Sizing Performance of the Cationic Rosin Emulsion Size at Near Neutral Conditions

Abstract

Recently, for the internal sizing, the rosin emulsion sizes are often used. There are two types of rosin emulsion size corresponded to the acidic conditions and the higher pH conditions. For the latter, the rosin ester-type emulsion sizes are well known. The sizing performance of this type is not satisfactory at near neutral conditions, because of the dependence upon the amount of alum used. The high performance rosin emulsion size, more reasonable price and easier to use than AKD and ASA, is required, under neutral papermaking is advanced in order to improve the quality of paper and reduce the cost. We investigated a new size in terms of the components of resin and the ionicity of polymer surfactant, and found that the size, formed by dispersing the fortified rosin and petroleum resin mixture with a cationic surfactant, is excellent in comparison with rosin-ester size.