Manufacturing method of the joint

Abstract

To provide a method for manufacturing bonded parts that can shorten cycle times and increase production efficiency. [Solution] A method for manufacturing a bonded body in which a substrate containing metal or ceramics and a molded body containing a thermoplastic resin are directly joined, comprising: a rough surface forming step of forming a rough surface structure on the substrate joining surface; a preheating step of heating the joining surfaces of both the substrate and the molded body; and a joining step of pressing the heated joining surfaces in contact with each other to join them, wherein in the preheating step the joining surfaces are heated in a non-contact state, the molded body joining surface is heated by contact heating from the surface side, the substrate joining surface is heated in a range of -5°C or higher and +100°C or lower from the melting point temperature of the thermoplastic resin, the molded body joining surface is heated in a range of -80°C or higher and +30°C or lower from the melting point temperature of the resin, and in the joining step the substrate and the molded body are joined without heating.

Description

Technical Field

[0001] The present invention relates to a method for producing a joined body in which a base material containing a metal or ceramic and a molded body containing a thermoplastic resin are directly joined.

Background Art

[0002] A method for producing a joined body by directly joining a base material containing a metal or ceramic and a molded body containing a thermoplastic resin is known. When joining the base material and the molded body, a method (thermal welding) is performed in which a heated hot plate is brought into contact with the base material while the base material and the molded body are in contact with each other, so that the base material and the molded body are joined while the base material is heated by the hot plate. In this case, the thermoplastic resin contained in the molded body is melted by the heat applied from the base material to the molded body, and the molten thermoplastic resin achieves the joining with the base material. In this technique, it is necessary to increase the heating temperature on the base material side in order to melt the thermoplastic resin. For this reason, it becomes necessary to lengthen the cooling time until the temperature of the base material after joining decreases, leading to an extended cycle time for manufacturing the joined body. Accordingly, when joining the base material and the molded body, a preheating step is performed to heat both the base material and the molded body before joining, and after the preheating, a method of joining the base material and the molded body while heating them is carried out.

[0003] Patent Document 1 describes a method for manufacturing a metal-resin joined body, which includes a first step of exposing the surface of a synthetic resin member to a gas heated to a first temperature that is equal to or higher than the deflection temperature under load of the thermoplastic resin, and a second step of joining the surface of the synthetic resin member and the surface of the metal member. In Patent Document 1, the metal member is heated in a state where the metal member and the synthetic resin member are arranged to face each other with a gap therebetween in a gas, so that the gas present between the metal member and the synthetic resin member is heated to the first temperature by the heat of the metal member. In Patent Document 1, while heating the surface of the synthetic resin member and the surface of the metal member at a second temperature lower than the first temperature, one of the metal member and the synthetic resin member is pressed against the other to join the metal member and the synthetic resin member.

Prior Art Documents

[0004] [Patent Document 1] International Publication No. 2020 / 184440 [Overview of the project] [Problems that the invention aims to solve]

[0005] According to the method described in Patent Document 1, preheating the molded body allows for a lower heating temperature of the base material compared to heat welding. However, in order to improve production efficiency when joining the base material and the molded body, there is a need to further shorten the cycle time.

[0006] This invention has been made in view of the above prior art, and aims to provide a method for manufacturing a bonded body that can shorten the cycle time and has high production efficiency. [Means for solving the problem]

[0007] The inventors of this invention have diligently studied methods for manufacturing such a joint and have found that it can be achieved by heating the joint surface of the molded body by contact heating from the surface side in a preheating step, and by heating the joint surface of the base material and the joint surface of the molded body to a predetermined temperature range, and then joining the base material and the joint without heating (without applying heat). This led to the completion of the present invention.

[0008] In other words, the gist of the present invention is as follows: (1) A method for manufacturing a joint in which a substrate containing metal or ceramics and a molded body containing thermoplastic resin are directly joined together, The substrate has a substrate bonding surface that is joined to the molded body, The molded body has a molded body joining surface that is joined to the substrate, A surface roughening step to form a rough surface structure on the substrate bonding surface, A preheating step for heating the substrate bonding surface and the molded body bonding surface, The invention comprises a joining step of joining the substrate and the molded body by placing the heated substrate joining surface and the molded body joining surface facing each other, and applying pressure while the substrate joining surface and the molded body joining surface are in contact, In the preheating step, the substrate bonding surface and the molded body bonding surface are heated in a non-contact state with each other. In the preheating step, the joint surface of the molded body is heated by contact heating from the surface side. In the preheating step, the substrate bonding surface is heated to a range of -5°C or higher and +100°C or lower, which is the melting point of the thermoplastic resin, and the molded body bonding surface is heated to a range of -80°C or higher and +30°C or lower. In the joining process, the substrate and the molded body are joined without heating. A method for manufacturing a jointed body, characterized by the above. (2) The method for manufacturing a bonded body according to (1), wherein in the preheating step, the heating temperature of the substrate bonding surface is higher than the heating temperature of the molded body bonding surface. (3) The method for manufacturing a bonded body according to (2), wherein in the preheating step, the heating temperature of the bonded surface of the substrate is in the range of above the resin melting point temperature and above the resin melting point temperature + 50°C, and the heating temperature of the bonded surface of the molded body is in the range of above the resin melting point temperature and above the resin melting point temperature + 20°C. (4) The method for manufacturing a bonded body according to (1), wherein in the preheating step, the base material and the molded body are heated with the base material bonding surface and the molded body bonding surface facing each other. (5) The method for manufacturing a joined body according to (1), wherein the joining step is performed within 30 seconds after the preheating step. (6) The method for manufacturing a joined body according to (1), wherein the heating method for heating the molded body in the preheating step is conductive heating. (7) The method for manufacturing a bonded body according to (1), wherein in the preheating step, the heating method for heating the substrate is at least one selected from the group consisting of conduction heating, radiation heating, convection heating, high-frequency dielectric heating, microwave heating, induction heating, and laser heating. (8) The method for producing a joined body according to (1), wherein the molded body contains a filler.

Effects of the Invention

[0009] According to the method for producing a joined body of the present invention, the cycle time can be shortened, and the production efficiency can be increased.

Brief Description of the Drawings

[0010] [Figure 1] Figure 1 is a flowchart for explaining an example of the method for producing a joined body. [Figure 2] Figure 2 is a schematic cross-sectional view for explaining an example of the joined body. [Figure 3] Figure 3 is a schematic diagram for explaining an example of the preheating step. [Figure 4] Figure 4 is a schematic diagram for explaining an example of the joining step. [Figure 5] Figure 5 is a design drawing for explaining the aluminum base material used in Examples and Comparative Examples, where (a) shows a plan view and (b) shows a side view. [Figure 6] Figure 6 is a design drawing for explaining the polyphenylene sulfide (PPS) molded body used in Examples and Comparative Examples, where (a) shows a top perspective view and (b) shows a bottom perspective view.

Modes for Carrying Out the Invention

[0011] The method for producing a joined body of the present invention will be described in detail. The constituent elements of the present invention described below may be combined appropriately, in part or in whole. The dimensional ratios in the drawings may differ from the actual ratios.

[0012] [1. Method for Producing Joined Body] As shown in Figure 1, the method for producing a joined body of the present invention comprises: a roughening step S1 of forming a roughened structure on the joint surface of a base material 2 to be joined with a molded body 3 (base material joint surface); a preheating step S2 of heating the base material joint surface on which the roughened structure is formed and the molded body joint surface (the joint surface of the molded body 3 to be joined with the base material 2); and a joining step S3 of bringing the heated base material joint surface and the molded body joint surface into opposition, and applying pressure in a state where the base material joint surface and the molded body joint surface are in contact with each other, to join the base material and the molded body. In the joining step S3, the base material and the molded body are joined without additional heating. A schematic cross-sectional view of the joined body 1 in which the base material 2 and the molded body 3 are directly joined is shown in Figure 2. Herein, "direct joining" means joining in which no other layer such as an adhesive-containing layer is interposed between the base material 2 and the molded body 3. In the subsequent descriptions of the present specification, reference signs may be omitted in the explanation. Hereinafter, the base material, the molded body, the joined body, the roughening step, the preheating step, and the joining step will be described in order.

[0013] [1-1. Base Material] The base material contains a metal or a ceramic. The base material is not particularly limited as long as it contains a metal or a ceramic, and is preferably a metal base material made of metal or a ceramic base material made of ceramic. The type of metal or ceramic is not limited, and can be determined based on the application of the joined body formed using the same, and various properties and physical properties such as strength, corrosion resistance, and workability required for the application. Further, as the base material, a processed material obtained by appropriately processing into a desired shape, or a combined material obtained by appropriately combining these processed materials and the like can be used. Although it also depends on the intended use, a base material having a thickness (height from the joint surface) of generally about 0.3 mm to 100 mm is usually used.

[0014] The metal constituting the metal base material is not limited as long as it is suitable for the intended use and can be heated by the heating method described later. For example, aluminum, titanium, iron, copper, nickel, chromium and the like can be used. Further, the metal base material may be composed of an alloy made of two or more metals, such as aluminum alloy, stainless steel, titanium alloy, iron alloy (steel material), copper alloy, nickel alloy, and chromium alloy.

[0015] Furthermore, the ceramics constituting the ceramic substrate are not limited, but for example, nitride-based ceramics, oxide-based ceramics, carbide-based ceramics, etc., can be used. Specifically, examples include aluminum nitride, silicon nitride, titanium nitride, boron nitride, SiAlON, titanium carbonitride, aluminum oxide, titanium oxide, boron oxide, silicon carbide, etc., and may contain one or more of these.

[0016] [1-2. Molded product] The molded article is formed from a resin composition containing a thermoplastic resin. While not limited, it is preferable that the resin constituting the molded article be a thermoplastic resin. The thermoplastic resin included in the molded article can be appropriately selected from known thermoplastic resins depending on the application. Examples include polyamide resins (aliphatic polyamides such as PA6 and PA66, aromatic polyamides), copolymers containing styrene units such as polystyrene, ABS resin, and AS resin, copolymers containing polyethylene and ethylene units, copolymers containing polypropylene and propylene units, other polyolefins, polyvinyl chloride, polyvinylidene chloride, polycarbonate resins, acrylic resins, methacrylic resins, polyester resins, polyacetal resins, and polyphenylene sulfide resins. One or more of these thermoplastic resins can be used. Among these, polyamide resins and polyphenylene sulfide (PPS) resins are preferred because they have high fluidity during resin molding and easily penetrate the rough surface structure formed on the substrate, as described later.

[0017] Here, the molded body joining surface is the region of the molded body where the base material and the molded body are to be joined. It may be just a part of one surface of the molded body, the entire surface, or parts or all of both surfaces. Depending on the application, the joining surface should be formed in the necessary parts. Furthermore, there are no limitations on the shape, size, or arrangement of the joining surface.

[0018] Furthermore, the molded body may contain fillers. That is, the thermoplastic resin (thermoplastic resin composition) before molding the molded body may contain fillers. By including fillers in the thermoplastic resin and its molded body, the physical properties of the molded body, such as its mechanical strength, can be improved. The fillers are not limited and can be any known type. For example, fillers can be in the form of elongated fibrous or needle-like structures; particulate; or flake-like structures. Examples include glass fibers, carbon fibers, and natural fiber fillers. Preferably, the filler is a fibrous filler made of glass fibers (glass fiber). In the preheating step described later, the molded body may be heated, and a desired filler may be included to generate heat according to the heating method.

[0019] As in the method of the present invention, performing a preheating step described later, in which the substrate bonding surface and the molded body bonding surface are each heated within a predetermined temperature range, is particularly preferable when the molded body contains filler. That is, in the bonding step after the preheating step, when the substrate and the molded body are brought into contact and pressurized, the melting of the thermoplastic resin proceeds from the surface of the molded body bonding surface in the depth direction. In a configuration in which the molded body contains filler, if the molded body is brought into contact with a heated substrate without preheating the molded body bonding surface, and the molded body is heated while bonding, the resin on the surface portion in contact with the substrate melts first, and then the filler moves later, resulting in the filler being concentrated on the molded body bonding surface. At this time, in the part where the filler is concentrated, the strength of the resin on the molded body bonding surface decreases, and the strength of the joint between the substrate and the molded body decreases. In contrast, according to the method of the present invention, the molded body bonding surface can be heated to a certain extent in the depth direction in advance by performing preheating. When the bonding surface of the substrate and the bonding surface of the molded body are brought into contact and pressurized in this state during the bonding process, the resin and filler move simultaneously at the bonding surface of the molded body. This reduces the concentration of the filler at the bonding surface of the molded body, thereby suppressing the decrease in strength at the joint between the substrate and the molded body.

[0020] [1-3.Zygote] The bonded body is formed with the thermoplastic resin embedded in the rough surface structure of the bonding surface on the substrate surface, and the substrate and the molded body are integrally bonded via the bonding surface. The bonded body may be formed using one substrate and one molded body each, or multiple sets of either or both may be used, or even multiple sets of either set or both may be arbitrarily laminated, and the configuration can be appropriately determined according to the application.

[0021] For example, the joined body may be formed by joining a base material and a molded body in a stacked or continuous arrangement. Alternatively, the joined body may be formed by joining a base material, a molded body, and another base material in a stacked or continuous arrangement in that order. Alternatively, the joined body may be formed by joining a molded body, a base material, and another molded body in a stacked or continuous arrangement in that order.

[0022] When the joint joins two or more substrates via a molded body, it may include a molded body formed from a thermoplastic resin sandwiched between the substrates. Alternatively, the substrates may be joined via the adhesive, using an adhesive containing a thermoplastic resin as the molded body.

[0023] [1-4. Surface Roughening Process] In the surface roughening process, a rough surface structure is formed on the substrate bonding surface, which is the bonding surface between the substrate and the molded body. Here, the substrate bonding surface is the area of ​​the substrate where the bonding between the substrate and the molded body is planned, and it may be just a part of one surface of the substrate, the entire surface, or parts or all of both surfaces, etc. Depending on the application, the bonding surface can be formed only in the necessary parts. Furthermore, there are no limitations on the shape, size, arrangement, etc. of the bonding surface. The same applies when the substrate is a composite material, etc.

[0024] Furthermore, a rough surface structure refers to a surface structure in which the surface of the substrate has multiple irregularities, making it rougher than a smooth surface. By forming a rough surface structure with multiple irregularities on the surface of the substrate, when joining it to a molded body, the molten thermoplastic resin contained in the molded body fills into the rough surface structure, resulting in an anchoring effect. This makes it easier to improve the quality of the joint, such as the joint strength and airtightness of the joined body.

[0025] The process for forming the rough surface structure is not limited, and known methods such as irradiation with a continuous-wave laser, irradiation with a pulsed-wave laser, etching, blasting, and cutting can be used. Here, as an example of a method for forming a rough surface structure and the degree of that rough surface structure, for example, the laser irradiation treatment and laser treatment conditions described in Japanese Patent Application Publication No. 2023-59622, as well as the aperture diameter (D), depth (L), and aspect ratio (L / D) of the macro-relief portion formed thereby, can be used as reference for a method for forming a rough surface structure on a metal substrate. Furthermore, known methods such as irradiation with a continuous-wave laser, irradiation with a pulsed-wave laser, blasting, and cutting can be used to form a rough surface structure on a ceramic substrate.

[0026] [1-5. Preheating Process] In the preheating step, the substrate bonding surface, which has a rough surface structure formed on its surface, and the molded body bonding surface are heated within a predetermined temperature range, prior to the bonding step described later, while the substrate and the molded body are not in contact with each other. The state of the substrate and the molded body being not in contact with each other means that the substrate and the molded body are separated and physically apart without contact. In the preheating step, the substrate and the molded body are heated in this state. Furthermore, in this invention, the molded body bonding surface is heated by contact heating from the surface side.

[0027] An example of the preheating process is shown in Figure 3. Specifically, as shown in Figure 3, the molded body 20 is restrained using a restraining jig 60 and set in a predetermined position, while the molded body heating jig 30 is brought into contact with the molded body joining surface 21 and heated. Note that in Figure 3, the specific restraining means for restraining the molded body 20 with the restraining jig 60 are omitted from the illustration. This restraining mechanism can be realized, for example, by a clamping mechanism that fixes the molded body 20. The restraining jig 60 may have a base that makes it movable. Meanwhile, while setting the base material 10 in a predetermined position, the base material heating jig 40 is heated on the base material joining surface 11 by contact heating and / or non-contact heating. Figure 3 shows the state in which the base material joining surface 11 is heated by contact heating. At this time, a base material installation jig 50 for installing the base material 10 can be provided on the surface 12 of the base material 10 opposite to the base material joining surface 11. In the preheating process, the base material 10 may be heated from the side 12 opposite to the base material joining surface 11 using the base material mounting jig 50. The base material mounting jig 50 can also be used to restrain the base material 10, to keep the base material 10 warm, or to apply pressure during joining. The base material mounting jig 50 may have a base or the like to make it movable. Furthermore, as long as the type, performance, shape, size, etc. of jigs such as the molded body heating jig 30, the base material heating jig 40, the base material installation jig 50, and the restraining jig 60 are not impaired, they may be selected and used as appropriate.

[0028] <Heating the joint surface of the molded body> Heating of the molded body joining surface is performed by contact heating. While there are no limitations as long as the heating temperature of the molded body joining surface described later can be achieved, contact heating can be performed by conduction heating by bringing a heated molded body heating jig into contact with the molded body joining surface. When heating of the molded body joining surface is performed by contact heating, the heating jig may be heated by direct heating or by indirect heating. For direct heating, for example, high-frequency dielectric heating, microwave heating, resistance heating, induction heating, arc heating, etc. can be used. For indirect heating, for example, conduction heating, radiation heating, convection heating, laser heating, etc. The shape of the molded body heating jig is not particularly limited as long as it can contact and heat the molded body joining surface, but for example, block-shaped, plate-shaped, column-shaped, rod-shaped, etc. can be used. As for the material of the molded body heating jig, metal is preferred from the viewpoint of easy heating of the jig itself due to its low specific heat, easy heating of the molded body due to its high thermal conductivity, and excellent heat resistance due to its high melting point, with aluminum and copper being more preferred. As an example of a molded body heating jig, one can be used that is in the shape of an aluminum block or thick plate, has a built-in electric heater, and receives heating by conductive heating from the electric heater.

[0029] By applying contact heating to the joint surface of the molded body, it is possible to melt the thermoplastic resin near the joint surface that contributes to bonding with the substrate, compared to heating the entire molded body. At the same time, heating of the thermoplastic resin other than the joint surface of the molded body can be suppressed, thereby reducing deformation of the molded body during bonding.

[0030] The heating temperature of the molded joint surface shall be within the range of -80°C (the melting point of the thermoplastic resin contained in the molded body) to +30°C (the melting point of the resin). In other words, the heating temperature of the molded joint surface shall be within the range of -80°C (the melting point of the resin) to +30°C (the melting point of the resin), which is centered around the melting point of the resin and shifted towards the lower end.

[0031] The heating temperature of the molded body joining surface is preferably 50°C or higher than the resin melting point, more preferably 30°C or higher than the resin melting point, and even more preferably 10°C or higher than the resin melting point. By setting the heating temperature of the molded body joining surface to be above the lower limit of the above, when the substrate and the molded body are joined in the joining process, the molded body melts due to the heat from the substrate, making it easier to fill the rough surface structure of the substrate with the molten resin (thermoplastic resin contained in the molded body). Furthermore, since the molded body melts easily without raising the heating temperature of the substrate joining surface, the heating temperature of the substrate joining surface can be suppressed, shortening the cooling time of the substrate after joining and making it easier to reduce the cycle time of the joined body manufacturing. On the other hand, the heating temperature of the molded body joining surface is preferably 25°C or lower than the resin melting point, more preferably 20°C or lower than the resin melting point, and even more preferably 10°C or lower than the resin melting point. By keeping the heating temperature of the molded body joining surface below the above upper limit, it is possible to avoid the molded body becoming excessively hot. Furthermore, when heating the molded body joining surface by contact, it is possible to prevent the molded body from melting when in contact with the heating jig, and to prevent the molten thermoplastic resin from adhering to the jig and contaminating it.

[0032] In this invention, the resin melting point temperature is measured as follows: The temperature of the peak of the endothermic peak observed when the thermoplastic resin contained in the molded body is measured using differential scanning calorimetry (DSC) with a heating condition of 5°C / min is used. Furthermore, if multiple endothermic peaks are observed in the DSC measurement, the temperature of the higher endothermic peak is used for the resin melting point temperature. By using the resin melting point temperature obtained by this method, it becomes possible to use it not only for the specific melting point corresponding to the resin type, but also as a standard for determining the heating temperature of the molded body joining surface as described above, even when, for example, the details of the resin are unknown, multiple resins are mixed, or components other than resin (e.g., fillers) are mixed. In addition, by using the temperature of the higher endothermic peak, melting of both resins contained in the molded body becomes more likely, and when the substrate and the molded body are brought into contact during the joining process, the molten resin fills the rough surface structure of the substrate, making it easier to join them.

[0033] Furthermore, there is no limit to the time required to heat the joint surface of the molded body (contact heating time), but it is generally preferable to be 1 minute or less, more preferably 30 seconds or less, even more preferably 15 seconds or less, and particularly preferably 10 seconds or less. If the heating time is within this range, it becomes easier to reduce the cycle time of joint manufacturing. The heating time refers to the time spent in contact with the surface being heated, and does not include operations before and after heating (such as heating operations or movement time of equipment, workpieces, jigs, etc.).

[0034] The heating temperature of the molded joint surface refers to the surface temperature of the heated molded joint surface. There are no restrictions on the method of measuring the heating temperature of the molded joint surface, and known methods can be used, but from the viewpoint of accurately and instantaneously detecting the temperature, thermocouples or radiation thermometers can be used.

[0035] <Heating the bonding surface of the substrate> Heating of the substrate bonding surface is performed by contact heating and / or non-contact heating. Heating of the substrate bonding surface may be direct or indirect. The heating of the substrate bonding surface is not limited as long as the heating temperature of the substrate bonding surface described later can be achieved, and can be appropriately selected depending on the type of substrate, heating method, and jig used for heating. For example, contact heating (conduction heating) by contact with a heated hot plate is used, similar to the bonding surface of a molded body. Other examples include radiant heating, which heats by irradiating with infrared rays emitted from an infrared heater or heated hot plate; convection heating, which heats a medium such as air between the substrate and the molded body and heats the substrate bonding surface through that medium; high-frequency dielectric heating using a high-frequency electric field; microwave heating by irradiation with microwaves; induction heating, which heats by electromagnetic induction generated by passing an alternating current; and laser heating by irradiation with laser light. When heating of the substrate bonding surface is performed by indirect heating using a heated substrate heating jig, the heating of the substrate heating jig may be performed by direct heating or indirect heating. The heating, shape, and material of the base material heating jig can be the same as those described for the molded body heating jig in the section on heating the joint surface of the molded body.

[0036] The heating temperature of the substrate bonding surface shall be within the range of -5°C or higher and +100°C or lower of the melting point of the thermoplastic resin contained in the molded body. In other words, the heating temperature of the substrate bonding surface shall be within the range of a temperature near the melting point of the resin, with a lower limit of a temperature slightly below the melting point of the resin, and an upper limit of a temperature 100°C higher than the melting point of the resin.

[0037] The heating temperature of the substrate bonding surface is preferably above the resin melting point temperature, more preferably above the resin melting point temperature + 10°C, and even more preferably above the resin melting point temperature + 20°C. By setting the heating temperature of the substrate bonding surface to be above the lower limit of the above, when the substrate and molded body are bonded in the bonding process, heat from the substrate is applied to the molded body, causing it to melt and filling the rough surface structure of the substrate with molten resin (thermoplastic resin contained in the molded body). This makes it easier to improve bonding quality, such as bonding strength and airtightness, even without heating in the bonding process. On the other hand, the heating temperature of the substrate bonding surface is preferably below the resin melting point temperature + 80°C, more preferably below the resin melting point temperature + 60°C, and even more preferably below the resin melting point temperature + 50°C. By setting the heating temperature of the substrate bonding surface to be below the upper limit of the above, the cooling time of the substrate after bonding is shortened, making it easier to reduce the cycle time of the bonded body manufacturing. In addition, it is possible to avoid the substrate becoming excessively hot, and when the substrate and molded body are bonded in the bonding process, it is possible to avoid deformation of parts of the molded body other than the bonding surface due to the heat of the substrate. Furthermore, it is possible to prevent the resin from melting and adhering to and contaminating parts of the molded body other than the joint surface, such as jigs that come into contact with parts other than the joint surface (for example, jigs that restrain the molded body).

[0038] Furthermore, there is no limit to the time required for heating the substrate bonding surface (contact heating and / or non-contact heating time), but it is generally preferable to be 1 minute or less, more preferably 30 seconds or less, and even more preferably 15 seconds or less. If the heating time is within this range, it becomes easier to reduce the cycle time of manufacturing the bonded body. The heating time refers to the time spent heating by contact and / or non-contact, excluding operations before and after heating (heating operations, movement time of equipment, workpieces, jigs, etc.). In this case, the timing of the end of heating of the substrate bonding surface may differ from the timing of the end of heating of the molded body bonding surface as described above, but from the viewpoint of controlling the temperatures of the molded body bonding surface and the substrate bonding surface to facilitate bonding at the desired temperature, it is preferable that the time difference between the end of heating of the two surfaces be as small as possible, and it is more preferable that the end of heating of the two surfaces be simultaneous. Furthermore, in order to reduce the cycle time of manufacturing the bonded body, the timing of the start of heating of the substrate bonding surface may differ from the timing of the start of heating of the molded body bonding surface as described above, but it is preferable that the time difference between the start of heating of the two is as small as possible, and it is more preferable that the start of heating of both be simultaneous.

[0039] The heating temperature of the substrate bonding surface refers to the surface temperature of the heated substrate bonding surface. The same method as for measuring the heating temperature of the molded body bonding surface can be used.

[0040] In the preheating step, it is preferable that the preheating temperature of the substrate bonding surface is higher than the preheating temperature of the molded body bonding surface. This allows the temperature of the molded body to be kept down during preheating to prevent molten resin from adhering to the jig, while during bonding of the substrate and the molded body, the molded body melts and is more easily bonded by receiving heat from the substrate. Furthermore, it is even more preferable to heat both the preheating temperature of the substrate bonding surface and the preheating temperature of the molded body bonding surface within the aforementioned preferred preheating temperature ranges, while keeping the preheating temperature of the substrate bonding surface higher than the preheating temperature of the molded body bonding surface. Even more preferable is to keep the preheating temperature of the substrate bonding surface higher than the preheating temperature of the molded body bonding surface, and to keep the heating temperature of the substrate bonding surface in the range of above the resin melting point and below the resin melting point + 50°C, and the heating temperature of the molded body bonding surface in the range of above the resin melting point and below the resin melting point + 20°C. In particular, this makes it possible to suppress the upper limit of the heating temperature of the substrate bonding surface, shorten the cooling time of the substrate, and reduce the cycle time of the bonded body manufacturing.

[0041] Furthermore, in the preheating step, it is preferable to heat the substrate and the molded body with the substrate joining surface and the molded body joining surface facing each other. By heating the joining surfaces in a positional relationship facing each other in the preheating step, the joining surfaces that were facing each other can be brought closer together in the next joining step to join them. In addition, it is easier to align the substrate and the molded body for joining after the preheating step, which leads to a reduction in cycle time.

[0042] [1-6.Joining process] In the joining process, the heated substrate joining surface and the molded body joining surface are brought into contact and pressurized to join the substrate and the molded body. At this time, the resin on the molded body joining surface melts due to the heat from the substrate, and the molten resin fills the rough surface structure of the substrate. As a result, a joined body is obtained in which the substrate and the molded body are joined via their respective joining surfaces.

[0043] The joining process is preferably carried out promptly after the preheating process. By performing the joining process promptly after the preheating process, the substrate and molded body, which were heated to a predetermined temperature range during the preheating process, can be joined before their temperatures drop. For example, it is preferable that the joining process be carried out within 30 seconds after the preheating process.

[0044] An example of the joining process is shown in Figure 4. Specifically, as shown in Figure 4, the molded body heating jig 30 and the base material heating jig 40 used in the preheating process are moved, for example, away from the molded body joining surface 21 and the base material joining surface 11, respectively, so that the joining surfaces are not heated (unheated). Next, the molded body 20 and the base material 10 are positioned with their respective joining surfaces facing each other, and are moved closer together, so that the base material joining surface 11 and the molded body joining surface 21 are in contact and pressure is applied to join the base material 10 and the molded body 20. At this time, for example, the base material setting jig 50 and the restraining jig 60 may be used as needed, or they may be moved and removed. However, the base material setting jig 50 and the restraining jig 60 must be kept in a state where they are not heated (unheated) during the joining process. In Figure 4, when the molded body 20 and the base material 10 are brought into contact, the base material mounting jig 50 and the restraining jig 60 are not heated.

[0045] In other words, in this invention, the substrate and the molded body are joined without heating. Here, "non-heating" joining means that the substrate and molded body are not directly or indirectly heated. In the preheating process, the substrate and molded body are heated directly and / or indirectly, whereas in the joining process, the substrate and molded body are joined without direct or indirect heating. For example, in this joining process, not only are no operations performed to intentionally (forcibly) heat the substrate joining surface, the molded body joining surface, or any parts other than those joining surfaces, but operations are also performed not to intentionally (forcibly) heat other jigs (e.g., pressure jigs) that are in contact with the substrate and molded body. In the present invention, since the substrate and molded body are joined non-heatingly in the joining process, the temperature of the substrate after joining (immediately after joining) can be suppressed because there is no heating during joining, thus shortening the cooling time until the temperature of the substrate decreases and making it easier to reduce the cycle time.

[0046] The method of applying pressure during joining is not limited, but for example, a pressure jig may be used. For example, one method is to press with a press device from one or both sides while the base material joining surface and the molded body joining surface are in contact. The pressure applied is not limited, and should be sufficient to ensure a secure bond without deformation or damage to the base material or molded body, but for example, preferably 0.1 MPa or more and 20 MPa or less, more preferably 0.2 MPa or more and 10 MPa or less, and even more preferably 0.3 MPa or more and 20 MPa or less. There are no restrictions on the time for applying pressure during joining, but for example, it can be between 1 and 300 seconds, and preferably between 30 and 90 seconds.

[0047] Furthermore, after applying pressure while the substrate and molded body are joined, the pressure is released. At this time, the substrate and molded body may be cooled while under pressure or while the pressure is released. In particular, in order to reduce the time it takes for the temperature of the substrate to decrease, it is preferable to start cooling the substrate while under pressure before releasing the pressure. Cooling methods include natural cooling while maintaining the substrate and molded body in an unheated state, or forced cooling. For example, cooling methods such as forced air cooling or contact with a cooled metal jig can be used.

[0048] [2. Effects] As described above, in the present invention, the substrate bonding surface is heated to a temperature range of -5°C or higher and +100°C or lower, with a lower limit near the resin melting point and an upper limit of 100°C above the resin melting point. In addition, the molded body bonding surface is heated to a temperature range of -80°C or higher and +30°C or lower, with the resin melting point as the center and the lower end. In this invention, during contact-type preheating in which the molded body heating jig and the molded body joining surface are in contact, the molded body in contact with the preheating jig melts, preventing thermoplastic resin from adhering to the jig and contaminating it. Furthermore, in the joining process, the upper and lower temperature limits of the molded body during preheating are set so that the molded body is pressurized while in contact with the preheated substrate, allowing it to melt from the heat of the substrate and fill the rough surface structure of the substrate with molten thermoplastic resin.

[0049] On the other hand, the thermoplastic resin contained in the molded body, which is preheated at the aforementioned temperature, is melted by applying heat from the substrate when pressure is applied while the substrate and the molded body are in contact. The molten resin fills the rough surface structure of the substrate, so that the substrate and the molded body are joined even without heating during joining. The lower limit temperature of the substrate is set in this manner. In addition, the upper limit temperature of the substrate is set to prevent deformation of parts of the molded body other than the joining area during the joining process due to the substrate becoming excessively hot.

[0050] Therefore, according to the present invention, the substrate and the molded body are joined while preventing contamination of the jig by contact-type preheating, and since there is no heating during joining, it is easier to suppress the temperature of the substrate after joining (immediately after joining) when a predetermined time has elapsed since the start of joining, thereby shortening the cooling time until the temperature of the substrate decreases and making it easier to reduce the cycle time.

[0051] In this process, when joining a molded body and a base material by applying pressure while they are in contact, the temperature of the base material needs to have decreased to the point where the resin of the molded body has solidified by the time the pressure is released after a predetermined period of time has elapsed since the start of joining. In conventional heat welding, a hot plate is used as a base material mounting jig to hold the base material, and the base material and the molded body are joined while the base material is heated by the hot plate, requiring the base material to be heated to a relatively high temperature by the hot plate. In this case, the temperature of the hot plate in contact with the base material needs to have decreased to the point where the resin of the molded body has solidified by the time the pressure is released. Therefore, both the time required to raise the temperature of the hot plate, which had decreased in the previous cycle, and the time required to lower the temperature of the heated base material and hot plate become long, resulting in a long cycle time required for manufacturing the joined body.

[0052] In contrast, in the present invention, the molded body and the substrate are heated in a preheating step, and the heating temperatures of the molded body joining surface and the substrate joining surface are set within the above-mentioned range, with no heating during joining. As a result, according to the present invention, joining can be performed with a relatively low heating temperature of the substrate joining surface, and the time required to raise the temperature of the substrate heating jig and substrate mounting jig before joining, and the time required to lower the temperature of the substrate and substrate mounting jig during joining are shortened, thereby shortening the cycle time required for manufacturing the joined body.

[0053] Furthermore, by preheating the joint surface of the molded body through contact, it is possible to melt the thermoplastic resin near the joint surface that contributes to bonding with the substrate, compared to heating the entire molded body. In this case, heating of the thermoplastic resin other than the joint surface of the molded body can be suppressed, thereby suppressing deformation of the molded body during bonding. [Examples]

[0054] Preferred embodiments of the present invention will be specifically described below based on examples and comparative examples, but the present invention shall not be construed as being limited thereto.

[0055] [Example 1] [1. Manufacturing of the joint] <Surface roughening process (laser treatment method)> As the substrate, an A6063T5 aluminum substrate 110, as shown in Figure 5, was used. The aluminum substrate 110 is a roughly rectangular plate material with dimensions of 75 mm in length, 150 mm in width, and 2 mm in thickness when viewed from above. One side of the aluminum substrate 110 becomes the joining surface 111, and the other side becomes the opposite side 112. Laser light was irradiated concentrically at an irradiation interval of 0.09 mm in a range of 3 mm inward from the outermost edge of the substrate. The laser irradiation device used was a Keyence laser marker MDF-5200. The specifications of the device are a pulsed fiber laser, wavelength 1090 nm, maximum output 50 W, and beam diameter 60 μm. The laser conditions were output 42.5 W (85%), irradiation interval 90 μm, scanning speed 340 mm / s, and frequency 60 kHz.

[0056] As shown in Figures 6(a) and 6(b), the resin molded body 120 used in this embodiment has a cavity 121 inside, an upper surface portion 122 that covers the cavity 121, side wall portions 123 that descend from the upper surface portion 122 and surround the cavity 121, and an opening 124 formed by the ends of the side wall portions 123, through which the cavity 121 opens to the outside. When viewed from above, the side wall portion 123 is approximately rectangular in shape, measuring 76 mm in length, 151 mm in width, and with a wall thickness (width) of 3 mm. The side wall portion 123 has cylindrical pipe portions 126 (126a, 126b) on two opposing sides. The pipe portions 126 (126a, 126b) penetrate the side wall portion 123 and connect the cavity 121 inside the resin molded body 120 to the outside. The pipe section 126 (126a, 126b) has a diameter of approximately 20 mm. An open end face 125 with a width of 3 mm is provided at the lower end surface of the opening 124 of the side wall section 123. The open end face 125 serves as the joining surface for the resin molded body. The resin molded body 120 was manufactured by injection molding of PPS manufactured by DIC Corporation.

[0057] <Preheating process, joining process> In this embodiment, a hot plate welding device manufactured by Kobayashi Kogyo Co., Ltd. (no model number) was used for the pre-processing and joining processes. This hot plate welding device has an upper base and a lower base (not shown) that are positioned opposite each other and can move vertically to change the distance between them. Using the reference numerals shown in Figures 3-4 to describe the arrangement, a base material installation jig 50 is fixed to the lower base. A restraining jig 60 for restraining the molded body 20 is fixed to the upper base. By moving the upper base, with the molded body 20 restrained below by the restraining jig 60, and the lower base, with the base material 10 placed on the base material installation jig 50, closer together, the molded body 20 and the base material 10 can be brought into contact and joined. Furthermore, this hot plate welding device has a molded body heating jig 30 that can move horizontally to change the position in which the molded body 20, restrained on the upper base via the restraining jig 60, contacts and separates from the molded body joining surface 21. Furthermore, this hot plate welding apparatus has a base material heating jig 40 that can move horizontally to change the position in which it contacts and separates from the joining surface 11 of the base material 10, which is installed on a lower base via a base material installation jig 50. The molded body heating jig 30, the base material heating jig 40, and the base material installation jig 50 are in the shape of thick aluminum plates and have built-in electric heaters, and can be heated to a desired set temperature by conductive heating from the electric heaters. In this embodiment, the hot plate welding apparatus can heat the molded body 20 by contact-type heat transfer heating by the molded body heating jig 30. In this embodiment, the hot plate welding apparatus can heat the base material 10 by heat transfer heating by the base material heating jig 40 and the base material installation jig 50.

[0058] First, a preheating process was carried out using the laser-treated aluminum substrate 110 (hereinafter referred to as "aluminum substrate") and the resin molded body 120 (hereinafter referred to as "resin molded body") prepared as described above. The aluminum substrate 110 was placed on a substrate mounting jig 50 fixed to the lower base of the hot plate welding apparatus. The temperature of the substrate mounting jig 50 was set to 315°C. The resin molded body 120 was restrained with a restraining jig 60.

[0059] Next, the heating fixtures, the molded body heating fixture 30 and the base material heating fixture 40, were moved between the aluminum base material 110 and the resin molded body 120, which were positioned opposite each other. Then, with the joint surface 111 of the base material facing the base material heating fixture 40, the lower base was moved upward along with the base material installation fixture 50 and the base material 110, so that the joint surface 111 of the aluminum base material 110 came into contact with the base material heating fixture 40 and was heated. The temperature of the base material heating fixture 40 was set to 355°C. Furthermore, with the joint surface 125 of the molded body 120 facing the molded body heating fixture 30, the upper base was moved downward along with the restraining fixture 60 and the resin molded body 120, so that the joint surface 125 of the resin molded body came into contact with the molded body heating fixture 30 and was heated. The temperature of the molded body heating fixture 30 was set to 215°C. The contact heating of the aluminum substrate 110 by the substrate heating jig 40 and the contact heating of the resin molded body 120 by the molded body heating jig 30 were started at the same time. In both cases, the heating time by contact with the heating jigs 30 and 40 was 10 seconds. After that, the molded body heating jig 30 and the substrate heating jig 40 were moved to a position away from the substrate 110 and the molded body 120, and the temperatures of the joint surfaces 111 and 125 of the aluminum substrate 110 and the resin molded body 120 were measured using a temperature sensor. The joint surface 111 of the aluminum substrate 110 was 345°C, and the joint surface 125 of the resin molded body 120 was 210°C. In this embodiment, a Keyence digital radiation temperature sensor FT-H20 was used as the temperature sensor for measuring the surface temperature of the substrate 110 and the molded body 120. In Tables 1 and 2 described below, the temperatures of these bonding surfaces are expressed as "Al temperature before bonding" and "Resin temperature before bonding," respectively.

[0060] Immediately after measuring the temperature of the joining surface, the lower base was moved upward along with the base material installation jig 50 and base material 110, and the upper base was moved downward along with the restraining jig 60 and molded body 120, thereby bringing the joining surface 111 of the aluminum base material 110 and the joining surface 125 of the resin molded body 120 into contact. Furthermore, a pressure of 3000N (6.58MPa) was applied to pressurize the joining. At this time, the inner 3mm from the outermost circumference of the aluminum base material 110 was joined to the resin molded body 120. After contact, air cooling was started after 10 seconds, and after 40 seconds of pressurization, the pressurization was released and the joined body was removed. The pressurization time was 50 seconds. At this time, the temperature of the aluminum base material 110 measured using the above temperature sensor was 255℃, which is shown as the "removal temperature". The cycle time for producing the joined body was a good 60 seconds. Note that the cycle time is the time from the start of heating in the preheating process to the start of pressurization in the joining process. In other words, the cycle time is the sum of the preheating process time and the pressurization time. The resulting joints underwent airtightness testing and resin appearance verification as described below. Furthermore, jig contamination (adhesion of resin to the jig) was confirmed. The results are shown in Table 1.

[0061] [2. Evaluation Method] <Measurement of resin melting point> The resin melting point temperature was measured using a differential scanning calorimeter DSC7020 manufactured by Hitachi High-Tech Science Corporation. The measurement conditions were a heating rate of 5°C / min, and the peak of the endothermic peak was defined as the resin melting point temperature. In cases where two or more endothermic peaks were observed, indicating the presence of a mixture of two or more components, the temperature of the higher endothermic peak was defined as the resin melting point temperature. The PPS resin used was Z-230 manufactured by DIC Corporation. The endothermic peak temperature was 285°C, which was defined as the resin melting point. The PA resin used was Asahi Kasei's 53G33, and the endothermic peaks were at 210°C and 254°C. In other words, for the two-component 53G33, the higher side was 254°C, so this was taken as the resin melting point.

[0062] <Airtightness inspection> A hose manufactured by Kohshin Rubber (dimensions: inner diameter 15.9 mm, outer diameter 25 mm) was inserted into one pipe section 126 of the resin molded body of the joint. For the other pipe section, a hose sealed with a hose nipple on one end was inserted. This joint was placed in a water tank, and air was blown in from the unsealed hose end using a compressor, applying an air pressure of 0.1 MPa inside the joint. It was confirmed that there was no air leakage from the joint interface of the joint to determine whether the airtightness was good. The appearance of the resin was also checked for any clear deformation. "OK" was used to indicate that there were no air leaks and the airtightness was good. "NG" was used to indicate that there were air leaks and the airtightness was not good, or that the resin was deformed and had a poor appearance.

[0063] <Checking for jig contamination> The molded body heating jigs, substrate heating jigs, substrate placement jigs, and molded body restraint jigs were checked for resin adhesion after use. If no resin adhesion was found on any of the jigs, it was marked as "none." If resin adhesion was found on any of the jigs, that jig was marked and judged to be defective.

[0064] [Examples 2-6] Except for changing the temperatures of the molded body heating jig, substrate heating jig, and substrate placement jig of the hot plate welding apparatus to the conditions shown in Table 1, joints of Examples 2 to 6 were obtained in the same manner as in Example 1. Evaluations were performed in the same manner as in Example 1. The airtightness of all obtained joints was good. It was also confirmed that there was no clear deformation of the resin surface and no contamination of the jigs. The results are shown in Table 1.

[0065] [Comparative Examples 1-7] The joints of Comparative Examples 1 to 7 were obtained in the same manner as in Example 1, except that the temperatures of the molded body heating jig, substrate heating jig, and substrate placement jig of the hot plate welding apparatus, and the pressurization time were changed to the conditions shown in Table 1. Evaluations were performed in the same manner as in Example 1. Air leaks were confirmed in the joints obtained in Comparative Examples 1-3 and 6 through airtightness testing. In Comparative Example 4, although the airtightness of the obtained joint was good, it was judged to be defective due to jig contamination because a portion of the molten resin molded body was adhering to the molded body heating jig. In Comparative Example 5, air leaks were confirmed in airtightness testing. Furthermore, deformation of the resin surface, and a portion of the resin molded body adhering to the metal substrate mounting jig and the resin molded body restraining jig were judged to be defective due to jig contamination. In Comparative Example 7, although the airtightness was good, it was judged to be defective (NG) because the cycle time was 110 seconds, which was longer than the cycle time of the example. The results are shown in Table 1.

[0066] [Examples 7-13] Except for changing the resin molded body to PA 53G33 manufactured by Asahi Kasei Corporation, changing the temperatures of the molded body heating jig, substrate heating jig, and substrate setting jig of the hot plate welding apparatus to the conditions shown in Table 2, and changing the pressurization time to 70 seconds, the jointed bodies of Examples 7 to 13 were obtained in the same manner as in Example 1. The airtightness of all the resulting joints was good. Furthermore, it was confirmed that there was no significant deformation of the resin surface and no contamination of the jigs. The results are shown in Table 2.

[0067] [Comparative Examples 8-14] Joints of Comparative Examples 8 to 14 were obtained in the same manner as in Example 7, except that the temperature of the molded body heating jig, base material heating jig, and base material placement jig of the hot plate welding apparatus and the pressurization time were changed to the conditions shown in Table 2. Air leaks were confirmed in the joints obtained in Comparative Examples 8 to 10 and 13 by airtightness testing. In Comparative Example 11, the airtightness of the obtained joint was good, but a portion of the molten resin molded body was attached to the molded body heating jig of the resin molded body, so it was judged to be defective due to jig contamination. In Comparative Example 12, air leaks were confirmed by airtightness testing. Furthermore, deformation of the resin appearance and a portion of the resin molded body being attached to the molded body heating jig and the molded body restraining jig of the resin molded body were judged to be defective due to jig contamination. In Comparative Example 14, the airtightness was good, but the cycle time was 135 seconds, which was longer than the cycle time of the example, so it was judged to be defective (NG). The results are shown in Table 2.

[0068] [Table 1]

[0069] [Table 2]

[0070] [Consideration] As can be seen from the results described above, in the method for manufacturing a joined body of the present invention according to Examples 1 to 13, in the preheating step, the substrate joining surface and the molded body joining surface are heated in a non-contact state. At this time, the substrate joining surface is heated to a temperature range of -5°C or higher and +100°C or lower, with a lower limit near the resin melting point and an upper limit of 100°C higher than the resin melting point. The molded body joining surface is heated to a temperature range of -80°C or higher and +30°C or lower, with the resin melting point as the center and the lower end. As a result, according to Examples 1 to 13, even when heating the molded body by a contact method in which the molded body heating jig and the molded body joining surface are in contact, the molded body does not melt and resin does not adhere to the jig and contaminate the jig, and the bonding can be performed while maintaining the airtightness of the interface between the substrate and the molded body formed by the bonding. Furthermore, in Examples 1 to 13, the heating temperature in the preheating step was set as described above, and the bonding method involved directly bonding the substrate and the molded body without heating. As a result, in Examples 1 to 13, the temperature of the substrate after bonding (removal temperature) after a predetermined time had elapsed since the start of bonding could be rapidly reduced to the point where the resin of the molded body had solidified when the pressurized state was released. In this way, Examples 1 to 13 were methods that made it easy to reduce the cycle time by reducing the cooling time required for the substrate temperature to decrease.

[0071] In contrast, in Comparative Examples 1-3 and 8-10, where the temperature of either the substrate bonding surface or the molded body bonding surface was below the lower limit of the aforementioned temperature range, although jig contamination did not occur, it was not possible to bond the substrate and the molded body resin while maintaining airtightness at the interface. From this, it can be inferred that when the heating temperature of the substrate bonding surface or the molded body bonding surface is too low, even if the molded body receives heat from the substrate during bonding, it was not possible to melt enough resin to fill the rough surface structure of the substrate.

[0072] Furthermore, in Comparative Examples 4 and 11, where the temperature of the molded body joining surface exceeded the upper limit within the aforementioned temperature range, joining was possible while maintaining airtightness at the interface between the substrate and the molded body, but contamination of the molded body heating jig occurred. This is thought to be because the molded body melted due to the high heating temperature of the molded body in the preheating process, and some of the resin adhered to the molded body heating jig. From this, it can be inferred that when the heating temperature of the molded body joining surface is too high, excessive heating is being performed for the purpose of melting the molded body by receiving heat from the substrate during joining. In this case, although it is a method that can easily improve joining quality, it is inferred that it is a method with low production efficiency because it does not reduce the cycle time due to the need for cleaning and maintenance of the jig.

[0073] Furthermore, in Comparative Examples 5 and 12, where the temperature of the substrate bonding surface exceeded the upper limit within the aforementioned temperature range, it was not possible to bond the substrate and the molded body while maintaining airtightness at the interface. In addition, deformation of the molded body occurred, and contamination of the substrate mounting jig and the molded body restraining jig occurred. This is thought to be due to the high heating temperature of the substrate during the preheating process, which caused the molded body in contact with the substrate to melt, and the molten resin to flow and adhere to the substrate mounting jig and the molded body restraining jig. From this, it can be inferred that when the heating temperature of the substrate bonding surface is too high, excessive heat from the substrate is applied to the molded body during bonding. In this case, it can be inferred that this is a method with low bonding quality and that it is not possible to reduce the cooling time of the substrate or the cycle time.

[0074] Furthermore, in Comparative Examples 6 and 13, where the temperature of the substrate bonding surface exceeded the upper limit within the aforementioned temperature range, when the pressurization time for Comparative Example 6 was set to 50 seconds and for Comparative Example 13 to 70 seconds, it was not possible to bond the substrate and the molded body while maintaining airtightness at the interface. From this, it can be inferred that when the heating temperature of the substrate bonding surface is too high, excessive heat from the substrate is supplied to the molded body during bonding. In this case, it can be inferred that the removal temperature when the pressurization is released and the bonded body is removed has not decreased sufficiently, and as a result of removing the molded body before the resin contained in it has solidified, the bonding quality deteriorates.

[0075] Furthermore, in Comparative Examples 7 and 14, where the temperature of the substrate bonding surface exceeded the upper limit within the aforementioned temperature range, extending the pressurizing time to 100 seconds and 120 seconds resulted in removal temperatures of 230°C and 178°C, respectively, allowing for bonding while maintaining airtightness at the interface between the substrate and the molded body. In this case, it is presumed that extending the pressurizing time lowered the removal temperature, causing the resin to solidify upon removal. However, in this case, extending the pressurizing time is necessary, resulting in relatively long cycle times of 110 seconds and 135 seconds, respectively, and it is presumed that this method does not allow for a reduction in cycle time. [Explanation of Symbols]

[0076] 1...Zygote 10...Base material 11…Base material bonding surface 12…The side opposite to the substrate bonding surface 20…Molded body 21... Molded object joint surface 30… Heating jig for molded body 40…Substrate heating jig 50…Substrate installation jig 60… Restraint fixtures 110…Aluminum base material 111...Bonding surface of aluminum substrate 112...Bonding surface and opposite surface of the aluminum substrate 120…Resin molded body 121...Cavity part 122...Top part 123…Side part 124…Opening 125...Opening end surface 126...Pipe section

Claims

1. A method for manufacturing a jointed body in which a substrate containing metal or ceramics and a molded body containing thermoplastic resin are directly joined, The substrate has a substrate bonding surface that is joined to the molded body, The molded body has a molded body joining surface that is joined to the substrate, A surface roughening step to form a rough surface structure on the substrate bonding surface, A preheating step for heating the substrate bonding surface and the molded body bonding surface, The invention comprises a joining step of joining the substrate and the molded body by placing the heated substrate joining surface and the molded body joining surface facing each other, and applying pressure while the substrate joining surface and the molded body joining surface are in contact, In the preheating step, the substrate bonding surface and the molded body bonding surface are heated in a non-contact state with each other. In the preheating step, the joint surface of the molded body is heated by contact heating from the surface side. In the preheating step, the substrate bonding surface is heated to a range of 5°C or higher and 100°C or lower, which is the melting point of the thermoplastic resin, and the molded body bonding surface is heated to a range of 80°C or higher and 30°C or lower. In the joining process, the substrate and the molded body are joined without heating. A method for manufacturing a jointed body, characterized by the above.

2. The method for manufacturing a bonded body according to claim 1, wherein in the preheating step, the heating temperature of the substrate bonding surface is higher than the heating temperature of the molded body bonding surface.

3. The method for manufacturing a bonded body according to claim 2, wherein in the preheating step, the heating temperature of the bonded surface of the substrate is in the range of above the resin melting point temperature and above the resin melting point temperature + 50°C, and the heating temperature of the bonded surface of the molded body is in the range of above the resin melting point temperature and above the resin melting point temperature + 20°C.

4. The method for manufacturing a joined body according to claim 1, wherein in the preheating step, the substrate and the molded body are heated with the substrate joining surface and the molded body joining surface facing each other.

5. The method for manufacturing a joined body according to claim 1, wherein the joining step is performed within 30 seconds after the preheating step.

6. The method for manufacturing a joined body according to claim 1, wherein the heating method for heating the molded body in the preheating step is conductive heating.

7. The method for manufacturing a bonded body according to claim 1, wherein the heating method for heating the substrate in the preheating step is at least one selected from the group consisting of conduction heating, radiation heating, convection heating, high-frequency dielectric heating, microwave heating, induction heating, and laser heating.

8. The method for manufacturing a bonded body according to claim 1, wherein the molded body includes a filler.

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