3.2. Water and oil repellency
Water repellency was measured by means of the AATCC test method 193-2005 [20]. This test method evaluates the fabric's resistance to wetting by a selected series of 8 water/alcohol solutions of different surface tensions. Drops of standard test liquids are placed on the fabric surface and observed for wetting and wicking. The aqueous repellency grade is the number corresponding to highest numbered test liquid that does not wet the fabric surface within 30 s; when the drop does not wet the sample but shows partial darkening, 0.5 is added to the test liquid number.