In 1990–1995 period, the PDLC field has been the subject of an early progress, predominantly by few worldwide licensees mentioned in the Introduction. However, in this period, due to unrealistic strategies, overestimated market forecasts and high price issues, the global PDLC market did not grow according to expectations. During 1995–2002 period, due to patent disputes between Raychem and KSU, the field experienced a period of recession. Although by 1989, Raychem had consolidated its patent position in the USA, in 1991, KSU filed oppositions to Raychem’s filed patents in Japan and Europe. However, by 1995, Raychem’s patents had been granted in these territories, and, consequently, KSU lost its patent own validity in Japan and Europe. This episode had resulted in reduction and even closure of commercial activities by KSU’s licensees in Japan and Europe. Namely, Asahi Glass and Ajinomoto closed their commercial PDLC activities in Japan, but Snia (FIAT) continued its R&D programme in Europe.
In the USA, 3M and Polytronix continued their commercial activities because the former had licence from both Raychem and KSU and the latter, who had a worldwide licence from KSU, located its commercial activities in Taiwan under its Polytron subsidiary. The resurgence of PDLC industrial and commercial activities begun when the original Raychem and KSU patents had been expired in 2002 and 2005, respectively. Since this period, the field had witnessed rapid growth in industrial and commercial activities by appearance of new PDLC film and glass producers in the worldwide scene. In the past decade, due to increase in competitions, gradual reduction of production costs and product prices, increased expertise in glazing techniques, as well as extensive market promotion campaigns have resulted in a surge of market demands and continuous growth of PDLC business worldwide. The current ongoing globalisation of the technology is mainly due to the industrial awareness that R&D, product, application and business diversifications are the realistic strategies for market acceptance and growth of PDLC technology.