Golden Acrylic Flow Release is a surfactant. A surfactant is a concentrated surface-active liquid which reduces surface tension, thus improving wetting and increasing the flow of acrylic waterborne paints.
A surfactant is used several ways in acrylic paint making. Surfactants are used to "wet out" pigments to ease their introduction into an acrylic resin, medium or gel. They can also be added to thinner paint mixtures, such as stains, to help reduce surface tension.
Acrylic Flow Release is very useful for staining techniques, as it dramatically reduces the surface tension between the stain (paint/water) and the support. Certain supports, especially raw canvas, are inherently water repelling in nature and require the use of such a surface-active agent to allow the stain to wet and penetrate into the support.