Lightweight automotive carpet and production method thereof

Abstract

The invention discloses a light-weight automobile carpet and a production method thereof, and belongs to the field of automobile carpets, the light-weight automobile carpet comprises a fabric layer, a bonding / blocking layer and a bottom felt layer from top to bottom, and the light-weight automobile carpet is prepared from the following raw materials in parts by weight: 32-38 parts of the fabric layer, 10-14 parts of the bonding / blocking layer and 45-55 parts of the bottom felt layer. According to the application, a lightweight synergistic system constructed by the hollow glass beads and the SiO2-based aerogel powder is matched with the entanglement design of a needling process on fiber and powder raw materials, so that the dependence of a traditional carpet on a heavy coating HL is eliminated; a multi-dimensional function synergistic promotion system is constructed, and through adsorption and purification synergy of modified zeolite powder and microencapsulated tea polyphenol, wear-resistant protection synergy of polytetrafluoroethylene micro powder and nano SiO2, long-acting bacteriostatic action of a silver ion antibacterial agent, halogen-free flame retardant function of magnesium hydroxide micro powder and acoustic enhancement characteristic of SiO2-based aerogel powder, the wear-resistant and flame-retardant performance of the nano SiO2-based aerogel powder is improved. Comprehensive optimization of VOC control, bacteriostasis, flame retardance, wear resistance and sound absorption performance is realized.

Description

Technical Field

[0001] This application belongs to the field of automotive carpets, and specifically relates to a lightweight automotive carpet and its manufacturing method. Background Technology

[0002] The automotive industry's demand for lightweighting and fuel economy continues to rise. As a core interior component, automotive carpets must simultaneously meet requirements for acoustic performance, foot comfort, and aesthetics. Current automotive carpets generally employ a composite structure consisting of tufted or needle-punched fabric, PE, HL heavy-duty coating, and barrier film or non-woven fabric. The HL heavy-duty coating is a key component for structural support and interlayer adhesion, but it accounts for the largest proportion and weight of the overall structure, resulting in a high carpet weight, which contradicts the trend towards automotive lightweighting. To adapt to lightweighting requirements, the industry primarily optimizes the carpet by reducing the weight of the HL heavy-duty coating. However, the lightweighting effect is limited, and it is difficult to maintain the original performance of the carpet while reducing weight.

[0003] Current automotive carpet structures are highly dependent on the HL heavy-duty coating, leading to an irreconcilable conflict between lightweighting and structural stability. Specifically, reducing the basis weight of the HL heavy-duty coating to achieve weight reduction directly results in insufficient carpet rigidity, which in turn causes problems such as poor fit to the vehicle body structure during assembly, uneven peripheral gaps, and unstable matching. This seriously affects the carpet's performance and the overall vehicle assembly quality, becoming an industry bottleneck restricting the lightweighting development of automotive carpets. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a lightweight automotive carpet and its manufacturing method, which offers advantages such as reduced carpet weight, maintained carpet structural rigidity, low VOC content, antibacterial properties, flame retardancy, and sound absorption.

[0005] In a first aspect, embodiments of this application provide a lightweight automotive carpet, comprising, from top to bottom, a fabric layer, an adhesive / barrier layer, and a backing layer, made from the following raw materials in parts by weight: Fabric layer 32-38 parts: The fabric layer includes 24-28 parts of tufted PET fabric or needle-punched PET fabric, 3-5 parts of water-based polyurethane coating, 0.8-1.2 parts of polytetrafluoroethylene micro powder, 0.7-1.1 parts of nano silica, and 0.5-0.7 parts of microencapsulated tea polyphenols; 10-14 parts of adhesive / barrier layer: The adhesive / barrier layer includes 3-4 parts of PE powder, 1.5-2.5 parts of PET powder, 0.5-0.8 parts of maleic anhydride-grafted PE compatibilizer, 0.1-0.2 parts of antioxidant, 0.1-0.2 parts of UV-P type benzotriazole ultraviolet absorber, and 4.8-5.3 parts of PA / EVOH co-extruded film barrier film substrate; 45-55 parts of base mat layer: The base mat layer includes 18-22 parts of modified PET fiber, 12-15 parts of PP fiber, 3-5 parts of cotton and linen mixed fiber, 2.5-3.5 parts of hollow glass microspheres, 1.5-2.5 parts of SiO2-based aerogel powder, 2-3 parts of modified zeolite powder activated by hydrochloric acid, 4-6 parts of magnesium hydroxide micropowder with a particle size of 1-5 μm, 0.4-0.6 parts of silver-loaded zeolite-type silver ion antibacterial agent, 1.2-1.8 parts of ethylene-octene copolymer toughening agent, and 0.4-0.6 parts of maleic anhydride-grafted polypropylene.

[0006] Optionally, the mass ratio of PE powder to PET powder in the adhesive / barrier layer is 1.5:1 to 2.5:1; the antioxidant is a compound of type 1010 hindered phenolic antioxidant and type 168 phosphite antioxidant in a mass ratio of 1:1 to 1.5.

[0007] Optionally, the mass ratio of modified PET fiber to PP fiber in the base layer is 1.2:1 to 1.8:1.

[0008] Secondly, embodiments of this application provide a method for producing lightweight automotive carpets, comprising the following steps: S1: Raw material pretreatment: Microencapsulated tea polyphenols, hollow glass microspheres, SiO2-based aerogel powder, and modified zeolite powder are passed through a 100-120 mesh sieve, and the sieve-passing material is collected for later use; modified PET fiber, PP fiber, and cotton-linen blended fiber are dried at 80-100℃ for 1-2 hours, and the moisture content is controlled to be ≤1.5%; S2: Preparation of the base felt: Weigh the modified PET fiber, PP fiber, cotton and linen mixed fiber, hollow glass microspheres, SiO2-based aerogel powder, modified zeolite powder, magnesium hydroxide micro powder, silver ion antibacterial agent, ethylene-octene copolymer toughening agent, and maleic anhydride grafted polypropylene according to the weight proportions after pretreatment in step S1. After carding, web laying, and needle punching into felt, send it into a forced-air drying oven at 130-220℃ for heating and shaping. The length of the oven is 20-50m to obtain the base felt. S3: Fabric pretreatment: Weigh out tufted PET fabric or needle-punched PET fabric by weight, coat the back of the fabric with water-based polyurethane coating, and then dry it in an oven at 130-180℃. S4: Composite molding: The base felt and the PA / EVOH co-extruded barrier film substrate are fed into a heating device at 110-220°C. Pre-treated PE powder, PET powder, maleic anhydride-grafted PE compatibilizer, antioxidant, and UV absorber are sprinkled on the surface of the barrier film substrate. Then, it is composited with the fabric pre-treated in step S3. The speed of the heating device is 3-10 m / min, and the differential speed ratio between each conveyor roller is ≤1.1. After exiting the oven, it is pressed by the pressing roller. S5: Post-processing and molding: After cooling, cutting, brushing and trimming the composite blank obtained in step S4, it is heated and softened and then sent to a molding press for molding. After cooling, accessory installation and water cutting processes, lightweight automotive carpet is obtained.

[0009] Optionally, in step S1, the modified PET fiber, PP fiber, and cotton-linen blended fiber are dried using hot air circulation with a hot air velocity of 0.5–1 m / s; the microencapsulated tea polyphenols and hollow glass microspheres are dried at 50–60°C for 30–60 min after sieving.

[0010] Optionally, in step S2, the heating and setting time is 3-5 minutes, and the hardness of the base felt after setting is Shore D hardness 35-45HD; the needle-punching depth of the felt is 8-12 mm, and the needle-punching density is 150-200 needles / cm. 2 .

[0011] Optionally, in step S3, the waterborne polyurethane coating is applied using a doctor blade, with a coating thickness of 0.1–0.3 mm and a coating amount of 30–50 g / m². 2 The oven uses a top-and-bottom opposing blower, with the lower blower frequency being 1.2 to 2 times the speed of the upper blower, and the drying time being 2 to 4 minutes.

[0012] Optionally, in step S4, the pressing pressure of the pressing roller is 0.8 to 1.5 MPa, the pressing temperature is 80 to 120°C, and the gap between the pressing rollers is 0.3 to 0.6 times the sum of the thickness of the fabric and the base felt.

[0013] Optionally, in step S4, the heating equipment adopts a conveyor belt or a conveyor belt with hanging pins, and the tension of the conveyor belt is controlled at 50-80 N / m; if it is not necessary to coat the powdered polymer, a heating roller can be used to heat the barrier film, with the heating roller temperature at 160-220℃, the speed at 6-20 m / min, and the bonding pressure between the heating roller and the base felt at 0.3-0.5 MPa.

[0014] Optionally, in step S5, the composite blank is cooled by a combination of water cooling and air cooling. First, it is cooled to 40-50°C by spraying with cooling water at 15-25°C, and then the surface moisture is dried by blowing with warm air. After molding, it needs to be foamed. The foaming temperature is 140-160°C and the foaming time is 1-2 minutes.

[0015] Compared with the prior art, this application has the following advantages: 1. A lightweight synergistic system constructed by hollow glass microspheres and SiO2-based aerogel powder, combined with the entanglement design of fiber and powder raw materials by needle punching process, is used from the two aspects of material formulation and molding process to get rid of the dependence of traditional carpets on heavy-duty HL coating: traditional carpet weight reduction is often accompanied by problems such as insufficient rigidity and unstable matching. In this application, hollow glass microspheres and SiO2-based aerogel powder play the advantage of low density to achieve the weight reduction target, while needle punching process strengthens the entanglement effect between raw materials, so that the base felt maintains appropriate rigidity and ensures that the carpet fits the vehicle body structure and the surrounding gaps are uniform when assembled. This effectively breaks through the bottleneck of traditional carpets that it is difficult to balance lightweight and structural stability. 2. Construct a multi-dimensional functional synergistic enhancement system. Through the synergistic adsorption and purification of modified zeolite powder and microencapsulated tea polyphenols, the synergistic wear resistance and protection of polytetrafluoroethylene micropowder and nano-SiO2, the long-lasting antibacterial effect of silver ion antibacterial agent, the halogen-free flame retardant function of magnesium hydroxide micropowder, and the acoustic enhancement properties of SiO2-based aerogel powder, the system achieves comprehensive optimization of VOC control, antibacterial, flame retardant, wear resistance, and sound absorption performance. Modified zeolite powder adsorbs harmful gases, microencapsulated tea polyphenols optimize the odor environment, polytetrafluoroethylene micropowder and nano-SiO2 form a protective layer on the fabric surface to extend service life, silver ion antibacterial agent inhibits bacterial growth, magnesium hydroxide micropowder improves safety, and SiO2-based aerogel powder improves the in-vehicle acoustic experience, breaking through the limitations of traditional carpets that are single-function and cannot meet multi-dimensional usage needs. 3. By employing a scientific synergistic combination of natural modified components and conventional industrial raw materials, and replacing some expensive chemical additives with natural modified components, the cost of raw material procurement can be effectively controlled while ensuring the overall performance of the product. Precise control and optimization of the process and pretreatment reduce the scrap rate caused by raw material agglomeration and poor interlayer adhesion, thereby reducing production losses. At the same time, the introduction of natural components reduces the use and release risks of chemical substances, and reduces VOC emissions during carpet production and use, which is in line with the green and environmentally friendly development trend of automotive interior materials, and balances the economic benefits of enterprises with social and environmental benefits.

[0016] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart illustrating a method for producing lightweight automotive carpets is shown. Figure 2 The following charts show a comparison of the gram weights of Examples 1-12 and Comparative Examples 1-5; Figure 3 The Shore D hardness comparison charts of Examples 1 to 12 and Comparative Examples 1 to 5 are shown; Figure 4 The following charts show the formaldehyde comparison between Examples 1-12 and Comparative Examples 1-5; Figure 5 The accompanying diagram shows a comparison of acetaldehyde in Examples 1-12 and Comparative Examples 1-5. Figure 6 The following diagrams show a comparison of TVOC between Examples 1-12 and Comparative Examples 1-5; Figure 7 A comparison chart of odor levels between Examples 1 to 12 and Comparative Examples 1 to 5 is shown; Figure 8 A comparison chart of sound absorption coefficients of Examples 1 to 12 and Comparative Examples 1 to 5 is shown; Figure 9 A comparison chart of the number of wear resistance cycles of Examples 1 to 12 and Comparative Examples 1 to 5 is shown; Figure 10 A comparison chart of antibacterial rates between Examples 1 to 12 and Comparative Examples 1 to 5 is shown; Figure 11 A comparison chart of oxygen indexes for Examples 1 to 12 and Comparative Examples 1 to 5 is shown. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] Traditional automotive carpets have the following problems in production and application: First, they rely on heavy-duty HL coatings (EVA / POE / EPDM, etc.) for structural support and adhesion, resulting in a carpet weight of 2500–6000 g / m². Even if the HL weight is reduced to 1000–2000 g / m², the problem persists. 2First, it still fails to meet the demands of lightweighting and fuel economy in automobiles. Second, after weight reduction, HL is prone to problems such as being too soft, having unstable matching, and large gaps around the edges, making it difficult to balance rigidity and molding adaptability. Third, the additives and material monomers added during HL production can easily lead to excessive levels of VOCs such as formaldehyde, acetaldehyde, and styrene, with a high odor level, affecting the air quality inside the vehicle. Fourth, the traditional structure has limited sound absorption performance, especially in the high-frequency noise scenarios of pure electric vehicles, making it unsuitable for such environments. Fifth, the fabric lacks wear resistance and stain resistance, and the base felt lacks antibacterial and flame-retardant properties, making it prone to wear and bacterial growth with long-term use, and it lacks flame-retardant protection. Sixth, the uneven dispersion of raw materials and poor interlayer bonding stability in the production process result in large performance fluctuations between batches, making it difficult to adapt to the needs of continuous industrial production.

[0021] To address the aforementioned pain points of existing technologies, this application provides a lightweight automotive carpet and its production method. By designing a layered composite structure of fabric layer—adhesive / barrier layer—backing felt, and using a ratio of basic raw materials such as tufted PET fabric and modified PET fibers, combined with lightweight components such as hollow glass microspheres and SiO2-based aerogel powder, functional additives such as modified zeolite powder and microencapsulated tea polyphenols, and modifying components such as maleic anhydride grafted compatibilizers and ethylene-octene copolymer toughening agents, a process system of raw material pretreatment, layered preparation, and precise compounding is designed. This not only solves the pain points of traditional carpets being heavy and having poor compatibility, but also improves comprehensive performance such as VOC control, sound absorption, wear resistance, antibacterial properties, and flame retardancy through synergistic material effects. Furthermore, optimized process parameters ensure batch stability, adapting to the needs of automotive interior use.

[0022] In this embodiment, regarding the raw material ratio, the fabric layer uses 24-28 parts of tufted PET fabric or needle-punched PET fabric as the base material, combined with 3-5 parts of water-based polyurethane adhesive to improve adhesion, 1-2.5 parts of polytetrafluoroethylene micro powder and 1-3 parts of nano-silica to synergistically improve wear resistance and stain resistance, and 0.5-0.7 parts of microencapsulated tea polyphenols to achieve odor adsorption and antibacterial properties; the adhesive / barrier layer uses 3-4 parts of PE powder and 1.5-2.5 parts of PET powder as the core adhesive components, balancing adhesive strength and formability at a mass ratio of 1.5:1 to 2.5:1, combined with 0.5-0.8 parts of maleic anhydride-grafted PE compatibilizer to improve interlayer interface bonding, 0.1-0.2 parts of type 1010 hindered phenolic antioxidant and type 168 phosphite antioxidant (compounded at a mass ratio of 1:1 to 1.5) to improve thermal stability, and 0.1 ~0.2 parts of UV-P type benzotriazole ultraviolet absorber delay aging; 4.8-5.3 parts of PA / EVOH co-extruded film ensure barrier performance; the base layer uses 18-22 parts of modified PET fiber and 12-15 parts of PP fiber as the base material (mass ratio 1.2:1-1.8:1), combined with 3-5 parts of cotton and linen blended fiber to enhance comfort; 2.5-3.5 parts of hollow glass microspheres and 1.5-2.5 parts of SiO2-based aerogel powder to achieve lightweighting and sound absorption enhancement; 2-3 parts of modified zeolite powder activated by hydrochloric acid to adsorb VOCs; 4-6 parts of magnesium hydroxide micropowder to provide halogen-free flame retardancy; 0.4-0.6 parts of silver-loaded zeolite-type silver ion antibacterial agent to achieve long-lasting antibacterial effect; 1.2-1.8 parts of ethylene-octene copolymer toughening agent and 0.4-0.6 parts of maleic anhydride grafted polypropylene to improve rigidity and adhesion.

[0023] In terms of process, the embodiments of this application adopt a process of raw material graded pretreatment, step-by-step preparation of base felt and fabric, and temperature-controlled composite, which not only ensures uniform dispersion of raw materials and stable interlayer adhesion, but also further reduces VOCs through multi-stage heating treatment to ensure that the overall performance meets the standards.

[0024] As attached Figure 1 As shown, the complete process steps of this application are as follows: S1: Raw material pretreatment Microencapsulated tea polyphenols, hollow glass microspheres, SiO2-based aerogel powder, and modified zeolite powder were sieved through a 100-120 mesh sieve, and the sieved material was collected for later use. Modified PET fiber, PP fiber, and cotton-linen blended fiber were dried at 80-100℃ using hot air circulation for 1-2 hours with a hot air velocity of 0.5-1 m / s, and the moisture content was controlled to be ≤1.5%. After sieving, microencapsulated tea polyphenols and hollow glass microspheres were dried at 50-60℃ for 30-60 minutes to prevent moisture absorption and clumping.

[0025] In some embodiments of this application, in step S1, the fiber drying using a hot air circulation method can ensure uniform drying and avoid poor interlayer adhesion caused by local moisture residue; the drying temperature of 50-60℃ can remove moisture from the surface of the powder raw material and prevent the microencapsulated tea polyphenols from breaking due to excessive temperature, ensuring their odor adsorption function; if the drying temperature is below 50℃, the moisture removal is incomplete, and bubbles are easily generated in the subsequent compounding process; if it is above 60℃, the capsule wall of the microcapsule is easily damaged, causing the tea polyphenols to be released prematurely and become ineffective.

[0026] In some embodiments of this application, in step S1, the modified zeolite powder needs to be activated at 100-110°C for 1 hour before sieving to further increase the specific surface area and enhance the VOC adsorption capacity; the hollow glass microspheres need to be sealed and stored after sieving to prevent moisture and agglomeration from affecting the lightweight effect.

[0027] S2: Preparation of base felt Weigh out the modified PET fiber, PP fiber, cotton-linen blended fiber, hollow glass microspheres, SiO2-based aerogel powder, modified zeolite powder, magnesium hydroxide micro powder, silver ion antibacterial agent, ethylene-octene copolymer toughening agent, and maleic anhydride-grafted polypropylene pretreated in step S1 according to the specified weight proportions. After carding and web formation, the fibers are laid at a density of 150–200 needles / cm. 2 The needle-punching density and needle-punching depth of 8-12 mm are used to needle-punch the felt, and then the felt is heated and shaped in a forced-air drying oven at 130-220℃ for 3-5 minutes. The length of the drying oven is 20-50m, and a base felt with a Shore D hardness of 35-45HD is obtained.

[0028] In some embodiments of this application, in step S2, 150-200 stitches / cm 2 The needle-punching density and needle-punching depth of 8-12mm ensure that the fibers and powder raw materials are tightly entangled, preventing the base felt from becoming loose; the heating and setting time of 3-5min and the temperature range of 130-220℃ can release the internal stress of the fibers, promote fiber adhesion, and improve the rigidity of the base felt: if the setting temperature is below 130℃, the fiber adhesion is insufficient and the base felt is too soft; if it is above 220℃, the fibers are prone to aging and embrittlement, affecting the service life; the design of Shore D hardness of 35-45HD can balance rigidity and comfort and avoid gaps during matching.

[0029] In some embodiments of this application, in step S2, a double doffer carding machine is used for the carding and web laying process to ensure uniform fiber distribution; the web laying thickness is controlled to be 2-4 mm to reserve space for subsequent composite molding.

[0030] S3: Fabric Pretreatment Weigh out tufted PET fabric or needle-punched PET fabric according to the specified weight percentages, and apply water-based polyurethane coating to the back of the fabric using a scraper coating method. The coating thickness is 0.1–0.3 mm, and the coating amount is 30–50 g / m².2 Then, it is placed in an oven at 130-180℃ and dried for 2-4 minutes. The oven uses an upper and lower counter-blowing blower, with the lower blower frequency being 1.2-2 times the speed of the upper blower, to ensure that the glue curing rate is ≥90%.

[0031] In some embodiments of this application, in step S3, the scraper coating can precisely control the amount of adhesive applied, avoiding differences in abrasion resistance caused by uneven adhesive application; the coating thickness of 0.1 to 0.3 mm can ensure the bonding strength without increasing the weight due to excessive adhesive application; the design of the top and bottom blowing blowers can accelerate the drying of the adhesive, and the lower blower frequency is higher than the upper blower to avoid adhesive residue on the back of the fabric and ensure uniform drying; if the drying time is less than 2 minutes, the adhesive will not be completely cured and the layers will easily peel off; if it is longer than 4 minutes, the fabric will easily shrink and deform, affecting dimensional accuracy.

[0032] S4: Composite Molding The base felt and the PA / EVOH co-extruded barrier film substrate are fed together into a heating device at 110-220°C. The heating device uses a mesh belt or a mesh belt with hanging pins for conveying, and the mesh belt tension is controlled at 50-80 N / m. Pretreated PE powder, PET powder, maleic anhydride-grafted PE compatibilizer, antioxidant, and UV absorber are sprinkled on the surface of the barrier film substrate, and then it is compounded with the fabric pretreated in step S3. The speed of the heating device is 3-10 m / min, and the differential speed ratio between each conveying roller is ≤1.1. After exiting the oven, it is pressed by pressing rollers at a pressure of 0.8-1.5 MPa and a pressing temperature of 80-120°C. The gap between the pressing rollers is 0.3-0.6 times the sum of the thickness of the fabric and the base felt.

[0033] In some embodiments of this application, in step S4, controlling the belt tension to 50-80 N / m can prevent stretching deformation of the base felt and barrier film during transport; a speed of 3-10 m / min and a heating temperature of 110-220°C can ensure that the powder binder is fully melted and achieves tight interlayer bonding; if the speed is too fast, the binder will not melt sufficiently and the bonding strength will be insufficient; if it is too slow, the raw material is prone to overheating and aging; the coordinated design of pressing pressure and temperature can further improve the interlayer bonding force, and the control of the gap between pressing rollers can ensure that the composite blank thickness is uniform with a deviation of ≤±0.1 mm.

[0034] In some embodiments of this application, in step S4, if it is not necessary to sprinkle powdered polymer, a heating roller can be used to heat the barrier film. The temperature of the heating roller is 160-220°C, the speed is 6-20m / min, and the bonding pressure between the heating roller and the base felt is 0.3-0.5MPa to ensure the adhesion effect between the barrier film and the base felt.

[0035] S5: Post-processing and molding The composite blank obtained in step S4 is cooled using a combination of water cooling and air cooling. First, it is cooled to 40-50°C by spraying with cooling water at 15-25°C, and then the surface moisture is dried by blowing warm air. It is then cut using a CNC cutting machine with a cutting accuracy of ±0.5mm. After brushing and trimming, it is heated and softened before being sent to a molding machine for molding. The molding temperature is 120-160°C, the molding pressure is 1.5-3MPa, and the holding time is 2-4min. After molding, it is foamed at 140-160°C for 1-2min, with the foaming ratio controlled at 1.2-1.5 times. After cooling, accessory installation (the edges of the carpet are polished before installation with a polishing accuracy of ±0.2mm), and water-cutting process, a lightweight automotive carpet is obtained.

[0036] In some embodiments of this application, in step S5, the combination of water cooling and air cooling can quickly and evenly reduce the temperature, preventing the composite blank from cracking due to excessively fast cooling or sticking due to excessively slow cooling; CNC cutting and edge grinding can ensure that the carpet size and the molding die are accurately matched, avoiding installation gaps; the coordinated design of molding parameters and foaming treatment can further improve the carpet forming accuracy and sound absorption performance: if the foaming ratio is less than 1.2 times, the sound absorption effect is insufficient; if it is greater than 1.5 times, the carpet structural strength decreases.

[0037] The lightweight automotive carpet and its production method of this application are described in detail below with reference to specific embodiments. The raw materials in each embodiment meet the aforementioned proportion range and specification requirements, and the process steps refer to the aforementioned complete process steps. Only some parameters are different. The total weight of the raw materials in each embodiment is 100 parts.

[0038] Example 1 The lightweight automotive carpet and its production method provided in this embodiment include the following specific steps: S1: Raw material pretreatment: 0.6 parts of microencapsulated tea polyphenols, 3 parts of hollow glass microspheres, 2 parts of SiO2-based aerogel powder, and 2.5 parts of modified zeolite powder were passed through a 110-mesh sieve; the modified zeolite powder was activated at 105℃ for 1 hour; the microencapsulated tea polyphenols and hollow glass microspheres were dried at 55℃ for 45 minutes, with a moisture content ≤0.8%; 21 parts of modified PET fiber, 13 parts of PP fiber, and 4 parts of cotton-linen blended fiber were dried using hot air circulation at 90℃ for 1.5 hours with a hot air velocity of 0.8 m / s, with a moisture content ≤1.2%.

[0039] S2: Preparation of the base felt: Weigh out 21 parts of modified PET fiber, 13 parts of PP fiber, 4 parts of cotton and linen mixed fiber, 3 parts of hollow glass microspheres, 2 parts of SiO2-based aerogel powder, 2.5 parts of modified zeolite powder, 5 parts of magnesium hydroxide micro powder, 0.5 parts of silver-loaded zeolite-type silver ion antibacterial agent, 1.5 parts of ethylene-octene copolymer toughening agent, and 0.5 parts of maleic anhydride-grafted polypropylene according to the following weight proportions: carded and laid in a double-dough carding machine (thickness 3mm), and needle-punched into felt at a needle-punching density of 180 needles / cm² and a needle-punching depth of 10mm; heat-set in a 200℃ forced-air drying oven for 4min, with an oven length of 35m, to obtain a base felt with a Shore D hardness of 40HD.

[0040] S3: Fabric pretreatment: Weigh 27.5 parts of tufted PET fabric, 4.9 parts of water-based polyurethane adhesive, 1.0 part of polytetrafluoroethylene micro powder, 1.0 part of nano-silica, and 0.6 parts of microencapsulated tea polyphenols; apply water-based polyurethane adhesive to the back of the fabric using a scraper coating method, with a coating thickness of 0.2 mm and a coating amount of 40 g / m²; dry in an oven at 150℃ for 3 minutes, with an upper and lower blower in the oven, the lower blower frequency being 1.5 times the speed of the upper blower, and the adhesive curing rate ≥95%.

[0041] S4: Composite Molding: 5.3 parts of the base felt and PA / EVOH co-extruded barrier film substrate are fed together into a heating device at 180℃, using a mesh belt conveyor with a tension of 65 N / m. 3.7 parts of PE powder, 2 parts of PET powder, 0.6 parts of maleic anhydride-grafted PE compatibilizer, 0.15 parts of type 1010 hindered phenolic antioxidant, 0.1 parts of type 168 phosphite antioxidant (mass ratio 1:1), and 0.15 parts of UV-P type benzotriazole ultraviolet absorber are sprinkled onto the barrier film surface. This is then combined with the pre-treated fabric. The heating device speed is 6 m / min, and the differential speed ratio between each conveyor roller is 1.05. After exiting the oven, the film is pressed by pressing rollers at a pressure of 1.2 MPa and a temperature of 100℃. The gap between the pressing rollers is 0.45 times the sum of the thicknesses of the fabric and the base felt.

[0042] S5: Post-processing and molding: The composite blank is first cooled to 45°C by spraying with 20°C cooling water, and then dried with room temperature air; it is cut by CNC cutting machine with an accuracy of ±0.3mm; after brushing and trimming, it is heated and softened, and then sent to the molding machine for molding at a molding temperature of 140°C, a pressure of 2MPa, and a holding time of 3min; after molding, it is foamed at 150°C for 1.5min with a foaming ratio of 1.3 times; after cooling, the edges of the carpet are polished (accuracy ±0.1mm), and auxiliary parts are installed and water-cutting process is performed to obtain a lightweight automotive carpet.

[0043] The manufacturers and models of the raw materials used in Example 1 are described below: Microencapsulated tea polyphenols: Hangzhou Lvtian Biotechnology, model LT-TP-01; Hollow glass microspheres: Qinhuangdao Shunchi New Materials, model SC-HGB-30; SiO2-based aerogel powder: Zhejiang Nanotech, model NT-AERO-01; Modified zeolite powder: Shandong Shouguang Zeolite Technology, model SG-ZS-03; Modified PET fiber: Yizheng Chemical Fiber, model PET-150D / 48F; PP fiber: Ningbo Formosa Plastics, model PP-1500; Cotton and linen blended fiber: Suzhou Huaye Textile, model CM-8020; Magnesium hydroxide micro powder: Shandong Haihua Group, model HH-MH-5; Silver-loaded zeolite-type silver ion antibacterial agent: Guangzhou Guangshi New Materials, model GS-Ag-03; Ethylene-octene copolymer toughening agent: Dow Chemical, model POE-8150; Maleic anhydride-grafted polypropylene: Shanghai Rizhisheng, model CMG9801; Tufted PET fabric: Changzhou Xurong Knitting, model XR-PET-280; Waterborne polyurethane coating: BASF, model Lupranate 2100; Polytetrafluoroethylene micro powder: DuPont, model MP1200; Nano-silica: Evonik Degussa, model AEROSIL 200; PA / EVOH co-extruded barrier film substrate: Shanghai Enjie New Materials, model EJ-PA / EVOH-05; PE powder: ExxonMobil, model LDPE 100AC; PET powder: DuPont, model PET-630; Maleic anhydride grafted PE compatibilizer: Nanjing Julong Technology, model JL-MAH-PE-01; Type 1010 hindered phenolic antioxidant: BASF, model Irganox 1010; Type 168 phosphite antioxidant: BASF, model Irganox 168; UV-P type benzotriazole ultraviolet absorber: Ciba Specialty Chemicals, model UV-P.

[0044] Examples 2-12, Comparative Examples 1-5 The preparation steps of Examples 2-12 and Comparative Examples 1-5 are based on Example 1. The baseline parameters include 3 parts hollow glass microspheres, 2 parts SiO2-based aerogel powder, 2.5 parts modified zeolite powder, 0.6 parts microencapsulated tea polyphenols, PE to PET powder mass ratio of 1.75:1, fiber drying temperature of 90℃, base mat shaping temperature of 200℃, and pressing pressure of 1.2MPa. Each example changes only one process parameter or raw material addition amount. The comparative examples omit key raw materials or use traditional processes. The specific differences are shown in Table 1. Comparative Example 1 omits hollow glass microspheres and SiO2-based aerogel powder; Comparative Example 2 omits modified zeolite powder and microencapsulated tea polyphenols; Comparative Example 3 omits polytetrafluoroethylene micropowder and nano-silica; Comparative Example 4 uses 15 parts of HL to replace the adhesive / barrier layer and part of the base felt material; Comparative Example 5 uses a traditional process (fibers are air-dried at room temperature, no powder pretreatment, and a pressing pressure of 0.5 MPa).

[0045] Table 1: Differences in parameters between the examples and comparative examples

[0046] The lightweight automotive carpets prepared in Examples 1-12 and Comparative Examples 1-5 were subjected to performance testing. The testing indicators and methods are as follows: Weight per unit area: Refer to GB / T 4669-2008 to test the weight per unit area of ​​the carpet; Shore D hardness: Refer to GB / T 2411-2008 to test the rigidity of the base felt after molding; VOC content: Refer to HJ / T 400-2007 to test the content of formaldehyde, acetaldehyde, and TVOC; Odor rating: Refer to the automotive industry odor bottle method (GB / T 27630-2011), with level 1 being the best and level 5 being the worst; Sound absorption coefficient: Refer to GB / T 20247-2006, and test the sound absorption performance at a frequency of 1000Hz; Abrasion resistance test: Refer to GB / T 250-2008 (Martindale method) to test abrasion resistance performance; Antibacterial rate: The antibacterial effect against Escherichia coli was tested according to GB / T 20944-2007; Oxygen index: Flame retardant performance was tested in accordance with GB / T 2406-2021.

[0047] The test results are shown in Table 2 and appendix. Figures 2 to 11 By combining the data in Tables 1 and 2, the influence of each parameter and raw material on performance can be derived.

[0048] Table 2: Performance Test Results of Examples and Comparative Examples

[0049] 1. Effect of the amount of hollow glass microspheres added (Comparison of Examples 1-3) Examples 2 (2.5 parts) and 3 (3.5 parts) differed only in the amount of hollow glass microspheres added; other parameters remained the same as in Example 1 (3 parts). Data showed that in Example 2, due to insufficient addition, the basis weight increased to 1580 g / m², and the Shore D hardness decreased to 38 HD, resulting in a decrease in both lightweight and rigidity. In Example 3, due to excessive addition, the basis weight decreased to 1320 g / m², and the hardness increased to 42 HD. However, excessive microspheres could lead to excessively large voids within the base felt, potentially affecting structural stability over long-term use. Example 1 (3 parts) represented the optimal addition amount, balancing lightweight (1450 g / m²) and rigidity (40 HD) without affecting other properties.

[0050] 2. Effect of SiO2-based aerogel powder addition amount (comparison of Examples 1, 4, and 5) Examples 4 (1.5 parts) and 5 (2.5 parts) only differed in the amount of SiO2-based aerogel powder added. In Example 4, due to insufficient addition, the sound absorption coefficient decreased to 0.64, and the lightweighting effect was weakened (weight 1520 g / m²). 2 In Example 5, excessive addition increased the sound absorption coefficient to 0.72 and reduced the weight to 1380 g / m², but significantly increased the cost; the addition of two parts in Example 1 achieved a balance between sound absorption performance (0.68) and lightweight (1450 g / m²). 2 Achieving a balance between cost and performance results in the best cost-effectiveness.

[0051] 3. Effect of modified zeolite powder addition amount (comparison of Examples 1, 6, and 7) Example 6 (2 samples): Due to insufficient modified zeolite powder, the content of formaldehyde, acetaldehyde, and TVOC increased to 25 ug / m³. 3 28ug / m 3 245ug / m 3 The odor level rose to 2.0; in Example 7 (3 portions), an excessive amount was added, and the VOC content was further reduced (formaldehyde 15ug / m³). 3 TVOC 195ug / m 3 Odor rating 1.0, but excessive zeolite powder can easily lead to a decrease in the breathability of the base felt; the addition of 2.5 parts in Example 1 can effectively control VOCs while ensuring the breathability and overall performance of the base felt.

[0052] 4. Effect of the amount of microencapsulated tea polyphenols added (Comparison of Examples 1, 8, and 9) In Example 8 (0.5 parts), the antibacterial rate dropped to 98.8% and the odor grade rose to 2.0 due to insufficient microencapsulated tea polyphenols. In Example 9 (0.7 parts), the antibacterial rate rose to 99.5% and the odor grade rose to 1.0 due to excessive addition, but the cost increased and there was no significant performance gain. The addition amount of 0.6 parts in Example 1 can achieve a balance between antibacterial (99.2%) and odor control (1.5 grade).

[0053] 5. Effect of PE to PET powder mass ratio (Comparison of Examples 1, 10, and 11) Example 10 (1.5:1) has insufficient bonding strength due to low PE powder content, resulting in a wear resistance of 34,500 cycles and a hardness of 39HD. Example 11 (2.5:1) has decreased flexibility of the composite blank due to excessive bonding caused by high PE powder content, but the wear resistance increased to 35,500 cycles. The 1.75:1 mass ratio of Example 1 can balance bonding strength and flexibility, with a wear resistance of 35,000 cycles and a hardness of 40HD, resulting in the best overall performance.

[0054] 6. Explanation of performance differences in special groups Example 12: Using process parameters of fiber drying temperature 80℃, base felt shaping temperature 180℃, and pressing pressure 1.0MPa, due to insufficient drying and insufficient pressing pressure, the formaldehyde content rose to 20ug / m³, the hardness was 38HD, and the abrasion resistance was 34200 times, which confirms the necessity of precise control of process parameters. Comparative Example 1: By omitting hollow glass microspheres and SiO2-based aerogel powder, the basis weight increased to 2150 g / m², and the sound absorption coefficient decreased to 0.52, completely losing the advantages of lightweight and acoustic properties, proving the core role of lightweight components; Comparative Example 2: Without modified zeolite powder and microencapsulated tea polyphenols, the levels of formaldehyde, acetaldehyde, and TVOC increased to 45 ug / m³. 3 38ug / m 3 320ug / m 3 With an odor rating of 3.5 and an antibacterial rate reduced to 95.0%, it highlights the role of VOC control and antibacterial ingredients. Comparative Example 3: By omitting polytetrafluoroethylene micro powder and nano silica, the number of wear-resistant cycles decreased to 28,000, demonstrating the importance of wear-resistant components in improving service life; Comparative Example 4: When the adhesive / barrier layer was replaced with HL, the basis weight increased to 2850 g / m², the VOC content significantly exceeded the standard, the oxygen index dropped to 26.0%, and the antibacterial rate was 90.0%, fully exposing the drawbacks of the traditional HL structure; Comparative Example 5: Using traditional processes (fiber air-drying at room temperature, no powder pretreatment, and pressing pressure of 0.5 MPa), the raw materials were unevenly dispersed and the interlayer adhesion was insufficient. The hardness was 36HD, the sound absorption coefficient was 0.60, and the abrasion resistance was 32,000 cycles, which confirms the advanced nature of the process optimization in this application.

[0055] The key performance of the lightweight automotive carpet prepared in Example 1 was compared with that of traditional HL-containing carpets. The results are shown in Table 3, demonstrating significant advantages: Table 3: Comparison of Performance of Material from Example 1 and Traditional HL-Containing Carpet

[0056] Data shows that: the material in Example 1, due to the synergistic effect of hollow glass microspheres and SiO2-based aerogel powder, reduces weight by 58.6% compared to traditional carpets, while increasing hardness by 5.3%, resolving the contradiction between lightweighting and compatibility; the synergistic effect of modified zeolite powder and microencapsulated tea polyphenols reduces formaldehyde content by 77.5%, TVOC by 35.2%, and improves odor level by 50.0%, improving in-vehicle air quality; the sound absorption coefficient is increased by 51.1%, making it suitable for high-frequency noise scenarios in pure electric vehicles; the synergistic effect of polytetrafluoroethylene micropowder and nano-silica increases wear resistance by 40.0%; the addition of silver ion antibacterial agent and magnesium hydroxide micropowder achieves an antibacterial rate of 99.2% and an oxygen index of 29.5%, expanding functional dimensions.

[0057] To ensure the repeatability of the process in actual production, the baseline parameters of Example 1 were subjected to three repeated tests to test the stability of key performance indicators. The results are shown in Table 4. The data shows that the coefficients of variation of indicators such as basis weight, hardness, formaldehyde, and sound absorption coefficient are all ≤1.0%, indicating that the process parameters are stable and reliable, avoiding the batch fluctuation problem of traditional processes and meeting the needs of continuous industrial production.

[0058] Table 4: Performance of Repeated Tests in Example 1

[0059] Based on Tables 1-4 and the performance analysis, the innovative points of this application regarding the lightweight automotive carpet and its production method can be summarized as follows: Innovative Raw Material Synergy System: A lightweight and multifunctional raw material synergy system is constructed. Hollow glass microspheres and SiO2-based aerogel powder work together to achieve a weight reduction of 58.6% while maintaining rigidity; modified zeolite powder and microencapsulated tea polyphenols work together to reduce VOCs and odor levels; polytetrafluoroethylene micropowder and nano-silica improve wear resistance; silver ion antibacterial agent and magnesium hydroxide micropowder expand antibacterial and flame-retardant functions, solving the drawbacks of traditional carpets' single-performance orientation.

[0060] Process optimization enhances molding stability: The design incorporates a graded pretreatment-step preparation-composite process system. Raw material pretreatment removes moisture and agglomerates, while layered preparation ensures that each layer meets functional standards. Temperature, pressure, and speed control in the composite process improves interlayer adhesion stability. The coefficient of variation in repeated tests is ≤3.0%, making it suitable for continuous industrial production and avoiding the problem of large batch fluctuations in traditional processes.

[0061] Expanding application scenarios and economic benefits: Lightweight design reduces vehicle energy consumption and improves fuel economy; low VOC and low odor levels meet the interior requirements of high-end models; antibacterial and flame-retardant functions expand the applicability to high-frequency use scenarios such as public transportation and ride-hailing; the production process does not require additional special equipment, the raw material cost is basically the same as that of traditional carpets, while reducing the scrap rate and comprehensively improving the economic benefits of enterprises.

[0062] In summary, the specific implementation method of this application demonstrates the innovation, stability and practicality of the technical solution through a complete logical chain of raw material innovation, process optimization and performance verification. It not only solves the pain points of traditional automotive carpets, such as heavy weight, poor compatibility, excessive VOCs and limited functionality, but also provides a new path for the lightweight and multifunctional development of automotive interior materials.

[0063] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A lightweight automotive carpet, comprising, from top to bottom, a fabric layer, an adhesive / barrier layer, and a backing felt layer, characterized in that, Made from the following parts by weight of raw materials: Fabric layer 32-38 parts: The fabric layer includes 24-28 parts of tufted PET fabric or needle-punched PET fabric, 3-5 parts of water-based polyurethane coating, 0.8-1.2 parts of polytetrafluoroethylene micro powder, 0.7-1.1 parts of nano-silica, and 0.5-0.7 parts of microencapsulated tea polyphenols; 10-14 parts of adhesive / barrier layer: The adhesive / barrier layer includes 3-4 parts of PE powder, 1.5-2.5 parts of PET powder, 0.5-0.8 parts of maleic anhydride-grafted PE compatibilizer, 0.1-0.2 parts of antioxidant, 0.1-0.2 parts of UV-P type benzotriazole ultraviolet absorber, and 4.8-5.3 parts of PA / EVOH co-extruded film barrier film substrate; 45-55 parts of the base felt layer: The base felt layer includes 18-22 parts of modified PET fiber, 12-15 parts of PP fiber, 3-5 parts of cotton and linen mixed fiber, 2.5-3.5 parts of hollow glass microspheres, 1.5-2.5 parts of SiO2-based aerogel powder, 2-3 parts of modified zeolite powder activated by hydrochloric acid, 4-6 parts of magnesium hydroxide micropowder with a particle size of 1-5 μm, 0.4-0.6 parts of silver-loaded zeolite-type silver ion antibacterial agent, 1.2-1.8 parts of ethylene-octene copolymer toughening agent, and 0.4-0.6 parts of maleic anhydride-grafted polypropylene.

2. The lightweight automotive carpet according to claim 1, characterized in that: The mass ratio of PE powder to PET powder in the adhesive / barrier layer is 1.5:1 to 2.5:1; the antioxidant is a compound of type 1010 hindered phenolic antioxidant and type 168 phosphite antioxidant in a mass ratio of 1:1 to 1.

5.

3. The lightweight automotive carpet according to claim 1, characterized in that: The mass ratio of modified PET fiber to PP fiber in the base felt layer is 1.2:1 to 1.8:

1.

4. A method for producing lightweight automotive carpets, characterized in that, The method for preparing the lightweight automotive carpet according to any one of claims 1 to 3 comprises the following steps: S1: Raw material pretreatment: Microencapsulated tea polyphenols, hollow glass microspheres, SiO2-based aerogel powder, and modified zeolite powder are passed through a 100-120 mesh sieve, and the sieve-passing material is collected for later use; modified PET fiber, PP fiber, and cotton-linen blended fiber are dried at 80-100℃ for 1-2 hours, and the moisture content is controlled to be ≤1.5%; S2: Preparation of the base felt: Weigh the modified PET fiber, PP fiber, cotton and linen mixed fiber, hollow glass microspheres, SiO2-based aerogel powder, modified zeolite powder, magnesium hydroxide micro powder, silver ion antibacterial agent, ethylene-octene copolymer toughening agent, and maleic anhydride grafted polypropylene according to the weight proportions after pretreatment in step S1. After carding, web laying, and needle punching into felt, send it into a forced-air drying oven at 130-220℃ for heating and shaping. The length of the oven is 20-50m to obtain the base felt. S3: Fabric pretreatment: Weigh out tufted PET fabric or needle-punched PET fabric by weight, coat the back of the fabric with water-based polyurethane coating, and then dry it in an oven at 130-180℃. S4: Composite molding: The base felt and the PA / EVOH co-extruded barrier film substrate are fed into a heating device at 110-220°C. Pre-treated PE powder, PET powder, maleic anhydride-grafted PE compatibilizer, antioxidant, and UV absorber are sprinkled on the surface of the barrier film substrate. Then, it is composited with the fabric pre-treated in step S3. The speed of the heating device is 3-10 m / min, and the differential speed ratio between each conveyor roller is ≤1.

1. After exiting the oven, it is pressed by the pressing roller. S5: Post-processing and molding: After cooling, cutting, brushing and trimming the composite blank obtained in step S4, it is heated and softened and then sent to a molding press for molding. After cooling, accessory installation and water cutting processes, lightweight automotive carpet is obtained.

5. The method for producing lightweight automotive carpets according to claim 4, characterized in that: In step S1, the modified PET fiber, PP fiber, and cotton-linen blended fiber are dried using hot air circulation with a hot air velocity of 0.5–1 m / s; the microencapsulated tea polyphenols and hollow glass microspheres are dried at 50–60°C for 30–60 min after sieving.

6. The method for producing lightweight automotive carpets according to claim 4, characterized in that: In step S2, the heating and setting time is 3-5 minutes, and the hardness of the base felt after setting is Shore D hardness 35-45HD; the needle-punching depth of the felt is 8-12 mm, and the needle-punching density is 150-200 needles / cm. 2 .

7. The method for producing lightweight automotive carpets according to claim 4, characterized in that: In step S3, the waterborne polyurethane adhesive is applied using a doctor blade, with a coating thickness of 0.1–0.3 mm and a coating amount of 30–50 g / m². 2 The oven uses a top-and-bottom opposing blower, with the lower blower frequency being 1.2 to 2 times the speed of the upper blower, and the drying time being 2 to 4 minutes.

8. The method for producing lightweight automotive carpets according to claim 4, characterized in that: In step S4, the pressing pressure of the pressing roller is 0.8 to 1.5 MPa, the pressing temperature is 80 to 120°C, and the gap between the pressing rollers is 0.3 to 0.6 times the sum of the thickness of the fabric and the base felt.

9. A method for producing lightweight automotive carpets according to claim 4, characterized in that: In step S4, the heating equipment uses a conveyor belt or a conveyor belt with hanging pins, and the tension of the conveyor belt is controlled at 50-80 N / m. If it is not necessary to spread powdered polymer, a heating roller can be used to heat the barrier film. The temperature of the heating roller is 160-220℃, the speed is 6-20 m / min, and the bonding pressure between the heating roller and the base felt is 0.3-0.5 MPa.

10. A method for producing lightweight automotive carpets according to claim 4, characterized in that: In step S5, the composite blank is cooled by a combination of water cooling and air cooling. First, it is cooled to 40-50°C by spraying with cooling water at 15-25°C, and then the surface moisture is dried by blowing with warm air. After molding, it needs to be foamed. The foaming temperature is 140-160°C and the foaming time is 1-2 minutes.

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