What Is Methacryloyloxyethyl Caproate Phosphate?
Methacryloyloxyethyl Caproate Phosphate is a lab-made ingredient created by reacting hydroxyethyl methacrylate (HEMA) with epsilon-caprolactone, then treating the resulting ester with phosphoric acid. The process yields a group of phosphate esters that dissolve in both water and oil, giving formulators flexibility. Originally explored for dental coatings that need to grip to teeth, its strong adhesive property soon caught the eye of cosmetic chemists looking for long-lasting wear. Today it is produced in modern facilities through controlled polymerization followed by phosphorylation and thorough purification to remove residual monomers.
You will most often see Methacryloyloxyethyl Caproate Phosphate in products that benefit from extra staying power or an even film, such as long-wear foundations, primers, nail polishes, waterproof mascaras, sheet masks, leave-on conditioners, sunscreens and anti-aging serums. It can also appear in specialty treatments that promise transfer resistance or enhanced pigment payoff.
Methacryloyloxyethyl Caproate Phosphate’s Cosmetic Benefits/Uses
In cosmetics this ingredient serves one main role: binding. By creating a flexible yet durable film on the skin, hair or nail surface, it helps pigments, active ingredients and emollients stay where they are placed. This improves color intensity, boosts water and rub resistance, reduces fallout from powders and can give formulations a smoother feel. Its binding ability also stabilizes emulsions, keeping oil and water layers from separating during shelf life and daily use.
Who Can Use Methacryloyloxyethyl Caproate Phosphate
This ingredient is considered gentle enough for most skin types including oily, dry, combination and normal skin. People with very sensitive or broken skin should be cautious because any film-forming polymer can occasionally trap heat or sweat, which may aggravate existing irritation.
The compound is made entirely from synthetic sources so it is suitable for vegans and vegetarians. No animal-derived raw materials or by-products are involved in its manufacture.
Current safety data does not flag specific risks for pregnant or breastfeeding women when the ingredient is used in rinse-off or leave-on cosmetics. Still, this is not medical advice and anyone who is expecting or nursing should show the full product ingredient list to their healthcare provider before using it.
Methacryloyloxyethyl Caproate Phosphate is not known to increase photosensitivity, so it will not make skin more prone to sunburn. Of course daily sunscreen is still important for overall protection.
Because the ingredient forms a durable film it can make makeup harder to remove. Gentle double cleansing or a dedicated makeup remover may be needed to avoid rubbing the skin.
Potential Side Effects/Adverse Reactions
Side effects from topical use can vary from person to person. The points below outline potential reactions but they are uncommon. When used at the low levels found in finished products most people will not experience any problems.
- Mild skin redness or itching
- Stinging sensation on very sensitive or freshly exfoliated skin
- Contact dermatitis in individuals allergic to acrylate type ingredients
- Eye irritation if the product accidentally gets into the eyes
- Nail dryness or brittleness when used in high-adhesion nail formulas
If any irritation or discomfort occurs stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 1 / 5
Methacryloyloxyethyl Caproate Phosphate is a large, water-compatible polymer that sits on the surface to create a thin film rather than seeping into pores. It contains no heavy oils or waxes that typically clog follicles, and published data show a very low tendency to cause comedones in animal or human models. For these reasons formulators classify it near the bottom of the comedogenic scale.
People prone to acne or breakouts can usually use products containing this ingredient without worsening congestion.
Because the film it forms can lock other occlusive ingredients in place, overall pore-clogging risk depends on the full formula, not this single component.
Summary
Methacryloyloxyethyl Caproate Phosphate is a synthetic binder that boosts long-wear, water resistance and texture stability in makeup, skin care, hair care and nail products. It works by forming a flexible phosphate-rich film that grabs onto pigments, actives and the skin or hair surface, while also helping oil and water stay mixed.
It is not a mainstream household name but it is gaining traction in high-performance categories like transfer-proof foundations and waterproof mascaras where staying power is a selling point.
Current research and cosmetic use levels show a strong safety profile with low irritation and minimal comedogenicity, though anyone with known acrylate allergies should stay cautious. As with any new product a quick patch test on a small area is a smart step before full application.