- ▸ Liquid Type I alpha-hydroxyketone photoinitiator for fast, low-yellowing surface cure of clear UV coatings (Coatings & Construction)
- ▸ Highly compatible liquid for UV/UV-LED clear inks and overprint varnishes (Industrial Manufacturing)
- ▸ Cures clear UV-curable adhesives and plastics; common blend partner with TPO (Plastics & Polymers)
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
Request SDS →2-Hydroxy-2-methylpropiophenone (2-hydroxy-2-methyl-1-phenyl-1-propanone, CAS 7473-98-5) is a clear liquid photoinitiator. Identity: PubChem.
What it is
A Type I α-hydroxyketone that cleaves under UV into radicals for efficient surface cure with low yellowing. Being a liquid, it is easy to dose and disperse, and it can also act as a reactive diluent in some systems.
How it cures
2-Hydroxy-2-methylpropiophenone is a liquid Type I α-hydroxyketone — the liquid counterpart to 1-hydroxycyclohexyl phenyl ketone. It gives fast, low-yellowing surface cure of clear UV systems and is easy to handle and meter as a liquid.
Applications
It is used for surface cure of clear coatings, overprint varnishes, clear inks, adhesives and wood finishes, typically blended with a deep-curing acylphosphine oxide such as TPO; compare with the solid 1-hydroxycyclohexyl phenyl ketone.
Forms, grades and handling
2-Hydroxy-2-methylpropiophenone is supplied as a clear, low-viscosity liquid. Photoinitiators are light-sensitive — store cool and dark. Many are fine powders or liquids that require dust/handling controls per the current Safety Data Sheet (SDS). Each lot ships with a Certificate of Analysis (CoA) and Technical Data Sheet (TDS).
Bulk supply and RFQ
RawSource sources 2-hydroxy-2-methylpropiophenone direct from producers in bulk, with CoA, TDS and SDS per lot. Tell us your lamp (mercury or LED wavelength), system (clear or pigmented) and cure target, and we will quote the right grade or blend. Compare the full range and selection logic in the photoinitiators guide.
Typical Properties
Typical reference values, not a specification; the Certificate of Analysis (CoA) for the lot governs.
| Property | Typical Value |
|---|---|
| Chemical / type | 2-Hydroxy-2-methylpropiophenone — Photoinitiator (Type I, hydroxyketone) |
| Type | Type I (cleavage), α-hydroxyketone (liquid) |
| Cure | Surface cure; low yellowing |
| Absorption | UV (mercury-lamp range) |
| Appearance | Clear liquid |
| CAS Number | 7473-98-5 |
| Molecular Formula | C10H12O2 |
| Handling | Light-sensitive; refer to the current SDS |
Regulatory & registration requirements
- TSCA (US):
- REACH (EU):
- EC number: 231-272-0
Source: EPA TSCA Inventory (July 2025 release) · ECHA CHEM — retrieved 2026-07-12
Frequently Asked Questions
What is 2-hydroxy-2-methylpropiophenone used for?
2-Hydroxy-2-methylpropiophenone (CAS 7473-98-5) is a liquid Type I hydroxyketone for fast, low-yellowing surface cure of clear UV coatings, varnishes, inks and adhesives, usually with TPO for through cure.
Is 2-hydroxy-2-methylpropiophenone a liquid?
Yes — it is a clear liquid (the liquid analogue of solid 1-hydroxycyclohexyl phenyl ketone), which makes it easy to meter and disperse and lets it double as a reactive diluent in some systems.
What is the difference between 2-hydroxy-2-methylpropiophenone and 1-hydroxycyclohexyl phenyl ketone?
Both are Type I α-hydroxyketones; 2-hydroxy-2-methylpropiophenone is liquid and 1-hydroxycyclohexyl phenyl ketone is solid. Choose the former for liquid handling, the latter for a solid/slightly lower odor.
Does 2-hydroxy-2-methylpropiophenone yellow?
It is a low-yellowing surface-cure initiator suited to clear systems; pair it with an acylphosphine oxide for deep cure.
How is bulk 2-hydroxy-2-methylpropiophenone supplied and quoted?
RawSource supplies it as a liquid in bulk with CoA, TDS and SDS. Pricing is quote-based on grade and volume; submit an RFQ.
What is the REACH and TSCA regulatory status of 2-Hydroxy-2-methylpropiophenone (2-Hydroxy-2-methyl-1-phenylpropan-1-one)?
2-Hydroxy-2-methylpropiophenone (2-Hydroxy-2-methyl-1-phenylpropan-1-one) (CAS 7473-98-5) is subject to U.S. TSCA Inventory requirements; supplying it into the EU requires valid REACH registration ((EC) No 1907/2006). RawSource cannot verify a third-party supplier's registrations — buyers should require documented TSCA and REACH compliance for their jurisdiction and volume (EC 231-272-0).