LANXESS offers Bayferrox and Colortherm pigments that are suitable for the colouring of bituminous mixtures used as the raw materials for all asphalt types, such as grid mastic asphalt, noise-reducing and semi-rigid asphalt or asphalt concrete. Asphalt’s core ingredients are aggregate, bitumen, additives and air. Bitumen is produced in various grades of hardness. Depending on the mix and grade of bitumen used, it is possible to lay road surfaces to meet a wide variety of requirements. Coloured asphalt is increasingly being used not only in road construction but also in gardens and landscape architecture. Coloured asphalt pavement can be used to differentiate bike paths from roads and direct traffic. It is also ideally suited to highlight dangerous points or make areas attractive. For e.g. functional colour differentiation can highlight pedestrian and bicycle paths, thus increasing the safety of road users.
The colour is influenced mainly by the type of bitumen used. Dark bitumens are most commonly coloured red using inherently heat-stable iron oxide red pigments with high tinting strength. By using a clear polymer bitumen, the colour spectrum can be extended to even yellow or green surfaces.
LANXESS pigments provide further decisive benefits. Bayferrox 130 A red pigment, for example, provides high heat stability. Being produced via the Laux-Process, the product’s colour is not influenced even at the high manufacturing temperatures which are applied during the production of mastic asphalt. Bayferrox 130 A is also available in low-melt PE bags, which can be dosed manually directly into the asphalt mix.
With a higher push on infrastructure development over the last couple of years, the road construction industry in India is undergoing a paradigm shift. Strong demand, higher investments, and innovative and emerging technologies are reshaping the dynamics of road construction with a renewed focus on sustainable development.