Mechanism of silver technology used in antibacterial powder coating
For the present study inorganic antibacterial agent silver type is used. Five different types of silver additives are tried. The silver additives used is a composite of active silver ions, sodium ions and other ions (e.g. Zn). In some additives silver is embedded into a base material such as zeolite & glass matrix etc.
Silver ion is a natural inorganic antibacterial agent which is effective in fighting against bacteria, fungi& moulds. Silver ion is generally preferred for its
a. Bacterial resistance
b. Environmental compatibility/ compliance
c. Thermal stability
d. Effective life expectancy
e. It can be used for both indoor and outdoor applications.
Silver ion inhibits the process of cell division by which the bacteria replicates. The action of silver additive is based on the slow and continuous leaching of super fine silver ions that interact with the metabolism of the microorganisms in various ways. Moisture in the air accelerates the property of ion exchange process by which silver is released at a continuous rate and maintaining an antibacterial surface. In presence of moisture the zeolite pumps out silver ions in exchange for sodium ions from the environment. As the environment becomes more humid bacterial growth would be more, the zeolite discharges more silver ions thereby long term protection is ensured. Antimicrobial action of silver comes from the chemical properties of its ionized form Ag+. When microbes come in contact with antimicrobial powder coating surface, Ag+ is released accordingly to the surface of the treated product to inhibit the bacterial growth.