[0301] (Process 2)

[0302] The resin C was insert-molded and bonded in the same manner as in step 2 of Example 1, thereby obtaining a bonded body of the columnar substrate A and the resin C.

[0303] <Workability>

[0304] Workability was evaluated from the viewpoint of bonding process time and operability required for step 1. When a film is used in step 1, the bonding process time is shorter than when a solution is used, and liquid dripping does not occur, so the intermediate layer can be formed easily.

[0305] Therefore, the workability when using the film was evaluated as good, and was indicated as "good" in Tables 1-1, 1-2, and 2. In addition, the workability when using the solution was evaluated as extremely poor compared to the film, and was indicated as "poor" in Tables 1-1, 1-2, and 2.

[0306] <Leakage test>

[0307] like Figure 6As shown in 6-3, a hose H is inserted into the joint body obtained in each embodiment and comparative example, and an adhesive for silicone resin is applied to the joint between resin C and hose H and its periphery to seal it. A connecting plug is installed at the front end of the hose H where the joint body is not installed, and connected to a compressor. After the entire joint body at the front end of the hose with the joint body installed is sunk into the water, air X is sent into the hose H along the direction of the joint body at an air pressure of 0.1MPaG, and the bubbles in the leaking water are observed visually. This operation is performed on 10 joint bodies obtained in each embodiment and comparative example, and the adhesion between the columnar substrate A and the resin C is evaluated according to the following evaluation criteria. The evaluation results are shown in Tables 1-1, 1-2 and 2.

[0308] It should be noted that when no bubbles are observed in the water, the air leakage rate can be regarded as 1 ml / min or less.

[0309] 〈Evaluation Criteria〉

[0310] A: 10 times out of 10, no bubbles are observed.

[0311] B: No bubbles were observed 8 to 9 times out of 10.

[0312] C: No bubbles were observed 5 to 7 times out of 10.

[0313] D: No bubbles were observed 0 to 4 times out of 10.

[0314] <Leakage test after hot and cold cycles>

[0315] The bonded bodies prepared in the examples and comparative examples were subjected to 100 cycles of hot-cold cycle treatment in an atmosphere of 125°C and -40°C alternately, and then subjected to the above leakage test. The evaluation criteria were the same as those of the above leakage test.

[0316] <Leakage test after heat resistance treatment>

[0317] The bonded bodies prepared in the examples and comparative examples were left to stand in an oven at 160° C. for 1000 hours and then cooled before being subjected to the above leakage test. The evaluation criteria were the same as those of the above leakage test.

[0318] [Table 1-1]

[0319]

[0320] [Table 1-2]

[0321]

[0322] [Table 2]

[0323] Table 2

[0324]

[0325] Industrial Availability

[0326] The production method and the bonded body of the present embodiment can be used in applications such as terminals of automobiles and electric and electronic parts, bus bars, and electric components, but are not particularly limited to these exemplified applications.

[0327] Description of Reference Numerals

[0328] 1. Substrate with film

[0329] 10. Conjugate of this embodiment

[0330] 20. Columnar substrate A

[0331] 30. Thermoplastic film B

[0332] 40.40a. Resin C

[0333] 50. Mould

[0334] a. Unjoined part

[0335] b. Width of thermoplastic film B

[0336] c. Thickness of thermoplastic film B

[0337] A. Columnar substrate A

[0338] B. Thermoplastic film B

[0339] C. Resin C

[0340] H.Hose

[0341] X. Air

Claims

1. A method for producing a bonded body, which is a method for producing a bonded body produced by sequentially bonding a columnar substrate A, a thermoplastic film B, and a resin C, the method comprising the following steps in sequence: Step 1, winding the thermoplastic film B along the circumferential direction around at least a portion of the outer periphery of the columnar substrate A; and In step 2, the thermoplastic film B is sealed by bonding the resin C to the portion of the columnar substrate A where the thermoplastic film B is wound by insert molding. 2 . The method for producing a joined body according to claim 1 , wherein the thermoplastic film B has adhesiveness to the columnar substrate A. 3 . 3 . The method for producing a joined body according to claim 1 , wherein in the step 1, the columnar substrate A and the thermoplastic film B are further joined by melting and solidifying the wound thermoplastic film B.

4. The method for manufacturing a joined body according to claim 3, wherein in step 1, the columnar substrate A and the thermoplastic film B are joined by at least one method selected from contact heating, hot air heating, hot pressing, infrared heating, hot plate welding, ultrasonic welding, vibration welding and high-frequency induction welding. 5 . The method for producing a bonded body according to claim 3 , wherein in the step 1, the columnar substrate A and the thermoplastic film B are bonded at a heating temperature of 100 to 300° C. 6 . The method for producing a joined body according to claim 1 , wherein a width of the thermoplastic film B in a direction perpendicular to the circumferential direction is 3 to 30 mm. 7 . The method for producing a joined body according to claim 1 , wherein the thermoplastic film B has a thickness of 10 μm or more and 3 mm or less.

8. The method for producing a joined body according to claim 1 or 2, wherein, assuming that the melting point of the thermoplastic film B is X°C, or, in the absence of the melting point, the temperature obtained by adding 70°C to the glass transition temperature, and the resin temperature of the resin C during molding is Y°C, a value obtained by subtracting X°C from Y°C is 100 to 250°C. 9 . The method for producing a joined body according to claim 1 , wherein the thermoplastic film B contains an amorphous thermoplastic resin as a main component. 10 . The method for producing a bonded body according to claim 9 , wherein the amorphous thermoplastic resin is at least one resin selected from thermoplastic epoxy resins and phenoxy resins. 11 . The method for producing a joined body according to claim 1 , wherein the thermoplastic film B is a thermoplastic resin having an epoxy equivalent of 1,600 g / eq. or more or a thermoplastic resin containing no epoxy group. 12 . The method for producing a bonded body according to claim 1 , wherein the columnar substrate A is a metal. 13 . The method for producing a joined body according to claim 1 or 2 , wherein the resin C is a thermoplastic resin.

14. A bonded body obtained by the method for producing a bonded body according to claim 1, wherein when a leakage test is conducted by applying an air pressure of 0.1 MPaG to the sealing portion, the air leakage amount is 1 ml / min or less.

15. The bonded body according to claim 14, wherein the bonded body is heated to a temperature not lower than the glass transition temperature of the thermoplastic film B and not higher than 160°C, maintained at the temperature for 1000 minutes, and then cooled to 23°C, and then subjected to the leakage test, and the air leakage amount is not more than 1 ml / min. 16 . An electric or electronic component comprising any one selected from the group consisting of a bonded body obtained by the method for producing a bonded body according to claim 1 and the bonded body according to claim 14 .

17. The electric or electronic component according to claim 16, which is a terminal block or an electric element.

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