Microprimer PU for Polyurethane

Low Viscosity, Aliphatic, Non-Staining Polyurethane Based Primer/ Concrete Sealer, for both Porous & Non-Porous Substrates


MICROPRIMER is a one component, low viscosity, 100% aliphatic polyurethane-based primer suitable for all substrates. It is characterised by its very low viscosity, excellent impregnation, non-yellowing (non-staining) properties combined with a relatively fast cure speed and most importantly its excellent adhesion on both non-porous and porous substrates. The cured film shows good mechanical properties: Its elongation is >50%, and its tensile strength surpasses 40 N/mm2. Apply with brush or roller.  Consumption: 50-200 gr/m2, subject to substrate porosity.


To be used as primer for:

  • Hyperseal Sealants when a non staining primer is required
  • ceramic tiles,
  • non-porous substrates  like glass, marble & metals.

Also, for use as concrete sealer.


100% Aliphatic Polyurethane; No yellowing, No staining

  • One component.
  • Of low viscosity.
  • Relatively quick curing
  • Adheres strongly, even on glassy, non-porous substrates.
  • Excellent wetting, impregnation and paint-over time.
  • Many pigment pastes available.


Before vulcanization Appearance Achromatic transparent
  Viscosity (Brookfield), cP 20
  Specific weight, gr/cm3 0.9-0.95
After vulcanization    

Tensile strength at Kg/cm2 break at 23 oC  (N/mm2)

400 (40)
  Elongation at 23 oC, % >50

Dry to touch on DRY cement,  hours



Application of main membrane, hours

  Adhesion to cement, mPa >4















Clean the surface using a high pressure washer, if possible. Remove oil, grease and wax contaminants. Cement laitance, loose particles, mould release agents, cured membranes must also be removed. On non porous surfaces use HCl acid or/and Viacal. Apply with brush or roller depending  on the surface to be primed at a consumption of 50-200 gr/m2. Ensure primer has cured before applying main membrane/sealant.


Can  be kept  for 12 months  minimum in the original unopened pails in dry places and at temperatures of 5-25oC. Once opened, use as soon as possible.


Contains volatile flammable solvents. Apply in well-ventilated, no smoking areas, away from naked flames. In closed spaces use ventilators and carbon active  masks. Keep in mind that solvents are heavier than air so they creep on the floor.