International Organization for Standardization · 2017
← All references · ISO & EN Standards
The reference dye-stain seal-quality test for sealed anodic coatings. A dye solution is applied to a prepared coating surface after acid pre-treatment; the resulting stain intensity correlates with sealing quality (well-sealed coatings reject the dye and show minimal stain; poorly sealed coatings absorb dye into the porous structure and stain visibly). Reported on a 0-5 scale. Used internationally alongside the admittance test (ASTM B457) for sealed anodize QC.