Liquitex - Acrylic Fluid Medium - Ultra Matte Medium - 16 oz - Additives allow the artist to adjust the working properties of acrylic paint. They can be used to increase the flow, the opacity, or the thickness, and more. While they do contain acrylic polymer for compatibility, they do not contain sufficient acrylic resin to act as a binder within the paint. Liquitex Flow Aid Medium Fluid Additive breaks water tension for improved flow, absorbency and blending of any water based paint, ink or dye and minimizes brush strokes. Use with liquitex Soft Body color to create very fluid washes without hard edges. Great for staining effects on raw canvas. Should not add more than 25% as there is no binder and it can weaken the stability of the paint film when too much is added.