Wear-resistant PVC decorative film surface treatment process and equipment thereof

Abstract

The invention relates to the field of furniture surface coating, and discloses a wear-resistant PVC decorative film surface treatment process which comprises the following steps: S1, providing a PVC decorative film base material, and cleaning the base material; s2, performing plasma surface treatment on the base material; s3, preparing a coating solution; s4, the surface of the base material is evenly coated with the coating solution; s5, forming a microporous structure through a solvent exchange phase separation process; s6, the coating is subjected to UV curing treatment, and the wear-resistant antibacterial coating is formed; a coating solution in the step S3 comprises the following components in percentage by weight: 30%-40% of polyurethane; and 35%-45% of epoxy resin and a curing agent thereof. Polyvinyl alcohol is introduced as a hydrogen bond reinforcing agent, and the material can form a strong hydrogen bond with coating molecules in the curing process, so that the chemical stability and toughness of the coating are enhanced. The moisture resistance and the corrosion resistance of the coating are obviously improved.

Description

Technical Field

[0001] This invention relates to the field of furniture surface coating technology, specifically to a surface treatment process and equipment for wear-resistant PVC decorative film. Background Technology

[0002] In the furniture manufacturing and home decoration industries, PVC decorative film, as a lightweight, aesthetically pleasing, and easily processed surface material, is widely used in the coating process of substrates such as wall panels, cabinets, and furniture surfaces. Its main function is to provide a decorative effect while enhancing the substrate's wear resistance, stain resistance, and lifespan. Existing PVC decorative films typically achieve surface protection through methods such as hot pressing, vacuum forming, or coating with a transparent protective layer. However, in long-term use, traditional PVC decorative films still face several technical challenges:

[0003] First, insufficient abrasion resistance is one of the key issues affecting the lifespan of PVC decorative films. PVC material itself has limited mechanical strength, and even with a protective coating, it is still prone to scratches, wear, or peeling under long-term friction and abrasion. For example, frequently used surfaces such as cabinet doors and wall panels are often subjected to external friction, leading to a decrease in the gloss of the decorative film surface and even localized damage. This not only affects aesthetics but may also impact the durability of the substrate. Traditional methods to enhance abrasion resistance mainly include increasing coating thickness or adding abrasion-resistant fillers, but these methods often result in excessively thick film layers, affecting flexibility, and uneven filler dispersion may reduce coating transparency and adhesion.

[0004] Secondly, insufficient antibacterial and hygienic properties are also a significant challenge currently facing PVC decorative films. In environments such as kitchens and bathrooms, PVC decorative films easily accumulate oil, water stains, and bacteria, potentially becoming a breeding ground for microorganisms after prolonged use, thus affecting the hygiene of the indoor environment. Existing antibacterial technologies mainly rely on surface coating with antibacterial agents, but because antibacterial agents in ordinary protective layers are prone to dissolution or inactivation, their antibacterial effect is difficult to maintain for a long time. In addition, some antibacterial coatings, due to improper curing methods, may affect the flexibility and durability of the PVC film, further reducing its practical application value. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a surface treatment process and equipment for wear-resistant PVC decorative films, which solves the problems of easy scratching, insufficient antibacterial properties, and difficulty in removing stains from existing PVC decorative films.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a wear-resistant PVC decorative film surface treatment process, comprising the following steps:

[0007] S1. Provide a PVC decorative film substrate and clean the substrate;

[0008] S2. Perform plasma surface treatment on the substrate;

[0009] S3. Prepare the coating solution;

[0010] S4. Apply the coating solution evenly to the surface of the substrate;

[0011] S5. Microporous structures are formed through solvent exchange phase separation process;

[0012] S6. The coating is UV cured to form a wear-resistant and antibacterial coating.

[0013] Preferably, the coating solution in step S3 comprises the following components by weight percentage:

[0014] Polyurethane: 30%-40%;

[0015] Epoxy resin and its curing agent: 35%-45%;

[0016] Antibacterial functional groups: 15%-22%;

[0017] Hydrogen bond enhancer: 5%-10%;

[0018] Ionic bond stabilized antibacterial agent: 3%-8%;

[0019] Photocatalyst: 3%-7%;

[0020] Solvent: 10%-15%.

[0021] Preferably, in step S2, the plasma surface treatment uses Ar-O2 plasma with a treatment power of 50-80W and a treatment time of 30-60 seconds.

[0022] Preferably, the antibacterial functional group is a benzothiazole derivative, the hydrogen bond enhancer is polyvinyl alcohol, the ionic bond stabilizing antibacterial agent includes a silver ion and quaternary ammonium salt complex with a mixing ratio of 1:10 to 1:100, the photocatalyst is zinc oxide with a particle size of 50 nm, and the solvent is a mixed solvent of dimethylformamide and ethanol with a mixing ratio of 1:1 to 3:1.

[0023] Preferably, step S1 includes cleaning the substrate using deionized water, ethanol, or ultrasonic cleaning.

[0024] Preferably, the S4 step uses a spraying method, and the spraying parameters include a nozzle diameter of 0.2-1.5 mm, an air pressure of 0.1-0.4 MPa, and a spraying moving speed of 50-200 mm / s.

[0025] Preferably, the solvent exchange phase separation process includes:

[0026] S51. Immerse the coated film in ethanol;

[0027] S52 and N-methylpyrrolidone diffuse outwards, while ethanol enters the membrane, initiating phase separation.

[0028] S53. The polymer phase is enriched to form a continuous phase, while the solvent phase precipitates and forms micropores.

[0029] Preferably, in step S6, the wavelength of the UV curing light source is 365nm to 405nm.

[0030] Preferably, step S6 further includes heat treatment, subjecting the UV-cured coating to heat treatment within a temperature range of 50-120°C.

[0031] A surface treatment process equipment for wear-resistant PVC decorative film, comprising:

[0032] Ultrasonic cleaning machines are used to remove oil, dust, and particles from the surface of substrates through ultrasonic vibration.

[0033] A plasma surface treatment machine is used to activate the surface of PVC decorative film using Ar-O2 plasma.

[0034] Magnetic stirrer for uniformly mixing coating solutions;

[0035] A spraying machine is used to uniformly apply a coating solution to the surface of the substrate.

[0036] Solvent immersion tank is used to complete the solvent exchange phase separation process;

[0037] A UV curing machine is used to cure coatings with UV light, forming a wear-resistant and antibacterial coating.

[0038] Hot air circulating oven is used to heat coatings evenly by circulating hot air.

[0039] This invention provides a surface treatment process and equipment for wear-resistant PVC decorative film. It offers the following advantages:

[0040] 1. This invention introduces polyvinyl alcohol as a hydrogen bonding enhancer. This material can form strong hydrogen bonds with coating molecules during the curing process, thereby enhancing the chemical stability and toughness of the coating. This significantly improves the coating's moisture resistance and corrosion resistance, especially in humid or chemical environments, where the coating's stability is enhanced. This allows the coating to effectively cope not only with wear and tear during daily use but also with more complex and severe environmental challenges.

[0041] 2. This invention optimizes the fluidity and stability of the coating solution by mixing dimethylformamide and ethanol in a specific ratio. Through this innovative solvent system, the viscosity and evaporation rate of the coating are precisely controlled, resulting in a uniform coating effect and avoiding problems such as uneven coating or cracking.

[0042] 3. This invention adds a zinc oxide photocatalyst to the coating solution. This catalyst can initiate a photocatalytic reaction under ultraviolet light irradiation, achieving a self-cleaning function on the coating surface. Using this technology, the coating can degrade organic pollutants and bacterial metabolites when exposed to sunlight, resulting in anti-pollution and anti-aging effects. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the method steps of the present invention;

[0044] Figure 2 This is a schematic diagram of the processing steps of the device of the present invention. Detailed Implementation

[0045] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Please see the appendix Figure 1 - Appendix Figure 2 This invention provides a surface treatment process for wear-resistant PVC decorative film, including the following steps:

[0047] S1. Provide PVC decorative film substrate and clean the substrate;

[0048] Specifically, a PVC decorative film is first provided as the substrate. This PVC decorative film can be a commercially available standard decorative film, typically 0.1mm to 0.5mm thick, with appropriate specifications selected according to application requirements. To ensure uniform adhesion of the subsequent coating and enhance bonding strength, the substrate needs to be cleaned to remove any dust, oil, particles, or other contaminants that may be present on the surface. This step uses an ultrasonic cleaner. The cleaning solution for the ultrasonic cleaner can be deionized water, alcohol, or other suitable organic solvents, depending on the degree of contamination on the substrate surface.

[0049] The cleaning process includes ultrasonic vibration decontamination, rinsing, and drying. The preferred ultrasonic frequency is 40kHz–80kHz, and the cleaning time is controlled at 2–5 minutes to ensure thorough removal of contaminants without damaging the substrate. Deionized water can be used for rinsing to prevent solvent residue from affecting subsequent processes. After cleaning, the substrate is dried in a hot air circulating oven at 60℃–80℃ for approximately 3–5 minutes to ensure complete evaporation of moisture from the substrate surface and to avoid affecting the subsequent coating effect.

[0050] S2. Perform plasma surface treatment on the substrate;

[0051] Specifically, in a specific embodiment of the present invention, in order to further improve the adhesion of the coating to the surface of the PVC decorative film substrate, the substrate needs to undergo plasma surface treatment. This treatment activates the PVC film surface through the high energy of plasma, increasing its surface energy, thereby improving the wettability and adhesion properties of the coating.

[0052] This step uses a plasma surface treatment machine, employing a mixture of argon (Ar) and oxygen (O2) as the treatment gas to enhance surface activation. The preferred gas ratio is Ar:O2 = 4:1, with plasma power controlled between 50W and 300W and treatment time between 10 and 60 seconds to ensure sufficient surface modification.

[0053] During plasma treatment, argon gas removes organic contaminants and weak chemical bonds from the surface, while oxygen introduces polar groups such as hydroxyl and carbonyl groups, thereby increasing the hydrophilicity and chemical activity of the substrate surface. After plasma modification, the surface energy of the PVC surface can be increased from the original 30-35 mN / m to 50-65 mN / m, effectively improving the spreadability of subsequent coating solutions, allowing the coating to adhere more evenly to the substrate surface and reducing defects.

[0054] After plasma surface treatment is completed, the substrate should proceed to the next process as soon as possible to avoid prolonged exposure that could lead to surface aging or re-coverage by environmental contaminants.

[0055] S3. Prepare the coating solution;

[0056] Specifically, the formulation design of this solution should take into account the adhesion, mechanical properties and functional characteristics of the coating to ensure that it forms a uniform film on the substrate surface and has long-term stability.

[0057] The coating solution mainly consists of film-forming resin, functional additives, solvents, and dispersants, and its preferred mixing ratio range is as follows (by mass percentage):

[0058] Film-forming resin (40-70%): Acrylic resin, polyurethane resin or epoxy resin can be selected. Among them, acrylic resin can give the coating good transparency and weather resistance, while polyurethane resin can enhance wear resistance.

[0059] Antibacterial agent (1-5%): Nano titanium dioxide or nano silver is used as antibacterial functional material. Among them, TiO2 can decompose organic matter through photocatalysis to achieve antibacterial and self-cleaning effects, while nano silver has broad-spectrum antibacterial properties.

[0060] Wear-resistant filler (5-15%): Alumina or silicon carbide micro powder can be selected to improve the hardness and wear resistance of the coating.

[0061] Solvent (10-30%): Volatile solvents such as ethyl acetate, propylene glycol methyl ether acetate or xylene are used to adjust the viscosity of the solution and promote uniform film formation.

[0062] Dispersant (0.5-2%): Use polymeric dispersants, such as BYK-110 and TEGO Dispers 755, to improve the dispersion stability of inorganic fillers in the coating solution and avoid sedimentation or agglomeration.

[0063] The preparation of the coating solution requires the use of a magnetic stirrer to ensure thorough mixing and uniform dispersion of the components. The preparation steps are as follows:

[0064] Basic dissolution: Dissolve the film-forming resin in the solvent on a magnetic stirrer, with the stirring speed controlled at 300-600 rpm and the stirring time at about 30-60 minutes, to ensure that the resin swells fully and forms a homogeneous liquid phase system.

[0065] Functional material dispersion: Add antibacterial agent, wear-resistant filler, and dispersant, and disperse at a speed of 2000–5000 rpm for approximately 30–90 minutes. During this process, the system temperature must be controlled to not exceed 50°C to prevent excessive solvent evaporation or resin degradation.

[0066] Refinement treatment: For fillers that are difficult to disperse evenly, ultrasonic dispersion treatment can be further adopted. The ultrasonic frequency is controlled at 20-40 kHz and the time is 5-15 min to reduce particle agglomeration and improve solution stability.

[0067] Curing: After dispersion, let the coating solution stand for 12-24 hours to allow the bubbles in the system to escape.

[0068] S4. Apply the coating solution evenly to the surface of the substrate;

[0069] Specifically, this step preferably uses spraying, scraping, or dipping methods. Spraying is most suitable for the industrial production of large-area PVC decorative films, as it can achieve uniform coating and improve production efficiency.

[0070] During the spraying process, an automatic spraying machine is used for coating. This equipment is equipped with a fine atomizing spray gun (nozzle diameter 0.2mm~1.0mm). Through air pressure regulation and spray flow control, the coating solution is uniformly atomized and deposited on the substrate surface. The spraying pressure is generally controlled at 0.2~0.6MPa, and the spraying angle is set at 30°~90°. Multiple thin-layer sprayings are used (usually 2~5 layers) to avoid coating sagging or uneven curing caused by a single thick coating. After each spraying, a set resting time (1~3min) is required to allow partial evaporation of the solvent and uniform spread, improving the consistency of the final film.

[0071] For coating thickness control, the final cured dry film thickness is preferably between 5μm and 30μm. For coatings used in general abrasion-resistant and antibacterial applications, the thickness can be controlled between 10μm and 20μm. If higher abrasion resistance and antibacterial effects are required, the coating thickness can be appropriately increased. The uniformity of the coating thickness has a significant impact on the final performance; therefore, a film thickness gauge can be used for testing to ensure that the deviation is controlled within ±2μm.

[0072] During the coating process, to improve the adhesion of the coating to the substrate surface, the substrate can be preheated (40℃~60℃) to reduce the surface tension of the coating solution and promote uniform spreading. Simultaneously, a suitable amount of leveling agent (such as BYK-310, TEGO Flow 370) can be added to reduce surface defects and improve the smoothness and abrasion resistance of the coating. Furthermore, controlling the coating environment is crucial. It is recommended to conduct the coating in a cleanroom environment with a cleanliness level ≥10,000 to reduce airborne particulate contamination and improve the surface quality of the coating. The ambient humidity should be controlled at 40%~60%RH, and the temperature maintained at 20℃~30℃ to avoid solvent evaporation that is too rapid or too slow, which could affect the uniformity of the coating.

[0073] For blade coating, a precision coating machine can be used, with the coating thickness controlled by a blade. This method is suitable for laboratory or small-batch production. The blade gap is set between 10μm and 50μm depending on the target film thickness, and the coating speed is generally 10–50 mm / s. This method can achieve high thickness uniformity, but blade marks may appear on larger substrate areas. Therefore, it is suitable for small-area products with high precision requirements.

[0074] For dip coating, the substrate needs to be evenly immersed in the coating solution for 3–10 seconds, then slowly pulled out at a speed controlled at 50–200 mm / min to ensure uniform coating thickness. Excess solvent is then removed by natural evaporation or gentle hot air drying (40℃–50℃). This method is suitable for substrates with complex shapes or applications requiring high uniformity, but it results in significant solvent loss.

[0075] S5. Microporous structures are formed through solvent exchange phase separation process;

[0076] Specifically, in practice, a suitable film-forming resin (such as polyurethane, polyvinylidene fluoride (PVDF), or polyethersulfone (PES)) and a mixed solvent system (such as dimethylacetamide (DMAc), dimethyl sulfoxide (DMSO), ethyl acetate, etc.) are first selected to prepare the coating solution. After the coating is applied, it is placed in a solvent immersion tank, allowing it to come into contact with the corresponding non-solvent (such as water, ethanol, or an alcohol-water mixture), triggering a solvent exchange process. During this process, the solvent gradually diffuses into the non-solvent phase, while the non-solvent penetrates into the interior of the coating, causing local precipitation of polymer chain segments and the formation of a phase-separated structure, which is ultimately fixed as a microporous structure after drying.

[0077] Key parameters for solvent-exchange phase separation include the type of non-solvent, solvent exchange rate, coating thickness, and environmental control. To ensure the uniformity of the microporous structure, a liquid with a moderate diffusion rate, such as a water-alcohol mixture, is preferred as the non-solvent. Its moderate diffusion coefficient prevents pore structure collapse caused by excessively rapid phase separation. Experiments have shown that a solvent exchange rate of 10–50 μm / s can form a stable microporous layer with pore sizes ranging from 50 nm to 5 μm. However, when the exchange rate is too fast (>100 μm / s), it can easily lead to uncontrolled macroporous structures, affecting the mechanical properties of the coating.

[0078] Furthermore, the influence of ambient humidity on phase separation cannot be ignored. It is recommended to conduct the phase separation under conditions of relative humidity of 40%–60% RH and temperature of 20℃–30℃ to ensure uniform solvent exchange and reduce the influence of external factors on the pore structure. To further optimize the pore structure distribution, surfactants (such as SDS or Pluronic F127) can be added to the non-solvent system to reduce interfacial tension, promote uniform phase separation, and improve the stability of the microporous structure.

[0079] The coating surface after solvent exchange phase separation treatment exhibits a stable microporous structure, and its porosity can be adjusted to 20% to 80% depending on the solvent system and exchange conditions, exhibiting good air permeability and adsorption.

[0080] S6. The coating is UV cured to form a wear-resistant and antibacterial coating.

[0081] Specifically, the coating, after being applied and undergoing solvent exchange phase separation to form a microporous structure, must be immediately subjected to UV curing to prevent solvent residue from affecting the final curing quality. The curing process is carried out using a high-energy UV curing machine. The preferred UV light source is a medium-high pressure mercury lamp (wavelength range: 250-400nm) or a UV-LED lamp (wavelength range: 365-395nm), and its irradiance can be adjusted according to the coating formulation and thickness.

[0082] Recommended UV irradiation parameters are as follows: For coatings using free radical-based photocuring systems (such as acrylic resin systems), the irradiation wavelength should primarily be between 365nm and 385nm, and the energy should be controlled between 800 and 2000 mJ / cm². 2 The curing time is approximately 10-30 seconds. For cationic photocurable systems (such as epoxy resin systems), the irradiation wavelength is mainly 280-320nm, with slightly higher energy requirements, generally controlled at 1500-2500mJ / cm². 2 The curing time is 20-60 seconds.

[0083] The key to the UV curing process lies in the proper matching of photoinitiator and resin to ensure the integrity of curing and the optimization of coating performance. In this invention, the photoinitiator can be an α-hydroxy ketone (such as Irgacure 184), a benzophenone (such as Irgacure 651), or a cationic initiator (such as Irgacure 250), and its addition amount is generally controlled at 1-5 wt% to ensure sufficient curing while avoiding excessive addition that may lead to photosensitive yellowing or increased brittleness. To enhance the wear resistance of the coating, nano-silica or alumina particles (particle size controlled at 50-500 nm, addition amount 5-15%) can be introduced into the formulation. These fillers can form a reinforcing skeleton structure during the curing process, improving the hardness and scratch resistance of the coating, ultimately achieving a coating hardness of 3H-6H, and exhibiting excellent wear resistance in the friction test (ASTM D4060), with a wear rate of less than 0.03 g / 1000 friction cycles.

[0084] For antibacterial function, nano-silver, nano-titanium dioxide or zinc oxide are also introduced into the coating as active antibacterial agents. Among them, nano-silver mainly destroys bacterial cell membranes by releasing Ag+ ions, generating reactive oxygen species, and decomposing bacteria and organic pollutants.

[0085] A surface treatment process equipment for wear-resistant PVC decorative film, comprising:

[0086] Ultrasonic cleaning machines are used to remove oil, dust, and particles from the surface of substrates through ultrasonic vibration.

[0087] A plasma surface treatment machine is used to activate the surface of PVC decorative film using Ar-O2 plasma.

[0088] Magnetic stirrer for uniformly mixing coating solutions;

[0089] A spraying machine is used to uniformly apply a coating solution to the surface of the substrate.

[0090] Solvent immersion tank is used to complete the solvent exchange phase separation process;

[0091] A UV curing machine is used to cure coatings with UV light, forming a wear-resistant and antibacterial coating.

[0092] Hot air circulating oven is used to heat coatings evenly by circulating hot air.

[0093] Specifically, firstly, the substrate surface is cleaned using an ultrasonic cleaner. The cleaner uses ultrasonic vibrations to remove oil, dust, and particles from the substrate surface. After this step, the substrate surface will be clean and ready for subsequent processing.

[0094] After cleaning, the substrate enters a plasma surface treatment machine for surface activation. Ar-O2 plasma is used to activate the PVC film surface, increasing its hydrophilicity and adhesion, preparing it for coating adhesion.

[0095] Next, prepare the coating solution and mix it evenly using a magnetic stirrer to ensure its stability and uniformity. The stirrer prevents sedimentation in the coating solution, ensuring coating quality.

[0096] Once the coating solution is mixed, the substrate is transferred to the sprayer, where the coating solution is sprayed evenly onto the substrate surface. The sprayer can adjust the spraying speed and coating thickness as needed to ensure coating consistency.

[0097] After the coating is applied, the substrate needs to be immersed in a solvent immersion tank for solvent exchange phase separation to ensure that the solvent in the coating is fully removed and a more stable coating is formed.

[0098] After solvent exchange, the substrate enters a UV curing machine for UV curing. This process uses ultraviolet light to rapidly cure the coating, enhancing its wear resistance and antibacterial properties.

[0099] Finally, the UV-cured substrate enters a hot air circulating oven for final heat treatment to ensure the coating is completely dry. The uniform circulation of hot air ensures the coating surface is thoroughly dried, preventing peeling during subsequent use.

[0100] Based on the above steps, the following embodiments will be provided:

[0101] Example 1: Preparation of antibacterial coating:

[0102] Step 1: Use deionized water and ethanol to ultrasonically clean the PVC decorative film. Set the cleaning time to 15 minutes to ensure the surface is free of oil and impurities.

[0103] Step 2: Place the cleaned PVC film into the plasma treatment machine. Use an Ar-O2 gas mixture, set the treatment power to 65W, and the treatment time to 45 seconds. After treatment, the surface energy of the substrate is significantly improved, providing better adhesion for the coating.

[0104] Step 3: Mix the coating solution according to the following ratio:

[0105] Polyurethane: 35%,

[0106] Epoxy resin and its curing agent: 40%,

[0107] Antibacterial functional group (benzothiazole derivative): 18%,

[0108] Hydrogen bond enhancer (polyvinyl alcohol): 5%,

[0109] Photocatalyst (zinc oxide, 50nm particle size): 4%,

[0110] Solvent (mixed solvents dimethylformamide and ethanol, 1:1): 8%.

[0111] Use a magnetic stirrer to stir for 30 minutes at room temperature to ensure the solution is homogeneous.

[0112] Step 4: Use a spray gun to evenly apply the solution to the substrate surface. Set the nozzle diameter to 1mm, the air pressure to 0.3MPa, and the spraying speed to 100mm / s.

[0113] During spraying, ensure the coating thickness is uniform and avoid areas where the coating is too thick or too thin.

[0114] Step 5: Immerse the coated membrane in ethanol solvent. This allows N-methylpyrrolidone to exchange between the inside and outside of the membrane, forming a microporous structure. After solvent exchange is complete, maintain the membrane immersion time for 2 hours to ensure the uniformity of the micropores.

[0115] Step 6: Place the coating film in a UV curing machine, set the light source wavelength to 365nm, and the curing time to 3 minutes. After curing, the coating hardness is enhanced, and the antibacterial function is strengthened.

[0116] Example 2: Preparation of high wear-resistant coating:

[0117] Step 1: Clean the PVC film in an ultrasonic cleaner with deionized water and ethanol for 20 minutes to ensure that contaminants on the substrate are removed.

[0118] Step 2: Place the substrate in a plasma treatment machine, using an Ar-O2 gas mixture, with a treatment power of 70W and a time of 50 seconds. The treated film surface exhibits high surface energy, which is beneficial for coating adhesion.

[0119] Step 3: Prepare the coating solution according to the following proportions:

[0120] Polyurethane: 32%,

[0121] Epoxy resin and its curing agent: 42%,

[0122] Antibacterial functional group (benzothiazole derivative): 20%,

[0123] Ionic bond stabilized antibacterial agent (silver ion and quaternary ammonium salt complex): 6%,

[0124] Photocatalyst (zinc oxide): 4%,

[0125] Solvent: Mixed solvent of dimethylformamide and ethanol (2:1): 8%.

[0126] After mixing the ingredients, stir in a magnetic stirrer for 45 minutes to ensure the coating solution is uniform.

[0127] Step 4: Apply the coating to the substrate using a spray gun. Spraying parameters: nozzle diameter 1.2mm, air pressure 0.25MPa, spraying speed 120mm / s. After each coat, ensure the coating is uniform and free of bubbles, and control the coating thickness between 10-15μm.

[0128] Step 5: The coated membrane is immersed in ethanol solvent for 2 hours, allowing N-methylpyrrolidone to diffuse outwards and ethanol to enter the membrane, forming a microporous structure. After immersion, the membrane surface structure is optimized, and the wear resistance and air permeability of the coating are significantly improved.

[0129] Step 6: Place the coated film into a UV curing machine, set the curing wavelength to 365nm, and the curing time to 5 minutes. The cured film coating is harder, and its wear resistance and antibacterial properties are enhanced.

[0130] Example 3: Preparation of a high-stability coating:

[0131] Step 1: Clean the PVC film using an ultrasonic cleaner. The cleaning liquid is a mixture of deionized water and ethanol, and the cleaning time is set to 15 minutes.

[0132] Step 2: Perform plasma surface treatment on the PVC film using an Ar-O2 gas mixture, with a power setting of 60W and a treatment time of 40 seconds.

[0133] Enhance surface activity to ensure effective coating adhesion.

[0134] Step 3: Prepare the coating solution by mixing according to the following proportions:

[0135] Polyurethane: 38%,

[0136] Epoxy resin and its curing agent: 40%,

[0137] Antibacterial functional group (benzothiazole derivative): 15%,

[0138] Hydrogen bond enhancer (polyvinyl alcohol): 7%,

[0139] Photocatalyst (zinc oxide): 5%,

[0140] Solvent: Mixed solvent of dimethylformamide and ethanol (3:1): 10%.

[0141] Stir in a magnetic stirrer for 40 minutes to ensure the solution is homogeneous and free of bubbles.

[0142] Step 4: Apply the solution to the PVC film surface using a spray gun. Set the nozzle diameter to 1mm, the air pressure to 0.3MPa, and the spraying speed to 80mm / s. Ensure the coating is uniform, and control the coating thickness to 12-18μm.

[0143] Step 5: After coating, immerse the membrane in ethanol solvent and wait 1.5 hours to complete solvent exchange and phase separation to form a uniform microporous structure.

[0144] Step 6: Place the film in a UV curing machine, set the curing wavelength to 400nm, and the curing time to 4 minutes. The UV-cured coating is more stable, enhancing its weather resistance, antibacterial properties, and abrasion resistance.

[0145] Comparative Example 1: Preparation of antibacterial coating (without photocatalyst)

[0146] process:

[0147] Step 1: Use deionized water and ethanol to ultrasonically clean the PVC decorative film for 15 minutes to ensure that the surface is free of oil and impurities.

[0148] Step 2: Place the cleaned PVC film into the plasma treatment machine, using an Ar-O2 gas mixture, with a treatment power of 65W and a treatment time of 45 seconds.

[0149] Step 3: Mix the coating solution according to the following ratio:

[0150] Polyurethane: 35%,

[0151] Epoxy resin and its curing agent: 40%,

[0152] Antibacterial functional group (benzothiazole derivative): 18%,

[0153] Hydrogen bond enhancer (polyvinyl alcohol): 5%,

[0154] Ionic bond stabilized antibacterial agent (silver ion and quaternary ammonium salt complex): 6%,

[0155] Solvent (mixed solvents dimethylformamide and ethanol, 1:1): 8%.

[0156] Use a magnetic stirrer to stir for 30 minutes at room temperature to ensure the solution is homogeneous.

[0157] Step 4: Use a spray gun to evenly apply the solution to the substrate surface. Set the nozzle diameter to 1mm, the air pressure to 0.3MPa, and the spraying speed to 100mm / s.

[0158] During spraying, ensure the coating thickness is uniform and avoid areas that are too thick or too thin.

[0159] Step 5: Immerse the coated membrane in ethanol solvent. This allows N-methylpyrrolidone to exchange between the inside and outside of the membrane, forming a microporous structure. After solvent exchange is complete, maintain the membrane immersion time for 2 hours to ensure the uniformity of the micropores.

[0160] Step 6: Place the coating film in a UV curing machine, set the light source wavelength to 365nm, and the curing time to 3 minutes. After curing, the coating hardness is enhanced, and the antibacterial function is strengthened.

[0161] Comparative Example 2: Preparation of high wear-resistant coating (without hydrogen bond enhancer)

[0162] process:

[0163] Step 1: Clean the PVC film in an ultrasonic cleaner with deionized water and ethanol for 20 minutes to ensure that contaminants on the substrate are removed.

[0164] Step 2: Place the substrate in a plasma treatment machine, using an Ar-O2 gas mixture, with a treatment power of 70W and a time of 50 seconds. The treated film surface exhibits high surface energy, which is beneficial for coating adhesion.

[0165] Step 3: Prepare the coating solution according to the following proportions:

[0166] Polyurethane: 32%,

[0167] Epoxy resin and its curing agent: 42%,

[0168] Antibacterial functional group (benzothiazole derivative): 20%,

[0169] Ionic bond stabilized antibacterial agent (silver ion and quaternary ammonium salt complex): 6%,

[0170] Photocatalyst (zinc oxide): 4%,

[0171] Solvent: Mixed solvent of dimethylformamide and ethanol (2:1): 8%.

[0172] Step 4: Apply coating to the substrate using a spray gun. Spraying parameters: nozzle diameter 1.2mm, air pressure 0.25MPa, spraying speed 120mm / s.

[0173] After each coating, ensure the coating is uniform and free of bubbles, and control the coating thickness between 10-15μm.

[0174] Step 5: After coating, immerse the membrane in ethanol solvent and wait 1.5 hours to complete solvent exchange and phase separation to form a microporous structure.

[0175] Step 6: Place the coated film into a UV curing machine, set the curing wavelength to 365nm, and the curing time to 5 minutes. The cured coating is harder, and its wear resistance and antibacterial properties are enhanced.

[0176] Comparative Example 3: Preparation of High-Stability Coatings (without heat treatment)

[0177] process:

[0178] Step 1: Clean the PVC film using an ultrasonic cleaner. The cleaning liquid is a mixture of deionized water and ethanol, and the cleaning time is set to 15 minutes.

[0179] Step 2: Perform plasma surface treatment on the PVC film using an Ar-O2 gas mixture, with a power setting of 60W and a treatment time of 40 seconds. This enhances surface activity and ensures effective coating adhesion.

[0180] Step 3: Prepare the coating solution by mixing according to the following proportions:

[0181] Polyurethane: 38%,

[0182] Epoxy resin and its curing agent: 40%,

[0183] Antibacterial functional group (benzothiazole derivative): 15%,

[0184] Hydrogen bond enhancer (polyvinyl alcohol): 7%,

[0185] Photocatalyst (zinc oxide): 5%,

[0186] Solvent: Mixed solvent of dimethylformamide and ethanol (3:1): 10%.

[0187] Stir in a magnetic stirrer for 40 minutes to ensure the solution is homogeneous and free of bubbles.

[0188] Step 4: Apply the solution to the PVC film surface using a spray gun. Set the nozzle diameter to 1mm, the air pressure to 0.3MPa, and the spraying speed to 80mm / s. Ensure the coating is uniform, and control the coating thickness to 12-18μm.

[0189] Step 5: After coating, immerse the membrane in ethanol solvent and wait 1.5 hours to complete solvent exchange and phase separation to form a uniform microporous structure.

[0190] Step 6: Place the film in a UV curing machine, set the curing wavelength to 400nm, and the curing time to 4 minutes.

[0191] Experiment 1: Antibacterial performance test:

[0192] This experiment aimed to compare the differences in antibacterial performance between the examples and comparative examples in practical applications (such as wall panels and cabinet surfaces). Three samples were selected: Example 1, Comparative Example 1, and Comparative Example 2. All samples used PVC decorative film surface coatings, which underwent appropriate surface treatment and coating application. Common bacteria (such as Staphylococcus aureus and Escherichia coli) were cultured during the testing process to examine the antibacterial ability of the coating surface.

[0193] Materials preparation: Three different coated samples (Example 1, Comparative Example 1, Comparative Example 2) and an uncoated substrate (as a control group) were taken.

[0194] Bacterial culture: Staphylococcus aureus and Escherichia coli were used for bacterial culture. The culture medium was nutrient agar, and the bacterial strains were incubated for 24 hours using the inoculation method to generate a certain number of bacterial colonies.

[0195] Coating treatment: The coating of each PVC film substrate sample was treated according to the corresponding process (e.g., Example 1 used a photocatalyst, Comparative Example 1 and Comparative Example 2 did not use a photocatalyst and did not use a hydrogen bonding enhancer, respectively). Each sample was cured under a UV light source after coating.

[0196] Antimicrobial test: The treated sample surface was placed on a culture medium and inoculated with bacteria. The incubation temperature was 37°C for 24 hours, and the bacterial growth on the sample surface was recorded. The antimicrobial effect was assessed using colony counting (CFU, colony forming units). Each test was performed at least three times independently to ensure data reliability.

[0197] Data collection: Measure bacterial growth and count the number of colonies on the coating of each sample.

[0198] Antibacterial performance test data:

[0199]

[0200] The results of Experiment 1 significantly demonstrate the impact of different coatings on antibacterial properties. Example 1, with a coating containing a photocatalyst (zinc oxide), showed significantly lower colony counts of Staphylococcus aureus and Escherichia coli compared to Comparative Examples 1 and 2. Particularly in the Escherichia coli test, Example 1 exhibited superior antibacterial performance. This is likely due to the photocatalytic reaction initiated by the zinc oxide photocatalyst under ultraviolet light, leading to the generation of reactive oxygen species (such as ·OH) on the coating surface upon contact with bacteria, which then decomposes the bacterial cell wall and inhibits their reproduction. The experimental data also showed that the antibacterial effects of Comparative Examples 1 and 2, without the addition of a photocatalyst, were significantly reduced, especially Comparative Example 1, which lacked photocatalytic function and exhibited relatively poor antibacterial performance.

[0201] Mechanistically, plasma treatment helps increase the hydrophilicity and number of active groups on the membrane surface, while the use of a hydrogen bond enhancer (polyvinyl alcohol) further strengthens the binding force between the coating and bacteria, thereby enhancing the coating's antibacterial ability. In Comparative Example 2, the lack of a hydrogen bond enhancer resulted in poor coating stability and antibacterial function. Although the coating did not show significant damage, its surface microenvironment was not further optimized, affecting the antibacterial effect.

[0202] Furthermore, the experimental data show that the synergistic effect of UV curing and photocatalysts plays a crucial role in preventing bacterial growth. In prolonged exposure to bacterial environments, the coating of Example 1 exhibited a longer-lasting antibacterial effect, indicating that the combination of photocatalysts and surface treatment techniques can significantly improve the antibacterial performance of coatings in practical applications.

[0203] Experiment 2: Abrasion Resistance Test

[0204] Experiment 2 aimed to evaluate the abrasion resistance of different coatings in practical applications, particularly the durability of coatings on wall panels and cabinet surfaces. The tested samples included Example 1, Comparative Example 1, and Comparative Example 2. Friction and wear tests were conducted to simulate wear conditions during long-term use, observing surface changes in the coatings, including hardness, scratches, and peeling. The friction and wear process was performed on a standard abrasion machine, and the abrasion resistance of the coatings was recorded to ensure that each coating could withstand different frictional conditions.

[0205] Sample preparation: Prepare three different coating samples (Example 1, Comparative Example 1, and Comparative Example 2), ensuring that the coating thickness of each sample is consistent (approximately 12 μm). After all samples are coated, cure them using a UV curing device to ensure that the coating is completely dry.

[0206] Friction and wear test: A Taber abrasion tester was used, set to a load of 500g and a friction rate of 50 revolutions per minute for 10 hours. A steel ball (6mm in diameter) was used to simulate wear against the surface of the coated sample. Wear was recorded and photographed every hour.

[0207] Measuring Coating Changes: Measure the surface hardness of the coating (using a Mohs hardness tester) and inspect the coating surface, recording any scratches, peeling, or discoloration after wear. After the experiment, use a gloss meter to measure the gloss change of the coating.

[0208] Data collection and analysis: After friction and wear testing, the surface damage of each sample was recorded, with a focus on measuring the coating's wear resistance, hardness changes, and surface cracks. The wear data of different samples were compared to analyze their wear resistance performance.

[0209] Abrasion resistance test data table:

[0210]

[0211]

[0212] The results of Experiment 2 show that Example 1 exhibited excellent wear resistance, with the smallest decrease in hardness (only 0.5 Mohs units) and minimal change in gloss, indicating that the coating maintained good appearance and protective effect even after prolonged friction and wear. Based on the experimental mechanism, the zinc oxide photocatalyst may have provided stronger stability within the coating and effectively reduced microcracks caused by friction on the surface. The plasma treatment in the experiment helped improve the hydrophilicity of the coating surface, resulting in a more uniform coating distribution and reducing particle accumulation during wear, further enhancing wear resistance.

[0213] Comparative Examples 1 and 2 exhibited poor wear resistance, especially Comparative Example 2, which showed obvious scratches and slight peeling. Experimental data indicates that Comparative Example 2, lacking a hydrogen bond reinforcing agent, had lower coating stability than Example 1, and surface cracks were more prone to forming. Coatings lacking this reinforcing function cannot effectively resist external pressure and friction during long-term wear, leading to increased brittleness. This also demonstrates the positive effect of hydrogen bond reinforcing agents on coating wear resistance.

[0214] These test data suggest that the coating of Example 1 exhibits superior long-term abrasion resistance in everyday applications. In practical applications on cabinet surfaces or wall panels, coatings containing photocatalysts and hydrogen bond enhancers can significantly reduce damage caused by daily friction, thereby extending their service life and maintaining good appearance and functionality.

[0215] Experiment 3: Anti-fouling and self-cleaning performance test:

[0216] The objective of Experiment 3 was to test the stain resistance of different coatings on wall panel and cabinet surfaces and to evaluate their self-cleaning function. Test samples included Example 1, Comparative Example 1, and Comparative Example 2. During the experiment, each sample was exposed to common stain sources (such as oil, ink, food residue, etc.), and the ability of these stains to be removed from the coating surface was observed over a specific time period. The experiment simulated pollution conditions in a daily environment to test whether the coating could effectively remove stains and keep the surface clean.

[0217] Sample preparation: Prepare coating samples, Example 1, Comparative Example 1 and Comparative Example 2. All samples have a coating thickness of about 12 μm and are UV cured after coating.

[0218] Contaminant Addition: Each coated sample was exposed to different stain sources, including oil (cooking oil), ink, juice, etc. Each contaminant was applied separately to the surface of each sample and allowed to air dry, forming a typical stain layer.

[0219] Self-cleaning test: The sample surface was wiped with a cleaning agent (stain remover). Before and after the test, the stain removal status was recorded through photography and visual inspection. After each cleaning, the surface gloss was measured using a gloss meter to observe the stain removal effect. The experiment lasted for 2 hours, and the cleanliness of the samples was checked periodically.

[0220] Data recording and analysis: Cleaning effectiveness was recorded every 30 minutes. A rating scale of 1 to 5 was used to assess stain removal effectiveness, with 1 representing complete removal and 5 representing no removal. Surface changes after stain removal were recorded using a gloss meter and visual evaluation.

[0221] Self-cleaning performance test data:

[0222]

[0223] The results of Experiment 3 show that the coating of Example 1 exhibits a significant self-cleaning effect, especially when dealing with oil stains, ink stains, and juice stains, with good gloss restoration and obvious stain removal. The photocatalyst (zinc oxide) plays a key role in the coating, particularly after exposure to the stain source. The coating surface activates a photocatalytic reaction, decomposing the organic matter in the stains, thereby improving the cleaning effect. Mechanistic analysis indicates that the photocatalytic effect gives the coating surface more hydrophobic properties, reducing the time and intensity of contaminant adhesion. Therefore, even stubborn oil stains and ink stains can be removed quickly with simple wiping.

[0224] Comparative Examples 1 and 2 performed poorly, especially the coating of Comparative Example 2, which failed to effectively remove oil and juice stains, demonstrating the direct impact of the lack of photocatalyst on self-cleaning performance. Comparative Example 1, lacking zinc oxide, although showing improved surface energy, still did not match the self-cleaning function of Example 1. The surface showed obvious oil and ink marks, and the wiping effect during cleaning was not as ideal as in Example 1, indicating that the coating lacking photocatalytic ability is significantly limited in stain removal.

[0225] The results of this experiment not only verified the effect of zinc oxide in enhancing the self-cleaning performance of the coating, but also further proved that the combination of plasma surface treatment and photocatalyst can significantly improve the stain removal efficiency of the coating surface. Especially in complex environments, such as kitchen and home applications, this coating can effectively reduce stain adhesion and improve the ease of use and durability of the coating.

[0226] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A surface treatment process for wear-resistant PVC decorative film, characterized in that, Includes the following steps: S1. Provide a PVC decorative film substrate and clean the substrate; S2. Perform plasma surface treatment on the substrate; S3. Prepare the coating solution; S4. Apply the coating solution evenly to the surface of the substrate; S5. Microporous structures are formed through solvent exchange phase separation process; S6. UV curing treatment is applied to the coating to form a wear-resistant and antibacterial coating.

2. The surface treatment process for wear-resistant PVC decorative film according to claim 1, characterized in that, The coating solution in step S3 comprises the following components by weight percentage: Polyurethane: 30%-40%; Epoxy resin and its curing agent: 35%-45%; Antibacterial functional groups: 15%-22%; Hydrogen bond enhancer: 5%-10%; Ionic bond stabilizer antibacterial agent: 3%-8%; Photocatalyst: 3%-7%; Solvent: 10%-15%.

3. The surface treatment process for wear-resistant PVC decorative film according to claim 1, characterized in that, In step S2, the plasma surface treatment uses Ar-O2 plasma with a treatment power of 50-80W and a treatment time of 30-60 seconds.

4. The surface treatment process for wear-resistant PVC decorative film according to claim 2, characterized in that, The antibacterial functional group is a benzothiazole derivative, the hydrogen bond enhancer is polyvinyl alcohol, the ionic bond stabilizing antibacterial agent includes a silver ion and quaternary ammonium salt complex, with a mixing ratio of 1:10 to 1:100, the photocatalyst is zinc oxide with a particle size of 50 nm, and the solvent is a mixed solvent of dimethylformamide and ethanol, with a mixing ratio of 1:1 to 3:

1.

5. The surface treatment process for wear-resistant PVC decorative film according to claim 1, characterized in that, Step S1 includes cleaning the substrate using deionized water, ethanol, and ultrasonic cleaning.

6. The surface treatment process for wear-resistant PVC decorative film according to claim 1, characterized in that, The S4 step uses a spraying method, and the spraying parameters include a nozzle diameter of 0.2-1.5 mm, an air pressure of 0.1-0.4 MPa, and a spraying moving speed of 50-200 mm / s.

7. The surface treatment process for wear-resistant PVC decorative film according to claim 1, characterized in that, The solvent exchange phase separation process includes: S51. Immerse the coated film in ethanol; S52 and N-methylpyrrolidone diffuse outwards, while ethanol enters the membrane, initiating phase separation. S53. The polymer phase is enriched to form a continuous phase, while the solvent phase precipitates and forms micropores.

8. The surface treatment process for wear-resistant PVC decorative film according to claim 1, characterized in that, In step S6, the wavelength of the UV curing light source is 365nm to 405nm.

9. The surface treatment process for wear-resistant PVC decorative film according to claim 1, characterized in that, Step S6 is followed by heat treatment, in which the UV-cured coating is subjected to heat treatment within a temperature range of 50-120°C.

10. A surface treatment process equipment for wear-resistant PVC decorative film, used in the surface treatment process for wear-resistant PVC decorative film as described in any one of claims 1-9, characterized in that, include: Ultrasonic cleaning machines are used to remove oil, dust, and particles from the surface of substrates through ultrasonic vibration. A plasma surface treatment machine is used to activate the surface of PVC decorative film using Ar-O2 plasma. Magnetic stirrer for uniformly mixing coating solutions; A spraying machine is used to uniformly apply a coating solution to the surface of the substrate. Solvent immersion tank is used to complete the solvent exchange phase separation process; A UV curing machine is used to cure coatings with UV light, forming a wear-resistant and antibacterial coating. Hot air circulating oven is used to heat coatings evenly by circulating hot air.

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