The NW2000 Holographic Embossing Machine has been designed to replicate holographic and diffraction type images which have been produced onto what is referred to as a 'shim'. Normally this is a 150 x 150 mm square nickel sheet approximately 0.06 mm thick.
The holographic master is originated onto a glass plate coated with photoresist and, once developed, is then metallised and placed in a plating tank where a 'mother' shim is grown.
This is produced by a process known as 'electroforming', (a precision form of electroplating).
The mother is then used to produce 'daughter' shims which are used for production.
It is done this way so that, should anything untoward happen to the production shim, another one can be grown from the mother.
Two shims are then fitter to the NW2000 die roller for embossing the image into the metallised polyester film.
Production shims, if treated with care, can be used to manufacture some millions of metres of material before fading into retirement.
The NW2000 produces embossed material at up to 30 metres per minute.
One of the design features of the NW2000 is that images can be arranged onto the shim which, when placed onto the die roller, will give precise registration onto the finished roll.
This has the advantage that 'down stream' processing can be done more easily than with conventional systems where optical registration has traditionally been required to overcome variations in image spacing. However, registration marks can be placed onto the image at the mastering stage should they be required.
Although nominally used with industry standard 150 mm wide shims, the NW2000 Die Roller will accommodate shims up to 200 mm wide, but the repeat length is 157 mm, which comprises 154 mm maximum image length plus a 3 mm joining gap between the shims.
For specialist applications, die rollers can be manufactured
with a single join gap giving 314 mm repeat length.