(b)[ The abstract shall contain a concise summary of the matter contained in the specification and the summary shall indicate clearly the technical field to which the invention belongs, technical advancement of the invention as compared to the existing knowledge and principal use of the invention excluding any speculative use and where necessary, the abstract shall contain the chemical formula, which characterises the invention.] [Substituted by Notification No. G.S.R. 523(E), dated 16.5.2016 (w.e.f. 2.5.2003).]