702 K-Prep (Self-priming base coat over Kynar coated metal)
702 K-Prep (Self-priming base coat over Kynar® coated metal)
KARNAK 702 K-Prep is a 100% acrylic elastomeric co-polymer emulsion, specifically designed as a primer for improving adhesion to weathered Kynar® coated metal roofing. When applied to a suitably cleaned, weathered Kynar® coated metal roof and coated with a durable acrylic elastomeric base coat such as 404 Corrosion Proof Base Coat and finish coat such as 535 QS Enviro-Lastic, 501 Elasto-Brite or 529 Renu-White, the coating system can extend the life of the existing roof. The technology used in 702 K-Prep imparts very good adhesion and resistance to blistering over a surface that traditionally has been difficult to bond to.
- VOC: 37 g/L
- 0.5-0.5 Gallons per 100sf**
This is intended as a general guideline only, coverage can vary based on many factors.
Elastomeric Roof Coating Systems that use 702 K-Prep primer are ideal for use over Kynar® coated metal roofs that have been weathered at least four years.
Preparation & Application
Weathered Kynar® coated metal roofing surfaces accumulate dirt over time and must be cleaned prior to coating with 702 K-Prep. It is particularly important to effectively clean ponded water areas where greater accumulations of dirt can occur. For optimal adhesion and water resistance, water alone is insufficient to clean weathered Kynar® coating properly. Suitable liquid cleaners such as 799 Wash-N-Prep Roof Cleaner can be spray applied over the entire surface followed by a thorough power washing. Power wash roof surfaces using a pressure of 2500 to 3500 psi with a wide fan tip. All residual cleaning agents must be removed; otherwise they will interfere in the adhesion of 702 K-Prep. When using liquid cleaning solutions, please refer to the specific product label and MSDS for safe handling information and proper use instructions.
Mix lightly prior to application of the primer. 702 K-Prep may be applied by brush, spray equipment or roller.
BRUSH / ROLLER APPLICATION:
Brush/roller application should be done applying the primer evenly over the surface.
Utilize a standard paint spray pump or airless spray pump. Equipment manufacturer should be consulted for more complete information. Spray application should be done with a 50% over-spray pattern.
Apply 702 K-Prep over the surface at the rate of 0.5 gallon per 100 sq. ft. Allow 702 K-Prep to dry 2 – 4 hours before applying 404 Corrosion Proof Base Coat or selected finish coating. All applied primer should be coated over the same day for the best inter-coat adhesion. Coverage will vary depending on the surface to be coated.
Caution/Care of Tools
Do not apply when rain is imminent. Coating must be dried before exposure to water. Store in a heated room and keep container covered when not in use. Do not thin. Keep out of reach of children. Avoid prolonged contact with skin. Dispose of in an environmentally safe manner. Cover air intakes during application and while drying.
COLD-PROCESS SYSTEMS AND COATING, EITHER EMULSION OR SOLVENT BASED, SHOULD ONLY BE INSTALLED ON DECKS WITH POSITIVE DRAINAGE. PER NRCA, (NATIONAL ROOFING CONTRACTORS ASSOCIATION, “THE CRI TERIA FOR JUDGING PROPER SLOPE FOR DRAINAGE IS THAT THERE BE NO EVIDENCE OF STANDING WATER ON THE DECK 48 HOURS AFTER IT STOPS RAINING.”
CARE OF TOOLS:
While material is still wet, tools may be cleaned with water. Dry coating can be cleaned with Karna-Klean or xylene or similar solvent, taking the necessary precautions when handling flammable materials.
Recognized by professional roofing contractors as the best quality product in the market.