Abstract: A novel benzxoylurea derivative represented by the formula (I) described below, its production and an insecticidal and/or acaricidal composition containing it as an active ingredient: ##STR1## wherein R.sub.1 is a chlorine or fluorine atom, each of R.sub.2 and R.sub.3, wherein may be the same or different, is a fluorine or hydrogen atom, R.sub.4 is a chlorine or hydrogen atom, R.sub.5 is a halogen atom or a methyl or trifluoromethyl group, and X is an oxygen or sulfur atom.
Abstract: A novel process for preparing asymmetrical thioureas having the formula ##STR1## is disclosed, which comprises reacting RNH.sub.2 with CS.sub.2 in the presence of a base to produce RNHCS.sub.2 .crclbar. followed by reaction of the RNHCS.sub.2 .crclbar. with R.sub.1 R.sub.2 NH in the presence of a catalytic amount of a base to produce the desired product.