Bitumen paint

Bitumen paint or colored bitumen emulsions are highly appropriate for painting roads, airport runways and camouflage

of military buildings and producing colored asphalts. Bitumen paint emulsions contain less than 25% by weight of bitumen along

with color pigments and insoluble materials.

Insoluble materials contribute to the stability of the emulsion and especially the stability of the pigment in the emulsion.

Producers have tried different methods to prepare bitumen paint emulsions.

Besides, manufacturers have always tried to reduce the amount of bitumen in the emulsion and increase

the amount of full-color emulsion pigment by increasing the amount of black bitumen

so that the black color of bitumen disappears completely.

To prepare such an emulsion, they first prepare bitumen emulsion and the color pigment emulsion separately and then mix.

It’s worth mentioning that Iron oxide pigment is appropriate for preparing red bitumen and cream oxide pigment is appropriate

for making green bitumen. Importantly, they fully color emulsions with a weight ratio of one to one bitumen and pigment.

Generally speaking, manufacturers produce bitumen paint by mixing bitumen with pigments. These pigments have two categories,

organic and artificial. Artificial pigments such as iron oxide, chromium oxide,

titanium dioxide and mixed pigments (such as cobalt blue) are suitable for coloring bituminous mixtures.

Moreover, these pigments are durable in all climatic conditions, but organic pigments are sensitive

to heat and weather conditions. Now, let’s discuss the pigments in detail.

Pigments are physically available in the following four forms:

The particle size in the compact type is at best between 0.0001 and 0.001 mm. To make this type of pigment,

fine pigment particles mix in a bitumen paint-compatible binder (such as cement mortar) to stick together and form small compact spheres.

This binder controls the amount of compaction of the pigments to ensure that they remain stable

during transport and storage and at the same time break easily in the asphalt and bitumen paint mixture.

Important to know that powder pigments are very small particles that do not flow easily.

To put it differently, a mechanical device such as a vibrator must be available when emptying the storage silos.

However, compact pigments, because they easily melt, can be stored in silos and do not generate dust.

Another advantage of compacted pigments is that they have a higher bulk density

than the powder type, which makes them take up less space during storage.