Frequently Asked Questions
What are the requirements on antibacterial testing and washing durability?
Dow recommends the use of a very specific antimicrobial test that is becoming the standard for all testing of antimicrobial treated articles. This test is based off other standard tests such as the AATCC100, ISO20743 and the JIS L1902. This method is available as a Dow Internal Standard Test Method. Initially, treated samples will usually demonstrate >99.9% bacterial reduction using these methods. Dow, however, requires at least 90% reduction after laundering when using these tests.
How can my company meet the requirements for SILVADUR?
The application instructions for SILVADUR technology are very clear for both exhaustion and pad applications. Simply follow these application instructions with the recommended addition levels (based on the weight of the goods); you should have no problem meeting microbiological performance parameters.
What is the efficacy of properly treated products?
Independent, third party microbiological laboratories have confirmed that samples properly treated with the SILVADUR antimicrobial technology will easily demonstrate greater than 90% bacterial reduction after 50 home launderings.
What is the spectrum of antimicrobial activity of the SILVADUR technology?
This historical use of silver as an antimicrobial agent is well documented and has been shown to have a very broad spectrum of activity. Silver ions are extremely effective at destroying both Gram + and Gram – bacteria. With the controlled release of silver ions found only in the SILVADUR antimicrobial polymer system, all bacteria and fungi are extremely susceptible to this technology.
How many launderings can SILVADUR treated textiles withstand?
Using several different industrial standard test methods, the SILVADUR antimicrobial technology has been shown to be effective over the “life of the goods”. Laboratory testing demonstrated excellent antimicrobial activity after 50 launderings, which exceeds most expectations for ‘life of’ textile products.
What antimicrobial tests are appropriate for this technology?
The Dow Internal Standard microbiological test is the most reliable and effective test method that can be used to measure antimicrobial effectiveness. Other methods that have been used to measure the antimicrobial effectiveness include but are not limited to: AATCC100, JIS L1902, ISO20743, ASTM E2149
What antimicrobial tests are NOT appropriate for this technology and why?
The SILVADUR polymer technology ONLY releases silver at the surface of the treated fabric. Unlike particle based silver technologies that release both ionic silver AND silver laced particles into the surrounding area, SILVADUR antimicrobial only releases silver ions at the surface. This means that NO “Zone of Inhibition” will be seen with SILVADUR treated samples. Test methods that determine the performance of an antimicrobial based on the size of the ZOI from a treated article are not appropriate for the SILVADUR technology. The SILVADUR mode of action will not create a ZOI. These methods include AATCC147, ISO20743 (Qualitative Method) and other agar based protocols.
Can I measure the presence of the SILVADUR on my treated fabrics both at the mill and at retail?
Yes, Dow scientists have developed a method that will allow both the mill and the Brand owner to detect the presence of the SILVADUR technology directly on the treated goods.
What interference or compatibility issues are there with other textile additives?
No interference with other typical textile auxiliaries has been seen with the SILVADUR non-ionic polymer system.
Other antimicrobial agents can affect the “hand” or “moisture management” properties of the fabric. Will SILVADUR alter these properties?
Unlike Silane-quat polymers which greatly change the hydrophobic characteristics of the fabrics, the SILVADUR polymer has been shown to maintain, and in some cases increase, the moisture management properties of treated fabrics. There is no change in hand or drape of SILVADUR treated goods compared to untreated controls.
Silver particle antimicrobial agents are notorious for causing color problems. Why is SILVADUR different in this regard?
Silver particle antimicrobial agents act by providing a large supply of silver doses inside a particle structure. These particles can be released over the useful life of the product and become associated with the bacterial surface. The particles then release both metallic and ionic silver indiscriminately. The SILVADUR polymer system is NOT released from the surface and due to its “smart polymer system” will only release silver ions AT THE SURFACE OF THE TEXTILE. This means that no silver laden particles are released into the environment. And, due to the very low level of silver ions released, discoloration of the treated surface is NOT a factor.
Other antimicrobial agents need binders or excessive heat cures to obtain substantial durability. What other agents must I use if I want extend durability on my fabrics when using SILVADUR?
The SILVADUR antimicrobial system is an all-in-one polymer. The polymer system reacts with itself and with the surface to provide its own cross-linked polymer on the surface. This polymer system binds the silver directly and only releases the silver ions when needed. This unique polymer system requires NO extra binders and NO excessive heat cures to apply.
Do I need to License the SILVADUR name and if so, how much extra cost is associated?
Yes, using the SILVADUR name, brand or hang tags requires a License. DOW provides a royalty-free License for Licensees that utilizes the SILVADUR Quality Assurance Program.