Tweaking White Underbase Settings for Better Performance

images of transfer paper and white underbase

When you are using the Digital HeatFX Print Optimizer software, there are several different options to choose from to improve the final look of your graphic.

One of those options is the White Coverage Underbase Percentage option, and there are good reasons why this setting is essential and why you would want to adjust it.

Ensures Proper Joining of A Paper to the B Paper

Getting the underbase correct helps ensure a successful marry of the A & B papers.  Our EZ Peel Paper is a two-paper process, and without the proper amount of white underbase, your B paper (the polymer sheet) may not correctly adhere to the A paper (the transfer sheet with the toner printed on it).

The magic number is a minimum of 200% on the white underbase. Your Print Optimizer software is preset to have the underbase at 200% as a default. Sometimes, however, you may need to increase this coverage percentage.

If you see that sections of the toner are not being picked up by the polymer, or if you see an overall frosted look to the image areas, you may need to increase the underbase percentage.

Working with Darker Color Garments

Underbase percentage is also important when you are working with darker colored garments.   You’ll want to make sure you have enough underbase so that the color of the shirt doesn’t bleed through your transfer image and shift appearance of the color on the shirt. 

A white underbase of 200% is perfectly acceptable when you are pressing the transfer onto a white or light-colored garment.  However, at times, 200% isn’t enough to make the colors in your graphics POP on dark clothes. If your colors appear washed out, it could be there’s not enough white underbase. In these cases, you’ll want to increase the “coverage underbase” setting to a higher percentage. 

You are essentially telling the software to lay down a higher amount of white toner behind your graphic.  The maximum percentage we advise is 300%. When the coverage underbase goes above 300%, the transfer can start to feel too heavy on the garment.

An Example

Here we’ve printed the same image on one sheet while increasing the “coverage underbase” percentage setting in increments of 25% from top to bottom.  

We see a range from a minimum of 200% to a maximum of 300%.

Tip: We have not yet married the A and B Paper in this example.  

You can do this yourself as a test if you need help with a particularly tricky image. 

Also, If your customer requests their graphic to be heat pressed on a darker colored garment, we recommended this technique to see the results of the graphic before you begin a big production run.  

You would want to make sure you have the underbase correct before you print up a bunch of sheets and then find out it may not look good on the particular garment you’ll be using.