After going through a slump in the late 1990s, textile printing has been experiencing a revival. Improvements in printing equipment and colorants, especially pigmented systems, have helped to generate double-digit growth levels in some textile printing segments.
As a result, competition among producers of inks for textiles has been intensifying in Europe. Long-established suppliers of textile inks, some of whom trace their history back to the manufacturing of dyes for fabrics, are now having to contend with ink makers whose are mainly active in the graphics market.
There has been a similar trend among European printers who have found there are now closer links than before between graphics and textile printing. Screen printing, mainly using the flatbed and rotary systems, continues to dominate textile printing, but other processes, such as offset and inkjet, are penetrating the sector.
Increased use of heat transfer printing, in which the image or design is first printed on paper, is providing new opportunities for printers in textiles.
European printers are printing decorative images on heat transfer paper, which is then shipped to the Far East for application by Asian textile producers.
With heat transfer printing, textile producers claim that they can employ a wide range of colors and achieve higher resolution.
“There is rising demand for offset printing in textiles because of the popularity of transfer printing,” explained Daniel Neira, European marketing manager for textiles at Sun Chemical Screen. “Transfer printing with offset is cheap because it reduces storage costs and can be used for short runs. Large volume transfer printing work is now being shifted to low cost areas like Eastern Europe.”
However, the growth in transfer printing has not only been bolstering offset but also inkjet printing. This is especially the case with the dye-sublimation process, in which dyes on the transfer substrate are heated to such an extent that they vaporize and then penetrate the fibers in the fabric. Sublimation provides rich colors while it is also suitable for short runs.
Inkjet has also benefited from the greater use of textiles in wide format printing in Europe, especially for advertising and promotional purposes.
In fact, the wide format market is typical of both the current opportunities and also the technological challenges for ink makers because of the variety of fabric materials being used in the sector. Ink producers face similar technical difficulties across the whole textile printing market.
Textiles have a broad range of natural and synthetic fibers which differ in terms of physicochemical properties, weight, thickness, yarn size and ink absorbency. At the same time there are differences in needs for color, wash and lightfastness and crock or abrasion resistance.
Cotton accounts for approximately half of printed textile substrates and polyester, cotton/polyester blends and viscose much of the rest. Among the many materials with relatively small shares of the sector are polyamide, polyacrylic, wood and silk. Recent improvements in the color absorbency of polypropylene have raised the possibility of printing on a polymer which is the most extensively used petrochemical-based fiber.
In addition, most textile substrates require treatments both before and after printing, mainly to ensure the inks adhere properly to the fibers.
Another challenge is the safety standards which are starting to be imposed on producers in the supply chain by retail groups in the European clothes market.
Also throughout the chain, much more importance is being given to the need to reduce waste and pollution. In textile printing, a major priority is the introduction of processes which reduce consumption of water and energy.
The UK retail company Marks & Spencer, which is a trend setter in the creation of standards, has recently introduced a list of minimum environmental and chemical standards for textile production, including printing.
The code bans, for example, solvent-based binder systems for pigment inks in favor of aqueous-based binders. It also prohibits the use of certain dyes, organic solvents and plasticizers like phthaltes in inks. Panel prints in children’s wear are required to be PVC-free.
H&M, the Swedish-based international retail company, has been combining with other global apparel retailers and brand owners to draw up water quality guidelines to reduce pollution by wastewater discharges by textile mill and printers.
For some ink producers, the imposition of standards by retailers is seen as an opportunity, especially if they require technological innovations. Retailers will often recommend to their textile suppliers the use of specific inks.
Sun Chemical has launched a range of phthalate-free textile inks which instead use thermoplastic resins to provide a soft yet elastic film on the printed surface. The inks can be used on most fabrics including cotton, wool, acetate, polyester and cotton/polyester blends.
“We believe our inks have superior wash fastness to other phthalate-free inks while they are also suitable for transfer printing, because of their good heat stability,” said Mr. Neira. “We have been working with Marks & Spencer to ensure that the inks are approved for use by their suppliers.”
Following its takeover last year of Ciba Specialty Chemicals’ textile effects operation, Huntsman Corporation is giving greater prominence to social and environmental responsibility in the way it runs the business. It has just launched a range of screen printing inks with a new type of reactive dye for printing on fibers like cotton and viscose.
The new ink considerably reduces the amount of water required in the printing process by increasing the proportion of dyes which are fixed to be fabric by a steaming process. The unfixed residue dyes are then washed off, usually with the aid of large quantities of water.
“With this new reactive dye, which has an innovative chemistry, we can reduce the amount of water used in the printing process by 30 to 40 percent,” says Ian Burnell, product manager for the inks, which will initially be marketed under the Cibacron PH brand name.
“Normally the fixation level on reactive dyes is around 65 to 75 percent,” Mr. Burnell added. “We are now able to raise it to around 90 percent so that the wash-off rate is considerably smaller.”
Cibacron PH should be particularly helpful for textile mills and printers in Europe which are having to deal with European Union legislation on water pollution, which severely restricts the amount of dyes of which can be discharged in effluent.
“A lot of textile production has moved out of Europe into Asia but hopefully a lot of European textile printers will still be able to operate here despite the amount of legislation on water pollution,” said Mr. Burnell. “Cibacron PH may make it easier for them to comply with the legislation.”
The Rise of Inkjet
The complexities of inks required for textile printing has deterred some ink makers from moving into the sector, which still tends to be dominated by producers who have been in the market for a long time. But while the expertise of these established players is mainly in inks for conventional textile screen printing, they have also been expanding into inks for new printing processes.
BASF, for example, divested its dyes operation several years ago and sold its business in graphic printing inks two years ago. However, it has retained its textile printing business, where it remains a strong force in pigment inks.
Through its Helizarin brand, it is a leading supplier of pigment concentrates for screen printing in textiles. But it has also extended the Helizarin label into pigmented inks in the inkjet sector in textiles, where BASF also sells a sublimation ink.
Although inkjet printing was first applied in textiles 10 years ago, it still has only 1 to 2 percent share of the total textile printing market. Still, in certain niches, it has a strong presence. It is used extensively for printing of samples. A large proportion of silk screen printers in textiles in Europe are thought to use inkjet printing equipment. It has a much bigger share than the market as a whole in T-shirt printing.
“The closer a textile printer is to the graphics sector the more likely he is to be using inkjet,” said Mike Freche, inkjet business development manager at BASF.
One of the main problems facing inkjet operators in textiles is that i
n comparison to printing of papers, fabrics require substantially more ink because of the greater absorbency of fibers. Textile screen printing also has a wide color gamut derived from the use of 12 to 15 colors against which 4-color inkjet has difficulties competing, particularly in relation to costs.
Nonetheless, in terms of quality, inkjet has been catching up. New inkjet printing machines have been developed which makes printing on fabrics easier. Improvements in inks have reduced the need for pre- and post-treatment of fabrics and also widened the color gamut, helping to make inkjet more cost effective.
BASF has introduced special binder systems to solve some of difficulties with the adhesion of the inks to fibers, a drawback to the inkjet process.
“We have made a lot of progress with our pigment inkjet inks and we are now able to use them on 95 percent of textiles,” said Mr. Freche. “There are still problems with a material like wool whose uneven surface can cause complications with printhead nozzles.”
Inkjet is thought unlikely to make major inroads into textile printing until textile production has become much more customized than it is at present. In a long-term review of the European clothing sector drawn up last year, Eurotex, the textile industry’s trade association, envisioned a move to the personalization of apparel products.
Instead of the current system of basing demand on guesstimates, clothes production would consist of made-to-order operations using equipment like 3D body scanners, Internet communications and small-scale localized manufacturing plants. Inkjet would fit much better in that sort of infrastructure.