Most colored inks are carefully formulated to meet every requirement except that of permanence of color and can never be relied upon for other than temporary results. This is due to the fact that most drawing inks are made from dyes. This includes printer inks. The length of time ink may hold its true color will vary on the exposure to the elements and ultraviolet light. However, dyed inks often are much more vibrant than pigmented inks and tend to reproduce well.
Pigmented inks are usually thicker and more opaque due to the nature of the pigments themselves.
Because pigments are usually natural elements derived from various sources, the individual particle weight will vary therefore pigmented inks often do not mix well with each other. A few manufacturers are responding to artists growing concern for archival materials and are making inks with permanent pigments. Shellac and borax used as a binder create inks that dry to a permanent finish. These inks are not soluble with water once dry. Denatured alcohol is a solvent for shellac therefore may aid in clean up of shellac based inks.