Ingredient review

Acrylates/Steareth-50 Acrylate Copolymer

INCI: ACRYLATES/STEARETH-50 ACRYLATE COPOLYMER

A gentle synthetic thickener that helps create smooth, stable lotions and creams without clogging pores.

beautyskincarethickener

In plain English

This ingredient is a synthetic polymer—a long chain of repeating molecules—that helps water-based products feel thicker and more luxurious. It works by swelling in water and forming a network that traps liquid, giving creams and lotions a smooth, spreadable texture. It also helps keep oil and water mixed together so the product doesn't separate. Because it stays mostly on the skin's surface and doesn't penetrate deeply, it's considered very low risk for irritation or clogging pores.

Quick decision guide

Useful, but context matters

Acrylates/Steareth-50 Acrylate Copolymer 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 Acrylates/Steareth-50 Acrylate Copolymer.
  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 copolymer made from acrylic acid and a steareth-50 (a polyethylene glycol ether of stearyl alcohol) group. It is designed to thicken water-based formulas and stabilize emulsions (mixtures of oil and water).

How it works

When added to water, the polymer chains unwind and absorb water, swelling to increase the viscosity (thickness) of the product. The steareth-50 portion helps it interact with both water and oil phases, making it an effective stabilizer for creams and lotions. It also helps suspend particles and improve the feel of the product on skin.

Pros

Gentle on skin

This polymer is considered very low risk for irritation or allergic reactions, making it suitable for sensitive skin types.

Non-comedogenic

It does not clog pores, so it's a safe choice for acne-prone skin and won't contribute to breakouts.

Cons and cautions

Synthetic origin

It is a man-made ingredient, which may be a drawback for consumers who prefer natural or organic skincare products.

Potential tackiness

In high concentrations, it can leave a slightly sticky or tacky feel on the skin, though this is rare in well-formulated products.

Best for

  • Anyone looking for a gentle thickener in their skincare
  • People with sensitive or acne-prone skin who want non-comedogenic formulas

Use caution if

  • Those seeking 100% natural or organic formulations

Usage tips

Use in water-based formulas at 0.1–2% for optimal thickening without tackiness.
Neutralize with a base (e.g., triethanolamine) if needed to achieve full viscosity.
Combine with other thickeners for customized texture.

Safety summary

Acrylates/Steareth-50 Acrylate Copolymer is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, and no significant safety concerns have been raised by regulatory bodies or dermatological research.

Research notes

Research on this specific copolymer is limited, but it is structurally similar to other acrylate copolymers that have been extensively reviewed and deemed safe by the Cosmetic Ingredient Review (CIR) panel. Studies indicate low skin irritation and sensitization potential.

Common label clues

Typical concentration
0.1% to 2%
Regulatory status
Approved for use in cosmetics in the US (FDA), EU (CosIng), and other major markets. No known restrictions at typical use levels.
Common uses
Creams, Lotions, Serums, Cleansers, Sunscreens
Environmental note
As a synthetic polymer, it is not biodegradable and may persist in the environment. However, it is used in very small amounts and is not considered a major environmental concern.

Good to know

  • This ingredient is often used in combination with other polymers to fine-tune the feel of a product.
  • It is stable across a wide pH range (typically pH 4–10), making it versatile for many formulations.

Common questions

What is Acrylates/Steareth-50 Acrylate Copolymer in beauty products?

This ingredient is a synthetic polymer—a long chain of repeating molecules—that helps water-based products feel thicker and more luxurious. It works by swelling in water and forming a network that traps liquid, giving creams and lotions a smooth, spreadable texture. It also helps keep oil and water mixed together so the product doesn't separate. Because it stays mostly on the skin's surface and doesn't penetrate deeply, it's considered very low risk for irritation or clogging pores.

What does Acrylates/Steareth-50 Acrylate Copolymer do in a beauty product?

When added to water, the polymer chains unwind and absorb water, swelling to increase the viscosity (thickness) of the product. The steareth-50 portion helps it interact with both water and oil phases, making it an effective stabilizer for creams and lotions. It also helps suspend particles and improve the feel of the product on skin.

Is Acrylates/Steareth-50 Acrylate Copolymer safe for most people?

Acrylates/Steareth-50 Acrylate Copolymer is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, and no significant safety concerns have been raised by regulatory bodies or dermatological research.

Who should be careful with Acrylates/Steareth-50 Acrylate Copolymer?

Those seeking 100% natural or organic formulations

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.