The Basic Process
Screen Printing uses a screen made of very fine polyester mesh. (Usually 100-300 threads per inch.) A stencil is chemically developed in the mesh, and ink is forced through the stencil onto the item.
- Art Prep:
High resolution art is prepared on a computer.
- Film Output:
Each color in the design is separated and output as a black image on its own special clear film called a Positive. (It's like a giant photography negative...but positive...)
- Burning the Screen:
Each positive film is attached to its own specially coated screen. When the pair is exposed to a powerful UV light, the chemical coating hardens in any areas not protected by the design on the film.
- Wash Out:
Rinsing the screen with water washes away any unexposed chemical leaving open areas that will let ink pass through.
- Press Setup:
Screens are clamped in the press and aligned, the stencil is checked for any problems (small holes, etc), edges are taped, and inks are prepared.
Ink is forced through the screen with a hard rubber squeegee.
- Textile inks are heated to over 320°F to cure the ink
- Poster inks are air dried
- Clean Up:
It's a messy process. There are things to clean afterward.