Oct 25, 20213 min read

What is eco-friendly ink?

In the good (or bad?) old days, this would be an article in a classical magazine (instead of an online blog).

You, dear reader, would be holding the sheets of paper in your hands and these sheets of paper would stapled or glued together and letters and pictures would be printed on these sheets in ink.

After perusing you'd probably toss the magazine into the waste paper bin and so it would end up in a recycling plant where it would be turned into new paper.

So far, so last century. But what happens to all that ink?

The origins

Historically, there were many attempts at finding materials which could be applied to what was then used as paper (papyrus, parchment, vellum etc.) in order to write or draw on it.

The ancient Chinese used soot as the basis of their recipes for what we now call ink.

The ancient Egyptians already used iron-based pigments such as ochre as the basis of their inks.

In medieval Europe, inks were made from iron-based salts mixed with tannins obtained from gall nuts, which are tumours of certain plants.

Nowadays, inks are made of either dyes or pigments and these dyes or pigments are dissolved or suspended in a suitable solvent.

As a rule of thumb, pigments are usually inorganic compounds (often metal salts) which are generally insoluble in water.

Dyes on the other hands are usually organic compounds, are often water-soluble.

Dyes and pigments form not just the basis of inks but of paints as well, so the market for them is huge.[1]

Environmental issues and paper recycling

Since dyes are generally organic compounds, they are typically derived from petroleum.

On the other hand, pigments are generally metal salts.

Both these classes of compounds have their lot of environmental problems attached to them, in particular with respect to water contamination.

In addition, dye-based inks often contain volatile organic compounds (VOCs) which evaporate and contaminate the atmosphere.

Paper recycling is essentially a re-pulping and re-casting process.

Waste paper is mechanically and chemically turned into pulp again and then made into new paper.

Leaving all the ink in the paper would yield a very dark-grey recycled paper (the older generation may remember the first recycled paper that appeared on the market).

In order to prevent this, a process called deinking is used prior to making new paper from the old.

Deinking produces significant amounts of waste, which is usually disposed of in landfills.

Pigment-based inks are usually easy to remove.

The pulp is washed with suitable solvents which leach the ink out of the paper.

Dye-based inks are more recalcitrant, and the resulting fibrous material may have to be bleached.

Circular economy?

In terms of circular economy, inks are a classic single use product.

However, even single-use products have to be produced in an environmentally friendly or at least acceptable way, they have to be designed so that they generate the least amount of harm to the environment during the whole product life, from the cradle to the grave.

Plant-based inks are available.[2][3]

The term 'Plant-based ink' generally means that the solvents the pigments or dyes are dissolved/suspended in are made from renewable resources.

These solvents make up approx. 60 to 70 mass% of the ink and may be made from soybeans, but other plants such as linseed (flax), castor, canola, and safflower as well.[4]

Things to look out for

If you would like to be environmentally conscious when printing makes sure you get recycled paper or, where recycled paper is not an option, paper from certified wood growers, which use environmentally acceptable practices.

Sourcing your paper locally may not be an option, at least not in Europe, where paper generally comes from Scandinavia.

As regards the ink, look out for the words 'vegetable-based' or 'soy-based' and 'low-VOC' or even 'VOC-free'.

Another aspect is the cartridge the ink comes in. These cartridges are generally made from plastic. They can and should be recycled/refilled. Empty cartridges may be handed in to the store where they were bought.[5]

There are many factors that influence sustainable printing.

We’d love to talk with you about eco-friendly inks and sustainable printing methods. Subscribe to our blog!