BOPP film photoetching label control method and system

Abstract

The invention relates to the technical field of cigarette packaging materials, and discloses a BOPP film photoetching label control method and system.The method comprises the steps that temperature distribution in a photoetching machine is monitored, and the temperature distribution is analyzed to predict the shrinkage amount of a BOPP film in the photoetching stage; triggering a first control operation according to the prediction result; the first control operation comprises the step of executing label photoetching according to a shrinkage control parameter, so that the shrinkage of the BOPP film in the photoetching stage is within a target shrinkage; wherein the shrinkage control parameters comprise exposure energy and developing time. According to the method and the system disclosed by the invention, the shrinkage of the BOPP film in the photoetching stage is predicted by analyzing the temperature distribution in the photoetching machine in real time, and key parameters such as exposure energy and developing time are dynamically adjusted, so that the shrinkage is controlled within a target range, and the problems of pattern deformation and flatness reduction caused by shrinkage of the BOPP film are effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of cigarette packaging materials, in particular to a BOPP film photolithography label control method and system. Background Art

[0002] BOPP (Biaxially oriented polypropylene) is a biaxially oriented polypropylene film with excellent transparency, mechanical strength and barrier properties. It is widely used in packaging, labeling and anti-counterfeiting fields, especially for making cigarette packaging materials. With the continuous improvement of the market's requirements for the appearance quality and anti-counterfeiting performance of cigarette packaging, fine printing and hot stamping on BOPP film has become an industry trend. These processes usually involve photolithography processes to achieve high-precision pattern transfer and surface treatment.

[0003] However, there is a significant technical difficulty in the photolithography process of BOPP film: due to the high and uneven temperature distribution in the photolithography machine, as well as the thermal shrinkage characteristics of the BOPP film itself, the film material will shrink to varying degrees during the photolithography stage. This shrinkage will not only cause pattern deformation and increased line width deviation, but also seriously affect the flatness of the product, thereby reducing the appearance quality and functionality of the packaging. Especially in cigarette packaging, the decrease in flatness may affect the sealing and aesthetics of the packaging, and even cause product operation failures on high-speed packaging machines.

[0004] At present, the industry's solutions to the BOPP film shrinkage problem are mainly focused on material modification (such as reducing thermal shrinkage) and process optimization (such as adding a baking step and adjusting the baking temperature curve). However, these methods often fail to balance production efficiency and quality control, and cannot respond to the impact of temperature fluctuations in the lithography machine on shrinkage in real time. Summary of the invention

[0005] To this end, the present invention aims to overcome the problem of flatness of photolithography products caused by shrinkage of BOPP film in the photolithography stage in the prior art, and provide a BOPP film photolithography label control method and system to effectively improve product flatness.

[0006] In the first aspect, in order to solve the above-mentioned technical problems, the present invention provides a BOPP film photolithography label control method, comprising monitoring the temperature distribution in the photolithography machine, analyzing the temperature distribution to predict the shrinkage of the BOPP film during the photolithography stage; triggering a first control operation according to the prediction result; the first control operation comprises performing label lithography according to a shrinkage control parameter, so that the shrinkage of the BOPP film during the photolithography stage is within a target shrinkage; wherein the shrinkage control parameter comprises exposure energy and development time.

[0007] In one embodiment of the present invention, label lithography is performed according to shrinkage control parameters, including: S10, obtaining a lithography cycle of a BOPP film lithography label, and dividing a plurality of control stages based on the lithography cycle; S20, selecting a first stage and a second stage adjacent thereto, and a second expected shrinkage of the second stage; wherein the first stage is the first control stage in the timing of the plurality of control stages; S30, performing the label lithography of the first stage on the BOPP film to be lithography according to the shrinkage control parameters, and obtaining a transverse shrinkage data set and a longitudinal shrinkage data set of the BOPP film in the lithography stage; S40, evaluating the shrinkage within a predetermined window according to the transverse shrinkage data set and the longitudinal shrinkage data set, and obtaining a first shrinkage at an end node of the first stage; S50, calculating a deviation between the second expected shrinkage and the first shrinkage, and determining a second shrinkage deviation; S60, performing reverse simulation through a simulation tool to satisfy the second shrinkage deviation and the second stage as constraints, and determining a shrinkage control parameter for the second stage; S70, performing the label lithography of the second stage according to the shrinkage control parameter for the second stage.

[0008] In one embodiment of the present invention, after the second stage label lithography is performed according to the second stage shrinkage control parameter, S10 to S70 are iterated and looped until the first control operation is completed.

[0009] In one embodiment of the present invention, determining the shrinkage control parameter includes obtaining the shrinkage control parameter by reverse simulation using a simulation tool, taking the photolithography cycle and the target shrinkage as constraints.

[0010] In one embodiment of the present invention, after the shrinkage amount of the BOPP film in the photolithography stage is optimized to within the target shrinkage amount, it also includes monitoring the quality parameters of the photolithography label and triggering a second control operation according to the quality parameters; the second control operation includes performing label photolithography according to the quality control parameters, so that the quality of the photolithography label is within the target quality; wherein; the quality parameters include the line width and edge roughness of the label pattern.

[0011] In one embodiment of the present invention, the quality control parameters include exposure energy and development time, and obtaining the quality control parameters includes acquiring a line width data set and an edge roughness data set of a photolithography label; performing a first quality assessment on the line width data set within a predetermined window to obtain a first quality index; performing a second quality assessment on the edge roughness data set within a predetermined window to obtain a second quality index; fusing the first quality index and the second quality index to obtain a fused quality index; and operating a PID controller with exposure energy and development time as control parameters and with the goal of minimizing the deviation between the fused quality index and the target quality index to obtain the quality control parameters.

[0012] In one embodiment of the present invention, the shrinkage of the BOPP film in the photolithography stage is predicted by analyzing the temperature distribution based on a pre-constructed thermal shrinkage model; wherein, constructing the thermal shrinkage model includes obtaining a temperature distribution sample set and a BOPP film shrinkage sample set from experimental data; and supervising training the BP neural network with the temperature distribution sample set as input data and the BOPP film shrinkage sample set as output data until the convergence condition is reached to obtain the thermal shrinkage model.

[0013] In one embodiment of the present invention, a first control operation is triggered according to a prediction result, including inputting the temperature distribution into the thermal shrinkage model to obtain a predicted shrinkage value; if the predicted shrinkage value is greater than or equal to the target shrinkage value, the first control operation is triggered.

[0014] In the second aspect, based on the same inventive concept, in order to solve the above-mentioned technical problems, the present invention provides a BOPP film photolithography label control system, including a temperature monitoring module, which monitors the temperature distribution in the photolithography machine in real time; a data analysis module, which analyzes the temperature distribution to predict the shrinkage of the BOPP film during the photolithography stage; a first control operation module, which triggers a first control operation according to the prediction result; the first control operation includes performing label photolithography according to a shrinkage control parameter, so that the shrinkage of the BOPP film during the photolithography stage is within the target shrinkage; wherein the shrinkage control parameter includes exposure energy and development time.

[0015] In one embodiment of the present invention, it also includes a second control operation module, which is used to trigger a second control operation according to the quality parameters of the photolithography label after the shrinkage of the BOPP film in the photolithography stage is optimized to within the target shrinkage; the second control operation includes performing label photolithography according to the quality control parameters so that the quality of the photolithography label is within the target quality.

[0016] The above technical solution of the present invention has the following beneficial effects compared with the prior art: The BOPP film photolithography label control method and system of the present invention predicts the shrinkage of the BOPP film during the photolithography stage by real-time analysis of the temperature distribution in the photolithography machine, and dynamically adjusts key parameters such as exposure energy and development time to ensure that the shrinkage is controlled within the target range, thereby effectively solving the problem of pattern deformation and flatness reduction caused by BOPP film shrinkage. This method can not only improve the accuracy and consistency of photolithography labels, but also adapt to temperature fluctuations under different process conditions, providing reliable technical support for the high-quality production of cigarette packaging materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein: Figure 1 It is a schematic flow chart of a BOPP film photolithography label control method in a preferred embodiment of the present invention; Figure 2 It is a flow chart of performing label lithography according to the shrinkage control parameter in the first control operation of the preferred embodiment of the present invention; Figure 3 It is a schematic flow chart of a BOPP film photolithography label control method in a second embodiment of the present invention; Figure 4 It is a schematic diagram of a flow chart of obtaining quality control parameters in the second control operation of the second embodiment of the present invention; Figure 5 It is a structural block diagram of a BOPP film photolithography label control system in a third embodiment of the present invention; Figure 6 It is a structural block diagram of a BOPP film photolithography label control system in the fourth embodiment of the present invention. DETAILED DESCRIPTION

[0018] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention. Example

[0019] The BOPP film photolithography label control method and system of the present invention are applied to the production of cigarette packaging gold stamping products by BOPP film photolithography. The process of producing cigarette packaging gold stamping products is divided into a photolithography stage and a gold stamping stage. The microstructure corresponding to the gold stamping pattern is formed on the surface of the BOPP film by the photolithography stage. For example, the photoresist is photochemically reacted by ultraviolet light irradiation, thereby forming a concave or convex pattern on the BOPP film. The photolithography stage includes photoresist coating, exposure and development processes: a layer of photoresist is uniformly coated on the surface of the BOPP film by spin coating, brush coating or spray coating. The BOPP film coated with photoresist is placed in a photolithography device and exposed to ultraviolet light (UV) through a mask plate; during exposure, there is a preset gold stamping pattern (such as a trademark, pattern, etc.) on the mask plate. Under ultraviolet light irradiation, the photoresist undergoes a chemical reaction, and the unexposed area remains unchanged, while the exposed area becomes soluble. After the exposure is completed, the unexposed photoresist is removed using a developer, leaving the photoresist film in the pattern area, and these pattern areas will become the "mask" for the subsequent gold stamping process.

[0020] The temperature of the photolithography exposure process is between 80℃ and 120℃. At this temperature, the molecular structure of the BOPP film changes, causing the film to shrink or deform. Especially when the temperature exceeds 100℃, the BOPP film shrinks most significantly. This shrinkage of the BOPP film will not only cause pattern deformation and increased line width deviation, but will also seriously affect the flatness of the product, thereby reducing the appearance quality and functionality of cigarette packaging.

[0021] In view of this technical problem, an embodiment of the present invention discloses a BOPP film photolithography label control method, which aims to solve the problem of flatness of photolithography products caused by shrinkage of BOPP film during the photolithography stage. The technical solution in this application will be clearly and completely described with reference to the accompanying drawings below: Reference Figure 1 As shown, a BOPP film photolithography label control method includes monitoring the temperature distribution in the photolithography machine, analyzing the temperature distribution to predict the shrinkage of the BOPP film in the photolithography stage; triggering a first control operation according to the prediction result; the first control operation includes performing label photolithography according to a shrinkage control parameter, so that the shrinkage of the BOPP film in the photolithography stage is within a target shrinkage; wherein the shrinkage control parameter includes exposure energy and development time.

[0022] The BOPP film photolithography label control method of the present invention predicts the shrinkage of the BOPP film during the photolithography stage by real-time analysis of the temperature distribution in the photolithography machine, and dynamically adjusts key parameters such as exposure energy and development time to ensure that the shrinkage is controlled within the target range, thereby effectively solving the problem of pattern deformation and flatness reduction caused by BOPP film shrinkage. This method can not only improve the accuracy and consistency of photolithography labels, but also adapt to temperature fluctuations under different process conditions, providing reliable technical support for the high-quality production of cigarette packaging materials.

[0023] In specific application scenarios, the temperature distribution in the lithography machine is monitored, and the temperature distribution in the lithography machine is monitored in real time through temperature sensors or infrared imaging technology. For example, multiple high-precision temperature sensors are evenly arranged at key positions inside the lithography machine, such as around the exposure light source, different areas of the workbench, and near the heat dissipation system. These sensors can sense the temperature changes in the lithography machine in real time and transmit the data to the control system. The control system collects the data of each temperature sensor at a preset time interval (for example, once per second) to form a temperature distribution matrix. Then, the collected data is processed through a special data analysis algorithm to analyze the temperature difference and temperature change trend of different areas in the lithography machine, such as interpolation algorithm, statistical analysis algorithm, Fourier transform algorithm, wavelet transform algorithm or machine learning algorithm. Accurately grasp the temperature changes in the lithography process and provide data support for subsequent control operations.

[0024] The shrinkage of the BOPP film in the photolithography stage is predicted according to the analysis results of the temperature distribution, and a thermal shrinkage model is established. The shrinkage of the BOPP film in the photolithography stage is predicted according to the analysis results of the temperature distribution; wherein, the thermal shrinkage model is constructed, including obtaining a temperature distribution sample set and a BOPP film shrinkage sample set from experimental data; and supervised training is performed on a BP neural network using the temperature distribution sample set as input data and the BOPP film shrinkage sample set as output data until the convergence condition is reached to obtain the thermal shrinkage model.

[0025] The experimental data is obtained from a large number of experiments measuring the shrinkage of BOPP film at different temperatures. For example, the temperature range of the experiment is determined according to the material characteristics and application requirements of the BOPP film. Generally, the room temperature (25°C) to the highest temperature (such as 150°C) at which the BOPP film begins to show obvious deformation or damage can be selected, and multiple test temperature points are set at a certain temperature interval (such as 5°C or 10°C). At least 5 repeated experiments are carried out at each temperature point, and the average value is taken as the shrinkage measurement result at that temperature. The fixture containing the BOPP film sample is placed in a constant temperature box or heating furnace, and the temperature is slowly raised to the set test temperature. The heating rate should be controlled at about 1°C / min to avoid thermal shock to the BOPP film caused by rapid temperature changes; during the heating process, the temperature change is monitored in real time by a temperature sensor. When the temperature stabilizes at the set test temperature and remains for 5 minutes, the shrinkage measurement is started. This ensures that the BOPP film is fully in thermal equilibrium and the measurement results are more accurate. Use measuring instruments such as laser displacement sensors or electron microscopes to measure the dimensional changes of the film in the initial state (25°C) and after heating to the set temperature in the direction perpendicular to the surface of the BOPP film. When measuring, ensure that the measuring beam or the focus of the electron microscope is perpendicular to the surface of the film and the measuring position is fixed to ensure the consistency of the measurement results. For laser displacement sensor measurement, align the sensor with a specific position on the surface of the BOPP film, record the displacement value of the initial position, and record the displacement value of the position again when the temperature stabilizes. The difference between the two is the shrinkage of the BOPP film at this temperature. For electron microscope measurement, use an electron microscope to capture the surface images of the BOPP film at different temperatures, use image analysis software to measure the dimensional changes of the film, and calculate the shrinkage.

[0026] The thermal shrinkage model should be understood as constructing a BP neural network architecture based on the structural-thermodynamic model, training the BP neural network architecture through a large amount of experimental data until the convergence conditions are met to obtain the thermal shrinkage model. When the qualified thermal shrinkage model is applied, the temperature distribution data is input to obtain the thermal shrinkage of the BOPP film in the photolithography stage, and the predicted shrinkage value under the current temperature distribution is obtained based on the thermal shrinkage model.

[0027] After obtaining the predicted shrinkage value, if the predicted shrinkage value is greater than or equal to the target shrinkage value, a first control operation is triggered; the first control operation includes performing label lithography according to the shrinkage control parameters, so that the shrinkage of the BOPP film in the lithography stage is within the target shrinkage amount; wherein the shrinkage control parameters include exposure energy and development time.

[0028] The target shrinkage is related to the flatness of the final product and the quality of the photolithography pattern (such as line width, edge roughness, etc.). The target shrinkage of the BOPP film of the current product is determined in advance based on these related items. If the predicted shrinkage value is within the target shrinkage value, the photolithography operation continues to be performed according to the current process parameters; if the predicted shrinkage value reaches or even exceeds the target shrinkage value, it indicates that the influence of the current temperature distribution on the shrinkage of the BOPP film will cause the product to be unqualified, thereby triggering the first control operation to perform intervention control so that the shrinkage of the BOPP film in the photolithography stage is within the target shrinkage value.

[0029] The first control operation includes controlling the exposure energy and the development time. The path by which the exposure energy affects the shrinkage of the BOPP film includes that when the exposure energy (also known as "ultraviolet light energy") acts on the BOPP film, the molecules in the BOPP film absorb the photon energy, and the vibration and rotation of the molecules intensify, causing the film temperature to rise and cause thermal expansion. After the exposure is completed, the film begins to cool and shrink. The greater the exposure energy, the greater the temperature rise of the film, and the greater the shrinkage after cooling. When the predicted shrinkage of the BOPP film exceeds the target shrinkage, the exposure energy is reduced to compensate for the shrinkage. After reducing the exposure energy, the shrinkage of the film is reduced accordingly. At this time, the development time is adjusted to maintain the appropriate shrinkage: shorten the development time to prevent insufficient dissolution of the photoresist from causing an uneven film surface, which in turn affects the shrinkage.

[0030] Specifically, Figure 2As shown, in one embodiment, performing label lithography according to the shrinkage control parameter includes the following steps: S10, obtaining the lithography cycle of the BOPP film lithography label, and dividing it into multiple control stages based on the lithography cycle; S20, selecting the first stage and the second stage adjacent to it, and the second expected shrinkage of the second stage; wherein the first stage is the first control stage in the timing of the multiple control stages; S30, performing the label lithography of the first stage on the BOPP film to be lithography according to the shrinkage control parameter, and obtaining the lateral shrinkage data set and the longitudinal shrinkage data set of the BOPP film in the lithography stage; S40, evaluating the shrinkage within a predetermined window according to the lateral shrinkage data set and the longitudinal shrinkage data set, and obtaining the first shrinkage of the end node of the first stage; S50, calculating the deviation between the second expected shrinkage and the first shrinkage, and determining the second shrinkage deviation; S60, performing reverse simulation through a simulation tool to meet the second shrinkage deviation and the second stage as constraints, and determining the shrinkage control parameter of the second stage; S70, performing the label lithography of the second stage according to the shrinkage control parameter of the second stage.

[0031] In a specific application scenario, step S10, obtain the photolithography cycle of the BOPP film photolithography label, and divide it into multiple control stages based on the photolithography cycle. The photolithography cycle is the entire process from the start of exposure to the end of development and the expected photolithography time set. Those skilled in the art can set it according to the actual situation, such as setting the expected photolithography time to 2 hours; divide the photolithography cycle into multiple control stages according to the predetermined time step, and the predetermined time step is set according to the actual situation, for example, the predetermined time step is set to 5 minutes, and multiple control stages are obtained; wherein the multiple control stages have a temporal sequence.

[0032] Next, S20, select the first stage and the second stage adjacent thereto, and the second expected shrinkage of the second stage; wherein the first stage is the first control stage in the timing of the multiple control stages; the second expected shrinkage is the expected shrinkage of the BOPP film at the end of the second stage. After the first stage is finished, the second stage closely adjacent thereto is selected, and the parameters of the second stage must be adjusted based on the shrinkage result of the first stage; the shrinkage target of the second stage is adjusted according to the shrinkage of the film after the photolithography of the first stage is finished. The continuity between different control stages is ensured by associating the stages in this way, and the expected target of the next stage can be adjusted according to the actual effect of the previous stage.

[0033] Before executing the first control operation, it is necessary to determine the shrinkage control parameters. The shrinkage control parameters are determined by taking the photolithography cycle and the target shrinkage as constraints, and reversely simulating through the simulation tool to obtain the shrinkage control parameters. First, select a simulation tool suitable for the photolithography process, such as COMSOL Multiphysics. COMSOL can simulate physical properties such as temperature changes, film shrinkage, and stress distribution during the photolithography process; secondly, according to the material properties of the BOPP film, the principles of the photolithography process, and a photolithography process simulation model is established. The model should be able to accurately simulate the shrinkage behavior and photolithography effect of the BOPP film under different shrinkage control parameters. Then, the photolithography cycle and target shrinkage are input into the simulation tool, and the exposure energy and development time are automatically adjusted. Through iterative simulation, the exposure energy and development time are continuously adjusted until the shrinkage of the BOPP film in the photolithography stage reaches the target shrinkage, and the exposure energy and development time that meet the photolithography cycle and target shrinkage are output. This is used as the shrinkage control parameter to provide a basis for the first control operation.

[0034] S30, further according to the shrinkage control parameters, perform the first stage of label lithography on the BOPP film to be lithography, and obtain the transverse shrinkage data set and the longitudinal shrinkage data set of the BOPP film in the lithography stage. According to the above determined shrinkage control parameters (including exposure energy and development time), the first stage of label lithography is performed on the BOPP film to be lithography, and predetermined monitoring nodes are configured, wherein the time intervals of adjacent monitoring nodes are the same, which can be set according to demand, such as monitoring every 30 seconds, and in the first stage of lithography, a laser measurement system is used, such as a laser sensor that can be installed in the transverse and longitudinal directions of the BOPP film, and the transverse and longitudinal shrinkage amounts are monitored in real time at the predetermined monitoring nodes by scanning the surface of the film and recording the length change before and after shrinkage, and the transverse shrinkage data set and the longitudinal shrinkage data set are obtained.

[0035] S40, further evaluating the shrinkage amount within a predetermined window according to the transverse shrinkage data set and the longitudinal shrinkage data set, and obtaining the first shrinkage amount at the end node of the first stage. Within a predetermined time window (such as the time window of the entire first stage), the average values ​​of the transverse shrinkage data set and the longitudinal shrinkage data set are calculated respectively as the shrinkage amount of the BOPP film in the transverse and longitudinal directions at the end of the stage, that is, the transverse component and the longitudinal component of the first shrinkage amount; according to the preset weight coefficient, the transverse shrinkage amount and the longitudinal shrinkage amount are weighted and summed to obtain the first shrinkage amount at the end node of the first stage. Through this step, it can be determined whether the shrinkage amount reaches the predetermined target value and whether there is a deviation.

[0036] S50, calculating the deviation between the second expected shrinkage and the first shrinkage to determine the second shrinkage deviation. According to a preset deviation calculation method (such as the Euclidean distance method), the comprehensive deviation between the second expected shrinkage and the first shrinkage is calculated. This deviation value reflects the error generated in the photolithography process and provides an adjustment basis for the subsequent control stage.

[0037] Then, S60, with the second shrinkage deviation and the second stage as constraints, reverse simulation is performed through the simulation tool to determine the shrinkage control parameters of the second stage. According to the material properties of the BOPP film, the principle of the photolithography process and the actual photolithography data of the first stage, a simulation model of the photolithography process of the second stage is established, and the second shrinkage deviation and the process requirements of the second stage (such as photolithography time, temperature, etc.) are input into the simulation model of the second stage as constraints. By adjusting the exposure energy and development time in the simulation model, multiple reverse simulation calculations are performed to find a set of shrinkage control parameters that can meet the second shrinkage deviation constraint and optimize the photolithography effect as the second stage shrinkage control parameters; then the second stage label photolithography is performed according to the second stage shrinkage control parameters. The precision of the shrinkage control can be improved, and the technical goal of quickly and accurately adjusting the exposure energy and development time according to the shrinkage state of the BOPP film can be achieved.

[0038] Furthermore, the embodiment of the present application also includes iterating the loop S10 to S70 after executing the second stage of label lithography according to the second stage shrinkage control parameter until the first control operation is completed.

[0039] In a specific application scenario, after the second stage of label lithography is performed according to the second stage shrinkage control parameters, the same method is used to iterate and cycle S10 to S70, and the shrinkage control parameters of the third stage, the fourth stage and the subsequent stages are continuously optimized and adjusted until the first control operation is completed, so that the shrinkage of the BOPP film in the lithography stage is within the target shrinkage. By performing iterative feedback control, the quality and performance of label lithography can be ensured to be stable throughout the first control cycle, and ultimately meet the predetermined design requirements. Example

[0040] The difference between the embodiment of the present invention and the first embodiment is that after the first embodiment is completed, that is, after the shrinkage of the BOPP film in the photolithography stage is optimized to within the target shrinkage, further optimization is included. The premise of the optimization is that even if the shrinkage of the BOPP film is effectively controlled, in the actual production process, the changes in exposure energy and development time will still affect the quality of the photolithography label. The magnitude of the exposure energy affects the photosensitivity and curing effect of the photoresist, and thus affects the formation of the label pattern; the length of the development time determines the degree of dissolution and removal of the photoresist, and plays an important role in the details and edge quality of the pattern. Changes in these factors will cause deviations in quality parameters such as line width and edge roughness of the label pattern, making it difficult to stably control the label quality within the target quality.

[0041] To solve the above problems, refer to Figure 3 As shown, an embodiment of the present invention provides a BOPP film photolithography label control method, which, after the shrinkage control of the BOPP film is stabilized, also includes monitoring the quality parameters of the photolithography label, and triggering a second control operation according to the quality parameters; the second control operation includes performing label photolithography according to the quality control parameters, so that the quality of the photolithography label is within the target quality; wherein; the quality parameters include the line width and edge roughness of the label pattern.

[0042] On the one hand, by precisely controlling the shrinkage of the BOPP film during the photolithography stage, the shrinkage is optimized to within the target shrinkage, thus avoiding the deviation of the label pattern size caused by film shrinkage. On the other hand, by further monitoring the quality parameters of the photolithography label and triggering the second control operation according to the quality parameters, the label photolithography process can be adjusted in real time to compensate for the impact caused by changes in exposure energy and development time, thereby effectively improving the stability of label quality and ensuring that the quality of each label can be maintained within the target quality.

[0043] Furthermore, the quality control parameters include exposure energy and development time, referring to Figure 3 As shown, obtaining the quality control parameters includes acquiring a line width data set and an edge roughness data set of a lithography label; performing a first quality evaluation within a predetermined window on the line width data set to obtain a first quality index; performing a second quality evaluation within a predetermined window on the edge roughness data set to obtain a second quality index; fusing the first quality index and the second quality index to obtain a fused quality index; and operating a PID controller with exposure energy and development time as control parameters and with the goal of minimizing the deviation between the fused quality index and the target quality index to obtain the quality control parameters.

[0044] In specific application scenarios, a high-resolution electron microscope SEM or laser profiler is used to scan and measure the line width of the label pattern after the lithography is completed to obtain the line width data; the microscopic morphology of the edge of the label pattern is measured by an atomic force microscope AFM or an optical interferometer to obtain the edge roughness data. The line width data set and the edge roughness data set record the measured line width and roughness of the label pattern at different positions, respectively, covering the entire label pattern area. Set a predetermined window range, such as a specific area of ​​the entire label area or the central area of ​​the label, to evaluate the line width. The first quality indicator may include the average value, standard deviation, or other indicators for evaluating the pattern accuracy of the line width. Based on these indicators, evaluate whether the line width of the lithography label meets the target specifications. Set an analysis window, such as a specific area of ​​the pattern edge, and calculate the roughness index of each edge. The second quality indicator may include the mean, maximum, minimum, etc. of the edge roughness. Using these data, it is determined whether the edge of the label pattern meets the target requirements and whether there is excessive roughness. The quality assessment results of line width and edge roughness are fused into a comprehensive quality index. For example, the first quality index and the second quality index can be weighted and summed according to the preset weights to obtain a fused quality index; the weights can be adjusted according to the relative importance of line width and edge roughness to the label function and appearance. The proportional-integral-differential (PID) control algorithm is used to adjust the exposure energy and development time to obtain the quality control parameters according to the deviation between the fused quality index and the target quality index.

[0045] It should be noted that after the shrinkage control of the BOPP film is stabilized and the label quality is outside the target, the second control operation is triggered. The control objects of the first control operation and the second control operation are both exposure energy and development time. After the shrinkage control of the BOPP film is stabilized, the exposure energy and development time are adjusted in small steps. That is to say, the adjustment amplitude of the second control operation is smaller than the minimum adjustment amplitude of the first control operation. In this way, the adjustment balance between the label quality and the flatness of the BOPP film is achieved, and finally the label flatness, line width and edge roughness all meet the target requirements. Example

[0046] Based on the same inventive concept as that of the first embodiment, the present invention provides a BOPP film photolithography label control system, referring to Figure 5 As shown, it includes a temperature monitoring module for real-time monitoring of the temperature distribution in the lithography machine; a data analysis module for analyzing the temperature distribution to predict the shrinkage of the BOPP film during the lithography stage; a first control operation module for triggering a first control operation according to the prediction result; the first control operation includes performing label lithography according to a shrinkage control parameter, so that the shrinkage of the BOPP film during the lithography stage is within the target shrinkage; wherein the shrinkage control parameter includes exposure energy and development time.

[0047] The BOPP film photolithography label control system of the embodiment of the present invention is used to execute the BOPP film photolithography label control method in the first embodiment, and has the same technical effect as the first embodiment, which will not be repeated here. Example

[0048] The only difference between the embodiment of the present invention and the third embodiment is that, on the basis of the third embodiment, it also includes a second control operation module, and the second control operation module is used to trigger a second control operation according to the quality parameters of the photolithography label after the shrinkage of the BOPP film in the photolithography stage is optimized to within the target shrinkage; the second control operation includes performing label photolithography according to the quality control parameters so that the quality of the photolithography label is within the target quality.

[0049] The BOPP film photolithography label control system of the embodiment of the present invention is used to execute the BOPP film photolithography label control method in the second embodiment, and has the same technical effect as the second embodiment, which will not be repeated here.

[0050] In summary, the BOPP film photolithography label control method and system of the present invention predicts the shrinkage of the BOPP film during the photolithography stage by real-time analysis of the temperature distribution in the photolithography machine, and dynamically adjusts key parameters such as exposure energy and development time to ensure that the shrinkage is controlled within the target range, thereby effectively solving the problem of pattern deformation and flatness reduction caused by BOPP film shrinkage. This method can not only improve the accuracy and consistency of photolithography labels, but also adapt to temperature fluctuations under different process conditions, providing reliable technical support for the high-quality production of cigarette packaging materials.

[0051] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0052] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0053] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0054] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0055] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A BOPP film photolithography label control method, characterized in that: include, Monitor the temperature distribution in the lithography machine and analyze the temperature distribution to predict the shrinkage of the BOPP film during the lithography stage; A first control operation is triggered according to the prediction result; the first control operation includes performing label lithography according to a shrinkage control parameter, so that the shrinkage of the BOPP film during the lithography stage is within a target shrinkage; wherein the shrinkage control parameter includes exposure energy and development time.

2. The BOPP film photolithography label control method according to claim 1, characterized in that: Perform label lithography according to shrinkage control parameters, including, S10, obtaining a photolithography cycle of the BOPP film photolithography label, and dividing the photolithography cycle into a plurality of control stages; S20, selecting the first stage and the second stage adjacent thereto, and the second expected shrinkage amount of the second stage; wherein the first stage is the first control stage in the time sequence of the multiple control stages; S30, performing the first stage of label photolithography on the BOPP film to be photolithography according to the shrinkage control parameter, and obtaining a transverse shrinkage data set and a longitudinal shrinkage data set of the BOPP film in the photolithography stage; S40, evaluating the shrinkage amount within a predetermined window according to the transverse shrinkage data set and the longitudinal shrinkage data set to obtain a first shrinkage amount of the end node of the first stage; S50, calculating the deviation between the second expected shrinkage amount and the first shrinkage amount to determine a second shrinkage amount deviation; S60, determining the second stage shrinkage control parameters by performing reverse simulation through a simulation tool to meet the second shrinkage deviation and the second stage as constraints; S70 , performing the second-stage label lithography according to the second-stage shrinkage control parameter.

3. The BOPP film photolithography label control method according to claim 2, characterized in that: After the second stage of label lithography is performed according to the second stage shrinkage control parameter, S10 to S70 are iterated until the first control operation is completed.

4. The BOPP film photolithography label control method according to claim 2 or 3, characterized in that: Determining the shrinkage control parameter includes obtaining the shrinkage control parameter by reverse simulation using a simulation tool based on constraints of satisfying the lithography cycle and the target shrinkage.

5. The BOPP film photolithography label control method according to claim 1, characterized in that: After the shrinkage of BOPP film in the photolithography stage is optimized to within the target shrinkage, it also includes: Monitor the quality parameters of the photolithography label and trigger a second control operation according to the quality parameters; the second control operation includes performing label photolithography according to the quality control parameters so that the quality of the photolithography label is within the target quality; wherein; the quality parameters include the line width and edge roughness of the label pattern.

6. The BOPP film photolithography label control method according to claim 5, characterized in that: The quality control parameters include exposure energy and development time, and obtaining the quality control parameters includes: Obtaining a line width dataset and an edge roughness dataset of a lithography label; Performing a first quality assessment on the line width data set within a predetermined window to obtain a first quality indicator; Performing a second quality evaluation within a predetermined window on the edge roughness data set to obtain a second quality index; fusing the first quality indicator and the second quality indicator to obtain a fused quality indicator; The PID controller is operated with exposure energy and development time as control parameters and with the goal of minimizing the deviation between the fusion quality index and the target quality index to obtain the quality control parameters.

7. The BOPP film photolithography label control method according to claim 1, characterized in that: The shrinkage of the BOPP film during the photolithography stage is predicted by analyzing the temperature distribution based on a pre-built thermal shrinkage model; wherein building the thermal shrinkage model includes: Obtaining a temperature distribution sample set and a BOPP film shrinkage sample set from experimental data; The BP neural network is supervised and trained with the temperature distribution sample set as input data and the BOPP film shrinkage sample set as output data until the convergence condition is reached to obtain the thermal shrinkage model.

8. The BOPP film photolithography label control method according to claim 7, characterized in that: Triggering a first control operation according to the prediction result includes: Inputting the temperature distribution into the thermal shrinkage model to obtain a predicted value of shrinkage; If the predicted contraction amount is greater than or equal to the target contraction amount, the first control operation is triggered.

9. A BOPP film photolithography label control system, characterized in that: include, Temperature monitoring module, real-time monitoring of temperature distribution inside the lithography machine; A data analysis module, analyzing the temperature distribution to predict the shrinkage of the BOPP film during the photolithography stage; The first control operation module triggers a first control operation according to the prediction result; the first control operation includes performing label lithography according to a shrinkage control parameter, so that the shrinkage of the BOPP film during the lithography stage is within a target shrinkage; wherein the shrinkage control parameter includes exposure energy and development time.

10. The BOPP film photolithography label control system according to claim 9, characterized in that: It also includes a second control operation module, which is used to trigger a second control operation according to the quality parameters of the photolithography label after the shrinkage of the BOPP film in the photolithography stage is optimized to within the target shrinkage; the second control operation includes performing label photolithography according to the quality control parameters so that the quality of the photolithography label is within the target quality.

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