The hiding efficiency is consistent with the opacity values (supplementary data, Fig. S4) obtained for HL, HL–chitosan, and HL–PEI of 23.4 ± 0.4, 28.3 ± 0.6 and 8.5 ± 0.2%, respectively. Coating films containing HL and HL–chitosan particles exhibited a high degree of hiding efficiency due to the good dispersion of the pigments. The highest opacity of any preparation was with HL–chitosan resulting from the scattered and refracted light in the chitosan (n = 1.52) andP(MMA/DVB/AA) layers.