Water-and oil-repellent coatings by plasma treatment

The morphology of the coating and the deposition rate are controlled by the reaction mechanism and reaction rate. Readily polymerizing systems 

The structures achieved with plasma chemical deposited FC layers are characterized by a nanometer-scaled thickness and relatively high degree of cross-linking. Plasma polymerized layers with FCs in DBD show surface energies of 11 mN/m on polymeric films. These values are significantly lower than the typical value of PTFE with 18 mN/m.  

In encapsulated continuously working plasma units (Fig. 15.7), oil repellency grades of 5-6 (according to AATCC 118-1992) have been obtained on PET-Monofil fabric at a process speed of 0.5 m/min (Fig. 15.8). Better oil-repellent properties than those of PTFE were obtained, but the properties of water-based FC finishing have not been completely achieved until now. Oil repellencies on treated fabrics increase with decreasing process speeds, increasing fluorocarbon layer thicknesses. The thickness of plasma polymerized 

FC layers on fibers of up to 14 nm was extrapolated from IR measurements on plasma-treated Si-wafers (Fig. 15.9). Deposition rates of up to Inm/s on fibers were achieved. 

The use of aerosols in plasma technology increases the application spectrum of suitable chemicals enormously. With the help of aerosols in atmospheric pressure liquid chemicals, solutions and, in a limited way, dispersions can be used in plasma for surface modification. The potential of combinations from aerosols and spraying application in the DBD for the surface treatment of textiles is in the first development stage. Examples for current and future 

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