Mediums
Although this type of paint may be thinned with water, artists may prefer to use specially prepared mediums for improved texture and control. These mediums improve flow (i.e., make the thinned paint less runny and more easily controlled), can slow or speed up drying time. Royal Talens also has produced a water mixable painting paste that acts as a thickener as well as transparetizer which will not change the consistency of the paint. There are many documented issues with accelerator products in this category causing cracking and damaging the archivability of the medium.
Winsor and Newton has created a special line of oils, mediums, varnishes, and thinners to complement their “Artisan” brand of water mixable oil colors. This line includes thinner, linseed oil, safflower oil, stand oil, painting medium, fast drying medium, and impasto medium, as well as gloss varnish, matt varnish, satin varnish, and varnish remover. All of these products are certified “AP Non-Toxic” by the Art & Creative Materials Institute (ACMI) in the United States.
Read more about this topic: Water Miscible Oil Paint