Choosing the right frame and mesh is critical to achieving quality prints. This overview looks at different frame types, mesh parameters and performance criteria, screen-preparation tips, and recommendations for ensuring long-lasting screens.
The screen-printing process derives its name from its key component—the screen. The screen consists of a strongly made wood or metal frame and a fine woven mesh stretched tight and securely glued or otherwise attached to the four sides of the frame.
A good frame has the following characteristics:
• slim enough to fit in the clamping device of the press system
• strong enough to withstand the pressures of the stretched fabric.
• constructed so water and cleaning do not affect it or interfere with the mesh tension or adhesion.
Originally, screen-printing meshes were made of silk, hence the name silk screen printing, and the Greek root for silk, seri, which gives us the European terms serigraphie, serigrafica, or serigraphy. In modern usage the screen meshes are made of precision woven polyester or, for some applications, metal.
Frames come in three main forms: rigid wood, rigid metal, or retensionable. Understanding the primary differences between these frame types will help you select the best on for your applications.
Wood The original and still the easiest and cheapest type of frame to make is wood. Wood frames are still used heavily in the garment industry, for hobby and art printing, for small jobs, and in non-critical large-format work. Early screen-printing with wood frames used staples or cord-in-groove for mounting hand-tensioned mesh. But hand stretching does not allow adequate or even mesh tensioning, and it is not recommended because of the problems slack screens create during coating, printing, and reclaiming.
Metal Thin profile aluminum or steel frames are superior to wood due to their resistance to warping or bowing, their resistance to water, their light weight, and longer usable service life. They are most commonly found in print operations with automated printing equipment or where quality printing is a requirement. Many are manufactured to fit common press sizes, or as custom creations to fit specific jobs or formats. Mesh is pre-stretched and glued to the frame using a special stretching device.
Retensionable A number manufacturers offer retensionable frames, sometimes referred to as roller frames (Figure 1). On these frames, mesh is attached using a locking strip and tightened on the frame itself using two wrenches. One wrench rotates the entire the side roller of the frame, and the other tightens a locking nut which holds the frame at the desired tension.
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