As you may already know, discharge screen printing has traditionally been used and made for 100% cotton garments. But reading over industry forums I've seen numerous people post the questions "Can you use discharge ink on a 50/50 blend shirt?" The answer is yes! Sort of. Sometimes. I know that's not the most cut and dry answer. But there are certain situations where you can print discharge ink on 50/50 cotton poly blends and get great results and there are times where the prints are not that great. So let's go over the different scenarios where it works and doesn't work.
When printing on solid 50/50's colors the discharge ink will discharge the cotton but not the polyester. So the end result or print is that the colors are often described as being muted or of having a vintage distressed look. But we when we use discharge ink on certain "heather color" we have much more success in achieving a bright vibrate print.
Colors that are very difficult to discharge, whether they are 100% cotton or a blend are- Kelly Green, Turquoise, Purple, and Royal blue. These colors are dyed with very resistant reactive dye.
Trying to achieve exact pantone colors using a discharge ink with pigments is very difficult process .So if you do need to make an exact pantone color match avoid using discharge ink on cotton poly 50/50 blend shirts.
The first scenario or method used when printing discharge ink on 50/50 is to print strictly discharge ink with color pigments added ink the ink to create the desired colors in your design. This method will give you the softest "hand" possible. But again, the colors are not always bright and vibrant. However, we have found that some "heather colors" work very well. This is especially true with a dark heather grey.
The second option of printing discharge ink on 50/50 or tri blends is using discharge ink as you're under base and then print either water base or plastisol inks on top. The way printed with this technique was to print the discharge under base, flash it, and then print plastisol colors on top wet on wet. You will not always be able to see the design. Often you will only fully see the print after the garment has traveled through the conveyor dryer and the discharge ink has fully discharged.
We also recommend that you use straight discharge ink as the under base, no pigment. This will help the water base ink to achieve a better opaque color. By using plastisol ink you can achieve a much more correct pantone color match. The hand or feel of the shirt will not be as soft as discharge only. But you can use a soft hand additive for the plastisol to keep the hand and feel as soft as possible. We also add a matte additive to keep the plastisol from having a shiny look.
It is highly recommended that you use a forced air flash dryer and forced air conveyor dryer. Improper adhesion can often result in the design flaking or washing off the garment.