Independent humidity control device for slit coating

Abstract

The invention relates to the technical field of slit coating, and discloses a slit coating independent humidity control device which comprises a base table, a local sealing cavity, a precise humidity adjusting module, a real-time feedback module, a solvent recovery auxiliary unit, a system control module and an airflow distribution device. The base platform supports and fixes the slit coating head and the local sealing cavity; the local sealing cavity is arranged around an outlet of the slit coating head and a coating transmission path and is fixed on the base station; the precise humidity adjusting module, the real-time feedback module and the solvent recovery auxiliary unit are all integrated on the local sealing cavity or the base station. By means of the design of the local sealing cavity, only the coating key area is subjected to humidity control, compared with an overall environment humidity control scheme, the energy consumption is reduced, large-size coating is adapted, and the expansibility is high, and the local sealing cavity can be flexibly adapted to an industrial-grade large-size coating head; the humidity is controlled more accurately, and the response time is shortened.

Description

Technical Field

[0001] This invention relates to the field of slot coating technology, specifically to a separate humidity control device for slot coating. Background Technology

[0002] Slit coating technology is a core process for fabricating high-precision functional thin films (such as perovskite active layers, OLED organic light-emitting layers, and solid-state battery electrolyte layers). It uses a precision slit nozzle to uniformly coat a precursor solution onto the surface of a substrate (rigid glass or flexible PET / PI). The coating quality (crystallinity, uniformity, defect rate) directly determines the final performance of the device. The fabrication of such functional thin films has stringent requirements regarding the local humidity environment: for example, perovskite precursors (such as CsO). 05 FA0. 85 MA0.1PbI3 needs to be coated at a humidity of 30-40%RH (too high humidity can easily cause the precursor to hydrolyze and generate PbI2 impurities, while too low humidity will cause the solvent to evaporate too quickly and lead to pinholes in the coating); the OLED organic transport layer needs a humidity of 50-60%RH to avoid film cracking; and the solid-state battery electrolyte layer needs a low humidity environment of less than 20%RH to prevent the electrolyte from absorbing moisture and failing.

[0003] Existing humidity control solutions for slot coating processes all adopt a "holistic environmental humidity control" approach. The core logic involves using a combination of central air conditioning, rotary dehumidifiers, and FFU (Fan Filter Unit) systems to regulate the environment of the entire coating workshop or clean area, typically maintaining the temperature at 20-25℃ and humidity within a wide range of 30%-60%RH to meet basic production needs. This solution was widely adopted in the early stages of process scaling due to its simple control logic and low equipment integration difficulty, especially suitable for traditional coating scenarios with lower humidity uniformity requirements. However, the lack of targeted humidity control structures for critical coating areas results in insurmountable bottlenecks in humidity control accuracy, energy consumption costs, and multi-station compatibility. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a separate humidity control device for slot coating, which solves the problem that the lack of a targeted humidity control structure for key coating areas leads to bottlenecks in humidity control accuracy, energy consumption cost, and multi-station compatibility.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a slot coating independent humidity control device, comprising a base, a locally sealed cavity, a precise humidity adjustment module, a real-time feedback module, a solvent recovery auxiliary unit, a system control module, and an airflow distribution device; the base supports and fixes the slot coating head and the locally sealed cavity; the locally sealed cavity is arranged around the outlet of the slot coating head and the coating transmission path, and is fixed on the base; the precise humidity adjustment module, the real-time feedback module, and the solvent recovery auxiliary unit are all integrated into the locally sealed cavity or the base; the airflow distribution device is disposed inside the locally sealed cavity for guiding and uniformly distributing the humidity-controlled airflow; the system control module is electrically connected to the precise humidity adjustment module, the real-time feedback module, and the solvent recovery auxiliary unit respectively; the system control module has a built-in humidity deviation compensation algorithm module, pre-stores the humidity interference coefficients corresponding to different precursor solvents, and can receive humidity detection data transmitted by the real-time feedback module, calculate the humidity compensation amount, and send it to the precise humidity adjustment module.

[0006] Preferably, the real-time feedback module is configured to execute a predictive control algorithm based on a humidity-solvent evaporation coupling model. By collecting data on the coating speed, precursor solution evaporation rate, and airflow velocity within the cavity in real time, it predicts future humidity trends and adjusts the power of the dehumidification or humidification unit in advance to counteract the main interference of solvent evaporation on humidity. The real-time feedback module includes two humidity sensors, a controller, and a solvent concentration sensor. The two humidity sensors are respectively located on both sides of the coating transmission path and are both electrically connected to the controller. The controller is electrically connected to the micro dehumidification unit and the micro humidification unit, respectively.

[0007] Preferably, the real-time feedback module further includes a micro-pressure monitoring unit inside the cavity. The controller maintains a slight positive pressure inside the cavity to prevent external ambient air from infiltrating, and uses air pressure as an auxiliary variable to participate in the closed-loop feedback of humidity control. The data filtering submodule of the controller uses a moving average filtering algorithm to process the real-time humidity data collected by the two humidity sensors, filtering out instantaneous interference signals with a frequency less than the minimum value, and the size of the filtering window can be set by the system control module.

[0008] Preferably, the material of the partially sealed cavity is transparent polycarbonate, and the two ends of the partially sealed cavity are provided with openings adapted to the coating transmission path. A flexible sealing gasket is provided at the opening, and the flexible sealing gasket is attached to the surface of the substrate. The precise humidity adjustment module includes a micro dehumidification unit, a micro humidification unit and an airflow distribution plate. The micro dehumidification unit and the micro humidification unit are arranged side by side, and the airflow distribution plate is disposed on the side wall of the partially sealed cavity and covers the air outlet side of the micro dehumidification unit and the micro humidification unit.

[0009] Preferably, the airflow distribution plate is made of porous ceramic material, and its area is adapted to the inner wall area of ​​the local sealing cavity. The air outlet direction of the airflow distribution plate is set at an angle of 30-60° with the coating transmission direction. The airflow distribution device includes multiple sets of independently adjustable airflow nozzles. The outlet angle and flow rate of each set of nozzles can be adjusted by the system control module to fine-tune the humidity at different locations in the coating area. The airflow coverage width is consistent with the coating width.

[0010] Preferably, the solvent recovery auxiliary unit includes a micro vacuum pump and an activated carbon adsorption device. The micro vacuum pump and the activated carbon adsorption device are connected by a pipeline. The micro vacuum pump is located on both sides of the locally sealed cavity. There are two solvent recovery auxiliary units, which are symmetrically arranged on both sides of the movement path of the slit coating head. The adsorption ends of the two solvent recovery auxiliary units face the coating area inside the locally sealed cavity.

[0011] Preferably, the operation of the solvent recovery auxiliary unit is linked to the humidity control. When the solvent concentration sensor detects that the concentration of a specific solvent exceeds a preset threshold, the controller dynamically increases the pumping speed of the vacuum pump and starts the regeneration program of the adsorbent material for that solvent. The system control module also includes a solvent recovery linkage submodule, which can receive solvent concentration detection data in the locally sealed cavity. When the concentration is greater than a preset maximum value, the pumping speed of the micro vacuum pump is increased, and when the concentration is less than a preset minimum value, the pumping speed is reduced.

[0012] Preferably, the system control module further includes a dynamic power adjustment submodule, which can adjust the operating power of the micro dehumidifier and micro humidifier according to a preset gradient based on the compensation amount output by the humidity deviation compensation algorithm module.

[0013] Preferably, the system control module further includes a fault diagnosis submodule and an airflow uniform distribution coordination submodule. The fault diagnosis submodule can monitor the current and voltage data of the precision humidity adjustment module and the solvent recovery auxiliary unit in real time. When the current of the micro dehumidification unit is greater than 150% of the rated value or the voltage of the micro vacuum pump is less than 85% of the rated value, a fault alarm signal is triggered and a fault code is recorded.

[0014] Preferably, the airflow uniform distribution coordination submodule can adjust the airflow distribution of the airflow distribution device according to the output of the humidity deviation compensation algorithm module. For areas where the humidity deviation is greater than the minimum deviation value, the airflow of the corresponding airflow nozzle is increased, and the flow rate is adjusted through the built-in airflow distribution valve.

[0015] This invention provides a separate moisture control device for slot coating. It has the following beneficial effects: 1. This invention, through a locally sealed cavity design, controls humidity only in key coating areas. Compared to overall environmental humidity control solutions, this reduces energy consumption, significantly lowers operating costs, and improves industrial economics. It is also highly adaptable to large-size coating and has strong scalability: the locally sealed cavity can be flexibly adapted to industrial-grade large-size coating heads, overcoming the limitations of traditional glove boxes with fixed volumes that can only be used for small-scale coatings, and solving the problem of poor adaptability to large-size coating equipment.

[0016] 2. This invention employs a real-time feedback control module and a precise humidity adjustment module, combined with a predictive control algorithm based on a humidity-solvent evaporation coupling model, to achieve more precise humidity control, shorten response time, effectively offset local humidity fluctuations caused by solvent evaporation, and ensure coating uniformity. Airflow-free coating improves film quality: Through the airflow distribution plate design, the humidity-controlled airflow uniformly covers the coating surface at a low speed, avoiding high-speed airflow disturbance to the uncured coating, reducing streaks and sagging defects, and significantly improving device performance.

[0017] 3. This invention integrates a solvent recovery auxiliary unit, which improves solvent recovery efficiency, avoids abnormal humidity and sensor corrosion caused by solvent accumulation, extends sensor life, and reduces maintenance costs and equipment wear.

[0018] 4. The system control module of this invention incorporates a humidity deviation compensation algorithm and a dynamic power adjustment submodule. It can predict humidity change trends based on real-time data and adjust the power of the dehumidifier or humidifier unit in advance, achieving rapid closed-loop control and improving production efficiency and process stability. The system control module also integrates a fault diagnosis submodule, which monitors the current and voltage of key components in real time. In case of abnormalities, it triggers alarms and records fault codes. Simultaneously, the sensor calibration submodule automatically calibrates periodically to ensure data accuracy and reduce manual intervention and maintenance time. Attached Figure Description

[0019] Figure 1 This is a diagram of the architecture of the present invention.

[0020] The components include: 1. Coating head; 2. Humidity sensor; 3. Base; 4. Substrate; 5. Micro mechanical pump; 6. Airflow distribution device; 7. Local sealing cavity; 8. Airflow distribution plate; and 9. Controller. Detailed Implementation

[0021] The technical solution of the present invention will now be clearly and completely described 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.

[0022] Please see the appendix Figure 1This invention provides a separate humidity control device for slot coating, comprising a base 3, a locally sealed cavity 7, a precise humidity control module, a real-time feedback module, a solvent recovery auxiliary unit, a system control module, and an airflow distribution device 6. The base 3 supports and fixes the slot coating head 1 and the locally sealed cavity 7. The locally sealed cavity 7 is arranged around the outlet of the slot coating head 1 and the coating transmission path, and is fixed on the base 3. The precise humidity control module, the real-time feedback module, and the solvent recovery auxiliary unit are all integrated on the locally sealed cavity 7 or the base 3. The airflow distribution device 6 is disposed inside the locally sealed cavity 7 for guiding and evenly distributing the humidity-controlled airflow. The system control module is electrically connected to the precise humidity control module, the real-time feedback module, and the solvent recovery auxiliary unit, respectively. The system control module has a built-in humidity deviation compensation algorithm module, pre-stores the humidity interference coefficients corresponding to different precursor solvents, and can receive humidity detection data transmitted by the real-time feedback module, calculate the humidity compensation amount, and send it to the precise humidity control module.

[0023] Specifically, the device of this invention includes a base 3, a locally sealed cavity 7, a precise humidity control module, a real-time feedback module, a solvent recovery auxiliary unit, a system control module, and an airflow distribution device 6. These components work together to achieve precise humidity control and stable operation of the local environment. The base 3 is equipped with positioning guide rails and fixing holes. A bolt assembly ensures the coaxial positioning and stable fixation of the slit coating head 1 and the locally sealed cavity 7, guaranteeing a stable relative position between the coating head 1 outlet and the sealed cavity. The locally sealed cavity 7 is arranged around the coating head 1 outlet and the coating transfer path, fixed to a pre-set mounting surface of the base 3, and is made of transparent polycarbonate with a volume of only 0.05-0.2 m³. 3This significantly reduces humidity control energy consumption. The connection surface between the chamber and the base features a sealing groove and an internal fluororubber gasket, effectively isolating external interference. The precision humidity control module integrates a micro dehumidification unit and a humidification unit. Its modular design and quick-release structure allow for integration into the chamber sidewall or base mounting. The micro dehumidification unit uses a small molecular sieve dehumidification core, while the micro humidification unit employs ultrasonic atomization technology for rapid humidity adjustment. The real-time feedback module consists of a high-precision capacitive humidity sensor 2 and a signal processing unit, collecting humidity data from the coating area in real time and transmitting it to the system control module. The solvent recovery auxiliary unit includes a power and adsorption component, fixed to the top or side of the chamber or integrated into the reserved space on the base. Designed to address precursor solvent evaporation, it recovers evaporating solvent in real time, preventing localized humidification and equipment corrosion. The airflow distribution device 6 is located on the outlet side of the precision humidity control module inside the chamber, including an arc-shaped guide plate and a uniformly distributed perforated plate with a pore size of 1-3 μm, avoiding disturbance to the uncured coating and ensuring uniform humidity. The system control module, centered on a PLC and installed in the base electrical control cabinet, connects to various modules via cables. It features signal acquisition, data processing, and command output functions. Its built-in humidity deviation compensation algorithm module pre-stores humidity interference coefficients for different precursor solvents. Through an experimentally established database of solvent types, evaporation rates, and humidity deviations, it calculates compensation amounts in real-time, combining detection data with corresponding interference coefficients, and dynamically adjusts dehumidification or humidification power to counteract solvent evaporation interference. This application sets the target humidity and selects the solvent type based on the film material, and the system calls the corresponding interference coefficient. After startup, the precise humidity adjustment module quickly adjusts the cavity humidity to approach the target value, and the airflow distribution device guides uniform airflow. Coating head 1 initiates coating, substrate 4 moves at a constant speed, the real-time feedback module collects humidity data, and the solvent recovery unit simultaneously recovers evaporating solvents. The system control module calculates the deviation and compensation amount through the humidity deviation compensation algorithm, and the closed-loop control adjustment module dynamically adjusts the humidity back to ensure stable humidity in key coating areas, providing a stable local environment for the preparation of high-precision functional films.

[0024] The real-time feedback module is configured to execute a predictive control algorithm based on a humidity-solvent evaporation coupling model. By collecting data on the coating speed, precursor solution evaporation rate, and airflow velocity within the cavity in real time, it predicts future humidity trends and adjusts the power of the dehumidification or humidification unit in advance to counteract the main interference of solvent evaporation on humidity. The real-time feedback module includes two humidity sensors 2, a controller 9, and a solvent concentration sensor. The two humidity sensors 2 are respectively located on both sides of the coating transmission path and are both electrically connected to the controller 9. The controller 9 is electrically connected to the micro dehumidification unit and the micro humidification unit, respectively.

[0025] Specifically, the predictive control algorithm is based on a humidity-solvent evaporation coupling model established through extensive experimental data. Its core lies in revealing the quantitative relationship between humidity changes and solvent evaporation rates, coating speed, and airflow velocity within the cavity during the coating process. The model expression is ΔRH=k1×v_coat+k2×v_vol+k3×v_air+ε, where ΔRH is the humidity change (%RH), v_coat is the coating speed (0.5-5 m / min), v_vol is the experimentally calibrated precursor solution evaporation rate (mL / min), and v_a... ir is the airflow velocity (m / s) inside the cavity, k1, k2, and k3 are the fitting coefficients obtained through multiple linear regression, and ε is the error term. The algorithm execution process includes data acquisition, collecting three sets of data per second of coating speed, solvent evaporation rate, and airflow velocity through sensors, trend prediction, inputting the data into the model to calculate the humidity change trend in the next 5-10 seconds, predicting whether it exceeds the target range, and adjusting in advance. Based on the prediction results, a power adjustment command is sent to the precision humidity adjustment module in advance to shorten the humidity adjustment response lag time and effectively suppress local humidity fluctuations caused by solvent evaporation. The real-time feedback module consists of two high-precision capacitive humidity sensors 2, installed at the front and rear ends of the locally sealed cavity, respectively, to comprehensively detect the humidity distribution in the coating area. When the difference between the two sensor data exceeds 1%RH, an airflow uniformity adjustment program is initiated. The controller 9 connects to the humidity sensors 2 via an I2C interface and to the solvent concentration sensor via an RS485 interface. It also utilizes a PWM output module to connect to the drive circuit of the miniature dehumidification or humidification unit, enabling continuous power adjustment. The solvent concentration sensor, designed for solvents such as DMF and DMSO, is installed at the top of the cavity near the concentrated solvent evaporation area, providing data for the prediction algorithm and linking with the solvent recovery auxiliary unit. After coating begins, the two humidity sensors 2 and the solvent concentration sensor collect data in real time. After preliminary processing, the controller 9 inputs the coating speed, solvent evaporation rate, and airflow speed into the coupled model for predictive control. If the predicted humidity exceeds the target range, the controller 9 immediately adjusts the power of the miniature dehumidification or humidification unit via a PWM signal to preemptively offset humidity changes. Simultaneously, the controller 9 compares the data from the two humidity sensors 2 in real time, and when the difference exceeds 1%RH, it links with the airflow distribution device to adjust the local airflow, ensuring uniform humidity within the cavity.

[0026] The real-time feedback module also includes a micro-pressure monitoring unit inside the cavity. The controller 9 maintains a slight positive pressure inside the cavity to prevent external ambient air from infiltrating, and uses air pressure as an auxiliary variable to participate in the closed-loop feedback of humidity control. The data filtering submodule of the controller 9 uses a moving average filtering algorithm to process the real-time humidity data collected by the two humidity sensors 2, filtering out instantaneous interference signals with a frequency less than the minimum value, and the size of the filtering window can be set by the system control module.

[0027] Specifically, the micro-pressure monitoring unit within the cavity includes a miniature pressure sensor and a pressure regulating actuator. The miniature pressure sensor is installed on the inner side wall of the partially sealed cavity near the top to detect the pressure value in real time. The pressure regulating actuator is a small electromagnetic proportional valve installed on the cavity's air inlet pipe. Both are electrically connected to the controller 9 via signal lines. During operation, the miniature pressure sensor transmits a pressure detection value to the controller 9, which compares it with a target value: when the detected pressure is below 1.02 atm, the controller increases the air intake to raise the pressure; when the detected pressure is above 1.05 atm, the controller decreases the air intake or opens the small electromagnetic pressure relief valve at the top of the cavity to release gas, causing the pressure to drop back to the target range. Simultaneously, the pressure data serves as an auxiliary variable in the humidity control closed-loop feedback. The data filtering submodule is integrated into the controller 9 software system. It employs a moving average filtering algorithm to process real-time humidity data collected every 100ms from the two humidity sensors 2. By selecting an adjustable filtering window, it performs an arithmetic average of the continuous data within the window, using the average value as the effective output, thereby filtering out instantaneous interference signals. For processes with small humidity fluctuations, a larger window is set to enhance the filtering effect; for processes with high humidity response requirements, a smaller window is set to balance the filtering effect and response speed. A micro-pressure sensor detects air pressure in real time. The controller 9 adjusts the actuator to maintain a slight positive pressure and uses the air pressure data to assist in humidity decision-making. After processing by the humidity sensor 2 filtering submodule, the effective humidity value is output. The controller 9 then combines the effective humidity, air pressure, and solvent concentration data, and calculates the humidity adjustment amount using a predictive control algorithm based on the humidity-solvent evaporation coupling model. It then sends a power adjustment command to the humidity adjustment module, ultimately achieving precise and stable humidity control.

[0028] The partial sealing cavity 7 is made of transparent polycarbonate. Both ends of the partial sealing cavity 7 are provided with openings adapted to the coating transmission path. Flexible sealing gaskets are provided at the openings and are attached to the surface of the substrate 4. The precision humidity control module includes a micro dehumidification unit, a micro humidification unit and an airflow distribution plate 8. The micro dehumidification unit and the micro humidification unit are arranged side by side. The airflow distribution plate 8 is located on the side wall of the partial sealing cavity 7 and covers the air outlet side of the micro dehumidification unit and the micro humidification unit.

[0029] Specifically, the local sealing cavity 7 is injection molded from transparent polycarbonate (PC) sheet, forming a rectangular frame structure that balances adaptability to large-size coatings with low-energy humidity control requirements. Openings are located at both ends of the cavity, slightly wider than the substrate 4 and slightly taller than the substrate thickness, ensuring smooth passage of the substrate. Flexible silicone rubber gaskets are installed at the openings and secured using a slot structure, achieving a leakage rate of less than 0.1m. 3The system provides a high-quality seal while preventing resistance to substrate transmission or surface scratches. Four symmetrical mounting feet, equipped with rubber shock-absorbing pads and spring washers, are fixed to the base 3 at the bottom of the chamber. The precision humidity control module includes a miniature dehumidifier unit, a miniature humidifier unit, and an airflow distribution plate 8, integrated within the same mounting frame. It is installed at the mounting port on the side wall of the chamber using quick-release bolts, and a sealing gasket ensures a reliable seal. The miniature dehumidifier unit uses a miniaturized rotary molecular sieve dehumidifier, with its inlet connected to an external dry air source. The miniature humidifier unit uses an ultrasonic atomizing humidifier, installed alongside the dehumidifier unit, with their outlets both facing the airflow distribution plate 8. The airflow distribution plate 8, fixed to the inside of the mounting port on the side wall of the chamber, is made of porous ceramic material and features an array of through-holes to ensure uniform airflow diffusion. During operation, the corresponding units are activated according to system instructions: when the humidity is higher than the target value, the dehumidification unit generates low-humidity airflow; when the humidity is lower than the target value, the humidification unit generates humidifying airflow; the airflow distribution plate 8 ensures that the airflow is uniformly diffused into the cavity at a low speed of less than 0.5 m / s, covering the entire coating transmission path and ensuring minimal humidity deviation. The locally sealed cavity effectively isolates the external environment through a flexible sealing gasket, and together with the uniform airflow output of the precision humidity adjustment module, achieves precise and stable control of local humidity.

[0030] The airflow distribution plate 8 is made of porous ceramic material, and its area is adapted to the inner wall area of ​​the local sealing cavity 7. The air outlet direction of the airflow distribution plate 8 is set at an angle of 30-60° with the coating transmission direction. The airflow distribution device 6 includes multiple sets of independently adjustable airflow nozzles. The outlet angle and flow rate of each set of nozzles can be adjusted by the system control module to fine-tune the humidity at different locations in the coating area. The airflow coverage width is consistent with the coating width.

[0031] Specifically, the airflow distribution plate 8 is made of porous ceramic material, and its through-hole parameters are designed according to the coating width. The air outlet direction forms a 30–60° angle with the coating transmission direction, which can fully contact the coating, avoid airflow disturbance, and facilitate the guidance of volatile solvents to the recovery unit. The airflow distribution device 6 is installed on the top of the local sealed cavity 7, extending along the width direction, with a length consistent with the coating width and a width of 0.2–0.3m. The installation height is finely adjustable. It includes multiple sets of independently adjustable fan-shaped nozzles. Each set of nozzles can rotate around its axis and is equipped with a miniature electromagnetic proportional valve. The flow rate is continuously adjusted by the PWM signal output by the system control module, thereby achieving independent control of angle and flow rate, ensuring coverage without blind spots and precise compensation for local humidity deviations. The airflow distribution plate 8 achieves basic humidity uniformity with oblique airflow; the system control module, based on real-time humidity feedback, performs local fine-tuning by adjusting its outlet angle and increasing the flow rate, so that the humidity quickly returns to the target range.

[0032] The solvent recovery auxiliary unit includes a micro vacuum pump 5 and an activated carbon adsorption device. The micro vacuum pump 5 and the activated carbon adsorption device are connected by a pipeline. The micro vacuum pump 5 is set on both sides of the local sealed cavity 7. There are two solvent recovery auxiliary units, which are symmetrically set on both sides of the movement path of the slit coating head 1. The adsorption ends of the two solvent recovery auxiliary units are facing the coating area inside the local sealed cavity 7.

[0033] Specifically, the solvent recovery auxiliary unit includes a micro vacuum pump 5 and an activated carbon adsorption device, which are connected by a corrosion-resistant PTFE pipe to form a closed recovery loop. The inlet of the micro vacuum pump 5 extends through a pipe into the interior of the partially sealed cavity 7, while the outlet is connected to the inlet of the activated carbon adsorption device. The activated carbon adsorption device is filled with high specific surface area activated carbon. The outlet of the adsorption tank is equipped with an exhaust pipe and a secondary activated carbon filter at the end. The tank is also equipped with a pressure monitoring interface to facilitate real-time monitoring of the internal pressure and determination of the adsorption saturation state. In terms of installation layout, two solvent recovery auxiliary units are symmetrically arranged on both sides of the movement path of the slit coating head 1 and fixed to the outer wall of the local sealing cavity 7, with flange sealing connection to prevent leakage. The adsorption ends of both units face the coating area inside the cavity. The air inlet is equipped with a trumpet-shaped suction nozzle, the opening direction of which is at a 45° angle with the coating transmission direction, and the vertical distance from the coating surface is 8–12 cm. The inlet of the suction nozzle is also equipped with a protective mesh with a 0.5 mm aperture to prevent impurities from being sucked in. This symmetrical layout forms an adsorption airflow field covering the critical area from the outlet of the coating head 1 to the coating curing stage, which can efficiently capture volatile solvent vapors. The solvent recovery auxiliary units start synchronously with the coating operation: after the micro vacuum pump 5 runs, it forms a negative pressure adsorption field in the local sealing cavity 7, sucking the volatile solvent vapors into the suction nozzle, which is then transported through the pipeline to the vacuum pump and pressed into the activated carbon adsorption device. In the tank, the solvent molecules are adsorbed and trapped by the activated carbon, and the purified gas is discharged through the exhaust pipe. When the activated carbon is saturated, the vacuum pump is turned off and the activated carbon is replaced or the regeneration program is started. This symmetrical adsorption layout can effectively capture solvent vapor at different locations in the coating area, reducing the corrosion of the humidity sensor 2 by the solvent.

[0034] The operation of the solvent recovery auxiliary unit is linked with the humidity control. When the solvent concentration sensor detects that the concentration of a specific solvent exceeds the preset threshold, the controller 9 dynamically increases the pumping speed of the vacuum pump and starts the regeneration program of the adsorbent material for that solvent. The system control module also includes a solvent recovery linkage submodule, which can receive solvent concentration detection data in the local sealed cavity 7. When the concentration is greater than the preset maximum value, the pumping speed of the micro vacuum pump 5 is increased, and when the concentration is less than the preset minimum value, the pumping speed is reduced.

[0035] Specifically, the system uses a semiconductor gas sensor to detect the solvent concentration in the locally sealed cavity 7 in real time and transmits the data to the solvent recovery linkage submodule of the system control module. This submodule dynamically controls the pumping speed of the micro vacuum pump 5 according to a preset solvent concentration threshold: when the concentration exceeds the preset maximum value, the pumping speed increases to 1.2–1.5 times the baseline value; when the concentration is below the preset minimum value, the pumping speed decreases to 0.6–0.8 times the baseline value; within the threshold range, the baseline pumping speed is maintained, thereby achieving a balance between recovery efficiency and energy consumption. Simultaneously, the system has a built-in adsorbent material regeneration program, setting regeneration parameters for different solvents. When a specific solvent concentration is detected to be continuously exceeding the limit or when manually triggered by the user, the system automatically starts the regeneration process: stopping the vacuum pump 5, closing the inlet valve, heating the adsorption tank to the set temperature and purging with nitrogen gas, guiding the purged solvent into the recovery tank, cooling after regeneration, and resuming operation. This achieves dynamic adjustment of solvent recovery intensity and precise regeneration of the adsorbent material, balancing recovery efficiency, energy consumption reduction, and long-term operational stability.

[0036] The system control module also includes a dynamic power adjustment submodule, which can adjust the operating power of the micro dehumidifier and micro humidifier according to the compensation amount output by the humidity deviation compensation algorithm module and a preset gradient.

[0037] Specifically, the dynamic power adjustment submodule is integrated into the system control module's software system. Its core function is to adjust the operating power of the micro dehumidifier and micro humidifier according to preset gradients based on the humidity compensation amount output by the humidity deviation compensation algorithm module. The power adjustment range of the micro dehumidifier is 0–100% of its rated power, divided into 10 gradients, each corresponding to a 10% power increment. For example, gradient 1 is 10W, gradient 2 is 20W, and so on up to gradient 10, which is 100W. The rated power of the micro humidifier is 60W, also divided into 10 gradients, each incrementing by 10%, such as gradient 1 being 6W, gradient 2 being 12W, and so on up to gradient 10, which is 60W. Through experimental testing, the correspondence between humidity compensation and power gradient was established and stored in this submodule. For example, when the humidity compensation (ΔRH) is 0–0.5%RH, both the dehumidification and humidification units correspond to gradient 1; when the compensation is 0.5–1.0%RH, it corresponds to gradient 2–3; 1.0–1.5%RH corresponds to gradient 4–5; 1.5–2.0%RH corresponds to gradient 6–7; and above 2.0%RH, it corresponds to gradient 8–10. The larger the compensation, the higher the corresponding power gradient, and the stronger the adjustment. The specific gradient selection can also be dynamically adjusted according to the actual rate of humidity change. For example, when the humidity rises rapidly, a higher gradient within the same compensation range can be selected.

[0038] The system control module also includes a fault diagnosis submodule and an airflow distribution coordination submodule. The fault diagnosis submodule can monitor the current and voltage data of the precision humidity adjustment module and the solvent recovery auxiliary unit in real time. When the current of the micro dehumidification unit is greater than 150% of the rated value or the voltage of the micro vacuum pump 5 is less than 85% of the rated value, a fault alarm signal is triggered and the fault code is recorded.

[0039] Specifically, the fault diagnosis submodule of this invention achieves fault diagnosis by real-time monitoring of electrical parameters: current sensors are connected in series in the power supply circuits of the micro dehumidifier, micro humidifier, and micro vacuum pump 5, and voltage sensors are connected in parallel at the power input terminal. These sensors are all connected to the system control module via I2C interfaces; a fault judgment threshold is set. The airflow uniformity coordination submodule performs coordinated control based on the real-time output of the humidity deviation compensation algorithm module: after receiving the command, it determines the deviation area and deviation value, and adjusts the air output of the corresponding nozzle group of the airflow distribution device 6. For positive deviation areas, it accelerates airflow circulation to remove moisture, and for negative deviation areas, it increases the supply of humidifying airflow. At the same time, it links with the precision humidity adjustment module to fine-tune the overall power of the dehumidifier or humidifier unit, quickly correcting the humidity deviation. The fault diagnosis submodule continuously monitors electrical parameters, promptly alarms and handles faults, while the airflow uniformity coordination submodule adjusts airflow and power in real time to collaboratively eliminate local humidity deviations. This achieves real-time diagnosis and protection of equipment faults, avoids production losses, and improves humidity regulation efficiency through coordinated control, ensuring the consistency of coating quality.

[0040] The airflow uniformity coordination submodule can adjust the airflow distribution of the airflow distribution device 6 according to the output of the humidity deviation compensation algorithm module. For areas with humidity deviation greater than ±1.5%RH, it can increase the airflow of the corresponding airflow nozzles and achieve flow regulation through the built-in airflow distribution valve.

[0041] Specifically, this invention achieves precise matching between airflow rate and humidity deviation by optimizing the control logic of the airflow uniform distribution coordination submodule and the airflow distribution valve. The airflow uniform distribution coordination submodule incorporates a humidity deviation-airflow rate adjustment curve fitted from a large amount of experimental data, with the mathematical expression Q=k×ΔRH+Q0, where Q is the target airflow rate (L / min), ΔRH is the absolute value of the humidity deviation (%RH), k is the flow rate adjustment coefficient, and Q0 is the reference airflow rate. In the control logic, the humidity deviation compensation algorithm module calculates the humidity deviation value at different locations in the coating area in real time and sends the deviation value and corresponding nozzle group information to the airflow uniform distribution coordination submodule. The submodule calculates the target airflow rate Q according to the formula, then detects the current actual flow rate through a flow sensor, calculates the adjustment amount, and sends a signal to the airflow distribution valve to adjust the outlet airflow of the corresponding nozzle group to the target value. The airflow distribution valve adopts a miniature electromagnetic proportional valve, with one valve corresponding to each nozzle group. The valve opening is controlled by a PWM signal, and the duty cycle of 0-100% is linearly related to the opening. By combining the control logic with the high-precision airflow distribution valve, the adjustment efficiency and accuracy of local humidity deviation are improved, ensuring uniform humidity in the coating area and meeting the requirements for high-precision functional film preparation.

[0042] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A separate moisture control device for slot coating, characterized in that: The system includes a base (3), a partially sealed cavity (7), a precision humidity control module, a real-time feedback module, a solvent recovery auxiliary unit, a system control module, and an airflow distribution device (6). The base (3) supports and fixes the slit coating head (1) and the partially sealed cavity (7). The partially sealed cavity (7) is arranged around the outlet of the slit coating head (1) and the coating transmission path, and is fixed on the base (3). The precision humidity control module, the real-time feedback module, and the solvent recovery auxiliary unit are all integrated on the partially sealed cavity (7) or the base (3). The airflow distribution device (6) is set inside the partially sealed cavity (7) to guide and evenly distribute the controlled humidity airflow. The system control module is electrically connected to the precision humidity control module, the real-time feedback module, and the solvent recovery auxiliary unit, respectively. The system control module has a built-in humidity deviation compensation algorithm module, which pre-stores the humidity interference coefficients corresponding to different precursor solvents, and can receive the humidity detection data transmitted by the real-time feedback module, calculate the humidity compensation amount, and send it to the precision humidity control module.

2. The slit coating individual humidity control device according to claim 1, characterized in that, The real-time feedback module is configured to execute a predictive control algorithm based on a humidity-solvent evaporation coupling model. By collecting the coating speed, precursor solution evaporation rate and airflow speed in the cavity in real time, it predicts the future humidity change trend and adjusts the power of the dehumidification or humidification unit in advance to counteract the main interference of solvent evaporation on humidity. The real-time feedback module includes two humidity sensors (2), a controller (9) and a solvent concentration sensor. The two humidity sensors (2) are respectively set on both sides of the coating transmission path and are electrically connected to the controller (9). The controller (9) is electrically connected to the micro dehumidification unit and the micro humidification unit respectively.

3. The slit coating individual humidity control device according to claim 2, characterized in that, The real-time feedback module also includes a micro-pressure monitoring unit inside the cavity. The controller (9) prevents external ambient air from infiltrating by maintaining a micro-positive pressure inside the cavity and uses air pressure as an auxiliary variable to participate in the closed-loop feedback of humidity control. The data filtering submodule of the controller (9) uses a moving average filtering algorithm to process the real-time humidity data collected by the two humidity sensors (2), filter out instantaneous interference signals with a frequency less than the minimum value, and the size of the filtering window can be set by the system control module.

4. The slot coating separate humidity control device according to claim 1, characterized in that, The material of the local sealing cavity (7) is transparent polycarbonate. The two ends of the local sealing cavity (7) are provided with openings adapted to the coating transmission path. A flexible sealing gasket is provided at the opening. The flexible sealing gasket is attached to the surface of the substrate (4). The precise humidity adjustment module includes a micro dehumidification unit, a micro humidification unit and an airflow distribution plate (8). The micro dehumidification unit and the micro humidification unit are arranged side by side. The airflow distribution plate (8) is arranged on the side wall of the local sealing cavity (7) and covers the air outlet side of the micro dehumidification unit and the micro humidification unit.

5. The slot coating individual humidity control device according to claim 4, characterized in that, The airflow distribution plate (8) is made of porous ceramic material, and its area is adapted to the inner wall area of ​​the local sealing cavity (7). The air outlet direction of the airflow distribution plate (8) is set at an angle of 30-60° with the coating transmission direction. The airflow distribution device (6) includes multiple sets of independently adjustable airflow nozzles. The outlet angle and flow rate of each set of nozzles can be adjusted by the system control module to fine-tune the humidity at different positions in the coating area. The airflow coverage width is consistent with the coating width.

6. The slot coating separate humidity control device according to claim 1, characterized in that, The solvent recovery auxiliary unit includes a micro vacuum pump (5) and an activated carbon adsorption device. The micro vacuum pump (5) and the activated carbon adsorption device are connected by a pipeline. The micro vacuum pump (5) is set on both sides of the local sealed cavity (7). There are two solvent recovery auxiliary units, which are symmetrically set on both sides of the movement path of the slit coating head (1). The adsorption ends of the two solvent recovery auxiliary units are facing the coating area inside the local sealed cavity (7).

7. A slit coating individual humidity control device according to claim 6, characterized in that, The operation of the solvent recovery auxiliary unit is linked with the humidity control. When the solvent concentration sensor detects that the concentration of a specific solvent exceeds the preset threshold, the controller (9) dynamically increases the pumping speed of the vacuum pump and starts the adsorption material regeneration program for the solvent. The system control module also includes a solvent recovery linkage sub-module. The solvent recovery linkage sub-module can receive the solvent concentration detection data in the local sealed cavity (7). When the concentration is greater than the preset maximum value, the pumping speed of the micro vacuum pump (5) is increased, and when the concentration is less than the preset minimum value, the pumping speed is reduced.

8. The slot coating separate humidity control device according to claim 1, characterized in that, The system control module also includes a dynamic power adjustment submodule, which can adjust the operating power of the micro dehumidifier and micro humidifier according to a preset gradient based on the compensation amount output by the humidity deviation compensation algorithm module.

9. A slit coating individual humidity control device according to claim 1, characterized in that, The system control module also includes a fault diagnosis submodule and an airflow distribution coordination submodule. The fault diagnosis submodule can monitor the current and voltage data of the precision humidity adjustment module and the solvent recovery auxiliary unit in real time. When the current of the micro dehumidification unit is greater than 150% of the rated value or the voltage of the micro vacuum pump (5) is less than 85% of the rated value, a fault alarm signal is triggered and the fault code is recorded.

10. A slit coating individual humidity control device according to claim 9, characterized in that, The airflow uniform distribution coordination submodule can adjust the airflow distribution of the airflow distribution device (6) according to the output of the humidity deviation compensation algorithm module. For areas where the humidity deviation is greater than the minimum deviation value, it can increase the airflow of the corresponding airflow nozzles and achieve flow regulation through the built-in airflow distribution valve.

Images