English Name: Ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate

Chinese Name: Ethyl 2,4,6-trimethylbenzoylphenylphosphinate

MF: C₁₈H₂₁O₃P

MW: 316.33

CAS: 84434-11-7

Appearance: Yellow transparent liquid

Content(%): ≥95.0

Photoinitiator TPO-L Absorption Wavelength(nm): 305, 385

Photoinitiator TPO-L (TEPO) is a highly efficient free radical (Type I) liquid photoinitiator, primarily used for UV curing of acrylic-based resins and styrene-containing unsaturated polyesters.

TPO-L is used in UV coatings with very low yellowing and white pigments;

TPO-L is used in UV screen printing inks, UV offset printing, and UV flexographic inks;

Low-odor varnishes, paper-based coatings, light-resistant printing plates, stereolithography.

TPO-L is a liquid UV initiator used for acrylic-based resins and styrene-containing unsaturated polyesters. Because it is liquid, TPO-L is "easy to add" to all formulations. Since TPO-L absorbs long wavelengths in the UV spectrum, it can also fully cure coatings containing titanium dioxide and flat coatings with titanium white. The resulting coatings are characterized by extremely low yellowing.

Due to its low volatility, TPO-L is suitable for the production of low-odor formulations. TPO-L is added at a ratio of 0.3-5% and appears as a polymerizable component in coatings and printing inks.

TPO-L is often combined with other photoinitiators, such as 184, 1173, TZT, or benzophenone. This promotes surface curing. Because TPO-L absorbs long-wave UV, it and products containing it are sensitive to daylight. As a result, it must be stored and handled away from light with wavelengths below 500 nm (e.g., by covering windows and lights with yellow film).