From the Sector

Many end-users now expect recycled materials to be in textile products they purchase – and this is driving innovation throughout the industry. However, there are still many technical and economic issues facing yarn and fabric producers using recycled resources. Members of the Swiss Textile Machinery Association offer some effective solutions to these challenges.

Synthetic recycled materials such as PET can usually be treated similarly to new yarn, but there are additional complexities where natural fibres like wool and cotton are involved. Today, there’s a trend towards mechanically recycled wool and cotton fibres.

Spinning recycled cotton
The use of mechanically recycled fibres in spinning brings specific quality considerations: they have higher levels of short fibres and neps – and may often be colored, particularly if post-consumer material is used. It’s also true that recycled yarns have limitations in terms of fineness. The Uster Statistics 2023 edition features an extended range of fibre data, supporting sustainability goals, including benchmarks for blends of virgin and recycled cotton.
In general, short fibres such as those in recycled material can easily be handled by rotor spinning machines. For ring spinning, the shorter the fibres, the more difficult it is to guide them through the drafting zone to integrate them into the yarn body. Still, for wider yarn counts and higher yarn quality, the focus is now shifting to ring spinning. The presence of short fibres is a challenge, but Rieter offers solutions to address this issue.

Knitting recycled wool
For recycling, wool fibres undergo mechanical procedures such as shredding, cutting, and re-spinning, influencing the quality and characteristics of the resulting yarn. These operations remove the natural scales and variations in fibre length of the wool, causing a decrease in the overall strength and durability of the recycled yarn. This makes the yarn more prone to breakage, especially under the tension exerted during knitting.

Adapting to process recycled materials often requires adjustments to existing machinery. Knitting machines must be equipped with positive yarn suppliers to control fibre tension. Steiger engages in continuous testing of new yarns on the market, to check their suitability for processing on knitting machines. For satisfactory quality, the challenges intensify, with natural yarns requiring careful consideration and adaptation in the knitting processes.

From fibres to nonwovens
Nonwovens technology was born partly from the idea of recycling to reduce manufacturing costs and to process textile waste and previously unusable materials into fabric structures. Nonwovens production lines, where fibre webs are bonded mechanically, thermally or chemically, can easily process almost all mechanically and chemically recycled fibres.

Autefa Solutions offers nonwovens lines from a single source, enabling products such as liners, wipes, wadding and insulation to be produced in a true closed loop. Fibres are often used up to four times for one product.

Recycling: total strategy
Great services, technology and machines from members of Swiss Textile Machinery support the efforts of the circular economy to process recycled fibres. The machines incorporate the know-how of several decades, with the innovative power and quality standards in production and materials.
Stäubli’s global ESG (environmental, social & governance) strategy defines KPIs in the context of energy consumption, machine longevity and the recycling capacity in production units worldwide, as well in terms of machinery recyclability. The machine recyclability of automatic drawing in machines, weaving systems and jacquard machines ranges from 96 to 99%.

UK’s Optima 3D is delivering its weaving technology to the USA, for installation at the University of Maine’s Advanced Structures and Composites Center (ASCC).

The 3D weaving system consists of an Optima 3D Series 600 shuttle weaving machine with an integrated 2,688-hook Stäubli SX jacquard and harness. It is also complemented by Optima’s compact warp delivery creel and an associated pirn winder for shuttle bobbins and a spool winder for creel spools.

Optima’s looms offer many advanced features over conventional weaving machines, particularly in terms of versatility, as a result of the comprehensive use of digital control systems allowing rapid parameter and sequence changes, coupled with an innovative shuttle system.

The ASCC is certainly no stranger to advanced technology, or indeed ambitious composite projects – in 2019 it received no less than three Guinness World Records, for the world’s largest prototype polymer 3D printer, the largest solid 3D-printed object, and the largest 3D-printed boat. In its latest project it has further introduced BioHome3D – the first 3D-printed house made entirely with bio-based materials developed in a partnership with Oak Ridge National Laboratory. The 182-square-metre prototype features 3D-printed floors, walls and roof which are fully recyclable and highly insulated with 100% wood insulation and customisable R-values. Construction waste was nearly eliminated due to the precision of the printing process.

New ideas were exchanged, brainstormed, and discussed freely at members’ booths at the Swiss Textile Machinery Pavilion during the recent Techtextil in Frankfurt. “Customers and researchers met Swiss textile machinery companies to explore the possibility of the not-yet-invented. “We regard our Pavilion as the place where future innovations catch a spark,” says Cornelia Buchwalder, Secretary General of the Swiss Textile Machinery Association. Further developments in the field of hybrid yarns were a hot topic. One example of this involves producing a yarn which has all the typical characteristics and advantages of carbon – but which also prioritizes careful use of resources, combining carbon fibres with thermoplastics.

Technical textiles cover a vast range of applications, and it’s still growing thanks to intensive research by specialist institutes and universities. Many members of the Swiss Textile Machinery Association maintain long-standing partnership with such bodies. Innovations are often joint efforts.

Feel-good technical fabrics
Some technical textiles feel like a second skin. A well-known example is activewear from the ‘sport tech’ field. Activewear includes breathable clothing, usually consisting of a three-layer-laminate: an inner lining, a breathable membrane in the center, and an outer fabric. The challenge is to bond the individual layers without losing breathability or softness, while meeting technical requirements such as resistance to a number of wash cycles.

Bonding solutions meeting top quality requirements, as well as ambitious standards for environmental protection and sustainability, were reinvented by the Cavitec brand from the Santex Rimar Group. This company’s hotmelt technology uses one-component polymers applied to textiles in a hot, molten state. Bonding based on hotmelts is both water- and solvent-free. Drying and exhaust air cleaning are not necessary, which is an ecological advantage. Energy consumption is also significantly lower. Cavitec hotmelt technology is also developed for laminated medical protection fabrics which are safe, high-quality and sustainable. These fabrics can be washed, sterilized, and used again.   

A second skin with added value is the result of Jakob Müller Group’s cooperation with an institute for an established outdoor fashion brand. They have devised a heating mat applied as an inner jacket. Outdoor gear with a heated inlay offers the wearer a comfortable feeling even in a cold climate. The heating mat is particularly light, breathable, flexible and adjustable to three temperature levels.

Fabrics with these advantages are now possible thanks to multi direct weaving (MDW) technology from the Jakob Müller Group. A lacquer-insulated heating strand is inserted into the base textile as a ‘meander’ using MDW technology. The technology is offered with both label weaving machines and the latest generation of ribbon weaving machines. The textile pocket calculator is another MDW based future-oriented application developed in cooperation with a textile research institute.

Safety and health
Life-saving reliability is a must for vehicle airbags. They have to fulfil high security aspects, and must remain inflated for several seconds when an accident occurs. Airbags made of flat-woven fabric – cut and seamed – can show weakness at seams during the inflation phase. Latest Jacquard technology by Stäubli enables one-piece-woven (OPW) airbags to be produced, creating shape and structure in a single process. The final product is an airbag consisting of a sealed cushion with woven seams. OPW airbag weaving reduces the number of production steps, and increases the security aspects.
Another big advantage of Stäubli’s new weaving technology is the flexibility in formats required in today’s mid- and upper-range cars, where lateral protection (in the seat or in the roof over the door) has become standard and is designed in line with the car shape. Safe airbags are woven on modern high-speed weaving machines. The warp material, the variety of fabric patterns, and the importance of precisely shaped airbags require the use of a robust and reliable Jacquard machine.

A revolution for orthopaedic patients is a knitting machine from Steiger Participations, which uses compressive yarns developed to meet the needs of the specific health market. This machine model was exclusively designed for production with inlaid elastic yarns and offers optimum performance with guaranteed final product quality.

In the orthopaedic field, many Steiger flat knitting machines have already been operating as automatic, custom-made production systems. For example, the dimensions of an injured limb are taken by the doctor and fed into a web-based application. The doctor selects the compression class in the various sections of the item and a data file created by the software automatically applies a preconfigured program. With no human intervention required, the program is generated and produced on the machine, precisely matching the patient’s dimensions. Each product is different, and generally available within 48 hours.

SHIMA SEIKI MFG. will participate in the ITM 2022 International Textile Machinery Exhibition in Istanbul, Turkey.

SHIMA SEIKI will exhibit a wide range of its products, including proposals in seam-free WHOLEGARMENT® knitting technology that offers an alternative to labor-intensive manufacturing in Turkey and other international markets. Featured is the flagship MACH2XS WHOLEGARMENT® knitting machine with original SlideNeedle™ on four needle beds and spring-loaded moveable sinkers with expanded patterning capability, the MACH2VS V-bed machine for producing WHOLEGARMENT® items using every other needle, as well as the compact SWG091N2 for producing smaller WHOLEGARMENT® items and accessories. A brand new proposal in V-bed WHOLEGARMENT® knitting will also be introduced in the form of the N.SVR183 machine. N.SVR123SP features a special loop presser bed that can produce hybrid inlay fabrics with both knit and weave characteristics. N.SVR123SP at ITM will feature the special i-Plating option, capable of alternating yarn colors in any pattern, producing jacquard-like designs using plain jersey stitch for even greater diversity in knit design. Meanwhile N.SSR112 offers industry-leading technology in an economical yet reliable package made in Japan. Also on display is the SFG20 glove knitting machine.

Demonstrations will be performed on SHIMA SEIKI’s SDS®-ONE APEX4 design system. At the core of the company’s “Total Fashion System” concept, SDS®-ONE APEX4 provides comprehensive support throughout the production supply chain, integrating production into one smooth and efficient workflow from yarn development, product planning and design, to production and even sales promotion. Especially effective is the way SDS®-ONE APEX4 improves on the design evaluation process with its ultra-realistic simulation capability, whereby virtual samples replace physical sampling, consequently reducing time, cost and material that otherwise go to waste. The same capability is present in APEXFiz™ subscription-based design software. Installed on personal computers, APEXFiz™ features the same functionality as SDS®-ONE APEX4, but with the added versatility to adapt to different work styles and business environments including teleworking and telecommuting. Digital prototyping using virtual samples on SDS®-ONE APEX4 and APEXFiz™ help to digitally transform the fashion supply chain for realizing sustainable manufacturing. APEXFiz™ will be shown along with SHIMA SEIKI’s yarnbank™ digital yarn web platform that further enhances the realism of virtual samples.

SHIMA SEIKI ITALIA S.p.A., Italian subsidiary of leading Japanese computerized knitting solutions provider SHIMA SEIKI MFG., LTD., will exhibit at the 90th edition of the Pitti Immagine Filati exhibition in Florence, Italy. Products exhibited will include the N.SVR®123SP computerized flat knitting machine as well as APEXFiz™ design software.

The N.SVR®123SP computerized knitting machine features a special loop presser bed, capable of producing hybrid inlay fabrics with both knit and weave characteristics. Demand for such novel fabrics are very high across a wide range of applications, from fashion apparel to sportswear, innerwear, outerwear, uniforms and other functional clothing, as well as home furnishing and technical textiles. Shown in 18G at the SHIMA SEIKI booth, N.SVR®123SP will also feature the special i-Plating option, capable of alternating yarn colors in any pattern, producing jacquard-like designs using plain jersey stitch. Plating can be performed within the same course and for individual needles. In combination with the loop presser and spring-type moveable sinker system even greater diversity in knit design is possible. An SVR®123SP machine in 14G with i-Plating option will also be on display at the booth of yarn spinner IAFIL S.p.A. as well.

APEXFiz™ is subscription-based design software that maintains the proven functions that have made SHIMA SEIKI’s SDS®-ONE APEX series design systems so popular with fashion designers. Installed on personal computers, those strengths are now enhanced with the added versatility to adapt to different work styles and business environments including teleworking and telecommuting. APEXFiz™ software supports the creative side of fashion from planning and design to colorway evaluation, realistic fabric simulation and 3D virtual sampling. Virtual samples are a digitized version of sample making that are accurate enough to be used effectively as prototypes, replacing physical sampling and consequently reducing time, cost and material that otherwise go to waste. APEXFiz™ thereby helps to realize sustainability and digitally transform the fashion supply chain.

APEXFiz™ along with SHIMA SEIKI’s yarnbank™ digital yarn web platform are featured at a special section launched at the previous session of Pitti Filati no. 89 called Pitti Studios. Pitti Studios is a content production service that yarn companies exhibiting at Pitti Filati can use for their own promotion. Yarn companies provide a piece of yarn, which is digitized on yarnbank™ and used to simulate photorealistic fabric on APEXFiz™. This is then processed by a creative studio specializing in digital content to provide static and animated 3D virtual representations. The process shows how to use the latest DX tools to provide accurate representation of a finished garment without having to produce any fabric, converting the conventionally wasteful process of sample-making into a sustainable one.

Continuing from past editions of Pitti Filati are knit samples produced in collaboration with Italian designer Vittorio Branchizio.

Wülfing GmbH is one of the oldest but also one of the most modern home textiles companies in Germany, with its main weaving and finishing operations located in Borken, North Rhine-Westphalia, and a further jacquard weaving mill in Steinfurt, as well as with a making up and packaging plant in the Czech Republic.

At its Borken plant, Wülfing has employed a Monforts sanforizing line since 2009 to guarantee the required dimensional stability and shrink-fastness of its high quality bed linen. With a working width of over three metres, the sanforizing process is a central pillar in the production of typical wide-width cotton fabrics for home textiles.

In 2017, the company was able to acquire a second Monforts sanforizing line from another company which, although built in 2005, had been virtually unused. It was overhauled and installed behind a Monforts equalizing frame of a similar age.

“Unfortunately, the two machines had to be operated separately via individual controls and did not represent an integrated unit,” says Schulte-Mesum. “This resulted in deficits in the desired productivity and in the control technology.”

Wülfing consulted with Monforts on a number of upgrade options and opted for a completely new joint control system to merge the two machines, as well as a new connecting inlet, a tensioning and damping field and a steaming unit.

“Monforts provided a fast and precise erection and commissioning of the technology in spite of the difficult pandemic circumstances,” says Schulte-Mesum. “The result has been an increase in production speeds by 20% and enhanced uniformity in fabric width through a much improved guidance system.

“We are also achieving energy savings as a result of the new control and drive technology and operation has been simplified and improved as a result of the unified control. We benefit from simplified access for maintenance work such as the grinding of the rubber blanket, but most of all we have greatly improved our flexibility and now have two almost identical Monforts sanforizing lines.”