Interply Delamination Energy Thresholds during High Speed Converting of Recycled Paperboard Grades
Matching dynamic Scott Bond energy above 120 J/m² prevents high-speed folder-gluer delamination and reduces net carton cost through lower line scrap.
GT2 Paperboard
Grade Classification
Recycled folding boxboards coated on one side and manufactured with a pigment-coated white top layer over a grey chipboard middle layer form an established packaging substrate class across European converted carton markets. Packaging specifications designating GT2 paperboard define a recycled grade containing specific proportions of secondary fibre layers with standard coating coat weight limits. This board grade provides an economical barrier-coated packaging stock for consumer goods where high white appearance on the outer print face must coexist with secondary fibre economics in the structural core.
Structural Layering
Multi-ply cylinder or former web combination machines build this recycled board by depositing distinct stock suspensions across multiple forming positions. In GT2 paperboard production, virgin pulp or high-grade white deinked pulp forms the printable top layer, while lower grade mixed recovered paper forms the bulky middle plies that deliver bending stiffness. The grey back layer consists of sorted post-consumer recovered paper, giving the reverse side its characteristic grey shade without compromising structural integrity or creasing performance.
Convertibility Performance
Scoring and creasing operations require balanced ply adhesion to prevent delamination during high-speed carton erecting. Inadequate internal bond strength in GT2 paperboard causes cracking along score lines during folding, which weakens the finished box structure under stacking loads.