Sometimes things are better off the way nature intended. Nonwovens producers are realizing this more and more as they turn to natural fibers such as cotton, hemp, flax, jute and wood pulp. These fibers offer advantages including biodegradability, absorbency and low cost that synthetic fibers do not. While there are some drawbacks to using natural fibers in roll goods, such as inconsistency and chemical resistance, manufacturers are turning to them more frequently for use in nonwovens.
“There are a lot of things users get from natural fibers that they do not with synthetic fibers,” explained Keith Schonbrun, director of product development for Aldine Technologies, Carlstadt, NJ. “Certainly with synthetic you think of superior durability and strength, which is true and where that is needed you go to a synthetic structure. However, in many cases where you don’t need to over-engineer or over-build a product, the natural fiber can give you strength and durability while at the same time a printable surface, excellent peel strength, clean peeling, good wet strength and very good conformity.”
As a producer of needlepunched products based on natural fibers such as flax, kenaf, hemp, sisal and jute, Procotex Corporation, Dottignies, Belgium, also agreed that natural fibers have a great deal to offer the nonwovens industry. “Some natural fibers have the advantage of being lightweight and strong in comparison to other fibers,” said sales manager Yves Wuyts. Due to these characteristics, the company is finding success for its needlepunched products in automotive interior trim parts, as well as geotextile uses such as road reinforcement and weed blockage.
The White Knight
Perhaps the most well known natural fiber, cotton is constantly upping its marketshare in the nonwovens industry. Not only does cotton have an inherent reputation for cleaness and purity that bodes well with consumers, it also offers many ingrown characteristics that can benefit nonwovens producers. “Cotton fiber is naturally breathable and soft, which is one of the things consumers look for first,” stated Patty Strandberg, manager global product marketing for Cotton Incorporated, Cary, NC. “Great performance, static-free, hypoallergenic, biodegradable, absorbent—these are the kind of attributes that cotton brings to the table.” Cotton Incorporated has used these properties to form the main marketing stance for promoting the use of cotton in nonwoven applications such as baby diapers, wipes and feminine hygiene products.
Cotton supplier Barnhardt Manufacturing, Charlotte, NC, also led some insight into the beneficial properties of cotton through specific applications such as wipes. “The attributes of cotton specifically make it an ideal fiber choice for wipes because it has high absorbency, superior wet strength and the superior ability to wipe dry,” explained vice president sales and marketing George Hargrove, Jr. “In other words, when you’re using a wipe with polyethylene or other synthetic fibers to wipe up water on a table, it just smears. If you take a cotton wipe across the water, it’s gone.”
Lower cost is another plus that cotton and other natural fibers have over synthetics, especially with the recent rise of oil prices. According to Rick Rudisill, vice president of fibers producer Newco Fibre Company, Charlotte, NC, there has been some interest by batting customers to replace foam with cotton due to the recent price increase of foam. For batting applications, Newco supplies desi cotton, which is a fatter fiber cotton grown in India. When used in certain batting products, desi cotton provides more loft because it is a fatter fiber than traditional cotton. Additionally, in other non-critical areas that normally use rayon fiber, some manufacturers are beginning to turn to natural fibers to save money and take advantage of added benefits. “People are willing to look at a different fiber to get different characteristics in the end product in order to be a little unique and a lot of the natural fibers are somewhat cheaper than rayon,” Mr. Rudisill added.
The Naked Truth
While benefits such as improved absorbency and decreased cost are important, manufacturers need to be aware of what natural fibers can do and how to handle them. According to Geofrey Kime, president of fiber supplier Hempline, Delaware, Ontario, Canada, many times nonwovens manufacturers have not received enough education on using natural fibers. As is the case with synthetic fibers, bast or stem fibers such as hemp have different properties depending on the type of fiber and how they were produced. This results in a range of properties from filler to structural fibers that will affect the processing properties in the end products. “This issue has led to the misinformed belief that natural fibers are highly variable, when in fact many of the natural fibers—particularly the structural fibers—can be produced with excellent control over physical characteristics,” Mr. Kime said.
Greg Diacumakos, vice president of operations for needlepunched cotton producer Acme Pad, Baltimore, MD, said this information sometimes leads manufactures to pass over cotton and other natural fibers. “People don’t know that much about cotton in the nonwovens industry when other synthetic fibers are being used. One of the hurdles is just that people don’t go to cotton as one of their first choices.”
Although in some cases natural fibers can be less expensive than synthetics, many nonwovens producers do not know this and think they will be more expensive, according to Bart Morse, business unit manager for cotton supplier BBA Natural Fibers Group, Walpole, MA. “There is a perception that price will vary dramatically and is uncontrollable due to the agricultural basis of cotton,” he explained. “It is controllable and there are many things that can be done to insulate against price changes. It is more manageable than people think.”
This lack of information extends to concerns over the chlorine bleaching of natural fibers as well. “Until 20 years ago, most natural fiber bleaching was done with a chlorinated compound, but today that is not the case,” stated Aldine’s Mr. Schonbrun. “Now most bleaching is done through an oxygenated process where no chlorine compounds are used, so there is no legitimate excuse not to proliferate the use of natural fibers. It is a very acceptable and environmentally sound pulping process.”
The availability of 100% oxygen bleached woodpulp has enabled natural fibers to get back into the ball game. For example, Aldine has already experienced growth in its food and beverage business for tea bag and coffee filter packs in the gourmet natural food marketplace. “All the components that go into a package are scrutinized and the result of bleaching with non-chlorinated compounds has been a big boost to the industry,” Mr. Schonbrun of Aldine said. “I see natural fibers becoming even more prevalent and acceptable and heavily used in the growing tea bag and coffee filter industry.”
At Acme Pad, the company is starting to see more interest in using cotton for oil absorbency pads due to cotton’s environmental advantages. “Natural fibers can be incinerated and they don’t harm the environment once they pick up the oil,” the company’s Mr. Diacumakos explained. “They can be as good as synthetics for absorbency, however, cotton picks up water easier than some synthetics and you want to pick up more oil than water. That’s the only drawback.”
In addition, Acme Pad has found another niche opportunity for its natural fiber products on the industrial apparel side as filler for the absorbency of perspiration and padding in hot mill work gloves, which are traditionally lined with a rayon product. “Cotton has a better wicking ability than rayon does,” Mr. Diacumakos added. “As people work in the hot mills their hands will sweat and, if they get too much moisture built up in the glove, it can turn to steam, which can burn them and make it hard to operate. The cotton picks up the perspiration and helps to keep the hands cooler.”
Back To Nature
Another challenge facing natural fibers in their drive to increase marketshare is their reported inconsistency and lack of customization options. While synthetic fibers can be made to fit specific requirements, natural fibers are less flexible. To overcome this problem, Odbeck Industries, St. Paul MN, uses air laid technology for producing its natural fiber products. “There is a lot of diversity with synthetics where you can engineer what you need,” explained Mike Becker, an owner of Odbeck Industries, St. Paul, MN. “With cellulosic fibers, what you see is what you get.” One problem associated with this is the consistency of the fiber length.
Fiber length is also a problem for processing cotton, according to Barnhardt’s Mr. Hargrove. “One of the biggest obstacles is that the fiber length of cotton is what it is. In some cases it’s too long and, in others, it’s too short. This specifically affects processability in the different nonwovens applications and the higher speeds they are after,” he said.
Bowers Fibers, of Charlotte, a supplier of raw cotton, cotton comber and flax to the nonwovens industry for medical and hygiene applications—is currently working on improving consistency, according to David Smoots, sales and marketing.
Adding to these challenges is the fact that not all natural fibers are as strong or chemical resistant as synthetic fibers, such as polyester, rayon and polypropylene.“That’s a barrier because when a customer is asking for a real strong type of media, we have to add synthetic fibers or we have to post-saturate natural fibers with some type of resin to increase strength or chemical resistance,” stated Richard Gray, executive vice president for Knowlton Specialty Papers, Watertown, NY. The company often blends natural fibers such as wood cellulose, cotton, hemp and the grass fiber esparto with synthetic fibers including rayon, polyester and glass microfiber. “God has only made so many natural fibers, so we have to start adding some synthetic fibers to increase our performance,” Mr. Gray added.
Fiber cleanliness is also an issue producers need to address, according to Newco Fibre’s Mr. Rudisill. “Customers are always looking for items that are cleaner, but at the same time they want to buy them cheap, which is kind of like saying ‘take a bath but don’t get wet.’ You have to market the fiber as you produce it and if you produce it in the low end price range, then you don’t clean it up as much because the more you clean it, the more shrinkage you have and your costs go up. The problem is that everybody wants the fiber cleaner, but they want it at as cheap a price as the dirtier stuff, so it’s a catch 22.”
Instead of allowing such entry barriers to get natural fibers down, fiber suppliers and natural fiber roll goods producers are putting the ingrown characteristics of these fibers to good use in new products and market areas. The industrial market in particular seems to be an area where natural fibers are heading and finding growth possibilities. According to Mr. Becker of Odbeck, the need for biodegradability in the filtration and geotextile markets makes them prime areas for natural fiber growth. In the filtration area, the company currently manufactures products for watershed filtration and in the geotextile market, Odbeck produces material for landscaping, erosion control and storm sewer run-off. “Going for niche opportunities has definitely helped us expand our business,” Mr. Becker affirmed. “There are quite a few opportunities out there and I don’t think a lot has been done yet about them.” Odbeck currently works with the University of Wisconsin and the U.S. Forestry Department’s forest products research laboratory to develop new nonwoven products using the natural fibers supplied by the company. One such new product is a substrate for NASA that may eventually be used to cultivate food crops in outer space.
The industrial market is the largest area Aldine is targeting, according to the company’s Mr. Schonbrun. Within this area, Aldine currently has a large representation in the battery separator market as the principal developer of a new abaca-based tissue is used as a separator predominantly in rechargeable batteries for electrical vehicles, lawn mowers and wheelchairs. “The tissue itself is very thin and lightweight and has a very high strength to weight ratio,” Mr. Schonbrun said. “We felt that the basic characteristics of high purity, low lint, high absorbency and resistance to specific chemistries fit the bill for natural fibers. We felt that providing a synthetic was an over-engineered attempt, whereas natural fiber components would be not only suitable but probably the very best application and it worked.”
Polymer Group Inc. (PGI), Dayton, NJ, is also using natural fibers in industrial apparel applications. The company is currently targeting the durable apparel market with its cotton and polyester blend nonwovens product. “In nonwovens engineered substrates, the durable apparel market is a niche market to date,” said market manager Jim Lenox. “This will be changing as consumers begin to feel more comfortable with engineered fabrics. The consumer will understand that engineered substrates are extremely durable and offer comfort attributes that traditional textiles cannot deliver. And as nonwovens begin to penetrate traditional textile applications, the role of natural fibers will become more important.”
Within the industrial segment of the nonwovens industry, the automotive market is fielding a lot of attention from natural fibers suppliers and users. According to Hempline’s Mr. Kime, currently the most common method of composite production with hemp is to blend the fiber with a thermoplastic fiber—usually polypropylene—to form a needlepunched nonwoven that can be heated and molded into such things as car interior parts. In this way, the hemp acts as a replacement for glass fiber and offers good physical properties and straight-forward manufacturing at a cost savings. “We’re able to offer these fibers at very competitive prices compared to some of the other products that are in the market,” Mr. Kime detailed. “Additionally, hemp adds structural properties to the composite and helps to save some money and weight in some of the applications. The rising costs of oil and synthetic fibers will definitely work to our advantage.” Due to its success in the automotive industry, the technology is expanding into the construction and consumer markets as well. “A lot of people are looking for environmentally friendly technologies in construction, so they are looking for different things that can be used in those applications,” he added.
In Europe, the use of natural fiber nonwovens in automotive molded parts is in full swing. According to Procotex’s Mr. Wuyts, about 25,000 tons per year of natural fibers are currently being used in the European car industry, which is forecasted to grow to between 40-70,000 tons per year. To meet the growing demands of the automotive market as well as to improve its position in the market, Procotex has recently licensed a new technology called “Fibroline” to impregnate 100% natural fiber needlepunched nonwovens with powders. “One of the advantages of this technology is that we can deliver pre-impregnated nonwovens to our customers, which means less work for them before they would impregnate the materials with liquid systems that were much dirtier than the dry powder system,” Mr. Wuyts explained. “We also obtain better technical and mechanical results, which allows us to lower the weights of nonwovens.”
Malik Industries, Kennett Square, PA, also sees growth potential for natural fibers in the automotive market. According to president Abdul Malik, in the automotive sound area there are sound absorbing pads being made of flax and binder fibers that may have a flame retardancy treatment if required. Mr. Malik pointed out, however, that the industrial segment of the nonwovens industry is not the only area with potential for natural fibers. The company also sees quilts made of wool or silk fibers as an emerging market area for consumers who are allergic to certain synthetic fibers.
Cotton Incorporated is also looking at non-industrial market areas for growth, according to the company’s Ms. Strandberg. “There is huge potential in the absorbent product area for cotton and Cotton Incorporated realizes this. This is why we have established an initiative for absorbent products. We’re going after the technologies and industry attitudes toward cotton in nonwovens to make a big push toward increasing cotton usage.”
“Wipes are such a growing area that we expect cotton to take off not just in baby wipes, but in all areas including consumer, food service, industrial and medical,” added Mac McLean, manager nonwovens research and implementation for Cotton Incorporated. Speaking of medical, the company is also concentrating on new products for the medical and protective apparel markets. “We’re doing some research with the University of Tennessee for composite fabrics with melt blown and spunbond that have a cotton material laminated to them so you can have the cotton side next to the skin for comfort and breathability and still use the protective aspects of the synthetic fibers.”
Although it’s obvious that natural fibers are beginning to penetrate numerous markets within the nonwovens industry, the success of these inroads varies depending on where the product is being used because each global area differs in its acceptance of natural fibers. For instance, European countries are more willing to try natural fibers because the “Green” movement in Europe is stronger than in other areas of the world. “People in Europe are willing to pay a few cents more for a product knowing it does carry the ‘Green’ label as opposed to the U.S., which is not,” Newco’s Mr. Rudisill said.
Mr. McLean of Cotton Incorporated sees growth in Europe for cotton products evidenced by the launch of a new cosmetic make-up removal pad made from a cotton spunlace material that has taken off in both Europe and Asia.
Within Asia, Mr. Schonbrun of Aldine singled out Japan as an area that is now becoming more involved in natural fibers. “Hydroentangled cotton products are coming from Japan, which is a technology that I don’t think many (if any) American companies will ever try because of the expense,” he illustrated. “The Japanese are excellent at taking an unusual process that was made for polyester and apply it to a natural fiber. The spunlacing of cotton into a binder-free material is probably one of the best applications I’ve ever seen.”
Mr. Hargrove of Barnhardt sees tremendous opportunity for cotton in the Far East due to its large population and tremendous growth in disposable applications. “Natural fibers of all descriptions including cotton are very popular in Asia,” he added. “There is no question about it that those are the preferential fibers in the market.”