KR101165829B1 - Method for manufacturing filter cartridge - Google Patents

Abstract

Disclosed is a method for manufacturing a filter cartridge. The disclosed invention comprises the steps of: winding a first nonwoven to form a core; And winding a second nonwoven fabric into the core.

According to the present invention, since the core is manufactured using the composite fiber, the core formed of the plastic injection molding becomes unnecessary, thereby reducing the possibility of secondary contamination by a substance such as a surfactant.

Filters, cores, filter media

Description

Filter cartridge manufacturing method {METHOD FOR MANUFACTURING FILTER CARTRIDGE}

The present invention relates to a filter cartridge manufacturing method, and more particularly, to a filter cartridge manufacturing method for manufacturing a filter cartridge for purifying the fluid by filtering impurities from the fluid.

Since fluids such as water and air are usually contaminated with various particles, in industrial processes, these particles are physically removed and a purified fluid is added thereto. Depth filters are the most commonly used filters for this purpose, and most of the impurities are trapped in the filter internal structure so that the housing does not need to be cleaned when the filter is replaced.

The above-mentioned depth filter may be of various types depending on the material and the manufacturing method, but the most easy of these is the yarn depth filter. Yarn depth filter is a simple filter with a yarn wound on a plastic core to maintain mechanical strength, and is mainly polyester based because the material must be produced in the form of yarn.

However, the yarn depth filter has a severe dropping of the media forming the yarn, foaming may occur due to the surfactant mixed during the production of the yarn, and a water-based solution based on acid or base, in which polyester-based media is widely used industrially Since the filter is likely to be damaged by decomposition, there is a disadvantage of increasing the possibility of secondary contamination by the filter.

An advanced form of the yarn depth filter is a nonwoven laminated filter cartridge. This nonwoven laminated filter cartridge uses a nonwoven fabric produced by a meltblown or felt method, and is a cylindrical filter cartridge manufactured by winding a nonwoven fabric concentrically on a cylindrical core.

According to the nonwoven laminated filter cartridge according to the prior art as described above, the core is formed of a plastic injection molding. Accordingly, the core manufacturing process is required separately from the filter cartridge manufacturing process. On the contrary, even if a separately manufactured core is purchased and used, there is a hassle in handling and storing the core so that the core is not contaminated until the filter cartridge is manufactured so that secondary contamination by the filter cartridge does not occur.

In addition, since the surfactant is used in the separation process from the mold during core manufacturing, the nonwoven fabric filter cartridge according to the prior art uses a core that is likely to be contaminated by such a surfactant, so that secondary contamination by the filter cartridge is prevented. There is a problem that increases the likelihood of occurrence. Therefore, there is a need to improve this.

The present invention has been made to improve the problems of the prior art as described above, and a filter cartridge manufacturing method capable of manufacturing a filter cartridge with a low risk of secondary contamination by the filter cartridge without using a core formed of a plastic injection molding The purpose is to provide.

A filter cartridge manufacturing method according to an aspect of the present invention includes: winding a first nonwoven fabric to form a core; And winding a second nonwoven fabric on the core.

Here, the first nonwoven fabric is preferably formed of a composite fiber made of two or more resin components having different melting points.

In addition, the composite fiber is preferably formed such that a high melting point resin is disposed inside and a low melting point resin is disposed outside.

In the forming of the core, the core may be wound while heating the first nonwoven fabric to a temperature between a melting point of the high melting point resin and a melting point of the low melting point resin.

In the forming of the core, it is preferable to wind the first nonwoven fabric at a rapid speed.

In addition, the second nonwoven fabric is preferably formed of a melt blown thermoplastic fiber.

In addition, the filter cartridge manufacturing method according to an aspect of the present invention comprises the steps of: winding the first nonwoven fabric to form a core; And laminating a second nonwoven fabric and a third nonwoven fabric on the core.

Here, it is preferable that the first nonwoven fabric and the third nonwoven fabric are formed of a composite fiber composed of two or more resin components having different melting points.

In addition, the composite fiber is preferably formed such that a high melting point resin is disposed inside and a low melting point resin is disposed outside.

In the forming of the core, the core may be wound while heating the first nonwoven fabric to a temperature between a melting point of the high melting point resin and a melting point of the low melting point resin.

Further, the step of laminating the second nonwoven fabric and the third nonwoven fabric and winding the core may include heating the second nonwoven fabric and the third nonwoven fabric to a temperature between the melting point of the high melting point resin and the melting point of the low melting point resin. It is preferable to heat.

In addition, in the step of laminating the second nonwoven fabric and the third nonwoven fabric and winding the core, it is preferable to wind the second nonwoven fabric and the third nonwoven fabric at a rapid speed.

In addition, in the step of laminating the second nonwoven fabric and the third nonwoven fabric and winding the core, it is preferable that the second nonwoven fabric and the third nonwoven fabric are gradually heated to a low temperature.

In addition, the second nonwoven fabric is preferably formed of a melt blown thermoplastic fiber.

In addition, the filter cartridge manufacturing method according to another aspect of the present invention comprises the steps of: winding the first nonwoven fabric to form a core; And winding up a second nonwoven fabric formed to be corrugated to the core.

According to the filter cartridge manufacturing method of the present invention, unlike the prior art, since the core is manufactured using a composite fiber, the core formed of a plastic injection molding is unnecessary, thereby reducing the possibility of secondary contamination by a substance such as a surfactant.

In addition, since the present invention continuously manufactures the core and the filter medium using a similar process in the same production line, there is no need for a separate manufacturing process for the core manufacturing and handling and storage of the manufactured core, thereby improving production efficiency.

In addition, the present invention can form a density gradient in the filter cartridge in the filter cartridge manufacturing process, without a separate device or cumbersome work, it is possible to improve the production efficiency, it is possible to improve the filtration performance of the filter cartridge.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of a filter cartridge manufacturing method according to the present invention. For convenience of explanation, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation. In addition, the terms described below are defined in consideration of the functions of the present invention, which may vary depending on the intention or custom of the user, the operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

1 is a perspective view showing a filter cartridge manufactured by a filter cartridge manufacturing method according to an embodiment of the present invention, Figure 2 is a flow chart for explaining a filter cartridge manufacturing method according to an embodiment of the present invention, Figure 3 2 is a flowchart for explaining the core forming step shown in FIG. 2, FIG. 4 is a diagram for illustrating the internal structure of the first nonwoven fabric, and FIG. 5 is a flowchart for explaining the filter medium forming step shown in FIG.

According to the filter cartridge manufacturing method according to an embodiment of the present invention, as shown in Figures 1 to 5, first to form a core 10 (S10). The core 10 can be formed by winding the first nonwoven fabric 15.

The first nonwoven fabric 15 is formed of a composite fiber (11). The composite fiber 11 is composed of two or more resin components having different melting points. The composite fiber 11 is preferably a core-sheath type composite fiber formed such that the high melting point resin 12 is disposed inside and the low melting point resin 13 is disposed outside.

As an example of such a composite fiber 15, a superfiber composite fiber in which a polypropylene resin is arranged inside and a polyethylene resin is arranged outside is illustrated in this embodiment. According to the composite fiber 11, since the melting point of the polypropylene resin is about 160 ° C and the melting point of the polyethylene resin is about 120 ° C, the melting point difference between the inside and the outside is about 40 ° C.

However, the composite fiber 11 applied to the present invention is not limited thereto, and may be formed of various high melting point resins 12 and low melting point resins 13. As examples of the high melting point resin 12 and the low melting point resin 13, in addition to polypropylene and polyethylene, poly-4methylpentene, a crystalline copolymer of propylene with other alpha olefins, polyethylene terephthalate, polybutylene tere And thermoplastic resins such as phthalate, polyamide, and polycarbonate. Among these, composite fibers selected and combined are selected so that the melting point difference between the high melting point resin and the low melting point resin is 10 ° C or higher, preferably 15 ° C or higher.

Of course, as long as it does not interfere with the effect of the present invention, the composite fiber may be made of three or more resins. In the case of the resin having no melting point, the flow start temperature is regarded as the melting point.

The first nonwoven fabric 15 made of such a composite fiber 11 is wound on a winding rod while being heated (S11) (S13). The first nonwoven fabric 15 may be heated by a separate heating means, for example, a hot fan radiating hot air, a heating roll, or a far infrared heater, or may be heated by a self-heating winding rod.

At this time, the first nonwoven fabric 15 is heated to a temperature between the melting point of the high melting point resin 12 and the melting point of the low melting point resin 13. When the high melting point resin 12 is a polypropylene resin and the low melting point resin 13 is a polyethylene resin, it is preferable to heat the first nonwoven fabric 15 to about 130 to 150 ° C. At this time, the heating and winding process is not necessarily to be performed in the order described above, it turns out that the order may be reversed each other, and may be performed at the same time.

As such, when the first nonwoven fabric 15 is wound on the winding rod while heating the first nonwoven fabric 15, the first nonwoven fabric 15 is wound in layers in a concentric shape, and the interlayers are completely heat-sealed. Specifically,

When the first nonwoven fabric 15 is wound on the winding rod while heating, the low melting resin 13 disposed on the outer side of the composite fiber 11 forming the first nonwoven fabric 15 is melted so that a part thereof penetrates into the adjacent layer. As the low melting point resin 13 soaked in the adjacent layer is cooled, the adjacent nonwoven layers 15 are wound together to form a concentric circular layer. As such, the first nonwoven fabric 15 in which the adjacent layers are fused together is completely fused in its entirety, thereby completing the formation of the core 10.

At this time, while adjusting the tension of the first nonwoven fabric 15 so that the first nonwoven fabric 15 maintains an appropriate tension, the first nonwoven fabric 15 is consolidated by consolidating the first nonwoven fabric 15 using a heating roll or the like. In the process of winding, heat fusion can be more effective.

In the above process, the density gradient may be formed in the core 10 by variably adjusting at least one of the heating temperature and the winding speed of the first nonwoven fabric 15.

In order to form a density gradient in the core 10 by variably adjusting the heating temperature, the first nonwoven fabric 15 is wound up and gradually heated to a lower temperature (S12). And, if you want to form a density gradient in the core 10 by varying the winding speed, the first nonwoven fabric 15 is wound up at a rapid speed while heating (S14). And this variable adjustment may be made in a manner that simultaneously variable control both the winding speed and heating temperature.

The composite fiber 11 which forms the 1st nonwoven fabric 15 becomes small in diameter, as the low melting resin 13 melts by heating. That is, the composite fiber 11 is to change the diameter in accordance with the degree of melting of the low melting point resin (13).

According to the present embodiment, a density gradient is formed in the core 10 by controlling the melting degree of the low melting point resin 13 by variably adjusting at least one of the heating temperature and the winding speed of the first nonwoven fabric 15 as described above. do. Specifically,

In the process of winding the first nonwoven fabric 15, the first nonwoven fabric 15 is gradually heated to a low temperature, or the first nonwoven fabric 15 is gradually wound up at a high speed while the first nonwoven fabric 15 is heated, or both In parallel, the low melting point resin 13 is melted relatively much in the initial stage of the winding, and the low melting point resin 13 is gradually melted as the winding proceeds. Accordingly, the core 10 has a density gradient in which the composite fibers 11 having a relatively small diameter are densely arranged toward the inside, and the composite fibers 11 having a relatively large diameter are relatively sparsely arranged toward the outside. Will have

When the core 10 is formed, the filter medium 20 is formed (S20). The filter medium 20 can be formed by winding a 2nd nonwoven fabric (symbol abbreviation) and a 3rd nonwoven fabric (symbol abbreviation).

The second nonwoven is formed of melt blown thermoplastic fibers. The melt blown fiber used in this embodiment is a fiber obtained by the melt blown method. The melt blow method is a method of spraying a thermoplastic resin extruded and melted from a spinneret with a high-speed gas sprayed around a spinneret to spray a collecting conveyor net or the like to obtain a fibrous web. US Pat. No. 3,532,800.

Examples of the thermoplastic fibers used in this embodiment include polypropylene, low density polyethylene, high density polyethylene, linear low density polyethylene and copolymerized polypropylene (for example, ethylene and butene-1,4-methylpentene-based propylene). Polyester resins such as polyolefin resins such as binary or polymembered copolymers including 1), polyethylene terephthalate, polybutylene terephthalate and these low melting polyesters copolymerized by adding isophthalic acid in addition to terephthalic acid as an acid component. Thermoplastic resins such as polyamide-based resins such as nylon 6 and nylon 66, polystyrene-based resins (atactic polystyrene and syndiotactic polystyrene), polyurethane elastomers, polyester elastomers and polytetrafluoroethylene have. Moreover, functional resins, such as making a filter cartridge biodegradable using biodegradable resins, such as lactic acid-type polyester, can be used.

In addition, when using a resin which can be polymerized with a metallocene catalyst such as polyolefin resin or polystyrene resin, when the resin polymerized with a metallocene catalyst is used, the strength of the nonwoven fabric is improved, the chemical resistance is improved, and the production energy is increased. The properties of the metallocene resin, such as reduction, are preferred because they survive in the filter cartridge. Moreover, in order to adjust the heat adhesiveness and rigidity of a long fiber nonwoven fabric, these resin can be mix | blended and used. Among these, when the filter cartridge is used for filtration of an aqueous solution at room temperature, polyolefin resins including polypropylene are preferable in terms of chemical resistance and cost, and when used in relatively high temperature liquids, polyester resins, polyamide resins or Syndiotactic polystyrene resins are preferred.

The third nonwoven fabric is formed of a composite fiber like the first nonwoven fabric. In this case, the third nonwoven fabric may be formed of the same composite fiber as the composite fiber forming the first nonwoven fabric, or may be formed of a composite fiber different from the composite fiber forming the first nonwoven fabric.

Since the average fiber diameter of the composite fiber and melt blown fiber used for a present Example differs according to the use of a filter cartridge or the kind of resin, it is difficult to prescribe uniformly, but the range of 0.5-1000 micrometers is preferable. When the fineness is less than 0.5 μm, it is theoretically possible to use the filter cartridge of this embodiment, but in reality, manufacturing is difficult. On the other hand, when a fiber diameter exceeds 1000 micrometers, when using it as a nonwoven fabric later, a nonuniformity may arise in a fiber diameter and the quality of a nonwoven fabric. In addition, when the average fiber diameter exceeds 50 m, adjacent fibers may be fused together, but there is no particular problem as long as the fiber does not interfere with the effects of the present invention.

The second nonwoven fabric and the third nonwoven fabric as described above are wound on the core 10 while being laminated (S21) and heated (S23). In this case, the lamination, heating, and winding processes are not necessarily performed in the above-described order, the order may be reversed, or may be simultaneously performed.

And the heating process, as in the core 10 forming process, may be heated by a separate heating means, for example, a hot fan radiating hot air or a heating roll or far-infrared heater, or the like, may be heated by a self-heating winding rod. It may be.

At this time, the laminated second nonwoven fabric and the third nonwoven fabric are heated to a temperature between the melting point of the high melting point resin (not shown) of the third nonwoven fabric and the melting point of the low melting point resin (not shown).

Here, in the case of selecting the same material formed of the same composite fiber as the first nonwoven fabric as the third nonwoven fabric, in addition to the advantage that the core 10 and the filter medium 20 can be formed using the same nonwoven fabric in the process of forming the filter medium 20 When heating and winding the heating temperature control and the winding speed control degree can be taken similarly to the core 10 forming process, there is an advantage that the process of forming the filter medium 20 can be more easily performed.

On the contrary, when the third nonwoven fabric is selected from the composite fibers forming the first nonwoven fabric and different composite fibers, the melting point difference between the high melting point resin and the low melting point resin is 10 ° C. or higher, preferably as in the core forming step. Adopt composite fiber selected and combined to be 15 ℃ or more. Then, during heating and winding, heating temperature control and winding speed are appropriately adjusted according to the characteristics of the composite fiber.

As described above, when the second nonwoven fabric and the third nonwoven fabric are wound on the core 10 while being laminated and heated, the laminate of the second nonwoven fabric and the third nonwoven fabric is wound in layers in a concentric manner, and in the process, the second nonwoven fabric and the third nonwoven fabric are wound. The interlayer between the nonwoven fabric and the third nonwoven fabric and the laminate of the second nonwoven fabric and the third nonwoven fabric is completely heat-sealed. Specifically,

That is, when the laminate of the second nonwoven fabric and the third nonwoven fabric is wound on the core 10 while heating, the low melting point resin disposed outside the composite fiber forming the third nonwoven fabric is melted, and a portion thereof is the second layer of the adjacent layer. As the low melting resin penetrates into the nonwoven fabric and the low melting point resin soaks into the adjacent layer is cooled, the laminates of the second nonwoven fabric and the third nonwoven fabric wound in a concentric circular layer are fused to each adjacent layer. At this time, a part of the low melting point resin is also immersed in the second nonwoven fabric forming one layer and then cooled, and the second nonwoven fabric and the third nonwoven fabric forming one layer are also fused together. As a result, the laminate of the second nonwoven fabric and the third nonwoven fabric is completely fused in its entirety, and the formation of the filter medium 20 is completed.

At this time, as in the process of forming the core 10, while adjusting the tension of the laminate of the second nonwoven fabric and the third nonwoven fabric so that the laminate of the second nonwoven fabric and the third nonwoven fabric maintain a proper tension, using a heating roll or the like When the laminate of the second nonwoven fabric and the third nonwoven fabric is consolidated, heat fusion can be more effectively performed in the process of winding up the laminate of the second nonwoven fabric and the third nonwoven fabric.

In the above process, the density gradient may be formed in the filter medium 20 by variably adjusting at least one of the heating temperature and the winding speed of the laminate of the second nonwoven fabric and the third nonwoven fabric. Since this process has already been described in the core 10 formation process, a detailed description thereof will be omitted here.

The filter cartridge manufacturing method of this embodiment forms a density gradient in the filter cartridge 30 by a method as described above, without a separate device or cumbersome work, thereby improving production efficiency, and It can greatly improve the service life and filtration performance.

Due to the density gradient formed in the filter cartridge 30, the filter cartridge 30 filters relatively large impurity particles in the outer portion having a low density, and filters smaller and smaller impurity particles toward the inner side, so that the life and filtration performance are greatly increased. Is improved.

The porosity of the filter cartridge 30 of the present embodiment formed by the above process is preferably in the range of 65 to 85%. If the porosity is smaller than 65%, the fiber density becomes too high, so the liquid permeability is lowered. On the contrary, when such a value is larger than 85%, the strength of the filter cartridge is lowered and problems such as deformation of the filter cartridge when the filtration pressure is high tends to occur. The porosity can be appropriately adjusted by adjusting the degree of thermal fusion or by tensioning the laminate of the second nonwoven fabric and the third nonwoven fabric at the time of winding.

When the formation of the filter medium 20 is completed as described above, the filter cartridge 30 is subjected to a post-processing process such as a finishing process of both ends of the filter medium 20 by a process such as cutting to a predetermined size, heat treatment, adhesion, and thermal bonding. Complete the manufacture of (S30).

The filter cartridge manufacturing method of this embodiment as described above provides the following effects.

First, since the core 10 is manufactured using the composite fiber, since the core formed of a plastic injection molding is unnecessary, there is an effect of greatly reducing the possibility of secondary contamination by a material such as a surfactant.

Second, since the core 10 and the filter medium 20 are continuously manufactured using a similar process in the same production line, there is no need for a separate manufacturing process and the handling and storage of the manufactured core for the core 10 production, The production efficiency is improved.

Third, in the manufacturing process of the filter cartridge 30, it is possible to form a density gradient in the filter cartridge 30 without a separate device or cumbersome work, thereby improving the production efficiency, while greatly improving the filtration performance of the filter cartridge 30 There is an effect that can be improved.

In the present embodiment described above, a process of forming the filter medium 20 using the second nonwoven fabric and the third nonwoven fabric, that is, two types of nonwoven fabrics is illustrated, but is not limited thereto. In the present invention, in the process of forming the filter medium, only one of the second nonwoven fabric and the third nonwoven fabric may be used, and in addition to the second nonwoven fabric and the third nonwoven fabric, another nonwoven fabric may be added to use three or more kinds of nonwoven fabrics. Modifications are possible.

On the other hand, the filter cartridge manufacturing method as described above is only one embodiment of the present invention, there may be a number of other embodiments.

Figure 6 is a side view showing a part of the filter cartridge manufactured by the filter cartridge manufacturing method according to another embodiment of the present invention, Figure 7 is a flow chart illustrating a filter cartridge manufacturing method according to another embodiment of the present invention. 8 is a flowchart for explaining a filter medium forming step shown in FIG. 7.

According to the filter cartridge manufacturing method according to another embodiment of the present invention, as shown in Figures 6 to 8, first to form a core 40 (S40). The core 40 can be formed by winding the first nonwoven fabric 15 (see FIG. 4). Since the process of forming the core 40 is the same as the process of forming the core (S10; see FIG. 2) according to an embodiment of the present invention, a detailed description thereof will be omitted.

When the process of forming the core 40 is completed, the filter medium 50 is formed (S50). The filter medium 50 is formed using a second nonwoven fabric. In the present embodiment, the second nonwoven fabric is the same as the second nonwoven fabric used in the embodiment of the present invention. In order to form the filter medium 50, first, pleats are formed on the second nonwoven fabric (S51). Then, by winding the second nonwoven fabric having a pleat formed on the core 40 (S53), the filter medium 50 is completed.

After completing the formation of the core 30 and the filter medium 50 as described above, the combination of the core 30 and the filter medium 50 is accommodated in the housing 60 formed of a plastic material, etc., both ends of the housing 60 Seal with a cap (70). At this time, both ends of the combination of the core 30 and the filter medium 50 should be completely sealed by the cap (70). At this time, the sealing method may be applied, such as heat treatment, adhesion, thermal bonding.

According to the above process, the manufacture of the filter cartridge 80 is completed (S60), and the completed filter cartridge 80 is manufactured as a pleat type filter cartridge.

The filter cartridge 80 manufactured by the filter cartridge manufacturing method of the present embodiment is formed by the filter manufacturing method according to an embodiment of the present invention by forming the filter medium 50 as described above. Compared with the filter cartridge 30 (see FIG. 1), it provides the effect of greatly widening the filtration area.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. I will understand. Accordingly, the true scope of protection of the present invention should be defined by the following claims.

1 is a perspective view showing a filter cartridge manufactured by a filter cartridge manufacturing method according to an embodiment of the present invention.

2 is a flowchart illustrating a filter cartridge manufacturing method according to an embodiment of the present invention.

FIG. 3 is a flowchart for explaining a core forming step illustrated in FIG. 2.

4 is a view for showing the internal structure of the first nonwoven fabric.

FIG. 5 is a flowchart for explaining the filter medium forming step illustrated in FIG. 2.

6 is a side view showing a part of the filter cartridge manufactured by the filter cartridge manufacturing method according to another embodiment of the present invention.

7 is a flowchart illustrating a filter cartridge manufacturing method according to another embodiment of the present invention.

FIG. 8 is a flowchart for explaining the filter medium forming step illustrated in FIG. 7.

Description of the Related Art [0002]

10,40: core 11: composite fiber

12: high melting point resin 13: low melting point resin

15: first nonwoven fabric 20,50: filter medium

30,80: Filter Cartridge

Claims (15)

Winding the first nonwoven to form a core; And And winding a second nonwoven fabric on the core. The first nonwoven fabric is formed of a composite fiber composed of two or more resin components having different melting points, and the composite fiber is formed such that a high melting point resin is disposed inside and a low melting point resin is disposed outside. The forming of the core may include varying the heating temperature of the first nonwoven fabric such that the melting amount per unit time of the low melting point resin decreases as the winding progresses compared to the initial winding, or the first nonwoven fabric is heated while heating the first nonwoven fabric. The method of manufacturing a filter cartridge, characterized in that for varying the winding speed of the variable, or variable heating temperature and winding speed of the first nonwoven fabric while heating the first nonwoven fabric. delete delete The method of claim 1, The forming of the core may include winding the first nonwoven fabric at a temperature between a melting point of the high melting point resin and a melting point of the low melting point resin. 5. The method of claim 4, The forming of the core may include winding the first nonwoven fabric at a high speed while heating the first nonwoven fabric. The method of claim 1, And the second nonwoven fabric is formed of a melt blown thermoplastic fiber. Winding the first nonwoven to form a core; And Stacking a second nonwoven fabric and a third nonwoven fabric on the core; The first nonwoven fabric and the third nonwoven fabric are formed of a composite fiber composed of two or more resin components having different melting points, and the composite fiber is formed such that a high melting point resin is disposed inside and a low melting point resin is disposed outside. , The forming of the core may include varying the heating temperature of the first nonwoven fabric such that the melting amount per unit time of the low melting point resin decreases as the winding progresses compared to the initial winding, or the first nonwoven fabric is heated while heating the first nonwoven fabric. The method of manufacturing a filter cartridge, characterized in that for varying the winding speed of the variable, or variable heating temperature and winding speed of the first nonwoven fabric while heating the first nonwoven fabric. delete delete The method of claim 7, wherein The forming of the core may include winding the first nonwoven fabric at a temperature between a melting point of the high melting point resin and a melting point of the low melting point resin. The method of claim 7, wherein The step of laminating the second nonwoven fabric and the third nonwoven fabric and winding the core may include winding the second nonwoven fabric and the third nonwoven fabric while heating to a temperature between a melting point of the high melting point resin and a melting point of the low melting point resin. Filter cartridge manufacturing method characterized in that. 12. The method of claim 11, The step of laminating the second nonwoven fabric and the third nonwoven fabric and winding the core may include winding the second nonwoven fabric and the third nonwoven fabric at a high speed while heating the second nonwoven fabric and the third nonwoven fabric. Filter cartridge manufacturing method. 12. The method of claim 11, And laminating the second nonwoven fabric and the third nonwoven fabric to the core and heating the second nonwoven fabric and the third nonwoven fabric to a lower temperature. The method of claim 7, wherein And the second nonwoven fabric is formed of a melt blown thermoplastic fiber. delete

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