I have been dabbling in screen-printing in a completely unofficial, self-taught way. Recently I was asked to do some bachelorette t-shirts and decided this would be a good opportunity to document the process. Here goes–this is going to be talking about the photo emulsion process.
First, there’s the design. You need to find a design, preferably one with not too much detail/too many teeny lines. It’s doable, it’s just a little more difficult to execute. Once you’ve come up with something, you need to print it on a transparency.
I read a tip somewhere to print it twice and tape them together to make the ink even darker–I highly recommend this. You don’t want any light to get through the design.
Once you have a design, you need to prep a screen with the photo emulsion. This can be a little difficult, because it needs to be done in a dark(ish), stored in the dark to dry, and then kept in the dark until you use it. There’s also a shelf life for the screen once you’ve put the emulsion on. I have to do this process on my closet floor–it’s the only dark room in the house, and the cats don’t have access.
After your emulsion is on and dried, you’re ready to burn the screen. There are tables to tell you about the wattage, what type of bulb, how far off from the screen, etc. For our purposes, I’ll just say there are very specific directions for this. If you don’t burn it long enough, your whole screen will wash out. Too long, and it’ll be difficult to wash the design out. My screen took about 45 minutes to burn with a lamp hanging 12″ above the screen. I put a clean sheet of glass over the design in order to make sure the transparency lies flat on the screen surface–you don’t want any light to get under the transparency.
Next is the washing process. Once the screen is finished, you “wash out” the design (everything that was untouched by light), while everything that was exposed to the light will stay put. A lot of sites will recommend a pressure washer or something of the sort to wash the screen out. While that would be fabulous, I live in an apartment. I have a sink and a tub. Neither of these things really have water pressure conducive to this step, so I resort to my trusty industrial squirt bottle. It’s tedious, and I get serious hand-cramps but I make it work.
The dark green is the burned photo emulsion. The pale green is what the burned design looks like, and the white is where I have washed the design out.
After about over an hour (no joke) of squirting and rinsing the screen (you can imagine my hand agony), the design was finally washed out. When the screen is dry, you can begin your printing.
Because the printing process needs to happen fast (so your paint doesn’t dry and clog the screen), I didn’t take any pictures. My personal process involves the ironing board, a piece of wood (to put in the shirt so the ink doesn’t bleed through to the back), and the helping hands of Brandon. Lay out shirt, place screen, paint, squeegee, remove screen, hang shirt, repeat. In this particular run, repeat 14 times. Voila! Printed shirts.
Screen printing is fun, messy, and time-consuming. It’s essentially a 3 day process (one day to set up the screen, one day to burn/wash out the screen, and one day to actually print). I am looking forward to taking some classes and getting more knowledgeable, but for now I’m experimenting and having fun!