CN113622088B

CN113622088B - Fluffy coarse fiber melt-blown cloth, preparation method and fluffy coarse fiber melt-blown cloth filter element

Info

Publication number: CN113622088B
Application number: CN202110595873.1A
Authority: CN
Inventors: 徐建明; 郑海明; 张虞旭驹; 贾建东
Original assignee: Hangzhou Kebaite Technology Co ltd
Current assignee: Hangzhou Kebaite Technology Co ltd
Priority date: 2021-09-03
Filing date: 2021-09-03
Publication date: 2023-05-02
Anticipated expiration: 2041-09-03
Also published as: CN113622088A

Abstract

The invention relates to a fluffy coarse fiber melt-blown cloth, which comprises fiber filaments stacked and bonded with each other, wherein the thickness of the fluffy coarse fiber melt-blown cloth is between 400 and 900 mu m, 16 fluffy coarse fiber melt-blown cloths are stacked, and a force of 757Pa is applied to the surface of the fluffy coarse fiber melt-blown cloth, and the thickness of the fluffy coarse fiber melt-blown cloth is reduced by 30 to 80 percent relative to the original thickness. The ratio of the diameter of the coarse fiber filaments to the thickness of the meltblown web is set between 1/60 and 1/10. The diameter of the coarse fiber filaments is greater than 15 μm. The filaments also include filaments having a diameter of less than 10 μm. The fiber filaments are uniform in evenness, and the diameter of the thickest part of each single fiber filament is not more than 150% of the diameter of the thinnest part of each single fiber filament. The invention aims to provide fluffy coarse fiber melt-blown cloth with certain fluffiness, better compression resistance and dirt holding property and longer service life.

Description

Fluffy coarse fiber melt-blown cloth, preparation method and fluffy coarse fiber melt-blown cloth filter element

Technical Field

The invention relates to melt-blown cloth and a preparation method thereof and a melt-blown cloth filter element, in particular to fluffy coarse fiber melt-blown cloth and a preparation method thereof and a fluffy coarse fiber melt-blown cloth filter element.

Background

The melt-blown fabric is a fabric prepared by a non-woven process, and generally takes polymer as a main material, and structurally, the melt-blown fabric has a plurality of gaps, fluffy structure and good crease resistance, and the fibers with unique capillary structures increase the number and the surface area of the fibers per unit area, so that the melt-blown fabric has good filterability, shielding property, heat insulation property and oil absorption property. Can be used in the fields of air, liquid filtering materials, isolating materials, absorbing materials, mask materials, thermal insulation materials, oil absorption materials, wiping cloth and the like.

A typical meltblown cartridge generally includes a central rod and a meltblown web wound about the outside of the central rod. When the filter element is in filtration, no matter the filter element is in the filtration direction of the outside in and the inside out or the inside in and out, filtrate passes through from one surface of the melt-blown cloth to the other surface of the melt-blown cloth, namely, the filtrate flows in the thickness direction of the melt-blown cloth, and certain pressure is generated on the surface of the melt-blown cloth when the filtrate is in filtration, so that the melt-blown cloth is pressed more tightly, the thickness of the melt-blown cloth is reduced, the whole pollution-receiving amount is reduced under the condition of the rest condition, and the service life is shortened. And when subjected to pressure, the meltblown surface structure undergoes some change, particularly in the shape of the holes, pore size, etc. To a certain extent, the filtering effect is also affected.

Disclosure of Invention

The invention aims to provide fluffy coarse fiber melt-blown cloth with certain fluffiness, better compression resistance and dirt holding property and longer service life.

In order to achieve the above purpose, the invention adopts the following technical scheme: a lofty fibrous meltblown web comprising filaments bonded to one another in a stack, the lofty fibrous meltblown web having a thickness of between 400 μm and 900 μm, the 16 lofty fibrous meltblown webs being stacked and having a force applied to their surfaces in the range of 757Pa, the thickness being reduced by between 30% and 80% relative to the original thickness.

By adopting the technical scheme, the thickness range of the single-layer coarse fiber melt-blown cloth is limited, and the compression amount range in the thickness direction of the coarse fiber melt-blown cloth is also limited to be used as a parameter index for representing the fluffiness degree of the coarse fiber melt-blown cloth under certain conditions. When the lithium battery slurry is used for filtering, the solid content in the slurry is higher, the impurity particles are larger, soft colloid impurities are contained, under a certain filtering pressure, the impurities pass through the melt-blown cloth from the thickness direction of the laminated melt-blown cloth, and when the colloid impurities deform, the melt-blown cloth is extruded so that the surface structure of the melt-blown cloth is bent, twisted and deformed, and the filtering holes are stretched or extruded to change the pore diameter, so that the filtering precision is influenced. If the surface of the coarse fiber melt-blown cloth is too fluffy, namely the thickness reduction is more than 80%, the structural strength of the coarse fiber melt-blown cloth is very low, and the coarse fiber melt-blown cloth is easier to compress and compact when being compressed, so that the filtering holes on the surface of the melt-blown cloth are finer, some substances which do not need to be filtered are blocked outside, meanwhile, the internal space of the compacted melt-blown cloth is very small, enough dirt receiving space cannot be provided, more impurities cannot be contained, the air permeability of the coarse fiber melt-blown cloth is influenced, and the flow speed, the pressure drop and the like during filtering are influenced; if the surface of the coarse fiber melt-blown cloth is too compact, that is, the thickness reduction is less than 30%, this means that the fiber strength of the surface of the coarse fiber melt-blown cloth is too high, and the coarse fiber melt-blown cloth does not have good toughness, and is easily broken under the action of high pressure, so that new impurities are introduced into the filtrate, and even the pressure formed during winding of the fluffy coarse fiber melt-blown cloth may be broken. It should be noted that the definition herein of a thickness of 400 μm to 900 μm means that the thickness at the thickest location on the bulk-fiber meltblown web is no more than 900 μm and that the thickness at the thinnest location is no less than 400 μm, i.e., optionally a bulk-fiber meltblown web, the thickness at any location above satisfies this range.

Further, the filaments include coarse filaments having a ratio of diameter to thickness of the meltblown web of between 1/60 and 1/10.

By adopting the technical scheme, the relative relation between the fiber diameter and the thickness of the melt-blown cloth is limited, if the thickness ratio is too large, the fiber is too thick or the melt-blown cloth is too thin, the filtration precision is reduced due to the too thick fiber, and the strength is reduced due to the too thin melt-blown cloth; if the thickness ratio is too small, it means that the filaments are too thin or the meltblown cloth is too thick, the too thin filaments increase the resistance at the time of filtration, decrease the flow rate, and at the same time the strength is not high, and too thick meltblown cloth causes the pressure drop at the time of filtration to become large, so that an appropriate range needs to be selected. From another angle, the relationship between the fiber diameter and the thickness of the melt-blown fabric can reflect to a certain extent that the thickness of the melt-blown fabric is formed by stacking a plurality of layers of fiber filaments, the stacked layers also structurally affect the fluffiness of the coarse fiber melt-blown fabric, and if the layers are too small, an interlaced supporting structure cannot be formed in the thickness direction, so that the fluffiness effect is realized; if the number of layers is too large, the fiber is distributed more in the thickness direction, the degree of fluffiness is reduced due to the dead weight of the fiber, and the air permeability of the meltblown fabric is affected by too much thickness.

Further, the diameter of the coarse fiber filaments is greater than 15 μm.

Further, the filaments also include filaments having a diameter of less than 10 μm.

Further, the fiber filaments have uniform evenness, and the diameter of the thickest part of each single fiber filament is not more than 150% of the diameter of the thinnest part of each single fiber filament.

Further, the content of the coarse fiber filaments is more than the content of the fine fiber filaments.

By adopting the technical scheme, the diameter of the coarse fibers, the specific diameter and the relative content of the fine fibers are limited, the thickness of the same fiber yarn is uniform, and the melt-blown non-woven fabric prepared by the fiber yarn in the scheme is ensured to be uniform and stable in performance. Meanwhile, the coarse and fine mixing mode can improve the fluffiness of fluffy coarse fiber melt-blown cloth to a certain extent, and the coarse fibers can provide a good supporting effect to form a large dirt receiving space; the fine fibers can improve the filtration accuracy of the meltblown web.

Further, the breaking strength of the fluffy coarse fiber melt-blown cloth is between 5N and 40N.

Through adopting above-mentioned technical scheme, limited the intensity of melt-blown non-woven fabrics, guaranteed its intensity within a certain range, can both guarantee the high strength of non-woven fabrics under the operating mode of different pressures, can not fracture.

Further, the grammage of the fluffy coarse fiber melt-blown cloth is set at 30g/m ² -60g/m ² Between them.

Further, the air permeability of the fluffy coarse fiber melt-blown cloth is set between 3000mm/s and 9000 mm/s.

Through adopting above-mentioned technical scheme, having made the restriction to the gram weight and the air permeability of melt-blown cloth, guaranteed that melt-blown cloth when coiling into the filter core use, let the filtrate have certain velocity of flow, guaranteed the filter effect again.

The invention also provides a method for fluffy coarse fiber melt-blown cloth, which comprises the following steps of S1: mixing raw materials, namely blending one or more polymers with at least two melt indexes, wherein the content of a high melt index part in the raw materials is 65-96.5 wt% and the content of a low melt index part in the raw materials is 3.5-35 wt%; s2: melt spinning, namely melt extruding the blend obtained in the step S1 in an extruder, measuring by a metering pump and drawing by an air knife, and melt-blowing through a spinneret orifice on a spinneret plate to form fiber filaments; s3: and (3) receiving and forming, namely spraying the fiber yarn formed in the step (S2) on a winding net curtain for bonding and forming, wherein the moisture content of air in a space between the spinning holes and the winding net curtain is set between 5g/kg (dry air) and 90g/kg (dry air), and the temperature in the space is set between 60 ℃ and 140 ℃.

By adopting the technical scheme, the range of high and low melt indexes in the raw materials is limited, the formation of coarse fiber filaments and fine fiber filaments is ensured, and the diameter of the fiber filaments is further controlled by controlling the moisture content of the fiber filaments in a space during forming, so that a fluffy melt-blown cloth structure is formed. In the process of spraying the fiber yarn out of the spinneret holes to the winding net curtain, the moisture content and the temperature in the environment can be controlled to influence the final forming form of the fiber yarn under the condition of certain other conditions. The higher the moisture content in the space during forming, the lower the ambient temperature, the faster the fiber yarn cools, the less the fiber yarn is formed as it is drawn and thinned, which has a beneficial effect on forming thicker diameter fiber yarns, and the thicker diameter fiber yarns are stacked and bonded to form a larger space volume, thus having a more excellent degree of fluffiness after winding fluffy coarse fiber melt-blown cloth into a filter element.

Further, the filaments in step S3 are subjected to a transverse force before being bonded and formed on the rolled mesh curtain.

Through adopting above-mentioned technical scheme, the cellosilk receives transverse force before the shaping, can change its motion track in the sky to a certain extent, and the cellosilk takes place in the sky and fuses, twines, gathers together the condition, further increases the diameter of cellosilk to further promote the fluffy degree of crude fiber melt-blown cloth. The transverse force can be generated by a common blowing device, or can be provided by spraying media such as spraying, and the transverse force can be provided while the humidity is provided for the environment.

Further, the transverse force is provided by a spraying device, the spraying pressure of the spraying device is set between 0.05 and 0.8MPa, and the spraying angle is set between 30 and 90 degrees.

Through adopting above-mentioned technical scheme, through atomizer provided the transverse force that the cellosilk received in the sky to limited atomizer's spraying pressure and spraying angle, can let the cellosilk possess best doubling, winding, gathering the effect in the sky, form thick cellosilk, realize the control to melt-blown cloth fluffiness. The spray angle here is specifically the angle between the spray hole direction of the spray and the spray direction of the spray holes for spraying the fiber filaments.

Further, the receiving height of the fluffy coarse fiber melt-blown cloth is set between 80mm and 350mm during forming, and the winding speed of the fluffy coarse fiber melt-blown cloth during receiving forming is set between 15m/min and 40 m/min.

By adopting the technical scheme, the receiving height of the melt-blown fabric during forming and the winding speed of the melt-blown fabric during forming are mainly controlled to control the gram weight of the single-layer coarse fiber melt-blown fabric, and the fluffiness degree of the melt-blown fabric, namely the compression amount of the thickness under certain conditions, can be adjusted to a certain extent. The receiving height here refers in particular to the height from the spinneret orifice to the wound screen; the winding speed refers to the winding speed of the winding net curtain when forming the film. If the receiving height is too low, the temperature of the fiber filaments is too high during forming, different fiber filaments are easy to bond into a pasty structure, the ventilation amount of melt-blown cloth is reduced, meanwhile, the fiber filaments are more densely piled, and the formed non-woven fabric is compact and has lower fluffiness; if the receiving height is too high, the distance between the fiber filaments in the air becomes longer after being sprayed out from the spinneret holes, the fiber filaments are more loose and easy to distribute, the fiber temperature during the non-woven fabric forming is too low, the bonding force between the fibers is too low, and although the fluffiness degree of the melt-blown non-woven fabric can be improved to a certain extent, the melt-blown non-woven fabric is easy to break and scatter, so that the service life of the melt-blown non-woven fabric is reduced. By limiting the winding speed during the forming of the melt-blown non-woven fabric, the content of the fiber filaments in a certain area can be ensured, the fiber filaments are not too much or too little, and the fiber filaments in the same area are distributed less and sparsely as the winding speed is higher, so that the strength of the whole melt-blown non-woven fabric is lower; if the winding speed is low, the fiber yarn distribution in the same area region is dense and compact, and the structural strength of the melt-blown nonwoven fabric can be increased, but the air permeability and the flow rate during filtration are affected. Therefore, in the scheme, the height of the coarse fiber melt-blown non-woven fabric during forming and the winding speed during forming are combined, so that the final coarse fiber melt-blown non-woven fabric product is ensured to have better fluffiness degree, and better filtering effect and structural strength are achieved.

Further, the diameter of the spinneret holes on the spinneret plate is set between 0.1mm and 0.5mm, and the length-diameter ratio of the spinneret holes is set between 15 and 30.

Further, the length of the spinneret plate is 1000mm-1400mm, the number of the spinneret holes on the spinneret plate is 2500-3200, and the interval between the spinneret holes is 0.3mm-1 mm.

Through adopting above-mentioned technical scheme, having made the restriction to the relevant parameter of spinneret and spinneret orifice, the diameter of spinneret orifice can control the diameter of cellosilk, and the draw ratio can influence the melt and extrude the puffing phenomenon when the spinneret orifice, influences the shaping of cellosilk, and spinneret length, spinneret orifice quantity and interval are all in order to promote production efficiency as far as possible under the prerequisite that does not influence the cellosilk quality.

Further, air knives are arranged on two sides of the spinneret holes, and the distance between the inclined planes of the air knives and the inclined planes of the spinneret holes is 0.5mm-1.0 mm.

By adopting the technical scheme, the distance range of the inclined plane of the air knife and the inclined plane where the spinneret orifice is positioned is limited, and if the distance is too small, the diameter of the fiber filaments sprayed out of the spinneret orifice is influenced, so that the fiber filaments become uneven under the action of high wind force; if the distance is too large, the effect of the air knife for pulling the silk thread cannot be achieved, so that the silk thread is easy to stack at the silk-spraying hole, silk spraying cannot be smoothly performed, and even the silk-spraying hole is blocked.

Further, the temperature of hot air generated by the air knife is between 180 ℃ and 300 ℃, and the air pressure is between 20kPa and 200 kPa.

Further, the hot air volume of the air knife is set at 10m ³ /min-25m ³ And/min.

By adopting the technical scheme, the hot air quantity of the air knife, the temperature of the air knife and the air pressure are controlled, and if the hot air temperature is too low. The fiber filaments are easy to cool quickly after being sprayed out of the spinneret orifices, so that the bonding of the melt-blown non-woven fabric during forming is affected; if the temperature is too high, the filaments tend to be more molten, have good fluidity, and are not easily maintained in a filament-like structure. If the wind pressure is too low, the traction effect on the fiber yarn is poor; if the wind pressure is too high, the filaments are easily blown off, and fly in the air. If the hot air quantity is too low, a part of fiber filaments can ensure a certain temperature and a certain viscosity, and a part of fiber filaments are still easy to cool and fast, so that the bonding during the forming of the melt-blown non-woven fabric is affected; if the hot air quantity is too high, under the condition that the fiber yarn is not formed, the too high air quantity blows off the fiber yarn to form fly, and the forming of the melt-blown non-woven fabric is affected.

Further, the included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set between 60 degrees and 90 degrees.

By adopting the technical scheme, the included angle formed by the air knives at the two sides of the spinneret hole is limited, if the included angle is too large, the traction effect of hot air on the fiber yarn is smaller, and meanwhile, the transverse acting force on the fiber yarn is larger, so that the diameter of the fiber yarn is easy to influence; if the included angle is too small, the force received in the transverse direction by the filaments is small and tends to diverge outwardly after being ejected from the orifices.

Further, the flow rate of the blend within the spinneret is between 0.05ghm and 0.5 ghm.

By adopting the technical scheme, the high yield of the spinneret orifices can be ensured, and if the flow speed is too slow, the yield is low; if the flow rate is too high for high productivity, the fiber ejected from the spinneret holes is severely bulked and easily plugs the spinneret holes.

Further, the cooling device in the step S3 is a constant-temperature spraying system, the spraying temperature is kept between 15 ℃ and 30 ℃, the spraying flow is set between 80ml/min and 500ml/min, the spraying pressure is set between 0.2MPa and 0.5MPa, and the center-to-center distance between a spinneret orifice of the spraying system and a spinneret plate is set between 20cm and 40 cm.

Through adopting above-mentioned technical scheme, cool down the higher cellosilk of mobility from the spinneret orifice, make cellosilk itself can keep certain filiform form, be in a comparatively stable state through temperature, flow, pressure, the distance that control constant temperature spraying system sprayed can guarantee that whole environment is in, make single cellosilk can have better homogeneity, can not thickness uneven.

Further, an air suction device is arranged on one side, away from the forming side, in the step S3, and the air suction device is simultaneously started in the step S3.

Through adopting above-mentioned technical scheme, the setting of device that induced drafts can firmly adsorb the cellosilk on winding net curtain surface when the cellosilk shaping, can improve the bonding effect between cellosilk and the cellosilk to a certain extent through the adsorption affinity of physics, control the production of flying the flower simultaneously.

The invention also provides a filter element containing the fluffy coarse fiber melt-blown cloth, which comprises a central rod and a medium layer formed by the fluffy coarse fiber melt-blown cloth belt wound outside the central rod, wherein the fluffy coarse fiber melt-blown cloth belt and the supporting net belt are wound at the same time, the fluffy coarse fiber melt-blown cloth belt at least comprises two types of precision, and the fluffy coarse fiber cloth belt with high precision is arranged closer to the central rod.

Through adopting above-mentioned technical scheme, the existence of supporting the guipure can be with carrying out the interval between the crude fiber melt-blown cloth, has provided the space that supports intensity and holds impurity. Meanwhile, the gradient filtering effect can be realized through coarse fiber melt-blown cloth with at least two kinds of precision, and the precision in the filter element is high, so that large-particle impurities are blocked at the outer layer relative to the filter element, and small-particle impurities are blocked at the inner layer relative to the filter element. If the coarse fiber meltblown is of a precise type, during filtration, no matter whether the filter is in the outer inlet or the inner inlet or the outer outlet, a large amount of impurities exist on the liquid inlet side, so that the dirt receiving capacity on the liquid inlet side is saturated quickly, and the coarse fiber meltblown far away from the liquid inlet side is far less saturated, so that the function of the coarse fiber meltblown far away from the liquid inlet side is wasted.

Further, the innermost side of the dielectric layer comprises an inner barrier layer formed by a supporting net belt; the outermost side of the dielectric layer comprises an outer barrier layer formed by a supporting net belt.

By adopting the technical scheme, as the surface of the central rod is provided with the through holes for facilitating the flow of liquid, when the filtering mode is an external-in and internal-out mode, if no internal barrier layer exists, the coarse fiber melt-blown cloth is easily pressed into the central rod due to the filtering pressure; the arrangement of the outer barrier layer can ensure that the outer surface of the filter element is provided with a protective layer, and can prevent coarse fiber melt-blown cloth from being scattered by pressure under the condition that the filtering mode is the inner inlet and the outer outlet.

Further, the fluffy coarse fiber melt-blown cloth belt is single; or a plurality of fluffy coarse fiber melt-blown cloth belts are arranged, and the end surfaces of the adjacent fluffy coarse fiber melt-blown cloth belts are connected with each other in a projection manner on the supporting mesh belt; or the number of the fluffy coarse fiber melt-blown cloth belts is multiple, and the projection of the end surfaces of the adjacent fluffy coarse fiber melt-blown cloth belts on the supporting net belt is distributed at intervals.

By adopting the technical scheme, the relative relation between the fluffy coarse fiber melt-blown cloth belt and the supporting net belt is limited, and convenience and continuity in the filter element production process are ensured. The fluffy coarse fiber melt-blown cloth belt can fully utilize the space inside the fluffy coarse fiber melt-blown cloth belt after being wound, and waste is avoided.

Further, when the fluffy coarse fiber melt-blown cloth belts are multiple, the adjacent fluffy coarse fiber melt-blown cloth belts are respectively positioned at two sides of the supporting net belt.

By adopting the technical scheme, the high efficiency of production can be ensured in continuous mechanical production conveniently.

Further, three fluffy coarse fiber melt-blown cloth belts are arranged, the thickness of the first fluffy coarse fiber melt-blown cloth belt is 600-750 mu m, and the ventilation quantity is 3000-5000 mm/s; the thickness of the second fluffy coarse fiber melt-blown cloth belt is 600-850 mu m, and the ventilation quantity is 5000-7000 mm/s; the thickness of the third fluffy coarse fiber melt-blown cloth belt is 550-800 mu m, and the ventilation quantity is 6000-9000 mm/s.

Through adopting above-mentioned technical scheme, limited the thickness and the ventilative volume of different fluffy crude fiber melt-blown strap, provided the fluffy crude fiber melt-blown strap of three kinds of different precision, different thickness cooperation ventilative volume cooperates different precision again, can let the filter effect of filter core realize optimizing.

Furthermore, the filtering precision of the fluffy coarse fiber melt-blown filter element is less than or equal to 300um, and the interception efficiency for different filtering precision is more than or equal to 95 percent.

By adopting the technical scheme, the filter element has the advantages that the filter element is limited in terms of filtering performance, and the filter element product is ensured to have excellent filtering performance.

Further, the thickness of the supporting mesh belt is between 600 and 750 mu m, the supporting mesh belt is uniformly provided with grids, and the weaving angle of the grids is between 85 and 95 degrees.

By adopting the technical scheme, the parameters of the supporting net are defined in a correlated way, so that the supporting net is ensured to have certain structural strength and a pollution receiving space.

Compared with the prior art, the fluffy coarse fiber melt-blown fabric has the advantages that: 1. the bulk coarse fiber meltblown web has a degree of bulk in the thickness direction but is not so tightly compressed when subjected to pressure that it does not provide a space for receiving the soil. 2. The fiber yarn diameter of the melt-blown cloth is larger, so that the melt-blown cloth has higher structural strength and can adapt to the use condition of larger pressure. 3. The relative proportion relation between the thickness of the fluffy coarse fiber melt-blown cloth and the thickness of the fiber filaments on the surface of the fluffy coarse fiber melt-blown cloth is ensured, so that the fluffy coarse fiber melt-blown cloth has structural strength and simultaneously ensures the filtering precision of the fluffy coarse fiber melt-blown cloth.

Compared with the prior art, the preparation method of the fluffy coarse fiber melt-blown fabric has the advantages that: 1. a lofty coarse fiber meltblown web can be prepared that contains both coarse and fine fiber filaments. 2. Meltblown webs can be produced that have a degree of loft. 3. The preparation method is relatively simple and controllable, and is beneficial to continuous mechanical production.

Compared with the prior art, the fluffy coarse fiber non-woven fabric filter element has the advantages that: 1. when bearing higher pressure, can also guarantee that the outside filter medium of filter core has certain and receive dirty space, make filter medium can not flattened. 2. The filter element has a certain filtering gradient, so that the filter element space can be fully utilized to achieve the optimal filtering effect.

Drawings

The invention is further described below with reference to the accompanying drawings:

fig. 1 is a schematic structural diagram of an eleventh embodiment of the present invention.

In the figure: 1. a central rod; 2. supporting the mesh belt; 2a, a first melt-blown cloth belt; 2b, a second melt-blown cloth belt; and 2c, third melt-blown cloth belt.

Detailed Description

In order that the above-recited objects, features and advantages of the invention will be more clearly understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof. It should be noted that, in the case of no conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

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 described herein, and therefore the scope of the present invention is not limited to the specific embodiments disclosed below.

Embodiment one:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials were mixed, and polypropylene having a melt index of 1400g/10min and polypropylene having a melt index of 31g/10min were mixed, wherein the polypropylene content of the high melt index was 96.5wt% and the polypropylene content of the low melt index was 3.5wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 80mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 15m/min when the fluffy coarse fiber melt-blown cloth is formed.Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set to 5g/kg (dry air), and the temperature in this region was set to 60 ℃. Further, in the space region, the fiber yarn was sprayed using a spraying device, the spraying pressure was set to 0.05MPa, the spraying angle was set to 30 °, the spraying temperature was 15 ℃, the spraying flow rate was 80ml/min, and the center-to-center distance between the nozzle of the spraying system and the spinneret plate was set to 20cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.1mm, the aspect ratio of the spinneret orifices was set to 15, the length of the spinneret plate was 1000mm, the number of the spinneret orifices was set to 2500, the spacing between the spinneret orifices was set to 0.3mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.05ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane of the spinneret hole is 0.5mm, the temperature of hot air generated by the air knives is 180 ℃, the wind pressure is 20kPa, and the air quantity of the hot air is 10m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 60 degrees. And when the fiber yarn spray paper is formed in the step S3, an air suction device (such as an exhaust fan and the like) is further arranged on one side of the winding net curtain, which is away from the forming side, and the air suction device is started while the melt-blown fabric is formed so as to prevent the formation of flying.

The fluffy coarse fiber melt-blown cloth prepared by the above scheme has a thickness of 402 μm, 16 fluffy coarse fiber melt-blown cloths are stacked, a force of 757Pa is applied to the surface of the fluffy coarse fiber melt-blown cloth, and after compression, the thickness reduction amount of the fluffy coarse fiber melt-blown cloth is 31%. The diameter of the coarse fiber yarn is 16 mu m, the diameter of the fine fiber yarn is 9 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwovenThe fabric making test method, part 3, determination of breaking strength and elongation at break (bar sample method) to measure breaking strength of 6N for meltblown fabrics. Further measurable grammage of the fluffy coarse fiber meltblown cloth is 31g/m ² The ventilation is 3034mm/s.

Embodiment two:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials were mixed, and a polypropylene having a melt index of 1100g/10min and a polypropylene having a melt index of 26g/10min were mixed, wherein the polypropylene content of the high melt index was 90.4wt% and the polypropylene content of the low melt index was 9.6wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 100mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 20m/min when the fluffy coarse fiber melt-blown cloth is formed. Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set to 25g/kg (dry air), and the temperature in this region was set to 70 ℃. Further, in the space region, the fiber yarn was sprayed using a spraying device, the spraying pressure was set to 0.2MPa, the spraying angle was set to 50 °, the spraying temperature was 20 ℃, the spraying flow rate was 120ml/min, and the center-to-center distance between the nozzle of the spraying system and the spinneret plate was set to 25cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.2mm, the aspect ratio of the spinneret orifices was set to 18, the length of the spinneret plate was 1100mm, the number of the spinneret orifices was set to 2600, the spacing between the spinneret orifices was set to 0.4mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.1ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane of the spinneret hole is 0.6mm, the temperature of hot air generated by the air knives is 200 ℃, the wind pressure is 40kPa, and the air quantity of the hot air is 15m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 70 degrees. In the step S3, when the fiber yarn spray paper is formed on the winding curtain, the side of the winding curtain, which is away from the forming, is also provided withAnd the air suction device (such as an exhaust fan and the like) is started while the melt-blown fabric is formed so as to prevent the formation of fly.

The fluffy coarse fiber melt-blown cloth prepared by the above scheme has a thickness of 463 μm, 16 fluffy coarse fiber melt-blown cloths are stacked, a force of 757Pa is applied to the surface of the fluffy coarse fiber melt-blown cloth, and after compression, the thickness reduction amount of the fluffy coarse fiber melt-blown cloth is 37%. The diameter of the coarse fiber yarn is 19 mu m, the diameter of the fine fiber yarn is 8 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure breaking strength of 10N for meltblown. Further measurable grammage of the fluffy coarse fiber meltblown fabric was 38g/m ² The ventilation is 4360mm/s.

Embodiment III:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials are mixed, and polypropylene with the melt index of 1000g/10min and polypropylene with the melt index of 20g/10min are mixed, wherein the content of the polypropylene with the high melt index is 85.1wt% and the content of the polypropylene with the low melt index is 14.9wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 140mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 25m/min when the fluffy coarse fiber melt-blown cloth is formed. Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set to 35g/kg (dry air), and the temperature in this region was set to 80 ℃. Further, in the space region, the spray device is used for aligning the fibersThe vitamin wires are sprayed, the spraying pressure is set to be 0.3MPa, the spraying angle is set to be 60 degrees, the spraying temperature is 25 ℃, the spraying flow is 160ml/min, and the center-to-center distance between a spray hole of a spraying system and a spinneret plate is set to be 30cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.3mm, the aspect ratio of the spinneret orifices was set to 21, the length of the spinneret plate was 1200mm, the number of the spinneret orifices was set to 2700, the spacing between the spinneret orifices was set to 0.5mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.2ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane of the spinneret hole is 0.7mm, the temperature of hot air generated by the air knives is 240 ℃, the wind pressure is 80kPa, and the air quantity of the hot air is 20m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 80 degrees. And when the fiber yarn spray paper is formed in the step S3, an air suction device (such as an exhaust fan and the like) is further arranged on one side of the winding net curtain, which is away from the forming side, and the air suction device is started while the melt-blown fabric is formed so as to prevent the formation of flying.

The fluffy coarse fiber meltblown cloth prepared by the above scheme has a thickness of 511 μm, 16 fluffy coarse fiber meltblown cloths are stacked, and a force of 757Pa is applied to the surface of the fluffy coarse fiber meltblown cloth, and after compression, the thickness reduction amount of the fluffy coarse fiber meltblown cloth is 46%. The diameter of the coarse fiber yarn is 23 mu m, the diameter of the fine fiber yarn is 7 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure breaking strength of 15N for meltblown. Further measurable grammage of the fluffy coarse fiber meltblown fabric was 44g/m ² The ventilation is 5028mm/s.

Embodiment four:

awningThe preparation method of the loose fiber melt-blown cloth comprises the following steps of S1: the raw materials were mixed, and polypropylene having a melt index of 1200g/10min and polypropylene having a melt index of 23g/10min were mixed, wherein the polypropylene content of the high melt index was 79wt% and the polypropylene content of the low melt index was 21wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 190mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 30m/min when the fluffy coarse fiber melt-blown cloth is formed. Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set to 45g/kg (dry air), and the temperature in the region was set to 90 ℃. Further, in the space region, the fiber yarn was sprayed using a spraying device, the spraying pressure was set to 0.4MPa, the spraying angle was set to 70 °, the spraying temperature was 30 ℃, the spraying flow rate was 200ml/min, and the center-to-center distance between the nozzle of the spraying system and the spinneret plate was set to 35cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.4mm, the aspect ratio of the spinneret orifices was set to 25, the length of the spinneret plate was 1300mm, the number of the spinneret orifices was set to 2800, the interval between the spinneret orifices was set to 0.6mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.3ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane of the spinneret hole is 0.8mm, the temperature of hot air generated by the air knives is 260 ℃, the wind pressure is 120kPa, and the air quantity of the hot air is 25m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 90 degrees. And when the fiber yarn spray paper is formed in the step S3, an air suction device (such as an exhaust fan and the like) is further arranged on one side of the winding net curtain, which is away from the forming side, and the air suction device is started while the melt-blown fabric is formed so as to prevent the formation of flying.

The fluffy coarse fiber melt-blown cloth prepared by the scheme has the thickness of 627 mu m, 16 fluffy coarse fiber melt-blown cloths are stacked, and a force with the size of 757Pa is applied to the surface of the fluffy coarse fiber melt-blown cloth, and after the fluffy coarse fiber melt-blown cloth is compressed, the fluffy coarse fiber melt-blown cloth is formedThe thickness reduction was 53%. The diameter of the coarse fiber yarn is 28 mu m, the diameter of the fine fiber yarn is 5 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure a breaking strength of 26N for meltblown. Further measurable grammage of the fluffy coarse fiber meltblown fabric was 51g/m ² The ventilation is 6492mm/s.

Fifth embodiment:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials were mixed, and polypropylene having a melt index of 1400g/10min and polypropylene having a melt index of 22g/10min were mixed, wherein the polypropylene content of the high melt index was 72.5wt% and the polypropylene content of the low melt index was 27.5wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 230mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 35m/min when the fluffy coarse fiber melt-blown cloth is formed. Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set to 55g/kg (dry air), and the temperature in the region was set to 100 ℃. Further, in the space region, the fiber yarn was sprayed using a spraying device, the spraying pressure was set to 0.6MPa, the spraying angle was set to 80 °, the spraying temperature was 25 ℃, the spraying flow rate was 250ml/min, and the center-to-center distance between the nozzle of the spraying system and the spinneret plate was set to 40cm. In this example, the diameter of the spinneret holes on the spinneret plate was set to 0.5mm, the aspect ratio of the spinneret holes was set to 27, and the length of the spinneret plate was set to 1400mm the number of orifices was set to 2900, the spacing between orifices was set to 0.7mm and the flow rate of the blend in the molten state of the feedstock in the spinneret was 0.4ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane where the spinneret hole is positioned is set to be 0.9mm, the temperature of hot air generated by the air knives is set to be 280 ℃, the wind pressure is set to be 150kPa, and the wind quantity of the hot air is 22m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 85 degrees. And when the fiber yarn spray paper is formed in the step S3, an air suction device (such as an exhaust fan and the like) is further arranged on one side of the winding net curtain, which is away from the forming side, and the air suction device is started while the melt-blown fabric is formed so as to prevent the formation of flying.

The fluffy coarse fiber meltblown cloth prepared by the above scheme has a thickness of 721 μm, 16 fluffy coarse fiber meltblown cloths are stacked, and a force of 757Pa is applied to the surface thereof, and after compression, the thickness reduction amount thereof is 61%. The diameter of the thick fiber yarn is 32 mu m, the diameter of the thin fiber yarn is 4 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the thick fiber yarn is more than that of the thin fiber yarn as can be seen from an electron microscope image of fluffy thick fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure a breaking strength of 33N for meltblown. Further measurable grammage of the fluffy coarse fiber meltblown cloth was 55g/m ² The ventilation is 7301mm/s.

Example six:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials were mixed, and polypropylene having a melt index of 1700g/10min and polypropylene having a melt index of 25g/10min were mixed, wherein the polypropylene content of the high melt index was 65.7wt% and the polypropylene content of the low melt index was 34.3wt%. Step S2: extruding the blend obtained in the step S1After melt extrusion in the machine, metering by a metering pump and drawing by an air knife, melt-blowing by a spinneret plate, setting the receiving height to 270mm when the fluffy coarse fiber melt-blowing cloth is formed, and setting the winding speed to 40m/min when the fluffy coarse fiber melt-blowing cloth is received and formed. Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set to 65g/kg (dry air), and the temperature in the region was set to 110 ℃. Further, in the space region, the fiber yarn was sprayed using a spraying device, the spraying pressure was set to 0.7MPa, the spraying angle was set to 90 °, the spraying temperature was 20 ℃, the spraying flow rate was 300ml/min, and the center-to-center distance between the nozzle of the spraying system and the spinneret plate was set to 30cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.5mm, the aspect ratio of the spinneret orifices was set to 30, the length of the spinneret plate was 1350mm, the number of the spinneret orifices was set to 3000, the spacing between the spinneret orifices was set to 0.8mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.5ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane where the spinneret hole is arranged is 1mm, the temperature of hot air generated by the air knives is 300 ℃, the wind pressure is 180kPa, and the air quantity of the hot air is 19m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 75 degrees. And when the fiber yarn spray paper is formed in the step S3, an air suction device (such as an exhaust fan and the like) is further arranged on one side of the winding net curtain, which is away from the forming side, and the air suction device is started while the melt-blown fabric is formed so as to prevent the formation of flying.

The fluffy coarse fiber melt-blown cloth prepared by the above scheme has a thickness of 798 μm, 16 fluffy coarse fiber melt-blown cloths are stacked, a force of 757Pa is applied to the surface of the fluffy coarse fiber melt-blown cloth, and after the fluffy coarse fiber melt-blown cloth is compressed, the thickness reduction amount of the fluffy coarse fiber melt-blown cloth is 69%. And the diameter of the coarse fiber yarn is 37 mu m, the diameter of the fine fiber yarn is 5 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. Measurement of fiber diameterThe measuring method comprises the steps of carrying out morphology characterization on the melt-blown non-woven fabric by using a scanning electron microscope, and then measuring by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure a breaking strength of 38N for meltblown. Further measurable grammage of the fluffy coarse fiber melt-blown cloth is 60g/m ² The ventilation is 8366mm/s.

Embodiment seven:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials are mixed, and polypropylene with a melt index of 1900g/10min and polypropylene with a melt index of 28g/10min are mixed, wherein the content of the polypropylene with a high melt index is 65wt% and the content of the polypropylene with a low melt index is 35wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 300mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 37m/min when the fluffy coarse fiber melt-blown cloth is formed. Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the filaments were ejected from the spinneret holes, the moisture content in the space region before molding was set to 75g/kg (dry air), and the temperature in this region was set to 120 ℃. Further, in the space region, the fiber yarn was sprayed using a spraying device, the spraying pressure was set to 0.8MPa, the spraying angle was set to 85 °, the spraying temperature was 15 ℃, the spraying flow rate was 350ml/min, and the center-to-center distance between the nozzle of the spraying system and the spinneret plate was set to 25cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.5mm, the aspect ratio of the spinneret orifices was set to 29, the length of the spinneret plate was 1250mm, the number of the spinneret orifices was set to 3100, the spacing between the spinneret orifices was set to 0.9mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.5ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane of the spinneret hole is set to be 0.9mm, the temperature of hot air generated by the air knives is set to be 300 ℃, and the wind pressure is set to be 200kPa, and the air volume of the hot air was 16m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 65 degrees. And when the fiber yarn spray paper is formed in the step S3, an air suction device (such as an exhaust fan and the like) is further arranged on one side of the winding net curtain, which is away from the forming side, and the air suction device is started while the melt-blown fabric is formed so as to prevent the formation of flying.

The fluffy coarse fiber melt-blown cloth prepared by the scheme has the thickness of 870 mu m, 16 fluffy coarse fiber melt-blown cloths are stacked, and force with the size of 757Pa is applied to the surface of the fluffy coarse fiber melt-blown cloth, and after the fluffy coarse fiber melt-blown cloth is compressed, the thickness reduction amount of the fluffy coarse fiber melt-blown cloth is 75%. The diameter of the coarse fiber yarn is 44 mu m, the diameter of the fine fiber yarn is 3 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure breaking strength of 40N for meltblown. Further measurable grammage of the fluffy coarse fiber melt-blown cloth is 60g/m ² The ventilation is 8928mm/s.

Example eight:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials were mixed, and polypropylene having a melt index of 2100g/10min and polypropylene having a melt index of 32g/10min were mixed, wherein the polypropylene content of the high melt index was 72wt% and the polypropylene content of the low melt index was 28wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 330mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 40m/min when the fluffy coarse fiber melt-blown cloth is formed. Step S3: after being sprayed out from the spinneret holes, the fiber yarn passes through a section of path in the air and is sprayed to the winding net curtain to enterAnd (5) performing forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set at 85g/kg (dry air), and the temperature in this region was set at 130 ℃. Further, in the space region, the fiber was sprayed using a spraying device, the spraying pressure was set to 0.75MPa, the spraying angle was set to 90 °, the spraying temperature was 27 ℃, the spraying flow rate was 400ml/min, and the center-to-center distance between the nozzle of the spraying system and the spinneret was set to 37cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.5mm, the aspect ratio of the spinneret orifices was set to 29, the length of the spinneret plate was 1150mm, the number of the spinneret orifices was set to 3200, the spacing between the spinneret orifices was set to 1mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.5ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane of the spinneret hole is 1mm, the temperature of hot air generated by the air knives is 295 ℃, the wind pressure is 190kPa, and the air quantity of the hot air is 24m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 60 degrees. And when the fiber yarn spray paper is formed in the step S3, an air suction device (such as an exhaust fan and the like) is further arranged on one side of the winding net curtain, which is away from the forming side, and the air suction device is started while the melt-blown fabric is formed so as to prevent the formation of flying.

The fluffy coarse fiber melt-blown cloth prepared by the scheme has the thickness of 898 mu m, 16 fluffy coarse fiber melt-blown cloths are stacked, and force with the size of 757Pa is applied to the surface of the fluffy coarse fiber melt-blown cloth, and after the fluffy coarse fiber melt-blown cloth is compressed, the thickness reduction amount of the fluffy coarse fiber melt-blown cloth is 80%. And the diameter of the coarse fiber yarn is 51 mu m, the diameter of the fine fiber yarn is 4 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) for melt-blowing The cloth measured breaking strength 38N. Further measurable grammage of the fluffy coarse fiber meltblown fabric was 58g/m ² The ventilation was 8847mm/s.

Example nine:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials are mixed, and polypropylene with a melt index of 2300g/10min and polypropylene with a melt index of 36g/10min are mixed, wherein the content of polypropylene with a high melt index is 84wt% and the content of polypropylene with a low melt index is 16wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 350mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 39m/min when the fluffy coarse fiber melt-blown cloth is formed. Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set to 88g/kg (dry air), and the temperature in this region was set to 140 ℃. Further, in the space region, the fiber was sprayed using a spraying device, the spraying pressure was set to 0.8MPa, the spraying angle was set to 83 °, the spraying temperature was 22 ℃, the spraying flow rate was 450ml/min, and the center-to-center distance between the nozzle of the spraying system and the spinneret was set to 31cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.4mm, the aspect ratio of the spinneret orifices was set to 19, the length of the spinneret plate was 1400mm, the number of the spinneret orifices was set to 2900, the spacing between the spinneret orifices was set to 0.8mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.5ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane where the spinneret hole is positioned is set to be 0.8mm, the temperature of hot air generated by the air knives is set to be 292 ℃, the wind pressure is set to be 195kPa, and the wind quantity of the hot air is 20m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 80 degrees. In the step S3, when the fiber yarn spray paper is formed by winding the net curtain, an air suction device (such as an exhaust fan) is also arranged on the side of the winding net curtain, which is away from the forming side, and the air suction device is opened while the melt-blown cloth is formed so as to prevent flyingIs formed by the steps of (a).

The fluffy coarse fiber meltblown cloth prepared by the above scheme has a thickness of 882 μm, 16 fluffy coarse fiber meltblown cloths are stacked, and a force of 757Pa is applied to the surface of the fluffy coarse fiber meltblown cloth, and after compression, the thickness reduction is 78%. And the diameter of the coarse fiber yarn is 77 mu m, the diameter of the fine fiber yarn is 8 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure a breaking strength of 38N for meltblown. Further measurable grammage of the fluffy coarse fiber meltblown fabric was 57g/m ² The ventilation was 8863mm/s.

Example ten:

a preparation method of fluffy coarse fiber melt-blown cloth comprises the following steps of S1: the raw materials were mixed, and polypropylene having a melt index of 2500g/10min and polypropylene having a melt index of 40g/10min were mixed, wherein the polypropylene content of the high melt index was 93.7wt% and the polypropylene content of the low melt index was 6.3wt%. Step S2: and (2) carrying out melt extrusion on the blend obtained in the step (S1) in an extruder, metering by a metering pump, drawing by an air knife, carrying out melt blowing by a spinneret plate, setting the receiving height to be 340mm when the fluffy coarse fiber melt-blown cloth is formed, and setting the winding speed to be 35m/min when the fluffy coarse fiber melt-blown cloth is formed. Step S3: after being sprayed out from the spinneret holes, the fiber filaments pass through a section of path in the air and are sprayed to the winding net curtain for forming. After the fiber was ejected from the spinneret, the moisture content in the space region before molding was set to 90g/kg (dry air), and the temperature in this region was set to 135 ℃. Further, in the space region, the fiber yarn was sprayed using a spraying device, the spraying pressure was set to 0.65MPa, the spraying angle was set to 88 °, and the spraying temperature was set to be the same as that of the spray deviceThe spray flow was 500ml/min at 16℃and the center-to-center spacing of the nozzle orifice of the spray system and the spinneret was set at 38cm. In this example, the diameter of the spinneret orifices on the spinneret plate was set to 0.3mm, the aspect ratio of the spinneret orifices was set to 22, the length of the spinneret plate was 1050mm, the number of the spinneret orifices was set to 3050, the spacing between the spinneret orifices was set to 0.8mm, and the flow rate of the blend in the molten state of the raw material in the spinneret plate was 0.5ghm. Air knives are arranged on two sides of the spinneret hole, the distance between the inclined plane of the air knives and the inclined plane of the spinneret hole is 0.8mm, the temperature of hot air generated by the air knives is 295 ℃, the wind pressure is 180kPa, and the air quantity of the hot air is 24m ³ And/min. The included angle of the V-shaped inclined plane formed by the air knives at the two sides of the spinneret hole is set to be 70 degrees. And when the fiber yarn spray paper is formed in the step S3, an air suction device (such as an exhaust fan and the like) is further arranged on one side of the winding net curtain, which is away from the forming side, and the air suction device is started while the melt-blown fabric is formed so as to prevent the formation of flying.

The fluffy coarse fiber meltblown cloth prepared by the above scheme has a thickness of 864 μm, 16 fluffy coarse fiber meltblown cloths are stacked, and a force of 757Pa is applied to the surface of the fluffy coarse fiber meltblown cloth, and after compression, the thickness reduction amount of the fluffy coarse fiber meltblown cloth is 77%. And the diameter of the coarse fiber yarn is 67 mu m, the diameter of the fine fiber yarn is 6 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure breaking strength for meltblown fabrics as 37N. Further measurable grammage of the fluffy coarse fiber meltblown web was 54g/m ² The ventilation is 8274mm/s.

Comparative example one:

the difference between comparative example one and example one is that the method for producing a bulk coarse fiber meltblown web in step S3 had a moisture content of 2g/kg of air (dry air), the temperature in this zone was set to 50 c and the remaining conditions were the same.

The meltblown fabric prepared by the method of comparative example one, having a thickness of 361 μm, was prepared by stacking 16 pieces of the bulky crude fiber meltblown fabric, and applying a force of 757Pa to the surface thereof, and after compression, had a thickness reduction of 23%. And the diameter of the coarse fiber yarn is 7 mu m, the diameter of the fine fiber yarn is 3 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure breaking strength of 2N for meltblown. Further measurable grammage of the fluffy coarse fiber meltblown fabric was 24g/m ² The ventilation is 2148mm/s.

Comparative example two:

the difference between the second comparative example and the second example is that the method for producing a bulk coarse fiber meltblown web had a moisture content of 95g/kg of air (dry air) in step S3, the temperature in this zone was set to 150 ℃, and the other conditions were all the same.

The meltblown fabric prepared by the method of comparative example one was 593 μm thick, 16 pieces of the fluffy coarse fiber meltblown fabric were stacked, and a force of 757Pa was applied to the surface thereof, and after compression, the thickness reduction was 67%. And the diameter of the coarse fiber yarn is 33 mu m, the diameter of the fine fiber yarn is 12 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The method for measuring fiber diameter comprises performing morphology characterization of melt-blown nonwoven fabric by using scanning electron microscope, and using computer software (such as Matlab, NIS-Elements, etc) Or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure breaking strength of 27N for meltblown. Further measurable grammage of the fluffy coarse fiber meltblown fabric was 49g/m ² The ventilation is 5347mm/s.

Comparative example three:

comparative example three and example ten differ in that the method of producing a bulk coarse fiber meltblown web in step S3 had a moisture content of 120g/kg of air (dry air), the temperature in this zone was set to 180 ℃, and the remaining conditions were all the same.

The meltblown fabric prepared by the method of comparative example three, having a thickness of 1043 μm, was stacked by taking 16 pieces of the meltblown fabric of fluffy crude fibers, and applied with a force of 757Pa on the surface thereof, and after compression, had a thickness reduction of 92%. And the diameter of the coarse fiber yarn is 84 mu m, the diameter of the fine fiber yarn is 13 mu m, the diameter of the thickest part of the single fiber yarn is not more than 150% of the diameter of the thinnest part of the single fiber yarn, and meanwhile, the content of the coarse fiber yarn is more than that of the fine fiber yarn as can be seen from an electron microscope image of fluffy coarse fiber melt-blown cloth. The fiber diameter measuring method is that after the morphology of the melt-blown non-woven fabric is characterized by using a scanning electron microscope, the fiber diameter is measured by using computer software (such as Matlab, NIS-Elements and the like) or manually. Can be according to the national standard: GB/T24218.3-2010, textile, nonwoven test method, section 3, determination of breaking strength and elongation at break (bar method) to measure breaking strength of 50N for meltblown. Further measurable grammage of the fluffy coarse fiber meltblown fabric was 66g/m ² The ventilation is 9774mm/s.

As can be seen from comparing the first, second, third and first to tenth comparative examples, when the moisture content of the air in the space between the spinneret holes and the winding screen is less than 5g/kg (dry air) and the temperature in the space is less than 60 ℃, the meltblown cloth produced by the same process is relatively thin in thickness, relatively thin in fiber diameter and relatively compact in surface, and is itself low in strength, grammage and air permeability. When the moisture content of the air in the space between the spinneret holes and the winding net curtain is more than 90g/kg (dry air), and the temperature in the space is more than 140 ℃, the thickness of the melt-blown cloth prepared by the same process is relatively thicker, the diameter of the fiber wires is relatively thicker, and the surface of the melt-blown cloth is relatively loose, but the melt-blown cloth has relatively higher strength due to the larger diameter of the fiber wires, but the gram weight and the ventilation amount are increased.

Example eleven:

the fluffy coarse fiber melt-blown filter element shown in fig. 1 comprises a center rod 1 and a filter layer arranged outside the center rod 1, wherein the filter layer radially comprises a soft medium layer, an inner barrier layer arranged between the soft medium layer and the center rod 1 and used for blocking the soft medium layer from being extruded into the center rod 1, and an outer barrier layer arranged outside the soft medium layer and used for wrapping the soft medium layer so as not to be easy to scatter, and a spacer layer used for providing a dirt containing space is arranged inside the soft medium layer. The soft medium layer in this embodiment may be a pp medium layer or other polymer medium layers, more specifically, the pp medium layer is formed by winding a fluffy coarse fiber melt-blown fabric belt composite supporting net belt 2 made of pp material, and when the fluffy coarse fiber melt-blown fabric belt composite supporting net belt 2 is used, the head end and the tail end of the supporting net belt 2 are respectively kept with a certain uncomplexed length. In this way, when the fluffy coarse fiber melt-blown cloth belt and the supporting net belt 2 are compositely wound to form a soft medium layer, an inner barrier layer and an outer barrier layer are formed at the same time. Meanwhile, the supporting net belt 2 compounded on the fluffy coarse fiber melt-blown cloth belt can provide a dirt receiving space after being wound to form a spacing layer. Further in this example, pp bulk fiber meltblown tapes include three different accuracies (products in example one, example two, and example three), three different accuracies of bulk fiber meltblown tapes are respectively compounded on the same support web 2, and the high-accuracy bulk fiber meltblown tapes are disposed closer to the center rod 1 after being wound into a filter cartridge to form gradient filtration. In other embodiments, two different precision fluffy coarse fiber meltblown tapes or four different precision coarse fiber meltblown tapes or more may be selected according to different requirements. In this embodiment, the third meltblown belt 2c with the lowest precision and the first meltblown belt 2a with the highest precision are combined on the same side of the supporting mesh belt 2, while the second meltblown belt 2b with the middle precision is combined on the other side of the supporting mesh belt 2, so that the production efficiency is ensured in mechanized continuous production, and of course, the fluffy coarse fiber meltblown belts with different precision can also be arranged on the same side of the supporting mesh belt 2. And projections of the fluffy coarse fiber melt-blown tapes of different accuracies on the supporting mesh tape 2 are connected. Of course, the projections of the fluffy coarse fiber melt-blown belts with different precision on the supporting net belt 2 can be partially overlapped or arranged at intervals. In the present embodiment, the thickness of the supporting mesh belt 2 is set to 600 μm, and the supporting mesh belt 2 is a mesh structure whose mesh is woven at an angle of 85 °. Further, detection of interception efficiency is carried out on the prepared filter element, filter liquor to be filtered with the impurity particle size of 300 mu m is selected, the filter liquor to be filtered is lithium battery slurry, the viscosity of the filter liquor is 5000cps, filtration is carried out under the pressure of 1MPa, the content of the impurity particles is detected to find that the interception efficiency is 99% before and after the filter liquor is filtered, and the pressure drop is measured to be 0.3MPa.

Comparative example four:

comparative example four differs from example eleven in the selection of pp lofty coarse fiber meltblown webs of different precision (the products of, e.g., comparative example one, comparative example two, and comparative example three were selected). By the same way, the prepared filter element is subjected to interception efficiency detection, the filter element to be filtered with the impurity particle size of 300 mu m is selected, the filter element to be filtered is lithium battery slurry with the viscosity of 5000cps, the filter element is filtered under the pressure of 1MPa, the interception efficiency of the filter element to be filtered is found to be 85% before and after the filter element to be filtered is detected, and the pressure drop is measured to be 0.9MPa.

Comparing example eleven with comparative example four, it was not difficult to find a filter cartridge made of pp fluff coarse fiber meltblown with a degree of bulk that was superior to the product of comparative example four in terms of interception efficiency, service life and flow rate.

While the preferred embodiments of the present invention have been described in detail, it will be appreciated that those skilled in the art, upon reading the above teachings, may make various changes and modifications to the invention. Such equivalents are also intended to fall within the scope of the claims appended hereto.

Claims

1. The thick fiber melt-blown cloth is used for filtering lithium battery slurry and comprises fiber filaments which are mutually stacked and bonded, and is characterized in that the thickness of the thick fiber melt-blown cloth is 400-900 mu m, 16 thick fiber melt-blown cloth is stacked, and a 757Pa force is applied to the surface of the thick fiber melt-blown cloth, and the thickness of the thick fiber melt-blown cloth is 30-80% compared with the original thickness of the thick fiber melt-blown cloth; the filaments comprise coarse filaments having a diameter greater than 16 μm; the fiber yarn also comprises a fine fiber yarn, and the diameter of the fine fiber yarn is 3-9 mu m; the content of the coarse fiber filaments is more than that of the fine fiber filaments.

2. The lofty raw fiber meltblown web according to claim 1, wherein the ratio of the diameter of the raw fiber filaments to the thickness of the meltblown web is set between 1/60 and 1/10.

3. The lofty raw fiber meltblown web according to claim 1, wherein the diameter of the thickest part of the individual filaments is no more than 150% of the diameter of the thinnest part of the individual filaments.

4. The lofty fibrous meltblowing according to claim 1, wherein the lofty fibrous meltblowing has a tenacity of between 5N and 40N.

5. The bulk fibrous meltblown web according to claim 1, wherein the grammage of the bulk fibrous meltblown web is set between 30 g/-60 g/-square meter.

6. The lofty raw fiber meltblown web according to claim 1, wherein the air permeability of the lofty raw fiber meltblown web is set between 3000mm/s and 9000 mm/s.

7. A process for preparing a bulk coarse fiber meltblown web according to claim 1 to 6, comprising the steps of,

s1: mixing raw materials, namely blending one or more polymers with at least two melt indexes, wherein the content of a high melt index part in the raw materials is 65-96.5 wt% and the content of a low melt index part in the raw materials is 3.5-35 wt%;

S2: melt spinning, namely melt extruding the blend obtained in the step S1 in an extruder, measuring by a metering pump and drawing by an air knife, and melt-blowing through a spinneret orifice on a spinneret plate to form fiber filaments;

s3: and (2) receiving and forming, namely spraying the fiber yarn formed in the step (S2) on a winding net curtain for bonding and forming, wherein the moisture content of air in a space between the spinning holes and the winding net curtain is set between 5g/kg dry air and 90g/kg dry air, and the temperature in the space is set between 60 ℃ and 140 ℃.

8. The method of making a bulk fibrous meltblown according to claim 7, wherein the filaments of step S3 are subjected to a transverse force prior to bonding to the web.

9. The method of making a fluffy coarse fiber meltblown web according to claim 8, wherein the transverse force is provided by a spraying device having a spray pressure of between 0.05 MPa and 0.8MPa and a spray angle of between 30 ° and 90 °.

10. The method of producing a bulk raw fiber meltblown fabric according to claim 7, wherein the receiving height of the bulk raw fiber meltblown fabric is set between 80mm and 350mm and the winding speed of the bulk raw fiber meltblown fabric is set between 15m/min and 40 m/min.

11. The method of making a fluffy coarse fiber meltblown web according to claim 7, wherein the spinneret has orifices having diameters of between 0.1mm and 0.5mm and aspect ratios of between 15 and 30.

12. The method of making a fluffy coarse fiber meltblown web according to claim 7 or 11, wherein the spinneret has a length of between 1000mm and 1400mm, the number of orifices on the spinneret being between 2500 and 3200, and the spacing between the orifices being between 0.3mm and 1 mm.

13. The method for preparing fluffy coarse fiber melt-blown cloth according to claim 7, wherein air knives are arranged on two sides of the spinneret hole, and the distance between the inclined planes of the air knives and the inclined planes of the spinneret hole is 0.5mm-1.0 mm.

14. The method of producing a bulk coarse fiber meltblown web according to claim 7 or 13, wherein the air knife generates hot air at a temperature between 180 ℃ and 300 ℃ and a wind pressure between 20kPa and 200 kPa.

15. The method of making a fluffy coarse fiber meltblown fabric according to claim 14, wherein the air knife has a hot air volume set between 10 m/min and 25 m/min.

16. The method of making a fluffy coarse fiber meltblown web according to claim 14, wherein the air knives on both sides of the spinneret orifice form a V-shaped inclined plane having an included angle of between 60 ° and 90 °.

17. The method of making a fluffy coarse fiber meltblown web according to claim 7, wherein the blend has a flow rate in the spinneret of between 0.05 ghm and 0.5 ghm.

18. The method of preparing a fluffy coarse fiber meltblown web according to claim 9, wherein the spraying device is maintained at a spray temperature of between 15 ℃ and 30 ℃, a spray flow rate of between 80ml/min and 500ml/min, and a center-to-center spacing of the spray orifice of the spraying system and the spinneret of between 20cm and 40 cm.

19. The method of producing a bulk coarse fiber meltblown web according to claim 7, wherein the side facing away from the forming side in step S3 is provided with a suction device that is simultaneously activated in step S3.

20. A filter cartridge comprising the bulk-fiber meltblown fabric of any one of claims 1-6, comprising a central rod and a media layer of bulk-fiber meltblown fabric tape wound about the outer portion of the central rod, wherein the bulk-fiber meltblown fabric tape is wound simultaneously with a support web, and wherein the bulk-fiber meltblown fabric tape comprises at least two types of precision, the high precision bulk-fiber fabric tape being disposed closer to the central rod.

21. The bulk coarse fiber meltblown filter cartridge of claim 20, wherein the innermost side of the media layer comprises an inner barrier layer formed by a support web wrap; the outermost side of the dielectric layer comprises an outer barrier layer formed by a supporting net belt.

22. The bulk coarse fiber meltblown filter cartridge of claim 20 or 21, wherein the bulk coarse fiber meltblown strip is a single piece; or a plurality of fluffy coarse fiber melt-blown cloth belts are arranged, and the end surfaces of the adjacent fluffy coarse fiber melt-blown cloth belts are connected with each other in a projection manner on the supporting mesh belt; or the number of the fluffy coarse fiber melt-blown cloth belts is multiple, and the projection of the end surfaces of the adjacent fluffy coarse fiber melt-blown cloth belts on the supporting net belt is distributed at intervals.

23. The lofty coarse fiber meltblown filter core according to claim 20, wherein when the plurality of lofty coarse fiber meltblown strips are provided, adjacent lofty coarse fiber meltblown strips are positioned on each side of the support web.

24. The fluff coarse fiber meltblown filter cartridge of claim 23, wherein the fluff coarse fiber meltblown strips are provided in three and the first fluff coarse fiber meltblown strip has a thickness of between 600 μιη and 750 μιη and a ventilation of between 3000mm/s and 5000 mm/s; the thickness of the second fluffy coarse fiber melt-blown cloth belt is 600-850 mu m, and the ventilation quantity is 5000-7000 mm/s; the thickness of the third fluffy coarse fiber melt-blown cloth belt is 550-800 mu m, and the ventilation quantity is 6000-9000 mm/s.

25. The fluffy coarse fiber melt-blown filter element of claim 24, wherein the fluffy coarse fiber melt-blown filter element has a filtration accuracy of 300um or less and an interception efficiency of 95% or more for different filtration accuracies.

26. The coarse fiber meltblown filter cartridge of claim 20, wherein the support web has a thickness of between 600 μιη and 750 μιη, wherein the support web is uniformly provided with a mesh, and wherein the mesh has a weave angle of between 85 ° -95 °.