5.1 Rubber in contact with light colored organic finishes may stain the surfaces in contact with the rubber (contact staining) and surfaces adjacent to or beyond the rubber (migration staining), especially under conditions of heat, pressure, or sunlight. When a light colored rubber veneer or organic coating covers a staining rubber compound, the staining ingredients can diffuse through the veneer or coating and stain the surface (diffusion staining). This staining of light colored surfaces is objectionable to the consumer.
5.2 These test methods provide a means of evaluating staining characteristics of rubber compounds but may not necessarily duplicate the effects of natural exposure conditions.
5.3 Results obtained should not be treated as being equivalent to any natural exposure, unless the degree of quantitative correlation has been empirically established for the material in question.
5.4 These test methods may be used for producer-consumer acceptance, referee purposes, and research and development work.
5.5 The two types of exposures (Fluorescent UV and Xenon Arc) are not equivalent and may produce different test results.