What is Printer Ink Made Of?
We use printer ink every day, but we only ever think about it when we have to change cartridges. How annoying! Sometimes we spill the ink. In that case, we’ll definitely be thinking about it.
The thing about printer ink that we don’t normally consider, even when we’re changing cartridges or cleaning up a spill (Ugh!) is what our printer ink is made of. Is it toxic? Why is it so expensive? Is it made of gold? Spoiler alert: It’s not.
Basically, printer ink is made from either organic or inorganic pigment (depending on the type of ink), which is dissolved in a chemical solvent, similar to paint. Now, you probably have some questions about that last sentence, particularly about my vague use of the words “pigment” and “chemical solvent,” which of course have their own unique compositions. In order to decipher these terms and get to the bottom of what printer ink is made of, we have to go back to when ink was first invented.
By examining how printer ink used to be made, we can better understand how it is made today, and what it is made from.
What Did Printer Ink Used to Be Made Of?
Back when printer ink was first invented, it contained natural ingredients. Like, really natural.
Originally, printer ink was made from...
Tannin from nuts and tree bark
Vegetable and fruit juices
Cephalopod secretions, such as from octopi, cuttlefish, and squid
Nowadays, printer ink is made from more processed, chemically-created ingredients that are far from natural.
What is Printer Ink Made of Now?
Printer ink today is made primarily from carbon black, a pigment similar to soot. Carbon black is made from a plethora of additives, including chelating and drying agents, and it’s held together by binders and solvents. The ingredients can vary slightly depending on the brand of printer ink (i.e. HP, Epson, Canon), but you can usually find the same ingredients in most printer inks.
Let’s examine some of the specific ingredients used to produce printer ink.
The type of pigment used in ink determines its color and surface texture (glossy or abrasive), as well as its resistance to heat, light, and certain solvents. One type of pigment called base pigment is mixed with other chemicals called opacifiers and extenders. Opacifiers are white and extenders are clear, so when the two are mixed with carbon black, they make the ink more opaque, thus changing the ink’s color from black to gray. Also, the surface of base pigments is glossy.
Dispersants are an important ingredient in printer ink, because they allow the ink to flow and not clog so easily. Essentially, dispersants stabilize pigment particles by decreasing their mechanical energy levels. To decrease the mechanical energy of a pigment, ink manufacturers add surfactants and polymers to ink while its suspended in a solvent. Surfactants and polymers absorb pigment particles and determine the thickness of the ink, which affects how easily it flows while in use.
Resins bind ink together to create a distinct film, and affect how ink is applied to a print surface. Resins also affect the rheology and mechanical properties of the ink. For example, resins like alkyds, ketones, acrylics, and formaldehydes result in glossy ink that is resistant to either heat, water, or certain chemicals depending on the resin’s composition. A resin’s composition can vary from brand to brand, and there are usually multiple different resin’s added to a single ink type.
Some of the other common, but less impactful ingredients found in printer ink include...
Humectants, which slow the aging of printer ink.
Defoamers, which regulate the frequency of bubbles and foam.
Wetting agents that determine the ink’s surface texture.
Amine derivatives used to modify the pH levels of ink.
Biocides and bacteriostats, which prevent bacteria and fungi from growing.
Ingredients in Printer Ink Colors
As we discussed previously, pigments in ink determine the ink’s color. Different colored pigments, then, create different colored printer ink, and so the color of ink provides insight into what a specific printer ink is made of.
Black Printer Ink
Black printer ink is made from carbon black, and its opacity is altered by the addition of white pigment made from titanium dioxide. These ingredients can be used individually or mixed with other pigments to alter the color of the ink. Black ink, for example, is typically created by combining carbon black and varnish, however, white pigment can be mixed into black ink to make more of a gray color.
Traditionally, there are four different colors used in printers: Cyan, magenta, yellow, and black. These colors are mixed together in different proportions to make additional colors on the spectrum for full-color printing. Newer printers, on the other hand, carry a wider variety of colored inks and can produce higher quality full-color prints. Basically, the accuracy of the colors in newer printers is vastly improved over older printers thanks to their wider variety of compatible colors.
Color Printer Ink
Color pigments, used to create colors of ink besides black and white, are made of salts and dyes. Some common printer ink colors produced by salts and dyes are peacock blue, yellow lake, diarylide orange, and phthalocyanine green. These are considered “organic” inks.
Inorganic inks are less commonly used than organic inks, but some of the most important inorganic ink colors are chrome green, prussian blue, cadmium yellow, and molybdate orange. These colors of ink are created from a mix of molybdate, sulfate, and lead chromate.
Why Is Printer Ink So Expensive?
After reading about what printer ink is made of, you may be wondering which ingredients are responsible for the high prices of printers and ink cartridges. The price of printer ink, particularly from popular brands, has risen in recent years (controversially), but it seems the rise in ink prices has more to do with the cost of its development. Lucky for you, we know some ways to save money on ink.
If you’ve already bought ink at a high price, you can sell your unused cartridges online and use the money to buy cheaper ink. Now that you know about the ingredients used to create ink, and how common they are across ink manufacturers, you can rest assured that you will be getting high quality ink from cheaper brands.