J. Phys. III France
Volume 4, Numéro 4, April 1994
Page(s) 775 - 781
DOI: 10.1051/jp3:1994101
J. Phys. III France 4 (1994) 775-781

Critical radius of holes in liquid coating

Cécile Sykes, Claire Andrieu, Véronique Détappe and Sylvain Deniau

Laboratoire P.S.I. (associé au CNRS, URA 1379, et à l'Université Paris VI), Institut Curie, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, France

(Received 20 September 1993, revised and accepted 12 January 1994)

In this paper, we focus our interest on the stability of a thin liquid film deposited on a non-wetting surface. The film is metastable and dewets by nucleation and growth of dry patches. Dry patches grow only if the radius is greater than a critical value, $R_{\rm c}$. We measured $R_{\rm c}$ in the case of polythene terephtalate coated by glycerol or di-iodomethane as a function of e, the thickness of the film. The experimental results agree well with the predicted formula [5, 6] $R_{\rm c}=\frac{e}{\ell \sin \theta_{\rm e}}$, where $\theta_{\rm e}$, is the equilibrium contact angle and $\ell$ a logarithmic function of $R_{\rm c}$.

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