The thermoplastic is applied by extrusion to form a pattern of dots with or without a baseline and immediately reflectorised to create a Structured Type II Road marking. The surface dots of the road marking gives the product superior performance (dots protrude above the surface water) in terms of visibility to road users in adverse conditions, for instance when it is dark and the road surface is wet.
The application speed is normally 2 – 5 km/h.
- As edge, lane lines or centre line markings on single carriageway roads. As lane lines and merge/diverge lines on Dual Carriageways / Motorways.
The advantage of road marking with Dots is:
• Higher retro reflectivity because of the many vertical “walls”. This advantage is increased in wet weather as water will not collect on the surface as on a flat line.
• Warning of the driver against driving of the road, as it makes noise when the tyres hit the Dots.
Road marking with Dots is divided into two types:
• Dots alone
• Dots on a base line
The Dot specification for both types is:
Number of Dots per metre of line is 15 – 35. The number of Dots is controlled by the Line Master computer, and can be varied while the road marking is being applied.
Diameter of Dots can vary between ø18 and ø45 mm.
The Dot size is a function of the diameter of the holes in the rotating drum in the equipment.
Number of Dots across the line is usually according to the size of the shutters.
For 5 mm shutters there will be 25 mm space between the centre of the Dots.
|Retroreflectivity – dry||R4||200 mcd||R4||200 mcd|
|Retroreflectivity – wet||RW4||75 mcd||RW4||75 mcd|
|Luminance on road||Q4||160 mcd||Q4||160 mcd|
|Application Temp °C||150 – 200|
|Flash Point °C||> 230|
|Density (g/cm³)||1.9 – 2.1|
|Application Speed km/h||02-May|