Vinyl monomers containing blocked isocyanato groups were prepared in one step, by blocking the isocyanato group of 2-isocyanatoethyl methacrylate with phenol, propanone oxime, butanone oxime, benzophenone oxime or &-caprolactam, or in two steps, by blocking one of the two isocyanato groups of 4-methyl-I ,3-phenylene diisocyanate with phenol or &-caprolactam and the second group with 2-hydroxyethyl methacrylate. The I H NMR and the IR spectra of these monomers are discussed.