Method for the production of nonwoven webs, the cohesion of which is obtained by means of fluid jets

Abstract

The invention concerns a method for producing a nonwoven web formed at least partly with hydrophilic elementary fibers which consist in: producing by carding a textile layer ( 10 ) which is then compressed and moistened; subjecting it to a bonding treatment using water jets acting at least against one of its surfaces; and transferring said bonded layer to a unit ( 32, 33 ) to be dewatered and dried. Said method is characterised in that, after the bonding treatment ( 20 ) with water jets and before drying and delivery, the pre-bonded and moistened layer is transferred to a supplementary unit ( 28 ) to be treated by the action of one or several series of water jets, said unit comprising a mobile suction surface in the form of a drum covered with an open-work structure ( 30 ) consisting of a wire-mesh fabric, comprising successive raised and recessed zones.

1 . A method for producing a nonwoven consisting at least partially of hydrophilic elementary fibers, which involves continuously: 
 producing a fibrous web ( 10 ) by carding or another conventional technique;    compressing and moistening said web;    subjecting the moistened and compressed web to a bonding treatment by means of water jets acting at least against one of its faces, the web being supported by a rotary drum comprising randomly distributed microperforations, a partial vacuum being applied to the interior of said drum;    transferring said bonded web to an assembly ( 32 ,  33 ) making it possible to drain and dry it before it is received, in particular in the form of a wound package,    characterized in that, after bonding treatment ( 20 ) by means of water jets and before drying and reception, the prebonded and moistened web is transferred to an additional assembly ( 28 ) for treatment by the action of one or more series of water jets, said assembly comprising a movable suction surface taking the form of a drum covered with a removable sleeve defining an open-work structure ( 30 ) consisting of a woven bronze-wire cloth and shaped to have a succession of raised and recessed zones, the raised zones being obtained by embossing, the ratio of emptiness in relation to the surface being between 10 and 50%, and the overall height between the bottom of the recessed parts and the upper part of the raised zones being between 0.5 and 2 mm.    
     
     
         2 . A nonwoven web obtained by bonding by means of jets of water under pressure from elementary viscose fibers having a succession of raised and recessed designs.  
     
     
         3 . A nonwoven web obtained by bonding by means of jets of water under pressure from elementary fibers comprising a mixture of absorbent artificial fibers and of synthetic fibers having a succession of raised and recessed designs.  
     
     
         4 . A nonwoven web obtained by bonding by means of jets of water under pressure from elementary chemical, artificial and/or synthetic fibers taken alone or in a mixture and associated with natural fibers such as wood fibers, having a succession of raised and recessed designs.  
     
     
         5 . The use of nonwoven webs as claimed in one of  claims 2  to  4 , as wiping material or support for wet wipes.