3D coating resin is a type of liquid polymer that is used to create a clear, glossy, and durable finish on 3D printed objects or other surfaces. It is often applied using a brush, spray, or dip method, and then cured using UV light or heat to harden and solidify the coating. This resin is typically made from a mixture of epoxy, polyurethane, or acrylic compounds, and is designed to protect the surface of the object from scratches, UV radiation, and other environmental factors. 3D coating resin can also be tinted or colored to create custom finishes or effects.