JP2001276579A - Method for manufacturing chamber frame for dialytic cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chamber frame for a dialytic cell easy to manufacture, stable in quality, low in cost and excellent in heat resistance and sealability. SOLUTION: Frame-shaped sheets 1 made of a thermoplastic elastomer and a resin spacer net 2 are integrated by superposing the outer periphery of the net and the inner peripheries of the sheets one upon another to heat and press them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a dialysis tank room frame structure which is easy to manufacture, has stable quality, is inexpensive, and has excellent heat resistance and sealability.

[0002]

2. Description of the Related Art An electrodialysis cell using an ion exchange membrane, which is widely known at present, is usually of a tightening type, and a cation exchange membrane and an anion exchange membrane are alternately laminated with a chamber frame interposed therebetween to form an electrode. The concentrating chamber and the desalting chamber are alternately formed inside by arranging them in between and tightening both ends with a tightening frame. Here, the chamber frame has a function of maintaining the interval between the cation exchange membrane and the anion exchange membrane in the concentration chamber or the desalination chamber inside a frame-like sheet forming the side wall of the concentration chamber or the desalination chamber. And a liquid-permeable spacer.

Conventionally, the chamber frame used in the dialysis tank has been manufactured as follows. That is, a thermoplastic resin sheet having an opening forming a frame portion of a chamber frame and a net (for example, made of polypropylene) serving as a spacer provided in a flow path of the chamber frame are punched into predetermined shapes, and an ultrasonic spot is formed. Using a welder, place the net inside the frame-shaped sheet and temporarily fix it. Subsequently, the semi-finished product temporarily fixed was welded and integrated with the outer peripheral end of the net to the peripheral end of the opening of the frame-shaped sheet using a large ultrasonic welder to obtain a finished product.

According to this method, the ion exchange membrane is damaged and the liquid leaks when used as a chamber frame due to a large amount of bending and wrinkling of the net and a large uneven thickness of a welded portion between the frame-shaped sheet and the net. In some cases, an increase in the amount resulted in deterioration of the dialysis performance.

Further, according to this method, when ribs are formed in the chamber frame portion to further improve the sealing performance, the shape of the ribs is determined by the surface shape of the material sheet. Therefore, due to the sheet manufacturing method, only a continuous pattern such as a cross rib shape or an emboss shape can be obtained, and an appropriate rib shape for improving the sealing performance cannot be easily formed.

[0006]

SUMMARY OF THE INVENTION From such a viewpoint,
There has been a demand for a method for manufacturing a dialysis tank chamber frame which is easy to manufacture, has stable quality, is inexpensive, and has excellent heat resistance and sealability. An object of the present invention is to provide a method for manufacturing a dialysis tank chamber frame that has solved the above-mentioned problems.

[0007]

According to the present invention, a frame-like sheet made of a thermoplastic elastomer and having an opening is overlapped with a resin spacer net around the outer periphery of the spacer net and the inner periphery of the frame-like sheet. The present invention provides a method for producing a dialysis tank chamber frame, wherein the method is performed by combining and hot pressing.

[0008] The present invention proposes a method of manufacturing a chamber frame for a dialysis tank as described above.
It is particularly suitable as a method for manufacturing a chamber frame used in an electrodialysis tank using an ion exchange membrane to obtain ultrapure water.
It is also effective as a method for manufacturing a chamber frame used in various types of dialysis tanks for desalination for removing salt from a liquid containing salt.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the material of a frame-like sheet forming a frame portion having an opening serving as a liquid flow path is made of a thermoplastic elastomer which is integrated with a net by heating. Anything can be used. In this case, the dialysis tank is operated at a high temperature (50 ° C.
Taking into account the heat resistance during the operation under the above conditions, the softening temperature is 120 ° C. or higher, and the material hardness (JIS K6301, A
Shape) Hardness 60 or more, Compression set (JIS K63)
(01, 70 ° C., 22 hours) 60 or less is desirable. Specifically, a thermoplastic resin elastomer such as polyolefin, polyurethane, or polyester is preferably used.

Any material can be used for the spacer net as a spacer disposed in the flow path which is the opening of the chamber frame, as long as it can be integrated with the frame-like sheet by heating. Considering heat resistance and durability, polypropylene is the best, and resin such as polyethylene is desirable.

[0011] These sheets and nets are punched by a predetermined punching die, formed into a predetermined shape, then overlapped on a hot press, and integrated by hot press working. At this time, the frame-like sheet having the opening and the spacer net are generally overlapped with each other so that the outer periphery of the spacer net and the inner periphery of the frame-like sheet overlap.

More specifically, the size of the spacer net is larger than the opening serving as the liquid flow path formed in the frame-shaped sheet, and the end of the net is 5 to 5 inward from the outer periphery of the chamber frame-shaped sheet. 20 mm, preferably 10 mm
It is desirable to set so as to be superimposed so as to be positioned on the inner side. By doing so,
Even when the adhesion between the spacer net and the frame-shaped sheet is poor, it is possible to effectively prevent liquid leakage to the outside.

Although the temperature of the heating press slightly varies depending on the material used, a temperature at which the spacer net disposed in the liquid flow path of the chamber frame is slightly melted and thermally deformed, specifically, 15 ° C.
0 ° C. or higher, preferably about 155 to 165 ° C., is desirable.

The method of the present invention can be obtained by superposing the spacer net and the frame-like sheet on each other and heating and pressing them.
It is also suitable for making better room frames easily. That is, in order to enhance the sealing performance, if necessary, a linear rib is provided on the frame portion of the frame-like sheet constituting the chamber frame, and an O-ring-like rib is provided around the liquid supply duct portion formed on the frame portion. It is effective to provide the ribs in advance, but in the present invention, it is easy to form these ribs simultaneously with the integrated heating of the sheet and the net.

In the present invention, as a press die of the heating press machine, a die which can arbitrarily form a linear rib for enhancing the sealing performance and an O-ring-like rib around the liquid supply duct portion can be easily manufactured. A liquid seal shape suitable for the use of the chamber frame can be easily formed.

According to the present invention, at least one spacer net and at least one frame-like sheet are alternately heated, and usually a plurality of the spacer nets are alternately stacked and heated and pressed. The spacer net and the frame-shaped sheet can be simultaneously laminated and integrated. For example, the net and the sheet together are 5
More than one sheet can be heated and pressed simultaneously.

FIG. 1 shows a typical stacking method during hot pressing according to the present invention. First, a frame-like sheet 1 for forming a frame portion is placed on a heating press, a spacer net 2 is placed thereon, and the same frame-like sheet 1 is placed thereon. Indicates that they are stacked so as to be pinched around the inside.

FIG. 2 schematically shows an example of the shape of the chamber frame manufactured by the method of the present invention. 2, reference numeral 3 denotes a chamber frame portion of the frame-shaped sheet, 4 denotes a liquid flow path formed in the chamber frame, and the chamber frame portion 3 includes a duct peripheral rib 6,
An outer peripheral rib 7 is formed. These ribs 6 and 7
Is formed simultaneously with the integration of the frame-shaped sheet and the spacer net by a press die during hot press molding. Reference numeral 5 denotes a liquid supply duct hole, which is formed by finish punching after hot pressing.

[0019]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1 (Example) As a frame-shaped sheet, a sheet (thickness: 700 μm) made of a polyolefin-based thermoplastic resin elastomer (thermolan 3801 manufactured by Mitsubishi Chemical Corporation) was punched out by a punching die.
180mm x 550mm outer diameter, inner diameter (opening diameter) 140
One having a size of mm × 450 mm was used.

As a spacer net to be a spacer, a polypropylene net (TTX275P manufactured by Nippon Netron Co., Ltd .: yarn diameter 300 μm, pitch 3 mm, intersection thickness 0.6 mm) is punched by a punching die, and the outer shape 1
One having a size of 60 mm × 530 mm was used.

These are superimposed on a heating press in the order of one sheet, three spacer nets, and one sheet so that the outer periphery of the net overlaps the inner periphery of the sheet with the same width, and is integrally formed by hot pressing. It has become. At this time, the heating press temperature was set at 160 ° C., the press pressure was 5 MPa,
The heating time was 3 minutes. Then, after cooling this with a cooling press, a liquid supply duct hole (diameter 25 mm) was formed by finish punching, and a room frame of a final product was obtained very easily.

[Example 2 (Example)] Heating was performed in the same manner as in Example 1 except that a frame-shaped sheet having an outer shape of 180 mm x 550 mm and an inner diameter (opening diameter) of 138 mm x 438 mm was used. Sheet 1 on press
Sheets, three spacer nets, and one sheet were superposed in this order so that the outer periphery of the net overlapped the inner periphery of the sheet with the same width, and were integrated by hot pressing. At this time, the heating press mold had a width of 3 mm and a depth of 2 mm so that the duct peripheral rib and the outer peripheral rib could be formed in the chamber frame portion.
One having a groove of mm was used.

At this time, the heating press temperature is set at a preset temperature of 16.
At 0 ° C., the pressing pressure was 5 MPa, and the heating time was 3 minutes.
Then, after cooling this with a cooling press, a liquid supply duct hole (diameter 25 mm) was formed by finish punching, and a room frame of a final product was obtained very easily.

[Evaluation Results] The chamber frames obtained in Examples 1 and 2 were used in a device for evaluating the sealing performance of the chamber frames, and the sealing performance was evaluated. In the evaluation, a plate-shaped chamber frame made of polypropylene, an ion-exchange membrane, the obtained chamber frame,
The five chamber frames obtained were assembled in the order of the ion exchange membrane and the plate-shaped chamber frame made of polypropylene, and the tightening pressure was 1MP.
After tightening at a, insert compressed air inside the chamber frame,
The pressure was set to 0.3 MPa, and the amount of air leakage to the outside was measured. As a result, in each of Example 1 and Example 2, the amount of air leakage was 10 cm ³ / h or less, and almost no leakage was observed.

[0026]

According to the present invention, it is possible to obtain a dialysis tank chamber frame which is easy to manufacture, has stable quality, is inexpensive, and has excellent heat resistance and sealability. Furthermore, by selecting the shape of the heating press mold, a dialysis tank chamber frame having ribs having better sealing performance can be obtained.

[0027]

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing how a frame-shaped sheet of the present invention and a spacer net are overlapped.

FIG. 2 is an explanatory view schematically showing an example of a chamber frame manufactured according to the present invention.

[Explanation of symbols]

 1: Frame-like sheet 2: Spacer net 3: Chamber frame part 4: Chamber frame channel 5: Liquid supply duct hole 6: Duct peripheral rib 7: Peripheral rib

Claims (2)

[Claims] 1. A frame-like sheet made of a thermoplastic elastomer and having an opening, and a resin spacer net are superposed on the outer periphery of the spacer net and the inner periphery of the frame-like sheet, and are integrally formed by hot pressing. A method for producing a dialysis tank chamber frame, comprising: 2. The method according to claim 1, wherein ribs are formed on the surface of the frame-shaped sheet during hot pressing.