Because of their permanent, water-resistant properties, industrial printer inks are oil-based, but the machines are expensive and not always suitable for smaller office setups. There are two types of ink available for a general desktop printer: oil-based pigment and water-based dye. Both contain a colourant, a solvent, and bonding additives, but there are differences in how these elements interact and deposit on paper that have a direct impact on water resistance, colour saturation, and overall print quality.
Pigment-Based Inks
Before being applied to paper, pigments must be mixed with a liquid. Pigment dyes, like industrial printing ink, are typically oil-based for their water- and fade-resistant properties, which are especially useful on slick surfaces such as transparencies and glossy brochures. Pigment dye printers apply a layer of colour on top of the page rather than absorbing it into the paper. The printer uses a combination of heat and pressure to evaporate the liquid and permanently attach the pigment to the paper after the pigment particles and solution mix coat the paper.
Dye-Based Inks
Water-soluble dye-based inks mean that the colour is fully dissolved in the water mixture rather than being stored as tiny crystal particles. Dye-based ink is distributed in the same way that pigment inks are, with the printer laying down the ink solution and then applying the same heat and pressure to dissolve the liquid, but the dye-based ink is left bonded with the paper, absorbed within rather than coating the surface.
Permanence
According to Wilhelm Imaging Research, a company that publishes printer permanence data, some dye-based inks degrade within two years of printing, though some manufacturers have managed to produce much longer lifespans (up to 100 years) if stored and displayed properly. Similar research indicates that pigment-based inks can last for more than 225 years.
Water-Solubility
Because dye-based inks are water-soluble, they are susceptible to moisture damage. A single drop of water will dissolve and mix the ink, and humid environments will cause the dye to evaporate faster. The oil-based crystal makeup of pigment inks, on the other hand, is unaffected by water, making it ideal for printed pieces that will be exposed to the elements or documents that will be archived for a long time.
Color Depth
Because water-soluble compounds are also added for optical enhancement, the colourants in dye-based inks produce deeper blacks and more vivid colours than pigment-based inks. This makes them suitable for photo printing, which relies on vibrancy to bring out the details in a photograph. Pigment-based ink, on the other hand, is more resistant to smearing because it sits on the surface rather than being absorbed into it. Graphics with sharp colour differentiation are better produced with pigmented ink because it has a better blending effect than dye-based ink, which causes colours to dissolve and smear into each other.
Cost
The materials and production of dye-based inks are much less expensive, and the ink is much more widely available in stores. Pigmented inks are more expensive to produce than dye-based inks, so they are more expensive. However, pigment-based inks are becoming more common, which means that prices will begin to fall.
