Using Enabling Technologies to Make a Better Nonwoven
Attention nonwovens brand owners, product managers and salespeople: take the nonwoven product that you make, market or sell, hold it up, and examine it. Think carefully about how all of its parts - be they unique fibers, layers, finishes, elastics or adhesives - work together to provide the end-user, the consumer, with a valuable, trustworthy product. That is precisely what raw materials suppliers must do everyday.
This article offers nonwovens brand owners important tips on using enabling technologies to improve the performance, functionality and marketability of nonwovens. It is designed, in part, to help you think as a raw-materials supplier would. We ask you to take this leap because it will help you to:
1) Enhance your existing product offerings and innovate new ones;
2) Better understand the benefits and features of nonwovens products;
3) Better market and sell your nonwoven materials and brands.
These goals are particularly important as nonwovens applications begin to compete more closely with those of traditional textiles. We have to continue to work together to make a better, affordable product with greater performance and functionality.
Tip #1: Do not underestimate the value of adhesivesIn the nonwovens industry, hot-melt adhesives have a public image problem to overcome. Because very little of the adhesive is visible to the product end user, and, as their purpose is largely internal to the end product, adhesives are often viewed as commodity ingredients by nonwoven goods producers. In reality, the picture is quite different: there is real value in an adhesive's ability to bond dissimilar substrates under a range of process conditions - and to keep them together afterwards. Imagine a diaper that falls apart on a child as it comes into contact with baby lotion, or a car mat that softens and becomes sticky in the excessive heat of the noonday sun. Adhesives formulated with the right tackifier resins and polymers can help overcome these challenges.
New tackifiers and polymers for adhesives are set to revolutionize the production, structure, look and disposability of nonwoven products. Formulated into low-viscosity adhesives, they enable adhesives to be applied at lower application temperatures than before. This enables the use of thinner, softer substrates, helping nonwoven goods producers to develop innovative designs with improved customer appeal. Using tackifiers with better thermal stability improves the appearance of and reduces odor in the final product, reassuring the end user of its sterility and integrity.
Novel polymers for adhesives are leading to the development of readily disposable items such as diapers, adult incontinence and feminine hygiene products. These polymers are engineered to hold together when in contact with bodily fluids but to break apart in tap water. In an age where convenient, environmentally friendly products are key selling points, adhesives matter.
Tip #2: Understand the function and value of polymersPolymers are the basic building blocks of a nonwoven, affecting the key properties brand owners seek in a finished nonwoven. They can impart softness, absorption, elasticity, strength, elongation, drapability, moldability and rigidity to a nonwoven product. Yet the choice of polymer for a nonwoven is generally removed from the brand owner. In most cases, a brand owner goes to a roll goods supplier for a sheet of pre-fabricated nonwoven material and handles the assembly of the complete product in-house.
In medical gowns and drapes, for example, the choice of polymer in the base structure can provide several benefits to the end user. A low-melt viscosity polymer will create a nonwoven with finer denier fibers, offering enhanced water and viral resistance to medical nonwovens. At the same time, the breathability of these fibers helps to keep them comfortable. Certain polyesters and co-polyesters are engineered to better handle hospital sterilization processes, such as gamma radiation. Others may more readily accept certain dyes, which will enable them to maintain their color through launderings and exposure to UV lights. The right polymer will enable the product to last and look better longer.
In choosing a polymer, brand owners must also consider polymer adaptability and suitability to specific processing technologies, such as staple fibers, spun-bond and melt-blown polymer fabrics. Raw materials suppliers like Eastman can work with fiber and roll goods manufacturers and brand owners to select materials that balance production and performance needs, such as processibility and ease-of-assembly with fabric softness, temperature-resistance, and sterility.
Tip #3: Distinguish yourself with fiber and surface enhancementsThe addition of additives in polymer or topical treatments can be a cost-effective means to enhance the performance of nonwovens without a significant investment in new equipment.
The addition of an antimicrobial to a polymer fiber, fiber blend or nonwoven can help to retard odor, maintaining fabric freshness. Such treatments offer huge marketable benefits to the makers of bed linens, worker uniforms and sportswear. By retarding body odor, antimicrobials keep fabrics smelling fresher for longer.
Nonwoven wipes treated with cellulose esters also have enhanced product delivery capabilities. This benefit helps end-users get more from each wipe, offering a real sense of value to end users. For example, a medical wipe treated with cellulose esters can better transfer a sterilizing cleaner from the wipe to a surface. Less of the cleaner stays in the wipe, and more is transferred to a surface, actually improving the ability of a single surface wipe to do its job. Imagine how important that benefit is in a hospital setting where patient safety is paramount. Similarly, facial wipes treated with cellulose esters can ensure that more skincare product reaches a consumer's skin in each wipe, reducing product waste.
Advancements in bicomponent fiber technologies can further extend the benefits of nonwovens substrates. The latest in these technologies actually increases the surface area of the unique fibers in a nonwoven, enabling a household wipe, for example, to pick up more dust in a single wipe. This is a powerful selling tool in the competitive market of household cleaning goods.
Tip #4: Think in terms of layersThe use of multi-layered materials in a single nonwoven item can provide significant moisture management attributes. Such an approach can wick moisture away from the skin in one layer, absorb it in another layer, and, if need be, release moisture into the air though a third layer. For example, consumers demand a thin diaper that is dry next to a baby's skin but that also retains moisture to prevent messy leaking. In athletic and active wear, the ability to manage moisture is crucial. Athletic socks, head bands, ski wear and running gear can all be enhanced by new nonwoven fabrics that pull perspiration away from the skin and then slowly release that moisture into the air to keep skin dry and comfortable.
While polymer selection can help provide these performance attributes, varying the extrusion techniques of nonwovens within a single item can also help. In SMS fabrics, a single layer of material extruded using melt-blown ("M") methods is sandwiched between two spun-bond ("S") layers of material. The spun-bond layers provide strength and durability and encase a more fragile, but tighter-woven, melt-blow layer.
SMS fabrics are ideal for medical and surgical gowns and masks, because the spun-bond support layer holds the item together and prevents splattering blood from absorbing into the gown or mask, while the melt-blown layer, engineered for smaller pores sizes, actually traps viral germs. Such an item might help prevent the spread of viruses in an emergency or operating room, freeing up staff to treat patients while potentially reducing the spread of disease.
The challenge for raw-materials suppliers and nonwovens producers is to engineer and combine these materials in the most efficient, cost-effective manner. Today, researchers are actively working on developing extrusion systems that will enable the varying layers of a nonwoven to be produced simultaneously in-line, leading to significant increases in production speed and making these moisture management technologies more affordable.
Tip #5: Add value by combining multiple polymer, adhesive and film technologiesOver the past ten years, the North American nonwovens industry has gone through considerable consolidation, which has led to the commoditization of many nonwoven goods. Commoditization in the industry has opened the door for inventive producers and brandowners to innovate in order to gain a competitive advantage. Engineered, multi-layer composite fabrics can help nonwovens producers and brandowners de-commoditize their product offerings.
Think of it this way: The addition of each value-added feature to a nonwoven product increases the return on investment in that product. The more value-added features that a company includes in its nonwovens, the more that company can distinguish its products from the competition, and the more product it will sell.
Following are a few examples.
- In athletic wear, as discussed previously in this article, the padding on a baseball cap can be engineered to manage perspiration. In addition, polymer fibers in the padding can be extruded so as to add acoustical properties to dampen or sharpen sound.
- A lightweight ski jacket can be made with enhanced insulating properties while offering absorption properties and remaining breathable. These are serious value-adds to downhill skiers, who may perspire coming down the mountain but otherwise sit cold in wet skiwear riding the ski-lift back up to the summit.
- This philosophy can even be applied to something as simple as a household sponge. A rougher, scrubbing side of a sponge can be adhered to a softer layer extruded for better breathabililty, then the entire sponge can be treated with an antimicrobial to prevent food odors from lingering in the sponge. The sponge scrubs better and lasts longer.
With an increasing complexity of needs, the best raw materials suppliers continue to work to ensure that their materials are compatible and stable under an array of manufacturing processes and end-use applications. They work closely with nonwovens producers and brand owners from product development, manufacture, and assembly to ensure that the materials that are used can be manufactured affordably and efficiently, thus enabling brand owners to deliver the best-performing product possible to the marketplace.
For more information on nonwovens, contact Eastman Chemical Co., http://www.eastman.com .
SIDEBAR: Nonwovens TechnologiesEastman Chemical Co.'s line of nonwoven technologies has applications in industries including automotive, medical, home furnishings, personal care, filtration, and industrial cleaning wipes and solvents. The company produces extruded polyesters and copolyesters for nonwoven fabrics that are used in surface preparation wipes, air and water filtration systems, uniforms, and protective masks. Its portfolio of polymers, resins, finishes and flurochemical extenders delivers improved hand and color fastness, abrasion resistance, and oil and water repellency. They provide increased strength and rigidity for nonwoven applications.
- Performance chemicals ensure structural integrity and appearance. Eastman's self-crosslinking acrylics are used in chemical-bonded nonwoven fabric formation, as well as in finishing and printing applications for durable nonwoven products. Crosslinkable and self-crosslinking binder polymers have significantly improved the performance and uses of nonwoven materials, enabling them to withstand washing and dry cleaning. Crosslinkable acrylics and acrylic/polyester hybrids provide unique properties for disposable nonwovens formulated without formaldehyde and other chemical additives. Eastman's polyester resins give strength, rigidity and moldability to nonwoven fabrics, and its Eastobrite Optical Brighteners keep them white and bright.
- Cellulose esters ensure proper film formation. Eastman's cellulose esters, including Eastman CA (cellulose acetate), Eastman CAB (cellulose acetate butyrate), and Eastman CTA (cellulose triacetate), are critical components in the manufacture of nonwovens - from fiber and nonwoven production to enhancement, converting and finishing. Compatible with a range of resins, these esters (including CMCAB, the industry standard waterborne cellulose ester) aid in proper film formation and binding of coatings and inks to nonwoven products. In so doing, they enhance the appearance and appeal of nonwoven products.
- Polymers and resins are the building blocks of nonwovens adhesives. With a portfolio of polymers and resin tackifiers, Eastman makes the essential building blocks for nonwovens adhesives. Eastman's hydrogenated hydrocarbon resins, such as Regalite and Eastotac, help make adhesives stick. They are characterized by low odor, good solubility, excellent heat stability and low color. Amorphous polyolefins (APOs), sold under the trade name Eastoflex, are used as base polymers in formulating hot-melt and pressure-sensitive adhesives. The materials offer consistent quality, low odor and compatibility with a variety of elastomers, polymers, and tackifying resins. Eastman AQ Polymers are specially formulated to be water-dispersible, offering improved disposability and recyclability to nonwoven products.
- Solvents enhance the cleaning capability of industrial, commercial and household wipes. The industrial fabrication of metal parts, aircraft, automobiles and medical equipment requires a cleaning process before, during, and after assembly. With a portfolio that includes Eastman MPK, Eastman Methyl Acetate and Eastman EEP Solvent, Eastman offers an array of products for industrial cleaning and surface preparation to meet the performance and environmental requirements of manufacturers. The company also supplies solvents for wipes suitable in commercial and household applications. Coupling solvents, such as Eastman EB, which is found almost universally in all-purpose cleaners, attach oily solids from hard surfaces to wipes, but are miscible in water.
From diapers to sneakers, from filters to wipes, Eastman's high-quality products enable the makers of nonwovens to ensure the integrity of their products, reduce production inefficiencies and stay at the forefront of new technologies and processes.