HC Red 7

Description

HC Red 7 is a synthetic hair dye classified as a halogenated coumarin (HC) dye, commonly used in permanent hair coloring products to produce vibrant red tones. Unlike traditional oxidation dyes, HC Red 7 does not require ammonia or peroxide to deposit color; however, it is often used alongside them in professional formulations to achieve longer-lasting and more vivid results. The dye molecule works by penetrating the hair shaft and binding to the keratin structure, allowing it to impart a deep, rich red shade that can range from warm crimson to intense burgundy, depending on the concentration and mixing with other dyes. HC Red 7 is prized in the cosmetic industry for its high tinting strength and ability to create bright, luminous reds that are less prone to fading compared to natural colorants. However, like other synthetic dyes, it can cause allergic reactions in sensitive individuals, so proper patch testing is recommended before application. Its stability, vibrancy, and versatility make it a popular choice in both professional and at-home hair coloring kits for achieving bold red hues.

Chemical Structure of HC Red 7

Appearance of HC Red 7

Uses

1. Primary Use in Hair Coloring:

Packing

Export Worthy packing 5 Kg Drum, 25 Kg Drum, 50 Kg Drum.

Storage Conditions

Store in cool and dry place at room temperature, protect from direct sunlight.

Molecular Formula

CAS No.

IUPAC Name

Molecular Weight

Appearance

Solubility

Dye Content (Spectrophotometry)

C₈H₁₁N₃O₃

24905-87-1

2‑[(4‑amino‑3‑nitrophenyl)amino]ethanol

197.198 g/mol

Reddish‑powder

98%

2. Formulation Versatility:

HC Red 7 is compatible with both permanent and demi-permanent hair color products. In permanent dyes, it is usually used with a developer (hydrogen peroxide) to lift the natural hair pigment slightly and enhance color deposition. In demi-permanent or no-lift formulas, it can impart rich red tones without significant lightening, which is ideal for coloring previously dyed or dark hair. Its solubility and stability in oil- and water-based hair dye formulations make it a flexible option for professionals and home-use kits.

Soluble in water, Ethanol, Methanol, Alcohol

3. Combination with Other Dyes for Color Customization:

It is often blended with other HC dyes or oxidative dyes to achieve nuanced shades. For example, mixing HC Red 7 with HC Red 3 can deepen the red tone, while adding HC Yellow 2 can warm the shade. This allows cosmetic chemists to design a spectrum of red hues tailored to consumer preferences, from natural-looking auburn to striking crimson or violet-red tones.

HC Red 7 is a core ingredient for producing vibrant red shades in hair. It is often combined with other HC dyes (like HC Red 3 or HC Yellow 2) to create a range of red tones from bright cherry red to deep burgundy. The dye penetrates the hair shaft, binds to keratin, and deposits its pigment, giving long-lasting color that is vivid and intense. Unlike oxidation dyes, it provides high tinting strength even at low concentrations, which allows formulators to achieve striking reds without using excessive amounts of harsh chemicals.

4. Used in Color-Depositing Conditioners & Masks

Because HC Red 7 is highly pigmented, it is used not only in full dye products but also in color-refreshing shampoos, conditioners, and hair toners. These products deposit small amounts of the dye on pre-colored hair to maintain vibrancy, counteract fading, and enhance shine. The dye’s affinity for hair keratin makes it ideal for gradual color boost without harsh chemical processes.

5. Professional Salon Applications:

In salons, HC Red 7 is a staple for achieving red hair shades on clients, particularly when aiming for bright or neon reds, which are difficult to obtain with traditional oxidation dyes alone. It can also be used in multi-step coloring processes, such as pre-lightening followed by deposition of HC Red 7 to achieve luminous red shades even on dark or resistant hair.

6. Safety and Regulatory Uses:

HC Red 7 is included in many commercially available hair dyes because it is approved in certain concentrations for cosmetic use in various countries. While it is potent and effective, formulators must adhere to regulations regarding maximum allowed percentages to prevent irritation or allergic reactions. Its predictable behavior in formulations makes it suitable for both mass-market and professional-grade products.

7. Cosmetic Innovation:

Beyond simple hair coloring, HC Red 7 is used in creative and fantasy hair color products, such as red highlights, streaks, ombré effects, and semi-permanent fashion colors. Its strong coloration and lightfastness make it ideal for vivid, artistic applications that appeal to younger or trend-conscious consumers.

CI No.

15510