High moisture absorbent nonwoven fabric structure and production method thereof

Abstract

A high moisture absorbent nonwoven fabric structure comprising a moisture absorbing layer mainly consisting of high moisture absorbent fibers, and surface sheets sandwiching the moisture absorbing layer to constitute a three-layer structure. The high moisture absorbent fibers gel on the surfaces thereof by absorbing water and/or moisture to develop a self-bonding force. The high moisture absorbent nonwoven fabric has an absorptivity, after five hours at 20° C. and relative humidity of 65%, of at least 20 wt. %, at least one of the surface sheets has breathability, and the self-bonding force of high moisture absorbent fibers ensures bonding between fibers in the moisture absorbing layer and between the moisture absorbing layer and the surface sheets. The high moisture absorbent nonwoven fabric structure, which is high in hygroscopicity, applicable to a small space, and easily recyclable by heat treating nonwoven fabrics after moisture absorbed, can be used in a variety of fields such as desiccants and dehumidifying agents.

1 - 6 . (canceled)  
   
   
       7 . A drying agent having a nonwoven fabric structure, comprising: 
 a) the nonwoven fabric structure having three layers laminated in order, and including a first surface sheet, a moisture-absorbing layer consisting mainly of high moisture absorbent fibers, and a second surface sheet;    b) the fibers in the moisture-absorbing layer adhering to each other, and the moisture-absorbing layer and the surface sheets adhering to each other by a self-adhering activity of the high moisture absorbent fibers expressed by water absorption and/or moisture;    c) at least one of the surface sheets having air permeability;    d) the high moisture absorbent, nonwoven, fabric structure having a thickness not more than 1.5 mm;    e) the high moisture absorbent, nonwoven, fabric structure having a water content of 20 to 45 weight %; and    f) the high moisture absorbent, nonwoven, fabric structure averaging a moisture-absorbing rate of at least 20 weight % under an absolute dry condition at 20° C. and 65% relative humidity after 5 hours.    
   
   
       8 . The drying agent of  claim 7 , wherein the moisture-absorbing layer consists of high moisture absorbent fibers alone.  
   
   
       9 . The drying agent of  claim 7 , wherein the high moisture absorbent fibers are high moisture absorbent fibers of a crosslinked sodium acrylate.  
   
   
       10 . The drying agent of  claim 7 , wherein the fabric structure has an apparent density of 0.05 to 0.8 g/cm 3 .