Polycarbonate has long established itself as the preferred material for national ID cards and passport datapages, with suppliers now offering an extensive range of polycarbonate-based features to meet the ever-increasing demand to provide easy authentication of documents whilst making the document itself more secure and difficult to alter.
Superior to other plastics and composite materials, polycarbonate boasts unique optical and physical properties says Demax. Its high temperature and impact resistance allow for the production of long-lifespan travel and identity documents, whilst the ability to embed visual security features within its structure makes it ideal as a substrate for high-security government-issued documents. The layers that make up the polycarbonate card or passport datapage are fused together during production and cannot be pulled apart individually. The optical imagery contained within the card structure cannot easily be accessed or tampered with using any mechanical means, providing a robust solution for securing personal data against any form of manipulation and attack.
Traditionally, DOVIDs (Diffractive Optical Variable Image Device) in polycarbonate documents have, however, been limited to localised applications integrated into the card body as hot-stamping foil in the form of a patch covering, typically, part of the document holder’s image and some of the biographical data.
As a result, this has confined DOVID design and its visual effects to an area of around 20x20mm, limiting the full potential of DOVIDs and what they can deliver optically. Another major drawback has been the use of adhesives which are known to impact the optical brightness of the DOVID over time.
The E-LIDOGRAM Polycarbonate Inlay is a new generation of ultra-secure optical solutions for government-issued documents. The new offering introduces an array of state-of-the-art features spread over the entire surface of the card or passport datapage, providing enhanced visual effects for reliable, unambiguous and quick first-line authentication of travel and identity documents.
Unlike traditional solutions, the optical nanostructures are embossed directly into polycarbonate without the use of adhesives, and integrated within the card or passport datapage during the standard collation and lamination process, guaranteeing full brightness of the imagery for the whole lifespan of the document.
The features can be placed in any arrangement across the whole of the card or passport datapage, giving DOVID design a wide spectrum of possibilities and high visual impact. As a result, says Demax, the imagery creates an organic unit with background graphics and individual security elements to deliver superior optical effects and tamper-resistant security for polycarbonate documents.
Demax uses the latest generation of e-beam lithography for origination, which achieves a line width resolution of 8 nanometres, allowing unique and differentiable features to be produced. With high-resolution vector-based graphics, the system writes nanoscale patterns producing subwavelength structures with visual effects that are distinct from conventional holograms.
The technology is marketed by Demax as the E-LIDOGRAM® and offers a range of overt features, including non-iridescent colour-shifting effects such as green changing to red and vice versa; multicolour-shifting effects such as pink switching to green, violet, blue or yellow depending on the viewing angle; motion-type features with objects displaying full displacement in their apparent position from left to right, up to down and vice versa when the document is tilted; as well as three-dimensional effects reproducing lifelike appearance of objects; pastel colour based features and the diffractive black used to recreate the intricate detail of individual elements such as facial features.
The E-LIDOGRAM inlay comes with a gamut of these as well as more traditional diffractive effects depending on customer requirements, which can include bright iridescent animations, kinetic and flipping images, metallisation, lens effects, covert laser readable images, micro text and nano graphics. The product is supplied pre-embossed on polycarbonate in reel or sheet form depending on equipment used in card production.