Hello Angel,
No doubt you are having issues with your inks. Its hard to pinpoint why since I've never used the brand you mention. Here is just how I look at both waterbase and discharge printing, curing and analysis:
Discharge - I never underbase. All art is separated 'butt to butt' with no overlap unless I want some colors to mix wet on to wet for secondary colors. Anytime I have put a discharge underbase down and discharge on top, the colors do not come out as vibrant. I prefer to use the pigment of the ink for color, and as stated here too much will not bind properly no matter how much I cure it.
The only time I use a base is if I am placing
plastisol over a discharge base to achieve a soft hand. No wash issues here, but curing can be a challenge in a small oven.
Waterbase: Same as Discharge, separations are butt to butt, unless I want to overlay and allow the colors to mix during the print process wet onto wet.
The discharge print on inexpensive dark garments can be back dyed by the shirt dye. Black and navy shirts that have not be completely rinsed in fabric manufacturing can cause the print to be duller after washing. Not as much an issue on waterbase since it is printed on lighter grounds. In the near future Acrylic Waterbase inks will be the rage. They print like waterbase, have incredible soft hand, and opacity equal or greater than plastisol.
Fibrillation is my biggest enemy with waterbase, or discharge to a lesser extent. If you print with fine meshes above 180 the print may look fine, but after washing the fibers in the shirt stand up and lessen the amount of color. Saturation of the fabric using S mesh with more open area, or lower mesh counts for solid areas can fix this, but not eliminate the issue on fuzzy ring spun shirts with longer fibers.
Fabric weight also plays a part in how well a shirt discharges. A 4.8oz 24 singles fabric is much easier to create detailed discharge than a 6.1 oz Ring Spun 14 or 18 singles weave. The 4.8 can use finer mesh with less ink laydown than the 6.1 oz.
In my exeperience a 20 ft gas fired oven is needed to handle the load of 1-2 auto presses since the shirts need to cure for 1.5-2 minutes. When your shirts come out of the oven rub the printed portion onto a white piece of fabric. If you see color transfer your oven temp/time is out of whack. Slow the belt down, make sure you have fresh filters, and the oven is maintained for maximum airflow. No pellons stuck in the blower area, all jets free of clumps of shirt fibers, your flame in the inspection window is blue not yellow.
If you are using an electric oven with limited air circulation you can create a print that feels dry, but in reality not all binder is cross linked, not all water is completely evaporated from ink film. You can post cure in a transfer press, but this needs to be done immediately as it comes out of the oven and is only a fix not a good long term solution.
Alan Buffington
Murakami Screen USA
www.murakamiscreen.com