by clicking the arrows at the side of the page, or by using the toolbar.
by clicking anywhere on the page.
by dragging the page around when zoomed in.
by clicking anywhere on the page when zoomed in.
web sites or send emails by clicking on hyperlinks.
Email this page to a friend
Search this issue
Index - jump to page or section
Archive - view past issues
FLEXO Magazine : June 2012
Make every second count. It’s the ultimate in workflow acceleration, driving higher margins and slashing waste. Short run flexo now makes sense. It’s efficient. It’s profitable. Go to markandy.com/secondscount www.markandy.com Awarded for Technical Excellence Technologies & Techniques Maximizing The Anilox Perfect Process Control Refines Printibility By Jean Jackson Repeatability, productivity and consistency are all words we hear as flexographic printing continues to grow and compete. Every component and system of the flexographic print process has improved and evolved to better run to the numbers. Anilox rolls are no exception, as their purpose is to deliver a precise wet ink film thickness to the printing plate. HISTORY From early chrome and copper engravings with rubber roll systems and single blade systems, the anilox roll has gone through many improvements for better life, consistency and expanded capabilities. Mechanical engraved ceramic anilox rolls were introduced in 1969 for longer life and durability. The roll was mechanically engraved in copper or steel and then coated with a thin layer of ceramic coating. Rolls lasted longer but gave up some consistency when compared to mechanically engraved chrome rolls. This type of engraving is still used in some corrugated applications. In the late 1970s, with increased use of doctor blades, life of the mechanically engraved chrome anilox roll shortened and the density of ink decreased over the roll life, which could be as short as weeks. This led to a couple of innovators using lasers to engrave into a thicker ceramic and this began the current generation of ceramic anilox rolls. These engrav- ings lasted many times longer and over time developed the repeatability necessary to meet or exceed the chrome anilox roll. Many cite the laser engraved anilox roll’s development as a significant milestone in flexography ’s quality improvements. When used with the newer doctor blade chambers, there was an anilox roll that would last years and deliver a consistent, repeatable quantity of ink. The next three decades have seen the laser engraved anilox roll continue to develop. We’ve moved from early random engravings to uniform engraving patterns with a wide range of volume and screen count combinations, to finer screen counts and newer open structure engravings. This opened up the capabilities of optimizing the engravings for specific jobs and applications and helped expand flexo print capabilities. It also required and still necessitates better pressroom organization and communication. INVENTORY MANAGEMENT To maximize the benefits of these capabilities also requires better management, as rolls have an engraving pattern, cell volume and screen count. In the past, everyone spoke of the screen counts alone as the item that defined the print capabilities of the anilox roll; now, we need to reference the volume and screen count, along with patterns as newer open structures are being specified as they all influence the ink laydown, density and dot gain. An anilox inventory system and reference number system is an excellent process control tool to manage the range of engravings and the print process. Having an inventory list by press type with roll numbers can be helpful in duplicating re- sults along with following the anilox roll’s lifecycle. Knowing the MATERIAL MAINTENANCE • Every component and system of the flexographic print process has improved and evolved, but these systems must be monitored • Reference the volume and screen count along with patterns as newer open structures are being specified as they all influence the ink laydown, density and dot gain • FIRST 4.0 supplies several templates for anilox roll inventory management, press characterization run conditions data and press side specifications sheets • Anilox inventory system and reference number system is an excellent process control tool to manage the range of engravings and the print process • Getting an understanding of the ink metering system with the anilox roll, ink and blade suppliers involved will help the anilox roll be the precision tool it is designed to be 82 FLeXO June 2012 www.flexography.org