PROCESS TO HYDROPHOBIZE CEMENT-FREE MORTARS

摘要

The present invention provides a process to hydrophobize a mortar which is essentially free of cement, comprising the steps of mixing the mortar with an additive and water and subsequently allowing the mortar to cure, wherein the additive contains a component which is a rosin, a rosin derivative, a mixture of a resin with a rosin, or a mixture of a resin with a rosin derivative, wherein when the softening point of the component is higher than 60°C, the curing step is performed at a temperature that is not lower than the softening point of the component minus 20°C and when the softening point of the component is 60°C or lower, the curing step is performed at 40°C or lower, and wherein the rosin and/or rosin derivative have an acid number of at least 50 mg KOH/g, and when the component is a mixture of a resin with a rosin, or a mixture of a resin with a rosin derivative, the resin at 23°C and pH 7 has a water solubility of about 5 g/l or less and a Brookfield viscosity of less than 20,000 mPas, measured at 23°C and 20 rpm. The invention also covers an additive as well as a pasty and a dry mortar composition.