The Bookman’s Glossary published by Publishers Weekly and Library Journal in 1961 gets straight to it: “The major commercial application (along with Mimeographing) of the stencil principle of printing. Silk screen printing is little used for halftones or for small type or for runs over 5,000. It is much used for posters and for printing on glass, plastics and textured surfaces. It utilizes the simplest of equipment: a piece of silk stretched on a frame and blocked out in the non-printing areas and a rubber squeegee* to push ink or paint through the porous areas of the design.” This picture, from Wikipedia, illustrates the system well.

A. Ink. B. Squeegee. C. Image. D. Photo-emulsion. E. Screen. F. Printed image.

Now the process tends to be referred to as screen printing, or in artistic parlance, serigraphy, a name devised in the 1930s by a group of artists using the technique who wanted to differentiate the artistic application from the industrial use of the process. Andy Warhol, not of course one of that group, is no doubt the most notorious artistic user of the technique.

The “silk” part of the name has pretty much been dropped by the industry, because modern screens are commonly made of artificial fibers, mainly polyester, nylon or even a steel mesh. While individual users will likely be printing from a flat screen, industrial applications in longer runs are likely to be printed on rotary presses. Fabric printing is perhaps the commonest such application. Electronic circuits may also be printed by screen printing machines. One advantage of the process is its ability to lay down a heavy layer of ink.

The earliest firm evidence for screen printing comes from China during the Song Dynasty (960–1279 AD), and the technique didn’t reach Europe till the late 18th century, according to Wikipedia. Handmade screen prints may have the blocking agent painted on by a brush. In commercial applications an emulsion is applied and is selectively exposed to ultra-violet light through a film printed with the required design. The exposed areas are hardened by the light, leaving the unexposed parts to be washed away using a water spray. The remaining uncoated area in the shape of the target image will allow the passage of ink.

Stencil printing is a conspicuous absence from my post Printing methods.


* I’m quite surprised to find that the earliest use of the odd-looking word “squeegee” dates, according to The Oxford English Dictionary, from 1844.