Method for the manufacture of polyethylene-based, soft nonwoven fabric

Abstract

The present invention concerns a method for the manufacture of nonwoven fabric the fibers of which have polyethylene on at least part of their surface, where the fibers are thermally bonded and the non-woven fabric exhibits an abrasion of less than 0.5 mg/cm 2 , in particular of less than 0.4 mg/cm 2 , and an embossed area fraction of less than 35%, in particular of less than 28%. Furthermore a device is made available for the manufacture of a non-woven fabric, using a polyethylene-containing polymer, with a take-down system underneath a spinning plate that causes the take-down of the polyethylene, where the spinning plate has an L/D ratio of between 4 and 9.

1 . A method for the manufacture of a nonwoven fabric, the fibers of which at least in part have polyethylene on their surface, where after take-down from a spinning plate at a speed of at least 650 m/min, the fibers are further processed, where the polymer in the extruder is heating to between 200° C. and 250° C. and passes at this temperature through the spinning plate heated to a temperature between 200° C. and 250° C., where the polymer is divided into individual polymer threads through at least 4500 holes/m, where the polymer threads each pass through the spinning plate on a passageway which is at least four times as long as the diameter of the polymer threads. 
     
     
         2 . A method according to  claim 1 , wherein the passageway is at least four times as long as the diameter of a boring of the passageway. 
     
     
         3 . A method according to  claim 1 , wherein the polymer threads are stretched with a take-down speed of between 3000 m/min and 4500 m/min. 
     
     
         4 . A method according to  claim 1  wherein the polyethylene is mixed with another polymer as dry blend or compound before going into the extruder. 
     
     
         5 . A method according to  claim 1  wherein the polymer threads are deposited on a screen belt and are then thermally bonded by means of a calendar, the rollers of which are heated to a different extent. 
     
     
         6 . A method according to  claim 1  wherein the polymer threads are thermally bonded at a surface temperature range of 112-140° C., with a consolidating area fraction below 35%.