Odor-free scratch-resistant elastic bending UV (ultraviolet) excimer skin-touch varnish

Abstract

The invention discloses an odorless scratch-resistant elastic bending UV (ultraviolet) excimer skin-touch varnish, which relates to the technical field of coatings and comprises the following components in percentage by mass: 10-30% of functional acrylate resin, 10-30% of a solvent, 10-30% of a solvent, 10-30% of a solvent and 10-30% of a solvent. 40 to 80% of modified polyurethane acrylate resin; 0.1-1% of a leveling agent; 0.1-1% of a defoaming agent; 0.1-4% of an organosilicon auxiliary agent; 0.5 to 2% of 2, 4, 6-trimethylbenzoyl diphenyl phosphine oxide; 0.5 to 7% of 2-hydroxy-4 '-(2-hydroxyethoxy)-2-methyl propiophenone, and the balance of water; 0.3-1% of a wetting dispersant; 2-5% of UV anti-settling slurry; 1-5% of wax powder; and 5-30% of nano sol. According to the UV quasi-molecular skin-touch varnish disclosed by the invention, through the combined action of an odorless resin system, fluorosilicone modified and enhanced three-functional-group elastic resin, nano-zirconia phase change toughening and a crosslinkable fixing auxiliary agent, multiple pairs of performance contradictions of elasticity and hardness, instant effect and durability, odorless effect and stability and the like in a traditional elastic bending UV coating are successfully solved; and the high-performance skin-touch coating with excellent elastic bending property, lasting high scratch resistance, real odor removal effect and good stability is obtained.

Description

Technical Field

[0001] This invention relates to the field of coatings technology, specifically to a low-odor, scratch-resistant, flexible, and skin-feeling UV excimer clear topcoat. Background Technology

[0002] Ordinary UV paints have a high gloss and a stiff feel, making it difficult to achieve a smooth, skin-like touch. While UV excimer skin-feel paints can provide a matte finish, their inflexible film limits their application on shaped workpieces. In contrast, flexible UV excimer skin-feel paints combine an extremely matte finish with a comfortable feel, and their film can be bent into various shapes. They are widely used in furniture, flexible electronics, and automotive interiors, and can help furniture manufacturers simplify edge banding processes, achieving cost reduction and efficiency improvement. In recent years, market demand for this type of paint has grown rapidly, while higher performance requirements have also been placed on it.

[0003] However, the flexible bending UV excimer skin-feel varnishes currently on the market still have the following two major problems: 1. The paint film has poor scratch resistance and insufficient durability. To maintain the elasticity of the paint film, existing products generally use a large amount of low-functional group resins (such as difunctional polyurethane acrylates), resulting in low paint film hardness and weak scratch resistance. Although adding high-functional group resins can improve hardness, excessive use will make the paint film brittle and affect bending performance. Some products improve initial scratch resistance by adding organosilicon additives (1%–3%), but because they do not crosslink with the system, they easily migrate to the paint film surface and gradually accumulate. Usually, the scratch resistance effect decreases after 20–30 days, and cannot achieve long-lasting protection.

[0004] 2. The paint film has a noticeable odor; it's difficult to achieve both odor neutralization and stability. The odor of paint film mainly comes from photoinitiators and residual monomers. Current technologies often use macromolecular photoinitiators or initiators with special structures to reduce odor, but there are still obvious limitations: (1) Macromolecular initiators need to be combined with active amines, which affects the yellowing resistance of the paint film, and amines themselves have an odor; (2) Although special structure odor-neutralizing initiators (such as JRCure-2959) have low odor, they have poor compatibility in the system, especially at low temperature. They are prone to precipitation and even if reheated, it is difficult to restore uniform dissolution, which affects the stability of coating storage and construction. Summary of the Invention

[0005] The purpose of this invention is to provide an odor-free, scratch-resistant, flexible, and skin-feeling UV excimer clear topcoat that can solve the above-mentioned problems. This invention's UV excimer clear topcoat, through the combined action of an odor-free resin system, a fluorosilicone-modified and enhanced trifunctional elastic resin, nano-zirconia phase transformation toughening, and a crosslinking fixative, successfully resolves multiple performance contradictions in traditional flexible and flexible UV coatings, such as "elasticity and hardness," "immediate effect and durability," and "odor-free and stability." Ultimately, it obtains a high-performance skin-feeling coating that simultaneously possesses excellent flexible bending properties, durable high scratch resistance, a truly odor-free effect, and good stability.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: A low-odor, scratch-resistant, flexible, bendable UV excimer skin-feel clear topcoat, comprising the following components by weight percentage: Functional acrylic resins: 10-30%; Modified polyurethane acrylate resin: 40-80%; Leveling agent: 0.1-1%; Defoamer: 0.1-1%; Organosilicon additives: 0.1-4%; 2,4,6-Trimethylbenzoyldiphenylphosphine oxide: 0.5-2%; 2-Hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone: 0.5-7%; Wetting and dispersing agent: 0.3-1%; UV antisettling slurry: 2-5%; Wax powder: 1-5%; Nanosol: 5-30%; Preferably, the functional acrylic resin used is M151 resin from Kaiping Zicai Chemical Co., Ltd.

[0007] Preferably, the modified polyurethane acrylate resin is a fluorosilicone modified trifunctional polyurethane acrylate resin.

[0008] Preferably, the leveling agent is TEGO® Glide 450; the defoamer is TEGO® Airex 920.

[0009] Preferably, the organosilicon additive is a UV-reactive organosilicon additive.

[0010] Preferably, the 2,4,6-trimethylbenzoyl diphenylphosphine oxide is JRCure-1108 from Jiuri New Materials Co., Ltd.; and the 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone is JRCure-2959 from Jiuri New Materials Co., Ltd.

[0011] Preferably, the wetting and dispersing agent is BYK Chemical's BYK-LP W 20084; the UV anti-settling slurry is a hydrophobic fumed silica slurry.

[0012] Preferably, the wax powder is water-based polyethylene wax micro powder.

[0013] Preferably, the nanosol is a UV solvent-free nanozirconia sol.

[0014] Preferably, the mixture further comprises, by weight percentage, 0.1-0.5% polyamide wax.

[0015] This invention provides a low-odor, scratch-resistant, flexible, and bendable UV excimer surface-feel coating with the following beneficial effects: This invention relates to a low-odor, scratch-resistant, flexible, and bendable UV excimer surface-feel clear topcoat. It utilizes a fluorosilicone-modified trifunctional polyurethane acrylate resin as the main resin. The polyurethane backbone provides excellent flexibility and resilience, ensuring the coating film can be repeatedly bent without cracking. The trifunctional structure also provides a moderate crosslinking density, imparting basic hardness to the coating film and overcoming the insufficient hardness of traditional difunctional elastic resins. Furthermore, the functional acrylate resin itself has a high elongation, further enhancing and improving the flexibility and impact resistance of the coating film. This invention relates to a UV-reactive, scratch-resistant, flexible, and skin-feeling clear topcoat made of UV-reactive silicone additives that are chemically bonded to the paint film network, avoiding the migration loss of conventional silicones and giving the paint film excellent and long-lasting scratch resistance, stain resistance, and slip-resistant properties. This invention relates to a low-odor, scratch-resistant, flexible, UV-excimer clear topcoat with a skin-feel. Fluorosilicone modified segments can oriented and align on the surface of the coating film, permanently reducing surface tension and coefficient of friction, providing a smooth feel and initial scratch resistance. The nanoscale dispersion and unique phase transformation toughening effect of nano-zirconia sol can significantly improve the microhardness, abrasion resistance, and scratch resistance of the coating film without increasing its brittleness. Wax powder floats to the surface of the coating film to form a physical protective layer, which, in synergy with the above components, further enhances the surface's scratch resistance and abrasion resistance. This invention relates to a low-odor, scratch-resistant, flexible, and skin-feeling UV excimer clear topcoat. It utilizes 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone as the main initiator, which possesses low odor and low yellowing properties, thus reducing odor sources at the source. Innovatively, it completely replaces the reactive diluent monomer with a high-hydroxyl content functional acrylic resin, thoroughly eliminating the odor problem caused by monomer residue and achieving a low-odor finish. Furthermore, by leveraging the high polarity and hydroxyl properties of M151 resin, the solubility of JRCure-2959 in the system is greatly improved, effectively preventing its precipitation during low-temperature storage and ensuring the product's storage stability and usability under extreme cold conditions. This invention relates to a low-odor, scratch-resistant, flexible, and bendable UV excimer clear topcoat with a skin-feel. The photoinitiator uses a combination of JRCure-2959 and TPO, which can achieve efficient curing without the need for easily yellowing reactive amines, thereby improving the long-term yellowing resistance of the paint film. The TPO photoinitiator has a main absorption peak at 380nm, which can enhance the absorption of long-wave ultraviolet light, improve the deep curing efficiency and curing completeness, and help to further reduce odor and improve performance. This invention relates to a low-odor, scratch-resistant, flexible, and skin-feeling UV excimer clear topcoat. Through the rational combination of wetting and dispersing agents, leveling agents, and defoamers, it ensures good application performance of the coating and obtains a smooth and even paint film. The synergistic use of UV anti-settling agent and polyamide wax constructs a stable anti-settling network, effectively preventing the sedimentation of heavy components such as nano-sols and wax powders, and ensuring the product's storage stability and performance consistency. Detailed Implementation

[0016] To enable those skilled in the art to better understand the technical solution of the present invention, the product of the present invention will be further described in detail below with reference to embodiments.

[0017] It should be noted that all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0018] A clean, scratch-resistant, flexible, and flexible UV excimer surface-feel coating, by weight percentage, comprises the following components: 10-30% functional acrylic resin; 40-80% modified polyurethane acrylic resin; 0.1-1% leveling agent; 0.1-1% defoamer; 0.1-4% silicone additive; 0.5-2% 2,4,6-trimethylbenzoyl diphenylphosphine oxide; 0.5-7% 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone; 0.3-1% wetting and dispersing agent; 2-5% UV antisettling agent; 1-5% wax powder; and 5-30% nano-sol. In this invention, the functional acrylate resin can, on the one hand, match and fully dissolve 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone, allowing the addition amount of this odor-neutralizing initiator in the formulation to be as high as 7% or more, breaking through conventional limitations. Furthermore, it does not precipitate even in low-temperature environments below -10°C, solving the industry pain point of low-temperature storage stability. On the other hand, it completely replaces the essential reactive diluent monomer in traditional UV coatings, fundamentally eliminating the small molecule odor source remaining due to incomplete monomer conversion, thus achieving the odor-neutralizing function of the paint film. The modified polyurethane acrylate resin uses fluorosilicone-modified trifunctional groups, which, on the one hand, provide the necessary hardness and resistance without significantly sacrificing flexibility like higher-functionality resins, cleverly balancing the traditional contradiction between "bending ability" and "basic hardness." On the other hand, the fluorosilicone segments are chemically anchored on the polymer network, forming a stable low surface energy layer on the surface. This differs from physically added additives, avoiding performance degradation due to migration and wear, and making scratch resistance and stain resistance permanent. The nano-sol, through a phase change toughening mechanism, significantly improves the hardness, wear resistance, and scratch resistance of the paint film while almost completely preserving its flexibility and bending performance. This solves the problem of "high scratch resistance inevitably leading to brittleness." Furthermore, the nanoscale dispersion provides a large specific surface area, resulting in a stronger bond with the resin and a more significant reinforcing effect. The silicone additive used is Silok® 8586 from Silok. This additive has active groups at the end of its molecules that can participate in UV curing, such as acrylate groups, which can copolymerize with the resin in the system, thereby chemically bonding it to the paint film network. Compared with conventional physically migrating silicone additives, it is firmly fixed in the network structure and will not migrate or volatilize over time, thus providing a durable and stable low coefficient of friction surface, with long-lasting scratch resistance and a smooth feel. The wax powder, as a solid lubricant and hard particles, floats to the outermost layer of the paint film during the curing process, forming a micro-uneven physical protective layer. It works synergistically with the fluorosilicone surface layer and nano-zirconia reinforcement to form a "physical-chemical composite barrier", further reducing the coefficient of friction and dispersing external scratching stress through its own small deformation and rolling effect.The photoinitiator system uses JRCure-2959 as the main initiator. Its molecular structure determines its pyrolysis-type initiation mechanism, which has no by-product odor and good resistance to yellowing. TPO is used as an auxiliary initiator, with absorption wavelength matching LED pre-curing to ensure simultaneous initiation of deep and surface layers. This combination eliminates the need for active amine co-initiators that can cause yellowing and odor, ensuring odor neutrality and resistance to yellowing from the source. Combined with the dissolving effect of M151 resin, it completely solves the storage stability bottleneck of high-efficiency odor neutralizing initiators in practical applications. The wetting and dispersing agent, anti-settling agent, and polyamide wax form a rheological and storage stable system. The wetting and dispersing agent reduces the surface energy of nanoparticles and wax powder, preventing agglomeration. The anti-settling agent uses fumed silica and polyamide wax to form a three-dimensional network structure in the system through hydrogen bonding and other interactions, providing thixotropy. The three work synergistically to ensure the long-term uniform and stable suspension of high-solids-content, high-density nanoparticles and wax powder in the system, preventing hard sedimentation during storage and ensuring batch stability and consistent application performance, which is crucial for commercial products.

[0019] Preferably, the functional acrylate resin used is M151 resin from Kaiping Zicai Chemical Co., Ltd. The molecular structure of M151 resin contains a large number of hydroxyl (-OH) functional groups, which can fully dissolve the odor-neutralizing photoinitiator used in this invention, ensuring that the odor-neutralizing photoinitiator in this invention does not precipitate even at low temperatures when the dosage is large. Experimental comparisons have shown that when the dosage of this odor-neutralizing photoinitiator is fixed, the larger the amount of resin used, the better the solubility stability of the photoinitiator. Table 1 below shows the relationship between the resin dosage and precipitation temperature when the dosage of this odor-neutralizing photoinitiator is 5%.

[0020] Table 1: M151 resin amount 0 5% 10% 15% 20% Precipitation temperature 15℃ 8℃ -3℃ -8℃ -10℃ The M151 resin is low in odor, low in viscosity, and has strong dilution ability. In this invention, it is used to replace monomers to adjust the viscosity of the paint and solve the problem of paint film odor caused by incomplete monomer reaction and residual residue. This resin has good elasticity and flexibility, and the resulting paint film has a certain tensile length, which can reach 100%. The resulting paint film can be folded back and forth 100 times without breaking.

[0021] Preferably, the modified polyurethane acrylate resin is a fluorosilicone modified trifunctional polyurethane acrylate resin; in this invention, LuCure8638 resin from Runao Chemical is used. The main chain of this fluorosilicone modified polyurethane acrylate resin is polyurethane, and the side chains are modified with fluorosilicone segments, thus exhibiting excellent flexibility. The trifunctionality provides good crosslinking density and low volume shrinkage, while also providing good wear resistance and scratch resistance. The fluorosilicone structures in the LuCure8638 side chains are incompatible with the main chain and have a lower specific gravity. This allows the fluorosilicone segments to naturally rotate and move to the coating surface during paint application, forming nano-synaptic fluorosilicone microstructures. This reduces the surface tension and coefficient of friction of the paint film, resulting in good wear resistance, scratch resistance, and stain resistance. This stain resistance is durable because the fluorosilicone structure is anchored in the three-dimensional network structure of the coating through acrylic double bonds. Compared to fluorosilicone additives floating on the paint surface, this significantly improves durability. Even after long-term use and surface wear, it still maintains good stain resistance and wear / scratch resistance. Experimental comparisons show that for improving scratch resistance and feel, a larger amount of LuCure8638 resin results in better scratch resistance and feel. However, there is a minimum threshold for improving graffiti resistance; below this threshold, the effect is not significant. The relationship between the amount used and graffiti resistance without organosilicon additives is shown in Table 2.

[0022] Table 2: LuCure 8638 resin amount 0 20% 40% 60% 80% Anti-graffiti No No No Good Very good Scratch resistance General General good Good Very good Very good Preferably, the leveling agent is TEGO® Glide 450; the defoamer is TEGO® Airex 920; the leveling agent is mainly used to improve leveling and prevent shrinkage cavities, and the defoamer mainly plays a defoaming role.

[0023] Preferably, the silicone additive is a UV-reactive silicone additive; in this invention, Silok® 8586 from Silok is used, which is a UV-crosslinkable, all-solid, alkyl-modified silicone slip agent. Under high temperature and UV conditions, it can crosslink with the corresponding resin, thereby giving the paint film permanent slip and scratch resistance, as well as unique anti-fouling and anti-graffiti functions. The greater the amount of this additive used, the better the scratch resistance, stain resistance, anti-graffiti, and feel.

[0024] Preferably, the 2,4,6-trimethylbenzoyl diphenylphosphine oxide is JRCure-1108 from Jiuri New Materials, i.e., a TPO photoinitiator; the 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone is JRCure-2959 from Jiuri New Materials. The TPO photoinitiator, as a solid initiator, has an absorption wavelength that matches the spectrum of LED lamps used for excimer pre-curing, making it suitable for excimer pre-curing. Furthermore, this initiator has a low odor and can be used as a deodorizing initiator through compounding. JRCure-2959 is an odorless, fast-curing, low-yellowing, and low-residue solid initiator.

[0025] Preferably, the wetting and dispersing agent is BYK Chemical's BYK-LP W 20084; the UV anti-settling paste is a hydrophobic fumed silica paste. The wetting and dispersing agent mainly functions to wet and disperse, and this additive is beneficial for the wetting and dispersion of wax powder and reducing viscosity, while also improving the flow and leveling properties of the paint; the UV anti-settling paste mainly functions to prevent settling.

[0026] Preferably, the wax powder is water-based polyethylene wax micro powder, mainly used to synergistically improve the scratch resistance of the paint film. In this invention, the wax powder used is PEW-0851 water-based polyethylene wax micro powder from Tianshi New Materials, which has high hardness, high melting point, good gloss uniformity, and affinity for both water-based and solvent-based systems, making it suitable for various water-based and solvent-based inks and coatings. The high-speed dispersion shear force makes it uniformly dispersed in the paint liquid, and it quickly floats and evenly arranges itself on the coating surface during paint application, providing the coating with excellent wear resistance, scratch resistance, and good hardness.

[0027] Preferably, the nano-sol is N-1680 nano-zirconia sol from Shenzhen Youyang, whose inorganic-organic hybrid structure formed after curing has extremely high scratch resistance and wear resistance. Zirconia possesses a unique polymorphic phase transition crystal structure. When subjected to external forces such as friction or impact, Will to The transformation, accompanied by a 3-5% volume expansion, absorbs energy and inhibits crack propagation, resulting in a fracture toughness exceeding 10 MPa·m¹ / ², significantly improving the material's fracture toughness and thus enhancing its wear resistance, scratch resistance, and flexibility. This phase transformation has a toughening effect, therefore nano-zirconia... As an inorganic aggregate in coatings, it can improve the hardness and strength of the paint film, and provide scratch resistance without affecting the flexural properties. In contrast, the addition of general inorganic fillers to coatings, while improving hardness, strength, and scratch resistance, also increases the brittleness of the paint film. The amount of N-1680 nano-zirconia sol used without silicone additives significantly improves hardness and scratch resistance, as shown in Table 3 below. N-1680 nano zirconium oxide sol amount 0 5% 10% 15% 20% Hardness 3B B F H H Scratch resistance General General Good Very good Very good Preferably, the product further comprises, by weight percentage, 0.1-0.5% polyamide wax. In this invention, BYK Ceraflour 920 is used. This wax powder is a surface-treated polyamide wax powder that exhibits excellent dispersibility and thixotropic effects in polar solvents and resin systems. It is specifically designed for high-end industrial coatings and has good compatibility with UV systems. The polyamide wax described is a thixotropic anti-settling agent with a microscopic needle-like or plate-like crystalline structure. When added to a coating system and properly shear-dispersed, these fine wax crystals swell and intertwine in the solvent and resin, forming a fragile yet effective three-dimensional network structure throughout the system. This network can physically lock in denser particles, such as nano-zirconia and wax powder, greatly slowing down or even preventing their settling due to gravity. Furthermore, when stationary, the network structure remains intact with high viscosity, preventing settling. During application, shear forces such as stirring, spraying, and rolling temporarily disrupt the network, reducing viscosity and facilitating leveling. After application, the shear force disappears, and the network quickly recovers, preventing wet film sagging, making it particularly suitable for vertical surface application. The microstructure formed by the polyamide wax may also have a subtle regulatory effect on the texture of the outermost surface of the paint film after curing, helping to enhance the matte finish and smoothness, resulting in a more uniform feel.

[0028] This invention relates to a low-odor, scratch-resistant, flexible, and skin-feeling UV excimer clear topcoat with a viscosity of 1200-2000 mPa·s / 25℃. During application and curing, it undergoes pre-curing under LED lights, followed by nitrogen-protected excimer curing, and finally, full curing using gallium and mercury lamps in synergy. The maximum energy requirement for full curing is 1200 mJ / cm². 2 .

[0029] This invention provides an odor-free, scratch-resistant, flexible, and bendable UV excimer skin-feel clear topcoat, and designs formulations for various embodiments and comparative formulations as shown in Table 4 below.

[0030] Table 4: Formulation Design of Examples and Comparative Examples (mass percentage %) Components Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 M151 resin (functional acrylate) 15% 25% 10% 18% 0% 15% LuCure 8638 (fluorosilicone modified trifunctional urethane acrylate) 53.5% 61.3% 51% 58.2% 63.5% 30% TEGO® Glide 450 (leveling agent) 0.3% 0.2% 0.3% 0.3% 0.3% 0.3% TEGO® Airex 920 (defoamer) 0.2% 0.2% 0.2% 0.2% 0.2% 0.2% Silok®8586 (UV reactive silicone adjuvant) 1.5% 1% 2% 2% 0% 0% JRCure-1108 (TPO) 1% 0.8% 1.2% 1% 1% 1% JRCure-2959 (odorless photoinitiator) 3% 2% 4% 4% 3% 3% BYK-LP W 20084 (wetting dispersant) 0.5% 0.5% 0.5% 0.5% 0.5% 0.5% Hydrophobic fumed silica slurry (UV anti-settling slurry) 3% 2.5% 3% 3% 3% 3% PEW-0851 (water-based polyethylene wax micro powder) 2% 1.5% 3% 2.5% 2% 2% N-1680 nano zirconium oxide sol 20% 5% 24.5% 10% 20% 0% Polyamide wax (such as BYK Ceraflour 920) 0% 0% 0.3% 0.3% 0% 0% HDDA (hexanediol diacrylate, traditional monomer) 0% 0% 0% 0% 5% 0% Bifunctional urethane acrylate (replace LuCure 8638) 0% 0% 0% 0% 0% 43.5% Common silicone leveling agent (replace Silok®8586) 0% 0% 0% 0% 1.5% 1.5% Total 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% The topcoats prepared according to Examples 1-4 and Comparative Examples 1-2 were applied, and the performance of the paint films of each example and comparative example was tested. The results are shown in Table 5 below.

[0031] Table 5 compares the performance test data of the examples and comparative examples: Test item / evaluation index Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Test standard / method Paint film VOC residue (mg / m³) <10 <10 <10 <10 >150 <10 GB / T 23986-2009 Low temperature storage stability (5℃, 30 days) No precipitation, easy to stir No precipitation, easy to stir No precipitation, easy to stir No precipitation, easy to stir Severe precipitation, not recoverable Mild precipitation, stirrable Visual observation, redispersibility Pencil hardness F B H H F 2B GB / T 6739-2006 Steel wool scratch resistance (500g, 50 times back and forth) No scratch Mild scratch No scratch No scratch Obvious scratch Severe scratch Visual observation and gloss retention rate TABER abrasion resistance (CS-10 wheel, 500g, 500 revolutions) Weight loss 18mg Weight loss 25mg Weight loss 12mg Weight loss 14mg Weight loss 35mg Weight loss 42mg ASTM D4060 180° back and forth folding times (without breaking) >100 times >200 times >80 times >100 times >90 times >200 times Self-made clamp, manual test T-bending (minimum bending radius R) R=1.0 mm R=0.5 mm R=1.5 mm R=1.2 mm R=1.8 mm R=0.5 mm GB / T 6742-2007 Stain resistance (oily pen, wipe after 24h) Erasable, no trace Erasable, no trace Easy to erase, no trace Easy to erase, no trace Erasable, no trace Cannot be erased Visual evaluation Artificial accelerated aging (QUV-B, 240h) ΔE 1.8 1.6 2.0 1.5 1.7 1.9 ASTM G154 Scratch resistance durability (repeat test 4 after 30 days at room temperature) Scratch slightly deepened Obvious scratch Almost no change Almost no change Complete loss of performance Initial difference, no change Compared with initial test As can be seen from the above, Comparative Example 1, which uses HDDA monomer to replace M151, has extremely high VOC residue and severe precipitation at low temperatures, making it completely unusable. This strongly demonstrates the irreplaceable nature of M151 resin in achieving "odor removal" and "stable dissolution of odor removal initiators." All examples showed excellent performance.

[0032] Comparative Example 2, without nano-zirconia, exhibited the lowest hardness (2B), the worst abrasion resistance, and extremely poor scratch resistance, despite having the best flexibility; this fully demonstrates that nano-zirconia sol (N-1680) is key to imparting excellent and balanced "hard and tough" damage resistance to the coating film. Example 3 performed best in all damage resistance tests, demonstrating the synergistic effect of high nano-zirconia content, reactive silicone, and wax powder.

[0033] All embodiments maintain good scratch resistance while exhibiting excellent bending performance (R<2mm, >80 folds), successfully achieving a balance of rigidity and flexibility. Among them, Embodiment 2 demonstrates extreme flexibility and is suitable for the most demanding bending scenarios.

[0034] Examples 3 and 4 both added reactive organosilicon, and the performance remained optimal after 30 days, demonstrating the key contribution of chemical bonding fixation technology to performance durability and solving the problem of migration failure of ordinary organosilicon.

[0035] All embodiments showed ΔE ≤ 2.0, indicating good resistance to yellowing.

[0036] Examples 3 and 4 both contain polyamide wax, and their condition after low-temperature storage is described as "easy to stir," which is superior to the "stir-stirred" state of other examples, demonstrating the additional improvement of polyamide wax on the stability of high solids content systems.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Anyone skilled in the art can readily implement the present invention based on the above description. However, any modifications, alterations, or variations made by those skilled in the art without departing from the scope of the present invention using the disclosed technical content are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, or variations made to the above embodiments based on the essential technology of the present invention are still considered part of the present invention.

Claims

1. A mild, scratch-resistant, flexible, bendable UV excimer skin-feel clear topcoat, characterized in that, By mass percentage, it includes the following components: Functional acrylic resins: 10-30%; Modified polyurethane acrylate resin: 40-80%; Leveling agent: 0.1-1%; Defoamer: 0.1-1%; Organosilicon additives: 0.1-4%; 2,4,6-Trimethylbenzoyldiphenylphosphine oxide: 0.5-2%; 2-Hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone: 0.5-7%; Wetting and dispersing agent: 0.3-1%; UV antisettling slurry: 2-5%; Wax powder: 1-5%; Nanosol: 5-30%.

2. The odor-neutralizing, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to claim 1, characterized in that, The functional acrylic resin used is M151 resin from Kaiping Zicai Chemical Co., Ltd.

3. The odor-free, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to any one of claims 1-2, characterized in that, The modified polyurethane acrylate resin used is a fluorosilicone modified trifunctional polyurethane acrylate resin.

4. The odor-neutralizing, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to any one of claims 1-3, characterized in that, The leveling agent used is TEGO® Glide 450; the defoamer used is TEGO® Airex 920.

5. The odor-neutralizing, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to any one of claims 1-4, characterized in that, The organosilicon additive used is a UV-reactive organosilicon additive.

6. The odor-neutralizing, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to any one of claims 1-5, characterized in that, The 2,4,6-trimethylbenzoyl diphenylphosphine oxide used is JRCure-1108 from Jiuri New Materials; the 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone used is JRCure-2959 from Jiuri New Materials.

7. The odor-free, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to any one of claims 1-6, characterized in that, The wetting and dispersing agent used is BYK Chemical's BYK-LP W 20084; the UV anti-settling slurry used is a hydrophobic fumed silica slurry.

8. The odor-free, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to any one of claims 1-7, characterized in that, The wax powder used is water-based polyethylene wax micro powder.

9. The odor-free, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to any one of claims 1-8, characterized in that, The nanosol used is UV solvent-free nanozirconia sol.

10. The odor-free, scratch-resistant, flexible, bending UV excimer skin-feel clear topcoat according to any one of claims 1-9, characterized in that, It also includes polyamide wax by weight percentage: 0.1-0.5%.