Phosphating prior to coating for steel is usually needed. In this paper, an innovative cleaner production
has been developed for steel surface treatment using Zn–Mn phosphating solution in which there was no
nitrite. The mass of the Zn–Mn layer deposited in this new process was about 1.1 gm2 when the
temperature ranged from 3 to 35 C. The corrosion time for the color phosphating layer in the copper
sulfate spot test was in the range of 72–145 s. Adhesion test showed that the coating layers achieved
a higher adhesion load than those produced by conventional methods. Washing using water was not
necessary in this cleaner phosphorization, which usually follows phosphorization in traditional processes
of steel phosphorization. Consequently, wastewater discharge was reduced greatly.