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Screen Printing Tip of the Week: Avoid Unwanted Images on Prints, Part 1

January 16, 2013

There are a variety of factors that can impact a print, resulting in an unwanted line, mark or ghost. Some of the more obvious, easy-to-check factors include:

Cleanliness:
The cleaner your workspace, the cleaner your print will be. For example, if there is too much lint on your pallet — especially if there are chunks with pallet adhesive from previous jobs — it can affect your prints. The uneven surface can cause dots or spaces not covered by ink to appear on your finished design.

Keeping your materials, including film, exposure glass/unit, pallets, workspace and tools, clean throughout the printing process can eliminate many of the factors contributing to unwanted images on prints.

Squeegee: Check your squeegees periodically to ensure there are no nicks on the blade. Even a small nick or deformity on your squeegee blade can cause lines on your print.

Emulsion: Use a good technique to cover the mesh uniformly and smoothly so that minimum or no touch-up is needed. If you do need to touch up a pinhole within your design area, be sure not to block it out using tape, which can leave an imprint on your design. Instead, patch up the pinhole using more emulsion and a brush.


Additional factors will be addressed in “Avoid Unwanted Images on Prints, Part 2.”



Kieth Stevens is the Western regional sales manager for International Coatings. He has been teaching screen printing for more than 10 years and is a regular contributor to International Coatings’ blogs. For more information, visit iccink.com and read the company’s blog at internationalcoatingsblog.com.