Alcohol inks are an extremely thin artist's pigment. They are designed for use on shiny or non-porous surfaces and will stick to practically anything.
They resemble oil paints in the sense that a solvent is required to blend one or more shades together, but often colors are mixed without because of the strange, random patterns that are created. The consistency allows for the use of some innovative techniques but requires special tools.
It makes logical sense to use inks in a pen, but alcohol inks are more versatile. The pens are of a very simple design, consisting of a reservoir for storing ink and basic fabric nib that transfers the ink to the drawing surface via gravity.
The flow of ink through the nib can be controlled with hand pressure, allowing for the creation of wells and dark spots in designs. Different nibs are available, with broad, soft brush tips for washing and painting and small, pointed nibs for writing and fine detail.
Felt is used in place of paintbrushes for applying the ink to surfaces. The low viscosity of alcohol inks makes them very prone to dripping from utensils.
Felt ink applicators combat this by using a wad of spongy felt in place of bristles. The absorbent pad sucks up the ink and holds it inside until the felt is pressed against the drawing surface, squeezing it out.
A popular technique involves applying different inks to the drawing surface, then blending them together using blending solvent, applied to a felt brush. The solvent causes the ink to break down and mix, and the felt allows precise control of where and how this can happen.
Alcohol inks can be used on traditional drawing media, such as canvas, paper or silk, but they excel on glossy, non-porous surfaces, such as glass or plastic. The low viscosity of the inks is an important characteristic; it is so thin that it will run into all the tiny grooves and depressions, creating dark pools and channels of intense color.
It is common to choose materials with irregular surfaces, or even to roughen smooth surfaces, to give the inks a more dynamic surface to adhere to.
Stamping is a popular use for alcohol-based inks because of their vivid colors and tendency to stick to any surface. Spray bottles and atomizers are also an option because the ink's low viscosity make it easy for the ink to pass through the nozzle of a spray bottle, allowing colorful mists to be created.
Blending solution is an essential because the solvent allows the inks to break down and blend together. This is essential if you plan to mix colors; otherwise, the inks will just spiral around and remain as two separate colors.