Barrier Film MFC Layer PHA Primer Aluminum Oxide Delamination

The patent introduces an intermediary layer between the PVOH tie layer and the metallization layer to prevent direct contact and potential delamination. This intermediary acts as a buffer that maintains adhesion while protecting against moisture-induced dissolution of PVOH, thereby resolving the contradiction between achieving strong adhesion and preventing delamination under humid conditions.

The patent employs a sacrificial or replaceable intermediate layer that can be easily removed or replaced if delamination occurs. This layer serves as a temporary protective measure that sacrifices itself to prevent failure of the entire packaging structure, allowing the main functional layers to remain intact.

The patent introduces an intermediary barrier layer between the metallization layer and the external environment. This intermediary layer maintains the excellent barrier properties of the metallization against gases and moisture while preventing direct contact between metals and soil, thereby blocking the leaching pathway and eliminating environmental contamination.

The patent extracts or removes the metallization layer from direct contact with the environment by placing it within the multi-layer structure where it is isolated from external exposure. The functional barrier properties are retained through the layered construction, while the harmful metal leaching is eliminated by taking out the metallization from the harmful environmental interface.

The patent segments the packaging structure into distinct functional layers, with the metallization or barrier layer separated from the recyclable paperboard substrate by intermediate and protective layers. This segmentation allows the barrier function to be maintained while enabling the paper-based components to be easily separated and recycled independently, resolving the contradiction between achieving superior barrier properties and maintaining recyclability.

The patent designs the packaging structure so that non-recyclable or difficult-to-recycle components (such as metallization layers or plastic coatings) can be easily discarded or removed, while the valuable recyclable paperboard substrate is recovered and reused. This approach maintains the necessary barrier properties through the discarded layers while maximizing the recovery and reuse of sustainable materials.