Gelest, Inc., Morrisville, Pa., supplies the coatings market with BIOSAFE silicon-based antimicrobials which prevent deterioration and discoloration caused by fungi, prevent algae growth and inhibit the growth of odor-causing bacteria. Leading the development, marketing and science of Biosafe antimicrobials, Donald J. Wagner II, Gelest/Biosafe technical marketing manager is a keen observer of the biocides market. Coatings World discussed with Wagner his views on the nature of the market, its direction, key takeaways for paint manufacturers, and Gelest’s involvement.

Coatings World: Did the biocides market see growth in 2015/16? What is the outlook for 2017 and beyond?
Donald Wagner: Yes, the market appears to be growing due to the trend toward zero- VOC products and the increased use of water-based formulations in paints, coatings, adhesives, and machining fluids. The side effect of the shift to zero-VOC solutions is that they harbor the growth of microorganisms and have increased the demand for antimicrobial agents in these segments.

Coatings World: Where are the areas of focus for the biocides market (water treatment, food/beverage, wood preservation, etc.)? 

Wagner: Some areas of focus are: water treatment; sanitizers and disinfectants; paints, coatings, and adhesives; textiles and fracking fluid preservatives.  Water treatment and sanitization is a growing business because of emerging markets and the increased need for hygiene. 

Coatings World: What are some of the environmental considerations for the biocides market?
Wagner: Given the need for compliance with U.S. EPA, the EU BPR, and the like, the environmental considerations of biocides suppliers and paint producers coincide. A biocide should have low-to-no acute dermal, eye, and oral toxicity, and low to no acute toxicity and irritation if inhaled. In addition, a biocide needs to be non-sensitizing and non-mutagenic.  It needs to be stable, with minimal degradability over a coating’s in-can service life. Traditional biocides worked by leaching poison, like heavy metal or a polychlorinated phenol.  This was marketed with a petri dish test that showed a “zone of inhibition” or a halo around the treated article (perhaps a paint chip) and touted as evidence of effectiveness. Now leaching is considered a negative. Leaching means the active is migrating into the environment or person, becomes depleted and is delivering non-lethal doses to microbes, which can cause resistance. Bound, non-leaching actives (like the silicon-based products Gelest makes) stay put, and the mode of action is a surface phenomenon where nothing is transferred to the cell or environment. Paint and coating formulations ideally use an antimicrobial that doesn’t migrate, leach, form toxic metabolites, or bio-accumulate.

Coatings World: What considerations should formulators make when choosing a biocide/fungicide?  

Wagner: First, the formulation should perform its task while having low impact and toxicity, for health and the environment.  Different products target different organisms. Formulators should choose a biocide/fungicide that targets the organisms they need to kill, whether it be bacteria, fungi, algae, or even yeast. Formulators should also consider and choose biocides or fungicides with modes of action that do not promote resistant microbes.

Coatings World: What are some of the more popular formulations, for example, halogen compounds, etc.? 

Wagner: For paint preservation, popular actives are IPBC (Iodopropynyl Butyl Carbamate (IPBC) and OIT (Octylisothiazolinone), IPBC is a broad-spectrum water-soluble biocide/fungicide in the carbamate family. OIT is a derivative of isothiazolinone and is also a broad-spectrum biocide/fungicide.  But neither of these actives are bound and non-migratory. The silicon-based antimicrobials, sometimes called the silane quats, are of interest and being tested in many coatings applications for their safety and non-leaching nature. Gelest is the only company that makes a truly zero-VOC silicon-based active and has 4 EPA registrations.

Coatings World: What are the latest technologies being developed for biocides for paint and coatings?
Wagner: The industry is developing unique combinations of active ingredients and new ways of encapsulation to deliver controlled or slow-releasing actives. Bound actives like the silane quats perform well as a surface treatment, are non-migrating, and have extremely low toxicity. Efforts to incorporate these into hygienic coatings are underway.  
 
Coatings World: What new products has your company launched for this market?
Wagner: The high cost of regulatory compliance and safety testing, and the drawn-out process for product approval is restricting companies from introducing new antimicrobial agents. Gelest has ushered its keystone antimicrobial polymer, HM4100, through the regulatory gauntlet and is targeting August of 2017 for approval of use on food-contact surfaces and filtration of potable water.  Gelest foresees food-contact as a high growth area for its antimicrobial products in the next 3-5 years.