Measuring Opaque Plastics

Opaque plastics can be easily measured with a reflectance-based spectrophotometer. Lot to lot consistency is easily measured if careful consideration to sample selection and presentation is followed. Below is a listing of the qualities of an ideal sample:

Obviously all of these qualities are not always present in plastic goods. When developing standards and color methods, always try to satisfy as many of the qualities above as possible. Development of a repeatable sample presentation method is critical. For example, if the samples are textured, rotation of the plaque and averaging several measurements may be required to achieve repeatable results.