Arrowhead Research Subsidiary, Unidym, Enters into Development Agreement with Nippon Kayaku to Integrate Carbon Nanotubes into Thin Film Solar Cells.

MENLO PARK, Calif. -- Unidym, Inc., a majority-owned subsidiary of Arrowhead Research Corporation (NASDAQ:ARWR), announced today that it has entered into a joint development agreement with Nippon Kayaku, to integrate Unidym's printable transparent electrodes into Nippon Kayaku's thin film solar cells. Nippon Kayaku Co. is a diversified Japanese chemical company with over $1.4B in 2007 sales that is bringing its global development and manufacturing capabilities to the rapidly developing thin film solar cell market.

According to Solarbuzz, an international solar energy research and consulting company, thin-film photovoltaic technologies hold great promise in the solar market and could contribute strongly to the industry's expected growth from $10.6 billion in 2006 to $18.5 billion by 2011.

Thin film solar cells require a transparent electrode material for optimal efficiency, and Unidym's carbon nanotube-based electrodes could offer substantial benefits over the materials currently in use, such as indium tin oxide (ITO).

"Unidym's products provide several advantages over ITO for solar cell manufacturers, including compatibility with high-volume, roll-to-roll manufacturing techniques, lower materials cost, and enhanced flexibility," said Art Swift, Unidym's CEO and President. "We expect our printable electrodes to significantly improve production economics for innovative solar companies like Nippon Kayaku and accelerate widespread adoption of solar power."

"Nippon Kayaku is delighted to be working with Unidym to integrate carbon nanotube-based electrodes into our thin-film solar cells," said Mr. T. Inoue, Group Leader of Nippon Kayaku's solar cell project. "We expect to be a technology leader in this important segment of the solar power market."

About Unidym

Unidym (www.unidym.com) is a leader in the manufacture and application of carbon nanotubes (CNTs), a novel material with extraordinary electrical, thermal and mechanical properties. Unidym provides bulk materials, CNT-enabled products and intellectual property to a wide range of customers and business partners. As a result of its recent merger with CNI, Unidym possesses a foundational patent portfolio that covers nearly every aspect of CNT manufacturing and processing, as well as multiple product applications.

Unidym is focused on the electronics industry where its initial products include transparent electrodes for touch screens, flat panel displays, solar cells, and solid state lighting; electrodes for fuel cells; and thin film transistors for printable electronics. Unidym is also pursuing a cross-industry partnership strategy to support the wide ranging applications of CNTs. Unidym's licensing program, technical expertise, and manufacturing facilities can enable partners to rapidly develop CNT solutions for their specific applications. Unidym is a majority-owned subsidiary of Arrowhead Research Corporation (NASDAQ:ARWR). For more information about Arrowhead, please visit www.arrowheadresearch.com.

About Nippon Kayaku

Since our founding in 1916, the Nippon Kayaku Group has expanded from a base in the fine chemicals business into a broad range of new fields, including explosives, dyes, pharmaceuticals, agrochemicals, functional products, catalysts, and automobile safety parts, with the goal of improving ourselves and aligning our business resources with the needs of the rapidly changing times.

For our future operations, we have positioned our functional chemicals business to focus on the areas of information and communications. We are also targeting the growing field of energy, where a number of Nippon Kayaku technologies can be applied. In energy, we are proceeding with development efforts, including collaborations, with related companies and universities that are aimed at commercializing dye sensitized solar cells, fuel cells, LED materials and other products that require a combination of multiple technologies, such as dyes, electrolytes, sealing materials, and adhesives.

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