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In the early 1990s, the American Shell Company first developed a two-component water dispersion epoxy resin system, which is a third-generation water-based epoxy system. This epoxy resin system has a distinctive feature, namely: Both the epoxy resin and the curing agent are designed as water dispersions. The curing agent is synthesized into a type with a certain degree of hydrophobicity (i.e. lipophilicity, this technology has always been very confidential), and has the same or close HLB value as the epoxy resin. This changes the water-soluble state of the past amine curing agent and improves the compatibility with the resin. Epoxy resin improves hydrophilicity, self-emulsification. Another major improvement in water-dispersed epoxy systems is: Hydrophilic nonionic surfactants are attached to the molecules of the resin and curing agent. This new technology effectively reduces the amount of surfactant, and there is no free surfactant in the system. This reduces the sensitivity of the coating to water-based solvents and increases the stability of the system. Since the two components are both dispersions, after mixing, the two components are evenly dispersed in the water phase in a particle state, and a demulsification process occurs. This process occurs very quickly, such as a company's products.: After the epoxy emulsion (particle size 0.1-0.2 μm, pH 7.5) and self-emulsifying curing agent (particle size 0.1 μm, pH 11) are measured according to the formula requirements, the viscosity before mixing is 26 mPa·s and 1200 mPa·s respectively, and the viscosity after mixing is 30 mPa·s, pH 9. The lower the viscosity, the easier it is to mix evenly. The smaller the particle size, the denser the paint film obtained, and the high OH value avoids flash corrosion on the steel surface. Therefore, when the coating film dries, no flash corrosion occurs on the steel surface, and the resulting paint film is very uniform after curing. The water resistance and chemical resistance of the paint film indicate that there are no free small molecules in the paint film. The performance of the paint film is close to that of the solvent-based epoxy paint film, which improves the economic value of water-based epoxy. Due to technical reasons, this result has not been publicly reported so far. This type of self-emulsifying epoxy curing agent has been successfully developed in China by Zhejiang Anbang New Materials Development Co., Ltd. and has been industrialized. Water-based two-component epoxy coatings have many applications on the market, such as high-performance alkali-resistant sealing primers, equipment anti-corrosion primers, industrial factory floor paints, transportation primers, automobile maintenance primers, and industrial maintenance paints. Therefore, room temperature curing water-based epoxy coatings will have great development prospects, and many new varieties have been researched and developed abroad. There is a certain gap between domestic research and application in the field of new water-based epoxy dispersion systems and foreign countries. The future development direction is to improve the cross-linking degree, hardness and flexibility of coatings, shorten the curing time, improve mechanical properties and expand application areas. While developing water-based epoxy emulsions, the development of water-based epoxy curing agents, an important partner of epoxy emulsions, should not be ignored. The earliest synthesis process of water-based epoxy curing agent. Since the curing agent contains a large amount of free surfactant, it solidifies with the water-based epoxy resin to form a film. They have poor compatibility with the epoxy resin, short service life, and poor water resistance. Since then, a second generation water-based epoxy curing agent has been developed, but it also has certain limitations.