In the emerging strategic industries, the rare earth industry is developing rapidly. Rare earth is not only a key strategic basic material for the transformation of traditional industries, but also an indispensable strategic resource in modern industry. China has large reserves of rare earth resources, but the technology is on the low side. The purpose of this paper is not only to promote the development of rare earth industry in the new environment, but also to deeply analyze the development and changes of core technology in the middle reaches of rare earth industry. This paper uses Derwent Innovations Index which is a patent document retrieval system established by Derwent Publishing Company in 1951. This paper uses the patent data of rare earth application materials in the middle reaches of the rare earth industry from 1967 to 2016, as well as the methods of statistical analysis and scientific knowledge graph.
The conclusions are drawn from the following aspects: first, the analysis of the time trend shows that the number of patents from 1967 to 2016 is roughly in line with the exponential growth, and can be divided into three stages. The number of patent applications increased linearly from 1967 to 1991, decreased at first and then increased from 1992 to 2004. the overall trend was an S-shaped curve with a prominent lower part, and from 2005 to 2015, the number of patent applications increased at first and then decreased, and the whole was an S-shaped curve with a prominent upper part.
Second, based on the analysis of the countries and regions applying for patents, China, Japan and the United States are important components to promote the development of mid-stream technology in the rare earth industry. The patent research in the United States and Japan started earlier, the research period is longer, and mastered the core technology in the field of rare earth application materials. On the other hand, patent research in China starts late and the research period is short. The period from 1985 to 2002 is a backward period. Although China now has the largest number of patents, it has only increased in the past 10 years;
Third, through the analysis of patent applicants, it is found that patents are concentrated in the comparison of core applicants, that is, the core technology is only in the hands of a small number of people. The top 10 patent applications are well-known international companies, including China Petrochemical Corporation, Rhodia Group of the United Kingdom, Toyota Motor Co., Ltd., and so on.
Fourth, from the patent applicant cooperation network, we can see that the cooperation group is divided into two parts. The cooperative relationship between foreign companies is very close. Compared with the foreign research, the research on rare earth applied materials in China started relatively late, the early research is not mature, and the cooperative relationship between various research institutions is sparse.
Fifth, the analysis of hot technology shows that B01J-023/63、B01D-053/94、B01J-023/10、B01J-037/02 and other technical fields are in the core position in the map, and the density is high. It is found that J04-E04, J04-E11, N01Mub, N07-L02C, N03-A01, H06-C03 and other technical fields are in the core position in the map, and the density is high.
Sixth, by drawing the patent citation network, it is found that American patents are cited the most times. By extracting the main path of citation evolution, it is found that the core patents from 1967 to 1991 are US3702886A, US3930987A and so on. The main technical topics are rare earth hydrocarbon cracking catalysts instead of zeolites, crystalline zeolites for hydrocarbon conversion, rare earth oxides as catalysts for waste gas purification, etc. The core patents from 1992 to 2004 are EP507590A1, US5254519A, etc., which mainly studies the application of rare earth in catalysts, with emphasis on the catalysts used to purify waste gas, and the technical topics also include the application of rare earths in golf rubber and hydrogen storage materials; from 2005 to 2015, the core patents are US2005209026A1, WO2006043348A1, etc., most of the American patents study the application of rare earths in the manufacture of golf ball core. The patent quality of China′s research in the middle reaches of the rare earth industry has been greatly improved, mostly for the study of rare earth permanent magnet materials.
Seventh, by indexing the patent intensity of the evolution path, it is found that the patents that appear on the patent evolution path are not all core patents, but directly cited patents that appear in chronological order. Therefore, a more comprehensive algorithm should be adopted to find the main path of patent evolution.
Based on the increasingly prominent advantages of technological research and development, China should further increase investment, promote the maturity of existing technologies, and at the same time add new impetus to the continuous research and development of core technologies; the current economic shift period coincides with the timely optimization of the overall layout of the rare earth industry, so that the scientific and rational industrial structure has become a strong support for industrial upgrading, and the core technology has become a "new fuel" for industrial development. Our research institutions should cooperate extensively to promote the germination of new technologies and work together to promote technological development, and if necessary, it is also necessary to carry out international cooperation on the premise of ensuring national security; we should strengthen innovation systems and capacity-building to follow the international frontier development trend.
With the rapid growth of the number of patents in China in recent years, we should improve the quality of patents and innovate on the original technology. Nowadays, the field of big data also occupies a very important position, and big data′s mining technology is also relatively mature. It excavates the existing patent information more deeply and finds more reliable and predictable technical information. It can be regarded as a way to break through the technological blockade, so as to promote the high-quality development of the rare earth industry.
