MODULATED PLASMA GLOW DISCHARGE TREATMENTS FOR MAKING SUPERHYDROPHOBIC SUBSTRATES

摘要

The present invention deals with a method of treating polymeric or non polymeric articles for making their surface superhydrophobic, i.e. characterized by static water contact angle (WCA) values higher than about 120~, preferably higher than 130~, more preferably higher than 150~. The method consists of a modulated glow discharge plasma treatment (1) performed with a fluorocarbon gas or vapor compound fed in a properly configured react or vessel where the substrates are positioned. The plasma process deposits a continuous, fluorocarbon thin film with superhydrophobic surface characteristics, tightly bound to the substrate. The substrates of interest for the present invention may include a wide range of materials in form of webs, tapes, films, powders, granules, woven and non-woven layers; substrate s can be porous or non-porous, molded or shaped, rigid or flexible, made of polymers, textiles, papers, cellulose derivatives, biodegradable materials, metals, ceramics, semiconductors, and other inorganic or organic materials. Preferably, the substrate is formed into a desired shape or configuration, depending on its intended use, before being subjected to the treatment objec t of this invention. When organic synthetic resins are chosen, such substrate materials could be fabricated from polyethylene, polyacrylics, polypropylene , polyvinyl chloride, polyamides, polystyrene, polyurethanes, polyfluorocarbon s, polyesters, silicon rubber, hydrocarbon rubbers, polycarbonates and other synthetic polymers. A particularly preferred polymeric substrate is polyethylene or polypropylene.