The role and requirements of the topcoat UV vacuum plating topcoat is a coating applied on vacuum coated metal, which has a protective effect on the coating and a certain decorative effect. Therefore, the topcoat requires good adhesion to the metal coating, and has sufficient performance to resist external friction, scratching, scratching and the like, and provides certain resistance and barrier properties. In addition, most of the topcoats or intermediate coatings require color modification, and the pigment coating wettability requirements of the entire coating system are also very high.

The formulation of the topcoat is different from the primer of the UV vacuum plating. In order to ensure the mechanical properties of the coating, the UV coating of the casing is generally compatible with a resin with a high degree of functionality. In addition, considering the additive color, it will be allowed. Add some ultra-high-functionality resin to improve the wear resistance. In addition, for the convenience of adding the pigment to the system, the resin with good finishing properties is also preferred, such as imported 6071 of Changxing Chemical and UA378 of domestic Qianchen material. Europe and the United States also have good material selection. In terms of additives, a small amount of HEMA assisting properties can be used under the premise of ensuring performance.