METHOD OF PHOSPHATING METAL SURFACE WITH ZINC PHOSPHATE

• Main Authors: SHIRAISHI, SHOJI, SHIRAHATA, SEIICHIRO, TOKUYAMA, AKIO, SOBATA, TAMOTSU
• Format: Patent
• Language: English; French
• Published: 18.05.1999
• Edition: 6
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

To treat an iron-based, zinc-based, and an aluminum-based surfaces etc. with zinc phosphate using the same solution, a treating solution is adjusted in concentrations so as to contain a simple fluoride in a range of 200 ~ 500 mg/l upon converting into a HF concentration and to contain a fluoride complex in a range shown in the following formula; and also, it is adjusted in an active fluorine concentration so as to be 15 ~ 130 .mu. A at a value indicated by a silicon electrode meter. Instead of such adjusting, aluminum ions in the treating solution is precipitated in an outside of a treating bath to separate them from the treating solution and then, this treating solution may be returned into the treating bath.