Solvent Based Oligomeric Siloxane Water Repellent Product.Dubond's HydroShield S Waterproofing is a silicone concentrate that is based on silane / siloxane. It is colorless,hence maintains natural color of the substrate. Dilute solutions of hydroshield s in organic solvents serve as high-quality general purpose water repellents for impregnating and priming mineral and highly alkaline substrates.