Abstract
Keywords: Statistics Patents Catalysts Filters Applicants
The field of exhaust gas aftertreatment systems of internal combustion engines has been always under great and rapid development, due to the great interest it has been shown by governments, public and private institutions and consumers towards a more reliable, more powerful and cleaner transportation means. This is boosted by national and international laws that force the engines manufactures to increase their research activities in the sense to meet more and more challenging objectives related to reliability, fuel consumption and exhaust gas emissions. The most reliable way to measure this research activity is through the number of patent applications that are submitted to different patent offices in the world. This paper offers a thorough statistical analysis of the innovation trends in Europe, USA and Japan in the field of exhaust gas aftertreatment systems of internal combustion engines during the last 10 years. It demonstrates which technical fields (e.g. NOx absorption and reduction catalysts, particulate filters, electronic control and diagnosis of exhaust gas aftertreatment systems etc.) are the most active, who are the most important players and which country attracts the highest number of applications. Subfields of certain technical fields are also analyzed. The technical fields discussed are chosen according to the International Patent Classification (IPC) scheme. These technical fields include catalysts and particulate filters in general, NOx adsorption and selective reduction catalysts, , desorption and regeneration techniques, combined catalyst and/or filter systems, electronic control and diagnosis of exhaust gas aftertreatment systems.