Non-Silver Technology for PP, ABS, and PC Resins Could Help Resist Microbes
A new, non-silver technology offers “built-in-the-polymer” protection against infection-causing pathogens. Evermoin, developed by Lotte Advanced Materials, boasts a 99% bacterial growth inhibition rate for pathogens such as Staphylococcus aureus and E. coli and also inhibits the growth of fungi. The product maintains its antimicrobial capabilities in a variety of environmental conditions such as light and moisture as well as daily scratches, with little changes in color.
“Our material is not silver-based for a few reasons,” said Andrew Ji, business development manager at Lotte Advanced Materials USA Inc., in an interview with MD+DI. “Silver is very costly, and in order for manufacturers to guarantee antimicrobial properties, they have to add a lot of nanosilver materials. This will increase the overall cost,” he said, noting that some manufacturers tend to minimize the use of silver for this reason, but in doing so, the antimicrobial performance of the products may become unstable.
Ji explained that another issue with using silver is the time and difficulty involved in processing the substance. When manufacturers use nanosilver, they have to make the resin first and then go through a separate process of adding the nanosilver materials, he said, adding that this additional step not only adds time, but also cost.
By contrast, Ji said that Evermoin requires no additional processing. “Our materials are all-in-one virgin resins, which means antimicrobial additives are already included within the resin.”
Evermoin offers long-lasting antimicrobial performance compared with nanosilver materials, without the color degradation that can happen with silver when it oxidizes. “In the case of silver-based antimicrobial agents (including nanosilver), black lines are visible because of silver oxidation due to high temperature and oxygen contact during the process,” Ji said. “In addition, silver-based antimicrobial performance deterioration can occur by water and light (in real-life usage setting),” Ji said.
Evermoin maintains its antimicrobial properties even when there is a damage, such as a scratch, to the surface, Ji said. It was tested by putting it in a water bath for 24 hours and rubbed 100 times with a cloth or tissue.
Lastly, Ji claims that Evermoin is safe to use because it does not contain nanoparticles. Scientists have expressed the need for more data on the human exposure effects from silver nanoparticles. It is also compliant with ISO 10993-5 and ISO 10993-10 standards and compliant under FDA specification 21 CFR 175.300, according to the company.
Possible medical applications include medical housings, equipment, and accessories, according to the company.