Neutral liquid frisket acts as a drawing gum for masking specific areas that should remain white on watercolour paper, smooth drawing cardboard, photographs and films. Colourless after drying, it is dilutable with water, but dries very quickly into a rubbery-type transparent film that does not dissolve in water. Once dry, masked picture areas can be painted over using watercolours, gouache colours or AERO COLOR® Professional. Tips: Apply with writing pen, cotton bud or wooden stick. Drying process takes between a few minutes to more than an hour depending on the thickness of the coat applied. Very soft textured papers like rag paper or torchon paper are not suitable for masking techniques.