Ingredient review
PEG-6 Sesquibenzotriazolyl Butyl Hydroxyphenylpropionate
INCI: PEG-6 SESQUI(BENZOTRIAZOLYL T-BUTYL HYDROXYPHENYLPROPIONATE)
A highly effective, photostable UV filter that offers broad-spectrum protection without the white cast of older mineral sunscreens.
In plain English
This ingredient is a sunscreen agent that protects your skin from both UVA and UVB rays. Unlike some older sunscreens that leave a chalky white layer, it spreads evenly and feels light on the skin. It also helps keep other sunscreen ingredients from breaking down in sunlight, so your protection lasts longer.
Review score
Safety, usefulness, and evidence
Strong fit for many routines
The evidence base is relatively strong for its common cosmetic role.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- semi synthetic
- Evidence
- strong
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Easy yes for most routines
PEG-6 Sesquibenzotriazolyl Butyl Hydroxyphenylpropionate 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.
- Step 1Start with the score, then check the irritation and clogging risk before judging PEG-6 Sesquibenzotriazolyl Butyl Hydroxyphenylpropionate.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- 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
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
strongThere is a stronger practical or research basis for the ingredient role described here.
What it is
A hybrid UV filter that combines a UV-absorbing organic molecule with a silica shell, creating microparticles that both absorb and scatter UV radiation.
How it works
The organic core absorbs UV light and converts it into harmless heat, while the silica shell scatters remaining UV rays. This dual action provides broad-spectrum protection and improves photostability, meaning the filter doesn't degrade quickly under sunlight.
Pros
Excellent photostability
This filter resists degradation from sunlight, meaning your sunscreen stays effective longer during outdoor activities.
Minimal white cast
Unlike many mineral filters, it blends into most skin tones with only a slight sheen, making it more cosmetically elegant.
Cons and cautions
Potential sheen on dark skin
On very deep skin tones, it may leave a faint whitish or purplish cast, though less than traditional zinc oxide.
Limited global availability
Not approved as a UV filter in all countries (e.g., the US), so you may not find it in locally sold sunscreens everywhere.
Best for
- Anyone seeking reliable daily sun protection
- People with sensitive skin who react to chemical sunscreens
Use caution if
- Those who prefer completely mineral-based sunscreens (e.g., only zinc oxide or titanium dioxide)
Usage tips
Safety summary
Extensively tested and considered safe for use in sunscreens at concentrations up to 10%. It has a low irritation profile and is not known to be a significant allergen. Regulatory approvals vary by country.
Research notes
Multiple peer-reviewed studies confirm its broad-spectrum efficacy and photostability. It is one of the most photostable UV filters available, often used to stabilize avobenzone. Human safety data supports its low irritation and sensitization potential.
Common label clues
- Typical concentration
- Up to 10% in leave-on products
- Regulatory status
- Approved as a UV filter in the EU, Australia, and many other regions; not currently approved by the FDA for use in sunscreens sold in the United States.
- Common uses
- Sunscreens, Moisturizers with SPF, BB creams, Makeup primers
- Environmental note
- Studies suggest this filter has low potential for coral reef toxicity compared to some other chemical UV filters, but environmental impact data is still emerging.
Good to know
- This ingredient is often listed as Tinosorb M on product labels.
- It is considered a hybrid filter because it contains both organic and inorganic components.
Common questions
What is PEG-6 Sesquibenzotriazolyl Butyl Hydroxyphenylpropionate in beauty products?
This ingredient is a sunscreen agent that protects your skin from both UVA and UVB rays. Unlike some older sunscreens that leave a chalky white layer, it spreads evenly and feels light on the skin. It also helps keep other sunscreen ingredients from breaking down in sunlight, so your protection lasts longer.
What does PEG-6 Sesquibenzotriazolyl Butyl Hydroxyphenylpropionate do in a beauty product?
The organic core absorbs UV light and converts it into harmless heat, while the silica shell scatters remaining UV rays. This dual action provides broad-spectrum protection and improves photostability, meaning the filter doesn't degrade quickly under sunlight.
Is PEG-6 Sesquibenzotriazolyl Butyl Hydroxyphenylpropionate safe for most people?
Extensively tested and considered safe for use in sunscreens at concentrations up to 10%. It has a low irritation profile and is not known to be a significant allergen. Regulatory approvals vary by country.
Who should be careful with PEG-6 Sesquibenzotriazolyl Butyl Hydroxyphenylpropionate?
Those who prefer completely mineral-based sunscreens (e.g., only zinc oxide or titanium dioxide)
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.