JP2011240496A - Joining method using laser beam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To join members made of materials which can not easily be welded to each other together to have sufficient joining strength by a joining method using a laser beam.SOLUTION: A primer layer 4 which improves fusion force with an intermediate material 5 is formed in a first member 2. After that, the intermediate material 5 made of a polymer alloy containing a first resin having fusibility with the resin of the primer layer and a second resin having fusibility with a second member 3 is arranged between the primer layer 4 and the second member 3. Next, while the first member 2, the polymer alloy, and the second member 3 are placed one upon another, the intermediate material 5 is heated by being irradiated with laser beam, the first resin in the polymer alloy and the resin of the primer layer 4 are fused together, and the second resin in the polymer alloy and the second member 3 are fused together.

Description

  The present invention relates to a joining method for joining a first member and a second member using a laser beam.

  Conventionally, for example, as a method of joining a first member and a second member made of a resin material, a joining method of irradiating laser light has been widely used (see, for example, Patent Documents 1 to 3). In Patent Documents 1 to 3, a laser light absorber made of a toner or a paint that absorbs laser light is interposed between the first member and the second member, and the laser light is absorbed by the laser light absorber. The joining portion of the member and the second member is heated and melted, thereby joining the first and second members.

JP 2003-181931 A JP 2004-1071 A JP 2005-238462 A

  By the way, the above-described joining method using laser light has high productivity, and it is desired to expand its application range. However, although the joining methods of Patent Documents 1 to 3 can be applied when the first member and the second member are easily fused, the first member and the second member are different in material type. Thus, in the case of a material that is difficult to weld, even if the methods of Patent Documents 1 to 3 are used, it is difficult to ensure a sufficient bonding strength, and as a result, the application range of a bonding method using laser light is limited. It will be narrow.

  The present invention has been made in view of the above points, and the object of the present invention is to provide members having a sufficient bonding strength to each other by using a laser beam bonding method. It is to be able to join.

  In order to achieve the above-mentioned object, in the present invention, a primer layer is formed on the first member, and a polymer alloy having a fusion property with the resin of the primer layer and a fusion property with the second member. Was disposed between the first member and the second member, and then the laser beam was irradiated to join the first member and the second member via the polymer alloy and the primer layer.

  A first invention is a bonding method in which a first member formed by molding different materials and a second member are bonded by irradiating a laser beam in a state where an intermediate material is disposed between the two members. A primer layer for improving the fusion force with the intermediate material is formed on the side of the one member that joins the second member, and then a first resin having a fusion property with the resin contained in the primer layer. And the intermediate material made of a polymer alloy containing a second resin having a fusibility with the second member is disposed between the primer layer and the second member, and then the first member, In a state where the intermediate material and the second member are stacked, the intermediate material is heated by irradiating a laser beam, and the first resin in the polymer alloy and the resin of the primer layer are fused, and the polymer alloy Second resin inside and the above It is characterized in that fusing the member.

  According to this configuration, the first resin in the polymer alloy of the intermediate material is fused to the resin of the primer layer formed on the first member, and the second resin in the polymer alloy is fused to the second member. . As a result, when the first member and the second member are made of different resins and are not easily fused, the first member and the second member are fused via the polymer alloy and the primer layer. The bonding strength between the first member and the second member is sufficiently obtained.

  The second invention is characterized in that, in the first invention, the fusing force between the polymer alloy and the second member is set stronger than the fusing force between the polymer alloy and the first member.

  That is, since the primer layer formed on the first member has a strong binding force with the first member, peeling of the primer layer is avoided. Further, the fusion force between the resin of the primer layer and the first resin in the polymer alloy of the intermediate material is strong.

  In addition, since the fusion force between the second resin and the second member in the polymer alloy of the intermediate material is stronger than the fusion force between the first resin and the first member, the fusion force between the intermediate material and the second member is sufficient. Secured. Thereby, a 1st member and a 2nd member will join firmly via a primer layer and an intermediate material.

  According to a third invention, in the first or second invention, the intermediate material has an absorbent that absorbs laser light.

  According to this configuration, the irradiated laser light is absorbed by the laser light absorbent of the intermediate material, so that the polymer alloy is reliably heated even when using low-power laser light.

  According to a fourth invention, in any one of the first to third inventions, the primer layer has an absorbent that absorbs laser light.

  According to this configuration, the primer layer adjacent to the intermediate material is heated by the laser light. And the heat | fever of a primer layer is transmitted to an intermediate material, and an intermediate material is heated.

  According to the first aspect of the present invention, a primer layer having a fusibility with the first member is formed, the first resin having a fusibility with the resin of the primer layer formed on the first member, and the second member. An intermediate material made of a polymer alloy containing a second resin having fusibility is disposed between the primer layer and the second member, and the intermediate material is heated by irradiation with laser light. As a result, when the first member and the second member are made of a material that is difficult to fuse, the first member and the second member can be bonded with sufficient bonding strength. The scope of the method can be expanded.

  According to the second invention, since the fusion force between the polymer alloy of the intermediate material and the second member is set stronger than the fusion force between the polymer alloy and the first member, the composition of the polymer alloy can be designed widely. The bonding strength between the member and the second member can be further increased.

  According to the third invention, since the intermediate material has the laser light absorber, the polymer alloy of the intermediate material can be reliably heated even when using low-power laser light, and the first resin in the polymer alloy The resin of the primer layer can be reliably fused, and the second resin and the second member in the polymer alloy can be reliably fused. Thereby, the joint strength between the first member and the second member can be further increased.

  According to the fourth invention, since the primer layer has the laser light absorber, the heat of the primer layer heated by the laser light can be transmitted to the intermediate material to reliably heat the polymer alloy of the intermediate material. Thereby, a melt | fusion property can be improved further.

It is sectional drawing of the joining goods obtained by the joining method using the laser beam concerning embodiment. It is sectional drawing which shows the state before joining each member.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

  FIG. 1 shows a bonded product 1 obtained by a bonding method using laser light according to an embodiment of the present invention. The joined product 1 is obtained by integrating a first member 2 and a second member 3 with an intermediate material 5 interposed therebetween. The first member 2 and the second member 3 are made of different types of resins. Even if these resins are melted and fused with laser light, it is impossible to obtain bonding strength that can withstand practical use, and conventional bonding methods using laser light cannot be applied. It is.

  The first member 2 is a plate-like member, and may be made of a material that does not allow laser light to pass therethrough or may be made of a material that has laser light permeability that allows laser light to pass through. Good. Here, the laser beam impermeability is a laser beam absorptivity that absorbs the laser beam, and refers to the property of absorbing the remainder even if the laser beam as a heating source is partially transmitted and / or reflected, Includes those that absorb all of the laser light. As a material having such properties, for example, there is a material obtained by mixing a pigment or a dye with a resin. As the laser light non-light-transmitting property, for example, the transmittance of laser light having a wavelength of 940 nm is preferably less than 15%. In the present embodiment, the first member 2 is made of polypropylene (PP).

  The 2nd member 3 is a plate-shaped member comprised with the material which has a laser beam permeability which lets a laser beam pass. Laser light transmission means that the laser beam as a heating source is transmitted with almost no reflection or absorption, or the remaining laser beam is transmitted without melting even if the laser beam is partially transmitted and / or reflected. This includes the properties that can be transmitted, including those that transmit all of the laser light. The second member 3 is made of acrylonitrile-butadiene-styrene resin (ABS).

  For the resin constituting the first member 2 and the second member 3, for example, a thermal stabilizer, an antioxidant, an ultraviolet stabilizer, a conductive agent, a nucleating agent, a release agent, a flame retardant, an antistatic agent, It is also possible to mix at least one selected from the group consisting of processing preparations, colored and functional pigments or dyes, crosslinking agents, plasticizers and vulcanizing agents. When a colored pigment or dye is mixed with the resin constituting the second member 3, the second member 3 is not colorless and transparent, but may be of an amount that can ensure a predetermined laser beam transparency.

  Although the thickness of the 1st member 2 and the 2nd member 3 is not specifically limited, For example, it is about several mm. The first member 2 may be made of a laser light transmissive member.

  A primer layer 4 containing a resin for improving the fusion force with the intermediate member 5 is formed on the joint surface of the first member 2 with the second member 3.

  The properties required for the primer layer 4 include good compatibility with the intermediate material 5 and the first member 2. Further, the primer layer 4 may be reactive with at least one of the intermediate member 5 and the first member 2. Further, the primer layer 4 may or may not have a laser light absorbability for absorbing the laser light L.

  Examples of the resin contained in the primer layer 4 include a thermoplastic resin. Specifically, polyethylene (HDPE, LDPE, LLDPE, VLDPE, ULDPE, UHDPE, Polyethylene), polypropylene (PP Co-Polymer, PP Homo-Polymer, PP Ter-Polymer), polyvinyl chloride (PVC), polystyrene (PS), polymethyl methacrylate (PMMA), acrylonitrile-butadiene-styrene resin (ABS), styrene acrylonitrile resin (SAN), K-resin , SBS resin (SBS block co-polymer), PVDC resin, EVA resin, acrylic resin, butyral resin, silicone resin, polyamide (PA, PA6, PA66, PA46, PA610, PA612, PA6 / 66, PA6 / 12, PA6T, PA12, PA1212, PAMXD6), ethylene tetrafluoroethylene copolymer, liquid crystal polymer, polybutylene terephthalate, polyether ether ketone, polyether ketone, polyether ketone ketone Polyethylene naphthalene, polyethylene terephthalate, polyimide, polyacetal, polyamideimide, polyphenylene ether, polyphenylene oxide, polycarbonate, polyphenylene sulfide, polysulfone, polythioethylsulfone, polytetrafluoroethylene, polyethersulfone, and polyetherimide.

  In addition, it may be a modified resin in which polar functional groups are chemically bonded. Specifically, an acrylic acid-modified olefin resin, a maleic acid-modified olefin resin, a chloride-modified olefin resin (CPP, CPE), a silane-modified olefin resin. , Ionomer resin, nylon-modified olefin resin, epoxy-modified resin, ethylene vinyl alcohol resin (EVOH), ethylene vinyl acetate resin, hot melt adhesive resin, and the like, which are mixtures or combinations of these and the above thermoplastic resins. May be.

  The resin contained in the primer layer 4 may be a thermoplastic elastomer, and specifically, a styrene elastomer, an olefin elastomer, a polyester elastomer, a vinyl chloride elastomer, a polyamide elastomer, a polybutadiene elastomer, an isoprene based resin. Examples include elastomers, ion clusters and amorphous PE elastomers, chlorinated PE and amorphous PE elastomers, fluorine elastomers, polyurethane elastomers, and acrylic elastomers.

  The resin contained in the primer layer 4 may be a thermosetting resin, and specifically, phenolic resin, urea resin, sulfoamide resin, cyanate resin, isocyanate resin, melamine resin, guanamine. Resin, aniline resin, epoxy resin, urea resin, polyimide resin, maleimide resin, urethane resin, polyester resin, allyl resin, unsaturated polyester resin, benzoxazine resin, xylene resin, ketone resin, furan Examples thereof include resins, dicyclopentadiene resins, silicon resins, benzocyclobutene resins, episulfide resins, ene-thiol resins, polyazotimene resins, polyvinyl benzyl ether resins, and curable acrylic resins. Further, it may be a rubber having thermosetting properties, specifically, natural rubber, isoprene rubber, ethylene propylene diene rubber, ethylene propylene rubber, styrene butadiene rubber, butadiene rubber, chlorosulfonated polyethylene rubber, isoprene rubber, Examples include chloroprene rubber, acrylic rubber, epichlorohydrin rubber, urethane rubber, nitrile rubber, hydrogenated nitrile rubber, fluorine rubber, and silicon rubber. Alternatively, the primer layer 4 may be composed of a composite resin or copolymer made by mixing the above resins.

  In addition, the primer layer 4 may be provided with adhesiveness by mixing an adhesive component. Typical examples of the adhesive component include rubber, acrylic, urethane, and silicon.

  Thermoplastic elastomers are also commonly used as a base for rubber-based pressure-sensitive adhesives, and are not particularly limited. However, thermoplastic elastomers can be made into pressure-sensitive adhesives by blending tackifiers, oils, liquid oligomers, crosslinking agents, and the like. The liquid oligomer can be selected from acrylic, styrene, rubbers such as polyisoprene and butadiene, polyesters, and other high-viscosity polymers having a molecular weight of several hundred to several thousand.

  The primer layer 4 may be mixed with a tackifier. Specifically, for example, a rosin tackifier resin, a terpene tackifier resin, a hydrocarbon tackifier resin, a coumarone resin, a coumarone indene resin, etc. Is mentioned. Oil may be selected from paraffinic, naphthenic, and aroma types, which are broadly classified.

  In addition to the primer layer 4, for example, a silane coupling agent, a titanate coupling agent, a silicate compound, a urethane compound, a polyvalent carboxylic acid, a polyester polyol / polyether polyol / polycarbonate polyol or the like alone or in combination of two or more. Combined polyols, isocyanates or polyisocyanates alone or in combination of two or more, fluorine resins, silicon resins, cyano compounds, nitrile compounds, carbodiimide compounds and resins, ester compounds, acid anhydrides, adamantane compounds , Isocyanurate compounds and the like may be mixed.

  In addition, for the purpose of improving practical properties such as leveling properties and bonding strength of the primer layer 4, a reinforcing material or a filler can be added to the above-described thermoplastic resin or thermosetting resin. Reinforcing materials and fillers include, for example, potassium titanate, aluminum borate, magnesium sulfate, calcium carbonate and their whiskers, glass fibers, carbon fibers, metal fibers, aramid fibers, asbestos, silicon carbide, ceramics, barium sulfate, Calcium sulfate, kaolin, clay, silica, pyrophyllite, bentonite, sericite, zeolite, montmorillonite, mica, mica, nepheline cinteite, talc, talbalsite, wollastonite, PMF, ferrite, calcium silicate, calcium carbonate , Magnesium carbonate, dolomite, silica, zinc oxide, titanium oxide, magnesium oxide, iron oxide, molybdenum disulfide, graphite, gypsum, glass beads, glass powder, glass balloon, quartz, quartz glass and the like.

  Moreover, the filler used may be hollow. In addition, two or more kinds of the above fillers can be used in combination, and if necessary, they can be used after pretreatment with a coupling agent such as silane or titanium. Organic and inorganic coloring pigments and dyes can be added to the primer layer 4, and the amount of these, the reinforcing material, and the filler is such that the primer layer 4 can ensure a predetermined laser light absorbability. Can be adjusted as appropriate.

  In addition to the primer layer 4, various additives may be blended as necessary. For example, peptizers, scorch inhibitors, plasticizers, flame retardants, antioxidants, heat stabilizers, light stabilizers, UV absorbers, lubricants, pigments, crosslinking agents, crosslinking aids, vulcanizing agents, vulcanization Common rubber and plastic compounding chemicals such as accelerators and anti-curing agents are listed.

  In addition to the resin, the primer layer 4 is mixed with a laser light absorber that absorbs laser light. Examples of the laser light absorber include carbon black, but are not limited thereto.

  The intermediate material 5 is made of a polymer alloy including a first resin having a fusion property with the resin of the primer layer 4 and a second resin having a fusion property with the resin constituting the second member 3. . The intermediate material 5 is basically in the form of a sheet, but the shape is not limited to this, and any shape that can effectively join the first member 2 and the second member 3 may be used. In addition, the intermediate material 5 has thermoplasticity that melts when heated by laser light irradiation. The thickness of the intermediate material 5 is preferably 10 μm or more and 2000 μm or less, but is not limited to this range. If the intermediate material 5 is very thin, it will have a film shape, whereas if it is thick, it will have a plate shape. The polymer alloy has elasticity, and the elastic modulus is set to 0.01 or more and 500 MPa or less. The value of the elastic modulus can be arbitrarily set depending on the type of the first resin and the second resin, the type and amount of the elastomer mixed in the polymer alloy, and the like.

  The first resin in the polymer alloy of the intermediate material 5 is a resin having good compatibility with the resin contained in the primer layer 4, and examples thereof include styrene-ethylene-butylene-styrene rubber (SEBS). It is not limited to. The difference in SP value (solubility parameter) between the first resin in the polymer alloy of the intermediate material 5 and the resin contained in the primer layer 4 is preferably 1.0 or less. The SP value can be calculated by, for example, the Fedors method.

  The second resin in the polymer alloy is a resin having a good compatibility with the resin constituting the second member 3, and examples thereof include polymethyl methacrylate resin (PMMA), but are not limited thereto. . The difference in SP value between the second resin in the polymer alloy and the resin constituting the second member 3 is preferably 1.0 or less.

  The fusing force between the polymer alloy and the second member 3 is set to be stronger than the fusing force between the polymer alloy and the first member 2.

  The intermediate material 5 is mixed with a laser light absorbent that absorbs laser light. Examples of the laser light absorber include carbon black, but are not limited thereto. As the laser beam impermeability of the intermediate material 5, for example, it is preferable that the absorptance of the laser beam having a wavelength of 940 nm is 15% or more.

  The intermediate material 5 may be mixed with a heat conductive filler or may not be mixed.

  Next, the manufacturing procedure of the joined product 1 will be described. First, a coating material for forming the primer layer 4 is applied to the joint surface of the first member 2 with the second member 3. When this paint is dried, the primer layer 4 is formed. The bonding force between the primer layer 4 and the first member 2 is sufficiently strong.

  There are various methods for forming the primer layer 4, but the method is not particularly limited. When using a solution-type primer paint, the application method is, for example, a spatula, a brush, a stick, a syringe, an oil jug as a simple applicator, a hand roller, a caulking gun, a sealant gun, a flow gun, or a flow brush. Various types of coaters such as spray guns, flow coaters, foil coaters, roll coaters, knife coaters, brush coaters, immersion coaters and curtain coaters can be used.

  Further, the primer layer 4 is not limited to being formed of a solution type, and includes, for example, a solid type coated by a hot melt method. In this case, a nozzle type and a wheel type applicator In addition, hot melt coaters such as roll coaters, curtain flow coaters, and special coaters can be used.

  Further, when the first member 2 is molded, a solid type primer may be molded and integrated with the first member 2. That is, for example, when the first member 2 is extrusion-molded or injection-molded, a solid-type primer is molded on the joining side of the first member 2 with the intermediate material 5 by using a two-color molding method. Thereby, the primer layer 4 is obtained.

  Alternatively, the primer layer 4 may be formed by a lamination technique such as wet, dry, or heating using a primer resin previously formed into a film shape.

  After forming the primer layer 4, the intermediate member 5 is disposed between the first member 2 and the second member 3, and the first member 2, the intermediate member 5, and the second member 3 are stacked. At this time, the first member 2 and the second member 3 may be clamped in the thickness direction using a jig (not shown).

  Then, as shown in FIG. 1, the laser beam L is irradiated toward the intermediate member 5 from the second member 3 side. The type of the laser beam L can be appropriately selected according to the material, thickness, shape, laser beam transmission degree, and the like of the objects to be joined (first member 2, intermediate member 5 and second member 3). As a device for irradiating the laser beam L, a known device can be used.

  As the type of the laser beam L, for example, a gas laser, for example, a solid laser (Nd: YAG excitation, semiconductor laser excitation, etc.), a semiconductor laser, a tunable diode laser, a titanium sapphire laser (Nd: YAG excitation), etc. are used. The type of the laser beam L is not limited. Of these laser beams, a laser beam having an oscillation wavelength of 800 to 1600 nm, preferably 800 to 1100 nm, which is longer than visible light is usually used. Further, the laser beam L may be composed of one wavelength, or may have two or more wavelengths. As the beam shape of the laser light L, a circle, an ellipse, a line, a donut shape, or the like can be selected as necessary.

  The laser beam L may be irradiated from a vertical direction or an oblique direction with respect to the intermediate portion in the thickness direction of the bonding target. The laser beam L may be emitted from a plurality of directions as well as one direction. The laser beam L may be irradiated while moving the object to be joined, or spot irradiation, pulse irradiation, line irradiation, and collective irradiation for the shape to be fused may be performed simultaneously by a single laser beam or a plurality of laser beams.

  Also, if the output of the laser beam L is too low, it becomes difficult to melt the joint parts of the resin, and if the output is too high, the resin evaporates or deteriorates and the strength decreases. The output of the laser beam L as conditions, the scanning speed, the focal position, the clamping pressure by the clamping jig to the object to be joined, etc. are adjusted as appropriate.

  The irradiated laser beam L passes through the second member 3 and reaches the intermediate material 5. The laser beam L that has reached the intermediate material 5 is absorbed by the laser absorbent of the intermediate material 5, thereby heating the intermediate material 5.

  When the intermediate material 5 is heated to the melting temperature, it starts to melt. The heat of the intermediate material 5 is transmitted to the primer layer 4 and the primer layer 4 is also melted. Furthermore, the heat of the intermediate member 5 is also transmitted to the second member 3 and the joined portion of the second member 3 is melted.

  When the intermediate material 5 and the primer layer 4 are melted, the first resin of the polymer alloy and the resin of the primer layer 4 are mixed. Further, when the joining portion of the intermediate member 5 and the second member 3 is melted, the second resin of the polymer alloy and the resin of the second member 3 are mixed.

  Part of the laser beam L (a few percent of the irradiated laser beam L) may pass through the intermediate material 5. The slight laser light L that has passed through the intermediate material 5 reaches the primer layer 4. Since the laser light absorbent is mixed in the primer layer 4, the laser light L transmitted through the intermediate material 5 is absorbed by the laser absorbent in the primer layer 4 and the primer layer 4 is heated. Since the heat of the primer layer 4 is transmitted to the intermediate material 5 and the intermediate material 5 is heated, the laser beam L can be used effectively.

  Further, since the intermediate material 5 is provided with a laser absorptivity, the intermediate material 5 can be reliably heated and melted even when a low-power laser beam is used. Therefore, the first member 2 and the second member 3 can be prevented from being damaged (burned or deformed) by heat.

  After the irradiation with the laser beam L is completed, the intermediate material 5 is cooled and solidified. When the intermediate material 5 is solidified, the first resin in the polymer alloy of the intermediate material 5 is fused with the resin of the primer layer 4, and the second resin in the polymer alloy is fused with the second member 3. It becomes. Thereby, the 1st member 2 and the 2nd member 3 are joined, and the joined article 1 is obtained.

  The first resin in the polymer alloy of the intermediate material 5 has good compatibility with the resin of the primer layer 4, and the primer layer 4 has a high binding force with the first member 2. The bonding strength with the member 2 is high. Moreover, since the second resin in the polymer alloy of the intermediate material 5 has good compatibility with the resin constituting the second member 3, the bonding strength between the intermediate material 5 and the second member 3 is high.

  Furthermore, the primer layer 4 formed on the first member 2 has a strong bonding force with the first member 2 as described above, and also has a strong bonding force with the first resin in the polymer alloy. Since the fusion force between the polymer alloy of the intermediate material 5 and the second member 3 is stronger than the fusion force with the first member 2, the fusion force between the intermediate material 5 and the second member 3 is sufficiently ensured. .

  Moreover, when welding the 1st member 2 and the 2nd member 3 by irradiation of the laser beam L, it receives the thermal cycle of being cooled after being heated. At this time, stress may be generated at the bonding interface due to a difference in linear expansion coefficient between the first member 2 and the second member 3. In contrast, since the intermediate member 5 has elasticity, the stress at the joint interface can be relaxed. As a result, it is possible to prevent a reduction in bonding strength and peeling.

  In addition, in the obtained bonded product 1, thermal stress or mechanical force is applied during use, and stress may be generated at the bonding interface between the first member 2 and the second member 3. Can be relieved by the presence of the intermediate material 5. Accordingly, the bonding strength can be maintained even when the bonded product 1 is used for a long period of time.

  As explained above, according to the joining method using the laser according to this embodiment, the first resin having the fusion property with the resin of the primer layer 4 applied to the first member 2, the second member 3, An intermediate material 5 made of a polymer alloy containing a second resin having a fusion bondability is arranged between the primer layer 4 and the second member 3, and the intermediate material 5 is heated by irradiating a laser beam. ing. As a result, when the first member 2 and the second member 3 are made of different materials and it is difficult to directly join the members 2 and 3, the members 2 and 3 are connected via the intermediate material 5 and the primer layer 4. Bonding can be performed with sufficient bonding strength. Therefore, the application range of the bonding method using laser light can be expanded.

  Further, since the fusion force between the polymer alloy of the intermediate material 5 and the second member 3 is set to be stronger than the fusion force between the polymer alloy and the first member 2, the bonding strength between the first member 2 and the second member 3. Can be further increased.

  Moreover, since the intermediate material 5 has a laser light absorber, the polymer alloy of the intermediate material 5 can be reliably heated and melted even when a low-power laser beam is used. Thus, the first resin in the polymer alloy and the resin of the primer layer 4 can be reliably fused, and the second resin in the polymer alloy and the second member 3 can be reliably fused, so that the first member 2 and the first resin The bonding strength with the two members 3 can be further increased.

  Further, since the primer layer 4 has a laser light absorber, the heat of the primer layer 4 heated by the laser light can be transmitted to the intermediate material 5 to surely melt the polymer alloy of the intermediate material 5. .

  In the above-described embodiment, the laser beam is irradiated from the second member 3 side. However, the present invention is not limited to this, and the first member 2 is constituted by a member having laser beam transparency, and the first member 2 side. You may make it irradiate a laser beam from. Thereby, the laser beam irradiated from the 1st member 2 side reaches the intermediate material 5, and the intermediate material 5 is heated.

  Moreover, the joining method using the laser beam concerning this invention is applicable when manufacturing various joining goods besides the components for motor vehicles, the case for cosmetics, the housing use, or the exterior member for electrical products, for example.

  Moreover, you may comprise the 1st member 2 with a metal other than resin, for example. In this case, the primer layer 4 should just have favorable adhesiveness with a metal.

  Embodiments of the present invention will be described below with reference to Table 1.

  The 1st member 2 is the same member in a comparative example and an example, and is a board material made of polypropylene. Specifically, as the polypropylene, Sun Allomer PM771M manufactured by Sun Allomer Co., Ltd. is used. The plate thickness of the first member 2 was 2 mm and the width was 25 mm. The laser transmittance is 7%.

  The 2nd member 3 is the same member by a comparative example and an Example, and is a board | plate material made from ABS. Specifically, Hishi Plate Y-268 manufactured by Mitsubishi Plastics, Inc. is used. The plate thickness of the second member 3 was 2 mm, and the width was 25 mm. The laser transmittance is 37%.

  The laser beam L was output from the semiconductor laser device, the wavelength was 940 nm, the output was 250 W, and the scanning speed was 1.2 m / min. The same applies to the comparative example and the example.

  First, a comparative example will be described. In the comparative example, the primer layer 4 is not formed. The first member 2 and the second member 3 were stacked in a range of width 25 mm × depth 35 mm with the intermediate material 5 interposed therebetween, irradiated with the laser light L from the second member 3 side, and scanned in the width direction. The first resin of the intermediate material 5 is SEBS, and the second resin is PMMA. SEBS is Tuftec H1041 manufactured by Asahi Kasei Corporation, and PMMA is Delpet 560F manufactured by Asahi Kasei Corporation. Moreover, 0.5 weight part of near-infrared absorption pigment | dye (IR-13F by Showa Denko KK) was added to the intermediate material 5 as a laser beam absorber. The thickness of the intermediate material 5 is 0.5 mm.

  As a result, it is possible to obtain only a weak bonding force that allows the first member 2 to be easily peeled from the second member 3 by hand, and cannot be put into practical use. Specifically, the test method of the bonding strength is that the first member 2 and the second member 3 in the bonded state are subjected to a tensile force in the shearing direction and in a direction orthogonal to the scanning direction of the laser beam L (a tensile speed of 5 mm / Min). In this test method, peeling was performed with a tensile force of 300N. In the comparative example, cleavage was easily generated.

  Next, examples of the present invention will be described. In the Example, the point which formed the primer layer 4 containing SEBS in the 1st member 2 differs from a comparative example, and others are the same as a comparative example. The application method of the primer layer 4 will be described. First, a 1% toluene solution of SEBS was made, and this was applied to the first member 2 three times using a brush.

  The result was difficult to peel off by hand. Specifically, peeling was performed with a tensile force of 1000 N by the above test method. Moreover, at the time of peeling, the 1st member 2 and the 2nd member 3 destroyed, permanent distortion produced, and it was not able to cleave. Thus, according to the present invention, it has been found that sufficient bonding strength can be obtained.

  As described above, the joining method using laser light according to the present invention can be used, for example, when manufacturing automotive parts, cosmetic cases, housing or electrical product exterior members, and the like.

DESCRIPTION OF SYMBOLS 1 Joining goods 2 1st member 3 2nd member 4 Primer layer 5 Intermediate material L Laser beam

Claims (4)

In a joining method of joining the first member and the second member formed by molding different materials by irradiating a laser beam in a state where an intermediate material is disposed between the two members,
Forming a primer layer for improving the fusion force with the intermediate material on the side of the first member joined to the second member;
Thereafter, the intermediate material composed of a polymer alloy containing a first resin having a fusibility with the resin contained in the primer layer and a second resin having a fusibility with the second member is formed on the primer layer. Arranged between the second member,
Next, in a state where the first member, the intermediate material, and the second member are stacked, the intermediate material is heated by irradiating a laser beam, and the first resin in the polymer alloy and the resin of the primer layer are combined. A bonding method using laser light, wherein the second resin in the polymer alloy and the second member are fused together while being fused. In the joining method using the laser beam according to claim 1,
A joining method using a laser beam, characterized in that the fusing force between the polymer alloy and the second member is set stronger than the fusing force between the polymer alloy and the first member. In the joining method using the laser beam according to claim 1 or 2,
A bonding method using laser light, wherein the intermediate material has an absorbent that absorbs laser light. In the joining method using the laser beam according to any one of claims 1 to 3,
The primer layer has an absorbent that absorbs laser light, and is a bonding method using laser light.

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