Full marks

Products and components need to be traceable after sale and, as Colin Carter explains, proper marking can reduce the potential for theft and counterfeiting

There are many reasons why marking of products and components is necessary. The ability to trace faulty products after sale is often a legal requirement (especially in the food and beverage and pharmaceutical industries) and proper marking can reduce the potential for theft and counterfeiting of goods.

One very crude but most effective method of marking many components is stamping — which is useful where items are to be subjected to harsh environments or where durability is required.

Norwood Marking Systems, for example, produces a special machine for the hot-stamp marking of wires for use in the aerospace industry, where insulated wire and cable can be marked and tested using an integrated spark tester — a big bonus when dealing with US aerospace industry regulations.

But marking isn’t necessarily the crude operation you may think. Pryor Marking Technology (in association with the Isle of Man-based Ronaldsway Aircraft Company) for example, has developed expertise in the aerospace field — notably marking technology for some of the components used in the Trent engines for the Airbus A380.

Components are marked with 2D Data Matrix information complying with internationally agreed formats that allow a database to identify specific information within the decoded data string, enabling true global traceability. Jet engine components, for example, are subject to extreme conditions and the most suitable form of marking was found to be precision-controlled dot peening, whereby a mark is made by indenting a solid carbide stylus into the material surface.

Data matrix coding is also a feature of Astra Zeneca’s drug carton packages for similar reasons — the company is using Domino Integrated Solutions Group’s experience in handling high-speed laser and inkjet variable data coding systems to label cartons as part of a worldwide traceability initiative.

Simon King, director of Domino’s Integrated Solutions Group, said: ‘Our flexible traceability systems are tailored to meet the recommendations by global regulatory bodies and are in line with European Federation of Pharmaceutical Industries and Association’s (EFPIA’s) recent recommendation concerning secure serialised code structures embedded in 2D data matrix code carriers for item-level coding.’ This is all aimed at protecting patients around the world.

Probably the most commonplace method of marking seen by the general public is good old-fashioned labelling — either attached by adhesive, tied on, stapled or even laminated under plastic. Enormous volumes of labels are used every day in the food industry for example. Next time you go to the supermarket just look at the number of items that have a sticky label showing the supermarket’s ‘use-by’ date.

One example is Marks and Spencer, whose sandwiches are labelled using a custom inkjet printing system developed by Linx Printing Technologies of Northampton.

The system required accurate and clear coding of real-time production information as well as fast ink drying and the ability for the labelling to remain legible and stay in place at low temperatures in chill cabinets. One innovation worthy of note here is the ability to detect when a sandwich box is not sealed properly — useful as no-one would enjoy food covered in ink.

In the same product area, UK wholesale sandwich company C&S Catering, which supplies hotels, restaurants, schools, colleges and universities, also uses labels for its sandwich sleeves and salad boxes. PrisymID supplies the company with two-colour printed labels with logos for its food range.

Printed sticky labels are not suitable for all foods, however — especially those not wrapped in plastic or paper to protect them. Foods such as hams are aesthetically spoiled by inks, as well as the fact that the choice of inks is limited by their being absorbed to some extent by the hams.

One solution chosen by Bearfields, producers of traditional hams, gammons and gammon steaks, is to apply a ‘lock-and-loop’ tag to every joint. These tags are supplied by Albion Systems and are made from a tough, tear-resistant material that accepts marking by traditional printing, thermal transfer printing and by good old-fashioned pen and pencil. The tags stay with the hams throughout the whole of the curing, slow-cooking and packaging production processes, and must be able to withstand temperatures up to 90ºC and be fully metal detectable.

Potential penalties from retailers have also driven cut flower supplier JZ Flowers to invest in rigorous labelling of its products to ensure bouquets delivered to its customers (including supermarkets Morrisons, Aldi and Netto) are accurate as close to 100 per cent of the time as possible.

JZ chose a barcode system developed by Label Store, incorporating Hand Held Products’ SV200 online verification solution with Datamax printers. The system ensures 100 per cent barcode accuracy and readability by checking factors such as contrast, symbol recognition, direction and reflection of light from the code. It can also detect missing or unreadable barcodes and take appropriate action.

Barcodes are also used to track electronic components and connectors destined for use in the automotive, medical and communications industries at Molex’s plants around the world. The company has installed Toshiba B-852 barcode printers to apply codes to every box and pallet — and with the company producing up to 4,000 products a day from some plants that adds up to a lot of labelling.

The system is controlled remotely over a network, and a label administrator can fix problems with printers in any of the plants.

Information such as part and order number, address of origin and weight are printed by the B-852s as TrueType font barcodes using direct thermal transfer. The information is invaluable for the company’s internal tracking as well as to meet shipping requirements.

Marking is one of those areas that is not always given the attention it deserves and in some form or other is a part of the majority of production processes somewhere along the line. And, as regulatory nets tighten around the globe, it is likely to become more important.