JPS6031217A - Aluminum foil for electrolytic condenser electrode and method of producing aluminum electrode for electrolytic condenser - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aluminum foil for electrolytic capacitor electrodes and a method for manufacturing aluminum electrodes for electrolytic capacitors.

When electrodes for stain-resolving capacitors are manufactured by electrolytically etching aluminum foil (hereinafter referred to as Al), two types of electrodes are obtained: the so-called "penetration type" and the "Omochi 9 type." The majority of the former are bits that almost reach from one side of the Al foil to the other side or completely penetrate the cross section of the Al foil. This is because although the capacitance is high, the bending strength is low, so when winding up the electrode foil as a capacitor element, there is an open circuit that occurs when the foil breaks.
In order to avoid this, there is a drawback that the capacity cannot be further increased. The latter can be achieved by adjusting the electrolytic etching conditions (temperature, time, current density, etc.).jl) The presence of a bit of about 10 to 20% of the foil thickness near the center of the AJ foil cross section1. The "core" part remains. Although this "Omochibashi type" has a higher bending strength than the "penetrating type", it has the disadvantage that 88 is low when used as a capacitor, and it also has a so-called double anode that uses two sheets stacked on top of each other. It cannot be used for any purpose. this is,
This is because the electrolytic solution does not penetrate into the eastern portion, so ion conduction to the cathode does not occur.

The present invention provides an A/electrode for an electrolytic capacitor that has excellent bending strength, provides a large capacity to the capacitor, and can be used as a double anode.That is, the present invention provides an A/electrode for an electrolytic capacitor that has a purity of 99. Apply alkali-removable resist ink to one or both sides of 9% or more AA' foil mrp O
, 1 to 5 mm, and a line spacing of 0.5 to 10 mm, with an area ratio of 3 to 2 (l). (referred to as invention), and (2) forming a multi-line pattern of 3 to 20 lines with an alkali-removable resist ink on one or both sides of i-foil with a purity of 99.996 or higher with a line width of o, t~6 mm, and a line spacing of 0.5~10 mm. % area ratio, electrolytically etched, removed with a resist ink, washed with alkali, and further chemically treated as required (hereinafter referred to as the present application) (referred to as the second invention).

Electrolytic capacitor t [i-user! The foil is
For example, KL'r is manufactured as follows. That is, 99.91
A pattern consisting of a large number of lines is formed on a portion of one or both sides of the foil using a resist ink that is resistant to electrolytic etching solution and can be removed by alkaline solution. The line width, line spacing, etc. of the resist ink will vary depending on the electrode foil's °C dimensions, thickness, capacitor capacity, etc., but it is usually 0.1 to 5mf11% line spacing 0.5 in the line.
It is about 10 mm. The linear application portion of the resist ink forming the pattern may be formed in the short direction or diagonal direction of the foil, but it is desirable to form it parallel to the longitudinal direction of the Al foil. This is because the unetched portion is formed along the winding direction of the electrode foil. FIG. 1 shows a partially enlarged sectional view of an example of the A7 foil of the first invention of the present application. In Figure 1, rtA) Both sides of the foil ill are coated with resist ink to form line groups +31, 131... (
3) and line 1i +51, +51...(5
) is formed. When coating both sides of the Resinutoingi kAl foil ([), it is desirable to provide the lines 131 on the front and back sides in the same position as possible (5). This is because when AJ foil 1 [) is electrolytically etched,
Line group iA), 13)...(3) and line group 15+
, 15+...-5), no bits are formed at all in the Al foil portion, and this portion greatly contributes to improving the bending strength. Application of resist ink is
3-20'% of the total ffi+product on one or both sides in AI foil
shall be. Considering the balance between capacity and folding strength, 5
It is more preferable to set it to 10%. If the coating area is less than 3 mm, the folding strength will not be improved sufficiently, while if it exceeds 20 mm, the capacitance of the capacitor will be reduced.

As a resist ink, modified pheno-7 has excellent resistance (acid resistance) and voltage resistance during electrolytic etching, and can be easily removed with an aqueous alkaline solution such as an aqueous NaOH solution.
resin, modified alkyd resin, acrylic resin, etc. are used. Resist Ink Co., 8 μm or more, preferably 10
It is preferable to apply by an intaglio printing method, a silk screen method, etc., which allows thick coating of μm or more, and after application, it is cured by ultraviolet rays, heating, etc. according to a conventional method.

The first invention of the present application is carried out as follows.

For example, kl m i) of the structure shown in FIG.
.

Through-hole bits +7+, +7+ (7) are formed by dipping in a known etching solution containing Nap/etc., and performing electrolytic etching according to a conventional method. In this case, line group 131, +31...1
In the area +91, +91...(9) between 3) and the line group +51, +51...(5),
No bits are formed. Then All after etching
By immersing the ll in an alkali solution such as NaOH or [)H, the resist ink line groups 131, +31,
...[41 and +51, +51...]
(5) Completely dissolved and removed, and further washed to obtain an electrolytic capacitor A/electrode uD as shown in FIG. 3 (C1). Electrode CIl
+ is used as an anode (if used, further chemical conversion treatment is performed).

In addition, as an Al electrode for an electrolytic capacitor, as shown in Fig. 3 (I
3) It is also possible to cut out and use only the part shown in C.

According to the present invention, the following effects can be obtained.

(1) Although the t[[i obtained after etching is of the so-called 'penetration type', it has excellent % folding strength.

(ll) Therefore, since the curvature during winding can be increased, it is possible to downsize the capacitor.

(lit) The capacitance when used as a capacitor is of course limited, but the use of double node foil and C is also Example 1 +aJ Al annealed foil (thickness 100 μm, 99°99%)
After applying resist ink in a linear manner in the longitudinal direction on both sides using a 300 mesh screen,
It was dried and cured at ℃ for 5 minutes.

The resist ink used was acrylic resin/butyl cellosolve/carbon black near 2/25/3 (weight ratio), and the line width was t o um.

The line spacing is 1 mm, the thickness is 9 μm, and the coating area ratio is 10
It was Chi.

The obtained coated AA' foil was immersed in a 4.5% hydrochloric acid aqueous solution,
After performing electrolytic etching for 6 minutes at a temperature of 80°C and a DC current density of L 5 A/dm2, the cured resist ink was removed by immersion in a 0.2% Fium hydroxide aqueous solution for 5 seconds at room temperature. . Next, the foil was washed with water and dried, and then subjected to a chemical conversion treatment of 380 μm in a 5% ammonium borate aqueous solution. The performance of the obtained electrode foil was as shown in Table 1.

Table 1 The folding strength in Table 1 is determined by cutting the unformed foil after etching in parallel to the longitudinal direction into a width of l Q l11m, and pulling the lower part of the cut foil with a force of 250F. Two rows /L/(t,.

mmR), and using this as a fulcrum, move the upper part of the foil from side to side 4
The number of times the foil was bent 5 degrees and reciprocated until it was cut was measured.

Further, the capacitance was measured by a known bridge method. Conventional products refer to conventional through-hole types.

lb) The same operation as above (except that the etching time was changed to 8 minutes) was carried out. The results are as shown in Table 2.

Table 2 As is clear from Table 2, in the product of this example, the capacity improved significantly due to the increase in the amount of electricity, and the bending strength did not decrease much. On the other hand, with conventional products, the improvement in capacity is small and the folding strength is greatly reduced.

(Even when the C1 resist ink was applied only to one side of A4 foil and when the application positions on both sides were not the same, it was confirmed that the effect was superior to that of the conventional product.

(dJ When 1 drop of ethylene glycol-y was added to the surface of the above-mentioned products (a) and (b) of the present invention, and the time taken for ethylene glycol to penetrate into the back surface was measured, results equivalent to those of the 49 conventional products listed below were obtained. Ta.

Conventional product [6 minutes etching] 4.5 seconds Invention product (Kawa [6 minutes etching] 5.0 seconds Invention product (
To) [8 minutes etching] 4.0 seconds

[Brief explanation of the drawing]

FIG. 1 shows a partially enlarged sectional view of an AI foil according to the first invention of the present application, and FIGS. 2 and 3 are drawings showing the state of implementation of the second invention of the present application. 1[)...Al foil, (3) and (5)...Resist ink application area, (7)
...through bit, (9)...area where no bit is formed, aIJ...
AI for electrolytic capacitors! electrode. (And more) 1・1:...Tono C1,4 Otsu'j'1. ', + ni 2, Shikyu shi) Figure 1 Figure 2 Figure 3 Figure 3 Procedural Amendment C'j5 Section 1. Case Description 1981 Patent Application No. 1061 2 Title of Invention Electrolytic Condan 1J Aluminum Foil for Electrode and Method for Manufacturing Aluminum Electrode for Electrolytic Capacitor 3, Person Making Amendment Relationship with Case Patent Applicant 4, Agent 10 Sawa no Tsuru Building, 2 Hiranocho, Higashi Ward, Osaka City Telephone 06-203
-0941 (Representative) Contents of correction on November 29, 1982! Figures 1, 2, and 3 are corrected as shown in the attached sheet. (that's all)

Claims (1)

[Claims] ■ Alkali-removable resist ink is applied to one or both sides of an aluminum foil with a purity of 99.9'% or more.
1. An aluminum foil for an electrolytic capacitor electrode, characterized in that a shaped pattern is formed by coating at an area ratio of 3 to 20'%. ■ Apply alkali-removable resist ink to one or both sides of aluminum foil with a purity of 99.9% or higher to a line width of 0.
After coating and forming a multi-linear pattern with a line spacing of 1 to 5111 m% at an area ratio of 3 to 20% and electrolytically etching, the resist ink is removed with alkali, washed, and further chemical conversion treatment is performed as necessary. A method for manufacturing an aluminum electrode for an electrolytic capacitor, characterized by: