FURNISH OPTIMIZATION FOR PAPERBOARD

Abstract

Paperboard is manufactured by a single piy or multi-ply layer in there furnishes. Raw material use in symmetrical paperboard are bleached hardwood, bleached softwood, broke, deinked pulp, chemical pulp, old newsprint, mixed waste, old corrugated container etc. Multi-ply paperboard is made up of liner plies i.e. top and bottom layer, and filler plies i.e. middle layer. The basic requirements for the paperboard are mechanical strength and stiffness. They may be stacked on top of each other, so that sufficient compression strength is required. Bending stiffness is affected mainly by thickness of paperboard and modulus of elasticity given by the raw material in it. The optimum structure is that the middle ply is very bulky and the top and back plies have high modulus of elasticity. The lower the basis weight that can be achieved by at given stiffness, better the yield is.