Crack seal products are used to fill individual pavement cracks to prevent entry of water or other non-compressible substances such as sand, dirt, rocks or weeds. Crack sealant is typically used on early stage longitudinal cracks, transverse cracks, reflection cracks and block cracks.

Fatigue cracks are most often too extensive to warrant filling with crack sealer; they usually require an area treatment such as a patch or reconstruction. Crack filler material is typically some form of rubberized asphalt or sand slurry.
Purpose
Preventive maintenance. Crack filling to prevent entry of water or other non-compressible substances into the pavement.
 
Materials
Heated liquid asphalt (often some form of rubberized asphalt).
 
Mix Design
Various, including proprietary methods.
 
Other Info
:: Before applying crack sealant, cracks need to be routed out and cleaned.
:: Crack sealing is best done in moderate temperatures (spring or fall) and is most effective if performed immediately after cracks develop.
:: Reported average performance life ranges from about 3 – 8 years.
 
BS group is ready to provide suitable material, equipment and give you advice to achieve best result.
 
 
Footnotes
Ref: http://www.pavementinteractive.org/article/crack-seals/