Method for producing a structured microfilament nonwoven

Abstract

In an embodiment, the present invention provides a method for producing a structured microfilament non-woven, including: forming a non-woven by spinning microfilaments and/or composite filaments that can be split into microfilaments to form at least one fiber layer, stretching the at least one fiber layer, and laying the at least one fiber layer; thermally pre-bonding the non-woven; treating the thermally pre-bonded non-woven using a pressurized medium in order to break the thermal pre-bonding at least in part; and further applying a pressurized medium to the non-woven while the non-woven is resting on a structure-producing surface, so as to obtain a structured microfilament non-woven.

1 . A method for producing a structured microfilament non-woven, comprising:
 forming a non-woven by spinning microfilaments and/or composite filaments that can be split into microfilaments to form at least one fiber layer, stretching the at least one fiber layer, and laying the at least one fiber layer;   thermally pre-bonding the non-woven;   treating the thermally pre-bonded non-woven using a pressurized medium in order to break the thermal pre-bonding at least in part; and   further applying a pressurized medium to the non-woven while the non-woven is resting on a structure-producing surface, so as to obtain a structured microfilament non-woven.   
     
     
         2 . The method according to  claim 1 , wherein the non-woven is not needled or adhesively bonded for the purpose of pre-bonding. 
     
     
         3 . The method according to  claim 1 , wherein the thermal pre-bonding is carried out using a heated calendar. 
     
     
         4 . The method according to  claim 1 , wherein the treatment using a pressurized medium for breaking the thermal pre-bonding, and the treatment using a pressurized medium for structuring the non-woven are carried out in the same apparatus. 
     
     
         5 . The method according to  claim 1 , wherein the treatments using a pressurized medium for breaking the thermal pre-bonding and/or for structuring the non-woven split composite filaments into microfilaments at least in part and intertwine said filaments with one another. 
     
     
         6 . A structured microfilament non-woven produced using the method according to  claim 1 . 
     
     
         7 . The structured microfilament non-woven according to  claim 6 , wherein a structuring pattern of the structured microfilament non-woven can be identified visually and/or haptically after 30 domestic washing cycles at 90° C. in accordance with DIN EN ISO 6330. 
     
     
         8 . A structured microfilament non-woven according to  claim 6 , wherein a mass per unit area of the non-woven is less than 50 g/m 2 . 
     
     
         9 . The structured microfilament non-woven according to  claim 6 , wherein the microfilaments contain thermoplastic polymers in a proportion of at least 20 wt. % based on the total weight of the non-woven. 
     
     
         10 . The structured microfilament non-woven according to  claim 6 , wherein a proportion of microfilaments is at least 70 wt. % based on a total weight of the non-woven. 
     
     
         11 . The structured microfilament non-woven according to  claim 6 , wherein a proportion of composite filaments in the microfilament non-woven that are split at least in part into microfilaments and intertwined is over 70 wt. %. 
     
     
         12 . The structured microfilament non-woven according to  claim 6 , wherein a degree of splitting of the composite filaments is over 80%. 
     
     
         13 . The structured microfilament non-woven according to  claim 6 , wherein the composite filaments and/or the microfilaments contain at least two incompatible thermoplastic polymers selected from polyester, preferably polyethylene terephthalate, polylactic acid and/or polybutylene terephthalate, on the one hand, and polyamide, preferably polyamide 6, polyamide 66 or polyamide 46, on the other hand. 
     
     
         14 . The structured microfilament non-woven according to  claim 6 , wherein the composite filaments contain at least one polymer pair consisting of at least one polyester and at least one polyamide. 
     
     
         15 . Use of the structured microfilament non-woven according to  claim 6  as a cleaning cloth, towel, cloth for sanitation purposes, bed linen, upholstery fabric, or lining material. 
     
     
         16 . The structured microfilament non-woven according to  claim 10 , wherein the proportion of microfilaments is from 70 wt. % to 100 wt. % based on the total weight of the non-woven. 
     
     
         17 . The structured microfilament non-woven according to  claim 16 , wherein the proportion of microfilaments is approximately 100 wt. % based on the total weight of the non-woven. 
     
     
         18 . The structured microfilament non-woven according to  claim 12 , wherein the degree of splitting of the composite filaments is over 95%. 
     
     
         19 . The structured microfilament non-woven according to  claim 13 , wherein the at least one polyester comprises polyethylene terephthalate, polylactic acid, and/or polybutylene terephthalate. 
     
     
         20 . The structured microfilament non-woven according to  claim 13 , wherein the at least one polyamide comprises polyamide 6, polyamide 66, or polyamide 46.