Structural properties and inter-organizational knowledge flows of patent citation network: The case of organic solar cells

This paper identifies the structural properties of a technological knowledge network and the role of major organizations in the network, and analyzes actual contents of technological knowledge flows in terms of organization-technology linkage, by targeting the field of organic solar cells (OSC). Network analysis and matrix analysis methods are used to achieve these purposes. The results show the small-world effect exists in the technological knowledge network of OSCs, and the organizations with high betweenness centrality lead the technological knowledge flows. We also find technological knowledge in classes 136 and 313 flows relatively actively in key organizations׳ network of OSCs. This means that technological knowledge regarding photoelectric batteries and electric lamp and discharge devices is mainly circulated between key organizations and indicates that the electronics or display sector will become a major consumer for early commercialization of OSCs. The target of analysis in this study is a patent citation network in the field of OSCs. Since we did not analyze all scientific publications, we cannot conclude that the results represent the entire flow of technological knowledge in that field. However, given that little attention has been paid to empirical studies of technological knowledge flows at the organizational level, this study makes an academic contribution by directly analyzing technological knowledge flows between organizations and presenting new taxonomic method based on centralities. The analytical process and methodology of this study, which include analysis of the structural properties of technological knowledge networks, matrix analysis and taxonomical grouping, and analysis of technological knowledge flows between key organizations, will be usefully applied to the analysis of technological knowledge networks in other fields.