Monitoring and Optimisation of Ag Nanoparticle Spray-Coating on Textiles.

An automatic lab-scaled spray-coating machine was used to deposit Ag nanoparticles (AgNPs) on textile to create antibacterial fabric. The spray process was monitored for the dual purpose of (1) optimizing the process by maximizing silver deposition and minimizing fluid waste, thereby reducing suspension consumption and (2) assessing AgNPs release. Monitoring measurements were carried out at two locations: inside and outside the spray chamber (far field). We calculated the deposition efficiency (E), finding it to be enhanced by increasing the spray pressure from 1 to 1.5 bar, but to be lowered when the number of operating sprays was increased, demonstrating the multiple spray system to be less efficient than a single spray. Far-field AgNPs emission showed a particle concentration increase of less than 10% as compared to the background level. This finding suggests that under our experimental conditions, our spray-coating process is not a critical source of worker exposure.