The new nonwovens

June 12th, 2017 / By: / Featured

Caption: Teijin’s Unisel nonwoven uses a proprietary process to achieve an ultra-fine multi-layered and stretch -expanding material that can be printed. Material and weight are both minimized, which is also good for the environment. Photo: Marie O’Mahony

Improvements in performance include more eco-friendly materials and processes.

The global market for nonwovens is expected to grow from its 2015 level of $2.9 billion to $8 billion by 2022, according to Stratistics Market Research Consulting, specialists in global cross-sector market research. Existing market sectors such as health, hygiene and automotive applications are expanding, and others are being added, with much of it driven by advances in technology and the need for more sustainable product. Exhibitors at this year’s TechTextil in Frankfurt reflected this trend, shown in the use of specialized fibers, paired with new construction techniques for novel and more sustainable structures.

Specialized fiber

Japan’s Teijin Frontier Co. Ltd. has introduced an ultrafine, polyester nanofiber. The company believes that its “Nanofront” is the first 700-nanometer fiber produced using a special sea/Island composite spinning technology that promises to overcome the consistent quality issues that can be associated with many mass-produced nanofibers.

These new nanofibers are incorporated into a “sea” alkaline substrate that is then dissolved to leave just the fibers, creating the maximum surface area with the lightest quantity of material with a suede-like hand. It’s used in the company’s NanoFiber air pollution mask and also their Nano Skin Care Face Mask Sheet that holds the cosmetic product well, minimizing loss of product in use.

Carbon fibers have been used to fulfill the need for high strength in industrial, automotive, sports and other applications. Many of these utilize knit, weave or composite structures. Researchers at the Institut fur Textiltechnik und Lehrstuhl fur Textilmaschinenbau (ITA), RWTH Aachen University (Aachen, Germany) have developed a fabrication process to produce semi-finished nonwovens that incorporate carbon fiber.

PolyTube is a glass fiber-reinforced plastic tube that includes layers of recycled carbon fiber (rCF) on the inside wall. The intention is to produce a GFP tube with electrical functionality using the conductivity of the rCF fibers. In this way, static charge can be discharged to realize a cost-efficient heating of the tube and to detect any defects that may be within the wall of the pipe. The main source of carbon fiber textile waste comes from the liquid composite moulding (LCM) process, where up to 40 percent of waste can accrue, say researchers at the Fraunhofer Institute in Germany. The savings on this process is both economic and environmental.

Novel construction

Developments in manufacturing technologies mean that we are now seeing the production of nonwovens in more refined structures. Researchers at ITA in Aachen have developed a hybrid nonwoven that allows for the individual design of a nonwoven reinforcement structure. To do this, a PA6 sheet with carbon fiber is combined with an airlaid nonwoven resulting in a reinforced organo sheet. The nonwoven can be used to produce a 3D reinforcement structure for use in composites. It offers good optical and haptic qualities and is ideally suited as a functional surface material in lightweight construction. The application of heat-generating and EM shielding for transport and design is further expected by the developers.

One of the issues with 3D nonwoven structures is the danger of reduced strength and stability where stitching or bonding occurs. This can be caused by compression in the case of stitching, or heat deformation where thermoplastic fibers are bonded together.

Teijin Frontier has applied their expertise in novel performance staple fibers and high-level nonwoven production to create a 3D nonwoven called Decolay. The large surface area offers efficient filtration brought about by good collection and a low-pressure loss. It offers a touch that is soft and smooth, making it ideal for sanitary goods and beauty products. Teijin has applied for Japanese patents, and the product is currently under development for mass production. It is expected to be on the market by 2018.

Sustainable approaches

Teijin’s Decolay nonwoven allows for a 3D nonwoven structure that brings maximum surface cover with uniform strength throughout. Photo: Marie O’Mahony

Nonwovens, like all textile sectors, have been moving steadily towards more sustainable production processes. Initiatives such as the use of recycled fibers and yarns have been around for some time, but solutions are now emerging from the nonwoven textile machinery manufacturers.

An example of this is the German company Dilo Groupe, which is developing equipment that offers customer savings on raw materials and energy use—both of which are good for the environment and the balance sheet. The company produces equipment that focuses on the mechanical production of web formation and consolidation that uses low energy in comparison with non-mechanical processes. Their machines are capable of processing natural, bioplastic and biodegradable fibers.

The Dilo – Isomation Process offers reduced fiber consumption with an even web mass. The objective is to stabilize the quality of the material, preventing the elongation of fibers without slowing down the speed of production. Minimizing the amount of fiber in the material is achieved by reducing drafts, planar compression and the use of the doubling effect.

The common perception of nonwovens as a disposable material has not served the industry well from the point of view of sustainability. Technical Absorbents, a U.K. company, have developed a nonwoven fabric that is washable. The material is based on the company’s super-absorbent fiber (SAF). When this material is used as a core within protective outer materials, it can be laundered and dried with minimal loss of absorbency.

At present, this development is aimed at apparel and hygiene markets, but the company sees potential applications in many other areas that it is eager to explore. As Technical Absorbents’ commercial director Paul Rushton explains, “Innovation is at the heart of everything we do as a company.”

The RadiciGoup in Italy believe it necessary to control the whole production process in order to be fully sustainable. Today RadiciGroup is the only European industrial group that has the capability to control the production process in its entirety, from chemicals to synthetic fibers and engineering plastics, including end-of-life recycling,” according to vice president Maurizio Radici.

Innovations include the recycling of post-consumer waste (PET bottles) with a UNI 11505- certified traceability for their r-Radyarn and r-Starlight materials. The aim of the group is to produce technical textiles that offer high-performance, common resistance, durability, comfort and light weight, all with inherent sustainability to meet the criteria for the Circular Economy.

These are undoubtedly exciting times for the nonwovens industry as companies large and small strive to be innovative, while achieving economic and environmental efficiencies.

Marie O’Mahony is professor of Digital Futures at Ontario College of Art and Design (OCAD) University, Toronto. She is the author of several books on advanced and smart textiles, published by Thames and Hudson, and she is a member of the Canadian Smart Textile and Wearables Innovation Alliance (CSTWIA).

Laundry and care of materials has become an increasingly important factor from an environmental point of view. This development from Technical Absorbants addresses the need for cleaning and extending the product life of nonwovens. Video: Technical Absorbants.