Pecora AC-20 5 gallon
AC-20 is a pure acrylic latex sealant for general purpose interior and exterior
caulking in architectural applications where slight to moderate movement is anticipated. Formulated with the highest quality ingredients including a silicone additive for greater adhesion and weatherability, AC-20 is completely compatible with premium-grade latex and oil paints and will not stain adjacent
surfaces. AC-20 has superb color stability and resistance to ultraviolet rays, ozone and airborne contaminants. It is mildew resistant and has United States Department of Agriculture acceptance for use in meat and poultry processing plants. In addition to the substrates listed above, Pecora AC-20 5 gallon is compatible with polystyrene, polyurethane, cork, foamed and fibrous glass and gypsum board.
AC-20’s elastomeric properties make it an excellent sealant for caulking interior concrete joints, hollow core ceiling and floor planks, window and door frames, vinyl, aluminum, steel and plywood siding, sheetrock, baseboards and bathroom and kitchen fixtures. It may be used to grout marble and ceramic tile, repair mortar joints, and, under controlled conditions, to bed insulated glass units and storm windows.
Contact area must be clean, sound and free of contaminating substances such as oil, grease, asphalt, tar, etc. Priming is not generally required. Dampness but not saturation or standing water in porous substrates can be tolerated.
Joints greater than 3/8” (9 mm) should be filled to within 3/8” (9 mm) of the surface with either polyethylene or polyurethane backer rod, preferably of a non-gassing, non-absorbing type. Use a diameter that will compress about 25% when installed. In joints too shallow to take backer rod, use a bond breaker tape to prevent three-sided adhesion.
Although the freezing point of Pecora AC-20 5 gallon is considerably below 32° F (0°C), and the sealant can withstand five freeze-thaw cycles, for best performance protect it from severe cold and apply above 40° F (4°C) to lessen the possibility of frost in the joints. Fill joints completely and tool lightly to insure full contact to both sides of the joint and present a smooth surface. As with any waterborne product, the cure time is dependent on ambient conditions. Low temperatures or high humidity will extend cure time, while higher temperatures or low humidity will accelerate the cure.
Sealant may be painted 30-45 minutes after application with quality
grades of latex or oil paints.
Water may be used to remove excess sealant from substrate and
clean tools before cure; after cure, sealant must be removed with mechanical means.