This ebook provides helpful information for both nonwoven fabric mills and manufacturers of nonwoven automotive parts and interiors. The information is intended to aid in the selection of moisturerepellent grades that will be most effective for each unique product. Automotive Moisture-Resistant Nonwovens The Advantages of Using Nonwovens for Car Parts and Components 5 A Wide Variety of Automotive Applications 6 Fluoropolymer-Based vs. Silicone-Based Repellents 8 The Challenges of Selecting the Best Repellents for Nonwovens 10 The Importance of Reliable Performance Evaluations 12 Primer of Testing Options for Nonwovens 14 3
The Advantages of Using Nonwovens for Automotive Parts and Interiors There is a growing need to make automobiles faster, lighter and more ecofriendly while keeping costs down. This leaves car manufacturers constantly looking for better ways to improve performance. Nonwoven parts and interiors help reduce vehicle weight and improve their aesthetics, durability, cost-effectiveness and sustainability. Car parts and components like door trim paneling, fuel filters and trunk liners made from nonwoven fabrics weigh less than those made from conventional materials. This helps manufacturers create lighter cars, which drive faster and have better fuel efficiencies. And nonwovens generally cost 10-15% less than traditional materials like woven fabrics and tufted carpets. Manufacturers are able to get lightweight, high-quality fabrics at a low cost. In addition, nonwovens can be used in window covers, door trim and other interior components for sound absorption. Auto cabins fitted with nonwoven fabrics are quieter and absorb exterior noise better than traditional textiles. Nonwovens can also offer superior durability when treated to repel liquids and oils from everyday spills and leaks. To effectively guard against these fluids, automotive parts are fabricated from nonwoven fabrics that are coated with repelling agents as rolled goods. 4 5
A Wide Variety of Automotive Applications Today, over 40 automotive parts are made from coated nonwoven materials. Nonwovens are easy to handle during assembly and can be tailored to fit a wide range of functions. They are also 15-30% lighter than traditional materials, making vehicles up to four pounds lighter. And if a car were to use nonwoven parts in all its possible applications, less CO 2 would be released, and the vehicle s overall impact on the environment would be reduced by 30%. Because of these advantages, nonwovens are extensively used in the automotive industry. Furthermore, when nonwoven automotive parts and components are coated with repellents, they repel water, oil and other liquids and release stains better. This makes them far more durable. Automotive Applications Backing for seat covers Oil, fuel, air and other filters Car mats Trunk liners and Covering material floor coverings for sun visors Door trim panel Window frames carpeting and Speaker covers padding Benefits of Repellent Nonwoven Fabrics for Automotive Products Components like fuel tanks and mufflers wrapped in repellent-coated nonwoven fabrics exhibit lower noise and good thermal insulation. Under-the-hood parts like oil filters and cover slip sheets perform better and last longer when they repel moisture. Automotive interior products like floor mats, seating fabrics and door trim padding repel fluids and release stains quickly. 6 7
Fluoropolymer-Based vs. Silicone-Based Repellents Silicone repellents can also be used on nonwoven fabrics. They usually consist of polydimethylsiloxanes and are sometimes functionalized with alkyl groups to increase their water repellency. Like fluoropolymer-based repellents, silicone-based repellents have low surface energy. Since the surface energy of the fabrics on which they are applied is lower than the surface tension of water, fluids like blood can t get into the fabric fibers. Silicone repellents effectively repel water, but they offer little to no oil and solvent repellency. Also, they do not have good stain release qualities, and they lack durability unless reactive functional groups are incorporated. Fluorochemicals have even lower surface energy than silicones, so they have superior repellency with water, oil and solvents. Also, the carbon fluorine bond is more stable, which increases the performance and durability of fluoropolymer-based coatings. Silicone coatings used to be preferred by manufacturers because they were more environmentally friendly, and they are still considered the more eco-friendly option. However, today s fluorochemicals use C6 technology and no longer contain PFOAs, so they are also environmentally friendly. SILICONE REPELLENTS FLUOROCHEMICAL REPELLENTS Surface energy Low Very low Cost Lower Higher Water repellency Good Very good Oil/solvent repellency Poor Good Durability Poor Good Loading requirement High Low 8 9
The Challenges of Selecting the Best Repellents for Nonwovens Most manufacturers specify repellent coatings for disposable nonwovens so they can repel liquids, release stains easier, or both. However, selecting To resolve this problem,formulators incorporate monomers with hydrophilic characteristics into the fluoropolymer, but this lowers dynamic water repellency. the best fluorochemical grade is challenging because repellency and Suppliers of chemical repellents, stain release are competing properties. like AGC, work hand in hand with manufacturers and mills to figure out Fluorochemicals aid stain release by coating the fibers of the fabric so the stain can t hold on to the fibers. But this strong water repellency becomes an issue when trying to remove stains that are already set in the fabric fibers. To remove a stain, water and detergent must be able to enter the fabric to surround the stain. Highly water-repellent surfaces prevent this from happening. which grade is best for their specific application. For example, we set up the fabric treatment process in the lab so we can treat fabrics using the same conditions as our customers. We typically use a size press equipped with roller pressure and speed adjustments. We also dry fabrics the same way as the mills, using a tentor drying oven with two-stage temperature controls and adjustable dwell time. Reproducing a customer s processes with their fabric samples lets us recommend the optimal treatment conditions, which takes the guesswork out the manufacturing process. 10 11
The Importance of Reliable Performance Evaluations It is important to remember that the reliability of performance evaluations is just as important as the results of those evaluations. That s why our lab gets as much information about customers recipes as possible, including reagents, quantities, order of addition, temperatures, wet pickup, etc. We also look at several other factors to assess the overall finishing process such as run rates, foaming problems, pad-bath stability and polymer buildup on fabric. This allows us to identify pitfalls and communicate important process information to our customers before problems occur. It s the best way to avoid unexpected problems during commercial production. For example, consider foaming issues. Foaming is rarely a problem during testing because the fabrics are run slowly and methodically. But things might be dramatically different in actual use when the mills run fabrics through as fast as possible. If the formulations are evaluated ahead of time for foam production, the mill would know if the formula will foam and become a problem with fast run rates. Knowing things like the likelihood of a formulation to produce foam, the amount of foam, the stability of the foam, and the impact of the foam on production helps mills determine whether or not foaming will affect their production, which prevents unexpected production shutdowns. AGC s lab uses industry standard test methods and data validation so we can provide customers with reliable product recommendations. 12 13
Primer of Testing Options for Nonwovens Numerous tests can be conducted to help mills and manufacturers select the best repellent product for each nonwoven project. Coatings can affect product quality and performance, so understanding the latest technologies available is well worth the effort. Knowing your options requires due diligence. Many mills have established relationships with one repellent supplier and are not aware of the latest technologies, techniques and testing services that can improve their product quality. As a leading supplier of repellents, AGC Chemicals Americas has the laboratory resources and specialists to conduct these tests for customers. For example, at AGC s testing lab, nonwoven fabric mills can test their specific fabrics with varying grades of AsahiGuard repellents. Performance testing for nonwoven fabrics includes testing for water/oil repellency, hydrostatic pressure, surface resistivity, static decay and stain release. 14 15
Water/Oil Repellency Test Measures how well the fabric repels water and oil. Three drops of the IPA/water solutions or test oils are placed on the nonwoven fabric. The fabric passes the test if no wetting is observed after five minutes. As you go up the test scale, the surface tension of the water and oil tests decreases. The lower the surface tension of the liquid applied, the lower the surface energy of the coating must be to repel it. Hydrostatic Pressure Test Measures the force (kpa, cm of water or inches of water) and time required to force a liquid, usually water, through a piece of nonwoven fabric. The larger the force and time required to penetrate the fabric, the more resistant the fabric is to that particular liquid. Surface Resistivity Test Measures how much static charge can be applied to a fabric by measuring the electrical resistance of the fabric surface between two concentric rings. Knowing how much charge can build up on the surface of the fabric is important when the nonwoven product will be used around sensitive electronics. Static Decay Test Measures the time it takes for a charge applied to a fabric to dissipate. Again, this charge can affect medical devices. Stain Release Test Measures ability of fabric to release oily stains during laundering. Corn oil and mineral oil are applied to fabric for 60 seconds before washing. Today s automotive nonwovens must be able to withstand the oils and liquids they come in contact with on a daily basis. By understanding the latest repellent technologies and taking a collaborative approach with the supplier, nonwoven fabric mills and manufacturers can be sure they are selecting the best grade for each product. For more information on moisture-resistant nonwovens, visit www.agcchem.com or call 800.424.7833. 16 17
About AGC & AsahiGuard Recognized by the industry for its advanced fluorine chemistry technologies, AGC Chemicals Americas developed AsahiGuard AG-E600, a high-performance, PFOA-free repellent with improved environmental and biological profiles. AsahiGuard has proven safe and effective for use in nonwoven automotive textiles, and poses no danger to humans, animals, materials or the environment. It also meets the most stringent international regulatory requirements. In fact, AsahiGuard is commonly used at the cutting edge of healthcare due to its resistance to alcohol, water and other fluids encountered in the healthcare industry. AGC maintains a corporate vision to Look Beyond and so anticipates new global requirements and creates value for its customers by continuously innovating technologies and improving customer service. AGC Chemicals Americas, Inc. 55 E. Uwchlan Avenue, Suite 201 Exton, PA 19341 USA www.agcchem.com 18