Foaming agent Foaming agent A foaming agent is a material that facilitates formation of foam such as a surfactant or a blowing agent. A surfactant, when present in small amounts, reduces surface tension of a liquid (reduces the work needed to create the foam) or increases its colloidal stability by inhibiting coalescence of bubbles. A blowing agent is a gas that forms the gaseous part of the foam. Sodium laureth sulfate, or sodium lauryl ether sulfate (SLES), is a detergent and surfactant found in many personal care products (soaps, shampoos, toothpastes, etc.). It is an inexpensive and effective foamer. Sodium lauryl sulfate
Meniscus (liquid) in glass or other wettable containers. Conversely, a convex meniscus occurs when the particles in the liquid have a stronger attraction to each other than to the material of the container. Convex menisci occur, for example, between mercury and glass in barometers and thermometers. The formation of menisci is commonly used in surface science to measure contact angles and surface tension. In a contact angle measurement, the shape of the menisci is measured with a balance or optically with a digital camera. In a surface tension measurement, the measurement probe has a contact angle of zero and the surface tension