A continuous knitting weaving process of high-performance anti-cut composite fabric and products thereof

Abstract

This invention relates to the technical field of composite fabric weaving, and discloses a continuous knitting process for high-performance cut-resistant composite fabrics and its products. The continuous knitting process for high-performance cut-resistant composite fabrics includes the following steps: online impregnation and monofilament-level interface construction, pre-curing and preliminary shaping, multi-level gradient physical shaping, secondary curing and setting, constant tension balance weaving, and selective soaping and setting. This continuous knitting process for high-performance cut-resistant composite fabrics solves the problems of difficult loop formation, frequent filament breakage, and high equipment wear caused by the high modulus and low elongation of high-performance fibers with a breaking strength ≥20cN / dtex during knitting. Furthermore, through the synergistic effect of "online interface modification + gradient physical shaping + stress balance weaving," it achieves efficient and stable production of high-performance protective composite materials while retaining the high moisture permeability, breathability, comfort, and softness of the knitted fabric.

Description

Technical Field

[0001] This invention relates to the technical field of composite fabric weaving, and in particular to a continuous knitting process for high-performance cut-resistant composite fabrics and its products. Background Technology

[0002] Many outdoor enthusiasts often face risks of cuts and punctures during hiking, camping, rock climbing, and exploration, and more and more people are realizing the importance of personal protective equipment. Therefore, there is an urgent need for special fabrics with puncture and cut resistance while retaining the characteristics of conventional fabrics such as breathability, comfort, and softness.

[0003] Common raw materials for preparing stab-resistant and cut-resistant composite materials generally use high-performance fibers such as ultra-high molecular weight polyethylene fiber, aramid fiber, and polyimide fiber. These fibers possess extremely high specific strength and specific modulus, generally with a fiber strength exceeding 20 CN / dtex. During weaving, these fibers are highly sensitive to bending and friction, easily leading to fuzzing and filament breakage. Secondly, due to their smooth surface and high resistivity, static electricity accumulates during processing, causing fiber dispersion and adhesion to machine parts. Finally, the low coefficient of friction on the fiber surface results in poor cohesion between fibers within the yarn. Traditional bulletproof, stab-resistant, and explosion-proof composite materials primarily employ unidirectional fabric (UD fabric) weaving technology. The core process involves bonding flat, spread-out fiber filaments with resin and applying 0-degree and 90-degree orthogonal lamination. UD fabric composites prepared using this process are plate-like or sheet-like, lacking multi-directional extensibility, and the resin completely covers the fiber gaps, lacking moisture permeability and breathability. Dry fabrics made from original high-performance fibers that are then treated with surface impregnation with resin liquid, shear-thickening liquid, or surface coating with resin film also become stiff or lose their moisture-permeable and breathable properties, resulting in a decline in wearability. Summary of the Invention

[0004] This invention proposes a continuous knitting process and finished products for high-performance cut-resistant composite fabrics, aiming to solve the technical bottlenecks in knitting high-performance fibers with a breaking strength ≥20cN / dtex, such as difficulties in loop formation, frequent fiber breakage, and high equipment wear caused by high modulus and low elongation. This invention achieves efficient and stable production of high-performance protective composite materials by synergistically combining online interface modification, gradient physical shaping, and stress-balanced weaving, while retaining the high moisture permeability, breathability, comfort, and softness of the knitted fabric.

[0005] The technical solution of this invention is as follows: a continuous knitting process for high-performance cut-resistant composite fabrics, comprising the following steps: online impregnation and monofilament-level interface construction: using transient expansion technology to dynamically expand high-performance fiber bundles to an ultra-thin strip shape with a monofilament layer thickness ≤ 5 layers; using relatively set elastic pressure plates to squeeze the passing filament bundles, and simultaneously impregnating the interface adhesion medium; pre-curing and preliminary shaping: the impregnated filament bundles enter the first-stage drying tunnel for pre-curing, with the temperature controlled at 70-100℃ for 10-30s, so that the resin forms a viscoelastic transient protective film on the fiber surface, and the resin and yarn form a stable mechanical anchoring structure, thus preparing a pre-cured composite yarn; multi-level gradient physical Shaping: The pre-cured composite yarn continuously passes through 2-6 tension guides with circular central cavities. The cavity size of the tension guides decreases gradually along the running direction. Multi-axial orthogonal tension is used to physically compress and shape the yarn, forcibly constraining its cross-sectional shape ratio within a quasi-circular range of 1.0-1.5:1.0, eliminating the flat, ribbon-like structure of the original high-performance fiber. The size of the circular central cavity of the tension guide is 100-200% of the fineness of the original high-performance fiber filament bundle. The size of the circular cavities of multiple tension guides gradually decreases from 200% to 100% from the input to the output. The inner wall of the central cavity of the tension guide is coated with a self-lubricating ceramic layer or a diamond-like coating. The tension guide... If only one tension guide is selected, the interface reshaping effect on the pre-cured composite yarn is limited, making it difficult to directly shape it into a near-circular shape in one step. If too many tension guides are used, production costs increase significantly, and production efficiency decreases. Two to six tension guides are sufficient to shape the pre-cured composite yarn into a near-circular shape. Secondary curing and setting: The shaped near-circular composite yarn enters the second-stage drying tunnel for secondary curing. The curing temperature is controlled at 100-160℃ for 10-60 seconds to lock the geometric shape of the fiber bundles, obtaining a high-performance composite yarn after curing. Constant tension balancing weaving: The obtained high-performance composite yarn after curing is transported to the yarn storage mechanism of the knitting equipment through a closed yarn guide tube for a predetermined number of turns. The fabric is wound and the knitting machine is started for weaving. During the winding process, the tension balance of the fabric is adjusted by a non-uniform diameter take-up mechanism to obtain the initial composite fabric. The non-uniform diameter take-up mechanism adopts an arc-shaped structure with a middle diameter larger than the diameters at both ends by 0.05-3.0 mm to offset the high resilience stress of the high-performance fibers. Selective soaping and setting: The initial fabric is treated with a soaping mixture containing emulsifiers and oxidants to selectively remove the machine oil and surface residue generated during the weaving process, while retaining the interfacial resin film inside the fibers and on the surface. After selective soaping, the resin matrix retention rate between the fibers of the composite fabric is ≥90%. After drying and setting, a puncture-resistant and cut-resistant composite fabric with good air permeability and multi-directional extensibility is obtained.

[0006] Preferably, the interfacial adhesion medium is a modified water-washable polyurethane resin with a viscosity of 10-300 mPa·s, to ensure that it can deeply penetrate into the gaps between the monofilaments inside the fiber filament bundle and form a stable micron-level mechanical anchoring structure between the internal monofilaments and the resin. The effective residence time is 1-20 s, and the high exposed specific surface area enables the modified polyurethane resin to instantly fill the gaps between the monofilaments.

[0007] Preferably, the high-performance fiber includes ultra-high molecular weight polyethylene fiber, aramid fiber, and polyimide fiber used for weaving yarn, with a fiber strength greater than 20 cn / dtex and a specific modulus greater than 400 cn / dtex.

[0008] Preferably, the elastic pressure plate is a high-flatness elastic pressure plate with a length of 20-100mm, and the initial gap d between two oppositely arranged elastic pressure plates is set to 0.5-1.5 times the original diameter D of the high-performance fiber bundle.

[0009] Preferably, the transient expansion process includes: passing high-performance fiber bundles sequentially through a set of expansion rollers with Teflon surfaces, and using the mechanical friction of the expansion rollers or the vibration generated by ultrasonic waves to expand the original cylindrical or rope-shaped filament bundles into a ribbon shape; and then reshaping the pre-cured composite yarn into a quasi-circular shape through multi-level gradient physical shaping.

[0010] Preferably, during the online impregnation process, a constant pressure is applied by elastic plates, maintaining the actual working gap between them at 0.8-1.2 times the fiber bundle diameter. If the gap between the elastic plates is less than 0.5 times the original diameter D of the high-performance fiber bundle, the fiber bundle is easily damaged, resulting in severe filament breakage or deformation. If the gap between the elastic plates is greater than 1.5 times the original diameter D of the high-performance fiber bundle, the applied force from the elastic plates is insufficient, making it difficult for the resin solution to penetrate deeply.

[0011] Preferably, the cavity size of the tension guide gradually decreases from 200% to 100% of the fiber fineness along the running direction; the cross-sectional shape ratio is the ratio of the major axis to the minor axis.

[0012] Preferably, the fabric roller in the non-equal diameter winding mechanism is designed as an arc-shaped roller with a slightly larger diameter in the middle and a gradually decreasing diameter at both ends, with the diameter of the middle section being 0.05-3.0 mm larger than the diameters at both ends. Since high-performance fibers have high strength, unevenness is easily caused during winding. However, the non-equal diameter winding roller design solves the stress concentration problem of high-performance fiber fabrics and balances the stress on the fabric surface.

[0013] Preferably, the drying and setting process involves setting the soaped composite fabric with a hot roller, with the temperature controlled at 70-100℃ and the speed at 5-10 M / min.

[0014] A high-performance cut-resistant composite fabric product is made using a continuous knitting process for high-performance cut-resistant composite fabric. The application fields of the cut-resistant composite fabric material include: processing into personal equipment such as cut-resistant vests and police cut-resistant clothing of various specifications and styles, as well as industrial protection fields such as cut-resistant gloves, cut-resistant aprons, and logging chainsaw pants.

[0015] The beneficial effects of this invention are: 1. High-performance fiber filament bundles are impregnated with interface-modified resin using an online impregnation device, forming a resin protective film on the inside and surface of the yarn. This adhesively cures the monofilaments to form a composite yarn, improving the overall yarn's coverage and antifibrillation capabilities. This process solves the problems of monofilament displacement, dispersion, and breakage that easily occur in filament bundles during high-speed knitting, effectively addressing the issues of "needle snag" and "broken needles."

[0016] 2. The production process of the integral continuous high-performance puncture- and cut-resistant flexible composite fabric abandons the traditional composite fabric process of first weaving the original yarn and then performing finishing processes such as impregnation, coating, or lamination on the entire fabric. Instead, it adopts a process of first impregnating high-performance fibers to prepare composite yarns, and then weaving them. This not only solves the problem of severe wear on the yarn guide holes, needle hooks, and sinkers during high-speed operation, but also reduces monofilament breakage and lint accumulation during friction with machine metal parts. Furthermore, the resin protective film on the surface of the high-performance fiber filament bundles extends the service life of machine parts and reduces static electricity buildup and fiber adhesion to machine parts. At the same time, the composite fabric prepared by this process still maintains its breathability and softness.

[0017] 3. After being squeezed and shaped by multiple tension guides with circular central cavities, the high-performance composite yarn forms a quasi-circular cross-section, avoiding twisting and turning points and loop separation during knitting.

[0018] 4. The non-uniform diameter crimping mechanism is adopted, which solves the crimping phenomenon caused by edge stress of the fabric by taking into account the characteristics of high-performance fibers such as low breaking elongation, extremely high strength and high modulus. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the process flow of the present invention; Figure 2 This is a schematic diagram of the online impregnation device of the present invention; Figure 3 This is a schematic diagram of the elastic compression sheet of the present invention; Figure 4 This is a schematic diagram of the tension guide structure of the present invention.

[0020] In the picture: 1. Impregnation tank; 2. Elastic pressure plate; 3. Circulating spray device; 4. Unwinding guide roller; 5. Spreading unit; 6. Exit guide roller; 7. Guide wheel. Detailed Implementation

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0022] Example 1: Refer to Appendix Figures 1-4 This embodiment provides a flexible knitted cut-resistant composite fabric with an areal density of 600 g / m², which is knitted after continuous impregnation with resin liquid and curing, achieving excellent cut-resistant performance, flexibility and breathability, including the following steps: Para-aramid filaments with a linear density of 800D (breaking strength approximately 22.5 cN / dtex) were selected. An online filament spreading device was activated, using a set of Teflon-coated spreading rollers to physically flatten the aramid filament bundle without tension. The spread filament bundle was a thin ribbon, with its width increased from approximately 0.45 mm to 2.5 mm ± 0.2 mm, and the single-filament layer thickness was controlled to within 5 layers.

[0023] The flattened aramid ribbon filaments are fed into an online impregnation device. The interface-modifying resin is a polycarbonate-type aliphatic waterborne polyurethane resin solution (35% solid content) with a viscosity of 65 mPa·s. The impregnation device is equipped with a pair of 50 mm long elastic pressure plates 2 positioned opposite each other. The initial gap between the two pressure plates is adjusted to 0.35 mm (approximately 0.8 times the original fiber diameter), and the effective impregnation time is 5 seconds. The pressure plates apply a constant elastic pressure (approximately 2.5 N / cm), and the centripetal pressure generated by the extrusion allows the resin solution to completely penetrate into the gaps between the aramid monofilaments.

[0024] After impregnation, the aramid yarn enters the primary drying tunnel through the winding roller and undergoes transient pre-curing at 90°C for 20 seconds. The polyurethane resin liquid is pre-cured inside and on the surface of the aramid filament bundle, causing the resin to enter a viscoelastic state.

[0025] The pre-cured aramid composite yarn is sequentially passed through a shaping assembly of four tension guides with circular central cavities. The diameters of the central cavities of the tension guides are 1.2 mm, 0.8 mm, 0.6 mm, and 0.5 mm, respectively. The yarn is physically compressed and shaped using multi-axial orthogonal tension. After multiple stages of shaping, the pre-cured yarn is reshaped from a strip into a quasi-circular structure (see attached diagram). Figure 3 Microscopic observation revealed that the ratio of its major axis to minor axis was within the range of 1.2:1.0.

[0026] The pre-cured aramid composite yarn after shaping is sent into a secondary drying tunnel, where the curing temperature is 145℃ and the curing time is 45s to obtain the cured aramid composite yarn.

[0027] The cured aramid composite yarn is fed to an 11-needle circular knitting machine through a PVC yarn guide tube coated with diamond-like carbon, and wound on a yarn storage mechanism to establish tension buffer reserves before knitting. The loom is then started to knit, producing a preliminary composite fabric. During the winding process, a parabolic arc-shaped fabric roller is used, with the diameter of the middle section being 2mm larger than that of the ends. During weaving, the yarn exhibits excellent loop conformity at the needle hooks, with a breakage rate of 0 times / 1000 meters, and the fabric surface has clear loops, no horizontal stripes, and no overturning defects.

[0028] The initial composite fabric was treated with a soaping solution containing 5 g / L nonionic surfactant and 1.5 g / L sodium pyrophosphate at 60°C for 15 min to remove oil and surface liquid from the aramid composite fabric process. The soaped composite fabric was then fed into a hot roller setter at 90°C and a speed of 5 m / min to finally prepare the set cut-resistant composite fabric.

[0029] The prepared and shaped cut-resistant composite fabric can be used to process and manufacture flexible cut-resistant vests, stab-resistant vests, cut-resistant gloves, cut-resistant aprons, fencing uniforms, and other personal protective equipment. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), the single-layer cut-resistant composite fabric achieved a Class D rating using a TDM-100 cut resistance performance tester. A four-layer aramid composite fabric achieved Class A 24 Joule energy non-penetration according to GA68-2024 "Police Stab-Resistant Vests" standard. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 85 mm / s. These tests demonstrate that the woven cut-resistant composite fabric possesses both excellent cut-resistant performance and good air permeability.

[0030] The process is implemented using other aramid fiber specifications and parameters as follows:

[0031] The example uses a single-layer cut-resistant composite fabric made of 400D linear density aramid fiber. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade C. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 128 mm / s.

[0032] The example uses a single-layer cut-resistant composite fabric made of 600D linear density aramid fiber. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade C. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 106 mm / s.

[0033] The example uses a single-layer cut-resistant composite fabric made of aramid fiber with a linear density of 1600D. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade D. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 68 mm / s.

[0034] Reference Appendix Figures 2-3 The online impregnation device includes an impregnation tank 1 filled with an interfacial adhesion medium. An interfacial discharge port is located on one side of the impregnation tank 1 to discharge excess interfacial adhesion medium. Elastic pressure plates 2 are symmetrically arranged inside the impregnation tank 1, with a temporary adhesion zone between two opposing elastic pressure plates 2. A circulating spraying device 3 is also installed in the impregnation tank 1 above the two elastic pressure plates 2. The circulating spraying device 3 pumps in the interfacial adhesion medium through an external pipeline and sprays the interfacial adhesion medium onto the front section between the two elastic pressure plates 2. An unwinding guide roller 4 and a yarn unwinding unit 5 are symmetrically arranged on one side of the impregnation tank 1. An outlet guide roller 6 is provided on the other side of the tank 1, and a guide wheel 7 is also provided between the two elastic pressure plates 2. The guide wheel is installed on the inner wall of the impregnation tank 1. After the high-performance fiber filament bundle passes through the unwinding guide roller 4 and the unwinding unit 5, it is squeezed by the elastic pressure plates 2 which are arranged opposite each other. After being guided by the guide wheel 7, it is pulled out from the outlet guide roller 6. The elastic pressure plate 2 squeezes the filament bundle, and at the same time, the circulating spraying device 3 sprays the interface adhesion medium onto it. Then the filament bundle is impregnated by the interface adhesion medium again through the guide wheel 7. When it moves outward, the excess interface adhesion medium is squeezed out by the two elastic pressure plates 2.

[0035] Example 2: Refer to Appendix Figures 1-4 This embodiment provides a flexible knitted cut-resistant composite fabric with an areal density of 450 g / m², which is knitted after continuous impregnation with resin liquid and curing, achieving excellent cut-resistant performance, flexibility and breathability, including the following steps: Ultra-high molecular weight polyethylene (UHMWPE) filaments with a linear density of 400D (breaking strength approximately 32cN / dtex) were selected. An online filament spreading device was activated, using a set of Teflon-coated spreading rollers to flatten and widen the UHMWPE filament bundle. After spreading, the thickness of the filament bundle was reduced to 2-3 layers of monofilament diameter, and the width was expanded from approximately 0.25mm to 1.2mm ± 0.1mm to eliminate voids within the fiber bundle.

[0036] The flattened UHMWPE ribbon filaments are fed into an online impregnation device. The interface-modified resin is a modified polyether-type waterborne polyurethane resin solution with a low surface tension viscosity of 45 mPa·s. The impregnation device is equipped with a pair of elastic pressure plates 2, each 40 mm in length, positioned opposite each other. The initial gap between the two pressure plates is adjusted to 0.2 mm (approximately 0.8 times the original fiber diameter), and the effective impregnation time is 6 seconds. A constant elastic pressure (approximately 2.0 N / cm) is applied by the pressure plates, and the centripetal pressure generated by the extrusion allows the resin solution to completely penetrate into the gaps between the UHMWPE monofilaments.

[0037] After impregnation, the UHMWPE yarn enters the primary drying tunnel through a winding roller and is pre-cured at 75°C for 30 seconds. The polyurethane resin liquid is pre-cured inside and on the surface of the UHMWPE filament bundle, allowing the resin to enter a viscoelastic state.

[0038] The pre-cured UHMWPE composite yarn is sequentially passed through a shaping assembly of five tension guides with circular central cavities. The diameters of the central cavities in the tension guides are 1.5mm, 1.1mm, 0.8mm, 0.5mm, and 0.35mm, respectively. The yarn is physically extruded and shaped using multi-axial orthogonal tension. After multiple stages of shaping, the pre-cured yarn is reshaped from a strip into a quasi-circular structure. Testing shows that the ratio of its major axis to minor axis is within 1.3:1.0, and the gaps between the monofilaments are completely filled with resin.

[0039] The pre-cured UHMWPE composite yarn after shaping is sent into a secondary drying tunnel, where the curing temperature is 105℃ and the curing time is 20s, to obtain the cured UHMWPE composite yarn, ensuring that the composite yarn has excellent geometric stability during the knitting process.

[0040] The cured UHMWPE composite yarn is fed to a 15-gauge circular knitting machine through a PVC yarn guide tube coated with diamond-like carbon, and wound onto a yarn storage mechanism to establish tension buffer reserves before knitting. The loom is then started to knit, producing a preliminary composite fabric. Parabolic arc-shaped fabric rollers are used during winding, with the diameter of the middle section being 1.5 mm larger than that of the ends. During weaving, the rounded yarn cross-section and the resin protective film on the surface effectively eliminate the common UHMWPE phenomena of "needle breakage" and "slippage," improving weaving efficiency by more than 40%.

[0041] The initial composite fabric was treated with a soaping solution containing 2 g / L polyoxyethylene ether at 45°C for 20 min to remove oil and surface liquid from the UHMWPE composite fabric process. The soaped composite fabric was then fed into a hot roller setter at 70°C at a speed of 4 m / min to finally prepare the cut-resistant composite fabric. Testing showed that the fabric surface was clean, free of oil drips and yellow spots, and the resin matrix retention rate was ≥95%.

[0042] The prepared and shaped cut-resistant composite fabric can be used to process and manufacture flexible cut-resistant vests, stab-resistant vests, cut-resistant gloves, cut-resistant aprons, fencing uniforms, and other personal protective equipment. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), the single-layer cut-resistant composite fabric achieved a Class C rating when tested using a TDM-100 cut resistance performance tester. A 6-layer UHMWPE composite fabric achieved Class A 24 Joule energy non-penetration according to GA68-2024 "Police Stab-Resistant Vests" standard. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 120 mm / s. These tests demonstrate that the woven cut-resistant composite fabric possesses both excellent cut-resistant performance and good air permeability.

[0043] The following process is implemented using other UHMWPE specifications and parameters:

[0044] The example uses a single-layer cut-resistant composite fabric made of 200D linear density UHMWPE fiber. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade B. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 184 mm / s.

[0045] The example uses a single-layer cut-resistant composite fabric made of 800D linear density UHMWPE fiber. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade C. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 102 mm / s.

[0046] The example uses a single-layer cut-resistant composite fabric made of 1600D linear density UHMWPE fiber. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade C. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 72 mm / s.

[0047] Example 3: Refer to Appendix Figures 1-4 This embodiment provides a flexible knitted cut-resistant composite fabric with an areal density of 550 g / m², which is knitted after continuous impregnation with resin liquid and curing, achieving excellent cut-resistant performance, flexibility and breathability, including the following steps: Polyimide (PI) filaments with a linear density of 500D (breaking strength approximately 25 cN / dtex) were selected. An online filament spreading device was activated, using a set of Teflon-coated spreading rollers to physically flatten the PI filament bundle without tension. The spread filament bundle was a thin ribbon, with its width increased from approximately 0.35 mm to 2 mm ± 0.15 mm, and the single-filament layer thickness was controlled to within 5 layers.

[0048] The flattened PI ribbon filaments enter the online impregnation device. The interface modification resin is a high-temperature resistant polycarbonate-type waterborne polyurethane resin liquid with a viscosity of 75 mPa·s, and 2% silane coupling agent is added to enhance interfacial polarity. The impregnation device is equipped with a pair of elastic pressure plates 2 with a length of 60 mm arranged opposite each other. The initial gap between the two pressure plates is adjusted to 0.3 mm (approximately 0.8 times the original diameter of the fiber), and the effective impregnation time is 4 seconds. The pressure plates apply a constant elastic pressure (approximately 2.5 N / cm), and the centripetal pressure generated by the extrusion makes the resin liquid completely penetrate into the dumbbell-shaped grooves of the PI fiber monofilament, forming a tight "mortise and tenon" physical riveting fixing structure.

[0049] After impregnation, the PI yarn enters the primary drying tunnel through the winding roller and undergoes transient pre-curing at 100°C for 15 seconds. The polyurethane resin liquid is pre-cured inside and on the surface of the PI filament bundle, causing the resin to enter a viscoelastic state.

[0050] The pre-cured PI composite yarn is sequentially passed through five tension guide shaping groups with gradually decreasing diameters of circular central cavities. The diameters of the central cavities of the tension guides are 1.2 mm, 1.0 mm, 0.8 mm, 0.6 mm, and 0.45 mm, respectively. The yarn is physically extruded and shaped using multi-axial orthogonal tension. After multiple stages of shaping, the pre-cured yarn is reshaped from a strip shape into a quasi-circular structure. Microscopic observation shows that the ratio of its major axis to minor axis is within the range of 1.1:1.0.

[0051] The pre-cured PI composite yarn after shaping is sent into a secondary drying tunnel, where the curing temperature is 160℃ and the curing time is 35s to obtain the cured PI composite yarn.

[0052] The cured PI composite yarn is fed to a 15-gauge circular knitting machine through a PVC yarn guide tube coated with diamond-like carbon, and wound onto a yarn storage mechanism to establish tension buffer reserves before knitting. The loom is then started to knit, creating a preliminary composite fabric. During the winding process, a parabolic arc-shaped fabric roller is used, with the diameter of the middle section being 1.5 mm larger than that of the ends. Because the PI fiber surface is stabilized after resin treatment, the coefficient of friction remains constant during weaving, effectively avoiding the common "linting" phenomenon of PI fibers, resulting in a fabric surface with extremely high smoothness and a metallic texture.

[0053] The initial composite fabric was treated with a soaping solution containing 5 g / L of polar penetrant at 85°C for 20 minutes to remove oil and surface residue from the PI composite fabrication process. The soaped composite fabric was then fed into a hot roller setter at 100°C at a speed of 6 m / min to finally prepare the cut-resistant composite fabric. Because the resin was deeply locked within the fiber grooves at high temperature, the resin retention rate after soaping was ≥97%, and the fabric retained the inherent flame-retardant properties of the PI fibers.

[0054] The prepared cut-resistant composite fabric can be used to manufacture flexible cut-resistant vests, stab-resistant and flame-retardant clothing, cut-resistant gloves, cut-resistant aprons, fencing uniforms, and other personal protective equipment. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), the single-layer cut-resistant composite fabric achieved a Class D rating using a TDM-100 cut resistance performance tester. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 110 mm / s. These tests demonstrate that the woven cut-resistant composite fabric possesses both excellent cut resistance and good air permeability. Furthermore, the polyimide fiber has a melting point above 500 degrees Celsius and exhibits good long-term flame-retardant properties.

[0055] The following process is implemented using other PI fiber specifications:

[0056] The example uses a single-layer cut-resistant composite fabric made of 200D linear density PI fiber. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade B. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 178 mm / s.

[0057] The example uses a single-layer cut-resistant composite fabric made of 1000D linear density PI fiber. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade D. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 102 mm / s.

[0058] The example uses a single-layer cut-resistant composite fabric made of 1600D linear density UHMWPE fiber. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), it achieved Grade C. According to GB / T5453-2025 "Textiles - Determination of Air Permeability of Fabrics", the air permeability reached 83 mm / s.

[0059] Example 4: A product of high-performance cut-resistant composite fabric, which is made by continuous knitting process of high-performance cut-resistant composite fabric. The application fields of cut-resistant composite fabric material include: processing into personal equipment such as cut-resistant vests and police cut-resistant clothing of various specifications and styles, and also applied in industrial protection fields such as cut-resistant gloves, cut-resistant aprons, and logging chainsaw pants.

[0060] Comparative Example 1 (Direct dry weaving + finishing fabric coating) Implementation process steps: Raw material preparation: The same 800D para-aramid filament as in Example 1 of this invention is used. No pre-spreading, impregnation, or shaping treatment is performed.

[0061] Direct dry weaving: The raw aramid filament is fed into a 14G double-sided circular knitting machine through a conventional yarn guiding device.

[0062] Phenomenon record: Due to the flat, ribbon-like cross-section of the fiber (shape ratio of approximately 5:1), it frequently flips when entering the needle hook, resulting in violent fluctuations in tension.

[0063] Phenomenon Record: Due to the extremely high surface modulus of the fiber and the lack of resin protection, the fiber and metal needle hooks generate strong friction, which easily leads to static electricity during the manufacturing process. The circular knitting machine frequently stops, and the yarn breaks approximately 30-50 times per 1000 meters. After one hour of weaving, a large amount of aramid debris and fuzz accumulates in the triangular disc and sinker areas, and the knitting needles and sinkers show severe wear.

[0064] Post-treatment of the initial fabric: The woven dry knitted fabric is immersed in a polycarbonate-based waterborne polyurethane (PUD) bath of the same concentration for "two dips and two nips".

[0065] Drying and setting: Stretching and drying are carried out at 145℃ to cure the resin on the fabric surface.

[0066] Results presented: Due to the tight structure of the knitted loops, the resin can only coat the fabric surface and the loop interlacing points, unable to penetrate into the fiber bundle, resulting in poor consistency in cut resistance. According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), the single-layer cut-resistant composite fabric was tested using a TDM-100 cut resistance performance tester and achieved Grade B. Aramid fabric with 7 layers of this surface coating can achieve Class A 24 Joule energy non-penetration according to GA68-2024 "Police Stab-Resistant Vest" standard.

[0067] According to GB / T5453-2025 "Determination of Air Permeability of Textile Fabrics", the air permeability was practically zero, ranging from 0-10 mm / s. This is because the resin sealed the gaps between the loops and formed a resin film on the fabric surface, making it difficult for gas to pass through during testing. Furthermore, the fabric felt stiff and lacked the stretch of knitted fabrics.

[0068] Comparative Example 2 (twist pretreatment + dry weaving + finishing fabric coating) Implementation process steps: Mechanical twisting: The same 800D para-aramid filament as in Embodiment 1 of this invention is selected and twisted in the Z direction on a twisting machine. The twist is set to 200-400T / m (the number of twists is set according to 800D). The fiber is gathered into a cylindrical shape by mechanical twisting force.

[0069] Steaming and setting: The twisted yarn is placed in a steaming box and set using high-temperature steam to prevent untwisting.

[0070] Knitting: The twisted and set yarn is fed into a 14G double-sided circular knitting machine for weaving. Initial processing: The woven knitted fabric is immersed in a polycarbonate-based waterborne polyurethane (PUD) bath of the same concentration for "two dips and two nips".

[0071] Drying and setting: Stretching and drying are carried out at 145℃ to cure the resin on the fabric surface.

[0072] Post-treatment: Perform a regular soap wash to remove the twisted oils.

[0073] Observation: Twisted yarn reduces tumbling and is significantly easier to weave than dry weaving. Yarn breakage occurs approximately 10-20 times per 1000 meters. One hour after weaving, a small amount of aramid debris and fuzz accumulates in the triangular disc and sinker areas.

[0074] Results presented: While twisting high-performance fibers facilitates weaving, the lack of physical isolation from the interfacial resin film means that the exposed "hard" fibers continue to cause wear on the needle hooks, resulting in a shorter equipment lifespan and more severe wear on the sinker. Furthermore, after twisting, the resin struggles to penetrate the fibers, only coating the fabric surface and loop interlacing points, forming a resin film on the fabric surface.

[0075] According to the national standard GB24541-2022 "Hand Protection - Mechanical Hazard Protective Gloves" 6.3 Cut Resistance (Straight Knife Test Method), the single-layer cut-resistant composite fabric was tested using a TDM-100 cut resistance performance tester and achieved Grade B. A 7-layer aramid fabric with this surface coating can achieve Class A 24 Joule energy non-penetration according to the GA68-2024 "Police Stab-Resistant Vest" standard.

[0076] According to GB / T5453-2025 "Determination of Air Permeability of Textile Fabrics", the air permeability was still virtually nonexistent, at 0-10 mm / s. This is because the resin seals the gaps between the loops and forms a resin film on the fabric surface, making it difficult for gas to pass through during testing. Simultaneously, the fabric feels stiffer and loses its elasticity characteristic of knitted fabrics.

[0077] Comparative Example 3 (Pre-cured yarn impregnation + Unshaped yarn + Knitted fabrication) Implementation process steps: Raw material preparation and yarn spreading: The same 800D para-aramid filament as in Example 1 of this invention was selected. The same spreading rollers were used to physically flatten the filament, expanding the fiber bundle width to approximately 2.5 mm, forming a ribbon shape.

[0078] Online impregnation and pre-curing: Impregnation is performed using a water-based polyurethane resin liquid with the same viscosity of 65 mPa⋅s, followed by primary pre-curing at 90°C.

[0079] Skip all gradient shaping guides to maintain the original flat ribbon structure of the impregnated fiber bundle (cross-sectional shape ratio of approximately 5:1) and directly perform secondary curing and shaping.

[0080] Knitting: This flat, ribbon-like composite yarn is fed into a 14G double-sided circular knitting machine through a yarn guide tube.

[0081] Soap washing and setting: The same soap washing and setting process is used.

[0082] Phenomenon Record: Due to the flat shape of the yarn, it frequently undergoes random rotation and flipping when passing through the yarn guide and entering the needle hook, causing the circular knitting machine to stop occasionally, with approximately 10-20 yarn breaks per 1000 meters. The bending resistance differs greatly between the flat yarn entering the needle hook from the "side" (narrow edge) and the "front" (wide edge), resulting in violent high-frequency pulse-like fluctuations in the yarn supply tension.

[0083] Results analysis: Severe fabric defects: Due to the tumbling of flat yarns, numerous irregular "twist points" and "missed stitches" appear on the fabric surface. The loop sizes are extremely uneven, and the fabric surface exhibits obvious longitudinal streaks and transverse stress lines.

[0084] The breakage rate is significantly increased: the edges of flat yarns are easily caught on the edges of needles or sinkers during high-speed movement. Because they have not undergone quasi-rounding shaping, the exposed area of ​​the monofilament edges is large, and due to the influence of shear force, the breakage rate is more than 20 times higher than that of the present invention.

[0085] Poor puncture resistance consistency: Tests show that when the blade tip just pierces the side of the flattened yarn after it has been turned over, the fibers easily slip to both sides. Experiments have shown that the puncture resistance performance fluctuation value (CV%) of fabrics that have not undergone shaping is as high as 15% or more, and their cut and puncture resistance performance is unstable.

[0086] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A continuous knitting process for a high-performance cut-resistant composite fabric, characterized in that, Includes the following steps: Online impregnation and monofilament-level interface construction: A transient expansion process is used to actively expand the high-performance fiber bundle into an ultra-thin ribbon-like form with a monofilament layer thickness of ≤5 layers. The passing filament bundle is compressed using relatively positioned elastic pressure plates, while simultaneously impregnating with an interface adhesion medium. Pre-curing and preliminary shaping: The impregnated filament bundle enters the first-stage drying tunnel for pre-curing at a temperature controlled at 70-100℃ for 10-30 seconds. This allows the resin to form a viscoelastic transient protective film on the fiber surface, creating a stable mechanical bonding structure between the resin and the yarn, thus preparing a pre-cured composite yarn. Multi-stage gradient physical shaping: The pre-cured composite yarn continuously passes through 2-6 tension guides with circular central cavities. The cavity size of the tension guides decreases gradually along the running direction. Multi-axial orthogonal tension is used to physically compress and shape the yarn, forcibly constraining its cross-sectional shape ratio within a quasi-circular range of 1.0-1.5:1.0, eliminating the flat, ribbon-like shape of the original high-performance fibers. Structure; Secondary curing and setting: The quasi-circular composite yarn after shaping enters the second-stage drying tunnel for secondary curing. The curing temperature is controlled at 100-160℃ for 10-60s to lock the geometric shape of the fiber bundles and obtain a high-performance composite yarn after curing; Constant tension balancing weaving: The obtained high-performance composite yarn after curing is transported to the yarn storage mechanism of the knitting equipment through a closed yarn guide tube for buffer winding of a predetermined number of turns. The knitting machine is started for weaving. During the winding process, the tension balance of the fabric is adjusted by a non-uniform diameter take-up mechanism to obtain the initial composite fabric; Selective soaping and setting: The initial fabric is treated with a soaping mixture containing emulsifiers and oxidants to selectively remove the machine oil and surface residue generated during the weaving process, while retaining the interfacial resin film inside the fiber and on the surface; After selective soaping, the resin matrix retention rate between the fibers of the composite fabric is ≥90%. After drying and setting, a puncture-resistant and cut-resistant composite fabric with good air permeability and multi-directional extensibility is obtained.

2. The continuous knitting process for the high-performance cut-resistant composite fabric according to claim 1, characterized in that: The interfacial adhesion medium is a modified water-washable polyurethane resin with a viscosity of 10-300 mPa·s and an effective residence time of 1-20 s.

3. The continuous knitting process for the high-performance cut-resistant composite fabric according to claim 1 or 2, characterized in that: The high-performance fibers include ultra-high molecular weight polyethylene fibers, aramid fibers, and polyimide fibers used for weaving yarns, with a fiber strength greater than 20 cn / dtex and a specific modulus greater than 400 cn / dtex.

4. The continuous knitting process for the high-performance cut-resistant composite fabric according to claim 3, characterized in that: The elastic pressure plate is a high-flatness elastic pressure plate with a length of 20-100mm. The initial gap d between two oppositely arranged elastic pressure plates is set to 0.5-1.5 times the original diameter D of the high-performance fiber bundle.

5. The continuous knitting process for the high-performance cut-resistant composite fabric according to claim 1, characterized in that: The transient expansion process includes: passing high-performance fiber bundles sequentially through a set of expansion rollers with Teflon surfaces, and using the mechanical friction or ultrasonic vibration of the expansion rollers to unfold the original cylindrical or rope-shaped filament bundles into a ribbon shape; and then reshaping the pre-cured composite yarn into a quasi-circular shape through multi-level gradient physical shaping.

6. The continuous knitting process for the high-performance cut-resistant composite fabric according to claim 1, characterized in that: During the online impregnation process, a constant pressure is applied by an elastic pressing plate to keep the actual working gap at 0.8-1.2 times the fiber bundle diameter.

7. The continuous knitting process for the high-performance cut-resistant composite fabric according to claim 1, characterized in that: The cavity size of the tension guide gradually decreases from 200% to 100% of the fiber fineness along the running direction; the cross-sectional shape ratio is the ratio of the major axis to the minor axis.

8. The continuous knitting process for the high-performance cut-resistant composite fabric according to claim 1, characterized in that: The non-uniform diameter winding mechanism is designed with an arc-shaped roller with a slightly larger diameter in the middle and a gradually decreasing diameter at both ends. The diameter of the middle section is 0.05-3.0 mm larger than the diameters at both ends.

9. The continuous knitting process for the high-performance cut-resistant composite fabric according to claim 1, characterized in that: The drying and setting process involves setting the soaped composite fabric with hot rollers at a temperature of 70-100℃ and a speed of 5-10 m / min.

10. A product of a high-performance cut-resistant composite fabric, manufactured using the continuous knitting process of the high-performance cut-resistant composite fabric according to any one of claims 1-9, characterized in that: Applications of stab-proof and cut-proof composite fabric materials include: processing various specifications and styles of stab-proof vests, police stab-proof clothing and other personal equipment, as well as industrial protection applications such as cut-proof gloves, cut-proof aprons, and logging chainsaw pants.

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