Color & Appearance Measurement In The Plastics Industry

The plastic industry is separated into two sections, thermoplastics and thermoset. The Thermoplastics is the majority of the plastic industry. Each section is further divided into highly specialized industries that are responsible for all the plastic things you might commonly see every day. Plastic families in each group are listed in Table I. Four groups are involved in the process of making the final product: raw material manufacturer, processor, converter and equipment manufacturer. At each phase of product processing, quality control (QC) and in some instances computer color matching (CCM), play an integral part in ensuring success of the final product.

A listing of the plastic industry broken into specific industries is displayed in Table II and a list of the typical color and appearance measurements is displayed in Table III. Raw material manufacturers, processors and to an extent converters, would have the most need for QC and CCM capabilities. In these areas, research and development (R&D), technical services, CCM, and QC laboratories are most prevalent. Personnel involved in these areas must have expertise encompassing the entire industry, especially when the product is absorbed throughout the entire mainstream from raw material to converter. Evaluation of resins and additives becomes important as we determine the performance at each stage. In particular, processors preparing color concentrates applicable to a customers needs, have many variables to consider: colorants, resins, stabilizers, dispersing aids, processing aids, loading, and processing equipment.

Most converters and equipment manufacturers need limited color instrumentation. Converters depend upon suppliers to conduct testing and inform them on the "raw material" they will use. They may use basic QC instrumentation to ensure the quality of raw material is maintained within shipping specification.