Protectosil® SH is a mixture of ethyl esters of different polysilicic acids for the consolidation of construction material.
Scope of Application
Protectosil® SH is used to deposit silicic acid formed as a result of complete hydrolysis. The resulting silicic acid bonds well to many mineral, inorganic substrates, such as natural stone, brick or terracotta stones. The deposition of a thin SiO2 layer improves the chemical and thermal stability and mechanical properties. In the case of porous mineral substrates Protectosil® SH is used for stone consolidation. Depending on the kind of natural stone Protectosil® SH is used in specifically developed formulations as a silica source. Protectosil® SH is immiscible with water, so hydrolysis therefore requires a co-solvent such as ethanol, methanol or white spirit. Mineral acids, ammonia, titanates or tin compounds are suitable as catalysts. Directions for use: The substrates to be treated should be air-dry and clean in order to ensure deep penetration of the active ingredient. During application the outside temperature and the temperarture of the substrate should be within the range of 5 °C to 40 °C. The material should not be applied if there is strong wind or if it is raining. The treated area should be protected against rain for at least 2 days after application. Protectosil® SH is applied by spraying (e.g. airless spraying guns). For small areas a wash bottle can be used. For the consolidation to be successful the stones or masonry must be totally penetrated by Protectosil® SH. Therefore a wet-in-wet application until the material is not adsorbed anymore is recommended. The amount of application depends on the absorbency of the substrate, which means between 0,5-1,0 l/m2. In most cases a solvent-based formulation of Protectosil® SH is applied. The determination of the penetration depth helps to check the sufficient amount of application. Excess ethyl silicate can be washed away from the surface using wihite spirit or alcohol. Non-absorbent substrates such as, for example, glass, wood, plastic, and metal cannot be treated with Protectosil® SH. Glass, wood and metal are not attacked by Protectosil® SH. Neither are most plastics used in construction. Therefore, covering is normally not necessary. To make it sure we recommend to carry out a test. In the worst case, product not absorbed by the substrate may react with atmospheric moisture to form a greasy, glossy silicone resin film, which can easily be removed if cleaned immediately using conventional cleaning agents, or alcohol. All equipment and containers must be clean and dry. After use they can be cleaned with any organic solvent (methylated spirit, petrol or thinners). In order to check the right amount of application and the success of the consolidation it is recommended to prepare a sufficient large test area. If a hydrophobizing agent should be applied as well, it is recommended to wait 2 weeks after the application of Protectosil® SH. The following water repellents are applicable: Protectosil® BHN, Protectosil® 40 S and Protectosil® 60 SK.