From the Sector

The full potential of advanced coating and finishing technologies for the production of technical textiles will be outlined by Monforts specialists which takes place in Atlanta, Georgia, in May.

The company and its US representative PSP Marketing, of Charlotte, North Carolina, will be part of the VDMA German Pavilion at the show, at stand 3231 within the Georgia World Congress Center.

A wide range of technical fabrics is now being successfully created with MontexCoat coating units in comination with Montex stenters, including tents, tarpaulins and awnings, black-out roller blinds and sail cloth, automotive interior fabrics and medical disposables.

Full PVC coatings, pigment dyeing or minimal application surface and low penetration treatments can all be carried out with the extremely versatile system. Solvent coatings in explosion-proof conditions, knife coating, roller coating and screen printing are further options and the MontexCoat has been engineered to enable users to switch quickly from one fabric run to the next without compromising on the economical use of energy or raw materials.

“There has already been terrific interest in the MontexCoat and the range of different techniques it enables and we’re far from exhausting its potential uses,” says Achim Gesser, Monforts Area Sales Manager who will be at the show in Atlanta. “For companies who don’t need such flexibility, the economical coaTTex unit is exclusively dedicated to air knife and knife-over-roller coating.

“At our ATC in Mönchengladbach, Germany, however, a MontexCoat unit has been integrated into a full Montex technical textiles pilot line, on which our customers can run trials of new fabrics and finishing formulations in widths of up to 1.8 metres. This line has been engineered to provide the ultimate in precision coating and finishing in industrial-scale trials.”

To fully demonstrate what’s possible, the Montex line at the ATC is able to treat materials not only at temperatures of up to 320°C, but apply separate coatings on the two sides of certain materials at different temperatures, within a single pass through the machine. To achieve this, the first two chambers of the stenter are fitted with TwinTherm burners for individual top/bottom heating. A temperature differential of up to 60°C can be achieved between the upper and lower nozzles within the chamber, depending on the treatment parameters.

“There are many applications where employing two separate temperature treatments is beneficial, such as floorcoverings – where the textile face fabric is treated at one temperature and the rubber backing at another – as well as PVC flooring employing chemical foams, black-out roller blinds with heavy backings or PTFE-coated filter materials,” Gesser explains.

Another key feature of the technical textiles line at the ATC is the Montex stenter’s special stretching device which is capable of pulling ten tons in length and ten tons in width – a huge amount per square metre of fabric and necessary in the production of materials such as woven or 3D knits for high temperature filter media.

Monforts also offers the special T-max grease-free stenter chain for high temperature treatments up to 320°C, at machine speeds up to 100m/min and transverse tension up to 2,500 N/m with the benefits of no maintenance and no grease marks on fabric.

“Technical textiles are extremely diverse in their end-use applications but the needs of the manufacturers of very different materials are still uniform in many respects,” says Gesser. “European-built Montex stenters provide maximum finishing efficiency and many of our customers are operating them 24 hours a day over seamless shifts.”

Existing customers include manufacturers in the fields of home textiles, geotextiles and automotive fabrics, as well as functional materials and dedicated Montex lines have also been supplied to producers of airbags, flame retardant barrier fabrics and spacer fabrics.

“Techtextil North America is a very important show for us because technical textiles are a key pillar of our production programme,” Gesser concludes. “North America is one of our major markets and we are looking forward to reconnecting with existing and potentially new customers at this always-vibrant show.”

Researchers at the ITA, the University of Bonn and Heimbach GmbH have developed a new method for removing oil spills from water surfaces in an energy-saving, cost-effective way and without the use of toxic substances. The method is made possible by a technical textile that is integrated into a floating container. A single small device can remove up to 4 liters of diesel within an hour. This corresponds to about 100 m2 of oil film on a water surface.
 
Despite the steady expansion of renewable energies, global oil production, oil consumption and the risk of oil pollution have increased steadily over the last two decades. In 2022, global oil production amounted to 4.4 billion tons! Accidents often occur during the extraction, transportation and use of oil, resulting in serious and sometimes irreversible environmental pollution and harm to humans.

There are various methods for removing this oil pollution from water surfaces. However, all methods have various shortcomings that make them difficult to use and, in particular, limit the removal of oil from inland waters.

For many technical applications, unexpected solutions come from the field of biology. Millions of years of evolution led to optimized surfaces of living organisms for their interaction with the environment. Solutions - often rather unfamiliar to materials scientists and difficult to accept. The long-time routine examination of around 20,000 different species showed that there is an almost infinite variety of structures and functionalities. Some species in particular stand out for their excellent oil adsorption properties. It was shown that, e.g., leaves of the floating fern Salvinia molesta, adsorb oil, separate it from water surfaces and transport it on their surfaces (Figure 1, see also the video of the phenomon.).

The observations inspired them to transfer the effect to technical textiles for separating oil and water. The result is a superhydrophobic spacer fabric that can be produced industrially and is therefore easily scalable.

The bio-inspired textile can be integrated into a device for oil-water separation. This entire device is called a Bionic Oil Adsorber (BOA). Figure 2: Cross-section of computer-aided (CAD) model of the Bionic Oil Adsorber. The scheme shows an oil film (red) on a water surface (light blue). In the floating cotainer(gray), the textile (orange) is fixed so that it is in contact with the oil film and the end protrudes into the container. The oil is adsorbed and transported by the BOA textile. As shown in the cross-section, it enters the contain-er, where it is released again and accumulates at the bottom of the container. See also the video regarding the oil absorption on the textile, source ITA).
 
Starting from the contamination in the form of an oil film on the water surface, the separation and collection process works according to the following steps:

• The BOA is introduced into the oil film.
• The oil is adsorbed by the textile and separated from the water at the same time.
• The oil is transported through the textile into the collection container.
• The oil drips from the textile into the collection container.
• The oil is collected until the container is emptied.

The advantage of this novel oil separation device is that no additional energy has to be applied to operate the BOA. The oil is separated from the surrounding water by the surface properties of the textile and transported through the textile driven solely by capillary forces, even against gravity. When it reaches the end of the textile in the collection container, the oil desorbs without any further external influence due to gravitational forces. With the current scale approximately 4 L of diesel can be separated from water by one device of the Bionic Oil Adsorber per hour.

• It seems unlikely that a functionalized knitted spacer textile is cheaper than a conventional nonwoven, like it is commonly used for oil sorbents. However, since it is a functional material, the costs must be related to the amount of oil removed. In this respect, if we compare the sales price of the BOA textile with the sales prices of various oil-binding nonwovens, the former is 5 to 13 times cheaper with 10 ct/L oil removed.
  Overall, the BOA device offers a cost-effective and sustainable method of oil-water separation in contrast to conventional cleaning methods due to the following advantages:
• No additional energy requirements, such as with oil skimmers, are necessary
• No toxic substances are introduced into the water body, such as with oil dispersants
• The textiles and equipment can be reused multiple times
• No waste remains inside the water body
• Inexpensive in terms of the amount of oil removed.
• The team of researchers from the ITA, the University of Bonn and Heimbach GmbH was able to prove that the novel biomimetic BOA technology is surprisingly efficient and sustainable for a self-controlled separation and automatic collection of oil films including their complete removal from the water. BOA can be asapted for open water application but also for the use in inland waters. Furthermore, it is promising, that the textile can be used in various related separation processes. The product is currently being further developed so that it can be launched on the market in 2-3 years.

The Techtextil and Heimtextil Summer Special exhibitions, taking place together in Frankfurt from June 21-24, represent an opportunity for Monforts to showcase its finishing and coating technologies for two of its major markets – especially at a time when energy prices continue to soar for textile manufacturers in Europe.

Existing customers of Monforts include many manufacturers in the field of home textiles, as well as those making geotextiles, automotive fabrics and other functional materials – all of whom will be well represented in Frankfurt this June. Dedicated Montex lines have also been supplied to producers of airbags, flame retardant barrier fabrics and spacer fabrics, as well as high-temperature filter materials.

Energy prices are rising steeply everywhere and a particular emphasis for Monforts in Frankfurt will be on the energy and heat recovery that can be achieved with Montex stenters, through features such as better insulation of the treatment chambers or the MonforClean system, in which waste heat from the drying process is used to pre-heat the drying air resulting in a radical reduction in the conventional heat supply required compared to gas and thermal oil heating. The modular system for heat recovery can also be extended for exhaust air cleaning and odour elimination. Monforts can provide a range of further resource-saving and energy recovery options tailored to each individual line installation including modification of the heating source.

With the Qualitex 800 visualization software, all article-specific settings can be stored and the formulations for thousands of treatment processes called up again at any time. Individual operators can also personalise their dashboards with the most important machine functions and process parameters.

The Qualitex 800 system is available for the automatic and continuous operation of the company’s Montex stenters, as well as its Thermex continuous dyeing ranges, Monfortex shrinking systems and Montex®Coat coating units.

Monforts Montex®Coat coating units serve an equally diverse number of markets, including tents, tarpaulins and awnings, black-out roller blinds and sail cloth, automotive interior fabrics and medical disposables. Full PVC coatings, pigment dyeing or minimal application surface and low penetration treatments and solvent coatings (in explosion-proof conditions) with knife coating, roller coating or screen printing can all be accommodated with this system.

All of these very different materials require coating and finishing for maximum efficiency, using Monforts technologies which provide the ultimate in flexibility and the ability to switch quickly from one fabric run to the next, without compromising on the economical use of energy or raw materials.

The Monforts EcoApplicator offers further potential for sustainably achieving perfect finishes via a precise direct application system, as an alternative to conventional padding – where fabrics are immersed in a bath of the required finishing chemicals. It can significantly further reduce the energy and water required and finishes can be applied on just one side of the fabric, or both, and even separately on each side, to be sealed in place via different heating zones in the stenter.

Mayer & Cie. (MCT) is premiering the OVJA 1.1 EETT at the industry’s leading trade fair, ITMA. A premium jacquard machine, it is part of the focus on sports of the company’s “Stay a winner: With Mayer & Cie.” presentation in Barcelona. The industry leader developed the OVJA 1.1 EETT especially for the manufacture of shoe uppers now that “fabrics” are in demand for sports and leisure footwear. The OVJA 1.1 EETT comes with double electronics and double transfer technology, which is reflected in an extra variety of patterns and, in particular, in innovative hole structures.

“The OVJA 1.1 EETT is yet another machine in our portfolio with which customers can claim to be on the winning side in keeping with our ITMA slogan ‘Stay a winner: With Mayer & Cie.’,” says Marcus Mayer, Managing Director of Mayer & Cie. in charge of technical development. “The OVJA 1.1 EETT is most definitely a premium machine and the right choice for especially exacting requirements such as multi-coloured spacer fabrics with a 3D effect or a wide range of hole structures.”