Research on water production around the world began in earnest only at the beginning of the 20th century. Before then, people were able to obtain sufficient clean water through natural purification processes. However, along with industrialization and rapid population growth, it became more and more difficult to secure safe drinking water.
Former US President John F. Kennedy is known for having declared the importance of seawater desalination technology during his time as a Senator. It is likely that he foresaw the worsening global water problem and its significant impact on the world's industries and economies. Along with the Apollo space mission, President Kennedy established seawater desalinization as a national project as soon as he took office in 1961, and helped accelerate the corresponding technology development.
Toray took notice of these developments, and in 1968 began R&D into reverse osmosis (RO) membranes. In 1980, the Company succeeded in commercializing RO membranes that create the ultra-pure water necessary for semiconductor manufacturing. After that, Toray went on to take the lead in fields such as seawater/brackish water desalination, wastewater reuse, and water treatment for various kinds of industrial processes.
Toray is one of the few manufacturers in the world that has developed a full range of water-treatment membranes on its own. The Company has four types of membrane technology: RO membranes, NF (nano-filtration) membranes, UF (ultra filtration) membranes, and MF (microfiltration) membranes. Through the optimal combination of these technologies, Toray is able to meet various water treatment needs worldwide.

An RO membrane is a high-performance water treatment membrane that separates pure water from water concentrate containing impurities such as saline matter. Only pure water is able to penetrate through the membrane, which blocks salt and other substance at the molecular level. Compared to conventional and widely-used thermal desalination systems that extract pure water by boiling seawater and cooling down the distilled water, the RO desalination method only requires one quarter the amount of source water, and less than one fifth the energy such as heat and electricity. As a highly efficient technology for freshwater production in terms of energy and resources, RO desalination is expected to contribute greatly towards global environmental protection.
As of 2007, the accumulated reduction in CO₂ emissions resulting from the use of Toray's RO membranes installed around the world amounts to approximately 9.4 million tons. Assuming a continuation of the current rate of new RO desalination plant construction and switchover from thermal desalination, the resulting savings in CO2 emissions is expected to be approximately 100 million tons by 2020.

Toray's RO membranes have been installed in a total of 100 plants around the world, mainly in large plants in 26 countries and regions. Based on the quantity of membranes sold to date (including those used for purposes other than seawater desalination), Toray's technology is responsible for producing 15.5 million cubic meters of water per day, or enough water to supply the household needs of about 65 million people (as of March 31, 2009).
Toray is a founding member of the Global Water Recycle System Association Japan (see Column article) for the development and worldwide application of water recycling systems based on Japan's outstanding technology and expertise in this area. This recent movement is creating new opportunities for helping to solve the world's water issues.
Given the realities of global warming and population growth, soon it will be difficult for human beings to continue relying only on natural water resources. Therefore, it is necessary to make effective use of limited global water resources by producing clean water through advanced technology.
Toray Group will continue to expand its water treatment business based on its unique technologies, in order to contribute to solving global water resource issues.