CN114130117A

CN114130117A - Filter medium

Info

Publication number: CN114130117A
Application number: CN202010910450.XA
Authority: CN
Inventors: 贾建东; 杨印景
Original assignee: Hangzhou Kebaite Technology Co ltd
Current assignee: Hangzhou Kebaite Technology Co ltd
Priority date: 2020-09-02
Filing date: 2020-09-02
Publication date: 2022-03-04
Anticipated expiration: 2040-09-02
Also published as: CN114130117B

Abstract

The invention relates to a filter medium, which comprises an adsorptive particle layer and a non-woven fabric supporting layer, wherein the adsorptive particle layer comprises fibers and active particles, and is characterized in that: the composite fiber of the skin-core structure is formed by the binder and the fibers, the binder is used as a skin layer of the composite fiber, the fibers are used as a core layer of the composite fiber, a bonding region is formed on the surface of the active particle by the binder, the surface of the active particle further comprises an active region, and the area ratio of the bonding region to the active region is within the range of 1: 200-1: 50. The object of the invention is to provide a filter medium with active particles which have a self-binding effect.

Description

Filter medium

Technical Field

The invention relates to a filter medium, in particular to a filter medium with active particles.

Background

The air filter is a device capable of filtering and purifying air, has wide application, and can be generally used for cleaning workshops, factory buildings, or cleaning operating rooms, or for dust prevention of electronic mechanical communication equipment. Many industrial plants produce precision products in an industrial process, which often requires the production plant to be kept clean, and thus requires the air entering the clean plant to be filtered. In many laboratories, a precise test operation is performed by placing test equipment in a clean room so that test results are not affected by impurities or dust in the air, and thus the internal environment of the clean room must be strictly controlled.

In the patent document publication No. US6024782, a layered gas filtration medium is disclosed, which comprises an adhesive layer, a substrate and an adsorbent layer, one side of the adsorbent layer being bonded to the adhesive layer and the other side of the adsorbent layer being bonded to another adhesive layer, and so on, to form a filtration medium of a multilayer structure, wherein the substrate provides the support. This patent only constitutes gas filter medium through the adhesive action of bonding layer and adsorbent layer, so can adjust filter medium's density through the density that sets up the adsorbent layer, and then can adjust filter material's pressure drop.

The existing air filter usually uses active adsorption substances to meet different filtering requirements, but the schemes still have some problems which cannot be overcome, for example, the active adsorption substances are difficult to fix and easy to fall off from the filtering medium, thereby reducing the filtering effect of the air filter.

Disclosure of Invention

The object of the invention is to provide a filter medium with active particles which have a self-binding effect.

In order to achieve the purpose, the invention adopts the following technical scheme: a filter media comprising an adsorptive particle layer and a non-woven support layer, the adsorptive particle layer comprising fibers and active particles, characterized in that: the composite fiber of the skin-core structure is formed by the binder and the fibers, the binder is used as a skin layer of the composite fiber, the fibers are used as a core layer of the composite fiber, a bonding region is formed on the surface of the active particle by the binder, the surface of the active particle further comprises an active region, and the area ratio of the bonding region to the active region is within the range of 1: 200-1: 50.

The filter medium comprises an adsorptive particle layer and a non-woven fabric supporting layer, wherein the adsorptive particle layer comprises active particles and fibers, the filter medium also comprises a binder, and the binder and the fibers jointly form composite fibers of a sheath-core structure, wherein the binder forms bonding areas on the surfaces of the active particles, and the parts of the surfaces of the active particles, which are not formed with the bonding areas, are active areas. The active region has adsorptive filtration and the bonded region has bonding, but the bonded region has lost some or all of the adsorptive filtration function. So design, when forming the adsorptivity grained layer with active particle bonding to the fibre, can guarantee the filtering capability of adsorptivity grained layer again. Furthermore, the bonded regions of the active particles can also bond the layer of adsorbent particles to the nonwoven support layer, resulting in a robust and strong filter medium. The fibers in the adsorptive particle layer can play a role in reinforcing and toughening, and as shown in a mechanism diagram of a fiber reinforced adsorptive particle layer in fig. 1, stress acting on the active particles 1 can be transmitted to the active particles 1 and the fibers 2 through the fibers 2, so that the stress is dispersed, and macroscopically, the stress is shown as the strength of the filter medium is improved. In order to not influence the adsorption and filtration effects of active particles, ensure the filtration effect of the filter medium and the bonding effect of the active particles, the area ratio of the bonding area on the surface of the active particles to the active area is within the range of 1: 200-1: 50. The area ratio of the bonding region to the active region of the active particle as referred to herein means the area ratio thereof on the surface of the active particle and does not include the area of the internal pores of the active particle.

Further, the bonded region includes at least three bond points.

The bonding area has at least three bonding point, so the design guarantees that active particle can be firm fixed in filter media, avoids appearing the phenomenon that active particle drops from filter media. It should be noted that, taking a sample of (10 × 10) mm of the filter medium, the active particle surface in the sample is measured to have at least three bonding points, and because the filter medium has a certain consistency, the active particle surface contained in the whole filter medium material can be considered to have at least three bonding points. The sum of the areas of said bond points is equal to the total area of the bond areas.

Further, the diameter z of the fiber and the diameter x of the active particles satisfy: x/z is more than or equal to 20 and less than or equal to 70.

If the contact surface of the active particles and the fibers is a point, the influence of the fibers on the adsorption performance of the active particles can be greatly reduced. If the ratio x/z between the diameter x of the active particles and the diameter z of the fibers is less than 20, the contact between the fibers and the active particles can be expanded into a surface, and the adsorption effect of the active particles is influenced; or x/z is more than 70, the diameter of the active particles is larger than that of the fibers, the bonding effect of the active particles is influenced, and the active particles are easy to separate from the fibers. When the x/z is more than or equal to 20 and less than or equal to 70, the bonding strength and the adsorption and filtration effects of the active particles are balanced, and the effect is optimal.

Further, the bonding region bonds the layer of adsorbent particles to the nonwoven support layer.

The active particles are bonded to the fibers through the bonding areas, and after the adsorptive particle layer is formed, the active particles are further bonded to the non-woven fabric supporting layer through the viscosity of the bonding areas to form the filter medium. So design, when active particle and fibre bond each other and form the adsorptivity grained layer, can form filter media on the adsorptivity grained layer with the adhesion of non-woven fabrics supporting layer again, when having simplified filter media's production and manufacturing technology step, strengthened filter media's bonding effect again.

Further, the absorbent particle layer further comprises a glue powder, the bonding region further comprises a first bonding region, and the glue powder is thermally melted to form the first bonding region.

The glue powder forms a first bonding area on the surface of the active particles, and the bonding effect of the active particles is provided by the bonding agent and the glue powder. So design, can guarantee active particle's bonding effect, with the more firm filtration medium that bonds to fibre and non-woven fabrics supporting layer of high strength of active particle on.

Further, the melting point of the binder is at least 20 ℃ lower than the melting point of the fibers.

In the present invention, the binder is heated to form a bonding region on the surface of the active particles, and the melting point of the binder is 20 ℃ lower than that of the fibers. So design, when heating filter media, when guaranteeing that the binder softens and produce the adhesive action, can guarantee again that fibrous structure and performance can not receive the influence. It should be noted that the term "the binder is melted by heat to form bonding areas on the surfaces of the active particles" in the present invention means that the binder is heated to generate viscosity, so that the active particles are bonded to the fibers, and the bonding areas are formed at the contact positions of the active particles and the fibers, and the binder does not generate viscous flow. This explanation applies throughout.

Further, the material of the binder is selected from one of polyethylene and polypropylene, and the material of the fiber is selected from one of polyethylene terephthalate, polytrimethylene terephthalate and polybutylene terephthalate.

The binder and the fiber form the composite fiber with a skin-core structure, and the materials of the binder and the fiber are selected so as to realize that a bonding area is formed on the surface of the active particle after the binder is melted by heat and be beneficial to the forming processing of the composite fiber. Moreover, the raw materials are low in price, so that the product cost can be reduced.

Further, the fiber comprises long fiber and short fiber, and the length x of the long fiber satisfies the following conditions: x is more than or equal to 30mm, and the length y of the short fiber satisfies the following conditions: y is less than or equal to 25 mm.

Taking a sample of (10 × 10) mm, it was determined that the fibers contained in the sample included long fibers having a length of 30mm or more and short fibers having a length of 25mm or less, and it is considered that the fibers in the filter medium also included long fibers having a length of 30mm or more and short fibers having a length of 25mm or less because the filter medium of the present invention had uniformity and consistency. In the invention, the fibers and the active particles on the filter medium are uniformly distributed, and the fibers in unit length are bonded with a certain quantity of the active particles, so that the active particles bonded on long fibers are much shorter than those on short fibers. As shown in the schematic mechanism diagram of fig. 1, when the filter medium is subjected to a tensile force or a compressive force, the stress acting on the active particles 1 is transmitted to the fibers 2 and then transmitted to other active particles 1 through the fibers, so that the stress can be dispersed and the strength and toughness of the filter medium can be increased. In this case, the long fibers having many active particles bonded thereto are subjected to a relatively small force, and are more likely to break, which may cause breakage of the entire active particle layer in a serious case. In addition, the bonding point of short fiber and other fibers is few, and is more flexible, and when the filter medium receives stress, the short fiber can drive the active particles to slide on the adsorptive particle layer to avoid uneven stress, and the strength and the toughness of the filter medium are kept. Therefore, the long fibers and the short fibers arranged in the filter medium can realize the mixing of multi-scale fibers, and can better toughen and strengthen the filter medium

In another aspect, the present invention provides a method for manufacturing a filter medium, comprising the steps of:

s1: uniformly scattering a first adsorptive particle layer on the surface of the non-woven fabric support layer;

s2: laying composite fibers of a sheath-core structure on the surface of the first absorbent particle layer

Scattering a second adsorptive particle layer on the surface of the composite fiber to form a semi-finished product;

wherein the volume ratio of the skin layer to the core layer of the composite fiber is within the range of 1: 10-10: 1;

s3: heating the semi-finished product to 100-200 ℃, and controlling the heating time within the range of 1-10 min;

s4: laying a non-woven fabric support layer on the second adsorptive particle layer and allowing the non-woven fabric support layer to pass through 150-240 parts of the second adsorptive particle layer

Hot-pressing by a hot roller at the temperature of DEG C;

s5: cooling to obtain the filter medium.

When the filter medium is prepared, the first adsorptive particle layer is firstly scattered on the non-woven fabric supporting layer, then the composite fibers are paved on the first adsorptive particle layer, finally the non-woven fabric supporting layer is paved on the semi-finished product, and the filter medium is formed through hot roller processing. The composite fiber is softened after the step of S3 to generate stickiness, and when the active particles come into contact with the composite fiber, a bonding region is formed on the surface of the active particles, and a portion where the bonding region is not formed still has an adsorption property, which is called an active region. As an improvement of the invention, in order to ensure the bonding effect and the adsorption effect of the active particles, the volume ratio of the skin layer to the core layer of the composite fiber with the skin-core structure is within the range of 1: 10-10: 1. By the selection, after the cortex of the composite fiber is heated to generate viscosity, the area ratio of the bonding area to the active area on the surface of the active particle is within the range of 1: 200-1: 50. If the volume ratio of the skin layer to the core layer of the composite fiber is less than 1:10, the area ratio of the bonding area on the surface of the active particle to the active area is less than 1:200, at the moment, the bonding area is too small, the bonding effect of the active particle is poor, the active particle and the fiber cannot be well bonded together, even the active particle falls off from the filter medium, and the adsorption and filtration effect of the filter medium is seriously influenced; if the volume ratio of the skin layer to the core layer of the composite fiber is more than 10:1, in order to soften the cortex evenly and form the bonding area on the surface of the active particle, then need higher temperature or longer time of heating, more importantly, the area ratio of the bonding area on the surface of the active particle and the active area will be more than 1:50, resulting in an active zone area with adsorptive filtration function that is too small, macroscopically manifested as a reduction in filtration capacity of the filter media.

Further, the step of S2 may be repeated a plurality of times.

So, can be when guaranteeing filter medium bonding strength, increase the thickness of the adsorptivity grained layer in the filter medium, increase filter medium's adsorption filtration effect.

Further, the first layer of adsorbent particles and/or the second layer of adsorbent particles contain a gum powder.

The first and/or second layer of adsorbent particles contain a gum powder. So design, can further guarantee the adhesive strength of adsorptivity grained layer and non-woven fabrics supporting layer among the filter media.

Further, the step S1 includes preheating to 100-150 ℃ for 1-10 min.

So design, can preheat non-woven fabrics supporting layer and first adsorbability grained layer, in the heating step of follow-up, guarantee that the product is even to be heated, guarantee because of the heating effect and produce the formation of the bonding region of bonding effect on the active particle surface, and then guarantee bonding strength between adsorbability grained layer and the non-woven fabrics supporting layer.

Further, there is a Sa step between the steps S2 and S3,

sa: and melt-blowing the glue blocks into glue threads onto the fiber felt through a hot melt glue machine, wherein the diameter of the glue threads is 10-50 mu m, the glue blocks are selected from one or more of polyolefin, EVA and polyurethane, and the heating temperature of the S3 step is 100-160 ℃.

In this way, the bonding strength of the filter medium is provided by the viscosity of the fiber felt and the glue thread, and the bonding effect of the filter medium is increased.

Drawings

The invention will be further described with reference to the accompanying drawings in which:

FIG. 1 is a schematic illustration of the mechanism of fiber reinforced adsorbent particles;

FIG. 2 is a schematic cross-sectional view of a filter media according to a first embodiment of the present invention;

FIG. 3 is an enlarged schematic view of an adsorptive particle layer according to a first embodiment of the present disclosure;

FIG. 4 is a schematic cross-sectional view of a composite fiber according to a first embodiment of the present invention;

fig. 5 is a schematic longitudinal section of a single active particle according to a first embodiment of the present invention.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

As shown in fig. 2, a cross-sectional view of a filter medium 3, which comprises an adsorptive particle layer 4 and a non-woven fabric support layer 5, the adsorptive particle layer 4 is located between two non-woven fabric support layers 5, so as to prevent the adsorptive particle layer 4 from falling off in the using process. As shown in the enlarged schematic view of the absorbent particle layer of fig. 3 and the schematic view of the longitudinal section of a single active particle of fig. 5, the absorbent particle layer 4 includes active particles 7, fibers 6 and a binder 9. As shown in fig. 4, which is a schematic cross-sectional view of the composite fiber, the binder 9 and the fiber 6 together form the composite fiber 8 having a sheath-core structure, the binder 9 wraps the fiber 6, and when the composite fiber 8 is heated, the binder 9 is thermally melted to generate viscosity, and a bonding region 10 is formed on the surface of the active particles 7. In this way, the active particles 7 and the fibers 6 can be better bonded together, and the bonding force between the active particles 7 and the fibers 6 is increased, so that the reinforcing effect of the fibers 6 in the absorbent particle layer 4 is obvious. The surface of the active particles 7 is formed with a bonding area 10 and an active area 11, the bonding area 10 having adhesive properties to bond the active particles 7 to the fibers 6. In order to ensure the bonding strength between the active particles 7 and the fibers 6 and ensure the adsorption effect of the active particles 7, the area ratio of the bonding region 10 to the active region 11 is in the range of 1:200 to 1: 50. If the area ratio of the bonding region 10 to the active region 11 is less than 1:200, the bonding region 10 has an excessively small area ratio to the active particles 7, and thus has a poor bonding effect to the fibers 6, and when the filter medium 3 is subjected to a force, the active particles 7 and the fibers 6 are easily separated from each other, so that the fibers 6 and the active particles 7 are easily separated from the filter medium 3. The area ratio of the bonding area 10 to the active area 11 is more than 1:50, and the area of the active area 11 with the adsorption and filtration functions is too small, so that the adsorption quantity and the filtration efficiency of the filter medium 3 are influenced; when the area ratio of the bonding region 10 to the active region 11 is within the range of 1: 200-1: 50, the active particles 7 and the fibers 6 are bonded together, on one hand, the fibers 6 can support the adsorptive particle layer 4, on the other hand, the fibers 6 can play a role in enhancing and toughening in the adsorptive particle layer 4, stress acting on the active particles 7 can be transmitted to the active particles 7 through the fibers 6 in a dispersed manner, and the strength and toughness of the adsorptive particle layer 4 are greatly improved while the adsorption and filtration performance of the active particles 7 are ensured. For convenience of expression, the active particles 7 in both fig. 2 and 3 are simplified to be circular.

In order to ensure that the active particles 7 are firmly bonded to the fibers 6 and to prevent the active particles 7 from falling off when the filter medium 3 is subjected to a force, the bonding region 10 on the surface of the active particles 7 comprises at least three bonding points 12. In this way, the fibers bonded to the surface of the active particles 7 can form at least a stable triangle, and the active particles 7 are sandwiched between the fibers 6 to form a stable and firm structure.

The diameter z of the fibers 6 and the diameter x of the active particles 7 are such that: x/z is more than or equal to 20 and less than or equal to 70, and at the moment, the contact surface of the fiber 6 and the active particles 7 is a point, so that the bonding fastness of the active particles 7 on the fiber 6 can be maintained, and the influence of the fiber 6 on the adsorbability of the active particles 7 can be avoided.

In the present invention, after the layer of adsorptive particles 4 is formed by bonding the active particles 7 to the fibers 6, the layer of adsorptive particles 4 is then bonded to the nonwoven support layer 5 by the bonding regions 10 to form the filter media 3. By the design, the adsorptive particle layer 4 has a bonding effect, and the production and manufacturing process steps of the filter medium are simplified.

Further, when the composite fiber 8 is heated to form a bonding effect, in order to avoid the influence of temperature on the structure and performance of the fiber 6 and further influence the reinforcing effect of the fiber 6 in the absorbent particle layer 4, the melting point of the binder 9 is at least 20 ℃ lower than the melting point of the fiber 6. In order to better bond the active particles 7 and the fibers 6 together, increase the bonding effect of the active particles 7 and ensure the bonding effect among the active particles 7, the fibers 6 and the non-woven fabric support layer 5, the filter medium 3 also comprises rubber powder, and when the filter medium 3 is heated, the rubber powder is melted by heat to form first bonding areas 14 on the surfaces of the active particles 7. It is noted that the bonding region 10 on the active particle of fig. 5 has an exaggerated composition in order to distinguish the bonding region 10 from the first bonding region 14. It is often the case that the bond region 10 and the first bond region 14 are not completely separated, and it is possible that the first bond region 14 becomes incorporated into the bond region 10.

The material of the binder 9 is selected from one of polyethylene and polypropylene, and the material of the fiber 6 is selected from one of polyethylene terephthalate, polytrimethylene terephthalate and polybutylene terephthalate. The raw materials are low in price and easy to machine and form. More importantly, the binder 9 has good compatibility with the fibers 6, and the two are not peeled off from each other after being processed into the composite fibers 8. And the fiber comprises long fiber and short fiber, the length x of the long fiber satisfies: x is more than or equal to 30mm, and the length y of the short fiber satisfies the following conditions: y is less than or equal to 25 mm. Therefore, the dimension mixing degree of the fiber can be increased, and the problem that the effect of the fiber with a single dimension is poor in the aspect of improving the comprehensive performance is solved.

A method for preparing a filter medium comprises the following steps:

wherein the volume ratio of the skin layer to the core layer of the composite fiber is 1: 14;

Hot-pressing by a hot roller at the temperature of DEG C;

s5: cooling to obtain the comparative example 1.

According to the process steps, the volume ratio of the skin layer to the core layer of the composite fiber is changed to obtain different comparative examples and examples, and the specific results are shown in the following table 1:

TABLE 1 Filter media types

Firstly, a first adsorptive particle layer is scattered on a non-woven fabric supporting layer 5, then composite fibers 8 are laid on the first adsorptive particle layer to form a semi-finished product, finally, another non-woven fabric supporting layer 5 is laid on the semi-finished product, and the filtering medium 3 is formed by hot roller processing. The composite fiber 8 is softened after the step of S3 to generate stickiness and form a bonding region 10 on the surface of the active particle 7, and a portion where the bonding region 10 is not formed still has an adsorption property, which is called as an active region 11. As an improvement of the invention, the volume ratio of the skin layer to the core layer of the composite fiber 8 with the skin-core structure is within the range of 1: 10-10: 1. By selecting the above method, the skin layer of the composite fiber 8 can be heated to form the bonding region 10 on the surface of the active particle 7, and at the moment, the area ratio of the bonding region 10 on the surface of the active particle 7 to the active region 11 can be ensured to be within the range of 1: 200-1: 50.

To verify the effect of the volume ratio of the sheath and core layers of the composite fiber 8 on the area ratio of the active region 11 to the bonded region 10 on the surface of the active particle 7, and the effect of the area ratio of the bonded region 10 to the active region 11 on the performance of the filter media (including filtration performance and active particle bond strength), the following experiments were designed:

first, filtration performance of the filter medium

The filtration efficiency and filtration resistance of the filter media were tested using an AMC tester according to the ASHRAE 145.1 standard. The test flow is 29.3L/min, and the test area is 26.4cm². The test data are shown in Table 2:

secondly, the adhesion effect of the active particles on the filter medium:

1. a (25X25) cm sample of filter media was prepared.

2. Measuring the vertical height of 1m by using a standard vertical measuring ruler, marking, and placing a container capable of containing a sample right below the mark.

3. The sample was dropped into the container by a free fall movement from a height of 1 m.

4. The active particles scattered in the container were collected and weighed in grams.

4. The above procedure was repeated 3 times and the average number of grams of active particles scattered, expressed as g, was calculated. The test data are shown in Table 2:

TABLE 2 test data

As can be seen from table 2 above, when the skin layer content of the composite fiber is higher, the bonding area on the surface of the active particle is also larger, and the active particle has a good bonding effect, and can bond the active particle and the fiber together well, so as to be fixed in the filter medium. When the ratio of the skin layer to the core layer of the composite fiber is less than 1:10, and the area ratio of the bonding area on the surface of the active particle to the active area is less than 1:200, at this time, the area of the bonding area on the surface of the active particle is too small, and the active particle is easy to fall off from the filter medium, namely the data of comparative example 1 shows; and when the ratio of the skin layer to the core layer of the composite fiber is more than 10:1, the area ratio of the bonding region of the active particle surface to the active region is greater than 1:50, and at this time, the area of the active region having the filtering performance on the active particle surface is reduced due to the excessively large area of the bonding region, and the filtering efficiency of the filter medium is reduced while the filtering resistance is increased, as shown in the data of comparative example 2. When the volume ratio of the skin layer to the core layer of the composite fiber is within the range of 1: 10-10: 1, the area ratio of the bonding area on the surface of the active particle to the active area is within the range of 1: 200-1: 50, and at the moment, the filtering effect of the filter medium and the bonding effect of the active particle 7 reach a balance, namely, the data of the examples 1-3 show.

In order to further enhance the bonding effect between the adsorptive particle layer 4 and the nonwoven fabric support layer 5 and prevent the adsorptive particle layer 4 from falling off from the filter medium 3, the first adsorptive particle layer and the second adsorptive particle layer contain rubber powder.

The step S1 includes preheating at 100-150 deg.C for 1-10 min. So, in follow-up preheating step, can guarantee that the product is even to be heated, guarantee because of the heating effect and produce the formation of the bonding area of bonding effect on the active particle surface, and then guarantee bonding strength between adsorptivity grained layer and the non-woven fabrics supporting layer.

The step of S2 may be repeated multiple times. So, can be when guaranteeing filter medium bonding strength, increase the thickness of the adsorptivity grained layer in the filter medium, increase filter medium's adsorption filtration effect. And there is a Sa step between the steps S2 and S3,

sa: and melt-blowing the glue blocks into glue threads onto the fiber felt through a hot melt glue machine, wherein the diameter of the glue threads is 10-50 mu m, the glue blocks are selected from one or more of polyolefin, EVA and polyurethane, and the heating temperature of the S3 step is 100-160 ℃. In this way, the bonding strength of the filter medium is provided by the viscosity of the fiber felt and the glue thread, and the bonding effect of the filter medium is increased.

While the preferred embodiments of the present invention have been illustrated and described in detail, it should be understood that various changes and modifications of the invention can be effected therein by those skilled in the art after reading the above teachings of the invention. Such equivalents are intended to fall within the scope of the claims appended hereto.

Claims

1. A filter media comprising an adsorptive particle layer and a non-woven support layer, the adsorptive particle layer comprising fibers and active particles, characterized in that: the composite fiber of the skin-core structure is formed by the binder and the fibers, the binder is used as a skin layer of the composite fiber, the fibers are used as a core layer of the composite fiber, a bonding region is formed on the surface of the active particle by the binder, the surface of the active particle further comprises an active region, and the area ratio of the bonding region to the active region is within the range of 1: 200-1: 50.

2. The filter media of claim 1, wherein the bond region comprises at least three bonds.

3. The filter medium according to claim 2, wherein the diameter z of the fibers and the diameter x of the active particles satisfy: x/z is more than or equal to 20 and less than or equal to 70.

4. The filter media of claim 1, wherein the bonding region bonds the layer of adsorbent particles to the nonwoven support layer.

5. The filter media of claim 1, further comprising a glue powder, the bond regions comprising first bond regions, the glue powder being thermally fused to form the first bond regions.

6. The filter media of claim 1, wherein the binder has a melting point at least 20 ℃ lower than the melting point of the fibers.

7. The filter medium of claim 6, wherein the binder material is selected from one of polyethylene and polypropylene, and the fiber material is selected from one of polyethylene terephthalate, polypropylene terephthalate and polybutylene terephthalate.

8. The filter media of claim 1, wherein the fibers comprise long fibers and short fibers, the long fibers having a length x that satisfies: x is more than or equal to 30mm, and the length y of the short fiber satisfies the following conditions: y is less than or equal to 25 mm.

9. A method of making a filter media, comprising the steps of:

s2: laying the composite fiber with the skin-core structure on the surface of the first adsorptive particle layer, and scattering a second adsorptive particle layer on the surface of the composite fiber to form a semi-finished product;

s4: laying a non-woven fabric supporting layer on the second adsorptive particle layer, and performing hot-pressing processing through a hot roller at the temperature of 150-240 ℃;

s5: cooling to obtain the filter medium.

10. The method of claim 9, wherein the step of S2 is repeated a plurality of times.

11. The method of claim 9, wherein the first layer of adsorbent particles and/or the second layer of adsorbent particles comprises a gum powder.

12. The method as set forth in claim 9, wherein the step of S1 includes preheating to 100-150 ℃ for 1-10 min.

13. The method of claim 9, wherein a Sa step is provided between the steps S2 and S3,