How Ink Is Made
Anytime you see a printed page, whether it be a subway poster or a legal document passed around the office, you are looking at printer ink. It’s practically everywhere – in our books, on menus in restaurants, on the cups and napkins we smudge and grab and toss away. All that ink doesn’t just “appear” – it needs to be processed and manufactured. So how does that work?
Every ink is made of two components: a pigment and a vehicle. A pigment can be anything – it’s basically just a colored powder. The pigment is then incorporated into a vehicle – which can be any substance that absorbs and carries the pigment. Some vehicles are gooey, honey-like substances while other vehicles are very thin, like the thinnest water you can imagine.
The first step, then, is mixing pigment and vehicle. The vehicle is heated in a huge vat, and stirred quickly until it is much thinner than it would ordinarily be at room temperature. Then the pigment is added, turning it from a solid powder into a thin liquid.
The next step is called “grinding” – really it’s a dispersion process. See, all those little pigment particles are apt to clump and stick together in tiny little pockets of dry ink. Ink makers use different approaches to maximize the dispersion of those particles throughout the ink. Some stir thousands of tiny, steel ball bearings into their ink mixtures. The ball bearings break up those clumps of pigment and create a more vibrant ink. Others use a roller system that smears and spreads out the pigment as the mixture rolls through the assembly. Some use both systems to get a glossier, shinier ink.
The next step is quality control. When it comes to ink making, the most important quality is consistency. Ink makers will take sample batches and run comparison-tests: does each batch have the same color dispersion? Do the colors match up identically?
The final elements are then added. Stickiness (or “tack”) is measured. Tack determines how closely an ink will adhere to printer and how easily it will transfer to paper. Wax is added to some inks to make them glossier. A “drying” ingredient is added to make sure the ink dries quickly after printing. All of these important details come at the very end of the process.
For a beautiful example of ink making, try this video: http://www.youtube.com/watch?v=Fypi6dAJB8E