JP2009081343A - Aluminum foil material for vapor deposition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aluminum foil material for vapor deposition capable of securing high adhesiveness between a base and a vapor-deposited layer. <P>SOLUTION: Disclosed is the aluminum foil material for vapor deposition which is 10 to 50 μm thickness, the aluminum foil material for vapor deposition being characterized in 0.1 μm≤Ra and Rsm≤18.0 μm, where Ra is surface roughness measured in a direction perpendicular to the rolling direction of the foil material and RSm is an average peak interval. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an aluminum foil material for vapor deposition, and more particularly to an aluminum foil material for vapor deposition that is used in the case of depositing aluminum or the like as an electrode base material for an electrode such as an electrolytic capacitor.

  With the miniaturization of electronic components, there is a demand for an improvement in the capacitance of aluminum foils for electrolytic capacitors that are incorporated into electronic components. For this reason, many attempts have been made to increase the surface area of aluminum foil for electrolytic capacitor electrodes. Has been made.

Among them, as a method for dramatically increasing the surface area of aluminum foil, aluminum foil for electrodes that can obtain a high electrostatic capacity by vapor-depositing valve metal such as aluminum on an aluminum foil base material. A material has been proposed (see Patent Document 1). There has also been proposed an electrode in which the porosity, specific surface area, and particle diameter of the deposited aluminum particle layer are defined (see Patent Document 2), and is an aluminum foil for an electrode for forming a metal thin film on a substrate, the surface roughness of the substrate. There has also been proposed an electrode foil for an electrolytic capacitor in which (RMS) is set to 0.003 to 0.2 μm and a decrease due to a change in capacitance after manufacture is suppressed (see Patent Document 3).
JP-A-11-317331 JP 2007-123814 A JP-A-4-61312

  However, if an aluminum foil material having a thickness of 10 to 50 μm is used as a base material for vapor deposition, sufficient adhesion with the vapor deposition layer cannot be obtained, and it is based on winding up as an electrode of an electrolytic capacitor. There is a problem that the deposited layer peels off from the material.

  In order to improve the adhesion between the aluminum foil material as the deposition base material and the deposition layer, the inventors focused on the surface state of the aluminum foil material, and as a result of testing and examination, It was found that control of the surface roughness (Ra) and the average peak distance (RSm) in the specific method is important for improving the adhesion.

  The present invention was made as a result of further testing and examination based on the above knowledge, and the purpose thereof is an aluminum foil material for vapor deposition that can ensure high adhesion between the substrate and the vapor deposition layer. Is to provide.

The aluminum foil material for vapor deposition according to claim 1 for achieving the above object is an aluminum foil material having a thickness of 10 to 50 μm, and the surface roughness (Ra) measured in a direction perpendicular to the rolling direction of the foil material. ) Is 0.1 μm ≦ Ra, and the average crest distance (RSm) measured in the direction perpendicular to the rolling direction of the foil material is RSm ≦ 18.0 μm.

  According to the present invention, since predetermined surface shape control is performed on the aluminum foil material, when the valve metal particle layer having an oxide film on the surface is formed by vapor deposition, high adhesion between the base material and the vapor deposition layer is ensured. An aluminum foil material for vapor deposition that can be provided is provided.

  The aluminum foil material for vapor deposition of the present invention is an aluminum foil material having a thickness of 10 to 50 μm, the surface roughness measured in the direction perpendicular to the rolling direction of the foil material is 0.1 μm ≦ Ra, and the average crest interval is RSm ≦ 18.0 μm.

  If the surface roughness Ra measured in the direction perpendicular to the rolling direction is less than 0.1 μm, a sufficient anchor effect cannot be obtained, and the adhesion between the substrate and the vapor deposition layer decreases. If the surface roughness Ra measured in the direction perpendicular to the rolling direction becomes too large, the surface irregularities become large and the uniformity of vapor deposition is hindered. Therefore, 0.1 μm ≦ Ra ≦ 0.6 μm is preferable. 0.15 μm ≦ Ra ≦ 0.4 μm is more preferable, and 0.2 μm <Ra ≦ 0.4 μm is further preferable.

  When the average peak distance RSm measured in the direction perpendicular to the rolling direction exceeds 18.0 μm, a sufficient anchor effect cannot be obtained, and the adhesion between the base material and the vapor deposition layer decreases. A more preferable range of the average mountain interval RSm measured in the direction perpendicular to the rolling direction is RSm ≦ 16.0 μm.

  The aluminum foil material according to the present invention is manufactured through chamfering, hot rolling, and cold rolling of an ingot, but in order to obtain the surface roughness Ra and the mountain spacing RSm of the present invention, the surface shape of the roll surface is used. The method of performing cold rolling using the rolling roll which prepared this can be used.

  Examples of the present invention will be described below in comparison with comparative examples to demonstrate the effects of the present invention. These examples show one embodiment of the present invention, and the present invention is not limited thereto.

Examples and Comparative Examples Using an aluminum ingot with an aluminum purity of 99.85%, in accordance with a conventional method, after melting, casting, facing, hot rolling, cold using a rolling roll whose surface shape was adjusted. Rolling was performed to produce an aluminum foil having a thickness of 30 μm. The obtained aluminum foil was used as a test material, and for each test material, the surface roughness Ra in the direction perpendicular to the rolling direction and the average mountain spacing RSm were measured and subjected to the following adhesion evaluation test.

Adhesion evaluation test: For the purpose of evaluating the adhesion between the base material and the vapor deposition layer, the aluminum foil thus obtained was subjected to 3 × 10 ⁻³ torr of nitrogen and 3 × using aluminum of 99.8% aluminum as a vapor deposition source A 20 μm-thick aluminum vapor deposition layer is formed by resistance heating vapor deposition in an atmosphere with 10 ⁻⁴ torr oxygen, and then a tape peeling test according to JIS H8504 is performed. The adhesion was evaluated as “Good”, and “Good” was evaluated as “Good”, and “Good” was evaluated as “Poor”. Table 1 shows the results of the adhesion evaluation test. In Table 1, those outside the conditions of the present invention are underlined.
In addition, the said vapor deposition method is the method described in the Example of the paragraph 0025 of the said patent document 1, ie, nitrogen of the pressure of 0.002 torr-0.005 torr, and 2 * 10 < ^-4 > torr * 5 * 10 < ^- >. It was based on vapor deposition by heat resistance vapor deposition on an aluminum foil maintained at a temperature of 300 ° C. in an anhydrous atmosphere with oxygen at a pressure of ⁴ Torr.

As shown in Table 1, all of the test materials 1 to 3 according to the present invention had good adhesion.
On the other hand, since the test material 4 had a surface roughness Ra measured in a direction perpendicular to the rolling direction of less than 0.1 μm, a sufficient anchor effect was not obtained and the adhesion was inferior. Since the average crest distance RSm measured in the direction perpendicular to the rolling direction of the test material 5 exceeded 18.0 μm, a sufficient anchor effect was not obtained and the adhesion was inferior.

Claims (1)

10 to 50 μm thick aluminum (including aluminum alloy, the same applies hereinafter) foil material, the surface roughness (Ra) measured in the direction perpendicular to the rolling direction of the foil material is 0.1 μm ≦ Ra, and An aluminum foil material for vapor deposition, wherein an average peak interval (RSm) is RSm ≦ 18.0 μm.