An epoxy resin mixture of compounds of the formula ##STR1## wherein Alk--represents a defined alkylene group,Ar--represents a defined arylene group, each Z independently of the other represents hydrogen or the group ##STR2## (derived from the reaction of a hydroxyl group with a monoisocyanate) and 50-500% of all Zs represent the group ##STR3## This mixture is suitable for the manufacture of flexible moulded articles having a high tear growth resistance.