Optical films and other functional films are expected to have promising prospects.

      Date: 2016 April 18, 11:45 AM

        Optical films are one of many types of functional films, composed of thin, layered dielectric materials that guide light beams through their interfaces. They are widely used in optical and optoelectronic technologies to manufacture a variety of optical instruments.
　　
　　This year, plastic films—especially functional film materials—are set to play a crucial role in emerging industries. These functional films boast outstanding performance, cater to highly specialized downstream markets, and hold vast potential for future applications. Key segments such as water treatment membranes, solar cell films, flat-panel display films, and thin films used in semiconductors and microelectronics are poised for significant growth. Moreover, the technology behind functional film materials comes with high barriers to entry, with the main challenges lying in formulation, process development, and equipment innovation. Among the various types of functional films, optical films and photovoltaic films stand out as the most promising options, given their substantial market potential and relatively lower technical hurdles.
　　
　　Optical-grade PET is the primary raw material for optical films, and diffusion films, brightness enhancement films, and other types of optical films are all processed based on PET pellets. Optical films are characterized by their smooth surfaces, with geometrically defined interfaces between film layers. The refractive index changes abruptly at these interfaces but remains continuous within each individual layer. Additionally, optical films can either be transparent media or optically absorbing media, and they may exhibit either uniform or non-uniform behavior in the normal direction. In practical applications, however, real-world films are far more complex than their idealized counterparts.
　　
　　Due to the high technological complexity of optical film technology—making it a technology-intensive industry with significant barriers to entry—the sector currently relies heavily on imports. However, several domestic companies are now poised to enter the optical film market, and their involvement is expected to significantly boost demand for optical PET films. Currently, production capacity for optical-grade PET films is predominantly controlled by companies based in Japan and South Korea; domestically, no Chinese enterprise has yet achieved large-scale manufacturing capabilities in this area. Among them, Dongcai Technology and Nanyang Technology are well-positioned to lead the way in breaking through these challenges.
　　
　　Photovoltaic thin films primarily include backsheet films and EVA encapsulant films. The backsheet film is mainly composed of fluoropolymer films and polyester-based substrates. Among these, fluoropolymer films have the highest technological barriers, and currently, no Chinese company has yet achieved industrial-scale production in this area. In contrast, polyester films are relatively more mature; domestically, products from Dongcai Technology and Changzhou Yuxing have already gained certification from major international downstream customers. As a result, the trend toward import substitution is becoming increasingly evident, with companies like Dada Southeast, Shuangxing New Materials, and Nanyang Technology also actively entering this promising field.