Pulping Characteristics
Corrugating medium paperboard grades produced from partially digested hardwood fibers provide high rigidity and crush resistance in corrugated board structures. Utilization of semi-chemical fluting incorporates wood pulp treated with chemical cooking liquor followed by mechanical fiberizing to retain high lignin content in cell walls. High residual lignin yields stiff paper sheets with superior flat crush and edge crush strength after corrugating operations.
Scope limits restrict this grade to semi-chemical medium paperboards, excluding fully bleached kraft papers and recycled waste-based fluting medium.
Compression Resistance
High stiffness and compression strength under load make semi-chemical medium essential for heavy-duty packaging applications. Incorporating semi-chemical fluting enhances the Concora medium test value and edge crush resistance of double-wall and triple-wall corrugated board. Residual lignin provides moisture resistance, preventing flute collapse when corrugated containers endure elevated humidity levels during cold chain storage.
Fiber stiffness allows corrugating machines to run at elevated line speeds without fracturing the web during flute forming nips. High energy absorption during compressive loading protects heavy industrial machinery and fresh produce during transit and warehouse stacking.
Corrugating Performance
Papermaking parameters like refining energy and moisture profile control sheet runnability on high-speed corrugators. Using semi-chemical fluting ensures uniform glue absorption and flute profile formation during roll nip engagement. Structural rigidity maintains box stacking strength across challenging agricultural and industrial supply chains.