Ingredient review

Acrylamidomethyl Cellulose Acetate Butyrate

INCI: ACRYLAMIDOMETHYL CELLULOSE ACETATE BUTYRATE

A synthetic film-former that helps products like nail polish and mascara last longer and resist water.

beautyskincarefilm-former

In plain English

This is a man-made ingredient that creates a thin, flexible film on your skin, nails, or hair. Think of it like a clear, invisible coat that helps makeup or nail polish stay put and not smudge or wash away easily. It's commonly found in long-wear products.

Quick decision guide

Useful, but context matters

Acrylamidomethyl Cellulose Acetate Butyrate 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 Acrylamidomethyl Cellulose Acetate Butyrate.
  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

A synthetic polymer derived from cellulose (plant fiber) that has been chemically modified to improve its film-forming and water-resistant properties.

How it works

When applied, the ingredient's molecules link together as the solvent evaporates, forming a continuous, flexible film on the surface. This film acts as a barrier that locks in color and resists water and rubbing.

Pros

Long-lasting wear

Creates a durable film that helps nail polish and mascara resist chipping, smudging, and fading throughout the day.

Water-resistant barrier

Forms a protective layer that repels moisture, making it ideal for products meant to withstand sweat or light rain.

Cons and cautions

Synthetic origin

As a chemically modified polymer, it may not appeal to consumers seeking naturally derived or 'clean' ingredient lists.

Potential stiffness

In high concentrations, the film can feel stiff or brittle on nails or hair, which some users find uncomfortable.

Best for

  • Anyone wanting long-lasting nail polish or eyeliner
  • People who need water-resistant makeup for humid conditions

Use caution if

  • Those who prefer exclusively natural or plant-based ingredients

Usage tips

Use in nail polishes and eyeliners for improved durability.
Pair with plasticizers like castor oil to reduce brittleness in formulas.

Safety summary

Considered safe for use in cosmetics at typical concentrations. Low irritation and comedogenic risk. No significant safety concerns reported in regulatory reviews.

Research notes

Limited peer-reviewed studies specific to this ingredient, but it is structurally similar to other cellulose-based film-formers with a long history of safe use in cosmetics. Safety assessments by industry panels support its use.

Common label clues

Typical concentration
0.5% to 5%
Regulatory status
Approved for use in cosmetics in the US (FDA) and EU (CosIng). No known restrictions at typical concentrations.
Common uses
Nail polishes, Mascaras, Eyeliners, Hair styling products
Environmental note
As a synthetic polymer, it is not biodegradable and may persist in the environment. Some manufacturers are exploring bio-based alternatives.

Good to know

  • This ingredient is not water-soluble, so it requires oil-based removers for complete removal.
  • It is often used alongside other film-formers to balance flexibility and strength.

Common questions

What is Acrylamidomethyl Cellulose Acetate Butyrate in beauty products?

This is a man-made ingredient that creates a thin, flexible film on your skin, nails, or hair. Think of it like a clear, invisible coat that helps makeup or nail polish stay put and not smudge or wash away easily. It's commonly found in long-wear products.

What does Acrylamidomethyl Cellulose Acetate Butyrate do in a beauty product?

When applied, the ingredient's molecules link together as the solvent evaporates, forming a continuous, flexible film on the surface. This film acts as a barrier that locks in color and resists water and rubbing.

Is Acrylamidomethyl Cellulose Acetate Butyrate safe for most people?

Considered safe for use in cosmetics at typical concentrations. Low irritation and comedogenic risk. No significant safety concerns reported in regulatory reviews.

Who should be careful with Acrylamidomethyl Cellulose Acetate Butyrate?

Those who prefer exclusively natural or plant-based ingredients

Research sources

CosIng - European CommissionOpenFDA Cosmetics DatabaseOpenPersonal Care Council - Safety AssessmentOpen

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.