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Ruodin: ruodin is a mixture of thiourea derivatives, surfactants and acid cleaning antifogging agents. There are many kinds of ruodin. It is a very effective acid cleaning inhibitor and widely used in parts rust removal.

Note: the effective component of ruodin is DIO toluene thiourea. In addition, auxiliaries must be added to produce wetting effect, which helps the active ingredients to mix with the acid solution, not float on the liquid surface, and form a foam, acid mist on the acid surface.