High-strength needle-punched composite nonwoven fabric and preparation method thereof

Abstract

The invention relates to the technical field of non-woven fabric preparation, specifically to a high-strength needle-punched composite non-woven fabric and a preparation method, comprising a non-woven fabric needle-punched fiber web layer, a water-absorbing interlayer is arranged on the outside of the non-woven fabric needle-punched fiber web layer, and a surface film layer is arranged on the outside of the water-absorbing interlayer, and the beneficial effect is: by arranging a hot-melt fiber transition layer between the non-woven fabric needle-punched fiber web layer and the water-absorbing interlayer, and between the water-absorbing interlayer and the surface film layer, the water absorption and strength of the non-woven fabric are improved, and the preparation method is improved, three times of needle-punching are used to form physical cross-links between fibers, the strength and stability of the fiber web are enhanced, and the strength and density of the composite non-woven fabric are improved, and at the same time, a hot pressing equipment component and a transmission equipment component cooperate to hot-press the composite non-woven fabric after three needle-punching, and the hot-melt fiber transition layer is melted by hot pressing to bond the non-woven fabric needle-punched fiber web layer, the water-absorbing interlayer, and the surface film layer layer by layer to form a whole, thereby enhancing the integrity and stability of the structure.

Description

Technical Field

[0001] The invention belongs to the technical field of non-woven fabric preparation, and specifically relates to a high-strength needle-punched composite non-woven fabric and a preparation method thereof. Background Art

[0002] High-strength needle-punched composite non-woven fabric is a high-performance non-woven material made by a special process, which has high strength, durability and good composite properties. It is usually made of a variety of fiber materials, such as polyester, polypropylene, viscose fiber, etc., processed by needle punching process, and sometimes combined with other materials or lamination technology to enhance specific properties. Water-absorbent non-woven fabric is a kind of non-woven fabric, which is widely used in clothing materials, filter materials, wastewater treatment, sanitary products, medical supplies, chemical products and other fields. Traditional water-absorbent non-woven fabrics are mostly directly combined by multiple layers of non-woven fabrics. Since non-woven fabrics are mostly composed of short fibers and filaments arranged in an undirectional manner, the water-absorbent non-woven fabrics formed by them will absorb water and expand. The interaction force between the short fibers and filaments is sharply weakened, resulting in the loss of tensile ductility and the disadvantage of easy breakage due to stretching.

[0003] The existing Chinese patent document with publication number CN106042558A proposes a medical needle-punched non-woven fabric, including an outermost PTFE film layer, an intermediate water-absorbing material layer and an inner non-woven fabric substrate to solve the above problems. However, the PTFE film layer, the intermediate water-absorbing material layer and the inner non-woven fabric may separate or fall off after absorbing water and swelling.

[0004] Therefore, the present invention proposes a high-strength needle-punched composite non-woven fabric and a preparation method to solve the problem in the prior art that the non-woven fabric may separate or fall off between layers after absorbing water and swelling. Multiple needle-punching methods are adopted, hot-melt fibers are added layer by layer, and finally hot-pressed into one-piece molding so that the layers are bonded into a whole, thereby improving the strength and stability of the non-woven fabric. Summary of the invention

[0005] In view of the shortcomings of the prior art, the object of the present invention is to provide a high-strength needle-punched composite non-woven fabric and a preparation method to solve the problems raised in the above background technology.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a high-strength needle-punched composite non-woven fabric, comprising a non-woven needle-punched fiber web layer, a water-absorbing interlayer is arranged on the outside of the non-woven needle-punched fiber web layer, a surface film layer is arranged on the outside of the water-absorbing interlayer, and a hot-melt fiber transition layer is arranged on the surface of the non-woven needle-punched fiber web layer and the water-absorbing interlayer.

[0007] A method for preparing a high-strength needle-punched composite non-woven fabric comprises the following steps:

[0008] Step 1: Raw material preparation: Select appropriate fiber raw materials according to the performance requirements of the final product and pre-treat the fibers;

[0009] Step 2: Fiber web formation: the processed fibers are evenly fed into the web forming machine through an automatic feeding system, and a uniform fiber web layer is formed through air combing;

[0010] Step 3: Needle Punch Reinforcement: The web is fed into a needle punching machine, and the high-speed needles penetrate the web to form physical cross-links between the fibers.

[0011] Step 4, adding an intermediate layer: After pre-needling the fiber web, add a hot-melt fiber transition layer, and continue with the main needling. After the main needling, add a water-absorbing intermediate layer and a hot-melt fiber transition layer in sequence, and then continue with the post-needling. Finally, lay a surface film layer on the surface layer;

[0012] Step 5: Hot-melt compounding: A specially designed hot-pressing device is used to hot-press the reset non-woven fabric after needle punching. The hot-melt fiber transition layer bonds the multiple layers of materials together during the hot-pressing process.

[0013] Step 6. Post-processing: Stabilize the fiber structure through low-temperature ironing, and carry out coating, printing, and anti-static treatment according to market demand. Finally, conduct quality inspection, cut and wind the finished needle-punched composite non-woven fabric according to specification requirements, and prepare for packaging and transportation.

[0014] Preferably, the step one also includes pretreatment of the fibers by loosening, mixing and removing impurities, the step three includes three stages of pre-needling, main needling and post-needling, and the hot pressing device proposed in the step five includes a hot pressing equipment assembly, and a transmission equipment assembly is arranged below the hot pressing equipment assembly.

[0015] Preferably, the hot pressing equipment assembly includes a mounting frame, and heat-insulating fixed round heads are symmetrically fixedly installed on the inner walls of both sides of the mounting frame, an inner heat-conducting ring and a hot air exchange ring are fixedly installed between two groups of the heat-insulating fixed round heads, the hot air exchange ring is arranged on the inner side of the inner heat-conducting ring, and a hollow hot pressing roller is rotatably installed on the outer surface of the inner heat-conducting ring, an electric heating component is fixedly installed inside one group of the heat-insulating fixed round heads, the electric heating component is arranged inside the hot air exchange ring, and a temperature control device is arranged outside the electric heating component.

[0016] Preferably, ventilation grooves are evenly opened on the side walls of the hot air exchange circle, a notch is provided below the inner heat conductive circle, a closed partition is fixedly installed above the notch of the inner heat conductive circle, and the upper end of the closed partition is fixedly connected to the outer surface of the hot air exchange circle.

[0017] Preferably, a movable closing plate is provided at the notch of the inner heat conduction ring, an arc-shaped wind guide plate is symmetrically fixedly installed in the middle of the movable closing plate, a connecting plate is symmetrically provided above the movable closing plate, the connecting plate is fixedly installed on the inner surface of the hot air exchange ring, an elastic gasket is fixedly installed on the lower surface of the connecting plate, and the lower end of the elastic gasket is fixedly connected to the upper surface of the movable closing plate.

[0018] Preferably, heat dissipation grooves and hot air exhaust outlets are evenly arranged on the surface of the hollow hot pressing roller, and the heat dissipation grooves and the hot air exhaust outlets are staggered. A hot pressing plate is arranged on the outside of the heat dissipation grooves, and a short air duct compatible with the hot air exhaust outlet is fixedly installed on the outer surface of the hollow hot pressing roller. Limiting frames are evenly distributed on the inner side of the hollow hot pressing roller, and the limiting frames are fixedly installed on the inner surface of the hollow hot pressing roller.

[0019] Preferably, a movable push head is movably installed inside the limit frame, a spring is fixedly installed on one side surface of the movable push head, one end of the spring is fixedly connected to the inner surface of the hollow hot pressing roller, a connecting rod is symmetrically rotatably installed on the inner surface of the hot pressing sheet, and one end of the connecting rod is rotatably connected to the side surface of the movable push head.

[0020] Preferably, a fan is provided on one side of the mounting frame, an air filter cartridge is provided above the fan, the air filter cartridge is fixedly mounted on the side wall of the mounting frame, a disassembly cover is snap-fitted on one end of the air filter cartridge, an air filter is snap-fitted inside the air filter cartridge, an output pipe of the fan passes through the inner wall of the other side of the air filter cartridge and extends into the air filter, a delivery pipe is fixedly mounted above the side wall of the air filter cartridge, an air inlet pipe is fixedly mounted on the upper end of the delivery pipe, the air inlet pipe is fixedly mounted inside a heat-insulating fixed round head, and the output pipe of the air inlet pipe passes through the inner wall of the mounting frame and extends between the inner heat-conducting ring and the hot air exchange ring.

[0021] Preferably, a motor is fixedly mounted on the side wall of the mounting frame, a driving gear is fixedly mounted on the output shaft of the motor, a rack is provided below the driving gear, the rack is fixedly mounted on the outside of one end of the hollow hot pressing roller by bolts, and the outer surface of the rack is meshed with the outer surface of the driving gear.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] By arranging a hot-melt fiber transition layer between the non-woven fabric needle-punched fiber web layer and the water-absorbing interlayer, and between the water-absorbing interlayer and the surface film layer, the water absorption and strength of the non-woven fabric are improved, and the preparation method is improved. Three needle-punchings are used to form physical cross-links between the fibers, enhance the strength and stability of the fiber web, and improve the strength and density of the composite non-woven fabric. At the same time, the hot pressing equipment component and the transmission equipment component cooperate to hot-press the composite non-woven fabric after three needle-punchings. The hot-melt fiber transition layer is melted by hot pressing to bond the non-woven fabric needle-punched fiber web layer, the water-absorbing interlayer, and the surface film layer layer by layer to form a whole, thereby enhancing the integrity and stability of the structure, and solving the problem in the prior art that the non-woven fabric may separate or fall off after absorbing water and swelling. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the composite nonwoven fabric of the present invention;

[0025] Figure 2 It is a schematic diagram of the layered structure of the composite nonwoven fabric of the present invention;

[0026] Figure 3 It is a schematic diagram of the structure of the hot pressing equipment component and the transmission equipment component of the present invention;

[0027] Figure 4 It is a structural schematic diagram of one side of the hot pressing equipment assembly of the present invention;

[0028] Figure 5 It is a structural schematic diagram of the other side of the hot pressing equipment assembly of the present invention;

[0029] Figure 6 It is a schematic diagram of the structure of the heat-insulating fixed round head and the hollow hot pressing roller of the present invention;

[0030] Figure 7 It is a schematic diagram of the internal structure of the heat-insulating and insulating fixed round head of the present invention;

[0031] Figure 8 It is a schematic diagram of the structure of the hollow hot pressing roller of the present invention;

[0032] Fig. 9 It is a schematic diagram of the cross-sectional structure of the inner heat-conducting ring and the hot air exchange ring of the present invention;

[0033] Fig.10 It is a schematic diagram of the internal structure of the inner heat conducting ring of the present invention when viewed from above;

[0034] Fig.11 It is a schematic diagram of the internal structure of the inner heat conducting ring of the present invention;

[0035] Fig.12 It is a schematic flow chart of the preparation method of the present invention.

[0036] In the figure: 1. Non-woven needle-punched fiber web layer; 2. Water-absorbing interlayer; 3. Surface film layer; 4. Heat-melting fiber transition layer; 5. Hot pressing equipment components; 51. Mounting frame; 52. Heat-insulating fixed round head; 521. Electric heating component; 522. Inner heat-conducting ring; 523. Hot air exchange ring; 5231. Ventilation slot; 524. Closed partition; 525. Movable closed plate; 5251. Arc-shaped wind guide plate; 526. Connecting plate; 5261. Elastic gasket; 53. Hollow hot pressing roller; 531 , heat sink; 532, hot pressing plate; 5321, connecting rod; 5322, elastic push plate; 5323, indentation groove; 533, hot air outlet; 534, short air duct; 535, limit frame; 5351, movable push head; 5352, spring; 54, fan; 55, air filter cartridge; 551, disassembly cover; 552, air filter; 553, delivery pipe; 554, air inlet pipe; 56, motor; 561, drive gear; 562, rack; 6, transmission equipment components. DETAILED DESCRIPTION

[0037] In order to make the purpose and technical solution of the present invention clearly and completely described, and the advantages more clearly understood, the embodiments of the present invention are further described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are part of the embodiments of the present invention, not all of them, and are only used to explain the embodiments of the present invention, and are not used to limit the embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Embodiment 1

[0038] See also Figures 1 to 2 The present invention provides a technical solution: a high-strength needle-punched composite non-woven fabric, comprising a non-woven needle-punched fiber web layer 1, a water-absorbing interlayer 2 is arranged on the outside of the non-woven needle-punched fiber web layer 1, a surface film layer 3 is arranged on the outside of the water-absorbing interlayer 2, and a hot-melt fiber transition layer 4 is arranged on the surface of the non-woven needle-punched fiber web layer 1 and the water-absorbing interlayer 2;

[0039] In this embodiment, the water-absorbing interlayer 2 is a highly absorbent resin with a high water absorption rate. After absorbing water, it forms a gel to lock in moisture and can maintain a low re-permeability even under pressure, thereby improving the water absorption of the composite non-woven fabric. The surface film layer 3 is a PVDF film with good chemical stability and weather resistance, good flexibility, and is easier to process and form. It is used to improve the tensile strength, tear strength and wear resistance of the composite non-woven fabric. The hot-melt fiber transition layer 4 is a polyester PET fiber with good strength, durability and dimensional stability. A hot-melt fiber transition layer 4 is provided between the non-woven needle-punched fiber mesh layer 1 and the water-absorbing interlayer 2, and between the water-absorbing interlayer 2 and the surface film layer 3. The hot-melt fiber transition layer 4 melts under heating conditions and solidifies after cooling, which can effectively combine different layers of materials tightly together to avoid interlayer separation or falling off during use, thereby improving the stability and durability of the overall structure and improving the strength of the composite non-woven fabric. Embodiment 2

[0040] See also Fig.12 On the basis of Example 1, in order to prepare a high-strength needle-punched composite non-woven fabric, this embodiment also proposes a method for preparing a high-strength needle-punched composite non-woven fabric, comprising the following steps: Step 1, raw material preparation: according to the performance requirements of the final product, select suitable fiber raw materials and pre-treat the fibers; Step 2, fiber web formation, the treated fibers are evenly fed into the web forming machine through an automatic feeding system, and a uniform fiber web layer is formed by air combing; Step 3, needle punching reinforcement: the web is fed into the needle punching machine, and the high-speed needles penetrate the web to form physical crosslinks between the fibers; Step 4, adding an intermediate layer: after the fiber web is pre-needled, a hot-melt fiber transition layer is added, and the main needling is continued. After the main needling, a water-absorbing intermediate layer and a hot-melt fiber transition layer are added in sequence Then continue with post-needling, and finally lay an additional surface film layer on the surface layer; Step 5, hot melt composite: a specially designed hot pressing device is used to hot press the reset non-woven fabric after needle punching, and the hot melt fiber transition layer bonds the multiple layers of materials together during the hot pressing process; Step 6, post-processing: the fiber structure is stabilized by low-temperature ironing, and coating, printing, and anti-static treatment are performed according to market demand, and finally quality inspection is performed, and the finished needle-punched composite non-woven fabric that passes the quality inspection is cut and wound according to specification requirements, ready for packaging and transportation; Step 1 also includes pre-treatment of fibers by opening, mixing, and removing impurities, and Step 3 includes three stages: pre-needling, main needling, and post-needling. The hot pressing device proposed in Step 5 includes a hot pressing equipment component 5, and a transmission equipment component 6 is arranged below the hot pressing equipment component 5;

[0041] In this embodiment, multiple needling processes combined with the addition of a hot-melt fiber transition layer 4 can significantly enhance the structural stability of the non-woven fabric. After the first needling of the hot-melt fiber transition layer 4, a preliminary fiber mesh structure is formed. The second needling further consolidates this structure and allows the hot-melt fiber transition layer 4 to be fully distributed on the non-woven needle-punched fiber mesh layer 1. The third needling strengthens the connection between the fibers again. The whole process greatly improves the mechanical strength and durability of the non-woven fabric. In addition, by adding the hot-melt fiber transition layer 4 before and after the water-absorbing interlayer 2, the water-absorbing interlayer 2 can be effectively fixed, so that it maintains a good morphological stability when it absorbs water and expands, avoiding stratification or displacement. Multiple needling and the alternating addition of the hot-melt fiber transition layer 4 ensure the uniform distribution and close fit between different material layers, reduce gaps, and improve the overall uniformity and quality consistency of the composite material. Embodiment 3

[0042] See also Figures 1 to 12 On the basis of the second embodiment, in order to make the non-woven fabric integrally hot-pressed, the present embodiment further proposes that the hot-pressing equipment assembly 5 comprises a mounting frame 51, and the inner walls of both sides of the mounting frame 51 are symmetrically fixedly mounted with heat-insulating fixed round heads 52, and an inner heat-conducting ring 522 and a hot air exchange ring 523 are fixedly mounted between the two sets of heat-insulating fixed round heads 52, and the hot air exchange ring 523 is arranged on the inner side of the inner heat-conducting ring 522, and a hollow hot-pressing roller 53 is rotatably mounted on the outer surface of the inner heat-conducting ring 522, and the inner side of a set of heat-insulating fixed round heads 52 is fixedly mounted with a hot air exchange ring 523, and the hot air exchange ring 523 is arranged on the inner side of the inner heat-conducting ring 522. An electric heating component 521 is fixedly installed on the part, and the electric heating component 521 is arranged inside the hot air exchange circle 523. A temperature control device is arranged outside the electric heating component 521. A motor 56 is fixedly installed on the upper side wall of the mounting frame 51. A driving gear 561 is fixedly installed on the output shaft of the motor 56. A rack 562 is arranged below the driving gear 561. The rack 562 is fixedly installed on the outer side of one end of the hollow hot pressing roller 53 by bolts, and the outer surface of the rack 562 is meshed with the outer surface of the driving gear 561.

[0043] In this embodiment, the mounting frame 51 serves to mount the heat-insulating fixed round head 52, and the heat-insulating fixed round head 52 serves to mount the hollow hot pressing roller 53. The transmission equipment component 6 transports the composite non-woven fabric after needle punching so that it passes under the hollow hot pressing roller 53. The electric heating component 521 works to heat, and the hot air exchange circle 523 and the inner heat conductive circle 522 gather and transfer heat to increase the temperature of the hollow hot pressing roller 53. The motor 56 works to drive the driving gear 561 to rotate, and the driving gear 561 drives the rack 562 to rotate, so that the hollow hot pressing roller 53 rotates as a whole, and the composite non-woven fabric passing under it is hot-pressed, so that the hot-melt fiber transition layer 4 melts and bonds to ensure uniform distribution and tight fit between different material layers. Embodiment 4

[0044] See also Figures 1 to 12 On the basis of the third embodiment, in order to make the hot pressing of the hollow hot pressing roller 53 more uniform, the present embodiment further proposes that the side wall of the hot air exchange circle 523 is evenly provided with ventilation grooves 5231, a notch is provided below the inner heat conductive circle 522, a closed partition 524 is fixedly installed above the notch of the inner heat conductive circle 522, the upper end of the closed partition 524 is fixedly connected to the outer surface of the hot air exchange circle 523, a movable closed plate 525 is provided at the notch of the inner heat conductive circle 522, an arc-shaped wind guide plate 5251 is symmetrically fixedly installed in the middle of the movable closed plate 525, and a connecting plate 526 is symmetrically provided above the movable closed plate 525, The connecting plate 526 is fixedly installed on the inner surface of the hot air exchange circle 523, and an elastic gasket 5261 is fixedly installed on the lower surface of the connecting plate 526. The lower end of the elastic gasket 5261 is fixedly connected to the upper surface of the movable closing plate 525. The surface of the hollow hot pressing roller 53 is evenly provided with heat dissipation grooves 531 and hot air outlets 533. The heat dissipation grooves 531 and the hot air outlets 533 are staggered. A hot pressing sheet 532 is arranged on the outer side of the heat dissipation grooves 531. A short air duct 534 adapted to the hot air outlet 533 is fixedly installed on the outer surface of the hollow hot pressing roller 53. The inner side of the hollow hot pressing roller 53 is evenly distributed with a limit frame 531. 35, the limit frame 535 is fixedly installed on the inner surface of the hollow hot pressing roller 53, and a movable push head 5351 is movably installed inside the limit frame 535, and a spring 5352 is fixedly installed on one side surface of the movable push head 5351, and one end of the spring 5352 is fixedly connected to the inner surface of the hollow hot pressing roller 53, and a connecting rod 5321 is symmetrically rotated on the inner surface of the hot pressing sheet 532, and one end of the connecting rod 5321 is rotatably connected to the side surface of the movable push head 5351. A fan 54 is arranged on one side of the mounting frame 51, and an air filter cartridge 55 is arranged above the fan 54. The air filter cartridge 55 is fixedly installed on On the side wall of the mounting frame 51, a disassembly cover 551 is mounted on one end of the air filter cartridge 55, an air filter screen 552 is mounted on the inside of the air filter cartridge 55, an output pipe of the fan 54 penetrates the inner wall of the other side of the air filter cartridge 55 and extends into the inside of the air filter screen 552, a delivery pipe 553 is fixedly mounted on the upper side wall of the air filter cartridge 55, an air inlet pipe 554 is fixedly mounted on the upper end of the delivery pipe 553, the air inlet pipe 554 is fixedly mounted inside the heat-insulating fixed round head 52, and an output pipe of the air inlet pipe 554 penetrates the inner wall of the mounting frame 51 and extends into between the inner heat-conducting ring 522 and the hot air exchange ring 523;

[0045] In this embodiment, the fan 54 works to filter the air through the air filter net 552 inside the air filter cartridge 55, and then transmits the air to the hot air exchange circle 523 and the inner heat conductive circle 522 through the delivery pipe 553 and the air inlet pipe 554. The air filter net 552 can be maintained and cleaned by pulling out and disassembling the cover 551. The ventilation groove 5231 is arranged on the inner side of the hot air exchange circle 523 so that the air can fully contact with the electric heating component 521 to absorb heat. The closed partition plate 524 seals the inner heat conductive circle 522 and the hot air exchange circle 523 to form a closed loop, so that the hot air can only be discharged through the gap of the inner heat conductive circle 522. The heat dissipation groove 531 on the outer side of the hollow hot pressing roller 53 can release heat. The limit frame 535 and the movable push head 5351 contact the outer wall of the inner heat conductive circle 522 to transfer heat to the hollow hot pressing roller 53. When the hollow hot pressing roller 53 rotates, the movable push head 5351 passes through the gap of the inner heat conductive circle 522. When the heat dissipation pressure is too low, the hot air in the air vent 532 is discharged through the hot air outlet 533 and the heat dissipation groove 531, and the contact area of ​​the composite non-woven fabric is hot-pressed. The short air duct 534 can further guide the hot air to enter the inner layer of the composite non-woven fabric, so that the inner hot-melt fiber transition layer 4 is melted. The hot pressing sheet 532 is connected to the arc-shaped wind guide plate 5251 because of the connecting rod 5321. As the hollow hot pressing roller 53 rotates, it produces a telescopic movement to uniformly press the composite non-woven fabric. The connecting plate 526 and the elastic gasket 5261 cooperate to compress and fix the movable sealing plate 525. As the movable pushing head 5351 is lifted up, it moves up and down intermittently to release the hot air, so that the heat is accumulated and then released, which accelerates the flow of hot air and makes the hot pressing efficiency of the composite non-woven fabric higher. Embodiment 5

[0046] See also Figures 1 to 12 On the basis of the fourth embodiment, in order to make the contact hot pressing between the hot pressing sheet 532 and the composite non-woven fabric more effective, this embodiment further proposes that an elastic push plate 5322 is fixedly installed between the inner surface of the hot pressing sheet 532 and the outer surface of the hollow hot pressing roller 53, and an indentation groove 5323 is opened on the surface of the hot pressing sheet 532;

[0047] In this embodiment, the elastic push plate 5322 pushes the heat pressing sheet 532 outward so that it can fully press the surface of the non-woven fabric. At the same time, the elastic push plate 5322 is arranged not only to allow hot air to pass through, but also to provide additional physical interlocking effect when the composite non-woven fabric passes through, thereby promoting interlayer bonding and improving the uniformity of material distribution.

[0048] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a high-strength needle-punched composite nonwoven fabric, characterized in that: The following steps are involved: Step 1: Raw material preparation: Select appropriate fiber raw materials according to the performance requirements of the final product and pre-treat the fibers; Step 2: Fiber web formation: the processed fibers are evenly fed into the web forming machine through an automatic feeding system, and a uniform fiber web layer is formed through air combing; Step 3: Needle Punch Reinforcement: The web is fed into a needle punching machine, and the high-speed needles penetrate the web to form physical cross-links between the fibers. Step 4, adding an intermediate layer: After pre-needling the fiber web, add a hot-melt fiber transition layer, and continue with the main needling. After the main needling, add a water-absorbing intermediate layer and a hot-melt fiber transition layer in sequence, and then continue with the post-needling. Finally, lay a surface film layer on the surface layer; Step 5: Hot-melt compounding: A specially designed hot-pressing device is used to hot-press the reset non-woven fabric after needle punching. The hot-melt fiber transition layer bonds the multiple layers of materials together during the hot-pressing process. Step 6: Post-processing: low-temperature ironing is used to stabilize the fiber structure, coating, printing, and antistatic treatment are performed according to market demand, and finally quality inspection is performed. The finished needle-punched composite non-woven fabric that passes the quality inspection is cut and wound according to specification requirements, and is prepared for packaging and transportation; The hot pressing device proposed in step 5 comprises a hot pressing equipment assembly (5), a transmission equipment assembly (6) is arranged below the hot pressing equipment assembly (5), the hot pressing equipment assembly (5) comprises a mounting frame (51), and heat-insulating fixed round heads (52) are symmetrically fixedly installed on the inner walls of both sides of the mounting frame (51), an inner heat-conducting ring (522) and a hot air exchange ring (523) are fixedly installed between two groups of the heat-insulating fixed round heads (52), the hot air exchange ring (523) is arranged on the inner side of the inner heat-conducting ring (522), a hollow hot pressing roller (53) is rotatably installed on the outer surface of the inner heat-conducting ring (522), and ventilation grooves (523) are evenly opened on the side walls of the hot air exchange ring (523). 5231), a notch is provided below the inner heat-conducting ring (522), a closed baffle (524) is fixedly installed above the notch of the inner heat-conducting ring (522), the upper end of the closed baffle (524) is fixedly connected to the outer surface of the hot air exchange ring (523), a movable closed plate (525) is provided at the notch of the inner heat-conducting ring (522), an arc-shaped wind guide plate (5251) is symmetrically fixedly installed in the middle of the movable closed plate (525), a connecting plate (526) is symmetrically provided above the movable closed plate (525), the connecting plate (526) is fixedly installed on the inner surface of the hot air exchange ring (523), and a lower surface of the connecting plate (526) is fixedly installed An elastic gasket (5261), the lower end of the elastic gasket (5261) is fixedly connected to the upper surface of the movable closing plate (525), the surface of the hollow hot pressing roller (53) is evenly provided with heat dissipation grooves (531) and hot air exhaust outlets (533), the heat dissipation grooves (531) and the hot air exhaust outlets (533) are staggeredly distributed, a hot pressing sheet (532) is arranged on the outside of the heat dissipation grooves (531), a short air duct (534) adapted to the hot air exhaust outlet (533) is fixedly installed on the outer surface of the hollow hot pressing roller (53), and a limiting frame (535) is evenly distributed on the inner side of the hollow hot pressing roller (53), and the limiting frame (535) is fixedly installed on the inner side of the hollow hot pressing roller (53). On the surface, a movable push head (5351) is movably installed inside the limit frame (535), a spring (5352) is fixedly installed on one side surface of the movable push head (5351), one end of the spring (5352) is fixedly connected to the inner surface of the hollow hot pressing roller (53), a connecting pull rod (5321) is symmetrically rotatably installed on the inner surface of the hot pressing sheet (532), one end of the connecting pull rod (5321) is rotatably connected to the side surface of the movable push head (5351), an elastic push plate (5322) is fixedly installed between the inner surface of the hot pressing sheet (532) and the outer surface of the hollow hot pressing roller (53), and an indentation groove (5323) is provided on the surface of the hot pressing sheet (532).

2. The method for preparing a high-strength needle-punched composite nonwoven fabric according to claim 1, characterized in that: The step one also includes opening, mixing and impurity removal pretreatment of the fibers, and the step three includes three stages: pre-needling, main needling and post-needling.

3. The method for preparing a high-strength needle-punched composite nonwoven fabric according to claim 2, characterized in that: An electric heating component (521) is fixedly installed inside a group of the heat-insulating fixed round heads (52), the electric heating component (521) is arranged inside the hot air exchange circle (523), and a temperature control device is arranged outside the electric heating component (521).

4. The method for preparing a high-strength needle-punched composite nonwoven fabric according to claim 3, characterized in that: A fan (54) is arranged on one side of the mounting frame (51), and an air filter cartridge (55) is arranged above the fan (54). The air filter cartridge (55) is fixedly mounted on the side wall of the mounting frame (51). A disassembly cover (551) is snap-fitted to one end of the air filter cartridge (55), and an air filter screen (552) is snap-fitted to the inside of the air filter cartridge (55). An output pipe of the fan (54) passes through the inner wall of the other side of the air filter cartridge (55) and extends into the inside of the air filter screen (552). A delivery pipe (553) is fixedly mounted above the side wall of the air filter cartridge (55), and an air inlet pipe (554) is fixedly mounted at the upper end of the delivery pipe (553). The air inlet pipe (554) is fixedly mounted inside the heat-insulating fixed round head (52), and an output pipe of the air inlet pipe (554) passes through the inner wall of the mounting frame (51) and extends between the inner heat-conducting ring (522) and the hot air exchange ring (523).

5. The method for preparing a high-strength needle-punched composite nonwoven fabric according to claim 4, characterized in that: A motor (56) is fixedly mounted on the upper side wall of the mounting frame (51); a driving gear (561) is fixedly mounted on the output shaft of the motor (56); a rack (562) is provided below the driving gear (561); the rack (562) is fixedly mounted on the outer side of one end of the hollow hot pressing roller (53) by means of bolts; the outer surface of the rack (562) meshes with the outer surface of the driving gear (561).

6. A high-strength needle-punched composite nonwoven fabric, prepared according to the method for preparing a high-strength needle-punched composite nonwoven fabric as claimed in claim 1, comprising a nonwoven needle-punched fiber web layer (1), characterized in that: A water-absorbing interlayer (2) is arranged on the outer side of the non-woven needle-punched fiber web layer (1), a surface film layer (3) is arranged on the outer side of the water-absorbing interlayer (2), and a hot-melt fiber transition layer (4) is arranged on the surface of both the non-woven needle-punched fiber web layer (1) and the water-absorbing interlayer (2).

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