Additives translucent/opaque resins

We will begin our discussion with the base polymer itself. While it is not an additive, it is obviously a main component of our total system and must be discussed in coloristic terms. From a color standpoint, there are three classifications of resins transparent, translucent, and opaque resins. 

Optical properties are related to both the degree of crystallinity and the actual polymer structure. Most polymers do not possess color site units, so are colorless and transparent. But, some phenolic resins and polyacetylenes are colored, translucent, or opaque. Polymers that are transparent to visible light may be colored by the addition of colorants, and some become opaque as a result of the presence of additives such as fillers, stabilizers, moisture, and gases. 

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