The surface treatment of the steel plate trash can is to improve the ornamentation, and the other is to increase the anti-corrosion ability of the base material of the trash can. Among them, the surface spray treatment is one of the commonly used process methods in the production of trash bins.

Electrostatic spraying is a surface treatment method for spraying plastic powder on parts. Plastic spraying, or electrostatic powder spraying, is a treatment process in which the plastic powder is charged by an electrostatic generator, adsorbed on the surface of the workpiece, and then baked to melt the powder and adhere to the surface of the workpiece.

There are four major steps in the spraying process. The first is "pretreatment", which removes oil, dust, and rust on the surface of the workpiece, and generates a layer of corrosion-resistant and can increase the adhesion of the spray coating "phosphate layer" on the surface of the workpiece.

Then there is "electrostatic spraying", the powder coating is evenly sprayed on the surface of the workpiece, and special workpieces (including positions that are prone to electrostatic shielding) should be sprayed with a high-performance electrostatic spraying machine. The second is "high temperature curing". The powder coating on the surface of the workpiece is heated to a specified temperature and kept for a corresponding period of time to melt, level, and solidify, so as to obtain the surface effect of the workpiece we want. At the end is "decorative treatment", so that the workpiece after electrostatic spraying can achieve a certain special appearance effect, such as various wood grains, patterns, and brightness.

The surface of most galvanized steel sheets has generally been passivated, but it is difficult to tell with the naked eye whether it has been processed. It is usually required to be sprayed after alkaline washing. However, the adhesion of the passivation film after alkaline washing will be reduced after spraying. In this case, it is recommended to wash and dry before spraying without oil stains.