Among face masks containing a lotion and others, the nonwoven fabric containing a water absorbing fiber is used in order to make it good in liquid retention and a feeling of wearing. Such a non-woven fabric is produced mainly by thermal bonding processing. However, it is little entanglement of fibers and after wearing, fluff tends to be easily remained on the skin. As to reduction of the plush, the spinning lace processing is effective, however, it is difficult to be applied to the water absorbing and swelling water-absorbing fiber. The present invention provides a spun lace processed water-absorbent nonwoven fabric. A water-absorbing fiber precursor which is characterized in comprising 0.1 to 5.0 mmol/g of an H-type carboxyl group and less than 0.5 mmol/g of a salt-type carboxyl group, in which the total amount of the H-type carboxyl group and the amount of the salt-type carboxyl group is 0.5 mmol/g or more, the water absorption rate is 10 to 1000% by mass, and a water absorption rate is 500 to 50000% by mass when the neutralization degree of the carboxyl group is adjusted to 50%.在含有化妝水等之面膜中，為了使保液性或著用感成為良好而使用含有吸水性纖維之不織布。此種的不織布，雖然主要是藉由熱黏合加工所製造的，然而纖維之交絡少而在著用後容易在皮膚上殘留毛絨。毛絨之減少雖然紡紗蕾絲加工是有效的，然而吸水膨潤的吸水性纖維卻是難以適用。本發明乃提供一種經紡紗蕾絲加工過的吸水性不織布。一種吸水性纖維前驅物，其特徵在於：具有0.1～5.0 mmol/g之H型羧基及小於0.5 mmol/g之鹼基型羧基，前述H型羧基量與前述鹼基型羧基量之合計量為0.5 mmol/g以上，吸水率為10～1000質量%、且將羧基之中和度調整至50%時之吸水率為500～50000質量%。
