About Screen Printing
The process is often referred to as “silk screen” printing because the early screens used to be made up of silk strands. Modern screens are made of monofilament nylon strands – like very thin fishing line.
A screen used for printing typically measures about 18” x 24”. The customer’s image is transferred to the screens in darkrooms through a photochemical process -- one color at a time per screen. A 3-color job, for example, will require production of three screens. Some complex jobs require as many as ten screens!
What does a screen have to do with printing? Glad you asked. Whereas a regular printing press transfers ink from a metal roller to paper, a screen printing press transfers ink that is first squirted on top of the horizontal screen and then sqooshed by a squeegee through the tiny screen openings onto a garment stretched below it. (Now you know an industry insider technical secret: squeegees are for sqooshing.)
The shirt then rotates clockwise to the next position, where another color is sqooshed through another screen. If several colors are used, one position will be be reserved for a flash heater to dry the inks already applied. This prevents additional sqooshing from mushing the image. (We hope that you aren’t getting confused with all these technical terms.)
After the final color is sqooshed on the shirts, they are removed from the press by hand, examined, and then transferred one at a time to a giant conveyor belt heater to dry them completely. When they pop out the other end, the shirts are carefully inspected and then packaged for delivery.
Screen printing is fairly permanent, especially when premium inks are used. That’s all we specify at Cotton Images.com. It’s a far cry from the trashy and temporary iron-on process used by t-shirt shops. Those people know nothing about sqooshing and mushing
Price is affected by
- The quantity of garments ordered.
- The number of colors used, because each ink color requires the preparation of its own screen and frame.
- The nature of the colors relative to the garment color. Printing on a dark shirt may require extra work.