A method for preparing a fast hydrophobic rain-repellent coating

Abstract

The present invention relates to the technical field of preparation of a bullet rain agent coating, and in particular to a method for preparing a fast hydrophobic bullet rain agent coating. The method comprises: preparing a dispersion liquid, and determining whether to continue stirring or record the bubble disappearance time after shaking the dispersion liquid based on whether the rising trajectory of bubbles is regular and the rising speed is stable during the preparation and stirring of the dispersion liquid; preparing a mixed solution, and determining the addition rate of a water-based acrylic resin and the weight of a polyether-modified organic silicon compound based on the bubble disappearance time recorded after shaking the dispersion liquid; determining the spraying distance and spraying pressure of the mixed solution based on the addition rate of the water-based acrylic resin and the weight of the polyether-modified organic silicon compound; and determining whether to adjust the minimum value of a preset bubble disappearance time range and the weight of an ammonia-based drying agent based on the curing time of the coating. The present invention improves the fast hydrophobicity of the prepared bullet rain agent coating by improving the accuracy of control over the preparation process of the bullet rain agent coating.

Description

Technical Field

[0001] The present invention relates to the technical field of preparation of bullet rain agent coatings, in particular to a preparation method of a fast hydrophobic bullet rain agent coating. Background Art

[0002] When driving a car, the rearview mirror is an important device for the driver to obtain information about the rear of the vehicle. Its clarity is directly related to driving safety. However, in rainy environments, rainwater easily adheres to the surface of the rearview mirror, forming water droplets or water films, seriously obstructing the driver's vision and greatly increasing driving risks. Although traditional rearview mirrors have certain waterproof functions, the effect is often unsatisfactory and it is difficult to maintain good clarity in severe weather conditions such as heavy rain.

[0003] Chinese patent application publication number: CN119060631A discloses a method for preparing a rearview mirror anti-static agent coating, which includes pre-treating the rearview mirror surface; determining a difficult-to-apply area based on the curvature and roughness of the rearview mirror area to be coated, and determining a coating method for the coating raw material mixture based on the difficult-to-apply area and the complexity of the shape of the rearview mirror to be coated; judging whether the rearview mirror anti-static agent coating obtained after the coating is completed is evenly coated; monitoring the contact angle of water droplets on the evenly coated rearview mirror anti-static agent coating surface, and determining whether to adjust the preparation process parameters of the rearview mirror anti-static agent coating based on the average decrease rate of the contact angle within a preset time and the difference between the maximum decrease rate of the contact angle within a preset time and the average decrease rate; the invention obtains a high-performance rearview mirror anti-static agent coating by improving the accuracy of the control of the preparation process of the rearview mirror anti-static agent coating.

[0004] It can be seen that the existing technology has the problem of insufficiently precise control over the preparation process of the bullet rain agent coating, resulting in poor hydrophobicity of the prepared bullet rain agent coating. Summary of the Invention

[0005] To this end, the present invention provides a method for preparing a fast hydrophobic bullet rain agent coating, so as to overcome the problem in the prior art that the control of the bullet rain agent coating preparation process is not precise enough, resulting in poor hydrophobic performance of the prepared bullet rain agent coating.

[0006] To achieve the above object, the present invention provides a method for preparing a fast hydrophobic rain-repellent coating, comprising:

[0007] 8-10 parts of nano-sized titanium dioxide particles modified with special fluorosilane, 1-3 parts of nano-sized zirconium oxide particles, 28-30 parts of water-based acrylic resin, 1-3 parts of sodium polyacrylate dispersant, 0.6-1 part of polyether-modified organosilicon compound, 0.6-0.9 parts of ammonia drier and 55-60 parts of deionized water are selected as the preparation raw materials;

[0008] Deionized water, nano-sized titanium dioxide particles modified with special fluorosilane, nano-sized zirconium oxide particles, and a sodium polyacrylate dispersant are sequentially added to a stirring container and stirred to obtain a dispersion. Based on whether the rising trajectory of the bubbles is regular and the rising speed is stable during stirring, the time it takes for the bubbles to disappear after continuing stirring or shaking the dispersion is recorded.

[0009] Adding a water-based acrylic resin, a polyether-modified organosilicon compound, and an ammonia-based drier to the dispersion in sequence and stirring to obtain a mixed solution, and determining the addition rate of the water-based acrylic resin and the weight of the polyether-modified organosilicon compound by recording the time it takes for bubbles to disappear after shaking the dispersion;

[0010] Determining the spraying distance and spraying pressure of the mixed solution based on the addition rate of the water-based acrylic resin and the weight of the polyether-modified organosilicon compound;

[0011] After spraying is completed, the object is placed in a ventilated environment to allow the coating to solidify, thereby obtaining a rain-repellent coating with rapid hydrophobicity. Based on the coating solidification time, it is determined whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drying agent.

[0012] Further, determining the time it takes for bubbles to disappear after continuing to stir or record the shaking of the dispersion includes:

[0013] If the rising trajectory of the bubbles during stirring is regular and the rising speed is stable, determine and record the time it takes for the bubbles to disappear after shaking the dispersion;

[0014] If the rising trajectory of the bubbles is irregular or the rising speed is unstable during stirring, continue stirring.

[0015] Furthermore, determining whether the rising trajectory of the bubbles during the stirring process is regular includes:

[0016] A high-speed camera is used to obtain image data of the stirring process of the dispersion in the stirring container;

[0017] Grayscale the captured image and convert the color image into a grayscale image;

[0018] An image recognition algorithm is used to identify the position and outline of each bubble, and then a tracking algorithm based on feature point matching is used to record the bubble's trajectory.

[0019] The curvature and direction change rate of each bubble's trajectory are calculated. If the curvature and direction change rate of the bubble are both within a preset range within a preset time period, the rising trajectory rule of the bubble is determined.

[0020] Furthermore, the preset change range of the curvature of the bubble within the preset time length is determined according to the change range of the curvature of the bubble within several preset time lengths, and the preset change range of the direction change rate of the bubble within the preset time length is determined according to the change range of the direction change rate of the bubble within several preset time lengths.

[0021] Furthermore, determining whether the rising speed of the bubbles during the stirring process is stable includes:

[0022] After the image acquisition is completed, a vertical monitoring area is delineated in the image according to the size and shape of the mixing container. The monitoring area covers the path of the rising bubbles.

[0023] Determine the vertical coordinates of the bubble in the monitoring area through the identified bubble position and contour information;

[0024] According to the vertical coordinate changes of the bubble in the continuous multi-frame images and the shooting frame rate, the rising distance of the bubble in unit time is calculated to obtain the rising speed;

[0025] The average value of the bubble rising speed within the preset time length is calculated, and then the deviation of each calculated rising speed from the average value is compared. If each deviation is within the preset speed fluctuation threshold range, it is determined that the bubble rising speed is stable.

[0026] Furthermore, the preset speed fluctuation threshold range is determined according to the maximum value of the bubble rising speed within a number of preset time periods.

[0027] Furthermore, determining the addition rate of the waterborne acrylic resin and the weight of the polyether-modified silicone compound includes:

[0028] If the bubble disappearance time recorded after shaking the dispersion is greater than a maximum value of a preset bubble disappearance time range, determining that the addition rate of the water-based acrylic resin is a first addition rate and the weight of the polyether-modified organosilicon compound is a first weight;

[0029] If the bubble disappearance time recorded after shaking the dispersion is within the preset bubble disappearance time range, the addition rate of the waterborne acrylic resin is determined to be the original addition rate and the weight of the polyether-modified organosilicon compound is determined to be the original weight;

[0030] If the bubble disappearance time recorded after shaking the dispersion is less than the minimum value of the preset bubble disappearance time range, the addition speed of the water-based acrylic resin is determined to be the second addition speed and the weight of the polyether-modified silicone compound is determined to be the second weight.

[0031] Further, determining the spraying distance and spraying pressure of the mixed solution includes:

[0032] If the addition speed of the water-based acrylic resin is greater than a preset addition speed and the weight of the polyether-modified organosilicon compound is greater than a preset weight, determining the spraying distance of the mixed solution to be a first spraying distance and determining the spraying pressure of the mixed solution to be a first spraying pressure;

[0033] If the addition rate of the water-based acrylic resin is less than or equal to the preset addition rate or the weight of the polyether-modified silicone compound is less than or equal to the preset weight, the spraying distance of the mixed solution is determined to be the second spraying distance and the spraying pressure of the mixed solution is determined to be the second spraying pressure.

[0034] Furthermore, determining whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drying agent includes:

[0035] If the coating curing time is less than the minimum value of the preset coating curing time range, determining to adjust the minimum value of the preset bubble disappearance time range;

[0036] If the coating curing time is longer than a maximum value of a preset coating curing time range, it is determined that the weight of the ammonia drier is adjusted.

[0037] Furthermore, the adjustment amount of the minimum value of the preset bubble disappearance time range is negatively correlated with the coating curing time, and the adjustment amount of the weight of the ammonia drying agent is positively correlated with the coating curing time.

[0038] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention determines whether to continue stirring or record the bubble disappearance time after shaking the dispersion according to whether the rising trajectory of the bubbles is regular and whether the rising speed is stable during the stirring process. When the rising trajectory of the bubbles is irregular or the rising speed is unstable, continuing to stir can make the dispersion further mixed evenly, thereby avoiding the impact of uneven dispersion on product quality. If the rising trajectory of the bubbles is regular and the rising speed is stable, it indicates that the stirring state of the dispersion is relatively ideal. At this time, the bubble disappearance time after shaking the dispersion is recorded. By reasonably judging whether to continue stirring or record the time, the waste of resources caused by excessive stirring or insufficient stirring is avoided. Excessive stirring may consume more energy and increase equipment loss, while insufficient stirring may cause the product to be unqualified and require rework. The above method improves the accuracy of the control of the preparation process of the bullet rain agent coating, thereby improving the rapid hydrophobicity of the prepared bullet rain agent coating.

[0039] Furthermore, the present invention dynamically adjusts the addition rate of the water-based acrylic resin and the weight of the polyether-modified silicone compound according to the bubble disappearance time after shaking the dispersion, and can accurately control the performance of the product. For example, if the bubble disappearance time is greater than the maximum value of the preset range, it indicates that the current dispersion state may cause certain performance deficiencies of the product. At this time, the first addition rate and the first weight are adopted. When the bubble disappearance time is within the preset range, the original addition rate and weight are maintained to ensure the consistency of product quality; and when the bubble disappearance time deviates from the range, the parameters are reasonably adjusted to stabilize the product quality within an acceptable range again, reducing the product quality differences caused by fluctuations in the production process. According to the simple and easy-to-measure bubble disappearance time, the water-based acrylic resin addition rate and the polyether-modified silicone compound weight to be adopted are quickly determined, avoiding blind attempts and repeated experiments, and improving production efficiency. The above method improves the accuracy of the control of the preparation process of the bullet rain agent coating and thereby improves the rapid hydrophobicity of the prepared bullet rain agent coating.

[0040] Furthermore, the present invention determines the spraying distance and pressure based on the addition rate of the water-based acrylic resin and the weight of the polyether-modified silicone compound, and can accurately match the spraying parameters according to different raw material addition conditions. When the addition amount of both raw materials is greater than the preset value, a relatively large first spraying distance is used, which helps to evenly disperse the mixed solution in a larger range when the amount of raw materials is large, avoid the concentrated accumulation of paint caused by close distance and low pressure, and ensure the uniformity and quality of the coating. When the amount of raw material added is less than or equal to the preset value, a relatively small second spraying distance and a lower second spraying pressure are selected. In this way, when the amount of raw materials is small, it can be ensured that the paint can effectively cover the target surface, avoiding insufficient coverage caused by excessive dispersion of paint due to long distance and high pressure. The above method improves the accuracy of the control of the preparation process of the bullet rain agent coating and thereby improves the rapid hydrophobicity of the prepared bullet rain agent coating.

[0041] Furthermore, the present invention specifically adjusts the minimum value of the preset bubble disappearance time range or the weight of the ammonia drying agent based on the comparison result between the coating curing time and the preset range. When the coating curing time is less than the minimum value of the preset range, it indicates that the curing process is too fast. At this time, adjusting the minimum value of the preset bubble disappearance time range can reduce the weight of the polyether-modified silicone compound by affecting the early bubble-related parameters. When the coating curing time is greater than the maximum value of the preset range, it indicates that the curing is too slow, which may affect the product performance. By adjusting the weight of the ammonia drying agent, the curing speed can be effectively controlled to ensure that the coating curing effect meets the requirements and avoid product defects caused by abnormal curing time, such as insufficient coating hardness, decreased adhesion, and other problems, thereby ensuring the stability of product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1This is a workflow diagram of a method for preparing a fast hydrophobic rain-repellent coating according to an embodiment of the present invention;

[0043] Figure 2 This is a flowchart for determining whether the rising trajectory of bubbles during stirring is regular in the method for preparing a fast hydrophobic rain-repellent coating according to an embodiment of the present invention;

[0044] Figure 3 This is a flowchart of determining whether the rising speed of bubbles is stable during the stirring process in the method for preparing a fast hydrophobic rain agent coating according to an embodiment of the present invention;

[0045] Figure 4 This is a workflow diagram for determining whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drying agent in the preparation method of the rapid hydrophobic rain agent coating according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0047] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0048] See also Figure 1-Figure 4 As shown, Figure 1 This is a workflow diagram of a method for preparing a fast hydrophobic rain-repellent coating according to an embodiment of the present invention; Figure 2 This is a flowchart for determining whether the rising trajectory of bubbles during stirring is regular in the method for preparing a fast hydrophobic rain-repellent coating according to an embodiment of the present invention; Figure 3 This is a flowchart of determining whether the rising speed of bubbles is stable during the stirring process in the method for preparing a fast hydrophobic rain-repellent coating according to an embodiment of the present invention; Figure 4 This is a workflow diagram for determining whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drying agent in the preparation method of the rapid hydrophobic rain agent coating according to an embodiment of the present invention.

[0049] The method for preparing a fast hydrophobic rain-repellent coating according to an embodiment of the present invention comprises:

[0050] Step S1, selecting 8-10 parts of nano-sized titanium dioxide particles modified with special fluorosilane, 1-3 parts of nano-sized zirconium oxide particles, 28-30 parts of water-based acrylic resin, 1-3 parts of polyacrylic acid sodium salt dispersant, 0.6-1 part of polyether-modified organosilicon compound, 0.6-0.9 parts of ammonia drier, and 55-60 parts of deionized water as preparation raw materials;

[0051] Step S2, adding deionized water, nano-sized titanium dioxide particles modified with special fluorosilane, nano-sized zirconium oxide particles, and a sodium polyacrylate dispersant to a stirring container in sequence and stirring to obtain a dispersion liquid, and determining whether to continue stirring or record the bubble disappearance time after shaking the dispersion liquid based on whether the rising trajectory of the bubbles is regular and the rising speed is stable during the stirring process;

[0052] Step S3, sequentially adding a water-based acrylic resin, a polyether-modified organosilicon compound, and an ammonia-based drier to the dispersion and stirring to obtain a mixed solution, and determining the addition rate of the water-based acrylic resin and the weight of the polyether-modified organosilicon compound based on the time it takes for bubbles to disappear after shaking the dispersion;

[0053] Step S4, determining the spraying distance and spraying pressure of the mixed solution based on the addition rate of the water-based acrylic resin and the weight of the polyether-modified organosilicon compound;

[0054] Step S5, after the spraying is completed, the object is placed in a ventilated environment to solidify the coating to obtain a rain-repellent coating with rapid hydrophobicity, and based on the coating curing time, it is determined whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drying agent.

[0055] The dispersion preparation process in the embodiment of the present invention includes selecting a clean stirring container to ensure that it is free of impurities and oil, adding 200g of deionized water to the stirring container, starting stirring at a low speed of 250 rpm, slowly adding 30g of nano-sized titanium dioxide particles modified with special fluorosilane, continuing stirring, slowly adding 5g of nano-sized zirconium oxide particles, continuing stirring for 1.5 hours to preliminarily disperse the nanoparticles, adding 5g of sodium polyacrylate dispersant, increasing the stirring speed to 600 rpm, and stirring for 2.5 hours to ensure that the nanoparticles are evenly dispersed in the water to form a stable nanoparticle dispersion.

[0056] The mixed solution preparation process in the embodiment of the present invention includes slowly pouring 100g of aqueous acrylic resin into the above-mentioned nanoparticle dispersion, controlling the addition speed to be completed within 15 minutes, adding 3g of polyether-modified silicone compound, adding 2g of ammonia drying agent, maintaining the stirring speed at 600 rpm, stirring for 1.5 hours, so that the components are fully mixed to obtain a mixed solution of the rain agent coating.

[0057] Specifically, in step S2, when determining to continue stirring or recording the bubble disappearance time after shaking the dispersion, the bubble disappearance time after shaking the dispersion is determined based on whether the rising trajectory of the bubbles during the stirring process is regular and whether the rising speed is stable;

[0058] When the rising trajectory of the bubbles during stirring is regular and the rising speed is stable, the time it takes for the bubbles to disappear after shaking the dispersion is determined and recorded;

[0059] When the rising trajectory of the bubbles is irregular or the rising speed is unstable during stirring, make sure to continue stirring.

[0060] Specifically, in step S2, the step of determining whether the rising trajectory of the bubbles during the stirring process is regular includes:

[0061] Step S2101, using a high-speed camera to obtain image data of the stirring process of the dispersion in the stirring container;

[0062] Step S2102, grayscale processing is performed on the captured image to convert the color image into a grayscale image;

[0063] Step S2103: using an image recognition algorithm to identify the position and outline of each bubble, and then using a tracking algorithm based on feature point matching to record the movement trajectory of the bubble;

[0064] Step S2104 , calculating the curvature and direction change rate of each bubble's trajectory. If the curvature and direction change rate of the bubble are both within a preset range within a preset time period, the rising trajectory rule of the bubble is determined.

[0065] In the embodiment of the present invention, the value of the preset time length is set to 5 seconds, and the preset variation range of the curvature of the bubble within the preset time length is determined according to the variation range of the curvature of the bubble within several preset time lengths. The minimum value of the preset variation range of the curvature of the bubble within the preset time length is three-fifths of the average value of the curvature variation of the bubble within several preset time lengths, and the maximum value of the preset variation range of the curvature of the bubble within the preset time length is six-fifths of the average value of the curvature variation of the bubble within several preset time lengths. The preset variation range of the direction change rate of the bubble within the preset time length is determined according to the variation range of the direction change rate of the bubble within several preset time lengths. The minimum value of the preset variation range of the direction change rate of the bubble within the preset time length is three-fifths of the average value of the direction change rate of the bubble within several preset time lengths, and the maximum value of the preset variation range of the direction change rate of the bubble within the preset time length is six-fifths of the average value of the direction change rate of the bubble within several preset time lengths. However, the above values ​​are not limited to this, and those skilled in the art can also adjust the values ​​according to actual needs.

[0066] In an embodiment of the present invention, a stirring experiment of a dispersion is carried out in a rectangular stirring container with a length of 40 cm, a width of 30 cm, and a height of 60 cm. A high-speed camera with a frame rate of 50 frames per second is used to film the stirring process to monitor the movement of bubbles. The stirring device is started to stir the dispersion, and the high-speed camera is turned on at the same time to obtain image data of the stirring process of the dispersion in the stirring container. The camera continuously records the entire stirring process to ensure that complete information on the bubble movement can be captured. The captured color image is grayscaled and converted into a grayscale image, and the image recognition algorithm is used to identify the position and outline of each bubble. Here, an image recognition algorithm based on template matching is used. Bubble templates of different sizes and shapes are prepared in advance, and matching and recognition are performed in the grayscale image to determine the position and outline of each bubble. Then, a tracking algorithm based on feature point matching is used to record the movement trajectory of the bubble. Taking a certain bubble as an example, after the bubble is identified in the first frame image, its feature points (such as edge points, center of mass, etc.) are extracted, and the corresponding position of the bubble is found by feature point matching in the subsequent frame image, thereby recording its movement trajectory. The preset time length is set to 5 seconds. During these 5 seconds, the curvature and direction change rate of each bubble movement trajectory are calculated. Assuming that within 5 seconds , a series of position coordinates of a bubble are obtained through image tracking, and the curvature calculation formula of discrete points (for example, the approximate curvature is calculated based on three adjacent points) is used to calculate the curvature at each point. After calculation, a series of values ​​of the bubble curvature within 5 seconds are obtained, and the average of these curvature values ​​is calculated to determine the preset change range of the bubble curvature. Then, it is determined whether the curvature values ​​of the bubble within 5 seconds are all within the preset change range of the bubble curvature. Also within these 5 seconds, the direction change rate is calculated based on the change in the position of the bubble between adjacent frames. Assuming that the direction change angle of the bubble between the i-th frame and the i+1-th frame is θi, the direction change rate is △θi= , ( is the time interval between two adjacent frames) to obtain a series of values ​​of the bubble direction change rate within these 5 seconds, △θ1, △θ2, ..., △θ249, calculate the average value of these direction change rate values ​​and then determine the preset change range of the bubble direction change rate, and judge whether the direction change rate values ​​of the bubble within these 5 seconds are all within the preset change range of the bubble direction change rate. If, within these 5 seconds, the change range of the curvature and the direction change rate of the bubble are both within the above-mentioned preset change range, then it is determined that the rising trajectory of the bubble is regular; otherwise, it is determined that the rising trajectory of the bubble is irregular.

[0067] Specifically, in step S2, the step of determining whether the rising speed of the bubbles during the stirring process is stable includes:

[0068] Step S2201: After image acquisition is completed, a vertical monitoring area is defined in the image according to the size and shape of the stirring container, and the monitoring area covers the path of the rising bubbles;

[0069] Step S2202, determining the vertical coordinate of the bubble in the monitoring area based on the identified bubble position and contour information;

[0070] Step S2203, calculating the rising distance of the bubble per unit time based on the vertical coordinate changes of the bubble in the continuous multi-frame image and the shooting frame rate to obtain the rising speed;

[0071] Step S2204, calculate the average value of the bubble rising speed within the preset time length, and then compare the deviation of each calculated rising speed with the average value. If each deviation is within the preset speed fluctuation threshold range, it is determined that the bubble rising speed is stable.

[0072] In the embodiment of the present invention, the preset speed fluctuation threshold range is determined based on the maximum value of the bubble rising speed within several preset time periods, the minimum value of the preset speed fluctuation threshold range is three-fifths of the maximum value of the bubble rising speed within several preset time periods, and the maximum value of the preset speed fluctuation threshold range is the maximum value of the bubble rising speed within several preset time periods, but the above values ​​are not limited to this, and those skilled in the art can also adjust the values ​​according to actual needs.

[0073] The present invention defines a vertical monitoring area within the captured image based on the size and shape of the mixing container. Since the mixing container is cylindrical and bubbles rise vertically, the monitoring area is set as a vertical region extending from 20 cm to 80 cm upward from the bottom of the container. This region covers the primary path of bubble rise. An image recognition algorithm is used to identify the location and contour of the bubbles. For example, within a given frame, the contour of a bubble is identified, and the vertical coordinate of the bubble within the monitoring area is determined. Assuming that the vertical coordinate of the bubble in this frame is 30 cm from the bottom of the monitoring area (the actual distance is obtained by converting the image pixel coordinates), multiple frames of images are captured continuously, assuming 100 frames. The rising velocity of the bubble is calculated based on the change in the vertical coordinate of the bubble in these consecutive frames, combined with the capture frame rate (30 frames per second). For example, if the vertical coordinate of the bubble in the first frame is 30 cm, it will change to 35 cm in the tenth frame. If the time interval between two image frames is 0.3 seconds and the bubble rises a distance of 5 cm, the bubble's rise speed during this time is 16.67 cm / s. The preset duration is set to 5 seconds. Within these 5 seconds, multiple bubble rise speed values ​​are calculated according to step S2203. Assuming a total of 150 speed values ​​are calculated within these 5 seconds (because the frame rate is 30 frames / s), the average of these 150 speed values ​​is calculated. Assuming the average is 15 cm / s, the deviation of each speed value from the average is calculated. For example, a speed value of 16 cm / s has a deviation of 6.67% from the average. First, a preset speed fluctuation threshold range is determined. Assuming that in multiple previous tests, the maximum value of the bubble's rise speed within several preset durations (also 5 seconds) is 20 cm / s. The preset speed fluctuation threshold range has a minimum of 12 cm / s and a maximum of 20 cm / s. The deviation of each speed value from the average is compared with the preset speed fluctuation threshold range. If all speed values ​​corresponding to the deviations are within the range of 12 cm / s to 20 cm / s, the bubble's rise speed is determined to be stable.

[0074] The present invention determines whether to continue stirring or record the bubble disappearance time after shaking the dispersion liquid according to whether the rising trajectory of the bubbles is regular and whether the rising speed is stable during the stirring process. When the rising trajectory of the bubbles is irregular or the rising speed is unstable, continuing to stir can make the dispersion liquid further mixed evenly, thereby avoiding the influence of uneven dispersion on product quality. If the rising trajectory of the bubbles is regular and the rising speed is stable, it indicates that the stirring state of the dispersion liquid is relatively ideal. At this time, the bubble disappearance time after shaking the dispersion liquid is recorded. By reasonably judging whether to continue stirring or record the time, the waste of resources caused by excessive stirring or insufficient stirring is avoided. Excessive stirring may consume more energy and increase equipment loss, while insufficient stirring may cause the product to be unqualified and require rework. The above method improves the accuracy of the control of the preparation process of the bullet rain agent coating, thereby improving the rapid hydrophobicity of the prepared bullet rain agent coating.

[0075] Specifically, in step S3, when determining the addition rate of the water-based acrylic resin and the weight of the polyether-modified organic silicon compound, the addition rate of the water-based acrylic resin and the weight of the polyether-modified organic silicon compound are determined based on the time it takes for bubbles to disappear after shaking the dispersion;

[0076] When the bubble disappearance time recorded after shaking the dispersion is greater than a maximum value of a preset bubble disappearance time range, determining that the addition rate of the water-based acrylic resin is a first addition rate and the weight of the polyether-modified organosilicon compound is a first weight;

[0077] When the bubble disappearance time recorded after shaking the dispersion is within a preset bubble disappearance time range, determining that the addition rate of the waterborne acrylic resin is the original addition rate and the weight of the polyether-modified organosilicon compound is the original weight;

[0078] When the bubble disappearance time recorded after shaking the dispersion is less than the minimum value of the preset bubble disappearance time range, the addition speed of the aqueous acrylic resin is determined to be the second addition speed and the weight of the polyether-modified organic silicon compound is determined to be the second weight.

[0079] In the embodiment of the present invention, the minimum value of the preset bubble disappearance time range is four-fifths of the average bubble disappearance time of the dispersion prepared by shaking under the same preparation conditions several times, and the maximum value of the preset bubble disappearance time range is the average bubble disappearance time of the dispersion prepared by shaking under the same preparation conditions several times. The original addition rate is the average addition rate of the waterborne acrylic resin when the same preparation conditions are used several times, and the original weight is the average addition weight of the polyether-modified silicone compound when the same preparation conditions are used several times. The first addition rate is four-fifths of the original addition rate, the second addition rate is six-fifths of the original addition rate, the first weight is four-fifths of the original weight, and the second weight is six-fifths of the original weight. The same preparation conditions include but are not limited to "same raw material ratio, same preparation environment (such as temperature and humidity), and same preparation parameters (such as stirring time and raw material addition rate)", but the above values ​​are not limited to these. Those skilled in the art can also adjust the values ​​according to actual needs.

[0080] The present invention dynamically adjusts the addition rate of the water-based acrylic resin and the weight of the polyether-modified organic silicon compound according to the bubble disappearance time after shaking the dispersion liquid, and can accurately control the performance of the product. For example, if the bubble disappearance time is greater than the maximum value of a preset range, it indicates that the current dispersion state may cause certain performance deficiencies of the product. At this time, a first addition rate and a first weight are adopted. When the bubble disappearance time is within the preset range, the original addition rate and weight are maintained to ensure the consistency of product quality. When the bubble disappearance time deviates from the range, the parameters are reasonably adjusted to stabilize the product quality within an acceptable range again, reducing the product quality difference caused by fluctuations in the production process. According to the simple and easy to measure bubble disappearance time, the water-based acrylic resin addition rate and the polyether-modified organic silicon compound weight that should be adopted are quickly determined, thereby avoiding blind attempts and repeated experiments and improving production efficiency. The above method improves the accuracy of the control of the preparation process of the bullet rain agent coating and thereby improves the rapid hydrophobicity of the prepared bullet rain agent coating.

[0081] Specifically, in step S4, when determining the spraying distance and spraying pressure of the mixed solution, the spraying distance and spraying pressure of the mixed solution are determined according to the addition rate of the water-based acrylic resin and the weight of the polyether-modified organic silicon compound;

[0082] When the addition speed of the water-based acrylic resin is greater than a preset addition speed and the weight of the polyether-modified organosilicon compound is greater than a preset weight, determining the spraying distance of the mixed solution to be a first spraying distance and determining the spraying pressure of the mixed solution to be a first spraying pressure;

[0083] When the addition rate of the water-based acrylic resin is less than or equal to the preset addition rate or the weight of the polyether-modified silicone compound is less than or equal to the preset weight, the spraying distance of the mixed solution is determined to be the second spraying distance and the spraying pressure of the mixed solution is determined to be the second spraying pressure.

[0084] In the embodiment of the present invention, the value range of the first spraying distance is set to 25cm-30cm, the value of the first spraying distance is preferably 28cm, the value range of the second spraying distance is set to 15cm-20cm, the value of the second spraying distance is preferably 18cm, the value range of the first spraying pressure is set to 0.4MPa-0.5MPa, the value of the first spraying pressure is preferably 0.45MPa, the value range of the second spraying pressure is set to 0.3MPa-0.4MPa, the value of the second spraying pressure is preferably 0.35MPa, the preset addition rate is the historical average value of the addition rate of the water-based acrylic resin, and the preset weight is the historical average value of the addition weight of the polyether-modified silicone compound, but the above values ​​are not limited thereto, and those skilled in the art can also adjust the values ​​according to actual needs.

[0085] The present invention determines the spraying distance and pressure based on the addition rate of water-based acrylic resin and the weight of polyether-modified silicone compound, and can accurately match the spraying parameters according to different raw material addition conditions. When the addition amount of both raw materials is greater than the preset value, a relatively large first spraying distance is used, which helps to evenly disperse the mixed solution in a larger range when the amount of raw materials is large, avoid the concentrated accumulation of paint caused by close distance and low pressure, and ensure the uniformity and quality of the coating. When the addition amount of raw materials is less than or equal to the preset value, a relatively small second spraying distance and a lower second spraying pressure are selected. In this way, when the amount of raw materials is small, it can be ensured that the paint can effectively cover the target surface, and avoid insufficient coverage caused by excessive dispersion of paint due to long distance and high pressure. The above method improves the accuracy of the control of the preparation process of the bullet rain agent coating and thereby improves the rapid hydrophobicity of the prepared bullet rain agent coating.

[0086] Specifically, in step S5, when determining whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drying agent, it is determined whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drying agent based on the comparison result of the coating curing time and the preset coating curing time range;

[0087] When the coating curing time is less than the minimum value of the preset coating curing time range, determining to adjust the minimum value of the preset bubble disappearance time range;

[0088] When the coating curing time is longer than a maximum value of a preset coating curing time range, determining to adjust the weight of the ammonia drier;

[0089] When the coating curing time is within the preset coating curing time range, it is determined that there is no need to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drying agent.

[0090] Specifically, when determining to adjust the minimum value of the preset bubble disappearance time range, it is determined to adjust the minimum value of the preset bubble disappearance time range with a first adjustment coefficient; when determining to adjust the weight of the ammonia drying agent, it is determined to adjust the weight of the ammonia drying agent with a second adjustment coefficient.

[0091] In the embodiment of the present invention, the minimum value of the preset coating curing time range is three-fifths of the average value of the coating curing time under several times the same preparation conditions, and the maximum value of the preset coating curing time range is six-fifths of the average value of the coating curing time under several times the same preparation conditions. The value range of the first adjustment coefficient is set to 1.04-1.21, and the value of the first adjustment coefficient is preferably 1.10. The value range of the second adjustment coefficient is set to 1.03-0.19, and the value of the second adjustment coefficient is preferably 1.08. The adjustment amount of the minimum value of the preset bubble disappearance time range is negatively correlated with the coating curing time, and the adjustment amount of the weight of the ammonia drying agent is positively correlated with the coating curing time, but the above values ​​are not limited to this, and those skilled in the art can also adjust the value according to actual needs.

[0092] The present invention specifically adjusts the minimum value of the preset bubble disappearance time range or the weight of the ammonia drying agent based on the comparison result between the coating curing time and the preset range. When the coating curing time is less than the minimum value of the preset range, it indicates that the curing process is too fast. At this time, the minimum value of the preset bubble disappearance time range is adjusted, and the weight of the polyether-modified silicone compound can be reduced by affecting the early bubble-related parameters. When the coating curing time is greater than the maximum value of the preset range, it indicates that the curing is too slow, which may affect the product performance. By adjusting the weight of the ammonia drying agent, the curing speed can be effectively controlled to ensure that the coating curing effect meets the requirements and avoid product defects caused by abnormal curing time, such as insufficient coating hardness, decreased adhesion and other problems, thereby ensuring the stability of product quality.

[0093] A fast-acting hydrophobic rain-repellent coating prepared according to the present invention is prepared according to the above-described preparation method, using intermediate values ​​of the raw materials: 9 parts of special fluorosilane-modified nano-sized titanium dioxide particles, 2 parts of nano-sized zirconium oxide particles, 29 parts of water-based acrylic resin, 2 parts of sodium polyacrylate dispersant, 0.8 parts of a polyether-modified organosilicon compound, 0.75 parts of an ammonia-based drier, and 57.5 parts of deionized water. The dispersion preparation, mixed solution preparation, and subsequent steps were all carried out strictly in accordance with the parameters in the invention.

[0094] The conventional method of preparing the rain-of-fire coating is to select the conventional preparation formula and process of the rain-of-fire coating, and use the common preparation method on the market as a reference.

[0095] Test method:

[0096] Static contact angle test: Using a contact angle meter, under the same environmental conditions (temperature 25°C, humidity 50%), the same volume (5μL) of deionized water was added to the surfaces of the two coatings respectively, and the static contact angle of water on the coating surface was measured. The larger the contact angle, the better the hydrophobicity of the coating. Measure 5 different positions on each coating, and take the average value as the static contact angle of the coating.

[0097] Dynamic contact angle test: Also under the above environmental conditions, by tilting the sample stage, a water droplet is made to roll on the coating surface, and the advancing angle and receding angle of the water droplet are measured. The smaller the difference between the advancing angle and the receding angle, the better the rolling performance of the coating, that is, the better the rapid hydrophobic performance. Each coating is tested 5 times and the average value is taken.

[0098] Water droplet sliding time test: Place a water droplet of a certain volume (10μL) on the coating surface, tilt the coating to a certain angle (30°), and record the time it takes for the water droplet to slide off the coating surface. The shorter the sliding time, the better the rapid hydrophobic performance of the coating. Repeat the test 10 times for each coating and take the average value.

[0099] Test results:

[0100]

[0101] The static contact angle of the coating prepared by the present invention reaches about 155°, which is much higher than the 130° of the ordinary rain-repellent coating. This shows that the surface of the coating of the present invention has stronger hydrophobicity, and water molecules tend to form spheres on its surface rather than spread out; the difference between the advancing angle and the receding angle of the coating of the present invention is only about 10°, which is smaller than the 25° of the ordinary rain-repellent coating. This shows that water droplets roll more smoothly on the surface of the coating of the present invention and have better rapid hydrophobic performance. The time for water droplets to slide off the coating of the present invention is only about 1.5 seconds, which is significantly shorter than the 3.5 seconds of the ordinary rain-repellent coating. This further proves that in actual applications, the coating of the present invention can make water droplets slide off faster, thereby achieving a rapid hydrophobic effect.

[0102] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A method for preparing a fast hydrophobic rain-repellent coating, characterized in that: include: 8-10 parts of nano-sized titanium dioxide particles modified with special fluorosilane, 1-3 parts of nano-sized zirconium oxide particles, 28-30 parts of water-based acrylic resin, 1-3 parts of sodium polyacrylate dispersant, 0.6-1 part of polyether-modified organosilicon compound, 0.6-0.9 parts of ammonia drier and 55-60 parts of deionized water are selected as the preparation raw materials; Deionized water, nano-sized titanium dioxide particles modified with special fluorosilane, nano-sized zirconium oxide particles, and a sodium polyacrylate dispersant are sequentially added to a stirring container and stirred to obtain a dispersion. Based on whether the rising trajectory of the bubbles is regular and the rising speed is stable during stirring, the time it takes for the bubbles to disappear after continuing stirring or shaking the dispersion is recorded. Adding a water-based acrylic resin, a polyether-modified organosilicon compound, and an ammonia-based drier to the dispersion in sequence and stirring to obtain a mixed solution, and determining the addition rate of the water-based acrylic resin and the weight of the polyether-modified organosilicon compound by recording the time it takes for bubbles to disappear after shaking the dispersion; Determining the spraying distance and spraying pressure of the mixed solution based on the addition rate of the water-based acrylic resin and the weight of the polyether-modified organosilicon compound; After spraying is completed, the object is placed in a ventilated environment to allow the coating to cure, thereby obtaining a rain-repellent coating with rapid hydrophobicity. Based on the coating curing time, it is determined whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia-based drying agent. If the bubble rising trajectory is irregular or the rising speed is unstable, continue stirring. If the bubble rising trajectory is regular and the rising speed is stable, record the time it takes for the bubbles to disappear after shaking the dispersion. Determining whether the rising trajectory of bubbles during stirring is regular includes: A high-speed camera is used to obtain image data of the stirring process of the dispersion in the stirring container; Grayscale the captured image and convert the color image into a grayscale image; An image recognition algorithm is used to identify the position and outline of each bubble, and then a tracking algorithm based on feature point matching is used to record the bubble's trajectory. Calculate the curvature and direction change rate of each bubble's trajectory. If the curvature and direction change rate of the bubble are both within a preset range within a preset time period, determine the bubble's rising trajectory rule. Determining whether the rising speed of bubbles during stirring is stable includes: After the image acquisition is completed, a vertical monitoring area is delineated in the image according to the size and shape of the mixing container. The monitoring area covers the path of the rising bubbles. Determine the vertical coordinates of the bubble in the monitoring area through the identified bubble position and contour information; According to the vertical coordinate changes of the bubble in the continuous multi-frame images and the shooting frame rate, the rising distance of the bubble in unit time is calculated to obtain the rising speed; Calculate the average value of the bubble's rising speed over a preset time period, then compare the deviation of each calculated rising speed with the average value. If each deviation is within a preset speed fluctuation threshold, the bubble's rising speed is determined to be stable. Determine the addition rate of the waterborne acrylic resin and the weight of the polyether-modified silicone compound including: If the bubble disappearance time recorded after shaking the dispersion is greater than a maximum value of a preset bubble disappearance time range, determining that the addition rate of the water-based acrylic resin is a first addition rate and the weight of the polyether-modified organosilicon compound is a first weight; If the bubble disappearance time recorded after shaking the dispersion is within the preset bubble disappearance time range, the addition rate of the waterborne acrylic resin is determined to be the original addition rate and the weight of the polyether-modified organosilicon compound is determined to be the original weight; If the bubble disappearance time recorded after shaking the dispersion is less than a minimum value of a preset bubble disappearance time range, determining that the addition rate of the water-based acrylic resin is a second addition rate and the weight of the polyether-modified organosilicon compound is a second weight; Determining the spraying distance and spraying pressure of the mixed solution includes: If the addition speed of the water-based acrylic resin is greater than a preset addition speed and the weight of the polyether-modified organosilicon compound is greater than a preset weight, determining the spraying distance of the mixed solution to be a first spraying distance and determining the spraying pressure of the mixed solution to be a first spraying pressure; If the addition rate of the water-based acrylic resin is less than or equal to the preset addition rate or the weight of the polyether-modified organosilicon compound is less than or equal to the preset weight, determining the spraying distance of the mixed solution to be the second spraying distance and determining the spraying pressure of the mixed solution to be the second spraying pressure; Determining whether to adjust the minimum value of the preset bubble disappearance time range and the weight of the ammonia drier includes: If the coating curing time is less than the minimum value of the preset coating curing time range, determining to adjust the minimum value of the preset bubble disappearance time range; If the coating curing time is longer than a maximum value of a preset coating curing time range, it is determined that the weight of the ammonia drier is adjusted.

2. The method for preparing a fast hydrophobic rain-repellent coating according to claim 1, characterized in that: Determine the time it takes for bubbles to disappear after continuing to stir or record the time it takes to shake the dispersion: If the rising trajectory of the bubbles during stirring is regular and the rising speed is stable, determine and record the time it takes for the bubbles to disappear after shaking the dispersion; If the rising trajectory of the bubbles is irregular or the rising speed is unstable during stirring, continue stirring.

3. The method for preparing a fast hydrophobic rain-repellent coating according to claim 2, characterized in that: The preset change range of the curvature of the bubble within the preset time length is determined according to the change range of the curvature of the bubble within several preset time lengths, and the preset change range of the direction change rate of the bubble within the preset time length is determined according to the change range of the direction change rate of the bubble within several preset time lengths.

4. The method for preparing a fast hydrophobic rain-repellent coating according to claim 3, characterized in that: The preset speed fluctuation threshold range is determined according to the maximum value of the bubble rising speed within a plurality of preset time periods.

5. The method for preparing a fast hydrophobic rain-repellent coating according to claim 4, characterized in that: The adjustment amount of the minimum value of the preset bubble disappearance time range is negatively correlated with the coating curing time, and the adjustment amount of the weight of the ammonia drying agent is positively correlated with the coating curing time.

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