| CPC B32B 27/08 (2013.01) [B32B 3/30 (2013.01); B32B 5/147 (2013.01); B32B 7/12 (2013.01); B32B 27/18 (2013.01); B32B 27/32 (2013.01); B32B 27/36 (2013.01); B32B 27/365 (2013.01); B32B 2250/242 (2013.01); B32B 2270/00 (2013.01); B32B 2307/412 (2013.01); B32B 2307/73 (2013.01); B32B 2307/732 (2013.01); B32B 2457/12 (2013.01); B32B 2605/006 (2013.01)] | 19 Claims | 

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               1. A multi-layer polypropylene film comprising: 
              a base layer of a polypropylene (PP); 
                optionally, a tie layer comprising a blend of polypropylene and a sacrificial engineering thermoplastic selected from polybutylene terephthalate (PBT) or polycarbonate (PC); and 
                a top layer comprising a film having a structured surface with a water contact angle of greater than 104.5°; 
              wherein the top layer comprises a blend 20 to 40 wt % of the polypropylene and 60 to 80 wt % of said sacrificial engineering thermoplastic and in which the sacrificial engineering thermoplastic has been selectively etched in order to create the said structured surface. 
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