How ink is made

The printer is an incredible piece of technology and has come a long way since the launch of the printing press. At a push of a button, you can have something which is on a screen printed off as a hard copy in minutes – sometimes seconds.

However, have you ever wondered exactly what goes into printing, and more specifically, the ink which helps us to achieve these printouts? We are going to delve into what goes into creating one of the most important parts of the printer and discover how exactly ink is made.

What is printer ink?

Ink cartridges are needed in an inkjet printer – and you probably don’t think too much about them until you need to restock. Each cartridge is filled with a liquid or paste (unlike toner which is a powdered substance). Then pigments or dyes are added that help to form the colours.

These are the two primary groups for ink: dye-based or pigment-based. The former sees colourants dissolved in a liquid (think food colouring in a cake mixture), whereas pigment-based inks use fine powder suspended in the varnish (the base of the ink).

Once upon a time, ink used to be made from natural colourings found in fruit and vegetable juices; the fluid produced by octopi and squid; and tannin from nuts and tree barks. Nowadays, Ink formulas vary depending on which brand you purchase and contain many different elements, but let us dive a little deeper into the makings of what keeps our printers functioning.

The science

Like anything which combines chemicals, there is a science behind achieving the perfect ink. It needs to be a perfect consistency and have the ability to dry and produce the right colour – this is no mean feat to achieve.

  • The base

With every creation, there is a base (varnish) to start with. For ink, this is mostly made up of linseed or soybean oil. A heavy petroleum distillate can also be used as the solvent. This is then mixed together with pigments.

  • The role of the pigment

The pigment, as touched upon earlier, is to help form the ink’s colouring. As well as the colour, pigments can also bring textures including a gloss to the forefront. It is also the element which can provide a resistance to light and heat. Pigments are a pivotal part in the creation of ink.

To achieve the full range of colours, printers use four main colours: cyan, magenta, yellow, and black. Mixed together when printing they can create a full spectrum of colours. Some of the newer printers also operate with ‘light’ versions of these to help improve the print quality. When the pigment is added to the base, it needs to be ground down to remove any lumps that have formed so the colours are spread evenly throughout the ink.

  • What else is added?

Dispersants are added to the ink to ensure the ink can flow well. These allow the ink to run smoothly and get transferred onto the page. As well as these, resins are added to the formula. These help to bind everything together – as well as providing the binding that enables it to stick to a surface when printed. Resins, including alkyds, ketones, acrylics, and formaldehyde provide the glossy look. More than one resin can be used in any one ink.

What is the difference between ink and toner?

There is sometimes some confusion between ink and toner. While both are used for home printing there is a difference. We touched slightly on one of the differences earlier, but as well as the substances which they produce, how they print onto the page is different too.

With an inkjet printer, little drops of ink are sprayed through tiny nozzles.

A laser printer uses toner. This prints onto a page using a fine powder made from polyester. The laser from the printer produces an electrostatic template onto a metal drum which rotates (this carries an electrical charge). The toner cartridge dispenses the contents onto the drum, with the toner only attaching itself to the specific areas where the laser changes the electrical charge.

Who knew there was so much science behind the creation of ink and printing? Now that you've learned what goes on behind the scenes you'll certainly appreciate every printout that you achieve at home and in the office.