A highly breathable antibacterial nonwoven fabric and its preparation process

Abstract

The present invention discloses a highly breathable antibacterial nonwoven fabric and a preparation process thereof, and relates to the field of nonwoven fabrics. The present invention adopts a three-layer composite structure design, combines the high air permeability of microporous PLA fiber, the antibacterial function of melt-blown PP fiber and the comfort of antistatic PP fiber, and introduces a diamond lattice mesh reinforcement structure in the middle layer. The fiber used in the diamond lattice mesh reinforcement structure is a composite fiber of PLA fiber and UHMWPE fiber, which greatly improves the tensile strength and durability. The overall structure is light and environmentally friendly, and has excellent air permeability, antibacterial and mechanical properties, meeting the dual needs of high performance and sustainable development.

Description

Technical Field

[0001] The present invention relates to the field of non-woven fabrics, and in particular to a highly breathable antibacterial non-woven fabric and a preparation process thereof. Background Art

[0002] Non-woven fabric is a textile material made by directly bonding fibers by physical or chemical methods, without going through the traditional spinning and weaving process. It is usually made of polypropylene (PP), polyester (PET) or other polymer materials, and has the characteristics of light weight, high strength, good air permeability, low cost, and biodegradability. It is widely used in medical, packaging, agriculture, home furnishing and other fields. Because its structure is similar to cloth, it is called "non-woven fabric", but it is essentially a non-woven fabric.

[0003] Chinese patent application number: CN201611272815.0 discloses an antibacterial nonwoven fabric, including a spunbond nonwoven fabric layer, a first antibacterial nonwoven fabric layer, a second antibacterial nonwoven fabric layer and a viscose nonwoven fabric layer, the first antibacterial nonwoven fabric layer and the second antibacterial nonwoven fabric layer are located between the anti-adhesive nonwoven fabric layer and the viscose nonwoven fabric layer, the first antibacterial nonwoven fabric layer is located above the second antibacterial nonwoven fabric layer, and a meltblown nonwoven fabric layer is also provided between the first antibacterial nonwoven fabric layer and the second antibacterial nonwoven fabric layer. The present invention has a first antibacterial nonwoven fabric layer and a second antibacterial nonwoven fabric layer, the antibacterial component is not easy to fall off, the antibacterial component can be slowly released, and the antibacterial effect is produced for a long time, and the spunbond nonwoven fabric layer, the meltblown nonwoven fabric layer and the viscose nonwoven fabric layer make the nonwoven fabric surface soft, fluffy, and have excellent texture. While having antibacterial function, it also has good water absorption and comfort, high antibacterial performance, long-lasting, safe and broad spectrum, and can be widely used in sanitary products, safe and hygienic.

[0004] The above patents and prior art have the following problems in actual use: they have antibacterial function but the overall breathability is weak, and the overall tensile strength is weak and the durability is poor; during the processing, the antibacterial agent penetrates by itself after being added, the penetration effect is weak, the uniformity is insufficient, and the degree of fit after the multi-layer structure is combined is low. Summary of the invention

[0005] Therefore, in order to solve the above-mentioned shortcomings, the present invention provides a highly breathable antibacterial non-woven fabric and a preparation process thereof.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a highly breathable antibacterial non-woven fabric and its preparation process, including a surface layer, the surface layer adopts microporous PLA fiber, an intermediate layer is arranged at the bottom of the surface layer, the intermediate layer adopts melt-blown PP fiber and is added with an antibacterial agent, a bottom layer is arranged at the bottom of the intermediate layer, the bottom layer adopts PP fiber with antistatic function, a reinforcing mesh layer is attached to the top and bottom of the intermediate layer, the reinforcing mesh layer is a diamond lattice fiber mesh structure, and is a mixture of PLA fiber and UHMWPE fiber in a ratio of 7:3, and the surface layer, the intermediate layer and the bottom layer are combined by hot pressing.

[0007] Preferably, the specific steps are as follows:

[0008] S1 Material preparation:

[0009] Surface material: microporous PLA fiber with pore size ranging from 0.1-10 microns, antibacterial coating is nanosilver with particle size <50 nm;

[0010] Middle layer material: melt-blown PP fiber, adding antibacterial agent, and preparing antibacterial fiber through melt-blowing technology;

[0011] Bottom material: antistatic PP fiber, antistatic agent polyetheramide added;

[0012] Reinforced mesh material: a mixture of PLA fiber and UHMWPE fiber;

[0013] S2 surface preparation: Microporous PLA fibers are manufactured by electrospinning process, the fiber pore size is controlled at 0.1-10 microns, nanosilver is evenly coated on the fiber surface by spraying, and dried at 80-100℃ for 30 minutes. The microporous PLA fibers are meshed by electrospinning method, the number of fiber cross points is controlled, and the air permeability is optimized;

[0014] Preparation of S3 middle layer: melt-blown PP fiber is mixed with antibacterial agent, with the mass ratio of antibacterial agent being 2%-5%, and antibacterial melt-blown fiber is produced by melt-blown process, and then the middle layer is stabilized again by auxiliary stabilization device to improve the uniformity of antibacterial agent in the middle layer;

[0015] Preparation of S4 reinforcement mesh layer: PLA fiber and UHMWPE fiber melt were mixed in a ratio of 7:3, and high-strength composite fibers were prepared using a fiber drawing machine. The composite fibers were woven into a diamond lattice mesh structure with a mesh aperture of 2-4 mm. The diamond lattice structures were placed on the top and bottom of the middle layer respectively.

[0016] S5 bottom layer preparation: adding antistatic agent to PP melt to prepare PP fiber with antistatic property, and processing the antistatic PP fiber into non-woven fabric structure by needle punching;

[0017] S6 three-layer composite structure assembly: stack the surface layer, the middle layer including the reinforcing mesh layer, and the bottom layer in order, and perform lamination in a hot press at a temperature of 130-150°C, a pressure of 1.5-2 MPa, and a time of 30 seconds. Use a trimming device to trim the edges of the fabric to ensure size and surface flatness;

[0018] S7 post-treatment: The composite non-woven fabric is subjected to low-temperature curing treatment at 80-100°C for 20 minutes, and is stabilized with an auxiliary stabilization device.

[0019] Preferably, the auxiliary stabilization device includes a base plate for support, a support rod arranged on the top of the base plate, a transmission box arranged on the right end of the top of the base plate, an adjustment mechanism installed on the top of the support rod, and a guide mechanism arranged on the top of the adjustment mechanism, and the guide mechanism is driven by the adjustment mechanism to adjust the conveying angle of the passing fabric.

[0020] Preferably, the transmission box includes a box body arranged at the top right end of the base plate, a driving motor arranged at the lower end of the box body, a driving wheel connected to the output shaft of the driving motor, a synchronous belt arranged on the outside of the driving wheel, and a driven wheel arranged at the other end of the synchronous belt, and the middle part of the driven wheel is connected to the adjustment mechanism.

[0021] Preferably, the adjustment mechanism includes a transmission shaft that passes through the box and is connected to the driven wheel, pulleys arranged at the front and rear ends of the transmission shaft, a belt arranged on the outside of the pulley, a first lifting wheel connected to the transmission shaft at the inner lower end, a connecting shaft arranged at the outer upper end of the first lifting wheel, a second lifting wheel connected to the connecting shaft at the inner upper end, a first lifting rod arranged at the top of the first lifting wheel, and a second lifting rod arranged at the top of the second lifting wheel, the first lifting rod and the second lifting rod are hinged at their right ends, and the other ends of the first lifting rod and the second lifting rod are respectively connected to the guide mechanism.

[0022] Preferably, the outer side of the pulley is connected to another group of pulleys at the left end through a belt, and the other group of pulleys is connected to the inner lower end of another group of first lifting wheels through a shaft rod.

[0023] Preferably, a group of supports are provided at the hinged positions of the first push rod and the second push rod, and another group of supports are provided on the transmission shaft between the first lifting wheel and the pulley, and the bottoms of the two groups of supports are connected to the support rod.

[0024] Preferably, the guiding mechanism includes a first bracket having two ends of the bottom hinged to two groups of second top rods, a second bracket having two ends of the bottom hinged to two groups of first top rods, support blocks respectively arranged on the top of the first bracket and the second bracket, a limiting roller arranged on the inner upper end of the support block, a first guide roller arranged on the inner lower end of the support block corresponding to the second bracket, and a second guide roller arranged on the inner lower end of the support block corresponding to the first bracket.

[0025] Preferably, a pressure strip is fixed on the outer side of the first guide roller, a scraping layer is coated on the outer side of the second guide roller, and raised particles are arranged on the outer side of the scraping layer.

[0026] Beneficial effects of the present invention:

[0027] The highly breathable antibacterial non-woven fabric of the present invention adopts a three-layer composite structure design, combining the high air permeability of microporous PLA fiber, the antibacterial function of melt-blown PP fiber and the comfort of antistatic PP fiber, while introducing a diamond lattice mesh reinforcement structure in the middle layer, and the fiber used in the diamond lattice mesh reinforcement structure is a composite fiber of PLA fiber and UHMWPE fiber, which greatly improves the tensile strength and durability. The overall structure is light and environmentally friendly, has excellent air permeability, antibacterial and mechanical properties, and meets the dual needs of high performance and sustainable development.

[0028] The present invention provides an auxiliary stabilizing device during the preparation process of the non-woven fabric, thereby achieving the offset movement of the limiting roller and the guide roller, so that the fabric can be pressurized during the transmission process and evenly infiltrated with the antibacterial agent. At the same time, the surface of the fabric is treated by the layering strip and the scraping layer, which effectively improves the uniformity of the fabric infiltration and the stability of the multi-layer structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the present invention;

[0030] Figure 2 It is a schematic diagram of the local structure of the middle layer of the present invention;

[0031] Figure 3 It is a schematic diagram of the structure of the auxiliary stabilization device of the present invention;

[0032] Figure 4 It is a schematic diagram of the transmission box structure of the present invention;

[0033] Figure 5 It is a schematic diagram of the structure of the regulating mechanism of the present invention;

[0034] Figure 6 It is a schematic diagram of the partial structure of the regulating mechanism of the present invention;

[0035] Figure 7 It is a schematic diagram of the connection structure of the first lifting wheel and the second lifting wheel of the present invention;

[0036] Figure 8 It is a schematic diagram of the structure of the first guide roller of the present invention;

[0037] Fig. 9 It is a schematic diagram of the second guide roller structure of the present invention.

[0038] Among them: surface layer-a, middle layer-b, bottom layer-c, reinforcing mesh layer-b1, base plate-1, support rod-2, transmission box-3, adjustment mechanism-4, guide mechanism-5, box body-31, driving motor-32, driving wheel-33, synchronous belt-34, driven wheel-35, transmission shaft-41, pulley-42, belt-43, first lifting wheel-44, connecting shaft-45, second lifting wheel-46, first push rod-47, second push rod-48, first bracket-51, second bracket-52, support block-53, limiting roller-54, first guide roller-55, second guide roller-56, pressure strip-551, scraping layer-561. DETAILED DESCRIPTION

[0039] In order to further explain the technical solution of the present invention, it is described in detail below through specific embodiments.

[0040] See also Figure 1 and Figure 2 The present invention provides a highly breathable antibacterial non-woven fabric, including a surface layer a, the surface layer a adopts microporous PLA fiber to ensure high air permeability and inhibit bacterial attachment, an intermediate layer b is arranged at the bottom of the surface layer a, melt-blown PP fiber is adopted as a carrier of antibacterial additives, and antibacterial agents are added into the melt-blown PP fiber, and the antibacterial fiber is prepared by melt-blowing technology, a bottom layer c is arranged at the bottom of the intermediate layer b, the bottom layer c is PP fiber with antistatic function, which helps to improve the wearing comfort and safety of the fabric, the surface layer a, the intermediate layer b and the bottom layer c are combined by hot pressing, and a reinforcing mesh layer b1 is attached to the top and bottom of the intermediate layer b, and the reinforcing mesh layer b1 is a diamond lattice fiber mesh structure, which is a mixture of PLA fiber and UHMWPE fiber in a ratio of 7:3.

[0041] A preparation process of a highly breathable antibacterial non-woven fabric, S1 material preparation: surface layer a material: microporous PLA fiber with a pore size range of 3 microns, and the antibacterial coating is nanosilver with a particle size of <50 nm; middle layer b material: melt-blown PP fiber, adding an antibacterial agent, and preparing the antibacterial fiber through melt-blowing technology; bottom layer c material: antistatic PP fiber, adding antistatic agent polyetheramide; reinforcing mesh layer b1 material: a mixture of PLA fiber and UHMWPE fiber; S2 surface layer a preparation: microporous PLA fiber is manufactured through an electrospinning process, the fiber pore size is controlled at 3 microns, and nanosilver is evenly coated on the fiber surface by spraying, and dried at 90°C for 30 minutes, and the microporous PLA fiber is formed into a mesh by an electrospinning method, the number of fiber intersections is controlled, and the air permeability is optimized; S3 middle layer b preparation: melt-blown PP fiber is mixed with an antibacterial agent, the antibacterial agent is 3.5% by mass, and the antibacterial melt-blown fiber is produced by a melt-blowing process, and then centered by an auxiliary stabilization device. The interlayer b is stabilized again to improve the uniformity of the antimicrobial agent in the middle layer b; S4 Preparation of reinforced mesh layer b1: PLA fiber and UHMWPE fiber melt are mixed in a ratio of 7:3, and high-strength composite fibers are prepared using a fiber drawing machine. The composite fibers are woven into a diamond lattice mesh structure, and the mesh aperture is controlled to be 3mm. The diamond lattice structure is placed on the top and bottom of the middle layer b respectively; S5 Preparation of bottom layer c: Antistatic agent is added to the PP melt to prepare PP fiber with antistatic properties, and the antistatic PP fiber is processed into a non-woven fabric structure using a needle punching method; S6 Assembly of three-layer composite structure: The surface layer a, the middle layer b (including the reinforced mesh layer b1), and the bottom layer c are stacked in order and laminated in a hot press at a temperature of 140°C and a pressure of 1.75. MPa, time is 30 seconds, use trimming equipment to trim the edge of the fabric to ensure size and surface flatness; S7 post-treatment: low-temperature curing treatment of the composite non-woven fabric at 90°C for 20 minutes, and stabilize it with an auxiliary stabilization device; S8 quality inspection: use Gurley air permeability tester to test the air permeability to ensure the target value (100-150 L / m² / s), test the antibacterial performance according to AATCC100 standard to ensure the antibacterial rate ≥99%, and use ISO 13934-1 standard to test the tensile performance, the target value is ≥30% increase in original strength.

[0042] See also Figure 3 The auxiliary stabilization device includes a base plate 1 for support, a support rod 2 is vertically fixed on the top of the base plate 1, the top of the support rod 2 is connected to an adjusting mechanism 4, the top of the adjusting mechanism 4 is connected to a guide mechanism 5, and the guide mechanism 5 is driven by the adjusting mechanism 4 to adjust the conveying angle of the fabric, so as to facilitate the uniform infiltration of the antibacterial agent into the fabric, and also facilitate the fitting and fixing of multiple layers of the fabric. A transmission box 3 is installed on the right end of the top of the base plate 1, and the upper end of the transmission box 3 is connected to the adjusting mechanism 4 for driving it.

[0043] See also Figure 4 The transmission box 3 includes a box body 31 arranged at the top right end of the base plate 1, a driving motor 32 arranged at the lower end of the box body 31, the front end output shaft of the driving motor 32 is connected to the driving wheel 33, the outer side of the driving wheel 33 is synchronously rotated with the driven wheel 35 through a synchronous belt 34, and the middle part of the driven wheel 35 is connected to the adjustment mechanism 4.

[0044] See also Figure 5-Figure 9 The adjusting mechanism 4 includes a transmission shaft 41 that penetrates the box body 31 and is connected to the middle of the driven wheel 35. The front and rear ends of the transmission shaft 41 are respectively connected to pulleys 42. The outer side of the pulley 42 is connected to another group of pulleys 42 at the left end through a belt 43. A first lifting wheel 44 is arranged behind the outer sides of the two groups of pulleys 42. The lower end of the first lifting wheel 44 is connected to the transmission shaft 41. The other group of pulleys 42 is connected to the lower end of the other group of first lifting wheels 44 through an axle rod. The upper end of the back of the first lifting wheel 44 is connected to the upper end of the second lifting wheel 46 through a connecting shaft 45. The top of the first lifting wheel 44 contacts the first push rod 47, and the top of the second lifting wheel 46 contacts the second push rod 48. The right ends of the first push rod 47 and the second push rod 48 are hinged, and the other ends of the first push rod 47 and the second push rod 48 are respectively connected to the guide mechanism 5;

[0045] A set of supports is provided at the hinged position of the first push rod 47 and the second push rod 48, and another set of supports is provided between the first lifting wheel 44 and the pulley 42 on the transmission shaft 41, and the bottoms of the two sets of supports are connected to the support rod 2, which supports them;

[0046] The guide mechanism 5 comprises a first bracket 51 with two sets of second push rods 48 hinged at both ends of the bottom and a second bracket 52 with two sets of first push rods 47 hinged at both ends of the bottom. Support blocks 53 are fixed on the top of the first bracket 51 and the second bracket 52. Four sets of support blocks 53 are arranged on the top of each bracket. A limiting roller 54 is fixed on the inner upper end of the support block 53. A second guide roller 56 is rotatably arranged on the inner lower end of the first bracket 51 corresponding to the support block 53. A first guide roller 55 is rotatably arranged on the inner lower end of the second bracket 52 corresponding to the support block 53.

[0047] A pressure strip 551 is fixed on the outer side of the first guide roller 55 , and a scraping layer 561 is coated on the outer side of the second guide roller 56 . Protruding particles are arranged on the outer side of the scraping layer 561 .

[0048] The specific implementation process of the auxiliary stabilization device is as follows:

[0049] When it is necessary to make the antibacterial agent evenly infiltrate the fabric or stabilize the multi-layer structure, the fabric is pulled out from the previous station and passes through each set of limiting rollers and guide rollers in turn, and then pulled out to the next station;

[0050] Then the driving motor 32 inside the box body 31 is started to work, and the driving motor 32 drives the driving wheel 33 to rotate, and the driving wheel 33 drives the driven wheel 35 to rotate through the synchronous belt 34, and the driven wheel 35 can drive the transmission shaft 41 to make the pulley 42 rotate accordingly, and the pulley 42 makes the other set of pulleys 42 rotate synchronously through the belt 43. At this time, the first lifting wheel 44 and the second lifting wheel 46 rotate eccentrically under the action of the shaft rod and the connecting shaft 45, and can act on the first push rod 47 and the second push rod 48 in contact with the top during the rotation process, so that they move up and down, and act on the first bracket 51 and the second bracket 52 connected at the top. In the process of the two sets of brackets moving up and down, the limiting roller 54 and the guide roller inside the support block 53 can be moved up and down, and the roller bodies in the two sets of brackets are staggered to facilitate the pressure on the fabric when it passes through, and the pressure strips 551 and the scraping layer 561 on the outside of the first guide roller 55 and the second guide roller 56 can assist in scraping and pressing the passing fabric.

[0051] The above description is only a preferred example of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A process for preparing a highly breathable antibacterial nonwoven fabric, characterized in that: The specific steps are as follows: S1 Material preparation: Surface material: microporous PLA fiber with pore size ranging from 0.1-10 microns, antibacterial coating is nanosilver with particle size <50nm; Middle layer material: melt-blown PP fiber, adding antibacterial agent, and preparing antibacterial fiber through melt-blowing technology; Bottom material: antistatic PP fiber, antistatic agent polyetheramide added; Reinforced mesh material: a mixture of PLA fiber and UHMWPE fiber; S2 surface preparation: Microporous PLA fibers are manufactured by electrospinning process, the fiber pore size is controlled at 0.1-10 microns, nanosilver is evenly coated on the fiber surface by spraying, and dried at 80-100℃ for 30 minutes. The microporous PLA fibers are meshed by electrospinning method, the number of fiber cross points is controlled, and the air permeability is optimized; Preparation of S3 middle layer: melt-blown PP fiber is mixed with antibacterial agent, with the mass ratio of antibacterial agent being 2%-5%, and antibacterial melt-blown fiber is produced by melt-blown process, and then the middle layer is stabilized again by auxiliary stabilization device to improve the uniformity of antibacterial agent in the middle layer; Preparation of S4 reinforcement mesh layer: PLA fiber and UHMWPE fiber melt were mixed in a ratio of 7:3, and high-strength composite fibers were prepared using a fiber drawing machine. The composite fibers were woven into a diamond lattice mesh structure with a mesh aperture of 2-4 mm. The diamond lattice structures were placed on the top and bottom of the middle layer respectively. S5 bottom layer preparation: adding antistatic agent to PP melt to prepare PP fiber with antistatic property, and processing the antistatic PP fiber into non-woven fabric structure by needle punching; S6 three-layer composite structure assembly: stack the surface layer, the middle layer including the reinforcing mesh layer, and the bottom layer in order, and perform lamination in a hot press at a temperature of 130-150°C, a pressure of 1.5-2 MPa, and a time of 30 seconds. Use a trimming device to trim the edges of the fabric to ensure size and surface flatness; S7 post-treatment: low-temperature curing treatment of the composite non-woven fabric at 80-100°C for 20 minutes, and stabilization with auxiliary stabilization device; The auxiliary stabilizing device includes a base plate for supporting, a support rod arranged on the top of the base plate, a transmission box arranged on the right end of the top of the base plate, an adjustment mechanism installed on the top of the support rod, and a guide mechanism arranged on the top of the adjustment mechanism, wherein the guide mechanism is driven by the adjustment mechanism to adjust the conveying angle of the passing fabric; The transmission box includes a box body arranged at the right end of the top of the base plate, a driving motor arranged at the lower end of the box body, a driving wheel connected to the output shaft of the driving motor, a synchronous belt arranged at the outside of the driving wheel, and a driven wheel arranged at the other end of the synchronous belt, and the middle of the driven wheel is connected to the adjustment mechanism; The adjustment mechanism includes a transmission shaft that passes through the box and is connected to the driven wheel, pulleys arranged at the front and rear ends of the transmission shaft, a belt arranged on the outside of the pulley, a first lifting wheel connected to the transmission shaft at the inner lower end, a connecting shaft arranged at the outer upper end of the first lifting wheel, a second lifting wheel connected to the connecting shaft at the inner upper end, a first push rod arranged at the top of the first lifting wheel, and a second push rod arranged at the top of the second lifting wheel, the first push rod and the second push rod are hinged at their right ends, and the other ends of the first push rod and the second push rod are respectively connected to the guide mechanism.

2. The process for preparing a highly breathable antibacterial nonwoven fabric according to claim 1, characterized in that: The outer side of the pulley is connected to another group of pulleys at the left end through a belt, and the other group of pulleys is connected to the inner lower end of another group of first lifting wheels through a shaft rod.

3. The process for preparing a highly breathable antibacterial nonwoven fabric according to claim 2, characterized in that: A set of supports are provided at the hinged positions of the first push rod and the second push rod, and another set of supports is provided on the transmission shaft between the first lifting wheel and the pulley, and the bottoms of the two sets of supports are connected to the support rods.

4. The process for preparing a highly breathable antibacterial nonwoven fabric according to claim 1, characterized in that: The guiding mechanism includes a first bracket with two groups of second top rods hinged at both ends of the bottom, a second bracket with two groups of first top rods hinged at both ends of the bottom, support blocks respectively arranged on the top of the first bracket and the second bracket, a limiting roller arranged on the inner upper end of the support block, a first guide roller arranged on the inner lower end of the support block corresponding to the second bracket, and a second guide roller arranged on the inner lower end of the support block corresponding to the first bracket.

5. The process for preparing a highly breathable antibacterial nonwoven fabric according to claim 4, characterized in that: A pressure strip is fixed on the outer side of the first guide roller, a scraping layer is coated on the outer side of the second guide roller, and raised particles are arranged on the outer side of the scraping layer.

6. The nonwoven fabric prepared by the process for preparing a highly breathable antibacterial nonwoven fabric according to claim 1, characterized in that: It includes a surface layer, which is made of microporous PLA fiber. An intermediate layer is arranged at the bottom of the surface layer, which is made of melt-blown PP fiber and has an antibacterial agent added thereto. A bottom layer is arranged at the bottom of the intermediate layer, which is made of PP fiber with antistatic function. A reinforcing mesh layer is attached to the top and bottom of the intermediate layer. The reinforcing mesh layer is a diamond lattice fiber mesh structure, which is a mixture of PLA fiber and UHMWPE fiber in a ratio of 7:

3. The surface layer, the intermediate layer and the bottom layer are combined by hot pressing.

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