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The differences between water-based coatings and solvent-based coatings can be explained from the following perspectives: A. Differences in the coating system 1. Different resins – the resins used in water-based coatings are water-soluble and can be dispersed (dissolved) in water； 2. Different diluents (solvents) are used: for water-based coatings, DIWater (deionized water) can be added in any proportion to thin them out, whereas solvent-based coatings can only be diluted with organic solvents such as xylene, butyl acetate, and nail polish remover. B. Different requirements for paint application: 1. Regarding the application environment, the freezing point of water is 0°C; therefore, water-based paints cannot be applied when the temperature is below 5°C, while solvent-based paints can be applied at temperatures above -5°C, though their drying speed will slow down and the time between coats will increase ； 2. Regarding application viscosity, water has a poor effect on reducing viscosity; it is relatively troublesome to thin water-based coatings in order to lower their viscosity (a decrease in viscosity significantly reduces the solid content of the coating mixture, affecting its covering power and increasing the number of application coats required). Solvent-based coatings are easier to adjust in terms of viscosity, and viscosity constraints also influence the choice of application method ； 3. Regarding drying and curing, water-based paints are more delicate; they cannot cure properly in conditions of high humidity or low temperatures, which results in an extended drying time. However, even when the temperature is increased, water-based paints require a gradual rise in temperature – exposing them suddenly to high temperatures can cause the water vapor inside the paint to escape, leading to pinholes or even large-scale bubbling. This is because water-based paints use only water as a solvent, and there is no mechanism for gradual evaporation. In solvent-based coatings, the solvents used as thinners are organic solvents with different boiling points, resulting in multiple evaporation rates; therefore, similar phenomena do not occur when they are baked in a high-temperature area after flash evaporation (the period of drying after application but before entering the oven). C. Differences in the decorative properties of the film after formation C-1. Variations in gloss level 1. Solvent-based coatings allow for control over the fineness of pigments and fillers through grinding; they do not tend to become coarser over time during storage. The gloss of the coating can be adjusted by adding resins to control the pigment-to-resin ratio, as well as by using additives such as matting agents. The resulting gloss levels can range from matte, dull, semi-dull to high-gloss. The gloss of car paint can exceed 90% ； 2. Water-based coatings do not have as wide a range of gloss levels as oil-based coatings; their ability to achieve high gloss is limited. This is due to the water present in water-based coatings, which acts as a diluent, and its tendency to evaporate makes it difficult for such coatings to achieve a gloss level of over 85%. C-2. Different color expressiveness: 1. Solvent-based coatings offer a wide range of options for pigments and fillers, which can be either inorganic or organic; thus, various colors can be created, resulting in excellent color expressiveness ； 2. The range of pigments and fillers available for water-based coatings is limited; most organic pigments cannot be used. Due to the limited color palette, it is difficult to achieve a wide range of colors similar to those available in solvent-based coatings. D. Water-based coatings do not contain flammable organic solvents, making their storage and transportation relatively safe. In the event of contamination, they can be rinsed and diluted with large amounts of water. However, there are temperature requirements for the storage and transportation of water-based coatings; at temperatures below -5°C, insulated conditions are necessary for storage and transportation, otherwise problems such as emulsion breakdown may occur. E. Functional superiority: Solvent-based coatings are mostly organic products, and these organic products suffer from issues such as chain breakage and carbonization at high temperatures; currently, the maximum temperature tolerance of such organic products is no more than 400°C. Special high-temperature resistant coatings that use special inorganic resins in water-based coatings can withstand temperatures of over a thousand degrees. For example, the ZS series of high-temperature resistant water-based coatings not only possess the corrosion and oxidation resistance typical of conventional coatings but can also endure high temperatures for extended periods, with a maximum tolerance of up to 3000°C – a level that solvent-based coatings cannot achieve. G. Differences in safety and environmental protection: Solvent-based coatings pose fire and explosion hazards during production, transportation, storage, and use; especially when applied in enclosed spaces, they can easily lead to asphyxiation and explosions. At the same time, organic solvents can also cause certain harm to the human body. The most famous case is the toluene carcinogenesis case; toluene is no longer allowed to be used. Solvent-based coatings have high VOC levels; conventional products can have levels as high as over 400. As a result, companies face significant environmental and safety challenges when producing and using such coatings. Water-based coatings are environmentally friendly and safe throughout their production, transportation, storage, and use stages (with the exception of some fake water-based coatings produced by unregulated manufacturers), and they make a significant contribution to policies aimed at energy conservation, emission reduction, as well as safety and environmental protection.