Range of Application

• Primer for dry, damp or wet, open-pored mineral substrates
• Special primer for oily and wet substrates
• Additional barrier for oily or damp substrates as adhesive agent for coatings
• Resin screed according to EN 13813
• High-yield scratch primer
• Adhesive agent between existing and new concrete

Properties

• Epoxy-based primer
• Very low viscosity
• Water reactive
• Compatible with oil/moisture
• Slight residual tackiness
• Resistant to frost and de-icing salt
• Total solid

Application

• Application brushing, rolling, with rubber squeegee or trowel

WEBAC_® 4270: primer especially designed for floors contaminated with oil – prior oil removal is not required

WEBAC_® 4270 is a clear, non-emulsifying, unfilled and very low viscosity primer based on epoxy resin. Special feature: WEBAC_® 4270 can be applied to wet surfaces and open-pored oily substrates without removing the oil from the substrate beforehand. This is possible because it cures to form a viscoplastic to rigid material which stands out due to its water reactivity and good oil compatibility. WEBAC_® 4270 is also suitable as primer for wet surfaces. The product also serves as mortar resin, primer for mortar screed and for scratch coats. 

Free pores on the substrate’s surface are a prerequisite for the use as primer on oil contaminated floors. If you are uncertain whether free pores do or do not exist, it is absolutely necessary to carry out a test application in order to verify adhesion. WEBAC_® 4270 can be applied directly to very oily or greasy substrates while these are still damp after cleaning by means of hot water or steam cleaning. 
 

Contact with water and moisture accelerates the reaction of WEBAC_® 4270

Thanks to its very low viscosity and its water reactivity the material has a good wetting effect on the substrate and ensures excellent material distribution. WEBAC_® 4270 is capable of binding at least 15 % of water into the fresh mixture without any emulsion or bubble formation and of binding oil components from the open-pored interfacial area. These special properties ensure good penetration of the material. They also lead to a firm anchorage on dry, damp, wet and open-pored oily mineral substrates. When mixed with water or when applied to damp or wet surfaces the reaction is accelerated. This also speeds up the material’s curing process.

Substrates primed with WEBAC_® 4270 must always be scattered with stoved quartz sand (grit size: 0.1–0.3 mm, 0.3–0.7 mm or 0.7–1.2 mm). Exception: the primed surface is overcoated with a WEBAC coating system immediately after curing – within 24 hours after the application. The topcoat can be applied after allowing the coating to dry for at least 3–4 hours. In the event of very oily surfaces, WEBAC_® 4270 must have fully cured before applying the topcoat. The product's workable life amounts to approx. 20 minutes at 20 °C. It depends on the material quantity used and the temperature of the material. Optimum reactivity and workability are obtained at temperatures between 15 °C and 23° C. 

At 15 °C to 18 °C temperature of the building structure, WEBAC_® 4270 is dust dry and accessible to pedestrians after 24 hours. It has fully cured after two to three days; the product cures without shrinking.

If WEBAC_® 4270 is applied at high air humidity, steam condensate may be bound on the still liquid surface. This may lead to slight matting of the surface which has no impact on the material’s properties though.