The next quantum leap in papermaking will be the introduction of stratified forming in order to reduce energy consumption, improve product properties and possibly develop completely new products. Contrary to multiply forming, stratified forming produces a layered structure with one single headbox. By using a single headbox, sheet stratification can be applied even to low-grammage products, e.g. newsprint.

 

Stratified forming makes it possible to produce printing paper grades with different furnishes in the different layers. Another interesting possibility would be to use wood containing pulp in the middle layer sandwiched between two bleached surface layers, obtaining the same product properties that can be obtained with 100% virgin kraft pulp today.

 

For multiply grades, such as liner or board, stratified forming applied on the top ply means added design freedom since different functionalities, e.g. printing quality, mechanical properties and hydrophobicity, could be introduced of the top layer. Products with these characteristics would imply a significant environmental benefit while providing improved competitiveness.