Screen Printing
Screen printing is a printing technique that uses a woven mesh to support an ink-blocking stencil. The attached stencil forms open areas of mesh that transfer ink as a sharp-edged image onto a substrate. A roller or squeegee is moved across the screen stencil, forcing or pumping ink past the threads of the woven mesh in the open areas.
Screen printing is also a stencil method of print making in which a design is imposed on a screen of silk or other fine mesh, with blank areas coated with an impermeable substance, and ink is forced through the mesh onto the printing surface. It is also known as silk screening or serigraphy.
Screen printing is arguably the most versatile of all printing processes. The advantage of screen printing over other print processes is that the press can print on substrates of any shape, thickness and size. The substrate or surface on which screen printing can be carried out are too many to be named. The CD covers you see are all screen printed. Beautiful cotton fabrics, silk and polyesters can all be screen printed on. Posters, signs, flyers, advertisements on buses, t-shirts and even watch dials are screen printed. Thus there are many applications of screen printing.

A significant characteristic of screen printing is that a greater thickness of the ink can be applied to the substrate than is possible with other printing techniques. This allows for some very interesting effects that are not possible using other printing methods. Because of the simplicity of the application process, a wider range of inks and dyes are available for use in screen printing than for use in any other printing process.
Utilization of screen printing presses has begun to increase because production rates have improved. This has been a result of the development of the automated and rotary screen printing press, improved dryers, and UV curable ink. The major chemicals used include screen emulsions, inks, and solvents, surfactants, caustics and oxidizers used in screen reclamation. The inks used vary dramatically in their formulations.