The question every consumer actually asks is simple: does it come off on the cup? Traditional long-wear lipsticks tried to answer it with more wax and more pigment, which buys an hour of wear and a day of tightness. Modern transfer-resistant colour answers it with a polymer film: a thin, flexible layer that physically anchors pigment to the lip surface. The physics is straightforward; the formulation work is in keeping that film comfortable.
The engine: a film former carried by a volatile solvent
| Ingredient | Parts | Role |
|---|---|---|
| Acrylates/Polytrimethylsiloxymethacrylate Copolymer (and) Isododecane (31807-55-3) | 25 | Film former, transfer resistance |
| Isostearyl Isostearate (41669-30-1) | 15 | Branched liquid ester; colour development and comfort |
| Triisodecyl Trimellitate (36631-30-8) | 8 | Gloss and film plasticisation |
| Polyglyceryl-2 Triisostearate (120486-24-0) | 5 | Pigment dispersion and anti-sweating |
| Dicaprylyl Carbonate (1680-31-5) | 32 | Low-viscosity, dry-slip carrier; keeps the film solution workable |
| Pigment (buyer-supplied) | 14.5 | Colour - must be milled fine or the film looks gritty |
| Vitamin E (Tocopherol) (10191-41-0) | 0.3 | Antioxidant |
| Fragrance | 0.2 | Scent |
The film former is supplied pre-dissolved in isododecane, a volatile hydrocarbon. On application the isododecane flashes off within seconds and the acrylate-siloxane copolymer coalesces into a continuous film. The siloxane modification is what makes the film wearable: it keeps the polymer flexible and low-tack, so the colour holds through a smile instead of cracking at the lip lines the way an unmodified acrylate film does.
Why 32% dicaprylyl carbonate
High film-former loads set too fast: the film skins over before you finish applying, and colour drags. Dicaprylyl carbonate is the working dilution - a low-viscosity, dry-feeling carbonate that keeps the polymer solution fluid during application and leaves a soft, powdery slip afterwards. It is deliberately not volatile: what stays behind plasticises the film slightly and keeps pigment suspended, which is why wear time survives a 32% load. Cut this line too far and you will feel it in the applicator stroke long before you see it in the wear test.
The comfort trio
- Isostearyl isostearate (15%) - a fully branched liquid ester with a refractive-index-friendly gloss and a long, cushioned feel; it is the main reason this film does not read as tight.
- Polyglyceryl-2 triisostearate (5%) - a polyglycerol ester that wets pigment and improves anti-sweating; in film systems it also reduces the tendency of pigment to ride on top of the film, where it would transfer.
- Triisodecyl trimellitate (8%) - gloss and mild plasticisation; same role as in classic lipstick, tuned down because the film provides structure.
The honest trade-offs
- Removal needs oil. A film that survives coffee also survives water-based cleansers. Position an oil-based cleanser next to it - our cleansing oil polarity guide covers exactly which esters dissolve these films.
- Comfort is a formula decision, not a filter. Wear time and comfort pull in opposite directions; the branched-ester load is the tuning knob.
- Pigment fineness is non-negotiable. At 14.5% pigment, agglomerates sit in and on the film and become transfer points.
- Storage still matters. The film does not sweat, but the ester phase can migrate in a hot jar - run the same 45 °C cycle you would for a stick.
This formula is one of four reference formulas in our lip care ingredients programme; the sweating mechanism it answers is dissected in Why Your Lipstick Sweats.
Acrylates/Polytrimethylsiloxymethacrylate Copolymer (and) Isododecane, Isostearyl Isostearate, Triisodecyl Trimellitate, Polyglyceryl-2 Triisostearate, Dicaprylyl Carbonate and Vitamin E are available from Shanghai Better Chemical with COA, TDS and samples on request.