Jo Sonja's Artists' Colours'are flow formula acrylics offering the opacity of color and the beautiful, velvet matte finish associated with traditional gouache plus superb handling and brushing characteristics. Unlike gouache, they are water-resistant and will not chip or crack when cured. Made from the finest quality pure pigments, the colors will remain vibrant and true for generations. They are safe, water based and clean up easily with soap and water. Suitable for all surfaces including paper, papier mach', card, canvas, wood, fabric, tin, terracotta, glass and tile.