A composition of at least partially masked isocyanates. The isocyanates are masked by at least two different masking agents, selected such that in the octanol test at 110 C., the ratio: D=percentage in equivalents of masking agents unblocking first at 110 C./percentage in equivalents of masking agents unblocking last at 110 C., is greater than 4/3, advantageously greater then 1.5, preferably greater than 2. When a masking agent comprises a phenol function as a masking function, it does not comprise a COOH function.