Polymer dispersion of synthetic resins and admixtures. Water-based. Ready-mix for immediate use. For priming of highly and medium absorbent mineral surfaces, above all gypsum-based mineral surfaces (machine plasters, gypsum-cardboard panels, anhydride screed) and cement as well as lime-cement plasters prior to laying coverings and tiles. It reduces the water absorption capability of the mineral surface and consolidates it, thus enhancing the adhesive strengths of subsequently applied mortars, adhesives and levelling compounds. Regarding the absorption capability of the substrate it can be used as a concentrate or mixed with water in the ratio 1:1.