MM31 Open Medium is formulated to be mixed with either Matisse Structure or Matisse Flow acrylic colours to assist in prolonging drying time while maintaining the consistency of the paint. When mixed with Matisse Structure, they will retain their impasto quality, while Matisse Flow Acrylics will keep their smooth flowing feel with added body but not viscosity.Optimal for painting outdoors or in particularly hot weather, MM31 Open Medium allows the paint to be blended on the painting surface for longer. Artists will be delighted with the way this medium makes their paint handle, so smooth and buttery. Be surprised by the glowing satin finish that this medium imparts to the paints.Available in 250ml and 1 Litre sizes.Mixing RatiosAs little as 10% MM31 Open Medium to the paint, will lengthen the working time, allowing satisfying, smooth blends. By choosing to use smaller amounts of medium, the blending time is increased, but drying time is not drastically increased. However, a larger amount of Open Medium will dramatically increase the working time of the paint. The maximum retardation of drying time is reached with an equal mixture of paint to medium. Beyond this point, any further additions of MM31 Open Medium will result in minimal increases of drying time but may reduce waterfastness of the dried paint. However larger proportions (more medium than paint) will give transparency and will aid effective layering.As well as allowing more time to blend on the surface, paint mixed with MM31 Open Medium will stay fresh on the palette for several hours, depending both on the weather conditions and the quantity of MM31 Open Medium used. Easy to use, MM31 Open Medium will allow the reworking of areas of a painting in a way not previously possible.The gel-like consistency of MM31 Open Medium allows it to remain in place on the palette, therefore it is suitable to be brush-mixed while painting, as well as to be pre-mixed on the palette.