CI 46500 (CI 73900) is a chemical compound, a synthetic dye with quinacridone (heterocyclic organic compound, a red/purple pigment with excellent resistance to heat, light and chemicals) and is known as Pigment violet 19.

Chemical Name

5,12-dihydroquinolino[2,3-b]acridine-7,14-dione

Chemical Industrial Synthesis Process

• Preparation of reagents. The main raw materials include 2,5-dianilino-terephthalic acid and concentrated sulfuric acid.
• Synthesis of quinacridone intermediate. The production of CI 73900 begins with the cyclization of 2,5-dianilino-terephthalic acid in the presence of concentrated sulfuric acid, forming a dihydro-quinacridone intermediate.
• Oxidation. The dihydro-quinacridone intermediate is oxidized using an oxidizing agent such as hydrogen peroxide to form the quinacridone chromophore, which is responsible for the coloring properties of CI 73900.
• Washing and filtration. The oxidized product is thoroughly washed to remove acidic residues and other impurities, followed by filtration to obtain the desired material.
• Crystallization. The washed product is crystallized to achieve a well-defined crystalline structure, enhancing the optical and color properties of CI 73900.
• Stabilization. The crystallized CI 73900 is stabilized to ensure its stability during transportation and storage, preventing degradation and oxidation.
• Quality control. The CI 73900 undergoes rigorous quality testing to ensure it meets standards for purity, color intensity, and safety. These tests include chemical analysis, spectroscopy, and microbiological testing.

What it is used for and where

Cosmetics

Restricted cosmetic ingredient as IV/102 a Relevant Item in the Annexes of the European Cosmetics Regulation 1223/2009. Substance or ingredient reported:

•     5,12-Dihydroquino[2,3-b]acridine-7,14-dione

Cosmetics - INCI Functions

Colorant. This ingredient has the function of colouring the solution in which it is inserted in a temporary, semi-permanent or permanent manner, either alone or in the presence of the complementary components added for colouring.

Safety

It is an ingredient that has some important health-related contraindications: it should only be used in cosmetic products that have contact with the skin for a short time.

Use in hair colouring products is prohibited.

Molecular Formula    C₂₀H₁₂N₂O₂

Molecular Weight  312.3 g/mol

CAS   1047-16-1

EC number 213-879-2

UNII 11P487375P

DTXSID5027354

Synonyms: 

Pigment violet 19

CI 46500

CI 73900

Quinacridone

Monastral Red

Sunfast Violet