Fibre Composition
Multi-ply packaging substrate produced from recovered paper fibers provides structural packaging material for non-contact applications. Packaging classification identifies recycled cartonboard as a paperboard grade manufactured primarily from post-consumer or post-industrial recovered paper stocks organized into distinct functional plies. Outer surface coatings improve printability over grey or white fiber backings.
Structural Performance
Papermaking facilities re-pulp recovered paper products, screening out contaminants such as plastic films, adhesives, and staples before forming sheets on multi-wire machines. Top plies receive higher-grade recovered fibers or bleached virgin pulp to create a clean background suitable for clay coating application. Middle and back plies utilize lower-cost mixed paper stocks, building thickness and bending stiffness at lower production costs.
Recycled fibers undergo shortening and hornification during repeated repulping cycles, lowering individual fiber strength compared to virgin wood pulps. Mills compensate for lower intrinsic fiber strength by increasing basis weight or adding dry strength starches during stock preparation. Recycled sheets exhibit good stiffness and crease formation, serving standard folding carton applications across retail packaging sectors.
Contamination Boundary
Chemical compliance protocols monitor mineral oil hydrocarbons and heavy metal residues to prevent migration into sensitive packaged products. Barrier coatings or functional inner liners are required when packaging dry foods to prevent contaminant transfer from recycled fibers. Recycled cartonboard delivers sustainable material choices for commercial packaging while requiring strict quality monitoring.
