As global demand for personal protective equipment continues to rise, Karl Mayer’s Technical Textiles business unit has advanced its development of ultra-lightweight multiaxial non-crimp fabrics. These are specifically designed for use in bulletproof protective vests, with significant improvements in comfort, strength, and efficiency.

According to Dr Jürgen Tröltzsch, Special Specification Project Manager at Karl Mayer, the company is experiencing increasing enquiries from across Europe for high-performance textile protection solutions. Traditional aramid fibres have long been used for this purpose, but despite their high strength, the resulting protective layers are often too heavy. Depending on the protection level, up to 70 layers may be required, resulting in weight and comfort issues.

To overcome this, Karl Mayer has focused on the use of ultra-high molecular weight polyethylene (UHMWPE) fibres. These fibres offer comparable ballistic performance to aramid but at a significantly lower weight. With tensile strengths exceeding 3.5 GPa, UHMWPE allows for material reductions without compromising safety.

Utilising its UD 700 fibre spreading machine, Karl Mayer has developed a process for producing single-layer tapes from UHMWPE fibres. These are then formed into cross-ply structures on the COP MAX 5 multiaxial warp knitting machine. Spread layers can be produced at thicknesses as low as 40 to 50 µm, with weights under 30 g/m² - less than a third of conventional aramid layers.

To maintain the structural integrity of these ultra-light layers, Karl Mayer has integrated a wafer-thin polymer film, just 10 µm thick, onto the tapes during spreading. This ensures fibre stability and eliminates weak spots, or “lanes”, that could compromise performance. The fibre and film are bonded via an integrated heating module, without the need for liquid chemicals or water evaporation, making the process cleaner and more energy efficient.

The multilayer tapes are then joined in alternating 0° and 90° orientations to form cross-ply constructions, stacked automatically up to six layers deep. While manual stacking remains common in production, Karl Mayer’s automated system has impressed visitors seeking advanced solutions for protective textile production.

Independent testing of UHMWPE cross-plies in 2021 by the Mellrichstadt State Procurement Office confirmed their performance. Under the stringent NIJ Standard 0101.06, the materials successfully passed both perforation and backface signature tests at a total weight of 6,000 g/m².

Karl Mayer’s technology presents several key benefits: improved yarn alignment, compatibility with higher yarn counts, reduced material and labour costs, and a simplified creel setup. The fibre and film bonding process avoids the use of resins or energy-intensive water removal, streamlining production further.

As security needs intensify, Karl Mayer’s innovations demonstrate how textile engineering can lead the way in creating safer, more efficient protective solutions.

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