CONTAINERBOARD: HOW IT AFFECTS CONVERTIBILITY AND CORRUGATED BOARD.

This paper is concerned with some aspects of properties of both types of containerboard - linerboard and medium. The effect of the variables experienced commercially with these two materials is discussed in reference first to their converting efficiency and then toward their influence on corrugated board properties and ultimately on the properties of the corrugated shipping container. Roll quality is an important factor in convertibility. So, too, is the uniformity of moisture content of linerboard. Liner controls the mullen strength, hence rough handling performance. Compression strength, however, of both liner and medium may well be its most important property and today, this is a non-specification test, varying much more widely than the specified properties. Flat crush strength, contributed by the medium, is shown to be significant in determining whether the corrugated board can be processed adequately in the container plant.