Although many people associate ink with pens and printers, there are many other kinds. From a cake with your face on it to a temporary tattoo your child got at a birthday party, different inks were used to create those images. Whether you use erasable, glow-in-the-dark, or invisible ink, you can find it everywhere and on everything!
A Brief History of Ink
Ink can be traced back as far as 40,000 years ago! In fact, ink has been around since the dawn of communication with cave paintings being the first documented use of ink in history. Originally, ink was made from different combinations of animal fats, fruit or vegetable juices, and plants. Now, most are made synthetically in factories with pigments or dyes.
Glossary of Ink Terms
Ink has a lot of confusing ingredients, but it doesn’t have to be that way! To break down ink formulas even more, we’ve come up with a list of the most common ink terms and definitions so that you know an additive from wax and everything in between.
Additive: A substance added to ink to prevent ink from drying out or separating overtime. Other inks, like edible ink will have additives to prevent spoiling.
Colorant: A dye or pigment added to a material, such as ink, to give it color.
Drying Agent: A chemical used to ensure ink dries once it meets a surface, like paper.
Dye: A type of colorant that dissolves completely in a liquid without additional help.
Insoluble: The inability to dissolve completely in a substance, such as water.
Linseed Oil: A colorless to yellowish oil extracted from dried, ripened seeds of the flax plant. Also known as flaxseed oil.
Pigment: A type of colorant that’s unable to dissolve without the help of a vehicle.
Soluble: The term used to describe a substance that’s dissolved completely within a liquid.
Solvent: The liquid to which the colorant is added.
Soybean Oil: A common vegetable oil extracted from the seeds of the soybean plant.
Vehicle: The binding agent added to pigment allowing it to dissolve within a solvent.
Wax: A substance added to ink to increase rub-resistance, so the ink doesn’t rub off of its surface.While there’s a bunch of ingredients that make up ink, the colorants are what gives it such beautiful colors! Without dyes and pigments, everything would be completely colorless. The other ingredients are just an added bonus to make sure the ink works in tip-top shape! What’s the Difference Between Dyes and Pigments?
The biggest difference between dyes and pigments are how they react when applied to a base. For example, dyes dissolve completely in liquid and change the chemical structure of its solvent, while pigments are unable to dissolve without the help of a vehicle. Solvents are liquids like water, oil or milk, and have the ability to dissolve other substances.
See Colorants and Solvents in Action!
Of course, you wouldn’t use milk to make ink, but to better understand what a solvent is, let’s talk about chocolate milk and how it’s made. You start by pouring milk into a glass. You’ll notice that its color is still the same, but once you add chocolate syrup to the cup, it begins to mix a little bit with the milk. That’s because the milk (solvent) is dissolving the chocolate syrup (colorant) even though it hasn’t been mixed yet. Once you stir the two ingredients, the milk changes colors from white to brown. Since there are no other ingredients inside the glass and the chocolate dissolved, it’s safe to say that the syrup is a dye colorant.
How Ink is Made
Back in ancient times, ink was made by muddling ingredients together in a basin or bowl. Muddling is a technique that breaks up fresh ingredients, like herbs and fruits, so they can bind better with a liquid or paste.
In the 21st century, however, most inks are synthetic and made in large factory plants. This ensures the quality and color of the ink is the same every time it’s used. Once the ingredients arrive at the factory, the ink is mixed and processed, and then shipped off to a printing facility or distributor.
From a powder to a liquid, learn how ink is made in these easy steps:
- Step 1: The vehicle is weighed, transferred to a mixer, and heated by mixing. This process is necessary to make the product thinner than it normally would be at room temperature.
- Step 2: Once the vehicle is thinned out, the pigment is added to the mixer. Every pigmented-ink starts as a finely ground powder and comes in a variety of colors. Most ink makers use the CMYK model, however, ink makers, especially in the screen printing business, are not subject to only these four colors.
- Step 3: The smooth, blended product travels from the mixer to a transport cart.
- Step 4: When the pigment is first added to the vehicle, some pigment particles stick together and form lumps. The ink is loaded up into a bead-mill machine, which is filled with tiny steel balls. When mixed, the balls break the pigment particles apart into tiny pieces and create smoother ink.
- Step 5: After the ink is smoothed out, it goes through another machine called the three-roller mill. This machine is made up of 3 steel rollers that run in opposite directions. It smears the particles in the pigment even further apart and gives the ink the most color strength (the colorant’s ability to change the color of a colorless material) and a high gloss finish.
- Step 6: Now that the ink is fully incorporated, it will go through a series of tests for quality control. The tests ensure that the ink is the same from batch to batch.
- Step 7: Once approved by quality control, the ink is taken to another mixer. This is where extra ingredients such as waxes, drying agents, and other additives are mixed in.
- Step 8: Next, the ink is run through the three-roller mill again. By repeating the process, the mill removes any final air pockets from the ink. This polishes the mixture and makes it even glossier.
- Step 9: Finally, the ink is ready to be packaged into smaller containers. Once sealed up, the containers are given a label. From there, the ink is loaded up into trucks and ready for their next destination.