Nonwoven cellulose fiber fabric with increased oil absorbing capability

Abstract

It is described a nonwoven cellulose fiber fabric directly manufactured from a lyocell spinning solution. The fabric comprises a network of substantially endless fibers, wherein the fabric exhibits an oil absorbing capability of at least 1900 mass percent. It is further described a method and a device for manufacturing such a fabric, a product or composite comprising such a fabric, and various use applications for such a fabric.

1 . A nonwoven cellulose fiber fabric, in particular directly manufactured from a lyocell spinning solution, the fabric comprising
 a network of substantially endless fibers, wherein   
       the fabric exhibits an oil absorbing capability of at least 1900 mass percent. 
     
     
         2 . The fabric as set forth in  claim 1 , wherein
 the fabric comprises a mass per unit area which is smaller than 150 gram per square meter, in particular smaller than 100 gram per square meter, further in particular smaller than 50 gram per square meter and even more in particular smaller than 20 gram per square meter.   
     
     
         3 . The fabric as set forth in  claim 1 , wherein
 the network exhibits a merging factor of the fibers, which is in a range between 0.1% and 100%, in particular in a range between 0.5% and 10%.   
     
     
         4 . The fabric as set forth in  claim 1 , wherein
 at least some individual fibers are twisted with each other and/or   at least one other fiber structure is twisted with another fiber structure.   
     
     
         5 . The fabric as set forth in  claim 1 , wherein
 the fabric exhibits an oil absorbing capability of at least 2100 mass percent, in particular of at least 2300 mass percent, and more in particular of at least 2500 mass percent.   
     
     
         6 . The fabric as set forth in the  claim 1 , wherein
 different ones of the fibers are located at least partially in different distinguishable layers.   
     
     
         7 . The fabric as set forth in  claim 6 , comprising at least one of the following features:
 fibers of different layers are integrally connected at at least one inter layer merging position between the layers;   different ones of the fibers being located at least partially in different layers differ concerning fiber diameter, in particular differ concerning an averaged fiber diameter;   fibers of different layers have the same fiber diameter, in particular have substantially the same averaged fiber diameter; or   fibers networks of different layers provide different functionality, wherein the different functionality in particular comprises at least one of the group consisting of different wicking, different anisotropic behavior, different liquid absorbing capability, different cleanability, different optical properties, different roughness, different smoothness, and different mechanical properties.   
     
     
         8 . The fabric as set forth in  claim 6 , wherein
 the fiber networks in different layers have different merging factors.   
     
     
         9 . The fabric as set forth in  claim 1 , wherein the fibers have a copper content of less than 5 ppm and/or have a nickel content of less than 2 ppm. 
     
     
         10 . A method of manufacturing nonwoven cellulose fiber fabric, in particular a fabric as set forth in  claim 1 , directly from a lyocell spinning solution, the method comprising
 extruding the lyocell spinning solution through a jet with orifices supported by a gas flow into a coagulation fluid atmosphere to thereby form substantially endless fibers;   collecting the fibers on a fiber support unit to thereby form the fabric; and   adjusting process parameters of the manufacturing process so that   the fabric exhibits an oil absorbing capability of at least 1900 mass percent.   
     
     
         11 . The method as set forth in  claim 10 , wherein
 adjusting the process parameters comprises at least one of the following features:   forming at least part of the merging position after the lyocell spinning solution has left the orifices and before the lyocell spinning solution has reached the fiber support unit by triggering an interaction between lyocell spinning solution extruded through different ones of the orifices;   forming at least a part of the merging positions after the lyocell spinning solution has reached the fiber support unit by triggering coagulation of at least part of the fibers when laying on the fiber support unit; or   serially arranging multiple jets with orifices along a movable fiber support unit, depositing a first layer of fibers on the fiber support unit, and depositing a second layer of fibers on the first layer before coagulation of at least part of the fibers at an interface between the layers has been completed.   
     
     
         12 . The method as set forth in  claim 10 , further comprising
 further processing the fibers and/or the fabric in situ after collection on the fiber support unit, in particular by at least one of the group consisting of hydro-entanglement, needle punching, impregnation, steam treatment with a pressurized steam, and calendering.   
     
     
         13 . A device for manufacturing nonwoven cellulose fiber fabric directly from a lyocell spinning solution, in particular for manufacturing a fabric as set forth in  claim 1 , the device comprising
 a jet with orifices configured for extruding the lyocell spinning solution supported by a gas flow;   a coagulation unit configured for providing a coagulation fluid atmosphere for the extruded lyocell spinning solution to thereby form substantially endless fibers;   a fiber support unit configured for collecting the fibers to thereby form the fabric; and   a control unit configured for adjusting process parameters so that the fabric exhibits an oil absorbing capability of at least 1900 mass percent.   
     
     
         14 . A method of using a nonwoven cellulose fiber fabric according to  claim 1  for at least one of the group consisting of a dryer sheet, a facial mask, a hygiene product, a wipe, a filter, a medical application product, a geotextile, agrotextile, clothing, a product for building technology, an automotive product, a furnishing, an industrial product, a product related to leisure, beauty, sports or travel, and a product related to school or office. 
     
     
         15 . A product or composite comprising a nonwoven cellulose fiber fabric as set forth in  claim 1 .