Evaluating the drying performance of UV and hybrid ink systems has always proved to be a challenge for printers. In response to this problem, PIA/GATF has developed of a new process controls product, thePIA/GATF Thumb Twist Test Form—a relatively simple multi-step test to perform.

This form includes several elements that allow for the evaluation of curing, image quality, and gloss characteristics. It has been designed in three zones to help understand the curing capabilities of the press. Each zone is made up of single four-color screens as well as overprints varying in coverage, from light to heavy.

How to Use the Form: Print the test form on a sheetfed UV/hybrid printing press, pull a sheet, place your thumb on any number of squares varying in coverage, and twist. If ink or coating appears on your thumb, the sheet is not cured.

The PIA/GATF Thumb Twist Test Form is supplied on a CD-ROM in PDF format. The PDF has been prepared for output on any image-setter or plate-setter. This form is designed for as four-color process image intended to evaluate multiple-unit printing presses. It can also be used on presses that have more than four units.