It is regarded that good anti-corrosivity of conventional wash primer results from complex reaction between OH in polyvinyl butyral and chromium ion in the presence of phosphoric acid in addition to passivity effect of zinc chromate.
It was found in this study that specific reaction between borate compounds and polyvinyl butyral in the presence of phosphoric acid gave excellent anti-corrosive film without environment pollution, which is superior to the conventional wash primer.
The specific reaction was investigated by means of infrared spectroscopic analysis, X-ray fluorometry, electron microprobe X-ray analysis.
As the results, the complex reaction of polyvinyl butyral with borate compounds, and the specific behavior to the substrate by the complex was found. Natural electrode potential and polarization resistance of the film also showed the evidence.
View full abstract