Silk Screen Printing Technology

Screen-printed wallpaper

Silk-screen printing, also known as screen printing and serigraphy, is a technology developed first in China during the first century of the Christian era. An Englishman, Samuel Simon, later patented the method in 1907. Silk-screen printing uses a silk mesh and a stencil. The stencil blocks ink from being transferred to the substrate and forces ink through the areas unblocked by the stencil. The basic method became popular for manufacturing wallpaper and fabrics and is still used for these applications today.

The Process

Old stencil press

The screen is placed on top of the substrate, which could be paper, metal, textiles, glass and other material. A stencil is placed on top of the screen, and the operator rolls a fill bar, or "floodbar," from the rear ink reservoir to the top of the substrate with an even pressure that floods the screen with ink. The ink is pressed on to the substrate and blocked by the stencil where ink is not desired.

The Screen

The screen

The screen is made of a fine mesh material, which was originally silk. Finer meshes will deliver a "higher resolution" on the substrate. Today screens are typically made of polyester, nylon or other man-made fibers, and stretched on aluminum or wood frames. Screens can typically be cleaned and reused after printing.

Stencils and Film

Film

In the old days, stencils were cut by hand. Today, stencils are made using photographic films that are designed for screen printing. This allows stencils to be produced from photographs and other artworks. It also allows screen printing to be used for a variety of new applications, like T-shirt designs, as well as improving the complexity and quality for traditional applications like wallpaper.

Screen-Printing Equipment

Screen-printing presses come in manual, semi-automatic and fully automatic. Flatbed and clam-shell designs are mostly manual and semi automatic systems. They are used for short editions, T-shirts and other fabrics. Rotary and cylindrical presses are fully automatic production machines used for manufacturing everything from plastic cups to soda cans to wallpaper.

Accessory Equipment

UV dryers

Depending on the application, there are a variety of accessory devices that may be necessary. If you plan to print in multiple colors, you may need a curing device to speed up the setting of the ink. Curing devices are usually infrared or ultraviolet light devices, but heat treatments are also available. There are also loaders, unloaders and other finishers that may be required depending on the work flow.

Applications

T-shirts

Screen-printing is used in different size businesses for production of different products. Mars uses it to imprint the "M" on M&Ms with soy-based edible ink. Most wallpaper fabric and many beer and soda cans are printed using screen printing, as are most T-shirts and many decals and labels. There are fairly low barriers to entry for small operations, and expensive, custom-made technology available for high production requirements.

References

• Artelino: Silkscreen Printing