Golden Wetting Aid is a concentrated acrylic additive used to increase the slickness and flow of the paint. It allows you to achieve rich stains on porous surfaces and other watercolor-like effects with acrylics. Use by pre-diluting Wetting Aid with water before mixing with acrylic paint. The mixture can be applied directly to the surface before painting or mixed with acrylic paint before applying to the surface.
Wetting Aid, Golden's improved version of their Wetting Agent, is a surfactant. A surfactant is a concentrated surface-active liquid that reduces surface tension, thus improving wetting and increasing the flow of acrylic waterborne paints. This medium is very useful for staining techniques, as it dramatically reduces the surface tension between the stain 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.