Lemon also known as tartrazine, acid yellow, tartrazine. Lemon, Pinyin Níngméng huáng, English Tartrazine or Lemon yellow, the original meaning of a color, in optics, computer, printing, food and other industries have different definitions of azo type acidic dyes. Orange powder. Dissolved in water was yellow, which continued to show a sodium hydroxide solution was met and yellow. Mainly used in food, beverages, pharmaceuticals and cosmetics and cosmetic coloring, can also be used for dyeing and manufacture of wool, silk lakes. The amino acid by diazotization and 1- (4-sulfophenyl) coupling in an alkaline solution, and refined. For coatings, inks, plastics and other industries and stationery coloring, lemon yellow dye used mainly used for food, medicine, cosmetics and other products of the dye. Appearance: white or almost white powder solution Appearance: clear, ≤BY4 pH: 6.5-7.5 Specific rotation: + 21o - + 24o Melting point: 107-117 ℃ Content: 98.0-100.5% Appearance: orange-yellow powder. Coloring Performance: lemon yellow in tartaric acid, citric acid stability is the most stable colorant A, may be used with other pigment compound, good match.