Applications: 
For low-yellowing, white pigment UV paint; 
for UV screen printing inks, UV offset printing and UV flexo inks; 
low-odor varnish, paper-based paint, light-resistant printing plate, stereolithography. 
 
The photoinitiator TPO-L is a liquid UV initiator for an acrylic-containing resin and a styrene-containing unsaturated polyester. Since it is liquid, the photoinitiator TPO-L is "easy to add" to all formulations. Because TPO-L absorbs long wavelengths in the UV spectrum, it also fully cures coatings with titanium dioxide and flat coatings with titanium dioxide. The coating thus obtained is characterized by extremely low yellowing. 
 
Due to its low volatility, the photoinitiator TPO-L is suitable for the production of low odor formulations. The photoinitiator TPO-L was added in a ratio of 0.3 to 5%, and the polymerizable portion was present in paints and printing inks. 
 
The photoinitiator TPO-L is often combined with other photoinitiators such as photoinitiator 184, photoinitiator 1173, photoinitiator TZT or benzophenone. This promotes surface curing. Because TPO-L absorbs long-wave UV, it is sensitive to sunlight with products containing it. As a result, it is necessary to exclude light having a wavelength below 500 nm during storage and handling (e.g., windows and lamps are covered with a yellow film). 
Storage: TPO-L must be stored in a cool, dry place away from light. Under these conditions, its shelf life in sealed packaging is 2 years.