User login

Winding Up Productivity with Roll-to-Roll Screen-Printing Technology

(July 2008) posted on Thu Jul 03, 2008

Advanced digital control systems, improved engineering, and better material-handling technology characterize the latest generation of automated screen-printing systems for wide-format web substrates. Learn about the ease of operation, precision, and high throughput they can deliver in industrial and electronics printing environments.


By Reinhard Zimmermann

click an image below to view slideshow

The greater precision electronic controls also are key to enabling many specialty graphics companies to expand into electronics applications that have requirements for exact ink thicknesses and minimal screen stretch that non-automated presses cannot consistently achieve. Since membrane switches and other printed electronic products are a growing segment of the specialty graphics industry, we can expect that the capacity and sophistication of PLC-enabled control systems will become more and more a determining factor of where the industry can go.

More precisely, it is the software engineering that makes the real difference between one screen printing system and another. The best-in-class roll-to-roll systems use standard industrial components that one can source worldwide and customize the software for the precise application requirements of a particular specialty graphics company. These systems typically use higher capacity PLCs that are able to finely control all the inputs and outputs of a web printing line, including unwinding, web tension, material positioning, printing head position, web transport, drying systems, and rewinder.

 

Large-format considerations

In recent years, the growing demand for large-format work has required the use of custom-configured screen-printing systems to achieve maximum efficiency. In these applications, the generic 400-mm-wide flatbed systems are inefficient or just unworkable. Fortunately, along with improved controls, today’s roll-to-roll presses can be engineered to be virtually any size dimensionally. Flexibility is now the overriding design principle. Dimensions are custom-configured to job requirements, as opposed to putting the onus on screen printers to adapt to job formats feasible in the common 400-mm machines. Now roll-to-roll systems can be designed to support jobs as large as 2.3 x 4.2 m, which allows artwork layouts that provide higher yields and faster job throughput.

A change in physical dimensions that might not be as apparent is in the screen holder designs. These had been the same for as long as anyone can remember. Newer systems have redesigned screen holders to allow as little as 1 mm distance between the screen and the printing table. That means significantly less screen stretch, which is one of the reasons why roll-to-roll flatbed systems are playing a bigger role in high-precision electronics applications.


Terms:

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