Digital adds a special touch

Since the last Drupa, digital technology has come on apace, enabling applications that used to be in the domain of long-run litho work to be rolled out cost-effectively for shorter run and personalised jobs.

Have you got a personalised mailer that you’d like to recreate the texture of an orange skin on? A gloss-marked certificate that requires only a limited run of 40 copies? That’s no problem, because between them, these digital printers are now capable of performing those applications and many more...

• UNUSUAL INK COLOURS  HP INDIGO RANGE 

What effects can be created?
New applications for digital presses were opened up when HP launched a white ink at the end of 2010. This white liquid toner can be used either for printing on coloured substrates, or to allow double-sided images on transparent substrates, with the white ‘ink’ being used to separate each layer of coloured image.

The HP Indigo range can also support a wider gamut of colours than was previously available on a digital press, with an IndiChrome system that uses an orange and violet toner. This, says HP, allows digital printers to match colours out of the gamut with CYMK. Or, if the client is very sensitive about colour matching and the shade is still not in the gamut, special spot colours can be created in a special ink-mixing facility in Israel.

Who uses these applications?
The white ink is typically popular with those printers catering for clients creating high-impact products, says HP India country manager, A Appadurai. “Greetings cards, postcards and signage are often created using coloured substrates,” he says, “and direct mail has moved towards more personalised, high impact stuff with more unusual colours and substrates becoming more of a focus.”

White ink is also sometimes applied to white substrate as another way of creating high-impact direct mail pieces, reports Appadurai. The application also comes into its own, he says, where a metallic effect is desired. “You can’t put a magnetic or metallic ink through a digital press,” he explains, “but you can use a metallic substrate or foil and use the white to block out the background areas.”

Spot colours and Indichrome are used by printers with customers who are very strict about colour matching, but also by those catering for the fine art market, where the possibility of using mid- and quarter-tone greys means high-impact black and white images can be printed.

How are they applied?
The white inks and spot inks are applied in the same way as the CYMK. It is because inks used with the HP Indigo range use liquid toner technology instead of dry toner, says Appadurai, that this has been enabled.

What are the advantages of doing this on a digital rather than litho press?
“If you’re running a short-run campaign, as you would for a personalised mailer, you can’t run this cost-effectively on litho,” says Appadurai. “So if you want to mix white ink or brand-matching with short-run or bespoke campaigns, digital is the best option – especially when the Indigo’s quality is similar to a litho press.”

• SECURITY APPLICATIONS  XEROX iGEN4 AND DOCUCOLOR

What effects can be created?
A hologram like effect (Glossmark) for security (that can be detected without the aid of UV or infrared light) can be applied to any printed product on the Xerox iGen4. Certain parts of the ticket are given a glossy sheen – an effect which, according to Xerox, cannot be counterfeited. “It’s a visual differential when you catch it in the light,” explains Xerox India head, graphic communications business, Pankaj Kalra.

“It’s changing the way in which your eye looks at the printed image.”
The Xerox printers can also create fluorescent markings only visible in UV light, security text only visible in infrared light and micro text which appears as jagged lines to the naked eye, but can be checked and authenticated under a magnifying glass.

Who uses these applications?
The glossmark watermark, fluorescent and infrared text can all be used for a wide range of security applications, says Kalra, including tickets, vouchers, certificates, examination papers etc.

“Because it’s digital printing, multiple security features can be applied even to a single document and hence applicable to very low print volumes,” says Kalra. “So someone might have a week’s worth of events at a club and want to give out tickets where each one has a different security code. Or the watermark may in some cases be required for a product where you only want to send out a certain amount, and you need to track and trace them.”

The micro text application is designed for printers who produce documents containing personal information such as birth certificates and personal identification papers, explains Kalra.
 
How are they applied?
The application of microscopic text as small as 1/100th of an inch high has been facilitated by overall improvements in digital printing technology, specifically the constantly-improving image quality of printers, says Xerox.

The gloss, UV and infrared marks don’t require any extra inks, says Kalra, and are instead created using patented technology to lay down the CYMK inks at different angles to the rest of the printed product. “The beauty of the system is in the fact that you use just a standard machine, standard toners and standard papers,” says Kalra. “So it is part of the printing process itself and all you require is an additional piece of software.”

What are the advantages of performing appli-cations on a digital rather than litho press?
While litho can apply a wide range of security marks – such as holograms and fluorescent marks – through plate preparation, die-cutting or using additional coating units, the advantage of using a digital process is that you can apply multiple security features on small run lengths and each item can be personalised with variable data.

This comes into its own particularly with micro text. While litho presses can apply the words ‘authorised signature’ to personal cheques to prevent fraud by relying on the fact that such microscopic print is very difficult to counterfeit, digital printers can print someone’s name and address in the signature line. Or, for company and government cheques, the specific amount paid can be printed in microscopic font. This can then be checked against the normal-sized information to safeguard against fraud.

• 3D INK, GLOSSING AND SECURITY APPLICATIONS   KODAK NEXPRESS

What effects can be created?
The Nexpress’ three-dimensional ink can be used to create tactile effects, such as reptile skin. The Kodak system can also apply a gloss coating (this is a fluorescent red security coating only visible when UV light is shone on it) and magnetic ink character recognition (MICR) inks for banking documents and cheques where there is need for ink that can be recognised by banking machines.

Who uses these applications?
The three-dimensional inks have proved popular with a wide range of clients, says Kodak India vice president sales – digital print – EPS, who explains that the effect can be used to add impact to any direct mail piece or other marketing material.

“At any point throughout the past 20 years, if you went to a printer and showed them a sample, you might think that it was sharp and of high quality, but you would have seen the same thing 100 times,” says Ramani. “With a three-dimensional ink, you put that in front of them and you are looking at something totally new, different and exciting.” The gloss coating is typically used, says Ramani, to add a gloss finish to posters and paperback book covers.

How are they applied?
The 3D effect is created by first working with Adobe Illustrator, Photoshop or InDesign and selecting the colour that has the most tonal separation to use as an extra layer. This colour layer would be printed using the Nexpress’ fifth unit in a clear ink over the top of the colour. The ink expands when it is put through the fuser in the normal course of printing, due to the larger particle sizes of the dimensional inks.

The Nexpress’ fifth unit can also expand the press’ colour gamut and apply the gloss coating or MICR ink.

What are the advantages of doing this on a digital rather than litho press?
Previously, a 3D effect could only be created by thermography, a system separate to the printing process, says Ramani. “You would put down a special ink and heat it up in an oven-like machine, so it raised off the card,” he says. “This was popular for business cards in the 70s and 80s, but tended to only be used for stationery because the special ink was expensive. Because it’s a separate process, it is also more time-consuming.”

Using a Nexpress to coat books is becoming an increasingly sought-after option, due to shorter run lengths, adds Ramani. “The book market today can go from 5,000 to one, so in this situation there’s no comparison because it’ll be so much cheaper and quicker to use a digital printer.”

• GLOSS FINISHING  SCODIX DIGITAL EMBOSSING PRESS

What effects can be created?
The Scodix UK digital embossing press is a standalone system that applies a clear gloss finish to printed products after they have been through either a digital or litho press. “It produces breakthrough Scodix SENSE printing experience that makes a lasting impression and brings new, high quality look and tangible dimension to printed graphic communications,“ says TP Jain, managing director of Monotech Systems (Indian representative for Scodix) “It has the power to stir the senses with its creations that produce an eye-catching memorable experience.”

The gloss can be built up to 99 Gloss units – the highest available for printed material, polymer height upto 70 micron – 10 times higher than selective varnish and variable density capabilities-1% to 100% to create 3D and embossed effects.
 
Who uses these applications?
People are using the finish, says Jain, for a variety of commercial work, from leaflets to business cards and other stationery products, consumer products like invitations, greeting cards, photo albums and industrial applications like packaging of high-end products. The finish gives printers who produce these kinds of materials differentiation against competitors, he says.

How is it applied?
The gloss is a clear ink that can be laid down in any pattern or font. This is much simpler and cheaper, says Jain, than the process through which such an effect would historically have been created, where the pieces of print would have to be sent to a trade finisher to be masked-up and then coated. “You can have different levels of gloss ink within the same page,” says Jain, “so that opens up all sorts of creative possibilities. Now awareness is increasing that this type of effect is more readily-available, designers and creative people are starting to think completely differently when designing.”
 
What are the advantages of doing this on a digital rather than a litho press?
“Although you can use the finish for litho printed work, the fact that it is a digital process really comes into its own in a large amount of promotional work where you have some personalisation,” reports Jain. “The reason for this is that it can apply the gloss to be in-keeping with any variable data that is then printed on a digital press.”

 

Litho Manufacturers' speak

Peter Rego, general manager, sales at Heidelberg India
“Heidelberg presses have an ability to produce special effects using aqueous and UV coating devices. These include spot coating and drip-off effect which are created by printing an aqueous varnish coating over matt varnish coating, so that the gloss drips away from the matt areas. Such applications are not yet possible on digital. Also inline die-cutting at high speeds, cast and cure technology along with structuring or knurling inline etc, can so far be achieved only with offset vis-à-vis digital.

Again, security and rainbow printing needs high precision which only offset can cater to. Duo-press technology to print on plastic and non-absorbent substrates for high-end labels at high speeds along with inline foiling also falls in the offset domain and it is true for packaging too. Then offset again comes into picture when there are metallic inks and substrates like Magnacoat plus fluorescent inks used for signs. There’s no denying that digital presses have their own strengths and are improving in features and productivity.

For example, digital presses can now print on heavier substrates and have also gained speed. However, there is quite some catching up yet to be done with simple facts that offset presses are capable of handling papers as thin as the onion skin to 550gsm and heavyweight board with speeds upto 18,000sph. At the end of the day, both technologies have their own niche markets; digital is good for short runs of even upto 100 sheets and variable printing, while offset is good for short as well as long runs, with an advantage of handling myriad complex print applications.”

Aditya Surana, managing director, Indo Polygraph Machinery (representative for KBA sheetfed presses in India) 
“What offset can’t do is personalisation, and that’s the differentiator when choosing a technology between digital and litho, certainly not short-run jobs. Today, offset can run short-run jobs cost-effectively. Printing is not merely service, it’s manufacturing business now, hence automation, performance and output is the name of the game. Offset machines are now capable of run lengths below 250 copies, some even as low as 100.

As for special applications, these can today be done using offset too. It can create a range of effects with coatings, with standard range of inks and coatings. It can reproduce and hold minute details in very small printed areas of the image. Digital has certainly come of age, but that’s also true of offset, and we can bet that even today offset is the best for colour matching and vibrancy with the ability to match a much wider colour gamut.  Our customers inform us that offset still has higher print quality.”

Sangam Khanna, director (Komori division), Insight Communication 
“Variable data printing is something that offset has not been able to achieve. But rest of the issues like short-runs and very short-runs have been made possible, for example, by using Komori offset-on-demand. A customer can walk-in with a CD or a job, have his cup of coffee and by the time he’s finished, the job will be ready for delivery.

With the same technology, you can also do all the application of value added printing. A press fitted with HUV and coater can do all the special effects on paper, plastic and foil board with just about all kinds of special effects.”