A process for modifying the surface of a nonwoven fabric for automotive interiors to be hydrophobic and slip resistant

Abstract

The application relates to the technical field of textile surface treatment, and discloses a hydrophobic and antiskid surface modification process for non-woven fabric of automobile interior decoration. The process comprises the following steps: introducing sacrificial micron-sized particles in fiber mixing and performing needle punching reinforcement; constructing a macroscopic directional micro-groove array on the surface by using a heat calendering device; forming micron-sized holes in situ by peeling off the particles through a sacrificial template method; and finally, impregnating and solidifying modification by using a low-surface-energy finishing liquid. The application realizes the deep integration of efficient water rolling and mechanical antiskid under high load, and the micro-nano structure has high mechanical stability and weather resistance due to the skeleton shielding effect.

Description

Technical Field

[0001] This invention belongs to the field of textile surface treatment technology, specifically relating to a hydrophobic and anti-slip surface modification process for automotive interior nonwoven fabrics. Background Technology

[0002] Currently, the mainstream technical approach for hydrophobic treatment of automotive interior nonwoven fabrics mainly relies on low surface energy chemical modification, which involves impregnation, spraying, or plasma treatment with fluorocarbon resins or organosiloxane coatings to form an extremely thin low-energy molecular film on the fiber surface.

[0003] Traditional hydrophobic agents, while reducing fiber surface energy and increasing the hydrophobic angle, inevitably fill in the tiny physical irregularities between fibers, making the material surface microscopically smooth. This smoothing objectively and significantly reduces the surface friction coefficient of the material. Especially when interior surfaces are wet or have residual moisture, the low surface energy coating not only fails to provide the necessary damping but also causes a sharp drop in friction due to the lubricating effect of the micron-sized film formed by moisture, leading to serious slippage. For critical areas such as car carpets and around pedals, this hydrophobic but non-slip characteristic greatly increases the risk of slipping when occupants enter and exit, creating a safety hazard.

[0004] Meanwhile, in pursuing higher levels of superhydrophobic properties (i.e., high contact angle and low roll-off angle in the Cassie state), existing technologies often rely heavily on constructing extremely fine and complex micro- and nano-scale rough structures on the material surface. Although such structures can utilize the air cushion effect to achieve excellent water droplet roll-off performance, their inherent physical stability is exceptionally fragile.

[0005] In automotive interiors, where there is high-frequency mechanical friction, foot traffic, and foreign object compression, micro- and nano-protrusions lacking macroscopic framework protection are highly susceptible to mechanical fracture, wear, or clogging by micro-dust. Once these delicate micro- and nano-structures are damaged, the material surface rapidly collapses from a superhydrophobic Cassie state to a highly adhesive Wenzel state, resulting in a precipitous drop in hydrophobic properties. Furthermore, due to the irreversibility of the structural damage, the modified layer will completely fail within a short period of time. Summary of the Invention

[0006] This invention aims to solve the technical bottlenecks of existing automotive interior nonwoven fabrics after hydrophobic modification, which are generally characterized by the mutual incompatibility of hydrophobic and anti-slip properties and the lack of mechanical stability of superhydrophobic micro-nano structures, thereby providing a hydrophobic and anti-slip surface modification process for automotive interior nonwoven fabrics.

[0007] To achieve the above objectives, this invention provides a hydrophobic and anti-slip surface modification process for automotive interior nonwoven fabrics. The core technical approach lies in the collaborative construction of multi-level structures at the macro, micro, and nano scales, embedding a high-mechanical-strength anti-slip skeleton into the nonwoven fiber network system, and combining this with the sacrificial template method to derive highly stable hydrophobic micropores. Finally, low surface energy chemical modification is applied to achieve a deep integration of efficient water roll-off and mechanical anti-slip under high loads.

[0008] The present invention provides a process for modifying the hydrophobic and anti-slip surface of nonwoven fabric for automotive interiors, and the specific process flow and technical parameters are as follows.

[0009] In the fiber formulation and mixing stage of the nonwoven fabric substrate, this process uses a physical blend of a first matrix fiber and a second bonding fiber. The first matrix fiber is made of polyethylene terephthalate (PET) fiber, with a single filament fineness controlled between 1.5 denier and 3.0 denier, and a cut length of 38 mm to 51 mm. The first matrix fiber serves as the main load-bearing component, ensuring the macroscopic mechanical strength of the nonwoven fabric. The second bonding fiber is made of core-sheath structure low-melting-point polyester fiber, with a core melting point of 250°C to 260°C and a sheath melting point of 110°C to 130°C, and a single filament fineness of 2.0 denier to 4.0 denier. During the mixing process, the mass ratio of the first matrix fiber to the second bonding fiber is set to 70:30 to 85:15. Based on this, sacrificial micron-sized particles, accounting for 5% to 15% of the total fiber mass, are uniformly introduced into the fiber blending system. The sacrificial micron-sized particles are selected from anhydrous sodium sulfate or calcium carbonate particles, with a normally distributed particle diameter and a median particle size (D50) controlled between 20 and 50 micrometers. To ensure uniform dispersion of the sacrificial micron-sized particles in the fiber network and to prevent them from falling off during subsequent web-forming processes, the particle surface is pretreated before mixing by coating the particle surface with a titanate coupling agent at a mass fraction of 1% to 3% to enhance the physical adhesion between the particles and the polyester fiber surface.

[0010] In the nonwoven fabric web formation and reinforcement stage, a carding machine is used to construct a uniform fiber web from the mixed fibers and particles, which then proceeds to the needle punching reinforcement process. The needle punching process combines pre-needling and main needle punching. The pre-needling frequency is set to 200 to 400 times per minute, with a penetration depth of 8 to 12 millimeters. The main needle punching process uses double-sided needles, with a needle density controlled at 200 to 500 needles per square centimeter. Through the reciprocating motion of the needles, the sacrificial micron-sized particles are deeply embedded in the physical nodes formed by the fiber intersections, creating a micropore preset point with a three-dimensional spatial distribution.

[0011] In the integrated molding stage of the three-dimensional anti-slip texture on the surface, the nonwoven fabric reinforced by needle punching enters the hot calendering equipment. The hot calendering equipment is equipped with a set of metal engraving rollers and flattening rollers with specific geometric topologies. The surface of the metal engraving rollers is engraved with a continuous array of directional microgrooves. These directional microgrooves have an inverted isosceles trapezoidal or V-shaped structure in cross-section, with a groove depth set to 100 to 300 micrometers, a groove width of 200 to 500 micrometers, and a spacing between adjacent grooves set to 300 to 600 micrometers. During the hot pressing process, the surface temperature of the engraving rollers is set to 140 to 160 degrees Celsius, a temperature range higher than the melting point of the second bonded fiber sheath but lower than the melting point of its core layer and the first matrix fiber. The calendering pressure is set to 5 to 15 MPa, and the production line speed is controlled at 5 to 15 meters per minute. Under the combined effects of high temperature and high pressure, the fibers on the surface of the nonwoven fabric undergo localized melting and rearrangement, forming a macroscopic array of oriented microgrooves and microprotrusions that perfectly match the pattern of the engraving roller. This macroscopic texture design mimics the drainage and gripping principles of tire tread patterns, enabling effective mechanical interlocking with contact objects such as shoe sole rubber, thereby providing sufficient frictional damping in wet environments.

[0012] In a preferred embodiment of the present invention, after hot calendering, the nonwoven fabric undergoes a micro / nano structure peeling triggering treatment to remove the aforementioned implanted sacrificial micron-sized particles. The formed nonwoven fabric is continuously immersed in a deionized water bath or dilute acid solution bath at a temperature of 40°C to 60°C, supplemented by ultrasonic oscillation at a frequency of 20 kHz to 40 kHz. During the water bath process, the anhydrous sodium sulfate or calcium carbonate particles embedded in the fiber nodes and surface layer dissolve and peel off, leaving a large number of micron-sized pores with irregular morphologies in situ. These micron-sized pores, superimposed with the macroscopic grooves formed by hot pressing, constitute a rough skeleton with hierarchical characteristics. Because these pores are formed by the disappearance of particles after occupying space, their edges are anchored by partially melted adhesive fibers, thus possessing extremely high structural stability and not easily collapsing under mechanical wear.

[0013] After constructing the micro / nano framework, the nonwoven fabric enters the chemical modification stage of its superhydrophobic surface. This process employs a composite low surface energy finishing solution, composed of a long-chain perfluoroalkyl silane coupling agent, nano-sized silica dispersion, anhydrous ethanol, and a catalyst. The long-chain perfluoroalkyl silane coupling agent is selected from trichloro(1H,1H,2H,2H-perfluorooctyl)silane or perfluorodecyltriethoxysilane, with a mass percentage concentration of 2% to 5%. The nano-sized silica particles have a particle size of 20 to 50 nanometers and their surface is modified with silanization to ensure high dispersion in the ethanol solvent; their addition amount accounts for 0.5% to 1.5% of the total mass of the finishing solution. The pH of the finishing solution is adjusted to 4.5 to 5.5 using glacial acetic acid to promote the hydrolysis of silane monomers.

[0014] The modification process employs a continuous impregnation-drying-curing operation. First, the nonwoven fabric with a layered structure is completely immersed in the finishing solution for 3 to 10 minutes, with the liquid content adjusted by a rolling mill to maintain between 60% and 80%. Next, the nonwoven fabric enters a pre-drying zone to remove the solvent at 80 to 90 degrees Celsius. Finally, it enters a high-temperature curing zone at 150 to 170 degrees Celsius for 5 to 15 minutes. During high-temperature curing, the hydrolysis products of the silane coupling agent, silanol groups, undergo a condensation reaction with the hydroxyl or carboxyl groups on the surface of the nonwoven fibers, forming covalent bonds. Simultaneously, nano-silica particles are firmly anchored to the inner walls of micron-sized pores and the protruding parts of macro-grooves, forming a third-level nano-rough structure. Ultimately, a biomimetic composite coating with ultra-low surface energy was constructed on the surface of the nonwoven fabric, with a water droplet contact angle that can be stably maintained between 150 and 165 degrees and a roll-off angle of less than 8 degrees.

[0015] The surface constructed by the process of this invention exhibits both technological advantages and physical properties. On a macroscopic scale, the directional microgrooves formed by hot calendering serve as the first-level structure, primarily providing mechanical anti-slip properties. When an external object undergoes relative displacement with the nonwoven fabric surface, the sidewalls of the microgrooves provide normal resistance. Especially in the presence of moisture, the microgrooves act as miniature drainage channels, effectively disrupting any potential continuous lubricating water film and maintaining the static friction coefficient of the interface.

[0016] At the micro and nanoscale, the micropores formed by the sacrificial template method and the deposited nanoparticles together constitute the second and third level of rough structures. This hierarchical structure can effectively trap air, forming a stable thin layer of air, i.e., the Cassie-Baxter state. When a water droplet comes into contact with the surface, due to the support of the air pad, the water droplet only contacts the tip of the micro / nano structure, greatly reducing the solid-liquid contact area, thus exhibiting extremely high hydrophobicity and extremely low adhesion.

[0017] More importantly, this invention solves the mechanical stability problem of superhydrophobic structures through a skeleton protection mechanism. Since the nanoscale hydrophobic structure is constructed within micron-sized pores and on the slopes and bottoms of macroscopic grooves, when the nonwoven fabric is subjected to external abrasion (such as stepping or scratching), the mechanical load is mainly borne by the macroscopic micro-protrusions and the high-strength polyester fiber skeleton. The micro-nano structures located in the recessed areas and inside the pores are physically shielded, avoiding direct contact with the abrasive medium, thus maintaining excellent hydrophobic properties even during long-term mechanical cycling.

[0018] The process described in this invention also exhibits a high degree of certainty in chemical modification. Due to the use of a covalently bonded silanization reaction, the low surface energy molecular layer and the fiber substrate are not simply physically adsorbed, but rather form a strong chemical bond. This ensures that the modified layer will not migrate or peel off after repeated exposure to high temperatures, low temperatures, and chemical cleaning, thus meeting the weather resistance requirements of automotive interior materials.

[0019] To address the stringent controls on volatile organic compound (VOC) emissions in automotive interiors, this process incorporates a highly efficient solvent recovery and condensation system during the solvent removal stage. Anhydrous ethanol evaporated during pre-drying is liquefied and recovered by a circulating fan in the condenser, reducing environmental impact and safety risks during production. The cured nonwoven fabric surface is free of any free small-molecule fluorosilicone monomers. Third-party testing shows that its levels of volatile substances such as benzene, toluene, and xylene are far below automotive industry standards.

[0020] As a supplementary detail of the present invention, the arrangement direction of the directional microgrooves can be adjusted according to the specific application area of ​​the automotive interior. For example, when the nonwoven fabric is used for the car driver's seat carpet, the extension direction of the microgrooves is set to be perpendicular to the vehicle's direction of travel to provide maximum front-to-back anti-slip resistance; when used for the door inner panel, the microgrooves are distributed in a cross-grid pattern to balance omnidirectional stain-resistant self-cleaning capability and tactile comfort.

[0021] In the above process, to meet the lightweight requirements of nonwoven fabrics, by precisely controlling the ratio of the first matrix fiber to the second bonding fiber, the areal density of the nonwoven fabric can be controlled at 200 to 600 grams per square meter without sacrificing strength. This lightweight structure, combined with the surface modification of this invention, enables the final product to maintain excellent physical properties while helping to reduce the overall vehicle weight and improve fuel economy.

[0022] Furthermore, the modification process described in this invention has excellent compatibility. Besides polyester nonwovens, for nonwovens made of materials such as polypropylene and polyamide, similar hydrophobic and anti-slip composite effects can be achieved simply by fine-tuning the hot-calendering temperature parameters based on the differences in fiber melting points (e.g., adjusting the hot-calendering temperature of polypropylene nonwovens to 130°C to 145°C) and adjusting the type of silane coupling agent in the finishing solution (e.g., using silanes containing specific functional groups to match the active sites on different polymer surfaces).

[0023] In practical engineering implementation, to further enhance the self-cleaning ability of the surface, the nano-silica particles in the finishing solution can be partially replaced with nano-titanium dioxide particles, with a replacement ratio of 20% to 40%. Nano-titanium dioxide exhibits photocatalytic activity under sunlight or ultraviolet light irradiation inside a vehicle, and can decompose trace amounts of organic pollutants deposited in the micropores of the superhydrophobic surface, thereby achieving dual protection of structural antifouling and chemical self-cleaning.

[0024] The process of this invention improves the retention of the original color and feel of the fiber. Since the modified layer is mainly concentrated on the fiber surface and in the shallow pores, and the fluorosilicone molecular chain segments have good flexibility, the modified nonwoven fabric still retains its original soft touch and color fastness.

[0025] The hydrophobic and anti-slip surface modification process for automotive interior nonwoven fabrics described in this invention not only reconstructs the physicochemical properties of the material at the microscale, but also enhances the overall safety performance of automotive interiors at the macroscopic engineering application level. This integrated structure-function-durability design represents the cutting-edge trend in contemporary high-performance functional textile research and development, possessing extremely high commercial application value and social benefits.

[0026] To ensure process stability and repeatability, the conductivity of the deionized water bath needs to be monitored in real time on the actual production line, ensuring it remains below 10 microsiemens / cm to prevent impurity ions in the water from interfering with the directional alignment of the silane coupling agent on the fiber surface. Simultaneously, the pressure distribution unevenness of the hot-pressing rollers must be controlled within ±3% to guarantee the consistency of the anti-slip texture across the entire width of the nonwoven fabric. These precise engineering control parameters, together with the aforementioned core process steps, constitute the complete technical system of this invention.

[0027] In the technical solution of this invention, the anisotropic design of the directional microgrooves is key to improving anti-slip efficiency. Experiments have shown that when an object slides perpendicular to the groove direction, its frictional force is more than 2.5 times that when sliding parallel to the groove direction. This anisotropic characteristic allows engineers to customize production based on the force characteristics of different locations within the vehicle.

[0028] Compared with the prior art, the beneficial effects of the present invention are: This invention resolves the conflict between hydrophobicity and anti-slip properties, as well as functionality and durability, by introducing sacrificial particles during the fiber web formation stage, constructing macroscopic anti-slip textures through integrated hot calendering during the molding stage, triggering micro-nano pores using a sacrificial template method during the processing stage, and finally achieving surface low-energy through an efficient silanization reaction. This process is clear and the parameters are precisely controlled, not only improving the safety and functionality of automotive interiors but also providing a novel, large-scale industrially feasible technical solution for the surface engineering modification of high-performance composite materials. Detailed Implementation

[0029] This invention provides a process for modifying the hydrophobic and anti-slip surface of nonwoven fabrics for automotive interiors. The primary step lies in the preparation of fiber substrates for specific applications in automotive interiors. In the fiber formulation stage, this process strictly selects a first matrix fiber with high modulus and excellent thermal stability, specifically polyethylene terephthalate (PET) fiber. The single filament fineness of this fiber is precisely controlled between 1.5 denier and 3.0 denier. This fineness range ensures that the nonwoven fabric has sufficient porosity macroscopically to accommodate subsequent modification components. Simultaneously, the cutting length is set to 38 mm to 51 mm to ensure that the fibers can fully interweave during the subsequent carding process, forming a stable three-dimensional force-bearing network. The second bonding fiber, as an auxiliary component, uses a core-sheath structure of low-melting-point polyester fiber. Its core layer is composed of high-molecular-weight polyester with a melting point of 250°C to 260°C, providing support; the sheath layer is composed of copolyester with a melting point of 110°C to 130°C. The monofilament fineness of the second bonding fiber is set to 2.0 denier to 4.0 denier. In terms of the specific mixing ratio, the mass ratio of the first matrix fiber to the second bonding fiber is adjusted between 70:30 and 85:15 according to the stiffness requirements of the final product.

[0030] The technical solution of the present invention will be described in detail below with reference to specific embodiments and comparative examples, so as to ensure that those skilled in the art can fully understand and implement the present invention.

[0031] Example 1: The first matrix fiber is polyethylene terephthalate fiber (monofilament fineness 2.2 denier, cut length 45 mm), and the second bonding fiber is core-sheath structure low melting point polyester fiber (core melting point 255 degrees Celsius, sheath melting point 120 degrees Celsius, monofilament fineness 3.0 denier), with a mass ratio of 78:22. The sacrificial micron-sized particles are anhydrous sodium sulfate (D50 35 microns, accounting for 10% of the total fiber mass), pretreated with 2% titanate coupling agent; The composite low surface energy finishing solution contains 3% long-chain perfluoroalkyl silane coupling agent, 1.0% nano silica particles (particle size 35 nm), and anhydrous ethanol as solvent, with a pH value of 5.0. The surface density of the non-woven fabric is 400 grams per square meter; Preparation steps: S1: Fiber blending and particle implantation, the first matrix fiber, the second bonding fiber and the pretreated sacrificial micron-sized particles are mixed and uniformly dispersed to form a mixed fiber component; S2: Web formation and needle punching reinforcement, combing and mixing fiber components to form a fiber web, pre-needling frequency of 300 times per minute and penetration depth of 10 mm; main needle punching adopts double-sided layout, needle density of 350 needles per square centimeter, embedding particles deep into fiber nodes. S3: Macroscopic anti-slip texture hot pressing molding, the non-woven fabric is fed into the hot calendering equipment, the surface temperature of the metal engraving roller is 150 degrees Celsius, the calendering pressure is 10 MPa, the production line speed is 10 meters per minute, the microgrooves of the engraving roller are inverted isosceles trapezoids (depth 200 micrometers, groove width 350 micrometers, spacing 450 micrometers), forming an array of directional microgrooves and microprotrusions; S4: Cascaded microporous structure peeling trigger, the non-woven fabric after hot pressing is immersed in a 50-degree deionized water bath, and 30 kHz ultrasonic oscillation assists in peeling off particles. The conductivity is monitored in real time and maintained below 10 micro Siemens per centimeter, forming a rough skeleton with superimposed micron-level pores and macro-grooves. S5: Superhydrophobic surface chemical modification, the non-woven fabric is immersed in the composite low surface energy finishing liquid for 6 minutes, the liquid rate is adjusted to 70% by the rolling mill; the solvent is removed by pre-drying at 85 degrees Celsius, the solvent recovery rate is 96%; and it is cured at 160 degrees Celsius for 10 minutes to form a three-level hierarchical biomimetic composite superhydrophobic coating.

[0032] Example 2: The mass ratio of the first matrix fiber to the second adhesive fiber is 70:30, and the remaining components and proportions are the same as in Example 1; Preparation steps: Same as in Example 1.

[0033] Example 3: The mass ratio of the first matrix fiber to the second adhesive fiber is 85:15, and the remaining components and proportions are the same as in Example 1; Preparation steps: Same as in Example 1.

[0034] Example 4: The amount of sacrificial micron-sized particles added accounts for 5% of the total fiber mass, and the remaining components and proportions are the same as in Example 1; Preparation steps: Same as in Example 1.

[0035] Example 5: The amount of sacrificial micron-sized particles added accounts for 15% of the total fiber mass, and the remaining components and proportions are the same as in Example 1; Preparation steps: Same as in Example 1.

[0036] Example 6: Same as Example 1; Preparation steps: The surface temperature of the metal engraving roller is 140 degrees Celsius during the hot rolling forming stage, and the remaining steps are the same as in Example 1.

[0037] Example 7: Same as Example 1; Preparation steps: The surface temperature of the metal engraving roller is 160 degrees Celsius during the hot rolling forming stage, and the remaining steps are the same as in Example 1.

[0038] Example 8: 40% of the nano-silica particles in the composite low surface energy finishing liquid were replaced with nano-titanium dioxide particles, and the remaining components and proportions were the same as in Example 1; Preparation steps: Same as in Example 1.

[0039] Comparative Example 1: The sacrificial micron-sized particles were removed, and the remaining components were the same as in Example 1; Preparation steps: The particle implantation and peeling triggering steps are omitted, and the remaining process parameters and steps are the same as in Example 1.

[0040] Comparative Example 2: The remaining components are the same as in Example 1; Preparation steps: The flat roller hot pressing is used to replace the metal engraving roller, and there is no macroscopic microgroove forming. The remaining process parameters and steps are the same as in Example 1.

[0041] Test method: Hydrophobicity test: The contact angle and roll-off angle of the water droplet were measured using a contact angle measuring instrument; Anti-slip performance test: The wet static friction coefficient was measured using a friction coefficient measuring instrument, and the improvement ratio was compared with that before modification; Self-cleaning performance test: Spray simulated pollutants, rinse with water and evaluate the pollutant residue rate; Mechanical abrasion resistance test: The Martindale abrasion tester was used to rub the surface for 1000 cycles under a load of 9 kPa, and the change rate of contact angle after abrasion resistance was measured. Structural stability test: After 50 bending and rubbing cycles, observe the integrity of the surface micro-nano structure and the change in contact angle; Air permeability test: The air permeability per unit area per unit time is measured using an air permeability meter.

[0042] The test data comparisons are shown in Table 1 and Table 2.

[0043] Table 1. Comparison of water droplet contact angle, roll-off angle, wet static friction coefficient, and contact angle after 1000 wear cycles. Table 2 Comparison of Contact Angle Change Rate, Contaminant Residue Rate, and Air Permeability Examples 1 to 8 utilize macroscopic microgrooves formed by hot calendering to provide a mechanical anti-slip foundation, micron-sized pores created by the sacrificial template method to construct a rough framework, and nanoparticles introduced by a low surface energy finishing liquid to form a superhydrophobic surface layer. These three elements synergistically achieve a deep integration of hydrophobicity and anti-slip properties. Comparative Example 1, lacking sacrificial micron-sized particles and a microporous structure, exhibits significantly reduced hydrophobicity and wear resistance. Comparative Example 2, lacking macroscopic microgrooving, has a low wet friction coefficient and poor anti-slip effect.

[0044] When the mass ratio of the first matrix fiber to the second bonding fiber is 78:22 to 85:15, the particle addition is 10% to 15%, and the hot calendering temperature is 150°C to 160°C, the water droplet contact angle is larger, the roll-off angle is smaller, and the wet static friction coefficient is higher. Among these factors, the particle addition directly affects the micropore density and roughness, while the hot calendering temperature determines the macro-groove forming quality and fiber bonding effect. The two work together to ensure a balance between hydrophobic and anti-slip properties.

[0045] Compared to Comparative Example 1 without sacrificial particles, the water droplet contact angle of the embodiment is increased by more than 17%, the wet static friction coefficient is increased by more than 76%, and the contact angle change rate after wear is reduced by more than 79%; compared to Comparative Example 2 without macrogrooves, the water droplet contact angle is increased by more than 8%, the wet static friction coefficient is increased by more than 63%, the contaminant residue rate is reduced by more than 72%, while maintaining good breathability and soft feel.

[0046] In summary, this invention achieves simultaneous improvement in hydrophobicity and anti-slip properties through the synergistic construction of a three-level structure coupled with low surface energy chemical modification. It also exhibits excellent mechanical stability and weather resistance, meeting the stringent requirements of automotive interiors and possessing good potential for industrialization.

[0047] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for modifying the hydrophobic and anti-slip surface of nonwoven fabric for automotive interiors, characterized in that, Includes the following steps: Fiber blending and particle implantation; Networking and needle reinforcement; Integrated hot-press molding of macroscopic anti-slip texture; The peeling of cascaded microporous structures is triggered. Chemical modification of superhydrophobic surfaces using tertiary nanostructures.

2. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 1, characterized in that, The fiber blending and particle implantation involves blending a first matrix fiber with a second adhesive fiber having a core-sheath structure, introducing surface-pretreated sacrificial micron-sized particles, and obtaining a mixed fiber component containing pre-embedded micropore generation sites.

3. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 2, characterized in that, The web formation and needle-punching reinforcement process utilizes a carding process to construct a uniformly distributed fiber web from the mixed fiber components. Through continuous reinforcement processes of pre-needling and main needle-punching, the fibers are highly entangled in three-dimensional space. The reciprocating motion of the needles deeply embeds the sacrificial micron-sized particles into the physical nodes formed by the fiber intersections, thus constructing micropore preset points with three-dimensional spatial distribution characteristics.

4. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 3, characterized in that, The integrated hot-pressing molding of the macroscopic anti-slip texture involves feeding the needle-punched and reinforced nonwoven fabric into a hot-pressing equipment equipped with a metal engraving roller. Through high temperature and high pressure, an array of directional microgrooves and microprotrusions that complement the engraving roller pattern is formed on the macroscopic surface of the nonwoven fabric.

5. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 4, characterized in that, The peeling trigger of the cascaded microporous structure involves immersing the thermo-pressed nonwoven fabric in a deionized water bath or a dilute acid solution bath, and then using ultrasound to dissolve and peel off the sacrificial micron-sized particles embedded in the fiber nodes and surface, leaving micron-sized pores with irregular geometric morphology and anchored by molten bonded fibers in situ.

6. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 5, characterized in that, The three-level nanostructure chemical modification of the superhydrophobic surface involves preparing a composite low surface energy finishing liquid containing a long-chain perfluoroalkyl silane coupling agent and nano-sized silica particles. Through an impregnation-drying-curing process, the silanol groups generated by the hydrolysis of the silane coupling agent undergo a condensation reaction with the active groups on the fiber surface to form covalent bonds. At the same time, the nano-sized silica particles are anchored to the inner walls of the micron-sized pores and the surface of the macroscopic oriented microgrooves, thus constructing a biomimetic composite superhydrophobic coating with a macro-micro-nano three-level hierarchical structure on the nonwoven fabric surface.

7. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 2, characterized in that, The first matrix fiber is polyethylene terephthalate fiber; the second adhesive fiber is a core-sheath structure low-melting-point polyester fiber; the mass ratio of the first matrix fiber to the second adhesive fiber is set to 70:30 to 85:

15.

8. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 2, characterized in that, The amount of sacrificial micron-sized particles added accounts for 5% to 15% of the total fiber mass; the sacrificial micron-sized particles are selected from anhydrous sodium sulfate or calcium carbonate particles; before mixing, the surface of the sacrificial micron-sized particles is pretreated by coating with a titanate coupling agent with a mass fraction of 1% to 3%.

9. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 3, characterized in that, The frequency of the pre-needling process is set to 200 to 400 times per minute, and the insertion depth is 8 to 12 millimeters; the main acupuncture process adopts a double-sided needle layout, and the needle density is controlled at 200 to 500 needles per square centimeter.

10. The process for modifying the hydrophobic and anti-slip surface of automotive interior nonwoven fabric according to claim 4, characterized in that, The directional microgrooves engraved on the surface of the metal engraving roller have an inverted isosceles trapezoidal or V-shaped structure in cross-section. The groove depth of the directional microgroove is set to 100 micrometers to 300 micrometers, the groove width is set to 200 micrometers to 500 micrometers, and the spacing between adjacent grooves is set to 300 micrometers to 600 micrometers.

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