Aging peculiarities of special silicate dispersion paints
The technological properties of silicate dispersion paints stored for one year, as well as the technical and performance characteristics of their coatings were analyzed.
One-year storage was found to increase paint viscosity by 15–30%, i. e. its mixing became slightly worse, but the paint was still fit for use. When during storage the viscosity increases by more than 50%, it becomes difficult to mix the paints, and the physical and technical properties of coatings are significantly worse. Paints stored for different time were tested. The majority of indicators, in particular water permeability, abrasion resistance and wet scrubbing resistance, were found to have deteriorated. However, some of the coating properties, e.g. vapor permeability, improved (the Sd index decreased by 10–20%). The quality of paint coatings is characterized by the index of the water vapor permeability rate multiplied by the water permeability rate (Sd × W24), and it must be kept at the minimum level. Upon improving the water vapor permeability of coatings by 20%, this index increases very slightly.
The technological properties of silicate dispersion paints stored for one year, as well as the technical and performance characteristics of their coatings were assessed in a certain scale of scores which reflected the quality of individual indices, and the summarized scores characterized the general changes of paint quality.