What do recyclers mean when they are referring to “corrugated case materials?”
Simply put – cardboard. A material known as corrugated board is made by a conversion process in which three or more layers of paper (or paperboard) are laminated together. The middle ply, which is called fluting, is corrugated during the process and the outer layers, called the liners, are glued to its peaks. This makes a liner-fluting-liner sandwich. The result is a light, strong material which has particular resistance to pressure applied to the vertical line of the corrugation. This gives the finished corrugated case a high stacking strength. It is these properties that have seen the corrugated case grow its market share, replacing traditional wooden and solid board boxes. Today corrugated case materials are the second largest of six sectors of the paper and board industry.