摘要 |
<p>The continuous or quasi-continuous process for lightening organic polyisocyanates with ozone-containing gas, the treatment of the organic polyisocyanate being effected with an ozone-containing gas which furthermore comprises at least one further inert and/or reactive gas can be carried out, according to the invention, in a stirred tank with connected storage tank, in a sieve tray column or in a packed column.</p> |