Single-sided lamination has a variety of applications, ranging from book covers and posters to photographic prints and maps. While many people think that single-sided lamination can be achieved by simply loading only one roll of film onto a standard, two-sided laminator, the fact is that one-sided lamination is a unique process that requires specially-designed film and equipment. In this post, we take a closer look at single-sided lamination to learn what separates it from double-sided thermal lamination.
When you use a laminator for two-sided lamination, each of the sides is applying tension to the laminated document. Since the two sides apply tension in opposing directions, your document will lay flat. Because documents laminated on only one side aren't able to rely on the opposing tensions in order to keep the document from curling, specialized laminating film must be used in conjunction with a single-sided laminator in order to counteract the curl. Single-sided laminating machines feature decurling bars (also called "anti-curling bars"), which the laminated documents feed through before they exit the machine. These bars help to flatten out any minor curls that occur during lamination, and are found exclusively on single-sided laminating machines.
Nylon "Lay-Flat" Laminating Film
Also called "lay-flat" laminating film, nylon laminating film is specifically designed for single-sided applications. The adhesive used on lay-flat laminating film has a lower melting temperature than the adhesive used on standard laminating film (210-230 degrees F compared to 290 degrees F), which helps to reduce curling. Nylon also shrinks less during cooling than polyester, which is yet another feature designed to reduce curls in your laminated documents. Nylon laminating film is water-, oil-, acid-, and alkali-resistant, can be foil-stamped, printed, or glued, and can even be die cut. It is most commonly sold in a 1.2 mil thickness and on a 3" core, with widths varying between 12.5" and 19.5".
Problems with Using Your Two-Sided Laminator for Single-Sided Lamination
Aside from the curling issues mentioned earlier in this post, there are a number of problems that can occur when a two-sided laminator is used for single-sided lamination. If you load only one roll of film onto your laminator, any excess film that extends past the width of your document will leave adhesive residue behind on the other roller (which can even cause the film to wrap around the roller entirely - a messy and time-consuming clean-up). When you have film loaded onto both sides, the film on the bottom protects the bottom roller from the excess film on the top roller, and vice versa. Furthermore, nylon laminating film is sold on a 3" core, while most non-commercial laminators use 1" core film. As a result, most double-sided thermal laminators aren't capable of using the lay-flat film required for single-sided lamination.
Single-sided lamination is popular in a number of industries, because it protects one side of a document while leaving the other side bare for additional processes (such as book-binding or mounting). Contrary to popular belief, single-sided lamination is actually a distinct and separate process from two-sided lamination, and requires the use of specialized nylon laminating film and a single-sided laminator. If you have a need to perform single-sided lamination on a regular basis, then investing in the proper equipment and supplies is a must, because using a double-sided laminator will not give you the results that you are looking for (and can ultimately cause damage to your machine).