Most authorities agree that the most feasible and economical means of curing concrete properly is the spray application of a liquid membrane curing compound. These materials are sprayed onto the finished concrete as soon as the final troweling has been completed. A suitable liquid membrane curing compound is capable of maintaining a minimum of 95 percent of the original moisture content in a concrete mix. It is also economical and easy to apply.
The liquid membrane method of concrete curing inhibits the loss of mix water by forming a protective membrane of the surface of the slab as soon as it is applied. This membrane is seldom more than 2/1000th of an inch thick and it is capable of maintaining a minimum of 95 percent of the mix water present in the concrete mass at the time of application. The curing compound is effective up to 28 days and will then gradually dissipates without leaving a stain or discoloring the concrete surface.
There are, primarily, two basic types of non-pigmented liquid membrane concrete curing compound: wax resin and all resin types. The wax resin type is suitable for use on concrete that will not subsequently be painted, tiled or treated in any manner. The wax contained in the material remains on the concrete surface and hampers the adhesion of future paint or mastic. The all resin type is ideally suited for the curing of those areas where there will be a subsequent treatment applied to the concrete, since it leaves no adverse residue on the concrete surface. In fact, the residual film of the all resin type is harder than the wax resin and provides more resistance to abrasion. It also prepares the concrete surface for future treatment. Both types are void of pigmentation and are available with a dissipating fugitive dye to aid in easy application.