A pseudotriangular layered platelet composed of silver 2-mercaptoethane sulfonate and its dual effects as pearlescent and antimicrobial pigments

Abstract

Pearls have been highly valued as gemstones for thousands of years because of their unique and fascinating colors. However, it was difficult to harvest pearls in large quantities in nature due to their scarcity. Thus, there has been a steady demand for the development of artificial pearlescent pigments, and substrate-based pigments composed of mica substrates with coated metal oxide layers were introduced in the 1960s. Although these pigments remain the most common pearlescent pigments up to date, they have no other functions except for the pearlescent effect. Herein, we present novel micron-sized particles which are layered platelets with a unique pseudotriangular shape (triangular with concave sides and a bifurcated vertex) and composed of antimicrobial reagents, silver cations, and 2-mercaptoethane sulfonate anions. These particles exhibit both pearlescent and antimicrobial properties owing to their structure (layered platelets) and constituents (antimicrobial reagents), respectively. An additional advantage of these particles is that they can be prepared in one-pot process through a precipitation reaction by simply mixing two aqueous solutions containing silver cations and sodium 2-mercaptoethane sulfonate anions. These particles can potentially be used as pigments requiring both pearlescent and antimicrobial properties in the pigment field.