The ions attack harmful substances using the same mechanism as our bodies' own natural defenses. They can't be seen, but the air in your room contains pollen, allergens, mold, viruses and other harmful substances. In 1998, Sharp researcher Kazuo Nishikawa looked at the state of air purification technology at the time, and realized that the methods they were using had reached the limits of their effectiveness. Up to that point, air purifiers used filters to trap harmful substances. In the future, however, a new method of air purification would need to be devised if dust collection were to be improved, and he wondered if even that would be enough. Nishikawa was driven by the thought of the air in the room where his child slept filled with the droppings and remains of dead dust mites, as well as mold, viruses, and other harmful substances. Nishikawa shuddered at the thought of inhaling all of this as he slept, and decided that something needed to be done. A new approach had to be taken, and he was determined to make it happen.

Nishikawa and the heads of the research team at the time spent long hours in the lab searching for a solution. They soon came to the conclusion that filters were limited by the fact that they could only remove harmful substances that entered the filter in the first place. "In order to truly purify the air, it was necessary to develop technology to attack harmful substances in the air directly." During the brainstorming sessions that ensued, several approaches were considered. "We need some kind of substance that attaches directly to airborne microbes while they are in the air." Initially, Nishikawa considered ozone. This is because ozone is a very powerful oxidizer, and is known for its deodorizing and anti-bacterial properties. To be effective in the air, however, they would need to use a high density of ozone. In high densities, however, ozone becomes very toxic to people's health, making it almost impossible to use indoors. Another approach would need to be found. Around the same time, products that generate negative ions to aid relaxation were gaining in popularity.

Nishikawa considered using them for air purification, but after several experiments, negative ions appeared to be ineffective for use as a disinfectant. kanberra gel natural air purifierNonetheless, Nishikawa felt that something wasn't right. commercial air duct cleaning edmontonUpon closer examination of airborne microbes, he saw that some were positively charged, while others had a negative charge. honeywell large room hepa air cleanerPerhaps, when only negative ions are released, they simply repel the negatively charged microbes. If both positive and negative ions were released, could they cause some kind of reaction with both varieties of microbes? But which ions to use? There is such an enormous variety to choose from.

Which ions would have the needed effect? Nishikawa plunged into the research literature to find an answer. He began to wonder if our own immune systems might hold a clue. When bacteria invade our bloodstream, the germ-fighting white blood cells, attack the microbes and other foreign matter by releasing positive H+ and negative O2- ions. Could the same approach be taken against foreign matter in the air? A new approach to this challenge was taking shape. The results were exactly what they were looking for: when H+ and O2- ions were released into an enclosed testing chamber containing mold, viruses, dead dust mites and dust mite feces, and other allergens, the number of contaminants in the chamber decreased. At the same time, Nishikawa investigated whether the ions posed any health hazard for people. These ions are found in abundance in nature, and are the same ions we encounter in our daily lives. In addition, even at concentrations high enough to ensure disinfection, ozone concentrations were kept at less than 0.01 ppm, which is considerably lower than the standard figure of 0.05 ppm.

We found the type of ions that should be used and verified their effect. The actual reason why the ions purified airborne microbes was not yet known. Needing to know the answer, Nishikawa contacted every university and research institute he knew to propose joint research projects to examine this effect, but was unable to raise any interest. Discouraged, he was close to abandoning his work when good fortune smiled on him. Nishikawa had been actively participating in international academic conferences to share his findings and spread awareness of the positive effects that had been achieved, when received word that a German university was interested in studying his results. Once the two teams began working together, the mechanism behind the disinfecting action of the ions soon became clear. In simple terms, the mechanism works as follows: when H+ and O2- ions cohere around an airborne microbe, they combine to form a highly oxidizing OH radical. The OH radical extracts hydrogen from the proteins making up the airborne microbe's outer membrane sheath, without which mold and viruses cannot live.

In this way, by releasing H+ and O2- ions to purify the air from harmful substances, Plasmacluster technology was born. While Plasmacluster technology achieved the ideals that it had been designed for, it still needed to be proven to the world that the results were genuine. From the beginning of this project, Nishikawa had been seeking out research institutes to carry out cooperative experiments in order to gain more data to prove their conclusions. This was not a simple task, as performing experiments with harmful and possibly infectious agents carried a significant amount of risk. To conduct disinfection experiments on mold, for example, many institutions were approached before one was found that was willing. Furthermore, the number of research centers even capable of doing experiments directly on the viruses themselves is limited. Though discouraged, Nishikawa and his team continued to contact research facilities in Japan and overseas regularly. While they were desperately searching for partners, the Ishikawa Health Service Association agreed to work with them, and was able to provide data showing the effectiveness of Plasmacluster technology against airborne mold.

Soon, more data began coming in from other institutions, providing additional data for viruses, allergens, and other contaminants. As independent proof of the value of Plasmacluster technology continued to accumulate, Sharp began to apply this "academic marketing" as part of their product development strategy. By considering the health and environmental quality of our living space, developers are making new progress. "Be the first to develop a product that others will want to imitate." In 2000, Plasmacluster technology made its world debut, as equipped air purifiers went on sale. For consumers who were becoming increasingly concerned about dead dust mites, dust mite feces and other allergens, a purifier with such effectiveness was an instant hit. In 2008, nine years since the initial launch of Plasmacluster technology, Nishikawa's challenge is not yet over. "We don't plan on stopping at clearing rooms of airborne contaminants; we also want to remove the bacteria and odors that can attach themselves to your clothes," says Nishikawa.