| 摘要 |
In a phosphating process in which the metal surface is treated with a solution of phosphoric acid, a dibasic phosphate and an accelerator which is a nitrated aromatic derivative having at least one free phenol radical, the nitrated organic derivative is dissolved in a nonionic surfactant which is the reaction product of ethylene oxide and a hydrophobic base, before being combined with the phosphoric acid and dibasic phosphate to form the phosphating solution. In this manner, a more homogeneous composition is obtained than has heretofore been possible when the nitrated organic derivative per se, has either been mixed with the phosphated compounds to form a concentrate composition or has been added to the aqueous phosphating solution.
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