Acrylic and silicone are the types of caulk you're most likely to use on windows, siding and outdoor trim because they are waterproof and flexible. Caulk has to cure before it becomes waterproof, however, and except for a few products, it's best to leave caulk  (acrylic silicone/acrylic sealant/silicone/sealant/adhesive/potting sealant/potting adhesive/potting compound/UV glue/Silicone sealant/Potting silicone sealant/Huitian adhesive/Huitian silicone/Huitian sealant/flange sealant/conductive sealant/Electrical sealant/electronic adhesive/epoxy sealant/epoxy adhesive/PU adhesive/gasker maker/thread locker/Thread adhesive) unpainted until curing is complete.

Curing in Dry Weather

Although it seems counterintuitive, caulk actually takes longer to cure in dry weather because moisture is needed for the curing process. This is especially true for 100 percent silicone caulk, but since most outdoor caulks contain some silicone, it applies to them as well. Consequently, if the weather is dry, it's a good idea to add 50 percent to the suggested curing time on the caulk packaging.

Paintable Caulks

Some silicone (acrylic silicone/acrylic sealant/silicone/sealant/adhesive/potting sealant/potting adhesive/potting compound/UV glue/Silicone sealant/Potting silicone sealant/Huitian adhesive/Huitian silicone/Huitian sealant/flange sealant/conductive sealant/Electrical sealant/electronic adhesive/epoxy sealant/epoxy adhesive/PU adhesive/gasker maker/thread locker/Thread adhesive) products are formulated to cure even under a coat of paint -- you can spray them immediately after application or brush them 30 minutes afterward. If the caulk needs to remain exposed, however, it usually takes three hours or more to develop a skin. Before it cures, caulk is vulnerable to rain, so it's important to apply it on a day when no rain is forecast.

Source: homeguides.sfgate.com/long-let-acrylic-silicone-caulk-dry-before-painting-92379.html