Options and opportunities for digital print finishing

So let’s look at conventional label finishing first. References to some of the newer solutions for wider format folding cartons and flexible packaging follow later.

LABEL FINISHING

Currently, around 80% to 85% of all the 2,000 or so digital label presses that are installed and operational in the global label industry today are running with off-line finishing capabilities. That has been the route that the majority of HP Indigo customers have chosen, with their partner suppliers providing the digital finishing equipment. Other digital press manufacturers  such as Xeikon are using different solutions and aim to provide a complete printing and converting line.

Some of the latest inkjet presses are now being supplied with in-line digital finishing. However, at the present time, the total installed base of stand-alone digital label presses is still predominantly with off-line conventional finishing. This can be seen in Figure 7.1.

IN-LINE OR OFF-LINE

Working offline certainly gives the opportunity to have much more flexibility. The more complex the label job, then the more the converter to-date has looked at an off-line finishing scenario.

As digital presses get faster (up to 60 or 70 meters a minute or more) so the converter will have a very good reason to want to run in-line. It will largely depend on the type of work being produced. ABG International for example, have to date installed well over 700 finishing lines in digital label converting plants in some 65 countries – relatively few of those have been in-line systems.

If jobs predominately just require flexo varnishing and die-cutting, then in-line may well be the best option. The more processes required in the finishing line (foiling, foiling, embossing, etc), the more it is likely to slow the digital press speed down, which negates the need to have a press running at 50-60 meters or more a minute. If changeover and set-up on the finishing line is longer than the press changeover time, then off-line finishing probably makes the most sense.

In-line finishing however, does offer key advantages. The converter will get from the beginning to the end of the job in one operation. With the new generation of faster digital label presses the ability to print and ship without a separate finishing operation is a definite advantage – providing the press and output is not substantially slowed down by the finishing requirements. Certainly this is the route that, say, Xeikon and Nilpeter have followed.

Laser die-cutting in-line is also becoming ever more attractive as inkjet speeds rise, and also when jobs can be batched or ‘Ganged’ on the web. Doing everything in-line also means that it is possible to modify the pre-press or image to match the die-cutting or the hot stamping, or to a screen edge. That’s not possible if the job has already been printed and just requires finishing off-line.

The choice of in-line or off-line may also depend on how many digital printing machines a converter operates. With multiple digital printing presses it may be more feasible to have one or two off-line finishing systems servicing 3, 4 or 5 digital presses – even providing finishing for conventional presses where more complex finishing operations are required.

What is important is that the converter looking to invest in digital printing technology initially makes a good case for either in-line or off-line finishing depending on his customer requirements, the markets served, the complexity of work undertaken, the number of digital presses, etc.

RANGE OF FINISHING OPTIONS

While a die-cutting capability – which may be flatbed, rotary, magnetic cylinder or increasingly, digital using laser cutting – is a primary requirement of almost all digital label presses, it is almost certain that other finishing capabilities will also be required for many end-use applications. Certainly, the minimum that the converter will need to have, whether off-line or on-line with digital finishing, is die-cutting, but the great majority of the presses will all also have a requirement to do varnishing – commonly UV flexo varnishing.

So, effectively, there are the two minimums for all finishing operations on label digital presses: die-cutting and varnishing. Almost all the finishing machines installed to date have both these options as standard, as well as web-handling, edge trim, matrix strip, slitting and rewinding. In essence, a basic off-line finishing machine for self-adhesive labels will likely include:

• An unwind

• Web handling

• UV flexo varnishing

• Semi-rotary die-cutter

• Liner score/edge trimming

• Matrix stripping and matrix rewinding

• Slitting and rewinding into finished rolls.

Depending on the market sectors that the converter is involved with, so other finishing operations will be required. Hot or cold foiling for the cosmetics or wine and spirits sectors; possibly embossing for those same sectors as well; maybe sequential coding or numbering for pharmaceuticals; perhaps a vision system for web inspection; sometimes over-laminating. All of which will add to the converter’s digital print finishing capabilities.

Put together, a label converter may wish to build a finishing capability that will differentiate them from competitors, or create a finishing solution to suite a particular market or markets – even a key market application or job. Key tools for this differentiation may then look to include some or all of the following features:

• In-line finishing

• Full rotary die-cutting

• Screen printing

• Spot varnishing

• Cold foiling, hot stamping, embossing

• Carton, blister pack, shrink sleeve,

• pouch or sachet finishing

• Vision system

• Laser die-cutting

When looking at building a digital finishing line there are other items which the converter may well wish to consider. These are: whether the die-cutter for digital finishing can use existing tooling from the converter’s conventional presses. Similarly, can the foil units use most of the existing tools from the conventional presses and whether they incorporate foil saver and dispro adjustment?

Digital finishing lines will all obviously require a rewinder, or more commonly a slitter rewinder – with automatic tension adjustment – while stand-alone finishing lines will additionally need to incorporate an unwind unit with web guide for perfect registration. Some may be configured to incorporate corona treatment, chill drum and web cleaning.

A guide to the usage of the main finishing capabilities on the current installed base of standalone full-color digital label presses can be seen in Figure 7.2 which is based on research in recent years by InfoTrends and on recent industry analysis by Labels & labelling Consultancy.

In addition to the specific finishing capabilities shown in the chart, some label converters with digital printing presses may wish to incorporate one or more conventional printing processes into the finishing line to add value or special effects for, say, high-quality cosmetics or wine label applications.

Options may include full rotary or semi-rotary flexo with UV or infra-red drying; an optional spot varnishing station with servo-driven register control; flatbed or rotary screen module (the cost of the mesh, frame, pre-press and set-up will be cheaper with flat screen). Rotary screen may well be considered if large volumes and increased speed are required.

Cold foiling is also now successfully being undertaken with inkjet in the finishing line. The inkjet head puts the adhesive down and so cold foiling is effectively done digitally. The down side at the moment is the cost of the consumables – the inks, the varnishes, the adhesives are far, far more expensive than customers and converters are traditionally used to paying for them. It’s a cost factor; it’s the ink suppliers and the adhesive suppliers that are going to have to drive the price down further before the process is to become much more successful.

Looking across the key suppliers of finishing lines for digital label printing – such as ABG International, Grafisk Maskinfabrik, Delta Industrial Services, Cartes and SMAG, there are also a range of additional optional label finishing units that can be incorporated.

Some narrow-web label converters may wish to use their digital printing and finishing lines for the converting of small folding cartons, packaging foils and sleeves. Both semi-rotary and full rotary carton units are available from some of the leading finishing line suppliers. Semi-rotary offers lower tooling costs and easier die storage. Full rotary gives a higher throughput.

Depending on the manufacturer, other options can include hot stamping (see illustration below), missing label detection, waste shredding, slot die, undercut scoring, folding, turret unwind/rewind, ultrasonic welding, conductive inkjet printing, coating, hot and cold lamination, fully integrated camera inspection systems, JDF connectivity to the DFE and fully automated flexible die load/unload.

As can be seen, pretty well any finishing technology that a converter may require can now be supplied by one or more manufacturer. The converter is therefore well advised to look at what different manufacturers can offer and match these to their specific production and customer requirements.

The potential to make use of such options to add value and increase profitability is greater today than it has ever been.

MODULAR SYSTEMS AND SUPPLIERS

Most suppliers (probably all) of digital print finishing/converting equipment offer modular base systems to minimize initial investment but which can be added to or expanded (with any of the options already outlined) as and when the converter grows or when customers or applications demand additional finishing or added-value capabilities. Most will also offer options for in-line or off-line finishing equipment. So let’s look in more detail at the key digital label print finishing equipment suppliers and what machines and models they provide.

ABG INTERNATIONAL DIGICON FINISHING EQUIPMENT

Digicon-Lite

For converters looking for an entry level machine to convert digitally printed webs ABG International offer the Digicon-Lite (shown below).

Despite the small foot-print of this machine it is still capable of carrying out varnishing, coating and converting functions

Digicon Series 2

At the other end of the market requirement for digital finishing equipment the ABG International Digicon Series 2 machines are claimed to be amongst the most advanced and diverse on the market. Being fully modular the Series 2 provides options including hot foil, cold foil, flexo stations, flatbed applications, screen printing, lamination modules, camera systems and a whole lot more. Modular units allow retrofitable options from hot foil, cold foil, flexo stations, flatbed applications, screen printing, lamination modules, camera systems and other options as required. Key technical specifications for the Digicon can be seen in the table below:

The Digicon Series 2 machine (example shown below) combines semi-rotary technology with accurate re-registration modules for a variety of digital converting applications.

DELTA INDUSTRIAL SERVICES SPECTRUM

Delta Industrial have a digital print finishing unit (the Delta Spectrum®) which they describe as the ultimate finishing solution.

Technical specifications include options for flexible die technology in semi-rotary mode or traditional die-cutting in full rotary mode. The unit can be used for in-line or off-line production.

Like other suppliers they have a range of finishing modules that have been developed over the years – all of them servo-controlled – and the company will custom design and automate to a customer’s specific requirements: as simple or as complex as required to meet specific label finishing needs. Options available include varnishing, die-cutting, cold foiling, embossing, spot varnishing, turret unwind/rewind, folding and waste stripping. Process modules may be easily added and moved.

To help guarantee quality Delta Industrial Services can also incorporate a vision system, either for visual inspection by the operator, or fully automatic, with automatic detection with reject capabilities.

Standard press width is 330 mm (13 inches), but other widths are available on request. For converters that want to add a 2D barcode or something at the last instant, Delta can offer in-line digital printing  typically using inkjet print heads that are UV cured. The Delta Spectrum® can be seen in the following illustration.

SMAG DIGITAL GALAXIE

Also on the market is the Digital Galaxie from SMAG, another of the suppliers to the digital printing and finishing sector. SMAG is offering several product ranges from simple, compact and productive entry level with semi-rotary or full UV flexo varnish, lamination and semi-auto die-cutting up to a high end state-of-the-art solution, the Digital Galaxie, which is a more flexible machine with different types of add-in modules – such as semi-rotary or flatbed foil, embossing, flatbed screen, lamination and cold foil and a 100% inspection system in cooperation with AVT – to bring the line closer to the capabilities of a conventional press And finally a priming range in order to prime the material in or off-line.

The Digital Galaxie has been developed on the Galaxie press base (of which more than 200 units have been installed) but adapted for digital printing. Thanks to its silk screen technology, the machine is able to bring added-value to products – including matt inks, tactile effects and thermochromic effects.

Maximum web width is 350 mm, with a running speed of up to 45 m/min.

SMAG has more than 80 installations in Europe and worldwide of the Digital Galaxie converting machine.

GRAFISK MASKINFABRIK DIGITAL FINISHING MODULES

Another company with a substantial installed base (now over 200 machines) of digital finishing equipment is Grafisk Maskinfabrik, whose range of machine models includes the DC330, the DC330mini, the DC500, the LS500 and the XP560 with web widths up to 560 mm. Specifications can be seen in the following table.

Standard finishing options on these machines provide for varnishing, die-cutting, hot and cold foiling, embossing, waste stripping, screen printing, RFID, slot-die, laser cutting, hot glue and flexo printing. Other options available are sheeting, either in-line or off-line, lamination, self-adhesive lamination, UV lamination, missing label inspection, etc.

Non-label applications that can also be provided in the range are shrink sleeve and IML.

CARTES GT360 SERIES

Cartes provides modular machines configurable with hot stamping, silk screen printing, embossing, flexo varnishing, flat and laser die-cutting.

Machines are adaptable to all production needs thanks to their modularity and are renowned for the material saving – even on short runs – their mechanical toughness, high accuracy (even when printing at the maximum speed), their energy saving, and the high levels of operator safety.

The Cartes GT360 Series machines come with a web width of 360 mm and can run at up to 15,000 cycles per hour, either in-line or off-line. Apart from self-adhesive label production the machine can convert a range of other materials, including demanding materials like sandpaper.

Specifications for the GT360 are as follows:

Each printing unit works as an independent module, making it possible to insert, replace or add units irrespective of the original machine configuration.

GONDERFLEX INTERNATIONAL ROTOWORX 330

Previously part of the Durst digital printing and converting portfolio, the Rotoworx digital label converting and finishing unit was recently acquired by Gonderflex International, who have launched the new Rotoworx 330 semi-rotary die-cutting machine, with a flexographic unit performing spot or flood coating with redesigned UV and IR dryers.

The unit also features a new enclosed doctor blade system and equipment for cold foil lamination. Optionally, the machine can be fitted with a rotary sheeting station, shingling conveyor, in-line booklet labels production, semi-rotary hot foil stamping and rotary screen printing.

LEOMAT DIGITAKT 330 SFR

The Digitakt 350 SFR has a matrix rewind, printing unit, semi-rotary die-cutting unit, an AVT camera inspection system, cutting unit and rewinding unit. The machine is assembled modularly and allows simple subsequent integration of additional modules like hot stamping, screen printing, additional die-cutting, in-mold delivery system, label dispensing systems, etc.

BAR GRAPHIC MACHINERY BGM ELITE FDTR

Standard features on the Bar Graphic Machinery BGM Elite are being able to print to register, die-cut to print re-register and print-to-print re-register; the servo-driven print stations are equipped with self-positioning print cylinders enabling automatic print registration set-up.

The machine is fitted with interchangeable UV and IR curing cassettes, while dual servo-driven die stations with removable anvils enable all converting options to be achieved.

MATCHING FINISHING TECHNOLOGY TO MARKETS

The configuration of a digital printing finishing/converting machine is really dependent on the markets in which the converter is working: the main markets being food, wines and beverages, cosmetics/health and beauty and pharmaceutical.

Food

For the food industry most of the finishing machines installed to date tend to be relatively simple with a basic configuration of flexo varnishing, cold foiling and semi-automatic die-cutting.

Wines, spirits and beverages

For the wine, spirits and beverages markets the finishing machines are generally more complex – more and more features on them. With digital becoming increasingly in competition with conventional presses the same finishing features are being added to digital converting equipment in order to fight against conventional presses. So, in this market, there is now a lot of hot stamping, which may be flatbed hot stamping or semi-automatic hot stamping, both systems bringing their own advantages and disadvantages.

Cosmetics/health and beauty

Like the wines and spirits sector, cosmetics, health and beauty labeling is becoming increasingly complex. Again, more and more converting/finishing features are being added to the digital lines so as to compete with conventional printing – hot stamping, embossing, etc, in particular.

Screen printing technology is also very useful in the cosmetics market (wine too) in order to bring some added value to the finished products.

Pharmaceutical

In the pharmaceutical market there is commonly a requirement for screen to be added into the digital finishing line; sometimes flexo and from time to time, foiling. Anti-counterfeiting features may be added with a hologram stamping unit. For the same market it may also be necessary to integrate a 100% camera inspection system. Additionally a digital Braille system may be added – this is an inkjet type system that digitally puts down a raised Braille image.

WHERE NEXT FOR DIGITAL LABEL, CARTON AND FLEXIBLES FINISHING?

Digital print finishing has come a long way over the past ten years or so. Laser die-cutting is taking this even further, but where can we expect digital print finishing to be in the not too-distant future?

Undoubtedly, converting has been seen as something of digital print’s Achilles’ heel. Although digital print is instantly variable it still takes time to manually set up a pressure-sensitive label converting line, particularly where multi-process work is required.

However, according to ABG’s Keith Montgomery, speaking at a recent HP Indigo event in Tel Aviv, we can soon be looking towards the upcoming automation of the digital converting process. ‘The Idea,’ he explained, ‘is for full automation - to automatically load and unload flexible dies, to incorporate laser finishing, automated set-up of back-scoring, and repeatable auto-positioning of cutting wheels and slitting knives. We will also be integrating turrets into digital converting lines to improve uptime, and we will be looking at digital hot foiling before too long.’

Montgomery gave the example of typical manual changeover times: two minutes for a flexible die change, two minutes for back scoring, 5 minutes for slitting knives - 9 minutes in total. ‘With an automated set-up this takes just 45 seconds. If you’re saving even eight minutes per job, on 12 jobs a day that’s 1.5 hours across a shift. ‘

The driver for this future of full automation is JDF connectivity. ‘The MIS sends files to the digital converting system with information on repeat length, rewind shaft diameter and all other relevant data. The die line is sent straight to laser. The planning system knows which machines are free and fires the file to any available machine. JMF automatically updates the MIS with accurate job costing information and updated production information, all in in real time.’

Digital print finishing will almost certainly be different and more automated in the future. Laser cutting and other forms of digital print finishing will become widespread. With current progress in laser die-cutting now making the technology a more regular and commonplace part of finishing, it was therefore decided to devote a whole article to this. See the potential of laser die-cutting and digital finishing.

Let’s take a look at some of the companies and developments taking place in the wider format conventional finishing of digitally printed folding cartons and flexible packaging produced on the latest generations of package printing presses from HP Indigo, Xeikon, Screen Europe and Landa.

AB GRAPHIC INTERNATIONAL EDALE DIGICON 3000

A joint development project between Edale and AB Graphic International (ABG), the Digicon 3000 is a 762 mm wide finishing system that enables printers to convert pressure sensitive labels, flexible packaging and folding cartons printed on the new HP Indigo wider format digital presses.With both semi-rotary and flatbed options available the 3000 offers a choice of different finishing solutions.

Both options can be integrated into any Digicon configuration and can also be retro-fitted to existing Digicon series 2 machines. With a wide range of modular options for digital finishing, including varnishing, screen printing, embossing and hot foil amongst others, A B Graphic can now offer a variety of finishing solutions for digitally printed wide format cartons and flexible packaging.

By combining high end embellishments with low cost tooling, quick job change overs and minimising waste A B Graphic have been able to introduce the perfect solution for short run folding carton work.

The two companies together bring more than 100 years of combined technical expertise: ABG having worked with HP for more than 15 years and Edale through its collaboration with Agfa Graphics for more than 12 years. Whilst the Digicon 3000 will be manufactured by Edale, the machine will benefit from the companies' combined intellectual property. Working together has enabled the two companies to create an advanced product that benefits from the respective technology strengths of Edale and AB Graphic International. As a result the Digicon 3000 is packed with innovations that will serve to enhance and broaden the applications possible in mid web digital label and packaging printing,.

Specifications for the Edale Digicon 3000 are as follows:

KAMA PROCUT 53

Initially introduced at Drupa 2008, the KAMA ProCut 53 was presented as the world’s first automatic flatbed die-cutter, with a sheet format of 530 x 400 mm. This machine provides KAMA with cutting solutions up to their existing B2 and B1 size machines. The suitability of the ProCut 53 for finishing digital printed cartons has attracted the attention of the leading digital press manufacturers and close working relationships now exist with HP Indigo and Xerox as solution partners.

The ProCut 53 provides a flexible solution for all finishing tasks within the 530 x 400 mm sheet size, including cutting, creasing, perforating, kiss-cutting, cold embossing and Braille and is claimed to be profitable even with small and personalized runs, be it printed media or printed packaging, offset or digital printing. Specifications for the ProCut 53 are shown below.

BOGRAMA ROTARY DIE-CUTTER

Compatible with Xeikon Folding Carton Suite production is the Bograma Rotary die-cutter that has been developed for single-sheet folded box processing and for thin, folded products, using flexible dies. The machine can punch, kiss cut, perforate, crease and deboss, either manufactured one or multiple-up. A maximum product thickness of 0.5 mm can be punched. Formats can be processed between A4 and a maximum sheet size of 550 x 750 mm. The maximum production capacity (depending on material) is at 12,000 cycles / h.

In-line configuration of the die-cutter (as shown with the Xeikon folding carton press at Labelexpo 2013) is naturally the most efficient way to accomplish several work steps in one single step, thus achieving high performance. Automatic discharge of the section grids while at the same time breaking out the inner cuts optimizes production even further. Technical specifications are shown on previous page.

DELTA INDUSTRIAL

Delta has developed several solutions for the package and pouching needs of customers. Applications include hot seal packaging, cold seal packaging, reciprocating heat seal packaging, and part placement packaging options and are available as both standalone machines and quick change components, thanks to their modular design.

EMMENDINGER MASCHINENBAU

This company provides a high-speed punching and embossing machine that is used by companies in the packaging, dairy and beverage industries.

The machine punches small shapes out of unprinted and printed aluminium, paper and plastic foils, directly from reels, which may then be used as sealing lids or labels.

Applications include sealing lids for yoghurt and pro-biotic drinks and beer bottle neck labels. The machine provides capabilities for embossing, perforating, pin-perforating and doming, and quick changeovers between tools that enable easy handling.