Drifted Bubbles from the Amphoteric Surface

DETACHMENT OF DRIFTED BUBBLES FROM THE AMPHOTERIC SURFACE 

The significance of sessile bubble development shown above could be rephrased as follows When a surface is immersed in water, the surface is wetted regardless of the contact angle of water or the wettability of the surface. When air is injected 

From examination of the dewetting process, the requirement for the wettable (by water) or hydrophilic surface could be defined that the contact angle of water should be below ti/2. By the same principle, a contact angle above n could be set as the requirement for the nonwettable or hydrophobic surface. The surface whose contact angle is between n and ti/2 could be viewed as the surface having amphoteric wettability or amphoteric hydrophilicity/hydrophobicity. 

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