On the influence of delamination on laminated paperboard creasing and folding

Laminated paperboard is used as a packaging material for a wide range of products.
During production of the packaging, the fold lines are first defined in a so-called creasing
(or scoring) operation in order to obtain uncracked folds. During creasing as well as
folding, cracking of the board is to be avoided. A mechanical model for a single fold
line has been proposed in a previous study (Beex & Peerlings 2009 Int. J. Solids Struct.
46, 4192–4207) to investigate the general mechanics of creasing and folding, as well as
which precise mechanisms trigger the breaking of the top layer. In the present study, we
employ this modelling to study the influence of delamination on creasing and folding. The
results reveal the separate role of the cohesive zone model and the friction model in the
description of delamination. They also show how the amount of delamination behaviour
should be controlled to obtain the desired high folding stiffness without breaking of the
top layer.