Screen printing T shirts

Question

I am designing a shirt logo. I have extensive experience with screen printing on paper, but I am unsure about a few things for shirts. Can I print a highlight colour over a darker previously printed colour?

I am used to printing from light to dark on paper, but am I correct that I could reverse that on shirts? For example, if the image were a STOP sign, could I print the red and then the white on top?

You lose fidelity with the inks that I use on paper, so I would normally do this with white first and then red over top (just as an example of a very basic image).

Thank you very much for the help!

Answer 1

There are two main types of ink used when screen printing textiles: water-based and plastisol.

If you are using water-based ink then the answer to your question is no.

Plastisol inks are PVC based and can be completely opaque. They're also very easy to work with. Plastisol inks don't actually dry, they need to be cured at a high temperature and therefor can melt if they are heated to that temperature again (that's why you can't iron some screen printed t-shirts).

Water-based inks also won't show up opaque on dark colored fabric where plastisol inks will (better at least, it depends on the ink and color). If you are printing on black fabric or if you are printing light colors on top of dark colors and your inks aren't completely opaque what is often done is a base white layer is printed before the color.

So if you're using plastisol inks the answer is yes, you can. But you may need a base white layer first.

Answer 2

Yes and no.

If you start with a white shirt, the process is the same as paper. So you can just cut out the white and use just one ink.

If you start with a black shirt then you can use a base white color. Sometimes you can make 2 passes of the same white to have it more solid. This is normally the procedure for cmyk prints.

But aditionally the inks can be for example puffy inks.

In the case of the stop sign you could use a red ink on a white shirt and then use a puffy white ink on the top of that.

So you can play with the options. The final result depends on the type of ink used, and how much it covers the previous color.

But try to avoid stalking to much layers of ink.