Pure silver mesh material "MG Net" silver ion elution test report

We conducted a test on April 10, 2020 as follows to see how the silver ion concentration changes when 0.1g of pure silver mesh "MGnet" is added to 1 liter of ultrapure water and sodium hypochlorite solution (a solution simulating tap water). Please refer to the attached sheet for details of the test content.

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１． Test item：

The sample "MGnet" is made by twisting nylon fibers with electroless plating of silver onto the surface into threads and forming a coarse honeycomb net. Nylon 70%, pure silver 30% (weight ratio).

２． Testing Facility：

Osaka Industrial Technology Research Institute (Headquarters/Izumi Center)

３． Exam Content：

Pure silver mesh "MGnet" silver ion elution test 1

４． Test Overview：

"MGnet" was added to "ultrapure water" and "water to which sodium hypochlorite at the upper limit of the water quality standard for tap water had been added," and the silver concentration (amount of silver ions) was examined after 1 hour, 4 hours, 8 hours, and 24 hours.

５． Test sample：

MGnet0.1g（Silver surface area approx 63c㎡）

６．Test Solution：

1 liter of ultrapure water, 1 liter of sodium hypochlorite solution (simulating tap water)

７． Test results: see table below

Test result data For more details

８． Test Report：

It was confirmed that the silver ion concentration in both the ultrapure water and the sodium hypochlorite solution exceeded 50 ppb (0.05 ppm) one hour after the MGnet was added.

The chlorine (Cl) and silver (Ag) in sodium hypochlorite (NaClO) bond very easily and quickly become silver chloride (AgCl). The silver chloride precipitates, and then the silver ions are dissolved. The reason why the concentration of silver ions is higher in sodium chlorite solution than in ultrapure water is presumably because a solution with more impurities (sodium and oxygen) than pure water promotes ionization.

Since the antibacterial effect of silver ions is exerted at a concentration of 10 ppb (0.01 ppm or more), it can be considered that effective disinfectant water was produced within one hour from both ultrapure water and sodium hypochlorite solution (tap water). When sodium hypochlorite (tap water) is used, silver and sodium hypochlorite combine to form silver chloride, which consumes silver and reduces the total amount of silver ions eluted, shortening the effective period of use of MGnet.

The amount of silver ions generated is proportional to the surface area of ​​silver. When 50 times the amount of MGnet (5g) was added in elution test 2, the silver ion concentration exceeded 100ppb (0.1ppm) in 1 minute.

Silver ion elution test 2

As a result of the above, our MGnet has about twice the surface area of ​​silver compared to the surface area of ​​the material, and the surface area of ​​0.1g of silver is about 63cm2. When added to 1 liter of water, effective silver ion water is generated within 1 hour. Silver ion water with a concentration of over 10ppb has sterilizing, antibacterial, and deodorizing effects.

Medical Aid Co., Ltd.