Geretsried, March 1st, 2005

Repeatable Quality Control of Plastic Resin Pellets

BYK-Gardner, manufacturer of innovative measuring instruments for the quality control of paints and plastics is introducing a new rotating sampling device to repeatably measure the yellowness index of plastic resin pellets.


The yellowness of transparent plastic pellets is an important parameter as it influences the color of the final product. The measurement of plastic pellets is a challenge because they come in a variety of shapes and sizes. For this reason, it is essential to take multiple readings of one sample in order to average the measured values.


Up to now an operator has had to refill a glass sample cup several times – very time consuming  with varying measurement results. Now, with BYK-Gardner's new automatic sample rotator it is for the first time possible to repeatably measure pellets with minimum operator's effort. As the container is turning over a defined time period, refilling becomes obsolete. The automatic sample rotator improves measurement precision within a plant and from plant to plant. And it saves time into the bargain, as a significantly larger sample volume can be evaluated. Thus the personnel is free for other important tasks.


The sample rotator is mounted on top of the BYK-Gardner color-view, a 45/0 benchtop spectrophotometer. It uses a rotating system that is powered by the instrument. The pellets are poured into a large sample container simulating an infinite film thickness. The container is covered by a lid to avoid any influence of ambient light.


The Windows® based color control software auto-QC that is supplied with each color-view instrument, allows measurement interval time to be set individually dependent on shape and size of pellets. This guarantees repeatable results no matter which resin needs to be measured.


More information is available from:

BYK-Gardner GmbH, P.O. Box 970, 82534 Geretsried, Germany.
Phone: +49/8171/3493-0; Fax: +49/8171/3493-140;


or on the Internet at