Untreated plastic articles can be attacked by microbic growth causing unsightly discoloration, unpleasant odors and polymer degradation issues. Antimicrobial additives can be incorporated with plastic resins during compounding or as a masterbatch during molding and provide a biocide treatment to control microbes. Common microbes antimicrobials can be effective against include mold fungi, mildew fungi, algae, yeasts, other microbes. Multiple antimicrobial technologies are available which are compatible with wide variety thermoplastic resins. Bacteria, fungi, moulds and mildews are present in our every day environment. These microscopic organisms have adapted to colonise and thrive in almost all places on earth. Residual levels of many bacterial strains are of no consequence to human health, in fact they can help build a general level of resistance in the human immune system to infection and disease. Certain microbes are harmful to humans and if left unchecked will proliferate to cause infections and diseases. There is a particular need to control these in sensitive environments such as hospitals where acquired infections including MRSA can prove to be fatal. Microbes can also be responsible for a wide range of undesirable effects such as product deterioration and discoloration, malodour and food contamination to name but a few.

Staffordshire, UK based Wells Plastics has been involved in antimicrobial masterbatches for many years. Bactiglas technology is being successfully used in medical, healthcare and white goods applications with and has FDA, EPA and EFSA food contact registration and approvals. End applications include PE medical tubing and PVC floor tile, film, sheet, foams, fibres, tapes, coatings and many others. Antimicrobial additives provide an extra layer of protection when combined with normal cleaning procedures. Articles manufactured containing Bactiglas additive dispersions have been externally tested and proven to exhibit reductions in bacterial viable counts by as much as 99.9999% against controls. The product is a range of silver based antimicrobial additive masterbatches and powder dispersions. Silver has long been established as an excellent biocide however it is the unique nature of the Bactiglas microscopic glass delivery system which provides the products superior consistency and longevity of effect. Residual levels of atmospheric moisture combine with the hydrolytically reactive glass to release the silver ions at the surface of the component. Tests have shown that the Bactiglas additive continues to work for at least eight years with no reduction in the product’s antibacterial performance. It works rapidly to reduce the numbers of living bacteria on surfaces. Whilst test methods make it difficult to determine the precise speed of kill, independently gathered results have demonstrated significant reductions in live bacterial cell counts within one hour. The additive has successfully been incorporated into the following polymers: ABS, Latex, PP, Acetal, Nylon, PPS, Acrylic, PC, EVA, PE, PU, GPPS, PEEK, PVC, HIPS, PET Copolymers. Technologies to attack hospital infections are continuing to advance. Infinity Compounding Corp. is launching a new line of antimicrobial concentrates and compounds. The new Inhibit antimicrobial additives are based on silver functionalized clay and prevent growth of bacteria, fungus and other microorganisms in a variety of applications. It offers the ability to add antimicrobial functionality to any structural, lubricated, electrically active or colored custom compound, helping customers achieve a fully functional antimicrobial product. The technology allows silver/clay platelets to release to the surface of a molded or extruded part at a controlled rate to produce a uniform, long-term antimicrobial effect designed to last for several years. Current tests of the product's efficacy against Staphylococcus aureus indicate very strong antimicrobial activity at loadings as low as 1% by weight with no effect on color or surface appearance. Concentrates up to 25% nominal additive loading are available in many engineering resins, including polypropylene, polyethylene, ABS, polyarbonate, PC/ABS, nylons, PBT, polyacetal, polyetherimide, PES, fluoropolymers and PEEK. Applications that can benefit from INHIBIT's functionality include medical, sports and recreation, office accessories, household goods, commercial lavatory and personal care items.