Pressing the point

With digital printing technology becoming an increasingly common facet of the packaging production arena, the death knell of offset printing has been rung time and time again. And on the face of it, digital print offers packaging converters a wealth of new possibilities, sales avenues and applications.

By 2018, digital printing will equate to 50% of the global offset sector and even higher in the more mature print regions across the globe, according to recently published research. Smithers Pira report that the volume of all offset prints will have fallen by 10.2% across the world between 2008 and 2018, while digital print volume is forecast to grow by 68.3%.

So, is the future of packaging inkjet and electrophotography, while sheetfed, heatset and coldset technologies are committed to the scrapheap? Far from it.

Flexible production
One manufacturer that has enjoyed good traction in the offset packaging space is Comexi, which recently completed the installation of its first Offset CI8 press, a machine that was five years in development.

Installed at Spanish packaging converter Inplasca, the press was Comexi's recognition that the flexible packaging market was in need of a combination of high print quality, fast changeovers and the ability to use solvent-free inks.

Central to the Comexi offset press is a central impression (CI) drum and more important, its sleeve and servomotor technology. The C18 leverages light sleeves that are made from aluminium or PU composites, which means the continuous process that is typical of this type of printing becomes highly repeatable with the job changeover process streamlined.

According to the manufacturer, a run changeover can be performed in a matter of minutes, as the press sleeves can be prepared with the plates and blanket cylinders already in place. The servomotors present on the machine's individual printing cylinders, which are combined with Comexi's CI drum technology, are claimed to make it possible to configure press colour-to-colour registrations efficiently.

This also enables the operator to maintain registration accuracy throughout the entire print run - key in a challenging environment
where minimising product waste and efficient production are highly desirable goals in the pressroom.

Comexi has also highlighted the machine's attractive time to market thanks to the use of offset plates in production, rather than using flexo or gravure as required by other technologies. The manufacturer states that short and even medium print runs can be produced with lower costs per square metre while offset technology for printing on flexible material also improves print quality, owing to its
central drum and the range of screen technologies. The manufacturer states that the C18 press can reproduce 2% and 98% screens, and more than 80 lines/cm, which makes it compatible with the latest digital screening methods.

Proven technology
Arguably a mainstay in the field of offset technology for packaging, Goss International continues to push its Sunday Vpak presses and with great success.

The US-headquartered manufacturer explains that its Vpak platform is built from the ground up, which enables companies in the fields of flexible packaging, folding cartons and label production to leverage web offset technology when printing high quality work.

The Vpak platform integrates quick-change sleeve technology that matches the cylinder circumference on each job. By adapting its sleeve technology for packaging production, the manufacturer has developed a successful system that affixes a layer of 'white light', a material that sits under the blanket and plate sleeves.

By altering the thickness of this layer, fewer blanket bridging sleeve adapters are required in production, which results in a cost-effective alternative to purchasing bridging sleeves.

The Goss Sunday Vpak 3000 press is commerically available in web widths of up to 1,905mm, while a narrower web width is
available in the form of the Sunday Vpak 500 press, which starts from 521mm.

These presses are targeted at firms producing folding cartons, flexible packaging, preprint and label applications. With maximum print speeds up to 457m/min, the manufacturer highlights the platform's key features as the aformentioned quick-change sleeve adapter technology for fast, cost-effective size changes, as well as advanced offset inking, tension and control systems across the board.

Looking beyond European boundaries, it is worth drawing attention to US-based packaging and label producer Precision Press, which recently became the world's first firm to invest in the Sunday Vpak press.

The new press was specifed for flexible packaging applications, featuring Sunday Vpak 500 web offset printing units, and an in-line flexo and coating unit. It also includes a Goss closed-loop colour, registration and inspection system equipped for both UV and EB curing. The Minnesota firm is using the machine to print on a raft of film substrates, and cited the offset print quality and quick change sleeve technology as deciding factors in its investment.

"We have made a deliberate decision to do something different," says Precision Press president Lee Timmerman. "There is a lot of untapped potential for web offset in the packaging arena, and we're excited about the new print quality, productivity and efficiency benefits the Goss press technology will bring to our customers."

Space for innovation While there are manufacturers of the standing of Goss firmly established in the web offset field, the market has far from plateaued.DG Press Machines, which is a sister company of DG Press Services, has recently taken the lid off a new web offset press concept
for package printers. Currently known as Thallo, the technology is the culmination of more than a decade's experience in the manufacture and refurbishment of sleeve offset presses.

The concept will not be shown officially until the Labelexpo exhibition in Brussels later this year, but Peter Kloppers, director at the business, is already eyeing strong growth for the Thallo platform, which will be showcased as a concept printing deck during the Belgian event.

"Many years of continuous dialogue between us and end-users has initiated the need for an improved concept," he adds. "There is an incredible potential for offset in packaging, but a limited amount of feasible offerings on the market."

The Thallo press will be available in 520mm, 850mm and 1,050mm web widths, although the company stresses that these are not yet set in stone.

It will be available in cut-offs ranging between 406mm and 762mm and will be also be stepless, meaning that any size between these measuresments is actually possible.

According to the manufacturer, the design allows users to "alter the repeat length of the press" by being able to change the plate and blanket sleeves, without needing to completely change the unit or cassette.

In addition, the press utilises standard offset printing plates, which is claimed to offer a more efficient and cost-effective alternative to flexo or gravure processes.

Because the press uses regular offset plates, the prepress process is the same as for conventional litho printing, and therefore
said to be considerably quicker and cheaper than flexo or gravure.

Richard Miedema, sales engineer at DG Press Machines, stresses that the technology will benefit from the diverse experience of the firm's founding members.

"We bring what no other competitor currently can bring to the market," he says. "Our people are the pioneers of the use of sleeves in offset and have extensive knowledge and experience in this field, collected during the Drent Goebel era.

"After Drent Goebel closed," he adds, "we started with a small group of 10 key engineers, having grown to 40 - most of them former Drent Goebel employees - in just three years."

DG Press Machines, which anticipates pricing to be up to 20% lower than compatable technology, will showcase the machine at
Labelexpo and will take orders for production in 2015.

Also on the exhibitors list for the September Labelexpo show is French manufacturer Codimag. The firm has enjoyed solid sales of its intermittent-feed presses since launching them more than five years ago. Available in two web widths, the Viva 340 and Viva 420 presses have more than 30 installations across Europe. Pierre Panel, export sales engineer at Codimag, says the technology appeals to converters requiring the production of cost-effective shorter runs that flexo can't offer.

"Digital and flexo are important aspects of packaging printing, but offset has an integral part to play," he says.

"We are using our presence at Labelexpo to allow visitors to have their jobs printed live at the show. This way, we can demonstrate the incredibly fast set-up times, high print quality and limited prepress that makes the Viva platform an attractive proposition," he adds.