Phthalate-free isocyanurate formulations

ABSTRACT - 601663 The disclosure relates low-monomer, low-viscosity, highly effective formulations made of isocyanate groups-containing isocyanurates and phthalate-free plasticizers, to the use thereof as adhesion promoters having improved adhesion for coating agents on the basis of plasticized polyvinyl chloride, and to coatings and coated substrates. Particularly disclosed is a process for producing the preparations comprising: (A) from 15 to 50% by weight isocyanurates containing isocyanate groups and (B) from 85 to 50% by weight of n- or isoalkyl monobenzoates, with the proviso that, (i) the isocyanurate containing isocyanate groups is produced through trimerization of a mixture of 2,4-diisocyanatotoluene and 2,6-diisocyanatotoluene and (ii) the total of all the percentages by weight is 100%, wherein the trimerization of the TDI mixture to give component (A) takes place in the temperature range from 40 to 140°C in the presence of plasticizer component (B) and the presence of at least one Mannich base functioning as catalyst, and as soon as the content of free TDI in the reaction mixture is below 1.0% by weight the trimerization is terminated through thermal decomposition of the catalyst or through addition of at least one catalyst poison selected from dibutyl phosphate or methyl toluenesulfonate, with complete or partial deactivation of the catalyst.