Optical Brighteners for Plastics Applications

Optical brighteners are used in plastics articles for various objectives, hence whitening and marking are the predominate effects sought after in the plastics industry. Care needs to be taken to choose the correct concentration as compatibility of optical brighteners varies significantly between different polymer substrates. Overdosing may cause incompatibilities resulting in migration as well as suppression of the whitening effect. The use levels in general range between 0.0005 – 0.0010 % in unpigmented polyolefins and 0.005 – 0.100 % in other plastics, depending on substrate and performance requirements of the final application.

Optical brighteners can be applied alone or in a variety of blends and combinations with processing, heat and light stabilizers. Applications Tinopal® OB is highly effective in polymer substrates such as engineering plastics, e. g. polyesters, polycarbonate, polyamides and acrylics, thermoplastic polyurethane, polyvinylchloride, styrene homo- and copolymers, polyolefins, adhesives, and other organic substrates. The main applications of Tinopal® OB include fibers, molded articles, films and sheets. Additional applications include clear lacquers, pigmented lacquers, paints, printing inks and synthetic leather. Tinopal OB can be used as a tracer in a variety of applications.