High-precision film formation consistency control method for OLED inkjet printed films

Abstract

The present application discloses a method for controlling the consistency of high-precision film formation of an OLED inkjet-printed film, and relates to the technical field of inkjet printing, including: In the present application, a method for controlling the consistency of high-precision film formation of an OLED inkjet-printed film is proposed, which is particularly suitable for consistent film formation in the manufacture of large-area displays. First, a wet film uniformly formed on the substrate is obtained based on the surface morphology data of a single sub-pixel of the substrate and the ink atomization characteristic parameters; then, by combining the simulation analysis of the macroscopic cavity physical field and the simulation analysis of the wet film curing in the microscopic sub-pixel groove, the process parameters for consistent curing film formation are determined, and the wet film uniformly formed on the substrate is dried and cured according to the process parameters to obtain a target dry film. In this way, with reference to the process parameters obtained by analyzing the macroscopic cavity physical field and the wet film curing in the microscopic sub-pixel groove, the uniformly formed wet film is dried and cured to obtain a target dry film with consistent film thickness and uniform film formation.

Description

Technical Field

[0001] The present application relates to the technical field of inkjet printing, and in particular to a method for controlling the high-precision film formation consistency of an OLED inkjet printed film. Background Art

[0002] OLED (Organic Light Emitting Diode) display technology is widely used in the manufacture of various high-end displays due to its advantages such as self-luminescence, high contrast and wide viewing angle. In the manufacture of OLED displays, inkjet printing technology has gradually become a mainstream manufacturing process, especially in the production of large-area displays. Compared with the traditional mask evaporation process, inkjet printing has the advantages of low equipment cost, high material utilization rate and strong flexibility. However, in the inkjet printing process, the temperature control of the film forming process and the uniformity of the film thickness have always been the key factors affecting the quality of the final product.

[0003] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0004] The main purpose of the present application is to provide a method for controlling the high-precision film formation consistency of an OLED inkjet-printed film, aiming to solve the technical problem of inconsistent film thickness on a large-area substrate.

[0005] To achieve the above-mentioned purpose, the present application proposes a method for controlling the high-precision film formation consistency of an OLED inkjet printed film, the method comprising:

[0006] Obtaining and obtaining a uniformly formed wet film on the substrate based on the single sub-pixel surface morphology data of the substrate and the ink atomization characteristic parameters;

[0007] By combining the macroscopic cavity physical field simulation analysis with the microscopic sub-pixel groove wet film curing simulation analysis, the process parameters for consistent curing film formation are determined;

[0008] Referring to the process parameters, the wet film uniformly formed on the substrate is dried and solidified to obtain a target dry film.

[0009] In one embodiment, the step of obtaining a uniformly formed wet film on the substrate based on the single sub-pixel surface morphology data of the substrate and the ink atomization characteristic parameters comprises:

[0010] According to the surface morphology data of a single sub-pixel on the substrate and the ink atomization characteristic parameters, the maximum volume that can be accommodated by the ink droplet in the single sub-pixel slot and the maximum inkjet offset distance are obtained through simulation analysis;

[0011] According to the maximum accommodating volume of ink droplets in a single sub-pixel slot and the maximum inkjet offset distance, ink printing planning is performed to obtain a uniformly formed wet film on the substrate.

[0012] In one embodiment, in the macroscopic cavity physical field simulation analysis, a uniformly distributed temperature field and airflow field are obtained through simulation calculation and optimization iteration according to initial process parameters.

[0013] In one embodiment, in the simulation analysis of wet film curing in the microscopic sub-pixel groove, the dry film morphology after drying and curing is obtained through simulation calculation based on the uniformly distributed temperature field and airflow field and the latest wet film morphology.

[0014] In one embodiment, the step of determining the process parameters for uniform film curing by combining macroscopic cavity physical field simulation analysis and microscopic sub-pixel groove wet film curing simulation analysis includes:

[0015] When the dry film morphology obtained by simulation calculation is inconsistent with the target dry film morphology of consistent curing film under ideal conditions, the initial process parameters are optimized until the dry film morphology obtained by simulation calculation is consistent with the target theoretical dry film morphology, thereby obtaining the process parameters of consistent curing film.

[0016] In one embodiment, the step of drying and curing the wet film uniformly formed on the substrate with reference to the process parameters to obtain a target dry film comprises:

[0017] The temperature of the process parameter is used as the set temperature, and the target control temperature for temperature control of the water cooling system and the electric heating system is determined by PID control;

[0018] Based on the target control temperature, controlling the coolant flow rate of the water cooling system;

[0019] Based on the target control temperature, power control is performed on the electric heating system.

[0020] In one embodiment, the step of controlling the coolant flow rate of the water cooling system based on the target control temperature includes:

[0021] Obtain the coolant inlet temperature, the amount of heat to be removed during cooling, and the specific heat capacity of the coolant;

[0022] Determining a cooling change temperature according to the target control temperature and the inlet temperature of the coolant;

[0023] determining a target flow rate of the coolant according to the cooling change temperature, the amount of heat to be removed during the cooling process, and the specific heat capacity of the coolant;

[0024] The real-time flow rate of the coolant in the water cooling system is controlled at the target flow rate.

[0025] In one embodiment, the step of performing power control on the electric heating system based on the target control temperature includes:

[0026] Obtain the real-time temperature of the electric heating element in the electric heating system;

[0027] According to the real-time temperature and the target control temperature, the power of the electric heating element in the electric heating system is determined through PID control.

[0028] In one embodiment, the method further comprises:

[0029] Obtaining the boiling point of the ink solvent of each single sub-pixel of the substrate;

[0030] The power distribution of the electric heating element is adjusted according to the boiling point of the ink solvent of each single sub-pixel on the substrate.

[0031] In one embodiment, the method further comprises:

[0032] A gradient distribution strategy is adopted to arrange the electric heating elements in the edge area of ​​the substrate; wherein the arrangement density of the electric heating elements in the edge area of ​​the substrate is greater than that in the non-edge area of ​​the substrate.

[0033] In addition, to achieve the above-mentioned purpose, the present application also proposes a high-precision film formation consistency control device for an OLED inkjet printed film, the high-precision film formation consistency control device for an OLED inkjet printed film comprising:

[0034] A wet film module is used to obtain and obtain a uniformly formed wet film on the substrate based on the single-pixel surface morphology data of the substrate and the ink atomization characteristic parameters;

[0035] A simulation module is used to determine the process parameters for consistent film curing by combining macroscopic cavity physical field simulation analysis and microscopic sub-pixel groove wet film curing simulation analysis;

[0036] The dry film module is used to dry and solidify the wet film uniformly formed on the substrate with reference to the process parameters to obtain a target dry film.

[0037] In addition, to achieve the above-mentioned purpose, the present application also proposes an inkjet printing device, which includes: a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the computer program is configured to implement the steps of the method for controlling high-precision film formation consistency of OLED inkjet printed films as described above.

[0038] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by the processor, the steps of the high-precision film formation consistency control method of the OLED inkjet printing film as described above are implemented.

[0039] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, it implements the steps of the high-precision film formation consistency control method of the OLED inkjet printing film as described above.

[0040] One or more technical solutions proposed in this application have at least the following technical effects:

[0041] In the present application, a method for controlling the high-precision film formation consistency of an OLED inkjet-printed film is proposed, which is particularly suitable for consistent thin film formation in the manufacture of large-area displays. First, a wet film uniformly formed on the substrate is obtained based on the surface morphology data of a single sub-pixel of the substrate and the ink atomization characteristic parameters; then, by combining the macroscopic cavity physical field simulation analysis and the wet film curing simulation analysis in the microscopic sub-pixel groove, the process parameters for consistent curing film formation are determined, and the wet film uniformly formed on the substrate is dried and cured according to the process parameters to obtain a target dry film. In this way, referring to the process parameters obtained by analyzing the macroscopic cavity physical field and the wet film curing in the microscopic sub-pixel groove, the uniformly formed wet film is dried and cured to obtain a target dry film with consistent film thickness and uniform film formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0043] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 A flow chart of the first embodiment of the method for controlling the high-precision film formation consistency of the OLED inkjet printed film of the present application;

[0045] Figure 2 A schematic diagram of the arrangement of components provided in Example 1 of the method for controlling the high-precision film formation consistency of an OLED inkjet-printed film of the present application;

[0046] Figure 3A schematic diagram of a single sub-pixel of a substrate provided in Example 1 of the method for controlling the high-precision film formation consistency of an OLED inkjet-printed film of the present application;

[0047] Figure 4 A schematic diagram of macro-micro coupling simulation provided for Example 1 of the method for controlling the high-precision film formation consistency of OLED inkjet printed thin films of the present application;

[0048] Figure 5 This is a schematic diagram of the module structure of a high-precision film formation consistency control device for an OLED inkjet printed film according to an embodiment of the present application;

[0049] Figure 6 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the high-precision film formation consistency control method for OLED inkjet printed films in the embodiment of the present application.

[0050] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0052] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0053] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device capable of realizing the above functions, an inkjet printing device, etc. The following takes an inkjet printing device as an example to illustrate this embodiment and the following embodiments.

[0054] Based on this, the present application embodiment provides a method for controlling the high-precision film formation consistency of an OLED inkjet printed film, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the high-precision film formation consistency control method for OLED inkjet printed thin films of the present application.

[0055] In this embodiment, the high-precision film formation consistency control method of the OLED inkjet printing film includes steps S10 to S30:

[0056] Step S10, obtaining and obtaining a uniformly formed wet film on the substrate based on the surface morphology data of a single sub-pixel of the substrate and the ink atomization characteristic parameters;

[0057] In one embodiment, referring to Figure 2, a microchannel fluid system and a gradient distributed electric heating element array are integrated inside the aluminum substrate. The microchannel fluid system is used to achieve precise temperature control during vacuum condensation drying, and the gradient distributed electric heating element array is used to quickly heat up to meet the drying requirements of solvents with different boiling points.

[0058] It should be noted that, refer to Figure 3 The surface morphology data of a single sub-pixel of the substrate include the external contact angle θ1, the internal contact angle θ2, the length L, the width W, the depth H and the sub-pixel spacing d. The ink atomization characteristic parameters include the density ρ, the viscosity μ, the surface tension coefficient σ, the ink droplet flight speed v, the ink droplet radius R, and the solubility of the solid content in the ink s.

[0059] In a feasible implementation manner, step S10 includes:

[0060] According to the surface morphology data of a single sub-pixel on the substrate and the ink atomization characteristic parameters, the maximum volume that can be accommodated by the ink droplet in the single sub-pixel slot and the maximum inkjet offset distance are obtained through simulation analysis;

[0061] According to the maximum accommodating volume of ink droplets in a single sub-pixel slot and the maximum inkjet offset distance, ink printing planning is performed to obtain a uniformly formed wet film on the substrate.

[0062] In one embodiment, a simulation numerical model for uniform film formation of a wet film within a single sub-pixel is established, and the ideal ink droplet volume V_ideal within a single sub-pixel (that is, the maximum volume that an ink droplet can accommodate within a single sub-pixel groove) and the maximum offset distance x1 of the ink droplet landing point are output through simulation analysis. The above data can be used to update the printing planning algorithm, and inkjet printing can be performed according to the latest printing planning algorithm to avoid single-sub-pixel ink overflow to cause adjacent single-sub-pixel bridging, scattered point defects caused by excessive landing point deviation, or color interference caused by ink droplets entering adjacent single-sub-pixels, thereby obtaining a large-area, high-precision, uniform wet film.

[0063] Step S20, determining the process parameters for consistent film curing by combining macroscopic cavity physical field simulation analysis and microscopic sub-pixel groove wet film curing simulation analysis;

[0064] After the wet film is uniformly formed on the large-area substrate, the mixed solvent in the wet film is evaporated and solidified into a film through vacuum drying and baking processes. The vacuum drying is carried out in a closed chamber, so macro-micro coupling multi-physics field simulation analysis is carried out.

[0065] In a feasible implementation, in the macroscopic cavity physical field simulation analysis, a uniformly distributed temperature field and airflow field are obtained through simulation calculation and optimization iteration according to initial process parameters.

[0066] It should be noted that before conducting macro-micro coupled multi-physics field simulation analysis, the structural topology optimization of the temperature control system coupled with water cooling and electric heating can be performed, and the temperature control system after structural topology optimization can be simulated and analyzed.

[0067] In one embodiment, the flow channel system and the arrangement of the electric heating elements are optimized by simulation, combined with PID control, to ensure that the flow channel cooling and heating systems can work together to maximize the temperature uniformity and response speed during the drying process of large-area substrates.

[0068] In one embodiment, referring to Figure 4 On a macro level, a complex multi-physics field model in a closed cavity is established based on the temperature control system after structural topology optimization. The process parameters such as the temperature setting value of the cold and hot plates, the vacuum setting value in the cavity, the vacuum change rate and time, and the heating duration are input. The temperature field and pressure field (i.e., airflow field) distribution during the entire process time are output through simulation calculation. The process parameter setting values ​​are continuously optimized and iterated, and finally the uniformly distributed temperature field and airflow field are output.

[0069] In a feasible implementation, in the simulation analysis of wet film curing in the microscopic sub-pixel groove, the dry film morphology after drying and curing is obtained through simulation calculation based on the uniformly distributed temperature field and airflow field and the latest wet film morphology.

[0070] In one embodiment, referring to Figure 4 At the microscopic level, a simulation analysis of wet film curing in microscopic sub-pixels is performed based on the sub-pixel surface morphology data: a sub-pixel multi-physical field coupled phase change model is established, and the temperature field, airflow field distribution and wet film morphology output by the above macroscopic simulation analysis are used as input. The dry film morphology after the drying and curing process is obtained through simulation analysis.

[0071] In a feasible implementation manner, step S20 includes:

[0072] When the dry film morphology obtained by simulation calculation is inconsistent with the target dry film morphology of consistent curing film under ideal conditions, the initial process parameters are optimized until the dry film morphology obtained by simulation calculation is consistent with the target theoretical dry film morphology, thereby obtaining the process parameters of consistent curing film.

[0073] It should be noted that, in theory, the morphology of the simulation output should be a uniform film, but there are differences between the simulation and the actual drying, which leads to errors between the simulation output and the actual output of the microscopic part. Therefore, continuous optimization is required based on the actual output.

[0074] In one embodiment, referring to Figure 4 , according to the target dry film morphology data, the process parameters are continuously optimized and iteratively simulated, and finally high-precision curing film consistency process parameters are output.

[0075] In this embodiment, by performing multi-physics coupling simulation analysis on the film forming process, the key factors in the drying process such as temperature distribution, solvent evaporation rate, gas flow, surface tension and substrate size on the film formation are studied. A multi-physics coupling simulation model based on CFD (Computational Fluid Dynamics) and heat conduction is established to analyze the effects of different solvent boiling points and substrate thermal diffusion characteristics on the drying process, and obtain the influencing rules of the drying process. According to the simulation results, the heating strategies for different areas in the drying process (such as different inlets, outlets and flow rates of the flow channel and adjustment of the electric heating elements) are optimized, and the drying rate is adjusted according to the solvent volatilization characteristics to improve the consistency of the film thickness. Based on the simulation analysis, an adaptive film formation control method is formed to ensure the synchronous drying of different solvents and improve the film formation quality.

[0076] At the same time, the system has good scalability and can adapt to substrates of different sizes and shapes. Whether it is a small-area high-precision display or a large-area display, the system can adjust the corresponding process parameters to meet various process requirements and is suitable for different types of OLED display manufacturing scenarios.

[0077] Step S30 , referring to the process parameters, drying and curing the wet film uniformly formed on the substrate to obtain a target dry film.

[0078] In this embodiment, a multi-physical field coupled precise temperature control system is formed by using a microchannel fluid system and a gradient distributed electric heating element array in combination with an adaptive PID control algorithm, thereby achieving rapid response and uniform control of temperature.

[0079] In a feasible implementation manner, step S30 includes:

[0080] Step S301, taking the temperature of the process parameter as the set temperature, and determining the target control temperature for temperature control of the water cooling system and the electric heating system through PID control;

[0081] Step S302, controlling the coolant flow rate of the water cooling system based on the target control temperature;

[0082] Step S303: performing power control on the electric heating system based on the target control temperature.

[0083] In one embodiment, the integrated PID temperature control system combines the water cooling system and the electric heating system, and dynamically adjusts the coolant flow rate and heating power through the PID adaptive control algorithm to ensure rapid response and precise control of the temperature during the entire drying process. The PID control formula is: u(t) = K_p (T_set1 - T_actual(t)) + K_i ∫(T_set1 - T_actual(t))dt + K_d d / dt (T_set1 - T_actual(t)). Among them, u(t) is the PID control signal, T_actual(t) is the current overall or local temperature, and T_set1 is the target control temperature of the integrated PID temperature control system that combines the water cooling system and the electric heating system.

[0084] In a feasible implementation manner, step S302 includes:

[0085] Obtain the coolant inlet temperature, the amount of heat to be removed during cooling, and the specific heat capacity of the coolant;

[0086] Determine the cooling change temperature according to the target control temperature and the inlet temperature of the coolant;

[0087] Determine the target flow rate of the coolant based on the cooling change temperature, the amount of heat to be removed during the cooling process, and the specific heat capacity of the coolant;

[0088] Control the real-time flow rate of the coolant in the water cooling system at the target flow rate.

[0089] In one embodiment, the geometric design, flow rate and flow rate of the water-cooling channel are optimized by topology optimization algorithm and multi-objective optimization technology to ensure uniform distribution of the coolant, thereby ensuring the temperature uniformity of the large-area substrate. The coolant temperature control formula of the micro-channel system is: T_c(t) = T_in + (Q_cooling) / (m C_p). Wherein, T_c(t) is the control temperature of the coolant in the micro-channel system, that is, the PID control signal u(t) of the comprehensive PID temperature control system combining the water cooling system and the electric heating system, T_in is the inlet temperature of the coolant, Q_cooling is the heat removed during the cooling process, m is the coolant flow rate, and the target flow rate of the coolant can be further determined by the coolant flow rate m, and C_p is the specific heat capacity of the coolant.

[0090] In a feasible implementation manner, step S303 includes:

[0091] Obtain the real-time temperature of the electric heating element in the electric heating system;

[0092] According to the real-time temperature and the target control temperature, the power of the electric heating element in the electric heating system is determined by PID control.

[0093] In one embodiment, a high-precision temperature sensor is arranged near each electric heating element to feedback temperature information in real time and perform power adaptive adjustment through PID control. The power adjustment formula is as follows: P_i(t) = K_p (T_set2 - T_i(t))+ K_i ∫ (T_set2 - T_i(τ)) dτ + K_d d / dt (T_set2 - T_i(t)). Wherein, P_i(t) is the power of the ith electric heating element, T_set2 is the set control temperature of the electric heating system, that is, the PID control signal u(t) of the comprehensive PID temperature control system combining the water cooling system and the electric heating system, T_i(t) is the current temperature of the ith thermocouple, and K_p, K_i, K_d are PID control parameters.

[0094] At present, in the inkjet printing process, the temperature consistency of large-area substrates is the key to determining the quality of thin film formation. Improper temperature control will lead to uneven temperatures in different areas of the substrate, resulting in significant deviations in film thickness, affecting the performance and life of OLED devices.

[0095] In this embodiment, combined with multi-physics field coupling simulation design, the temperature control system can accurately control the temperature in different drying stages. In the vacuum condensation drying stage, the temperature uniformity is controlled within ±0.1°C, and in the high boiling point solvent drying stage, the temperature uniformity is controlled within ±0.5°C. This high-precision temperature control capability ensures temperature consistency during the film formation process and effectively reduces the fluctuation of film thickness.

[0096] In addition, the film-forming process of OLED inkjet printing includes the drying and curing of ink droplets. Traditional drying technologies, such as vacuum condensation drying and hot plate baking, have their own advantages and disadvantages in terms of drying speed and temperature control. Vacuum condensation drying can effectively avoid bubble generation and solvent overflow, but the heating speed is slow; while hot plate baking has a fast heating speed, but the temperature uniformity is poor, which easily leads to inconsistent film thickness.

[0097] In this embodiment, the electric heating element achieves local rapid heating through an adaptive control system, avoiding the temperature unevenness phenomenon commonly seen in traditional heating systems. Through the PID adaptive control system with real-time feedback, the heating power and cooling speed can be quickly adjusted when the temperature changes. Compared with the traditional heating system, the electric heating element achieves local rapid heating through adaptive control, and can adjust the flow rate and heating power of the coolant in real time according to the data of the temperature sensor, avoiding quality problems caused by excessive temperature fluctuations. This rapid response feature can effectively respond to the temperature requirements of different areas during inkjet printing and improve film forming efficiency.

[0098] In a feasible implementation, the method further includes:

[0099] Obtaining the boiling point of the ink solvent of each single sub-pixel of the substrate;

[0100] The power distribution of the electric heating element is adjusted according to the boiling point of the ink solvent of each single sub-pixel on the substrate.

[0101] Currently, the challenges brought by solvent diversity are as follows: the inks used in OLED inkjet printing often contain a variety of solvents with different boiling points, which requires precise temperature control of different areas and solvents during the drying process to prevent uneven solvent evaporation from causing film quality problems.

[0102] In this embodiment, the temperature control system designed to adapt to complex multi-solvent systems is suitable for inkjet printing processes containing a variety of solvents with different boiling points. According to the drying requirements of solvents with different boiling points, the temperature control system can intelligently adjust the power distribution of the electric heating element, that is, adjust the power distribution of the electric heating element according to the boiling point of the ink solvent of each single sub-pixel of the substrate, ensure that the solvent volatilization process is uniform, and avoid film quality problems caused by uneven solvent volatilization.

[0103] In a feasible implementation, the method further includes:

[0104] A gradient distribution strategy is adopted to arrange the electric heating elements in the edge area of ​​the substrate; wherein the arrangement density of the electric heating elements in the edge area of ​​the substrate is greater than that in the non-edge area of ​​the substrate.

[0105] In one embodiment, the simulation design and arrangement of gradient distribution electric heating elements and thermocouples are realized: a gradient distribution strategy is adopted to arrange electric heating elements with higher density in the edge area of ​​the substrate to compensate for the edge heat dissipation effect. At the same time, the layout of the electric heating elements is optimized through simulation to ensure uniform temperature distribution during heating.

[0106] In the above, through the precise temperature control system, including the multi-physics field coupled microchannel fluid system, the gradient distributed electric heating element array and the adaptive PID temperature control system, the problem of inconsistent film thickness caused by uneven temperature of large-area substrates during OLED inkjet printing is solved, the consistency of film thickness on large-area substrates is ensured, and the deviation of film thickness uniformity is controlled within ±1%, thereby improving the manufacturing accuracy and product reliability of OLED displays, such as improving the yield rate in the production process, accelerating the production process, shortening the drying and curing time, thereby improving the overall production efficiency, and reducing the risk of device aging, thereby extending the service life of OLED products.

[0107] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the high-precision film formation consistency control method of the OLED inkjet printed film of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0108] This application also provides a high-precision film formation consistency control device for OLED inkjet printing films, please refer to Figure 5 , the high-precision film formation consistency control device for OLED inkjet printing film includes:

[0109] The wet film module 10 is used to obtain and obtain a uniformly formed wet film on the substrate according to the surface morphology data of a single sub-pixel of the substrate and the ink atomization characteristic parameters;

[0110] The simulation module 20 is used to determine the process parameters of consistent curing film by combining the macroscopic cavity physical field simulation analysis and the microscopic sub-pixel groove wet film curing simulation analysis;

[0111] The dry film module 30 is used to dry and solidify the wet film uniformly formed on the substrate according to the process parameters to obtain a target dry film.

[0112] In one embodiment, the wet membrane module 10 is further used for:

[0113] According to the surface morphology data of a single sub-pixel on the substrate and the ink atomization characteristic parameters, the maximum volume that can be accommodated by the ink droplet in the single sub-pixel slot and the maximum inkjet offset distance are obtained through simulation analysis;

[0114] According to the maximum accommodating volume of ink droplets in a single sub-pixel slot and the maximum inkjet offset distance, ink printing planning is performed to obtain a uniformly formed wet film on the substrate.

[0115] In one embodiment, in the macroscopic cavity physical field simulation analysis, a uniformly distributed temperature field and airflow field are obtained through simulation calculation and optimization iteration according to initial process parameters.

[0116] In one embodiment, in the simulation analysis of wet film curing in the microscopic sub-pixel groove, the dry film morphology after drying and curing is obtained through simulation calculation based on the uniformly distributed temperature field and airflow field and the latest wet film morphology.

[0117] In one embodiment, the simulation module 20 is further configured to:

[0118] When the dry film morphology obtained by simulation calculation is inconsistent with the target dry film morphology of consistent curing film under ideal conditions, the initial process parameters are optimized until the dry film morphology obtained by simulation calculation is consistent with the target theoretical dry film morphology, thereby obtaining the process parameters of consistent curing film.

[0119] In one embodiment, the dry film module 30 is further used for:

[0120] The temperature of the process parameter is used as the set temperature, and the target control temperature for the temperature control of the water cooling system and the electric heating system is determined by PID control;

[0121] Based on the target control temperature, the coolant flow rate of the water cooling system is controlled;

[0122] Based on the target control temperature, the power of the electric heating system is controlled.

[0123] In one embodiment, the dry film module 30 is further used for:

[0124] Obtain the coolant inlet temperature, the amount of heat to be removed during cooling, and the specific heat capacity of the coolant;

[0125] Determine the cooling change temperature according to the target control temperature and the inlet temperature of the coolant;

[0126] Determine the target flow rate of the coolant based on the cooling change temperature, the amount of heat to be removed during the cooling process, and the specific heat capacity of the coolant;

[0127] Control the real-time flow rate of the coolant in the water cooling system at the target flow rate.

[0128] In one embodiment, the dry film module 30 is further used for:

[0129] Obtain the real-time temperature of the electric heating element in the electric heating system;

[0130] According to the real-time temperature and the target control temperature, the power of the electric heating element in the electric heating system is determined by PID control.

[0131] In one embodiment, the OLED inkjet printing film high-precision film formation consistency control device further includes a boiling point module for:

[0132] Obtaining the boiling point of the ink solvent of each single sub-pixel of the substrate;

[0133] The power distribution of the electric heating element is adjusted according to the boiling point of the ink solvent of each single sub-pixel on the substrate.

[0134] In one embodiment, the OLED inkjet printing film high-precision film formation consistency control device further includes an arrangement module for:

[0135] A gradient distribution strategy is adopted to arrange the electric heating elements in the edge area of ​​the substrate; wherein the arrangement density of the electric heating elements in the edge area of ​​the substrate is greater than that in the non-edge area of ​​the substrate.

[0136] The OLED inkjet printing film high-precision film formation consistency control device provided in the present application adopts the OLED inkjet printing film high-precision film formation consistency control method in the above embodiment, which can solve the technical problem of inconsistent film thickness on a large-area substrate. Compared with the prior art, the beneficial effects of the OLED inkjet printing film high-precision film formation consistency control device provided in the present application are the same as the beneficial effects of the OLED inkjet printing film high-precision film formation consistency control method provided in the above embodiment, and other technical features in the OLED inkjet printing film high-precision film formation consistency control device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0137] The present application provides an inkjet printing device, the inkjet printing device comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the high-precision film formation consistency control method for the OLED inkjet printing film in the above-mentioned embodiment 1.

[0138] Reference below Figure 6 , which shows a schematic diagram of the structure of an inkjet printing device suitable for implementing the embodiment of the present application. The inkjet printing device in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 6 The inkjet printing device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0139] like Figure 6As shown, the inkjet printing device may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the inkjet printing device are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. Communication device 1009 can allow the inkjet printing device to communicate wirelessly or wired with other devices to exchange data. Although the figure shows an inkjet printing device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0140] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0141] The inkjet printing device provided by the present application adopts the high-precision film formation consistency control method of the OLED inkjet printing film in the above embodiment, which can solve the technical problem of inconsistent film thickness on a large-area substrate. Compared with the prior art, the beneficial effects of the inkjet printing device provided by the present application are the same as the beneficial effects of the high-precision film formation consistency control method of the OLED inkjet printing film provided by the above embodiment, and the other technical features of the inkjet printing device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0142] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0143] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0144] The present application provides a computer-readable storage medium having computer-readable program instructions (i.e., computer programs) stored thereon, and the computer-readable program instructions are used to execute the high-precision film formation consistency control method of the OLED inkjet printing film in the above-mentioned embodiment.

[0145] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM: Random Access Memory), a read-only memory (ROM: Read Only Memory), an erasable programmable read-only memory (EPROM: Erasable Programmable Read Only Memory or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM: CD-Read Only Memory), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency: Radio Frequency), etc., or any suitable combination of the above.

[0146] The computer-readable storage medium may be included in the inkjet printing device; or may exist independently without being assembled into the inkjet printing device.

[0147] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the inkjet printing device, the inkjet printing device: obtains and obtains a wet film uniformly formed on the substrate based on the surface morphology data of a single sub-pixel of the substrate and the ink atomization characteristic parameters; determines the process parameters for consistent film curing by combining the macroscopic cavity physical field simulation analysis and the microscopic sub-pixel groove wet film curing simulation analysis; and dries and cures the wet film uniformly formed on the substrate with reference to the process parameters to obtain a target dry film.

[0148] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0149] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0150] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0151] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned OLED inkjet printing film high-precision film formation consistency control method, which can solve the technical problem of inconsistent film thickness on a large-area substrate. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the OLED inkjet printing film high-precision film formation consistency control method provided in the above-mentioned embodiment, and will not be repeated here.

[0152] The present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the above-mentioned method for controlling high-precision film formation consistency of OLED inkjet printed films.

[0153] The computer program product provided in this application can solve the technical problem of inconsistent film thickness on a large-area substrate. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as the beneficial effects of the high-precision film consistency control method for OLED inkjet printing thin films provided in the above embodiment, and will not be repeated here.

[0154] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A method for controlling high-precision film formation consistency of an OLED inkjet printed film, characterized in that: The method for controlling high-precision film formation consistency of the OLED inkjet printing film comprises: Obtaining and obtaining a uniformly formed wet film on the substrate based on the single sub-pixel surface morphology data of the substrate and the ink atomization characteristic parameters; By combining the macroscopic cavity physical field simulation analysis with the microscopic sub-pixel groove wet film curing simulation analysis, the process parameters for consistent curing film formation are determined; Referring to the process parameters, drying and curing the wet film uniformly formed on the substrate to obtain a target dry film; The step of obtaining a uniformly formed wet film on the substrate according to the surface morphology data of a single sub-pixel of the substrate and the ink atomization characteristic parameters comprises: According to the surface morphology data of a single sub-pixel on the substrate and the ink atomization characteristic parameters, the maximum volume that can be accommodated by the ink droplet in the single sub-pixel slot and the maximum inkjet offset distance are obtained through simulation analysis; Ink printing planning is performed based on the maximum volume that ink droplets can accommodate in a single sub-pixel slot and the maximum inkjet offset distance to obtain a uniformly formed wet film on the substrate to avoid single-sub-pixel ink overflow to cause adjacent single-sub-pixel bridging, scattered point defects caused by excessive landing deviation, or color crosstalk caused by ink droplets entering adjacent single-sub-pixels.

2. The method for controlling high-precision film formation consistency of an OLED inkjet printed film according to claim 1, characterized in that: In the macroscopic cavity physical field simulation analysis, according to the initial process parameters, uniformly distributed temperature field and airflow field are obtained through simulation calculation and optimization iteration.

3. The method for controlling high-precision film formation consistency of an OLED inkjet printed film according to claim 2, characterized in that: In the simulation analysis of wet film curing in the microscopic sub-pixel groove, the dry film morphology after drying and curing is obtained through simulation calculation based on the uniformly distributed temperature field and airflow field and the latest wet film morphology.

4. The method for controlling high-precision film formation consistency of an OLED inkjet printed film according to claim 1, characterized in that: The step of determining the process parameters for uniform film curing by combining macroscopic cavity physical field simulation analysis and microscopic sub-pixel groove wet film curing simulation analysis includes: When the dry film morphology obtained by simulation calculation is inconsistent with the target dry film morphology of consistent curing film under ideal conditions, the initial process parameters are optimized until the dry film morphology obtained by simulation calculation is consistent with the target theoretical dry film morphology, thereby obtaining the process parameters of consistent curing film.

5. The method for controlling high-precision film formation consistency of an OLED inkjet printed film according to claim 1, characterized in that: The step of drying and curing the wet film uniformly formed on the substrate with reference to the process parameters to obtain a target dry film comprises: The temperature of the process parameter is used as the set temperature, and the target control temperature for temperature control of the water cooling system and the electric heating system is determined by PID control; Based on the target control temperature, controlling the coolant flow rate of the water cooling system; Based on the target control temperature, power control is performed on the electric heating system.

6. The method for controlling high-precision film formation consistency of an OLED inkjet printed film according to claim 5, characterized in that: The step of controlling the coolant flow rate of the water cooling system based on the target control temperature comprises: Obtain the coolant inlet temperature, the amount of heat to be removed during cooling, and the specific heat capacity of the coolant; Determining a cooling change temperature according to the target control temperature and the inlet temperature of the coolant; determining a target flow rate of the coolant according to the cooling change temperature, the amount of heat to be removed during the cooling process, and the specific heat capacity of the coolant; The real-time flow rate of the coolant in the water cooling system is controlled at the target flow rate.

7. The method for controlling high-precision film formation consistency of an OLED inkjet printed film according to claim 5, characterized in that: The step of controlling the power of the electric heating system based on the target control temperature comprises: Obtain the real-time temperature of the electric heating element in the electric heating system; According to the real-time temperature and the target control temperature, the power of the electric heating element in the electric heating system is determined through PID control.

8. The method for controlling high-precision film formation consistency of an OLED inkjet printed film according to claim 7, characterized in that: The method further comprises: Obtaining the boiling point of the ink solvent of each single sub-pixel of the substrate; The power distribution of the electric heating element is adjusted according to the boiling point of the ink solvent of each single sub-pixel on the substrate.

9. The method for controlling high-precision film formation consistency of an OLED inkjet printed film according to claim 7, characterized in that: The method further comprises: The electric heating elements are arranged using a gradient distribution strategy; wherein the arrangement density of the electric heating elements in the edge area of ​​the substrate is greater than the arrangement density of the electric heating elements in the non-edge area of ​​the substrate.

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