JP6629659B2 - Surface-treated aluminum material and method for producing the same, and composite molded article and method for producing the same - Google Patents

Description

  The present invention relates to a surface-treated aluminum material and a method for producing the same, and a composite molded article and a method for producing the same.

  2. Description of the Related Art In recent years, composite molded articles obtained by integrating a resin member and a metal member have been used as parts of automobiles and electronic devices. Such a resin-metal composite molded body is manufactured, for example, by insert molding in which a metal member is placed in a mold, and a thermoplastic resin is injected into the metal member and integrally molded. In such a resin-metal composite molded body, depending on the material used or the combination thereof, sufficient bonding strength between the resin member and the metal member that are injection-molded may not be obtained in some cases.

  Therefore, various studies have been made to improve the joining property between the resin member and the metal member in the resin-metal composite molded body. For a resin-metal composite molded body using an aluminum material or an aluminum alloy material as a metal member, a method of providing a fine uneven structure on the nanometer to micrometer level on the surface of the metal member by chemical immersion treatment (Japanese Patent Application Laid-Open No. 2007-182071) Japanese Patent Application Laid-Open No. 2013-052671 and Japanese Patent Application Laid-Open No. 2013-177004), a method of subjecting a surface to alumite treatment (see International Publication No. 2004/055248), and the like have been put to practical use. When these methods are used, the thermoplastic resin enters into fine irregularities and holes on the surface of the metal member during injection molding, and the bonding property is improved by a so-called anchor effect. On the other hand, a method of physically roughening the surface of a metal member using a laser or the like instead of a chemical treatment has also been put to practical use (see JP-A-2014-0665288). In this method, as in the case of surface roughening by chemical treatment, the bonding strength is improved by the anchor effect.

  Further, in order to improve the bonding strength between the metal member and the thermoplastic resin to be injected, there has been proposed a method in which a pregelling adhesive layer is formed on the surface of the metal member and the injection resin is bonded by insert formation (Japanese Patent Application Laid-Open (JP-A)). 2012-245665). The pregelling adhesive layer is formed by applying an epoxy resin adhesive and then heating. It is said that the bonding strength is improved by heating and hardening the epoxy resin forming the pregelling adhesive layer with a molten injection resin.

  However, these conventional techniques have disadvantages regarding applicability to large components, productivity, and economy as described below. Specifically, a method of forming fine irregularities or holes on the surface of a metal material requires a step of dipping in a predetermined treatment liquid and a step of laser processing. Therefore, when the aluminum or aluminum alloy material is subjected to a processing such as press working and then immersed in a processing liquid, for example, immersing a large-sized press-worked product requires time, resulting in poor productivity. In addition, capital investment and the like for a large processing tank are required, and the cost increases. The same applies to the case where laser processing is performed. For a large member, a large processing time is required, and there is a concern about productivity and cost. On the other hand, in the case of a method of forming a pregelling adhesive layer on a metal surface, a step of applying an epoxy resin in advance and semi-curing by heating is indispensable. It becomes.

JP 2007-182071 A JP 2013-052671 A JP 2013-177004 A International Publication No. 2004/055248 JP 2014-0665288 A JP 2012-245665 A

  The present invention has been made on the basis of the above circumstances, and has as its object to provide a surface-treated aluminum having excellent bonding properties with a polyamide resin and having good productivity and economical efficiency even when used as a large member. It is an object of the present invention to provide a material, a method for producing the same, a composite molded article using such a surface-treated aluminum material, and a method for producing the same.

  The invention made in order to solve the above-mentioned problem is a surface-treated aluminum material for insert molding which is composited with a resin containing polyamide, and a base material containing aluminum as a main component, and directly or under the base material. A resin film laminated via a ground film, wherein the resin film contains, as a main component, a polyesteramide having a hydroxyl group or an amino group at a terminal.

  The surface-treated aluminum material is provided with a resin film containing a polyesteramide having a hydroxyl group or an amino group at a terminal, so that it is excellently bonded to a resin containing a polyamide (hereinafter, also simply referred to as a “polyamide resin”). It can demonstrate its properties. Further, since this resin layer can be formed by, for example, applying a coating solution containing the above-mentioned polyesteramide, it is easy to form, and even when the surface-treated aluminum material is enlarged, productivity and economic efficiency are improved. Is good.

  It is preferable that the surface-treated aluminum material includes the above-described underlayer, and the underlayer is a chemical conversion coating, a plating coating, or a combination thereof. Since the base film is such a film, it can maintain excellent bonding properties with the polyamide resin even under severe environments, has excellent water resistance and moisture resistance, and is good even in a high temperature environment or an environment where temperature changes are severe. A composite molded article having excellent bonding properties can be obtained.

  The average thickness of the resin film is preferably from 10 μm to 500 μm per side. By setting the average thickness of one layer of the resin film in the above range, more excellent bonding properties can be exhibited.

  Another invention made in order to solve the above-mentioned problem is a method for producing a surface-treated aluminum material that is composited with a resin containing polyamide by insert molding, and the method comprises the steps of: A step of forming a resin film to be laminated on the material directly or via a base film, wherein the coating liquid contains a polyesteramide having a hydroxyl group or an amino group at a terminal as a main component.

  According to the production method, a resin film containing a specific polyesteramide can be formed on the surface of the base material, and a surface-treated aluminum material having excellent bonding properties with a polyamide resin can be obtained. In addition, since the manufacturing method can form a resin film by coating, even when applied to a large-sized base material or the like, productivity and economic efficiency are good.

  Yet another invention made to solve the above problem is a composite molded article of an aluminum member and a resin containing polyamide, wherein the aluminum member is the surface-treated aluminum material. Since the composite molded body uses the surface-treated aluminum material as the aluminum member, the composite molded body is excellent in bonding property with the polyamide resin.

  Yet another invention made in order to solve the above-mentioned problem is a method for manufacturing a composite molded body including a step of composite-molding an aluminum member and a resin containing polyamide by insert molding, wherein the aluminum member is used as the aluminum member. It is characterized by using a surface-treated aluminum material. According to the manufacturing method, it is possible to obtain a composite molded article having excellent bonding properties between the aluminum member and the polyamide resin.

  It is preferable that the method further includes a step of pressing the surface-treated aluminum material before the composite molding step. That is, in this case, for example, after a surface treatment is performed on a plate-shaped or sheet-shaped base material, the surface-treated aluminum material can be pressed and composited. This makes it possible to combine large members with good productivity and economy.

  The “terminal” of the polyesteramide refers to the terminal of the main chain of the polyesteramide. “Average thickness” refers to the average value of the thickness measured at any ten points. Further, the "average thickness per one side of the resin film" refers to the average thickness of the resin film laminated on one surface side of the substrate, for example, the substrate is a plate-like or the like, and the resin film on both sides Are laminated, this means the average thickness of the resin film laminated on each surface.

  ADVANTAGE OF THE INVENTION According to the surface-treated aluminum material and composite molded article of this invention, it has the outstanding joining property with a polyamide resin, and also when it is made into a large member, productivity and economical efficiency are favorable.

It is sectional drawing of the surface-treated aluminum material which concerns on one Embodiment of this invention. It is sectional drawing of the composite molded object provided with the surface-treated aluminum material of FIG. FIG. 3A is a plan view of the composite molded body of the example, and FIG. 3B is a side view thereof.

  Hereinafter, a surface-treated aluminum material according to an embodiment of the present invention, a method for manufacturing the same, a composite molded body, and a method for manufacturing the same will be described in detail with reference to the drawings as appropriate.

<Surface treated aluminum material>
The surface-treated aluminum material 10 in FIG. 1 is a three-layer structure including a base material 11 containing aluminum as a main component, a base film 12, and a resin film 13 in this order. The resin film 13 contains, as a main component, a polyesteramide having a hydroxyl group or an amino group at a terminal (hereinafter, also referred to as “specific polyesteramide”). The surface-treated aluminum material 10 is used as a member to be composited with a resin containing polyamide by insert molding, that is, as a member for insert molding to be composited with a resin containing polyamide. By providing the surface-treated aluminum material 10 with the resin film 13 containing the specific polyesteramide, it is possible to exhibit excellent bonding properties with the polyamide resin.

  The base material 11 contains aluminum as a main component. The main component is a component having the largest content on a mass basis. The content of aluminum in the base material 11 is preferably 80% by mass or more, and more preferably 95% by mass or more. It is preferable that the base material 11 is substantially made of aluminum or an aluminum alloy. Such a base material 11 may contain an additive in addition to aluminum or an aluminum alloy as long as the effects of the present invention are not affected. Examples of the aluminum alloy include an Al-Mg alloy, an Al-Mg-Si alloy, an Al-Zn-Mg alloy, an Al-Si alloy, and an Al-Cu alloy.

  The substrate 11 has a plate shape or a sheet shape. When the base material 11 is in a sheet shape, it may be formed in a coil shape. When the base material 11 has such a shape, productivity, mass productivity, handleability, and the like can be improved.

  In the substrate 11, the surface on the side to be bonded to the polyamide does not require any special roughening treatment. For example, the surface of the substrate 11 may be a mirror surface. The upper limit of the surface roughness Ra of the surface of the substrate 11 may be 5 μm, and preferably 1 μm. On the other hand, the lower limit of the surface roughness Ra of the substrate 11 can be, for example, 0.01 μm. The surface roughness Ra is an arithmetic mean roughness measured at a cutoff value (λc) of 2.5 mm and an evaluation length (l) of 12.5 mm in accordance with JIS-B-0601 (2001). Say.

  The base film 12 is laminated on the surface of the base material 11. The base film 12 is preferably formed by a chemical conversion treatment, a plating treatment, or a combination thereof on the surface of the base material 11. That is, the base film 12 is preferably a chemical conversion film, a plating film, or a combination thereof. In the case where the surface-treated aluminum material is used in an environment in which temperature and humidity changes are not particularly severe, good bonding properties with a polyamide resin can be exhibited even without a base film. However, it is preferable that such a base film 12 is formed when used in an environment in which temperature changes and humidity changes drastically or in an environment where water is wet. Since the surface-treated aluminum material 10 includes the base film 12, the bonding property between the base material 11 and the resin film 13 is improved, and the adhesion and the bonding durability between the surface-treated aluminum material 10 and the polyamide resin are enhanced. be able to.

  The chemical conversion film is a film formed by a chemical conversion treatment on the surface of the substrate 11. The chemical conversion treatment is generally a surface treatment method in which a treating agent acts on a metal material to generate a stable compound on the surface of the metal material. Examples of the chemical conversion treatment include a phosphoric acid chromate treatment, a chromate chromate treatment, a zirconium oxide treatment, a titanium zirconium treatment, a zinc phosphate treatment, and the like.The chromate phosphate treatment, a chromate chromate treatment, a zirconium oxide treatment, and a titanium zirconium treatment Processing is preferred. Further, a method of treating with an aqueous solution mainly containing sodium carbonate, sodium chromate, sodium silicate or the like (EW method or the like) is preferable, and among these, a method of treating with an aqueous solution of sodium silicate is more preferable. After these treatments, a post-treatment using a post-treatment agent (for example, “Surfcoat CM1706”, “Surfcoat 600H N-1”, etc., by Nippon Paint Co., Ltd.) to improve the adhesion and corrosion resistance of the film. You can also Further, as a special treatment, a chemical conversion treatment method in which after acid pickling with sulfuric acid, hydrofluoric acid, or the like, treatment with a silane coupling agent having an amino group or the like is also preferable. By performing these treatments, the base film 12 having a hydroxyl group or an amino group on the surface can be formed.

  The plating film refers to a film formed by plating the surface of the substrate 11. The plating treatment is generally a surface treatment method for forming a metal film using an oxidation-reduction reaction. Examples of the plating treatment include electrolytic plating such as zinc plating and chromium plating, and electroless plating such as electroless tin plating and electroless nickel plating.

  The chemical conversion treatment and the plating treatment can be performed by known methods. Note that the chemical conversion treatment and the plating treatment may be performed by combining a plurality of types of treatments.

  In the base film 12 formed by such a treatment, a polar group such as a hydroxyl group or an amino group is preferably exposed on the surface. That is, the base film 12 is preferably a film having a polar group on the surface (the surface in contact with the resin film 13). Due to the presence of a hydroxyl group or an amino group on the surface of the base film 12, the bondability with the resin film 13 containing the specific polyesteramide and the bondability between the surface-treated aluminum material 10 and the polyamide resin are further improved.

  The average thickness of the base film 12 is not particularly limited, but may be, for example, 10 nm or more and 10 μm or less. By setting the average thickness of the base film 12 within the above range, the bonding property can be further improved.

  The resin film 13 is laminated on the surface of the base material 11 with the base film 12 interposed therebetween. The resin film 13 contains the above-mentioned specific polyesteramide as a main component. As described above, by using a polyesteramide having a hydroxyl group or an amino group having a large polarity at the terminal, the surface-treated aluminum material 10 can exhibit good bonding properties with a polyamide resin. The main component is a component having the largest content on a mass basis. The content of the specific polyesteramide in the resin film 13 is preferably 80% by mass or more, and more preferably 95% by mass or more.

  The specific polyesteramide is a block copolymer in which a polyester component (hard segment) and a polyamide component (soft segment) are bonded by an amide bond or an ester bond. The polyester component is usually formed as a polymer of a dicarboxylic acid component and a diol component. Examples of the dicarboxylic acid component include a dimer acid component derived from a vegetable oil fatty acid. The polyamide component is usually formed as a polymer of a dicarboxylic acid component and a diamine component. Examples of the dicarboxylic acid component include a dimer acid component and other dibasic acid components. The dicarboxylic acid component preferably contains a dimer acid component and a short-chain dibasic acid component. The specific polyesteramide may contain components other than the polyesteramide component and the polyamide component as long as the effects of the present invention are not impaired.

  As the specific polyesteramide, commercially available products such as "TPAE-617" and "TPAE-617C" of T & K TOKA can be used.

  The resin film 13 may contain components other than the specific polyesteramide. Examples of the other components include polyesteramides other than the above-mentioned specific polyesteramide, other resins, additives, and the like.

  The lower limit of the average thickness of the resin film 13 is preferably 10 μm, more preferably 20 μm, and still more preferably 30 μm. By setting the average thickness of the resin film 13 to be equal to or more than the above lower limit, better bonding properties can be exhibited. On the other hand, the upper limit is, for example, 500 μm, and preferably 100 μm. If the average thickness of the resin film 13 exceeds the above upper limit, productivity and economic efficiency may decrease due to an increase in the amount of resin used.

<Production method of surface-treated aluminum material>
The method for producing the surface-treated aluminum material 10 is not particularly limited, but it can be suitably produced by the following method. That is, the method for manufacturing the surface-treated aluminum material 10 according to one embodiment of the present invention includes a step of forming a resin film 13 laminated on the base material 11 via the base film 12 by using a coating liquid. The working fluid is characterized by containing a polyesteramide having a hydroxyl group or an amino group at a terminal as a main component.

  The formation of the base film 12 can be performed by a chemical conversion treatment, a plating treatment, or the like as described above. It is preferable that a degreasing treatment is performed on the surface of the base material 11 before the formation of the base film 12.

  The coating liquid contains the specific polyesteramide as a main component. Here, the main component of the coating liquid refers to a component having the largest content on a mass basis in the solid content. The solid content refers to components other than the solvent. In addition, the above-mentioned specific polyesteramide shows good solubility in non-aromatic organic solvents and aromatic organic solvents.

  Examples of the solvent of the coating liquid include non-aromatic organic solvents such as ethanol, n-propanol, isopropanol and alcohols having 1 to 8 carbon atoms such as n-butanol, ketones having 3 to 8 carbon atoms such as cyclohexanone and dimethylacetamide. , Dimethylformamide, N-methyl-2-pyrrolidone and the like. Among these, isopropanol, cyclohexanone, dimethylacetamide, dimethylformamide and N-methyl-2-pyrrolidone are preferred from the viewpoint of solubility of the specific polyesteramide. Further, from the viewpoint of solubility, mixed solvents such as cyclohexane / n-propanol, cyclohexanone / n-propanol, and isopropanol / hexane are also preferable.

  Examples of the solvent for the coating liquid include toluene and xylene as aromatic solvents. Further, a mixed solvent of an aromatic solvent and a non-aromatic solvent is also preferable. Examples of the non-aromatic solvent mixed with the aromatic solvent include the above-mentioned alcohols, ketones, and amide compounds. Examples of the mixed solvent having good solubility include a mixed solvent of toluene and methanol or isopropanol, and a mixed solvent of xylene and n-butanol.

  The specific polyesteramide may be dissolved in a solvent while heating and refluxing. The heating and reflux temperature at this time is appropriately set according to the type of the solvent, and may be, for example, 80 ° C. or more and 150 ° C. or less.

  The solid content concentration or the specific polyesteramide concentration in the coating liquid can be, for example, 5% by mass or more and 40% by mass or less.

  The coating of the coating liquid can be performed by a known method using, for example, a known roll coating equipment. The application of the coating liquid includes immersion of the base material 11 in the coating liquid, spraying of the coating liquid, and the like. After coating, the resin film 13 is preferably formed by heating and drying the coating film using a heating furnace or the like. The heating temperature at the time of drying is appropriately adjusted depending on the apparatus used, the type of solvent, and the like, but is preferably 180 ° C. or higher. The upper limit of the heating temperature can be, for example, 240 ° C.

  According to the manufacturing method, since the resin film 13 can be formed by coating, even when applied to the large-sized base material 11, it is excellent in productivity, mass productivity, economy, and the like. For example, when the base material 11 is in a sheet shape, the resin film 13 can be formed into a coil shape after being formed, or the coil-shaped base material 11 can be immersed in a coating liquid to form the resin film 13. .

<Composite molded body>
2 includes a surface-treated aluminum material 10 and a polyamide resin portion 21 formed of a resin containing polyamide (polyamide resin). The composite molded body 20 is a composite molded body of an aluminum member (the surface-treated aluminum material 10) and a polyamide resin. The composite laminate is usually formed by insert molding. Since the composite molded body uses the surface-treated aluminum material 10 as an aluminum member, the composite molded body has good bondability with a polyamide resin.

  The surface-treated aluminum material 10 of FIG. 2 is the same as the surface-treated aluminum material 10 of FIG.

  The polyamide resin portion 21 is laminated on the surface of the resin film 13 of the surface-treated aluminum material 10. The polyamide resin portion 21 is formed from a polyamide resin injected during insert molding. As the polyamide contained in the polyamide resin, a commercially available polyamide for injection molding can be used. Examples of the polyamide include an aliphatic polyamide, an aromatic polyamide, a polyamide elastomer, a mixture thereof, and a copolymer polyamide thereof, and an aliphatic polyamide is preferable. Further, nylon 6, nylon 66, nylon 46, nylon 610, nylon 612 and nylon 12 are preferred, and nylon 6 and nylon 66 are more preferred.

  It is preferable that the polyamide resin portion 21 contains a filler. By the filler, the difference in linear expansion coefficient between the surface-treated aluminum material 10 and the polyamide resin portion 21 can be adjusted, and the mechanical strength of the polyamide resin portion 21 can be increased. The content of the filler is preferably from 10 parts by mass to 150 parts by mass with respect to 100 parts by mass of the polyamide. Examples of the filler include a fibrous filler, a plate-like filler, and a granular filler. Examples of the fibrous filler include glass fiber, carbon fiber, and aramid fiber. For example, the glass fibers include chopped strands having an average fiber diameter of 5 μm or more and 15 μm or less. Examples of the plate-like or granular filler include talc, mica, glass flake, calcium carbonate, barium sulfate, silica and the like.

  The polyamide resin portion 21 may further contain components other than the polyamide and the filler. Other components include polymers other than polyamides and additives other than fillers. However, the content of components other than the polyamide and the filler in the polyamide resin portion 21 is preferably 20% by mass or less, and more preferably 5% by mass or less. When the content of other components increases, the bondability with the surface-treated aluminum material 10 may decrease.

<Method for producing composite molded article>
The composite molded body 20 can be suitably manufactured by the following method. That is, the method of manufacturing the composite molded body 20 according to one embodiment of the present invention is a method of manufacturing a composite molded body including a step of composite-molding an aluminum member and a polyamide resin by insert molding. The surface-treated aluminum material 10 is used. In the manufacturing method, the polyamide resin portion 21 is formed by the polyamide resin injected during insert molding. In the said manufacturing method, except having used the said surface-treated aluminum material 10 as an aluminum member, it can be performed like the conventionally well-known insert molding.

  It is preferable that the method further includes a step of pressing the surface-treated aluminum material 10 before the composite molding step. That is, for example, it is preferable to obtain the surface-treated aluminum material 10 using the plate-shaped or sheet-shaped base material 11, press-process the surface-treated aluminum material 10, and then obtain a composite molded body by insert molding. By manufacturing the composite molded body in such a process, it is not necessary to perform a surface treatment on the pressed aluminum material. Accordingly, this allows efficient production of a large-sized composite molded article having a complicated shape.

  After the press working, the oil component such as press oil that has been used in the press working and adhered to the surface-treated aluminum material 10 needs to be removed by degreasing or the like before the composite forming step. Here, at the time of press working, it is preferable to use volatile press oil. By using a volatile press oil, the oil component can be removed by leaving at room temperature or heating, and the degreasing step can be omitted and the cost can be reduced.

  According to the method for manufacturing a composite molded article, since the composite with the polyamide resin is formed using the surface-treated aluminum material 10 in this manner, a composite molded article having excellent bonding properties can be obtained. Therefore, according to the method for manufacturing a composite molded article, adhesive bonding, bolting, surface roughening treatment of the aluminum material, and the like are not required, and productivity, mass productivity, economy, and the like can be improved.

<Other embodiments>
The surface-treated aluminum material of the present invention and the method for producing the same, and the composite molded article and the method for producing the same are not limited to the above embodiments. For example, in a surface-treated aluminum material, a base film may not be formed, and a resin film may be directly laminated on a base material. In this case, a surface-treated aluminum material can be obtained by applying a coating solution containing the specific polyesteramide to the substrate. Further, the resin film and the base film may be laminated on only a part of one surface of the base material, or may be laminated on both surfaces or the whole surface. Further, the base material may have a complicated shape other than the plate shape or the sheet shape, for example, a pressed shape or the like.

  Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

<Example 1>
After degreasing an aluminum material (A5052P-H34 of JIS-H-4000 (2014)) having a length of 300 mm, a width of 200 mm and a thickness of 1 mm, Nippon Paint Co., Ltd.'s "Alsurf 401KB-2 (main agent) and Alsurf 45KB (adjuvant agent) )) "To perform a phosphoric acid chromate treatment (Cr: 15 mg / m ² ). A polyester amide pellet having a hydroxyl group terminal ("TPAE-617" manufactured by T & K TOKA) is heated at 120 ° C with stirring in a solvent obtained by mixing equal amounts of toluene and isopropanol so as to have a solid content of 30% by mass. After dissolution under reflux, the mixture was cooled to room temperature to obtain a coating liquid. This coating solution was applied to the surface of the aluminum material treated with phosphoric acid chromate by a bar coating method. Next, baking was performed at 185 ° C. for 120 seconds to obtain a surface-treated aluminum material on which a resin film having an average thickness of 30 μm was formed.

  Next, a composite molded body 30 as an evaluation test piece shown in FIG. 3 was obtained by the following method. Using a 55-ton injection molding machine (“JSW J55EL II” manufactured by Nippon Steel Works), a mold capable of installing a surface-treated aluminum material 31 of 25 mm width × 100 mm length × 1 mm thickness on a movable mold plate. A shape and a mold shape capable of pasting an injection resin (polyamide resin part 32) having a width of 23 mm × 100 mm length × 3 mm thickness on a fixed mold plate were prepared. On the other hand, the surface-treated aluminum material obtained in the previous step was cut into a width of 25 mm and a length of 100 mm. This was set in the movable mold, and the movable mold and the fixed mold were tightened. Next, a polyamide resin for injection molding (nylon 6: “Amilan CM1011G-30” manufactured by Toray Industries, Inc .: containing 30% by mass of glass fiber) which was previously dehumidified at 90 ° C. for 3 hours was injected, and the surface-treated aluminum material 31 shown in FIG. A composite molded body 30 as an evaluation test piece including the polyamide resin portion 32 was obtained. The injection conditions were a resin melting temperature of 260 ° C. on the molding machine side, a mold temperature of 75 ° C., an injection resin pressure of 150 MPa, an injection holding pressure of 45 MPa, a holding time of 10 seconds, and a cooling time of 18 seconds.

<Example 2>
Example 1 except that the polyesteramide pellet having a hydroxyl group terminal (“TPAE-617” manufactured by T & K TOKA) was replaced with a polyesteramide pellet having an amino group terminal (“TPAE-617C” manufactured by T & K TOKA). Similarly, a surface-treated aluminum material and a composite molded article as an evaluation test piece were obtained.

<Example 3>
A 300 mm long, 200 mm wide, 1 mm thick aluminum material (A5052P-H34 of JIS-H-4000 (2014)) was degreased with a mixed solution of sulfuric acid and hydrofluoric acid, and then adjusted to a concentration of 0.12%. After being immersed (about 10 seconds) in the aqueous sodium silicate solution, it was dried. Thereafter, the aluminum material was immersed (about 10 seconds) in a solution of “Surfcoat CM1706” manufactured by Nippon Paint Co., Ltd., and dried to obtain an aluminum material having a base film. Then, in the same manner as in Example 1, a polyesteramide pellet having a hydroxyl group terminal (“TPAE-617” manufactured by T & K TOKA) was added to a solvent obtained by mixing equal amounts of toluene and isopropanol so as to have a solid content of 30% by mass. Was heated and refluxed at 120 ° C. with stirring, and then cooled to room temperature to obtain a coating liquid. This coating liquid was applied to the surface of the above-mentioned chemical conversion-treated aluminum material by a bar coating method. Next, baking was performed at 185 ° C. for 120 seconds to obtain a surface-treated aluminum material on which a resin film having an average thickness of 30 μm was formed. Next, using this surface-treated aluminum material, a composite molded body as an evaluation test piece was obtained in the same manner as in Example 1.

<Example 4>
Example 3 except that the polyesteramide pellet having a hydroxyl group terminal (“TPAE-617” manufactured by T & K TOKA) was replaced by a polyesteramide pellet having an amino group terminal (“TPAE-617C” manufactured by T & K TOKA). Similarly, a surface-treated aluminum material and a composite molded article as an evaluation test piece were obtained.

<Comparative Example 1>
The molding of the composite molded body by insert molding was attempted in the same manner as in Example 1 except that the aluminum material subjected to the phosphoric acid chromate treatment was used as it was, and the resin film was not formed. However, the aluminum material and the polyamide were not joined.

<Comparative Example 2>
In a solvent in which toluene and isopropanol are mixed in equal amounts, a polyetheresteramide pellet having no functional group terminal ("TPAE-32" manufactured by T & K TOKA) is stirred with a solid content of 25% by mass while stirring. The mixture was dissolved by heating at 120 ° C. under reflux. Thereafter, the mixture was cooled to room temperature to obtain a coating liquid, and this coating liquid was used. Except for this point, a surface-treated aluminum material and a composite molded article as an evaluation test piece were obtained in the same manner as in Example 1.

<Comparative Example 3>
In a solvent in which toluene and isopropanol are mixed in an equal amount, a polyetheresteramide pellet having no functional group terminal (“PA-201” manufactured by T & K TOKA) is stirred so as to have a solid content of 25% by mass. The mixture was dissolved by heating at 120 ° C. under reflux. Thereafter, the mixture was cooled to room temperature to obtain a coating liquid, and this coating liquid was used. Except for this point, a surface-treated aluminum material and a composite molded article as an evaluation test piece were obtained in the same manner as in Example 1.

<Evaluation method>
A tensile test was performed at room temperature on the obtained composite molded body as an evaluation test piece. The tensile test was performed using a tensile tester by pulling the evaluation test piece until it was broken in the longitudinal direction. The tensile shear strength was calculated from the load at break and the joint area. As the tensile tester, a universal tester “3369 type” manufactured by Instron Japan Limited was used. In addition, the tensile speed was set to 100 mm / min, and each test was performed with the number of tests n = 5, and the average of three values excluding the minimum value and the maximum value was defined as the tensile shear strength. However, this test was not performed for Comparative Example 1 because injection joining was not performed.

In addition to the measurement of the initial tensile shear strength at room temperature, a tensile test under the following environmental load was performed to measure the tensile shear strength. However, since the injection joining was not performed for Comparative Example 1, these environmental impact tests were not performed.
1) Immersion in warm water: A tensile test was performed after immersion in distilled water at 70 ° C. for 200 hours.
2) Constant temperature / humidity: A tensile test was performed after leaving at 500C-85% relative humidity for 500 hours.
3) Cooling / heating cycle: Ten cycles were performed after repeating -20 ° C. × 7 hours and 120 ° C. × 17 hours (switching time: 1 minute) for 5 cycles.
4) At 80 ° C atmosphere: A tensile test was performed at 80 ° C atmosphere.

  In a tensile test at room temperature, the state of breakage was observed. The case where the resin part was broken, that is, the aluminum material had an injection resin residue, was evaluated as A, and the case where the aluminum material was separated at the interface between the aluminum material and the resin part, that is, the aluminum material had no injection resin residue, was evaluated as B. . In addition, about the comparative example 1, since injection joining was not able to be performed, the observation of the breaking state was not performed.

  Table 1 shows the results of the above evaluations. In addition, the column of “immersion in warm water” of Comparative Example 2 in Table 1 indicates that peeling occurred during immersion in warm water.

  As shown in Table 1 above, in Examples 1, 2, 3 and 4, the tensile shear strength was 5 MPa or more in the initial state at room temperature and in the state under any environmental load. It is shown to have good bonding properties. Further, in Examples 1, 2, 3, and 4, it can be seen from the fact that the resin portion was broken, which indicates that the aluminum material and the polyamide resin are strongly bonded.

  INDUSTRIAL APPLICABILITY The surface-treated aluminum material and the composite molded article of the present invention and a method for producing the same can be suitably used for parts of devices such as automobiles and electronic devices and the production thereof.

DESCRIPTION OF SYMBOLS 10 Surface aluminum material 11 Base material 12 Base film 13 Resin film 20 Composite molded body 21 Polyamide resin part 30 Composite molded body 31 Surface treated aluminum material 32 Polyamide resin part

Claims (7)

A surface-treated aluminum material for insert molding to be compounded with a resin containing polyamide,
A base material mainly composed of aluminum;
And a resin film laminated over the lower Chimaku on the substrate,
A surface-treated aluminum material, wherein the resin film contains a polyesteramide having a hydroxyl group or an amino group at a terminal as a main component. Upper SL under Chimaku is, conversion coating, plating layer or surface-treated aluminum material according to claim 1 which is a combination thereof.   The surface-treated aluminum material according to claim 1, wherein an average thickness of the resin film is 10 μm or more and 500 μm or less per one surface. A method for producing a surface-treated aluminum material that is composited with a resin containing polyamide by insert molding,
The coating solution, comprising the step of forming a resin film laminated over the lower Chimaku the base material mainly composed of aluminum, the coating liquid, a polyester having terminal hydroxyl group or an amino group as a main component A method for producing a surface-treated aluminum material, comprising an amide.   A composite molded article of an aluminum member and a resin containing polyamide, wherein the aluminum member is the surface-treated aluminum material according to claim 1, 2, or 3. .   4. A method for producing a composite molded body comprising a step of composite-molding an aluminum member and a resin containing polyamide by insert molding, wherein the aluminum member is a surface treatment according to claim 1, 2 or 3. A method for producing a composite molded body, comprising using an aluminum material.   The method for producing a composite molded body according to claim 6, further comprising a step of pressing the surface-treated aluminum material before the composite molding step.

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