JP2602418Y2 - Cartridge filter - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cartridge filter for filtering used for removing solid matter in a liquid, and more particularly to a non-woven fabric-wrapped laminated cartridge filter.

[0002]

2. Description of the Related Art As a cartridge filter for filtering fine particles in a liquid, a cartridge formed by forming a thread, string, paper, non-woven fabric or the like into a porous cylindrical shape is known. But,
Cartridge filters with a porous core wrapped with a filter medium and end caps made of gaskets at both ends have the problem that the end caps are difficult to create and attach, and are costly. A cartridge filter (without end caps) formed by winding a filter medium made of fiber and heating and pressurizing both end faces to form a film becomes a hard film, and cracks are generated by external pressure. There is a problem in that it is apt to occur, a hole is formed, and a leak is likely to occur. Some of these can be dealt with by increasing the density of the filter medium and reducing the pore size.However, increasing the density of the filter medium increases the flow resistance and significantly reduces the service life. occured. Also, there was no way to deal with leaks.

[0003]

Means for Solving the Problems The inventors of the present application have
In order to eliminate these drawbacks, various studies have been made, and as a result, the problems can be solved by fusing the film to both ends of the film cartridge. That is, the invention of this application applies heat to the surface of the porous core.
Both ends of a cartridge filter wound with a plastic fiber filter medium
The film is fused and the film is porous
With the thermoplastic fiber filter protruding from the end of the core,
The present invention relates to a cartridge filter formed by heating and pressurizing a film, wherein elasticity is obtained by a film at both ends of a cartridge filter obtained by the present invention, and leakage can be prevented.

[0004]

More specifically, a cartridge filter having a structure in which a filter medium is wound around a porous core according to the present invention is characterized in that a film is fused to an end face thereof. Is used as a single layer or a multilayer. The film to be attached is an unstretched film, and the film is preferably a composite film composed of two layers of resins having different melting points.

As the single-layer film, for example, a film of polypropylene, polyethylene, polyamide, polyester or the like is suitable, and a mixed resin film is also used. The fusion is performed by heat-pressing the filter medium and the film. It is important that the fusion is performed at a temperature at which the film retains its shape and at the same time exhibits an adhesive property. The unstretched film is preferred because the unstretched film has higher dimensional stability at the time of heat fusion than the stretched film. In addition, the stretched film contains many crystal parts, and it is necessary to heat the film to a high temperature in order to eliminate the crystal parts and obtain a fusion-bondable state.
Deformation is easy to occur, and temperature setting is difficult.

As the multilayer film, polyethylene / polypropylene, polypropylene / modified polypropylene,
Polyethylene terephthalate / copolyester, nylon 6,6 / nylon 6, nylon 6 / copolyamide film and the like are suitable, and a mixed resin film is also used. The fusion is performed by heating and pressing the side of the low melting point component and the filter medium. For example, in the case of a polyethylene / polypropylene film, even though the polyethylene component substantially melts, the polypropylene component retains the shape of the film, so that the processing temperature can be varied.

The fibrous filter media of the present invention include yarns,
Strings, paper, nonwoven fabrics and the like can be used, and nonwoven fabrics are particularly preferred. As the non-woven fabric, a non-woven fabric made of a thermoplastic fiber is preferable because a high bonding strength can be obtained when it is fused with a film. For example, as the nonwoven fabric, a fiber-bonded nonwoven fabric, a melt-blown nonwoven fabric, or the like is suitably used. In particular, meltblown nonwovens are suitable for collecting delicate particles.

[0008] The nonwoven fabric by the melt blow method or the jet spinning method is formed by spraying the fiber stream between a pair of driven rolls, or by accumulating on a conveyor. The melt-blown non-woven fabric accumulated on the conveyor and the melt-blown non-woven fabric accumulated between the rolls are laminated, and since the latter has a function of a spacer together with a filter action, it has a high collecting capacity and a long service life. Suitable as a filter medium because they can be compatible.

As the raw material of the nonwoven fabric, it is preferable to use a thermoplastic resin such as polyolefin, polyamide or polyester in order to enhance the adhesiveness to the film. And
When using a polypropylene resin with a porous core,
It features a cartridge filter made of all polypropylene resin and does not use any binders or adhesives, so it has no problems such as chemical resistance and eluting substances, and also can be autoclaved and at normal temperature It is characteristic that it can withstand up to 90 ° C and is excellent in food hygiene.

FIGS. 1 to 3 show the structure of the cartridge filter of the present invention. In the figure, 1 is a porous core,
2 is a nonwoven fabric (filter medium), 3 is a film, and 4 is a porous net tube. Therefore, FIGS. 2 and 3 show a filter body in which the nonwoven fabric 2 is wound around the porous core 1. FIG. 1 is a partially cutaway perspective view of a cartridge filter, in which a nonwoven fabric 2 is wound around a porous core 1 and a polypropylene resin porous net 4 is disposed outside to protect the filter medium. No. 3 is completely welded to both ends of the cartridge filter by a heat melting method.

[0011] The cartridge filter of the present invention is:
The medium to be filtered is set in the filter housing, and the medium to be filtered is passed through the filter medium from the external porous mesh tube 4 and the internal porous core 1
By filtering through water, it is possible to efficiently remove fine particles in liquids, so that it can be used to filter pure water, solvents, and chemicals in the electronics field, and process water, solvents, and intermediate products in the pharmaceutical and cosmetic drug industries. It is preferably used. Hereinafter, specific examples of the present invention will be described with reference to embodiments.

[0012]

EXAMPLE 1 A fiber diameter of 2 μm and a basis weight of 80 g / m ² were formed on the surface of a porous core.
The melt-blown non-woven fabric is wound together, and the outer diameter is 64m.
m, a cylindrical structure having a winding density of 0.085 g / cm ³ was produced, and both ends were cut parallel to the core cross section so as to protrude 4 mm from the core tip, and an unstretched polypropylene film having a thickness of 0.3 mm was obtained. Apply to both end faces. Then, the plate is heated and pressed at 200 ° C. and 4 kg / cm ² for 6 minutes from both sides using a bowl-shaped mold, cooled, and taken out of the mold.

EXAMPLE 2 A 3 denier, 51 mm fiber length polypropylene / polyethylene composite fiber bonded to the surface of a porous core was used as a carrier material. The carrier material had a fiber diameter of 2 μm and a basis weight of 80 g / m ² . The melt-blown non-woven fabric was wound together to produce a cylindrical structure having an outer diameter of 64 mm and a winding density of 0.09 g / cm ³ , and cut both ends parallel to the core cross section so as to protrude 4 mm from the core tip.
A two-layer film made of low-density polyethylene is applied to both end faces. Then, at 160 ° C, 4 kg /
After thermocompression bonding at 6 cm ² for 6 minutes, it is cooled and taken out of the mold.

Comparative Example 1 In Example 1, after the cylindrical body was manufactured, it was heated and pressed by a mold without applying a film, and then cooled and taken out from the mold.

Comparative Example 2 In Example 2, after the cylindrical body was manufactured, it was heated and pressed by a mold without applying a film, and then cooled and taken out from the mold.

COMPARATIVE EXAMPLE 3 A commercially available cartridge filter in which both end faces of a cartridge wound with a nonwoven fabric are subjected to a heat sealing treatment.

The examples and comparative examples were mounted on a housing to check for leaks. A leak was determined when the trapping efficiency dropped sharply and at the same time the rise in differential pressure stopped. The results of the examples and comparative examples are as shown in Table 1.

[0018]

[Table 1]

[0019]

According to the present invention, it is possible to reliably seal the end face without causing a leak while maintaining an appropriate density of 0.07 to 0.10 g / cm ³ for obtaining a long life of the filter medium. Since the film has elasticity, it is possible to obtain an excellent effect that cracks due to external pressure hardly occur and that the film can be securely sealed with the housing.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of a cartridge filter of the present invention.

FIG. 2 is an explanatory view of a cartridge filter in the process of manufacturing according to the present invention.

FIG. 3 is an explanatory view of a cartridge filter in the process of manufacturing according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Porous core 2 Nonwoven fabric filter material 3 Film 4 Porous mesh tube 5 Outer layer 6 Inner layer

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-70114 (JP, A) Japanese Utility Model 4-99204 (JP, U) Japanese Utility Model 2-137914 (JP, U) Japanese Utility Model Utility 3- 3414 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A thermoplastic fiber filter is wound around a surface of a porous core.
Film is fused to both ends of the turned cartridge filter
The film is hotter than the end of the porous core.
Heat and press the film with the plastic fiber filter medium protruding.
Is not formed by
Cartridge filter.