NEWS RELEASE

Teijin Frontier Develops Eco-friendly Polyester Staple Nanofiberthat Reinforces RubberTokyo, Japan, April 11, 2022 --- Teijin Frontier Co., Ltd., the Teijin Group's fibers andproducts converting company, announced today that it has developed an eco-friendly
staple polyester nanofiber that offers excellent performance to reinforce rubber uses in
products including automotive tires, hoses and belts. Teijin Frontier will start production in
2023 and expects sales to reach JPY one billion (nearly USD 8.2 million) by the fiscalyear ending in March 2028.
Teijin Frontier, guided by its THINK ECO® environmental initiative, is striving to improve
its environmental value, including by developing greener materials and products forapplications ranging from clothing to industrial materials. The new staple nanofiber
matches the company’s increasing emphasis on solutions that help to easeenvironmental burdens.
Teijin Frontier will continue to expand the types of polymers that can be used for the newstaple nanofibers and continue to develop them for a wide range of rubber and resin
products such as tires, hoses and belts. The company will also promote the developmentof products that utilize recycled raw materials with the aim of reducing the environmental
burden.
The new staple nanofiber incorporates both polyester nanofiber and polyethylene
polymers, which are combined in Teijin Frontier’s proprietary sea-island composite crosssection. Different polymers are used for the "sea" and "island" parts to improve rubber
reinforcement. A polyester nanofiber with a diameter of either 400nm or 700nm is used as
the island as reinforcing material and the surrounding sea part is made with polyethylene,
which mixes easily with rubber. Compared to conventional products, mixing takes placeat the molecular level, which enables thousands of times more nanofibers to be evenly
dispersed in the rubber for equal or better reinforcing but requiring a relatively small
amount.

Sea-island composite cross section

The length of the new staple nanofiber is just 1mm or less, but the aspect(length-to-diameter) ratio is high thanks to the small diameter, which contributes toreinforcing. Further, the fiber’s short length prevents entanglement and twisting, andadditionally helps to disperse the fibers and rubber evenly. The fiber forms continuouslines or surfaces, rather than dispersed clumps. In actual use, the fibers rather than therubber absorb deformation stress, resulting in more durable rubber products.
Reference dataDiameter x LengthFiber Count(same weights)

Aspect Ratio(length / diameter)

400 mm x 0.5 mm(new nanofiber)

25,0001,250

700 mm x 1.0 mm(new nanofiber)

4,080

1,429

20 mm x 5.0 mm(conventional products)

1250

Since the new staple nanofiber exhibits higher reinforcing performance compared toconventional products, it can reduce the polymerization process. The shorter fiber
eliminates the need for surface treatment, which prevents the fiber from intertwisting likecotton. Both attributes help to reduce environmental load, including less greenhouse gas
emissions.
When used in automotive tires, the new staple nanofiber increases elasticity and reduces
resistance, so it should help to improve fuel efficiency and reduce noise. It is also
expected to improve the elastic modulus and durability of automotive hoses and belts,
which has been difficult to achieve until now.
Staple fibers are used to strengthen rubber in products required to withstand repeated
deformation and abrasion. Conventionally, this has been achieved by adjusting fiber
strength and length, the latter generally to between several millimeters and several tensof millimeters. Increased length, however, leads to entanglement and twisting when thefiber is kneaded into the rubber, which reduces strength due to less efficient fiber
dispersal. Meanwhile, growing environmental concerns are raising demands for reduced
molecular weights and surface treatments to reduce greenhouse gas emissions.
About the Teijin Group
Teijin (TSE: 3401) is a technology-driven global group offering advanced solutions in thefields of environmental value; safety, security and disaster mitigation; and demographic
change and increased health consciousness. Originally established as Japan's first rayon

manufacturer in 1918, Teijin has evolved into a unique enterprise encompassing threecore business domains: high-performance materials including aramid, carbon fibers andcomposites, and also resin and plastic processing, films, polyester fibers and products
converting; healthcare including pharmaceuticals and home healthcare equipment forbone/joint, respiratory and cardiovascular/metabolic diseases, nursing care andpre-symptomatic healthcare; and IT including B2B solutions for medical, corporate andpublic systems as well as packaged software and B2C online services for digitalentertainment. Deeply committed to its stakeholders, as expressed in the brandstatement “Human Chemistry, Human Solutions,” Teijin aims to be a company that
supports the society of the future. The group comprises more than 170 companies andemploys some 20,000 people across 20 countries worldwide. Teijin posted consolidated
sales of JPY 836.5 billion (USD 7.7 billion) and total assets of JPY 1,036.4 billion (USD9.5 billion) in the fiscal year that ended on March 31, 2021.
Press Contact
Corporate Communications
Teijin Limited
pr@teijin.co.jp