Manufacturing method for electronic board housing and manufacturing method for electronic control unit

Abstract

To provide a method for manufacturing an electronic board housing which has a metal member and a resin member, and has short joint process time and long open time on the condition that joint strength between both of the members is high, and a method for manufacturing an electronic control unit having the electronic board housing.SOLUTION: Provided is a manufacturing method including a pre-joint step of preparing a laminate where a metal member (2), a solid adhesive (3) containing an amorphous thermoplastic resin that is at least any one of a thermoplastic epoxy resin and a phenoxy resin as a main component, and a resin member (5) which is joined to the metal member are disposed in this order, wherein the metal base material is made of aluminum or copper, an epoxy equivalent of the amorphous thermoplastic resin is 1,600 or more, or the amorphous thermoplastic resin does not contain an epoxy group, and a fusion heat of the amorphous thermoplastic resin is 15 J / g or less.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing an electronic board housing used in an electronic control unit for an automobile, and a method for manufacturing an electronic control unit. [Background technology]

[0002] Automobiles are increasingly using a large number of electronic control units that incorporate electronic boards for electronic control of internal combustion engines and motors.

[0003] For example, as shown in FIG. 11, the housing 110 of the electronic board 150 used in the electronic control unit 160 includes a roughly container-shaped housing main body 121 that houses the electronic board 150 and has one open side (the top side in the figure), and a cover body 131 that serves as a lid that closes the open portion 121b of the housing main body 121.

[0004] In this housing 110, a heating element 155 having a heat-generating element (e.g., a semiconductor element) is mounted on an electronic board 150, and both ends of the electronic board 150 are fixed by screws 154 to boss portions 122a formed integrally and protruding from the bottom 122 of the housing main body 121.

[0005] Furthermore, in order to dissipate heat from the electronic substrate 150 (more specifically, heat from the heat generating element 155) to the outside of the housing 110, a heat sink section 111 is formed integrally with the housing main body 121 in a portion of the housing main body 121 below the heat generating element mounting section 152 of the electronic substrate 150. That is, the heat sink section 111 has a base section 112 that is in thermal contact with the lower surface of the heat generating element mounting section 152 of the electronic substrate 150 via a TIM layer (thermal interface material layer) 157, and a plurality of heat dissipation fin sections 113 that protrude from the base section 112 to the outside and below the housing main body 121, and the like, and these are formed integrally with the housing main body 121.

[0006] As the housing main body 121, one made of aluminum die-cast (for example, an inverter case made of aluminum die-cast) is generally widely used in order to improve the fuel efficiency of automobiles by reducing the weight (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-27807 Summary of the Invention [Problem to be solved by the invention]

[0008] In recent years, there has been a demand for further fuel efficiency in automobiles, and therefore there is a demand for further weight reduction in electronic circuit board housings.

[0009] Therefore, it is conceivable to assemble and manufacture the housing by using a resin material for one part and a metal material for the other part and joining the two parts together. However, in this case, the two parts must be firmly joined together to satisfy the strength required of the housing.

[0010] Furthermore, in recent years, it is preferable that, particularly in automobiles, electronic circuit board housings that include a joint between a metal member and a resin member have these two members firmly joined together.

[0011] Liquid or B-stage thermosetting epoxy resin adhesives and hot melt adhesives containing thermoplastic resins are known as means for firmly joining dissimilar materials such as metal and resin members.

[0012] However, thermosetting epoxy resin adhesives with excellent adhesive properties, whether in liquid or B-stage form, have long bonding process times or short open times.Hot melt adhesives with short bonding process times and long open times cannot stably achieve high adhesive strength.

[0013] In this disclosure, the bonding process time refers to the time from the start point when at least one of the substrates constituting the bonded body comes into contact with the bonding agent to the end point when the fabrication of the bonded body is completed. For example, the bonding process time includes the time required for the application and drying of the liquid adhesive or the placement of the solid bonding agent, and the time required to bond the substrates together (e.g., curing the adhesive layer). The shorter the bonding process time, the higher the productivity of the bonded body can be.

[0014] In this disclosure, the open time refers to the time limit from when a bonding agent is applied or placed on substrate A until substrate B is completely placed on it. Within the open time, the adhesive strength of the bonding agent does not decrease, and substrate A and substrate B can be bonded with sufficient adhesive strength. The longer the open time, the greater the degree of freedom in the manufacturing process of the bonded body.

[0015] The present disclosure has been made in consideration of the above-described technical background, and its main object is to provide a method for manufacturing an electronic circuit board housing that includes a metal member and a resin member and has a short joining process time and a long open time, on the premise that the joining strength between the two members is high. Another object of the present disclosure is to provide a method for manufacturing an electronic control unit that includes the electronic circuit board housing. [Means for solving the problem]

[0016] The present disclosure encompasses the following aspects.

[0017] [1] A pre-bonding process for preparing a laminate in which a metal member, a solid bonding agent containing as a main component an amorphous thermoplastic resin that is at least one of a thermoplastic epoxy resin and a phenoxy resin, and a resin member to be bonded to the metal member are arranged in this order; a joining step of heating and pressurizing the laminate to melt the solid adhesive and join the metal member and the resin member; A method for manufacturing an electronic substrate housing, comprising: the metal substrate is made of aluminum or copper; A method for manufacturing an electronic substrate housing, wherein the amorphous thermoplastic resin has an epoxy equivalent of 1,600 or more, or the amorphous thermoplastic resin does not contain an epoxy group and has a heat of fusion of 15 J / g or less. [2] The method for manufacturing an electronic substrate housing according to [1], wherein the heating and pressurizing are carried out under conditions of 100 to 400°C and 0.01 to 20 MPa. [3] The method for manufacturing an electronic substrate housing according to [1] or [2], wherein the solid bonding agent before melting has any shape selected from the group consisting of a film, a rod, a pellet, and a powder. [4] The method for manufacturing an electronic substrate housing according to any one of [1] to [3], wherein the metal member is made of an aluminum extrusion material and has the properties of a tensile strength of 150 MPa or more and a thermal conductivity of 150 W / (m·K) or more. [5] The method for manufacturing an electronic substrate housing according to any one of [1] to [4], wherein the metal member is made of an aluminum forged material of an A6000 series alloy and has the properties of a tensile strength of 240 MPa or more and a thermal conductivity of 180 W / (m·K) or more. [6] The method for manufacturing an electronic substrate housing according to any one of [1] to [5], wherein a first aluminum laminate film is heat-sealed in a laminated state to the inner surface of the housing body as an electromagnetic shielding layer. [7] The opening on one side of the housing body is closed with a resin cover body, The method for manufacturing an electronic substrate housing according to any one of [1] to [6], wherein a second aluminum laminate film is heat-welded in a laminated state to the inner surface of the resin cover as an electromagnetic shielding layer. [8] The opening on one side of the housing body is closed with a resin cover body, a first aluminum laminate film is heat-sealed to the inner surface of the housing body in a laminated state as an electromagnetic shielding layer; a second aluminum laminate film is heat-welded in a laminated state as an electromagnetic shielding layer to the inner surface of the resin cover body; A method for manufacturing an electronic substrate housing according to any one of [1] to [5], wherein the housing body and the resin cover body are joined by thermal welding of the first aluminum laminate film and the second aluminum laminate film while the open portion of the housing body is closed by the resin cover body. [9] A method for manufacturing an electronic control unit, comprising accommodating an electronic board in a housing body of an electronic board housing obtained by the manufacturing method described in any one of [1] to [8], and fixing the electronic board to the housing body by heat caulking an electronic board fixing protrusion formed integrally with the housing body. [Effects of the Invention]

[0018] The electronic board housing of the present disclosure includes a resin member, which allows for weight reduction of the housing. Furthermore, the present disclosure provides a method for manufacturing an electronic board housing for a vehicle that includes a metal member and a resin member and has a high bonding strength between the two members, and that has a short bonding process time and a long open time. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a schematic cross-sectional view of an electronic control unit including an electronic board housing according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic enlarged view of part A in FIG. [Figure 3] FIG. 3 is a schematic cross-sectional view of the aluminum laminate film. [Figure 4] FIG. 4 is a schematic cross-sectional view of a state in which a metal member and a resin member are bonded together via an adhesive layer containing a solid bonding agent. [Figure 5] FIG. 5 is a schematic cross-sectional view of a resin member (casing body) and a metal member (heat sink) of an electric circuit board housing according to a second embodiment of the present disclosure. [Figure 6] FIG. 6 is a schematic perspective view of a resin member (casing body) and a metal member (heat sink) of an electronic board housing according to a third embodiment of the present disclosure. [Figure 7]FIG. 7 is a schematic perspective view of the resin member and the metal member as viewed from a different direction from that of FIG. [Figure 8] FIG. 8 is a bottom view of the resin member and the metal member. [Figure 9] FIG. 9 is an end view taken along line AA in FIG. [Figure 10] FIG. 10 is an end view taken along line BB in FIG. [Figure 11] FIG. 11 is a schematic cross-sectional view of an electronic control unit equipped with a conventional electronic board housing. DETAILED DESCRIPTION OF THE INVENTION

[0020] Next, several embodiments of the present disclosure will be described below with reference to the drawings.

[0021] In this disclosure, unless otherwise specified, the term "metal" is used to include both pure metals consisting of a single metal element and alloys in which a pure metal is mixed with one or more other elements. For example, the term "aluminum" includes pure aluminum metal and its alloys.

[0022] In this disclosure, joining means connecting two objects together, and adhesion is a subordinate concept to this, and means joining two adherends (objects to be bonded) together using an organic material such as tape or adhesive (curable resin, thermoplastic resin, etc.).

[0023] The vertical direction of the electronic board housing according to the present disclosure is not limited, but in this specification and claims, in order to make it easier to understand the configuration of the electronic board housing, the vertical direction of the electronic board housing shown in Figure 1 is defined as the vertical direction of the electronic board according to the present disclosure.

[0024] As shown in FIG. 1, an electronic control unit 60 equipped with an electronic board housing 10 according to the first embodiment of the present disclosure is used, for example, to control the rotation speed of a water pump motor for an automobile, and incorporates an electronic board 50 on which a heating element 55 having an element (e.g., a semiconductor element) for controlling the rotation speed is mounted.

[0025] The electronic board housing 10 comprises a roughly container-shaped housing body 21 that houses the electronic board 50 and has one open side (the top side in the figure), a cover body 31 that serves as a lid that closes the open portion 21b of the housing body 21, and a heat sink 11 that serves as a heat dissipation member that dissipates heat from the electronic board 50 to the outside of the electronic board housing 10 (housing body 21), thereby preventing the intrusion of dust and the like from the outside and also serving to mount and fix the electronic board housing 10 to the body of an automobile, etc.

[0026] In the electronic board housing 10 of the first embodiment, the heat sink 11 is made of (the metal member 2 shown in FIG. 3), and the housing body 21 is made of (the resin member 5 shown in FIG. 3). Therefore, the heat sink 11 is made of metal, and the housing body 21 is made of resin. Furthermore, the cover body 31 is made of resin.

[0027] The housing main body 21 (resin member 5) has a bottom 22, and a plurality of upwardly protruding protrusions 22a for fixing the electronic board are integrally formed on the bottom 22. Each protrusion 22a is inserted into a fixing hole 51 provided at a corresponding end of the electronic board 50, and in this state, the electronic board 50 is fixed to the housing main body 21 by heat caulking each protrusion 22a. This makes it easy to fix the electronic board 50.

[0028] An opening 24 is provided in the bottom 22 of the housing body 21 below the heat generating element mounting portion 52 of the electronic board 50, penetrating the bottom 22 in the thickness direction. The cross-sectional shape of this opening 24 corresponds to the cross-sectional shape of the heat sink 11 (more specifically, the base portion 12 of the heat sink 11, which will be described later).

[0029] The heat sink 11 (metal member) is made of extruded aluminum and has a plate-shaped base 12 and a plurality of heat dissipation fins 13 as heat dissipation portions of the heat dissipation member. The heat dissipation fins 13 are formed integrally with the base 12 so as to protrude from the base 12.

[0030] The heat sink 11 is disposed in the opening 24 of the housing body 21 in such a manner that the heat dissipation fin portion 13 is exposed to the outside of the housing body 21 and protrudes downward, and further, the base surface 12b of the base portion 12 of the heat sink 11 (the upper surface of the base portion 12 in FIG. 1) is in thermal contact with the lower surface of the heat generating element mounting portion 52 of the electronic board 50 via a TIM layer (e.g., a thermally conductive sheet) 57. Furthermore, in this state, the housing body 21 (more specifically, the inner peripheral surface 24a of the opening 24 of the housing body 21) is joined (bonded) to the outer peripheral surface 12a of the base portion 12 of the heat sink 11, which is the contact surface of the heat sink 11 with the housing body 21.

[0031] As described above, the cover body 31 is made of resin. The type of resin is not limited, and it is, for example, polypropylene (PP).

[0032] A flange portion 32 is formed on the outer periphery of the cover body 31, and a flange portion 26 that protrudes outward from the peripheral wall portion 25 is integrally formed on the upper end of the peripheral wall portion 25 of the housing body 21. The flange portion 26 of the housing body 21 (more specifically, the flange surface 26a of the flange portion 26) and the flange portion 32 of the cover body 31 (more specifically, the flange surface 32a of the flange portion 32) are overlapped with each other, so that the open portion 21b of the housing body 21 is closed by the cover body 31. In this state, the flange portions 26, 32 are fastened together with fastening members (not shown) such as screws, thereby fixing the cover body 31 to the housing body 21.

[0033] Furthermore, as shown in FIG. 2, an aluminum laminate film 40A is heat-welded in a laminated state over the entire inner surface 31a of the cover body 31, including the flange surface 32a of the flange portion 32, as an electromagnetic shielding layer of the cover body 31.

[0034] The aluminum laminate film 40A is an integrated product of aluminum foil (including an aluminum vapor deposition layer) (see FIG. 3, reference numeral "41") and thermoplastic resin films (e.g., PP film, PET film) (see FIG. 3, reference numeral "42") laminated on both sides of the aluminum foil. The aluminum foil essentially functions as an electromagnetic shielding layer.

[0035] In the present disclosure, an aluminum laminate film (not shown) may be heat-sealed in a laminated state as an electromagnetic shielding layer for the housing body over the entire inner surface 21a, including the flange surface 26a of the flange portion 26, of the housing body 21. In this case, the aluminum laminate film not only functions as an electromagnetic shielding layer for the housing body 21, but also functions as a heat-sealed layer that joins the housing body 21 and the cover body 31 by heat welding.

[0036] That is, in this case, the flange portion 26 of the housing body 21 (more specifically, the flange surface 26a of the flange portion 26) and the flange portion 32 of the cover body 31 (more specifically, the flange surface 32a of the flange portion 32) are overlapped to close the open portion 21b of the housing body 21 with the cover body 31. In this state, the aluminum laminate film heat-welded to the flange surface 26a of one flange portion 26 and the aluminum laminate film 40A heat-welded to the flange surface 32a of the other flange portion 32 are heat-welded to each other to join the two flange portions 26, 32 (the two flange surfaces 26a, 32a). This fixes the cover body 31 to the housing body 21. This improves the joining strength between the housing body 21 and the cover body 31, simplifies the joining process between the two parts 21, 31, and does not necessarily require the use of fastening members when joining the two parts 21, 31. As a result, the number of parts in the electronic board housing 10 can be reduced.

[0037] [Method for manufacturing electronic substrate housing 10 (joint)] The method for manufacturing an electronic circuit board enclosure of the present invention includes a pre-bonding process for forming a laminate in which a metal member (hereinafter also referred to as "substrate A"), a solid adhesive agent mainly composed of an amorphous thermoplastic resin such as at least one of a thermoplastic epoxy resin and a phenoxy resin, and a resin member (hereinafter also referred to as "substrate B") to be bonded to the metal member are arranged in this order, and a bonding process for heating and pressurizing the laminate to melt the solid adhesive agent and bond the metal member to a frame body including the resin member. In the pre-bonding process, bonding between substrate A and the solid adhesive and between substrate B and the solid adhesive agent is not performed; these bonding processes are performed in the subsequent bonding process. The solid adhesive agent may have tackiness, in which case the solid adhesive agent is temporarily fixed to the substrate in the pre-bonding process.

[0038] <Pre-joining process> In the pre-bonding step, a laminate is formed in which a base material A, a solid adhesive containing as its main component an amorphous thermoplastic resin that is at least one of a thermoplastic epoxy resin and a phenoxy resin, and a base material B are arranged in this order. In the laminate, the base material A and the solid adhesive, and the solid adhesive and the base material B are not bonded to each other, and each is an independent member superimposed on top of the other.

[0039] The term "solid" in the solid adhesive means that the adhesive is solid at room temperature, i.e., has no fluidity when exposed to no pressure at 23°C. The solid adhesive is preferably capable of retaining its shape without deformation for 30 days or more when exposed to no pressure at 23°C, and is also preferably resistant to deterioration.

[0040] The "main component" means the component that is contained most abundantly among the resin components in the solid bonding agent and that accounts for 50% by mass or more of the resin components in the solid bonding agent. The solid bonding agent preferably contains 50% by mass or more of the resin component, more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more.

[0041] (Solid adhesive) The solid adhesive is primarily composed of an amorphous thermoplastic resin that is at least one of a thermoplastic epoxy resin and a phenoxy resin, and that has an epoxy equivalent of 1,600 or more and a heat of fusion of 15 J / g or less.

[0042] In this disclosure, an amorphous resin is a resin that, when measured using a differential scanning calorimeter (DSC), has a melting point (Tm) but does not have a clear endothermic peak (melting point) associated with melting, or the endothermic peak is very small. The heat of fusion is calculated from the area of ​​the DSC endothermic peak and the mass of the thermoplastic resin components. When an inorganic filler or the like is contained in the solid binder, the heat of fusion is calculated from the mass of the resin components excluding the inorganic filler. Specifically, the amorphous thermoplastic resin in this disclosure refers to the following: 2 to 10 mg of a sample is weighed out, placed in an aluminum pan, and heated using a DSC (DSC8231, manufactured by Rigaku Corporation) from 23°C to 200°C or higher at a rate of 10°C / min to obtain a DSC curve. Next, when the heat of fusion is calculated from the area of ​​the endothermic peak upon melting obtained from the DSC curve and the weighed value, a resin with a heat of fusion of 15 J / g or less is considered to be an amorphous thermoplastic resin.

[0043] In order to fully impart the properties of an amorphous thermoplastic resin to the solid bonding agent, the content of the amorphous thermoplastic resin is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and most preferably 90% by mass or more of the resin components in the solid bonding agent.

[0044] The heat of fusion is 15 J / g or less, preferably 11 J / g or less, more preferably 7 J / g or less, even more preferably 4 J / g or less, and most preferably the melting peak is below the detection limit.

[0045] The epoxy equivalent is 1,600 or more, preferably 2,000 or more, more preferably 5,000 or more, and even more preferably 9,000 or more, and most preferably above the detection limit so that epoxy groups are not substantially detected.

[0046] By using a solid adhesive primarily composed of an amorphous thermoplastic resin with an epoxy equivalent of 1,600 or more and a heat of fusion of 15 J / g or less, the adhesive does not experience the rapid viscosity drop seen with conventional hot-melt adhesives upon heating, and does not reach a low viscosity (0.001 to 100 Pa·s) even at temperatures above 200°C. Therefore, the solid adhesive does not flow out of the laminate even in a molten state, ensuring a stable adhesive layer thickness and consistently achieving high adhesive strength. The epoxy equivalent (mass of the resin containing 1 mole of epoxy groups) in this disclosure refers to the epoxy equivalent of the thermoplastic epoxy resin or phenoxy resin component contained in the solid adhesive prior to bonding, measured according to the method specified in JIS K 7236:2001 (unit: g / eq). Specifically, the epoxy equivalent of the resin is measured using a potentiometric titrator with cyclohexanone as the solvent, tetraethylammonium bromide acetate solution added to the resin, and a 0.1 mol / L perchloric acid-acetic acid solution. For solvent-diluted products (resin varnishes), the value is calculated as a solids equivalent based on the non-volatile content. The epoxy equivalent of a mixture of two or more resins can also be calculated from the content and epoxy equivalent of each resin.

[0047] The melting point of the amorphous thermoplastic resin, which is the main component of the solid adhesive, is preferably 50 to 400°C, more preferably 60 to 350°C, and even more preferably 70 to 300°C. By having a melting point in the range of 50 to 400°C, the solid adhesive can be efficiently deformed and melted by heating, effectively wetting and spreading on the adhesive surface, thereby obtaining high adhesive strength. In the present disclosure, the melting point of the amorphous thermoplastic resin means the temperature at which the resin softens from a substantially solid state, assumes a thermoplastic property, and becomes meltable and adhesive.

[0048] Bonded structures containing conventional thermosetting adhesives are difficult to disassemble, making it difficult to separate and recycle the different materials that make up the bonded structure (i.e., poor recyclability). Furthermore, when a thermosetting adhesive is used, it is difficult to reattach the bonded structure when there is misalignment of the bonded portion during the manufacturing process or when the adherend has a defect and needs to be replaced (i.e., poor repairability), resulting in a lack of convenience. On the other hand, the solid adhesive can be softened and melted by heat, allowing the two adherends to be easily separated, resulting in excellent recyclability. Furthermore, because the solid adhesive is thermoplastic, it can be reversibly softened, melted, and hardened (solidified), resulting in excellent repairability.

[0049] <Thermoplastic epoxy resin> 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 the group consisting of a phenolic hydroxyl group, a carboxyl group, a mercapto group, an isocyanate group, and a cyanate ester group. By using such a compound, the polymerization reaction to form a linear polymer proceeds preferentially, making it possible to form a thermoplastic epoxy resin with desired properties.

[0050] The (a) bifunctional epoxy resin monomer or oligomer refers to an epoxy resin monomer or oligomer having two epoxy groups in the molecule. Examples of the (a) bifunctional epoxy resin monomer or oligomer include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bifunctional phenol novolac type epoxy resins, bisphenol AD ​​type epoxy resins, biphenyl type epoxy resins, bifunctional naphthalene type epoxy resins, bifunctional alicyclic epoxy resins, bifunctional glycidyl ester type epoxy resins (e.g., diglycidyl phthalate, diglycidyl tetrahydrophthalate, dimer acid diglycidyl ester, etc.), bifunctional glycidyl amine type epoxy resins (e.g., diglycidyl aniline, diglycidyl toluidine, etc.), bifunctional heterocyclic epoxy resins, bifunctional diarylsulfone type epoxy resins, hydroquinone type epoxy resins (e.g., hydroquinone diglycidyl ether, etc.), , 2,5-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-(glycidoxyalkyl)-5,5-dialkylhydantoin, etc.), bifunctional glycidyl group-containing siloxanes (for example, 1,3-bis(3-glycidoxypropyl)-1,1,3,3-tetramethyldisiloxane, α,β-bis(3-glycidoxypropyl)polydimethylsiloxane, etc.), and modified products thereof. Among these, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, and biphenyl type epoxy resins are preferred in terms of reactivity and workability.

[0051] Examples of the (b) bifunctional compound having a phenolic hydroxyl group include mononuclear aromatic dihydroxy compounds having one benzene ring such as catechol, resorcinol, and hydroquinone; bisphenol compounds 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 having an allyl group introduced therein such as diallyl resorcinol, diallyl bisphenol A, and triallyl dihydroxybiphenyl; and dibutyl bisphenol A.

[0052] Examples of the (b) bifunctional compound having a carboxyl group include adipic acid, succinic acid, malonic acid, cyclohexanedicarboxylic acid, phthalic acid, isophthalic acid, and terephthalic acid.

[0053] Examples of the (b) bifunctional compound having a mercapto group include ethylene glycol bisthioglycolate and ethylene glycol bisthiopropionate.

[0054] Examples of the (b) bifunctional compound having an isocyanate group include diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HMDI), and tolylene diisocyanate (TDI).

[0055] Examples of the (b) bifunctional compound having a cyanate ester group include 2,2-bis(4-cyanatophenyl)propane, 1,1-bis(4-cyanatophenyl)ethane, and bis(4-cyanatophenyl)methane.

[0056] Among the compounds (b) above, bifunctional compounds having a phenolic hydroxyl group are preferred because they can form thermoplastic polymers with suitable properties, bifunctional compounds having two phenolic hydroxyl groups and a bisphenol structure or a biphenyl structure are preferred from the viewpoints of heat resistance and adhesiveness, and bisphenol A, bisphenol F, and bisphenol S are preferred from the viewpoints of heat resistance and cost.

[0057] 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 polymerizing (a) and (b) has a paraphenylene structure and ether bonds as the main backbone, a main chain connected by alkylene groups, and a structure in which hydroxyl groups generated by polyaddition are arranged in side chains. The linear structure resulting from the main backbone having the paraphenylene structure and ether bonds enhances the mechanical strength of the polymer after polymerization, and the hydroxyl groups arranged in the side chains improve adhesion to substrates. As a result, it is possible to achieve high adhesive strength on a level comparable to that of thermosetting resins while maintaining workability. Furthermore, it can be recycled and repaired by softening and melting with heat, improving the recyclability and repairability that are problems with thermosetting resins.

[0058] Phenoxy resin Phenoxy resin is a polyhydroxypolyether synthesized from a bisphenol compound and epichlorohydrin, and has thermoplastic properties. Known methods for producing phenoxy resin include a direct reaction between a dihydric phenol compound and epichlorohydrin and an addition polymerization reaction between a diglycidyl ether of a dihydric phenol compound and a dihydric phenol compound. Phenoxy resin may be obtained by either method. In the case of the direct reaction between a dihydric phenol compound and epichlorohydrin, examples of the dihydric phenol compound include phenolic compounds such as bisphenol A, bisphenol F, bisphenol S, biphenol, biphenylenediol, and fluorenediphenyl. Among these, bisphenol A, bisphenol F, and bisphenol S are preferred from the viewpoints of cost, adhesiveness, viscosity, and heat resistance. In addition to the dihydric phenol compound, an aliphatic glycol such as ethylene glycol, propylene glycol, or diethylene glycol may be used in the direct reaction. These may be used alone or in combination. Phenoxy resin has a chemical structure similar to that of epoxy resin, and has a main skeleton consisting of a paraphenylene structure and an ether bond, a main chain formed by linking these together, and hydroxyl groups arranged in side chains.

[0059] <Thermoplastic epoxy resin and phenoxy resin> The weight-average molecular weight of the thermoplastic epoxy resin and phenoxy resin, as measured by gel permeation chromatography (GPC), is preferably 10,000 to 500,000, more preferably 18,000 to 300,000, and even more preferably 20,000 to 200,000, as a polystyrene-equivalent value. The weight-average molecular weight is a standard polystyrene-equivalent value calculated from the elution peak position detected by GPC. A weight-average molecular weight within the above range provides a good balance between thermoplasticity and heat resistance, allowing efficient formation of a bonded body by melting and also improving the heat resistance of the bonded body. A weight-average molecular weight of 10,000 or more provides excellent heat resistance, while a weight-average molecular weight of 500,000 or less provides low viscosity during melting and high adhesiveness.

[0060] <Method for manufacturing solid adhesive> The method for producing the solid adhesive is not particularly limited, but it can be obtained, for example, by heating and polymerizing a difunctional epoxy compound monomer or oligomer. A solvent may be added during polymerization to reduce viscosity and facilitate stirring. If a solvent is added, it must be removed, and the solid adhesive may be obtained by drying, polymerizing, or both on a release film or the like.

[0061] If necessary, other additives can be blended into the solid binder as long as they do not impair the effects of the present invention. The amount of additives blended relative to the total volume of the amorphous thermoplastic resin is preferably 50% by volume or less, more preferably 30% by volume or less, even more preferably 20% by volume or less, and most preferably 10% by volume or less. In this disclosure, the volume percentage of additives refers to the volume ratio of the additive contained before polymerization of the bifunctional epoxy compound monomer or oligomer, based on the volume of the total volume of the amorphous thermoplastic resin. The volume of the additive can be determined by dividing the mass of the additive contained by the true specific gravity of the additive.

[0062] Examples of the additives include viscosity modifiers, inorganic fillers, organic fillers (resin powders), antifoaming agents, coupling agents such as silane coupling agents, and pigments. These additives may be used alone or in combination of two or more. Examples of viscosity modifiers include reactive diluents. Examples of inorganic fillers include spherical fused silica, metal powders such as iron, silica sand, talc, calcium carbonate, mica, acid clay, diatomaceous earth, kaolin, quartz, titanium oxide, silica, phenolic resin microballoons, and glass balloons.

[0063] The solid bonding agent thus obtained has a low content of unreacted monomers or terminal epoxy groups, or is substantially free of unreacted monomers or terminal epoxy groups, and therefore has excellent storage stability and can be stored for long periods at room temperature.

[0064] The form of the solid adhesive is not particularly limited, but it is preferably any one selected from the group consisting of film, rod, pellet, and powder. In particular, at least one side of the outer shape of the solid adhesive is preferably 5 mm or less, more preferably 3 mm or less, even more preferably 1 mm or less, even more preferably 0.5 mm or less, and most preferably 0.3 mm or less. When the size of the solid adhesive is within the above range, the solid adhesive can be sandwiched between substrate A and substrate B and can efficiently spread over the bonding surface when heated and pressurized, thereby obtaining high adhesive strength.

[0065] The solid adhesive may have tackiness to the extent that it does not impair adhesive strength and heat resistance. In this case, the solid adhesive can be temporarily fixed to the substrate in the laminate preparation step.

[0066] <Joining process> In the bonding step, the laminate is heated and pressurized to melt the solid bonding agent, and then the temperature is lowered to solidify the solid bonding agent, thereby bonding the base material A and the base material B together.

[0067] The temperature for the heating and pressurization is preferably 100 to 400° C., more preferably 120 to 350° C., and even more preferably 150 to 300° C. By heating at 100 to 400° C., the solid adhesive agent is efficiently deformed and melted, and effectively wets and spreads over the bonding surface, thereby achieving high adhesive strength.

[0068] The pressure applied during heating and pressing is preferably 0.01 to 20 MPa, more preferably 0.1 to 10 MPa, and even more preferably 0.2 to 5 MPa. Within this pressure range, the solid bonding agent efficiently deforms and effectively wets and spreads across the bonding surface, resulting in high adhesive strength. When at least one of substrate A and substrate B contains a thermoplastic resin, applying pressure at 0.01 to 20 MPa makes the solid bonding agent and the substrate compatible, resulting in high adhesive strength.

[0069] The thermoplastic epoxy resin and phenoxy resin, which are the main components of the solid adhesive, have low cohesive strength within the resin and contain hydroxyl groups, which give them strong interaction with the substrate and enable them to bond dissimilar materials with greater adhesive strength than conventional crystalline hot melt adhesives.

[0070] The bonding of the substrate A and the substrate B utilizes the phase change (solid-liquid-solid) of the solid bonding agent, and does not involve a chemical reaction, so bonding can be completed in a shorter time than with conventional thermosetting epoxy resins.

[0071] [Electronic board housing 10 (joint)] FIG. 4 is a schematic cross-sectional view of a state in which a metal member 2 and a resin member 5 are bonded via a solid adhesive, and shows the bonding area between, for example, the heat sink 11 (metal member) and the housing main body 21 (resin member) shown in FIG.

[0072] In the bonded structure shown in FIG. 4 , a metal member 2 and a resin member 5 are bonded together via an adhesive layer 3 formed by melting and solidifying a solid adhesive agent whose main component is an amorphous thermoplastic resin, such as at least one of a thermoplastic epoxy resin and a phenoxy resin. Despite the metal member 2 and the resin member 5 being dissimilar materials, the bonded structure exhibits excellent bond strength. Bond strength is influenced by numerous factors, including the strength of the interfacial interaction between the adhesive layer and the substrate, the thickness of the adhesive layer, the molecular weight and chemical structure of the polymer constituting the adhesive, mechanical properties, and viscoelastic properties. Therefore, while the details of the mechanism by which the bonded structure of the present disclosure exhibits excellent bond strength are unclear, it is speculated that the main factors are the low cohesive strength of the amorphous thermoplastic resin constituting the adhesive layer 3 and the presence of hydroxyl groups in the resin, which form chemical bonds or intermolecular forces, such as hydrogen bonds and van der Waals forces, at the interfaces between the adhesive layer and the metal member 2 and between the adhesive layer and the resin member 5. However, in a bonded structure, the state or characteristics of the interface of the bonded structure are difficult to analyze because they are due to an extremely thin chemical structure with a thickness of less than a nanometer. Therefore, it is impossible or impractical with current technology to identify the state or characteristics of the interface of the bonded structure of the present disclosure in order to distinguish it from a bonded structure that does not contain the solid bonding agent of the present disclosure.

[0073] The electronic substrate housing of the present disclosure, in which the adhesive layer contains an amorphous thermoplastic resin, is highly recyclable and repairable, and can be easily disassembled into the metal member 2 and the resin member 5 by heating the bonded body.

[0074] The resin member 5 preferably contains at least one selected from the group consisting of thermoplastic resin, thermosetting resin, and fiber reinforced plastic (FRP), and from the viewpoints of adhesive strength, cost, and ease of molding, it is more preferable that the resin member 5 contains at least one selected from the group consisting of thermoplastic resin and fiber reinforced plastic (FRP).

[0075] Examples of thermoplastic resins include polyolefins and their acid-modified products, polystyrene, polymethyl methacrylate, AS resins, ABS resins, thermoplastic aromatic polyesters such as polyethylene terephthalate and polybutylene terephthalate, polycarbonates, polyimides, polyamides, polyamideimides, polyetherimides, polyethersulfones, polyphenylene ethers and their modified products, polyphenylene sulfide, polyoxymethylene, polyarylates, polyether ketones, polyether ether ketones, polyether ketone ketones, and thermoplastic epoxy resins. Examples of thermosetting resins include epoxy resins, vinyl ester resins, phenolic resins, and urethane resins. Thermoplastic resins and thermosetting resins may be used alone or in combination of two or more.

[0076] High adhesive strength may be obtained by subjecting the metal member 2, the resin member 5, or both to an appropriate pretreatment. Pretreatments that clean the surface of the substrate or that create irregularities on the surface are preferred. Only one type of pretreatment may be used, or two or more types may be applied. Known methods can be used as specific methods for these pretreatments.

[0077] The metal member 2 is preferably subjected to at least one treatment selected from the group consisting of degreasing treatment, UV ozone treatment, blasting treatment, polishing treatment, plasma treatment, and etching treatment.

[0078] The resin member 5 is preferably subjected to at least one treatment selected from the group consisting of degreasing treatment, UV ozone treatment, blasting treatment, polishing treatment, plasma treatment, and corona discharge treatment.

[0079] Although several embodiments of the present invention have been described, the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the gist of the present invention.

[0080] Next, an electronic board housing 10 according to a second embodiment of the present disclosure will be described below with reference to Fig. 5. In Fig. 5, elements that perform the same functions as elements of the electronic board housing 10 of the first embodiment are assigned the same reference numerals as those assigned to the elements of the electronic board housing 10 of the first embodiment. Below, the second embodiment will be described, focusing on the differences from the first embodiment.

[0081] As shown in FIG. 5, in the electronic substrate housing 10 of the second embodiment, an aluminum laminate film 40 is heat-welded in a laminated manner over the entire inner surface 21a of the housing body 21 excluding the flange surface 26a of the flange portion 26 and the exposed surface 11a of the heat sink 11 exposed to the inside of the housing body 21 as an electromagnetic shielding layer for the housing body 21.

[0082] Here, the surfaces of the housing body 21 and the heat sink 11 to which the aluminum laminate film 40 is thermally welded are referred to as surfaces S of the resin member (housing body 21) and the metal member (heat sink 11) to be thermally welded by the aluminum laminate film 40.

[0083] 3, the aluminum laminate film 40 is an integrated structure of an aluminum foil (including an aluminum vapor deposition layer) 41 and thermoplastic resin films (e.g., PP film, PET film) 42, 42 laminated on both sides of the aluminum foil 41. The aluminum foil 41 essentially functions as an electron shielding layer.

[0084] A preferred method for manufacturing the electronic substrate housing 10 is to mold the resin member (housing body 21) while simultaneously joining the metal member (heat sink 11) and the resin member and heat-welding the aluminum laminate film 40 to the above-mentioned intended heat-welding surfaces S of the resin member and the metal member.

[0085] The size and thickness of the aluminum laminate film 40 are preferably set taking into consideration the surface area to which the aluminum laminate film 40 will be stretched when molding of the resin member is completed.

[0086] The aluminum laminate film 40 is not heat-welded to the flange surface 26a of the flange portion 26 of the housing body 21 (resin member).

[0087] However, although not shown in the drawings in the present disclosure, the aluminum laminate film 40 may also be heat-welded to the flange surface 32a of the flange portion 32 and the flange surface 26a of the flange portion 26 of the housing body 21. In this case, as described above, by heat-welding the aluminum laminate film 40 heat-welded to the flange surface 26a of the flange portion 26 of the housing body 21 and the aluminum laminate film 40 heat-welded to the flange surface 32a of the flange portion 32 of the cover body 31 to each other, the flange portions 26, 32 (the flange surfaces 26a, 32a) can be joined together. This allows the housing body 21 and the cover body 31 to be firmly joined, simplifies the joining of the two 21, 31, and does not necessarily require the use of fastening members when joining the two 21, 31, thereby reducing the number of parts.

[0088] Furthermore, when the aluminum laminate film 40 is heat-welded to the inner surface 31a of the cover body 31 (including the flange surface 32a of the flange portion 32), the above-mentioned preferable method can also be used.

[0089] Next, an electronic board housing according to a third embodiment of the present invention will be described below with reference to Figures 6 to 10. In these figures, elements that perform the same functions as elements of the electronic board housing according to the first embodiment are assigned the same reference numerals as those assigned to the elements of the electronic board housing according to the first embodiment. Below, the third embodiment will be described, focusing on the differences from the first embodiment.

[0090] As shown in these figures, in the electronic board housing 10 of the third embodiment, the number of heat sinks 11 is two, and the number of openings 24 provided in the housing body 21 (more specifically, the bottom 22 of the housing body 21) is the same as the number of heat sinks 11 (i.e., two). One heat sink 11 is disposed in each opening 24, and the housing body 21 (more specifically, the inner peripheral surface 24a of the opening 24 of the housing body 21) is joined (bonded) to the outer peripheral surface 12a of the base portion 12 of the heat sink 11.

[0091] As described above, in the present invention, the number of heat sinks 11 may be one or more.

[0092] Although several embodiments of the present invention have been described, the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit of the present invention.

[0093] In the above embodiment, the metal member is a heat sink, but in the present invention, the metal member is not limited to being a heat sink, and may also be, for example, a heat spreader or a reinforcing member for the housing.

[0094] Furthermore, the electronic board housing according to the present invention does not exclude a housing in which a heat dissipation member such as a heat sink is disposed in an opening provided in the cover body. [Example]

[0095] Experimental and comparative test examples related to the present invention are shown below, but the present invention is not limited to these examples. In the following examples, substrate A and substrate B are collectively referred to as the bonding substrates.

[0096] <Joining base material> The following bonding substrates were used: <PC (Polycarbonate)> SABIC 121R was injection molded to obtain test specimens with a width of 10 mm, a length of 45 mm, and a thickness of 3 mm. These specimens were used without any surface treatment. "aluminum" The surface of A6061-T6 was blasted to obtain test pieces with a width of 10 mm, a length of 45 mm, and a thickness of 3 mm.

[0097] <Weight-average molecular weight, heat of fusion, and epoxy equivalent of thermoplastic epoxy resin and phenoxy resin> The weight average molecular weight, heat of fusion and epoxy equivalent of the thermoplastic epoxy resin and the phenoxy resin were measured by the following procedures.

[0098] (Weight average molecular weight) The thermoplastic epoxy resin and the phenoxy resin were dissolved in tetrahydrofuran, and the viscosity was measured under the following conditions using Prominence 501 (manufactured by Showa Science Co., Ltd., Detector: Shodex (registered trademark) RI-501 (manufactured by Showa Denko K.K.)). Column: Showa Denko LF-804 x 2 Column temperature: 40℃ Sample: 0.4% by mass of resin in tetrahydrofuran Flow rate: 1mL / min Eluent: tetrahydrofuran Calibration method: Conversion using standard polystyrene

[0099] (heat of fusion) 2 to 10 mg of thermoplastic epoxy resin and phenoxy resin were weighed out and placed in an aluminum pan. The temperature was raised from 23°C to 200°C at a rate of 10°C / min using a DSC (DSC8231, manufactured by Rigaku Corporation) to obtain a DSC curve. The heat of fusion was calculated from the area of ​​the endothermic peak upon melting in the obtained DSC curve and the weighed value.

[0100] (epoxy equivalent) The measured values ​​obtained in accordance with JIS K 7236:2001 were converted into values ​​based on the resin solids content. In the case of simple mixtures that did not involve a reaction, the values ​​were calculated from the epoxy equivalent and content of each component.

[0101] <Test Example 1> (Solid adhesive P-1) A reactor equipped with a stirrer, reflux condenser, gas inlet tube, and thermometer was charged with 203 g (1.0 equivalent) of jER (registered trademark) 1007 (Mitsubishi Chemical Corporation, bisphenol A-type epoxy resin, weight-average molecular weight approximately 10,000), 12.5 g (1.0 equivalent) of bisphenol S, 2.4 g of triphenylphosphine, and 1,000 g of methyl ethyl ketone. The mixture was heated to 100°C with stirring under a nitrogen atmosphere. After visually confirming dissolution, the mixture was cooled to 40°C to obtain a resin composition with a solid content of approximately 20% by mass. The solvent was removed from the resin composition to obtain a 100 μm-thick film-like solid adhesive (P-1) with a solid content of 100% by mass. The weight-average molecular weight was approximately 37,000. The epoxy equivalent was above the detection limit. No heat of fusion peak was detected by DSC. (zygote) A bonded body was prepared from substrate A (metal member) and substrate B (resin member) shown in Table 1. For open time evaluation, a bonded body for open time evaluation was also prepared using the same procedure, except that the solid bonding agent was placed on the aluminum substrate (substrate A) and left to stand for 3 days, and then the PC substrate (substrate B) was placed on top.

[0102] The solid adhesive P-1, cut to a size of 10 x 15 mm, was placed on top of the base material A, and then the base material B was quickly placed on top of it. The overlapping area between these base materials was 10 mm wide and 5 mm deep. The solid adhesive P-1 was placed so as to cover the entire overlapping area between the base materials. In other words, the base materials A and B were not in direct contact with each other, but the solid adhesive was interposed between them, and an unbonded laminate was prepared. A high-frequency induction welding machine (Seidensha Electronics Co., Ltd., oscillator UH-2.5K, press JIIP30S) was used to heat the metal by high-frequency induction, and the test pieces were joined by heating and pressurization. The applied pressure was 110 N (pressure 2.2 MPa), and the oscillation frequency was 900 kHz. The oscillation time was 6 seconds.

[0103] <Test Example 2> (Solid adhesive P-2) A reactor equipped with a stirrer, reflux condenser, gas inlet tube, and thermometer was charged with 20 g of Enotote® YP-50S (Nippon Steel Chemical & Material Co., Ltd., phenoxy resin, weight-average molecular weight approximately 50,000) and 80 g of cyclohexanone. The mixture was heated to 60°C with stirring, and after visual confirmation of dissolution, the mixture was cooled to 40°C to obtain a resin composition with a solid content of 20% by mass. The solvent was removed from the resin composition to obtain a 100% solid content, 100 μm thick film-like solid adhesive (P-2). The weight-average molecular weight was 50,000, and the epoxy equivalent was above the detection limit. No heat of fusion peak was detected by DSC. (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Test Example 1, except that P-2 was used as the solid bonding agent.

[0104] <Test Example 3> (Solid adhesive P-3) The resin composition P-2 and crystalline epoxy resin YSLV-80XY (manufactured by Nippon Steel Chemical & Material Co., Ltd.) were mixed in a mass ratio of 98:2 to obtain a solid bonding agent (P-3). The weight-average molecular weight was 36,000, the epoxy equivalent was 9600 g / eq, and the heat of fusion was 2 J / g. (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Test Example 1, except that P-3 was used as the solid bonding agent.

[0105] <Test Example 4> (Solid adhesive P-4) The resin composition P-2 and crystalline epoxy resin YSLV-80XY (manufactured by Nippon Steel Chemical & Material Co., Ltd.) were mixed in a mass ratio of 94:6 to obtain a solid bonding agent (P-4). The weight-average molecular weight was 35,000, the epoxy equivalent was 2100 g / eq, and the heat of fusion was 4 J / g. (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Test Example 1, except that P-4 was used as the solid bonding agent.

[0106] <Test Example 5> (Solid adhesive P-5) The resin composition P-2 and crystalline epoxy resin YSLV-80XY (manufactured by Nippon Steel Chemical & Material Co., Ltd.) were mixed in a mass ratio of 89:11 to obtain a solid bonding agent (P-5). The weight-average molecular weight was 33,000, the epoxy equivalent was 1745 g / eq, and the heat of fusion was 11 J / g. (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Test Example 1, except that P-5 was used as the solid bonding agent.

[0107] <Test Example 6> (Solid adhesive P-6) A reactor equipped with a stirrer, reflux condenser, gas inlet tube, and thermometer was charged with 203 g (1.0 equivalent) of jER (registered trademark) 1007 (Mitsubishi Chemical Corporation, bisphenol A-type epoxy resin, molecular weight approximately 4060), 12.5 g (0.6 equivalent) of bisphenol S (molecular weight 250), 2.4 g of triphenylphosphine, and 1,000 g of methyl ethyl ketone. The mixture was heated to 100°C with stirring under a nitrogen atmosphere. After visually confirming dissolution, the mixture was cooled to 40°C to obtain a resin composition with a solid content of approximately 20% by weight. The solvent was removed from the resin composition to obtain a 100 μm thick film-like solid adhesive (P-6) with a solid content of 100% by weight. The weight-average molecular weight was approximately 30,000, and the epoxy equivalent was above the detection limit. No heat of fusion peak was detected by DSC. (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Test Example 1, except that P-6 was used as the solid bonding agent.

[0108] <Comparative Test Example 1> (Solid adhesive Q-1) Two components of the thermosetting liquid epoxy adhesive E-250 (Konishi Co., Ltd., a two-component type consisting of a bisphenol-type epoxy resin and an amine curing agent) were mixed, applied to a release film, and cured at 100°C for 1 hour. The mixture was then cooled and peeled off from the release film to obtain a 100 μm-thick solid adhesive film (Q-1). No heat of fusion peak was detected in DSC. The epoxy equivalent and weight-average molecular weight could not be measured because the material was insoluble in solvents. (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Test Example 1, except that Q-1 was used as the solid bonding agent.

[0109] Comparative Test Example 2 (Solid adhesive Q-2) An amorphous polycarbonate film (Iupilon (registered trademark) FE2000, manufactured by Mitsubishi Engineering-Plastics Corporation, thickness 100 μm) was used as the solid joint Q-2. No heat of fusion peak was detected in DSC. (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Test Example 1, except that Q-2 was used as the solid bonding agent.

[0110] Comparative Test Example 3 (Solid adhesive Q-3) Crystalline epoxy resin YSLV-80XY (manufactured by Nippon Steel Chemical & Material Co., Ltd.) was used as the solid adhesive (Q-3). The epoxy equivalent was 192 g / eq. The weight-average molecular weight was 340. The heat of fusion was 70 J / g. (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Test Example 1, except that Q-3 was used as the solid bonding agent.

[0111] Comparative Test Example 4 (zygote) Two parts of thermosetting liquid epoxy adhesive E-250 (Konishi Co., Ltd., a two-part type consisting of a bisphenol-type epoxy resin and an amine curing agent) were mixed and applied to the same substrates A and B as in Example 1, respectively, and the substrates were bonded together within one minute. The substrates were then held in place with clips and allowed to stand in an oven at 100°C for one hour to cure the adhesive components, and then cooled to room temperature to produce the bonded structure shown in Table 1. Bonded structures for open time evaluation were also produced in the same manner as above, except that the thermosetting liquid epoxy adhesive E-250 was applied to substrates A and B, respectively, and then left to stand for three days before bonding them together.

[0112] Comparative Test Example 5 A flask was charged with 203 g (1.0 equivalent) of jER (registered trademark) 1007 (Mitsubishi Chemical Corporation, bisphenol A-type epoxy resin, weight-average molecular weight approximately 10,000), 12.5 g (1.0 equivalent) 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 liquid resin composition with a solid content of approximately 20% by mass. The liquid resin composition was bar-coated onto a substrate B similar to that in Example 1, dried at room temperature for 30 minutes, and then placed in an oven at 160°C for 2 hours to form a 100 μm-thick solid thermoplastic epoxy resin polymer coating layer on the surface of the substrate B. The weight-average molecular weight of the coating layer was approximately 40,000. The epoxy equivalent was above the detection limit. No heat of fusion peak was detected by DSC. (zygote) A bonded structure shown in Table 1 was prepared in the same manner as in Experimental Test Example 1, except that substrate A was placed directly on substrate B having the coating layer. For open time evaluation, a bonded structure for open time evaluation was also prepared in the same manner as above, except that a thermoplastic epoxy resin polymer coating layer was formed on the surface of substrate B, which was then left to stand for 3 days, and then laminated with substrate A.

[0113] Comparative Test Example 6 A reactor equipped with a stirrer, reflux condenser, gas inlet tube, and thermometer was charged with 20 g of Fenotote® YP-50S (Nippon Steel Chemical & Material Co., Ltd., phenoxy resin, weight-average molecular weight approximately 50,000) and 80 g of cyclohexanone. The mixture was heated to 60°C with stirring. Dissolution was confirmed visually, and the mixture was cooled to 40°C to obtain a liquid resin composition with a solids content of 20% by mass. The liquid resin composition was bar-coated onto a substrate B similar to that in Example 1 and allowed to stand in a 70°C oven for 30 minutes, forming a 100 μm-thick phenoxy resin coating layer on the surface of substrate B. The weight-average molecular weight of the coating layer was approximately 50,000. The epoxy equivalent was above the detection limit. No heat of fusion peak was detected by DSC. (zygote) The bonded structure shown in Table 1 was prepared in the same manner as in Experimental Test Example 1, except that substrate A was placed directly on substrate B having the phenoxy resin coating layer. For open time evaluation, a bonded structure for open time evaluation was also prepared in the same manner as above, except that a phenoxy resin coating layer was formed on the surface of substrate B, which was then left to stand for 3 days, and then laminated with substrate A.

[0114] Comparative Test Example 7 (zygote) The bonded bodies and bonded bodies for open time evaluation shown in Table 1 were prepared in the same manner as in Experimental Example 1, except that a crystalline polyamide-based hot melt adhesive film NT-120 (manufactured by Nihon Matai Co., Ltd., thickness 100 μm) was used as the solid bonding agent. The heat of fusion was 60 J / g.

[0115] [Shear adhesive strength] The bonded structures obtained in Experimental Test Examples 1 to 6 and Comparative Test Examples 1 to 7 were allowed to stand at the measurement temperature (23°C or 80°C) for 30 minutes or more, and then subjected to a tensile shear adhesive strength test in an atmosphere of 23°C and 80°C in accordance with ISO 19095 using a tensile testing machine (Universal Testing Machine Autograph "AG-X plus" (Shimadzu Corporation); load cell 10 kN, tensile speed 10 mm / min) to measure the bond strength. The measurement results are shown in Table 1.

[0116] [Bonding process time] The bonding process time was measured as follows. The starting point was the contact of at least one of the substrates constituting the bonded body with the bonding agent, and the end point was the completion of the bonded body production. The heating and pressing time was calculated by averaging the heating and pressing times for each of the bonded bodies shown in Table 1.

[0117] [Recyclability] The bonded structures shown in Table 1 were placed on a hot plate at 200°C and heated for 1 minute, and then judged based on whether they could be easily peeled off with a force of 1 N or less. If all bonded structures could be peeled off, they were rated as good (OK), and if they could not be peeled off, they were rated as unsuitable (NG).

[0118] [Repairability] Of the test pieces whose adhesive surface had broken after the tensile shear strength test at 23°C (a layer of adhesive solid remained on the surface of either or both of substrates), substrate A was placed on substrate B, and a repaired bonded body was obtained by preparing a bonded body in the same manner as in Example 1. The shear adhesive strength of the repaired bonded body at 23°C was measured in the same manner as in the test method described above, and if it was 80% or more of the shear adhesive strength of the first test, it was rated as good (OK), and if it was less than 80%, it was rated as unacceptable (NG).

[0119] [Open Time Evaluation] The tensile shear adhesive strength test was carried out at 23°C using the bonded article for open time evaluation. If the shear adhesive strength was 80% or more of the test pieces prepared by the methods of the practical test example and comparative test example, it was rated as good (OK), and if it was less than 80%, it was rated as unacceptable (NG). A good open time evaluation (OK) means that the open time was long and the product was convenient to use.

[0120] [Table 1-1] [Table 1-2] [Industrial Applicability]

[0121] The present invention can be used in a method for manufacturing an electronic substrate housing, etc. [Explanation of symbols]

[0122] 2: Metal parts 3: Solid adhesive 5: Resin material 10: Electronic circuit board housing (metal material - resin material joint) 11: Heat sink (heat dissipation material) 13: Heat dissipation fin (heat dissipation part) 21: Housing body 21b: Open part 22a:Protrusion 24:Aperture 31: Cover body 50: Electronic board 60: Electronic control unit

Claims

1. a pre-bonding process for preparing a laminate in which a metal member, a solid bonding agent containing as a main component an amorphous thermoplastic resin that is at least one of a thermoplastic epoxy resin and a phenoxy resin, and a resin member to be bonded to the metal member are arranged in this order; a joining step of heating the laminate to melt the solid adhesive while maintaining the positional relationship between the metal member and the resin member, and joining the metal member and the resin member; A method for manufacturing an electronic substrate housing, comprising: In the laminate in the pre-bonding step, the metal member and the solid bonding agent, and the solid bonding agent and the resin member are not bonded to each other, and each of the metal member and the solid bonding agent is an independent member superimposed on each other, the metal member is made of aluminum or copper, A method for manufacturing an electronic substrate housing, wherein the amorphous thermoplastic resin has an epoxy equivalent of 1,600 or more, or the amorphous thermoplastic resin does not contain an epoxy group, and the heat of fusion of the amorphous thermoplastic resin is 15 J / g or less.

2. The method for manufacturing an electronic substrate housing according to claim 1, wherein the heating is carried out under conditions of 100 to 400°C.

3. 3. The method for manufacturing an electronic substrate housing according to claim 1, wherein the solid bonding agent before melting has any shape selected from the group consisting of a film, a rod, a pellet, and a powder.

4. The method for manufacturing an electronic substrate housing according to any one of claims 1 to 3, wherein the metal member is made of an aluminum extrusion material and has a tensile strength of 150 MPa or more and a thermal conductivity of 150 W / (m·K) or more.

5. The method for manufacturing an electronic substrate housing according to any one of claims 1 to 4, wherein the metal member is made of an aluminum forged material of an A6000 series alloy and has a tensile strength of 240 MPa or more and a thermal conductivity of 180 W / (m·K) or more.

6. 6. The method for manufacturing an electronic substrate housing according to claim 1, wherein a first aluminum laminate film is heat-sealed to the inner surface of the electronic substrate housing in a laminated state as an electromagnetic shielding layer.

7. The opening on one side of the electronic substrate housing is closed with a resin cover body, 7. The method for manufacturing an electronic substrate housing according to claim 1, wherein a second aluminum laminate film is heat-sealed to the inner surface of the resin cover body in a laminated state as an electromagnetic shielding layer.

8. The opening on one side of the electronic substrate housing is closed with a resin cover body, a first aluminum laminate film is heat-sealed to the inner surface of the electronic substrate housing in a laminated state as an electromagnetic shielding layer; a second aluminum laminate film is heat-welded to the inner surface of the resin cover body in a laminated state as an electromagnetic shielding layer; A method for manufacturing an electronic substrate housing according to any one of claims 1 to 5, wherein the electronic substrate housing and the resin cover body are joined by thermal welding of the first aluminum laminate film and the second aluminum laminate film while the open portion of the electronic substrate housing is closed by the resin cover body.

9. A method for manufacturing an electronic control unit, comprising: accommodating an electronic board in an electronic board housing obtained by the manufacturing method described in any one of claims 1 to 8; and fixing the electronic board to the electronic board housing by heat caulking an electronic board fixing protrusion formed integrally with the electronic board housing.

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