What are the characteristics of silane treatment on metal surface?

Silanization treatment agent is a process of surface treatment of metal or nonmetal materials with organosilane as the main raw material. Compared with traditional phosphating, silylation treatment has the following advantages: no harmful heavy metal ions, no phosphorus and no heating. The silane treatment process does not produce precipitation, and the treatment time is short and the control is simple. There are few treatment steps, so the surface adjustment process can be omitted, and the bath solution can be reused. Effectively improve the adhesion of paint to the substrate. It can process various substrates such as iron plate, galvanized plate and aluminum plate in line.

However, the above two treatment methods have great defects. In terms of environmental protection: phosphating contains heavy metal ions such as zinc, manganese and nickel, and contains a lot of phosphorus. Chromium passivation treatment itself contains serious toxic chromium, which can not meet the national environmental protection requirements for painting industry. In terms of use cost, a large amount of phosphating slag will be produced during phosphating treatment, and a slag removal device is needed to match it. Moreover, the phosphating temperature is mostly 30-50℃, so auxiliary heating equipment and heat source are needed to heat the phosphating tank. At the same time, after phosphating and chromium passivation, a large amount of overflow water is needed to wash the workpiece. Due to the defects of environmental protection and use cost, a new coating pretreatment technology with environmental protection, energy saving, low emission and low use cost has become a hot spot for technicians in the industry at home and abroad. The United States began the theoretical research of metal silane pretreatment technology in the 1990s, and Europe began the exploratory research of silane in the mid-1990s. At the beginning of this century, under the great pressure of environmental protection in China, major research institutions and production enterprises also began to study silane.