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.
Tinopal® OB features excellent resistance to heat, exceptional whitening properties, good light fastness and low volatility. It has a brilliant bluish cast, is readily soluble in organic solvents and features good compatibility in various substrates.
Tinopal® OB enhances the whiteness of the substrate. In combination with dyes, the product produces particularly bright shades. Its excellent heat resistance renders Tinopal® OB suitable for all relevant processing conditions.
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.