Abstract: Plastic additives which are useful as nucleating agents and which are especially useful for improving the optical properties of polymeric materials are provided. More particularly, this invention relates to certain symmetric DBS compounds comprising specific pendant groups, such as C3-C6 alkyl, C1-C6 alkoxy, phenyl, and methylenedioxy (as the combination of two available sites on the pertinent ring system), as well as wherein the individual benzylidene ring systems may be indan or tetralin. Because of the required symmetrical configuration, the pendant groups on each ring system of the dibenzylidene sorbitol compound must be located at the same positions. Such compounds may be added to or incorporated within polymer compositions which may then be utilized within, as merely examples, food or cosmetic containers and packaging.

Abstract: The present invention relates to a container preform comprising: a polymer suitable for the production of a stretch blow molded bottle and at least one organic or metallated organic near infrared absorbing compound which absorbs at least twice as much light between about 700 nm and about 1200 nm as between about 400 mn and about 700 nm wherein said near infrared absorbing compound is present in an amount sufficient to improve reheat rate of said preform. Suitable near infrared absorbing compounds include phthalocyanines, 2,3-napthalocyanines, squaraines (squaric acid derivatives), croconic acid derivatives, substituted indanthrones and certain highly substituted anthraquinones. A process for improving the reheat rate of a container preform is also disclosed.