4^th ANNUAL CONFERENCE on the
DIGITAL PRINTING OF TEXTILES

November 13-15 2000, Atlanta, Georgia
Report by David J. Tyler

According to a recent survey, about 3000 digital printers are installed throughout the world. These are mostly used for sampling fabrics, for photo-shoots and for making personalised or otherwise customised products. These printers are generally described as "entry level" with a throughput of up to 8 m² per hour. "Advanced machines" are being launched by the technology manufacturers, with throughputs of about 20-30 m³ per hour. The key question considered at the conference was whether these new machines mark the start of a new phase of expansion for digital printing of textiles. A selection of papers presented at the Atlanta conference are reviewed below.

Digital colour printing of textiles: challenges & rewards
Web site: http://www.it-strategies.com/home.html

Mark Handley, Managing Partner of IT Strategies, provided an overview of this "emerging market". He commented that it is not clear where the market for digital printing is going: it is seeking to produce in traditional markets, but its importance is that it has the potential to create new markets and new value streams. The global market for printed textiles has remained in the range 16-20 billion metres for the past two decades. During this time, however, batch sizes have declined significantly. Rotary printing run lengths in 1989 averaged about 4500 metres whereas in 1997 the figure was 2600 metres. Despite this reduction, advanced digital machines are not approaching the speeds required to impact on the main screen print market. Handley reviewed the different application areas (exiting and potential) and came up with a forecast of worldwide hardware units reaching over 6000 in 2001 and over 12000 in 2003. The largest application areas were perceived to be personalised and customised products.

Can digital printing fit the bill?
Web site: http://www.digitalprintingsystems.com/

Digital Printing Systems is a US company that has collaborated with print head suppliers, ink suppliers and a software supplier to develop printers for mass customisation. DPS points out that although screen printing has numerous advantages, the technology is much less attractive with small batches. The drawbacks were identified as:

Digital printing addresses all these drawbacks. A specific comparison was drawn with printing speed. A rotary print speed of 30 metres per minute, together with a down time of 60%, yields a net speed of 12 metres/min. This should be compared with the current offering of digital printing of 1-2 metres/min.

DPS claim that they are the first company to bring "high speed" textile digital printing machinery to the market. Limp fabrics may be glued to paper before printing. A post-printing heating unit allows the immediate fixing of pigment inks. The illustration is of the DPS85T machine. It uses the Jemtex multideflection continuous head and achieves a resolution of 600 dpi.

Printing Head Developments

The heart of digital printing is the printing head, and developments in this area are expensive. Manufacturers of printing heads have multi-million dollar R&D budgets. This research has been directed primarily to paper printing, where it has been profitable. One of the suppliers of textile printing heads presented at the conference: Jemtex Ink Jet Printing Ltd., an Israeli company. (The web site is under construction: http://www.inter.net.il/~jemtex/)

Jemtex drew an analogy with paper printing: digital printing of paper achieves 10% of printing speeds and ink costs are 3 times as much per square metre. Extending this to textiles, where the comparison is with screen printing, the target production rate is 200 m²/hr and the ink cost is $3/m². The Company has developed a printing head that is continuous (as opposed to the drop spot approach). There are various continuous techniques:

• a binary drop path (undeflected on to the fabric or non-printing drops are deflected into a catching reservoir);
• a multi-deflection drop path (where the non-printing drops enter the catching reservoir);
• a modified multi-deflection drop path, where the non-printing drops are deflected to the catching reservoir).

This illustration shows a multi-deflection drop path. Drops emerge from the nozzle and are charged by passing between the charge electrodes. They then pass through the deflection plates and are guided to their specific locations. Non-printing drops are caught by a device positioned just above the substrate. The merit of the multi-deflection continuous process is that it speeds up the printing process. The constraint is that it may not be possible to use standard ink colours, and that ink pastes of specific shades have to be prepared to manufacture specific prints.

Representatives from other printing head suppliers (Aprion Digital Ltd., Stork Screens America Inc., and Hewlett Packard) were at the conference, but did not present.

Ink Jet Printing of Textiles
Du Pont’s perspective on the use of digital techniques in household textiles

DuPont Ink Jet Inks are suppliers of inks to the digital printing industry. DuPont have concluded that ink jet printing will become the preferred method of production printing of textiles. They consider that print batches will continue to decline and that, with enhancements to digital printing technologies, the costs will converge. DuPont has identified bedding (and household textiles) as a key sector where changes are opportune. However, this is just the start of developing solutions.

DuPont have found that a high viscosity paste should be used with household textiles. This is to ensure that there are sufficient cross-links developed in the heat-fixation process to deliver the required standards of dye-fastness and durability.

The Company has worked with a digital printer manufacturer to develop a wide-width, piezo jet printer with a built-in post-print heat fixation system. The associated colourware can read textile CAD files and work with textile colours. The results of this collaboration are to be demonstrated at Heimtextil, January 13-18 2001.

High Performance Piezo Ink Jet for Printing Textiles
Howard Baldwin, Spectra Inc.

Inks for digital printing appears to be a very competitive area, and where suppliers of inks have to be at the forefront of developments. There were many representatives of ink suppliers at the conference, all of whom have developed inks for the paper printing markets and are looking at ways of diversifying into textiles. Baldwin’s talk was an overview of the technological issues and pointing out the need for system integrators to bring everything together to achieve commercial success. A separate report is in preparation to summarise these technical issues.

Textile & Apparel Market Dynamics
Alison Grudier Hardy, FabriCAD, http://www.fabriCAD.com/
James R. Whittington, Trendwatch, http://www.trendwatch.com/

Trendwatch aims to gather statistical data about markets based on creativity, printing, packaging, publishing, Internet design and development, textiles and apparel. Their research methodology is to use postal questionnaires (with response rates being 17%-30%). This presentation was a preliminary overview of their first look at the US Textile & Apparel industry, based on 200 responses. Their target response total is 550-800.

The companies responding were primarily manufacturing within the US and were generally positive about the future. The dominant CAD software used was Adobe Photoshop and Adobe Illustrator. Gerber and Lectra products together were owned by only 12% of the respondents. Colour printing resources, for product development, were not plentiful. Very few companies were utilising digital printing.

The predictions made were that the textile and apparel markets will follow the pattern of technology implementation shown by other graphic arts markets. There will be an increasing use of digital technologies. There is enormous potential for system integrators to work with the sector and for training agencies to support the move towards digital technologies.

Digital Printing Exercise results and insights to expanding digital textile printing
Katy Chapman, CADmium Services

In June 2000, companies were invited to participate in the digital textile printing seminar to be held August 21, 2000 at the CADExpo in New York. This seminar was part of the Computer Integrated Textile Design Association (CITDA) Symposium. The goal for this seminar was to build awareness and give designers and CAD users information and tools to help them sort out the myriad options in digital textile printing. Companies were invited to participate as a way of building awareness of their product offerings.

Companies were told: "Designers want "apple to apples" comparisons. To best represent CITDA's members and target audience we have selected one apparel image and two home fashions images. The colors in these images are identified by Pantone Textile System colors or LAB values". [abridged]

When returning printed swatches, companies were asked to supply the following information: Ink(s), Media, Pre-treatment, Post treatment Printer hardware, Software, RIP, Est. cost per square meter, Other notes.

The thinking behind this exercise was that the industry finds it difficult to handle the digital printing technologies. There are so many choices, there is a need to understand the various capabilities, and the technology is changing fast. Print quality is influenced by many factors: the image file, the printer used and its various sub-systems, the media, the software and the printing environment.

A panel of experts was invited to assess the offerings of 11 companies. Their brief was summarised in the table overleaf.

An example of one of the images is illustrated below:

The exercise was deemed highly instructive. There were many significant differences in the various offerings and there were surprising results too (such as the excellent visual appearance of 4-colour printing compared with 12-colour printing). The lessons learned are summarised in the table below.

Whilst this exercise was certainly of interest, it did seem to me to convey something of a blinkered vision approach to the new technologies. The main focus of interest was in getting samples and reducing lead times for product development. This is certainly the main current use of DTP, but designers should perhaps be alert to the potential of the technologies to deliver innovative designs to the market place.

What changes can digital printing bring to the Textile Industry?
Thomas Poetz, 3P Inkjet Textiles AG.
Web site: http://www.3p-inktextiles.com/

3P is a company that has developed coatings for textile materials that are applied prior to digital printing. They also provide paper backings for limp and easily-deformable materials. The key thought developed in this presentation was "mass customisation of textiles". Target application areas are:

• Soft signage/graphic arts market
• Household textiles market
• Fashion textiles market

Each of these has particular requirements. For example, the soft signage area needs fire retardant materials (for indoor use) and UV resistance, waterproof and weatherproof (for outdoor use). Further, the household textiles area requires good dyefastness, durability and fire retardant finishes.

Thomas Poetz made it clear at the outset that he does not see digital printing as a replacement technology for screen printing, etc. If mass customisation is the key word, then we need to look for new business models: there are new market opportunities, new customers, and new distribution concepts. The problem he has identified is that all of the existing users appear to be locked into the current paradigm. They have technical expertise and some experience of the current business models, but they appear not to have a vision for the new business models that are needed to take DPT forward.

The recommendation brought to the Conference was that a major educational initiative is urgently needed. This would bring together textile knowledge (substrates, pre- and post-treatments, textile design), digital printing expertise (DP technology, ink and colour technology, colour management) and marketing knowledge (local, national and international markets, supply chain issues relevant to meeting consumer needs in those markets, an ability to explore different business models).

If educational initiatives were successful, the vision was presented of:

• The Textile Industry will become a much more attractive working environment for people
• High profit textile businesses will be re-located nearer to the place of consumption
• The image of the Industry will be changed: a high-tech digital image!

Without wishing to align myself too closely to the "mass customisation" goal, there are many areas here of mutual interest. NWACW has contacted Thomas Poetz with a view to exploring collaboration in education in Europe.

Further reports related to Digital Printing of Textiles are planned. If you would like to receive them, please contact David Tyler, North West Advanced Clothing Web.

Tel: 0161-247-2636
Fax: 0161-247-6354
email: d.tyler@mmu.ac.uk
Return to main menu: http://www.advancedclothing.org/

Prepared November 2000