A sealant’s tack-free time is the point in the curing process when the product or bead stops being sticky. This is essential because the tack-free time is the moment when beads become generally resistant to picking up dust and/or dirt from the environment. A shorter tack-free time ensures a better looking, much cleaner aesthetic to the finished project.

Some products will have no tack at all once it reaches a final cure.  They might have a completely smooth, glossy finish.  However, others may possess varying levels of tack or texture that can remain throughout the life of the install.  And while the sealant remains slightly sticky long-term, at this point it has not fully cured and can still be deformed and result in a broken seal.

Depending on what kind of job a contractor is doing, the importance of paint time for a sealant will vary. The paint time refers to when the surface of a bead has cured enough that’s its shape and strength can withstand the pressure of a paint brush, and layer of paint product, without negatively affecting its ability to fully cure. Contractors need to be aware that some construction sealant technologies like silicones are not paintable.

Many sealant manufactures will list the paint time of products right on the tube. It’s also recommended for contractors to run a test bead to see how specific formulations hold up during the painting process. There are important differences between painting certain sealants. For example, hybrid sealants don’t have to be fully cured before they can be painted - which keeps things moving and saves contractors significant time on the job site.

The cured time for a sealant is when the product has reached its final chemical state and performance throughout the entire depth of the bead.  It will remain in this state for the lifetime of the product. Depending on the specific formulation, cured time for sealant can be anywhere from a day to a couple of weeks. Sealants that take longer to fully cure have the potential to cause delays on the job site. Most manufacturers will have the cure time for a sealant listed on the tube itself and on the product’s tech data sheet.

The full cure time of a sealant formulation is also impacted by temperature and humidity.  Temperature ranges are provided by manufacturers to allow the product to fully cure with maximum performance benefit.  Some products have a wider range than others, but contractors should ensure their local climate conditions lie within the recommended values to lower the risk of a sealant failure. Sealants with larger cure time temperature ranges give contractors more flexibility to get jobs done on time and year-round.

Contractors who want a construction sealant that has a superior combination of adhesion and flexibility should consider OSI QUAD MAX. It’s a next generation sealant that can be painted in one hour, has a 24-hour fast cure, skins over in 17 to 20 minutes, and become tack-free in 15 hours. Learn more about how QUAD MAX brings a superior combination of adhesion and flexibility to the job site.