A process for preparing water-based printing layer raw material for thermal transfer receiving sheet

Abstract

The present application relates to the field of polymerization technology, and specifically to a process for preparing a water-based printing layer raw material for a thermal transfer receiving sheet, the process comprising: preparing a heterogeneous system: adding material A, material B and material C to a reaction container, and obtaining a heterogeneous system by stirring; polymerization reaction: mixing the heterogeneous system with a solution containing ferric chloride and isopropanol, causing a polymerization reaction, and regulating the polymerization temperature in the reaction container according to the change of polymerization temperature data at different positions during the polymerization reaction, and preparing a vinyl chloride resin composite: adding water to terminate the reaction after reaching the set polymerization reaction time, washing the reaction system with water and hexane in turn, repeating for multiple times, and obtaining a vinyl chloride resin composite by vacuum drying. The present application can accurately reflect the temperature deviation of the polymerization reaction, improve the control accuracy of the polymerization temperature in the preparation process of the vinyl chloride resin composite using a PID controller, and thus improve the quality of raw material preparation.

Description

Technical Field

[0001] The present application relates to the technical field of polymerization technology, and in particular to a process for preparing a water-based printing layer raw material for a thermal transfer receiving sheet. Background Art

[0002] In recent years, the sublimation transfer recording method of forming an image on a transfer layer receiving sheet by heating a ribbon containing a sublimation dye by using a heating medium such as a heating print head or a laser has received widespread attention, and thermal sublimation printing technology has been used as an information recording unit in various fields. According to such a thermal sublimation printing method, a full-color gradation image can be formed in a very short time, and intermediate colors and full colors with excellent reproducibility and grayscale can be obtained, forming a high-quality image equivalent to a silver halide photograph; wherein the structural composition of the thermal transfer receiving sheet includes a printing layer, a heat insulating layer, a substrate and a back coating layer, and the printing layer is a necessary structure of the thermal transfer receiving sheet, and an image is formed on the printing layer by thermal sublimation of a thermal sublimation ribbon having a dye layer, so that a raw material that easily accepts sublimation dyes can be used to improve the quality of the image generated by the thermal transfer receiving sheet.

[0003] The existing raw materials commonly used for the printing layer mainly include polypropylene resin, polyvinyl acetate, polyethylene terephthalate, polyester resin and vinyl chloride resin, etc. The more preferred materials are vinyl chloride resins, etc. Among them, although vinyl chloride resins have good transfer effects on thermal transfer receiving sheets, vinyl chloride still has problems such as poor thermal stability, poor toughness, and low impact strength. Through various existing preparation processes, the vinyl chloride resin composites are improved, and the stability, impact strength and other performance of the vinyl chloride resin composites are improved. However, the traditional automatic control accuracy of the polymerization temperature in the preparation process of the vinyl chloride resin composites is still low, which in turn affects the performance of the prepared vinyl chloride resin composite materials and the transfer effect of the thermal transfer receiving sheet. Summary of the invention

[0004] In order to solve the above technical problems, the present application provides a process for preparing a water-based printing layer raw material for a thermal transfer receiving sheet to solve the existing problems.

[0005] The present invention discloses a process for preparing a water-based printing layer raw material for a thermal transfer receiving sheet using the following technical solutions:

[0006] One embodiment of the present application provides a process for preparing a water-based printing layer material for a thermal transfer receiving sheet, the method comprising the following steps:

[0007] Preparation of a heterogeneous system: adding material A, material B and material C into a reaction container, and stirring to obtain a heterogeneous system;

[0008] Polymerization reaction: The heterogeneous system is mixed with a solution containing ferric chloride and isopropanol to cause a polymerization reaction. The polymerization temperature is regulated during the polymerization reaction. The specific regulation process is as follows:

[0009] The polymerization temperature data in the polymerization reaction process is collected by multiple temperature sensors, and the dynamic significant coefficient of the printing material preparation at each collection moment is determined based on the dynamic change of the polymerization temperature data;

[0010] Based on the maximum value of the dynamic significant coefficient of the printing material preparation at all acquisition moments, and in combination with the fluctuation characteristics of the polymerization temperature acquired by each temperature sensor, a preparation local dynamic fluctuation sensitivity index is determined;

[0011] Based on the preparation local dynamic fluctuation sensitivity index, the printing material preparation fluctuation contrast coefficient is determined, and then the polymerization temperature is regulated in combination with the PID controller;

[0012] Preparation of vinyl chloride resin composite: After reaching the set polymerization reaction time, water is added to terminate the reaction, and the reaction system is washed with water and hexane in sequence, and the process is repeated for multiple times, and the vinyl chloride resin composite is obtained by vacuum drying.

[0013] In some embodiments, the mass ratio of material A, material B and material C is 3:8:8.

[0014] In some embodiments, the material A is solid polyvinyl chloride, wherein the polymer has a weight average molecular weight of 80 to 300 kg / mol, a molecular weight distribution index of 1.6 to 3, and a particle size of 50 to 150 μm.

[0015] In some embodiments, the material B is an isobutylene solution, and the material C is obtained by mixing sodium chloride, potassium chloride, lithium chloride and water in a mass ratio of 1:1:22:76.

[0016] In some embodiments, the molar ratio of polyvinyl chloride, ferric chloride, isopropanol and isobutylene during the polymerization reaction is 4×10 -3 :6.5×10 -2 : 6×10 -2 :1.

[0017] In some embodiments, the determination process of the dynamic significant coefficient of the printing material preparation at each acquisition moment is as follows:

[0018] The aggregated temperature data of all temperature sensors at each acquisition moment are combined into an instantaneous characteristic sequence of substrate preparation at each acquisition moment, a first-order difference sequence corresponding to the instantaneous characteristic sequence of substrate preparation is obtained, and the mean of the first-order difference sequence is used as the confidence coefficient of the substrate preparation characteristic at each acquisition moment;

[0019] Analyze the distance between the printing preparation instantaneous feature sequence at each acquisition moment and other acquisition moments, and record it as the instantaneous distance at each acquisition moment; analyze the difference between the printing preparation feature confidence coefficient at each acquisition moment and other acquisition moments, and record it as the confidence difference at each acquisition moment;

[0020] The dynamic significance coefficient of the printing material preparation at each acquisition moment is positively correlated with all the instantaneous distances at each acquisition moment, and is negatively correlated with all the confidence differences analyzed at each acquisition moment.

[0021] In some embodiments, the determination process of preparing the local dynamic fluctuation sensitivity index is:

[0022] The aggregated temperature data of each temperature sensor at all acquisition moments are combined into a substrate preparation feature analysis sequence for each temperature sensor;

[0023] The times corresponding to the minimum and maximum values ​​of the dynamic significant coefficients of the printing material preparation at all the acquisition times are counted respectively, recorded as the minimum significant time and the maximum significant time, and the time interval formed by the minimum significant time and the maximum significant time is used as the relative local dynamic analysis time interval;

[0024] The variance of all polymerization temperature data of the substrate preparation characteristic analysis sequence of each temperature sensor in the relatively local dynamic analysis time interval is used as the first analysis characteristic value of each temperature sensor, and the mean of the dynamic significant coefficients of the substrate preparation at all acquisition moments is used as the second analysis characteristic value;

[0025] According to the first analysis characteristic value and the second analysis characteristic value of each temperature sensor, the preparation local dynamic fluctuation sensitivity index of each temperature sensor is obtained, wherein the preparation local dynamic fluctuation sensitivity index is positively correlated with the first analysis characteristic value and the second analysis characteristic value of each temperature sensor, respectively.

[0026] In some embodiments, determining the printing material preparation fluctuation contrast coefficient and then regulating the polymerization temperature in combination with a PID controller specifically includes:

[0027] The proportion of the preparation local dynamic fluctuation sensitivity index of each temperature sensor in the preparation local dynamic fluctuation sensitivity index of all temperature sensors is used as the printing material preparation fluctuation contrast coefficient of each temperature sensor;

[0028] Analyze the difference between the polymerization temperature data collected by each temperature sensor at the current collection moment and the preset polymerization reaction temperature, and multiply the difference by the printing material preparation fluctuation contrast coefficient of each temperature sensor as the first difference parameter of each temperature sensor;

[0029] The average value of the first difference parameters of all temperature sensors is used as the input of the PID controller to obtain the output value of the polymerization temperature control in the reaction container.

[0030] In some embodiments, the vinyl chloride resin composite includes polyvinyl chloride particles and a polyvinyl chloride graft copolymer coated on the surface of the polyvinyl chloride particles.

[0031] In some embodiments, the polyvinyl chloride graft copolymer is a polymer in which a polyvinyl chloride main chain is connected to a plurality of isobutylene-based polymer chain segments, wherein the total mass content of the isobutylene-based polymer chain segment segments is 15 wt %.

[0032] This application has at least the following beneficial effects:

[0033] The present application achieves this by uniformly dispersing vinyl chloride resin and isobutylene-based polymer chain segments in two phases during the preparation of a vinyl chloride resin composite material, and using a plurality of temperature sensors to collect polymerization temperature data in the automatic control of the polymerization temperature in a reaction container during the preparation process, and by integrating the analysis results of the local dynamic relative change relationship of the polymerization temperature of a plurality of temperature sensors at different collection moments and combining with a PID controller to accurately control the polymerization temperature. The beneficial effect of the present application is that the influence of the process preparation environment on the collected data during the polymerization reaction is considered, and the deviation results of the polymerization temperatures of different temperature sensors are integrated by dividing the time intervals through the comprehensive state comparison of a plurality of temperature sensors, so as to accurately reflect the temperature deviation of the polymerization reaction, thereby improving the control accuracy of the polymerization temperature in the preparation of the vinyl chloride resin composite using the PID controller, and improving the quality of the prepared vinyl chloride resin composite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A flow chart of the steps of a process for preparing a water-based printing layer material for a thermal transfer receiving sheet provided in the present application;

[0036] Figure 2 It is a schematic diagram of the temperature regulation process during the polymerization reaction;

[0037] Figure 3 Schematic diagram of the preparation process of aqueous printing layer raw materials for thermal transfer receiving sheets. DETAILED DESCRIPTION

[0038] In order to further explain the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the following is a detailed description of a water-based printing layer raw material preparation process for a thermal transfer receiving sheet proposed by the present application, its specific implementation method, structure, characteristics and effects, in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0039] Unless otherwise defined, terms such as "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a circuit structure, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such articles or devices. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the article or device comprising the element. In addition, the term "and\or" used herein includes any and all combinations of one or more related listed items. All technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present application belongs.

[0040] The specific scheme of the process for preparing a water-based printing layer raw material for a thermal transfer receiving sheet provided by the present application is described in detail below in conjunction with the accompanying drawings.

[0041] An embodiment of the present application provides a process for preparing a water-based printing layer material for a thermal transfer receiving sheet. Specifically, the following process for preparing a water-based printing layer material for a thermal transfer receiving sheet is provided. Figure 1 , the process comprises the following steps:

[0042] S1, preparing a heterogeneous system: adding material A, material B and material C in a mass ratio of 3:8:8 into a reaction container, wherein material A is solid polyvinyl chloride (wherein the polymer weight average molecular weight is 80-300 kg / mol, the molecular weight distribution index is 1.6-3, and the particle size is 50-150 μm); material B is a precooled isobutylene solution; material C is an aqueous phase medium (a mixed solution of sodium chloride, potassium chloride, lithium chloride and water in a mass ratio of 1:1:22:76), and stirring the materials added to the reactor to obtain a heterogeneous system; wherein the reaction container is a polymerization kettle.

[0043] S2, polymerization reaction: the obtained heterogeneous system is mixed with a solution containing ferric chloride and isopropanol, wherein the molar ratio of polyvinyl chloride, ferric chloride, isopropanol and isobutylene is 4×10 -3 :6.5×10 -2 : 6×10-2 :1; The polymerization reaction temperature in the reaction container is preset to be -75°C, and the polymerization reaction time is 5 minutes. After the polymerization reaction time is reached, 50 ml of water is added to the reaction container to terminate the reaction. During the polymerization reaction, the polymerization temperature is controlled according to the set temperature through the temperature data collected in the reaction container during the reaction process. The control range of the polymerization temperature is -85 to 5°C. For details, please refer to the schematic diagram of the temperature regulation process during the polymerization reaction. Figure 2 The specific adjustment process is as follows:

[0044] Step 1: Obtain polymerization temperature data in a reaction vessel during the preparation of vinyl chloride composite materials.

[0045] α temperature sensors are evenly arranged in the reaction container, and the value of α in the embodiment is 6. It should be noted that the temperature sensor used is a low-temperature resistant probe temperature sensor. The specific model of the temperature sensor can be selected by the implementer according to the actual application scenario. After the polymerization reaction in the reaction container starts, the temperature data in the reaction container is collected by the temperature sensor at a time interval of 0.1s.

[0046] At this point, the polymerization temperature data in the reaction vessel has been acquired.

[0047] Step 2: According to the local state difference of the polymerization temperature data in the reaction container during the preparation of the vinyl chloride composite material, a dynamic significance coefficient of the printing raw material preparation is constructed; according to the dynamic significance coefficient of the printing raw material preparation, a local dynamic fluctuation sensitivity index is constructed; based on the local dynamic sensitivity fluctuation index, the fluctuation comparison coefficient of the printing raw material preparation is obtained.

[0048] In the preparation process of vinyl chloride composite materials, the most important controllable factor affecting the polymerization reaction is the polymerization temperature in the reaction vessel. Furthermore, the polymerization temperature is the main factor affecting the degree of polymerization, which directly affects the quality of the prepared vinyl chloride composite materials. In the preparation process, the uneven mixing of materials in the reaction vessel during the polymerization reaction will result in uneven heat distribution, that is, the local differences in the polymerization reaction temperatures of the mixed materials at different positions are large, resulting in uneven polymerization temperature changes. The polymerization reaction temperature is required to be strictly controlled during the polymerization reaction. The temperature of the polymerization reaction of the materials in the reaction vessel fluctuates within a small range. However, the uneven heat distribution during the polymerization reaction will cause the polymerization temperature data collected at different positions for monitoring to present a large difference in fluctuation characteristics. The fluctuation deviation analyzed by the collected polymerization temperature data is greatly deviated from the overall polymerization temperature of the polymerization reaction of the materials in the actual reaction vessel. Therefore, in the process of using the traditional control method to control the temperature in the reaction vessel, due to the influence of the system parameters and the polymerization reaction characteristics of the materials in the reaction vessel on the collected polymerization temperature data at different time points, the control accuracy of the polymerization temperature is low, resulting in poor quality of the materials obtained by the polymerization reaction of the materials in the reaction vessel.

[0049] Furthermore, the polymerization temperature data in the reaction vessel of the vinyl chloride composite material preparation process is obtained by step 1, and the sequence of the polymerization temperature data collected by each temperature sensor in the reaction vessel in ascending time order is used as a substrate preparation feature analysis sequence, and the substrate preparation feature analysis sequence of each temperature sensor can be obtained. At the same time, the polymerization temperature data collected by all temperature sensors at the same collection time is obtained, that is, the polymerization temperature state in the reaction vessel at the same collection time is reflected through the comprehensive characteristics of multiple position data, so the local state difference of the polymerization temperature data in the reaction vessel can be analyzed through the polymerization temperature state difference between different collection times.

[0050] Specifically, the aggregated temperature data collected by all temperature sensors at each collection moment constitutes an instantaneous characteristic sequence of substrate preparation at each collection moment, and the dynamic significant coefficient of substrate preparation at each collection moment is obtained through the dynamic change difference of the instantaneous characteristic sequence of substrate preparation at different collection moments, wherein the process of obtaining the dynamic significant coefficient of substrate preparation includes:

[0051] Obtaining a first-order difference sequence of the instantaneous feature sequence of the printing preparation at each acquisition moment, and taking the mean of all elements in the first-order difference sequence as the confidence coefficient of the printing preparation feature at each acquisition moment;

[0052] Analyze the distance between the printing preparation instantaneous feature sequence at each acquisition moment and other acquisition moments, and record it as the instantaneous distance at each acquisition moment; analyze the difference between the printing preparation feature confidence coefficient at each acquisition moment and other acquisition moments, and record it as the confidence difference at each acquisition moment;

[0053] The dynamic significance coefficient of the printing material preparation at each acquisition moment is positively correlated with all the instantaneous distances at each acquisition moment, and is negatively correlated with all the confidence differences analyzed at each acquisition moment.

[0054] It should be noted that the positive correlation is used to characterize that the changing trends between variables are the same. The dependent variable increases with the increase of the independent variable, and decreases with the decrease of the independent variable. It can be limited by positive correlation relationships such as addition and multiplication, which depends on the actual application scenario. This application does not impose any special restrictions on this. Correspondingly, the negative correlation is used to characterize that the changing trends between variables are opposite. The dependent variable decreases with the increase of the independent variable, and increases with the decrease of the independent variable. It can be limited by negative correlation relationships such as inverse proportional relationships, which depends on the actual application scenario.

[0055] Preferably, in this embodiment, for the instantaneous feature sequence of substrate preparation at each collection moment, the Manhattan distance between the instantaneous feature sequence of substrate preparation at each collection moment and the instantaneous feature sequence of substrate preparation at each other collection moment is used as the numerator, and the larger the numerator, the greater the difference in polymerization temperature state characteristics of the data collected at different collection moments; the absolute value of the difference between the confidence coefficient of the substrate preparation feature at each collection moment and each other collection moment is taken, and the absolute value is used as the exponent of an exponential function with a natural constant as the base, and the exponential function is used as the denominator, and the smaller the denominator, the closer the confidence level of the polymerization temperature data collected at different positions at each collection moment is; the average of the cumulative results of the ratio of the numerator to the denominator at each collection moment and all other collection moments is used as the dynamic significance coefficient of substrate material preparation at each collection moment, and the relative degree of change of the local state at each collection moment is reflected by the dynamic significance coefficient of substrate material preparation.

[0056] Furthermore, the local dynamic fluctuation sensitivity index is calculated by preparing the dynamic significant coefficient of the printing material corresponding to all the acquisition moments, and the sensitive change characteristics of the local state of the polymerization temperature data in the polymerization reaction process in the reaction container are analyzed by preparing the local dynamic fluctuation sensitivity index. The specific process of obtaining the preparation of the local dynamic fluctuation sensitivity index includes:

[0057] The times corresponding to the minimum and maximum values ​​of the dynamic significant coefficients of the printing material preparation at all the acquisition moments are counted respectively, and recorded as the minimum significant moment and the maximum significant moment respectively, and the time interval formed by the minimum significant moment and the maximum significant moment is used as the relative local dynamic analysis time interval;

[0058] The variance of all polymerization temperature data of the substrate preparation characteristic analysis sequence of each temperature sensor in the relatively local dynamic analysis time interval is used as the first analysis characteristic value of each temperature sensor, and the mean of the dynamic significant coefficients of the substrate preparation at all acquisition moments is used as the second analysis characteristic value;

[0059] Based on the first analysis characteristic value and the second analysis characteristic value of each temperature sensor, the preparation local dynamic fluctuation sensitivity index of each temperature sensor is determined, wherein the preparation local dynamic fluctuation sensitivity index is positively correlated with the first analysis characteristic value and the second analysis characteristic value of each temperature sensor, respectively.

[0060] Preferably, in this embodiment, the product of the first analysis characteristic value and the second analysis characteristic value of each temperature sensor is used as the preparation local dynamic fluctuation sensitivity index of each temperature sensor.

[0061] It should be understood that a larger preparation local dynamic fluctuation sensitivity index indicates that the printing preparation feature analysis sequence corresponding to each temperature sensor has significant local dynamic relative change characteristics in the relative local dynamic analysis time interval, that is, it characterizes the degree to which the polymerization temperature data collected by each temperature sensor is affected by local sensitive fluctuations.

[0062] Furthermore, the proportion of the preparation local dynamic fluctuation sensitivity index of each temperature sensor in the preparation local dynamic fluctuation sensitivity index of all temperature sensors is used as the printing material preparation fluctuation contrast coefficient corresponding to each temperature sensor. The printing material preparation fluctuation contrast coefficient reflects the relative confidence level of the polymerization temperature data at different positions in the reaction container.

[0063] At this point, the printing material preparation fluctuation contrast coefficient is obtained.

[0064] Step 3: According to the fluctuation contrast coefficient of the printing material preparation, the polymerization temperature is precisely controlled by combining the PID controller.

[0065] The above step 2 obtains the printing material preparation fluctuation contrast coefficient corresponding to each temperature sensor during the polymerization reaction. Further, the difference between the polymerization temperature data collected by each temperature sensor at the current collection time of the reaction container and the preset polymerization reaction temperature is calculated, and the product of the difference and the printing material preparation fluctuation contrast coefficient of the corresponding temperature sensor is used as the first difference parameter of each temperature sensor. Furthermore, the average value of the first difference parameters of all temperature sensors is used as the input of the PID controller to obtain the output value of the polymerization temperature control in the reaction container.

[0066] It should be noted that the traditional control process is to use the difference between the temperature data actually collected by the temperature sensor and the standard temperature as input to obtain the output value of the polymerization temperature, but this method is easily affected by the uneven heat distribution during the polymerization process. Therefore, by setting multiple temperature sensors and analyzing the comparative analysis results of different temperature sensors, the actual temperature data collected by multiple temperature sensors and the standard temperature difference are combined and fused to obtain the first difference parameter. The first difference parameter can accurately reflect the difference between the actual temperature data and the standard temperature, and then precise control can be performed.

[0067] The proportional gain, integral gain and differential gain of the PID controller can be obtained by the attenuation curve method. The specific process of adjusting the PID controller parameters by the attenuation curve method is a technology well known to those skilled in the art, and the specific process will not be repeated here. The PID controller obtains an accurate output value of the polymerization temperature control in the reaction container by taking the mean of the first difference parameters of all temperature sensors in the reaction container at the current moment as the difference between the actual polymerization temperature and the standard polymerization temperature.

[0068] S3, preparing a vinyl chloride resin composite: after the polymerization reaction is completed, 50 ml of water is added to the reaction container to terminate the reaction, and the reaction system obtained after the termination of the reaction is washed with water and hexane in sequence, and the process is repeated multiple times. In this embodiment, the process is repeated three times to obtain an undried vinyl chloride resin composite, and the undried vinyl chloride resin composite is vacuum dried at 40° C. to obtain a dried vinyl chloride resin composite.

[0069] The vinyl chloride resin composite comprises polyvinyl chloride particles and a polyvinyl chloride graft copolymer coated on the surface of the polyvinyl chloride particles, wherein the polyvinyl chloride graft copolymer is a polymer in which a polyvinyl chloride main chain is connected to a plurality of isobutylene polymer chain segments, and the total mass content of the isobutylene polymer chain segment segments is 15wt%.

[0070] For a specific schematic diagram of the preparation process of the aqueous printing layer material for the thermal transfer receiving sheet, please refer to Figure 3 .

[0071] It is understood that references to "one embodiment" or "some embodiments" etc. described in the specification of the present application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, if "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. appear in different places in this specification, they do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0072] It should be noted that the sequence of the above-mentioned embodiments of the present application is only for description and does not represent the advantages and disadvantages of the embodiments. And the above-mentioned specific embodiments of this specification are described. In addition, the process depicted in the accompanying drawings does not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multi-tasking and parallel processing are also possible or may be advantageous. At the same time, the size of the sequence number of each step in the embodiment does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments in this specification.

[0073] 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 process for preparing a water-based printing layer material for a thermal transfer receiving sheet, characterized in that: The process includes the following steps: Preparation of a heterogeneous system: adding material A, material B and material C into a reaction container, and stirring to obtain a heterogeneous system; Polymerization reaction: The heterogeneous system is mixed with a solution containing ferric chloride and isopropanol to cause a polymerization reaction. The polymerization temperature is regulated during the polymerization reaction. The specific regulation process is as follows: The polymerization temperature data in the polymerization reaction process is collected by multiple temperature sensors, and the dynamic significant coefficient of the printing material preparation at each collection moment is determined based on the dynamic change of the polymerization temperature data; Based on the maximum value of the dynamic significant coefficient of the printing material preparation at all acquisition moments, and in combination with the fluctuation characteristics of the polymerization temperature acquired by each temperature sensor, a preparation local dynamic fluctuation sensitivity index is determined; Based on the preparation local dynamic fluctuation sensitivity index, the printing material preparation fluctuation contrast coefficient is determined, and then the polymerization temperature is regulated in combination with the PID controller; Preparation of vinyl chloride resin composite: after reaching the set polymerization reaction time, water is added to terminate the reaction, the reaction system is washed with water and hexane in sequence, the process is repeated for multiple times, and the vinyl chloride resin composite is obtained by vacuum drying; The material A is solid polyvinyl chloride, wherein the polymer weight average molecular weight is 80 to 300 kg / mol, the molecular weight distribution index is 1.6 to 3, and the particle size is 50 to 150 μm; The material B is an isobutylene solution, and the material C is obtained by mixing sodium chloride, potassium chloride, lithium chloride and water in a mass ratio of 1:1:22:76; The determination process of the dynamic significant coefficient of the printing material preparation at each acquisition moment is as follows: The aggregated temperature data of all temperature sensors at each acquisition moment are combined into an instantaneous characteristic sequence of substrate preparation at each acquisition moment, a first-order difference sequence corresponding to the instantaneous characteristic sequence of substrate preparation is obtained, and the mean of the first-order difference sequence is used as the confidence coefficient of the substrate preparation characteristic at each acquisition moment; Analyze the distance between the printing preparation instantaneous feature sequence at each acquisition moment and other acquisition moments, and record it as the instantaneous distance at each acquisition moment; analyze the difference between the printing preparation feature confidence coefficient at each acquisition moment and other acquisition moments, and record it as the confidence difference at each acquisition moment; The dynamic significant coefficient of the printing material preparation at each acquisition moment is positively correlated with all the instantaneous distances at each acquisition moment, and negatively correlated with all the confidence differences analyzed at each acquisition moment; The determination process of preparing the local dynamic fluctuation sensitivity index is as follows: The aggregated temperature data of each temperature sensor at all acquisition moments are combined into a substrate preparation feature analysis sequence for each temperature sensor; The times corresponding to the minimum and maximum values ​​of the dynamic significant coefficients of the printing material preparation at all the acquisition times are counted respectively, recorded as the minimum significant time and the maximum significant time, and the time interval formed by the minimum significant time and the maximum significant time is used as the relative local dynamic analysis time interval; The variance of all polymerization temperature data of the substrate preparation characteristic analysis sequence of each temperature sensor in the relatively local dynamic analysis time interval is used as the first analysis characteristic value of each temperature sensor, and the mean of the dynamic significant coefficients of the substrate preparation at all acquisition moments is used as the second analysis characteristic value; According to the first analysis characteristic value and the second analysis characteristic value of each temperature sensor, a preparation local dynamic fluctuation sensitivity index of each temperature sensor is obtained, wherein the preparation local dynamic fluctuation sensitivity index is positively correlated with the first analysis characteristic value and the second analysis characteristic value of each temperature sensor, respectively; The step of determining the printing material preparation fluctuation contrast coefficient and then regulating the polymerization temperature in combination with a PID controller specifically includes: The proportion of the preparation local dynamic fluctuation sensitivity index of each temperature sensor in the preparation local dynamic fluctuation sensitivity index of all temperature sensors is used as the printing material preparation fluctuation contrast coefficient of each temperature sensor; Analyze the difference between the polymerization temperature data collected by each temperature sensor at the current collection moment and the preset polymerization reaction temperature, and multiply the difference by the printing material preparation fluctuation contrast coefficient of each temperature sensor as the first difference parameter of each temperature sensor; The average value of the first difference parameters of all temperature sensors is used as the input of the PID controller to obtain the output value of the polymerization temperature control in the reaction container.

2. A process for preparing a water-based printing layer material for a thermal transfer receiving sheet as claimed in claim 1, characterized in that: The mass ratio of material A, material B and material C is 3:8:

8.

3. A process for preparing a water-based printing layer material for a thermal transfer receiving sheet as claimed in claim 1, characterized in that: The molar ratio of polyvinyl chloride, ferric chloride, isopropanol and isobutylene during the polymerization reaction is 4×10 -3 :6.5×10 -2 : 6×10 -2 :

1.

4. A process for preparing a water-based printing layer material for a thermal transfer receiving sheet as claimed in claim 1, characterized in that: The vinyl chloride resin compound comprises polyvinyl chloride particles and a polyvinyl chloride graft copolymer coated on the surface of the polyvinyl chloride particles.

5. A process for preparing a water-based printing layer material for a thermal transfer receiving sheet as claimed in claim 4, characterized in that: The polyvinyl chloride graft copolymer is a polymer in which a polyvinyl chloride main chain is connected to a plurality of isobutylene polymer chain segments, wherein the total mass content of the isobutylene polymer chain segment segments is 15wt%.

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