According to the company's slogan "Materials can change our lives", Toray of Japan, through its Torayca carbon fiber and carbon fiber reinforced plastics (CFRP), is contributing to energy saving and reducing greenhouse gas emissions. The company's polyacrylonitrile (PAN) grade carbon fiber composite material market has about half of the market share, making it a market leader.
At present, PAN-based CFRP has become the mainstream of the industry. It was first developed by the Osaka Government Industrial Research Institute (GIRIO), which subsequently became the Kansai National Institute of Advanced Industrial Science and Technology (AIST). These efforts were created by a research team led by Akio Shindo in 1962, and the material holds a basic patent.
Yasuo Suga, senior vice president of Toray, said his company started its own efforts during the same period. He said that this was the form of the internal development team developing acrylic fiber (the raw material for CFRP), which began research in the area in 1961.
The first obstacle to be overcome by Toray is to develop the best raw materials. Suga said that after a series of trial and error, developers found that PAN can be used as a raw material for the copolymerization of hydroxyethyl acrylonitrile (HEN), thereby improving the performance of the material.
Suga said that in 1970 Toray started large-scale projects aimed at developing carbon fiber technology for mass production. At that time, Japan did not have any high-temperature furnaces capable of withstanding 2,600–2,800°C production. Therefore, Toray’s production process caused the carbon fiber itself to burn and was unable to provide a suitable product.
To develop a better manufacturing process, Toray signed a cross-licensing agreement with United Carbide Corporation (UCC), which was already producing carbon fiber at the time, but used rayon as the raw material for production. Therefore, Toray trained UCC on the use of high-performance raw materials, and UCC trained Toray on its own manufacturing process. The agreement enabled Toray to successfully commercialize carbon fiber in 1971.
Since 1972, the technical improvement of Toray's carbon fiber has largely benefited from the application of this material in fishing rods. The typical sweetfish rod at that time was about 8 meters long and weighed about 900 grams. Suga said, but Toray developed a plate with carbon fiber on the outside and glass fiber on the inside, and began to sell it to fishing rods.
With the weight reduction of this new material, Suga continued, many fishing rod manufacturers began to apply it immediately to their products. These companies subsequently demand lighter and lighter materials every year. Therefore, Toray continued to develop new grades, and finally reached a level of 10 meters long fishing rod weighing only 180 grams, lighter than newspapers. Since 1973, the company's carbon fiber has also been used in golf shafts.
After early development efforts, Toray continued to establish its own business in the sports and leisure markets in the 1970s, while also attracting customers in the automotive and aviation industries.
Yasuo Suga said that the company's success in 1975 was because Boeing adopted the company's T300 grade carbon fiber as the Boeing 767 spoiler and other auxiliary structural materials. Boeing solved the problem by purchasing carbon fiber with Union Carbide Corp., which signed a cross-license agreement with Toray.
Subsequently, Toray plans to use its carbon fiber as the main material of the aircraft wing and tail, when the wing and tail are made of aluminum. However, Boeing told Toray that the company's carbon fiber will be tested and used as the main material only if it can increase tensile strength and elasticity while being 30% lighter than aluminum.
In response, Toray developed the T800H grade. Compared with the existing T300 grade, the strength is increased by about two times, and the elasticity is increased by 20% to 30%. Boeing also has a requirement that the material must be able to withstand the impact of birds colliding with the aircraft.
Suga said that even if impacted by birds, the performance of aluminum will not be affected in any way. However, carbon fiber-reinforced composites have seen cracks in the resin after being subjected to this impact, so improving this becomes the key.
Suga explained that this problem was solved by dispersing the newly invented thermoplastic particles throughout the thermosetting resin. The final material was adopted in the tail and other parts of the Boeing 777 in 1996. This material allowed each aircraft to use approximately 7 tons of carbon fiber, while the 767 used approximately 1 ton of carbon fiber per aircraft.
For its next-generation 787, Boeing has decided to use CFRP in most parts of the fuselage, and finally adopted Toray’s new T800S grade for all these parts in 2008. Establish a new US carbon fiber production base.
At the same time, in the automotive field, the rise of electric vehicles has created a trend in which lightweight frames must be used. Therefore, people's demand for automotive CFRP will have further growth. But because this requires carbon fiber for mass-produced cars, the current cost is still too high. In order to achieve the current target cost, Suga said that it is necessary to reduce the production cost and accelerate the molding speed of the automobile CFRP.
In terms of materials, Suga believes that large tow carbon fibers must be used here, which can reduce costs compared to other forms of materials. He also added that manufacturing methods will require further innovation. So in 2014, Toray acquired Zoltek, a major producer of large-scale tow carbon fiber, for 58 billion yen. Recently, Toray Corporation acquired the Dutch TenCate Advanced Composites, which is the manufacturer of aircraft CFRP, which further strengthens its position as a market leader.
A little more expertise
A lot of knowledge can be gained from the history of the company's carbon fiber development told by the president of Toray. For example, in the early development of T300 carbon fiber, T300 technology breakthrough was finally achieved by exchanging high-temperature heat treatment technology with UCC, so high-temperature heat treatment technology is the same as high-quality raw silk. Important (click for further reading). In 1975, Toray’s entry into the aviation industry was the key to its rapid development. For example, the success of T800 carbon fiber research and development was to meet Boeing’s strength and modulus improvement; and in order to improve the impact resistance of CFRP, Toray invented granular thermoplastic Resin toughening technology.
With the low cost of carbon fiber and the trend of carbon fiber application in the automotive field, Toray Japan decisively acquired Zoltek, and developed the latest low-cost carbon fiber industrial grade product Z600 (read the original Japanese Toray's latest product Z600 carbon fiber), and Expanded production capacity. In order to further enhance the company's composite manufacturing capabilities, TenCate Advanced Composites was acquired, and serialization operations have made Toray a stronger company.