Wide-Format Laminators to Guard Your Graphics
If you don't already own a laminator, you might be missing out on opportunities to expand your capabilities and customer base. Here are some tips for first-time buyers.
It's tough to justify purchasing new equipment in an uncertain economy. But sometimes a device or technology comes along that offers you the opportunity to expand business, diversify your client base, keep more work in house, and generate products of higher quality. Enter the laminator, a tool that can accomplish all this and more--provided you can identify the right mix of machine features to meet your needs today and into the future.
The large variety of laminator models, sizes, and options can make machine selection a nightmare. To help you avoid confusion when shopping for a laminator, this article will walk through the features and functions you'll encounter on systems designed for graphics 36 in. and wider.
Why add laminating capabilities?
The notion that a laminator is only useful for image enhancement and protection sells the technology short. While using a laminator to add a protective overlaminate or encapsulate a graphic in barrier film will increase the durability and useful life of the print, the laminator serves a greater purpose.
"A laminator is not just a laminator--it's a print converter," says David Goetter, a consultant to laminator manufacturers and end users. "Laminators not only laminate, they mount, as well as bond, different types of polyesters or vinyls of different thickness to actual printed images."
To determine how a laminator might fit into your operation, you have to look at where your business is and where it's going. If you work with vehicle graphics or outdoor displays, a laminator will enable you to provide graphics with extra resistance to damage from the elements and fading caused by UV exposure. This extra protection is most beneficial for prints produced on aqueous inkjet printers, which have limited resistance to outdoor conditions. But even inkjet and screen-printed graphics produced with solvent-based or UV inks will see extra durability from overlaminating.
The same laminator you use to protect flexible vinyl- or paper-based graphics could also be used to mount prints to stiffer substrates, such as foam board. Besides keeping images secure and resistant to curling, rigid mounting can open up new opportunities in signage and P-O-P for your business. Some high-end thermal laminators will even function as high-speed transfer devices, allowing you to transfer thermal-resin and dye-sublimation prints from carrier materials to final substrates to produce banners and other fabric-based graphics.
Adding laminating capabilities keeps work in house and eliminates the time and expense of sending jobs out for lamination. According to Mike Hannon, president of LEDCO's graphic laminating business, the cost of jobbing out laminating is substantial compared to the cost of materials and equipment to perform lamination in house, especially because third-party laminating services often come with minimum order charges. Under such circumstances, a laminating job on a single print could end up costing you $100. "You're going to spend a lot more going out of house, and a lot of out-of-house guys tend to shy away from one-offs because they don't have any control over the media, inks, printing system, dry time, and all the other things you need to know when laminating," Hannon says.
The addition of laminating equipment also opens up opportunities to branch out into lucrative niche markets that rely on short-run product finishing. Dan Haan, general manager of Advanced Greig, says most end users are interested in putting prints through some finishing process, whether it's adding a textured overlaminate for a trade-show application or mounting a print to a rigid substrate for display in a courtroom. "Most of the industry isn't satisfied with just a paper poster," he says.
What type of laminator do you need?
Most laminators are so similar in purpose that choosing from many options and models can be tough. Your best bet is to start by considering laminator size. In general, it's best to buy the widest laminator you can afford. A wide laminator will allow you to run narrower products side by side (Figure 1), improve throughput, prevent film waste, and grow into larger, more demanding applications. If space is a concern, some wide-format models feature conservative footprints (Figure 2) and are ideal for tight production areas. Beyond size, familiarizing yourself with the main laminator components and methods of operation is a solid way to find the best unit for your business.
Cold vs. thermal Choosing between thermal and cold laminating units is an important decision. A thermal unit can process both cold laminates (those that adhere to the graphic substrate with a pressure-sensitive adhesive) and thermal laminates (those that feature a heat-activated adhesive), while a cold unit can only apply pressure-sensitive laminating materials. Prices for thermal laminators are typically much higher because of the heating systems and related controls used in those units.
Goetter's experience has been that most graphics shops will need to run both cold and thermal laminates over time. So he stresses, "Buy [a laminator] with a minimum of one heated top roller--even though heat is not required to process pressure-sensitive adhesives, a small amount of heat greatly benefits pressure-sensitives, especially if you are operating in a cold-weather climate." The reason for this, he explains, is because heated rollers can aid in flowing out the adhesives found in cold-laminating materials and accelerate the bonding process.
Construction Open architecture is a must, especially when it comes to larger laminators used in high-volume production environments (Figure 3). Operators need to be able to replace web rolls of la-minating film easily, but also must be able to readily access internal mechanisms, circuitry, and other parts. Chuck Thompson, vice president of marketing product development for the GBC Films Group, says sturdy casters and steel-shaft rollers that won't bend or bow are essential. Hannon adds that use of lightweight, rust-resistant materials (i.e., aluminum), sealed bearings, and color-coded wiring (for easy tracing) makes life easier on laminator owners and operators.
Haan explains that the combination of pneumatic brake and clutch found on some units gives users an effective means of controlling film tension. While he believes mechanical systems still offer the capability of maintaining successful process control, Haan says pneumatics allow the operators to dial in specific film tension levels prior to starting the process. "Improper film-tension control can cause delamination, print curl, or wrinkling," Haan says. "In the business of finishing, these problems will, in many cases, re-quire a rework of the product."
Rollers Rollers are a laminator's heart and soul. They're responsible for bringing the graphic material and laminate into contact with one another, so selecting the most effective type is essential for consistent, high-quality results.
Wide-format laminators, because of their size, are sometimes prone to problems in applying adequate pressure across the entire width of the products that pass through them. Some manufacturers have attempted to remedy this problem by installing crowned rollers, which are slightly wider in diameter in the middle than at the ends. But Goetter says crowned rollers are not an adequate solution. He explains that processing prints through crowned rollers can cause buckling or worse--a ruined print.
Haan agrees, explaining that crowned rollers make contact in the center of the rolls before making contact across the roll face. "You're going to be touching material harder in the center before you drive together the outsides of the material," he says. "That creates wrinkling or boat waking. Until a crowned nip roller is fully deflected, you'll get an uneven footprint at the nip point of the rollers."
Straight rollers are preferable because they facilitate uniform contact, even at very light nip pressures, according to Haan. He credits straight rollers with ensuring even throughput and predictable web handling of the film and media being laminated.
Many manufacturers will tell you that taking care of the nip rollers is a top priority because they come in direct contact with the products you're processing. You should be most concerned about surface flaws, adhesive buildup, or other blemishes on the rollers that could show up in the finished products.
Heat sources and cooling Most thermal laminators rely on a suspended heat source that runs through the nip rollers. The heater's duty cycle involves bringing itself up to operating temperature, heating the surrounding ambient air, and maintaining those temperatures. Contact heat sources are the most effective, according to Haan, because they are actually touching the inside surface of the roller assemblies. "The thermal recovery rate from the act of laminating is faster [with such systems], and they also provide the capability of managing temperature uniformity across the roll face," he says.
Maintaining an even temperature profile across the face of a roller is critical. Goetter explains that in less expensive roller constructions, where a single cal rod heating element is suspended in the center of the roller, the journals, bearings, and all of the steel used toward the end of the rollers act as a heat sink and draw heat out. "If you're processing film on a wide-format laminator, you may see variations as much as 20-30°F in the surface temperature of the roller toward the outside edges," he says. "This means you may have to raise the temperature above what is required for the thermal adhesive in order to get the temperature needed on the outside edges of the roller."
Thermal laminators generally feature a cooling apparatus between the pull rollers, which are responsible for maintaining proper film tension and guiding the laminating process and the laminating nip rollers. The cooling mechanism typically takes the form of chill rollers that pull excessive heat out of film and cool it to a flat state. The chill rollers are not internally cooled but rely on a fan bank or group of blowers to help them dissipate heat.
Controls and adjustability The materials with which a laminator may be compatible are largely determined by its adjustability. The main factors to consider are the range of temperatures, material feeding speeds, and material thicknesses supported by the unit and how these parameters are controlled.
In terms of controls, laminating equipment runs the gamut, from simple analog systems with mechanical switches to advanced, digitally driven systems with touchpad controls and digital readouts. Goetter says he's never been a big advocate of touchpads on machinery because they tend to have a more limited actuation life than mechanical controls. But Thompson sees touchpad-controlled digital systems as a benefit to operators because they can be used to program and store common job settings for easy recall. In the end, the type and number of jobs you plan to run will dictate the type of controller best suited to your needs.
Speed Throughput is always a concern in a graphics shop. It's easy to blame the laminator--the snail in the workflow trail. But Goetter says the bottleneck in production is actually the printer. He believes running laminators at slower speeds gives a higher guaranteed success rate of throughput and gives operators time to focus on more efficient ways to trim prints after they exit the laminator. Running a laminator too fast brings the risk of wrinkling, and high speeds will prevent proper bonding if too little pressure and heat are applied.
Bells and whistles Once you've determined what fundamental controls your system should have, you can begin to think about options and add-ons that might be useful. Holddowns, according to Goetter, are one option that can assist new users in feeding prints into the nip. But he cautions buyers that some machines feature those solutions because of inferior rollers. Haan says static-control devices are also practical because they help eliminate microparticulates that may be invisible to the human eye but become quite obvious once they're sandwiched between a graphic and overlaminating film.
Safety features Protecting operators is a top priority, especially when there's the possibility of burning, crushing, catching, grabbing, and other pitfalls. "Without question, no company should ever skimp on safety," Goetter says. Safety measures come in many flavors, including electric eyes, emergency stops, physical guards, and alarm circuits.
Physical hand guards are essential, according to Hannon, and "must be difficult to defeat, especially given the litigation climate today." He says a guard can actually aid the lamination process because some feature lay-down strips that help keep prints flat. Electronic eyes sound an alarm when an operator comes too close to the nip assembly. Emergency stops (e-stops) are also critical and should be easily accessible on all four sides of a laminator.
Training is, perhaps, the most abstract concept involved with buying and operating a laminator. For some users, an eight-hour course might suffice. But mastering the "art and craftsmanship of laminating," as Haan puts it, is an on- going learning curve. Goetter suggests a two-day training period that covers the overall process of loading and unloading films, explains how films differ from one another, and gives the new operator a chance to become comfortable with processing a print through the machine.
"Training should also include maintenance," Hannon says. "If you're down for two weeks, you're basically out of business on that line. And consistency of procedures is important. Learn how to do bond tests on different media--some things just won't bond."
If you think that laminating isn't something you can just jump into, you're right.
But with a clear idea of how you want to use a laminator and a little research into the available makes and models, you can soon be adding value and life to the graphics you print.
As a graphics provider, you owe it to yourself to check out the latest advances in laminating equipment. Who knows? A laminator may be the next winner you add to your finishing line.
Advanced Greig Laminators (AGL) 801 Burton Blvd. DeForest, WI 53532 608-846-1025 www.aglaminators.com
LEDCO Inc. 4265 N. Main St. Hemlock, NY 14466 800-345-5300 www.ledcoinc.com
Autobond Ltd. Heanor Gate Rd. Heanor, Derbyshire DE75 7RJ England 44 (0)1773-530520 www.autobondlaminating.com
Repro Technology, Inc. PO Box 357 Conroe, TX 77305-0357 800-835-8918 www.reprotechnology.com
Banner American Products, Inc. 42381 Rio Nedo Temecula, CA 92590 800-572-2144 www.banam.com
Seal Graphics Americas Corp. 7091 Troy Hill Dr. Elkridge, MD 21075 800-257-7325 www.sealbrands.com
Coda, Inc. 30 Industrial Ave. Mahwah, NJ 07430 201-825-7400 www.codamount.com
Venture Coating Technologies 1400 Venture Dr. Janesville, WI 53546 800-892-0273 www.expression-vct.com
General Binding Corporation (GBC) One GBC Plaza Northbrook, IL 60062-4195 847-272-3700 www.gbc.com
Wesco Machine, Inc. 1417 Commerce Dr. Stow, Ohio 44224-1791 330-688-6973 www.wesco-machine.com
InterLam Inc. 2053 Williams Pkwy. E., Unit 34 Brampton, ON L6S 5T4 Canada 905-791-2283 www.interlaminc.com
The following are comments about this article submitted by laminator manufacturer General Binding Corp. (GBC).
Dan Petersen, marketing communications manager GBC Industrial & Print Finishing Group
After reading your recent article entitled, "Wide-Format Laminators to Guard Your Graphics" by Ben Rosenfield, I wanted to point out a few discrepancies that our internal lamination specialists noticed.
First, it would be very difficult to make tension a preset value on a laminator. Variations in the manufacturing of the film, the film's diameter, environment, etc., can cause variations in the amount of tension applied to a film. This will never be a consistent variable where a customer can apply set amount of tension on a particular film.
Second, the statements made are misguiding with concerns to crowned rollers. Crowned rollers do not cause wrinkling or boat waking. Using too little or too much pressure causes these problems. Whether rollers are crowned or not these problems will still happen if the customer is not using to correct amount of downward pressure. For example, crowned roller do touch first in the middle, if I did not apply any pressure to flatten out the area between my rollers, my image would be pulled through the rollers more in the middle then the edges. Thus causing the aforementioned boat waking. But lets turn this around. If I have a set of flat rollers and I apply downward pressure on the rollers to achieve edge seal, I would deflect the rollers in the middle. This would cause the image to pull through the roller more on the edges then in the middle causing a D-wave in the image. Either way the rollers are manufactured, the goal is to achieve an even nip area while still being able to produce enough pressure to process PSA materials and achieve edge seal when encapsulating.
Third, is the heating source. It is true what Mr. Haan says about contact heat systems being more accurate and consistent. They are a coiled heating system. The journal is removed from one end of the roller. The coiled heater is inserted in and the journal is bolted back on. The drawbacks of this system are they are unserviceable. In order to replace a heater (which like a light bulb can burn out fairly easily), the entire roller would need to be removed, the journal would need to be unbolted (can be very difficult after being heated and cooled several times), and the heater pull out and replaced. Being that the rollers are the life blood of a laminator, I would not want to remove the roller from the machine for what should be a simple heater replacement. Like I said, admittedly this is a very accurate heating system many times within 5 degrees across the surface of the roller. Lamination does not require a heat tolerance to be that tight. Generally, being within 15 degrees is all that is needed. Our heaters are designed to provide accurate heat across the face of the roller, yet still provide serviceability to the system. The edges will see variations due to the loss of heat out the journals. If a heater is engineered properly, it is designed to compensate for this loss of heat.