JPH1071313A - Fibrous filter and manufacture of fibrous filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fibrous filter with light weight and low pressure loss at a low cost by forming an adhesive resin layer with a low melting point on the surface of hollow filaments with hollow structure and thermally melting and fixing the adhesive resin layer. SOLUTION: An adhesive resin layer 8 with a melting point as low as 110-150 deg.C melting point is formed and fixed on the surface of hollow filaments 6 and filled filaments 5, which are filaments of a polyester resin with about 10-70μm thickness, to give a thermally melted fiber 9. A fiber assembled body mixed by about 30% of the thermally melted fiber 9 with hollow filaments 6 is arranged on a forming stand and a wind as hot as 120 160 deg.C is blown the fiber assembled body to melt the adhesive resin layer 8 on the surface of the thermally melted and fixed fiber 9 and give a fiber sheet-like fibrous filter in which filaments are thermally melted one another at crossing points. Consequently, the material cost is suppressed to low and a filter with light weight and low pressure loss can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fibrous filter used for purifying air mainly in the field of general air conditioning and a method for producing the fibrous filter.

[0002]

2. Description of the Related Art As described in Japanese Patent Application Laid-Open No. 58-11339, for example, such a conventional fibrous filter of this type is mixed with a solid monofilament having a solid structure to form a vent having a random composition in the fiber direction. It is configured as a fiber sheet, which is a fiber aggregate having properties. The solid single fibers of the fiber sheet are connected to each other and fixed by spraying or dipping an adhesive. Since the fibrous filter having such a configuration is lightweight and can be manufactured relatively inexpensively, it is widely used as a filter for collecting oil dust and a filter for a heat exchange ventilator in front of a ventilation fan.

[0003] Although not a fibrous filter, there is also a gas filtration apparatus using fibers as disclosed in Japanese Utility Model Laid-Open No. 55-141532, for example. In this method, fine particles of the order of submicrons are filtered using a hollow fiber bundle to obtain a clean gas. The hollow fiber bundle, which is the main filter, has minute holes, and the hollow portion of the hollow fiber bundle functions as a passage for filtered clean air. And the pressure loss is too large to be very applicable.

[0004]

In the above-mentioned conventional fibrous filter used for general air-conditioning, since the whole is composed of solid single fibers, the material cost is high and the cost is high. There is a point. For example, a filter for a ventilation fan is provided as a disposable part, which is usually replaced in a couple of months, and an old one is discarded because the air volume is reduced due to the clogging of oil dust. . Conventional fibrous filters are expensive as such disposable parts, and have a problem from the viewpoint of resource saving.

Further, since the solid single fibers are connected to each other by spraying or dipping the adhesive, a large amount of adhesive is required, and a thin film is easily formed between the solid single fibers at the manufacturing stage due to the surface tension of the adhesive. . When such an adhesive thin film is formed, air permeability is impaired, pressure loss is increased, and the replacement period of the fibrous filter is shortened.

[0006] The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to obtain a lightweight fibrous filter capable of suppressing material costs. The purpose is to obtain a low-cost fibrous filter whose function can be easily obtained, to obtain a lightweight and low-cost fibrous filter, and to improve the trapping ability of the fibrous filter. It is an object of the present invention to reduce the pressure loss of a filter, and to obtain a method for producing a fibrous filter having a low cost and a low pressure loss.

[0007]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 is based on a heat-sealing hollow fiber obtained by forming a low melting point adhesive resin layer on the surface of a hollow single fiber having a hollow structure. A means for thermally fusing the fibers to each other with an adhesive resin layer is used.

[0008] In order to achieve the above object, the invention of claim 2 employs means for connecting fibers of an air-permeable fiber aggregate made of hollow single fibers having a hollow structure with an adhesive.

[0009] In order to achieve the above object, the invention of claim 3 provides a hollow single fiber having a hollow structure and a solid single fiber having a solid structure,
A low-melting adhesive resin layer is formed on the surface of at least one of these hollow monofilaments or solid monofilaments to form a heat-fused fiber, and a breathable fiber assembly obtained by mixing hollow monofilaments and solid monofilaments Means for thermally fusing the fibers to each other with heat-fusible fibers is employed.

In order to achieve the above object, a fourth aspect of the present invention provides an air-permeable fiber assembly in which a hollow monofilament having a hollow structure and a solid monofilament having a solid structure are mixed with each other by an adhesive. Adopt means.

[0011] In order to achieve the above object, an invention according to claim 5 includes a hollow single fiber having a hollow structure and a solid single fiber having a solid structure,
Means is employed in which a fiber aggregate in which a heat-fused fiber mixed with a heat-fusible fiber having a low-melting adhesive resin layer formed on the surface is heat-fused with the heat-fused fiber.

[0012] In order to achieve the above object, the invention of claim 6 provides a means for making the hollow monofilament and the solid monofilament substantially the same in the means according to any one of claims 3 to 5. adopt.

In order to achieve the above object, a seventh aspect of the present invention is a means for providing a difference between the thickness of the hollow single fiber and the solid single fiber in the means according to any one of the third to sixth aspects. Is adopted.

In order to achieve the above object, the invention according to claim 8 is characterized in that the area of the solid portion of the hollow monofilament and the solid monofilament in the means according to any one of claims 3 to 6 is substantially reduced. In the same manner, means for making the outer diameter of the hollow single fiber larger than the outer diameter of the solid single fiber is employed.

According to a ninth aspect of the present invention, there is provided the solid monofilament according to any one of the third to eighth aspects, wherein the solid single fiber has a cross-sectional shape such as a cross or a star. A means composed of non-circular fibers having a wide non-circular shape is employed.

In order to achieve the above object, a tenth aspect of the present invention is to form a low melting point adhesive resin layer on at least one surface of a hollow single fiber having a hollow structure and a solid single fiber having a solid structure. After mixing the fiber and the solid single fiber to obtain a permeable fiber aggregate, a means for heat-treating the fiber aggregate and thermally fusing the fibers to each other with an adhesive resin layer is employed.

[0017]

Embodiments of the present invention will now be described with reference to the drawings. Embodiment 1 FIG. The fibrous filter 1 according to the first embodiment shown in FIG. 1 is used for cleaning air in a general air-conditioning field, and the one shown in FIG. It is a disposable filter that collects oil dust from suction air. FIG. 3 shows a filter that is mounted on the inlet side of the heat exchanger 4 of the air-conditioning ventilator 3 and that is used repeatedly to collect dust in the air. Each of these fibrous filters 1 has a fiber composition, and is composed of a solid monofilament 5 having a solid structure as shown in a sectional structure in FIG. 4 and a hollow single fiber 6 having a hollow structure.

Both the solid single fiber 5 and the hollow single fiber 6 have a thickness of 10
It is a single fiber of, for example, a polyester resin having a size of about 70 μm to 70 μm. The area of the hollow portion 7 of the hollow single fiber 6 is about 40% of the cross-sectional area of the entire fiber, and is about 40% lighter than the solid single fiber 5. Therefore, for example, a solid single fiber 5 having a thickness of 14 mm and a basis weight of 350 g / m 2 is used.
In the comparison between the fiber aggregate of the above and the fiber aggregate of hollow single fibers 6 having a thickness of 14 mm and a basis weight of 350 g / m 2, the former has far fewer fibers than the latter.

An adhesive resin layer 8 having a low melting point (melting point: 110 ° C. to 150 ° C.) is adhered to the surface of the solid single fiber 5 of the polyester resin to form a heat-fusible fiber 9. About 30% by weight of the hollow single fiber 6 (20% to
As shown in FIG. 5, the fibers are mixed from the fiber aggregate 10 having a permeability of, for example, 14 mm in thickness and having a basis weight of 350 g / m 2, in which the fibers intersect in a horizontal direction or a vertical direction and are entangled with each other. A filter 1 is formed. That is, the fiber assembly 10 is placed on a molding table and, as shown in FIG.
Is applied for about 1 minute to 2 minutes, whereby the adhesive resin layer 8 on the surface of the heat-fused fibers 9 is melted, and the fibrous sheet-shaped fibrous filter 1 in which the fibers are heat-sealed at the intersections.
The filter for the ventilation fan 2 is configured by stretching the fibrous filter 1 on a resin frame or the like.

When the fibrous filter 1 is used as a filter for the ventilation fan 2, oil particles and the like contained in the airflow sucked by the fan motor of the ventilation fan 2 are entangled with the solid single fiber 5 and the hollow single fiber 6. Due to the shielding effect of the above, it adheres to the fiber and is collected. Oil particles attached to the fiber
The oil droplets gradually adhere to each other and enlarge to form oil droplets. If the weight of the oil droplet exceeds the adhesive force to the fiber, the oil droplet flows down along the fiber and eventually drops. The collection of non-liquid dust such as oil particles is basically attached to and collected by the solid single fiber 5 and the hollow single fiber 6 due to the shielding effect of the single fiber 5 and the hollow single fiber 6 (see FIG. 3). Filter case). Therefore, the collecting function is enhanced by the solid single fiber 5 and the hollow single fiber 6
The larger the surface area, the better. However, this surface area changes depending on the thickness of the fiber, the surface shape of the fiber, and the number of fibers.

With respect to the fiber assembly 10 having the same weight, the number of fibers and the surface area are larger when only the hollow single fiber 6 is used than when only the solid single fiber 5 is used.
On the other hand, the pressure loss increases. When the weight of the fiber aggregate composed only of the solid single fibers 5 is the same, the number of the fiber aggregates decreases and the pressure loss decreases. FIG. 7 shows that the hollow monofilament 6 and the solid monofilament 5 have a fiber thickness of about 70 μm large, about 40 μm medium, and about 10 μm small.
2 shows the results of examining the pressure loss and the trapping rate of the fiber assembly 10 in each combination in which the percentages are mixed by applying the ordinary ventilation fan 2.

As can be seen from FIG. 7, the combination of large and large results in a fibrous filter 1 having a low pressure loss but a slightly low collection rate, and the combination of medium and medium has a slightly high pressure loss. Filtration filter 1 with good collection rate
In the combination of small and small, the pressure loss is high, but the collection rate is fairly good. Other combinations are as shown in FIG. 7, and the fibrous filter 1 can be constituted by a combination suitable for the equipment to be applied. The disposable filter applied to the ventilation fan 2 may have a performance of a combination of medium and medium.

The advantage of using the hollow single fiber 6 as a constituent fiber of the fibrous filter 1 is that it can be reduced in weight without changing the surface area. When compared with the same type, the material cost is significantly reduced and the weight is reduced. Further, as shown in the first embodiment, the fibers are connected to each other by heat fusion, so that a facility for spraying or dipping the adhesive is not required, and a point-adhesion state is obtained, and clogging due to a thin film of the adhesive is prevented. Since it is not possible, the performance can be improved as well as the cost can be reduced.

The heat-fusible fiber 9 may be formed by applying an adhesive resin layer 8 having a low melting point (melting point: 110 ° C. to 150 ° C.) on the surface of the hollow single fiber 6. The low melting point adhesive resin layer 8 may be applied to both surfaces of the substrate 5. Further, a heat-fused fiber 9 having an adhesive resin layer 8 coated separately from the hollow single fiber 6 and the solid single fiber 5 is formed, and these three fibers are mixed to form a fibrous fiber assembly 10 having air permeability. The filter 1 may be configured. However, although the above-mentioned effect by the heat fusion is not obtained, even if the fibers of the fiber assembly 10 are connected to each other by spraying or dipping the adhesive to form the fibrous filter 1, the use of the hollow monofilament 6 does not result. The above effects can be obtained.

Embodiment 2 In the above-described first embodiment, the fibrous filter 1 is constituted by the fiber aggregate 10 in which the hollow single fibers 6 and the solid single fibers 5 are mixed. You can also. In the second embodiment, the fibrous filter 1 is constituted by a fiber aggregate 10 including only the hollow single fibers 6. When connecting fibers by heat fusion,
As shown in FIG. 8, some of the hollow single fibers 6 are configured as the heat-fused fibers 9 as described in the first embodiment, and these are mixed to form a fiber aggregate 10. The fibrous filter 1 is obtained by the method shown. Thus, the fibrous filter 1 is lighter and requires less material. The other basic functions are the same as those of the first embodiment, and the description thereof is omitted.

Embodiment 3 FIG. The fibrous filter 1 of the third embodiment is a device that improves the performance of the fibrous filter 1 of the first embodiment. The basic configuration other than this is the same as that of the first embodiment. Therefore, the same portions as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The fibrous filter 1 according to the third embodiment also comprises a fiber aggregate 10 of hollow single fibers 6 and solid single fibers 5. The cross-sectional area of the solid portion 12 of the hollow single fiber 6 and the solid single fiber 5 is substantially the same as shown in FIG. 9, and the surface area of the hollow single fiber 6 is larger.
The other configuration is the same as that of the first embodiment. According to the fibrous filter 1 having such a configuration, the trapping performance is improved without increasing the pressure loss. That is, the surface area can be increased without changing the weight (the number of fibers). Other functions and advantages are the same as those of the first embodiment.

Embodiment 4 The fibrous filter 1 of the fourth embodiment is a device that improves the performance of the fibrous filter 1 of the first and second embodiments. The basic configuration other than this is the same as that of the first and second embodiments. Therefore, the same portions as those of the first and second embodiments are denoted by the same reference numerals, and description thereof will be omitted.

The fibrous filter 1 of the fourth embodiment
As shown in FIG. 10, the solid single fiber 5 is a non-circular shaped fiber having a large surface area such as a cross, a star, or a Y in cross section. Thereby, the surface area for collecting oil particles and dust is increased, and the collecting performance is improved. Other configurations, functions, and advantages are the same as those of the first and second embodiments.

[0030]

As apparent from the above description of the embodiment, according to the first aspect of the present invention, it is possible to obtain a light-weight, low-cost, low-cost fibrous filter with low pressure loss.

According to the second aspect of the present invention, a fibrous filter that is lightweight and has low material costs can be obtained.

According to the third aspect of the present invention, it is possible to obtain a fibrous filter which is lightweight, low in material cost, low in cost and low in pressure loss.

According to the fourth aspect of the present invention, a fibrous filter that is lightweight and has low material costs can be obtained.

According to the fifth aspect of the present invention, it is possible to obtain a fibrous filter which is lightweight, low in material cost, low in cost and low in pressure loss.

According to the sixth aspect of the present invention, a fibrous filter suitable for a disposable filter for a ventilation fan can be obtained together with the effects according to the third to fifth aspects.

According to the seventh aspect of the present invention, a low-cost fibrous filter which can easily obtain the function according to the intended use together with the effect according to any one of the third to sixth aspects is obtained.

According to the eighth aspect of the present invention, the trapping ability is improved together with the effect according to any one of the third to sixth aspects.

According to the ninth aspect of the present invention, the trapping ability is improved together with the effect according to any one of the third to eighth aspects.

According to the tenth aspect of the present invention, it is possible to easily produce a light-weight, low-material-cost, low-pressure-loss, fibrous filter.

[Brief description of the drawings]

FIG. 1 is a plan view showing a fibrous filter according to a first embodiment.

FIG. 2 is a perspective view of a ventilation fan to which the fibrous filter according to the first embodiment is applied.

FIG. 3 is a plan view of an air conditioning and ventilation device to which the fibrous filter according to the first embodiment is applied.

FIG. 4 is an enlarged sectional view of a solid single fiber and a hollow single fiber of the fibrous filter of the first embodiment.

FIG. 5 is an enlarged view showing a fiber composition of the fibrous filter of the first embodiment.

FIG. 6 is an explanatory diagram showing a manufacturing process of the fibrous filter of the first embodiment.

FIG. 7 is an explanatory diagram showing performance evaluation of the fibrous filter according to the first embodiment by a combination of fiber thicknesses.

FIG. 8 is an enlarged view showing a fiber composition of a fibrous filter according to a second embodiment.

FIG. 9 is an enlarged sectional view of a solid single fiber and a hollow single fiber of a fibrous filter according to Embodiment 3.

FIG. 10 is an enlarged sectional view showing a solid single fiber of a fibrous filter according to a fourth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Fibrous filter, 5 Solid single fiber, 6 Hollow single fiber, 7 Hollow part, 8 Adhesive resin layer, 9 Heat fusion fiber, 10 Fiber aggregate, 11 Hot air, 12
Enrichment part.

Claims (10)

[Claims] An air-permeable fiber aggregate made of a hollow heat-fused single fiber having a low-melting adhesive resin layer formed on the surface of a hollow single fiber having a hollow structure, and the fibers are thermally fused to each other by the adhesive resin layer. A fibrous filter made by 2. A fibrous filter in which fibers of an air-permeable fiber aggregate made of hollow single fibers having a hollow structure are connected to each other by an adhesive. 3. A hollow single fiber having a hollow structure and a solid single fiber having a solid structure, and a low melting point adhesive resin layer formed on the surface of at least one of the hollow single fiber and the solid single fiber to be heat-fused. A fibrous filter comprising a fiber, and an air-permeable fiber aggregate in which the hollow single fiber and the solid single fiber are mixed, and the fibers are heat-fused with the heat-fusible fiber. 4. A fibrous filter in which fibers of a gas permeable fiber assembly in which hollow single fibers having a hollow structure and solid single fibers having a solid structure are mixed are connected by an adhesive. 5. A fiber assembly obtained by mixing a hollow single fiber having a hollow structure, a solid single fiber having a solid structure, and a heat fusion fiber having a low melting point adhesive resin layer formed on a surface thereof is formed by the heat fusion fiber. A fibrous filter made by fusing fibers to each other. 6. The fibrous filter according to claim 3, wherein the hollow monofilament and the solid monofilament have substantially the same fiber diameter. 7. The fibrous filter according to claim 3, wherein the hollow monofilament and the solid monofilament have different thicknesses. filter. 8. The fibrous filter according to any one of claims 3 to 6, wherein the hollow monofilament and the solid monofilament have substantially the same cross-sectional area in the solid area, A fibrous filter having an outer diameter larger than that of a solid single fiber. 9. The fibrous filter according to claim 3, wherein the solid monofilament is a non-circular shaped fiber having a large surface area such as a cross or a star in cross section. A fibrous filter characterized by comprising. 10. A low melting point adhesive resin layer is formed on at least one surface of a hollow single fiber having a hollow structure and a solid single fiber having a solid structure, and the hollow single fiber and the solid single fiber are mixed to provide air permeability. A method for producing a fibrous filter, comprising: after obtaining a fiber aggregate, heat-treating the fiber aggregate to thermally fuse fibers with each other by the adhesive resin layer.