What alternatives can I use instead of liquin?

Liquin was formulated by Winsor and Newton for use with their Alkyd Fast Drying Oil Paint but it has become very popular with artists who use oil paint regularly. The Liquin is designed to aid in the speed at which the paint drys and is excellent for use in glazing. After my acrylic block-in is dry, I very often use Liquin as a glaze over the block-in and then add my details on top of that depending on the subject I am painting. Any medium that is suitable for oil paint can be used for this technique. If linseed oil is used it will make the paint film dry slower.