Traditional Printing Techniques

Four printing techniques have prevailed in the printing industry as the techniques of choice: flexography, rotogravure, large-character ink-jet and laser printing. The innovative, “smart” technologies have been developed to work alongside these existing methods in order to add substantial benefits and take printing techniques to a new level.

Flexography

Flexography, which is also called surface printing and is often abbreviated to flexo, is able to reproduce highlight tonal values, thus providing a workaround for the very high dot gain associated with flexo print. Another major advantage of the technique is its ability to use a wide range of inks and print full-color, continuous patterns on many types of absorbent and non-absorbent materials. Due to their low viscosity, flexo inks enable faster drying and, as a result, faster production at a lower cost.

Although a fast and economical method, flexography can be associated with efficiency losses when it comes to changing the content of the printed text. When text or codes need updating during flexographic printing, users must change the printing plates and sometimes make new ones. This can be time-consuming, as it requires the production process to stop and be restarted. Considering the increasing number of languages and international symbols that need to be printed on packages and the strict regulations requiring packages to bear lot codes and expiration dates, the packaging industry must consider implementing new technologies in order to minimize the time and money loss associated with having to change printing plates.

Rotogravure

Rotogravure, or gravure, has also been used extensively by the printing industry; its main advantage compared to other printing processes being that it is capable of transferring more ink to the material to be printed. As a consequence, the technique has been noted for its remarkable density range from light to shadow as well as its ability to print a wide range of substrates such as polyethylene, polypropylene and polyester. However, with rotogravure, all images, including type and solids, are printed as dots.

Large-Character Ink-Jet

Large-character ink-jet printers are also a popular technique employed by the printing industry and have been preferred for being the fastest and least expensive units available on the market. Unfortunately, this technique requires maintenance and can be quite messy. In addition, the image produced by ink-jet printers may fade after successive use.

Laser Printing

Laser printing is another popular method. The latest, most-advanced laser marking systems use a high-powered beam to ‘ablate’ data onto the print material by ‘burning’ away a black ink patch to form white spaces, thus exposing the underlying substrate material. However, when using laser ablation, it is possible that the speed of the production line may create problems for image resolution levels. Additionally, laser printers can be subject to toner flaking, which may make them unreliable for long-term bar code printing.

Some of the limitations of conventional printing techniques have triggered research toward finding a method that would be capable of overcoming these shortcomings. Over recent years a number of “smart” technologies have been developed in order to achieve this. This new technique compliments the existing methods, offering increased productivity and product quality in a cost-effective way.

The DataLase imaging process is a new alternative to conventional printing methods. The technique features a patented ink that changes color on exposure to a low-power CO2 laser for the high-speed printing of variable information. It works by the application of the DataLase ink onto a specific area of the packaging, either by the converter using a standard printing process like flexo, or via a proprietary DataLase-coated tape. On the final production line, a computer-controlled, low-level energy beam emitted from an industrial CO2 laser ‘writes’ the required data onto the mark area, causing a color change reaction of the coating from white to black. A positive contrast image is produced.

By using a low-powered laser, there are significant cost and energy savings compared to powering a standard printing laser. Moreover, the process requires no inks, ribbons, applicators or other costly consumables, making it much simpler, cheaper and more environmentally friendly than traditional printing techniques. The laser-based print engine is highly efficient, with almost 100% production up-time. The lifetime of the laser is over 30,000 hours and, since imaging occurs without contacting the substrate and packaging, the laser requires little maintenance and no replacing of print heads due to wear and tear. Substantial cost savings of around 30-50% for a medium-volume line can be achieved with an investment payback time of less than a year.

Unlike some printing inks or ink-jet fluids, the Data-Lase laser-marked image is not prone to ‘bleeding’ on absorbent substrates. The technique is high speed and digital. Typically, it takes less than two seconds to produce bar codes with much higher resolution than with traditional technologies, meaning that the bar codes can be machine read virtually every time.

The DataLase imaging process also allows for late pack customization to take place at any point in the packaging line. The process is a reliable method for printing market-specific data onto packs already bearing generic info on them, thus reducing waste and saving money. Any changes can be easily programmed into the system, enabling the process to produce customized data on the pack without the need to stop the production line and go back to the start of the packaging production process.

There are three main variations of the DataLase imaging process to cover every printing need. DataLase PACKMARK™ applies high-speed, on-demand variable information such as bar codes, date, lot codes and use-by dates to primary packaging using the DataLase pigment. The process demonstrates high-speed marking capability and excellent resistance against rubbing for maximum brand protection. No additional printing foil is required.

DataLase CASEMARK™ Flexo is applied directly to the corrugated packaging and delivers a consistently verifiable bar code on-line and direct-to-carton. It is a fully integrated process that produces high-resolution images. Historically, it has not been possible to print data directly on to corrugate. With ink-jet, the ink has a tendency to bleed and thus render the bar code unreadable by machines. Laser printing is also not capable of consistently producing codes that are machine-readable. If the bar code is not readable, the retailer will fine the manufacturer and also charge them for return of the goods. DataLase CASEMARK Flexo produces a consistently high-resolution bar code on the carton that does not “bleed” on the highly absorbent corrugate material.

Finally, DataLase CASEMARK Tape contains the ink and enables the manufacturer to apply the tape and “print” the information all on the production line. The DataLase pigment is integrated in the tape material, making it possible to laser through its polypropylene surface without affecting it, encasing the image within the tape. This image is integral to the substrate and therefore cannot be removed; not even with chemicals or solvents. In addition, if the tape is removed, the image is permanently transferred to the box.

New techniques have been designed not to replace conventional printing methods, but to complement them and to add substantial benefits. Despite their limitations, traditional printing techniques still have a place alongside new, "smart" technologies such as DataLase.

The DataLase process enables companies to image high-quality, reproducible data onto both primary and secondary packaging at any point in the production line. Companies can also enjoy substantial benefits by integrating DataLase into their existing printing process, as well as using the innovative new technique to apply high-quality variable information to primary and secondary packaging.

More information about the award-winning DataLase process is available at www.datalase.com or by e-mail at usainfo@datalase.com (for United States) and info@datalase.com (for all other enquiries).

Background to DataLase

DataLase, the originator of the award-winning DataLase process, is a fast-growing technology company, providing patented, innovative laser marking solutions across a diverse range of sectors. With its headquarters in Widnes, UK, DataLase also has a significant U.S. operation based in Atlanta, GA. The patented DataLase process is suitable for applications including product identification and anti-counterfeiting. The company’s product range incorporates specialist solutions for primary and secondary packaging, as well as alternatives to print-and-apply labels. DataLase is also developing applications such as direct tablet and food marking as well as full color printing for the future.