Synthesis and UV-protective properties of monoazo acid dyes based on 2-hydroxy-4-methoxybenzophenone

Monoazo acid dyes containing benzophenone groups were synthesized by the diazo-coupling process and applied to the dyeing of silk as UV radiation protective dyes. The structures of dyes were confirmed by MS and 1H-NMR. The results showed that the exhaustion reached over 85%, the T(UVA) and T(UVB) were 3.3% and 3.4%, respectively. The silks dyed with these dyes had very good ultraviolet radiation protection capability.