###### Abstract  
The purpose of this paper was to discuss the best coating technology of water-based coatings containing microcapsules, and the anti-aging and self-repairing properties of water-based coatings containing microcapsules. Urea-formaldehyde encapsulated Nippon water-based emulsion microcapsules were prepared, and water-based coatings containing microcapsules were prepared. The optical and mechanical properties of the coatings under different coating technologies were investigated. Under the best coating technology, the aging resistance and self-repairing performance of the coating film were investigated. Experimental results showed that coating technology had no effect on color aberration of the coating film. The coating technology with two coats of primer, three coats of topcoat, addition of microcapsules into primer, had excellent glossiness, shock resistance of 12.0 kg\(\cdot\)cm, adhesion of 0 grade, and fracture elongation of 26.3%. Compared with the coating film without microcapsules, the coating with microcapsules had better aging resistance and self-repairing property, and the self-repairing rate was about 20.0%. Compared with the paint film with Dulux water-based emulsion microcapsules, the paint film with Nippon water-based emulsion microcapsules had a higher self-repairing rate. This study provides a technical basis for self-repairing water-based coatings. microcapsule; coating technology; water-based coatings; properties +
Footnote †: journal: Applied Sciences  
(PUF)-based microcapsule. It was found that self-healing was realized through two mechanisms. Firstly, the chain migration was induced at the defects of the modified coating. Secondly, swelling hydrogels existing in PUF shells were cross-linked by various polymer-polymer interactions. [PERSON] et al. [18] embed hexamethylene diisocyanate (HDI) and AIE luminogens (AIEgens) in microcapsules to achieve self-repairing and self-reporting functions in the polymer coatings. They demonstrated that the dual-function microcapsules had a good application prospect in different polymer matrices, and the content of AIEgens can even be reduced to 0.05 wt%. [PERSON] et al. [19] prepared dual microcapsules containing polyamines as multifunctional triggers and epoxy monomers dyed with pH indicators. The results showed that, with comprehensive warning, intelligent materials showed high repair performance for dynamic impact damage, and the repair efficiency can reach 100% without external intervention. [PERSON] et al. [20] prepared long-acting self-repairing liquid repellent coating by mixing silicone oil containing UV-responsive microcapsules with commercially available water-based polysiloxane emulsion. The liquid-repellent coatings can withstand different harsh environments and have good long-term self-repairing function. [PERSON] et al. [21] used pH-responsive microcapsules and TiO\({}_{2}\) nanoparticles to develop an environment-responsive self-repairing water-based super-hydrophobic coatings. These coatings can easily form superhydrophobic surfaces on various substrates under ultraviolet irradiation. More importantly, even if they are damaged mechanically or polluted by oil, they can recover their super-hydrophobicity and self-cleaning ability under ultraviolet light. In addition, this superhydrophobic coating also has anti-corrosion and anti-icing capabilities in extreme natural environments. The above research shows that the self-repairing application of microcapsules is very extensive and the application prospect in the field of coatings is very broad. Urea-formaldehyde resin with good compactness was selected as the shell material [22], and Nippon water-based acrylic resin with the same composition as the coating base was selected as the core material, because the water-based acrylic resin is safe and stable, and has good film forming property [23; 24]. More importantly, it does not introduce heterogeneous components, which was convenient for analysis and easy to operate, and was conducive to improving the interfacial compatibility of the coating.