# ONE PACK POLYURETHANE MAINTENANCE PRIMER RAINBOW PAINTS ## Product Code PU-700 ## Type Single-component transparent primer cured by moisture, formulated with polyurethane resin, zinc flakes, mica and rust conversion anti-corrosion pigments. ## Application Anti-corrosion & repair primer for steel frames, bridges, storage tanks, pipelines and all iron & steel products. ## Properties 1. Single-pack formula, easy construction, time-saving and labor-saving 2. Moisture-curing coating, applicable under high humidity environments 3. Low viscosity delivers excellent penetration into rust layers, fully sealing and tightly bonding rust surfaces to steel substrates 4. Suitable for steel surfaces without blast cleaning; only high-pressure water washing or hand tool derusted steel substrates 5. Superior resistance to chemicals, water and salt spray, passes 3000-hour salt spray test 6. Fast drying to shorten construction cycle ## Specification Data - Color: Brown, Grey - Hiding Power: ≥10 ㎡/L - Specific Gravity: ≥2.15 kg/L - Viscosity: 80~110 KU (25°C) - Drying Time - Surface dry: Within 30 mins - Hard dry: Within 3 hours (25°C) - Film Thickness: Wet film 120 μm, Dry film 60 μm - Theoretical Coverage: 8.33 ㎡/L, 3.88 ㎡/kg - Recoating Interval: Minimum 3 hours - Volume Solids: Above 50% - Thinner: NO.736 ULI Thinner - Thinner Dosage: 0~5% (including tool cleaning) or apply undiluted - Compatible Topcoats: ULI Topcoat, Rainbow Standard Topcoat, Long-Term Topcoat & Fluorocarbon Topcoat - Storage Stability: Minimum 6 months under normal storage ## Application Methods Brush Coating, Air Spray, Airless Spray ## Construction Precautions ⚠️ 1. Fully remove moisture, grease, dust and other contaminants from substrate surfaces prior to coating. 2. Use designated special thinner for dilution to avoid bubbles and pinholes. 3. Reacts with moisture in air to generate bubbles and gelation; keep can tightly sealed to isolate ambient moisture. Residual paint in cans can be diluted with small amount of NO.736 thinner and transferred into small sealed containers to prevent gelation. 4. Single pass wet film thickness exceeding 80 μm easily causes bubbling; control film build during application. 5. Recommended to finish construction within 3 days after opening the can. ## Note All data provided in this product datasheet are derived from internal laboratory test data for construction design reference only. Actual performance varies subject to different construction environments. This document does not constitute any legally binding warranty or statement from the manufacturer. Contact our technical department for clarification of any uncertainties.