When you talk about screen printing t-shirts, you only need to remember these two inks to use – water-based and plastisol. There is quite a difference separating these two inks with their composition all the way to their respective applications. And I am here to explain these and more.
What are the pros and cons of using water-based ink and plastisol with screen printing?
Water-based inks pros:
- Vintage effect
- Eco-friendly
Water-based inks cons:
- Muted when used on dark colors
- Cannot get halftone and gradient results
Plastisol pros:
- Can work with all colors
- Compatible with all screen mesh counts
Plastisol cons:
- Not suitable for hand or vintage feel
- A tendency to crack and peel
There will be more information regarding these inks along with their respective characteristics and uses in this article. I will also share in the last part as to which ink I think is better to use.
Water Based Inks For Screen Printing
Water base is a system that requires both pigments and base. The pigments are added to the base to create the necessary colors. They use water as a solvent base to be able to carry the pigment.
These inks are used a lot in retail printing especially with soft shirts. They work by dyeing t-shirt fabric with the color of the ink instead of making the ink sit on top of the same fabric. They work best with 100% cotton material.
Water-based inks result in prints that can remain on the garment it is used on for quite a while. These same prints tend to be bright. And they also lend a feeling being a part of the t-shirt itself, especially after the first wash.
These inks are easier and faster to clean up when compared to plastisol inks.
After printing with this ink type, evaporation occurs which starts the curing process. Room temperature is enough to cure but for faster result, I suggest you run the print through a dryer.
You will have to allow a longer time to cure water-based inks. You will also have to set time for cleaning and setting up your screens again assuming that you did not manage to complete the print job within the day. This is so because you can’t allow these inks to dry on the screens.
Water-based inks have a shorter shelf life once mixed. The average time that it will last is about a week.
This type of ink requires some training prior to handling since the ink dyes the fabric itself. Knowledge of fabric types and their reaction to inks are critical.
Water Based Ink Types
There are two types of it: ready for use (RFU) and high solid acrylic (HSA) water-based inks. HSA is a newer technology created to solve issues with older models such as being thin and runny.
RFU comes straight out of the bucket and is offered in popular colors. They are already mixed and you can print them immediately on light fabrics or use a discharge underbase for more vibrant prints with dark colored fabrics.
HSA has thickening binder agents which allows it not to dry quickly on the screen and they can be stretched or stacked. This characteristic makes them ideal for complex prints such as halftones and simulated process. They still retain the soft feeling true water-based ink projects.
Water Based Mixing Systems
Mixing systems enable you to obtain control over these water-based inks through colors and ink mixtures management.
Pantone, a color matching system that is proprietary, colors can be also mixed using a color formula designated before. This system lets you produce a needed color and control its opacity level.
If you need to have better ink coverage, then you can simply add more opaque base and change the pigment ratio.
Water Based Ink Additives
You can have additional flexibility with water-based inks through its additives.
These additives will allow you to do further adjustments to the ink composition and properties.
Examples of these modifications include curing the ink at a lower temperature or enabling shops to use these inks even without any water-based curing equipment. These same water-based inks can also work with non-cotton fabrics through these additives.
Plastisol Inks
Image by squeegee_and_ink
They are composed of powder type polyvinyl chloride (PVC) resin and a thick clear fluid called plasticizer.
These inks don’t use water solvents and they require a high temperature to cure.
They are less pricey when compared to water-based inks and their prints almost always stay loyal to the design and are very bright.
They are quite easy to use for screen printing since they don’t dry up on screens and they can work with different types of fabrics. Once you open a plastisol ink, you would not need to close it for it would not harden. This is very convenient for projects that can span a number of days to complete.
Plastisol inks work well on “wet-on-wet” design printing where a layer of ink is printed on top of another after it gets a quick flash dry. There is little waiting time for this to happen.
These inks have a big number of specialty products that it can work with. They also work well with halftones and gradients.
Plastisol inks lend a heavier feel to the garment when used since they lay on top of the fabrics by covering the top layer. There is no breathability allowed here however, the prints are always bright. If prints using plastisol inks are ironed, there is a good chance that the design could smear or melt.
If improper curing is done, you will see poor washability, ink cracking, and loss of color with the prints generated. Setting a temperature higher than the recommended one (between 200-300F) will lead to a collapse of puff inks.
These inks do not work well with plastic, wood, glass, and metal surfaces since they wrap themselves around the fabric thus forming a mechanical bond. Also, they would not get along well with a nylon material that is waterproofed.
They also have a common tendency to print around the seams. Workaround this limitation by avoid setting your designs on the seams.
I would recommend that you run a sample print and test the plastisol ink for adhesion, bleeding, crocking, washability and opacity before you commence a production run.
Forms Of Plastisol Ink
These inks come in these two forms – an RFU (ready for use) and a system for mixing base and pigments.
Pantone’s are set in this system and you can easily follow formulas to create colors. Special effects such as shimmer, metallic, glow-in-the-dark, and suede can be recreated with these inks.
Plastisol Ink Additives
If you are considering using additives with your plastisol inks, I strongly suggest that you read instructions closely and follow what the ink manufacturers recommend.
Since the ink and additives are both chemicals, there is a good chance that there will be a wrong reaction borne out of this mixture. If there are too little or too many additives mixed in, this can have a serious impact on the print results which can affect your client satisfaction.
Also, do not add any mineral spirits to the plastisol inks for it may have an effect on the curing process.
Ink Recommendation
Finally, we are here and this is my final thoughts on the issue of using plastisol inks versus water-based ones.
Some prefer using water-based inks for there is a natural feel to it and it is very comfortable when worn because of the breathability allowed. Believing that print quality achieved here is higher compared to plastisol inks. It also helps that this ink is environmentally friendly to use.
Some shops like to use plastisol because of its cost and efficiency since you can resume working anytime after opening this ink. You need not worry about this same ink getting dry or performing additional screen cleanup.
Related Questions
Do water-based inks need to be cured?
Yes. The best way is to use conveyor dryers for faster curing. You can also use flash dryers and heat guns. After curing, you need to execute a trial print wash test to make sure that curing was properly done.
Is plastisol water based?
No. Plastisol is based on polyvinyl chloride (PVC) that doesn’t utilize a water solvent. You will need a high enough temperature (between 200-300F) to cause the PVC resin and plasticizer molecules to cure.
Is plastisol ink toxic?
Yes. Plastisol inks contain phthalates which are chemicals that are utilized to increase the flexibility of vinyl and plastic. There is not a lot of research yet on the exposure health effects of phthalates but a certain type of it, DEHP, is a proven endocrine disruptor and can cause cancer.
Is water based inks waterproof?
Water-based markers, which feature water solution, are not waterproof. To confirm this, you can create a swatch and then rub it or submerge in water. If there is a run, then this indicates that it is not waterproof.
