A microstructure molding process based on elastomeric film materials

Abstract

The application discloses a microstructure forming preparation process based on an elastomer film material, and is characterized by comprising the following steps: unwinding a base film and a mother film; preheating and softening the base film and the mother film; hot-pressing forming through a hot-pressing roller structure, wherein the hot-pressing roller structure is sequentially provided with a plurality of temperature zones and a plurality of pressure zones along the running direction of the base film and the mother film, the temperature of each temperature zone gradually decreases along the running direction, the pressure of each pressure zone gradually increases and then decreases along the running direction, and the gradient forming of the microstructure is realized through the collaborative control of the segmented temperature and the segmented pressure; cooling forming; peeling off the mother film and winding up. The overall device structure is compact and small in floor space, the natural flattening effect of the roller system is utilized, the overall flatness of the film after pressing is significantly improved, a heating-pressing integrated uniform temperature field cavity is designed, and the base film and the mother film are pressed in the cavity.

Description

Technical Field

[0001] This invention relates to the field of polymer functional thin film materials and micro / nano fabrication technology, specifically to a microstructure forming and preparation process based on elastomeric film materials. Background Technology

[0002] TPU drag-reducing films suffer from several drawbacks, including short-lived drag-reduction effects, easily worn microstructures, complex manufacturing processes, and difficulty in achieving a balance between mechanical properties and drag-reduction performance. In particular, traditional imprinting processes suffer from poor temperature, pressure, and tension matching, leading to incomplete microstructure filling, film stretching deformation, or peeling damage, making continuous, high-precision, large-scale production difficult. In existing hot pressing processes, temperature and pressure are typically set as independent variables, with the temperature and pressure parameters of each pressure roller or zone often employing a single constant value or simple linear variation, lacking a coordinated gradient control strategy along the film's running direction. This results in the inability to precisely match the rheological state and stress conditions required by the base film at each stage of hot pressing in continuous production, leading to prominent problems such as incomplete microstructure filling, film stretching deformation, or peeling damage. Furthermore, different hot pressing equipment configurations (such as tandem roller and center roller types) exhibit different response characteristics to process parameters, making it difficult to achieve stable transfer of existing processes between different equipment configurations, thus restricting the process versatility for large-scale production. Summary of the Invention

[0003] The purpose of this invention is to provide a microstructure forming and preparation process based on elastomeric membrane materials to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a microstructure fabrication process based on an elastomer membrane material, the fabrication process comprising: S1. Unwinding of the base film and mother film; S2. Preheat and soften the base film and mother film; S3. Hot pressing is performed by a hot press roller structure. The hot press roller structure is provided with multiple temperature zones and multiple pressure zones in sequence along the running direction of the base film and the mother film. The temperature of each temperature zone decreases step by step along the running direction, and the pressure of each pressure zone increases first and then decreases along the running direction. Gradient forming of microstructure is achieved by the coordinated control of segmented temperature and segmented pressure. S4, Cooling and molding; S5. Peel off the mother film and roll it up.

[0005] Preferably, the plurality of temperature zones include a first temperature zone, a second temperature zone, a third temperature zone, a fourth temperature zone, a fifth temperature zone, and a sixth temperature zone arranged sequentially along the running direction of the base film and the mother film, wherein the temperature of the first temperature zone to the sixth temperature zone decreases sequentially.

[0006] Preferably, the temperature of the first temperature zone is set to 145-150℃, the temperature of the second temperature zone is set to 140-145℃, the temperature of the third temperature zone is set to 135-140℃, the temperature of the fourth temperature zone is set to 130-135℃, the temperature of the fifth temperature zone is set to 125-130℃, and the temperature of the sixth temperature zone is set to 120-125℃.

[0007] Preferably, the plurality of pressure zones include a first pressure zone, a second pressure zone, a third pressure zone, a fourth pressure zone, a fifth pressure zone, and a sixth pressure zone arranged sequentially along the running direction of the base membrane and the mother membrane, wherein the pressure in the first pressure zone increases sequentially to the third pressure zone, and the pressure in the third pressure zone decreases sequentially to the sixth pressure zone.

[0008] Preferably, the pressure in the first pressure zone is set to 0.3-0.5N, the pressure in the second pressure zone is set to 0.5-0.8N, the pressure in the third pressure zone is set to 0.8-1.0N, the pressure in the fourth pressure zone is set to 0.6-0.8N, the pressure in the fifth pressure zone is set to 0.4-0.6N, and the pressure in the sixth pressure zone is set to 0.3-0.4N.

[0009] Preferably, in step S3, the hot press roller structure includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. Each of the six sets of hot press roller units is connected to a cavity constant temperature heating system, a pressure closed-loop control system, and a synchronous transmission mechanism. The six sets of hot press roller units include a first hot press roller group, a second hot press roller group, a third hot press roller group, a fourth hot press roller group, a fifth hot press roller group, and a sixth hot press roller group. The first hot press roller group, the fourth hot press roller group, and the fifth hot press roller group all include rubber rollers and steel rollers. The rubber rollers are positioned above the steel rollers. The second hot press roller group, the third hot press roller group, and the sixth hot press roller group all include two steel rollers arranged vertically. The base film and the mother film are sequentially hot-pressed and formed by the six sets of hot press roller units.

[0010] Preferably, the hot press roller structure includes a central pressure-bearing main roller and six pressure rollers arranged sequentially around the central pressure-bearing main roller along the running direction of the base film and mother film. The temperature of the six pressure rollers decreases sequentially along the running direction, and the pressure of the six pressure rollers first increases and then decreases along the running direction. The temperatures of the six pressure rollers are sequentially set to 145-150℃, 140-145℃, 135-140℃, 130-135℃, 125-130℃, and 120-125℃; the pressures of the six pressure rollers are sequentially set to 0.3-0.5N, 0.5-0.8N, 0.8-1.0N, 0.6-0.8N, 0.4-0.6N, and 0.3-0.4N; the six pressure rollers sequentially include a rubber roller, a steel roller, a steel roller, a rubber roller, a rubber roller, and a steel roller. All six pressure rollers and the central pressure-bearing main roller are connected to a cavity constant temperature heating system, a pressure closed-loop control system, and a synchronous transmission mechanism.

[0011] Preferably, in step S1, the tension of both the base film and the mother film is set to 15-30N, the deviation is set to less than or equal to ±2N, the unwinding speed is set to 5-20m / min, and the unwinding correction accuracy is set to ±0.1mm; the base film is a modified TPU base film, the softening point of which is 100-125℃ and the Tg is 40-50℃; the surface of the mother film is provided with a microstructure with precision micron-level grooves, the groove height is 30-80μm, the mother film carrier is a PET, PE, or TPU film, and the surface of the mother film is pre-coated with a silicon-based or fluorine-based release layer or a hard anti-stick coating, the coating thickness is 50-150nm, and the structural accuracy is ±0.5nm.

[0012] Preferably, in step S2, an integrated upper and lower infrared heating device is used for preheating and softening. The preheating temperature is set to 120-150℃, the heating zone length of the integrated upper and lower infrared heating device is set to 1.0-1.5m, the preheating time is set to 3-6s, and the transverse temperature difference between the base film and the mother film surface is ≤±2℃.

[0013] Preferably, in step S4, cooling and shaping are performed by setting up three sets of water-cooled cooling roller units. All three sets of water-cooled cooling roller units are connected to a constant-temperature water circulation system, with a temperature accuracy set to ±0.5℃. Specific steps include: a1. Rapid cooling, with the water-cooled cooling roller unit temperature set at 20-30℃; a2. Deep cooling, wherein the temperature of the water-cooled cooling roller unit is set to 10-20℃; a3. Temperature stabilizes, with the water-cooled cooling roller unit temperature set at 20-30℃.

[0014] Preferably, step S5 includes: b1. Peel off the mother film at an angle of 30-45° and a peeling tension of 10-20N. The mother film winding speed should be the same as the cooling speed. b2. The winding is performed by installing a dual-station finished product winding machine, which is equipped with a constant tension control system, a film surface cleaning device and an electrostatic eliminator; the winding tension is set to 15-25N, the winding correction accuracy is ±0.1mm, and the flatness of the finished roll end face is ≤±1mm.

[0015] Compared with the prior art, the beneficial effects of the present invention are: This microstructure molding and preparation process based on elastomeric membrane materials adopts a "thermal softening state synchronous pressing" process to ensure that the base film is in the optimal rheological state for microstructure replication, achieving ultra-high fidelity and extremely low pressure; and adopts a multi-roll pressing mechanism to complete the replication and shaping of the continuously fed base film and mother film under multi-roll progressive pressure. The overall device is compact and occupies a small area. Utilizing the natural flattening effect of the roller system, it significantly improves the overall flatness of the film after lamination. A "heating-lamination integrated uniform temperature field cavity" is designed, ensuring that the mother film and base film are synchronously and uniformly preheated to a precise temperature before entering the lamination zone, guaranteeing the consistency of the replicated structure from the outset. Crucially, this invention divides the hot-pressing roller structure into multiple temperature and pressure zones along the film's running direction, employing a synergistic gradient control strategy of progressively decreasing temperature and initially increasing then decreasing pressure. This allows the base film to sequentially undergo a complete molding cycle: high-temperature, low-pressure filling; medium-temperature, medium-pressure shaping; and low-temperature, low-pressure depressurization. This achieves precise control of the entire process from filling and shaping to demolding of the microstructure. Test data from various embodiments show that this segmented temperature and pressure synergistic control has significant advantages over single temperature and pressure or simple linear temperature and pressure schemes, achieving optimal levels of structural replication accuracy (structural height 55.1 μm, top width 3.1 μm) and product yield. Attached Figure Description

[0016] Figure 1 This is a process flow diagram of an embodiment of the series roller structure of the present invention; Figure 2 This is a process flow diagram of the implementation scheme of the central pressure-bearing main roller structure of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0019] In the description of this patent, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integrated connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this patent according to the specific circumstances.

[0020] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a number" means two or more, unless otherwise explicitly specified.

[0021] Example 1 Please see Figure 1 As shown, the present invention provides a microstructure forming and preparation process based on elastomeric membrane materials, the preparation process including: S1. Unwinding of the base film and mother film: The tension of both the base film and mother film is set to 25N, the deviation is set to ±2N, the unwinding linear speed is set to 13m / min, and the unwinding correction accuracy is set to ±0.1mm. The base film is a modified TPU base film, including a softening point of 100-125℃ and a Tg of 40-50℃. The surface of the mother film is provided with a microstructure with precision micron-level grooves, the groove height is 30-80μm, the mother film carrier is a PET, PE or TPU film, and the surface of the mother film is pre-coated with a silicon-based or fluorine-based release layer or a hard anti-stick coating with a coating thickness of 50-150nm and a structural accuracy of ±0.5nm.

[0022] S2. Preheat and soften the base film and mother film using an integrated upper and lower infrared heating device. The preheating temperature is set to 135℃, the heating zone length of the integrated upper and lower infrared heating device is set to 1.4m, the preheating time is set to 4s, and the transverse temperature difference between the base film and mother film surfaces is ≤±2℃.

[0023] S3. Hot pressing is performed using a hot press roller structure, which includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. Each of the six sets of hot press roller units is connected to a constant temperature heating system for the cavity, a pressure closed-loop control system, and a synchronous transmission mechanism. The six sets of hot press roller units include a first set of hot press rollers, a second set of hot press rollers, a third set of hot press rollers, a fourth set of hot press rollers, a fifth set of hot press rollers, and a sixth set of hot press rollers. The first set of hot press rollers, the fourth set of hot press rollers, and the fifth set of hot press rollers all include rubber rollers and steel rollers, with the rubber rollers positioned above the steel rollers. The second set of hot press rollers, the third set of hot press rollers, and the sixth set of hot press rollers all include two steel rollers arranged vertically. The base film and the mother film are hot pressed sequentially through the six sets of hot press roller units.

[0024] The hot press roller structure has multiple temperature zones and multiple pressure zones arranged sequentially along the running direction of the base film and the mother film. The temperature of each temperature zone decreases step by step along the running direction, and the pressure of each pressure zone first increases and then decreases along the running direction. The gradient forming of the microstructure is achieved through the coordinated control of segmented temperature and segmented pressure. Multiple temperature zones are arranged sequentially along the running direction of the base membrane and the mother membrane: The temperature zones are: a first temperature zone of 145℃, a second temperature zone of 140℃, a third temperature zone of 135℃, a fourth temperature zone of 130℃, a fifth temperature zone of 125℃, and a sixth temperature zone of 120℃. Multiple pressure zones are arranged sequentially along the running direction of the base membrane and the mother membrane: The pressure zones are: a first pressure zone with a pressure of 0.3 N, a second pressure zone with a pressure of 0.5 N, a third pressure zone with a pressure of 0.8 N, a fourth pressure zone with a pressure of 0.6 N, a fifth pressure zone with a pressure of 0.4 N, and a sixth pressure zone with a pressure of 0.3 N. The pressure in the first pressure zone increases sequentially from the third pressure zone to the sixth pressure zone, and the pressure in the third pressure zone decreases sequentially from the sixth pressure zone to the first pressure zone.

[0025] S4. Cooling and shaping: Three sets of water-cooled cooling roller units are used for cooling and shaping. All three sets of water-cooled cooling roller units are connected to a constant-temperature water circulation system, with a temperature accuracy set to ±0.5℃. Specific steps include: a1. Rapid cooling, with the water-cooled cooling roller unit temperature set at 30℃; a2. Deep cooling, wherein the temperature of the water-cooled cooling roller unit is set to 10℃; a3. Temperature stabilizes, with the water-cooled cooling roller unit temperature set at 20℃.

[0026] S5. Peel off the mother film and wind it up, including: b1. Peel off the mother film at an angle of 30-45° and a peeling tension of 10-20N. The mother film winding speed should be the same as the cooling speed. b2. The winding is performed by installing a dual-station finished product winding machine, which is equipped with a constant tension control system, a film surface cleaning device and an electrostatic eliminator; the winding tension is set to 15-25N, the winding correction accuracy is ±0.1mm, and the flatness of the finished roll end face is ≤±1mm.

[0027] Example 2 Please see Figure 1 As shown, the present invention provides a microstructure forming and preparation process based on elastomeric membrane materials, the preparation process including: S1. Unwinding of the base film and mother film: The tension of both the base film and mother film is set to 25N, the deviation is set to ±2N, the unwinding linear speed is set to 13m / min, and the unwinding correction accuracy is set to ±0.1mm. The base film is a modified TPU base film, including a softening point of 100-125℃ and a Tg of 40-50℃. The surface of the mother film is provided with a microstructure with precision micron-level grooves, the groove height is 30-80μm, the mother film carrier is a PET, PE or TPU film, and the surface of the mother film is pre-coated with a silicon-based or fluorine-based release layer or a hard anti-stick coating with a coating thickness of 50-150nm and a structural accuracy of ±0.5nm.

[0028] S2. Preheat and soften the base film and mother film using an integrated upper and lower infrared heating device. The preheating temperature is set to 135℃, the heating zone length of the integrated upper and lower infrared heating device is set to 1.4m, the preheating time is set to 4s, and the transverse temperature difference between the base film and mother film surfaces is ≤±2℃.

[0029] S3. Hot pressing is performed using a hot press roller structure, which includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. Each of the six sets of hot press roller units is connected to a constant temperature heating system for the cavity, a pressure closed-loop control system, and a synchronous transmission mechanism. The six sets of hot press roller units include a first set of hot press rollers, a second set of hot press rollers, a third set of hot press rollers, a fourth set of hot press rollers, a fifth set of hot press rollers, and a sixth set of hot press rollers. The first set of hot press rollers, the fourth set of hot press rollers, and the fifth set of hot press rollers all include rubber rollers and steel rollers, with the rubber rollers positioned above the steel rollers. The second set of hot press rollers, the third set of hot press rollers, and the sixth set of hot press rollers all include two steel rollers arranged vertically. The base film and the mother film are hot pressed sequentially through the six sets of hot press roller units.

[0030] The hot press roller structure has multiple temperature zones and multiple pressure zones arranged sequentially along the running direction of the base film and the mother film. The temperature of each temperature zone decreases step by step along the running direction, and the pressure of each pressure zone first increases and then decreases along the running direction. The gradient forming of the microstructure is achieved through the coordinated control of segmented temperature and segmented pressure. Multiple temperature zones are arranged sequentially along the running direction of the base membrane and the mother membrane: The temperature zones are: a first temperature zone of 148℃, a second temperature zone of 144℃, a third temperature zone of 138℃, a fourth temperature zone of 133℃, a fifth temperature zone of 127℃, and a sixth temperature zone of 122℃. Multiple pressure zones are arranged sequentially along the running direction of the base membrane and the mother membrane: The pressure zones are: a first pressure zone with a pressure of 0.4 N, a second pressure zone with a pressure of 0.7 N, a third pressure zone with a pressure of 0.9 N, a fourth pressure zone with a pressure of 0.7 N, a fifth pressure zone with a pressure of 0.5 N, and a sixth pressure zone with a pressure of 0.3 N. The pressure in the first pressure zone increases sequentially from the third pressure zone to the sixth pressure zone, and the pressure in the third pressure zone decreases sequentially from the sixth pressure zone to the first pressure zone.

[0031] S4. Cooling and shaping: Three sets of water-cooled cooling roller units are used for cooling and shaping. All three sets of water-cooled cooling roller units are connected to a constant-temperature water circulation system, with a temperature accuracy set to ±0.5℃. Specific steps include: a1. Rapid cooling, with the water-cooled cooling roller unit temperature set at 30℃; a2. Deep cooling, wherein the temperature of the water-cooled cooling roller unit is set to 10℃; a3. Temperature stabilizes, with the water-cooled cooling roller unit temperature set at 20℃.

[0032] S5. Peel off the mother film and wind it up, including: b1. Peel off the mother film at an angle of 30-45° and a peeling tension of 10-20N. The mother film winding speed should be the same as the cooling speed. b2. The winding is performed by installing a dual-station finished product winding machine, which is equipped with a constant tension control system, a film surface cleaning device and an electrostatic eliminator; the winding tension is set to 15-25N, the winding correction accuracy is ±0.1mm, and the flatness of the finished roll end face is ≤±1mm.

[0033] Example 3 Please see Figure 1 As shown, the present invention provides a microstructure forming and preparation process based on elastomeric membrane materials, the preparation process including: S1. Unwinding of the base film and mother film: The tension of both the base film and mother film is set to 25N, the deviation is set to ±2N, the unwinding linear speed is set to 13m / min, and the unwinding correction accuracy is set to ±0.1mm. The base film is a modified TPU base film, including a softening point of 100-125℃ and a Tg of 40-50℃. The surface of the mother film is provided with a microstructure with precision micron-level grooves, the groove height is 30-80μm, the mother film carrier is a PET, PE or TPU film, and the surface of the mother film is pre-coated with a silicon-based or fluorine-based release layer or a hard anti-stick coating with a coating thickness of 50-150nm and a structural accuracy of ±0.5nm.

[0034] S2. Preheat and soften the base film and mother film using an integrated upper and lower infrared heating device. The preheating temperature is set to 135℃, the heating zone length of the integrated upper and lower infrared heating device is set to 1.4m, the preheating time is set to 4s, and the transverse temperature difference between the base film and mother film surfaces is ≤±2℃.

[0035] S3. Hot pressing is performed using a hot press roller structure, which includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. Each of the six sets of hot press roller units is connected to a constant temperature heating system for the cavity, a pressure closed-loop control system, and a synchronous transmission mechanism. The six sets of hot press roller units include a first set of hot press rollers, a second set of hot press rollers, a third set of hot press rollers, a fourth set of hot press rollers, a fifth set of hot press rollers, and a sixth set of hot press rollers. The first set of hot press rollers, the fourth set of hot press rollers, and the fifth set of hot press rollers all include rubber rollers and steel rollers, with the rubber rollers positioned above the steel rollers. The second set of hot press rollers, the third set of hot press rollers, and the sixth set of hot press rollers all include two steel rollers arranged vertically. The base film and the mother film are hot pressed sequentially through the six sets of hot press roller units.

[0036] The hot press roller structure has multiple temperature zones and multiple pressure zones arranged sequentially along the running direction of the base film and the mother film. The temperature of each temperature zone decreases step by step along the running direction, and the pressure of each pressure zone first increases and then decreases along the running direction. The gradient forming of the microstructure is achieved through the coordinated control of segmented temperature and segmented pressure. Multiple temperature zones are arranged sequentially along the running direction of the base membrane and the mother membrane: The temperature zones are: a first temperature zone of 150℃, a second temperature zone of 145℃, a third temperature zone of 140℃, a fourth temperature zone of 135℃, a fifth temperature zone of 130℃, and a sixth temperature zone of 125℃. Multiple pressure zones are arranged sequentially along the running direction of the base membrane and the mother membrane: The pressure zones are: a first pressure zone with a pressure of 0.5 N, a second pressure zone with a pressure of 0.8 N, a third pressure zone with a pressure of 1.0 N, a fourth pressure zone with a pressure of 0.8 N, a fifth pressure zone with a pressure of 0.6 N, and a sixth pressure zone with a pressure of 0.4 N. The pressure in the first pressure zone increases sequentially from the third pressure zone to the sixth pressure zone, and the pressure in the third pressure zone decreases sequentially from the sixth pressure zone to the first pressure zone.

[0037] S4. Cooling and shaping: Three sets of water-cooled cooling roller units are used for cooling and shaping. All three sets of water-cooled cooling roller units are connected to a constant-temperature water circulation system, with a temperature accuracy set to ±0.5℃. Specific steps include: a1. Rapid cooling, with the water-cooled cooling roller unit temperature set at 30℃; a2. Deep cooling, wherein the temperature of the water-cooled cooling roller unit is set to 10℃; a3. Temperature stabilizes, with the water-cooled cooling roller unit temperature set at 20℃.

[0038] S5. Peel off the mother film and wind it up, including: b1. Peel off the mother film at an angle of 30-45° and a peeling tension of 10-20N. The mother film winding speed should be the same as the cooling speed. b2. The winding is performed by installing a dual-station finished product winding machine, which is equipped with a constant tension control system, a film surface cleaning device and an electrostatic eliminator; the winding tension is set to 15-25N, the winding correction accuracy is ±0.1mm, and the flatness of the finished roll end face is ≤±1mm.

[0039] Example 4 Please see Figure 2 As shown, the present invention provides a microstructure forming and preparation process based on an elastomer membrane material, the preparation process including: S1. Unwinding of the base film and mother film: The tension of both the base film and mother film is set to 25N, the deviation is set to ±2N, the unwinding linear speed is set to 13m / min, and the unwinding correction accuracy is set to ±0.1mm. The base film is a modified TPU base film, including a softening point of 100-125℃ and a Tg of 40-50℃. The surface of the mother film is provided with a microstructure with precision micron-level grooves, the groove height is 30-80μm, the mother film carrier is a PET, PE or TPU film, and the surface of the mother film is pre-coated with a silicon-based or fluorine-based release layer or a hard anti-stick coating with a coating thickness of 50-150nm and a structural accuracy of ±0.5nm.

[0040] S2. Preheat and soften the base film and mother film using an integrated upper and lower infrared heating device. The preheating temperature is set to 135℃, the heating zone length of the integrated upper and lower infrared heating device is set to 1.4m, the preheating time is set to 4s, and the transverse temperature difference between the base film and mother film surfaces is ≤±2℃.

[0041] S3. Hot pressing is performed using a hot press roller structure. The hot press roller structure includes a central pressure-bearing main roller and six pressure rollers arranged sequentially around the central pressure-bearing main roller along the running direction of the base film and mother film. The temperature of the six pressure rollers decreases sequentially along the running direction, and the pressure of the six pressure rollers first increases and then decreases along the running direction. The six pressure rollers sequentially include a rubber roller, a steel roller, a steel roller, a rubber roller, a rubber roller, and a steel roller. All six pressure rollers and the central pressure-bearing main roller are connected to a cavity constant temperature heating system, a pressure closed-loop control system, and a synchronous transmission mechanism.

[0042] The hot press roller structure has multiple temperature zones and multiple pressure zones arranged sequentially along the running direction of the base film and the mother film. The temperature of each temperature zone decreases step by step along the running direction, and the pressure of each pressure zone first increases and then decreases along the running direction. The gradient forming of the microstructure is achieved through the coordinated control of segmented temperature and segmented pressure. Multiple temperature zones are arranged sequentially along the running direction of the base membrane and the mother membrane: The temperature zones are: a first temperature zone of 145℃, a second temperature zone of 140℃, a third temperature zone of 135℃, a fourth temperature zone of 130℃, a fifth temperature zone of 125℃, and a sixth temperature zone of 120℃. Multiple pressure zones are arranged sequentially along the running direction of the base membrane and the mother membrane: The pressure zones are: a first pressure zone with a pressure of 0.3 N, a second pressure zone with a pressure of 0.5 N, a third pressure zone with a pressure of 0.8 N, a fourth pressure zone with a pressure of 0.6 N, a fifth pressure zone with a pressure of 0.4 N, and a sixth pressure zone with a pressure of 0.3 N. The pressure in the first pressure zone increases sequentially from the third pressure zone to the sixth pressure zone, and the pressure in the third pressure zone decreases sequentially from the sixth pressure zone to the first pressure zone.

[0043] S4. Cooling and shaping: Three sets of water-cooled cooling roller units are used for cooling and shaping. All three sets of water-cooled cooling roller units are connected to a constant-temperature water circulation system, with a temperature accuracy set to ±0.5℃. Specific steps include: a1. Rapid cooling, with the water-cooled cooling roller unit temperature set at 30℃; a2. Deep cooling, wherein the temperature of the water-cooled cooling roller unit is set to 10℃; a3. Temperature stabilizes, with the water-cooled cooling roller unit temperature set at 20℃.

[0044] S5. Peel off the mother film and wind it up, including: b1. Peel off the mother film at an angle of 30-45° and a peeling tension of 10-20N. The mother film winding speed should be the same as the cooling speed. b2. The winding is performed by installing a dual-station finished product winding machine, which is equipped with a constant tension control system, a film surface cleaning device and an electrostatic eliminator; the winding tension is set to 15-25N, the winding correction accuracy is ±0.1mm, and the flatness of the finished roll end face is ≤±1mm.

[0045] Comparative Example 1 Steps S1, S2, S4, and S5 are the same as in Example 1.

[0046] Step S3: Hot pressing is performed using a hot press roller structure. The hot press roller structure includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. The six sets of hot press roller units include a first hot press roller group, a second hot press roller group, a third hot press roller group, a fourth hot press roller group, a fifth hot press roller group, and a sixth hot press roller group. The first, fourth, and fifth hot press roller groups all include rubber rollers and steel rollers, with the rubber rollers positioned above the steel rollers. The second, third, and sixth hot press roller groups all include two steel rollers arranged vertically. The base film and the mother film are sequentially hot pressed through the six sets of hot press roller units.

[0047] The set temperatures are 140℃, 138℃, 132℃, 125℃, 124℃ and 118℃ respectively; The pressures are set to 0.2N, 0.3N, 0.5N, 0.5N, 0.3N, and 0.2N.

[0048] Comparative Example 2 Steps S1, S2, S4, and S5 are the same as in Example 1.

[0049] Step S3: Hot pressing is performed using a hot press roller structure. The hot press roller structure includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. The six sets of hot press roller units include a first hot press roller group, a second hot press roller group, a third hot press roller group, a fourth hot press roller group, a fifth hot press roller group, and a sixth hot press roller group. The first, fourth, and fifth hot press roller groups all include rubber rollers and steel rollers, with the rubber rollers positioned above the steel rollers. The second, third, and sixth hot press roller groups all include two steel rollers arranged vertically. The base film and the mother film are sequentially hot pressed through the six sets of hot press roller units.

[0050] The set temperatures are 151℃, 147℃, 142℃, 136℃, 131℃ and 127℃ respectively; The pressure settings are 0.7N, 1.0N, 1.2N, 1.0N, 0.8N, and 0.5N.

[0051] Comparative Example 3 Steps S1, S2, S4, and S5 are the same as in Example 1.

[0052] Step S3: Hot pressing is performed using a hot press roller structure. The hot press roller structure includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. The six sets of hot press roller units include a first hot press roller group, a second hot press roller group, a third hot press roller group, a fourth hot press roller group, a fifth hot press roller group, and a sixth hot press roller group. The first, fourth, and fifth hot press roller groups all include rubber rollers and steel rollers, with the rubber rollers positioned above the steel rollers. The second, third, and sixth hot press roller groups all include two steel rollers arranged vertically. The base film and the mother film are sequentially hot pressed through the six sets of hot press roller units.

[0053] The set temperatures are 145℃, 140℃, 130℃, 130℃, 125℃ and 120℃ respectively; The pressure settings are 0.3N, 0.5N, 1.2N, 0.6N, 0.4N, and 0.3N.

[0054] Comparative Example 4 Steps S1, S2, S4, and S5 are the same as in Example 1.

[0055] Step S3: Hot pressing is performed using a hot press roller structure. The hot press roller structure includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. The six sets of hot press roller units include a first hot press roller group, a second hot press roller group, a third hot press roller group, a fourth hot press roller group, a fifth hot press roller group, and a sixth hot press roller group. The first, fourth, and fifth hot press roller groups all include rubber rollers and steel rollers, with the rubber rollers positioned above the steel rollers. The second, third, and sixth hot press roller groups all include two steel rollers arranged vertically. The base film and the mother film are sequentially hot pressed through the six sets of hot press roller units.

[0056] The set temperatures are 155℃, 145℃, 140℃, 135℃, 120℃ and 120℃ respectively; The pressure settings are 0.3N, 0.5N, 0.8N, 0.6N, 0.4N, and 0.3N.

[0057] Comparative Example 5 Steps S1, S2, S4, and S5 are the same as in Example 1.

[0058] Step S3: Hot pressing is performed using a hot press roller structure. The hot press roller structure includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. The six sets of hot press roller units include a first hot press roller group, a second hot press roller group, a third hot press roller group, a fourth hot press roller group, a fifth hot press roller group, and a sixth hot press roller group. The first, fourth, and fifth hot press roller groups all include rubber rollers and steel rollers, with the rubber rollers positioned above the steel rollers. The second, third, and sixth hot press roller groups all include two steel rollers arranged vertically. The base film and the mother film are sequentially hot pressed through the six sets of hot press roller units.

[0059] The set temperatures are 145℃, 140℃, 135℃, 130℃, 125℃ and 120℃ respectively; The pressure settings are 0.3N, 1.0N, 0.8N, 0.6N, 0.8N, and 0.3N.

[0060] Table 1

[0061] Table 2

[0062] Examples 1-4 all meet the product standard requirements. All four embodiments met the standards in four aspects: structural height (55.1-55.5μm, standard 55μm±2μm), structural top width (3.1-3.6μm, standard 3μm±1μm), product thickness (187.2-188.0μm, standard 188μm±5μm), and appearance (all are flat and wrinkle-free, structurally intact and unbroken).

[0063] Example 3 showed the best performance, with a structure height of 55.1 μm and a top width of 3.1 μm, close to the theoretical target values. Both temperature and pressure were set to the upper limits of their respective ranges (decreasing stepwise from 150℃ to 125℃, and increasing first and then decreasing from 0.5N to 1.0N to 0.4N), indicating that within the process window defined by this invention, appropriately increasing the temperature and pressure levels is beneficial for the full filling and precise shaping of the microstructure.

[0064] The temperature and pressure values ​​in Examples 1 and 4 are exactly the same (145℃→120℃, 0.3N→0.8N→0.3N), but Example 1 uses 6 sets of tandem hot press roller units, while Example 4 uses a central pressure main roller + 6 pressure rollers structure. Both meet the performance standards and are very similar (structural height 54.0μm vs 55.5μm, top width 3.6μm vs 3.3μm), fully demonstrating that the segmented temperature and pressure coordinated control strategy of this invention has universality and good process transferability for different hot press roller structures.

[0065] The temperature and pressure of Comparative Example 1 were generally too low. The temperatures of the six temperature zones were 140℃, 138℃, 132℃, 125℃, 124℃, and 118℃, all lower than the lower limit of the temperature range (120-145℃) specified in this invention. The pressures of the first to third pressure zones (0.2N, 0.3N, and 0.5N) were also too low. Under these process conditions, the modified TPU base film failed to reach the optimal rheological softening state at the hot pressing station due to insufficient preheating and low molding temperature, resulting in insufficient melt filling driving force and incomplete microstructure replication. The measured structure height was only 38.6μm (standard 55μm), the top width was 8.2μm (standard 3μm), and the product thickness was 169.5μm (standard 188μm), all three core dimensions were unqualified. This comparative example demonstrates that excessively low temperature leads to insufficient softening of the base film, and excessively low pressure results in insufficient filling driving force; when these two factors are combined, faithful replication of the microstructure cannot be achieved.

[0066] The temperature and pressure of Comparative Example 2 were generally too high. The temperatures in the six temperature zones were 151℃, 147℃, 142℃, 136℃, 131℃, and 127℃, all exceeding the upper temperature limit (120-150℃) specified in this invention. The pressures in the first to third pressure zones were 0.7N, 1.0N, and 1.2N, respectively, far exceeding the reasonable range. Excessive temperature caused an excessive decrease in the viscosity of the base film melt, resulting in excessive fluidity and loss of material flow stability. Excessive pressure caused excessive compression or even crushing of the filled structure. The measured product surface showed numerous indentations and wrinkles, structural fractures, a structural height of only 28.1μm (significantly reduced to the standard value), and a product thickness of 167.5μm (substandard). This comparative example demonstrates that excessive temperature leads to uneven material flow, surface ripples, and even wrinkles, while excessive pressure crushes the microstructure; both cause irreversible damage to product performance.

[0067] Comparative Example 3 exhibits localized pressure anomalies. The temperatures in all six temperature zones are identical to those in Example 1. The pressure in zones one through six is ​​also consistent with Example 1, but the pressure in zone three surges to 1.2 N (compared to 0.8 N in Example 1). While the overall pressure distribution shows an initial increase followed by a decrease, the peak pressure of 1.2 N far exceeds the reasonable upper limit of 0.8-1.0 N. Excessive pressure at the third station causes over-compression of the initially formed microstructure, resulting in slight indentations and wrinkles on the product surface. The structure height of 52.6 μm is too low, and the top width of 4.5 μm is too wide, failing to meet dimensional standards. This comparative example demonstrates that the magnitude of the pressure peak has a crucial impact on the final molding accuracy. Exceeding the upper limit of the pressure range defined in this invention will lead to partial crushing of the microstructure and a decrease in fidelity.

[0068] The temperature sequence in Comparative Example 4 is disordered. The six temperature zones are 155℃, 145℃, 140℃, 135℃, 120℃, and 120℃, respectively, exhibiting several problems: the first temperature zone (155℃) exceeds the upper limit; the temperature drop from the fifth to the sixth temperature zone is 0 (120℃→120℃), and the temperature drop from the fourth to the fifth temperature zone reaches 15℃ (135℃→120℃), completely deviating from the "gradually decreasing" temperature distribution pattern. This disordered temperature gradient causes the base film to experience severe temperature shocks of "overheating → sudden cooling" along the operating direction, resulting in uncontrolled thermal history, uneven cooling rates, and ultimately, obvious wavy lines appearing on the product surface. Although the structural height of 55.2μm and the top width of 3.1μm unexpectedly meet the standards, the appearance is still deemed unacceptable. This comparative example demonstrates that the "gradual decrease" of temperature is not an optional modification, but a key process constraint to ensure the flatness of the product's appearance. Zero temperature drop or excessive temperature drop will disrupt the uniformity of the temperature field during the hot pressing process.

[0069] The pressure sequence in Comparative Example 5 was disordered. The temperatures in the six temperature zones were exactly the same as in Example 1, but the pressure distribution was 0.3N, 1.0N, 0.8N, 0.6N, 0.8N, and 0.3N, exhibiting a fluctuating pattern of "increase → decrease → increase," severely violating the single-peak rule of "increase first, then decrease." The second pressure zone of 1.0N exceeded the upper limit, and the fifth pressure zone of 0.8N abnormally rebounded after decreasing in the fourth zone, disrupting the gradual loading-unloading pressure path required for microstructure formation. This pressure sequence caused repeated "loading-unloading-reloading" alternating stress on the base film, resulting in secondary extrusion deformation of the formed structure at subsequent processing stations. The measured structure height was only 32.5μm (severely below standard), with numerous indentations and wrinkles on the surface, partial structural fracture, and a product thickness of 165.8μm (far below the 188μm standard). This comparative example demonstrates that the single-peak distribution of pressure along the operating direction, characterized by "increasing first and then decreasing," is the core process logic ensuring that the microstructure undergoes the complete molding cycle of "filling → holding pressure → releasing pressure." Repeated pressure fluctuations will disrupt the stress history of the microstructure, leading to a significant reduction in structural height. Further cross-comparison with Example 1 (0.3N→0.5N→0.8N→0.6N→0.4N→0.3N, strictly symmetrical single peak) shows that the third pressure zone, as the peak zone (0.8N), precisely matches the intermediate temperature (135℃) of the third temperature zone. The two work together to form the optimal process coupling window for the microstructure's "fully filled → precisely shaped" process. Disorder of any parameter will prevent the achievement of this effect.

[0070] Base film thickness: 150μm Product standards: Product thickness 188±5μm, structural height 55μm±2μm, top edge width 3μm±1μm, product appearance flat and wrinkle-free, structural integrity without breakage. Influencing factors: Excessive temperature causes uneven feeding of the film product, resulting in wavy lines on the surface; insufficient temperature causes the softening point of the product to be below standard, resulting in substandard structural dimensions after hot pressing; excessive pressure causes wrinkles on the product surface, the structure to be compressed, and the size to become smaller; insufficient pressure causes the size to be substandard and smaller.

[0071] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A microstructure fabrication process based on elastomeric membrane materials, characterized in that: The preparation process includes: S1. Unwinding of the base film and mother film; S2. Preheat and soften the base film and mother film; S3. Hot pressing is performed by a hot press roller structure. The hot press roller structure is provided with multiple temperature zones and multiple pressure zones in sequence along the running direction of the base film and the mother film. The temperature of each temperature zone decreases step by step along the running direction, and the pressure of each pressure zone increases first and then decreases along the running direction. Gradient forming of microstructure is achieved by the coordinated control of segmented temperature and segmented pressure. S4, Cooling and molding; S5. Peel off the mother film and roll it up.

2. The microstructure forming and preparation process based on elastomeric membrane material according to claim 1, characterized in that: The multiple temperature zones include a first temperature zone, a second temperature zone, a third temperature zone, a fourth temperature zone, a fifth temperature zone, and a sixth temperature zone arranged sequentially along the running direction of the base film and the mother film, with the temperature of the first temperature zone decreasing sequentially to the sixth temperature zone.

3. The microstructure forming and preparation process based on elastomeric membrane material according to claim 2, characterized in that: The temperature of the first temperature zone is set to 145-150℃, the temperature of the second temperature zone is set to 140-145℃, the temperature of the third temperature zone is set to 135-140℃, the temperature of the fourth temperature zone is set to 130-135℃, the temperature of the fifth temperature zone is set to 125-130℃, and the temperature of the sixth temperature zone is set to 120-125℃.

4. The microstructure forming and preparation process based on elastomeric membrane material according to claim 1, characterized in that: The plurality of pressure zones include a first pressure zone, a second pressure zone, a third pressure zone, a fourth pressure zone, a fifth pressure zone, and a sixth pressure zone arranged sequentially along the running direction of the base membrane and the mother membrane. The pressure in the first pressure zone increases sequentially to the third pressure zone, and the pressure in the third pressure zone decreases sequentially to the sixth pressure zone.

5. The microstructure forming and preparation process based on elastomeric membrane material according to claim 4, characterized in that: The pressure in the first pressure zone is set to 0.3-0.5N, the pressure in the second pressure zone is set to 0.5-0.8N, the pressure in the third pressure zone is set to 0.8-1.0N, the pressure in the fourth pressure zone is set to 0.6-0.8N, the pressure in the fifth pressure zone is set to 0.4-0.6N, and the pressure in the sixth pressure zone is set to 0.3-0.4N.

6. The microstructure forming and preparation process based on elastomeric membrane material according to claim 2, characterized in that: In step S3, the hot press roller structure includes six sets of hot press roller units arranged sequentially along the running direction of the base film and the mother film. Each of the six sets of hot press roller units is connected to a cavity constant temperature heating system, a pressure closed-loop control system, and a synchronous transmission mechanism. The six sets of hot press roller units include a first hot press roller group, a second hot press roller group, a third hot press roller group, a fourth hot press roller group, a fifth hot press roller group, and a sixth hot press roller group. The first hot press roller group, the fourth hot press roller group, and the fifth hot press roller group all include rubber rollers and steel rollers. The rubber rollers are positioned above the steel rollers. The second hot press roller group, the third hot press roller group, and the sixth hot press roller group all include two steel rollers arranged vertically. The base film and the mother film are sequentially hot-pressed and formed by the six sets of hot press roller units.

7. The microstructure forming and preparation process based on elastomeric membrane material according to claim 1, characterized in that: The hot press roller structure includes a central pressure-bearing main roller and six pressure rollers arranged sequentially around the central pressure-bearing main roller along the running direction of the base film and mother film. The temperature of the six pressure rollers decreases sequentially along the running direction, and the pressure of the six pressure rollers first increases and then decreases along the running direction. The temperatures of the six pressure rollers are set sequentially to 145-150℃, 140-145℃, 135-140℃, 130-135℃, 125-130℃, and 120-125℃; the pressures of the six pressure rollers are set sequentially to 0.3-0.5N, 0.5-0.8N, 0.8-1.0N, 0.6-0.8N, 0.4-0.6N, and 0.3-0.4N; the six pressure rollers sequentially include a rubber roller, a steel roller, a steel roller, a rubber roller, a rubber roller, and a steel roller. All six pressure rollers and the central pressure-bearing main roller are connected to a cavity constant temperature heating system, a pressure closed-loop control system, and a synchronous transmission mechanism.

8. The microstructure forming and preparation process based on elastomeric membrane material according to claim 1, characterized in that: In step S1, the tension of both the base film and the mother film is set to 15-30N, the deviation is set to less than or equal to ±2N, the unwinding speed is set to 5-20m / min, and the unwinding correction accuracy is set to ±0.1mm. The base film is a modified TPU base film with a softening point of 100-125℃ and a Tg of 40-50℃. The surface of the mother film is provided with a microstructure with precision micron-level grooves, the groove height is 30-80μm, the mother film carrier is a PET, PE, or TPU film, and the surface of the mother film is pre-coated with a silicon-based or fluorine-based release layer or a hard anti-stick coating with a coating thickness of 50-150nm and a structural accuracy of ±0.5nm.

9. The microstructure forming and preparation process based on elastomeric membrane material according to claim 1, characterized in that: In step S2, an integrated upper and lower infrared heating device is used for preheating and softening. The preheating temperature is set to 120-150℃, the heating zone length of the integrated upper and lower infrared heating device is set to 1.0-1.5m, the preheating time is set to 3-6s, and the transverse temperature difference between the base film and the mother film surface is ≤±2℃.

10. The microstructure forming and preparation process based on elastomeric membrane material according to claim 1, characterized in that: In step S4, three sets of water-cooled cooling roller units are set up for cooling and shaping. All three sets of water-cooled cooling roller units are connected to a constant-temperature water circulation system, with a temperature accuracy set to ±0.5℃. Specific steps include: a1. Rapid cooling, with the water-cooled cooling roller unit temperature set at 20-30℃; a2. Deep cooling, wherein the temperature of the water-cooled cooling roller unit is set to 10-20℃; a3. Temperature stabilizes, with the water-cooled cooling roller unit temperature set at 20-30℃.

11. The microstructure forming and preparation process based on elastomeric membrane material according to claim 1, characterized in that: Step S5 includes: b1. Peel off the mother film at an angle of 30-45° and a peeling tension of 10-20N. The mother film winding speed should be the same as the cooling speed. b2. The winding is performed by installing a dual-station finished product winding machine, which is equipped with a constant tension control system, a film surface cleaning device and an electrostatic eliminator; the winding tension is set to 15-25N, the winding correction accuracy is ±0.1mm, and the flatness of the finished roll end face is ≤±1mm.

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