Ingredient review

CI 20470

INCI: CI 20470

CI 20470 is a safe, widely used synthetic black dye for rinse-off products, but offers no skincare benefit.

beautyskincarecolorant

In plain English

CI 20470 is a man-made black colorant added to products like shampoo and soap to make them look dark or black. It does not improve your skin or hair—it's purely cosmetic. In rinse-off products, it is considered safe at the tiny amounts used, but it may stain fabrics or skin temporarily.

Review score

Safety, usefulness, and evidence

3.0Fair
3.0/ 5

Useful in the right context, but not low-maintenance

The evidence base is useful, but some claims depend heavily on the formula.

Risk flags are low for most users, though the finished product can still irritate.

Source
synthetic
Evidence
moderate
Irritation
low
Clogging risk
low
How reviews are scored

Quick decision guide

Read the cautions before using

CI 20470 is generally a lower-concern ingredient when the full formula suits your skin.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging CI 20470.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.

Score terms in plain English

Irritation risk

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

CI 20470 is a synthetic azo dye that produces a deep black color. It is also known as Acid Black 1 or Acid Black 10B and is commonly used in rinse-off personal care products.

How it works

It works by absorbing and reflecting light in the visible spectrum to create a black appearance. In a product, it dissolves in water and evenly distributes to give a uniform dark shade.

Pros

Effective colorant

Provides a consistent, deep black shade in rinse-off products like shampoos and body washes.

Low irritation risk

At typical low concentrations, it rarely causes skin irritation for most people.

Cons and cautions

No skincare benefit

It is purely aesthetic and does not moisturize, protect, or improve skin or hair.

Potential staining

Can leave temporary black marks on skin, towels, or clothing, especially in high concentrations.

Best for

  • Anyone who wants a black-colored rinse-off product
  • People without sensitivities to synthetic dyes

Use caution if

  • Individuals with known allergies to azo dyes
  • Those seeking skincare benefits from colorants

Usage tips

Use in rinse-off products only to minimize skin contact time.
Rinse thoroughly after use to reduce the chance of staining.
Avoid contact with light-colored fabrics until the product is fully rinsed.

Safety summary

CI 20470 is considered safe for use in rinse-off cosmetics at low concentrations. It has a low irritation and comedogenic risk, but individuals with azo dye allergies should avoid it.

Research notes

Safety assessments by the EU Scientific Committee on Consumer Safety (SCCS) and FDA support its use in rinse-off products. No significant toxicity or sensitization has been reported at authorized levels.

Common label clues

Typical concentration
Very low (typically less than 1%)
Regulatory status
Approved for use in rinse-off cosmetics in the EU (Annex IV) and by the US FDA as a color additive, subject to purity and concentration limits.
Common uses
Shampoos, Shower gels, Soaps, Hair dyes
Environmental note
As a synthetic azo dye, it may persist in wastewater and is not biodegradable; proper disposal is important.

Good to know

  • CI 20470 is approved for use in cosmetics in many regions, including the EU and US, with concentration limits.
  • It is not recommended for leave-on products due to higher exposure risk.

Common questions

What is CI 20470 in beauty products?

CI 20470 is a man-made black colorant added to products like shampoo and soap to make them look dark or black. It does not improve your skin or hair—it's purely cosmetic. In rinse-off products, it is considered safe at the tiny amounts used, but it may stain fabrics or skin temporarily.

What does CI 20470 do in a beauty product?

It works by absorbing and reflecting light in the visible spectrum to create a black appearance. In a product, it dissolves in water and evenly distributes to give a uniform dark shade.

Is CI 20470 safe for most people?

CI 20470 is considered safe for use in rinse-off cosmetics at low concentrations. It has a low irritation and comedogenic risk, but individuals with azo dye allergies should avoid it.

Who should be careful with CI 20470?

Individuals with known allergies to azo dyes Those seeking skincare benefits from colorants

Research sources

Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.