How to prevent dust generation in die-cutting production?

Dust and loose fibers are terms used in flatbed die-cutting, which refers to the generation of loose particles and fragments, as well as the accumulation of fiber filaments adhered to the die-cut edges of paperboard. It is important to note that these particles and fibers mostly come from the surface of the die-cut paperboard. Three aspects need to be considered:

How to perform the flatbed die-cutting process? To accurately describe the flatbed die-cutting process using steel cutting dies, it is defined as a progressive process consisting of two steps. The first step is called "burst penetration," and the second step is called "burst separation."

In the synchronous die-cutting process, the full length of the cutting blade is in contact with the surface of the die-cut material. During the die-cutting process, the cutting blade applies pressure to the paperboard material. Although die-cutting is described as a cutting process, more precisely, it is a process of paperboard fracturing under pressure. As the blade penetrates the paperboard towards the anvil pad, the paperboard surface is compressed, stretched, and squeezed. Eventually, the surface of the paperboard can no longer withstand the pressure, resulting in a "burst penetration" that fractures the paperboard.

The use of the term "burst" to describe the surface rupture of the paperboard is accurate because the cutting blade exerts strong tensile and compressive forces on the paperboard, causing the surface along the cutting blade to collapse. After the surface rupture of the paperboard, the sharpness of the cutting blade plays a less significant role in comparison to the previous step, as the double beveled angles of the tool/wedge convert vertical pressure into lateral movement. As the tool penetrates into the paperboard, the angled surface of the tool pushes the paperboard vertically towards the sides.

Under intense fracturing pressure, the paperboard is completely torn before the tool and anvil pad make contact. This "burst separation" process consists of surface rupture, tool wedging, and paperboard fracture. Even under suboptimal production conditions, as long as equipped with sharp steel cutting tools, smooth liner pads, and optional die-cutting setup systems, the paperboard can still fracture under intense bursting pressure.

What causes the generation of dust and loose fibers? Dust and loose fibers are caused by damaged cutting blades, which exert excessive force impacting the surface of the liner pad. This causes the cutting blade to widen, significantly increasing the compressive and tensile forces applied to the paperboard surface. The paperboard is further compressed, and tension gradually increases until it fractures. This excessive force results in the production of fragments and "dust" particles.

As the pressure increases on the cutting tool, further compression forces dull the cutting blade. The degree of compression and stretching of the paperboard exceeds the normal range, causing the surface to rupture into three pieces. From this description of the process, we can conclude that dust and loose fibers come from the surface of the paperboard, and their generation is due to the progressive damage of the cutting blade.

How to avoid the generation of dust and loose fibers? The method to avoid this issue is to maintain the good condition of the steel cutting blade. There are several methods to choose from, and in practical operation, one or more methods can be used simultaneously.

These methods include: using softer or "lower thickness" liner pads; calibrating the flatbed die-cutting machine to prevent excessive force; calibrating and balancing the pressure on the die-cutting tools to ensure precise "Z-axis control" of the blade; operating critical tools in a "floating knife" manner in the production planning; and integrating double paperboard and spot patch technology precisely into the combined patching process to achieve uniform die-cutting.