How to Expose Photo Emulsion for Silk Screen Printing. When you have a coated screen ready to go, use the best source of light to expose your screen - the sun!
Things You'll Need
- Coated Silk Screens
- Contact Exposure Units For Silk Screen
- Garden Hoses And Attachments And Water
- Little Red Wagons Or Dolly
- Art-prepared As Transparencies
Place the silkscreen frame - coated with emulsion that's dried - in the contact exposure unit. The well of the screen should have the foam inserted into it and be locked down in position, flat face up.
Place the artwork to be exposed (the transparency) on the emulsion surface "wrong reading" (i.e. backwards) in the center of the screen.
Place the plate glass over the art, sandwiching the art between the glass and the silkscreen mesh. Make sure there is contact over the entire surface of the art. (The emulsion is slow, so you can do this quickly under normal light.)
Use a dolly, a little red wagon, or two people to take the entire unit out into direct sunlight, being careful not to disturb the glass or move the art around in any way.
Let the contact unit sit in the direct sun for at least 20 minutes. (See exposure times below.)
Wheel the contact unit into a shady area (or indoors if there is an area set up for washing inside) after exposure.
Disassemble the unit, removing the art and glass from harm's way.
Place the screen in an upright position, braced in such a way so as not to move when sprayed with water.
Use a garden hose or power washer to spray the entire surface of the screen with water. At first, do this with low pressure from a distance. Within 2 minutes the screen will start to open up and the positive areas will start washing away.
Move closer if necessary, increasing the pressure of the hose and focusing it on any areas that do not seem to be washing away.
Continue until all the positive, unexposed places in the screen are washed clear.