Grooved Counterpart
Precision channels on the press platen receive the paperboard when the steel creasing rule descends to form a fold. The component known as the female creasing matrix provides the opposing groove that allows the board to stretch and delaminate internally without rupture. This piece is applied to the counter-die plate of the press during setup.
It is not used for direct-cut operations, where only a sharp blade and a flat cutting plate are required. Choosing the correct matrix thickness is essential for processing high-density board.
Crease Formation
Clean folds require a controlled deformation of the board’s internal layers. As the rule descends, the female creasing matrix supports the outer shoulders of the crease while the center is pushed down. This action creates a bead on the reverse side of the board.
The bead allows the board to fold with low resistance.
Material Alignment
Accurate positioning of the matrix on the cutting plate prevents asymmetric creases. When using a self-adhesive female creasing matrix, the converter attaches the matrix to the creasing rule first, then transfers it to the platen. This procedure ensures perfect alignment with the rule.
This alignment prevents the board from cracking during the folding step.
