Thermosetting binder comprising an optical brightener

摘要

Aqueous binding agent (A) comprises: (1) a polymer or its mixture obtained by radical polymerization of 5-100 wt.% of ethylenic unsaturated compound, ethylenic unsaturated carbonic acid, dicarbonic acid and/or dicarbonic acid anhydride (which together are called acid monomers); (2) alkanolamine with at least two hydroxyl groups; and (3) a yellowing inhibitor. An independent claim is included for the controlled crosslinking of the aqueous bonding agent comprising: crosslinking the polymer and alkanolamine by increasing the temperature and determining the yellowing tone of the obtained product; determining the quantity of yellowing inhibitor necessary to compensate the yellowing tone and adding the determined quantity to (A); and subsequently crosslinking (A) by increasing the temperature, where the duration of the crosslinking reaction is controlled by coloring the crosslinking product.