COMPOUND HAVING ISOCYANATE FUNCTIONALITY, PREPARATION THEREOF AND USE THEREOF IN A PROCESS FOR PREPARING A COATING

摘要

The compound of the invention, having an average isocyanate functionality of greater than 2, results from the reaction of a (poly)isocyanate having an average functionality of greater than 2, with the compound X comprising a function B(H)_n or B'(H)_n' where n is equal to 1 or 2, n' is equal to 1, 2 or 3, H is a labile hydrogen and B denotes O, S, N, N being a primary or secondary nitrogen, -C(=O)-O, -C(=O)-N, or else the groups O=P(O)₂; O=P(O)OR₁; O=P(O)₃; O=P(O)2 OR₁; O=P(O)-OR₁, R₁ denoting an alkyl or aralkyl radical, and B' denotes -SiR₂R₃R₄, R₂, R₃ and R₄ representing oxygen, an alkyl radical bearing a function that is reacted with the (poly)isocyanate, or an aralkyl, aryl, -O-alkyl or -O-aralkyl radical, X being, in addition, a cycloaliphatic, aromatic or heterocyclic compound or a particle of a crosslinked polymer; and with the proviso that, when B denotes a secondary nitrogen and X is a cycloaliphatic compound, X is then a compound having at least two rings; the reaction being carried out with a compound X/[compound X + (poly)isocyanate] weight ratio of at most 50%. The invention also relates to a composition of the hardener type which comprises at least one compound of the above type. The compound or the composition of the invention can be used in the preparation of a coating of the paint or varnish type.