Grade Substitution Shipped under an Unchanged Product Name
Unannounced paper grade substitution alters structural fiber bonding and surface chemistry, demanding dockside physical and chemical testing before press loading.
Die-Cutting Blade Dulling
Edge Degradation
Loss of sharpness in the cutting rule occurs when the steel edge is worn down by abrasive components within the paperboard or by the impact against the matrix. The die-cutting blade dulling increases the required pressure for a clean cut and leads to poor edge quality. It is a major factor in determining the length of a production run before the tooling must be replaced.
Substrate Factor
Coatings containing high amounts of mineral fillers such as titanium dioxide or clay accelerate the wear on the tool. These hard particles act as an abrasive that slowly grinds away the fine tip of the blade. Recycled fibres often contain minute fragments of grit or glass that further contribute to the erosion of the steel.
Production Consequence
Resulting defects include the formation of dust and loose fibres that can interfere with the subsequent printing or gluing stages. As the die-cutting blade dulling progresses, the machine operator must increase the cutting force which can cause the board to crush or deform. This degradation eventually results in whiskers or hairy edges on the finished carton.
Proper selection of blade steel and the use of cushioned ejection rubbers can extend the life of the tool but the abrasive nature of the board remains the primary driver of wear.