Immutable conducting films, which adhere to any clean solid have been formed from synthetic resin solutions holding finely ground carbon in suspension. Values of surface resistivity for uniformly thin films were secured in the range 15 to 106ohms referred to unit area of surface. When the thickness is held constant, the resistivity depends mainly upon the proportion of binder present and the kind of carbon used. The experimental error in repeating values of resistance with a given suspension is about plusmn;20 percent. The dependence of resistance upon resin content of the film appears to be in accord with the views of Frenkel concerning gap contacts and in definite disagreement with the classical Maxwell theory of composite conductors. The behavior of various types of carbon, when used in the films, can be predicted qualitatively from electrical measurements made upon powdered samples subjected to high pressure. Absorption of moisture by a film leads to a rise in resistance.
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