Advantages of photoinitiator in use

Photoinitiator, also known as photosensitizer or photocuring agent, is a type of ultraviolet light (250~420nm) or visible (400~800nm) absorb certain wavelengths of energy that produce free radicals and cations, triggering polymerization of cross-linked compounds.

Ideal photoinitiators should have the following advantages:

(1) cheap, simple synthesis;
(2) photoinitiator and its light products should be nontoxic and odorless;
(3) good stability, easy to store for a long time;
(4) the absorption spectra of photoinitiator must match with the emission spectrum of the radiation source, and it has a higher molar extinction coefficient;
(5) as most photoinitiation jump to excited Singlet after absorbing light energy, jump between initiator channeling need higher efficiency;
(6) a higher efficiency

In the UV curing systems, including UV gel, UV coating, UV ink, etc accept or absorb energy, a chemical change takes place itself, and it is decomposed into free radical or cationic, then polymerization is triggered.

As most of the photoinitiator is small molecular photo-initiators, it is volatile and migration in storage, resulting in low efficiency of photopolymerization, bad smell, and even toxic, these have a bad effects of UV inks used in food packaging.

Currently, low odor and nontoxic photoinitiator has been developed, such as polymer photoinitiator. It has excellent performance and can ease the transfer. Meanwhile, polymeric photoinitiators have the following characteristics: regulation of distances between photosensitive groups can be obtained with different reactive polymeric photoinitiators; use synergies improved photosensitive properties of optically active groups; prevent yellowing and aging of the ink layer. Polymer photoinitiator for UV printing inks can be used for food packaging and has better performance.

Radiation curing technology is an items of energy-saving and environmental technology. UV, EB, infrared light, visible light, laser light, and chemical fluorescent, and other radiation light irradiation curing are completely efficient, enabling, economical, energy saving and environmental friendly. . Photoinitiator is one of the important components of UV-curable adhesives and it plays a decisive role in curing speed. After UV exposure to UV, the absorb light energy divided into two active free radicals, then initiate chain polymerization of active diluent and photosensitive resin and adhesive curing, which is characterized by fast, environmental protection and energy saving. Photoinitiator focuses on the developing trend of hybrid, light type, water base, macromolecules and so on, and the use of dual-cured, which receives impressive effect. Click here!