Natural Fibers Win Laurels

June 14, 2005

lured by a variety of benefits, nonwovens continue to go natural in many applications

As nonwovens continue their mass entry into new markets, the uses for natural fibers are still expanding. With benefits including comfort, moisture absorption and retention and renewability, natural fibers have proven they are an ideal fit for a variety of nonwovens applications.

Although natural fibers such as jute, hemp, flax and sisal offer environmental friendliness and strength, cotton is by far the most popular natural fiber, thanks to its versatility in a wide range of products. Cotton is ideal for nonwovens requiring absorbency, such as hygiene. “The softness, absorbency and wipe-dry performance of cotton makes it a great choice for nonwovens,” said Chuck Allen, technical accounts manager of bleached cotton supplier BBA Nonwovens Natural Fibers Group, Simpsonville, SC. “There is a consumer preference for products containing cotton.”

Nonwovens that use cotton fibers include feminine hygiene items, industrial and medical wipes, needlepunched batting, mattress pads and filtration media as well as a variety of niche segments within these markets. “Cotton is a good fiber to use in liquid filtration applications because of its unique ribbon shape and range of fiber diameters that are well suited for depth filtration applications,” explained George Hargrove, vice president of sales and marketing at bleached cotton supplier, Barnhardt Manufacturing Company, Charlotte, NC.

Mr. Hargrove added that bleached cotton is ideal for medical and wipes applications or other end use products where consumers expect a pure product. Barnhardt operates a Continuous Bleaching Line, which enables it to offer pure white cotton fibers to these market segments. Fibers on this line offer the purity of cotton with the uniformity traditionally found in synthetic fibers. “Barnhardt’s Continuous Bleaching Line provides our customers with more open and less broken fibers, which leads to less linting,” Mr. Hargrove explained. “This is particularly valuable for spunlace producers, which have traditionally used synthetic fibers. Wipes are undoubtedly a perfect end use for cotton because of its biodegradability.”

Biodegradability has gained increasing importance as growing environmental concerns continue to prevail globally. One of the ways manufacturers are responding to this increased environmental awareness is by reverting back to natural fibers for nonwovens.

Sustaining Natural Fibers
The expansion of global wipes market has helped boost natural fibers’ popularity throughout Asia and Europe, mainly because of increased ecological awareness in these areas. Asia has experienced a growth in cotton spunlaced wipes, whereas Europe is experiencing increases in the use of cotton nonwovens because of the boom in the cosmetic wipes market.

“In the past few years, there has been a push by consumers to move toward natural fibers that offer the same performance as synthetics,” said Marcel Dartee, global platform leader for nonwovens at Cargill Dow, Minnetonka, MN. “The biggest push for natural fibers is currently coming from the Asia-Pacific region, where concerns for the Earth are the highest. This is followed closely behind by the European market.”

Cargill Dow has responded to consumer preference for products containing natural fibers by spending the past decade, and more than $750 million, researching and developing its new Ingeo fiber. The company’s business is now equally split between packaging and Ingeo fibers. Ingeo, which was launched globally in January, can be derived from any form of annually renewable starch resources or fermentable sugars, but Cargill Dow is currently only making it from corn. Ingeo is reportedly replacing polyethylene in spunlaced wipes. Meanwhile, in the automotive and construction areas, Ingeo is being used as a binder fiber. Other areas where Ingeo is gaining ground include the baby, cosmetic and household wipes markets as well as in high loft waddings.

“Sustainability is a growing concern for the nonwovens industry, as well as for consumers,” explained Cargill Dow’s Mr. Dartee. “The trend toward natural fibers has shown growth during the past few years, and we believe it will continue to grow. There are natural fibers available today that offer the same comfort and performance of synthetics, making it easier for companies to make the switch.”

Ingeo, which can biodegrade in approximately 50 days in industrial compost or standard waste disposal systems, offers wicking, soft hand, low melting point characteristics and is naturally flame retardant. When compared to fibers made from petroleum-based materials, such as polypropylene, Ingeo reduces greenhouse gas emissions and the use of fossil fuels.

Ingeo’s benefits have not gone unnoticed. To date, Cargill Dow has secured more than 100 global partners who have signed on to develop and market products under the Ingeo brand. The most recent partners are Toray Industries, Osaka, Japan, Far Eastern Textiles, Taipai, Taiwan and The Radici Group, Bergamo, Italy. All of these companies have agreed to sell Ingeo branded products in markets such as bedding, carpeting and furniture, to accredited downstream participants.

Cargill Dow’s Ingeo fiber, which is derived from corn, is replacing polyethylene in spunlaced wipes.

Ingeo’s success has served as an example of how important continued product development and innovation are to the natural fibers market; however, keeping natural fibers on a fast track in new nonwovens markets will not be the easiest task for suppliers. One of the largest hurdles fiber suppliers are facing is raw material price increases. This has significantly impacted both the natural and synthetic fiber markets. With higher oil and energy costs and changing cultivation conditions driving the prices of raw materials up, many fiber suppliers have had no choice but to increase the prices of their products.

“There has been a sharp spike in fiber prices during the last quarter of 2002 and the first quarter of 2003,” explained BBA’s Mr. Allen. “The forecast is for fiber prices to increase slightly throughout the rest of this year. Having said this, it must be noted that the early 2002 cotton fiber prices were at their lowest in 30 years.

These higher prices will most likely prevent significant growth for natural fibers in North America in 2003. Despite this, fiber suppliers are reportedly developing new products that, once commercialized, will greatly impact the natural fibers market.

Fiber Innovation Prevails
In an effort to expand natural fibers’ presence in nonwovens, fiber suppliers are blending natural and synthetic fibers, which gives the fiber higher strength and length. When compared with other materials, fibers such as cotton can then be applied in applications that require more durable and high strength materials. Among these are the automotive and construction markets.

“Blending cotton with low-melt synthetic fibers, such as polypropylene or polyethylene can produce thermal bonded fabrics, both high loft and point bonded,” explained BBA’s Mr. Allen. “This trend could increase as fabric demands require properties of both cotton and synthetic fibers also increase. The properties of each are often complementary. For example, the absorbency of cotton is combined with the strength of a synthetic fiber.”

Barnhardt Manufacturing produces bleached cotton fibers for carded, needled, chemical bonded, spunlaced and thermal bonded nonwovens.

Fiber combinations, coupled with technological advancements, will continue to tailor natural fibers for specific applications. For example, in the case of a thermal bonded product, manufacturers can add or subtract cotton to adjust the fiber’s bonding and melting points.

“Cotton is not thermoplastic, so combining it with polypropylene or polyethylene or any other bicomponent fiber will adjust the temperature needed for fiber bonding for certain applications,” added Mr. Allen. These applications include furniture and bedding, where uniformity and bulk are a necessity. Also emphasizing fiber selection research is Cotton Incorporated, Cary, NC. The company is currently running wipe trial runs to research the impact that fiber selection has on the nonwoven and the final product. Cotton Incorporated is researching the use of cotton in carding and airlaid materials and experimenting with different cotton grades to improve the fiber opening, processing performance, efficiency and the aesthetic value of the nonwoven comprising the fiber.

BBA Nonwovens Natural Fibers Group has seen an increase in cotton in the cosmetic market.

“We are conducting internal research to increase cotton’s presence in North America,” explained Mac McLean, associate director of nonwovens research and implementation at Cotton Incorporated. “This includes strength and absorbency tests and the effects of polyester blends. Wipes have the fastest growing appeal in North America right now and they still continue to generate large profits.”

In addition to stressing the importance of fiber research, manufacturers are also touting the advantages that fiber finishes can bring to the fiber. Any manufacturer who is looking to differentiate its product is aware of how important fiber finishes have become in gaining marketshare. End use products have become more dependent on treatments such as flame retardancy, liquid repellency and antimicrobial finishes. Cotton fibers used in needlepunched products are treated to be more lubricant so the needles can better penetrate the fabric. Meanwhile, fibers used in spunlaced products will often be treated with a slick finish to prevent foaming during water jet entanglement.

“With bleached cotton, fiber finishes will improve lubricity and static resistance, which then improves processing speeds and minimizes fiber breakage and damage during web forming,” BBA’s Mr. Allen explained.

As fiber finishes continue to add value to products, manufacturers are placing more emphasis on ensuring that the chemicals used are safe and lack harmful side effects. At Lahore, Pakistan-based Ihsan Sons, for example, cotton is bleached only with hydrogen peroxide—instead of more harmful chlorine chemicals—according to Sarah Tayyib, marketing manager of Ihsan Sons.

“Finishing treatments are heavily influenced by consumer demands, so the concentration of certain chemicals varies accordingly,” Ms. Tayyib explained. “For example, with the use of bleached cotton for food industry filters, the amount of an antimicrobial treatment is much greater than other finishes.”

Fiber combinations, finishing treatments and implementing ways to derive natural fibers from the Earth’s resources all present manufacturers with increased opportunities to expand the role of natural fibers in nonwovens. Research and marketing studies will also help promote the benefits of natural fibers and help them penetrate newer markets.