JP2662702B2 - Manufacturing method of foam metal - Google Patents

Description

The present invention relates to a foamed metal having continuous air holes used for a battery electrode, various filters, a catalyst carrier, and the like, that is, a metal body having a three-dimensional network structure. The present invention relates to an improvement in a method of metal plating for manufacturing.

"Prior art" To produce the above foamed metal, first, a polyurethane foam, a nonwoven fabric, a felt, etc. having continuous pores are used as a base material, and the skeleton surface is formed on the base material by a method such as electroless plating, vacuum deposition, sputtering, and carbon coating. The metal is electroplated to the required thickness on the surface of the skeleton. The obtained base material is roasted to burn off the resin component, and then the oxidized metal is reduced to form a foamed metal.

In order to perform this electroplating, a batch-type method in which a rectangular plate-like base material with conductivity is fixed to a metal plating frame and this is used as a cathode and a band-like base material as a more efficient method are used. For example, JP-B-57-39317, JP-A-61-2
As shown in 07592, a method of continuously electroplating with an apparatus as shown in FIG. 4 is used. That is, in FIG. 4, the long polyurethane foam 1 is sent out in the direction of the arrow in the drawing, and is first immersed in the plating solution 7 in the primary plating tank 5 along the rotating cathode body 4 while the primary polyurethane is applied by the current between the anode 6 and the primary plating bath 7. Then, plating is performed to a suitable thickness by passing current between the rotating cathodes 8, 8 ',... In the next plating baths 10, 10',.

In the case of foamed metal used in the above-mentioned applications, it is necessary to provide an internal communication space, that is, a communication vent hole. For example, in the case of foamed plastic such as polyurethane foam, a cell (closed space) membrane formed in a foaming step is formed, for example, in Japanese Patent Publication No. 57-21507.
As shown in the item, it is manufactured by immersing the film in a solution of an alkali hydroxide substance or removing the film by igniting oxygen and hydrogen in a pressure case. The device for removing the cell film can process only up to a length of about 3 m. Therefore, in the case of the base material according to this method, the connection operation must be repeated in the case of the batch plating method or in the case of continuous electroplating, which is inefficient.

On the other hand, in the so-called peeling method developed by Bridgestone Corporation, a polyurethane foam having a long sheet-like coil having a length of about 60 m can be manufactured from a polyurethane foam having continuous ventilation holes, and is commercially available. If this long sheet-shaped coiled polyurethane foam is used, continuous electroplating can be effectively performed. The long polyurethane foam produced by this peeling method cannot use the outer peripheral part and the central part, so the yield is reduced by more than 30% compared with the case of using a batch type shortened sheet, and it is expensive, but the continuous plating method is used. In this case, there is no connection work and no stoppage of the device accompanying the connection work as compared with a short object.

"Problems to be Solved by the Invention" The polyurethane foam produced by the peeling method is provided as a continuous coiled sheet having a thickness of 2 mm and usually about 60 m. However, when electroplating with a large amount of continuous plating equipment, the length is still insufficient, and about
There is a problem that the power needs to be supplied completely continuously without stopping the apparatus every 60 m.

Conventionally, in order to solve this problem, as shown in FIG. 3, the ends of the polyurethane foam coil sheets 1 and 1 'are overlapped with each other and conductive metal wires such as copper wires 2 are used for mutual connection. Was sewn and connected. However, as can be seen from the drawing, in this method, the thickness of the overlapping seam is at least twice the thickness of the single polyurethane foam, for example, 4 mm or more when the single thickness is 2 mm, and the copper wire projects further outward. When passing through a continuous plating apparatus, there is a problem that the sheet often breaks and breaks when passing through a narrow portion of the apparatus.

"Means for Solving the Problems" In order to solve the above problems, the present invention is characterized in that a stapler (used for binding paper such as documents) is used for connection between coil sheets of polyurethane foam. Things. The seams may then overlap or abut the edges of the sheet.

The present invention will be described in detail with reference to the drawings. As shown in FIG.
The ends of 1 ′ are overlapped and bound with the stapler 3. This connection can be firmly connected unlike the sewing of copper wires, and the stapler needle is made of metal and has conductivity, so that both coil sheets are completely electrically connected. Further, in the case of the stapler needle, since the polyurethane foam is compressed and connected from both sides, the swelling is small, so that the passage through the continuous electroplating apparatus is not hindered.

FIG. 3 is a drawing showing another specific example, and shows a coil sheet.
This shows a state where the ends of 1, 1 'are abutted and connected by a stapler needle 2. Also in this case, both coil sheets are mechanically firmly and electrically connected, and the swelling is small, so that a narrow portion of the plating apparatus can be run well.

[Effects of the Invention] As described above, according to the present invention, in order to manufacture a foamed metal, when a long sheet such as a polyurethane foam is continuously electroplated, the ends of the sheet are connected with a stapler needle. With a simple operation, it is mechanically stronger and electrically connected compared to the connection using a conductive wire such as a conventional copper wire, and it easily passes through the narrow passage of the plating device and is caught. This has the effect of preventing breakage due to cracks.

In particular, a butt joint is effective in preventing breakage.

[Brief description of the drawings]

1 and 2 are cross-sectional views each showing a seam of a coil sheet according to the method of the present invention, FIG. 3 is a cross-sectional view showing a seam formed by a conventional method, and FIG. 4 is a front view showing a continuous plating apparatus. 1,1 ',: Strip-shaped foam plastic base material 2: Stapler, 3: Copper wire 4,8,8' ,: Rotating cathode 5,10,10 ': Plating bath 6,9: Cathode, 7: Plating solution

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-50-36320 (JP, A) JP-A-53-106346 (JP, A) JP-A-55-69285 (JP, A) 50737 (JP, B2)

Claims (2)

(57) [Claims] 1. A foamed plastic resin sheet having a three-dimensional network structure having an internal continuous space is used as a base material, a) a step of subjecting the sheet to a conductive treatment, b) a step of electroplating metal, and c) a base material Removing the resin by roasting to form a foamed metal; and d) then reducing the oxidized metal portion of the sheet by a reduction treatment. The end of one sheet of paper, felt, etc. wound into a band-shaped coil is stapled with the end of another sheet (used to bind paper such as documents)
A method for producing a foamed metal, wherein a sheet wound around the coil is sent to a step of continuously electroplating by connecting with a needle. 2. The method for producing a foam metal according to claim 1, wherein said connecting means connects the end faces of the sheets with a stapling needle.