Abstract
Absorbency in several different types of baby diapers and sanitary napkins was studied by considering the structural factors such as pore size and distribution, web thickness, basis weight, and the application method of SAP(super absorbent polymer). The structural factors considered significantly affected the absorbency capacity and rate. The pore size which plays a key role in determining absorbency could be derived as a function of the constituent fiber diameter, the web thickness and weight. The decrease in pore size led to an increase in the capillary pressure and thus increased th initial absorbency rate. Absorbency capacity was proportional to the amount of SAP while the increase in SAP amount gave a decrease in absorbency rate due to the gel blocking phenomena. Semi-empirical models modified from the Washburn's equation were introduced to provide a criterion in the analysis of the absorbency of diapers.
