A method for testing the paint redispersibility

Abstract

The present application relates to the technical field of paint detection, and particularly relates to a paint redispersion performance test method. The method comprises the following steps: centrifuging paint of a preset volume loaded in a centrifuge cylinder; obtaining the thickness of the hard bottom of the initial paint; adjusting the centrifugation parameters based on the thickness of the hard bottom, or generating test paint by performing vibration treatment; pouring out the test paint and taking out the magnetic vibration block, obtaining the area proportion of the hard block by image scanning, and generating a dispersion representation coefficient based on the area proportion of the hard block and the vibration frequency; when the paint redispersion does not meet the preset standard based on the dispersion representation coefficient, increasing the vibration time, or collecting the image of the remaining hard bottom at the bottom of the centrifuge cylinder to calculate the hard bottom damage value; and determining that the reason why the paint redispersion does not meet the preset standard based on the hard bottom damage value includes insufficient dispersant and collapse of the additive system. The present application effectively detects whether the paint redispersion meets the preset standard, and improves the accuracy of the paint redispersion performance test.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of paint detection, in particular to a paint redispersion performance test method. BACKGROUND

[0002] The paint redispersion performance test is crucial for the quality control and actual application of paint, which can reflect the ability of paint to redisperse after standing, stratifying or precipitating during storage, transportation and use. In industrial production, paint needs to go through storage, transportation and other links from production to use, and may stratify, flocculate or precipitate due to temperature changes or long-term standing. If the redispersion performance is poor, it is difficult to restore the uniform state before use, which will affect the construction effect and may cause material waste and cost increase. Through this test, the formula can be optimized, suitable dispersants, stabilizers and other materials can be selected to improve product stability and ensure quality.

[0003] For example, Chinese patent application publication No. CN120253696A discloses a paint dispersion test device for drawing, which discloses a paint dispersion test device for drawing, comprising a base, a test cylinder, a double-cone type dispersion mechanism and a coagulation-preventing type grinding mechanism. The test cylinder is arranged on the upper wall of the base, the double-cone type dispersion mechanism is arranged inside the test cylinder, and the coagulation-preventing type grinding mechanism is arranged between the upper wall and the bottom wall of the test cylinder. The double-cone type dispersion mechanism comprises a centrifugal mechanism, a flow-converging mechanism and a concentration measuring mechanism. The present application provides a paint dispersion test device for drawing, which can separate particle pigments and powder pigments, and can grind the separated particle pigments into powder under the condition of avoiding the coagulation of powder pigments.

[0004] It can be seen that the prior art still has the following problems:

[0005] The detected object cannot be formed into an initial state that conforms to the actual state by adjusting the temperature module combined with gradient centrifugation for detection, and the dispersion of the detected object cannot be analyzed by simulating the dispersion process and collecting the image of the detected object. SUMMARY

[0006] Therefore, the present application provides a paint redispersion performance test method to overcome the problem that the detected object cannot be formed into an initial state that conforms to the actual state by adjusting the temperature module combined with gradient centrifugation for detection, and the dispersion of the detected object cannot be analyzed by simulating the dispersion process and collecting the image of the detected object.

[0007] To achieve the above purpose, the present application provides a paint redispersion performance test method, comprising:

[0008] Centrifuge the paint of a preset volume loaded into the centrifuge cylinder, adjust the temperature in the centrifuge cylinder by the temperature control module, and generate the initial paint combined with the gradient centrifugation method;

[0009] In the state of the centrifugal cylinder at rest, a magnetic vibrator is added to the centrifugal cylinder, the magnetic vibrator can move up and down along the limiting rod, the electromagnetic module arranged at the bottom of the centrifugal cylinder is turned on to attract the magnetic vibrator to the bottom of the centrifugal cylinder, and the hard bottom thickness of the initial paint is obtained;

[0010] The centrifugal parameters are adjusted based on the hard bottom thickness, or the test paint is generated by vibration treatment;

[0011] The centrifugal cylinder after completing the vibration treatment is inverted so that the bottom of the centrifugal cylinder is upward, the electromagnetic module is turned on to attract the magnetic vibrator to the bottom of the centrifugal cylinder, the test paint is poured out, and the magnetic vibrator is taken out, the hard block area ratio is obtained by image scanning, and the dispersion representation coefficient is generated based on the hard block area ratio and the vibration frequency;

[0012] When it is determined that the paint redispersion does not meet the preset standard based on the dispersion representation coefficient, the vibration time is increased, or the residual hard bottom image at the bottom of the centrifugal cylinder is collected to calculate a hard bottom damage value;

[0013] Based on the hard bottom damage value, it is determined that the reason why the paint redispersion does not meet the preset standard includes insufficient dispersant and collapse of the additive system;

[0014] The temperature control module is arranged on the outer wall of the centrifugal cylinder, the centrifugal parameters include the centrifugal cylinder speed and the centrifugal time, and the vibration treatment is to vibrate the centrifugal cylinder up and down.

[0015] Further, the process of generating the initial paint by adjusting the temperature in the centrifugal cylinder by the temperature control module and combining the gradient centrifugation method includes,

[0016] An environmental temperature change curve is generated based on the placement time of the paint, and the paint centrifugal time is determined;

[0017] A preset volume of paint is placed in the centrifugal cylinder, and a first centrifugal treatment is performed at a first centrifugal cylinder speed for a preset time;

[0018] The second centrifugal treatment is performed at a second centrifugal cylinder speed for a remaining time, and the temperature in the centrifugal cylinder is adjusted based on the environmental temperature change curve by the temperature control module during the second centrifugal treatment, and the initial paint is generated;

[0019] The first centrifugal cylinder speed is less than the second centrifugal cylinder speed, the preset time is positively correlated with the viscosity of the paint, and the paint centrifugal time includes the preset time and the remaining time.

[0020] Further, the process of obtaining the hard bottom thickness of the initial paint includes,

[0021] In the state of the centrifugal cylinder at rest, open the top sealing cover of the centrifugal cylinder, align the limiting rod and add the magnetic vibrating block into the centrifugal cylinder so that the magnetic vibrating block can move up and down along the limiting rod, and close the top sealing cover of the centrifugal cylinder;

[0022] Turn on the electromagnetic module arranged at the bottom of the centrifugal cylinder to attract the magnetic vibrating block to the bottom of the centrifugal cylinder, and read the height reading of the side of the magnetic vibrating block close to the top sealing cover of the centrifugal cylinder through the scale arranged on the limiting rod;

[0023] Calculate the hard bottom thickness based on the height reading and the height of the magnetic vibrating block;

[0024] Wherein, the limiting rod and the centrifugal cylinder are both transparent materials.

[0025] Further, the process of adjusting the centrifugal parameters based on the hard bottom thickness comprises,

[0026] Collect the hard bottom thickness interval of the past paint at the placement time;

[0027] If the hard bottom thickness of the initial paint is less than the first hard bottom thickness, it is determined to increase the second centrifugal cylinder speed;

[0028] If the hard bottom thickness of the initial paint is greater than the second hard bottom thickness, it is determined to reduce the second centrifugal cylinder speed;

[0029] Wherein, the first hard bottom thickness is the minimum value of the hard bottom thickness interval, and the second hard bottom thickness is the maximum value of the hard bottom thickness interval, and the first hard bottom thickness is less than the second hard bottom thickness.

[0030] Further, if the hard bottom thickness of the initial paint is greater than or equal to the first hard bottom thickness and less than or equal to the second hard bottom thickness, it is determined to perform vibrating treatment on the initial paint and record the vibrating frequency.

[0031] Further, the process of obtaining the hard block area ratio by image scanning comprises,

[0032] Invert the centrifugal cylinder after completing the vibrating treatment so that the bottom of the centrifugal cylinder is upwardly at rest, turn on the electromagnetic module to attract the magnetic vibrating block to the bottom of the centrifugal cylinder, and open the top sealing cover of the centrifugal cylinder to pour out the test paint;

[0033] Close the electromagnetic module and take out the magnetic vibrating block to rest until no paint drops, and collect the vibrating block image;

[0034] Calculate the hard block area attached to the magnetic vibrating block based on the vibrating block image to calculate the hard block area ratio.

[0035] Further, the process of generating the dispersion representation coefficient based on the hard block area ratio and the vibration frequency comprises,

[0036] Generating a dispersion area ratio based on the hard block area ratio;

[0037] Dividing the dispersion area ratio by the vibration frequency to determine the dispersion representation coefficient.

[0038] Further, when the dispersion representation coefficient is less than a second preset representation coefficient, it is determined that the paint redispersion does not meet the preset standard; when the dispersion representation coefficient is greater than or equal to a first preset representation coefficient and less than the second preset representation coefficient, the vibration time is increased; and when the dispersion representation coefficient is less than the first preset representation coefficient, the remaining hard bottom image at the bottom of the centrifugal cylinder is collected to calculate a hard bottom damage value.

[0039] Further, the hard bottom damage value is the ratio of the remaining hard bottom area at the bottom of the centrifugal cylinder to the area at the bottom of the centrifugal cylinder.

[0040] Further, when the hard bottom damage value is less than a preset damage value, it is determined that the reason for not meeting the preset standard is that the dispersant is insufficient; and when the hard bottom damage value is greater than or equal to the preset damage value, it is determined that the reason for not meeting the preset standard is that the auxiliary agent system collapses.

[0041] Compared with the prior art, the beneficial effects of the present application are that the present application adjusts the temperature in the centrifugal cylinder through the temperature control module and generates the initial paint in combination with the gradient centrifugation method. This method can accurately control the preparation environment and process of the initial paint, and ensure that the generated paint sample is closer to the real state in terms of component distribution, particle state, etc. The temperature control module can simulate the influence of different temperature conditions on the paint, avoiding the deviation of sample properties caused by temperature fluctuations. The gradient centrifugation can make the particles, auxiliary agents, etc. in the paint distribute in a reasonable gradient by gradually adjusting the centrifugal force, reducing the problems of local agglomeration and uneven dispersion that may be caused by manual mixing or single centrifugation. The initial paint sample generated in this way has higher stability and more uniform state, providing a standardized benchmark for subsequent redispersion performance testing. When evaluating the redispersion ability of the paint after standing and stratification in the test, the consistency of the initial sample is stronger, and the test results can more truly reflect the performance differences of the paint itself rather than the errors in the preparation process. Therefore, the present application effectively eliminates interference factors and improves the accuracy of paint redispersion performance testing,

[0042] Further, the application can add the magnetic vibrating block into the centrifugal cylinder by opening the top sealing cover of the centrifugal cylinder in the state of static placement, aligning the limiting rod, and moving the magnetic vibrating block up and down along the limiting rod, close the top sealing cover of the centrifugal cylinder, open the electromagnetic module arranged at the bottom of the centrifugal cylinder to attract the magnetic vibrating block to the bottom of the centrifugal cylinder, read the height reading of the side of the magnetic vibrating block close to the top sealing cover of the centrifugal cylinder through the scale arranged on the limiting rod, calculate the hard bottom thickness based on the height reading and the height of the magnetic vibrating block, adjust the centrifugal parameters according to the hard bottom thickness, and accurately measure the hard bottom thickness formed after the paint is placed through the cooperation of the magnetic vibrating block and the electromagnetic module, which provides a quantitative index for evaluating the paint deposition state. The scale design on the limiting rod makes the height reading intuitive and controllable, and the hard bottom thickness data calculated based on the height of the magnetic vibrating block is objective and accurate. By accurately capturing the hard bottom state and optimizing the test conditions, the re-dispersion ability of the paint can be more truly reflected, the reliability of the test results can be effectively improved, and the accuracy of the paint re-dispersion performance test is further improved.

[0043] Further, the application can add the magnetic vibrating block into the centrifugal cylinder by opening the top sealing cover of the centrifugal cylinder in the state of static placement, aligning the limiting rod, and moving the magnetic vibrating block up and down along the limiting rod, close the top sealing cover of the centrifugal cylinder, open the electromagnetic module arranged at the bottom of the centrifugal cylinder to attract the magnetic vibrating block to the bottom of the centrifugal cylinder, read the height reading of the side of the magnetic vibrating block close to the top sealing cover of the centrifugal cylinder through the scale arranged on the limiting rod, calculate the hard bottom thickness based on the height reading and the height of the magnetic vibrating block, adjust the centrifugal parameters according to the hard bottom thickness, and accurately measure the hard bottom thickness formed after the paint is placed through the cooperation of the magnetic vibrating block and the electromagnetic module, which provides a quantitative index for evaluating the paint deposition state. The scale design on the limiting rod makes the height reading intuitive and controllable, and the hard bottom thickness data calculated based on the height of the magnetic vibrating block is objective and accurate. By accurately capturing the hard bottom state and optimizing the test conditions, the re-dispersion ability of the paint can be more truly reflected, the reliability of the test results can be effectively improved, and the accuracy of the paint re-dispersion performance test is further improved.

[0044] Further, the present application calculates the area proportion of the remaining hard bottom by collecting the image of the hard bottom remaining at the bottom of the centrifugal cylinder after the vibration treatment is completed, analyzes the reason for the non-conformance of the paint redispersion to the redispersion standard according to the size of the remaining hard bottom area, determines that the reason is insufficient dispersant if the size of the remaining hard bottom area is small, adjusts the proportion of the dispersant in the subsequent paint production, determines that the reason is the collapse of the additive system if the size of the remaining hard bottom area is large, adjusts the proportion of each component affecting the paint dispersion in the subsequent paint production, and converts the unqualified result of the paint redispersion performance into quantifiable remaining hard bottom area data through image collection and area calculation, so that the characterization of the performance defects is more specific and objective, the hierarchical attribution is performed based on the size of the remaining hard bottom area, the in-depth analysis of the unqualified nature is realized, the production formula is adjusted according to the unqualified reason analysis, the closed loop of the test data and production optimization is formed, the improvement of the paint redispersion performance defects is more targeted, and the accuracy of the paint redispersion performance test is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 It is a flowchart of the paint redispersion performance test method of the present application;

[0046] Figure 2 It is a structural schematic diagram of the inverted centrifugal cylinder of the embodiment of the present application;

[0047] Figure 3 It is a logic diagram for determining whether the paint redispersion conforms to the preset standard of the embodiment of the present application;

[0048] Figure 4 It is a logic diagram for determining the reason for the non-conformance to the preset standard of the embodiment of the present application;

[0049] 1, centrifugal cylinder; 2, magnetic vibration block; 3, limiting rod; 4, electromagnetic module; 5, bottom of the centrifugal cylinder. DETAILED DESCRIPTION

[0050] In order to make the purpose and advantages of the present application clearer and more apparent, the present application is further described below in conjunction with the embodiments; it should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0051] The preferred embodiments of the present application are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present application and do not limit the protection scope of the present application.

[0052] It should be noted that in the description of the present application, unless otherwise explicitly specified and limited, the term "connection" should be understood broadly, for example, it can be fixedly connected, or detachably connected, or integrally connected, it can be mechanically connected, or electrically connected, it can be directly connected, or indirectly connected through an intermediate medium, and it can be internal communication of two elements. For those skilled in the art, the specific meaning of the above-mentioned term in the present application can be understood according to the specific circumstances.

[0053] Please refer to Figure 1 As shown in the flowchart of the paint redispersion performance test method of the present application, the paint redispersion performance test method in the embodiment of the present application comprises:

[0054] Step S1, centrifuging the paint of a preset volume loaded into the centrifuge cylinder, adjusting the temperature in the centrifuge cylinder through the temperature control module and generating the initial paint by combining the gradient centrifugation mode;

[0055] Step S2, under the state of the centrifuge cylinder being at rest, adding the magnetic vibrating block to the centrifuge cylinder, the magnetic vibrating block being capable of moving up and down along the limiting rod, starting the electromagnetic module arranged at the bottom of the centrifuge cylinder to attract the magnetic vibrating block to the bottom of the centrifuge cylinder, and obtaining the hard bottom thickness of the initial paint;

[0056] Step S3, adjusting the centrifugation parameters based on the hard bottom thickness, or generating the test paint by vibrating treatment;

[0057] Step S4, inverting the centrifuge cylinder after the vibrating treatment is completed so that the bottom of the centrifuge cylinder is upward, starting the electromagnetic module to attract the magnetic vibrating block to the bottom of the centrifuge cylinder, pouring out the test paint and taking out the magnetic vibrating block, obtaining the hard block area ratio through image scanning, and generating the dispersion representation coefficient based on the hard block area ratio and the vibrating frequency;

[0058] Step S5, when the paint redispersion does not meet the preset standard based on the dispersion representation coefficient, increasing the vibrating time, or collecting the image of the remaining hard bottom at the bottom of the centrifuge cylinder to calculate the hard bottom damage value;

[0059] Step S6, determining that the reasons for the paint redispersion not meeting the preset standard include insufficient dispersant and collapse of the additive system based on the hard bottom damage value;

[0060] The temperature control module is arranged on the outer wall of the centrifuge cylinder, the centrifugation parameters include the rotation speed and the centrifugation time of the centrifuge cylinder, and the vibrating treatment is to vibrate the centrifuge cylinder up and down.

[0061] It can be understood that the preset volume of paint is loaded into the centrifugal cylinder, in order to make the vibration treatment proceed smoothly, the preset volume is generally half to two-thirds of the volume of the centrifugal cylinder, if the volume is too small, the amount of paint in the centrifugal cylinder is less, and the hard block of paint is not easy to disperse when vibrating; if the volume is too large, the remaining space cannot make the paint flow and mix fully when vibrating, reducing the vibration effect.

[0062] It can be understood that the initial vibration treatment generates test paint, and the vibration time is generally 3-8 minutes, and the vibration frequency is 50-120 times per minute. Low viscosity paint is vibrated for a short time and low frequency, and high viscosity paint is vibrated for a long time and high frequency. It can be combined by those skilled in the art, and will not be repeated here.

[0063] It can be understood that when the vibration treatment is carried out, the vibration block vibrates up and down in the centrifugal cylinder, and a single vibration is a complete vibration by impacting the top of the centrifugal cylinder and the bottom of the centrifugal cylinder.

[0064] It can be understood that the temperature control module is fixed on the outer wall of the centrifugal cylinder through the metal clamp and the heat pad, the clamp is tightened by the bolt, and a layer of 0.5-1mm thick heat-conducting silica gel pad is clamped between the module and the cylinder wall. When the vibration treatment is carried out, the temperature control module is removed first.

[0065] Please refer to Figure 2 As shown in the figure, the centrifugal cylinder 1 is placed upside down, the limiting rod 3 is arranged inside the centrifugal cylinder 1, one end is fixed and closed with the bottom 5 of the centrifugal cylinder, the other end is open and communicated with the air and internally provided with a plurality of scale lines, the magnetic vibration block 2 is added into the centrifugal cylinder from the open end of the limiting rod 3 and can move freely up and down along the limiting rod 3, and the electromagnetic module 4 is arranged outside the bottom 5 of the centrifugal cylinder and can generate magnetic attraction force to the magnetic vibration block 2 by controlling current.

[0066] Specifically, in step S1, the process of adjusting the temperature in the centrifugal cylinder by the temperature control module and generating the initial paint by the gradient centrifugation method includes,

[0067] Generating an ambient temperature change curve according to the placement time of the paint and determining the centrifugation time of the paint;

[0068] Put a preset volume of paint into the centrifugal cylinder, and carry out first centrifugation treatment for a preset time at a first centrifugal cylinder speed;

[0069] Adjust to the second centrifugal cylinder speed to carry out the second centrifugation treatment for the remaining time, and adjust the temperature in the centrifugal cylinder based on the ambient temperature change curve by the temperature control module during the second centrifugation treatment, to generate the initial paint;

[0070] The first centrifugal cylinder rotation speed is less than the second centrifugal cylinder rotation speed, the preset time is positively correlated with the paint viscosity, and the paint centrifugal time includes the preset time and the remaining time.

[0071] In a specific embodiment, the paint placement time is set to 1 year, and an environmental temperature change curve simulating four seasons in 1 year is generated. Specifically, in the first to third months (winter), the temperature gradually decreases from 5°C to 0°C, with an average decrease of about 1.67°C per month; in the fourth to sixth months (spring), the temperature gradually increases from 0°C to 20°C, with an average increase of about 6.67°C per month; in the seventh to ninth months (summer), the temperature gradually increases from 20°C to 35°C, with an average increase of about 5°C per month; in the tenth to twelfth months (autumn), the temperature gradually decreases from 35°C to 5°C, with an average decrease of about 10°C per month; according to the principle that the preset time is positively correlated with the paint viscosity, the total paint centrifugal time is determined to be 90 minutes, wherein the preset time is 45 minutes and the remaining time is 45 minutes; a centrifugal cylinder with a capacity of 1000 ml is prepared, 500 ml of paint placed for 1 year is slowly poured into the centrifugal cylinder, and the paint is ensured not to spill and the inner wall of the centrifugal cylinder is clean; the centrifugal cylinder is placed in a centrifuge, the first centrifugal cylinder rotation speed is set to 1500 r / min, the centrifuge is started, and the first centrifugal treatment of 45 minutes is performed; the rotation speed is selected because a lower rotation speed is required at the initial stage to allow the paint to preliminarily settle; after the first centrifugal treatment, the rotation speed of the centrifuge is adjusted to 3000 r / min (the second centrifugal cylinder rotation speed), and the second centrifugal treatment of 45 minutes is performed. The rotation speed is higher than the first rotation speed, which can further promote the formation of a hard bottom in the paint; during the second centrifugal treatment, the temperature in the centrifugal cylinder is adjusted by the temperature control module based on the generated environmental temperature change curve. The specific adjustment method is: according to the time ratio, the temperature change curve corresponding to 1 year in the second centrifugal time of 45 minutes is adjusted in proportion. That is, in the first 11.25 minutes (corresponding to 1-3 months), the temperature gradually decreases from 5°C to 0°C, with an average decrease of about 0.044°C per minute; in the 11.26th to 22.5th minute (corresponding to 4-6 months), the temperature gradually increases from 0°C to 20°C, with an average increase of about 0.178°C per minute; in the 22.6th to 33.75th minute (corresponding to 7-9 months), the temperature gradually increases from 20°C to 35°C, with an average increase of about 0.111°C per minute; in the 33.76th to 45th minute (corresponding to 10-12 months), the temperature gradually decreases from 35°C to 5°C, with an average decrease of about 0.222°C per minute; after the second centrifugal treatment, the initial paint with a hard bottom can be generated.

[0072] Specifically, the present application adjusts the temperature in the centrifugal cylinder through the temperature control module and generates the initial paint in combination with the gradient centrifugation method, which can accurately control the preparation environment and process of the initial paint, ensure that the generated paint sample is closer to the real state in terms of component distribution, particle state and the like, the temperature control module can simulate the influence of different temperature conditions on the paint, and avoid the deviation of the sample properties caused by temperature fluctuations; and the gradient centrifugation can make the particles, additives and other components in the paint distribute in a reasonable gradient by gradually adjusting the centrifugal force, reduce the problems of local agglomeration and uneven dispersion that may be caused by manual mixing or single centrifugation, and thus the initial paint sample generated has higher stability and more uniform state, providing a standardized benchmark for subsequent redispersion performance test, when evaluating the redispersion ability of the paint after standing and stratification in the test, because the consistency of the initial sample is stronger, the test results can more truly reflect the performance difference of the paint itself rather than the error in the preparation process, thereby effectively eliminating the interference factors and improving the accuracy of the paint redispersion performance test,

[0073] Specifically, in step S2, the process of obtaining the hard bottom thickness of the initial paint includes,

[0074] In the state of the centrifugal cylinder standing, the top sealing cover of the centrifugal cylinder is opened, the magnetic vibrating block is added into the centrifugal cylinder by aligning the limiting rod, so that the magnetic vibrating block can move up and down along the limiting rod, and the top sealing cover of the centrifugal cylinder is closed.

[0075] The electromagnetic module arranged at the bottom of the centrifugal cylinder is turned on to attract the magnetic vibrating block to the bottom of the centrifugal cylinder, and the height reading of the side of the magnetic vibrating block close to the top sealing cover of the centrifugal cylinder is read through the scale arranged on the limiting rod.

[0076] The hard bottom thickness is calculated based on the height reading and the height of the magnetic vibrating block.

[0077] The limiting rod and the centrifugal cylinder are both transparent materials.

[0078] It can be understood that the electromagnetic module arranged at the bottom of the centrifugal cylinder is turned on to attract the magnetic vibrating block to the bottom of the centrifugal cylinder, and the scale reading is read from the open end of the limiting rod. Since the electromagnetic module has an attractive force on the magnetic vibrating block, and the hard bottom is mainly formed by the close packing of pigment particles, film-forming substances and the like, and there are still a small amount of voids or movable intermolecular structures inside, under the action of electromagnetic force, the magnetic vibrating block compresses the hard bottom to make its thickness smaller, and reading the scale reading from the open end of the limiting rod is to look down at the scale line of the limiting rod, so the scale number read is larger, and the calculated hard bottom thickness is larger, and the errors of the two are offset.

[0079] Specifically, in step S3, the process of adjusting the centrifugal parameters based on the hard bottom thickness includes,

[0080] Collect the hard bottom thickness range of past paints under the placement time;

[0081] If the hard bottom thickness of the initial paint is less than the first hard bottom thickness, it is determined to increase the second centrifugal drum rotation speed;

[0082] If the hard bottom thickness of the initial paint is greater than the second hard bottom thickness, it is determined to decrease the second centrifugal drum rotation speed;

[0083] The first hard bottom thickness is the minimum value of the hard bottom thickness range, and the second hard bottom thickness is the maximum value of the hard bottom thickness range, and the first hard bottom thickness is less than the second hard bottom thickness.

[0084] In one specific embodiment, 30 past paint samples of the same type as the target paint and with a placement time of 1 year are selected (ensure consistent storage conditions and initial ingredients); for each sample, a digital caliper with a precision of 0.01 mm is used to measure the hard bottom thickness, and 3 different positions (edge, center, 1 / 2 radius) are measured for each sample, and the average value is taken as the hard bottom thickness of the sample; the thickness data of the 30 samples is counted to obtain a hard bottom thickness range of 2.5 mm (minimum value) to 4.5 mm (maximum value), the first hard bottom thickness is 2.5 mm, the second hard bottom thickness is 4.5 mm, the first centrifugal rotation speed is 1500 r / min x 45 min, the second centrifugal rotation speed is 3000 r / min x 45 min, and the temperature is adjusted according to the 1-year curve to obtain the initial paint to be detected. The hard bottom thickness of the initial paint is measured, and if the hard bottom thickness of the initial paint is 1.5 mm, which is less than the first hard bottom thickness, it is determined to increase the second centrifugal drum rotation speed; if the hard bottom thickness of the initial paint is 5.5 mm, which is greater than the second hard bottom thickness, it is determined to decrease the second centrifugal drum rotation speed; if the hard bottom thickness of the initial paint is 3.0 mm, which is greater than the first hard bottom thickness and less than the second hard bottom thickness, it is determined that the hard bottom thickness is qualified, the initial paint is vibrated and the vibration frequency is recorded.

[0085] Specifically, in step S3, if the hard bottom thickness of the initial paint is greater than or equal to the first hard bottom thickness and less than or equal to the second hard bottom thickness, it is determined that the initial paint is vibrated and the vibration frequency is recorded.

[0086] Specifically, the application can enable the magnetic vibrating block to move up and down along the limiting rod by opening the top sealing cover of the centrifugal cylinder, aligning the limiting rod and adding the magnetic vibrating block into the centrifugal cylinder in a state of being stationary, closing the top sealing cover of the centrifugal cylinder, opening the electromagnetic module arranged at the bottom of the centrifugal cylinder to attract the magnetic vibrating block to the bottom of the centrifugal cylinder, reading the height reading of the side of the magnetic vibrating block close to the top sealing cover of the centrifugal cylinder through the scale arranged on the limiting rod, calculating the hard bottom thickness based on the height reading and the height of the magnetic vibrating block, adjusting the centrifugal parameters according to the hard bottom thickness, and accurately measuring the hard bottom thickness formed after the paint is stationary through the cooperation of the magnetic vibrating block and the electromagnetic module, which provides a quantitative index for evaluating the paint deposition state. The scale design on the limiting rod makes the height reading intuitive and controllable, and the hard bottom thickness data calculated based on the height of the magnetic vibrating block is objective and accurate. Through accurate capture of the hard bottom state and optimization of the test conditions, the paint redispersion capacity can be more truly reflected, the reliability of the test results can be effectively improved, and the accuracy of the paint redispersion performance test is further improved.

[0087] Specifically, in step S4, the process of obtaining the hard block area ratio through image scanning includes,

[0088] Inverting the centrifugal cylinder after the vibrating treatment is completed, placing the bottom of the centrifugal cylinder upward, opening the electromagnetic module to attract the magnetic vibrating block to the bottom of the centrifugal cylinder, and opening the top sealing cover of the centrifugal cylinder to pour out the test paint.

[0089] Turning off the electromagnetic module and taking out the magnetic vibrating block to be stationary without paint dripping, collecting the vibrating block image.

[0090] Based on the vibrating block image, the hard block area attached to the magnetic vibrating block is calculated to calculate the hard block area ratio.

[0091] Specifically, the power of the electromagnetic module is turned off, and the magnetic force is completely eliminated after waiting for 10 seconds. The hard bottom broken block part of the magnetic vibrating block is clamped with a special plastic tweezers, and the image is collected. The hard block contour is identified through image processing technology, which is known to those skilled in the art and will not be described here. The hard block area is divided by the surface area of the magnetic vibrating block to obtain the hard block area ratio.

[0092] Specifically, in step S4, the process of generating a dispersion representation coefficient based on the hard block area ratio and the vibrating frequency includes,

[0093] Based on the hard block area ratio, a dispersion area ratio is calculated and generated;

[0094] The value obtained by dividing the dispersion area ratio by the vibrating frequency is determined as the dispersion representation coefficient.

[0095] It can be understood that the sum of the dispersion area ratio and the hard block area ratio is 1.

[0096] It can be understood that the hard block area ratio represents how much hard block is left on the magnetic vibrating block, and the dispersion area ratio represents the dispersion degree of the paint in the redispersion process. In combination with the vibration frequency, a specific and actual reference basis for the dispersion degree of the paint redispersion is provided. The smaller the dispersion representation coefficient is, the lower the dispersion degree of the paint redispersion is. The larger the dispersion representation coefficient is, the higher the dispersion degree of the paint redispersion is.

[0097] Please refer to Figure 3 As shown in the figure, it is a logic diagram for determining whether the paint redispersion meets the preset standard according to the embodiment of the application. In step S5, when the dispersion representation coefficient is greater than or equal to the second preset representation coefficient, it is determined that the paint redispersion meets the preset standard; when the dispersion representation coefficient is less than the second preset representation coefficient, it is determined that the paint redispersion does not meet the preset standard; when the dispersion representation coefficient is greater than or equal to the first preset representation coefficient and less than the second preset representation coefficient, the vibration time is increased, and when the dispersion representation coefficient is less than the first preset representation coefficient, the residual hard bottom image at the bottom of the centrifugal cylinder is collected to calculate the hard bottom damage value.

[0098] In a specific embodiment, the vibration frequency is 20 times, the first preset representation coefficient is 0.045, and the second preset representation coefficient is 0.04. When the dispersion representation coefficient is 0.047, which is greater than the second preset representation coefficient, it is determined that the paint redispersion meets the preset standard; when the dispersion representation coefficient is 0.043, which is greater than the first preset representation coefficient and less than the second preset representation coefficient, the vibration time is increased; and when the dispersion representation coefficient is 0.038, which is less than the first preset representation coefficient, the residual hard bottom image at the bottom of the centrifugal cylinder is collected to calculate the hard bottom damage value.

[0099] It can be understood that the first preset representation coefficient is less than the second preset representation coefficient, and the first preset representation coefficient and the second preset representation coefficient are negatively correlated with the ratio of the paint volume added to the centrifugal cylinder to the volume of the centrifugal cylinder. The more the paint added to the centrifugal cylinder is, the greater the thickness of the hard bottom generated is. In the case that the vibration frequency is unchanged, the greater the added volume is, the greater the residual hard bottom area is. Therefore, the first preset representation coefficient and the second preset representation coefficient are negatively correlated with the ratio of the paint volume added to the centrifugal cylinder to the volume of the centrifugal cylinder.

[0100] Preferably, when the vibration frequency is 20 times and the ratio of the paint volume added to the centrifugal cylinder to the volume of the centrifugal cylinder is one-half, the first preset representation coefficient is 0.045, and the second preset representation coefficient is 0.04.

[0101] When the ratio of the paint volume added to the centrifugal cylinder to the volume of the centrifugal cylinder is twelve-sevenths, the first preset representation coefficient is 0.043, and the second preset representation coefficient is 0.037.

[0102] The ratio of the volume of the paint added to the centrifugal cylinder to the volume of the centrifugal cylinder is two-thirds, the first preset representation coefficient is 0.037, and the second preset representation coefficient is 0.035.

[0103] Specifically, the application obtains the area of the hard block remaining on the magnetic vibrating block through image scanning, calculates the hard block area ratio according to the hard block area, and further obtains the dispersion area ratio, and obtains the dispersion representation coefficient of the paint in combination with the vibration frequency, and determines whether the paint redispersion meets the redispersion standard according to the dispersion representation coefficient, and when it is determined that the redispersion does not meet the redispersion standard, corresponding processing is performed according to the size of the dispersion representation coefficient deviation. The area of the hard block remaining on the magnetic vibrating block is obtained through image scanning, the dispersion degree observed by the naked eye in the traditional way is converted into a specific numerical value, the deviation of subjective judgment is avoided, the dispersion representation coefficient combines the dispersion area ratio and the vibration frequency, reflects the final dispersion state of the paint, embodies the energy required to reach the state, more comprehensively describes the redispersion ability of the paint, and corresponding processing is performed according to the size of the coefficient deviation for the case that does not meet the standard, and the accuracy of the paint redispersion performance test is further improved.

[0104] Specifically, in step S5, the hard bottom damage value is the ratio of the remaining hard bottom area of the centrifugal cylinder bottom to the area of the centrifugal cylinder bottom.

[0105] Referring to Figure 4 As shown in the figure, it is a logic diagram for determining the reason for not meeting the preset standard in the embodiment of the application, and in step S6, when the hard bottom damage value is less than the preset damage value, it is determined that the reason for not meeting the preset standard is that the dispersant is insufficient, and when the hard bottom damage value is greater than or equal to the preset damage value, it is determined that the reason for not meeting the preset standard is that the additive system collapses.

[0106] In a specific embodiment, the preset damage value is set to 10%, if the hard bottom damage value is 8% and less than the preset damage value, it is determined that the reason for not meeting the preset standard is that the dispersant is insufficient, and if the hard bottom damage value is 16% and greater than the preset damage value, it is determined that the reason for not meeting the preset standard is that the additive system collapses.

[0107] It can be understood that the preset damage value is positively correlated with the vibration frequency, the greater the vibration frequency, the less the remaining hard block of the centrifugal cylinder bottom, and therefore the preset damage value is positively correlated with the vibration frequency.

[0108] Preferably, when the vibration frequency is 20 times, the preset damage value is 15%;

[0109] When the vibration frequency is 30 times, the preset damage value is 10%;

[0110] When the vibration frequency is 50 times, the preset damage value is 5%.

[0111] Specifically, the present application collects the image of the hard bottom remaining at the bottom of the centrifugal cylinder after the completion of the vibration treatment, calculates the area ratio of the remaining hard bottom, analyzes the reason for the non-conformance of the paint redispersion according to the size of the remaining hard bottom area, if the size of the remaining hard bottom area is small, it is determined that the reason is the lack of dispersant, and the proportion of dispersant in subsequent paint production is adjusted, if the size of the remaining hard bottom area is too large, it is determined that the reason is the collapse of the additive system, and the proportion of each component affecting the paint dispersion in subsequent paint production is adjusted, through image acquisition and area calculation, the unqualified result of the paint redispersion performance is converted into quantifiable remaining hard bottom area data, the performance defect is more specific and objective, the hierarchical attribution is carried out based on the size of the remaining hard bottom area, the in-depth analysis of the unqualified nature is realized, the production formula is adjusted according to the unqualified reason analysis, the test data and production optimization form a closed loop, the improvement of the paint redispersion performance defect is more targeted, and the accuracy of the paint redispersion performance test is further improved.

[0112] So far, the technical solutions of the present application have been described in combination with the preferred embodiments shown in the drawings, but those skilled in the art can easily understand that the protection scope of the present application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without departing from the principles of the present application, and the technical solutions after the changes or replacements will fall within the protection scope of the present application.

[0113] The above description is only the preferred embodiments of the present application and is not used to limit the present application; for those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for testing the redispersibility of paint, characterized in that, include: The paint, which is loaded into a centrifuge tube of a preset volume, is centrifuged. The temperature inside the centrifuge tube is adjusted by the temperature control module and combined with gradient centrifugation to generate the initial paint. With the centrifuge tube in a static state, a magnetic vibrating block is added to the centrifuge tube. The magnetic vibrating block can move up and down along the limiting rod. The electromagnetic module set at the bottom of the centrifuge tube is activated to attract the magnetic vibrating block to the bottom of the centrifuge tube, thereby obtaining the initial hard base thickness of the paint. Based on the comparison results of the hard base thickness and the hard base thickness range, it is determined whether to adjust the centrifugation parameters or perform vibration treatment to generate test paint. Invert the centrifuge tube after vibration treatment so that the bottom of the centrifuge tube is facing upward. Turn on the electromagnetic module to attract the magnetic vibration block to the bottom of the centrifuge tube. Pour out the test paint and take out the magnetic vibration block. Obtain the hard block area ratio by image scanning. Generate a dispersion characterization coefficient based on the hard block area ratio and the number of vibrations. When the paint redispersion does not meet the preset standard based on the dispersion characterization coefficient, the vibration time is increased or the image of the remaining hard bottom at the bottom of the centrifuge tube is collected to calculate the hard bottom damage value based on the comparison result of the dispersion characterization coefficient and several preset characterization coefficients. Based on the hard base breakage value, the reasons why the paint redispersion does not meet the preset standard include insufficient dispersant and failure of the additive system; The temperature control module is located on the outer wall of the centrifuge tube, the centrifugation parameters include the centrifuge tube speed and centrifugation time, and the vibration treatment is to vibrate the centrifuge tube up and down.

2. The method for testing the redispersibility of paint according to claim 1, characterized in that, The process of adjusting the temperature inside the centrifuge tube using a temperature control module and generating the initial paint using a gradient centrifugation method includes: A temperature change curve is generated based on the paint's storage time, and the paint centrifugation time is determined. Place a preset volume of paint into a centrifuge cylinder and perform a first centrifugation process for a preset time at the first centrifuge cylinder speed. The second centrifuge cycle is adjusted to the second centrifuge drum speed for the remaining time. During the second centrifuge process, the temperature inside the centrifuge drum is adjusted by the temperature control module based on the ambient temperature change curve to generate the initial paint. Wherein, the rotational speed of the first centrifuge tube is less than that of the second centrifuge tube, the preset time is positively correlated with the viscosity of the paint, and the paint centrifugation time includes the preset time and the remaining time.

3. The method for testing the redispersibility of paint according to claim 2, characterized in that, The process of obtaining the initial hard base thickness of the paint includes, With the centrifuge tube in a static state, open the top sealing cover of the centrifuge tube, align the magnetic vibrating block with the limiting rod, add the magnetic vibrating block into the centrifuge tube so that the magnetic vibrating block can move up and down along the limiting rod, and close the top sealing cover of the centrifuge tube. Turn on the electromagnetic module located at the bottom of the centrifuge tube to attract the magnetic vibrating block to the bottom of the centrifuge tube, and read the height of the magnetic vibrating block near the top sealing cover of the centrifuge tube by means of the scale set on the limit rod. The thickness of the hard base is calculated based on the height reading and the height of the magnetic vibrating block. Both the limiting rod and the centrifuge cylinder are made of transparent material.

4. The method for testing the redispersibility of paint according to claim 3, characterized in that, The process of adjusting the centrifugation parameters based on the hard base thickness includes: Collect data on the hardened base thickness range of past paints during the stated placement time; If the initial hard base thickness of the paint is less than the first hard base thickness, then it is determined that the rotation speed of the second centrifuge should be increased. If the initial hard base thickness of the paint is greater than the second hard base thickness, then it is determined that the rotation speed of the second centrifuge should be reduced. Wherein, the first hard sole thickness is the minimum value of the hard sole thickness range, the second hard sole thickness is the maximum value of the hard sole thickness range, and the first hard sole thickness is less than the second hard sole thickness.

5. The method for testing the redispersibility of paint according to claim 4, characterized in that, If the initial paint hardening thickness is greater than or equal to the first hardening thickness and less than or equal to the second hardening thickness, then it is determined that the initial paint should be vibrated and the number of vibrations should be recorded.

6. The method for testing the redispersibility of paint according to claim 5, characterized in that, The process of obtaining the hard block area ratio through image scanning includes: Invert the centrifuge tube after vibration treatment so that the bottom of the centrifuge tube faces upward and stand still. Turn on the electromagnetic module to attract the magnetic vibration block to the bottom of the centrifuge tube. Open the top sealing cover of the centrifuge tube and pour out the test paint. Turn off the electromagnetic module, remove the magnetic vibratory block and let it stand until no paint drips down, then capture an image of the vibratory block; The area of ​​the hard block attached to the magnetic vibratory block is calculated based on the image of the vibratory block to calculate the area ratio of the hard block.

7. The method for testing the redispersibility of paint according to claim 6, characterized in that, The process of generating the dispersion characterization coefficient based on the area ratio of the hard block and the number of vibrations includes: The proportion of dispersed area is calculated based on the proportion of the hard block area. The value obtained by dividing the proportion of the dispersed area by the number of vibrations is determined as the dispersion characterization coefficient.

8. The method for testing the redispersibility of paint according to claim 7, characterized in that, When the dispersion characterization coefficient is less than the second preset characterization coefficient, it is determined that the paint redispersion does not meet the preset standard; when the dispersion characterization coefficient is greater than or equal to the first preset characterization coefficient and less than the second preset characterization coefficient, the vibration time is increased; and when the dispersion characterization coefficient is less than the first preset characterization coefficient, the remaining hard bottom image at the bottom of the centrifuge is collected to calculate the hard bottom damage value.

9. The method for testing the redispersibility of paint according to claim 8, characterized in that, The hard bottom damage value is the ratio of the remaining hard bottom area at the bottom of the centrifuge tube to the total area of ​​the bottom of the centrifuge tube.

10. The method for testing the redispersibility of paint according to claim 9, characterized in that, When the hard bottom breakage value is less than the preset breakage value, the reason for not meeting the preset standard is determined to be insufficient dispersant; when the hard bottom breakage value is greater than or equal to the preset breakage value, the reason for not meeting the preset standard is determined to be the collapse of the additive system.

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