Tips and Tricks – Choosing the Best Pressure Sensitive Laminate for the Job
How to Choose the Right Overlaminating Film
For any printer – screen, digital or otherwise – it’s important to understand the available overlaminating films and when each should be used. In this post, we will focus on choosing the right pressure-sensitive overlaminate for your application.
1. First, consider the intended end-use of the graphic and determine the necessary durability and installation requirements. Public safety will also be a factor in some applications:
Durability: The durability of the graphic is directly related to the environment in which it is installed (i.e. indoor vs. outdoor; wall graphic or floor graphic; exposure to moisture/ lighting/ temperature/ traffic/ etc.). These conditions affect the durability of a film and ultimately the graphic. With this in mind, manufacturers create different qualities of films to help you maintain the proper balance of cost vs. function. For example, premium quality films that incorporate UV stabilizers, higher quality, longer lasting facestocks and technically engineered adhesive systems cost more.
Installation: All other factors lose their importance if the overlaminating film is not easy to use. Choosing the right film can make your job easier. For all graphics, thickness of the laminating film plays an important role in the conformability / rigidity ratio. The thicker the film, the more rigid it is, and the easier it is to work with when the graphic needs to lay flat and stay that way. The thinner the film, the more conformable the graphic will be against uneven or curved substrates.
Public Safety: Public safety should be everyone’s responsibility –including laminating film suppliers and printers. Consider if a fire were to break out – the graphic should not serve as extra fuel for the fire. Understand applicable national and regional building codes that apply to your application as it pertains to flame resistance standards for materials. This is particularly important in public areas, such as museums, bars, malls, etc.
2. Second, determine the best combination of the three main components of pressure-sensitive overlaminating films: adhesive, facestock and liner.
Adhesive: Finding the clearest, most uniform adhesive the budget can afford will greatly affect the aesthetics of the graphic; therefore the higher the profile of the graphic, the more important the clarity of the adhesive becomes. For instance, museums often leave displays in place for long periods of time and they want the display to be just as pleasing the last day as it was the first. They may select the clearest adhesive available. Suppliers often sell adhesive in “good,” “better,” and “best” packages that range in clarity, cleanliness, smoothness and UV protection.
Facestock: Different film facestocks provide varying levels of glossiness, so the application’s lighting should play a role in facestock selection. For example, a high-gloss film in a brightly lit room will cause glare –taking away from the graphic rather than adding to it. With floor graphics, choosing a finish with slip resistance qualities is extremely important for public safety. Examples of different overlaminating facestock materials include:
• Vinyl is the most common facestock for pressure sensitive overlaminating films because it is relatively inexpensive, has excellent layflat and conformability, and is durable. During manufacturing, it is also an easy process to change the gloss level, which further drives cost down. Common applications include: vehicle wraps/fleet marking, point-of-purchase displays and floor graphics.
• Polycarbonate is found in 5-, 10- and 15-mil thicknesses and used where stiffness and durability are the key variables in the finished graphic. Two main applications include: tradeshow graphics and floor graphics.
• Polyester is typically a more expensive overlaminate facestock. It provides the best clarity and is commonly used for high-end displays found in museums, airports, or anywhere premium graphic quality is essential. However, unlike its counterpart (vinyl), polyester tends to scratch easily and would not necessarily be recommended in places where it will be touched a lot or walked on.
• Polypropylene has a very specific quality, making it appealing as an overlaminate. It provides the graphic with a “dry-erase” surface and is often used on menu boards, calendars or courtroom graphics.
Liner: The liner is instrumental in the performance of the film during the finishing processes. The smoother the liner, the smoother the adhesive; the smoother the adhesive, the better wet-out (less silvering), resulting in a clearer, deeper finished graphic. Also, higher quality liners provide improved stability in the laminating process, resulting in more consistent and faster laminating speeds.
3. Finally, once the appropriate combination of adhesive, facestock and liner is determined, the thickness of the material will also need to be weighed, depending on your application. Thickness is measured by adding the components together. Ask your supplier for recommended thicknesses based on your application.
Applying This Knowledge
All of these variables can get a little confusing or overwhelming, so the right answer may not be immediately clear. The good news is that there are people out there who know the materials and processes so well that you can find some help with your graphic puzzle. Just ask. And keep in mind, even when using UV inks, laminating can provide added image enhancement, protection and durability not provided by the UV ink alone.