Advancing/receding contact angles tilting plate method

Figure 9.2 Determination of contact angle from the sliding drop on an inclined plate method. The advancing contact angle, 9 , is the measured angle at the downhill edge of the drop, the receding contact angle, 0r is measured at the uphill edge, and 0, is the tilt angle.

FIG. 24 Principle of the method for the measurement of contact angle using tilted plate based on geometrical instability of two-dimensional meniscus (a) receding contact angle (b) advancing contact angle. 

FIG. 34 Comparison of contact angles measured by the proposed method using tilted plate with those by a commercially available contact angle meter (a) advancing contact angle (b) receding contact angle. 

Advancing and receding contact angle should be determined by the drop expansion/ contraction technique. The tilting plate method has significant shortfall particularly with high hysteresis samples and should be avoided if possible. 

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