Mitsubishi Plastics, Inc. (head office: Chuo-ku, Tokyo; president: Hiroshi Yoshida) has successfully developed and mass produced a heat-resistant grade of its CARBOLEADER™ carbon fiber-composite roller used in film, printing, and paper and other manufacturing machinery that is suitable for use in high-temperature furnaces.

Equipment to process and convey web* is installed in high-temperature processing furnaces and drying furnaces used in the manufacturing processes of web, and processes to coat, apply surface treatments (e.g. vapor deposition), and laminate. Under high temperatures, however, the rollers tend to increase the runout due to uneven thermal expansion. Conventionally, under high temperatures the large runout of the rollers would cause uneven processing of web (e.g. non-uniform coating thickness) and conveyance issues (e.g. zigzagging, wrinkling, and patchy stretching due to uneven tension). These issues were a stumbling block for making web-production lines wider and faster. There was thus strong demand for the development of a roller with low runout under high temperatures, in order to resolve these issues.

The new heat-resistant grade of CARBOLEADER™ carbon fiber-composite rollers developed by MPI has an outstanding feature: its rotating performance in high-temperature furnaces of 100 to 200℃ is nearly identical to its room-temperature performance. As an example, in a mass-production lot of several hundred 3-meter long rollers, the runout at room temperature will be no more than 0.05 mm, and the performance will be nearly equivalent or better under conditions of a furnace temperature of 150℃.

The base materials of MPI's carbon fiber composite rollers are carbon fiber reinforced plastics (CFRP), with a pitch-based carbon fiber (product name: DIALEAD™) as the reinforcing fiber. DIALEAD™ has the following features: (1) it has a coefficient of thermal expansion of nearly zero; (2) its weight is two thirds that of aluminum; and (3) its Young's modulus (stiffness) is three times that of iron. CARBOLEADER™ carbon fiber-composite roller is assembled by Sunray Co., Ltd. (head office: Shiroi-shi, Chiba; president: Masanobu Yamanaka), one of Japan's leading dedicated roller manufacturers, using that company's high-precision roller processing technologies accumulated over many years.

This heat-resistant grade was only possible through MPI's design of a roller structure optimized for high-temperature furnaces using its CFRP structural analysis and design technologies, combined with Sunray's even more developed roller-manufacturing technologies. It enables more precise and faster web conveyance and processing, increasing web width, higher quality, improved yields, and lower loss. It will help improve the productivity of high-functionality films for such applications as LCD televisions, photovoltaic cells, and secondary batteries.

This grade is also expected to contribute greatly to the establishment of a "roll-to-roll" process, which is an essential technology for creating printed electronics (an expected growth area), some representative examples of which are flexible displays, flexible photovoltaic cells, and flexible chips.

Heat-resistant grade of CARBOLEADER™ carbon fiber-composite roller

*Long and flexible materials, such as paper, films, metallic thin films, and thin sheets metal, are called “web”

■Inquires regarding this material should be directed to the
	Public Relations Section, General Administration Dept., Mitsubishi Plastics Inc. TEL: +81-3-3279-3800