Processing method of anti-doodling coating and related processing system
By using a specific ratio of weather-resistant acrylic polymer resin and modified silicone resin in anti-graffiti coatings, a low surface energy protective layer is constructed, which solves the problems of insufficient water and oil repellency and solvent resistance in existing coatings. This achieves efficient removal of graffiti and long-term stability of the coating, making it suitable for a variety of substrates and scenarios.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-12
- Publication Date
- 2026-04-07
AI Technical Summary
Existing anti-graffiti coatings are inadequate in terms of water and oil repellency, solvent resistance, and primer compatibility, making it difficult to effectively control graffiti on urban public facilities and buildings.
Based on weather-resistant acrylic polymer resin and modified silicone resin, the mass ratio is controlled at 1:1.2-1:2.5, with the modified silicone resin accounting for no less than 30% of the mass. By introducing epoxy groups for modification, and in combination with hydrophobic and oleophobic modifiers and gasoline thinner, a protective layer with low surface energy and high slip properties is constructed to ensure the adhesion and wear resistance of the coating on a variety of substrates.
It makes it difficult for graffiti to adhere, eliminates the need for strong solvents when removing graffiti, reduces cleaning costs, extends the service life of the substrate, adapts to outdoor environments, and improves the overall performance and construction quality of the coating.
Smart Images
Figure CN121801462A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of anti-graffiti coating production and processing technology, specifically to an anti-graffiti coating processing method and related processing system. Background Technology
[0002] The "urban eyesores" of graffiti and illegal posting of small advertisements in public places have become a social nuisance. Relevant departments have to spend a lot of manpower and resources to clean them up repeatedly, but it is difficult to eradicate them completely.
[0003] Among the existing coatings used to control this problem, polyurethane products have defects such as poor water and oil repellency, low surface tension leading to poor graffiti removal effect, and limited solvent resistance; although silicone coatings have improved some properties, they still have shortcomings in terms of primer adaptability and outdoor use properties.
[0004] In summary, existing anti-graffiti coatings cannot meet the needs of effectively preventing and controlling "urban blight" in various scenarios such as urban public facilities and buildings. Summary of the Invention
[0005] This application provides a processing method and related processing system for anti-graffiti coatings, which helps to improve the graffiti removal effect of anti-graffiti coatings.
[0006] In a first aspect, embodiments of this application provide a method for processing anti-graffiti coating, including: A core base material is prepared, comprising a weather-resistant acrylate polymer resin and a modified silicone resin. In the core base material, the modified silicone resin accounts for no less than 30% by mass, and the mass ratio of the weather-resistant acrylate polymer resin to the modified silicone resin is 1:1.2-1:2.5. The modified silicone resin is prepared by introducing epoxy groups into the molecular chain of the silicone resin for modification. The modified silicone resin has a number-average molecular weight of 30,000-60,000 g / mol and an epoxy value of 0.05-0.12 eq / 100g. The core base material is put into a mixing device and stirred for 30-60 minutes at 25-35℃ and 500-800 r / min to obtain a mixed base material; Add a hydrophobic and oleophobic modifier to the mixed base material, and continue stirring for 40-80 minutes at 30-40℃ and 600-900 r / min to obtain a modified mixed base material. The amount of hydrophobic and oleophobic modifier added is 5%-10% of the mass of the mixed base material. Add gasoline thinner for viscosity adjustment to the modified base mixture to obtain a mixture with viscosity that meets the application parameters; filter the obtained mixture with viscosity that meets the application parameters through a 100-150 mesh filter to remove mechanical impurities and flocculent matter from the mixture to obtain an anti-graffiti coating.
[0007] Optionally, the weather-resistant acrylate polymer resin is a methyl methacrylate-butyl acrylate copolymer with a number-average molecular weight of 50,000-80,000 g / mol and a glass transition temperature of -10℃ to 20℃.
[0008] Optionally, the methyl methacrylate-butyl acrylate copolymer in the core base material is pretreated. The pretreatment includes: vacuum drying the methyl methacrylate-butyl acrylate copolymer at 60-80°C for 2-4 hours with a vacuum degree of -0.08 to -0.1 MPa to remove moisture and volatile impurities.
[0009] Optionally, the hydrophobic and oleophobic modifier is a fluorinated silane coupling agent.
[0010] Optionally, the fluorinated silane coupling agent may be of type KH-560 or KH-570.
[0011] Optionally, the amount of gasoline diluent added shall not exceed 20% of the mass of the mixture, and the solid content of the material after viscosity adjustment shall not be less than 30%.
[0012] Optionally, the mixing equipment is a double planetary mixer, and a wall scraping process is performed every 10-15 minutes during the mixing process. The wall scraping process is used to scrape off the material adhering to the inner wall of the mixing equipment.
[0013] Optionally, the hydrophobic and oleophobic modifier includes a fluorosilane coupling agent; the hydrophobic and oleophobic modifier is added to the mixed base material by dripping, with the fluorosilane coupling agent being added to the mixed base material at a rate of 1-3 ml / min, and no stirring is performed during the dripping process.
[0014] Optionally, protective nitrogen gas is continuously introduced during the mixing process to obtain the modified mixed base material, wherein the nitrogen gas flow rate is 0.5-1 L / min.
[0015] Optionally, the gasoline diluent needs to be dehydrated by molecular sieve before being added, wherein the water content of the dehydrated gasoline is not higher than 0.05%.
[0016] Optionally, the modified organosilicon resin in the core base material may account for, for example, 35%-50% by mass.
[0017] Optionally, the mass ratio of the weather-resistant acrylate polymer resin to the modified silicone resin may be, for example, 1:1.5 to 1:2.2.
[0018] Optionally, the number-average molecular weight of the methyl methacrylate-butyl acrylate copolymer may be, for example, 60,000-75,000 g / mol.
[0019] Optionally, the glass transition temperature of the methyl methacrylate-butyl acrylate copolymer can be, for example, 0°C to 15°C.
[0020] Optionally, the epoxy value of the modified silicone resin may be, for example, 0.07-0.10 eq / 100g.
[0021] Optionally, the number average molecular weight of the modified silicone resin can be, for example, 35,000-55,000 g / mol.
[0022] Optionally, the preparation process of the modified organosilicon resin may include: mixing organosilicon resin and epichlorohydrin at a mass ratio of 100:10-13, adding 0.8%-1.2% of boron trifluoride diethyl ether by mass of the organosilicon resin as a catalyst, reacting at 75-85℃ for 2.5-3.5 hours, and obtaining the modified organosilicon resin by removing unreacted epichlorohydrin through vacuum distillation.
[0023] Optionally, the stirring temperature of the core base material can be, for example, 28-32°C.
[0024] Optionally, the stirring speed of the core base material can be, for example, 600-750 r / min.
[0025] Optionally, the mixing time for the core base material can be, for example, 40-50 minutes.
[0026] Optionally, the amount of hydrophobic and oleophobic modifier added may be, for example, 6%-9% of the mass of the mixed base material.
[0027] Optionally, the stirring temperature after adding the hydrophobic and oleophobic modifier can be, for example, 32-38℃.
[0028] Optionally, the stirring speed after adding the hydrophobic and oleophobic modifier can be, for example, 700-850 r / min.
[0029] Optionally, the stirring time after adding the hydrophobic and oleophobic modifier can be, for example, 50-70 minutes.
[0030] Optionally, the viscosity of the viscosity-adjusted material, measured at 25°C using the Forecast-4 cup method, can be, for example, 15-22 s.
[0031] Optionally, the amount of gasoline thinner added may be, for example, 10%-18% of the mass of the modified blend base.
[0032] Optionally, the solids content of the modified blend can be, for example, 35%-45%.
[0033] Optionally, the mesh size of the filter can be, for example, 120-140 mesh.
[0034] Optionally, the surface drying time of the anti-graffiti coating may be, for example, 30-40 minutes. This can be measured according to GB6753.2-86 standard, at a test temperature of 25±2℃ and a relative humidity of 40%~70%.
[0035] Optionally, the peel strength of the adhesive tape for the anti-graffiti coating may be, for example, 0 N / cm, as determined according to GB / T 2792-2014.
[0036] Optionally, the water repellency of the anti-graffiti coating may be, for example, θav≥105°, θmin≥95°, reaching HC1 level, as determined, for example, according to the DLT864-2004 standard.
[0037] The second aspect of this application provides an anti-graffiti coating processing system, which can be used to implement some or all of the steps of the anti-graffiti coating processing method of the embodiments of this application.
[0038] For example, an anti-graffiti paint application system may include: Core base material proportioning device, material conveying device, mixing equipment, feeding device, and filter screen; A core base material proportioning device is used to prepare a core base material, wherein the core base material comprises a weather-resistant acrylate polymer resin and a modified organosilicon resin. In the core base material, the modified organosilicon resin accounts for no less than 30% by mass, and the mass ratio of the weather-resistant acrylate polymer resin to the modified organosilicon resin is 1:1.2-1:2.5. The modified organosilicon resin is prepared by introducing epoxy groups into the molecular chain of the organosilicon resin for modification. The number-average molecular weight of the modified organosilicon resin is 30,000-60,000 g / mol, and the epoxy value is 0.05-0.12 eq / 100g. A material conveying device is used to put the core base material into a mixing device and mix it for 30-60 minutes at a temperature of 25-35°C and a speed of 500-800 r / min to obtain a mixed base material. A feeding device is used to add a hydrophobic and oleophobic modifier to the mixed base material, and to continue stirring for 40-80 minutes at 30-40℃ and 600-900 r / min to obtain a modified mixed base material. The amount of hydrophobic and oleophobic modifier added is 5%-10% of the mass of the mixed base material. The feeding device is also used to add gasoline diluent used for viscosity adjustment to the modified mixed base material to obtain a mixed material with viscosity that meets the construction parameter conditions; The material conveying device is also used to filter the mixture with viscosity that meets the construction parameters through a 100-150 mesh filter screen to remove mechanical impurities and flocculent matter from the mixture in order to obtain anti-graffiti coating.
[0039] As can be seen, in the technical solution of this application embodiment, based on weather-resistant acrylate polymer resin and modified organosilicon resin, the mass ratio of the two is controlled at 1:1.2-1:2.5, and the mass proportion of modified organosilicon resin is not less than 30%. With its specific molecular structure design, the number average molecular weight is 30,000-60,000 g / mol, and the epoxy value is 0.05-0.12 eq / 100g. The introduction of epoxy groups not only improves the resin crosslinking density and constructs a dense and stable paint film structure, but also improves the compatibility of the two resins, avoids layering and precipitation, and lays the foundation for comprehensive performance. At the same time, adding 5%-10% of the mixed base material with a hydrophobic and oleophobic modifier creates a synergistic effect with the high proportion of modified silicone resin, thereby constructing a protective layer with low surface energy and high slipperiness on the paint film surface. This makes it difficult for various graffiti materials such as water-based markers and oil-based spray paints to wet and adhere. Even if graffiti is generated, it can be easily removed by wiping or rinsing without the need for strong solvents, thus fundamentally solving the problem of graffiti removal and avoiding secondary damage to the substrate during the cleaning process. In terms of overall film performance, the weather resistance of acrylic polymer resins and the high and low temperature resistance and weather erosion resistance of modified silicone resins complement each other, enabling the coating to adapt to long-term outdoor use environments. It effectively resists the effects of natural factors such as ultraviolet radiation and temperature changes, and is less prone to cracking, chalking, and yellowing, maintaining stable anti-graffiti performance over the long term. Furthermore, precise stirring control within a temperature range of 25-40℃, a rotation speed of 500-900 rpm, and a stirring time of 30-80 minutes ensures that all components are fully dispersed and react. Combined with filtration through a 100-150 mesh screen to remove impurities, this not only improves the adhesion of the paint film to various substrates such as concrete, metal, and plastic, but also enhances wear and scratch resistance. The viscosity adjustment using gasoline thinner allows for application through various methods such as spraying, brushing, and rolling, ensuring construction quality and aesthetic appearance. This coating is widely applicable to public facilities, building exteriors, and transportation vehicles, significantly reducing graffiti removal and substrate maintenance costs, and significantly extending the service life of the substrate, combining practicality and economy. Attached Figure Description
[0040] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0041] Figure 1 This is a schematic flowchart of an anti-graffiti coating processing method provided in an embodiment of this application; Figure 2 This is a schematic diagram of the architecture of an anti-graffiti coating processing system provided in an embodiment of this application. Detailed Implementation
[0042] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0043] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to some related drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.
[0044] See Figure 1 , Figure 1 This is a flowchart illustrating a method for processing anti-graffiti paint according to an embodiment of this application. The method includes: 101. Preparation of a core base material, wherein the core base material comprises a weather-resistant acrylate polymer resin and a modified organosilicon resin, wherein the modified organosilicon resin accounts for no less than 30% by mass in the core base material, and the mass ratio of the weather-resistant acrylate polymer resin to the modified organosilicon resin is 1:1.2-1:2.5; the modified organosilicon resin is prepared by introducing epoxy groups into the molecular chain of the organosilicon resin for modification, wherein the number average molecular weight of the modified organosilicon resin is 30000-60000 g / mol, and the epoxy value is 0.05-0.12 eq / 100g.
[0045] It is understandable that modified organosilicon resins obtained by modifying epoxy groups can also be called epoxy-modified organosilicon resins.
[0046] 102. The core base material is put into a mixing device and stirred for 30-60 minutes at 25-35℃ and 500-800 r / min to obtain a mixed base material.
[0047] 103. Add a hydrophobic and oleophobic modifier to the mixed base material, and continue stirring for 40-80 minutes at 30-40℃ and 600-900 r / min to obtain a modified mixed base material. The amount of hydrophobic and oleophobic modifier added is 5%-10% of the mass of the mixed base material.
[0048] 104. Add gasoline thinner for viscosity adjustment to the modified mixture to obtain a mixture with viscosity that meets the construction parameters; filter the obtained mixture with viscosity that meets the construction parameters through a 100-150 mesh filter to remove mechanical impurities and flocculent matter from the mixture to obtain an anti-graffiti coating.
[0049] Optionally, the weather-resistant acrylic polymer resin is a methyl methacrylate-butyl acrylate copolymer with a number-average molecular weight of 50,000-80,000 g / mol and a glass transition temperature of -10℃ to 20℃.
[0050] Optionally, the methyl methacrylate-butyl acrylate copolymer in the core base material is pretreated. The pretreatment includes: vacuum drying the methyl methacrylate-butyl acrylate copolymer at 60-80°C for 2-4 hours with a vacuum degree of -0.08 to -0.1 MPa to remove moisture and volatile impurities.
[0051] Furthermore, the core base material can also contain nano-level modified fillers (such as silica and titanium dioxide nanoparticles, with an addition amount of 3%-8% of the core base material mass). The nano-level modified fillers and the resin system form a synergistic effect, which is beneficial to improving the hardness, wear resistance (which can be reduced to ≤0.1g) and anti-graffiti durability of the coating.
[0052] Optionally, the hydrophobic and oleophobic modifier is a fluorinated silane coupling agent.
[0053] Optionally, the fluorinated silane coupling agent may be of type KH-560 or KH-570.
[0054] Optionally, the amount of gasoline diluent added shall not exceed 20% of the mass of the mixture, and the solid content of the material after viscosity adjustment shall not be less than 30%.
[0055] Optionally, the mixing equipment is a double planetary mixer, and a wall scraping process is performed every 10-15 minutes during the mixing process. The wall scraping process is used to scrape off the material adhering to the inner wall of the mixing equipment.
[0056] Optionally, the hydrophobic and oleophobic modifier includes a fluorosilane coupling agent; the hydrophobic and oleophobic modifier is added to the mixed base material by dripping, with the fluorosilane coupling agent being added to the mixed base material at a rate of 1-3 ml / min, and no stirring is performed during the dripping process.
[0057] Optionally, protective nitrogen gas is continuously introduced during the mixing process to obtain the modified mixed base material, wherein the nitrogen gas flow rate is 0.5-1 L / min.
[0058] Optionally, the gasoline diluent needs to be dehydrated by molecular sieve before being added, wherein the water content of the dehydrated gasoline is not higher than 0.05%.
[0059] Optionally, the modified organosilicon resin in the core base material may account for, for example, 35%-50% by mass.
[0060] Optionally, the mass ratio of the weather-resistant acrylate polymer resin to the modified silicone resin may be, for example, 1:1.5 to 1:2.2.
[0061] Optionally, the number-average molecular weight of the methyl methacrylate-butyl acrylate copolymer may be, for example, 60,000-75,000 g / mol.
[0062] Optionally, the glass transition temperature of the methyl methacrylate-butyl acrylate copolymer can be, for example, 0°C to 15°C.
[0063] Optionally, the epoxy value of the modified silicone resin may be, for example, 0.07-0.10 eq / 100g.
[0064] Optionally, the number average molecular weight of the modified silicone resin can be, for example, 35,000-55,000 g / mol.
[0065] Optionally, the preparation process of the modified organosilicon resin may include: mixing organosilicon resin and epichlorohydrin at a mass ratio of 100:10-13, adding 0.8%-1.2% of boron trifluoride diethyl ether by mass of the organosilicon resin as a catalyst, reacting at 75-85℃ for 2.5-3.5 hours, and obtaining the modified organosilicon resin by removing unreacted epichlorohydrin through vacuum distillation.
[0066] Optionally, the stirring temperature of the core base material can be, for example, 28-32°C.
[0067] Optionally, the stirring speed of the core base material can be, for example, 600-750 r / min.
[0068] Optionally, the mixing time for the core base material can be, for example, 40-50 minutes.
[0069] Optionally, the amount of hydrophobic and oleophobic modifier added may be, for example, 6%-9% of the mass of the mixed base material.
[0070] Optionally, the stirring temperature after adding the hydrophobic and oleophobic modifier can be, for example, 32-38℃.
[0071] Optionally, the stirring speed after adding the hydrophobic and oleophobic modifier can be, for example, 700-850 r / min.
[0072] Optionally, the stirring time after adding the hydrophobic and oleophobic modifier can be, for example, 50-70 minutes.
[0073] Optionally, the viscosity of the viscosity-adjusted material, measured at 25°C using the Forecast-4 cup method, can be, for example, 15-22 s.
[0074] Optionally, the amount of gasoline thinner added may be, for example, 10%-18% of the mass of the modified blend base.
[0075] Optionally, the solids content of the modified blend can be, for example, 35%-45%.
[0076] Optionally, the mesh size of the filter can be, for example, 120-140 mesh.
[0077] Optionally, the surface drying time of the anti-graffiti coating may be, for example, 30-40 minutes. This can be measured according to GB6753.2-86 standard, at a test temperature of 25±2℃ and a relative humidity of 40%~70%.
[0078] Optionally, the peel strength of the adhesive tape for the anti-graffiti coating may be, for example, 0 N / cm, as determined according to GB / T 2792-2014.
[0079] Optionally, the water repellency of the anti-graffiti coating may be, for example, θav≥105°, θmin≥95°, reaching HC1 level, as determined, for example, according to the DLT864-2004 standard.
[0080] Optionally, in some possible implementations, the preparation of the core base material may include: Weigh weather-resistant acrylate polymer resin (such as methyl methacrylate-butyl acrylate copolymer, number average molecular weight 60000-75000 g / mol) and epoxy-modified silicone resin (such as epoxy value 0.07-0.10 eq / 100g) at a mass ratio of 1:1.5-1:2.2, and add them to the reactor; add 0.2%-0.5% of dibutyltin dilaurate as a prepolymer catalyst and 0.1%-0.3% of antioxidant 1010 (to prevent high-temperature oxidation) of the total resin mass.
[0081] Close the reactor and purge the air inside with nitrogen (nitrogen flow rate 1-1.5 L / min, purging time 15-20 minutes). After purging, start the agitator in the reactor at 400-500 rpm. Gradually raise the reactor temperature to 85-95°C and maintain the temperature for 2-3 hours until the viscosity reaches 25-30 s (viscosity can be tested using the 25°C Ford cup method). Lower the reactor temperature to 50-60°C and let it stand for 30-40 minutes to obtain the prepolymer resin base material.
[0082] Weigh out 6%-9% of the fluorosilane coupling agent by mass of the prepolymer resin base, dilute the fluorosilane coupling agent with anhydrous ethanol to obtain a fluorosilane coupling agent solution with a mass fraction of 50%-55%, and stir the fluorosilane coupling agent solution evenly.
[0083] Maintain the reactor temperature at 50-60℃, adjust the stirring speed of the stirring device in the reactor to 600-700 r / min, and add the fluorinated silane coupling agent solution dropwise to the prepolymer resin base at a rate of 2-3 ml / min. The dropwise addition of the fluorinated silane coupling agent solution shall continue for 1-1.5 hours, and nitrogen gas shall be introduced into the reactor for protection throughout the process (flow rate 0.8-1 L / min).
[0084] After the addition is complete, heat the reactor to 70-80℃ and continue stirring for 3-4 hours to ensure that the fluorinated groups are fully grafted onto the active sites on the prepolymer resin molecular chain. For example, the intensity of the fluorine characteristic peak can be detected by infrared spectroscopy; when the peak intensity tends to stabilize, it is determined that the grafting is complete.
[0085] Cool the reactor to room temperature, add an appropriate amount of gasoline thinner to adjust the viscosity to 15-22s, and then filter out impurities through a 120-140 mesh filter to obtain the core base material for later use.
[0086] It is understandable that by improving resin compatibility through the prepolymerization stage and precisely introducing functional groups during the grafting stage in the preparation of core base materials, the hydrophobic contact angle of the coating can be increased to ≥110°, the anti-graffiti durability can be improved by 50% compared with the traditional one-step method, and the aging resistance life is expected to be extended to more than 10 years.
[0087] As can be seen, in the technical solution of this application embodiment, based on weather-resistant acrylate polymer resin and modified organosilicon resin, the mass ratio of the two is controlled at 1:1.2-1:2.5, and the mass proportion of modified organosilicon resin is not less than 30%. With its specific molecular structure design, the number average molecular weight is 30,000-60,000 g / mol, and the epoxy value is 0.05-0.12 eq / 100g. The introduction of epoxy groups not only improves the resin crosslinking density and constructs a dense and stable paint film structure, but also improves the compatibility of the two resins, avoids layering and precipitation, and lays the foundation for comprehensive performance. At the same time, adding 5%-10% of the mixed base material with a hydrophobic and oleophobic modifier creates a synergistic effect with the high proportion of modified silicone resin, thereby constructing a protective layer with low surface energy and high slipperiness on the paint film surface. This makes it difficult for various graffiti materials such as water-based markers and oil-based spray paints to wet and adhere. Even if graffiti is generated, it can be easily removed by wiping or rinsing without the need for strong solvents, thus fundamentally solving the problem of graffiti removal and avoiding secondary damage to the substrate during the cleaning process. In terms of overall film performance, the weather resistance of acrylic polymer resins and the high and low temperature resistance and weather erosion resistance of modified silicone resins complement each other, enabling the coating to adapt to long-term outdoor use environments. It effectively resists the effects of natural factors such as ultraviolet radiation and temperature changes, and is less prone to cracking, chalking, and yellowing, maintaining stable anti-graffiti performance over the long term. Furthermore, precise stirring control within a temperature range of 25-40℃, a rotation speed of 500-900 rpm, and a stirring time of 30-80 minutes ensures that all components are fully dispersed and react. Combined with filtration through a 100-150 mesh screen to remove impurities, this not only improves the adhesion of the paint film to various substrates such as concrete, metal, and plastic, but also enhances wear and scratch resistance. The viscosity adjustment using gasoline thinner allows for application through various methods such as spraying, brushing, and rolling, ensuring construction quality and aesthetic appearance. This coating is widely applicable to public facilities, building exteriors, and transportation vehicles, significantly reducing graffiti removal and substrate maintenance costs, and significantly extending the service life of the substrate, combining practicality and economy.
[0088] Furthermore, when the number-average molecular weight of methyl methacrylate-butyl acrylate copolymer is 60,000-75,000 g / mol and the glass transition temperature is 0℃-15℃, combined with modified silicone resin with an epoxy value of 0.07-0.10 eq / 100g (of which, by mass, it accounts for 35%-50%), experimental tests show that the coating's weather resistance is improved by 30% compared to the undefined parameter group, and the adhesion reaches Grade 1 (measured according to GB / T 9274-1988 standard). After the resin is pretreated by vacuum drying at 60-80℃, the moisture content of the coating system is ≤0.03%, the bubble generation rate is reduced by 80%, and the batch stability is significantly improved.
[0089] In terms of process optimization, when a dual planetary mixer is used in conjunction with wall scraping every 10-15 minutes, the uniformity of raw material mixing reaches 98%; when modifiers are added dropwise under nitrogen protection (1-3 ml / min), the conversion rate of the modification reaction is increased to 5%, and by-products are reduced by 40%. Gasoline is dehydrated by molecular sieve (water content ≤0.05%) and added in stages, achieving viscosity control accuracy of ±0.3s, improving the smoothness of application by 50%, and avoiding problems such as sagging or uneven coating.
[0090] When the stirring temperature is 28-32℃ and the stirring speed is 600-750r / min, the solid content of the coating is stabilized at 35%-45%, with a batch deviation of ≤2%. After two-stage filtration with a 120-140 mesh filter, the particle size of impurities in the coating is ≤10μm, and the smoothness of the coating film is improved by 60%.
[0091] The product's performance has been experimentally verified, with hydrophobicity reaching θav≥105° and θmin≥95° (HC1 grade), adhesive tape peel strength of 0N / cm, surface drying time of 30-40min (25±2℃), and abrasion resistance of ≤0.15g (GB / T 1689-1998). Compared with the basic solution, the key indicators are improved by 20%-40%, making it suitable for construction in multiple scenarios, and the expected protective life is extended to more than 8 years.
[0092] See Figure 2 This application also provides an anti-graffiti coating processing system, which can be used to implement some or all of the steps of the anti-graffiti coating processing method of this application.
[0093] For example, an anti-graffiti coating processing system may include: a core base material proportioning device 210, a material conveying device 220, a mixing device 230, a feeding device 240, and a filter screen 250.
[0094] The core base material proportioning device 210 is used to prepare the core base material, wherein the core base material includes weather-resistant acrylate polymer resin and modified organosilicon resin. In the core base material, the mass proportion of modified organosilicon resin is not less than 30%, and the mass ratio of weather-resistant acrylate polymer resin to modified organosilicon resin is 1:1.2-1:2.5. The modified organosilicon resin is obtained by introducing epoxy groups into the molecular chain of organosilicon resin for modification. The number average molecular weight of the modified organosilicon resin is 30,000-60,000 g / mol, and the epoxy value is 0.05-0.12 eq / 100g. Material conveying device 220 is used to put the core base material into mixing equipment 230 and mix it for 30-60 minutes under the mixing conditions of 25-35℃ and 500-800r / min to obtain mixed base material; The feeding device 240 is used to add a hydrophobic and oleophobic modifier to the mixed base material, and continue stirring for 40-80 minutes at 30-40℃ and 600-900 r / min to obtain a modified mixed base material. The amount of the hydrophobic and oleophobic modifier added is 5%-10% of the mass of the mixed base material. The feeding device is also used to add gasoline diluent used for viscosity adjustment to the modified mixed base material to obtain a mixed material with viscosity that meets the construction parameter conditions; The material conveying device is also used to filter the mixture with viscosity that meets the construction parameters through a 100-150 mesh filter screen to remove mechanical impurities and flocculent matter from the mixture in order to obtain anti-graffiti coating.
[0095] Optionally, the weather-resistant acrylic polymer resin is a methyl methacrylate-butyl acrylate copolymer with a number-average molecular weight of 50,000-80,000 g / mol and a glass transition temperature of -10℃ to 20℃.
[0096] Optionally, the methyl methacrylate-butyl acrylate copolymer in the core base material is pretreated. The pretreatment includes: vacuum drying the methyl methacrylate-butyl acrylate copolymer at 60-80°C for 2-4 hours with a vacuum degree of -0.08 to -0.1 MPa to remove moisture and volatile impurities.
[0097] Furthermore, the core base material can also contain nano-level modified fillers (such as silica and titanium dioxide nanoparticles, with an addition amount of 3%-8% of the core base material mass). The nano-level modified fillers and the resin system form a synergistic effect, which is beneficial to improving the hardness, wear resistance (which can be reduced to ≤0.1g) and anti-graffiti durability of the coating.
[0098] Optionally, the hydrophobic and oleophobic modifier is a fluorinated silane coupling agent.
[0099] Optionally, the fluorinated silane coupling agent may be of type KH-560 or KH-570.
[0100] Optionally, the amount of gasoline diluent added shall not exceed 20% of the mass of the mixture, and the solid content of the material after viscosity adjustment shall not be less than 30%.
[0101] Optionally, the mixing equipment is a double planetary mixer, and a wall scraping process is performed every 10-15 minutes during the mixing process. The wall scraping process is used to scrape off the material adhering to the inner wall of the mixing equipment.
[0102] Optionally, the hydrophobic and oleophobic modifier includes a fluorosilane coupling agent; the hydrophobic and oleophobic modifier is added to the mixed base material by dripping, with the fluorosilane coupling agent being added to the mixed base material at a rate of 1-3 ml / min, and no stirring is performed during the dripping process.
[0103] Optionally, protective nitrogen gas is continuously introduced during the mixing process to obtain the modified mixed base material, wherein the nitrogen gas flow rate is 0.5-1 L / min.
[0104] Optionally, the gasoline diluent needs to be dehydrated by molecular sieve before being added, wherein the water content of the dehydrated gasoline is not higher than 0.05%.
[0105] Optionally, the modified organosilicon resin in the core base material may account for, for example, 35%-50% by mass.
[0106] Optionally, the mass ratio of the weather-resistant acrylate polymer resin to the modified silicone resin may be, for example, 1:1.5 to 1:2.2.
[0107] Optionally, the number-average molecular weight of the methyl methacrylate-butyl acrylate copolymer may be, for example, 60,000-75,000 g / mol.
[0108] Optionally, the glass transition temperature of the methyl methacrylate-butyl acrylate copolymer can be, for example, 0°C to 15°C.
[0109] Optionally, the epoxy value of the modified silicone resin may be, for example, 0.07-0.10 eq / 100g.
[0110] Optionally, the number average molecular weight of the modified silicone resin can be, for example, 35,000-55,000 g / mol.
[0111] Optionally, the preparation process of the modified organosilicon resin may include: mixing organosilicon resin and epichlorohydrin at a mass ratio of 100:10-13, adding 0.8%-1.2% of boron trifluoride diethyl ether by mass of the organosilicon resin as a catalyst, reacting at 75-85℃ for 2.5-3.5 hours, and obtaining the modified organosilicon resin by removing unreacted epichlorohydrin through vacuum distillation.
[0112] Optionally, the stirring temperature of the core base material can be, for example, 28-32°C.
[0113] Optionally, the stirring speed of the core base material can be, for example, 600-750 r / min.
[0114] Optionally, the mixing time for the core base material can be, for example, 40-50 minutes.
[0115] Optionally, the amount of hydrophobic and oleophobic modifier added may be, for example, 6%-9% of the mass of the mixed base material.
[0116] Optionally, the stirring temperature after adding the hydrophobic and oleophobic modifier can be, for example, 32-38℃.
[0117] Optionally, the stirring speed after adding the hydrophobic and oleophobic modifier can be, for example, 700-850 r / min.
[0118] Optionally, the stirring time after adding the hydrophobic and oleophobic modifier can be, for example, 50-70 minutes.
[0119] Optionally, the viscosity of the viscosity-adjusted material, measured at 25°C using the Forecast-4 cup method, can be, for example, 15-22 s.
[0120] Optionally, the amount of gasoline thinner added may be, for example, 10%-18% of the mass of the modified blend base.
[0121] Optionally, the solids content of the modified blend can be, for example, 35%-45%.
[0122] Optionally, the mesh size of the filter can be, for example, 120-140 mesh.
[0123] Optionally, the surface drying time of the anti-graffiti coating may be, for example, 30-40 minutes. This can be measured according to GB6753.2-86 standard, at a test temperature of 25±2℃ and a relative humidity of 40%~70%.
[0124] Optionally, the peel strength of the adhesive tape for the anti-graffiti coating may be, for example, 0 N / cm, as determined according to GB / T 2792-2014.
[0125] Optionally, the water repellency of the anti-graffiti coating may be, for example, θav≥105°, θmin≥95°, reaching HC1 level, as determined, for example, according to the DLT864-2004 standard.
[0126] Optionally, in some possible implementations, the preparation of the core base material may include: Weigh weather-resistant acrylate polymer resin (such as methyl methacrylate-butyl acrylate copolymer, number average molecular weight 60000-75000 g / mol) and epoxy-modified silicone resin (such as epoxy value 0.07-0.10 eq / 100g) at a mass ratio of 1:1.5-1:2.2, and add them to the reactor; add 0.2%-0.5% of dibutyltin dilaurate as a prepolymer catalyst and 0.1%-0.3% of antioxidant 1010 (to prevent high-temperature oxidation) of the total resin mass.
[0127] Close the reactor and purge the air inside with nitrogen (nitrogen flow rate 1-1.5 L / min, purging time 15-20 minutes). After purging, start the agitator in the reactor at 400-500 rpm. Gradually raise the reactor temperature to 85-95°C and maintain the temperature for 2-3 hours until the viscosity reaches 25-30 s (viscosity can be tested using the 25°C Ford cup method). Lower the reactor temperature to 50-60°C and let it stand for 30-40 minutes to obtain the prepolymer resin base material.
[0128] Weigh out 6%-9% of the fluorosilane coupling agent by mass of the prepolymer resin base, dilute the fluorosilane coupling agent with anhydrous ethanol to obtain a fluorosilane coupling agent solution with a mass fraction of 50%-55%, and stir the fluorosilane coupling agent solution evenly.
[0129] Maintain the reactor temperature at 50-60℃, adjust the stirring speed of the stirring device in the reactor to 600-700 r / min, and add the fluorinated silane coupling agent solution dropwise to the prepolymer resin base at a rate of 2-3 ml / min. The dropwise addition of the fluorinated silane coupling agent solution shall continue for 1-1.5 hours, and nitrogen gas shall be introduced into the reactor for protection throughout the process (flow rate 0.8-1 L / min).
[0130] After the addition is complete, heat the reactor to 70-80℃ and continue stirring for 3-4 hours to ensure that the fluorinated groups are fully grafted onto the active sites on the prepolymer resin molecular chain. For example, the intensity of the fluorine characteristic peak can be detected by infrared spectroscopy; when the peak intensity tends to stabilize, it is determined that the grafting is complete.
[0131] Cool the reactor to room temperature, add an appropriate amount of gasoline thinner to adjust the viscosity to 15-22s, and then filter out impurities through a 120-140 mesh filter to obtain the core base material for later use.
[0132] It is understandable that by improving resin compatibility through the prepolymerization stage and precisely introducing functional groups during the grafting stage in the preparation of core base materials, the hydrophobic contact angle of the coating can be increased to ≥110°, the anti-graffiti durability can be improved by 50% compared with the traditional one-step method, and the aging resistance life is expected to be extended to more than 10 years.
[0133] As can be seen, the system of this application includes a core base material proportioning device, a material conveying device, a stirring device, a feeding device, and a filter screen. The core base material proportioning device is based on weather-resistant acrylic polymer resin and modified organosilicon resin, controlling the mass ratio of the two to be 1:1.2-1:2.5, with the modified organosilicon resin accounting for no less than 30% of the mass. Combined with its specific molecular structure design, the number average molecular weight is 30,000-60,000 g / mol, and the epoxy value is 0.05-0.12 eq / 100g. The introduction of epoxy groups not only increases the resin crosslinking density, constructing a dense and stable paint film structure, but also improves the compatibility of the two resins, preventing stratification and laying the foundation for comprehensive performance. At the same time, adding 5%-10% of the mixed base material with a hydrophobic and oleophobic modifier creates a synergistic effect with the high proportion of modified silicone resin, thereby constructing a protective layer with low surface energy and high slipperiness on the paint film surface. This makes it difficult for various graffiti materials such as water-based markers and oil-based spray paints to wet and adhere. Even if graffiti is generated, it can be easily removed by wiping or rinsing without the need for strong solvents, thus fundamentally solving the problem of graffiti removal and avoiding secondary damage to the substrate during the cleaning process. In terms of overall film performance, the weather resistance of acrylic polymer resins and the high and low temperature resistance and weather erosion resistance of modified silicone resins complement each other, enabling the coating to adapt to long-term outdoor use environments. It effectively resists the effects of natural factors such as ultraviolet radiation and temperature changes, and is less prone to cracking, chalking, and yellowing, maintaining stable anti-graffiti performance over the long term. Furthermore, precise stirring control within a temperature range of 25-40℃, a rotation speed of 500-900 rpm, and a stirring time of 30-80 minutes ensures that all components are fully dispersed and react. Combined with filtration through a 100-150 mesh screen to remove impurities, this not only improves the adhesion of the paint film to various substrates such as concrete, metal, and plastic, but also enhances wear and scratch resistance. The viscosity adjustment using gasoline thinner allows for application through various methods such as spraying, brushing, and rolling, ensuring construction quality and aesthetic appearance. This coating is widely applicable to public facilities, building exteriors, and transportation vehicles, significantly reducing graffiti removal and substrate maintenance costs, and significantly extending the service life of the substrate, combining practicality and economy.
[0134] Furthermore, when the number-average molecular weight of methyl methacrylate-butyl acrylate copolymer is 60,000-75,000 g / mol and the glass transition temperature is 0℃-15℃, combined with modified silicone resin with an epoxy value of 0.07-0.10 eq / 100g (of which, by mass, it accounts for 35%-50%), experimental tests show that the coating's weather resistance is improved by 30% compared to the undefined parameter group, and the adhesion reaches Grade 1 (measured according to GB / T 9274-1988 standard). After the resin is pretreated by vacuum drying at 60-80℃, the moisture content of the coating system is ≤0.03%, the bubble generation rate is reduced by 80%, and the batch stability is significantly improved.
[0135] In terms of process optimization, when a dual planetary mixer is used in conjunction with wall scraping every 10-15 minutes, the uniformity of raw material mixing reaches 98%; when modifiers are added dropwise under nitrogen protection (1-3 ml / min), the conversion rate of the modification reaction is increased to 5%, and by-products are reduced by 40%. Gasoline is dehydrated by molecular sieve (water content ≤0.05%) and added in stages, achieving viscosity control accuracy of ±0.3s, improving the smoothness of application by 50%, and avoiding problems such as sagging or uneven coating.
[0136] When the stirring temperature is 28-32℃ and the stirring speed is 600-750r / min, the solid content of the coating is stabilized at 35%-45%, with a batch deviation of ≤2%. After two-stage filtration with a 120-140 mesh filter, the particle size of impurities in the coating is ≤10μm, and the smoothness of the coating film is improved by 60%.
[0137] The product's performance has been experimentally verified, with hydrophobicity reaching θav≥105° and θmin≥95° (HC1 grade), adhesive tape peel strength of 0N / cm, surface drying time of 30-40min (25±2℃), and abrasion resistance of ≤0.15g (GB / T 1689-1998). Compared with the basic solution, the key indicators are improved by 20%-40%, making it suitable for construction in multiple scenarios, and the expected protective life is extended to more than 8 years.
[0138] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be some changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A method for processing anti-graffiti paint, characterized in that, include: A core base material is prepared, comprising a weather-resistant acrylate polymer resin and a modified silicone resin. In the core base material, the modified silicone resin accounts for no less than 30% by mass, and the mass ratio of the weather-resistant acrylate polymer resin to the modified silicone resin is 1:1.2-1:2.
5. The modified silicone resin is prepared by introducing epoxy groups into the molecular chain of the silicone resin for modification. The modified silicone resin has a number-average molecular weight of 30,000-60,000 g / mol and an epoxy value of 0.05-0.12 eq / 100g. The core base material is put into a mixing device and stirred for 30-60 minutes at 25-35℃ and 500-800 r / min to obtain a mixed base material; Add a hydrophobic and oleophobic modifier to the mixed base material, and continue stirring for 40-80 minutes at 30-40℃ and 600-900 r / min to obtain a modified mixed base material. The amount of hydrophobic and oleophobic modifier added is 5%-10% of the mass of the mixed base material. Add gasoline thinner for viscosity adjustment to the modified base mixture to obtain a mixture with viscosity that meets the application parameters; filter the obtained mixture with viscosity that meets the application parameters through a 100-150 mesh filter to remove mechanical impurities and flocculent matter from the mixture to obtain an anti-graffiti coating.
2. The method according to claim 1, characterized in that, The weather-resistant acrylate polymer resin is a methyl methacrylate-butyl acrylate copolymer with a number-average molecular weight of 50,000-80,000 g / mol and a glass transition temperature of -10℃ to 20℃.
3. The method according to claim 2, characterized in that, The methyl methacrylate-butyl acrylate copolymer in the core base material is pretreated. The pretreatment includes: vacuum drying the methyl methacrylate-butyl acrylate copolymer at 60-80℃ for 2-4 hours with a vacuum degree of -0.08 to -0.1 MPa to remove moisture and volatile impurities.
4. The method according to any one of claims 1 to 3, characterized in that, The hydrophobic and oleophobic modifier is a fluorinated silane coupling agent.
5. The method according to any one of claims 1 to 4, characterized in that, The amount of gasoline diluent added shall not exceed 20% of the mass of the mixture, and the solid content of the material after viscosity adjustment shall not be less than 30%.
6. The method according to any one of claims 1 to 5, characterized in that, The mixing equipment is a double planetary mixer. During the mixing process, a wall scraping process is performed every 10-15 minutes to remove the material adhering to the inner wall of the mixing equipment.
7. The method according to any one of claims 1 to 6, characterized in that, The hydrophobic and oleophobic modifier includes a fluorosilane coupling agent; the hydrophobic and oleophobic modifier is added to the mixed base material by dripping, with the fluorosilane coupling agent being dripped into the mixed base material at a rate of 1-3 ml / min, and no stirring is performed during the dripping process.
8. The method according to claim 7, characterized in that, During the process of mixing to obtain the modified mixed base material, protective nitrogen gas is continuously introduced at a flow rate of 0.5-1 L / min.
9. The method according to any one of claims 1 to 9, characterized in that, The gasoline diluent must be dehydrated by molecular sieve before being added, and the water content of the dehydrated gasoline shall not exceed 0.05%.
10. A system for processing anti-graffiti paint, characterized in that, include: Core base material proportioning device, material conveying device, mixing equipment, feeding device, and filter screen; A core base material proportioning device is used to prepare a core base material, wherein the core base material comprises a weather-resistant acrylate polymer resin and a modified organosilicon resin. In the core base material, the modified organosilicon resin accounts for no less than 30% by mass, and the mass ratio of the weather-resistant acrylate polymer resin to the modified organosilicon resin is 1:1.2-1:2.
5. The modified organosilicon resin is prepared by introducing epoxy groups into the molecular chain of the organosilicon resin for modification. The number-average molecular weight of the modified organosilicon resin is 30,000-60,000 g / mol, and the epoxy value is 0.05-0.12 eq / 100g. A material conveying device is used to put the core base material into a mixing device and mix it for 30-60 minutes at a temperature of 25-35°C and a speed of 500-800 r / min to obtain a mixed base material. A feeding device is used to add a hydrophobic and oleophobic modifier to the mixed base material, and to continue stirring for 40-80 minutes at 30-40℃ and 600-900 r / min to obtain a modified mixed base material. The amount of hydrophobic and oleophobic modifier added is 5%-10% of the mass of the mixed base material. The feeding device is also used to add gasoline diluent used for viscosity adjustment to the modified mixed base material to obtain a mixed material with viscosity that meets the construction parameter conditions; The material conveying device is also used to filter the mixture with viscosity that meets the construction parameters through a 100-150 mesh filter screen to remove mechanical impurities and flocculent matter from the mixture in order to obtain anti-graffiti coating.