User login

Training for Reproducible Color

(December 2001) posted on Fri Jan 18, 2002

Today, promotional graphics demand process color. Can your screen-printing shop deliver?

click an image below to view slideshow

By Bruce Ridge

So are employees getting the kind of process-color training they need? Some new recruits may have had exposure to screen printing through a college or high school course. But few of these programs focus on the production of commercial graphic images, especially process-color ones. A few universities have \"graphic communication\" programs that teach screen printing along with the other printing processes, but again, the focus is likely to be limited.

For most printing shops, the most effective option is to use process-color training resources from within our industry. For example, the Screen Printing Technical Foundation offers regularly scheduled courses on various process-color printing functions. Unfortunately, concerns about expense and loss of manpower mean that few shops take advantage of this type of focused training.

The final training option I'd like to discuss involves programs established by industry suppliers. Some of these occur at the supplier's facility. Others, such as the program conducted by Nazdar in cooperation with other industry suppliers, are travelling programs that are presented at multiple locations around the country. The latter type allows us to reach far more printers than might otherwise seek training. During the past year, our travelling three-day process-color seminar was presented in 13 locations across the US and drew more than 400 attendees.

One benefit of conducting this program was is that it helped us form a picture about what printers know and don't know about process-color reproduction. Prior to the start of each seminar we surveyed the attendees to find out what their job positions were, what they hoped to learn, and what problems were occurring most frequently in their four-color printing. Surprisingly, we got very similar answers at each seminar location.

Based on these responses, three areas of process-color reproduction stand out as the greatest challenges for screen printers: 

Moiré moiré is a recurring and unpredictable problem for most shops printing halftones at 65 lines/in. or higher.

Dot piling and tonal shifting Dot piling occurs when halftone dots of UV ink are printed on nonabsorbent substrates. The dots create stacked formations that lead to dot gain and a host of other image defects.

Proofing Very few printers understand the proofing process, the proofing systems available, and how to specify a proof in order to predict a screen-printed result.


Did you enjoy this article? Click here to subscribe to the magazine.