Detection of fluorescent whitening agent or optical brightener
Fluorescent whitening agent test items
Appearance, volatile content, maximum melting point and content are typical test items of fluorescent whitening agent.
How to test fluorescent whitening agent in plastics?
Migration, frost spraying
Usually, the migration and frosting of fluorescent whitening agent are observed in UV lamp, and yellow or green spots can be dispersed on the plastic surface. The fluorescence of spots is much higher than that of other regions.
The whitening effect of fluorescent whitening agent can be estimated by visual method or measured by colorimeter.
Fastness to light
There is no international standard for testing the light fastness of optical brighteners in plastics. Most tests use DIN 54004 as a reference. A better and more objective method is to test the whiteness of plastics with exposure time.