What is the Most Sustainable Ink?

What is the Most Sustainable Ink?

Jan 22nd 2020

We often get the question: Are your inks soy-based? or Are your inks vegetable-based? or Are your inks water-based?

I believe what people are asking is: Are your inks eco-friendly?

The answer is...complicated. 

The truth is that there is no ink available today that is 100% free of non-renewable resources or chemicals. 

But we have come a long way since the 1970's. Inks contain a few different components: pigments (what gives the ink its color), additives (that improve performance, drying time, resistance to smudging, etc), and carriers (the vehicle that transfers the ink onto the substrate that then dries off leaving only the pigment and additive behind). Carriers account for 70-80% of a bucket of ink. Pigments account for 10-20% and additives account for 5-15%. 

In the 1970s, most inks had petroleum-based carriers and were referred to as "solvent-based inks." When solvent dries, it releases volatile organic compounds in the air, which leads to  poor air quality and adverse health effects for print workers. Petroleum-based inks also require print shops to use harsh cleaners on their printing plates and equipment, increasing the amount of VOCs emitted. 

A combination of oil shortages and the EPA's Clean Air Act of 1970 led the printing industry to transition many historically solvent-based inks to vegetable / soy or water based inks. These new inks featured carriers that were plant or water-based, though the additives and pigments largely remained the same. 

In most cases, when soy or water-based inks dry, they emit very few (sometimes zero) VOCs. Print shops that have made the transition to soy or water-based inks typically report much better air quality and working conditions for their employees. It is also important to note that just seeing a soy-based ink label does not necessary mean that the carrier is 100% soy. Depending on the type of ink and its intended use, an ink’s oil content must be a minimum of 6% up to 40% soy in order to qualify for the Soy Seal logo. The mix of soy oil with petroleum oil would impact its level of VOCs emitted. 

Choosing Between Water versus Soy/Plant-Oil Based Ink Depends On Some Factors

There are a LOT of variables when it comes to printing. 

First is the printing method, of which the most common are flexographic, offset, offset lithographic, digital toner, digital inkjet, screen printing. 

Second is the printing substrate, which varies wildly. Uncoated paper and corrugate, coated paper and corrugate (which also ranges from clay coated to plastic coated), plastic, glass, aluminum, cotton, wood, silk...the list goes on.

For example, offset lithographic printing on paper (the method used to print newspapers) can utilize solvent-based or soy-based inks. Since the 1970's, newspapers have in fact been largely printed with soy-based carbon black ink.

Flexographic printing on uncoated paper can utilize water-based or solvent-based inks. When running coated surfaces or poly materials on a flexographic printer, water-based is possible but can be extremely difficult. In these instances, some print shops actually utilize a UV curable ink, which does not contain any carrier at all (because the ink is cured rather than dried). 

Digital ink jet inks are typically solvent-based or water-based.

Screen printing inks can utilize solvent-based inks, soy-based inks, plastisol inks (which are cured), water-based inks (though water-based inks can be very difficult to use!), a decision that varies based on the substrate and drying / curing process.

What To Ask And Look For

If you don't know what kind of printing method your printing partner is using, we recommend asking this question: "Please share more information about your inks and what steps you've taken to making them eco-friendly?"

Alternatively, you might start the conversation by asking about the printing method and substrate being printed, to help you research sustainability considerations and the types of ink that you'd want to see used for your project.

Ultimately, look for ink with a carrier that is either water or soy / plants-based (deciding between the two will be dependent on the printing method and substrate) and that emits as few VOCs as possible. 

Some companies have ink options and can help you understand the functional and sustainable pros and cons of their options. Other companies (like us) have specific inks identified for different use cases. Your print shop can then explain what kind of printing method they utilize, what kind of ink is being used for your specific project, and why it has been chosen.  

Our Comprehensive  Bill of Materials provides extensive detail on the ink types used for both inline and post-production printing on our various lines of sustainable packaging. But, in almost all of our printing, we use some type of low or no VOC water-based ink. The two main exceptions are the EcoEnclose logo on our Paper Apparel Mailers and our We Care Cards, which are both run through an offset press and utilize low VOC soy-based inks. 

The Move to Algae Ink

All of this discussion around soy and water-based inks deals with the ink's carrier alone. 

Our  algae ink, developed by Living Ink Technologies, is one of the first real innovations in the ink industry in the past few decades. 

Instead of petroleum being used as the basis for the black pigment (the vast majority of black print ink is carbon black, derived from fossil fuels), algae ink's pigment is derived from renewable algae cells (that are actually a waste product from an algae biofuel operation). 

We have been offering water-based black algae ink as an option for all of our branded boxes for several years, at absolutely no additional cost to you. Soon, we anticipate being able to offer black algae printing ink on all of our mailers as well. 

If you are looking for the most eco-friendly printing ink out there, we encourage you to look at algae ink.