Holography materials

Lamination

Temporal Lamination

Holography materials are manufactured on glass and TAC film substrates. The temporary film lamination technique described below is an alternative to the well-known index matching technique and is easier and less time-consuming. The technique is appropriate for film sheets of 20x30cm or larger.

We recommend using an electrostatic transparent film similar to the 5105CL Penstic Transparent film from Molco GmbH (www.molco.com), Germany (Note: PENSTICK 5105 CL is now replaced by PENSTICK 5155 CL. (6 MIL instead of 4 MIL)). The procedure is as follows.

1. Clean a glass plate and place it horizontally. The plate should be slightly bigger than the actual film.
2. With a soft brush create an electrostatic charge on the glass plate.
3. Apply the electrostatic film to the glass plate with a (photographic) rubber roller making sure that you eliminate all the air bubbles.
4. Again take a soft brush and create an electrostatic charge on the electrostatic film.
5. Apply the holographic film to the electrostatic film with the rubber roller making sure, once again, that you eliminate all the bubbles.
6. Now use the glass plate as you would a normal holographic plate.
7. After making an exposure (and latensification) simply peel off your photosensitive film and process it as described in this web site.

Another technique useful to achieve the necessary flatness for the recording of film holograms smaller than 20x30cm is to put the film between two glass plates.

Final Lamination

The emulsion of holograms made on film and glass plates should be protected from humidity and UV light. The diffusion of water into the emulsion leads to the colour of the hologram changing. UV radiation causes hologram brightness degradation (the "print out" effect). In order to protect the hologram from these unwanted effects one may cover and seal the hologram on one or both faces. In the case of glass holograms sealing from the back side is sufficient whereas film holograms should be sealed both from the front and the back.

The best way to protect the back side (the emulsion) of reflection holograms is by lamination of a black self-adhesive film. We recommend Black Oracal 641-070M from Orafol GmbH, Germany (www.orafol.de), or a similar product. It is straight-forward to apply this black film to the emulsion side of the hologram using a photographic rubber roller. Alternatively a cold lamination machine may be used. The result is a sandwich consisting of the holographic substrate, the emulsion and the protective film.

For emulsion protection of transmission film holograms we recommend the use of a transparent double-sided self-adhesive film (e.g. Optimount 60238 from Hunt Graphics Europe Ltd.) and a Plexiglas sheet (e.g. Plexiglas XT, from Rohm GmbH, Germany, www.roem.de).

One side of the double-sided film is applied to the emulsion side of the hologram and the other side is stuck to the Plexiglas. This can be done either by hand (rubber roller) or by using a cold lamination machine. The result is a sandwich consisting of holofilm substrate, emulsion, adhesive and Plexiglas.

In order to insure flatness of film reflection holograms the same technique of mounting to a Plexiglas sheet using a doublesided film may be used. The result is a sandwich consisting of the film substrate, the emulsion, a black self-adhesive film, the double-sided self-adhesive film and finally the Plexiglas sheet.

Front-side protection of the hologram from UV radiation can be effected by use of the standard UV reflecting films available from Edmond Scientific(www.edsci.com).