. . "The substituent in the monovalent hydrocarbon residue which may have a substituent, shown by R5 includes a halogen atom such as a chlorine atom, a fluorine atom, a bromine atom and in iodine atom, a lower alkyl group such as a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group and a tert-butyl group, a lower haloalkyl group suc" . . . .