Properties: Red prisms from alc, no distinct melting point, darkens at 120°. Has a deep red color in water and is yellow to violet in acid solns. uv max (water): 500 nm (e 6800); (0.02N HCl): 490-500 nm (e 5800); (0.0001N NaOH): 540 nm (e 3450). [a]15654 +51.6° (water). Sol in water, alc, concd H2SO4; slightly sol in ether. Practically insol in petr ether, benzene, chloroform.
Optical Rotation: [a]15654 +51.6° (water)
Absorption maximum: uv max (water): 500 nm (e 6800); (0.02N HCl): 490-500 nm (e 5800); (0.0001N NaOH): 540 nm (e 3450)
Derivative Type: Methyl tetra-O-methylcarminate
Percent Composition: C 57.65%, H 5.38%, O 36.98%
Properties: Yellow needles from benzene + petr ether, mp 185-188°.
Melting point: mp 185-188°
Derivative Type: Aluminum calcium lake
Additional Names: Carmine
Properties: Bright-red, light pieces; easily reduced to powder. Practically insol in cold water or dil acids. Partly sol in hot water; sol in solns of alkali hydroxides or their carbonates giving deep red solns; also sol in borax.
Use: Free acid in color photography; pigment for artists' paints; as bacteriol. stain; rarely now as acid-base indicator or as oxidimetric indicator; as a reagent for aluminum; as a complexing agent for cations. Aluminum calcium lake as dye; in inks; coloring foods, drugs and galenicals; in microscopy for making various stains.
产品链接: 1260-17-9››