Abstract: It has been discovered that the polymerization of diene compounds, such as isoprene, may be inhibited by the addition of a composition that contains a at least one phenylenediamine, at least one sterically hindered phenol, and at least one hydroxylamine. This three-component composition exhibits synergistically improved results over the use of the components individually or in paired combinations. In one preferred embodiment, the polymerization inhibiting composition includes phenylenediamine (PDA), butylated hydroxytoluene (BHT), and N,N′-diethylhydroxylamine (DEHA).

Abstract: The present invention relates to a toothbrush utilized for properly cleaning all teeth, including hard to reach back teeth. It includes a tapering head having bristles extending outward from its end. This toothbrush improves the quality of brushing by being configured to be readily maneuverable within confined portions of a user's mouth. The brushing surface formed by the bristles is substantially planar with the distance between adjacent bristles being substantially consistent throughout the head. This assures an even cleaning of the teeth, and also provides for even wear of the bristles.