Shenhua Printing Plate Knife Plate Spring Pad: A Packaging Solution for Long-Distance Cross-Border Transportation to Ensure Die-cutting Strength and Structural Integrity

Cross-border long-distance transportation packaging mostly uses high-strength corrugated paper, reinforced composite cardboard, and anti-collision structural cardboard. It not only needs to ensure the packaging can withstand pressure and resist impact, but also requires the die-cutting outline to be regular, the structural cutting edges to be free of burrs, and the cardboard not to crack or delaminate. Conventional shock pads either have insufficient pressure resulting in incomplete die-cutting and too many connection points, or have too high hardness causing the cardboard cutting edges to burst and the crease pattern to collapse, directly reducing the transportation safety and the qualified rate of the finished products. Deephua Printing Materials, in response to the die-cutting characteristics of long-distance transportation packaging, has launched special shock pads for structural preservation, achieving the dual goals of complete cutting and complete paperboard structure integrity.

In terms of material matching, a balanced rebound formula with medium to high hardness is adopted, with the Shore A hardness controlled within the range of 60–70, taking into account both the supporting strength and the buffering reserve. When die-cutting thick and hard cardboard, it can provide sufficient cutting pressure while avoiding the cracking of the cardboard edges and the collapse of the internal corrugations caused by rigid impact. By adjusting the material cross-linking density, the rebound curve of the shock pad becomes more gentle, the pressure release is uniform, and the instantaneous stress concentration on the paperboard around the knife line is reduced, fundamentally reducing the probability of cardboard cracking and delamination.

In terms of structure and size design, based on the thickness of commonly used paperboard for cross-border heavy-duty packaging, a standard thickness sequence of 2.0–3.5mm is launched, with a thickness tolerance of ±0.03mm, ensuring the consistency of the overall die-cutting pressure and eliminating the phenomena of local cutting failure and local collapse. The edge of the shock pad is processed by precise cutting and sealing, which is not prone to shedding debris or shedding fibers, and will not contaminate the packaging and production environment. An enterprise mainly engaged in the packaging of large-sized goods from Europe and America used it, and the cracking rate of the cardboard die-cutting decreased from 7.2% to 0.4%, the rework rate of connection points dropped by 90%, the packaging pressure resistance test qualified rate increased simultaneously, and successfully met the strength standards for cross-border logistics packaging.