UV curable urethane acrylate oligomers for anti-fog coatings
Are UV-curable urethane acrylate oligomers containing ammonium salts suitable for anti-fog coatings? This question has been investigated by researchers from South Korea.
The expected structure of the binder was confirmed by FT-IR and 1H NMR. The UV-curable urethane acrylate oligomer (UV-UAO) was then formulated with reactive monomers and photoinitiators to form coating formulas.
Comparison of UV-curing behaviour
In order to compare the UV-curing behaviour of UV-UAO with conventional oligomers, the photopolymerisation of UV-UAO and SK Cytech “Ebecryl”-series urethane acrylates (EB 8210 and EB 9260) was investigated by photo-differential scanning calorimetry. The anti-fog properties of UV-cured anti-fog (AF) coatings were investigated by contact angle test and anti-fog test. Coating properties such as pencil hardness, pendulum hardness, gloss, and adhesion of the UV-cured films containing UV-UAO were investigated.
Concentration of UV-UAO is important
The results showed that the concentration of UV-UAO in the coating formulation had a great influence on the anti-fog properties of UV-cured AF coating. Especially, UV-cured AF coating containing UV-UAO 65 wt.% showed excellent anti-fog properties without sacrificing other desirable properties such as pencil hardness and adhesion.
The study is published in: Progress in Organic Coatings, Volume 110, September 2017, Pages 122–127
