Water-retentive cellulose fiber, method of manufacturing the same, and water-retentive sheet comprising cellulose fiber of high water retentivity

摘要

A powdered super absorbent polymer (SAP) has heretofore been used as a water retentive material for sanitary products, such as sanitary napkin, disposable diaper and incontinence pad. This water retentive material is used by being held between two paper sheets but the powdered SAP comes off easily from absorbent 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 wearer of the sanitary product. Consequently, water absorbency decreases with poor shape stability. Moreover, since the SAP in a water-absorbed gel state is sticky, the wearer feels unpleasant. P P According to the present invention, therefore, a cellulose fiber, such as a viscose rayon fiber containing uniformly a non- cellulose based material of high water absorbency such as polyacrylate salt is manufactured. A fiber web and nonwoven fabric produced of this fiber is used as water retentive materials in an absorbent member. This fiber has high absorbency and moreover high water retentivity such that water absorbed into the fiber is hardly released from the fiber. Accordingly, an absorbent 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 absorbency and high water retentivity. Therefore, when this water-retentive sheet is used, a thin absorbent member of high absorbency can be provided.