Contact Angle θ—
Wetting State—
Work of Adhesion WA—
Spreading Coeff. S—
Young's Equation:
γSV = γSL + γLV·cos θ
Young-Dupré adhesion:
WA = γLV(1 + cos θ)
Spreading coefficient:
S = γSV - γSL - γLV
S≥0: complete wetting; S<0: partial
γSV = γSL + γLV·cos θ
Young-Dupré adhesion:
WA = γLV(1 + cos θ)
Spreading coefficient:
S = γSV - γSL - γLV
S≥0: complete wetting; S<0: partial
The contact angle balances three surface tensions at the triple contact line. θ<90°: hydrophilic. θ>90°: hydrophobic. θ>150°: superhydrophobic (Lotus effect).