During sampling, although the same sandblasting and coloring process was applied, the final appearance showed clear inconsistency. The black color depth and sandblasted texture differed between the AS outer shell and the PP pump, even under identical process parameters.
This occurred because AS and PP respond differently to sandblasting. AS tends to form a denser surface, while PP develops a rougher micro-texture. These differences affect light reflection and pigment adhesion, making it difficult to achieve a uniform appearance across mixed-material components.
Based on this evaluation, our team recommended switching to a single-material solution, allowing the sandblasting process to interact consistently with the surface. This adjustment significantly reduced visual variation and improved the stability of the final cosmetic packaging appearance.
From this case, we concluded that mixing AS and PP significantly increases the risk of visual inconsistency in sandblasted pump heads. For cosmetic packaging projects with high appearance requirements, a single-material structure is the more reliable solution.
At Auber Packaging, we help brands evaluate materials and surface processes early in development to avoid costly revisions during sampling. If you are working on cosmetic packaging with special finishes, feel free to connect with us before finalizing your design — early decisions often define the final result.
