Comparison between uncreped and creped handsheets on tissue paper properties using a creping simulator unit

A comparison between uncreped and creped handsheets was performed to study the effect of fiber morphology and creping process on fiber web structure and tissue properties. Four wood and non-wood pulps refined at different levels were used to manufacture uncreped and creped handsheets using a creping simulator. A characterization of the fiber web structure using scanning electron microscopy (SEM) and evaluation of tissue properties (e.g. tensile strength, water absorbency, softness) was performed on the uncreped and creped handsheets. The results obtained with the creping simulator were compared with commercial products to evaluate the significance of the creping simulator results. The SEM images of the fiber web structure showed that the creping process promoted buckling and distortion of fibers, delamination of surface fiber layer, development of free fiber ends and creation of crepe folds, which enhanced water absorbency and softness at the expense of reduced tensile strength. Short and thin fibers seemed to be more effectively creped than long and coarse fibers. Long and coarse fibers seemed to offer higher resistance to the compressive forces acting at the creping blade. A reasonable correlation between the performance of uncreped and creped handsheets made with different fibers was observed. The results indicate that the performance of uncreped handsheets can be used as a semi-quantitative indication of the performance of creped handsheets. The performance of the creped handsheets were similar to commercial products, which indicates that the creping simulator can be used as an alternative to study the creping process at laboratory scale.