- Screen printing is a process using light-sensitive materials and film-positive images to print on paper, wood, plastic, fabric and many other materials. Once the image is on the screen, ink is pressed through the screen with a squeegee to create a print. Screen-printing ink is brilliant and creates a dynamic-looking print. It is possible to print multiple copies, and to use one color of ink or multiple colors of ink. A screen must be prepared for each ink color used.
- In order to screen-print an image, the image must be transferred to a film positive. The graphic may be prepared in a graphics program such as Adobe Illustrator or Photoshop. Simple graphics, such as typography, may be prepared in a word processing program such as Microsoft Word. Drawings may be scanned into a graphics program. The graphic may then be output onto a transparent sheet or piece of vellum using a laser printer or inkjet printer. It is recommended to use a laser printer for sufficient opacity of image to successfully burn a screen. There are specialty programs to convert inkjet printers for creating screen-printing film positives, but they are quite expensive.
- A screen is made of synthetic screen mesh stretched over a wood or metal frame. The printer coats the frame with a light-sensitive emulsion. When that's dry, the printer places the film-positive face down on the screen. A piece of glass is placed flush against the film positive. With light from an exposure lamp and a spray of warm water, an image appears on the screen. Once the screen is dry, it is clamped into a screen-printing press. The printer uses a squeegee to wipe ink through the screen mesh and onto the T-shirt.
