What Is Polyester-23?
Polyester-23 is a man-made polymer created when chemists link phthalic anhydride with three small alcohols—neopentyl glycol, trimethylolpropane and glycidyl decanoate—through a reaction called esterification. The result is a clear flexible resin that behaves much like a thin plastic film when it dries on the skin. Work on these kinds of polymers began in the 1960s, and by the 1980s formulators realized they could use them to give makeup and skin care products longer wear and a smooth feel. Today large chemical suppliers produce Polyester-23 in stainless steel reactors where the starting materials are heated, combined then purified into solid flakes or viscous liquid ready for cosmetic labs. You will most often spot it in foundations, liquid lipsticks, long-wear eyeliners, peel-off face masks, hair styling gels and certain sunscreens where a tight yet breathable film is useful.
Polyester-23’s Cosmetic Benefits/Uses
In beauty formulas Polyester-23 serves one main purpose that brings several advantages for both the product and the user.
Film forming: Once the product is applied the polymer spreads into a thin even layer that dries into a flexible film. This film helps makeup resist smudging and fading, lets peel-off masks come off in one piece, boosts water resistance in sunscreens and keeps hair gels holding styles for hours without flaking.
Who Can Use Polyester-23
Polyester-23 is considered suitable for most skin types. Its lightweight film does not add oil so oily and combination skin tend to tolerate it well, while the flexible finish is unlikely to accentuate flakiness on dry skin. People with very sensitive or eczema-prone skin may want to watch for redness or tightness since any film former can occasionally trap heat or sweat, but outright reactions are rare.
The ingredient is fully synthetic with no animal-derived raw materials or by-products, making it acceptable for vegans and vegetarians.
Current safety data show no known issues for pregnant or breastfeeding women when Polyester-23 is used topically in normal cosmetic concentrations. This is not medical advice; anyone who is expecting or nursing should still discuss all personal care products with a qualified healthcare professional.
Polyester-23 does not increase photosensitivity and can safely be worn during daytime exposure to the sun.
Potential Side Effects/Adverse Reactions
Responses to any cosmetic ingredient can vary from one person to another. The effects listed below are possible yet uncommon when Polyester-23 is used as intended by cosmetic manufacturers, and most users will experience none of them.
- Mild skin irritation such as redness itching or a feeling of tightness
- Rare allergic contact dermatitis presenting as a rash or small bumps
- Temporary clogged pores in individuals already prone to congestion
- Eye stinging if the product accidentally gets into the eyes before it sets
If any of these effects occur stop using the product and consult a healthcare professional for personalized guidance.
Comedogenic Rating
Rating: 1/5
Polyester-23 sits on the surface as a light film and contains no heavy oils or waxes so it rarely blocks pores. Studies and anecdotal reports point to a very low incidence of breakouts linked to this polymer. Only extremely congestion-prone users might notice buildup if they layer several film formers.
In short most acne-prone individuals can use products with Polyester-23 without special concern.
No evidence shows it feeds acne bacteria or increases oil production and it plays well with common blemish treatments.
Summary
Polyester-23 is a man-made film former that lays down a thin flexible layer to keep makeup fresh boost water resistance and let peel-off masks come off cleanly. By locking pigments and styling agents in place it stretches wear time and prevents flaking.
The polymer enjoys moderate popularity: it is not as ubiquitous as silicones yet is a go-to choice in long-wear foundations liquid lipsticks and peel-off masks because it is effective and cost friendly.
Safety data show a low risk of irritation allergy and comedogenicity making Polyester-23 a dependable pick for most users including vegans and those who are pregnant. Still it is wise to patch test any new product to make sure your own skin stays happy.