I'm not sure what kind of "regular" ink you have in mind, but screenprinting ink can be applied to dark shirts; it just generally benefits from doing a couple of layers or a white underbase.
In general for all types of printing, a garment is considered a dark garment based on the lightest color in the graphic if you want to keep true color reproductions. The key is that the color of the garment needs to be lighter than the lightest color in your graphic. If you graphic has white in it, you need to use a white underbase on any color shirt besides white if you want accurate color reproductions. Hope this helps.
I have been using speedball screen printing ink to do some shirts at home. I noticed they had the same ink but called opaque and a little more expensive in the store.
I noticed they had the same ink but called opaque and a little more expensive in the store.
That's for printing on darker colours.
Quote:
Originally Posted by aokusman
What is underbase?
Same principle as painting a wall: if you want to paint a black wall white, you need to give it a few layers because it will show through if you just paint it once. Likewise if you want a nice crisp white on a black shirt, you need to print more than one layer of ink. Often you use white for the bottom layer, then print your colours over the top of that, but you can just print the final colour more than once.
Which colors are considered dark 
) - two ought to do it.
