IPC Main Group
C01B 21/00 Nitrogen; Compounds thereof
Introduced: September 1968
Last revised: January 2006
Classification Context
- Section:
- CHEMISTRY; METALLURGY
- Class:
- INORGANIC CHEMISTRY
- Subclass:
- NON-METALLIC ELEMENTS; COMPOUNDS THEREOF
Related Keywords
NITROGENother inorganic compounds of NITROGEN
6 direct subcodes
Child Classifications
Navigate with arrow keys, Enter to open
- C01B 21/02 Preparation of nitrogen
- C01B 21/04 Purification or separation of nitrogen
- C01B 21/06 Binary compounds of nitrogen with metals, with silicon, or with boron
- C01B 21/08 Hydrazoic acid; Azides; Halogen azides
- C01B 21/082 Compounds containing nitrogen and non-metals
- C01B 21/2 Nitrogen oxides; Oxyacids of nitrogen; Salts thereof
Top Applicants
Top 10 applicants by patent filingsfor class C01, 2013–2023, worldwide · Source: EPO PATSTAT
- CHINESE ACADEMY OF SCIENCES 5,794
- SINOPEC (CHINA PETROCHEMICAL CORPORATION) 3,286
- LG CHEM KR 2,689
- BASF (BADISCHE ANILIN & SODA FABRIK) DE 1,669
- CENTRAL SOUTH UNIVERSITY 1,531
- KMUST (KUNMING UNIVERSITY OF SCIENCE AND TECHNOLOGY) 1,252
- SUMITOMO METAL MINING COMPANY JP 1,073
- ZHEJIANG UNIVERSITY 1,061
- PANASONIC INTELLECTUAL PROPERTY JP 1,058
- PANASONIC INTELLECTUAL PROPERTY 1,038