Phosphorus-free environmental protective film agent

Phosphorus-free conversion film (vitrification) is a kind of chemical treatment agent that uses impregnation method or spray method to treat the metal surface, and forms a golden yellow to blue purple protective film on its surface. The color of the film changes according to the film weight, material and temperature. This film has excellent corrosion resistance, can improve the coating adhesion, and is an excellent coating pretreatment agent. Phosphorus-free conversion film is suitable for surface treatment of various cold rolled sheets, galvanized sheets, aluminum and aluminum-related metals, especially for powder coating. This agent is phosphate free, heavy metal free, slag free, normal temperature operation, convenient sewage treatment, energy saving and environmental protection.

Working principle of phosphorus-free conversion film:

The hydrolysis reaction of fluorozirconic acid is mainly used to form an amorphous oxide with stable chemical properties on the surface of the metal substrate. By adding oxidant and chelating agent, the hydrolysis reaction is promoted, and the metal surface film with good performance is obtained.

The main compound of the surface treatment film obtained by this technology is ZrO2, and the obtained film is the oxide and hydroxide of Zr.

Advantages of phosphorus-free conversion film

1. It is an upgrading product of traditional phosphating solution

2. No phosphorus, no heavy metal, simple wastewater treatment, environmentally friendly

3. No sludge

4. Reduce energy consumption and cost

5. Suitable for cold rolled sheet, hot rolled sheet, galvanized sheet, aluminum, stainless steel and other materials