JPS62258708A - Flat-plate thin membrane laminate type filter - Google Patents

Abstract

PURPOSE:To reduce both the cost of parts and the cost of assembly and to surely perform the sealing by laminating a filter unit which is formed by superposing two sheets of porous thin membranes and involving a support and welding similar peripheral edge parts of the membranes and bonding a gasket by a solvent in the aperture part for taking out fluid incorporated in the membranes. CONSTITUTION:A filter unit 13 is formed by superposing two sheets of porous thin membranes 11 which are made of thermoplastic synthetic resin and have a same shape while involving a support 12 having a circular sheet shape, welding and sealing the similar peripheral edge parts 11e of the membranes 11 wherein the vicinity position of an aperture part 11a for taking out cleaned fluid incorporated in the then membranes 11 is excepted by means of a heat press or the like. The unit 13 is laminated by interposing spacers 14. A laminate 16 is constituted by bonding ring-shaped gaskets 15 provided to the spacers 14 in one body or in a separated body on the outer surface of the vicinity of the aperture parts 11e for taking out cleaned fluid by means of a small amount of solvent.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a flat thin film laminated filter for separating microorganisms or particulates from a raw fluid of liquid or gas using a porous thin film. Especially maximum pore diameter 0.01~10
The present invention relates to a flat thin film laminated filter having a special structure in which a porous thin film having countless micrometer-sized continuous pores is used, and the porous thin film is alternately laminated together with a support, spacers, and the like.

(Prior Art) A flat porous thin film has a high porosity of 60 to 80% and its mechanical strength is extremely weak.

Usually, when used as a filter, a flat plate is placed on a support without being bent, and the filter is sealed with a gasket.

However, in the semiconductor industry or pharmaceutical industry, etc.

When it is necessary to process a large amount of fluid, if a flat membrane is used as it is, the filter housing will become huge. A cartridge filter has been proposed and is being commercialized.

Under the above circumstances, so-called disposable filter elements have recently been developed, but this has a structure in which many small flat membranes are stacked together with supports and spacers to avoid bending of the flat membranes. Twenty types of filters also have drawbacks.

In other words, disposable filters have a complicated structure;
The assembly process is difficult, it requires a sealing structure to seal the membrane, and it is a disposable product.
There is an undeniable problem that the cost is inevitably higher than when using the flat membrane as described above or when using a normal pleated cartridge filter.

Therefore, improved structures such as the first-order type have been proposed as disposable laminated filters.

For example, Japanese Unexamined Patent Publication No. 56-129016 or Japanese Utility Model Application No. 56-129016
It is disclosed in Japanese Patent No. 9-102111.

In the former case, as shown in FIGS. 11A and B and FIGS. 12A to C, the upper and lower surfaces of the support 1 or 6, which has a large number of ribs 1a molded by injection molding, are entirely immersed in a solvent. The porous thin film 2 is bonded and laminated to form a laminated structure, with a protective plate 4 provided with an outflow portion 3 in the upper part and a protective plate 5 provided in the lower part. The porous thin film 2a and the porous thin film 2b, which have different shapes from each other, are adhered to the upper and lower surfaces of the support 1. Further, the support body 6 in FIG. 12 is a combination of an upper plate 6a and a lower plate 6b having mutually different shapes.

As shown in the same publication, the latter method consists of laminating a plurality of support plates at appropriate intervals, covering both sides of each support plate with a porous thin film, and placing a spacer between the laminations on the raw fluid flow path side. At the same time, a bellows-like structure is adopted in which the porous thin films are sealed together at the outer and inner peripheries.

(Problems to be Solved by the Invention) However, the above-mentioned conventional example has the following problems.

That is, in the former case, the porous thin film 2a and the porous thin film 2b having different shapes are required in order to take out the cleaning fluid from between the membranes, or in another form, the support body 6 has different shapes. Since it is a combination of the upper plate 6a and the lower plate 6b, the cost per component or assembly cost is increased. Furthermore, since the entire porous thin film 2 is immersed in the solvent, unnecessary attack may be applied to the porous thin film 2 or the supports 1 and 6, and the remaining solvent may be affected. Since the film is fixed to the ribs 1a on the supports 1 and 6, there are problems such as substantial loss of film area.

The latter coats both sides of each support plate with a porous thin film.

Since it is constructed with a bellows-like structure in which a spacer is provided between the laminated layers on the raw fluid flow path side and the porous thin films are sealed at the outer and inner periphery, the outer or inner periphery is sealed first. However, when it comes to sealing the membranes together, sealing them afterwards requires a physically very unnatural and difficult sealing method, which makes the sealing performance extremely uncertain and the assembly difficult. The method is also complicated, and it must be said that it is a means contrary to cost reduction.

The present invention was developed to solve the above-mentioned conventional problems, and provides a disposable flat thin film laminated filter that satisfies all the requirements such as low parts cost, assembly cost, and sealing reliability. The purpose is to

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a support body inside a flat porous source 11g made of thermoplastic synthetic resin, and this porous thin film is surrounded by a spacer. In a flat plate thin film laminated filter in which a plurality of layers are laminated with the support body interposed therebetween, two porous thin films of the same shape are superimposed with the above-mentioned support included therein, excluding a position near the opening for taking out the clean fluid of the porous thin film. A porous thin film in which a filter unit is formed by sealing the peripheral edges of the porous thin film, a large number of filter units are stacked with spacers interposed therebetween, and a gasket is provided integrally or separately with the spacer. A laminate is formed by adhering the gasket and the porous thin film to the outer surface of the spacer in the vicinity of the opening for taking out clean fluid using a solvent. But,
A solvent that does not dissolve the porous thin film was used. In addition, the support is encapsulated within a flat porous thin film made of thermoplastic synthetic resin,
A laminate is constructed by laminating these porous thin films with spacers interposed, and protective members are provided at both ends of the laminate in the stacking direction, and at the outer peripheral position in the horizontal direction of the laminate.
A configuration was adopted in which a filter cylinder having a pre-filter function of the porous thin film provided on the protection member was provided, and a filter member was provided around the outer periphery of the filter cylinder.

(Function) Therefore, according to the present invention, two porous thin membranes of the same shape are superimposed and the support is enclosed, so that the porous thin membrane is reliably held against the filtration pressure, and the cleaning fluid is A flow path is formed. Moreover, since the filter unit is formed by welding the peripheral edges of the porous thin film to each other except for the vicinity of the clean fluid extraction opening of the porous thin film, it is not only easy to assemble, but also has a permanent sealing function. Furthermore, since a large number of filter units are stacked with spacers interposed between them, the flow path for the raw fluid is effectively ensured, and the back pressure from the clean fluid side can be reliably resisted.

Furthermore, a gasket provided integrally with the spacer or separately is adhered with a solvent to the outer surface of the porous thin film in the vicinity of the opening for taking out the clean fluid, thereby constructing a laminate.

As the assembly process is simplified and the sealing function is reliable, mixing of clean fluid (filtrate, clean gas) and raw fluid (undiluted solution, contaminated gas) can be avoided, and microorganisms in liquid or gaseous fluids can be avoided. and fine particles can be separated and flowed out from the outlet.

(Example) Figures 1 to 4 show an example of a flat plate thin film laminated filter according to the present invention. 3 is a cross-sectional view showing another example of the total filtration type, and FIG. 4 is a cross-sectional view showing another example of the cross-flow type.

In the drawings, reference numeral 11 indicates a flat porous thin film having numerous continuous pores with a maximum pore diameter of about 0.01 to 10 μm, and the porous thin film 11 in this example has a circular shape, and further includes:
In Figure 1 (full filtration type), clean fluid (filtrate) is located in the center.
Open the extraction opening 11a, and open it as shown in Fig. 2 (cross flow type)
There are two clean fluid extraction openings 11 on the left and right planes.
b, 11c and a central opening Lid. Two porous thin films 11.11 of the same shape are formed into a circular sheet-like support 1.
2 and stacked on top of each other, and the peripheral edges 11e and llf of the porous thin film 11 except for the positions near the clean fluid extraction openings 11a to 11c of the porous thin film 11 are welded and sealed by means such as hot press. Stop, filter unit Y3
form. A large number of filter units 13 are stacked with a spacer 14 having an opening 14a and a rib interposed therebetween, and a ring-shaped gasket 15 is provided on the spacer 14 either integrally or separately. A laminate 16 is formed by adhering the porous thin film 11 to the outer surface of the porous thin film 11 in the vicinity of the opening for taking out the clean fluid with a small amount of solvent.

The support body 12 or spacer 14 described above may be a porous material such as a mesh, nonwoven fabric, or woven fabric formed by a continuous processing method that is more productive than injection molding, or a uniform uneven surface formed by extrusion molding or the like. It can be easily obtained by selecting a sheet plate or the like having a 100% diameter and punching out a relatively inexpensive material.

In addition, the spacer 14 is provided with a gasket 1 integrally or separately.
In this example, a separate gasket 15 that fits into the opening of the spacer 14 is provided. The above-mentioned porous thin film 11 is bonded with a solvent to the outer surface near the opening for taking out the clean fluid to ensure sealing. Although materials that are compatible are selected and solvents that dissolve each other are used, this principle is not applied to the solvent bonding of the porous thin film 11 in this embodiment.

That is, the surface of the gasket 15 is dissolved using a solvent that does not dissolve the porous thin film 11 but dissolves the target synthetic resin gasket 15, and then the porous thin film 11 is dissolved.
When pressed, the melted resin on the surface of the gasket 15 enters the pores of the porous thin film 11 and is securely bonded. Furthermore, if a solvent with a boiling point as low as possible is used, there will be virtually no toxicity problems due to residual solvent or deterioration of parts over time, and substantially the same effect as thermal welding can be obtained. To enumerate specific combinations, for example, in the case of a porous thin film of cellulose acetate, the gasket is preferably polysulfone or polycarbonate, and the solvent is preferably trichlorethylene.

If a porous thin film with relatively high solvent resistance is used, such as polyamide, polypropylene, polyethylene, or fluororesin,
A very wide range of solvents and gasket materials are available.

Further, protection members 17 and 18 having ribs on the inner surface are provided at both ends of the stacked body 16 in the stacking direction, and a raw fluid inlet 19 and a clean fluid outlet 20 are provided in one or both of these protection members.

FIG. 1 shows an example in which the protective member 17 is provided with a clean fluid outlet 20, and FIG. 2 shows an example in which the protective member 17 is provided with an original fluid inlet 19 and clean fluid outlets 2Q and 20.

Furthermore, as shown in FIG. 3, a support cylinder 21 having a communication hole 21a is provided in the clean fluid extraction opening 16a formed in the laminate 16, and this support cylinder 21 is provided at both ends of the laminate 16 in the stacking direction. The laminate 1 is fixed to the protective members 17 and 18.
6 reinforcing functions.

The support cylinder 22 shown in FIG. 4 is constituted by a combination of the protruding cylinder part 23a of the spacer 23 and the protruding cylinder part 24a of the protection member 24, and a communication hole 22a is formed in the support cylinder 22.

The laminate 16 and protective members provided at both ends of the laminate 16 in the stacking direction are housed in two lower housings 25 and 26 to form a filter 27. Specifically, in the ninth figure, the outflow part 25a of the upper housing 25 and the outflow port 20 of the protection member 17 are assembled via an O-ring 30, and the lower housing 26 and the upper housing having an inflow part 26a and a protrusion 26b are assembled. Assemble the filter 27 using 25.

Next, the operation of the above embodiment will be explained.

Since the two porous thin membranes 11.11 of the same shape are superimposed and the support body 12 is enclosed, the porous thin membrane 11 is reliably held against the filtration pressure, and a filtration channel is formed. , the opening 11a of this porous thin film 11 for taking out the clean fluid.
Peripheral area of porous thin film 11.11 except for the vicinity of
Since the filter unit 13 was formed by welding ie and llf.

Not only is it easy to assemble, but it also exhibits a permanent sealing function.
4, the flow path for the raw fluid is effectively ensured and counter pressure from the clean fluid side can be reliably resisted.

Furthermore, the gasket 15 provided integrally with the spacer 14 or separately is adhered to the outer surface of the porous thin film 11 in the vicinity of the opening for taking out the clean fluid to form the laminate 16, thereby simplifying one assembly process. At the same time, mixing of the clean fluid and the raw fluid can be avoided, and microorganisms and particulates in the liquid or gas raw fluid can be reliably separated and allowed to flow out from the outlet.

Next, FIGS. 5 to 8 are sectional views showing aspects of other embodiments of the present invention.

Identical parts between this embodiment and the above-described embodiments are denoted by the same reference numerals, and explanations thereof will be omitted.

In the drawing, a support body 12 is included in a flat porous thin film 11 made of thermoplastic synthetic resin, and this porous thin film 11 is laminated with spacers 14 interposed to form a laminate 16. Protective members 17.1 are placed at both ends in the stacking direction of 16.
8 is provided, and at the outer peripheral position in the horizontal direction of the laminate 16,
Pre-filter of porous thin film 11 provided on the protection member
A filter cylinder 28 having a function is provided, and the filter cylinder 28 forms a large number of openings 28a. By providing the filter member 29 on the outer periphery of the filter cylinder 28, the pre-filter function of the porous thin film 11 is increased.

When the above-mentioned laminate 16 and the retainer members 17 and 18 provided at both ends of the laminate 16 in the stacking direction are housed in the upper and lower housings, a product similar to the filter shown in FIG. 9 can be manufactured.

(Effects of the Invention) As is clear from the above, the present invention has the following excellent effects.

In other words, it has become possible to provide a disposable type flat thin film laminated filter that satisfies all requirements such as low single-part cost, low assembly cost, and reliable sealing.

Specifically, as a sealing means to avoid mixing of the clean fluid and raw fluid, a safe and reliable seal is achieved by thermally welding the two together and bonding the gasket and the porous thin film using a small amount of solvent. Stopping properties can be easily achieved.

In addition, compared to conventional sealing methods, there is no need to immerse the entire porous thin film in a solvent, and only the minimum amount of solvent necessary is used, which greatly reduces problems caused by residual solvent, and eliminates the need to immerse the entire porous thin film in a solvent. The attack of the support and the porous thin film by the solvent is minimized, and in particular, the problems of the hydrophilic agent and various resin additives flowing out of the porous thin film can be solved at once.

Furthermore, since the supports and spacers are continuously molded without injection molding, it is possible to make the walls thinner, which reduces the overall thickness of the laminate, making it more compact as a whole. effective.

[Brief explanation of drawings]

1 to 4 show an embodiment of the flat plate thin film laminated filter according to the present invention. FIG. 1 is a sectional view of a full filtration type filter, FIG. FIG. 3 is a sectional view showing another example of the total filtration type, FIG. 4 is a sectional view showing another example of the gross flow type, and FIGS. 5 to 8 show each aspect of other embodiments of the present invention. 9 is a sectional view showing an example of a filter in which a flat plate thin film laminated filter according to the present invention is housed in a housing, FIG. 10 is an exploded perspective view of the filter unit, and FIG. 10B is the same unit. and FIG. 10C are separated perspective views of the filter according to the present invention, and FIGS. 11A and 11B and FIGS. 12A to 12C show a part or the whole of the conventional example, respectively. FIG. 11... Porous thin film 11a, llb, 11c... Removal opening 11o,
llf...Peripheral portion 12...Support body 13...Filter unit 14.
23...Spacer 15...Gasket 16...Laminated body 17.18.
24... Protective member 19... Original fluid inlet 20... Clean fluid outlet
21, 22...Support cylinder 25...Upper housing 26...Lower housing 27...Filter Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 7 Fig. 8 Fig. 28 M 75 7j It 71
T H11377e Fig. 9 Fig. 11 (A) b Fig. 11 <8)

Claims (12)

[Claims] (1) A flat thin film laminated filter in which a support is encapsulated in a flat porous thin film made of thermoplastic synthetic resin, and a plurality of these porous thin films are laminated with spacers interposed therebetween, in which the support is encapsulated. A filter unit is formed by overlapping two porous thin films of the same shape and sealing the peripheral edges of the porous thin films except for the vicinity of the clean fluid extraction opening of the porous thin film. The filter units are laminated with a spacer interposed therebetween, and a gasket provided integrally with or separately from the spacer is adhered with a solvent to the outer surface of the porous thin film in the vicinity of the clean fluid extraction opening to form a laminated body. A flat plate thin film laminated filter characterized by the following structure. (2) The total filtration type flat plate thin film laminated filter according to claim 1, wherein protective members are provided at both ends of the laminated body in the laminating direction, and a clean fluid outlet is provided on one of the protective members. (3) A cross-flow type flat thin film lamination according to claim 1, wherein protective members are provided at both ends of the laminated body in the lamination direction, and a raw fluid inlet and a clean fluid outlet are provided on one side of the protective member. type filter. (4) The solvent for bonding the gasket and the porous thin film provided integrally or separately to the spacer is a solvent that dissolves the gasket but does not dissolve the porous thin film. 3. The flat thin film laminated filter according to item 3. (5) The flat thin film laminated filter according to claims 1 to 4, wherein the porous thin film has a maximum pore diameter of 0.01 to 10 μm. (6) A support cylinder having a communication hole is provided in the raw fluid extraction opening formed in the laminate, and the support cylinder is fixed to a protective member provided at both ends of the laminate in the stacking direction. 5. The total filtration type or cross-flow type flat plate thin film laminated filter according to item 5. (7) The support tube according to claim 6 is a full filtration type or a cross tube, which is constructed by a combination of the protruding tube portion of the spacer and the protruding tube portion of the protective member, and has a communication hole formed in the support tube. Flow type flat thin film laminated filter. (8) The full filtration type or cross according to claims 1 to 7, wherein the laminate and protective members provided at both ends of the laminate in the stacking direction are housed in upper and lower housings to constitute a filter. Flow type flat thin film laminated filter. (9) A support is encapsulated in a flat porous thin film made of thermoplastic synthetic resin, and the porous thin films are laminated with a spacer interposed between them to form a laminate, with both ends extending in the stacking direction of the laminate. 1. A flat plate thin film laminated filter characterized in that a protective member is provided on the laminate, and a filtration cylinder having a pre-filter function of the porous thin film provided on the protective member is provided on the outer periphery of the laminate in the horizontal direction. (10) The flat plate thin film laminated filter according to claim 9, wherein the filter cylinder has a large number of openings. (11) A flat thin film laminated filter according to claim 9 or 10, wherein a filter member is provided on the outer periphery of the filter cylinder. (12) A flat thin film laminated filter according to claims 9 to 11, wherein the laminate and protective members provided at both ends of the laminate in the stacking direction are housed in upper and lower housings to constitute a filter. .