PRACTICAL ASPECT OF ALKALINE SIZING: ALKYL KETENE DIMER(A.K.D) IN MILL FURNISHES

Abstract

Papermaking fibers have a strong natural tendency to interact with water. This property is important to the development of strong inter fiber hydrogen bonds during papermaking and is also the reason that paper loses its strength when saturated with water. This behavior is an advantage for certain absorbent paper grades such as toweling and tissue. Corrugating medium must also be highly absorbent to convert properly in the corrugating process. Such properties are not common for most paper grades, however. It is more typical for papers to interact only moderately with water during use. Table- 1 lists some common examples. Table 1 Paper end uses and converting requirements needing liquid penetration resistance ❖ Liquid packaging ❖ Offset printing ❖ Wet/frozen foods packaging ❖ Gluability ❖ Water-based ink holdout •'• Off-machine coating Liquid penetration resistance is also important to many papermaking processes where paper is brought into contact with aqueous solutions, such as size pressing, coating, and calendar water box applications. Finally, many papers (e.g. office papers, cereal boxes, cosmetic boxes, grocery bags must be able to resist accidental wetting during use..................