D-MASTIC is an alkyl resin modified, oil based caulking compound. It forms a tack-free skin on the surface when exposed to air but remains soft underneath.

D-MASTIC is black in colour.


Finds greatest use as a sealant when installing/replacing gasket fixed type windscreens in cars, boats, trucks, buses and as a sealant for lap joins between metal panels in automotive and expanded foam sandwich panel assemblies. A general purpose mastic sealant for any exterior exposed joints subject to little or no movement for the exclusion of dust, draughts and rain.

Product Range

Product Code: 9300697100023

  • Size & Pack Type: 400g cartridge
  • Color: Black

Technical Features

  • Adheres well to most substrates including metal, glass, concrete, masonry and timber
  • Forms a surface skin, preventing transfer by touch and dirt pick-up on exposed surfaces
  • Paintable (after skin has formed)
  • Easy clean-up off non-porous surfaces with mineral turpentine
  • Convenient to use non-slumping from vertical joints and easily extrudable
  • Long “open” time assists in the assembly of lap joints

Application Tips

  • Not an elastomeric compound, it should not be used in joints subject to considerable dynamic movement
  • Maximum service is achieved when used within joints, it is not recommended to be used as a “skim” coating over joints
  • Not recommended for use in joints required to resist static air or water pressure

Technical Details and Performance

Indicative information only, not to be used for setting specifications.



Viscosity (Brookfield HAF 7/2@ 25oC, Poise)

10,000 – 20,000

Slump (MIL-S-8802, mm Maximum)


Tack Free Time (Hours, Maximum)


Specific Gravity @ 25oC

1.46 ± 0.05

Flash Point (oC)


Storage Life (25oC, month)



400gm (300ml)

Joint Movement Capability

± 5%

Service Temperature

10oC to +70oC

Life Expectancy

Up to 10 years

Clean Up

Clean off tools, spills and squeeze out with cloth dampened in mineral turpentine, kerosene or white spirits

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