Non-woven microfiber suede composite material for automobile sunroof roller shutter and preparation method thereof

Abstract

The application provides a non-woven microfiber suede composite material for an automobile sunroof roller blind and a preparation method thereof, and belongs to the technical field of automobile interior materials. An active group layer is formed through plasma surface modification, a tension balance control system based on displacement sensors is used to dynamically adjust the differential torque of the differential roller to compensate for the difference in Young's modulus of the material, a far infrared and microwave synergistic drying system is used to optimize the interface bonding process, and a negative pressure drying chamber is used to control the emission of volatile organic compounds, so that a composite material with an interface peeling strength greater than or equal to 12 N / cm and an emission of volatile organic compounds less than or equal to 50 mu g / m3 is finally prepared, and the technical problem of insufficient interface bonding strength caused by the difference in Young's modulus of the material during the compounding of the microfiber suede base material and the shading composite film is solved.

Description

Technical Field

[0001] This invention belongs to the field of automotive interior materials technology, specifically, it relates to a non-woven microfiber suede-like composite material for automotive sunroof roller blinds and its preparation method. Background Technology

[0002] Microfiber suede-like composite materials for automotive sunroof roller blinds are typically prepared by hot-pressing a microfiber suede-like substrate with a light-blocking composite film. Traditional techniques use a constant tension control system to simultaneously feed the two materials, achieving interfacial bonding through heating and pressurization. However, in current lamination processes, the Young's modulus of the microfiber suede-like substrate is 180 to 220 MPa, while that of the light-blocking composite film is 2800 to 3200 MPa—a difference of 12 to 18 times. Traditional constant tension control cannot compensate for the deformation mismatch caused by this difference in material mechanical properties, resulting in lateral displacement deviations between the materials during pressing. In other words, existing technologies suffer from insufficient interfacial bonding strength due to the difference in Young's modulus between the microfiber suede-like substrate and the light-blocking composite film during the lamination process. Summary of the Invention

[0003] In view of this, the present invention provides a non-woven microfiber suede-like composite material for automotive sunroof roller blinds and its preparation method, which can solve the technical problem in the prior art of insufficient interfacial bonding strength caused by the difference in Young's modulus of the materials during the composite process of microfiber suede-like substrate and light-shielding composite film.

[0004] The present invention is implemented as follows: The present invention provides a first aspect of a non-woven microfiber suede-like composite material for automotive sunroof roller blinds, which is made of microfiber suede-like substrate and light-blocking composite film, wherein the microfiber suede-like substrate is composed of microfiber bundles and polyurethane resin composite.

[0005] When using a light-blocking fabric, the microfiber imitation suede substrate and the light-blocking fabric are bonded together with PUR hot melt adhesive.

[0006] The microfiber bundles have a single filament fineness of 0.1 dtex to 0.3 dtex, a polyurethane resin content of 8% to 10% by mass, a microfiber suede-like substrate thickness of 0.5 mm to 0.6 mm, and a surface density of 150 g / L. Up to 170g / .

[0007] The second aspect of this invention provides a method for preparing a nonwoven microfiber suede-like composite material for automotive sunroof roller blinds, comprising the following steps: placing a microfiber suede-like substrate in a plasma surface modification device and subjecting it to radio frequency plasma treatment in a mixed atmosphere of argon and oxygen in a certain volume ratio, thereby forming an active group layer on the surface of the microfiber suede-like substrate; pre-pressing the treated microfiber suede-like substrate and a light-shielding composite film using a three-roll laminating machine; the tension control system of the three-roll laminating machine calculating the tension deviation value based on the deformation data of the microfiber suede-like substrate and the light-shielding composite film collected by a displacement sensor, and achieving tension balance through differential roller torque adjustment; and then pre-pressing the composite intermediate... The material is fed into a far-infrared and microwave synergistic drying system, and the drying time is calculated using an interface bonding strength optimization model. The dried composite intermediate undergoes volatile organic compound (VOC) emission control treatment by placing it in a negative pressure drying chamber. The drying time is dynamically adjusted based on real-time monitoring data of VOC emissions collected by the VOC concentration monitoring unit. The treated composite intermediate is then wound using a winding device, with the winding tension calculated by a tension control system based on the material's Young's modulus difference compensation function. The finished composite material after winding undergoes quality testing, employing interface peel strength testing and VOC emission testing.

[0008] The microfiber imitation suede substrate is composed of microfiber bundles and polyurethane resin. The microfiber bundles have a single filament fineness of 0.1 dtex to 0.3 dtex, a polyurethane resin content of 8% to 10% by mass, a thickness of 0.5 mm to 0.6 mm, and a surface density of 150 g / m² to 170 g / m².

[0009] The light-shielding composite film has a three-layer composite structure, consisting of a polyethylene terephthalate light-shielding layer, a polyolefin hot melt adhesive layer, and a polypropylene nonwoven fabric layer, which are sequentially composited. The polyethylene terephthalate light-shielding layer has a thickness of 0.05 mm, the polyolefin hot melt adhesive layer has a thickness of 0.03 mm, and the polypropylene nonwoven fabric layer has a thickness of 0.08 mm.

[0010] The plasma surface modification equipment includes a vacuum chamber, a radio frequency power supply, and a gas flow control system. The vacuum level of the vacuum chamber is 80 Pa to 120 Pa, the radio frequency power supply frequency is 13.56 MHz, the argon flow rate is 150 standard cubic centimeters per minute, and the oxygen flow rate is 65 standard cubic centimeters per minute.

[0011] The active group layer includes hydroxyl, carboxyl and peroxy groups, with a thickness of 20 to 40 nanometers and an active group density of 3 to 5 active sites per square nanometer. The active group layer is used to form chemical bonds with the polyolefin hot melt adhesive layer.

[0012] The three-roll laminator includes a feed roller, a pressing roller, and a discharge roller. The feed roller has a linear speed of 8 meters per minute, the pressing roller has a pressure of 0.4 MPa to 0.6 MPa, and the discharge roller has a linear speed that is adjusted in real time according to the thickness of the composite intermediate.

[0013] The tension control system includes a displacement sensor, a tension calculation unit, and a differential roller drive unit. The displacement sensor has a sampling frequency of 100 Hz and a measurement accuracy of 0.01 mm. The tension calculation unit calculates the real-time tension value of the microfiber suede substrate and the real-time tension value of the light-shielding composite film based on the displacement sensor data.

[0014] Among them, the deformation data of the microfiber imitation suede substrate is the lateral displacement of the microfiber imitation suede substrate 10 cm in front of the pressing roller, and the deformation data of the light-shielding composite film is the lateral displacement of the light-shielding composite film 10 cm in front of the pressing roller.

[0015] The differential roller torque adjustment is achieved by adjusting the speed difference between the feed roller and the pressing roller. When the real-time tension value of the microfiber imitation suede substrate is greater than the real-time tension value of the light-shielding composite film, the feed roller speed is reduced by 0.5% to 1.5%. When the real-time tension value of the light-shielding composite film is greater than the real-time tension value of the microfiber imitation suede substrate, the feed roller speed is increased by 0.5% to 1.5%.

[0016] The far-infrared and microwave synergistic drying system includes a far-infrared heating module, a microwave generating module, and a temperature monitoring module. The far-infrared heating module uses a carbon fiber heating element with a wavelength range of 3 micrometers to 15 micrometers, and the microwave generating module has a frequency of 2450 MHz.

[0017] Among them, the interface bonding strength optimization model is a two-layer game model, which includes an upper-layer model that aims to maximize the interface bonding strength and a lower-layer model that aims to minimize energy consumption. The upper-layer model and the lower-layer model are coupled through drying time.

[0018] The negative pressure drying chamber includes a vacuum pump, a temperature control unit, and a volatile organic compound concentration monitoring unit. The vacuum pump has a pumping speed of 100 liters per minute, the temperature control unit uses a proportional-integral-derivative control algorithm, and the volatile organic compound concentration monitoring unit uses a photoionization detector.

[0019] The real-time monitoring data of volatile organic compound emissions includes the concentration values ​​of volatile organic compounds in the negative pressure drying chamber and the concentration values ​​of volatile organic compounds at the exhaust port. The drying process ends when the concentration value of volatile organic compounds in the negative pressure drying chamber is less than 20 micrograms per cubic meter and the concentration value of volatile organic compounds at the exhaust port is less than 10 micrograms per cubic meter.

[0020] Among them, the Young's modulus difference compensation function is used to calculate the winding tension compensation value. The Young's modulus of the microfiber imitation suede substrate is 180 MPa to 220 MPa, the Young's modulus of the light-shielding composite film is 2800 MPa to 3200 MPa, and the Young's modulus ratio is 12 to 18.

[0021] The winding device includes a winding roller, a tension sensor, and a speed control unit. The winding roller has a diameter of 300 mm, the tension sensor has a range of 0 N to 200 N and an accuracy of 0.5 N, and the speed control unit uses frequency conversion speed regulation.

[0022] Among them, the tension balance control adopts a multimodal tension collaborative regulation model. The multimodal tension collaborative regulation model is based on a feature fusion calculation framework with multi-head cross-attention. Through a dynamic weight allocation mechanism, it realizes deep correlation modeling between features of different dimensions in multimodal data processing.

[0023] This invention establishes a tension balance control system based on real-time monitoring by displacement sensors. It dynamically adjusts the torque of the differential roller according to the lateral displacement difference between the microfiber suede-like substrate and the light-shielding composite film, controlling the lateral displacement difference within 0.5 mm and eliminating the deformation mismatch caused by the difference in Young's modulus of the materials. By forming an active group layer on the surface of the microfiber suede-like substrate through plasma surface modification, and optimizing the interface bonding process with a far-infrared and microwave synergistic drying system, a stable chemical bond is formed between the active group layer and the polyolefin hot melt adhesive layer. In summary, this invention solves the technical problem mentioned in the background art of insufficient interfacial bonding strength caused by the difference in Young's modulus of the materials during the composite process of the microfiber suede-like substrate and the light-shielding composite film. Attached Figure Description

[0024] Figure 1 This is a flowchart of the method of the present invention.

[0025] Figure 2 The images show a comparison of the surface morphology of the microfiber suede-like substrate before and after plasma treatment.

[0026] Figure 3 This is a graph showing the change of lateral displacement difference over time during the pre-compression process.

[0027] Figure 4 This is a graph showing the change in VOC concentration over time during the negative pressure drying process.

[0028] Figure 5 This is a distribution chart showing the percentage of VOC emissions.

[0029] Figure 6 This is a comparison chart of the results of the interface peel strength test. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below.

[0031] like Figure 1 The diagram shown is a flowchart of a method for preparing a non-woven microfiber suede-like composite material for automotive sunroof roller blinds provided by the present invention. This method includes the following steps:

[0032] S01. Place the microfiber imitation suede substrate in a plasma surface modification device and perform radio frequency plasma treatment with a power of 180W for 60 seconds in a mixed atmosphere of argon and oxygen with a volume ratio of 7:3, so that an active group layer is formed on the surface of the microfiber imitation suede substrate.

[0033] S02. The microfiber imitation suede substrate and the light-shielding composite film processed in step S01 are pre-pressed together by a three-roll laminating machine. The tension control system of the three-roll laminating machine calculates the tension deviation value based on the deformation data of the microfiber imitation suede substrate and the deformation data of the light-shielding composite film collected by the displacement sensor, and achieves tension balance by adjusting the torque of the differential roller.

[0034] S03. The composite intermediate after pre-compression in step S02 is sent to a far-infrared and microwave synergistic drying system. The far-infrared heating temperature is set to 85℃, the microwave power is set to 2.5kW, and the drying time is determined by calculation using an interface bonding strength optimization model.

[0035] S04. Perform VOC emission control treatment on the composite intermediate after drying in step S03. Place the composite intermediate in a negative pressure drying chamber with a negative pressure of 15 kPa and a drying temperature of 70°C. The drying time is dynamically adjusted according to the real-time monitoring data of VOC emission collected by the VOC concentration monitoring unit.

[0036] S05. The composite intermediate processed in step S04 is wound up by a winding device. The winding tension is determined by the tension control system based on the material Young's modulus difference compensation function. The winding speed is 8m / min.

[0037] S06. The finished composite material after winding in step S05 is subjected to quality inspection. The interfacial peel strength test and VOC emission test are adopted. When the interfacial peel strength is greater than or equal to 12N / cm and the VOC emission is less than or equal to 50μg per cubic meter, it is judged as a qualified product.

[0038] The microfiber suede-like substrate is composed of microfiber bundles and polyurethane resin. The microfiber bundles have a single filament fineness of 0.1 dtex to 0.3 dtex, the polyurethane resin content is 8% to 10% by mass, the thickness of the microfiber suede-like substrate is 0.5 mm to 0.6 mm, and the surface density is 150 g / L. Up to 170g / .

[0039] The light-shielding composite film has a three-layer composite structure, consisting of a polyethylene terephthalate light-shielding layer, a polyolefin hot melt adhesive layer, and a polypropylene nonwoven fabric layer, which are sequentially laminated together. The polyethylene terephthalate light-shielding layer has a thickness of 0.05 mm, the polyolefin hot melt adhesive layer has a thickness of 0.03 mm, the polypropylene nonwoven fabric layer has a thickness of 0.08 mm, and the total thickness of the light-shielding composite film is 0.16 mm, with a light-shielding rate of ≥99.5%.

[0040] The plasma surface modification equipment includes a vacuum chamber, a radio frequency power supply, and a gas flow control system. The vacuum degree of the vacuum chamber is 80 Pa to 120 Pa, the frequency of the radio frequency power supply is 13.56 MHz, the argon flow rate is 150 sccm, and the oxygen flow rate is 65 sccm. After plasma treatment, the contact angle of the ultrafiber suede-like substrate surface is reduced from 92 degrees to 45 degrees to 55 degrees.

[0041] The active group layer includes hydroxyl, carboxyl and peroxy groups, the thickness of the active group layer is 20 nm to 40 nm, the active group density is 3 to 5 active sites per square nanometer, and the active group layer is used to form chemical bonds with the polyolefin hot melt adhesive layer.

[0042] The three-roll laminating machine includes a feed roller, a pressing roller, and a discharge roller. The linear speed of the feed roller is 8 m / min, the pressure of the pressing roller is 0.4 MPa to 0.6 MPa, the linear speed of the discharge roller is adjusted in real time according to the thickness of the composite intermediate, and the distance between the three rollers is the total thickness of the composite intermediate plus 0.1 mm.

[0043] The tension control system includes a displacement sensor, a tension calculation unit, and a differential roller drive unit. The displacement sensor has a sampling frequency of 100Hz and a measurement accuracy of 0.01mm. The tension calculation unit calculates the real-time tension value of the microfiber suede substrate and the real-time tension value of the light-shielding composite film based on the displacement sensor data.

[0044] The deformation data of the microfiber suede-like substrate is the lateral displacement of the microfiber suede-like substrate 10cm in front of the pressing roller, and the deformation data of the light-shielding composite film is the lateral displacement of the light-shielding composite film 10cm in front of the pressing roller.

[0045] The tension deviation value is calculated through the following steps: collecting deformation data of the microfiber suede-like substrate and recording it as follows. The deformation data of the light-shielding composite film were collected and recorded as follows: The difference in lateral displacement is calculated as follows: and The absolute value of the difference is used to determine the presence of tension deviation when the difference in lateral displacement is greater than 0.5 mm.

[0046] The differential roller torque adjustment is achieved by adjusting the speed difference between the feed roller and the pressing roller. When the real-time tension value of the microfiber imitation suede substrate is greater than the real-time tension value of the light-shielding composite film, the feed roller speed is reduced by 0.5% to 1.5%. When the real-time tension value of the light-shielding composite film is greater than the real-time tension value of the microfiber imitation suede substrate, the feed roller speed is increased by 0.5% to 1.5%. The torque adjustment response time is less than 0.3 seconds.

[0047] The tension balance refers to the tension state when the lateral displacement difference is less than or equal to 0.5 mm.

[0048] The far-infrared and microwave synergistic drying system includes a far-infrared heating module, a microwave generating module, and a temperature monitoring module. The far-infrared heating module uses a carbon fiber heating element with a wavelength range of 3μm to 15μm. The microwave generating module has a frequency of 2450MHz. The temperature monitoring module uses non-contact infrared temperature measurement with a temperature measurement accuracy of ±1℃.

[0049] The interface bonding strength optimization model is a two-layer game model, which includes an upper-layer model that aims to maximize the interface bonding strength and a lower-layer model that aims to minimize energy consumption. The upper-layer model and the lower-layer model are coupled through drying time.

[0050] The objective function of the upper-level model is used to calculate the optimal interfacial bonding strength, and the input includes far-infrared temperature. Microwave power and drying time The output is the target value of the upper-level model. The objective function is expressed as follows: = × × - ,in The coupling term represents the normalized value of energy consumption. The unit is ℃. The unit is kW. The unit is seconds, and the constraint is... Belongs to [75, 95], Belongs to [2.0, 3.0], It belongs to [180, 420].

[0051] The objective function of the lower-level model is used to calculate the minimum energy consumption, and the input includes far-infrared temperature. Microwave power and drying time The output is the target value of the lower-level model. The objective function is expressed as follows: = × × + ,in The coupling term represents the normalized value of the interface bonding strength. The unit is ℃. The unit is kW. The unit is seconds, and the constraint is... Belongs to [75, 95], Belongs to [2.0, 3.0], It belongs to [180, 420].

[0052] The solution steps of the interface-integrated strength optimization model specifically include: initializing the far-infrared temperature to 85℃, the microwave power to 2.5kW, and the drying time to 300 seconds; the upper-level model calculates the optimal combination of far-infrared temperature and microwave power with a fixed drying time; the lower-level model adjusts the drying time based on the output of the upper-level model to minimize energy consumption; repeating the above iterations until the upper-level model reaches its target value. If the change is less than 0.01 or the number of iterations reaches 50, the optimal combination of drying parameters will be output.

[0053] The optimal drying parameter combination includes the optimal far-infrared temperature, the optimal microwave power, and the optimal drying time. The drying time in step S03 is the optimal drying time.

[0054] The negative pressure drying chamber includes a vacuum pump, a temperature control unit, and a VOC concentration monitoring unit. The vacuum pump has a pumping speed of 100 L / min, the temperature control unit uses a PID control algorithm, and the VOC concentration monitoring unit uses a photoionization detector with a detection limit of 1 μg / L. .

[0055] The real-time monitoring data for VOC emissions includes the VOC concentration values ​​inside the negative pressure drying chamber and the VOC concentration values ​​at the exhaust port. When the VOC concentration value inside the negative pressure drying chamber is less than 20 μg / L... And the VOC concentration at the exhaust port is less than 10 μg / The drying process ends when the VOC concentration in the negative pressure drying chamber is greater than or equal to 50 μg / L. Extend the drying time by 30 minutes.

[0056] The Young's modulus difference compensation function is used to calculate the winding tension compensation value. The input includes the Young's modulus of the microfiber imitation suede substrate, the Young's modulus of the light-shielding composite film, and the winding radius. The output is the winding tension compensation value. The Young's modulus of the microfiber imitation suede substrate is 180MPa to 220MPa, the Young's modulus of the light-shielding composite film is 2800MPa to 3200MPa, and the Young's modulus ratio is 12 to 18.

[0057] The calculation steps for the Young's modulus difference compensation function of the material specifically include: measuring the Young's modulus of the microfiber imitation suede substrate, denoted as... The Young's modulus of the light-shielding composite film was measured and recorded as follows: Calculate the Young's modulus ratio as follows: Divide by Recorded as The baseline winding tension is set at 50N; the tension compensation coefficient is calculated as follows: Divide the square root of the value by 4; calculate the winding tension compensation value by multiplying the base winding tension by the tension compensation coefficient.

[0058] The winding device includes a winding roller, a tension sensor, and a speed control unit. The winding roller has a diameter of 300 mm. The tension sensor has a range of 0 N to 200 N and an accuracy of 0.5 N. The speed control unit uses frequency conversion speed regulation with a speed regulation range of 5 m / min to 15 m / min. The winding tension in step S05 uses the winding tension compensation value.

[0059] The interface peel strength test was conducted using the 90-degree peel method, with a peel speed of 100 mm / min, a peel width of 25 mm, a test temperature of 23℃, and a relative humidity of 50%. Each sample was tested 5 times and the average value was taken.

[0060] Among them, the VOC emission detection adopts 1 The environmental chamber method was used, with an internal temperature of 65℃, a relative humidity of 50%, an air exchange rate of 1 time / h, and a sampling time of 2 hours. The VOC components and contents were analyzed using gas chromatography-mass spectrometry.

[0061] The composite material product has a thickness of 0.75-0.85 mm and a unit area mass of 255-305 g / L. Light shading rate ≥ 99.5%, interfacial peel strength ≥ 12 N / cm, VOC emission ≤ 50 μg / cm. Its weather resistance meets the requirement that the strength retention rate is greater than or equal to 85% after 1000 hours of xenon lamp aging.

[0062] In step S02, the tension balance control adopts a multimodal tension collaborative regulation model. The multimodal tension collaborative regulation model is based on a feature fusion calculation framework with multi-head cross-attention. Through a dynamic weight allocation mechanism, it realizes deep correlation modeling and information integration optimization between features of different dimensions in the multimodal data processing step.

[0063] The specific structure of the multimodal tension collaborative control model is as follows: the input layer receives displacement sensor data, tension sensor data, and temperature sensor data, and each type of data is mapped into a 128-dimensional feature vector through an independent embedding layer; the multi-head cross-attention layer contains 8 attention heads, and each attention head calculates the correlation weight matrix between different modal features; the feature fusion layer obtains the fused feature vector by weighted summation of the outputs of the 8 attention heads; the fully connected layer contains 3 layers with 256, 128, and 64 nodes respectively, and the activation function adopts the modified linear unit; the output layer outputs the differential roller speed adjustment amount, and the output dimension is 1.

[0064] The steps for establishing the training dataset of the multimodal tension collaborative control model specifically include: collecting displacement sensor data, tension sensor data, temperature sensor data, and differential roller speed data during the production process of 100 batches of microfiber suede composite materials; dividing each batch of data into data segments with a length of 50 sampling points according to the time series; selecting data segments corresponding to qualified products with an interface peel strength greater than or equal to 12 N / cm as positive samples, and selecting data segments corresponding to unqualified products with an interface peel strength less than 10 N / cm as negative samples; performing data augmentation processing on the positive sample data, including adding Gaussian noise, time shifting, and amplitude scaling, with an augmentation factor of 3 times; and dividing the positive and negative samples into training and validation sets in a 7:3 ratio, with the training set containing 8400 data segments and the validation set containing 3600 data segments.

[0065] The specific steps for training the multimodal tension collaborative regulation model include: initializing model parameters using the Xavier initialization method; setting the learning rate to 0.001, batch size to 32, and training epochs to 200; using mean squared error as the loss function and the adaptive moment estimation algorithm as the optimizer; evaluating model performance on the validation set every 10 epochs; reducing the learning rate to 0.5 times the original value when the validation set loss does not decrease for 5 consecutive epochs; stopping training when the validation set loss does not decrease for 20 consecutive epochs; and saving the model parameters with the minimum validation set loss as the final model.

[0066] The tension dynamic adjustment function is used to adjust the learning rate of the multimodal tension collaborative control model. The tension dynamic adjustment function calculates the adjustment coefficient value based on the number of training rounds, the validation set loss reduction rate, and the gradient norm. Different learning rate adjustment strategies are adopted when the adjustment coefficient value belongs to different ranges.

[0067] The calculation steps of the tension dynamic adjustment function specifically include: obtaining the current training round number, denoted as... The average rate of decrease in loss over the most recent 10 validation rounds is denoted as . The gradient norm of the current batch is denoted as... ; Calculate the adjustment coefficient value Divide by 200 to the power of 0.3 and multiply by Divide the absolute value by 0.01 and then multiply by Divide by 10 to the power of 0.4; keep the learning rate unchanged when the adjustment coefficient value is in [0, 0.5); adjust the learning rate to 0.8 times the current value when the adjustment coefficient value is in [0.5, 1.2); adjust the learning rate to 0.5 times the current value when the adjustment coefficient value is in [1.2, 2.5); adjust the learning rate to 0.3 times the current value when the adjustment coefficient value is greater than or equal to 2.5.

[0068] The displacement sensor data includes deformation data of the microfiber suede-like substrate and deformation data of the light-shielding composite film; the tension sensor data includes real-time tension values ​​of the microfiber suede-like substrate and real-time tension values ​​of the light-shielding composite film; and the temperature sensor data is the surface temperature value of the pressing roller.

[0069] The differential roller speed adjustment amount is used to determine the adjustment range of the feed roller speed in step S02. When the differential roller speed adjustment amount is positive, the feed roller speed is increased; when the differential roller speed adjustment amount is negative, the feed roller speed is decreased.

[0070] The specific implementation methods of the above steps are described in detail below.

[0071] The specific implementation of step S01 involves placing the microfiber suede-like substrate into the vacuum chamber of a plasma surface modification device. Argon and oxygen are introduced into the vacuum chamber at a volume ratio of 7:3 via a gas flow control system, with the argon flow rate controlled at 150 sccm and the oxygen flow rate controlled at 65 sccm. A vacuum pump evacuates the chamber to a vacuum level between 80 Pa and 120 Pa. A radio frequency power supply outputs 180 W of radio frequency energy at a frequency of 13.56 MHz to excite the plasma. The plasma treatment lasts for 60 seconds, during which argon and oxygen ions bombard the microfiber. On the surface of the suede-like substrate, physical sputtering effect is used to remove surface contaminants and break surface molecular chains. At the same time, oxygen plasma reacts chemically with the broken molecular chains to generate hydroxyl, carboxyl, and peroxy groups, forming an active group layer with a thickness of 20nm to 40nm. The active group density reaches 3 to 5 active sites per square nanometer. The surface contact angle is reduced from 92 degrees before treatment to 45 to 55 degrees, and the surface energy is significantly improved. The active group layer provides reaction sites for subsequent chemical bonding with the polyolefin hot melt adhesive layer, solving the problem of insufficient bonding force at the heterogeneous interface between the porous surface of the microfiber suede-like substrate and the light-shielding composite film.

[0072] The specific implementation of step S02 involves feeding the plasma-treated microfiber suede-like substrate and the light-shielding composite film into a three-roll laminator via feed rollers. The feed rollers convey the two materials to the pressing rollers at a linear speed of 8 m / min. The pressing rollers apply a pressure of 0.4 MPa to 0.6 MPa to ensure close contact between the active group layer on the surface of the microfiber suede-like substrate and the polyolefin hot melt adhesive layer in the light-shielding composite film. The active groups and the hot melt adhesive molecular chains undergo a chemical bonding reaction. The discharge rollers adjust their linear speed in real time according to the thickness of the composite intermediate to complete the output of the composite intermediate. During the lamination process, a displacement sensor continuously collects the lateral displacement of the microfiber suede-like substrate and the light-shielding composite film at a sampling frequency of 100 Hz, with a collection accuracy of 0.01 mm. The tension calculation unit calculates the real-time tension of the two materials based on the lateral displacement. When the lateral displacement difference exceeds 0.5mm, a tension deviation is determined. The multimodal tension collaborative control model receives displacement sensor data, tension sensor data, and the surface temperature value of the pressing roller. It calculates the correlation weight matrix between different modal features through eight multi-head cross-attention heads. The feature fusion layer weights and sums the multimodal features and outputs the differential roller speed adjustment amount after passing through three fully connected layers. The differential roller drive unit adjusts the feed roller speed according to the positive or negative value of the speed adjustment amount. When the tension of the microfiber imitation suede substrate is too high, the feed roller speed is reduced by 0.5% to 1.5%. When the tension of the light-shielding composite film is too high, the feed roller speed is increased by 0.5% to 1.5%. The torque adjustment response time is less than 0.3 seconds, realizing dynamic tension balance based on closed-loop control, effectively eliminating the stress unevenness caused by the difference in Young's modulus between the microfiber imitation suede substrate and the light-shielding composite film.

[0073] The specific implementation of step S03 involves transporting the pre-compressed composite intermediate to a far-infrared and microwave synergistic drying system. The interface bonding strength optimization model employs a two-layer game theory algorithm to solve for the optimal drying parameters. The upper-layer model aims to maximize the interface bonding strength, taking far-infrared temperature, microwave power, and drying time as inputs. The objective function is normalized by dividing the far-infrared temperature by a baseline value of 85℃ and then taking the power of 0.6; dividing the microwave power by a baseline value of 2.5kW and then taking the power of 0.4; and dividing the drying time by 60 seconds, adding 1, and taking the natural logarithm. The product of these three terms is then subtracted from the product of the normalized energy consumption value and the coupling coefficient of 0.15. The constraints are: far-infrared temperature within the range of 75℃ to 95℃, microwave power within the range of 2.0kW to 3.0kW, and drying time within the range of 180 seconds to 420 seconds. The lower-layer model aims to minimize energy consumption, with the objective function normalized by dividing the far-infrared temperature by 85℃ and then taking the power of 1.2; and dividing the microwave power by 2.5kW. Then, take the 1.5th power, divide the drying time by 300 seconds, multiply the three terms, and add the product of the normalized value of the interface bonding strength and the coupling coefficient of 0.15. The constraints are the same as the upper-level model. The model solution process first initializes the far-infrared temperature to 85℃, the microwave power to 2.5kW, and the drying time to 300 seconds. The upper-level model calculates the optimal far-infrared temperature and microwave power with a fixed drying time. The lower-level model adjusts the drying time according to the upper-level output to minimize energy consumption. Iterative calculation is performed until the change in the target value of the upper-level model is less than 0.01 or the number of iterations reaches 50. The optimal combination of drying parameters is output. The far-infrared heating module uses a carbon fiber heating element with a wavelength of 3μm to 15μm to heat from the outside to the inside. The microwave generating module generates electromagnetic waves at a frequency of 2450MHz to polarize the water molecules inside the composite intermediate and generate heat from the inside to the outside. The far-infrared and microwave work together to achieve synchronous drying inside and outside, shortening the drying time while ensuring that the interface bonding strength reaches the optimal value.

[0074] The specific implementation of step S04 involves transferring the dried composite intermediate to a negative pressure drying chamber. A vacuum pump evacuates the drying chamber to a negative pressure of 15 kPa at a pumping rate of 100 L / min. The temperature control unit uses a PID control algorithm to stabilize the drying temperature at 70°C. The negative pressure environment lowers the boiling point of the organic solvent, accelerating the volatilization of residual solvents in the polyolefin hot melt adhesive layer and polyurethane resin. The VOC concentration monitoring unit uses a photoionization detector to continuously monitor the VOC concentration values ​​inside the drying chamber and at the exhaust port, with a detection limit of 1 μg / L. When the VOC concentration in the drying chamber is less than 20 μg / And the VOC concentration at the exhaust port is less than 10 μg / When VOC emission is deemed essentially complete and the drying process ends, the VOC concentration in the drying chamber is greater than or equal to 50 μg / L. When it is determined that the VOC emission is insufficient, the drying time is extended by 30 minutes. Through real-time monitoring and dynamic adjustment, the VOC emission is ensured to be controlled within 50 μg / As follows, negative pressure drying combined with temperature control solves the contradiction between traditional long-time baking and production efficiency.

[0075] The specific implementation of step S05 is to transport the composite intermediate after VOC treatment to the winding device. The material Young's modulus difference compensation function calculates the Young's modulus ratio based on the Young's modulus of the superfine suede substrate ranging from 180 MPa to 220 MPa and the Young's modulus of the light-shielding composite film ranging from 2800 MPa to 3200 MPa. The ratio range is 12 to 18. The calculated tension compensation coefficient is the square root of the Young's modulus ratio divided by 4. The reference winding tension is set at 50 N, and the winding tension compensation value is the reference winding tension multiplied by the tension compensation coefficient. The tension sensor monitors the winding tension in real time and feeds it back to the speed control unit. The speed control unit uses variable frequency speed regulation technology to stabilize the winding speed at 8 m / min. The diameter of the winding roller is 300 mm. By dynamically adjusting the winding tension, the stress deviation caused by the difference in material Young's modulus is compensated, preventing wrinkles or flanging phenomena during the winding process, and ensuring that the flatness of the composite material finished product meets the usage requirements.

[0076] The specific implementation of step S06 is to conduct interface peel strength testing and VOC emission detection on the wound composite material finished product. The 90-degree peel method is used for the interface peel strength testing. The peel speed is set at 100 mm / min, and the peel width is 25 mm. The test environment temperature is 23°C and the relative humidity is 50%. Each sample is tested 5 times and the average value is taken. When the average interface peel strength is greater than or equal to 12 N / cm, it is determined that the interface bonding quality is qualified. The VOC emission detection uses 1 the environmental chamber method. The sample is placed in an environment with a chamber temperature of 65°C, a relative humidity of 50%, and an air replacement rate of 1 time / h for 2 hours. A gas chromatography-mass spectrometry联用仪 is used to analyze the VOC components and contents in the air in the chamber. When the VOC emission is less than or equal to 50 μg / When it is determined that the VOC control meets the standard, the product that meets both the interface peel strength and VOC emission indicators is determined to be a qualified product.

[0077] The key technical concepts of this invention include plasma surface modification technology to construct an active group layer, a multimodal tension synergistic control model to achieve dynamic tension balance, a two-layer game model to optimize drying parameters, and a negative pressure drying system to control VOC emissions. The plasma surface modification technology introduces high-density active groups onto the surface of the microfiber suede-like substrate by bombarding the surface with argon-oxygen mixed plasma. These active groups chemically bond with the hot melt adhesive layer in the light-shielding composite film. Compared to traditional physical bonding methods, chemical bonding provides stronger interfacial adhesion, solving the interfacial delamination problem caused by the porous and low surface energy characteristics of microfiber suede-like materials, and increasing the interfacial peel strength to over 12 N / cm. The multimodal tension synergistic control model integrates multi-dimensional sensor data such as displacement, tension, and temperature based on a multi-head cross-attention mechanism. Through dynamic weight allocation, it captures the deep correlation between different modal data. Compared to traditional single-sensor feedback control, multimodal fusion can more accurately identify the source of tension deviation and achieve millisecond-level response adjustment, effectively eliminating stress unevenness caused by a 12- to 18-fold difference in Young's modulus, and controlling the lateral displacement difference within 0.5 mm. The two-layer game theory model, through coupled optimization of maximizing the upper-layer interface bonding strength and minimizing the lower-layer energy consumption, shortens the drying time while ensuring interface quality. Compared with traditional empirical parameter settings, game theory optimization achieves a dual improvement in quality and efficiency. The negative pressure drying system utilizes the principle of lowering the solvent boiling point through negative pressure to achieve rapid VOC emission at a low temperature of 70℃. Compared with traditional high-temperature, long-term baking, this shortens the production cycle and reduces the risk of thermal damage. The synergistic effect of the above technical approaches forms a complete low-VOC composite material preparation process chain. Plasma modification lays the foundation for interface bonding, tension synergistic control ensures the stability of the composite process, game theory-optimized drying balances quality and efficiency, and negative pressure drying achieves environmental compliance. These four technologies work together to solve the core challenges of interface bonding, tension control, drying efficiency, and VOC emission in the preparation of microfiber suede-like composite materials, achieving the goal of preparing high-strength, low-VOC, and high-efficiency composite materials.

[0078] It should be noted that this invention also solves the following technical problem: in the preparation of microfiber suede-like composite materials, traditional constant-temperature and constant-power drying processes struggle to achieve a balance between interfacial bonding strength and energy consumption. This invention addresses this by establishing a two-layer game-theoretic optimization model. The upper-layer model calculates the optimal far-infrared temperature and microwave power combination with the goal of maximizing interfacial bonding strength, while the lower-layer model adjusts the drying time with the goal of minimizing energy consumption. The two models achieve synergistic optimization through drying time coupling, and the optimal combination of drying parameters is output through iterative calculation, thereby reducing energy consumption while ensuring the quality of interfacial bonding. Furthermore, this invention also solves the technical problem of effectively controlling the emission of volatile organic compounds (VOCs) in finished composite materials. By using a negative pressure drying chamber in conjunction with a VOC concentration monitoring unit to monitor the VOC concentration values ​​inside the negative pressure drying chamber and at the exhaust port in real time, the drying time is dynamically adjusted based on the monitoring data. The drying process ends when the VOC concentration value inside the negative pressure drying chamber is less than 20 micrograms per cubic meter and the VOC concentration value at the exhaust port is less than 10 micrograms per cubic meter, ensuring that the VOC emission of the final product meets the requirements of the vehicle interior air quality standards.

[0079] Specifically, the principle of this invention is as follows: The technical solution of this invention can solve the above-mentioned technical problems by using a displacement sensor to monitor the lateral displacement of the microfiber suede-like substrate and the light-shielding composite film at a sampling frequency of 100 Hz in real time at a distance of 10 cm in front of the pressing roller. The tension calculation unit judges the tension imbalance between the materials based on the lateral displacement difference. When the lateral displacement difference is greater than 0.5 mm, the differential roller drive unit adjusts the feed roller speed by 0.5% to 1.5% within 0.3 seconds. The speed difference compensates for the deformation difference caused by the difference in Young's modulus of the materials, so that the two materials maintain lateral position synchronization during pressing. Plasma surface modification introduces hydroxyl carboxyl groups and peroxy groups on the surface of the microfiber suede-like substrate. The density of active groups reaches 3 to 5 active sites per square nanometer, providing sufficient reaction sites for interfacial chemical bonding. Combined with the 85°C far-infrared temperature and 2.5 kW microwave power provided by the far-infrared and microwave synergistic drying system, the cross-linking reaction between the active groups and the molecular chain segments of the polyolefin hot melt adhesive layer is promoted, forming a stable covalent bond network structure, thereby improving the interfacial bonding strength.

[0080] The following provides a specific embodiment 1 of the present invention, and the specific implementation of each step in this embodiment 1 is described in detail below.

[0081] The specific implementation of step S01 is as follows: The microfiber suede-like substrate is placed in the vacuum chamber of the plasma surface modification equipment. The vacuum pump is started to evacuate the vacuum chamber to a vacuum level of 80 Pa to 120 Pa. Argon and oxygen are introduced into the vacuum chamber through the gas flow control system. The argon flow rate is set to 150 standard cubic centimeters per minute, and the oxygen flow rate is set to 65 standard cubic centimeters per minute, so that the volume ratio of argon to oxygen is 7:3. After the gas flow rate stabilizes, the radio frequency power supply is started. The radio frequency power supply frequency is 13.56 MHz, and the power is set to 180 watts. The microfiber suede-like substrate is subjected to radio frequency plasma treatment for 60 seconds in a mixed atmosphere. The high-energy particles in the plasma bombard the surface of the microfiber suede-like substrate, breaking the surface molecular chains and introducing hydroxyl, carboxyl, and peroxy groups to form an active group layer with a thickness of 20 nanometers to 40 nanometers. The active group density reaches 3 to 5 active sites per square nanometer. After treatment, the surface contact angle of the microfiber suede-like substrate is reduced from 92 degrees to 45 degrees to 55 degrees.

[0082] The specific implementation of step S02 is as follows: The microfiber suede-like substrate and the light-shielding composite film processed in step S01 are fed into the three-roll laminator from the feed rollers. The linear speed of the feed rollers is set to 8 meters per minute. The two materials meet and are pre-pressed at the pressing roller. The pressure of the pressing roller is set to 0.4 MPa to 0.6 MPa. A displacement sensor monitors the lateral displacement of the microfiber suede-like substrate and the light-shielding composite film 10 cm in front of the pressing roller in real time at a sampling frequency of 100 Hz. The tension calculation unit collects the displacement sensor data and calculates the tension deviation value. Real-time tension value of the microfiber suede-like substrate. The calculation formula is expressed as follows:

[0083] ;

[0084] In the formula This represents the real-time tension value of the microfiber suede-like substrate, in Newtons (N). The Young's modulus of the microfiber suede-like substrate is expressed in megapascals (MPA). The cross-sectional area of ​​the microfiber suede-like substrate is expressed in square millimeters. The value represents the lateral displacement of the microfiber suede-like substrate, in millimeters. For reference length, the unit is millimeters, the default is 100 millimeters. Real-time tension value of the light-blocking composite film. The calculation formula is expressed as follows:

[0085] ;

[0086] In the formula This is the real-time tension value of the light-shielding composite film, in Newtons. The value represents the Young's modulus of the light-shielding composite film, expressed in megapascals (MPA). The cross-sectional area of ​​the light-shielding composite film is expressed in square millimeters. The value represents the lateral displacement of the light-shielding composite film, expressed in millimeters. The specific calculation steps are as follows: The lateral displacement of the microfiber suede-like substrate is measured 10 cm in front of the pressing roller and recorded as follows: The unit is millimeters. The lateral displacement of the light-shielding composite film at a position 10 cm in front of the pressing roller is recorded as _____. Calculate the lateral displacement difference, in millimeters. The formula is expressed as follows:

[0087] ;

[0088] In the formula This represents the lateral displacement difference, in millimeters. When a tension deviation is detected at a millimeter, the differential roller drive unit adjusts the feed roller speed based on the deviation value. When the real-time tension value of the microfiber suede-like substrate is greater than that of the light-shielding composite film, the feed roller speed is reduced by 0.5% to 1.5%. When the real-time tension value of the light-shielding composite film is greater than that of the microfiber suede-like substrate, the feed roller speed is increased by 0.5% to 1.5%. (Feed roller speed adjustment amount) The calculation formula is expressed as follows:

[0089] ;

[0090] In the formula This refers to the adjustment amount of the feed roller speed, expressed in meters per minute. The initial linear velocity of the feed roller is in meters per minute, with a default value of 8 meters per minute. The torque adjustment response time is less than 0.3 seconds until the lateral displacement difference is less than or equal to 0.5 millimeters to achieve tension balance.

[0091] The specific implementation of step S03 is as follows: The composite intermediate after pre-compression in step S02 is fed into a far-infrared and microwave synergistic drying system. The far-infrared heating module uses a carbon fiber heating element with a wavelength range of 3 micrometers to 15 micrometers and the far-infrared heating temperature is set to 85°C. The microwave generating module has a frequency of 2450 MHz and a microwave power of 2.5 kW. The drying time is determined by calculating the interface bonding strength optimization model. The interface bonding strength optimization model is a two-layer game model, including an upper-layer model and a lower-layer model. The objective function of the upper-layer model is used to calculate the optimal interface bonding strength, and the formula is expressed as follows:

[0092] ;

[0093] In the formula The objective value of the upper-level model is dimensionless. Far-infrared temperature, in °C. This refers to microwave power, measured in kilowatts. Drying time, in seconds. Let the coupling term represent the normalized energy consumption value, which is dimensionless, and the constraint condition is: The temperature ranges from 75 to 95 degrees Celsius. It belongs to the 2.0 to 3.0 kilowatt range. It falls within the range of 180 to 420 seconds. The calculation formula is expressed as follows:

[0094] ;

[0095] In the formula The far-infrared temperature in the lower-level model, in °C. This represents the microwave power in the lower-level model, in kilowatts. The drying time in the lower-level model is expressed in seconds. The objective function of the lower-level model is used to calculate the minimum energy consumption, and the formula is as follows:

[0096] ;

[0097] In the formula The target value of the lower-level model is dimensionless. The coupling term represents the normalized value of the interface bonding strength, which is dimensionless, and the constraint condition is: The temperature ranges from 75 to 95 degrees Celsius. It belongs to the 2.0 to 3.0 kilowatt range. It falls within the range of 180 to 420 seconds. The calculation formula is expressed as follows:

[0098] ;

[0099] In the formula The value represents the theoretical maximum value of the upper-level model's objective, which is dimensionless and has an empirical value of 1.5. The solution steps are as follows: initialize the far-infrared temperature to 85℃, the microwave power to 2.5 kW, and the drying time to 300 seconds. The upper-level model calculates the optimal combination of far-infrared temperature and microwave power with a fixed drying time. The lower-level model adjusts the drying time based on the upper-level model's output to minimize energy consumption. This process is repeated iteratively until the upper-level model's objective value is reached. If the change is less than 0.01 or the number of iterations reaches 50, the optimal combination of drying parameters is output, including the optimal far-infrared temperature, the optimal microwave power, and the optimal drying time. The optimal drying time is used in step S03.

[0100] The specific implementation of step S04 is as follows: the composite intermediate dried in step S03 is placed in a negative pressure drying chamber, the vacuum pump is started to evacuate the negative pressure drying chamber to a negative pressure of 15 kPa, the pumping rate is 100 L / min, the temperature control unit uses a proportional-integral-derivative control algorithm to control the drying temperature at 70℃, the volatile organic compound concentration monitoring unit uses a photoionization detector to monitor the volatile organic compound concentration values ​​in the negative pressure drying chamber and the volatile organic compound concentration values ​​at the exhaust port in real time, the detection limit is 1 μg / m³, the drying process ends when the volatile organic compound concentration value in the negative pressure drying chamber is less than 20 μg / m³ and the volatile organic compound concentration value at the exhaust port is less than 10 μg / m³, the drying time is extended by 30 minutes when the volatile organic compound concentration value in the negative pressure drying chamber is greater than or equal to 50 μg / m³.

[0101] The specific implementation of step S05 is as follows: the composite intermediate processed in step S04 is wound using a winding device. The winding tension is determined by the tension control system based on the material Young's modulus difference compensation function. The calculation steps for the material Young's modulus difference compensation function are as follows: the Young's modulus of the microfiber suede-like substrate is measured and denoted as... The range is from 180 MPa to 220 MPa. The Young's modulus of the light-shielding composite film is measured and recorded as follows: The range is from 2800 MPa to 3200 MPa. Calculate the Young's modulus ratio. The formula is expressed as follows:

[0102] ;

[0103] In the formula Given the Young's modulus ratio, which is dimensionless and ranges from 12 to 18, and setting the baseline winding tension to 50 Newtons, calculate the tension compensation coefficient. The formula is expressed as follows:

[0104] ;

[0105] In the formula The tension compensation coefficient is dimensionless. Calculate the winding tension compensation value. The formula is expressed as follows:

[0106] ;

[0107] In the formula The winding tension compensation value is in Newtons (N). The winding speed is set to 8 meters per minute. The tension sensor range is 0 to 200 N with an accuracy of 0.5 N. The speed control unit uses frequency conversion speed regulation with a speed range of 5 to 15 meters per minute.

[0108] The specific implementation of the tension dynamic adjustment function is as follows: obtain the current training round number, denoted as... The average rate of decrease in loss over the most recent 10 validation rounds is denoted as . The gradient norm of the current batch is denoted as... Calculate the adjustment coefficient value The formula is expressed as follows:

[0109] ;

[0110] In the formula The adjustment coefficient value is dimensionless. This is the current training epoch, dimensionless. The average rate of decrease in loss over the most recent 10 validation rounds, dimensionless. Let be the gradient norm of the current batch, which is dimensionless. When the learning rate is between 0 and 0.5, the learning rate remains constant. When the value is between 0.5 and 1.2, adjust the learning rate to 0.8 times the current value. When the learning rate is between 1.2 and 2.5, adjust it to 0.5 times the current value. When the learning rate is greater than or equal to 2.5, adjust it to 0.3 times the current value.

[0111] It should be noted that the variables involved in this embodiment are explained in detail in Table 1.

[0112] Table 1. Variable Explanation Table

[0113] To better understand and implement this invention, the following is a specific application scenario example 2: To address the technical challenges of insufficient interfacial bonding strength, excessive VOC emissions, and wrinkles easily generated during the composite process in practical applications of automotive sunroof roller blind materials, technicians conducted a complete production test using the preparation method of this invention. The test used a microfiber imitation suede substrate and a light-blocking composite film provided by an automotive parts manufacturer as raw materials. The microfiber imitation suede substrate had a single filament fineness of 0.2 dtex, a polyurethane resin content of 10% by mass, a substrate thickness of 0.55 mm, and a surface density of 155 g / L. The initial surface contact angle is 92 degrees. The light-shielding composite film is composed of a 0.05mm thick polyethylene terephthalate light-shielding layer, a 0.03mm thick polyolefin hot melt adhesive layer, and a 0.08mm thick polypropylene nonwoven fabric layer, with a total thickness of 0.16mm and a light-shielding rate of 99.6%.

[0114] Technicians first placed the microfiber suede-like substrate in a plasma surface modification device, setting the argon flow rate to 150 sccm, the oxygen flow rate to 65 sccm, and the vacuum level in the vacuum chamber to a stable 95 Pa. The radio frequency power supply output 180W of power at a frequency of 13.56MHz for plasma treatment, with a treatment time of 60 seconds. After treatment, the contact angle of the microfiber suede-like substrate surface decreased to 48 degrees, the surface energy significantly increased, the active group layer thickness measured by atomic force microscopy was 30 nm, and the active group density reached 4 active sites per square nanometer. Figure 2 As shown, the surface morphology of the microfiber suede-like substrate changed significantly before and after plasma treatment. The surface roughness increased after treatment, providing sufficient reaction sites for subsequent chemical bonding.

[0115] Plasma-modified microfiber suede-like substrate and light-shielding composite film were pre-pressed together using a three-roll laminator. The feed roller linear speed was set to 8 m / min, the pressing roller pressure to 0.5 MPa, and the three-roller spacing to 0.75 mm. Displacement sensors collected lateral displacement data of both materials at a frequency of 100 Hz. During the test, the lateral displacement of the microfiber suede-like substrate 10 cm in front of the pressing roller fluctuated between 0.15 mm and 0.35 mm, while the lateral displacement of the light-shielding composite film fluctuated between 0.10 mm and 0.30 mm. Tension sensors simultaneously collected real-time tension values ​​of both materials. The tension of the microfiber suede-like substrate ranged from 45 N to 55 N, and the tension of the light-shielding composite film ranged from 42 N to 52 N. A multimodal tension collaborative control model received data from the displacement sensor, tension sensor, and the surface temperature of the pressing roller, which remained stable between 68°C and 72°C. The model calculates the correlation weights of different modal features using eight multi-head cross-attention heads. When the detected lateral displacement difference reaches 0.6 mm, the model outputs a differential roller speed adjustment of -0.8%. The differential roller drive unit reduces the feed roller speed by 0.8% within 0.25 seconds, and the lateral displacement difference quickly falls back to within 0.3 mm, achieving dynamic tension balance. Figure 3 As shown, the lateral displacement difference was always controlled within 0.5mm throughout the entire pre-compression process, and the surface flatness of the composite intermediate was good.

[0116] The pre-compressed composite intermediate was then placed in a far-infrared and microwave synergistic drying system. An interface bonding strength optimization model calculated the optimal drying parameters using a two-layer game theory algorithm. The model was initialized with a far-infrared temperature of 85℃, a microwave power of 2.5kW, and a drying time of 300 seconds. After 38 iterations, the change in the upper-level model's target value decreased to 0.008, and the model output the optimal drying parameter combination as a far-infrared temperature of 88℃, a microwave power of 2.7kW, and a drying time of 342 seconds. During the drying process, a temperature monitoring module collected the surface temperature of the composite intermediate in real time. The temperature curve showed that the temperature rapidly rose to 85℃ within the first 120 seconds, then stabilized in the range of 86℃ to 90℃, and drying was completed after 342 seconds. The dried composite intermediate underwent preliminary interface peel strength testing, with an average peel strength of 13.2 N / cm, meeting the interface bonding quality requirements.

[0117] The composite intermediate was then transferred to a negative pressure drying chamber for VOC emission control. A vacuum pump evacuated the chamber to a negative pressure of 15 kPa, and a temperature control unit stabilized the drying temperature at 70°C. A VOC concentration monitoring unit continuously monitored the VOC concentration inside the drying chamber and the VOC concentration at the exhaust port. Initially, the VOC concentration inside the drying chamber was 156 μg / L. The VOC concentration at the exhaust port was 89 μg / L. After 45 minutes of drying, the VOC concentration in the drying chamber dropped to 18 μg / L. The VOC concentration at the exhaust port decreased to 8 μg / L. The conditions for ending the drying process were met. During the drying process, the VOC emission rate exhibited a characteristic of being rapid initially and then slowing down; the VOC concentration decreased at a rate of 6.9 μg / L in the first 20 minutes. The rate of decline decreased to 2.4 μg / min over the last 25 minutes. Every minute. Figure 4 As shown, the VOC concentration decreased exponentially with drying time, and the negative pressure environment effectively accelerated the volatilization of residual solvents.

[0118] The VOC-treated composite intermediate was wound using a winding device. The Young's modulus difference compensation function was used to calculate a Young's modulus ratio of 15 based on the Young's modulus of the microfiber suede-like substrate (200 MPa) and the light-shielding composite film (3000 MPa). The calculated tension compensation coefficient was 0.969, and the winding tension compensation value was 48.4 N. During the winding process, a tension sensor monitored the winding tension in real time, and the actual winding tension remained stable within the range of 47.8 N to 49.2 N. The winding speed was maintained at 8 m / min, and the winding roller diameter was 300 mm. The thickness of the finished composite material after winding was measured to be 0.79 mm, and the unit area mass was 278 g / m². The shading rate is 99.9%.

[0119] Technicians conducted comprehensive quality inspections on the prepared composite material products. The interfacial peel strength test was performed using the 90-degree peel method, with a peel speed of 100 mm / min, a peel width of 25 mm, and an ambient temperature of 23℃ and a relative humidity of 50%. Each sample was tested five times, and the test results are shown in Table 2.

[0120] Table 2 Results of interfacial peel strength test

[0121] As can be seen from the data in Table 1, the average interfacial peel strength of the five samples is greater than 12 N / cm, which meets the quality requirements. Among them, the average peel strength of sample 3 reaches 13.6 N / cm, showing excellent interfacial bonding performance.

[0122] VOC emission detection uses 1 The environmental chamber method involved placing the sample in an environment with a temperature of 65℃, relative humidity of 50%, and an air exchange rate of 1 time / h for 2 hours. Gas chromatography-mass spectrometry (GC-MS) was used to analyze the VOC components and content in the chamber air. The results showed that the main VOC components were toluene, xylene, and butyl acetate, with a total VOC emission of 42 μg / L. Far below 50 μg / Limit requirements. For example... Figure 5 As shown, the emission percentages of different VOC components are as follows: toluene accounts for 35%, xylene accounts for 28%, butyl acetate accounts for 22%, and other components account for 15%.

[0123] Technicians also conducted weather resistance tests on the finished composite materials, using a xenon lamp aging test chamber to simulate the natural environment with an irradiation intensity of 550W / The blackboard temperature was 65℃, the relative humidity was 50%, and the interfacial peel strength was tested after 1000 hours of continuous aging. The average interfacial peel strength of the aged sample was 11.5 N / cm, with a strength retention rate of 86.5%, meeting the weathering performance requirement of a strength retention rate of greater than or equal to 85%. During the aging process, no obvious fading, cracking, or blistering was observed on the surface of the composite material, and the light-blocking rate remained above 99.5%.

[0124] This invention utilizes plasma surface modification technology to construct a high-density active group layer on the surface of a microfiber suede-like substrate. The active groups undergo a chemical bonding reaction with the hot-melt adhesive layer in the light-shielding composite film, forming a stable chemical bonding interface. Compared to traditional physical bonding methods that rely on weak van der Waals forces, chemical bonding provides stronger interfacial adhesion, fundamentally solving the problem of insufficient bonding strength at heterogeneous interfaces. The multimodal tension collaborative control model, based on a multi-head cross-attention mechanism, fuses multi-dimensional sensor data such as displacement, tension, and temperature. Through dynamic weight allocation, it captures the deep correlation between different modal data, achieving millisecond-level dynamic tension balance control. Compared to traditional single-sensor feedback control, which can only respond to tension changes in a single dimension, multimodal fusion can more comprehensively and accurately identify the source of tension deviation and implement precise adjustments, effectively eliminating stress unevenness caused by differences in Young's modulus of the materials. The two-layer game theory model optimizes drying parameters by maximizing the strength of the upper interface and minimizing energy consumption in the lower layer, while ensuring interface quality. Compared to traditional experience-based parameter settings that rely on operator experience and are fixed and cannot adapt to batch-to-batch material variations, game theory optimization achieves both adaptive parameter adjustment and improved quality and efficiency. The negative pressure drying system utilizes the principle of lowering the solvent boiling point through negative pressure, achieving rapid VOC emission at a low temperature of 70℃. Compared to traditional high-temperature, long-duration baking that requires several hours at temperatures above 90℃, negative pressure drying shortens the production cycle, reduces the risk of thermal damage to material properties, and ensures that VOC emissions are controlled within healthy and environmentally friendly standards.

[0125] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A non-woven microfiber suede-like composite material for low-density automotive sunroof roller blinds, characterized in that, It is made by combining a microfiber imitation suede substrate with a light-blocking cloth or a light-blocking composite film. The microfiber imitation suede substrate is composed of ultra-fine fiber bundles and polyurethane resin.

2. The non-woven microfiber suede-like composite material for low-density automotive sunroof roller blinds according to claim 1, characterized in that, The microfiber bundles have a single filament fineness of 0.1 to 0.3 dtex, a polyurethane resin content of 8% to 10% by mass, a microfiber suede-like substrate thickness of 0.5 to 0.6 mm, and a surface density of 150 to 170 g / L. .

3. The non-woven microfiber suede-like composite material for low-density automotive sunroof roller blinds according to claim 1, characterized in that, When using a light-blocking fabric, the microfiber imitation suede substrate and the light-blocking fabric are bonded together with PUR hot melt adhesive.

4. A method for preparing a nonwoven microfiber suede-like composite material for low-density automotive sunroof roller blinds, characterized in that, Includes the following steps: The microfiber suede-like substrate is placed in a plasma surface modification device and subjected to radio frequency plasma treatment in a mixed atmosphere of argon and oxygen, forming an active group layer on the surface of the substrate. The treated microfiber suede-like substrate and a light-shielding composite film are then pre-pressed together using a two-roll laminator. The tension control system of the two-roll laminator calculates the tension deviation based on the deformation data of the microfiber suede-like substrate and the light-shielding fabric collected by displacement sensors, and achieves tension balance through differential roller torque adjustment. The pre-pressed composite intermediate is then sent to a far-infrared and microwave synergistic drying system, with the drying time determined by a specified threshold. The surface bonding strength was determined by calculation using an optimization model. The dried composite intermediate underwent volatile organic compound (VOC) emission control treatment. The intermediate was placed in a negative pressure drying chamber, and the drying time was dynamically adjusted based on real-time monitoring data of VOC emissions collected by the VOC concentration monitoring unit. The treated composite intermediate was then wound using a winding device, with the winding tension calculated by a tension control system based on the material's Young's modulus difference compensation function. The finished composite material after winding underwent quality testing, employing interfacial peel strength testing and VOC emission testing.

5. The preparation method of the nonwoven microfiber suede-like composite material for low-density automotive sunroof roller blinds according to claim 4, characterized in that, The light-shielding composite film has a three-layer composite structure, consisting of a polyethylene terephthalate light-shielding layer, a polyolefin hot melt adhesive layer, and a polypropylene nonwoven fabric layer, which are sequentially laminated together. The polyethylene terephthalate light-shielding layer has a thickness of 0.05 mm, the polyolefin hot melt adhesive layer has a thickness of 0.03 mm, and the polypropylene nonwoven fabric layer has a thickness of 0.08 mm.

6. The preparation method of the nonwoven microfiber suede-like composite material for low-density automotive sunroof roller blinds according to claim 5, characterized in that, The plasma surface modification equipment includes a vacuum chamber, a radio frequency power supply, and a gas flow control system. The vacuum level of the vacuum chamber is 80 Pa to 120 Pa, the radio frequency power supply frequency is 13.56 MHz, the argon flow rate is 150 standard cubic centimeters per minute, and the oxygen flow rate is 65 standard cubic centimeters per minute.

7. The preparation method of the nonwoven microfiber suede-like composite material for low-density automotive sunroof roller blinds according to claim 6, characterized in that, The active group layer includes hydroxyl, carboxyl and peroxy groups. The thickness of the active group layer is 20 nanometers to 40 nanometers, and the active group density is 3 to 5 active sites per square nanometer. The active group layer is used to form chemical bonds with the polyolefin hot melt adhesive layer.

8. The preparation method of the nonwoven microfiber suede-like composite material for low-density automotive sunroof roller blinds according to claim 7, characterized in that, The three-roll laminator includes a feed roller, a pressing roller, and a discharge roller. The linear speed of the feed roller is 8 meters per minute, the pressure of the pressing roller is 0.4 MPa to 0.6 MPa, and the linear speed of the discharge roller is adjusted in real time according to the thickness of the composite intermediate.

9. The preparation method of the nonwoven microfiber suede-like composite material for low-density automotive sunroof roller blinds according to claim 8, characterized in that, The tension control system includes a displacement sensor, a tension calculation unit, and a differential roller drive unit. The displacement sensor has a sampling frequency of 100 Hz and a measurement accuracy of 0.01 mm. The tension calculation unit calculates the real-time tension value of the microfiber suede substrate and the real-time tension value of the light-shielding composite film based on the displacement sensor data.

10. The preparation method of the nonwoven microfiber suede-like composite material for low-density automotive sunroof roller blinds according to claim 9, characterized in that, The deformation data of the microfiber imitation suede substrate is the lateral displacement of the microfiber imitation suede substrate 10 cm in front of the pressing roller, and the deformation data of the light-shielding composite film is the lateral displacement of the light-shielding composite film 10 cm in front of the pressing roller.

Images