Since naphthenic bitumen are no longer available, content of bitumen in mastic asphalt has been significantly increased to maintain workability.
The patented Rulyfalt® technology increases the workability of mastic asphalt through lubrication of the limestone filler. Thus, it is possible to reduce the bitumen content, or the temperature, or both.
The reduction of production temperature limits the oxidation of the bitumen and thus increases indentation. Consequently, the addition of another additive (wax, natural bitumen, oxidized bitumen) may be necessary to reach the indentation specification.