concrete release, whether in powder or liquid form, plays two roles on a stamped project: it prevents stamping mats from adhering to concrete and thereby disturbing the imprint texture, and it provides color accents that enhance the integral or dry-shake coloring system, creating an antiquing effect.

Powdered release agents, such as Walttools Powder Accent release, are applied just prior to stamping using a brush and flicked onto the concrete surface. They contain iron oxide pigments that not only act as a concrete releasing agent but provide a secondary tint for contrasting color in stamped or textured concrete.

Liquid releases, on the other hand, are sprayed on the concrete surface with a pump sprayer. Liquid release can also be tinted, but contractors have to add their own pigment a day or two before they plan to use it to make sure the color is well mixed and will dissolve properly.

When using tinted release, it’s important to fog the stamp mats and concrete just ahead of where you are going to apply the product. If you don’t, the release may evaporate before you get to that area and could contaminate the next color application with dark splotches or clumps of color.

Water-based emulsions are the latest product generation of concrete release and are used for reasons of health, safety at work and environmental hygiene, as they do not emit any toxic fumes during spraying. They are very easy to handle and, unlike products based on mineral oils, are fully compliant with the new regulations for immediate demolding of standard formwork. They are especially suitable for precast plants.