Sennelier has selected high quality pigments, from the most demanding chemical laboratories, in order to maximize purity and clarity of tone for this acrylic line. With 26 shades, Sennelier offers a broad palette, including four interference colors and six iridescent tones. Sennelier has also included the colors that made its line of extra-fine oils famous; the color chart includes the traditional ultramarines, earths, and ochres. It includes, among others, tones made from cadmium and cobalt based pigments. These colors offer a creamy and rich texture, revealing desired brush or knife marks; high pigment content (primarily single pigments), selected to provide optimal stability over time. Sennelier extra-fine acrylic color offers the possibility of working with layers or wash drawings, in combination with other techniques such as pastels, charcoal, or ink. It can be used outdoors and in the studio. It provides very good adhesion on many non-oily surfaces: paper, canvases, cardboard canvases, wood, fabric, cement, plaster, some plastics and metals. The color has little odor and dries rapidly to create a permanent, insoluble, non-cracking, non-yellowing, water resistant film. Colors meet the ASTM D5098 standard, testifying to their lightfastness.