Anodized aluminum component, method for manufacturing the same, method for manufacturing surface-treated aluminum component, and printed circuit board

Abstract

The present invention provides an anodized aluminum component that suppresses the unintended formation of hydrated oxides and allows for the formation of hydrated oxides at a desired timing, a method for manufacturing the same, a method for manufacturing a surface-treated aluminum component, and a printed circuit board. [Solution] The anodized aluminum member 1 comprises a base material 2 made of aluminum or an aluminum alloy, and an anodized coating 3 covering the base material 2. The anodized coating 3 comprises a barrier layer 31 provided on the base material 2, and a porous layer 32 provided on the barrier layer 31 and having a plurality of pores 321. When the elemental concentration on the surface of the anodized coating 3 is calculated based on the photoelectron spectrum obtained by X-ray photoelectron spectroscopy, the ratio of the concentration of P atoms to the concentration of Al atoms is 0.03 or more and 0.11 or less.

Description

[Technical Field]

[0001] The present invention relates to anodized aluminum members, methods for manufacturing the same, methods for manufacturing surface-treated aluminum members, and printed circuit boards. [Background technology]

[0002] An anodized coating may be formed on the surface of aluminum components for various purposes, such as improving scratch resistance, corrosion resistance, adhesion, and decorative properties. The anodized coating consists of a barrier layer formed on the base material that does not have pores, and a porous layer formed on the barrier layer that has pores. Depending on the application of the anodized aluminum component, a sealing treatment may be performed to close the pores in the porous layer. The sealing treatment is performed by bringing a sealing agent such as hot water, steam, or a metal salt into contact with the anodized coating and forming a hydrated oxide on the surface of the anodized coating (for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-141525 [Overview of the project] [Problems that the invention aims to solve]

[0004] However, the aluminum oxides that make up the anodic oxide film also hydrate with moisture in the atmosphere to form hydrated oxides. Therefore, if aluminum components that have undergone anodic oxidation are stored in the atmosphere, the surface properties may change due to the unintended formation of hydrated oxides, potentially leading to a deterioration of properties such as adhesion. Furthermore, if hydrated oxides are formed in the pores, it may become difficult for colorants such as dyes and pigments to penetrate the pores, potentially making it difficult to dye the aluminum components.

[0005] This invention has been made in view of the above background, and aims to provide an anodized aluminum member that can suppress the formation of unintended hydrated oxides and form hydrated oxides at a desired timing, a method for manufacturing the same, a method for manufacturing a surface-treated aluminum member, and a printed circuit board. [Means for solving the problem]

[0006] A first aspect of the present invention is a base material made of aluminum or an aluminum alloy, The base material has an anodic oxide coating covering it, The anodic oxide film comprises a barrier layer provided on the base material, The barrier layer is provided on the aforementioned barrier layer and comprises a porous layer having a plurality of pores, The anodized aluminum component is characterized in that the photoelectron spectrum of the surface of the anodized film is measured by X-ray photoelectron spectroscopy, and when the elemental concentrations are calculated based on the photoelectron spectrum, the ratio of the concentration of P atoms to the concentration of Al atoms is 0.03 or more and 0.11 or less.

[0007] A second aspect of the present invention is a method for manufacturing a surface-treated aluminum member according to the above aspect, In an electrolyte solution comprising one or more primary electrolytes selected from the group consisting of phosphoric acid, diphosphate, triphosphate, and polyphosphate, and one or more secondary electrolytes selected from the group consisting of inorganic acids other than the acids contained in the primary electrolyte, carboxylic acids, and salts thereof, wherein the concentration of the primary electrolyte is 0.1% by mass or more and 3% by mass or less, and the concentration of the secondary electrolyte is 1% by mass or more and 30% by mass or less, the current density is 2 mA / cm². 2 More than 150mA / cm 2 The following describes a method for manufacturing a surface-treated aluminum member, in which the base material is subjected to anodizing treatment under conditions of a temperature between 0°C and 80°C.

[0008] A third aspect of the present invention is a method for manufacturing a surface-treated aluminum member using the anodized aluminum member of the above aspect, The surface of the anodized aluminum member is activated by cleaning it with an acid that does not contain phosphorus atoms. The present invention relates to a method for manufacturing a surface-treated aluminum member, wherein the anodic oxide film is then brought into contact with a sealing agent to seal the pores in the porous layer.

[0009] A fourth aspect of the present invention is a printed circuit board including the anodized aluminum member of the above aspect. [Effects of the Invention]

[0010] In the aforementioned anodized aluminum member (hereinafter referred to as the "anodicized member"), the ratio of the concentration of P atoms to the concentration of Al atoms on the surface of the anodized film is 0.03 or more and 0.11 or less. The P atoms present on the surface of the anodized film can suppress the progress of the hydration reaction of the aluminum oxide constituting the anodized film. Therefore, by keeping the ratio of the concentration of P atoms to the concentration of Al atoms on the surface of the anodized film within the aforementioned specific range, the formation of unintended hydrated oxides due to reactions with moisture in the atmosphere can be suppressed.

[0011] Furthermore, an anodized member whose concentration ratio is within the specified range can have its surface activated by cleaning the anodized film with acid. After activating the anodized film, contacting the anodized film with a sealing agent allows for the easy formation of hydrated aluminum oxide, thereby sealing the pores in the porous layer. Therefore, the anodized member can form hydrated oxide on the surface of the anodized film at a desired timing.

[0012] In the method for manufacturing the anodic oxide member, by performing an anodic oxidation treatment on the base material in the specific electrolyte under the specific conditions, an anodic oxide film can be easily formed in which the ratio of the concentration of P atoms to the concentration of Al atoms on the surface, P / Al, is within the specific range.

[0013] In the method for manufacturing the surface-treated aluminum member (hereinafter referred to as "surface-treated member"), the anodic oxide member can be washed with an acid to activate the surface of the anodic oxide film. Then, after activating the anodic oxide film, by bringing the anodic oxide film into contact with a sealing agent, the hydration reaction of the aluminum oxide can be easily advanced, and the pores can be sealed.

[0014] Therefore, according to the above aspect, it is possible to provide an anodic oxidation aluminum member that suppresses the formation of unintended hydrated oxides and can form hydrated oxides at a desired timing, a method for manufacturing the same, a method for manufacturing a surface-treated aluminum member, and a printed wiring board.

Brief Description of the Drawings

[0015] [Figure 1] FIG. 1 is a partial cross-sectional view of the anodic oxidation aluminum member in the embodiment.

Embodiments for Carrying Out the Invention

[0016] (Anodic Oxidation Aluminum Member) The base material of the anodic oxidation member is composed of aluminum or an aluminum alloy. The shape of the base material is not particularly limited and can take various shapes according to the use of the aluminum member. For example, the base material may be an extended material such as a rolled plate or an extruded material, or a cast material or a forged material.

[0017] In addition, the material of the base material can be appropriately selected from the group consisting of aluminum and aluminum alloys according to the use of the aluminum member. More specifically, for example, 1000 series aluminum can be used as the aluminum constituting the base material. As the aluminum alloy constituting the base material, for example, 2000 series aluminum alloy, 3000 series aluminum alloy, 4000 series aluminum alloy, 5000 series aluminum alloy, 6000 series aluminum alloy, 7000 series aluminum alloy, and 8000 series aluminum alloy can be used. Further, the base material may be a clad material in which two or more layers having different chemical components are laminated.

[0018] The anodized member has an anodic oxide film covering the base material. The anodic oxide film is composed of an oxide of aluminum. The anodic oxide film may cover the entire surface of the base material or may cover a part of the surface of the base material. The thickness of the anodic oxide film is not particularly limited, but can be appropriately set, for example, within the range of 50 nm or more and 50 μm or less.

[0019] The anodic oxide film has a barrier layer provided on the base material and a porous layer provided on the barrier layer and having a plurality of pores. The thickness of the barrier layer is 10 nm or more and 150 nm or less, and the thickness of the porous layer is preferably 100 nm or more. In this case, formation of unintended hydrated oxides can be more reliably suppressed, and hydrated oxides can be formed at a desired timing.

[0020] The photoelectron spectrum of the surface of the anodic oxide film is measured by X-ray photoelectron spectroscopy, and when the elemental concentrations are calculated based on this photoelectron spectrum, the ratio of the concentration of P atoms to the concentration of Al atoms is between 0.03 and 0.11. An anodized member equipped with such an anodized film can suppress the formation of unintended hydrated oxides due to the hydration reaction between moisture in the atmosphere and aluminum oxide. Furthermore, the surface of the anodized member can be activated by cleaning the surface of the anodized film with acid. Then, by bringing a sealing agent into contact with the anodized film after the surface has been activated, the pores of the porous layer can be easily sealed at a desired timing.

[0021] Anodized materials with a ratio of P atom concentration to Al atom concentration of less than 0.03 are prone to hydration reactions between moisture in the atmosphere and aluminum oxide, making it difficult to suppress the formation of unintended hydrated oxides. On the other hand, anodized materials with a ratio of P atom concentration to Al atom concentration exceeding 0.11 are difficult to activate the surface of the anodic oxide film even when cleaned with acid. Therefore, it is difficult to form aluminum hydrated oxides on the surface of the anodic oxide film.

[0022] The reason why the aforementioned anodic oxide material has such effects is not yet clear, but it is thought that the effects described above can be obtained for the following reasons, for example. Anions of electrolytes containing phosphorus atoms, such as phosphoric acid and diphosphate, used in the manufacturing process of the anodic oxide material, are adsorbed on the surface of the anodic oxide film of the material. These anions are thought to inhibit the hydration reaction between aluminum oxide and water. Therefore, it is thought that by setting the ratio of the concentration of P atoms to the concentration of Al atoms to 0.03 or higher, a sufficient amount of anions containing phosphorus atoms can be adsorbed on the surface of the anodic oxide film of the material. It is thought that the anions adsorbed on the surface of the anodic oxide film can suppress the formation of unintended hydrated oxides.

[0023] Furthermore, anions adsorbed on the surface of the anodic oxide film are detached from the surface of the anodic oxide film when the film is washed with acid. It is thought that the detachment of phosphorus-containing anions from the surface of the anodic oxide film makes the hydration reaction between aluminum oxide and water more likely to occur. Therefore, it is thought that by setting the ratio of the concentration of P atoms to the concentration of Al atoms to 0.11 or less, the amount of anions adsorbed on the surface of the anodic oxide film can be reduced to an amount that can be easily removed by washing with acid. By controlling the amount of anions adsorbed on the surface of the anodic oxide film in this way, it is thought that the anodic oxide film can be activated at a desired timing by washing with acid, thereby sealing the pores of the porous layer.

[0024] From the viewpoint of more reliably obtaining the aforementioned effects, it is preferable that the ratio of the sum of the concentrations of Al atoms and P atoms to the sum of the concentrations of Al atoms, P atoms and O atoms, when the photoelectron spectrum of the surface of the anodic oxide film is measured by X-ray photoelectron spectroscopy and the elemental concentrations are calculated based on this photoelectron spectrum, be between 0.280 and 0.315.

[0025] Furthermore, the specific surface area of ​​the anodic oxide film measured by the BET method is 0.1 m². 2 / g or more 10.0m 2 It is preferable that the amount be less than or equal to / g. In this case, the effects described above can be obtained more reliably.

[0026] The applications of the anodized material are not particularly limited, but it is preferable, for example, to use it as a component of a printed circuit board where a highly reliable bond between the resin and the substrate is required.

[0027] (Method for manufacturing anodized aluminum components) The anodizing member comprises one or more primary electrolytes selected from the group consisting of phosphoric acid, diphosphate, triphosphate, polyphosphate, and salts thereof, and one or more secondary electrolytes selected from the group consisting of inorganic acids other than acids contained in the primary electrolyte, carboxylic acids, and salts thereof, wherein the concentration of the primary electrolyte is 0.1% by mass or more and 3% by mass or less, and the concentration of the secondary electrolyte is 1% by mass or more and 30% by mass or less, and the current density is 2 mA / cm² in the electrolyte solution. 2 More than 150mA / cm 2 The following is obtained by performing an anodic oxidation treatment on the base material under conditions of a temperature between 0°C and 80°C.

[0028] In the above manufacturing method, when anodizing is performed under the specific conditions, the dissolution of aluminum and the growth of aluminum oxide proceed in parallel at the interface between the base material and the electrolyte. As a result, an anodic oxide film having a barrier layer and a porous layer is formed on the base material. Furthermore, during the growth process of the anodic oxide film, some anions derived from the first electrolyte and some anions derived from the second electrolyte are incorporated into the anodic oxide film. Therefore, the anodic oxide film formed on the base material may contain anions derived from the first electrolyte and anions derived from the second electrolyte, in addition to aluminum oxide. After the anodizing process is completed, anions containing phosphorus atoms derived from the first electrolyte are adsorbed onto the surface of the anodic oxide film. As a result, the anodic oxide member can be obtained.

[0029] From the viewpoint of more easily obtaining the anodic oxidation member, the first electrolyte is preferably one or more salts selected from the group consisting of phosphates, diphosphates, triphosphates, and polyphosphates, more preferably diphosphates, and even more preferably sodium diphosphate.

[0030] When the concentration of the primary electrolyte in the electrolyte solution is less than 0.1% by mass, the amount of phosphorus-containing anions adsorbed on the surface of the anodic oxide film decreases, making the aluminum oxide constituting the anodic oxide film more susceptible to hydration reactions. Therefore, it is difficult to suppress the formation of unintended hydrated oxides in anodic oxide components manufactured under such conditions.

[0031] When the concentration of the primary electrolyte in the electrolyte exceeds 3% by mass, the amount of phosphorus-containing anions adsorbed on the surface of the anodic oxide film increases, and a large amount of anions tend to remain on the surface of the anodic oxide film after acid washing. Therefore, it is difficult to activate the anodic oxide film and seal the pores of the porous layer at the desired timing in anodic oxide components manufactured under such conditions.

[0032] If the concentration of the secondary electrolyte in the electrolyte is less than 1% by mass, the anodic oxidation reaction is less likely to occur at the interface between the base material and the electrolyte, making it difficult to form an anodic oxide film on the base material. If the concentration of the secondary electrolyte in the electrolyte exceeds 30% by mass, the dissolving power of the electrolyte becomes excessively high, making it difficult to form an anodic oxide film on the base material.

[0033] Current density in anodizing process is 2 mA / cm² 2 If the current density is less than 150 mA / cm², the anodic oxidation reaction is less likely to occur at the interface between the base material and the electrolyte, making it difficult to form an anodic oxide film on the base material. 2 If the value exceeds this, areas where the anodic oxidation reaction proceeds easily and areas where it does not tend to form at the interface between the base material and the electrolyte, making it difficult to form a uniform anodic oxide film on the base material.

[0034] In the anodizing process, the anodic oxide film may be formed by any of the following methods: DC electrolysis, AC electrolysis, or pulse electrolysis. From the viewpoint of more easily obtaining the anodic oxide member, it is preferable to form the anodic oxide film on the base material by DC electrolysis or AC electrolysis in the anodizing process, and it is more preferable to form the anodic oxide film on the base material by DC electrolysis.

[0035] If the electrolyte temperature in the anodizing process is below 0°C, the anodizing reaction becomes less likely to occur, making it difficult to form an anodic oxide film on the base material. If the electrolyte temperature in the anodizing process exceeds 80°C, the porous layer is more likely to dissolve during the anodizing process, making it difficult to form a porous layer on the base material.

[0036] The processing time for anodizing is not particularly limited and can be set appropriately according to the current density, applied voltage, and desired thickness of the anodized film. More specifically, the processing time for anodizing can be set appropriately within a range of, for example, 1 minute to 6 hours.

[0037] In the above manufacturing method, pretreatment such as degreasing, etching, desmatting, polishing, and grinding may be performed on the base material as needed before anodic oxidation treatment.

[0038] (Method for manufacturing surface-treated aluminum components) A surface-treated aluminum member can be obtained by sealing the pores in the porous layer of the anodized member. More specifically, in manufacturing the surface-treated member, the surface of the anodized aluminum member is activated by washing it with an acid that does not contain phosphorus atoms. Subsequently, the pores in the porous layer can be sealed by bringing the anodic oxide film into contact with a sealing agent.

[0039] In the method for manufacturing the surface-treated member, an acid that does not contain phosphorus atoms can be used as the acid used to activate the surface of the anodic oxide film. Examples of such acids include inorganic acids that do not contain phosphorus atoms, such as sulfuric acid, nitric acid, and hydrochloric acid, and carboxylic acids such as oxalic acid.

[0040] The acid used to activate the surface of the anodic oxide film is preferably an acid capable of dissolving aluminum oxide. That is, in the above manufacturing method, it is preferable to activate the surface of the anodic oxide film by washing the anodic oxide member with an acid capable of dissolving aluminum oxide and dissolving the surface of the anodic oxide film. Examples of such acids include oxalic acid. By dissolving the surface of the anodic oxide film in this way, anions containing phosphorus atoms adsorbed on the surface of the anodic oxide film can be removed more easily. As a result, the anodic oxide film can be activated more reliably, and when the activated anodic oxide film is brought into contact with the sealing agent, hydrated oxides can be formed more reliably, sealing the pores of the porous layer.

[0041] The concentration of the acid used to activate the surface of the anodized film and the contact time between the anodized film and the acid are not particularly limited. The concentration of the acid used to activate the surface of the anodized film can be appropriately set from, for example, within the range of 1% by mass to 25% by mass. Preferably, the concentration of the acid used to activate the surface of the anodized film is 2% by mass to 20% by mass, and more preferably 2.5% by mass to 15% by mass. The contact time between the anodized film and the acid may be, for example, 10 minutes or less. Preferably, the temperature of the acid used to activate the surface of the anodized film is 10°C to 80°C, and more preferably 20°C to 60°C.

[0042] By X-ray photoelectron spectroscopy, the photoelectron spectrum of the surface of the anodic oxide film is measured after the activation and before contact with the sealing agent. Based on this photoelectron spectrum, the ratio of the concentration of P atoms to the concentration of Al atoms is preferably less than 0.03, more preferably 0.029 or less, and even more preferably 0.028 or less. In this case, the hydration reactivity of the anodic oxide film can be further increased. Therefore, hydrated oxides can be formed more easily on the surface of the anodic oxide film.

[0043] As a sealing agent, for example, a substance capable of reacting with aluminum oxide to form a hydrated oxide can be used, such as hot water or steam at a temperature of 80°C or higher, or an aqueous solution containing ions of one or more metal elements selected from the group consisting of Ni (nickel), Cr (chromium), Zr (zirconium), Si (silicon), Ti (titanium), Au (gold), Ag (silver), Co (cobalt), Mo (molybdenum), Mn (manganese), Nb (niobium), Ta (tantalum), W (tungsten), Zn (zinc), Fe (iron), Ir (iridium), and Sc (scandium). When sealing treatment is performed using hot water or steam, a hydrated oxide layer consisting of aluminum hydrated oxide can be formed on the surface of the anodic oxide film.

[0044] Furthermore, when sealing is performed using an aqueous solution containing ions of the metal element, a hydrated oxide layer containing hydrated aluminum oxide and a salt and / or oxide of the metal element can be formed on the surface of the anodic oxide film. The metal element may exist as a metal ion or as a complex ion in the aqueous solution. More specifically, as a sealing agent containing a metal element, aqueous solutions of metal salts containing the metal element, such as aqueous nickel acetate solution, aqueous cobalt acetate solution, aqueous chromate solution, and aqueous silicate solution, can be used. [Examples]

[0045] An example of the anodized aluminum member and its manufacturing method is described below. As shown in Figure 1, the anodized member 1 of this example has a base material 2 made of aluminum or an aluminum alloy and an anodized film 3 covering the base material 2. The anodized film 3 has a barrier layer 31 provided on the base material 2 and a porous layer 32 provided on the barrier layer 31 and having a plurality of pores 321. The photoelectron spectrum of the surface of the anodized film 3 is measured by X-ray photoelectron spectroscopy, and when the elemental concentrations are calculated based on this photoelectron spectrum, the ratio of the concentration of P atoms to the concentration of Al atoms is 0.03 or more and 0.11 or less.

[0046] The anodized member 1 in this example contains one or more first electrolytes selected from the group consisting of phosphoric acid, diphosphoric acid, triphosphoric acid, and polyphosphoric acid, and one or more second electrolytes selected from the group consisting of inorganic acids other than the acids contained in the first electrolyte, carboxylic acids, and salts thereof. In an electrolytic solution where the concentration of the first electrolyte is 0.1% by mass or more and 3% by mass or less, and the concentration of the second electrolyte is 1% by mass or more and 30% by mass or less, at a current density of 2 mA / cm 2 or more and 150 mA / cm 2 or less, it is obtained by performing an anodizing treatment on the base material 2 under the conditions of a temperature of 0°C or more and 80°C or less.

[0047] Specific examples (test materials A1 to A9) of the anodized member in this example are shown in Tables 1 to 3. The test materials A1 to A10 are obtained, for example, by the following method. First, an aluminum plate having a chemical composition represented by alloy number A5052 is prepared as the base material. This base material is subjected to a pretreatment for anodizing treatment. In the pretreatment, first, the base material is immersed in an aqueous sodium hydroxide solution with a concentration of 5% by mass and a temperature of 55°C for 30 seconds to perform an alkali etching treatment. Then, the base material is immersed in nitric acid with a concentration of 30% by mass and at room temperature for 60 seconds to perform a desmatt treatment.

[0048] After the base material is pretreated as described above, an anodizing treatment is performed by the direct current electrolysis method to form an anodized film on the surface of the base material. The composition of the electrolytic solution used in the anodizing treatment, the temperature, the voltage applied to the base material in the anodizing treatment, the current density, and the treatment time of the anodizing treatment shall be as shown in Table 1. Thus, test materials A1 to A9 can be obtained.

[0049] The anodized film formed in this way is a so-called porous anodic alumina film, which is formed on the base material and is composed of a barrier layer formed on the base material and having no pores, and a porous layer formed on the barrier layer and having a plurality of pores. The thickness of the anodized film in test materials A1 to A9 is within the range of 200 nm or more and 10 μm or less. Also, the thickness of the barrier layer in test materials A1 to A9 is within the range of 10 nm or more and 50 nm or less, and the thickness of the porous layer is within the range of 100 nm or more and 9.9 μm or less.

[0050] Note that test materials B1 and B2 shown in Table 1 are test materials for comparison with test materials A1 to A9. The manufacturing method of test material B1 is the same as that of test material A1, except that an electrolyte solution containing only the second electrolyte and not the first electrolyte was used. The manufacturing method of test material B2 is the same as that of test material A1, except that an electrolyte solution containing only the first electrolyte and not the second electrolyte was used.

[0051] Table 2 shows the concentrations of Al, P, and O atoms calculated based on the photoelectron spectrum of the surface of the anodic oxide film 3. An X-ray photoelectron spectrometer (ULVAC-PHI "PHI 5000 VersaProbe III") can be used to measure the photoelectron spectrum. The concentration of Al atoms is calculated based on the narrow spectrum of the 2p orbital of Al, the concentration of P atoms is calculated based on the narrow spectrum of the 2p orbital of P, and the concentration of O atoms is calculated based on the narrow spectrum of the 1s orbital of O. In Table 2, the "P / Al" column shows the ratio of P atoms to the concentration of Al atoms, and the "(P+Al) / (P+Al+O)" column shows the ratio of the sum of the concentrations of Al atoms and P atoms to the sum of the concentrations of Al atoms, P atoms and O atoms.

[0052] Table 3 shows the moisture stability, surface composition after acid cleaning, and hydration reactivity after acid cleaning for each test material. The evaluation methods are as follows.

[0053] [Stability against moisture] Each test specimen is immersed in boiling water for 60 seconds, then removed from the boiling water and dried. Afterward, the surface of the anodic oxide film is observed using an electron microscope to determine whether the pores in the porous layer are sealed by hydrated oxides. In Table 3, "Good" in the "Stability to Moisture" column indicates that the pores in the porous layer are open and the hydration reaction is suppressed, while "Poor" indicates that the pores in the porous layer are sealed and the hydration reaction has occurred.

[0054] [Surface composition after acid cleaning] The surface of the anodized film is cleaned with oxalic acid by immersing the test material in a 0.3 mol / L oxalic acid aqueous solution for 5 minutes. Next, the oxalic acid adhering to the surface of the anodized film is removed using cold water. Then, the test material is immersed in boiling water for 60 seconds. After removing the test material from the boiling water and drying it, the photoelectron spectrum of the surface of the anodized film is obtained by X-ray photoelectron spectroscopy. Based on the obtained photoelectron spectrum, the concentrations of Al atoms and P atoms on the surface of the anodized film are measured.

[0055] Table 3 shows the concentrations of Al atoms and P atoms on the surface of the anodic oxide film after acid cleaning. The photoelectron spectrum measurement method is the same as that described above for measuring the photoelectron spectrum of the anodic oxide film before acid cleaning. For test materials in which the surface composition of the anodic oxide film after acid cleaning was not measured, the symbol "-" is indicated in the "Surface Composition After Acid Cleaning" column of Table 3.

[0056] [Hydration reactivity after acid washing] The surface of the anodized film is washed with oxalic acid by immersing the test material in a 0.3 mol / L oxalic acid aqueous solution for 5 minutes. Next, the oxalic acid adhering to the surface of the anodized film is removed using cold water. After that, the test material is immersed in boiling water for 60 seconds. After drying the test material removed from the boiling water, the surface of the anodized film is observed using an electron microscope to determine whether or not the pores of the porous layer are sealed by hydrated oxides. In the "Hydration Reactivity After Acid Washing" column of Table 3, "Good" indicates that the pores of the porous layer are sealed by hydrated oxides and that a hydration reaction has occurred, while "Poor" indicates that the pores of the porous layer are open and the hydration reaction has been suppressed. For test materials in which the hydration reactivity after acid washing was not evaluated, the symbol "-" is written in the "Hydration Reactivity After Acid Washing" column of Table 3.

[0057] [Table 1]

[0058] [Table 2]

[0059] [Table 3]

[0060] As shown in Table 1, test materials A1 to A9 were prepared by anodic oxidation treatment of a base material under specific conditions in an electrolyte containing a first electrolyte and a second electrolyte at concentrations within the specified range. As a result, an anodic oxide film comprising a barrier layer and a porous layer is formed on the base material of these test materials. Furthermore, when the elemental concentrations on the surface of the anodic oxide film are calculated based on the photoelectron spectrum obtained by X-ray photoelectron spectroscopy, the ratio of the concentration of P atoms to the concentration of Al atoms is between 0.03 and 0.11.

[0061] As shown in Table 3, test materials A1 to A9, having the above configuration, exhibit excellent stability against moisture and can suppress the formation of hydrated oxides due to unintended hydration reactions with moisture in the atmosphere. Furthermore, the hydration reactivity of test materials A1 to A9 can be improved by activating the anodic oxide film by washing it with acid. Therefore, test materials A1 to A9 can seal the pores of the porous layer at a desired timing.

[0062] In contrast, test material B1 is produced by anodic oxidation in an electrolyte solution that does not contain the primary electrolyte. Therefore, test material B1 has low stability against moisture and is prone to hydration reactions when it comes into contact with moisture in the air.

[0063] Since test material B2 is manufactured by anodic oxidation in an electrolyte that does not contain a secondary electrolyte, a large amount of phosphorus-containing anions tend to remain on the surface of the anodic oxide film after cleaning the anodic oxide film with acid. Therefore, it is difficult to seal the pores of the porous layer of test material B2 at the desired timing.

[0064] Although embodiments of the anodized aluminum member and its manufacturing method have been described above based on the examples, the anodized aluminum member, its manufacturing method, the manufacturing method of the surface-treated aluminum member, and the printed circuit board according to the present invention are not limited to the embodiments described in the examples, and the configuration can be appropriately modified without impairing the spirit of the present invention.

[0065] For example, the anodized aluminum member may take the following forms [1] to [4].

[0066] [1] A base material made of aluminum or an aluminum alloy, The base material has an anodic oxide coating covering it, The anodic oxide film comprises a barrier layer provided on the base material, The barrier layer is provided on the aforementioned barrier layer and comprises a porous layer having a plurality of pores, An anodized aluminum component in which the photoelectron spectrum of the surface of the anodized film is measured by X-ray photoelectron spectroscopy, and the ratio of the concentration of P atoms to the concentration of Al atoms, when the elemental concentrations are calculated based on the photoelectron spectrum, is 0.03 or more and 0.11 or less.

[0067] [2] The anodized aluminum member according to [1], wherein the thickness of the barrier layer is 10 nm or more and 150 nm or less, and the thickness of the porous layer is 100 nm or more. [3] The anodized aluminum member according to [1] or [2], wherein the photoelectron spectrum of the surface of the anodized film is measured by X-ray photoelectron spectroscopy, and the elemental concentrations are calculated based on the photoelectron spectrum, and the ratio of the sum of the concentrations of Al atoms and P atoms to the sum of the concentrations of Al atoms, P atoms and O atoms is 0.280 or more and 0.315 or less. [4] The specific surface area of ​​the anodic oxide film measured by the BET method is 0.1 m² 2 / g or more 10.0m 2 An anodized aluminum component described in any one of [1] to [3], which is less than or equal to / g.

[0068] Furthermore, the method for manufacturing the anodized aluminum member may take the following forms [5] to [7].

[0069] A method for manufacturing an anodized aluminum member as described in any one of [5], [1] to [4], In an electrolyte solution comprising one or more primary electrolytes selected from the group consisting of phosphoric acid, diphosphate, triphosphate, and polyphosphate, and one or more secondary electrolytes selected from the group consisting of inorganic acids other than the acids contained in the primary electrolyte, carboxylic acids, and salts thereof, wherein the concentration of the primary electrolyte is 0.1% by mass or more and 3% by mass or less, and the concentration of the secondary electrolyte is 1% by mass or more and 30% by mass or less, the current density is 2 mA / cm². 2 More than 150mA / cm 2 The following is a method for manufacturing an anodized aluminum member, comprising performing an anodizing treatment on the base material under the conditions of a temperature between 0°C and 80°C. [6] The method for producing an anodized aluminum member according to [5], wherein the first electrolyte is one or more salts selected from the group consisting of phosphates, diphosphates, triphosphates, and polyphosphates. [7] The method for producing an anodized aluminum member according to [6], wherein the first electrolyte is sodium diphosphate.

[0070] Furthermore, the method for manufacturing the surface-treated aluminum member may take the following forms [8] to

[10] . A method for manufacturing a surface-treated aluminum member using an anodized aluminum member described in any one of [8], [1] to [4], The surface of the anodized aluminum member is activated by cleaning it with an acid that does not contain phosphorus atoms. A method for manufacturing a surface-treated aluminum member, wherein the pores in the porous layer are sealed by bringing the anodic oxide film into contact with a sealing agent.

[0071] [9] A method for manufacturing a surface-treated aluminum member according to [8], wherein the photoelectron spectrum of the surface of the anodic oxide film is measured by X-ray photoelectron spectroscopy after the activation and before contact with the sealing agent, and the ratio of the concentration of P atoms to the concentration of Al atoms, when the elemental concentrations are calculated based on the photoelectron spectrum, is less than 0.03.

[10] A method for manufacturing a surface-treated aluminum member according to [8] or [9], wherein, during the activation, the anodized aluminum member is washed with an acid that does not contain phosphorus atoms to dissolve the surface of the anodized film.

[0072] Furthermore, the printed circuit board may take the form described in

[11] below. A printed circuit board containing an anodized aluminum component as described in any one of

[11] , [1], to [4]. [Explanation of Symbols]

[0073] 1. Anodized aluminum component 2 Base material 3. Anodized coating 31 Barrier layer 32 Porous layer 321 pores

Claims

1. A base material made of aluminum or an aluminum alloy, The base material has an anodic oxide coating covering it, The anodic oxide film comprises a barrier layer provided on the base material, The barrier layer is provided on the aforementioned barrier layer and comprises a porous layer having a plurality of pores, An anodized aluminum component in which the ratio of the concentration of P atoms to the concentration of Al atoms, when the photoelectron spectrum of the surface of the anodized film is measured by X-ray photoelectron spectroscopy and the elemental concentrations are calculated based on the photoelectron spectrum, is 0.03 or more and 0.11 or less.

2. The anodized aluminum member according to claim 1, wherein the thickness of the barrier layer is 10 nm or more and 150 nm or less, and the thickness of the porous layer is 100 nm or more.

3. The anodized aluminum member according to claim 1, wherein the photoelectron spectrum of the surface of the anodized film is measured by X-ray photoelectron spectroscopy, and when the elemental concentrations are calculated based on the photoelectron spectrum, the ratio of the sum of the concentrations of Al atoms and P atoms to the sum of the concentrations of Al atoms, P atoms and O atoms is 0.280 or more and 0.315 or less.

4. The specific surface area of ​​the anodic oxide film measured by the BET method is 0.1 m². 2 / g or more 10.0m 2 The anodized aluminum member according to claim 1, wherein the amount is less than or equal to / g.

5. A method for manufacturing an anodized aluminum member according to any one of claims 1 to 4, In an electrolyte solution comprising one or more primary electrolytes selected from the group consisting of phosphoric acid, diphosphate, triphosphate, polyphosphate, and salts thereof, and one or more secondary electrolytes selected from the group consisting of inorganic acids other than the acids contained in the primary electrolyte, carboxylic acids, and salts thereof, wherein the concentration of the primary electrolyte is 0.1% by mass or more and 3% by mass or less, and the concentration of the secondary electrolyte is 1% by mass or more and 30% by mass or less, the current density is 2 mA / cm². 2 150mA / cm or more 2 The following is a method for manufacturing an anodized aluminum member, comprising performing an anodizing treatment on the base material under the conditions of a temperature of 0°C to 80°C.

6. The method for producing an anodized aluminum member according to claim 5, wherein the first electrolyte is one or more salts selected from the group consisting of phosphates, diphosphates, triphosphates, and polyphosphates.

7. The method for producing an anodized aluminum member according to claim 6, wherein the first electrolyte is sodium diphosphate.

8. A method for manufacturing a surface-treated aluminum member using an anodized aluminum member according to any one of claims 1 to 4, The surface of the anodized aluminum member is activated by cleaning it with an acid that does not contain phosphorus atoms. A method for manufacturing a surface-treated aluminum member, wherein the pores in the porous layer are sealed by bringing the anodic oxide film into contact with a sealing agent.

9. A method for manufacturing a surface-treated aluminum member according to claim 8, wherein the photoelectron spectrum of the surface of the anodic oxide film is measured by X-ray photoelectron spectroscopy after the activation and before contact with the sealing agent, and the ratio of the concentration of P atoms to the concentration of Al atoms, when the elemental concentrations are calculated based on the photoelectron spectrum, is less than 0.

03.

10. The method for manufacturing a surface-treated aluminum member according to claim 8, wherein, during the activation, the anodized aluminum member is washed with an acid that does not contain phosphorus atoms to dissolve the surface of the anodized film.

11. A printed circuit board comprising an anodized aluminum member according to any one of claims 1 to 4.

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