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ACID BLACK 131

Description

Acid Black 131, also known as CI 20470, is a synthetic dye primarily used in hair coloring products. This coal-tar derived colorant belongs to the azo dye family and is characterized by its deep black hue. The compound is water-soluble and exhibits excellent affinity for keratin, the primary protein in hair.

In hair coloring formulations, Acid Black 131 provides intense, long-lasting black shades with good coverage of gray hair. It is often combined with other dyes to create various dark tones and enhance color depth. The dye's molecular structure allows it to penetrate the hair shaft effectively, resulting in uniform color distribution.

While Acid Black 131 offers strong coloring properties, it is important to note that some individuals may experience skin sensitization or allergic reactions. Patch testing is recommended before use. The ingredient's stability in hair care products is generally good, but it may be affected by exposure to strong oxidizing agents or extreme pH levels.

Regulatory bodies, including the European Commission, have approved Acid Black 131 for use in hair dye products, subject to certain concentration limits and labeling requirements. Formulators should adhere to these guidelines when incorporating this ingredient into hair coloring products.