Media Contact: Cynthia Challener

Manufacturers of fibers and textile chemicals are developing new products and processes to enhance the sustainability of textile production

Traditional textile production, which consumes large amounts of energy, water and chemicals, may be environmentally unsustainable, but margins in this industry are slim, and brutal competition does not favor improvements that add cost.

Increasingly, however, both clothing manufacturers and retailers see an advantage in bringing greener products to the consumer, and they are putting pressure on suppliers to adopt more eco-friendly practices.

Impetus for change must come from consumer merchandisers, says Glenn Nedwin, executive vice president of Genencor, a division of Danish foods group Danisco.

"About 54m tonnes of fiber is processed each year, which requires approximately 1m tonnes of dyes and 7m tonnes of other chemicals and accounts for nearly one-third of global water usage and 4.3% of worldwide energy consumption - second only to pulp and paper processing," he notes. "And much of this activity occurs in 50,000 or more small manufacturing plants across Asia."

Growing consumer interest is an important driver, particularly in the European market, according to Dorothy Maxwell, a leading consultant to the Sustainable Clothing Roadmap initiative on behalf of the UK's Department for Environment, Food and Rural Affairs (Defra).

"To maintain and grow their customer base of this new generation of environmental and ethically aware consumers, retailers in particular are pushing sustainability requirements back down their global supply chains," she observes

Given its scale and fragmentation, the textile industry will adopt more sustainable processes slowly. But transformation is underway throughout the supply chain.

For example, growing numbers of international firms are offering clothing made from organic cotton, grown without petrochemical-based fertilizers and pesticides. However, this represents only about 0.3% of industry demand, and even processing of the organic cotton continues to present concerns.

The environmental credentials of alternatives need greater clarity to ensure that they are in fact more sustainable options across their supply chains, Maxwell says.

Other "greener" alternatives include organic wool, bamboo, hemp, soybean fiber, biopolymers and polyester recycled from used clothing.

Japanese chemical company Teijin leads the effort in this last category. Its ECO CIRCLE environmentally friendly closed-loop recycling system chemically converts used polyester products into new polyester raw materials. The reclaimed polyester is of a purity comparable to virgin fibers, but the system reduces energy consumption by 84% and carbon dioxide (CO2) emissions by 77%, the company says. Approximately 120 organizations worldwide participate in the program.

Recycled polyester products from Teijin include ECOPET polyester fiber made from recycled polyethylene terephthalate (PET) bottles, ECO CIRCLE FIBERS and recycled polyester fiber recreated from used clothing and uniforms. Recently, the company began encouraging the use of polyester-based apparel accessories in order to increase the ease of recyclability of garments.

Rayon, which is produced from wood pulp, seems to be an attractive option, but the manufacturing process still consumes large quantities of energy and creates significant amounts of wood waste. Introduced in the early 1990s, Lyocell, sold under the trade name Tencel, is also made from wood fiber (harvested from tree farms). It is biodegradable and recyclable, and the production process is more sustainable and includes recovery of most chemicals.

Other innovative synthetic fibers have been introduced by US-based DuPont and NatureWorks, as well as Teijin. Sorona, from DuPont, contains 37% by weight of renewably sourced ingredients derived from agricultural feedstocks. Production of Sorona requires 30% less energy and reduces greenhouse gas emissions by 63%, according to the company.

Ingeo fiber, from NatureWorks, the first man-made fiber from 100% annually renewable plant sugars, is supplied into apparel, home textile, and increasingly the personal care & hygiene (nonwovens) markets. According to NatureWorks' director of fibers and nonwovens, Robert Green, the production of 2.2lb (1kg) of Ingeo entails the production of 2.2lb of CO2. By contrast, he says, the production of 1kg of synthetic fiber is accompanied by the release of several kilograms of CO2.

"Ingeo's eco-pedigree, combined with its compelling performance properties and appeal, makes it a very interesting proposition for the textile and nonwovens industry," he says.

Biofront, a heat-resistant bio-derived plastic, was introduced by Teijin in 2007. This stereocomplex polylactic acid has a melting point of 210°C (410°F), making it possible for Biofront fabrics to be ironed. The company has found applications in the apparel and automotive interior sectors, according to Hideshi Kurihara, general manager of the high-performance biomaterials project at Teijin.

Chemicals are used not only to produce fibers, but also for scouring, bleaching, desizing, softening, mercerization, dyeing, printing and finishing textiles. They include specialty materials such as biocides, flame retardants, water repellants, stain blockers and antistatic agents, as well as more common ingredients including surfactants, waxes, starch and oxidizing agents.

Flame retardants, particularly poly­brominated diphenyl ethers (PBDEs), have become a concern.

"While most manufacturers in the US have halted production of many PBDEs, there still must be an effort to prevent future release of these chemicals into the environment," says principal author Kimani Kimbrough. Because there are large quantities of PBDEs found in consumer products, disposal of these products must be accomplished in such a way as to not further contaminate the environment, he adds.

New alternatives include Teijin's Super Extar, which chemically bonds to polyester fiber, preventing release to the environment. Even when burned, no cyan or halogenated toxic gases are generated, according to the company.

Formidable Formaldehyde

Formaldehyde content on textiles has also become an issue in the US and Europe. One response is BASF's formaldehyde-free Helizarin pigment printing system, which ensures "zero add-on" of formaldehyde during production and needs no further treatment, according to Janardhanan Ramanujalu, head of global business management for textile chemicals at German major BASF.

Helizarin is part of a comprehensive BASF initiative to address consumer safety, resource conservation and climate change within the textile industry. Other elements include two new fluorocarbon finishing systems for stain repellency and release. Both contain C6-based Lurotex fluorocarbon finish and Perapret booster for enhanced performance. With C6 technology, perfluorooctanoic acid (PFOA) levels are reduced to below the detectable limit using state-of-the-art analytical methods.

"Innovative textile chemicals and processing technologies that contribute to eco-efficient processes for textile mills can save costs and help reduce the environmental burden," observes Janardhanan. "We are responding to the stronger demand for ecological textiles with such innovative products, but these efforts will require the support of the textile value chain through acceptance of higher priced textile chemicals."

BASF and partners also conducted a project to calculate the carbon footprints of specific articles from empirical data collected during the actual process. Using the company's more "eco-efficient" textile auxiliaries and technologies, its partners were able to reduce overall CO2 emissions during production. The carbon footprint calculation is based on an excerpt from BASF's Eco-efficiency Analysis tool, which is an ISO 14040/14044 methodology.

To improve its performance, the Teijin Group in 2008 developed its Design for Environment (DfE) Guidelines, covering the life cycle of the production process according to six main criteria: energy efficiency, resource conservation, security, environmental friendliness, transparency and environmental impact.

To date, says Takeshi Muraoka, general manager of Teijin's environment, safety and health office, 20 products and one production system have been approved and certified under the DfE recognition system.

Genencor is providing enzyme-based technologies that can replace harsh textile chemicals. One is PrimaGreen EcoWhite, developed and launched in cooperation with Switzerland-based Huntsman Textile Effects, in May. When used in Huntsman's Gentle Power Bleaching system, it can save up to 40% in energy and water use and reduce cotton loss by 50%. Preliminary results indicate that the system reduces the climate-change impact by 25%, according to Nedwin.

"Overall enzyme use in the textile industry stands at just 1%," states Nedwin. "We expect as consumer demand for greener products increases and regulatory pressure rises, the growth potential for these enzyme solutions will be significant."