Used to reserve areas which are to remain unpainted, especially in airbrush techniques, but also with watercolors and temperas, Designers Liquid Colors, Liquid Acrylic and India Ink. Liquid Mask forms a protective film on the area which the artist does not want to paint. Once the work is dry, liquid mask is rubbed off with an eraser or piece of cloth, revealing unpainted area. If the masking fluid is used with Model Color, paint should be diluted with water, since the undiluted acrylic may form a uniform coat with Liquid Mask, and will lift off together with the product when the work is done.