Griffin Alkyd Fast Drying Oil Colour can be either mixed with regular oil colours or used underneath them. It is particularly popular for making a quick underpainting, followed by Winsor & Newton Artists’ Oil Colour or Winton Oil Colour for overpainting.
However, as the alkyd film is slightly less flexible and faster drying than traditional oils, applying Griffin Alkyd films over oil colour or Oilbar layers is not recommended.
Please note that Oilbar has now been discontinued.