Deep-coloured flat oil paints generally require preliminary application of a sealer. White and light tints can be used over most wall surfaces. In fact, they were first developed for painting directly over calcimine and wall paper, although this is no longer recommended because it may lead to difficulties at a later date. Flat oil paints have good application properties. They are often supplied under the so-called painters line of materials.
Oleoresinous finishes are fairly easy to apply.
They dry rapidly to a hard finish, provided the proportion of oil is not too high. Oleoresinous enamels have better alkali resistance than gloss paints or alkyd enamels, but they have poorer colour retention than the latter. Alkyds are the most widely used resin in coatings. Finish coats of all degrees of gloss should have good hiding power. Hence, they can be used over almost all surfaces except fresh plaster.