HANDLE WITH CARE

Every package printer strives to produce packaging of the highest quality for its customers. Aiding in that effort is today’s higher anilox roll line counts. Line counts upwards of 1,000 have given printers the ability to reach realms of quality impossible with older, lower cell count aniloxes.

The only drawback to these higher counts is the delicate nature of the anilox cells, which can be easily damaged during cleaning. This is a conundrum printers need to consider and take seriously if they plan on reaping the full rewards attainable through these newer rolls.

“Higher count anilox rolls, in response to the need for higher quality printing, has raised the requirements for clean anilox rolls,” said Gary Wasch, regional sales manager, Doyle Systems. “These higher line count rolls are harder to clean and more fragile. Higher quality print requirements drive the need for consistently, thoroughly cleaned rolls.”

Michael Potter, president of Flexo Wash, agrees, “Just a few years ago there were numerous mediums or technologies that could adequately clean your anilox rolls of low line counts of 200 to 700. Today, flexo printers are changing the composition of their anilox roll inventory to include much higher line screen counts for process printing. Consequently, these higher line screen counts are creating new cleaning issues that printers have not dealt with in the past.”

There are several things printers can do to cut down on wear and tear to the anilox during the cleaning process. First and foremost is to act quickly. According to Tony Donato, technical sales solutions manager, HarperScientific, “The best way to keep the cleaning system from adding to the anilox wearing is for the operators to try to keep the ink from building up in layers, and from cross linking and fully curing. This is done when the roll is first taken out of service and/or is ready to be removed from the press and/or is at the end of the running of the roll. The old saying, ‘Never let the anilox roll dry’ is as good advice today as it was years ago. A little work up front can save a lot of anilox damage and wear, and save the printer budget.”

“Quick” and “economical” are the key words printers often cite when investigating new anilox roll cleaning technology. This makes sense considering the old adage, “Time is money.” It also validates the trend toward “more frequent cleaning because of higher standards on final product,” as pointed out by Jim Heffer of Anilox Roll Cleaning Systems.

Overall and more specifically, said Steve Paynter of Flexo Concepts, customers seek five things in their cleaning systems. “Customers are looking for a product that:

• Is effective in cleaning all types of materials from any line screen anilox. Some materials offer major challenges for most cleaning systems, so companies are searching for the perfect product that is able to handle all types of inks, adhesives, and two-component systems;

• Is safe for operators to use, thus protecting employees and the company from liabilities;

• Can not damage the anilox, either the surface engraving, or the base materials. Steel rolls can corrode under the ceramic and the inner materials of sleeves are easily damaged by chemicals and ultrasonic systems;

• Is ecologically friendly so that there is no cost or hazard for disposal of the cleaning materials. Also, companies are much more concerned about the VOCs they are emitting; and

• The cost per roll for cleaning is economical.”

While systems that fit Paynter’s list of customer-wants do exist and meet the demands of cleaning high count line aniloxes, it’d be a dream come true for printers if there was a self-cleaning roll. That dream is plausible.

According to Bobby Furr of Daetwyler, “Because of the capital investment involved, the fear of damage and harsh chemical additives, we believe that it conceivable that one day soon, there will be such a roll that will be self-cleaning or require minimal manual cleaning without the need for cleaning systems. Just like in wide-web flexo where automated wash-up systems already exist on the newer presses, many printers rely on this to clean their rolls without having to take them out and put them in a cleaning machine.”

That’s still a bit off in the future, but here are a few anilox roll cleaning systems available today:

Ultrasonic cleaning
Max Daetwyler Corp.’s Ultrasonic Cleaning System offers direct drive rotation, power depth adjustment, zone cleaning, and more efficient process control. The Direct Drive Rotation provides guaranteed constant rotation—no belts, chains, or slipping rollers. The Power Depth adjustment lowers the roller into the cleaning solution and automatically stops at the optimum distance for the most effective, uniform cleaning. The amplitude control allows for adjustment of the intensity of the ultrasonic power so that only the power needed to efficiently clean the surface of the roller is used.

To reduce ultrasonic exposure and extend the life of the immersibles transducers, the zone cleaning design of this system allows an operator to either turn down the power output to the already cleaned areas or to shut it off completely at these zones. This focused cleaning will extend the life of the roller and the ultrasonic equipment.—Max Daetwyler Corp.,
www.daetwyler.com

Alphasonic approach
Doyle Systems’ Alphasonic Engraved Roll Cleaners maintain print quality and coating weight consistency through thorough cleaning of engraved cells. These systems permit safe, frequent, and easy cleaning of two or more engraved ink or coating rollers. Features include dual frequencies, programmed temperature and timer controls, and frequency sweep for superior cleaning. Parts washers are also available.—Doyle Systems, www.doylesystems.com

Clean and protect aniloxes
FlexoConcepts’ MicroClean Anilox Roll Cleaning System cleans anilox rolls while safeguarding the anilox, the operator, and the environment. The MicroClean system is an off-press system which uses specially designed plastic pellets to gently remove dried ink from the anilox cells. This method is proven to do a thorough job of cleaning both ceramic and chrome rolls with line counts up to 1,200 repeatedly without cell damage. Unlike some other blast medias and cleaning solutions, the plastic pellets are non-abrasive and don’t damage the delicate cell walls of the anilox roll. The pellets are malleable and distort on impact, which renders them better at reaching the bottom of the cell and “picking” out the dried ink. The plastic media is not affected by humidity and is specially treated with antistat in the manufacturing process to prevent sticking. As an added bonus, it is recyclable; after cleaning a roll, the pellets are reclaimed for future use. This makes the MicroClean system the lowest per-roll cleaning cost of any on the market today.—Flexo Concepts,
www.flexoconcepts.com

FW anilox cleaning
Flexo Wash offers the FW Anilox Cleaners, fully automatic anilox roll cleaners designed to deep clean and restore anilox rolls or gravure cylinders of all sizes. The quick and gentle cleaning process leaves the anilox rolls totally clean and ready for immediate use after just 10-20 minutes of cleaning without causing any wear or tear to the roll. This makes it possible to keep anilox rolls totally clean at all times, ensuring a constant high print quality and a long life of the anilox rolls.

The different models and sizes offer various options but all have these common characteristics:

• The roll gets absolutely clean—no wear or tear on the roll—quick and easy to use; and

• The units can be designed for cleaning sleeves or plates. A complete range of sleeve adapters and plate drums are available.

In addition, the FW Anilox Cleaners work with environmentally-friendly, water-based cleaning liquid. The liquid is specially made for deep cleaning all types of ink. For sleeves, plates, and light metal rolls the appropriate liquid in a separate built-in tank is installed. The water from the high-pressure rinse is automatically led directly to the drain, to a tank for re-use, or to a water treatment unit. The water consumption is less than 1 gallon per each foot in length.—Flexo Wash, www.flexowashus.com

Non-hazardous formula
HarperScientific’s CeramClean II™ effectively and efficiently removes dried ink from the engraving without damaging the cell structure on ceramic and chrome cylinders. It removes water, UV and most solvent-based inks, and in most instances will remove those tough stains found on the roll face.

CeramClean II cleaner may be used on gravure and chrome cylinders providing the same results. Because of its powerful cleaning chemistry, CeramClean II provides quick, effective cleanups. CeramClean II is ready to use—no mixing required, is environmentally friendly thanks to its non-hazardous formula, and increases the life of anilox and coating rolls.—HarperScientific, www.harperscientific.com n