Schmincke intermediate varnishes, retouching varnishes for painting in oil (EN)

Retouching varnishes /
intermediate varnishes

Intermediate varnishes or retouching varnishes are used solely for oil paintings. They normally contain less resin than final varnishes and produce much thinner layers that can be painted over after drying.
A distinction is generally made between products based on white spirit or alcohol based on their solubility. Intermediate varnishes with white-spirit base primarily have the task of smoothing out the indented areas that often occur in oil paintings. This refers to the dull areas of the picture when excessive¬ly thinned oil colours sink into the support. Moreover, these give tempera undercoats the nature of an oil colour. And of course they are used to protect oil paintings that are not yet finished.
Alcohol-based retouching varnish is used primarily by restorers as intermediate layer before applying retouches.
They have the advantage of not being soluble in the other solvents normally used in oil painting, in contrast to intermediate varnishes with white-spirit base. As a result, they allow a proper separating layer between the older original and new restored coat of paint, which can, however, be dissolved in alcohol (ethanol) again at any time.

By the way: all retouching or intermediate varnishes may only be applied after the picture surface has dried, i.e. after 4 weeks at the earliest.
ATTENTION: Alcohol-based products cannot be mixed with those based on white spirit. They dry much more quickly and also have a lasting dissolving effect on freshly dried oil colours. For this reason, pre-tests are always recommended!