Organic synthetic pigments: amaranth, carmine, lemon yellow, new red, erythrosine, seduction red, sunset yellow, brilliant blue and indigo and their aluminum lakes, quinoline yellow.
Inorganic synthetic pigments: titanium dioxide and synthetic iron oxide.
Natural equivalent synthetic pigments: β -carotene and lycopene.
Other synthetic pigments: sodium (potassium) copper chlorophyll: copper (potassium) chlorophyll.
Organic synthetic pigment aluminum lake is a special colorant made by reacting pure organic synthetic fuel with alumina, cleaning and drying, which makes water-soluble pigment precipitate on insoluble substrate. It is insoluble in any medium and colored by diffusion in some carriers such as sugar, oil, glycerol and syrup.
Organic synthetic pigments are structurally divided into azo pigments (amaranth, carmine, sunset yellow, lemon yellow, etc. ) and non-azo pigments (erythrosine, brilliant blue, indigo, etc. The molecular weight of these pigments is between 450 and 880, and the maximum absorption wavelength is between 428 and 630 nm. Its redox resistance is poor; Stable heat and light resistance (except indigo); Carmine, seductive red, sunset yellow and indigo are unstable under alkaline conditions, while erythrosine and indigo are unstable under acidic conditions.