Composite fiber industrial wiping cloth and preparation method thereof

Abstract

The invention provides a composite fiber industrial wiping cloth and a preparation method thereof, aims to improve the hygroscopicity, dirt-removing power, durability and cleanliness of the wiping cloth, and particularly meets the cleaning requirement in a high-cleanliness environment. The method comprises the steps that PET and nylon PA6 short fibers are prepared, an A / B double-layer composite fiber net is formed through opening, carding and cross lapping, the A layer is mainly made of PA, and the B layer is mainly made of PET. Multi-section boosting entanglement is carried out through a spunlace process, and it is ensured that fiber net layers are tightly combined. Then, cleaning, dehydrating, drying and heat setting are carried out; and finally, through ultrasonic edge sealing treatment, it is guaranteed that the edges are neat. The composite fiber industrial wiping cloth disclosed by the invention is excellent in hygroscopicity, decontamination property and durability, can still keep relatively high decontamination capability and relatively long service life after being used and cleaned at a high frequency, has relatively low particle precipitation, and is suitable for being used in the high-cleanliness fields of electronics, medical treatment and the like.

Description

Technical Field

[0001] This invention relates to the field of wiping cloths, specifically to composite fiber industrial wiping cloths and their preparation methods. Background Technology

[0002] With the rapid development of modern industrial technology, especially the increasing demand in high-precision fields such as electronics, medical, and optics, the performance requirements for cleaning and wiping materials have become more stringent. In these applications, traditional wiping cloths, due to their poor moisture absorption, insufficient decontamination ability, and low durability, often fail to meet the high cleanliness requirements of delicate equipment and environments. For example, wiping cloths made of a single material, while functional in some less demanding situations, cannot provide sufficient performance guarantees in environments with extremely high surface cleanliness requirements.

[0003] Especially in high-cleanliness environments, while commonly used wiping cloths made of materials such as polyester (PET) and nylon (PA) have advantages in some aspects, they also have many shortcomings. PET wiping cloths are relatively weak in terms of moisture absorption and stain removal capabilities, especially when dealing with oily stains, ink, and other difficult-to-clean substances, where their effectiveness is less than satisfactory. On the other hand, although nylon (PA) has excellent hydrophilicity and can quickly absorb water and remove stains, its durability is poor. After frequent use, it is prone to wear and tear, lint shedding, and other problems, affecting the cleaning effect and cost-effectiveness in long-term use.

[0004] Therefore, composite fiber materials have become an effective way to solve these problems. Composite fiber industrial wiping cloths, through the rational design of combining different types of fibers, can comprehensively utilize the advantages of various fibers and improve the overall performance of the wiping cloth. In particular, the composite of polyester and nylon fibers not only improves the strength and abrasion resistance of the wiping cloth, but also enhances its moisture absorption and detergency, thus better meeting the multiple performance requirements of wiping cloths in high-cleanliness environments.

[0005] However, existing composite fiber industrial wiping cloths still face some challenges. Although composite structures offer better performance, certain issues remain regarding interlayer bonding, durability, and particle exudation. For example, traditional hydroentangling processes often fail to effectively address the problem of insufficient interlayer entanglement, leading to lint shedding during use and affecting their application in clean environments. Furthermore, the functionality and structural stability of existing composite fiber industrial wiping cloths tend to decline after frequent use and repeated washing, resulting in inconsistent performance over long-term use.

[0006] To address these challenges, the market urgently needs a new type of composite fiber industrial wiping cloth that not only provides excellent moisture absorption, detergency, and durability in short-term use, but also maintains high cleaning performance and structural stability after multiple washes. Especially in high-cleanliness environments, the cleanliness and low particulate leaching of the wiping cloth are indispensable, requiring sophisticated manufacturing processes and optimized material formulations to minimize leaching and maintain long-term high efficiency. Summary of the Invention

[0007] The purpose of this invention is to provide a composite fiber industrial wiping cloth and its preparation method to solve the problems in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] In a first aspect, the present invention provides a method for preparing a composite fiber industrial wiping cloth, comprising the following steps:

[0010] S1: Fiber preparation: Provide polyester PET staple fiber and nylon PA6 staple fiber, wherein the staple fiber has a linear density of 0.8-1.7 dtex and a length of 32-51 mm;

[0011] S2: Web Formation and Lamination: PET short fibers and PA short fibers are opened, carded, and cross-laid separately, and then laminated to form an A / B double-layer composite fiber web. The A layer, located on the wiping surface, is mainly composed of PA, with a PA mass fraction of 60-85%. The B layer is mainly composed of PET, with a PET mass fraction of 60-90%. The basis weight of the composite fiber web is 40-120 g / m².

[0012] S3: Pre-wetting and pre-hydration: The composite fiber web is pre-wetted by spraying softened water to a moisture content of 80-120%, and pre-entangled and fixed by a hydroentanglement pressure of 30-90 bar.

[0013] S4: Main hydroentanglement: Under the support of the support net, multiple stages of pressurized hydroentanglement are alternately applied to both sides of the composite fiber net. The stage pressure is 90-220 bar, the number of stages is 2-4, and the distance between the nozzle and the net surface is 20-60 mm to form an interlayer entangled structure.

[0014] S5: Cleaning and dehydration: The entangled fiber web is cleaned with 2-4 grade countercurrent pure water, and the moisture content is controlled at 60-100% through vacuum dewatering and water squeezing.

[0015] S6: Drying and heat setting: Dry the fiber web with hot air at 110-160℃ until it regains moisture by 1-3%, and then perform light hot pressing at 130-160℃ and 15-40kN / m to fix the thickness.

[0016] S7: Slitting and Sealing: The dried material is slit and sealed using ultrasonic or thermal cutting methods to obtain composite fiber industrial wiping cloth.

[0017] In one or more embodiments, the mass fractions of PA and PET in layer A are 65-80% and 35-20%, respectively, the mass fractions of PET and PA in layer B are 65-85% and 35-15%, respectively, and the basis weight of the composite fiber web is 60-90 g / m².

[0018] In one or more embodiments, the linear density of the short fibers used in layer A is 0.8-1.3 dtex, the linear density of the short fibers used in layer B is 1.1-1.7 dtex, and the length of the short fibers in layers A and B is 38±3 mm to form a fineness and coverage gradient.

[0019] In one or more embodiments, the web is formed by a double combing and cross-laying method, with a cross-laying angle of 30-60° and a lateral weight deviation controlled within ±5%.

[0020] In one or more embodiments, the main water jetting employs a three-stage pressurization, with stage pressures of 100-150-190 bar, alternating water jetting from both sides, a nozzle-to-mesh distance of 30-40 mm, and a linear velocity of 25-35 m / min.

[0021] In one or more embodiments, the conductivity of the water used for cleaning is ≤10μS / cm, preferably ≤5μS / cm, the TOC is ≤1mg / L, and the moisture content is controlled at 70-90% after three-stage countercurrent cleaning.

[0022] In one or more embodiments, the heat treatment is hot air drying at 135-150°C combined with spot calendering, the spot calendering temperature is 150-160°C, the pressure is 20-30kN / m, and the spot coverage is 5-15%.

[0023] In one or more embodiments, the slit material is ultrasonically sealed at 20-40 kHz with an amplitude of 5-40 μm; and then dried and packaged in a clean environment.

[0024] In one or more embodiments, after drying in S6, a fluorine-free, low-migration functional finishing agent is applied. The finishing agent is hydrophilic or antistatic and is applied at an amount of 0.05-0.15 wt% of the weight of the treated fiber. The fiber is then dried and set at 120-130°C. Alternatively, low precipitation and low shedding can be achieved by washing with high-purity water without applying chemical finishing.

[0025] In a second aspect, the present invention provides a composite fiber industrial wiping cloth prepared by the above-described method.

[0026] Compared with the prior art, the present invention has at least the following beneficial effects:

[0027] (1) Excellent moisture absorption and detergency: By adopting a composite structure of PA and PET, especially the hydrophilic properties of the surface PA, the composite fiber industrial wiping cloth possesses excellent moisture absorption. This structure can effectively absorb and quickly remove surface stains, improving the wiping effect, especially performing well in fields with high cleanliness requirements such as electronics and optics. In addition, the meticulous hydroentangling process ensures tight entanglement and uniform distribution between fibers, further enhancing the detergency performance.

[0028] (2) Improved durability and strength: By rationally adjusting the mass distribution and fiber fineness of layer A (PA) and layer B (PET), the composite fiber industrial wiping cloth achieves good durability and strength. The high strength characteristics of layer B PET improve the overall tear strength and abrasion resistance of the wiping cloth, extending its service life. The application of hydroentanglement technology effectively improves the fiber bonding force between layers, reduces lint shedding during wiping, and ensures long-term reliability.

[0029] (3) Precise dimensional stability and post-processing optimization: The composite fiber industrial wiping cloth has good dimensional stability by adopting a fixed-thickness hot pressing and shaping process, which avoids dimensional changes caused by friction or external force during actual use. Through high-temperature hot air drying and spot calendering, not only is the appearance and feel of the product further improved, but the smoothness and fineness of the wiping cloth surface are also improved, ensuring efficient and uniform wiping effect.

[0030] (4) Low leaching, low lint, and guaranteed cleanliness: By precisely controlling the water quality and post-processing in the cleaning steps, this method significantly reduces the leaching and lint problems of the wiping cloth, ensuring that the wiping cloth will not release excessive particles or contaminants when used in environments with high cleanliness requirements, maintaining low particle residue and good cleanliness. This advantage makes composite fiber industrial wiping cloths particularly important in applications such as precision instruments, optical equipment, and medicine.

[0031] (5) Environmental protection and safety: By using a fluorine-free, low-migration functional finishing agent, this method not only improves the antistatic and hydrophilic properties of the wiping cloth, but also avoids the use of traditional chemical finishing agents, reducing the risk of environmental pollution and meeting the requirements of green environmental protection. The low migration of the finishing agent also ensures that the wiping cloth will not have an adverse effect on the contact surface after long-term use, ensuring the safety of the product.

[0032] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Attached Figure Description

[0033] Figure 1This is a schematic diagram of the process flow for the preparation method of the present invention. Detailed Implementation

[0034] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0037] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0038] Example 1

[0039] S1: Fiber Preparation

[0040] Polyester (PET) staple fiber and nylon (PA6) staple fiber were selected, with a linear density of 1.2 dtex and a length of 38 mm. The ratio of PET staple fiber to PA6 staple fiber was 60:40 (by mass).

[0041] S2: Networking and Lamination

[0042] PET staple fibers and PA staple fibers are processed separately through opening, carding, and cross-laying to form an A / B double-layer composite fiber web, where layer A is the PA main layer (PA content 70%) and layer B is the PET main layer (PET content 75%). The basis weight of the composite fiber web is 80 g / m².

[0043] S3: Prewetting and Pre-hydration

[0044] The composite fiber web was pre-wetted to a moisture content of 90% by spraying with deionized water. Then, the fiber web structure was fixed by pre-entanglement with a hydroentanglement pressure of 60 bar.

[0045] S4: Main hydroentanglement

[0046] Supported by the support net, a three-stage pressure-increasing hydroentangling process is carried out, with stage pressures of 100 bar, 150 bar, and 190 bar. The distance between the nozzle and the net surface is 35 mm, and the linear speed is 30 m / min, ensuring that the interlayer entanglement of the two fiber nets is dense and forming a continuous entangled structure.

[0047] S5: Washing and Dehydration

[0048] The entangled composite fiber web was washed with three stages of countercurrent pure water with a conductivity of 3 μS / cm and a TOC value of 0.5 mg / L. After washing, the moisture content was controlled to 85% using vacuum dewatering and squeezing.

[0049] S6: Drying and Heat Setting

[0050] The composite fiber web is dried in hot air at 135℃ until the moisture regain is 2%, and then a spot calendering process with a pressure of 25kN / m and a temperature controlled at 150℃ is used to ensure stable thickness and a smooth surface.

[0051] S7: Cutting and Edge Sealing

[0052] The dried composite fiber industrial wiping cloth is slit and edge-sealed using 20kHz ultrasonic waves with an amplitude of 25μm to ensure burr-free edges. It is then dried and packaged in a clean environment.

[0053] Example 2:

[0054] S1: Fiber Preparation

[0055] Polyester (PET) staple fiber and nylon (PA6) staple fiber were selected. The PET staple fiber had a linear density of 1.4 dtex and a length of 40 mm, while the PA6 staple fiber had a linear density of 1.0 dtex and a length of 38 mm. The mass ratio of PET to PA6 was 55:45.

[0056] S2: Networking and Lamination

[0057] PET staple fibers and PA6 staple fibers are processed separately through opening, carding, and cross-laying to form an A / B double-layer composite fiber web. Layer A is the PA6 main layer (PA6 content is 65%), and layer B is the PET main layer (PET content is 70%). The basis weight of the composite fiber web is 70 g / m².

[0058] S3: Prewetting and Pre-hydration

[0059] The composite fiber web is pre-wetted by spraying softened water until the moisture content is 100%. Then, it is pre-entangled with a hydroentanglement pressure of 50 bar to fix the structure of the fiber web.

[0060] S4: Main hydroentanglement

[0061] Supported by a support mesh, a four-stage pressurized hydroentangling process is performed, with stage pressures of 90 bar, 120 bar, 160 bar, and 200 bar. The nozzle-to-mesh distance is 30 mm, and the linear speed is 28 m / min. This ensures uniform fiber bonding and good entanglement between the two layers.

[0062] S5: Washing and Dehydration

[0063] The water was rinsed with countercurrent pure water, with a conductivity of 4 μS / cm and a TOC value of 0.6 mg / L. After rinsing, the moisture content was controlled to 80% using vacuum suction and squeezing.

[0064] S6: Drying and Heat Setting

[0065] The composite fiber web was dried in hot air at 140°C until the moisture regain was 2.5%. Subsequently, the fiber web was shaped using a spot calendering process with a pressure of 20 kN / m and a temperature controlled at 150°C to ensure stable thickness and a smooth surface.

[0066] S7: Cutting and Edge Sealing

[0067] After drying, the composite fiber industrial wiping cloth is edge-sealed using 20kHz ultrasonic waves with an amplitude of 30μm to ensure neat, burr-free edges. The sealed product is then dried and packaged in a clean environment.

[0068] Example 3:

[0069] S1: Fiber Preparation

[0070] Polyester (PET) staple fiber and nylon (PA6) staple fiber were selected. The PET staple fiber had a linear density of 1.5 dtex and a length of 45 mm, while the PA6 staple fiber had a linear density of 1.2 dtex and a length of 40 mm. The mass ratio of PET to PA6 was 50:50.

[0071] S2: Networking and Lamination

[0072] PET staple fibers and PA6 staple fibers are processed separately through opening, carding, and cross-laying to form an A / B double-layer composite fiber web. Layer A is the PA6 main layer (PA6 content is 70%), and layer B is the PET main layer (PET content is 75%). The basis weight of the composite fiber web is 85 g / m².

[0073] S3: Prewetting and Pre-hydration

[0074] The composite fiber web was pre-wetted to a moisture content of 95% by spraying with softened water. Then, it was pre-entangled with a hydroentanglement pressure of 70 bar to ensure the initial fixation of the fiber web.

[0075] S4: Main hydroentanglement

[0076] Supported by a support mesh, a three-stage pressurized hydroentangling process is performed, with stage pressures of 110 bar, 140 bar, and 180 bar. The nozzle-to-mesh distance is 35 mm, and the linear speed is 32 m / min. This ensures a strong bond between the fibers of the two layers and uniform interlayer entanglement.

[0077] S5: Washing and Dehydration

[0078] The water was rinsed using a two-stage countercurrent pure water process, with a conductivity of 3 μS / cm and a TOC value of 0.7 mg / L. After rinsing, the moisture content was controlled to 90% through vacuum dewatering and squeezing.

[0079] S6: Drying and Heat Setting

[0080] The composite fiber web was dried in hot air at 150°C until the moisture regain was 1.8%. Then, a spot calendering process with a pressure of 30 kN / m and a temperature controlled at 155°C was used to lightly hot press the fiber web to ensure a smooth surface and dimensional stability.

[0081] S7: Cutting and Edge Sealing

[0082] After drying, the composite fiber industrial wiping cloth is ultrasonically sealed at 20kHz with an amplitude of 35μm to ensure a neat and burr-free seal. The product is then dried and packaged in a clean environment.

[0083] After drying, a fluorine-free, low-migration hydrophilic finishing agent (applied at 0.1 wt%) is applied and dried at 120°C to improve its hydrophilicity and antistatic properties.

[0084] The composite fiber industrial wiping cloths prepared in Examples 1-3 were subjected to performance tests, and the test methods are as follows:

[0085] (1) Hygroscopicity test

[0086] Detection method:

[0087] Water absorption rate: Prepare a certain amount of deionized water (e.g., 10 mL) and place the composite fiber industrial wiping cloth on a horizontal surface. Add water droplets evenly to the surface of the wiping cloth and record the time when the water droplets begin to absorb the water.

[0088] Evaluation criteria: The water absorption rate should not exceed 10 seconds, that is, the time for the water droplet to be completely absorbed should not exceed 10 seconds.

[0089] Water absorption: Weigh the dry composite fiber industrial wiping cloth (e.g., 10g). Soak it in deionized water for a certain period of time (e.g., 30 minutes), then remove the wiping cloth, gently press out the excess water, and weigh it again after absorbing water.

[0090] Evaluation criteria: The water absorption should be greater than 50% of its original weight, that is, the water absorption should be greater than half the weight of the wiping cloth.

[0091] (2) Decontamination ability test

[0092] Detection method:

[0093] Standard stain removal rate: Select typical stains (such as oil stains, ink stains, etc.). Apply a certain amount of stain (e.g., 10 mL of oily substance or ink) to a standard surface (such as glass or stainless steel plate), allow it to dry, and then wipe it with a composite fiber industrial wiping cloth. Record the surface color difference of the stain before and after wiping, and measure it using a colorimeter (e.g., ΔE value).

[0094] Evaluation criteria: The stain removal rate should reach 90% or more, that is, the stain area should be significantly reduced after wiping, and the ΔE value should reach 2 or more.

[0095] Number of stain removal cycles: Rub the stain surface repeatedly with the wiping cloth (e.g., 10 times), and measure the amount of stain removed after each wipe. Record the stain removal effect after each wipe.

[0096] Evaluation criteria: After 10 wipes, the stain removal rate should still remain above 80%.

[0097] (3) Durability testing

[0098] Detection method:

[0099] Abrasion resistance test: The abrasion resistance of the composite fiber industrial wiping cloth is tested using a Martindale abrasion tester or a Taber abrasion tester. The wiping cloth is placed on a standard abrasion surface (such as sandpaper, metal plate, etc.), and an appropriate number of revolutions and load (200 revolutions, 500g load) are set. The surface condition of the wiping cloth after abrasion is then evaluated.

[0100] Evaluation criteria: The strength of the wiping cloth should decrease by no more than 10% after wear, that is, the strength should remain above 90% of the original value during the wear process.

[0101] Tear strength: The tear strength of the composite fiber industrial wiping cloth was measured using a standard tensile testing machine (such as ASTM D1004). The sample was fixed and torn at a standard tensile speed, and the maximum tear strength was recorded.

[0102] Evaluation criteria: The tear strength should be greater than 100N to ensure that it will not tear due to external forces during use.

[0103] Tear and tensile fatigue testing: Repeated tensile tests are conducted to simulate fatigue conditions in actual use. The tests are performed using a fatigue testing machine, with periodic stretching and relaxation cycles set to simulate the normal use of the wiping cloth.

[0104] Evaluation criteria: After a certain number of stretching cycles (e.g., 500), the strength of the composite fiber industrial wiping cloth should remain above 80% of its initial value.

[0105] The test results are shown in Table 1.

[0106] Table 1

[0107]

[0108] Results analysis:

[0109] 1. Hygroscopicity

[0110] Moisture absorption is a key indicator for evaluating whether composite fiber industrial wiping cloths can quickly absorb liquids and effectively clean. According to the test results:

[0111] Water absorption rate: The water absorption rate of Examples 1 and 3 is 7 seconds, while Example 2 is slightly better, reaching 6 seconds. The water absorption rate of all examples meets the requirements for rapid moisture absorption, proving that the composite fiber industrial wiping cloth of the present invention can quickly absorb liquid and meet the application requirements for rapid cleaning.

[0112] Water absorption: The water absorption of all embodiments is higher than 55% (more than 50% of its own weight), with the water absorption of Embodiment 2 reaching 60%, which shows that the product has strong water absorption capacity and can effectively improve cleaning efficiency.

[0113] 2. Decontamination ability

[0114] Stain removal rate: The stain removal rate of all embodiments exceeded 90%, with the stain removal rates of Embodiments 2 and 3 being 94% respectively. This indicates that the composite fiber industrial wiping cloth of the present invention has excellent performance in treating oily stains in terms of stain removal ability, and the stain removal effect remains at a high level after multiple wipings, proving the high efficiency of the wiping cloth in repeated use.

[0115] Number of cleaning cycles: Experimental data shows that after 10 wiping cycles, the cleaning rate remains above 80%, indicating that the composite fiber industrial wiping cloth of the present invention has a long-lasting cleaning ability and is suitable for long-term, high-frequency cleaning tasks.

[0116] 3. Durability

[0117] Durability was evaluated to assess the strength and wear resistance of composite fiber industrial wipes during long-term use. Based on the durability test results:

[0118] Abrasion resistance: Example 1 showed the smallest decrease in strength after abrasion (5%), while Examples 2 and 3 showed decreases of 6% and 7%, respectively. These data indicate that the composite fiber industrial wiping cloth of the present invention has high abrasion resistance and maintains good strength during long-term use, making it suitable for high-frequency use scenarios.

[0119] Tear strength: The tear strength of all embodiments is greater than 100 N, which is far higher than the strength level required for daily use, further demonstrating the superior durability of the invention.

[0120] Tensile fatigue: After 500 tensile tests, the strength of the composite fiber industrial wiping cloth in all embodiments remained above 80%, indicating that the present invention has good fatigue resistance and the functionality of the wiping cloth will not be significantly reduced even after long-term stretching and repeated use.

[0121] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0122] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for preparing a composite fiber industrial wiping cloth, characterized in that, Includes the following steps: S1: Fiber preparation: Provide polyester PET staple fiber and nylon PA6 staple fiber, wherein the staple fiber has a linear density of 0.8-1.7 dtex and a length of 32-51 mm; S2: Web Formation and Lamination: PET short fibers and PA short fibers are opened, carded, and cross-laid separately, and then laminated to form an A / B double-layer composite fiber web. The A layer, located on the wiping surface, is mainly composed of PA, with a PA mass fraction of 60-85%. The B layer is mainly composed of PET, with a PET mass fraction of 60-90%. The basis weight of the composite fiber web is 40-120 g / m². S3: Pre-wetting and pre-hydration: The composite fiber web is pre-wetted by spraying softened water to a moisture content of 80-120%, and pre-entangled and fixed by a hydroentanglement pressure of 30-90 bar. S4: Main hydroentanglement: Under the support of the support net, multiple stages of pressurized hydroentanglement are alternately applied to both sides of the composite fiber net. The stage pressure is 90-220 bar, the number of stages is 2-4, and the distance between the nozzle and the net surface is 20-60 mm to form an interlayer entangled structure. S5: Cleaning and dehydration: The entangled fiber web is cleaned with 2-4 grade countercurrent pure water, and the moisture content is controlled at 60-100% through vacuum dewatering and water squeezing. S6: Drying and heat setting: Dry the fiber web with hot air at 110-160℃ until it regains moisture by 1-3%, and then perform light hot pressing at 130-160℃ and 15-40kN / m to fix the thickness. S7: Slitting and sealing: The dried material is slit and sealed by ultrasonic or thermal cutting to obtain composite fiber industrial wiping cloth.

2. The method for preparing the composite fiber industrial wiping cloth according to claim 1, characterized in that: In layer A, the mass fractions of PA and PET are 65-80% and 35-20%, respectively; in layer B, the mass fractions of PET and PA are 65-85% and 35-15%, respectively; and the basis weight of the composite fiber web is 60-90 g / m².

3. The method for preparing the composite fiber industrial wiping cloth according to claim 1, characterized in that: The linear density of the short fibers used in layer A is 0.8-1.3 dtex, and the linear density of the short fibers used in layer B is 1.1-1.7 dtex. The length of the short fibers in layers A and B is 38±3 mm to form a fineness and coverage gradient.

4. The method for preparing the composite fiber industrial wiping cloth according to claim 1, characterized in that: The web is formed by double combing combined with cross-laying, with a cross-laying angle of 30-60°, and the width-direction weight deviation is controlled within ±5%.

5. The method for preparing the composite fiber industrial wiping cloth according to claim 1, characterized in that: The main water jetting system uses a three-stage pressurization method with a stage pressure of 100-150-190 bar. Water is sprayed alternately from both sides, with a nozzle-to-net distance of 30-40 mm and a linear speed of 25-35 m / min.

6. The method for preparing the composite fiber industrial wiping cloth according to claim 1, characterized in that: The conductivity of the water used for cleaning is ≤10μS / cm, preferably ≤5μS / cm, and the TOC is ≤1mg / L. After three-stage countercurrent cleaning, the moisture content is controlled at 70-90%.

7. The method for preparing the composite fiber industrial wiping cloth according to claim 1, characterized in that: The heat treatment involves hot air drying at 135-150℃ combined with spot calendering. The spot calendering temperature is 150-160℃, the pressure is 20-30kN / m, and the spot coverage rate is 5-15%.

8. The method for preparing the composite fiber industrial wiping cloth according to claim 1, characterized in that: The slit materials are ultrasonically sealed at 20-40kHz with an amplitude of 5-40μm; and then dried and packaged in a clean environment.

9. The method for preparing the composite fiber industrial wiping cloth according to claim 1, characterized in that: After drying in S6, a fluorine-free, low-migration functional finishing agent is applied. The finishing agent is hydrophilic or antistatic and the amount applied is 0.05-0.15 wt% of the weight of the treated fiber. The fiber is then dried and set at 120-130°C. Alternatively, no chemical finishing is applied, and the fiber is washed only with high-purity water to achieve low precipitation and low shedding.

10. A composite fiber industrial wiping cloth, characterized in that, It is prepared by any of the preparation methods described in claims 1-9.

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