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Briefly discussed below is the process of making a typical two-layer
“Embossing Reflection Hologram”, by far the most common and cost-effective
hologram, with two common sub-types, namely the two layer hologram (with a background image and a foreground image) and the
three layer hologram (with a background image, a middle ground image and a foreground image).
 Making the Artwork: Using computer graphics, the artwork is generated on the computer on the basis of a conceptual design, wherein certain parts of ‘the matter” which the customer would like to appear in his hologram are recorded in the background (the bottom layer) and certain other parts in the foreground (the top layer).
Making the artwork “camera ready”: Using the computer graphics and keeping in view the shape and size chosen by the customer for his hologram, as many impressions of “the matter” of each layer as can be accommodated on an area of roughly six inches square, are separately recorded on paper.
Image-Setting: Using the special cameras to make “the positive” and “the negative” of each layer from the camera-ready artwork.
Holographic Recording and Master Origination: Exposing “the positive” of each layer, one after the another, to laser light with the aid of specialized imaging devices such as specialized lenses and mirrors and recording the same on a surface of an ultra clean, photo sensitive and specialized glass plate, to originate “the Glass Master”. At the end of this intricate and time-consuming process, the original two dimensional image of the artwork gets “transformed’” into a “three dimensional” impression on the surface of “the glass master”, called the hologram. The hologram will diffract the seven colours of the spectrum (colours seen in a rainbow) and will produce “the depth effect” or the three dimensional (3D) effect, when it is viewed from different angles under any type of natural or artificial light, thereby giving it an extraordinary visual appeal.
During holographic recording, secret information (e.g. code number) can be recorded and concealed in one of the layers of the hologram
to make it machine readable only (that is, under special lighting conditions and with the aid of special viewing instruments) in order to impart the inimitable “optical security feature” to the
hologram.
Plate/Shim Making: Transferring the multi-coloured, three-dimensional impression of the hologram from the surface of the
glass master to the surface of a nickel plate to create
“the nickel master”. (After this, the glass master cannot be used any further and has to be discarded.). By the same process and from
“the nickel master”, additional nickel plates, also called
“shims” are prepared for ultimate use in the embossing machine for mass production.
Embossing: Transferring the multi-coloured, three-dimensional impression of the hologram from the surface of the shim to the surface of very thin, metallised polyester film roll, through optimal application of heat and pressure. A special chemical coating known as “Tamper Evident Coating’” on the base of the polyester film imparts an important additional security feature to the hologram, to detect any attempt at its unauthorized removal from the surface of a product or of its packaging or of a document.
Adhesive-coating and lamination:
(only for pressure sensitive label only): The “embossed” roll is continuously coated on its reverse with a water-based
/ solvent-based pressure sensitive adhesive and dried and is thereafter continuously laminated with the silicon-coated surface of the release paper to make a laminated roll.
Die-Cutting: After lamination, the laminated roll is then duly
in the size and the shape required by the customer by a very specialized
automatic die-cutting machine. For jobs required in Spool Form the
laminated rolls are slitted as per size. Holograms in Sheet Form
are best suitable for manual affixations while Spool Form for
automatic affixations.
Finishing: Removal of the un-embossed portions of the metallised polyester film from and side-trimming of each sheet bearing several pieces of the hologram to make the sheet uniform in size and facilitate removal of holograms, one by one from the surface of the sheet.
The holograms are then finally passed through the quality control department, where each and every property of the hologram is thoroughly checked and finally these holograms are counted, packaged and shipped.
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Manufacturing Process