Interfacial tension - Kaimenchoryoku

This concept extends what has been thought about the surface tension of liquids to boundaries such as gas-liquid, liquid-liquid, liquid-solid, gas-solid, and solid-solid, and is equivalent to the work required to expand the interface by a unit area (interfacial energy dyn cm ^-2 ). Gas-liquid and liquid-liquid interfaces can be measured using methods similar to those used to measure the surface tension of liquids, but it is difficult to use similar methods at interfaces with solids, and it can instead be calculated indirectly from the contact angle observed when a drop of liquid is placed on a solid surface.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

液体の表面張力について考えられたことを気-液，液-液，液-固，気-固，固-固などの境界面に拡張した考え方で，界面を単位面積だけ広げるのに要する仕事(界面エネルギーdyn cm^－2)に相当する量である．気-液，液-液界面については液体の表面張力と同様の方法で測定ができるが，固体との界面では同様の方法を用いることは困難で，固体面に液滴をおいたときに観察される接触角から間接的に求められる．

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