Waterborne epoxy resins can be divided into anionic and cationic resins. Anionic resins are used for anodic electrodeposition coatings, while cationic resins are used for cathodic electrodeposition coatings. The main characteristic of water-based epoxy resin is its excellent anti-corrosion performance. In addition to being used for automotive coatings, it is also used in fields such as medical devices, electrical appliances, and light industrial products.

Waterborne epoxy resin refers to a stable dispersion system prepared by dispersing epoxy resin in the form of particles or droplets in a dispersion medium with water as the continuous phase. Due to the fact that epoxy resin is a linear thermosetting resin, a water-based epoxy curing agent must be added before construction to undergo chemical crosslinking reaction at room temperature. After curing, the epoxy resin changes its original soluble and fusible properties into an insoluble and non fusible spatial network structure, demonstrating excellent performance. Waterborne epoxy resin coatings have many advantages in addition to solvent based epoxy resin coatings:
Firstly, it has strong adaptability and high adhesion to numerous substrates. After curing, the coating film has excellent corrosion resistance and chemical resistance, as well as small shrinkage, high hardness, good wear resistance, and excellent electrical insulation performance;
Secondly, it has good environmental performance and does not contain organic solvents or has a low content of volatile organic compounds, which will not cause air pollution, thus meeting the current requirements of environmental protection;
Thirdly, it is truly water-based, using water as a dispersing medium, which is inexpensive, odorless, non flammable, and greatly improves the safety during storage, transportation, and use;
Fourthly, it has good operability. The water-based epoxy resin coating has good construction performance, and the construction tools can be directly cleaned with water. It can cure at room temperature and humid environments, with a reasonable curing time, and ensures a high cross-linking density. This is incomparable to conventional waterborne acrylic coatings and waterborne polyurethane coatings. Waterborne epoxy resin, with its outstanding performance advantages, enables the prepared waterborne epoxy resin coatings to also have excellent performance, thus playing an increasingly important role in the waterborne product family. Experts believe that waterborne epoxy resin has a very broad prospect in today's environmental protection.