In food and beverage retailing, a self-adhesive label can create a multi-functional solution that will both simplify accurate workflow and product throughput and provide an invaluable additional level of product authentication. In the light of much of the media coverage of adulteration or falsification of products – baby milk, beverages and foods – the responsible brand owner today can choose to use one simple path to success, across all his required functionalities: a self-adhesive label.
Across all the end-use market segments, self-adhesive labels have established an unmatched reputation for reliability, coupled with versatility, in every respect. They are a preferred choice because of the extremely stable nature of the self-adhesive 'sandwich' – a laminate of printable face stock, adhesive, and the release liner which carries it along the press. Delivered in long or short reels, on their backing liner, the labels are ready for accurate, legible personalisation by any of today's variable information printing technologies to deliver a unique identifier.
Self-adhesive labels are an important addition to beverage packaging, sales and transportation, says FINAT's Jules Lejeune
These are functional labels which must perform in a variety of environments to meet different needs. They undertake a variety of important roles. They identify single items at the retail point of sale, in catchweigh applications, particularly for fresh foods. Here, the labels' dual readability role – correctly identifying the contents for the consumer and enabling the sales assistant to successfully scan the item's barcode – is critical. They can also perform a major function in product authentication and tamper-evidence.
The actual substrate to which they will be applied may vary from wood to rough card, plastic (films or containers), glass, or waxed cartonboard. It may be hot, damp, cool, or out of the freezer. Self-adhesive labels offer a choice of adhesives delivering reliable adhesion, whatever the circumstances. Certified adhesives for direct food contact (meeting FDA and BfR standards) are available.
But that is only part of the story. The label's face stock – its printable surface – must be able to conform to the pack to which it is applied. On flat surfaces, this is no challenge, but the situation is very different when it comes to curved packaging or 'difficult' surfaces such as apolar plastics which repel standard adhesives, or, for example, the roundels applied directly to self-serve fruits in the supermarket. Storage conditions – wet, damp, blast freeze, in particular – will also affect face stock choice.
Additionally, clear readability is essential (either by the naked eye, or with scanners). The imaging methods used for such labels also, therefore, make demands on the choice of label face stock. With self-adhesive labels, the ability to choose a preferred or special-purpose face stock and combine it with a preferred adhesive, and a release liner ideally suited to the label application method employed is a considerable benefit.
Self-adhesive labels, which may be pre-printed or not, can employ all the types of variable information print available today: the direct thermal, thermal transfer, ink-jet (including flat-bed), and laser print processes. The simple one-dimensional barcode has been joined today by two-dimensional barcodes and, based on the 2D technology, even three-dimensional barcodes.
It is the mature direct thermal technology, which creates images using heat on a heat-sensitive substrate, that primarily serves the retail market, particularly for catchweigh food labelling. It offers ease and reliability of use for short-life applications, and delivers relatively low-cost quality barcodes at reasonable print speeds. These characteristics also make direct thermal an obvious choice for transit product identification and tracking labels, for example for parcel distribution, as well as for outer case and pallet markings.
It is worth noting that, traditionally, Bisphenol-A (BPA) has been used in thermal papers as the standard image developer – but current concerns around its possible toxicity have led the manufacturers of self-adhesive thermal labelstocks to offer non-BPA alternatives for sensitive applications.
Thermal transfer, using ink ribbons with a thermal print-head, is one of the most flexible variable information print technologies, due to the variety of ribbons and printable receiver label materials (many UL approved) available, and its ability to print in colour. It is primarily used in industrial applications. Ink-jet print is now making inroads in the functional label market – with sell-by dates and other identifiers often added during the reel-to-reel printing of primary product labels for packaged foods on modular presses, which can include a digital print unit.
All in all, the self-adhesive label offers an unmatched flexibility and versatility in both straightforward day-to-day catchweigh labelling, and in advanced arenas such as 'smart' RFID labels and track-and-trace and tamper-evidence.