Oil
Oil on Cotton (Repellix Coated)
Top view, fabric visible beneath
Tilted side view
Side View
Oil on uncoated cotton
Repellix Coated Copper Comb PCB
Oil (Left) and Water (Right)
Oil on Copper
Oil on Resin Substrate
Water on Resin Substrate
Oil is generally more difficult to repel than water, and produces lower contact angles on goniometer readings. IST applied olive oil to cotton fabric and PCB materials (uncoated or coated with Repellix) to examine the repellency.
While oil is not as superhydrophobic as water, we were able to create oleophobic conditions with Repellix. Uncoated samples simply smeared within seconds of contact with oil.