Solvent-based sealers are widely used for outdoor concrete surfaces, which help to augment the color of the concrete and also protect the surface. In a solvent-based concrete sealer, unlike the water-based ones, the polymers do not exist as separate particles. The solvent and the polymer are mixed for a clear and continuous solution.
As the solvent evaporates from the sealer, the polymer chains get closer and they become intertwined eventually.
The concrete surface that has been sealed using a water- or solvent-based sealer appears glossy because, in both sealers, the polymer stays on the surface of the concrete. In the case of a solvent-based sealer, it wets the concrete surface and penetrates deeply into the surface and so the result is a glossier finish, which augments the color of the concrete below.
Solvent-based concrete sealers act as a protective top coat for the concrete surfaces and offer stain and chemical resistance. They are UV resistant, non-yellowing, and are available in various sheen levels. A solvent-based sealer has a greater penetration ability into the concrete as compared to a water-based sealer.
However, solvent-based sealers have a few drawbacks. These sealers have higher VOC content and are considered to be less environmentally friendly. Also, they are not recommended for use on interior surfaces and areas that have poor ventilation. Solvent-based sealers are not as cost-effective as the water-based ones.
The uses of solvent-based sealers include:
Solvent-based concrete sealers can be applied using airless or LPHV (low-pressure, high volume) sprayers or roller brushes. Low-pressure or pump-up sprayers are suitable for solvent-based sealers containing less than 35% solid content. Sealers containing more than 35% solids can be applied by using a lamb wool applicator, which is essentially a wool rag that is wrapped around a block of wood.
Avoid applying the solvent-based concrete sealer on rainy, humid, or foggy days. If it is very hot, then the application should be done during the cooler hours and when the concrete surface is in non-direct sunlight or shade. Ensure that the surface is free of moisture and completely dry, otherwise, it will interfere with the bonding and curing.
The sealer should be applied according to the coverage rate recommended by the manufacturer and you must not over apply the sealer. Over-application or too many coats of the sealer can cause the sealer to peel, bubble, and turn white.