WATER RETENTIVE CELLULOSE FIBER, METHOD OF MANUFACTURING THE SAME, AND WATER RETENTIVE SHEET COMPRISING CELLULOSE FIBER OF HIGH WATER RETENTIVITY

摘要

A powdered resin of high absorption power (SAP) has heretofore been used as a water retentive material for sanitary products, such as sanitary napkin, a paper diaper and an incontinence pad. This water retentive material is used by being held between two paper sheets but the powdered SAP comes off easily from an absorption member. Moreover, even when the SAP is in a dried powdered state or in a water-absorbed gel state, it is moved between a top sheet and a back sheet in accordance with the movement of a user of the sanitary product. Consequently, the water absorption power decreases, and the shape stability lowers. Moreover, since the SAP in a water-absorbed gel state is sticky, the user feels unpleasant. A cellulose fiber, such as a viscose rayon fiber containing uniformly a non-cellulose material of a high water absorption power, such as polyacrylate is manufactured, from which fiber a fiber web or a nonwoven cloth is manufactured, which is used as a water retentive material in an absorption member. This fiber has high water absorption power and moreover a high water retentivity, i.e. large absorbed water-holding power. Accordingly, an absorption member formed of a sheet made of this fiber has a stable shape both when it is in a dry state and when it is in a water-absorbed state, and, moreover, it has high water absorption power and a high water retentivity. Therefore, when this water retentive sheet is used, a thin absorption member of high water absorption power can be provided.