Overlaminates protect material from UV rays, weather, fingerprints, grease, dirt, and graffiti. They can also ensure that items stay smooth and flat, reduce glare from a light source, and change textural appearance. There are specialized types of overlaminates for various functions.
Uses of overlaminates include protecting flexible media, presentations and displays for businesses and in court, architectural renderings, mouse pads, banners, place mats, blueprints, photographs, posters, prints, certificates, and maps. They are also good for preserving small items such as labels, recipe cards, bookmarks, and wallet cards such as social security cards or library cards. Outdoor uses of overlaminates include protecting vehicle graphics, safety markings, and decals, as well as traffic and safety signage and other exterior signage.
Overlaminates fall into three main categories: cold or pressure-sensitive films, thermal or heat-activated films, and liquid. Pressure-sensitive films can be applied at room temperature. Low temperature heat-activated films are best applied at 185-210°F (85–99°C). The high temperature range runs from about 210-275°F (99–135°C).
The machines used for lamination may only apply the film to the item and press it into place, ensuring 100 percent contact between the item and the overlaminate, or provide heat to activate the process as well. The main types are the pouch laminator, so-called because the item is slid into a pre-made film pouch, and the roll laminator. There are heated and cold, pressure-sensitive versions of both types.
Overlaminates have finishes similar to those of latex paint, with choices like textured, luster, matte, satin, and glossy. There are canvas textured overlaminates that – when adhered to a print – make the image appear to have been rendered on canvas. Other special texture overlaminates offer a range of options for altering the appearance of portraits and prints in artistic ways.
Manufacturer’s descriptions enumerate the thickness, temperature, and UV ratings of overlaminates, and whether they are appropriate for indoor or outdoor use, or both. Some stand up well under direct lighting and are made to reduce surface glare, and this is also noted on the label, as is the method required for applying them. These guidelines are helpful in making a good choice for a particular project.