The great increase in vehicle traffic, the extension of the motorway network and continual evolution in the quality of road surfaces has provided a challenge to tar manufacturing companies. PROAS has three ranges of Tars, two ranges of Emulsions and a "special" range of specific solutions, all of them for their application on the road

Asphalt Tars are a heavy fraction of the petroleum where chemical compounds with molecular weights exceeding 600 are found.

Their appropriateness for road construction is due to their rheological behaviour. 

At high temperatures, tar behaves like a liquid, which allows it to be mixed with aggregates, while at a lower temperature it behaves like an elastic solid, increasing its viscosity enough to make the mix cohesive and to be able to resist the effort caused by the traffic without suffering permanent deformation.

Among Asphalt Tars, PROAS offers three ranges of highly developed tars:

• The CEPSASFALT® range includes what are known as asphalt tars.
• The STYRELF® range is comprised of polymer modified tars.
• The FLEXODUR® range is comprised of rubber modified tars.
• Bitumen emulsions are tar (either conventional or modified) dispersed in water, where the continuous base is water and the discontinuous one micrometric tar particles (micelles).

Its major advantage is that it allows tar to be applied at ambient temperature on the roads, using different cold techniques: asphalt mixes, bitumen grouts, spraying with fine gravel, etc. 

PROAS has all the kinds of bitumen emulsions used in the road market, covered by two ranges:

• The EMASFALT® range groups the cationic and anionic emulsions.
• The STYEMUL® range, formed by the bitumen emulsions obtained from STYRELF® modified tar, that provides these better characteristics.

As a complement to its tar and emulsion families, PROAS has developed a range of exclusive products, able to satisfy the most stringent road demands. This range called NOVACEP offers products that provide specific solutions in specific applications, such as pavement recycling, anti-fissure treatments, high performance mixes, asphalt emulsions for cold and semi-hot recycling, etc.