Novel bleach activator compounds derived from the reaction of isocyanic acid with selected nucleophiles

Laundry detergents commonly contain bleach activators that react with the perhydroxy anion produced from perborate or percarbonate anions to form activated peroxy compounds; these enhance bleaching and stain removal capacity especially at lower temperatures, hydrogen peroxide being an inefficient bleach below 60°C. The most commonly used activators are N, N, N′, N′-tetraacetylethylenediamine (TAED) and sodium nonanoyloxybenzenesulphonate (SNOBS) the former being used across Europe whereas the latter is used widely in the United States and Japan. This research studies the preparation of novel activator compounds which are carbamylated derivatives of selected nucleophiles using either solid or aqueous reactions of nucleophilic carboxylate anions with the highly reactive isocyanic acid entity derived from the acidification of sodium cyanate. The novel activator compounds were then assessed as bleach activators by testing against tea and bilberry-stained cotton reference fabrics at 40°C in the presence of hydrogen peroxide at pH values ranging from 4 to 10; bleaching efficiency was assessed visually and colorimetrically. Results showed that all of the synthesised compounds were more effective bleach activators across the pH range tested than the standard TAED system.