Relationship of the Contact Angle to Interfacial Energies

Abstract

The commonly used relation between the contact angle and the specific free energies of three surfaces meeting at a line is correct, although it has been criticized in recent years. A rigorous derivation of the kind applicable to systems which can be analytically described is presented in detail. The completely general derivation of Gibbs is also reviewed. The kinds of errors in the derivations found in many texts are discussed.