JP2001129923A - Polyamide resin laminated metal panel and manufacturing method of exterior container for electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin film laminated metal panel hard to generate the interfacial peeling of a resin film and a metal panel at a time of drawing processing or caulking processing and hard to generate yellowing even if exposed to high temperature and to produce an exterior container for an electrolytic capacitor having excellent insulating properties and high quality from this resin film laminated metal panel. SOLUTION: In a resin laminated metal panel wherein a multilayered polyamide film is laminated to the single surface of an aluminum panel, the multilayered polyamide film is a two-layered film consisting of a layer (A) comprising a mixture consisting of 50-95 weight % of amorphous polyamide and 50-5 weight % of aliphatic polyamide and a layer (B) comprising only aliphatic polyamide and the total thickness thereof is set to 5-50 μm and the two-layered film satisfying [ thickness of layer (B)}/(total thickness of two- layered film)]<=0.3 is laminated so that the aromatic polyamide layer becomes outside. An exterior container for an electrolytic capacitor is produced from the resin film laminated metal panel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing a laminated metal sheet of a polyamide resin and an outer container for an electrolytic capacitor. More specifically, the present invention relates to a polyamide-based resin-laminated metal sheet suitable for manufacturing an outer container for an aluminum electrolytic capacitor used in an electronic device, and a method for manufacturing an outer container for an aluminum electrolytic capacitor.

[0002]

2. Description of the Related Art Conventionally, as an external container for accommodating a capacitor element constituting an aluminum electrolytic capacitor, a cylindrical container formed by drawing a thin aluminum plate was usually used. On the outer peripheral surface of the cylindrical container, a film such as a vinyl chloride resin or an olefin resin is laminated for the purpose of electric insulation and display of contents.

In recent years, electronic components have been miniaturized, and aluminum electrolytic capacitors have also been miniaturized.
Further, a chip type electrolytic capacitor without a lead wire for surface mounting has been developed. In such an aluminum electrolytic capacitor, particularly in the chip type electrolytic capacitor, since it is extremely difficult to coat the surface of the outer container, heat resistance, a polyamide resin having excellent solvent resistance,
In particular, an aluminum sheet laminated with polyamide 6 or polyamide 66 has come to be used as an exterior container (for example, JP-A-1-75222, JP-A-3-7222).
9974).

[0004] When manufacturing an outer container for an electrolytic capacitor from an aluminum plate on which a resin film is laminated, the outer container is processed by a cold drawing method, so that most of the laminated resin is selected from resins having good extensibility and elongation. However, it is still easy to cause plastic deformation due to processing stress, and the adhesion strength at the interface between the aluminum plate surface and the resin film layer decreases,
Pinholes, voids, microcracks, etc. may occur in the film, or the film may peel off. This phenomenon tends to be further magnified by secondary processing stress when the capacitor element is housed in the outer container and the open end of the outer container is sealed with an elastic sealing member such as rubber.

[0005] In order to improve the abnormalities and peeling of the film due to a decrease in the adhesion strength of the interface in the above-mentioned cold drawing step and the subsequent post-processing step, a method of performing heat treatment after preparing an outer container is provided. A special device for that purpose has been proposed (see, for example, JP-A-1-66030 and JP-A-2-18043). According to these proposed methods, the outer container obtained by cold drawing is heat-treated at a temperature equal to or higher than the melting point of the laminated resin film, and pinholes, voids of the resin film generated at the time of cold drawing,
It can be said to be a useful method because it can repair microcracks and the like and at the same time restore the adhesion strength at the interface.

However, according to the above-mentioned method, the heat treatment is performed at a temperature higher than the melting point of the laminated resin film after the outer container is formed. However, it requires a large amount of heat, which is economically disadvantageous. Furthermore, thermal degradation is apt to occur during the solder reflow process, and the processing temperature tends to increase particularly as the lead-free solder is used. Improvement in yellowing during high-temperature processing has been desired. As a method for improving yellowing during high-temperature treatment, there is a method of adding a phenolic antioxidant, a phosphorus-based processing stabilizer, or the like to polyamide 6 or polyamide 66. However, a considerable amount of such an additive is added. However, no substantial yellowing improvement effect was observed.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made to solve such problems, and pinholes, voids, microcracks, and peeling are less likely to occur in a resin film by cold drawing. As a result of intensive studies to provide a method of manufacturing a polyamide resin laminated thin plate which is not easily yellowed even when exposed to a high temperature in a heat treatment step or a solder reflow step, and an outer container for electronic parts of excellent quality, It was completed.

The objects of the present invention are as follows. 1. Provided is a polyamide-based resin-laminated metal plate that is less likely to generate pinholes, voids, and microcracks in a resin film by cold drawing, and can repair them with a small amount of heat even if it occurs. 2. To provide a polyamide-based resin laminated thin plate that is not easily yellowed even when exposed to high temperatures. 3. An object of the present invention is to provide a method for producing a high-quality external container for electrolytic capacitors, which is made of the above-mentioned polyamide-based resin-laminated metal plate and is excellent in appearance, insulation and the like.

[0009]

According to a first aspect of the present invention, there is provided a metal plate in which a multilayer film made of a polyamide resin is laminated on one side of an aluminum plate. Crystalline polyamide resin 5
A film having a two-layer structure of a layer (A) composed of a mixture of 0 to 95% by weight and an aliphatic polyamide resin of 50 to 5% by weight, and a layer (B) composed of only an aliphatic polyamide resin,
The total thickness of the two-layer film is set to 5 to 50 μm, and the two-layer film has a thickness of {{(B) layer thickness}}.
/ (Total thickness of the two-layer film)] ≦ 0.3, and a laminated metal sheet of polyamide resin characterized by being laminated with the (A) layer outside.

In the second invention of the present invention, when manufacturing an outer container for an electrolytic capacitor from a metal plate in which a multilayer film made of a polyamide resin is laminated on one surface of an aluminum plate, the multilayer film is made of an amorphous polyamide resin. 50
~ 95% by weight and aliphatic polyamide resin 50 ~ 5% by weight
(A) layer composed of a mixture of the above and a (B) layer composed only of an aliphatic polyamide resin, and the total thickness of the two-layer film is 5 to 50 μm.
Moreover, this two-layer film has a thickness of {{(B) layer thickness} /
(The total thickness of the two-layer film)] ≦ 0.3, and is laminated with the (A) layer on the outside.
Provided is a method for producing an outer container for an electrolytic capacitor, characterized in that a cylindrical container with a bottom is formed by drawing with the two-layer film outside.

According to a third aspect of the present invention, in a metal plate in which a multi-layer film made of a polyamide resin is laminated on one side of an aluminum plate, the multi-layer film comprises 50 to 95% by weight of an amorphous polyamide resin, Polyamide resin 50
(A) layer composed of a mixture of the (B) layer and the (B) layer composed only of an aliphatic polyamide resin.
The (A) layer / (B) layer is laminated in this order to form a three-layer film, the total thickness of the three-layer film is 5 to 50 μm, and the three-layer film is [｛( B) Thickness of layer｝ / (total thickness of three-layer film)] ≦ 0.3.

According to a fourth aspect of the present invention, in manufacturing an outer container for an electrolytic capacitor from a metal plate in which a multilayer film made of a polyamide resin is laminated on one surface of an aluminum plate, the multilayer film is made of an amorphous polyamide resin. 50
~ 95% by weight and aliphatic polyamide resin 50 ~ 5% by weight
(A) layer composed of a mixture of the above and a layer (B) composed only of an aliphatic polyamide are laminated in the order of (B) layer / (A) layer / (B) layer to form a three-layer film. The total thickness of the three-layer film is 5 to 50 μm, and
This three-layer film satisfies the relationship of [{thickness of the (B) layer} / (total thickness of the three-layer film)] ≦ 0.3. Provided is a method for manufacturing an outer container for an electrolytic capacitor, which is characterized by forming a bottomed cylindrical container.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The metal in the polyamide-based resin-laminated metal plate according to the present invention is aluminum and has a purity of 90% or more, and a thin plate having a thickness of 0.2 to 0.6 mm is preferable. This aluminum thin plate may be one whose surface has been subjected to a chemical conversion treatment with phosphoric acid-chromic acid or the like or an etching treatment such as electrolytic etching.

The polyamide resin laminated metal sheet according to the present invention is obtained by laminating a multilayer film made of a polyamide resin on one surface of the metal plate. The polyamide resin constituting the multilayer film is a film composed of a mixture of an amorphous polyamide resin and an aliphatic polyamide resin (hereinafter referred to as a layer (A)), and a film composed of only an aliphatic polyamide resin. , Which is referred to as a layer (B), is a film laminated in a plurality of layers.

In the present invention, the amorphous polyamide resin means a resin which does not crystallize or hardly crystallizes when molded. In general, a polymer having a side chain that inhibits crystallization, a ring structure, or a polymer composed of a monomer component having a ring structure is exemplified. Amorphous polyamide resin films are less likely to yellow at high temperatures, but have poor adhesion to the metal surface, draw the film laminated metal plate, peel off the laminated film in the caulking process after drawing, Alternatively, the laminated film may be peeled off in the washing step after drawing.

The amorphous polyamide resin is obtained by reacting a dicarboxylic acid such as terephthalic acid or isophthalic acid with a diamine such as hexamethylenediamine 4,4'-diamino-dicyclohexylenepropane or isophoronediamine. Polyamides and polyamides obtained by further copolymerizing a lactam component and an isocyanate component such as 4,4′-diphenylmethane diisocyanate with the above components are exemplified. In the market, "Crivory XE3038" (trade name) manufactured by EMS, "Sealer PA3426" (trade name) manufactured by Mitsui Dupont Polychemicals,
"Novamid X21" (trade name) manufactured by Mitsubishi Engineering-Plastics Corporation is available.

In the present invention, the aliphatic polyamide resin includes polyamide 6 obtained by ring-opening polymerization of ε-caprolactam, polyamide 66 obtained by condensation polymerization of hexamethylenediamine and adipic acid, and condensation polymerization of 11-aminoundecanoic acid. The resulting polyamide 11,
Polyamide 12 obtained by ring-opening polymerization of ω-laurolactam or polycondensation of 12-aminododecanoic acid. Among them, polyamide 6 is preferable. Aliphatic polyamide resin is inferior to amorphous polyamide resin in heat resistance, and when exposed to high temperatures such as in a solder reflow process,
It has a tendency to yellow, but has better adhesion to metal surfaces than amorphous polyamide resins.

The layer (A) composed of a mixture of the amorphous polyamide resin and the aliphatic polyamide resin comprises 50 to 95% by weight of the amorphous polyamide resin and 50 to 95% by weight of the aliphatic polyamide resin.
5% by weight. If both are mixed in this range, the advantages of each other can be utilized and the disadvantages can be compensated. The proportion of the aliphatic polyamide resin in the mixture is 50
If the content is more than 10% by weight, yellowing tends to be conspicuous when exposed to a high temperature in a solder reflow step or the like, which is not preferable.

The details of the mechanism of thermal degradation of the polyamide resin are unknown, but it is said that the generated peroxy radicals attack hydrogen atoms, and further proceed to oxidation (addition of O 2) reaction and hydrogen addition. . It is believed that chromophores are formed and yellowed during such thermal degradation. The reason why amorphous polyamide resin has no particular melting point and is difficult to yellow at high temperatures is unknown, but it is presumed that the formation of peroxy radicals and chromophores is suppressed because it has an aromatic group in the molecular chain. You.

In the first invention and the second invention of the present invention, the multilayer film comprises the (A) layer and the (B) layer,
(A) It is laminated on a thin aluminum plate with the layer outside. When the (A) layer is on the outside, yellowing resistance is excellent, so that yellowing can be significantly suppressed. Further, when the layer (B) is laminated on the surface of the aluminum sheet, the adhesive strength at the interface between the aluminum sheet and the layer (B) is excellent, and pinholes, voids, and microcracks are generated in the resin film during low-temperature drawing. It is difficult to obtain an outer container excellent in quality without lowering the insulation of the product.

The resin mixture for forming the layer (A) and the aliphatic polyamide resin for forming the layer (B) may be, if necessary,
Various resin additives can be blended. Examples of the resin additives include coloring agents such as dyes and pigments, lubricants, antiblocking agents, heat stabilizers, light stabilizers, and impact modifiers. These resin additives can be blended in amounts that do not adversely affect the properties of the (A) layer film.

The polyamide resin laminated metal sheet according to the present invention is formed by laminating a two-layer film having a total thickness of 5 to 50 μm on the surface of an aluminum thin plate. If the total thickness of the two-layer film is less than 5 μm, it is too thin, so that the production of the two-layer film and the laminating operation on the surface of the aluminum thin plate become difficult. In this case, not only is the film easily peeled off, but it is economically disadvantageous, and both are not preferred. The preferred range of the total thickness of the two-layer film is 15 to 3
0 μm.

In the polyamide-based resin-laminated metal sheet according to the present invention, the thickness of the (A) layer and the (B) layer constituting the two-layer film is [{(B) layer thickness} / (2) (Total thickness of layer film)] (hereinafter, the value obtained based on this formula is abbreviated as “thickness ratio 2”) ≦ 0.3. If the thickness ratio is more than 0.3, it is not preferable because yellowing tends to occur when exposed to high temperatures. The lower limit of the thickness ratio 2 is not particularly limited, but when the thickness of the (B) layer is extremely thin, it becomes difficult to form a film, for example, when compounding a resin additive, it is necessary to increase the compounding amount. Therefore, it is preferably 0.01 or more.

To produce the above two-layer film, (1)
(A) Layer and layer (B) are separately produced and laminated by heat bonding or an adhesive. (2) Two types of amide resins are melted by separate extruders and co-extruded. A method of manufacturing by a co-extrusion method of extruding into two layers by laminating in a die,
And the like.

The polyamide resin film can be produced by a conventionally known method such as an extrusion molding method using a coat hanger die, a T die, an I die, an inflation die and the like, a calender molding method, and the like. May be unstretched or biaxially stretched. The two-layer composite film may be subjected to a corona discharge treatment, a flame treatment, or the like for the purpose of improving the affinity with the adhesive for the surface of the layer (B) made of the aliphatic polyamide resin adhered to the aluminum thin plate. .

In order to manufacture the polyamide resin laminated metal sheet according to the present invention, (1) an adhesive is applied to the surface of an aluminum thin plate, a previously prepared two-layer film is superimposed on the coated surface, and a heated nip roll And (2) a method in which a previously prepared and heated two-layer film is superimposed on a heated aluminum thin plate, and thermocompression-bonded by a heated nip roll to laminate.

In the third and fourth inventions of the present invention, the multilayer film is composed of (A) layer and (B) layer,
The (A) layer is an intermediate layer, the (B) layer is laminated on both sides of the (A) layer to form a three-layer film, and one of the (B) layers is laminated on a thin aluminum plate. The total thickness of the three-layer film is 2
It should be selected in the range of 5 to 50 μm as in the case of the layer film. The reason for setting the total thickness in this range is the same as that described for the two-layer composite film.

The layer (A) and the layer (A) constituting the three-layer film
The layer is defined as [{(B) layer thickness} / (total thickness of three-layer film)] (hereinafter, a value obtained based on this formula is abbreviated as “thickness ratio 3”) ≦ 0. 3. It is necessary to satisfy the following relationship. When the thickness ratio is more than 0.3, yellowing tends to occur when exposed to a high temperature, which is not preferable. The lower limit of the thickness ratio 3 is not particularly limited, but when the thickness of the layer (B) is extremely thin, it becomes difficult to form a film, for example, when compounding a resin additive, it is necessary to increase the compounding amount. Therefore, it is preferably 0.01 or more.

To produce the three-layer film, (3)
(A) Layer and layer (B) are separately produced and laminated by heat bonding or an adhesive. (4) Two types of polyamide resins are melted by separate extruders and co-extruded. A co-extrusion method of laminating in a die or an adapter having a special structure, or in a co-extrusion die, and extruding into three layers. The production of the polyamide resin film and the surface treatment of the surface of the layer (B) made of the aliphatic polyamide resin adhered to the aluminum thin plate are the same as in the case of the two-layer composite film. 3 on aluminum sheet
The method of laminating the layer films is the same as in the case of the two-layer film.

A two-layer film or 3 on an aluminum thin plate
To manufacture a bottomed outer container from a polyamide-based resin-laminated metal plate on which a layer film is laminated, the multilayer film surface is set to the outside, and a cold-drawing process is performed to form a bottomed outer container. The outer container is heat-treated in a temperature range in which the lower limit temperature is the glass transition temperature of the amorphous polyamide resin and the upper limit temperature is the melting point of the aliphatic polyamide resin plus a temperature of 50 ° C.

By performing the heat treatment in the above temperature range, the layer (B) of the bottomed outer container manufactured by the cold drawing method is melted, and the adhesion between the multilayer film and the aluminum thin plate is restored. , Pinholes, voids, micro cracks, etc. can be repaired. If the heat treatment temperature is lower than the lower limit temperature, the recovery of the adhesion strength at the interface between the multilayer film surface and the aluminum thin plate is not sufficient. If the heat treatment temperature exceeds the upper limit temperature, it is not preferable from the viewpoint of heat deterioration of the multilayer film and heat treatment cost. Here, the melting point of the aliphatic polyamide resin is a differential scanning calorimeter (DSC)
And the absorption peak temperature that appears when the temperature is raised at a rate of 10 ° C./min.

Hereinafter, the present invention will be described in more detail with reference to the drawings and test examples, but the present invention is not limited to the following description unless it departs from the gist.

FIG. 1 is a sectional view of an example of a polyamide resin laminated metal plate according to the first invention of the present invention, and FIG. 2 is a sectional view of an example of a polyamide resin laminated metal plate according to the third invention of the present invention. It is. In the figure, 1 is an aluminum thin plate, 2
Is a two-layer film, 3 is a three-layer film, 4 is an (A) layer made of a mixture of polyamide-based resins, and 5 is a (B) layer made of only an aliphatic polyamide resin.

[Test Examples 1 to 6] <Preparation of Two-Layer Film> Among the polyamide resins, "Novamid X21" (trade name) manufactured by Mitsubishi Engineering-Plastics Corporation (glass transition point = 124 ° C.), “Novamid X1030” (trade name) manufactured by the company as an aliphatic polyamide resin (melting point = 223)
° C) as a raw material, and the two were mixed at the ratio shown in Table 1 to obtain a mixture for forming an (A) layer. (A) The mixture for forming a layer and the aliphatic polyamide resin for forming a layer (B) are separately melt-kneaded using two extruders equipped with a T-die, and biaxially stretched films having different thicknesses. Were produced in multiple types. By combining two types of films having different thicknesses, six types of two-layer films having different total thicknesses and “thickness ratio 2” ratios as shown in Table 1 were prepared.

<Preparation of a two-layer film laminated metal plate> An aluminum plate (1100P-H18) having a thickness of 0.30 mm was prepared by adding phosphoric acid
Chemical conversion treatment with chromate treatment solution, thickness 20mmg / m ²
Was formed. After applying an epoxy-based adhesive to the chemical conversion-treated surface to a thickness of 1.4 μm, a two-layer film having a total thickness and a thickness ratio of 2 as shown in Table 1 was overlaid. By pressing with a heated nip roll, six types of film-laminated metal plates were prepared.

<Preparation of Circular Container with Bottom> Six types of two-layer film laminated metal plates prepared by the above method were subjected to seven-step drawing with a lance progressive drawing machine with the two-layer film surface outside, and 10 mmφ. A round container with a bottom having a height of 20 mm was prepared. The obtained bottomed circular container was immersed in a boiling trichloroethylene (boiling point = 87 ° C.) liquid for 15 minutes to wash the oil used in the processing, and then heat-treated at a temperature of 200 ° C.

<Evaluation of Circular Container with Bottom> The obtained circular container with bottom was subjected to an evaluation test for heat resistance and caulking workability by the following method. Table 1 shows the evaluation results. (1) Heat resistance: Maximum temperature reached 1 in 2 minutes using a cylindrical container
After heating to 50 ° C, the maximum temperature reached 27
It was buried by heating to 0 ° C. Visual observation of the appearance of the two-layer composite film after the heat treatment was carried out, and those in which yellowing was conspicuous as compared to those before the heat treatment and those in which the appearance of the two-layer composite film was abnormal were evaluated as "x", Those with no noticeable yellowing and no abnormality in the appearance and the like of the two-layer composite film were each judged as “○”.

(2) Caulking workability: While rotating the bottomed circular container obtained by the above-mentioned drawing at a speed of 100 rpm, a disk-shaped caulking sesame with a thickness of 3 mm (R = 1.
(5 mm semicircle) was pressed and crimped so that the indentation depth became 1.5 mm, and the peeling state at the interface between the two-layer composite film and the aluminum plate was visually observed. A sample where no peeling was observed at the interface was evaluated as “○”, and a sample where peeling was observed at the interface was evaluated as “X”.

(3) Comprehensive evaluation: Taking into account the evaluation results of (1) and (2) above, those that are judged to have no practical problems are indicated by “O”, and those that are judged to have practical problems. To “×”
Respectively.

[0040]

[Table 1]

From Table 1, the following becomes clear. (1) A layer having a compounding ratio and a thickness ratio of 2 in an appropriate range is excellent in both heat resistance and caulking workability and has no practical problem (see Test Examples 1 to 3). (2) Even if the mixing ratio of the layer A is within the appropriate range, the thickness ratio is 2
Is out of the proper range, the heat resistance is poor and there is a practical problem (see Experimental Example 4). (3) Even if the thickness ratio 2 is within the proper range, the one having a compounding ratio of the layer A outside the proper range has poor heat resistance and has a practical problem (see Experimental Examples 5 and 6). In the case of Experimental Example 6, when the oil used in the drawing process was washed with trichloroethylene, the two-layered film was peeled off from the aluminum plate, making it impractical (see Experimental Example 6).

Test Examples 7 to 10 <Preparation of Three-Layer Film> Amorphous polyamide resin of the same type as used in Test Example 1 80% by weight, aliphatic of the same type as used in Test Example 1 A mixture for forming an (A) layer, in which 20% by weight of a polyamide resin was mixed, was used as a raw material. (A) a mixture for forming a layer and (B) an aliphatic polyamide resin for forming a layer,
Using two extruders equipped with a die, melt kneading was performed separately to produce biaxially stretched films having different thicknesses. (A)
A three-layer film having a layer (B) disposed on both sides of the layer,
The total thickness is 20 μm, and the ratio of “thickness ratio 3” is 0.25.
A layer composite film was prepared.

<Preparation of Three-Layer Film-Laminated Metal Sheet> An aluminum sheet of the same type as used in Test Example 1 was subjected to a chemical conversion treatment with a phosphoric acid-chromate treatment solution to give a treated film having a thickness of 20 mmg / m ² . Was formed. After applying an epoxy-based adhesive to the chemical conversion-treated surface to a thickness of 1.4 μm, the three-layer film was stacked and pressed with a heated nip roll to prepare a three-layer film laminated metal plate.

<Preparation of Circular Container with Bottom> The obtained three-layer film laminated metal plate was subjected to 7-step drawing by a lance progressive drawing machine in the same manner as in Test Example 1, and 10 mmφ ×
A round container with a bottom having a height of 20 mm was prepared. Trichloroethylene (boiling point = 87 ° C) boiling the obtained bottomed circular container
After being immersed in the solution for 15 minutes to wash the oil used for processing, it was heated at a temperature of 200 ° C.

<Evaluation of Circular Container with Bottom> The circular container with bottom obtained by washing with a trichloroethylene solution was left for 2 minutes in a drier adjusted to the temperature shown in Table 2, and 3 hours after the heat treatment. The appearance of the layer film, such as discoloration, cracks, and peeling of the film, was visually observed (appearance after heat treatment). When the three-layer composite film did not show any abnormality, it was evaluated as "O", and when it showed abnormality, it was evaluated as "X". Further, an evaluation test for crimping workability was performed in the same manner as in Test Example 1. Table 2 shows the evaluation results.

[0046]

[Table 2]

Table 2 shows the following. (1) Test example 8 in which the heat treatment temperature is lower than the glass transition temperature
Has a practical problem due to film peeling in the evaluation of caulking workability. (2) Test example 9 in which the heat treatment temperature is higher than the glass transition temperature range,
In Test Example 10, there was no practical problem in the appearance after the heat treatment, the caulking workability, and the like. (3) Heat treatment temperature is 300 ° C, polyamide 6 melting point + 50
If the temperature exceeds the upper limit temperature of ° C., there is no problem in the caulking workability, but the yellowing is severe and the commercial value is impaired.

[0048]

The present invention has been described in detail above and has the following particularly advantageous effects, and its industrial utility value is extremely large. 1. In the polyamide-based laminated resin sheet according to the present invention, pinholes, voids, and microcracks hardly occur in the resin film by cold drawing. 2. The polyamide-based laminated resin sheet according to the present invention is not easily yellowed even when exposed to a high temperature, and has an excellent appearance. 3. When manufacturing an outer container for an electrolytic capacitor by the method according to the present invention, even if inconveniences such as pinholes, voids, and microcracks occur in the polyamide resin film by cold drawing, heat treatment is performed in a specific temperature range. By doing so, these disadvantages can be easily repaired. 4. The outer container for an electrolytic capacitor obtained by the production method according to the present invention hardly generates pinholes, voids, and microcracks, and is excellent in appearance, insulating properties, and the like, and of high quality.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a polyamide-based resin-laminated metal plate according to the first invention of the present invention.

FIG. 2 is a cross-sectional view of an example of a polyamide-based resin-laminated metal plate according to a third invention of the present invention.

[Explanation of symbols]

 1: Aluminum thin plate 2: Two-layer film 3: Three-layer film 4: (A) layer composed of a mixture of polyamide resins 5: Layer (B) composed of only an aliphatic polyamide resin

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01G 9/08 B65D 85/38 L 9/00 H01G 9/24 EF term (Reference) 3E033 BA09 BA21 BB08 FA01 GA03 3E096 BA09 CC01 EA02X EA06X EA11X FA07 FA14 4F100 AA22 AB10A AK46B AK48B AK48C AK48D AK53G BA03 BA04 BA07 BA10A BA10B BA10D BA13 CB00 DA01 EJ69 GB16 GB41 JA12B JA20B JA20CJA20D JA20Y JAJYYJG01Y

Claims (5)

[Claims] 1. A metal plate in which a multilayer film made of a polyamide resin is laminated on one side of an aluminum plate, the multilayer film is composed of 50 to 95% by weight of an amorphous polyamide resin and 50 to 5% by weight of an aliphatic polyamide resin. %, And a film having a two-layer structure of a layer (A) composed of a mixture of the above-mentioned two layers and a layer (B) composed only of an aliphatic polyamide resin, and the total thickness of the two-layer film is 5 to 50 μm, and The two-layer film satisfies the relationship of [{(B) layer thickness} / (total thickness of two-layer film)] ≦ 0.3, and is laminated on an aluminum thin plate with (A) layer outside. A laminated metal sheet of a polyamide-based resin characterized by being made. 2. When manufacturing an outer container for an electrolytic capacitor from a metal plate in which a composite film made of a polyamide-based resin is laminated on one surface of an aluminum plate, the multilayer film contains 50 to 95% by weight of an amorphous polyamide resin. (A) layer composed of a mixture of an aliphatic polyamide resin and 50 to 5% by weight, and (B) composed of only an aliphatic polyamide resin.
The two-layer film has a total thickness of 5 to 50 μm, and the two-layer film has a thickness of {{(B) layer thickness} / (two-layer film). )] ≦ 0.3, and is laminated on an aluminum thin plate with the (A) layer outside.
A method for producing an outer container for an electrolytic capacitor, comprising forming a bottomed cylindrical container by drawing with the layer film being on the outside. 3. A metal plate in which a multilayer film made of a polyamide resin is laminated on one side of an aluminum plate, the multilayer film is composed of 50 to 95% by weight of an amorphous polyamide resin and 50 to 5% by weight of an aliphatic polyamide resin. %, And a (B) layer consisting of only an aliphatic polyamide resin are formed into a three-layer film in the order of (B) layer / (A) layer / (B) layer, This three-layer film has a total thickness of 5 to 50 μm, and the three-layer composite film has a thickness of [{(B) layer thickness} / (total thickness of three-layer film)] ≦ 0. 3. A polyamide-based laminated metal sheet, characterized by satisfying the following relationship: 4. When manufacturing an outer container for an electrolytic capacitor from a metal plate in which a multilayer film made of a polyamide resin is laminated on one surface of an aluminum plate, the multilayer film contains 50 to 95% by weight of an amorphous polyamide resin. (A) layer composed of a mixture of 50 to 5% by weight of an aliphatic polyamide resin, and (B) layer composed of only an aliphatic polyamide, in the order of (B) layer / (A) layer / (B) layer. 3 stacked
The three-layer film has a total thickness of 5 to 50 μm, and the three-layer composite film has a thickness of {{(B) layer thickness} / (total of three-layer film). Thickness)] ≦ 0.3. A method for producing an outer container for an electrolytic capacitor, characterized by forming a bottomed cylindrical container by drawing with the multilayer film facing outward. 5. After forming a bottomed cylindrical container by drawing with the multilayer film on the outside, the bottomed cylindrical container is set to have a glass transition temperature of an amorphous polyamide resin as a lower limit temperature,
The heat treatment is performed in a temperature range having an upper limit temperature of the melting point of the aliphatic polyamide resin plus 50 ° C.,
The method for producing an outer container for an electrolytic capacitor according to claim 2 or 4.