German compounder and distributor Lehmann & Voss (LuV, Hamburg; www.lehvoss.de/eng) has introduced a new class of carbon/silica fillers. Its "Luvomaxx CF" range is comprised of naturally-occurring carbon and crypto-crystalline silica; thus it is not subject to Europe’s REACH regulation and, according to LuV, also gives very good CO₂ emission figures.
A key feature of Luvomaxx CF is its platelet structure, which can significantly increase the gas impermeability of components carrying air, such as inner liners for tyres, hoses and gaskets. LuV said Luvomaxx CF’s morphology also makes it suitable for reducing the dynamic properties of vulcanised rubbers, such as internal friction which can result in a corresponding reduction in material fatigue.

In addition, the fillers have a much lower density (1.3-1.7g/cm³) compared with other mineral fillers or carbon blacks, helping to significantly reduce mixing costs. They also display low-dust dispersibility in natural and synthetic rubbers and can be used as internal dispersing aid in combination with carbon black to improve its distribution – the improved flow properties result in smoother surfaces.