The Ups and Downs of Using Overlaminates

Overlaminates are becoming more and more widely used to protect images printed on a variety of substrates. Among those overlaminates are architectural finishes that add new life to signs and graphics that once had to stand on their own. Contrary to popular belief, overlaminates can be used on more products than ever, in new ways that one would not consider even a few short years ago. However, there are many PSPs that must learn to adapt the work to accommodate the use of overlaminates, particularly if a graphic requires a great deal of ink. High ink coverage can pose issues with overlaminates if the ink is solvent-based as it can cause delamination and other issues with the materials.

Jeff Stadelman, technical marketing manager of MACtac Graphic Products says that PSPs must be aware of how a piece is dried before lamination to prevent various issues.

"You don't change the way you laminate them but you certainly change the way you dry them. If the inks are dried properly lamination doesn't make a big difference," said Stadelman. "They start oversaturating it [the printed piece] and a lot of negative things can happen."

Paul Roba Technical Manager, Avery Dennison North America for the Graphics and Reflective Solutions division, said, "High ink coverage has to be under the limits as described by the manufacturer which typically is a 240 to 260 percent ink limit."

Roba goes on to say that the solvent in the ink can also cause the delamination of the product.

How does a PSP prepare a printed piece with high ink coverage for lamination? The answer is allowing for ample drying time.

Rick Nerenhausen, director of training, Lexjet states that the amount of ink should not affect the way a product is laminated if the process is handled correctly.

"If a print material is properly profiled, high ink coverage shouldn't change how you produce laminated graphics," said Nerenhausen. "Wait 24 hours for the print to dry before you laminate, and then 24 hours to trim a pressure-sensitive laminate to let the adhesive cure for a solid bond. You can trim a thermal laminate once it cools off, which is usually just a few minutes after you laminate.

Manufacturers of overlaminates echo Nerenhausen's opinion. If laminating products with high levels of ink coverage, the key is to allow ample drying time before applying the laminate.

Roba said, "If you do get up to those higher levels you really have to ensure that you allow the graphics to basically cure for 24 hours by loosening the roll on end and allowing some air circulation. It's all about the evacuation of the solvent from the media. If you don't evacuate the solvent efficiently what happens is the solvent will soften the vinyl; it will migrate through to the adhesive and cause the adhesive to become overly aggressive or in some instances it can cause the adhesive to fail prematurely."

Stedelman adds, "Make sure they have adequate dry time which is 48 hours, open to the air so all that solvent gets out of there before they laminate or they are going to have a failed graphic."

Judy Bellah of Clear Focus Imaging said, "One of the most common issues we see is not allowing enough time for the inks to dry thoroughly and outgas before applying the overlaminate to the print. Graphics printed with high ink coverage using solvent-based inks, e.g., may require extra time to ensure adequate drying and outgassing."

Exploring UV Protection

One of the benefits of using an overlaminate is to provide UV protection to the finished product. However, there seems to be some discrepancy between manufacturers and end users as to what UV protection really means.

Paul Roba said, "UV protection is the ability of a laminate to absorb some of the negative spectral output caused by the sun's UV rays. Just as you get damage to your skin you get damage to your graphics and premature fading to your pigment in your inks."

"Many laminates will have UV absorbers which will dissipate those – that harmful exposure of those UV rays. Some people mistakenly call them UV inhibitors but a UV inhibitor is typically an opaque pigment that will reflect back the light as opposed to something that's clear and will dissipate those harmful UV rays. Laminates do not have UV inhibitors they have UV absorbers."

"UV inhibitors in laminates provide some additional protection from the degrading effects of light and sun, but not substantial protection; they act more like a sunscreen than a sun block," said Nerenhausen. "The real value of lamination is that it provides rigidity, scratch resistance, a textured surface, and protection from ozone and other pollutants."

Stadelman said, "To many manufacturers it's adding materials to the films to make them last longer outdoors. To MACTac, it's a little bit different. We don't just make the films last a long time outdoors, we add a lot of other UV products to our formulas – whether it's to the film or to the adhesive that's there to also protect the image, to protect the ink. We've got UV filters or absorbers built in to protect the ink itself."

Matching Materials to the Job

With the wide variety of substrates available, it may not always be easy to choose the correct materials for the job. This can create a number of problems including delamination, failure of the adhesive, and irreparable damage to the final product. Experts claim that the best way to ensure the proper matching of materials to substrates comes through knowledge of the product including the end use plus a strong relationship to the client as well as the vendor.

Stadelman said, "Everything gets an enormous amount of R&D before we ever release it to the market. Typically, a rule of thumb is to try to match media to laminate film. So vinyl goes with vinyl, polyester goes with polyester, etc. I know that's not always possible. For 80 percent of the applications out there, that is the right way to go. Sometimes though you need to put polycarbonate to vinyl. When we design our adhesives and our films we make sure that we not only have the right face stock but also an adhesive that helps maintain the same coefficient of expansion and contraction and shrinkage if possible, so that one doesn't shrink more than the other. Our adhesives are designed to help the media not change dimensionally to not create failure in the field."

Tony Caruso, Eastern Region Sales Manager of Advanced Greig Laminators Inc. said, "Having a lam that matches the media is important. You can add lam to ink to increase the level of moisture proof you still need lam to protect the image."

"When people think of laminate, they think of plastic but laminate comes in a variety of materials—hot and cold. Having the right lam is vital to the application. It's important to try to match the laminate with the media."

Caruso goes on to say that AGL is different from its competitors because it uses a different system and way of matching overlaminates to various materials. "We have a match component system that allows us to match the quality of media and laminate. Low melt for the inkjet market, high melt for the offset market. We also add the match component system to our packaging. Our charts show media and description and then match it to the corresponding material."

Bellah said, "Different overlaminates offer varying degrees of optical clarity, conformability, UV protection, chemical resistance and durability, so matching the material to the job is essential. Both of our overlaminates have a clear pressure-sensitive adhesive and are applied without heat, are optically clear, and are designed to perform well with our perforated window graphics films. They have important differences, however."

For example, Clear Focus offers two main products that have specific uses and criteria. ClearLam is a 1.5-mil polyester film designed for use on flat surfaces only—e.g., retail store window graphics. It offers UV protection, and mark/scuff resistance. CurvaLam is a 2-mil cast PVC film made of high-quality, 100 percent polymeric face stock. CurvaLam mates well with our perforated window films, which are also made of PVC. More conformable than ClearLam which allows it to be used on items that have moderate curves.

When it comes to developing a relationship with a vendor, Caruso states the importance of working with someone with knowledge of the products and processes. Unlike catalog companies, AGL is able to offer expert advice.

Caruso says, "This is where AGL stands out. We are not a catalog. We're much more hands on as a company. It's where we excel."

Caruso continues, "There are many systems out there. They are so diverse. It's not about just choosing colors, profiles, etc. Now it's about understanding the process.

Pricing Overlaminates

Pricing overlaminates poses the same problem for PSPs as pricing any other finishing job. It is even more difficult if the PSP is not accustomed to using overlaminates or is somewhat uneducated regarding the process. Clearly, pricing is an important part of any job and a PSP has a large number of factors to consider before creating that final invoice.

Nerenhausen says, "Pricing is tricky, because it's very dependent on the local market and what that market will bear, as well as your business model and whether it's more custom or more production oriented. Still, some basic concepts hold true. Calculate all the items you use to get the job done—ink, material, time, overhead and anything else that goes into production. With that as a baseline you can determine what profit margin you can add to fit your market and the value of your product. The profit margin for someone mass-producing billboards will be quite different than a custom, color-critical print shop, and pricing will vary considerably coast to coast."

Roba also points out that the PSP must be aware of their own processes. "They just have to take into account what are the limitations and capabilities that they have. And then they have to take into account the time that goes in for set up, the time it takes to actually run the job, scrap, and then additional finishing of that and how long it's going to take based on the size... It's taking into account all of the variables and factors you have in your printing process."

Roba goes on to mention that PSPs must also consider amortization on equipment, overhead, and other factors that should go into the pricing of any job.

Caruso claims that pricing can be difficult for some because of the cost of materials which is not a fixed price. PSPs must also ensure that they are buying the right materials, not just focusing on cost.

"The market is very, very regionalized and there are price fluctuations like crazy so it's hard to put numbers down," stated Caruso. "It's important to find the right company to partner with. Buying the right tool for the right job is paramount to the process."

"Finishing should be viewed as an essential value added service. It's something that gives you a leg up against your competitors," said Stadelman. "Laminating and finishing should be a value add, it should be an upsell for them. It should be a way for them to add to their bottom line for a quality product. Again, it's how they separate themselves from their competitors."

Stadelman adds: "Pick the right product for the job and price it that way. You get what you pay for. It goes along that way."

Trends

As with any material or service, there are noticeable trends in the industry. Roba pointed out the ups and downs in trends and their uses:

"It seems with laminates it's kind of come to a plateau in that there are some specialty laminates but the drawback with laminates that create special effects are that the special effects are created over the entire graphic as opposed to localized special effects which most people would want. That's more of a limiting factor. So those I don't think have gotten the wide acceptance in the market as many people would have thought.

Roba continued: "There is a trend as far as laminates for paint replacement films. The laminate is actually incorporated into the manufacture of the film eliminating a step for labor and time at the converter and/or the applicator. It's not actually a lamination; it's an incorporation of the two products being fused together."

According to Stadelman, "Architectural finishes are really big right now. There's a lot of unique product, again it goes to that unique media thing, but also in the look of the finished product I think there's a lot of exciting laminate opportunities showing up on the market with more to come.