This color contains the following pigments:
organic, fluorone dye
Rhodamine B is a staining violet dye that has fluorescent properties. It is extremely soluble in both water and alcohol. In art materials it is laked as a pigment.
Rhodamine B, like all fluorescent dyes, is not considered to be lightfast. It is recommended for permanent works of art only if they can be adequately protected from exposure to ultraviolet light.
The fluorescent dye Rhodamine B is toxic, and its use is banned in food, textiles, and cosmetics. It is harmful if swallowed, inhaled, or absorbed through the skin. It has been shown to be carcinogenic in rats when injected subcutaneously, producing local
Rhodamine B, discovered in 1887, is used as a staining fluorescent dye in the biological sciences, for microscopy. It is also used as a laser dye. Because of its low cost, high tinting strength, solubility in water and alcohol, and relative stability for a fluorescent, it has sometimes been used as a food colorant, even though its use in food and cosmetics has been banned in most countries for many years. There have been several highly publicized recalls of food and cosmetic products contaminated with Rhodamine B.
Quinacridone Magenta is a semi-transparent and powerful bluish red with an impressive mixing range. It makes an excellent glazing color and is one of the bluest of the Quinacridone colors. The pigment's properties vary considerably, depending on how it is ground. Quinacridone pigments have relatively low tinting strength in general. For this reason, quinacridone colors are often expensive, because more pigment is required in the formulation.
Quinacridone Magenta offers very good lightfastness in most media, but some have argued that it is less lightfast in watercolor form. Although Quinacridone Magenta received only a passing grade of "fair" under ASTM test protocols, other test results have rated the pigment very good to excellent. Transparent reddish violet pigments in general have more problems with lightfastness than any other range of colors. PR122 is often used as the Magenta of CMYK (four color) process printing because it offers a better tradeoff between tinting strength and lightfastness than other pigments in its class.
Quinacridone Magenta has no acute hazards. Overexposure to quinacridone pigments may cause skin irritation. Quinicridone pigments contain a compound found to be a skin, eye, and respiratory irritant.
Quinacridone Magenta came from a red violet aniline dye that was first produced in 1858 by Natanson. It was called Magenta to commemorate a battle in Magenta, Italy. Over time, Magenta became the standard color name for a deep, violet red. Although quinacridone compounds became known in the late 19th century, methods of manufacturing so as to make them practical for use as commercial pigments did not begin until the 1950s. PR122 has become particularly popular in the formulation of Magenta for CMYK process printing.