Aluminum film coating method, equipment and system for plastic packaging bags

Abstract

The present application relates to the technical field of packaging bag coating, and specifically to a method, device and system for aluminum coating of plastic packaging bags, the method comprising: using an inert gas to perform glow cleaning treatment on the plastic packaging bag film; setting the machine parameters for aluminum coating of the plastic packaging bag under a vacuum environment, aluminum coating the plastic packaging bag and judging whether the aluminum coating treatment is normal, the process is: obtaining optical density data and performing peak detection, combining the difference between peak data and non-peak data with data distribution and coordinate distribution to obtain a thickness unevenness factor, and clustering, according to the difference in optical density data distribution in the clustering cluster and the distance of the cluster center, obtaining an aluminum coating unevenness factor; obtaining an aluminum coating adjustment factor for each vacuum aluminum coating interval; judging whether the aluminum coating treatment in the corresponding vacuum aluminum coating interval is normal. The present application aims to reflect the uniformity of aluminum molecule deposition on the surface of plastic packaging bags and improve the accuracy of the judgment results.

Description

Technical Field

[0001] The present application relates to the technical field of packaging bag coating, and in particular to a method, equipment and system for coating aluminized film on plastic packaging bags. Background Art

[0002] Aluminum-coated film for plastic packaging bags is a composite flexible packaging material with bright metallic color formed by coating a very thin layer of metal aluminum on the surface of plastic film using a special process. Aluminum-coated film for plastic packaging bags has excellent folding resistance and good toughness, rarely has pinholes and cracks, no bending and cracking, and has high barrier properties for gas, water vapor, odor, light, etc., and is widely used in food, medicine, cosmetics and other fields.

[0003] The most commonly used aluminum coating method in traditional technology is vacuum aluminum coating, that is, melting and evaporating metal aluminum at high temperature under high vacuum conditions, and when the plastic film passes through the vacuum evaporation chamber, the gaseous aluminum molecules are precipitated on the surface of the plastic film. However, during the vacuum aluminum coating process of plastic packaging bags, the presence of impurities in the evaporation boat or the excessively fast aluminum feeding speed will cause uneven deposition of aluminum molecules on the plastic film, resulting in irregular stripes and even holes on the surface of the plastic film of the packaging bag. The existing technology lacks an accurate evaluation method for the uniformity of aluminum molecule deposition on the surface of the plastic film, which makes it impossible to provide scientific data assistance for the aluminum coating process of plastic packaging bags, and timely adjust the relevant parameters of the aluminum coating film, which affects the sealing and barrier properties of the plastic packaging bags. Summary of the invention

[0004] In view of the above, it is necessary to provide a method, equipment and system for aluminizing plastic packaging bags to solve the above problems.

[0005] According to one aspect of the present application, a method for aluminizing a plastic packaging bag is provided, the method comprising:

[0006] Use inert gas to perform glow cleaning on plastic packaging bag films;

[0007] Under vacuum environment, set the temperature parameters and speed parameters of the machine when aluminizing plastic packaging bags, aluminize the plastic packaging bags and determine whether the aluminizing process is normal;

[0008] The process of judging whether the aluminum coating process is normal is as follows:

[0009] Obtain the optical density data of each plastic packaging bag to be inspected on each scanning line at each moment;

[0010] Perform peak detection on all optical density data on each scan line. For each scan line, the difference between the peak data and the non-peak data is combined with the distribution of all optical density data on each scan line and the distribution of the peak data coordinates to obtain the thickness non-uniformity factor of each scan line.

[0011] Cluster all scan lines of each plastic packaging bag to be inspected based on the thickness non-uniformity factor, and obtain the aluminum plating non-uniformity factor of each plastic packaging bag to be inspected according to the difference in the distribution of optical density data in all the clustering clusters of each pairwise combination of the plastic packaging bag to be inspected and the distance of the cluster center; take the preset time length as a vacuum aluminum plating interval, and obtain the aluminum plating film adjustment factor of each vacuum aluminum plating interval according to the distribution characteristics and change characteristics of all aluminum plating non-uniformity factors in each vacuum aluminum plating interval;

[0012] Based on the aluminum coating adjustment factor, it is determined whether the aluminum coating process in the corresponding vacuum aluminum coating section is normal.

[0013] Wherein, the glow cleaning treatment time is 5 to 10 minutes.

[0014] The temperature parameters and speed parameters of the machine when setting the aluminum film of the plastic packaging bag are specifically:

[0015] When the plastic packaging bag is aluminized, the temperature of the coating drum is set to 0~2°C, the temperature of the evaporation boat is set to 1200~1400°C, the wire feeding speed of the aluminum wire is set to 220~260mm / min, and the winding speed of the coating is set to 5~10m / s.

[0016] The thickness non-uniformity factor of each scanning line is obtained as follows:

[0017] For each scan line, the peak data volatility of each scan line is obtained according to the difference between each peak data and non-peak data, combined with the difference between each trough data and non-peak data;

[0018] Obtain the degree of dispersion of all optical density data on each scanning line, recorded as the first dispersion degree; obtain the degree of disorder of coordinates corresponding to all peak and trough data on each scanning line; based on the first dispersion degree and the disorder degree, obtain the degree of optical density abnormality of each scanning line; wherein the degree of optical density abnormality is positively correlated with the dispersion degree and negatively correlated with the disorder degree;

[0019] The normalized value of the product of the peak data fluctuation of each scan line and the optical density abnormality degree is taken as the thickness non-uniformity factor of each scan line.

[0020] The peak value data volatility of each scan line is obtained as follows:

[0021] Obtain the sum of the absolute values ​​of the differences between each peak data and the non-peak data, recorded as the first difference; obtain the sum of the absolute values ​​of the differences between each trough data and the remaining non-peak data, recorded as the second difference; fuse the first difference and the second difference as the peak data volatility of each scan line.

[0022] The process of obtaining the aluminum plating unevenness factor of each plastic packaging bag to be tested includes:

[0023] The mean of all optical density data corresponding to all scanning lines in each cluster is obtained, and recorded as the optical density mean of each cluster; the differences between the optical density means of all pairwise combinations of clusters in each plastic packaging bag to be detected are fused to obtain a third difference; the parallel distances between the scanning lines corresponding to the cluster centers of all pairwise combinations of clusters in each plastic packaging bag to be detected are fused to obtain a parallel distance fusion result; the product of the third difference and the parallel distance fusion result is used as the aluminum plating unevenness factor of each plastic packaging bag to be detected.

[0024] The step of obtaining the aluminum film adjustment factor of each vacuum aluminum coating interval includes:

[0025] Obtain the discrete degree of the aluminum plating unevenness factor of all the plastic packaging bags to be tested corresponding to each vacuum aluminum plating interval, recorded as the second discrete degree; merge the differences in the aluminum plating unevenness factors of all adjacent plastic packaging bags to be tested in each vacuum aluminum plating interval to obtain a fourth difference; and use the normalized value of the product of the fourth difference and the second discrete degree as the aluminum plating film adjustment factor of each vacuum aluminum plating interval.

[0026] The method of judging whether the aluminum coating process in the corresponding vacuum aluminum coating section is normal is as follows:

[0027] When the aluminum coating adjustment factor of the vacuum aluminum coating section is less than the preset aluminum coating adjustment threshold, it is determined that the aluminum coating process of the vacuum aluminum coating section is normal; otherwise, it is determined that the aluminum coating process of the vacuum aluminum coating section is abnormal.

[0028] According to another aspect of the present application, there is provided an aluminum film coating system for plastic packaging bags, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above methods when executing the computer program.

[0029] According to another aspect of the present application, there is provided an aluminized film coating device for plastic packaging bags, wherein a computer program is stored in the device, and when the computer program is executed by a processor, any one of the aluminized film coating methods described above is implemented.

[0030] This application has at least the following beneficial effects:

[0031] The present application obtains a thickness non-uniformity factor through the fluctuation of optical density data and data anomaly characteristics corresponding to the scanning line of the plastic packaging bag, comprehensively considers the optical density peak data fluctuation characteristics and optical density anomaly characteristics of each scanning line area on the surface of the plastic packaging bag, and more accurately reflects the non-uniform thickness of aluminum molecule deposition on the surface of the plastic packaging bag corresponding to the scanning line area; based on the thickness non-uniformity factor, all scanning lines of each plastic packaging bag to be detected are clustered, and the aluminized film adjustment factor is obtained through the non-uniform thickness characteristics of the aluminized film between the clusters and the non-uniform timing characteristics of the aluminized film, and the vacuum aluminized treatment of the plastic packaging bag is judged based on this, and on the basis of considering the non-uniform condition of the overall aluminized film of the plastic packaging bag, the trend of the non-uniform condition of the aluminized film within the time series interval is considered, which more accurately reflects the uniformity of the deposition of aluminum molecules on the surface of the plastic packaging bag, improves the accuracy of the judgment result, and provides scientific data support for subsequent auxiliary relevant personnel to timely adjust the aluminized film processing process of the plastic packaging bag, avoiding the disadvantage that the sealing and barrier properties are damaged due to the non-uniform aluminized film of the plastic packaging bag. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A flowchart of the steps of a method for aluminizing a plastic packaging bag provided in this application;

[0033] Figure 2 A schematic diagram of peak detection of local optical density values ​​of a scanning line of a plastic packaging bag to be detected provided in this application;

[0034] Figure 3 A schematic diagram of the process for determining whether the aluminum coating process is normal provided in this application. DETAILED DESCRIPTION

[0035] In the description of the embodiments of the present application, words such as "exemplary", "or", "for example" and the like are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "or", "for example" and the like is intended to present related concepts in a concrete manner.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the present application. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0037] It should also be noted that the terms "first" and "second" in this application and the accompanying drawings are used to distinguish similar objects, rather than to describe a specific order or sequence. The method disclosed in the embodiments of the present application or the method shown in the flowchart includes one or more steps for implementing the method. Without departing from the scope of the present application, the execution order of multiple steps can be interchanged with each other, and some steps can also be deleted.

[0038] See also Figure 1 , which shows a flowchart of a method for aluminizing a plastic packaging bag provided by an embodiment of the present application, the method comprising the following steps:

[0039] Step 1: Use inert gas ions to glow clean the plastic packaging bag film.

[0040] The plastic packaging bag substrate to be coated is placed on the unwinding shaft and fixed on the die-threading belt. 15 evaporation boats made of carbon diboride are installed in the vacuum box, and 15 reels of aluminum wire with a purity of more than 99.99% are installed in the vacuum box. After closing the vacuum box, an inert gas is introduced into the vacuum evaporation machine. The inert gas is argon or helium with a mass purity greater than 99.999%. The plastic packaging bag film is glow cleaned for 5 to 10 minutes using inert gas ions to remove organic pollutants on the surface of the plastic film and improve the surface cleanliness.

[0041] Step 2: Under vacuum environment, set the temperature parameters and speed parameters of the machine when aluminizing the plastic packaging bag, aluminize the plastic packaging bag and determine whether the aluminizing process is normal.

[0042] A vacuum pump is used to create a vacuum environment. In this embodiment, the vacuum degree in the vacuum evaporation machine for plastic packaging bags reaches , the temperature of the coating drum is set to 0°C, the temperature of the evaporation boat is set to 1200°C, the wire feeding speed of the aluminum wire is 220mm / min, and the winding speed of the coating is set to 5m / s; in other embodiments, the vacuum degree is , the temperature of the coating drum is set to 0°C, the temperature of the evaporation boat is set to 1250°C, the wire feeding speed of the aluminum wire is 250mm / min, and the winding speed of the coating is set to 5m / s; in some other embodiments, the vacuum degree reaches , the coating drum temperature is set to 2°C, the evaporation boat temperature is set to 1400°C, the aluminum wire feeding speed is set to 260mm / min, and the coating winding speed is set to 10m / s. In this application, the width of the plastic packaging bag to be coated with aluminum film ranges from 1000mm to 5000mm.

[0043] Since the vacuum aluminum plating process of plastic packaging bags is a well-known technology, the specific process will not be described in detail.

[0044] The process of judging whether the aluminum coating process is normal is as follows:

[0045] The first sub-step: obtaining the optical density data of each plastic packaging bag to be inspected on each scanning line at each moment.

[0046] The optical density data of the aluminum-plated film at various positions on the surface of the plastic packaging bag are collected by an optical densitometer. The specific collection method is as follows: the plastic packaging bag to be tested is placed flat on the measurement window of the optical densitometer, and the optical density data of different positions of the plastic packaging bag are acquired from left to right by the probe of the optical densitometer in a line scanning manner. The optical density data on a scanning line is acquired at each moment, and the parallel distance between each scanning line of the probe is 1 cm. The implementer can adjust it according to the actual situation, and the sequence composed of the optical density data on each scanning line of the plastic packaging bag in the order of arrangement is recorded as the optical density data sequence of each scanning line.

[0047] The second sub-step: perform peak detection on all optical density data on each scan line. For each scan line, the difference between the peak data and the non-peak data is combined with the distribution of all optical density data on each scan line and the distribution of the peak data coordinates to obtain the thickness non-uniformity factor of each scan line.

[0048] During the vacuum aluminum plating process of plastic packaging bags, the presence of impurities in the evaporation boat will cause the plastic packaging bags to be contaminated by impurities during the vacuum aluminum plating process. The impurities will evaporate together with the aluminum molecules during the evaporation process and deposit on the plastic film. When the aluminum feeding speed is too fast, it may affect the deposition and solidification process of the aluminum molecules on the surface of the vacuum plastic packaging bag; impurities in the evaporation boat and too fast aluminum feeding speed may cause uneven thickness distribution of aluminum molecules on the plastic film. This will cause irregular stripes or holes in the aluminum-plated film on the surface of the plastic packaging bag. In the optical density data series, this phenomenon is manifested as significant data fluctuations and obvious abnormal peaks.

[0049] Based on the above analysis, the optical density data sequence corresponding to any scan line on the surface of the plastic packaging bag to be detected is taken as an example for subsequent processing. The optical density data sequence is used as input, and the automatic multiscale-based peak detection (AMPD) algorithm is used to obtain all the peaks and troughs in the optical density data sequence, which are all recorded as peak data; all data except the peaks and troughs in the optical density data sequence are recorded as non-peak data. Since the AMPD multiscale peak detection algorithm is a well-known technology, the specific acquisition method will not be described in detail.

[0050] Among them, the peak value detection diagram of the local optical density value of the scanning line of the plastic packaging bag to be detected is as follows: Figure 2 shown. Figure 2The horizontal axis is the scanning point sequence, and the vertical axis is the optical density value.

[0051] For each scan line, the peak data volatility of each scan line is obtained according to the difference between each peak data and non-peak data, combined with the difference between each trough data and non-peak data: the sum of the absolute values ​​of the differences between each peak data and non-peak data is obtained, recorded as the first difference; the sum of the absolute values ​​of the differences between each trough data and the remaining non-peak data is obtained, recorded as the second difference; the first difference and the second difference are fused as the result of the peak data volatility of each scan line.

[0052] In this embodiment, the two variables are merged by adopting a multiplication calculation method, that is, the peak data volatility is specifically the product of the first difference and the second difference.

[0053] The greater the difference between all the peak data and non-peak data in the optical density sequence corresponding to the scanning line, and the greater the difference between all the trough data and non-peak data in the optical density sequence, the more significant the uneven thickness of the aluminum film on the surface of the plastic packaging bag is, the more obvious the fluctuation of the optical density data at the location where the aluminum film on the surface of the plastic packaging bag has irregular stripes or holes and other unfavorable conditions, and the stronger the volatility of the peak data.

[0054] During the vacuum aluminum plating process of plastic packaging bags, aluminum molecules may be deposited unevenly on the surface of the plastic film due to impurities in the evaporation boat or too fast aluminum feeding speed. At this time, if the location distribution of the uneven deposition is relatively concentrated, it usually leads to an increase in the discreteness between the optical density data on the scanning line, thus affecting the overall uniformity of the film. The uneven thickness of the film may lead to a reduction in its sealing and barrier properties, especially in areas where the thickness of the aluminum-plated film is thin or uneven.

[0055] Based on this, according to the distribution of all optical density data on each scanning line, combined with the distribution of the coordinates of the peak and trough positions, the optical density abnormality of each scanning line is obtained: the discrete degree of all optical density data on each scanning line is obtained, recorded as the first discrete degree; this embodiment uses the interquartile range to measure the discrete degree of optical density data; the chaos degree of the coordinates corresponding to all the peak and trough data on each scanning line is obtained, and this embodiment uses two-dimensional information entropy to measure the chaos degree of a group of data; based on the first discrete degree and the chaos degree, the optical density abnormality of each scanning line is obtained; wherein, the optical density abnormality is positively correlated with the discrete degree, and negatively correlated with the chaos degree.

[0056] It should be noted that a positive correlation indicates that as one variable increases, another variable also increases; a negative correlation indicates that as one variable increases, another variable decreases. In this embodiment, the ratio of the interquartile range to the two-dimensional information entropy is used as the degree of optical density abnormality of each scan line. In order to avoid the situation where the denominator is zero, a preset value needs to be added to the denominator. The preset value is 1, and the implementer can select it according to the actual situation.

[0057] When the aluminum film on the surface of the plastic packaging bag has an uneven deposition of aluminum molecules due to the presence of impurities in the evaporation boat or the aluminum feeding speed is too fast, the data distribution dispersion between the optical density data on the scanning line of the plastic film surface is more obvious, the distribution concentration of the fluctuation data of the optical density data on the plastic film surface is stronger, and the optical density anomaly is stronger, that is, the interquartile range of the optical density data sequence is larger, and the two-dimensional information entropy of all the peaks and troughs in the optical density data sequence corresponding to the position coordinates of the plastic packaging bag is smaller.

[0058] During the vacuum aluminum plating process of plastic packaging bags, the more obvious the fluctuation of the optical density peak data at different positions on the scanning line, the more significant the optical density abnormality. This indicates that due to impurities in the evaporation boat or too fast aluminum feeding speed, the more serious the unevenness of the aluminum molecule deposition thickness, the more uneven the aluminum plating film of the plastic packaging bag.

[0059] Therefore, based on the peak data fluctuation and the optical density abnormality of each scanning line, the thickness non-uniformity factor of each scanning line is obtained: the normalized value of the product of the peak data fluctuation and the optical density abnormality of each scanning line is taken as the thickness non-uniformity factor of each scanning line.

[0060] When there are impurities in the evaporation boat or the aluminum feeding speed is too fast, the deposition thickness of aluminum molecules on the plastic film surface will become uneven. This unevenness causes the peak value data fluctuation characteristics of the optical density data on the surface scanning line of the plastic packaging bag to be more obvious, the abnormality of the optical density data increases, and the thickness unevenness factor also increases accordingly.

[0061] The third sub-step: cluster all scan lines of each plastic packaging bag to be inspected based on the thickness unevenness factor, and obtain the aluminum plating unevenness factor of each plastic packaging bag to be inspected according to the difference in optical density data distribution in all pairwise clustering clusters in each plastic packaging bag to be inspected and the distance between cluster centers; take the preset time length as a vacuum aluminum plating interval, and obtain the aluminum plating film adjustment factor of each vacuum aluminum plating interval according to the distribution characteristics and change characteristics of all aluminum plating unevenness factors in each vacuum aluminum plating interval.

[0062] There are some shortcomings in evaluating the uniformity of aluminum molecule deposition on plastic packaging bags by relying solely on the thickness non-uniformity factor of each scanning line on the surface of the plastic film. First, this method lacks a comprehensive analysis of the uniformity of aluminum coating on the entire film surface. In addition, it does not take into account the deposition non-uniformity and its timing characteristics during the vacuum aluminum coating process, so it is impossible to accurately evaluate the uniformity of aluminum coating on plastic packaging bags. This limitation will affect the timely adjustment of aluminum coating parameters by relevant personnel, thereby affecting the sealing and barrier properties of plastic packaging bags.

[0063] The thickness unevenness factors corresponding to all scanning lines on any plastic packaging bag to be detected are taken as input, and the K-mediods clustering algorithm is used to obtain the clusters and cluster centers of the plastic packaging bags to be detected, where the number of clusters is set to 10, and the absolute value of the difference between the thickness unevenness factors corresponding to any two scanning lines is taken as the metric distance between the scanning lines.

[0064] The method can handle the correlation between the thickness non-uniformity of the aluminum-plated film at different positions on the surface of the plastic packaging bag, and accurately reflect the non-uniformity of the thickness of the aluminum-plated film at different positions caused by impurities in the evaporation boat or too fast aluminum feeding speed.

[0065] According to the difference in the distribution of optical density data in all pairwise combinations of clusters in each plastic packaging bag to be detected and the distance between the cluster centers, the aluminum plating uneven factor of each plastic packaging bag to be detected is obtained: the mean of all optical density data corresponding to all scanning lines in each cluster is obtained, and recorded as the optical density mean of each cluster; the difference between the optical density means of all pairwise combinations of clusters in each plastic packaging bag to be detected is fused to obtain a third difference; the parallel distances between the scanning lines corresponding to the cluster centers of all pairwise combinations of clusters in each plastic packaging bag to be detected are fused to obtain a parallel distance fusion result; the product of the third difference and the parallel distance fusion result is used as the aluminum plating uneven factor of each plastic packaging bag to be detected.

[0066] In this embodiment, when obtaining the aluminum plating non-uniformity factor, the difference between the optical density means is measured by the absolute value of the difference, and the difference between the optical density means and the parallel distance are fused in the form of accumulation.

[0067] In the process of vacuum aluminum plating of plastic packaging bags, if there are impurities in the evaporation boat or the aluminum feeding speed is too fast, the deposition non-uniformity of aluminum molecules on the plastic film will be aggravated, and the thickness difference of the aluminum film at different positions will be more obvious. Specifically, the greater the difference in the thickness of the aluminum film at the corresponding positions of each cluster in the film, the greater the distance between the scanning line areas where the thickness of the aluminum film on the film surface varies greatly. At the same time, the aluminum plating non-uniformity factor will increase, that is, in the plastic packaging bags to be tested, the cumulative result of the absolute value of the difference between the optical density means corresponding to all clusters will increase, and the cumulative result of the parallel distance between the corresponding scanning lines between the cluster centers of each cluster will also increase.

[0068] Generally speaking, if the uneven deposition of aluminum molecules on the surface of the film becomes more and more obvious over time during the vacuum aluminum plating process of plastic packaging bags, it usually means that the impurities in the evaporation boat increase, resulting in the aluminum molecules not being evenly evaporated and deposited on the surface of the plastic film during the evaporation process. This phenomenon will aggravate the uneven deposition of the aluminum film. Therefore, the aluminum plating process should be adjusted in time to prevent this uneven deposition from seriously affecting the sealing and barrier properties of the plastic packaging bags in subsequent use.

[0069] The preset time length is used as a vacuum aluminum plating interval. In this embodiment, the preset time length is 2 hours, and the implementer can set it according to the actual situation. Since a plastic packaging bag to be inspected has multiple scanning lines, one scanning line corresponds to one moment, so a plastic packaging bag to be inspected corresponds to multiple moments.

[0070] Obtain the discrete degree of the aluminum plating unevenness factor of all the plastic packaging bags to be tested corresponding to each vacuum aluminum plating interval, recorded as the second discrete degree; merge the differences in the aluminum plating unevenness factors of all adjacent plastic packaging bags to be tested in each vacuum aluminum plating interval to obtain a fourth difference; and use the normalized value of the product of the fourth difference and the second discrete degree as the aluminum plating film adjustment factor of each vacuum aluminum plating interval.

[0071] In this embodiment, the variance is used to measure the degree of dispersion of the aluminum-plating uneven factor; the difference is used to measure the difference in the aluminum-plating uneven factors of adjacent plastic packaging bags to be tested, and the aluminum-plating film adjustment factor of the qth vacuum aluminum-plating interval is recorded as , its formula form is: ;in, is the variance of the aluminum plating non-uniformity factor of all the plastic packaging bags to be tested corresponding to the qth vacuum aluminum plating interval; is the number of plastic packaging bags to be tested corresponding to the qth vacuum aluminum plating interval; is the difference in aluminum plating non-uniformity factor between the vth plastic packaging bag to be detected and the v-1th plastic packaging bag to be detected in the qth vacuum aluminum plating interval; norm[] is a normalization function, and in this embodiment, the normalization function is a sigmoid function, such that The value range of is between [0,1], exp() is an exponential function with the natural constant e as the base, and its purpose is to fully consider the positive difference between the aluminized film unevenness factor of the last plastic packaging bag and the aluminized film of the previous plastic packaging bag in the sampling sequence, that is, to consider the trend of increasing aluminized film unevenness on the surface of plastic packaging bags over time.

[0072] When the aluminized film non-uniformity of all the plastic packaging bags to be tested in the vacuum aluminized interval becomes more unstable, the aluminized film treatment of the plastic packaging bags needs more adjustments. As time goes by, the deposition non-uniformity of aluminum molecules on the surface of the plastic packaging bags will gradually increase, showing a more obvious trend of aluminized film non-uniformity. In this case, the aluminized adjustment factor of the vacuum aluminized interval increases, that is, the variance of the aluminized non-uniformity factor of all the plastic packaging bags to be tested in the vacuum aluminized interval will become larger; at the same time, the difference in aluminized film non-uniformity between each plastic packaging bag to be tested and the previous plastic packaging bag in the vacuum aluminized interval will become more significant.

[0073] The fourth sub-step: judging whether the aluminum coating process in the corresponding vacuum aluminum coating section is normal based on the aluminum coating adjustment factor.

[0074] When the aluminum film adjustment factor of the vacuum aluminum plating interval is less than the preset aluminum film adjustment threshold, it is determined that the aluminum film treatment in the vacuum aluminum plating interval is normal, and the uneven deposition on the surface of the plastic packaging bag caused by the presence of impurities in the evaporation boat or the excessive aluminum feeding speed is relatively minor, and there is no need to adjust the aluminum film treatment of the plastic packaging bag; when the aluminum film adjustment factor of the vacuum aluminum plating interval is greater than or equal to the preset aluminum film adjustment threshold, it is determined that the aluminum film treatment in the vacuum aluminum plating interval is abnormal, and the presence of impurities in the evaporation boat or the excessive aluminum feeding speed causes the uneven deposition of aluminum molecules on the surface of the plastic packaging bag. The vacuum aluminum plating of the plastic packaging bag needs to be stopped in time to avoid the waste of raw materials and the subsequent damage to the sealing and barrier properties of the plastic packaging bag. The implementer can use the above analysis for subsequent auxiliary decision-making, and timely adjust the current size of the evaporation boat, the aluminum feeding speed, or clean the evaporation boat to ensure the uniform deposition of aluminum molecules on the surface of the plastic film.

[0075] The aluminum film adjustment threshold value range is [0,1]. The larger the value, the stricter the aluminum film processing requirements for plastic packaging bags. In this embodiment, the aluminum film adjustment threshold value is 0.6. The implementer can set the aluminum film adjustment threshold value according to actual conditions.

[0076] Among them, the schematic diagram of the process of judging whether the aluminum coating treatment is normal is as follows Figure 3 shown.

[0077] According to another aspect of the present application, there is provided an aluminum film coating system for plastic packaging bags, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above methods when executing the computer program.

[0078] According to another aspect of the present application, there is provided an aluminized film coating device for plastic packaging bags, wherein a computer program is stored in the device, and when the computer program is executed by a processor, any one of the aluminized film coating methods described above is implemented.

[0079] In summary, the embodiment of the present application obtains the thickness non-uniformity factor through the optical density data fluctuation status and data abnormality characteristics corresponding to the scanning line of the plastic packaging bag, comprehensively considers the optical density peak data fluctuation characteristics and optical density abnormality characteristics of each scanning line area on the surface of the plastic packaging bag, and more accurately reflects the uneven thickness of aluminum molecule deposition on the surface of the plastic packaging bag corresponding to the scanning line area; based on the thickness non-uniformity factor, all scanning lines of each plastic packaging bag to be detected are clustered, and the aluminum-plated film adjustment factor is obtained through the uneven thickness characteristics of the aluminum-plated film between the clusters and the uneven aluminum-plating time series characteristics, and the vacuum aluminum-plating treatment of the plastic packaging bag is judged based on this, and on the basis of considering the uneven aluminum-plating condition of the entire plastic packaging bag, the trend of the uneven aluminum-plating condition within the time series interval is considered, which more accurately reflects the uniformity of aluminum molecule deposition on the surface of the plastic packaging bag, improves the accuracy of the judgment result, and provides scientific data support for subsequent auxiliary relevant personnel to timely adjust the aluminum-plating film processing process of the plastic packaging bag, avoiding the disadvantage that the sealing and barrier properties are damaged due to the uneven aluminum-plating film of the plastic packaging bag.

[0080] It should be noted that the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the system, method and computer program product according to the embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in an order different from that disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

[0081] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for aluminizing a plastic packaging bag, characterized in that: The method comprises the following steps: Use inert gas to perform glow cleaning on plastic packaging bag films; Under vacuum environment, set the temperature parameters and speed parameters of the machine when aluminizing plastic packaging bags, aluminize the plastic packaging bags and determine whether the aluminizing process is normal; The process of judging whether the aluminum coating process is normal is as follows: Obtain the optical density data of each plastic packaging bag to be inspected on each scanning line at each moment; Perform peak detection on all optical density data on each scan line. For each scan line, the difference between the peak data and the non-peak data is combined with the distribution of all optical density data on each scan line and the distribution of the peak data coordinates to obtain the thickness non-uniformity factor of each scan line. Cluster all scan lines of each plastic packaging bag to be inspected based on the thickness non-uniformity factor, and obtain the aluminum plating non-uniformity factor of each plastic packaging bag to be inspected according to the difference in the distribution of optical density data in all the clustering clusters of each pairwise combination of the plastic packaging bag to be inspected and the distance of the cluster center; take the preset time length as a vacuum aluminum plating interval, and obtain the aluminum plating film adjustment factor of each vacuum aluminum plating interval according to the distribution characteristics and change characteristics of all aluminum plating non-uniformity factors in each vacuum aluminum plating interval; Based on the aluminum coating adjustment factor, judging whether the aluminum coating process in the corresponding vacuum aluminum coating section is normal; The thickness non-uniformity factor of each scanning line is obtained as follows: For each scan line, the peak data volatility of each scan line is obtained according to the difference between each peak data and non-peak data, combined with the difference between each trough data and non-peak data; Obtain the degree of dispersion of all optical density data on each scanning line, recorded as the first dispersion degree; obtain the degree of disorder of coordinates corresponding to all peak and trough data on each scanning line; based on the first dispersion degree and the disorder degree, obtain the degree of optical density abnormality of each scanning line; wherein the degree of optical density abnormality is positively correlated with the dispersion degree and negatively correlated with the disorder degree; The normalized value of the product of the peak data fluctuation of each scanning line and the optical density abnormality is used as the thickness non-uniformity factor of each scanning line; The peak value data fluctuation of each scan line is obtained as follows: Obtain the sum of the absolute values ​​of the differences between each peak data and the non-peak data, recorded as the first difference; obtain the sum of the absolute values ​​of the differences between each trough data and the remaining non-peak data, recorded as the second difference; fuse the first difference and the second difference to obtain the peak data volatility of each scan line; The process of obtaining the aluminum plating non-uniformity factor of each plastic packaging bag to be tested includes: Obtain the mean of all optical density data corresponding to all scanning lines in each cluster, and record it as the optical density mean of each cluster; fuse the differences between the optical density means of all clusters in pairs in each plastic packaging bag to be detected to obtain a third difference; fuse the parallel distances between the scanning lines corresponding to the cluster centers of all clusters in pairs in each plastic packaging bag to be detected to obtain a parallel distance fusion result; and use the product of the third difference and the parallel distance fusion result as the aluminum plating unevenness factor of each plastic packaging bag to be detected; The step of obtaining the aluminum coating adjustment factor of each vacuum aluminum coating interval includes: Obtain the discrete degree of the aluminum plating unevenness factor of all the plastic packaging bags to be tested corresponding to each vacuum aluminum plating interval, recorded as the second discrete degree; merge the differences in the aluminum plating unevenness factors of all adjacent plastic packaging bags to be tested in each vacuum aluminum plating interval to obtain a fourth difference; and use the normalized value of the product of the fourth difference and the second discrete degree as the aluminum plating film adjustment factor of each vacuum aluminum plating interval.

2. A method for aluminizing a plastic packaging bag as claimed in claim 1, characterized in that: The glow cleaning process lasts for 5 to 10 minutes.

3. A method for aluminizing a plastic packaging bag as claimed in claim 1, characterized in that: The temperature parameters and speed parameters of the machine when setting the aluminum film of the plastic packaging bag are specifically: When the plastic packaging bag is aluminized, the temperature of the coating drum is set to 0~2°C, the temperature of the evaporation boat is set to 1200~1400°C, the wire feeding speed of the aluminum wire is set to 220~260mm / min, and the winding speed of the coating is set to 5~10m / s.

4. A method for aluminizing a plastic packaging bag as claimed in claim 1, characterized in that: The determination of whether the aluminum coating process in the corresponding vacuum aluminum coating section is normal is specifically as follows: When the aluminum coating adjustment factor of the vacuum aluminum coating section is less than the preset aluminum coating adjustment threshold, it is determined that the aluminum coating process of the vacuum aluminum coating section is normal; otherwise, it is determined that the aluminum coating process of the vacuum aluminum coating section is abnormal.

5. A system for coating an aluminum film on a plastic packaging bag, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 4 are implemented.

6. A device for aluminizing plastic packaging bags, wherein a computer program is stored in the device, characterized in that: When the computer program is executed by a processor, the aluminum film coating method according to any one of claims 1 to 4 is implemented.

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