
Many self-adhesive products are available to design advertising graphics for shopping windows and showcases. Since inkjet printers using solvent inks have been available in the market, low-volume graphic prints can be cost-effectively produced. However, most existing materials lack the transparency required to convey the impression that a pane has been printed upon without the print medium being visible.
Step 1 The Basic Material | Crystal-clear and inherently stable, polyester film has successfully been used by Regulus customers for a long time. The downside: Solvent inks cannot be directly printed on this type of film. An ink-receptive layer is required.
Step 2 Ink-Receptive Layer | Crystal-clear coating suitable for any solvent ink is not available in the market as a ready-made solution. At the Regulus laboratory, chemists have spent some 20 years developing ink-receptive layers that ensure optimal drying and brilliant colors with a variety of inkjet systems. Since 2006, the portfolio has included a crystal-clear layer for solvent inks that has been optimized for use with PET film.
Step 3 Glueing System | This type of application makes particularly tough demands on the glue used: It must be highly transparent and immune to large fluctuations in temperature, must not become yellow when exposed to ultraviolet rays, and should be removable from glass without any residue after having been applied for months or years. In collaboration with a glue maker, suitable glue was selected. Achieving the required level of transparency calls for the use of solvent glue that allows mounting on a wet pane to prevent any air bubbles from becoming trapped.
Step 4 Covering Material/Release Liner | The glue surface will only be crystal clear (a familiar phenomenon called a „no label look“ in the label industry) if the covering material will not impart any structure onto the glue. Due to its paper fiber structure, siliconized paper fails to meet this requirement. Thus, siliconized polyester film was selected.
First, small-format lab samples are made that must undergo internal testing and are subjected to an initial assessment by market experts (lead customers). If these tests are positive, at least two small batches are made under regular production conditions. Regulus coating technology is suitable for almost any combination of coating chemistry and material. However, a desire for doubly transparent glue and surface coatings poses a tough challenge especially for manufacturing technology.
First series samples are made available to a group of interested beta testers. At the same time, an independent institution (in this case the Bavarian State Trade Agency) tests the material’s durability in a situation where exposure to the elements is simulated. Only once all testing has produced positive results and it has been determined that those results can be reproduced, is the product released for production and marketing.
Collateral brochures, sample prints, product information is produced and customers are trained in application technology in collaboration with leading trade magazines. In its go-to-market year, the Dialux® SIGS product becomes the focus of Regulus’ presence at the leading trade fairs for digital printing technologies.
The trade press unanimously recognizes the product’s innovative character and the new universe of options it has created for window advertising. The 2008 edp Award in the “Best Indoor Media” category at the Drupa trade fair represents a particular highlight.