LED UV Systems for Sheetfed Offset Printing at Full Speeds
AMS LED systems bring high energy efficiency, heat-less solid state UV LED curing to sheetfed offset lithographic printers everywhere. Gone are powder-filled pressrooms, expensive IR/Hot Air dryers, marking problems and waiting for sheets to dry. No other system provides the high intensity, flexibility and fast return on investment ROI of AMS LED systems. With simple installations on nearly any type of press, AMS LED is helping customers reinvent their conventional sheetfed offset printing operations with stunning results and digital turnaround speed.
AMS LED UV systems print and perfect at top press speeds in sheetfed offset lithographic printing. The results are superior to H-UV and UV, and offer exceptional results for immediate post production steps such as cutting, scoring and fabrication.
It Begins with the World’s Most Powerful LED Curing Lamps – The XP3 and XP5 Series
The AMS XP3 (for medium speed presses) and XP5 (for high speed presses) Series LED UV Curing Lamps are what enable the breakaway results with UV LED printing and curing in sheetfed offset. A common system configuration consists of 1-2 LED lamps, typically mounted at the end of the press at an Interdeck location pre-coater, or in the Upsweep delivery location post-coater. Because the lamps are completely interchangeable, they allow total job flexibility without sacrificing printing options. Need to cure opaque white after unit two? Just add another LED module.
PEAK Optics Deliver Curing Intensity that Works in Sheetfed Offset Presses
In sheetfed offset machines, the challenge for LED UV curing is achieving high intensities at exceptional working distances. Most presses require a mechanical clearance of at least 30mm (1.25-in) in the inter-deck or inter-station area, and up to 100mm (4-in) in the delivery or upsweep area. Traditional UV LED systems designed for close range curing of ink jet are not designed with optics to overcome this challenge.
AMS solved this problem with its proprietary and patented PEAK Optics system, allowing a high intensity collimated beam of light to travel from the base of the lamp to targets up to 150 mm (6-in) away. Using PEAK Optics, a single XP Series LED UV lamp can cure at any position on the press with intensity exceeding 3x the most powerful mercury arc UV or H-UV lamp, at half the power consumption and with no unwanted side affects. The results are exceptional curing at the highest press speeds from any location.
AMS Has More LED UV Installations on Sheetfed Offset Presses than Any Other Manufacturer
AMS XP3 and XP5 Series curing lamps come in standard sizes to fit nearly any press in use: from Akiyama, Heidelberg, Komori and Sakurai – to KBA, manroland, Ryobi and Mitsubishi – all have all been converted. As an early developer of LED technology, AMS solved some of the technical limitations preventing more wide scale adoption of LED UV multiple types of sheetfed presses. And because there is no heat, no ozone ducting, and no moving parts, AMS LED UV lamps install very fast.
Today, AMS LED is on more sheetfed offset press types than any other system in the world. Because AMS LED modules are compact, seamless and manufacturable to any length, we can easily fit any curing width requirement, even if it’s not a standard one.
Compact, Modular, Programmable LED UV Control Units
The full benefits of LED printing, such as variable intensity dosing, segmented output, and programmable data communication with the machine are made possible with the AMS Light + Control (LC) LED UV Control System. Capable of driving lamps from the smallest sheet sizes to large formats, the LC Control Systems were designed for full programmable control of the LED lamps, maximum protection of the LED system, and a compact footprint for easy placement. Care to move the LED between two presses? The LC system may just be the most mobile curing system ever created.
Installation Example of LED UV at a Sheetfed Interdeck Position
On most sheetfed offset presses printing up to 6 colors, a single XP3 or XP5 LED module is installed prior to the turn on perfector machines, or prior to the coater or in the upsweep delivery on straight presses. The AMS XP modules are very easy to install, and move easily between multiple prepared positions on the press. AMS has standard models for most machines on the market, and works closely with the industry’s leading OEMs.
Installation Example of LED UV in the Upsweep Delivery Position of a Sheetfed Offset Press
For straight presses, or the second side of a perfector press, a single AMS LED UV module is typically located in the upsweep delivery following the coater. Not only are inks cured at top speeds with up to 300% coverage, but special LED OPV or C-LED coatings can be applied and cured for gloss, matte, strikethrough effect, spot or protection benefits.
LED in Sheetfed Offset Provides Instant Drying on Paper, Metalized Stocks, Synthetic Papers and Plastics
When printing with LED UV and polymer inks, no spray powder or heat is required to accelerate drying time on the press. Expensive and problematic cylinder jackets are not required when printing in perfecting mode, and drying problems are erradicated on nearly all stock types, including gloss and matte coated papers, uncoated offset papers, paperboard for packaging, non-porous synthetic papers, foil-laminated sheets, and plastics such as lenticular as well as most plastic packaging, card and label stocks.
Water-proof LED Inks and Varnishes Provide Higher Gloss, Color and Sharper Dots
With the polymer makeup of LED inks and varnishes and the low heat of the UV diodes, higher gloss levels can be achieved than with conventional UV or H-UV. Higher color fidelity and sharpness is achieved through trapping and flash curing the ink on the surface of the stock.
One of the most interesting benefits of LED offset printing is the nature of the ink itself. When an LED ink cures, it forms a polymer chain that not only protects the sheet, it is no longer water soluble, and it resists most solvents. In addition to LED inks, coatings and varnishes (OPV) can be used to flood or spot coat the sheets – either for graphic image enhancement, or to completely seal the sheet (for example, restaurant menus or book covers).
In conventional oil-based printing, most sheets are protected with water-based aqueous varnishes and coatings that liberally waste thousands of tons of water and energy. Because LED polymer inks are already dry and impervious to scuffing and marking, sheets no longer require a protective coating. If a coating is required for functional or graphic enhancement reasons, it can be added via LED lithographic OPV (overprint varnish) or LED flood coating via a coating tower. The LED approach to sheet protection not only preserves a dynamic look and feel of the image with incredible environmental savings, it promotes the benefits of the underlying paper.
LED UV Generates no Heat into the Press or into the Sheets
Because UV Light Emitting Diodes produce 100% of their spectral output in the UV range, they avoid the problem of heat generation common in H-UV, LE UV and standard mercury UV arc lamps, where infrared and convection heat and wasted spectra account for up to 80% of the lamp output.
The result with LED printing is lower pile temperatures, no curling of stocks, no registration issues with heat sensitive substrates and no loss of moisture in the paper for improved post-press throughput. And there is a further benefit… LED printed sheets do not smell of the noxious odors released from heat-activation of chemicals within substrates. Unlike any other means of drying, LED retains a true freshness to the printed material.
Unlike H-UV, UV, IR or Hot Air, the absence of heat also benefits the press. Gone are risks of fires, nuisance trips, and costly UV preparation of units. The resale value of the press is maintained at the highest level.
LED is Absolute Green-Tech and 100% Future Compliant
LED UV curing is rapidly gaining ground and for all the right reasons in printing. LED UV brings the UV curing benefits while eliminating all of the drawbacks and objections of conventional UV. Compared to UV, HUV, HR-UV or LE UV – all methods of curing that all rely on mercury lamps – LED removes the risk of Mercury or Ozone contamination and is 100% compliant with future bans on Mercury (Hg) for human safety.
LED UV provides instant ON/OFF activation of the lamp, which means there is no warm-up or cool-down cycle required with other forms of UV, and therefore no shutters required within the lamp housing that could stress or fail during repeated use. The result is not waiting time between press wash up cycles. LED is completely ready to print when you are.
In addition, the UV LED diodes within AMS XP systems provide up to 20,000 or more hours of constant, predictable energy output. Conventional UV lamps provide up to just 2,000 hours and they degrade from the moment they are put in production. H-UV, HR-UV and LE UV lamps are iron doped, and as a result degrade even faster at 650 hours per lamp. It is no wonder that LED’s are quickly becoming THE choice for high speed curing.
For a comparison of UV and other low energy curing methods, such as H-UV, LE UV and HR-UV, please refer to the following section of our website.