The purpose of a medium is to modify one or more properties of the paint and to make the paint suitable for a given application. Some of the properties are the consistency, gloss, fluidity, drying time, transparency and durability of the paint film.
Paint paste, popularly called paint butter, is a colorless, non-pigmented oil.
This medium can be mixed with oil paint in any proportion without changing the color or consistency of the paint. Thus, with a very expensive color, for example, you can make more paint.
In addition, it is also used to prevent the formation of cracks in certain colors applied in very thick layers. For this purpose, it is enough to mix in the ratio 1:1. The Paint Paste does not yellow and increases the durability of the paint film. The paint is more matt and the drying time somewhat shorter.
The binder used in acrylic paint and acrylic media is made up of a dispersion (distribution) of acrylic resin particles in water. As long as the binder contains water, the color will be white. When it dries, the water evaporates and the acrylic resin particles form a compact, transparent and colorless film, that is, the white disappears.
This is the reason why acrylic colors darken when dry. When mixed with a medium, the wet paint also lightens, but when dry it will have the same shade as the dry paint in its purest form.
A drier is a dilution of a metallic compound that speeds up the chemical drying process of oil paint.
Use very sparingly and minimize its use.
In general, it can be said that the use of driers should be kept to a minimum, since driers not only accelerate drying but also the aging process.
To avoid problems, never add more than 2% Courtrai Dryer to paints and never add more than 5% Harlem Dryer. In general, it can be said that the use of driers should be kept to a minimum.
Mediums are used to modify some of the paint's properties, such as build, gloss, flow, drying time, transparency, and durability.
Many painters only use water with their acrylics, but this doesn't always produce the best results. Mediums can be used to achieve better, longer lasting results with less paint.
Adding too much water can separate the pigment from the binder in the paint; the pigment is then unprotected on the painting and may lose color.