Key Facts

CL 71 Ultrapox FlexPrimer

Solvent-free epoxy primer with high strength & easy application


  • Deep penetration
  • Easy application
  • Solvent-free
  • High strengthening effect
  • Barrier effect against rising and penetrating damp
  • For critical substrates
  • Ensures a reliable bond
  • For absorbent and non-absorbent substrates
  • For indoor and outdoor use


CL 71 is a 2-component epoxy-resin primer used to prime specially critical surfaces -  e.g. metal, mastic asphalt and old paint - and also absorbent and non-absorbent surfaces - e.g. CSA screeds when installing large-format tiles. It is also suitable for use in the UltraPox system before CL 72 Ultrapox FlexSeal is applied.

Step By Step

Preparation & mixing

Before applying CL 71, test the load-bearing capacity and strength of the substrate. Clean the surface and remove any dust. CL 71 is a reactive system with 2 components supplied in one container. Mix the two components with a low-speed electric drill (400 rpm) and stir until the mixture is completely homogenous and free of lumps.
Please refer to the Technical Data sheet!


Apply CL 71 undiluted with a brush, broom or roller (observe the open time of 30min). Directly after application, the freshly primed surface must be entirely sprinkled with fire-dried quartz sand of grain size 0.2 to 0.6 mm (e.g. H33). Completely remove any loose remaining sand after the primer has cured.

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