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API's Holonique consultancy produces holographic effects such as this condensation
No single effect screams luxury quite as effectively as a nice bit of foiling on the packaging. Nessan Clearly looks at how printers can add a little shine to their work.
There are a number of enhancements that converters can add to packaging or labelling to add value, including spot varnishing and embossing, but few are quite as effective as foiling. There are several uses for foiling, with the most obvious being to add the perception of luxury to products. But foiling can also be used as part of a security or anti-counterfeiting measure, especially when combined with a foil holograph. Typical applications include confectionery, tobacco and spirits as well as some electronic products.
There is a choice between hot foil stamping and cold foiling. Bodo Junge, product marketing manager for Bobst sheetfed with responsibility for die-cutters and hot foil stampers, said that the big advantage of cold foil is that it can be done inline, 'When the curing is done right then you can overprint the cold foil with all different types of colour and really beautiful effects.'
But he also said that cold foiling works best over larger surface areas, 'Modern hot foil systems can save foils very efficiently.' He explained, 'If you look at a hot foil stamping machine then depending on the layout you can advance the hot foil in a way that only the enhanced surface of the foil is used so there's a very small distance between the used and unused parts and only the part that is used advances, which saves a lot of foil.'
He also points out that a modern cold foil system should use indexing to brake the reels and allow for the cylinder gap, to avoid waste where the foil would otherwise be unused. Mr Junge argues that customers should consider the overall productivity, saying that a lot of cold foil machines are badly under-used. He added, 'Printing machines today are very productive but if you combine it with a cold foil system then you can slow down a highly productive printing machine.'
The nature of hot foil stamping also allows for embossing, meaning you can have both the shelf appearance and a tactile effect. Mr Junge said, 'You can create very fine detail where the foil is being overprinted. But to have very fine tactile effects, you need to emboss and this is where the advantage of a hot foil stamper comes in.'
Hot foil stamping is also better suited to producing security holograms. This is because it is easier to get accurate registration on the blanket with a stamping system. Bobst produces a number of hot foil machines with the most productive series being its Masterfoil, which uses dancer rolls to buffer the foil before its passed through the machine. This reduces the tension on the foil and allows for faster throughput. The foil is stored in external foil cylinders, which reduces the time for foil changeovers.
This Bobst Masterfoil is a highly productive wide web hot foil stamping machine
There is also an Expertfoil series, which has a
similar level of productivity. Mr Junge explained, 'The Expertfoil
can also read register marks so that the sheet is registered in a
perfect way for the foil embossing because the sheets are always a
challenge to register because the different processed steps follow
each other. The sheets are printed and then folded and embossed in
a second or third step so the big challenge is always to register
the print enhancement perfectly to the printer.'
Looking at narrow
Pantec GS Systems sells the Rhino, an in-line flatbed multi-foil embossing system. It offers registered 3D foil and micro-embossing in combination with different foil colours, as well as 3D lenses at full speed, all of which can be done in a single pass. There are over 80 of these installed worldwide.
Pantec has recently launched a new, faster Rhino IIS aimed at the narrow web wine and spirits labels market. The new version is capable of 30,000 strokes per hour, 70% faster than the original machine and 20% faster than the Rhino II that was launched two years ago. It can also handle a higher embossing tonnage. It has a 410 x 410mm stamping area, with revolvable head, registered hologram streams and six independent heating zones.
Peter Frei, Pantec's CEO said, 'Flatbed stamping is an 'art', leaving a lot of space for creativity. The versatility of Rhino offers printers the ability to consult their customers with effects they develop and offer as their unique knowhow. The brand designers like using unique effects. Consequently, more and more they go for eye-catching effects to increase sales. Along with small, low cost tooling and short single pass delivery time, printers make themselves unique to their customers. Both brand owner and printers profit.' It should be available from February 2018.
Newfoil also offers a range of servo-driven machines that offer flat bed hot foil stamping combined with embossing in widths from 175mm to 340mm. The machines work offline so that they are not trying to keep up with a flexo press. Managing director Derrick Evans estimates that this approach is about 10% of the cost of using a rotary die. He said, 'We think the flatbed system is good for up to 50,000 impressions. Above that you have to consider whether rotary will be more cost effective.'
This image shows Pantec's Rhino II running inline with an Omet XFlex narrow web press
Of course, the other alternative is cold foiling. Mr Evans explained, 'Hot foil uses heat and pressure to transfer a vacuum deposit foil on the label. For cold foil we print an adhesive to the label and then run cold foil over the top of it through a heated roller so the adhesive picks up the foil from the film and transfers it but you get a more glossy finish not the superb shiny effect that you get with hot foiling.'
Naturally the foils themselves are a major part of the equation. There have been a couple of new foils announced this year. At Labelexpo Europe, Univacco released a new version of its CF4.6R-A narrow web cold foil. This is said to have very good overprintability, with good coverage of broad areas as well as fine detail together with sharp edges and smooth lines for both text and graphics. It is said to work at high speed and to offer good workability for quick job set-ups. It is suitable for use with most common substrates, including self-adhesive labels, shrink sleeves and PE tubes.
API also recently updated its TA+ cold foil. It is said to offer pack designers and printers exceptionally fine detail and the capability to cover large solid areas, as well as outstanding over-printability, meaning there is no limit to the range of colours and effects they can produce. It is designed for sectors whose products require filmic labels, such as personal care, drinks, household care. There are a number of colours, including silver and gold. David Peters, creative development manager at API, said, 'We're also including Oasis Copper as we've seen growing interest and demand for copper foils in recent times.'
The company also offers a custom decorative holograph service, Holonique Boutique, through which it provides customers with its expertise in the use of holography and 3D designs. Mr Peters explained, 'Many people can design in 2D, but designing in holography is really about controlling light, and therefore requires incredibly specialised knowledge, capability, and processes. It can also be used to create new and interesting wallpaper/unregistered patterns. Industry classics like Rainbow, Microglitter and Pillars of Light are ubiquitous, but if a brand wants something new to fit a fashion trend or something seasonal, then we can create that pattern in a foil or film for use on cartons, labels and so on.'
Earlier this year, Leonhard Kurz showed off a new Foilconnect program for calculating foil requirements. It is designed to help users work out the best way to optimise hot stamping foil usage. It calculates the required foil quantity and shows the most favourable foil advance mode and optimal axis configuration. It also generates a project sheet that can be used to set up the stamping machine.
Foiling remains one of the most cost-effective ways of adding value to a label or package. Cold foilers tend to be cheaper, but hot foiling generally gives a better finish and can usually be combined with embossing, giving both fine detail and an added tactile effect.