3 Ways to Enhance Plastisol Printing with FN-INK™ Extender Base  | Screenprinting.com

Have you ever grabbed a bucket of ink off the shelf and opened it up to realize that you don’t have enough to complete a job you’re working on? Yeah, it’s definitely not ideal. Well, if you have FN-INK™ Extender Base on your shelf, you’ll be a-okay. Extender base is a great ink to make your ink go further. But that’s not all the extender base can do. Want to make a vintage print? You can use an extender base to make it happen. Looking to add tonal effects to a design? Grab that extender base. The creative possibilities with an extender base are limitless. As with any new ink, it’s good to know the ins and outs of it before using the ink in production. Let’s dive in.


FN-INK™ Extender Base is a low cure, fully-finished clear ink. Basically, it’s FN-INK™ without color. FN-INK™ Extender Base has the same ink viscosity as regular FN-INK™ as well as that soft hand feel you’ve come to know and love. You can also add FN-INK™ Extender Base to other ink brands to improve the softness of the final print.

NOTE: FN-INK™ Extender Base is not a low bleed ink. Adding it to any ink that has low bleed properties will reduce that ink's ability to slow down or stop dye migration. 

Now you know the basics of what FN-INK™ Extender Base is and isn’t. Let’s go over how to easily add it to your production flow. 


Hands hold a print of a robot on a grey shirt


As mentioned before, there are a bunch of ways you can use an extender base. Let’s go over the details in a few of the techniques.


You can add as much extender base as you want to any finished ink. When used as an “extender,” you may not want to add so much that your ink loses any opacity or coverage. It’s recommended to add no more than 10-20% by weight—at least to begin with—into the color and print testing to ensure printed colors look correct. Once you know what adding an extender base will do to the ink, you can use more of the extender base. 

Here’s an example: say you need two gallons of black ink for a job, but you only have one gallon. However, you’ve got a gallon of FN-INK™ Extender Base sitting on your shelf. There’s no way you can get more black ink before the job is due. What do you do? Add an extender base to the ink.

Make sure to test what the prints will look like before you head to production. You’ll also want to clear the print with your customer. The more extender base you add, the less vibrant and dark that black will be. Make sure the customer is happy with the color before you move on.

Pro Tip: Adding FN-INK™ Extender Base to standard cure inks will help bring the cure temperature down. This is at a ratio of how much low-cure ink you add to the standard cure product. Let’s say your regular ink cures at 320°F. If you add 50% of a low cure ink (like FN-INK™ Extender Base) to it—which cures at 260°F—your cure temp will lower to 290°F, which is the halfway point between those two inks. If you changed that ratio from 75% low-cure ink to 25% standard cure ink, that ratio shifts to 25% of the cure temp. 


320°F @ 50% - 260°F @50% = 290°F cure temp

320°F @ 25% - 260°F @75% = 275°F cure temp

 a hand holds an ink spatula and stirs extender base in the bucket


If you’re wanting to create a color barely lighter than the shirt color, you may want to play around with an extender base to create a tonal ink. Tonal inks create a wash or watercolor effect and can add depth to a design. 

When mixing a tonal ink, start by adding 1%-4% of the desired color to the FN-INK™ Extender Base. Mix thoroughly and test it on a garment to confirm the desired effect. Add more or less color if needed. 

Print the ink through 200 mesh or higher with a hard squeegee, like a 70/90/70. The ink will slightly darken up all shirt colors to produce a consistent, darker tonal color (with a single ink).

A shirt with black ink and a tonal effect around the outside

Pro Tip: When printing Simulated Process, you may need to adjust the opacity of the inks. Use FN-INK™ Extender Base to create the translucency needed for optimal color blending on press.


To create a good vintage color, the ink should be a little transparent so the shirt color shows through the ink. Depending on the ink color, brand of ink, and type of ink, you may add as little as 10% or as much as 80% of FN-INK™ Extender Base to the ink to reach the desired effect. There’s no wrong answer. As long as the print looks exactly like you want it to, then it’s a win. FN-INK™ Extender Base will also help to create a soft hand print that helps enhance the quality of the vintage prints.

Reminder: While you can add as much FN-INK™ Extender Base as you want to ink colors, anything above approximately 20% will begin to cause a drop in opacity. Please be aware of this fact when mixing, and always test before production.



The ink is ready to print right out of the container, so no modification is necessary. If you’d like, you can modify it with a curable reducer at up to 5% by weight.

An image of a ship with a compass rose behind it on a white shirt


Since you will typically print thinner ink deposits when using FN-INK™ Extender Base, you may want to adjust and test the conveyor dryer to find the best settings. FN-INK™ Extender Base is a low cure product, but it remains stable at higher temperatures. The base can be used with standard cure inks of 320°F. Since FN-INK™ Extender Base is a low cure ink, it will bring down the cure temperature when added to products with a higher cure temperature. The number of degrees the extender base can bring down the standard cure temperature depends on the proportions to which it was added. 

Again, FN-INK™ Extender base is not a low bleed ink. Adding it to any ink that has low bleed properties will reduce that ink's ability to slow down or stop dye migration.



When testing cured ink, perform a wash test to ensure proper cure prior to going into production. Soft-bodied inks can penetrate into the fabric, thus making them take a little longer to reach full cure temp.

When inks penetrate into the shirt fabric, they do not trap shirt fibers well. As a result, shirt fibers can come loose when washed and poke through the print, causing the print to look faded. This is normal and not an indicator that the ink is not cured. Undercured ink will look faded or can wash out.

Inks made and printed with FN-INK™ Extender Base tend to be used in designs that are printed very thin, so a stretch test is not going to be accurate as very thin and soft ink deposits do not stretch well. A wash test is the only way to ensure a proper cure.

A hand holds a bucket of extender base with a scale in the background

You can use an extender base for far more than just extending an ink’s life during a print job. Create tonal prints, vintage, etc. with just one ink. The only limit is your own imagination.

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