In paintings, a binder (or medium) is the material that holds the coloured pigments together to form paint. In paintings at the National Gallery, this is often a drying oil, but may also be egg yolk or animal glue.
In paintings, a binder (or medium) is the material that holds the coloured pigments together to form paint. In paintings at the National Gallery, this is often a drying oil, but may also be egg yolk or animal glue.