ASTM D925-06

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.

These test methods provide a means of evaluating staining characteristics of rubber compounds but may not necessarily duplicate the effects of natural exposure conditions.

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.

These test methods may be used for producer-consumer acceptance, referee purposes, and research and development work.

The two types of exposures (Fluorescent UV and Xenon Arc) are not equivalent and may produce different test results.

1.1 These test methods describe techniques to evaluate three types of staining or discoloration that rubber may cause when in contact with or in proximity to another surface that may be light colored.

1.2 The test methods also describe how to qualitatively evaluate the degree of staining or discoloration produced in such situations.

1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.