Despite its important role in the screen-printing process, the squeegee often doesn
Profile Squeegee profile describes the shape of the squeegee blade. The most common profile in textile screen printing is a straight edge, although many other options are available, such as single bevel, double bevel, bull nose, and others (Figure 1). These other options are widely used in other forms of screen printing but are not commonly used in garment printing, with the exception of a few specialty applications. For textile-printing relevance, all squeegee references in the rest of the article will be focused on the traditional straight or square-edge squeegee profile.
Durometer is the measurement of the hardness of polyurethane squeegee material as measured on the Shore A scale. The higher the measurement of durometer the harder the squeegee is. Single-durometer blades consist of a single piece of urethane material at a specific hardness, generally in the 60A-90A durometer range. Dual-durometer blades consist of two layers of urethane of different durometer values, such as 50A/80A. Triple-durometer squeegees are a sandwich of three layers of urethane of different durometer levels, for example 75A/90A/75A. Each of these blade types is depicted in Figure 2.
The single-durometer squeegee is most commonly used in garment decorating. If you have ever purchased a new automatic press, chances are it was shipped with single-durometer squeegees. The main reason for the popularity of single-durometer squeegees is cost, which is typically much lower than for dual or triple durometer blades. This is very unfortunate because the benefits of using dual- or triple-durometer squeegees are many. This is not to say that single-durometer squeegee cannot be used effectively; they are just more difficult to use in terms of controlling deflection as pressure is applied dur-ing printing. Pressure on press can lead to squeegee rollover, which means that as the squeegee is printing it flexes so severely that it no longer shears the ink. Instead, it smashes ink through the mesh as the squeegee hydroplanes over the surface of the screen (Figure 3).
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