Anti-blocking polyester monofilament filter cloth and preparation method thereof

Abstract

The present application belongs to the technical field of industrial filter cloth, and discloses a kind of anti-blocking polyester monofilament and multifilament filter cloth and a preparation method thereof.By passing the untwisted polyester multifilament bundle through a first coating liquid, each monofilament has a dual-repellent interface; the multifilament is twisted and used as weft, the polyester monofilament is used as warp to weave the filter cloth; after the filter cloth is calendered, a second coating liquid is applied to form a hydrophilic coating. The obtained anti-blocking polyester monofilament and multifilament filter cloth solves the technical bottleneck of easy blocking and low filtration efficiency of polyester monofilament and multifilament filter cloth. When filtering slurry, liquid is easily hydrated on the hydrophilic layer of the filtration surface, preventing the intercepted particles from directly adhering to the filtration surface, thereby improving the anti-pollution and anti-blocking capacity of the filter cloth. The dual-repellent interface of the fiber gap in the multifilament allows the infiltrated oil, water, ultra-fine particles, and colloids to quickly detach, making it difficult to adhere and accumulate inside the fiber, maintaining the filtration flow, and effectively reducing the resistance of the filter press operation. The filter cloth is easy to release and unload, has a significant anti-blocking effect, a long service life, and a high filtration efficiency.

Description

Technical Field

[0001] This invention belongs to the field of industrial filter cloth technology, and specifically relates to an anti-clogging polyester monofilament filter cloth and its preparation method. Background Technology

[0002] Polyester filter cloth is an industrial filter cloth made of polyester fiber. Due to the abrasion resistance, heat resistance, high strength, dimensional stability, and cost-effectiveness of polyester fiber, polyester filter cloth has become the primary filter material in solid-liquid separation in pharmaceuticals, food, and fine chemicals, as well as in industrial dust removal and flue gas treatment. In solid-liquid separation equipment such as load-bearing filter presses and centrifuges, polyester filter cloth, with its high strength, good air permeability and drainage, easy cleaning and cake removal, and relatively low overall maintenance costs, has been widely adopted.

[0003] Based on yarn composition, polyester filter cloths are currently mainly classified into monofilament filter cloths, multifilament filter cloths, and staple fiber filter cloths. Polyester monofilament filter cloths are woven from single polyester fibers as warp and weft, resulting in a smooth surface, regular and uniform pores, high filtration efficiency, easy unloading, easy cleaning, and resistance to clogging. However, they have lower filtration precision and poorer ability to retain fine particles. Polyester multifilament filter cloths are made by twisting multiple polyester monofilaments into multifilaments and then weaving them. They have high tensile strength and high filtration precision, capable of retaining extremely fine particles, but poor air and water permeability, low filtration efficiency, and are prone to clogging. Staple fiber filter cloths use short fibers, which are short and fuzzy, resulting in a tight structure after weaving. They have good retention of fine particles, but poor air permeability, peelability, and anti-clogging performance.

[0004] In the filtration of fine chemical slurries, to simultaneously improve filtration accuracy and efficiency while preventing clogging, engineers have developed polyester monofilament and multifilament filter cloths. These cloths use single polyester fibers as warp threads, providing high strength, dimensional stability, and surface smoothness, facilitating unloading and cleaning. The use of polyester multifilaments as weft threads enhances the filter cloth's ability to retain fine particles, overcoming the insufficient accuracy of pure monofilament filter cloths.

[0005] However, in engineering applications, polyester monofilament and multifilament filter cloth still suffers from clogging, affecting filtration efficiency. Through analysis of non-regenerable filter cloth, the main reasons for clogging of polyester monofilament and multifilament filter cloth are: (1) the surface smoothness of the multifilament is poor, causing material adhesion and making it difficult to wash off and regenerate; (2) the multifilament is composed of multiple fine monofilament fibers with internal entanglement gaps. Excessively fine particles can easily get embedded in the gaps and cannot pass through, making it extremely difficult to wash away. This accumulation eventually causes internal clogging of the fibers, affecting filtration efficiency.

[0006] To solve the clogging problem of polyester monofilament and multifilament filter cloth, the commonly used technologies are mainly: (1) layering a smooth monofilament filter cloth on the filter surface of the polyester monofilament and multifilament filter cloth. Although the anti-clogging effect is good, the thickness of the filter cloth increases, the filtration resistance increases, the efficiency decreases, and the cleaning workload increases significantly. (2) coating the filter cloth surface with a hydrophobic layer, which significantly reduces the adhesion of the slurry on the filter cloth surface, makes the filter cake easier to peel off, and alleviates the clogging. However, the hydrophobic layer also hinders the wetting and permeation of water, requiring higher pressure during filter pressing, which can easily lead to filter cloth damage or particles embedding into the filter cloth pores, causing "clogging". Summary of the Invention

[0007] For a long time, hydrophobic coatings have been used to prevent clogging of filter cloths, but this increases water resistance and reduces filtration efficiency. Hydrophilic coatings can prevent particles from directly contacting the filter surface and achieve high filtration efficiency, but the water-holding capacity of the fibers means that fine particles and colloids entering the fibers cannot be removed in time, leading to their accumulation and clogging. To address the problems of easy clogging and low filtration efficiency of polyester monofilament and multifilament filter cloths in current engineering applications, this invention provides an anti-clogging polyester monofilament and multifilament filter cloth and its preparation method. By forming a double hydrophobic interface in the gaps between individual fibers inside the multifilament and a hydrophilic interface on the filter cloth surface, the filtration efficiency and anti-clogging effect of the polyester monofilament and multifilament filter cloth are significantly improved.

[0008] To achieve the aforementioned technical effects, one aspect of the present invention provides a method for preparing anti-clogging polyester monofilament filter cloth, the specific preparation method of which is as follows:

[0009] S1. A first coating liquid is obtained by dispersing organosilicon-modified polyurethane emulsion, aqueous fluorocarbon emulsion, silica sol, and octyltrimethoxysilane in a homogenizer at a mass ratio of 100:(10-20):(5-10):(3-5); a second coating liquid is obtained by dispersing aqueous epoxy resin emulsion, aqueous polyurethane dispersion, and silica sol in a homogenizer at a mass ratio of 100:(30-40):(5-10).

[0010] S2. Pass the untwisted polyester multifilament bundle through the first coating solution, so that each monofilament is thoroughly soaked in the first coating solution. After drying, each monofilament has a double hydrophobic interface. Then twist it in the S twist direction to obtain twisted polyester multifilament.

[0011] S3. Filter cloth is woven on a Dornier loom using polyester monofilament as warp and twisted polyester multifilament prepared in step S2 as weft.

[0012] S4. Feed the filter cloth into the calender, control the linear pressure to 5-10 N / mm, and calender at 100-110℃; add the curing agent to the second coating liquid and mix evenly, then use a spray gun to atomize and spray it onto the filter surface of the filter cloth to form a hydrophilic coating, dry, and roll up to obtain an anti-clogging polyester monofilament filter cloth.

[0013] Preferably, the solid content of the silicone-modified polyurethane emulsion is 30-40 wt%.

[0014] Preferably, the aqueous fluorocarbon emulsion is an anionic emulsion copolymerized from acrylate and fluororesin, with a solid content of 40-45 wt%.

[0015] Preferably, the solid content of the aqueous epoxy resin emulsion is 45-50 wt%.

[0016] Preferably, the solid content of the aqueous polyurethane dispersion is 40-50 wt%.

[0017] Preferably, the silica sol has a SiO2 content of 20-30 wt% and a particle size of <50 nm.

[0018] In the first coating solution, octyltrimethoxysilane is dispersed in an organosilicon-modified polyurethane emulsion, an aqueous fluorocarbon emulsion, and a silica sol. Octyltrimethoxysilane hydrolyzes in an aqueous environment to generate highly active silanol groups. These silanol groups undergo a condensation reaction with the hydroxyl groups in the silica sol, forming a stable, wear-resistant, and smooth hydrophobic and oleophobic interface on the surface of each monofilament of the polyester multifilament bundle, in conjunction with the organosilicon-modified polyurethane and the aqueous fluorocarbon emulsion. This creates a low surface energy barrier at the fiber gaps within the polyester multifilament, providing dual hydrophobicity. When oil, water, fine particles, or adhesive particles penetrate the fibers, they quickly pass through, preventing the adhesion and aggregation of fine particles between fibers, thus maintaining unobstructed pores and effectively reducing pressure differential and energy consumption during equipment operation.

[0019] In the second coating solution, an aqueous epoxy resin emulsion, an aqueous polyurethane dispersion, and a silica sol are applied to the filter surface of the filter cloth to form a wear-resistant, smooth, hydrophilic interface. During filtration, the slurry directly contacts the filter surface, easily forming a hydration layer that prevents solid particles from adhering to the filter cloth surface, thereby significantly improving the filter cloth's resistance to contamination and clogging.

[0020] Preferably, the linear density of the untwisted polyester multifilament bundle in step S2 is 800-1100 dtex / 75f.

[0021] Preferably, when using the first coating liquid in step S2, water is added appropriately to control the viscosity of the first coating liquid at 10-20s (Ford-4 cup, 25°C) to avoid excessive viscosity causing liquid film adhesion between individual fibers.

[0022] Preferably, the drying in step S2 involves rapidly evaporating surface volatiles at 60-80°C, followed by curing with enhanced hot airflow at 110-120°C, resulting in a smooth interfacial film on the surface of each single fiber.

[0023] Preferably, the twist in step S2 is 80-100 twists / 10cm. This maintains a good porosity between fibers and makes the surface of the twisted polyester multifilament smooth.

[0024] Preferably, the diameter of the polyester monofilament in step S3 is 0.1-0.4 mm; the breaking strength of the polyester monofilament is >5 cN / dtex.

[0025] Preferably, the woven filter cloth in step S3 has a weave structure of either plain weave or twill weave. More preferably, the woven filter cloth has a plain weave structure. Plain weave filter cloths have smooth surfaces, good wear resistance, and high filtration accuracy. By forming a double hydrophobic interface through multifilaments and a hydrophilic layer on the filter cloth surface, the problem of easy clogging is solved, resulting in better overall performance.

[0026] Preferably, the filter cloth in step S3 has a warp density of 150-160 threads / 10cm and a weft density of 80-100 threads / 10cm.

[0027] Preferably, the speed of the calender in step S4 is uniformly controlled at 10-15 m / min. After calendering, the filter cloth has a dense and stable pore size, is not easily deformed, has a smoother surface, the filter cake is easier to remove, has strong anti-pollution ability, and is not easily clogged.

[0028] Preferably, in step S4, when the curing agent is added to the second coating liquid, the amount of curing agent added is 5-8% of the mass of the aqueous epoxy resin emulsion in the second coating liquid. The curing agent is at least one of triethylenetetramine and diethylenetriamine.

[0029] Preferably, the amount of hydrophilic coating applied in step S4 is controlled at 30-50 g / m². 2 .

[0030] In another aspect, the present invention provides an anti-clogging polyester monofilament filter cloth prepared by the above method. Thus, during slurry filtration, the hydrophilic layer allows the filtrate to quickly and readily wet the filter cloth surface, reducing direct adhesion between solid particles and the filter cloth. Large particles are intercepted on the filter cloth surface to form a peelable filter cake, preventing them from easily embedding into the interfiber spaces of the filter cloth. When excessively fine particles or filtrate become embedded in the interfiber spaces, they do not easily accumulate at the bihydrophobic interface of the fiber spaces and are promptly expelled, thereby maintaining unobstructed pores.

[0031] The beneficial effects of this invention are reflected in:

[0032] 1. This invention solves the technical bottlenecks of easy clogging and low filtration efficiency in polyester monofilament and multifilament filter cloths by treating the internal fibers of the multifilament with double hydrophobicity and the filter cloth surface with hydrophilicity. When filtering slurry, the liquid easily forms a hydration layer on the hydrophilic layer of the filter surface, preventing intercepted particles from directly adhering to the filter surface, thereby improving the filter cloth's resistance to contamination and clogging. If excessively fine particles, colloids, etc., penetrate into the filter cloth, the double hydrophobic interface of the fiber gaps inside the multifilament allows the penetrated oil, water, ultrafine particles, colloids, etc., to quickly detach, making them less likely to adhere and accumulate inside the fibers, maintaining smooth filtration and effectively reducing the resistance of the filter press operation.

[0033] 2. The anti-clogging polyester monofilament filter cloth of this invention has high water permeability, can operate at lower filtration pressures, avoids clogging caused by excessive pressure damaging the filter cloth and forced embedding of particles, facilitates cake removal and discharge, and exhibits significant regeneration performance. This greatly extends the service life of the filter cloth and improves filtration production efficiency.

[0034] 3. The anti-clogging polyester monofilament filter cloth of this invention is prepared using a mature Dornier weaving production line, and can be mass-produced by configuring coating treatment equipment. Attached Figure Description

[0035] Figure 1 This is a microscopic image of the surface of the filter cloth after 4 weeks of operation in Example 1.

[0036] Figure 2 This is a microscopic image of the surface of the filter cloth after 4 weeks of operation in Comparative Example 1.

[0037] Figure 3 This is a microscopic image of the surface of the filter cloth after 4 weeks of operation in Comparative Example 2.

[0038] Figure 4 This is a microscopic image of the surface of the filter cloth after 4 weeks of pressure filtration in Comparative Example 3. Detailed Implementation

[0039] To make the technical solution and advantages of this application clearer, the technical solution of this application will be clearly and completely described below in conjunction with embodiments. Obviously, the described embodiments are only a part of this application. It should be noted that, unless specific conditions are specified in the embodiments, they are all conventional raw materials or process conditions that can be understood by those skilled in the art.

[0040] Specifications of some raw materials:

[0041] Silicone-modified polyurethane emulsion: SILIKOPUR® 8081, 33% silicone content, 30wt% solids content, water-based, Evonik.

[0042] Aqueous fluorocarbon emulsion: RF-101, fluorine content 10%, anionic emulsion, solid content 45wt%, Fuxin Ruifeng Fluorochemical Co., Ltd.

[0043] Polyester monofilament: diameter 0.2mm, breaking strength 6.2cN / dtex.

[0044] Untwisted polyester multifilament bundle: linear density 820dtex / 75f, FDY fully drawn polyester multifilament.

[0045] Example 1

[0046] S1. A first coating liquid is obtained by dispersing organosilicon-modified polyurethane emulsion, aqueous fluorocarbon emulsion, silica sol (SiO2 content 25wt%, particle size <50nm) and octyltrimethoxysilane at a mass ratio of 100:15:5:5 in a homogenizer at 6000 rpm for 5 min; a second coating liquid is obtained by dispersing aqueous epoxy resin emulsion (solid content 45wt%), aqueous polyurethane dispersion (solid content 40wt%), and silica sol (SiO2 content 25wt%, particle size <50nm) at a mass ratio of 100:30:10 in a homogenizer at 6000 rpm for 3 min.

[0047] S2. Adjust the viscosity of the first coating solution to 20s (Ford-4 cup, 25℃) with water. Then, spread the untwisted polyester multifilament bundle and spread it through the airflow. Pass it through the first coating solution so that each monofilament is thoroughly soaked in the first coating solution. At 80℃, the surface volatiles are rapidly evaporated. Then, at 120℃, the surface is cured by a strong hot airflow to form a smooth double-repellent interface on the surface of each monofilament. Then, twist it in the S twist direction with a twist of 80 twists / 10cm to obtain twisted polyester multifilament.

[0048] S3. Using polyester monofilament as warp and twisted polyester multifilament prepared in step S2 as weft, a plain weave filter cloth is woven on a Dornier loom; the warp density is 150 threads / 10cm and the weft density is 90 threads / 10cm.

[0049] S4. Feed the filter cloth into the calender, maintaining a uniform feed speed of 15 m / min and a linear pressure of 8 N / mm, and calender at 110℃; add the curing agent triethylenetetramine to the second coating liquid and mix thoroughly, with the addition amount being 5% of the mass of the water-based epoxy resin emulsion in the second coating liquid, and then atomize and spray it onto the filter surface of the filter cloth using a spray gun, controlling the spraying amount to 40 g / m. 2 A hydrophilic coating is formed, and after being completely dried and cured at 110℃, it is wound up to obtain an anti-clogging polyester monofilament filter cloth.

[0050] Example 2

[0051] S1. A first coating liquid is obtained by dispersing organosilicon-modified polyurethane emulsion, aqueous fluorocarbon emulsion, silica sol (SiO2 content 25wt%, particle size <50nm) and octyltrimethoxysilane at a mass ratio of 100:20:10:3 in a homogenizer at 6000 rpm for 5 min; a second coating liquid is obtained by dispersing aqueous epoxy resin emulsion (solid content 45wt%), aqueous polyurethane dispersion (solid content 40wt%), and silica sol (SiO2 content 25wt%, particle size <50nm) at a mass ratio of 100:40:10 in a homogenizer at 6000 rpm for 3 min.

[0052] S2. Adjust the viscosity of the first coating solution to 15s (Ford-4 cup, 25℃) with water. Then, spread the untwisted polyester multifilament bundle and spread it through the airflow. Pass it through the first coating solution so that each monofilament is thoroughly soaked in the first coating solution. At 80℃, the surface volatiles are rapidly evaporated. Then, at 110℃, the surface is cured by a strong hot airflow to form a smooth double-repellent interface on the surface of each monofilament. Then, twist it in the S twist direction with a twist of 100 twists / 10cm to obtain twisted polyester multifilament.

[0053] S3. Using polyester monofilament as warp and the twisted polyester multifilament prepared in step S2 as weft, a plain weave filter cloth is woven on a Dornier loom; the warp density is 150 threads / 10cm and the weft density is 100 threads / 10cm.

[0054] S4. Feed the filter cloth into the calender, maintaining a uniform feed speed of 15 m / min and a linear pressure of 10 N / mm, and calender at 100℃; add the curing agent diethylenetriamine to the second coating liquid and mix thoroughly, with the addition amount being 8% of the mass of the water-based epoxy resin emulsion in the second coating liquid, and then atomize and spray it onto the filter surface of the filter cloth using a spray gun, controlling the spraying amount to 50 g / m. 2 A hydrophilic coating is formed, and after being completely dried and cured at 110℃, it is wound up to obtain an anti-clogging polyester monofilament filter cloth.

[0055] Example 3

[0056] S1. A first coating liquid is obtained by dispersing organosilicon-modified polyurethane emulsion, aqueous fluorocarbon emulsion, silica sol (SiO2 content 25wt%, particle size <50nm) and octyltrimethoxysilane at a mass ratio of 100:10:10:4 in a homogenizer at 6000 rpm for 5 min; a second coating liquid is obtained by dispersing aqueous epoxy resin emulsion (solid content 45wt%), aqueous polyurethane dispersion (solid content 40wt%), and silica sol (SiO2 content 25wt%, particle size <50nm) at a mass ratio of 100:35:5 in a homogenizer at 6000 rpm for 3 min.

[0057] S2. Adjust the viscosity of the first coating solution to 10s (Ford-4 cup, 25℃) with water. Then, spread the untwisted polyester multifilament bundle and spread it through the airflow. Pass it through the first coating solution so that each monofilament is thoroughly soaked in the first coating solution. At 80℃, the surface volatiles evaporate rapidly. Then, at 120℃, strengthen the curing by blowing with a hot airflow to form a smooth double-repellent interface on the surface of each monofilament. Then, twist it in the S twist direction with a twist of 80 twists / 10cm to obtain twisted polyester multifilament.

[0058] S3. Using polyester monofilament as warp and twisted polyester multifilament prepared in step S2 as weft, a plain weave filter cloth is woven on a Dornier loom; the warp density is 160 threads / 10cm and the weft density is 80 threads / 10cm.

[0059] S4. Feed the filter cloth into the calender, maintaining a uniform feed speed of 10 m / min and a linear pressure of 10 N / mm, and calender at 110℃; add the curing agent triethylenetetramine to the second coating liquid and mix thoroughly, with the addition amount being 6% of the mass of the water-based epoxy resin emulsion in the second coating liquid, and then atomize and spray it onto the filter surface of the filter cloth using a spray gun, controlling the spraying amount to 30 g / m. 2 A hydrophilic coating is formed, and after being completely dried and cured at 110℃, it is wound up to obtain an anti-clogging polyester monofilament filter cloth.

[0060] Comparative Example 1

[0061] In Example 1, the second coating liquid was not sprayed onto the filter cloth surface, while the remaining steps remained unchanged, and this sample served as Comparative Example 1.

[0062] Comparative Example 2

[0063] In Example 1, the step of coating the polyester multifilament with the first coating liquid was omitted, while the remaining steps remained unchanged, and this was used as the sample for Comparative Example 2.

[0064] Comparative Example 3

[0065] In Example 1, the steps of applying the first coating liquid and the second coating liquid were omitted, while the remaining steps remained unchanged, and this was used as the sample for Comparative Example 3.

[0066] (a) Air permeability test of filter cloth

[0067] Referring to GB / T 5453-2025 "Determination of Air Permeability of Textile Fabrics", 200 Pa was used as the reference pressure difference to test the initial air permeability of the filter cloth. The filter cloth was used for pressure filtration of fine chemical slurry (solids separated from aqueous mother liquor, with a particle size > 50 μm). After each cake discharge, the surface was backwashed. After 4 weeks of operation (approximately 220 pressure filtrations under the same conditions), the filter cloth was deeply rinsed, dried by backwashing with 5 bar high-pressure air, and the air permeability was tested again. See Table 1.

[0068] Table 1:

[0069]

[0070] Table 1 shows the gas permeability of the filter cloth before and after use, directly reflecting the filtration speed, efficiency, and degree of permanent clogging. The filter cloths obtained in Examples 1-3 maintained high air permeability, indicating no significant clogging, easy cleaning, and good regenerability.

[0071] After four weeks of filter cloth filtration in Example 1, the surface of the filter cloth was observed under a microscope (e.g., Figure 1 The filter cloth has an intact overall structure, with no deformation, no wear or burrs, and very few large particles remaining on the surface, exhibiting good regenerability.

[0072] The filter cloth in Comparative Example 1 did not have a hydrophilic layer coated on its filter surface. After 4 weeks of pressure filtration, the surface of the filter cloth was observed under a microscope (e.g., Figure 2 Despite a significant increase in surface adhesion of the multifilament, the air permeability still meets the requirements for engineering applications.

[0073] The filter cloth in Comparative Example 2 did not undergo double-repellent treatment on the multifilaments. After 4 weeks of pressure filtration, the surface of the filter cloth was observed under a microscope (e.g. Figure 3 The multifilament fibers in the weft and the pores contain a large number of fine particles, reducing the air permeability by more than 30%. According to engineering requirements, it no longer meets the technical conditions for engineering filtration.

[0074] The filter cloth in Comparative Example 3 was neither treated with a double-hydrophobic coating on the multifilaments nor with a surface hydrophilic treatment. After 4 weeks of pressure filtration, the surface of the filter cloth was observed under a microscope (e.g., Figure 4 The multifilament fibers in the weft and the pores form a dense blockage and "stuffing". The air permeability decreases by more than 40%, and according to engineering requirements, it no longer meets the technical conditions for engineering filtration. Moreover, wear appears on the surface of the filter cloth, mainly due to the wear caused by the filtration resistance resulting from the blockage.

[0075] (II) Filter cloth water permeability test

[0076] Corn starch was prepared into a 20% starch slurry. The filter cloths from Examples 1-3 and Comparative Examples 1-3 were installed in filtration apparatuses. 500 ml of starch slurry was added to the filtration apparatus, and the mixture was allowed to filter naturally under normal pressure. The filtrate was collected in beakers, and the amount of filtrate collected at 10 min, 20 min, and 30 min was measured. A higher filtrate collection rate at the same time interval indicates better water permeability and a higher filtration rate; a lower filtrate collection rate indicates a lower filtration rate, meaning the filtrate water does not easily wet the filter cloth, or that adsorption occurs within the filter cloth. See Table 2.

[0077] Table 2:

[0078]

[0079] The filter cloth of this invention has a liquid affinity, allowing the filtrate to penetrate quickly, reducing filtration resistance and improving solid-liquid separation efficiency. Furthermore, the double-hydrophobic interface within the fiber gaps of the filter cloth multifilament allows infiltrated water and small amounts of starch particles to quickly detach, preventing them from adhering and accumulating inside the fibers, thus maintaining unobstructed filtration and high filtration efficiency. Comparative Example 3 uses a conventional polyester monofilament filter cloth, which has poor wettability when filtering starch slurry, and the filtrate tends to retain water after entering the filter cloth fibers, making rapid permeability difficult and resulting in poor water permeability.

[0080] Based on the technical concept of forming a double hydrophobic interface inside the multifilament and forming a hydrophilic layer on the filter cloth surface to prevent clogging and improve filtration efficiency, any simple substitutions made by those skilled in the art without additional creative effort are within the scope of protection of this application.

Claims

1. A method for preparing an anti-clogging polyester monofilament and multifilament filter cloth, characterized in that, The specific preparation method is as follows: S1. A first coating liquid is obtained by dispersing organosilicon-modified polyurethane emulsion, aqueous fluorocarbon emulsion, silica sol, and octyltrimethoxysilane in a homogenizer at a mass ratio of 100:(10-20):(5-10):(3-5); a second coating liquid is obtained by dispersing aqueous epoxy resin emulsion, aqueous polyurethane dispersion, and silica sol in a homogenizer at a mass ratio of 100:(30-40):(5-10). S2. Pass the untwisted polyester multifilament bundle through the first coating solution, so that each monofilament is thoroughly soaked in the first coating solution. After drying, each monofilament has a double repellent interface. Then twist it in the S twist direction to obtain twisted polyester multifilament. S3. Filter cloth is woven on a Dornier loom using polyester monofilament as warp and twisted polyester multifilament prepared in step S2 as weft. S4. Feed the filter cloth into the calender, control the linear pressure to 5-10 N / mm, and calender at 100-110℃; add the curing agent to the second coating liquid and mix evenly, then use a spray gun to atomize and spray it onto the filter surface of the filter cloth to form a hydrophilic coating, dry, and roll up to obtain an anti-clogging polyester monofilament filter cloth.

2. The method for preparing an anti-clogging polyester monofilament filter cloth according to claim 1, characterized in that, The organosilicon-modified polyurethane emulsion has a solid content of 30-40 wt%; the waterborne fluorocarbon emulsion is an anionic emulsion copolymerized from acrylate and fluororesin, with a solid content of 40-45 wt%; the waterborne epoxy resin emulsion has a solid content of 45-50 wt%; the waterborne polyurethane dispersion has a solid content of 40-50 wt%; and the silica sol has a SiO2 content of 20-30 wt% and a particle size of <50 nm.

3. The method for preparing an anti-clogging polyester monofilament filter cloth according to claim 1, characterized in that, The linear density of the untwisted polyester multifilament bundle in step S2 is 800-1100 dtex / 75f; the twist is 80-100 twists / 10cm.

4. The method for preparing an anti-clogging polyester monofilament filter cloth according to claim 1, characterized in that, The diameter of the polyester monofilament in step S3 is 0.1-0.4 mm; the breaking strength of the polyester monofilament is >5 cN / dtex.

5. The method for preparing an anti-clogging polyester monofilament filter cloth according to claim 1, characterized in that, The woven filter cloth described in step S3 has a weave structure of either plain weave or twill weave.

6. The method for preparing an anti-clogging polyester monofilament filter cloth according to claim 1, characterized in that, The filter cloth described in step S3 has a warp density of 150-160 threads / 10cm and a weft density of 80-100 threads / 10cm.

7. The method for preparing an anti-clogging polyester monofilament filter cloth according to claim 1, characterized in that, In step S4, the speed of the calender is 10-15 m / min.

8. The method for preparing an anti-clogging polyester monofilament filter cloth according to claim 1, characterized in that, When the curing agent is added to the second coating liquid in step S4, the amount of curing agent added is 5-8% of the mass of the waterborne epoxy resin emulsion in the second coating liquid; the curing agent is at least one of triethylenetetramine and diethylenetriamine.

9. The method for preparing an anti-clogging polyester monofilament filter cloth according to claim 1, characterized in that, In step S4, the amount of hydrophilic coating applied is controlled at 30-50 g / m². 2 .

10. A clog-resistant polyester monofilament filter cloth obtained by the preparation method according to any one of claims 1-9.

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