Screen Printing:

The Basics of Water-Based Inks

By Nathan Foster, Contributing Writer

April 8, 2019

If you’re in the screen-printing industry, you’ve probably been hearing about the benefits of water-based ink: the softer hand, the minimal environmental impact, the eradication of toxic byproducts, the long-lasting and breathable comfort, the vibrancy of colors and designs.

The benefits sound great, but if you’ve heard the good things about water-based inks, you’ve also probably heard some of the bad things too. The good outweighs the bad, however; so, you’ve decided you’ve heard enough and you’re ready to give it a go.

As someone who has devoted a lot of time to the trial and errors of this printing process and has transitioned large-capacity print shop from all plastisol to over 80% water-based printing, I’ve compiled a couple of thoughts that I wish I’d asked myself before starting:

The Motivation
Why do you want to print with water-based inks? This can be a very challenging and humbling process. Not to be dramatic, but a lot of people who try it out don’t stick with it because when it gets challenging, they don’t have a solid reason to persevere. Whether you are just starting your screen-printing adventure or you’re a seasoned printer, water-based inks will challenge you, so identify your reason for starting. Do you want to have less of a detrimental environmental impact? Are you looking for a softer hand print? Have you mastered plastisol and need a new challenge? Are your customers clamoring for it? Whatever your motivation is, determining the “why” from the beginning will sustain you to success through some of the inevitably frustrating parts of the process.

My Why: I love to learn, so when I was given the opportunity to learn everything I could about water-based printing I jumped on it. I dove right in and learned everything through trial and error (and next month’s issue will go into nitty gritty detail about some of those errors to help you avoid making the same ones!). Before I dove into water-based inks, I was burned-out on screen printing. Every day felt the same and I was just printing to pay the bills. Printing with plastisol worked, but it wasn’t challenging or creative and I was bored. Granted, plastisol can be very challenging in its own way, especially if you want to do it right. But water-based inks were just different. I loved learning about the science behind them and exploring what worked and what failed depending on the garment, the ink, and the process.

The challenge and creativity is what motivated me at first, but I remain motivated and inspired by the tangible benefits of the actual ink beyond the intrigue of learning a new process. As the head of production, I love how much easier it is to clean with chemicals that are safer and more degradable, and I feel good about my 40+ team members handling non-toxic materials on a daily basis. As a business person, I’m proud of printing a superior product that customers truly appreciate and enjoy – our shirts are the first thing people reach for in their closet, because we give them their softest and longest-lasting t-shirt. And as a conscientious human and father, I feel good about reducing the amount of plastic that ends up in landfills and minimizing our environmental footprint both today and for future generations.

The Standards
What does quality control look like? Are you loading, pulling, and catching at the end of the dryer? If so, be sure to stop often and check how your prints are looking. But beyond that, put checks in place for every step of the process, not just for the finished product at the end of the dryer. Mistakes and variables occur at every stage in production, so you’ll need to have a series of checkpoints to help you trouble-shoot and problem-solve. Each mistake is a learning opportunity, but it’s hard to adjust what you’re doing the next time if you’re not consistently monitoring your processes each time. Once you get into water-based printing, your quality control processes are either going to be the most helpful tools to help you progress or the most frustrating deficit that keeps you from getting better.

A key factor in quality control is ensuring that you have the correct type of emulsion. I do not recommend using your normal emulsion then hardening it: this will most likely fail. Instead, get a good dual cure emulsion to test with. Some dual cures work better with different water-based manufactures. Some are made for discharge printing and some are made for high solids. The chemistry can be very different, so work with your vendors for samples to see what works best for you depending on the products that you choose (more detail below).

The Products
What type of water-based inks do you need to print with? What do your customers need? There are so many different types of water-based ink systems: for almost any type of application you have there is a water-based version of it. Some systems work better than others, and some are much more beginner-friendly than others. It’s worth your time to do your research and get other printers’ feedback and experiences with different systems while weighing what your own needs are before you make purchases and start printing.

The different types of water-based inks are HSA (High Solid Acrylic), Discharge (my favorite!), Low-solids, Medium Solids, Wet on dry, wet on wet systems (new and pretty challenging). Each system has a unique set of techniques to successfully get a job done, in next month’s article, I’ll go into more detail about the pros and cons of each.

The Capacity
Before you begin, take inventory of where you’re at and what you have. Factor the answers to all of the following questions into your decision to start printing with water-based inks. What are your capabilities? How long have you been printing? Do you have an automatic or manual? Are you curing your shirts with an electric, gas, or hand dryer? How many shirts do you plan on running? Does your screen room have a successful system already in place? Thinking through these questions will help you troubleshoot before you start and assess what you may need to get you through the transition.

Water-based printing seems overwhelming because it is. You won’t perfect water-based printing immediately, so give yourself plenty of time to get familiar with the process. But maybe that’s what makes it so rewarding and worthwhile: water-based inks can never be exhaustively mastered, and so there’s always a new horizon to explore. Never stop learning.

Nathan Foster has been in the screen-printing industry for nearly 20 years, working in every aspect from production to sales. He is now the vice president of production at B-Unlimited, Fayetteville, Ark. He oversees a department of more than 40 full-time team members and specializes in printing and production workflow with water-based inks. Through years of learning through trial and error, Foster has led B-Unlimited’s transition from primarily plastisol printing to nearly all water-based printing. An educator at heart, Foster is the key presenter at ORIGINS: A Journey in Water-Based Printing.