On the formation and structure of multilayers

If the surface of a Langmuir trough be separated by a waxed thread into two compartments, a monolayer deposited on one side may be kept at constant pressure by placing a drop of a piston oil exerting a constant spreading pressure on the other side of the thread. On dipping and withdrawing a metal slide through the surface a monolayer may be deposited as shown by Langmuir (1934) and Miss Blodgett (1935) on the slide. Deposition may take place only on immersion of the slide, X deposition, on both downwards and ascending journey, Y deposition (Blodgett 1935), or only on withdrawal of the slide, Z deposition (Stenhagen 1938). By repeating the process multilayers may be formed. The present work was undertaken with a view to clarifying the process of deposition and the nature of “ built-up” multilayers and critically examining the hypothesis that they are superposed sheets of oriented molecules (Blodgett 1935).