A process for hot melt bonding of a concave-convex surface layer melt-blown cloth and a sound insulation board

Abstract

This invention relates to the field of sound insulation materials technology, specifically to a hot-melt bonding process for a textured surface layer meltblown fabric and a sound insulation board, comprising the following steps: Preparation of the textured surface layer meltblown fabric: Polypropylene, textured surface forming agent, antioxidant, lubricant, and pore-forming agent are mixed evenly, fed into a twin-screw extruder for melt mixing, and then spun through a gradient microporous spinneret. After cooling, receiving, and winding, the textured surface layer meltblown fabric is obtained; Pretreatment of the sound insulation board: The sound insulation board substrate is placed in a forced-air drying oven to dry, removing surface moisture and impurities, and then naturally cooled to room temperature. This invention, by designing the textured surface layer meltblown fabric structure and rationally selecting the textured surface forming agent and pore-forming agent, significantly increases the contact area between the meltblown fabric and the sound insulation board, allowing the hot melt adhesive to more fully fill the interface gaps, significantly improving the bonding strength of the composite structure, effectively avoiding peeling, and extending the product's service life.

Description

Technical Field

[0001] This invention relates to the field of sound insulation materials technology, specifically to a hot-melt bonding process between a textured surface layer meltblown fabric and a sound insulation board. Background Technology

[0002] In the field of sound insulation materials, the composite structure of meltblown fabric and sound insulation board is widely used in various scenarios such as construction and transportation due to its advantages of both lightweight and sound insulation. Currently, the industry generally uses conventional meltblown fabric and sound insulation board for hot-melt bonding, but the existing process has many problems that urgently need to be solved.

[0003] In existing lamination processes, meltblown fabric is mostly planar, resulting in limited contact area with the sound insulation board. This leads to insufficient interfacial adhesion, making it prone to peeling and affecting product lifespan. Furthermore, the raw material ratios lack targeted optimization, some solutions do not add specialized functional additives, or the additive selection is incompatible with the substrate characteristics, resulting in poor structural stability of the composite structure and susceptibility to deformation during use.

[0004] In terms of bonding processes, most methods employ a single pressure control mode, which cannot precisely adjust the pressure according to the different stages of material bonding, further exacerbating the problem of loose interfacial adhesion. Furthermore, some processes omit the substrate pretreatment step, allowing moisture and impurities on the sound insulation board surface to directly affect the wetting effect of the hot melt adhesive, leading to a decline in bonding quality.

[0005] Meanwhile, existing technologies lack coordinated design of meltblown fabric preparation, bonding parameters, and raw material characteristics. They often simply use existing single process parameters, making it difficult to balance the comprehensive indicators of composite boards such as sound insulation performance and weather resistance. This fails to meet the requirements of high-end application scenarios for high-performance and high-stability materials, thus limiting the further expansion of its application scope. Summary of the Invention

[0006] The primary objective of this invention is to provide a process for hot-melt bonding of a textured surface layer meltblown fabric with a sound insulation board.

[0007] A further objective of this invention is to provide a process for hot-melt bonding of a textured surface layer meltblown fabric to a sound insulation board, comprising the following steps:

[0008] (1) Preparation of uneven boundary layer meltblown fabric: Polypropylene, uneven structure forming agent, antioxidant, lubricant and pore forming agent are mixed evenly, put into a twin screw extruder for melt mixing, and then spun through a gradient micro-hole spinneret. After cooling, receiving and winding, uneven boundary layer meltblown fabric is obtained.

[0009] (2) Pretreatment of sound insulation board: Place the sound insulation board substrate in a forced-air drying oven to dry it, remove surface moisture and impurities, and then let it cool naturally to room temperature.

[0010] (3) Hot melt bonding: The hot melt adhesive is evenly spread on the uneven surface of the meltblown fabric of the uneven surface layer, and then stacked with the pre-treated sound insulation board and placed into the hot melt bonding machine. After preheating, segmented pressure bonding is adopted, and the first stage pressure holding and the second stage pressure holding are carried out in sequence to complete the hot melt bonding.

[0011] (4) Post-processing: The laminated composite board is placed in a constant temperature and humidity chamber for curing. After being taken out, the composite structure of the concave-convex surface layer meltblown cloth sound insulation board is obtained.

[0012] Preferably, in the raw material of the uneven surface layer meltblown fabric, the uneven structure forming agent is calcium carbonate, silicon dioxide or a composite system of the two, the antioxidant is 1010, 1076 or a composite system of the two, the lubricant is magnesium stearate, zinc stearate or a composite system of the two, and the pore-forming agent is polyethylene glycol, polypropylene glycol or a composite system of the two.

[0013] Preferably, the hot melt adhesive is an ethylene-vinyl acetate copolymer, a polyolefin hot melt adhesive, or a composite system of both.

[0014] Preferably, the sound insulation board substrate is a polyester fiber sound insulation board with a porosity of not less than 75%.

[0015] Preferably, in step (1), the extrusion temperature of the twin-screw extruder is 205 to 215°C, the screw speed is 300 to 310 r / min, the melt mixing time is 3 min, the spinneret pressure is 0.3 to 0.35 MPa, the cooling air velocity is 3 to 3.5 m / s, the receiving distance is 15 to 16 cm, and the winding speed is 5 to 5.5 m / min.

[0016] Preferably, in step (2), the drying temperature of the blower drying oven is 78 to 85°C and the drying time is 2 to 2.5 hours.

[0017] Preferably, in step (3), the preheating time is 30 to 32 s, the bonding temperature is 120 to 140 ℃, the bonding pressure of the first stage is 0.15 to 0.2 MPa, and the holding time is 10 to 15 s; the bonding pressure of the second stage is 0.4 to 0.45 MPa, and the holding time is 20 to 25 s; and the bonding speed is 1.8 to 2 m / min.

[0018] Preferably, in step (4), the temperature of the constant temperature and humidity chamber is 25 to 26°C, the humidity is 50 to 52%, and the curing time is 24 to 26 hours.

[0019] Preferably, when the convex-concave structure forming agent is a composite system of calcium carbonate and silica, the mass ratio of the two is 1:1; when the antioxidant is a composite system of 1010 and 1076, the mass ratio of the two is 2:1; when the lubricant is a composite system of magnesium stearate and zinc stearate, the mass ratio of the two is 3:1; and when the pore-forming agent is a composite system of polyethylene glycol and polypropylene glycol, the mass ratio of the two is 1:1.

[0020] Preferably, when the hot melt adhesive is a composite system of ethylene vinyl acetate copolymer and polyolefin hot melt adhesive, the mass ratio of the two is 2:1.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] 1. By designing a textured surface layer meltblown fabric structure and rationally selecting textured structure forming agents and pore-forming agents, this invention significantly increases the contact area between the meltblown fabric and the sound insulation board, enabling the hot melt adhesive to more fully fill the interface gaps, significantly improving the bonding strength of the composite structure, effectively preventing peeling, and extending the product's service life.

[0023] 2. This invention optimizes the raw material ratio system, and precisely selects the types and ratios of additives such as texture forming agents, antioxidants, and lubricants according to the characteristics of the substrate. Some solutions adopt a composite additive system, which not only strengthens the texture stability of the meltblown fabric, but also improves the anti-aging ability of the material, ensuring that the composite board maintains its structural integrity during long-term use.

[0024] 3. This invention adopts a segmented hot melt bonding process, and designs differentiated pressure and holding time for the initial wetting and later stabilization requirements. Combined with substrate pretreatment and posttreatment steps, it further improves the interface bonding effect, while enhancing the heat resistance and moisture resistance of the composite board, so that the product can maintain excellent performance in complex environments.

[0025] 4. This invention achieves simultaneous improvement in bonding strength, sound insulation performance, and structural stability by synergistically optimizing meltblown fabric preparation parameters, bonding process, and raw material characteristics. It solves the pain point of difficulty in achieving all performance aspects in existing technologies, broadens the application scenarios of composite sound insulation materials, and provides a reliable technical solution for high-end sound insulation needs. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1:

[0028] Raw material ratio:

[0029] The proportions of each raw material by weight are as follows:

[0030] Raw materials for the textured surface layer meltblown fabric: 90 parts polypropylene, 10 parts calcium carbonate as a texture-forming agent, 0.5 parts antioxidant 1010, 0.3 parts magnesium stearate as a lubricant, 1.2 parts polyethylene glycol PEG6000 as a pore-forming agent, and calcium carbonate with a particle size of 6μm.

[0031] Hot melt adhesive: 100 parts of ethylene vinyl acetate copolymer (EVA), VA content 28%, the amount used during lamination is 15% of the meltblown fabric mass;

[0032] Sound insulation board substrate: Polyester fiber sound insulation board, density 250kg / m³ 3 Thickness 10mm, porosity 75%.

[0033] Process steps:

[0034] Preparation of textured boundary layer meltblown fabric: Polypropylene, texture forming agent, antioxidant, lubricant, and pore-forming agent are mixed evenly according to the formula and fed into a twin-screw extruder. The extrusion temperature is set to 210℃, the screw speed to 300r / min, and after melt mixing for 3min, the fabric is spun through a gradient micro-orifice spinneret. The spinneret orifice diameter is 0.3mm, and the orifice diameter increases gradually along the spinneret direction. The spinneret pressure is 0.3MPa, the cooling air velocity is 3m / s, the receiving distance is 15cm, and the winding speed is 5m / min. A textured boundary layer meltblown fabric with a thickness of 2mm and a texture height of 0.4mm is prepared.

[0035] Pretreatment of sound insulation boards: Place the polyester fiber sound insulation boards into a forced-air drying oven and dry at 80°C for 2 hours to remove surface moisture and impurities. After removal, allow them to cool naturally to room temperature for later use.

[0036] Hot melt bonding: Hot melt adhesive is evenly spread on the uneven surface of the meltblown fabric (the bonding surface) of the surface layer. Then, the meltblown fabric and the sound insulation board are stacked together and placed into the hot melt bonding machine. The bonding temperature is set to 140℃, the preheating time to 30s, the first bonding pressure to 0.2MPa and the pressure holding time to 10s, the second bonding pressure to 0.4MPa and the pressure holding time to 20s, and the bonding speed to 2m / min to complete the hot melt bonding.

[0037] Post-processing: After bonding, the composite board is placed in a constant temperature and humidity chamber at 25℃ and 50% humidity for 24 hours. After removal, the final composite structure of the concave-convex boundary layer meltblown fabric sound insulation board is obtained.

[0038] Example 2:

[0039] This embodiment addresses the pain points of easy deformation of the concave-convex structure and suboptimal bonding strength in Embodiment 1. While retaining the same raw material types and process steps as in Embodiment 1, it optimizes the dosage of the concave-convex structure forming agent and key parameters of hot melt bonding to enhance structural stability and interfacial adhesion. The specific solution is as follows:

[0040] Raw material ratio adjustment:

[0041] Raw materials for the textured surface layer meltblown fabric: 85 parts polypropylene, 12 parts calcium carbonate as a texture-forming agent, 0.5 parts antioxidant 1010, 0.3 parts magnesium stearate as a lubricant, 2.2 parts polyethylene glycol PEG6000 as a pore-forming agent, and calcium carbonate with a particle size of 6μm.

[0042] Hot melt adhesive: The amount was adjusted to 18% of the meltblown fabric mass, and the rest was the same as in Example 1;

[0043] Sound insulation board substrate: completely consistent with Example 1.

[0044] Process step adjustments:

[0045] Only the parameters of the hot melt bonding step are adjusted; the remaining steps are the same as in Example 1.

[0046] Hot melt bonding: The hot melt adhesive is evenly spread on the uneven surface of the meltblown fabric of the concave-convex boundary layer, and then placed on the sound insulation board and put into the hot melt bonding machine. Set the bonding temperature to 135℃, the preheating time to 30s, the first bonding pressure to 0.15MPa and hold for 15s, the second bonding pressure to 0.45MPa and hold for 20s, and the bonding speed to 1.8m / min to complete the hot melt bonding.

[0047] Example 3:

[0048] The specific plan is as follows:

[0049] Raw material ratio adjustment:

[0050] Raw materials for the textured boundary layer meltblown fabric: 88 parts polypropylene, 10 parts silica (textile-forming agent), 0.6 parts antioxidant 1076, 0.4 parts zinc stearate (lubricant), 1.8 parts polypropylene glycol PPG4000 (pore-forming agent), silica particle size 5μm;

[0051] Hot melt adhesive: Replace with 100 parts of polyolefin hot melt adhesive POE, melting point 100℃, the amount used is 16% of the mass of meltblown fabric;

[0052] Sound insulation board substrate: density adjusted to 220kg / m³ 3 The rest is the same as in Example 2.

[0053] Process step adjustments:

[0054] Based on the adjustment of raw material type, the parameters of meltblown fabric preparation and hot melt bonding steps were finely adjusted, while the remaining steps were the same as in Example 2:

[0055] Meltblown fabric preparation: The extrusion temperature was adjusted to 205℃, the spinning pressure to 0.35MPa, and the cooling wind speed to 3.5m / s. The remaining parameters were the same as in Example 2. A textured boundary layer meltblown fabric with a thickness of 2mm and a texture height of 0.4mm was prepared.

[0056] Hot melt bonding: The bonding temperature is adjusted to 120℃, the bonding pressure of the first stage is 0.2MPa and held for 12s, the bonding pressure of the second stage is 0.4MPa and held for 25s, the bonding speed is 2m / min, and the other parameters are the same as in Example 2.

[0057] Example 4:

[0058] Raw material ratio:

[0059] The proportions of each raw material by weight are as follows:

[0060] Raw materials for the textured surface layer meltblown fabric: 89 parts polypropylene, 11 parts calcium carbonate and silica composite system (1:1 mass ratio) for texture forming agent, 0.6 parts antioxidant 1010 and 1076 composite system (2:1 mass ratio), 0.4 parts lubricant magnesium stearate and zinc stearate composite system (3:1 mass ratio), 2.0 parts pore-forming agent polyethylene glycol PEG6000 and polypropylene glycol PPG4000 composite system (1:1 mass ratio), calcium carbonate particle size 6μm, silica particle size 5μm;

[0061] Hot melt adhesive: 100 parts of EVA and POE composite system with a mass ratio of 2:1, EVA with 28% VA content, POE with a melting point of 105℃, and the amount used during bonding is 17% of the meltblown fabric mass;

[0062] Sound insulation board substrate: Polyester fiber sound insulation board, density 270kg / m³ 3 Thickness 11mm, porosity 78%.

[0063] Process steps:

[0064] Preparation of textured boundary layer meltblown fabric: The raw materials were mixed evenly according to the formula and fed into a twin-screw extruder. The extrusion temperature was set to 215℃, the screw speed to 310r / min, and after melt mixing for 3min, the fabric was spun through a gradient micro-orifice spinneret with a spinneret orifice diameter of 0.3mm, a spinneret pressure of 0.32MPa, a cooling air velocity of 3.2m / s, a receiving distance of 16cm, and a winding speed of 5.5m / min, to obtain a textured boundary layer meltblown fabric with a thickness of 2.2mm and a texture height of 0.45mm.

[0065] Pretreatment of sound insulation boards: Place the polyester fiber sound insulation boards into a forced-air drying oven and dry at 82℃ for 2.2 hours to remove surface moisture and impurities. After removal, allow them to cool naturally to room temperature for later use.

[0066] Hot melt bonding: Hot melt adhesive is evenly spread on the uneven surface of the meltblown fabric of the concave-convex boundary layer, and after being stacked with the sound insulation board, it is placed into the hot melt bonding machine. The bonding temperature is set to 132℃, the preheating time is 32s, the first bonding pressure is 0.18MPa and the pressure is held for 13s, the second bonding pressure is 0.42MPa and the pressure is held for 22s, and the bonding speed is 1.9m / min to complete the hot melt bonding.

[0067] Post-processing: After bonding, the composite board is placed in a constant temperature and humidity chamber at 26℃ and 52% humidity for 26 hours. After removal, the final composite structure of the concave-convex boundary layer meltblown fabric sound insulation board is obtained.

[0068] Comparative Example 1:

[0069] This comparative example uses an existing mature process for bonding planar meltblown fabric to sound insulation panels, but does not employ the concave-convex boundary layer structure and corresponding optimized parameters of this invention.

[0070] Specific method: The raw material of meltblown fabric is only 99.8 parts of polypropylene and 0.2 parts of antioxidant 1010, without the formation agent of uneven structure and pore-forming agent, and a planar meltblown fabric with a thickness of 2mm is prepared; the hot melt adhesive, sound insulation board substrate and bonding process steps are completely consistent with those in Example 1.

[0071] Comparative Example 2:

[0072] This comparative example uses a conventional hot melt bonding process and does not employ the segmented pressure control technology of this invention.

[0073] Specific procedures: The raw material ratio, meltblown fabric preparation, sound insulation board pretreatment, and post-treatment steps are completely consistent with those in Example 1; the hot melt bonding step uses a single pressure of 0.3 MPa and holds the pressure for 30 seconds, without segmented pressure control, and the bonding temperature and speed are consistent with those in Example 1.

[0074] Comparative Example 3:

[0075] This comparative example represents an unoptimized raw material ratio scheme in the prior art, and the amount of the uneven structure forming agent exceeds the protection scope of this invention.

[0076] Specific scheme: The amount of calcium carbonate as the concave-convex structure forming agent in the concave-convex boundary layer meltblown fabric is 25 parts, the amount of polypropylene is adjusted to 73.5 parts, and the proportions of the remaining raw materials are the same as in Example 1; the preparation of meltblown fabric, pretreatment of sound insulation board, hot melt bonding, and post-treatment steps are all completely the same as in Example 1.

[0077] Comparative Example 4:

[0078] This comparative example illustrates a solution in the prior art where the selection and dosage of hot melt adhesive are not adapted to the characteristics of the substrate.

[0079] Specific solution: hot melt adhesive is replaced with polyurethane (PU) hot melt adhesive with a melting point of 180°C and a dosage of 8% of the meltblown fabric mass. The bonding temperature is adjusted to 180°C. The remaining raw material ratios, meltblown fabric preparation, sound insulation board pretreatment, and post-treatment steps are completely consistent with those in Example 1.

[0080] Comparative Example 5:

[0081] This comparative example illustrates a bonding process in the prior art that omits the substrate pretreatment step.

[0082] Specific solution: The undried sound insulation board is directly heat-fused to the meltblown fabric; the remaining raw material ratios, meltblown fabric preparation, heat-fusion bonding, and post-processing steps are completely consistent with those in Example 1.

[0083] Comparative Example 6:

[0084] This comparative example is a simple superposition of the existing meltblown fabric bonding process and the existing sound insulation board processing process, without any collaborative optimization design.

[0085] Specific solution: The existing conventional planar meltblown fabric preparation process is adopted, which is the same as Comparative Example 1. The existing polyester fiber sound insulation board processing process only involves cutting and shaping without pretreatment. When bonding, the existing single pressure hot melt bonding process is directly adopted, which is the same as Comparative Example 2. All raw materials and parameters are directly used in the two existing processes without any optimization or adjustment.

[0086] Performance testing:

[0087] Test sample:

[0088] The composite boards prepared in Examples 1 to 4 and Comparative Examples 1 to 6 were cut into samples according to the requirements of each test standard. Each sample was tested in parallel 3 times, and the average value was taken as the final test result to ensure the accuracy and reliability of the test data.

[0089] The test items and standards are as follows: Table 1:

[0090]

[0091] The test results are shown in Table 2 below:

[0092]

[0093] The following analysis can be obtained from Table 2 above:

[0094] Compared with Comparative Example 1, the technical solution of this invention differs in many aspects in terms of technical means. This invention incorporates a texture-forming agent and a pore-forming agent, employs a gradient structure design for the meltblown fabric, optimizes the synergistic ratio between raw materials, and utilizes a segmented hot-melt bonding process. Test data shows that the application of these technical means improves the bonding strength of the composite board, with an increase ranging from 36.3% to 66.7%, and also improves noise reduction, with an increase ranging from 27.7% to 43.3%, helping to address the difficulty in simultaneously achieving sound insulation and bonding strength in existing technologies.

[0095] Compared with Comparative Examples 2 to 5, this invention has made targeted adjustments and optimizations to relevant core aspects. Test results show that the bonding strength of this invention is improved by 36.3% to 122.8%, the moisture resistance retention rate is improved by 9.3% to 19.1%, and the unevenness height retention rate is improved by 13.5% to 27.6%. This indicates that through multi-dimensional adjustments and coordination, the technical solution of this invention can better guarantee the various related properties of the composite board.

[0096] Compared to Comparative Example 6, which directly utilizes existing meltblown fabric lamination and sound insulation board processing technologies without additional adjustments, the technical solution of this invention focuses on the compatibility between the two, making corresponding adjustments and improvements to relevant processes. This results in an increase in lamination strength of 56.8% to 73.7% and an increase in noise reduction of 30.6% to 46.5%, further enhancing the overall performance of the composite board.

[0097] The performance changes in each embodiment exhibit a consistent optimization trend, from basic molding effects to enhanced structural stability, then to optimized aging resistance, ultimately achieving an overall performance improvement, forming a complete performance optimization framework. This trend confirms the rationality and feasibility of the technical solution of this invention, and can help those skilled in the art to better understand and apply this invention.

[0098] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A process for hot-melt bonding of a textured surface layer meltblown fabric to a sound insulation board, characterized in that, Includes the following steps: (1) Preparation of uneven boundary layer meltblown fabric: Polypropylene, uneven structure forming agent, antioxidant, lubricant and pore forming agent are mixed evenly, put into a twin screw extruder for melt mixing, and then spun through a gradient micro-hole spinneret. After cooling, receiving and winding, uneven boundary layer meltblown fabric is obtained. (2) Pretreatment of sound insulation board: Place the sound insulation board substrate in a forced-air drying oven to dry it, remove surface moisture and impurities, and then let it cool naturally to room temperature. (3) Hot melt bonding: The hot melt adhesive is evenly spread on the uneven surface of the meltblown fabric of the uneven surface layer, and then stacked with the pre-treated sound insulation board and placed into the hot melt bonding machine. After preheating, segmented pressure bonding is adopted, and the first stage pressure holding and the second stage pressure holding are carried out in sequence to complete the hot melt bonding. (4) Post-processing: The laminated composite board is placed in a constant temperature and humidity chamber for curing. After being taken out, the composite structure of the convex and concave surface layer meltblown cloth sound insulation board is obtained. In the raw material of the uneven surface layer meltblown fabric, the uneven structure forming agent is calcium carbonate, silicon dioxide or a composite system of the two, the antioxidant is 1010, 1076 or a composite system of the two, the lubricant is magnesium stearate, zinc stearate or a composite system of the two, and the pore-forming agent is polyethylene glycol, polypropylene glycol or a composite system of the two. In step (3), the preheating time is 30 to 32 seconds, the bonding temperature is 120 to 140°C, the bonding pressure of the first stage is 0.15 to 0.2 MPa, and the holding time is 10 to 15 seconds; the bonding pressure of the second stage is 0.4 to 0.45 MPa, and the holding time is 20 to 25 seconds; the bonding speed is 1.8 to 2 m / min.

2. The process according to claim 1, characterized in that, The hot melt adhesive is an ethylene-vinyl acetate copolymer, a polyolefin hot melt adhesive, or a composite system of both.

3. The process according to claim 1, characterized in that, The sound insulation board substrate is a polyester fiber sound insulation board with a porosity of not less than 75%.

4. The process according to claim 1, characterized in that, In step (1), the extrusion temperature of the twin-screw extruder is 205 to 215°C, the screw speed is 300 to 310 r / min, the melt mixing time is 3 min, the spinneret pressure is 0.3 to 0.35 MPa, the cooling air velocity is 3 to 3.5 m / s, the receiving distance is 15 to 16 cm, and the winding speed is 5 to 5.5 m / min.

5. The process according to claim 1, characterized in that, In step (2), the drying temperature of the blower drying oven is 78 to 85°C and the drying time is 2 to 2.5 hours.

6. The process according to claim 1, characterized in that, In step (4), the temperature of the constant temperature and humidity chamber is 25 to 26°C, the humidity is 50 to 52%, and the curing time is 24 to 26 hours.

7. The process according to claim 1, characterized in that, When the texture-forming agent is a composite system of calcium carbonate and silica, the mass ratio of the two is 1:1; when the antioxidant is a composite system of 1010 and 1076, the mass ratio of the two is 2:1; when the lubricant is a composite system of magnesium stearate and zinc stearate, the mass ratio of the two is 3:1; and when the pore-forming agent is a composite system of polyethylene glycol and polypropylene glycol, the mass ratio of the two is 1:

1.

8. The process according to claim 2, characterized in that, When the hot melt adhesive is a composite system of ethylene vinyl acetate copolymer and polyolefin hot melt adhesive, the mass ratio of the two is 2:1.

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