screen printing

Important Factors that Determine a Screen’s Longevity

Joe Clarke has spent the past 47 years in the lab and in the engineering department, in pre-press and on-press, as an R&D / technical researcher and as a manager of screen print production. Clarke has held executive positions as President of M&R Printing Equipment and as Vice-President at Wilflex [Poly One]. He has been granted a growing number of print-related patents, including one for High-Shear printing with Smilin'Jack - he is a member of the ASDPT, is an Associate Editor for NBM and an SGIA Fellow.

Clarke has presented hundreds of technical papers, written a couple books and published over 600 technical / management articles for which he has been awarded five Swormstedts; the international standard for excellence in technical writing.

Currently Joe Clarke is the President of CPR, a Chicago-based corporation which manufactures Synergy Inks including NexGen; environmentally & financially responsible T-Shirt inks. For more information on CPR, visit http://www.cprknowsjack.com/.

When choosing screens for your shop, one of the biggest factors to consider is durability, as it will determine the screen’s overall longevity. Don’t forget the cost of the screen in the screen room is pennies compared to the downtime cost a screen-pop causes on press. There are four main points which govern the longevity of the mesh as manufactured: the modulus of the yarn, the diameter of the yarn, the number of yarns per linear measure, and the fabric thickness.

The modulus of the thread is its stress and strain, also known as elongation over tension. Higher-modulus yarns require less elongation to develop a given tension level, and these yarns tend to hold tension longer. At a given modulus, the thicker the yarn the greater its strength, and the greater the number of yarns per linear inch, the stronger the fabric.

In the traditional 305-range of meshes, the fabric thickness runs about 1.60 times the thread diameter. The newer meshes range closer to 1.45 times the thread, which makes for a stronger fabric since the threads are less likely to shift the opening out of shape. This generation of fabrics allows the traditional weakling to be stronger than the ones that print poorly.