High speed inkjet papers

Users of the industry’s first high speed inkjet presses found that initial paper options for the technology were somewhat limited. Digital Printer finds out what the latest state of play is.

Paper manufacturers

Ad Sies, sales & business development manager for digital, Crown Van Gelder  

It’s a complicated market. There’s a need for both dye and pigment inks and increasingly a need for one paper to work with all the different inkjet printing machines. The challenge of creating a portfolio that works on all machines and in all market segments is getting bigger and bigger.

Transactional paper is totally different to book paper and to DM paper – the weights, quality requirements and shades are so different. We try to offer a lean development process involving the OEM that builds the machine, the ink manufacturers, and those in the different market segments, such as publishers and printers.

Finishing is another element, because parallel with inkjet you have the integration of print and finishing. If you are going straight into a finishing line at high speed it is very complicated and it makes paper even more important. You cannot just say, let’s make a 180 gsm paper; the calliper and shade of the paper is crucial, the run-ability is crucial. We have all been focusing on the look of the paper, does it look like offset; now it is, is this suitable for book printing?

Quality-wise, we have a range of seven papers and next to the silk range we have created a bright silk with the same feel. Gloss papers are very expensive – almost impossible to produce at the price that the market will pay. It’s not possible for us to copy that for the inkjet market just yet.

The challenges we are addressing at the moment are:

1: Making papers that perform at the price the market expects

2: Proving ROI

3. Drying paper at high speed and going direct to finishing

4: Globalisation – we sell all over the world and distribution is difficult; transactional you can predict; less so with publishing and DM is not predictable at all.

In the future, we will be going to lighter and heavier papers. We need a certain volume to be cost efficient as a mill but the market is shouting for these solutions.

Johannes Klumpp, marketing & sales director, Mondi Uncoated Fine Paper    

The technical challenges revolve around the high-speed processing of ink, i.e. the drying of different inks (dye and pigment) of various OEMs and at the same time retaining colourants on the surface. The more ink is applied the more critical this becomes. Only special grades can cope with the high amount of water based inks and dry them. Uncoated grades with their open structure are a good starting point. Coated offset grades with their closed surface are typically not suitable for inkjet printing.

Drying can be well controlled already. Colour brilliance is increasing. Glossy paper grades are still difficult to make. One big challenge is the difference between what printers are used to in terms of paper haptics and optics, and what they can use with the high-speed inkjet technology. They need to rethink the substrate approach. Inkjet printing should be about how to employ the technology for new ways of communication, and not about replacing one technology (laser, offset) with the other (inkjet). There is no value add in this.

Mondi’s new high speed inkjet portfolio 2.0 features a larger colour gamut, increased opacity, and new grammages of 60, 70 and 230 gsm. We have further developed and optimized the paper manufacturing of the high speed inkjet portfolio. The larger colour gamut in critical colour areas, such as reds, compensates the magenta weakness of current high speed inkjet systems and thereby enables improved accuracy when it comes to logos or reproduction of images. The increased colour gamut also results in a potential ink saving for printers, reducing costs and increasing printers’ competitiveness on the market.

Sappi

Sappi has developed its expertise in digital paper for inkjet printing over many years.  Our Jaz range of digital paper includes three surface options available in a variety of grammages.

Jaz Gloss – true coated paper with an exceptionally smooth gloss surface, ideal for use in commercial printing and magazines. Jaz Silk – a coated digital paper with real silk finish and the look and feel of traditional offset-printing paper Jaz Book – a lower weight digital paper specifically created for full-color book production

Printers can use a true coated digital paper with the look and feel of traditional offset printing paper. Our production technology has been fine-tuned with HP using Colorpro technology, with the result that our digital paper has been completely tailored for the world of high speed inkjet printing.

Sappi has added to its Jaz range over the years to respond to customers’ needs as well as to trends in the market place. It began with Jaz Silk in 2011, Jaz Book at the beginning of last year, and Jaz Gloss towards the end of last year.

Inkjet press manufacturers

Erwin Busselot, marketing director for digital printing, Kodak 

We work very closely with the paper companies and have active relationships with 40 paper mills worldwide, 25 of whom are developing new inkjet treated papers. Another way of co-operating is Kodak’s Diamond certification system. We test their papers on our devices and give them a rating on a 5-Diamond scale, so customers will know if a paper is good for a certain application. It’s important if you’re doing just mono books – you don’t necessarily need all the highest ratings.

It’s about fit for purpose. With a mono text book, most of the papers offer no problem. If you are going to coated papers it depends a bit on the speed you want to print, and the drying capacity of the printing system. The Proper 6000 press can print at high speeds on gloss and silk and has a better drying system, based on infrared, to deal with higher ink coverages. Humidity evacuation is also another major step forward to make inkjet more viable.

There were problems with colour on uncoated, as the ink would sink very deep into the paper, and it would look a bit faded. That was an issue for many of the vendors but there were always ways around it, such as by choosing different paper, or printing slower. We all learned that you’ve got to dry as quickly as possible, because that keeps the ink pigments at the surface of the paper, and that meant drying much closer to the printing heads than ever before. We have pre-coat now, and that’s a simple solution to that.

Currently, we are trying to work with the paper mills to find ways to make papers geographically available everywhere. It looks like a logistics exercise more than anything else but if we achieve that it will be a very nice gift to the market.

Gianluigi Rankin, worldwide product marketing manager for HP Web Press Media Technologies

My team works very closely with paper manufacturers to develop papers that are optimised for the HP inkjet web press, and many paper companies use our Colorpro technology to get the best quality from the press.

If you think back to 2009, we had difficulties finding paper companies that would work with us; they did not know where the market would go. Now they are seeing that high speed digital inkjet is growing and they want to develop something. There is still a lot of work to do and many alternative papers that could be introduced to the market. 

The big wish we get is that printers want to pay offset prices for inkjet paper, and we are not there yet. The volumes are really a drop in the ocean, so there are not the same economies of scale.

For uncoated paper, we have a bonding agent, but there have been issues on the coated side, so about two months ago we introduced a priming agent, supplied as a flood coat to the paper, which makes just about any offset paper printable on the HP web press. We started with matt for publishing papers and we plan to expand it to other applications. At the moment it’s a near-line application, a coater with an unwinder and rewinder, but you could also put that inline, right before the printing stage. 

In Europe, silk is the most popular coated paper, but there is also a need for gloss, and that’s more difficult to develop. There is very little available today, but I expect we will see some change in the next couple of months.

Paper merchant

Sham Ahmed, digital sales manager, Antalis                       

This market traditionally is served directly by the mills – there are only 125 big inkjet installations in Europe. As the printing technology improves, printers are moving away from transactional  – which left no room for a merchant to operate in – to short run DM work and different markets where buying a container of paper is not going to be cost effective for them. As a merchant, we have the facilities to stock products on a call-off basis, and we’re also looking into the possibility of doing one tonne orders, giving customers flexibility to try new avenues into markets.

We stock products from Mondi, Mitsubishi HiTec Paper, and Sappi, and we have a silk coated paper, Cocoon Jet Silk, that’s new in the market, which will give excellent ink quality with the speed and efficiency of a web press. The challenge we have is to convince customers that this product gives them an edge in the market and that they can buy a two or one tonne minimum.