Substrate Specification
Double-ply or multi-ply linerboard manufactured primarily from recovered paper fibres provides an economical outer facing for corrugated shipping containers. In the production of recycled testliner, mills use recycled corrugated boxes and mixed paper to form the sheet, often adding a high-quality surface ply to improve printability. This paperboard grade is chosen for applications where cost efficiency is prioritized over maximum tensile performance.
Strength Properties
Physical resistance of this board relies on starch spraying and chemical additives to compensate for the shorter fibre lengths of recycled pulp. Since recycled testliner has lower burst strength than virgin paperboard, mills must increase its thickness or basis weight to achieve the required edge compression resistance. This adjustments ensures that the final boxes meet the structural standards required for parcel transit.
Converting Usability
High moisture sensitivity is a characteristic of this material that must be managed during the corrugating process. Applying recycled testliner requires careful control of adhesive application and heat exposure to prevent warp and delamination on the corrugator. This attention to process parameters ensures that converters produce flat, stiff sheets that run smoothly through high-speed die-cutting and folding machines, resulting in clean edges and precise folding alignment that prevents automated packaging lines from jamming during cartoning.