Application of a protective or decorative coating is the final step in many repair programs. A pleasingly uniform appearance can be provided for patched areas, while at the same time reducing the effects of weather or other deteriorating forces. In the refurbishing of sound structures, thorough cleaning followed by the application of a suitable coating may be all that is necessary to make a building look like new. This article lists some of the most commonly used paint systems which have merit for application to concrete. All are identified by generic names and include their advantages and disadvantages for use on concrete. However, the rapidly expanding technology of the paint industry in an atmosphere of increasing governmental and environmental regulations brings continuing changes. To keep up to date, a knowledge of current documents is required, supplemented by a working relationship with reputable, technically capable coatings suppliers.
The many decorative barrier coatings available today may be considered in two groups water based paints and solvent based paints. The solvent based paints may be further divided into single-package coatings such as the common alkyds, acrylics and vinyls, and two-component systems which include some of the maximum performance coatings. The latter form their hard-tile films through a chemical reaction and have properties approachable only by oven-baked systems.
Coatings, their attributes and limitations "cataloged" in this article include: latex emulsions, water-based Portland cement paints, alkyds, chlorinated rubbers, phenolics, acrylics, oil-modified urethanes, vinyls, urethane prepolymers, catalyzed epoxies, epoxy esters, two-component urethanes, and polyesters.