Tinosorb M (bisoctrizole)
INCI Methylene Bis-Benzotriazolyl Tetramethylbutylphenol
A hybrid UV filter: micro-fine particles that absorb, scatter and reflect UVB and UVA. Photostable and water-dispersed. Permitted in the EU at up to 10%.
- Typical use range
- Up to 10% (EU Annex VI) per the literature, not our formula
- Also known as
- Tinosorb M, Bisoctrizole, MBBT
Methylene bis-benzotriazolyl tetramethylbutylphenol, sold as Tinosorb M and known generically as bisoctrizole, is an unusual filter. It is an organic molecule, but it is supplied as micro-fine particles dispersed in water rather than dissolved in oil. That gives it a hybrid action: the particles absorb UV like an organic filter and also scatter and reflect it like a mineral one.
Coverage is broad, spanning UVB and UVA with a strong contribution around 360 nm, and it is highly photostable. Because it sits in the water phase it lets a formulator add protection without loading the oil phase, which keeps textures lighter. It also helps stabilise other filters in the formula.
It is listed in Annex VI of the EU Cosmetics Regulation at up to 10%, including in nano form, which has been assessed by the EU Scientific Committee on Consumer Safety. On a label it often appears alongside the dispersion aids it arrives with, such as decyl glucoside and propylene glycol.
Where you will find it.
- Silk Veil SPF 50+ PA++++ Sunscreen Sunscreen In the INCI
Percentages are read from each product's stated active complex. Where none is stated the ingredient appears in the full INCI only.
Is Tinosorb M a mineral sunscreen?
No, though it behaves a little like one. It is an organic filter supplied as fine particles that both absorb and scatter UV. It is not zinc oxide or titanium dioxide.
Does it leave a white cast?
Much less than mineral filters at equivalent protection. At high levels a faint white cast can show on deeper skin tones, which is why balanced formulas pair it with oil-soluble filters rather than relying on it alone.
- CosIng, Methylene Bis-Benzotriazolyl Tetramethylbutylphenol (EU cosmetic ingredient database) ec.europa.eu/growth/tools-databases/cosing/
- Regulation (EC) No 1223/2009 on cosmetic products, Annex VI (UV filters allowed in cosmetic products).
- Scientific Committee on Consumer Safety (SCCS). Opinion on 2,2'-methylene-bis-(6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol) (nano), SCCS/1546/15.