A new Biosafe anti-microbial masterbatch based on silane rather than silver is said to provide good protection in extruded or injection molded applications. Jean Sirois, general manager at compounder RTP’s color division, the supplier of these masterbatches, says the silane-based technology renders plastics inherently anti-microbial at a more cost-effective and faster-acting rate than competitive silver-based additives. Additionally the masterbatches do not discolor, tarnish, or yellow applications, which he says can be a problem with anti-microbials based on silver or triclosan. “The active ingredient in these anti-microbial masterbatches only needs to be at a 0.25-0.5% loading in the final product to be effective,” says Sirois. “These masterbatches work by physically puncturing and rupturing the cell wall to inhibit microbial growth.” Conventional anti-microbials kill by leaching into a cell, where they are metabolized and interfere with critical life processes. He claims this can cause microorganisms to mutate and adapt, thereby becoming resistant to the anti-microbial. The masterbatch is FDA-listed as a modifier to medical devices. It is available for use in polyurethane, polyester, acetal, polycarbonate, nylon, vinyl, thermoplastic elastomers, and polybutylene terephthalate. In certain cases they may also be suitable for inclusion in ABS, polypropylene and polyethylene. RTP Co., Winona, MN; +1-507-454-6900; www.rtpcompany.com