Dai Nippon Printing Co., Ltd. (DNP) has developed world’s first transparent Lippmann hologram transfer foil targeting passport uses.
In addition to the visual effect of Lippmann holograms such as realistic three-dimensional expressions which can be observed when the viewpoint is shifted in vertical and horizontal direction, DNP has achieved enough transferring performance for continuous lamination on the surface of the passport data page.

[Developmental Background]
Passports from countries around the world generally require high level security measures in order to prevent counterfeiting. In many cases this is achieved via the use of an embossed hologram transferred over the entire face of the data page, which includes personal information. Embossed hologram transfer foil has been widely adopted based on its excellent mass production qualities, and high level security. In recent years, however, there have been increased instances of the counterfeiting of passports which use embossed type holograms, leading to demands for hologram technology capable of achieving even higher levels of security. Lippmann hologram transfer foil requires special materials and manufacturing processes, and as a result is more difficult to counterfeit than embossed type holograms. However, as image recording of Lippmann hologram requires a specific thickness of the material, it has been difficult to cut the material when laminated.
DNP developed the suitable material for Lippmann hologram transfer foil, as well as the efforts to improve manufacturing processes. As a result, world’s first Lippmann hologram transfer foil manufactured by DNP has satisfactory workability for lamination and sophisticated security performance.

[Features]
Counterfeiting Lippmann hologram transfer foil is extremely difficult since it requires specialized material and manufacturing processes, and very few companies have the technology to process this type of hologram into transfer foil. Lippmann holograms have the superior three-dimensional effect compared to embossed holograms, and its distinguished visibility enables the authentication at just a glance. By incorporating the various holographic image expressions and combining with other security technologies, it is possible to achieve even more sophisticated anti-counterfeiting effects.

Various holographic image expressions

• Image switching
  Multiple different three-dimensional images can be displayed in the same position on the hologram, which are switched by shifting the viewing angle in vertical or horizontal direction.
  
• Micro-text
  Micro-text of approximately 250 microns, which is difficult to read by naked eye, can be recorded as a holographic image. By employing electron beam lithography, it is also possible to incorporate extremely fine patterns into the hologram.
  
• Laser reconstruction image
  By irradiating laser beam at specific areas of the hologram, hidden logo or images could be reconstructed in the reflection beam.
  

Combinations with other security technologies
It is possible to further increase security attributes by combining the Lippmann hologram transfer foil with the following printing technologies;

• Optically variable ink printing
  Incorporating the special ink which color changes when the viewing angle is changed.
• Fluorescence emitting ink printing
  Incorporating the special ink which fluorescence is emitted by ultraviolet light or infrared light irradiation.

[Future Developments]
In addition to embossed hologram transfer foil, DNP will also promote sales of the Lippmann hologram transfer foil for passport uses. The company aims to commercialize the newly developed Lippmann hologram transfer foil via joint efforts with passport printer manufacturers responsible for passport issuing operations and system integrators both in Japan and overseas, targeting sales of approximately 500 million yen by the year ending March 31, 2013.
DNP also plans to display the Lippmann hologram transfer foil at CARTES & IDentification 2009 set to take place in Paris, France between November 17 and 19.

[Reference: Regarding Holograms]

Lippmann Holograms
The surface of a film is coated with a special polymer layer, and interference patterns produced via changes in the refractive index within the polymer layer. Lippmann hologram images are reproduced via diffraction phenomenon by inserting light into the interference patterns. Holograms offer superior in-depth full parallax effect and it is possible to obtain three-dimensional effect which more closely approximate real life objects. Lippmann holograms use special materials and manufacturing processes, making them extremely difficult to counterfeit. Lippmann holograms have also developed a global reputation for security performance, including design attributes, by facilitating the unique expression which produce realistic feelings of in-depth full parallax effect.

Embossed Holograms
Embossed holograms record optical interference patterns on the surface of the film as fine concavo-convex shapes, and as the colors change into rainbow hues depending on the viewing angle, it is possible to express horizontal three-dimensional effects. Embossed holograms have superior mass production attributes, and are currently used in a broad context not only for anti-counterfeiting uses, but also in design purposes.