Is a water-based product that has been designed to stop the oxidation process resulting from the use of our act-COR oxide activator or act-COR Gel. This emulsion, which has a milky look, leaves a whitish appearance on the surface after it has been applied, which in turn will become transparent once it has dried. After about 45 minutes, the surface will be dry to the touch, although it should be left for 24 hours if you intend to subsequently varnish the surface.

In addition to stopping the oxidation process that has been initiated by using act-COR, bp-COR is essential if you want to either reduce oxide carry-over as much as possible or if you intend to further treat the COR-TEN © steel with varnish. This is because it prepares the surface for the varnish coat, providing excellent adhesion. However if you intend to leave the COR-TEN © steel without varnish and it’s going to be located outside, then we recommend the use of bp-COR Extreme instead, as this product is designed to be used as a final coat, providing the COR-TEN © steel with additional protection against atmospheric agents.


No, it’s a water-based product.

bp-COR is similar to a water-based varnish, but has different application characteristics, a different drying speed and when used with corten steel, delivers improved sealing characteristics.

No, if the product is applied undiluted, it has greater hardness and durability, especially if you are going to apply stop-bath as the final layer.

This is not its intended usage; bp-COR is a water-based product and because of this, can leave small oxide particles during the drying and sealing processes.

Using stop bath as a finishing product (i.e. the final layer) can allow the treated metal to be installed in areas exposed to rain and temperature ranges of between 40-50° C and it will still be in good condition five years later.

Yes, there are different application techniques, either using a roller, a gun (turbine) or a sponge. There are courses available that provide instructions on how to apply the products. Specifically, training on how to correctly apply bp-COR, is among the most recommended.

Depending on whether the steel you are treating is located outside or inside, applying varnishes gives an “extra” to the final finish. In interior applications, varnishes will produce a finish with different shades; outdoors, the varnishes will add hardness to the stop-bath layer.

Yes, it can make a big difference. This is due to the fact on vertical surfaces, the rain drops will leave marks and, more importantly, once dry, will results in areas with rust entrainment and be more exposed. It is not advisable to apply bp-COR if rain is likely during its application. The metal to be treated must be completely dry and remain free from moisture.

This action should always be done by opening the pores of the product already applied, by sanding the surface using a fine grain abrasive and applying the product, if possible, diluted with water (50%).

It is difficult to give a precise answer, as it would be necessary to carry out multiple tests with the various products that are available. We focus on making these tests between our own products. Therefore we do not recommend using other manufacturer’s products in combination with our own.